Band 10, Heft 1

Aluminium Covetic metallurgical synthesis along with the characterization of cast material results were presented in this paper. Aluminium- 3% graphite (carbon) composites were fabricated by applying different voltages and amperages of direct current through the stir-casting process. This process, called Covetic based on patent applications of Third Millennium Metals. Obtained casts were tested for their chemical composition, density, tensile strength, hardness, microstructures, and electrical conductivity measurements using an Oxford PMI-Master Pro spark emission spectrometer, a DA-300M density measurement device, a WDW-200 universal tensile test machine, a HBA-3000S automatic Brinell Hardness Tester, a scanning electron microscope with Energy-Dispersive Spectroscopy and an AT512 Precision Ohmmeter, respectively. Moreover, increasing of amperages and/or decreasing of voltages of direct current ensured considerable increasing of electrical conductivity (≈ 34%), the notable decrement in the density (≈ 0.94%), an enhancement in the tensile strength (≈ 18%) and the hardness (≈ 15%) of aluminium Covetic casts compared to the parent metal. In summary, results show that the increasing of amperages and/or decreasing of voltages of direct current has a superior influence on improving electrical conductivity of aluminium-graphite Covetic casts with better mechanical properties.

Study of the synergistic inhibition properties of the combined admixture of 4-methyl-norvalin and 2-methoxy-4-formylphenol (non-toxic organic compounds) on the corrosion of P4 low carbon mold steel in 1.5 M H 2 SO 4 and HCl solution was performed with weight loss measurement, potentiodynamic polarization and optical microscopy analysis. Results obtained showed the inhibition efficiency of the admixed compound performed above the value for effective corrosion inhibition at very low concentrations in H 2 SO 4 solution. However, from mid concentration to the highest concentration studied, the inhibition efficiency of the compound was above 85% from electrochemical tests. In HCl solution the inhibition efficiency of the compound was well above 80% and 90% for weight loss and polarization tests at all concentration studied. Anodic corrosion inhibition mechanism was determined for the compound in H 2 SO 4 according to Freundlich and Frumkin adsorption isotherms due to weak Van der Waals attraction between the inhibitor molecules and the steel’s surface. The mechanism of corrosion inhibition in HCl was calculated to be cathodic type according to Langmuir isotherm model.Morphological images of inhibited and non-inhibited steel surfaces significantly contrast each other though the extent of deterioration was much severe for the steel from H 2 SO 4 solution.

Transport companies operate in a dynamically developing and competitive market. Maintaining the already held position and further expansion requires adjusting the level of services provided to the needs and requirements of customers, as well as continuous surveying, monitoring and adjusting the implemented strategy. There are different methods for such an analysis. This article proposes logistic regression. The research was conducted on the basis of a distribution and trade company dealing with the supply of automotive spare parts. As the most profitable group of customers are local car repair shops, it was this group that was subject to analysis. The quality of service assessment was considered from the point of view of delivery time. The dichotomous form of the predictor taking two values - late and on-time delivery - was determined. From among the possible ones, regressors whose influence was statistically significant and whose modification was possible were selected. The research showed which of them (and how strongly) affect the dependent variable, which allowed for modification of strategy and implementation of new solutions increasing the number of satisfied customers.

Shell Eco-marathon is an international competition to develop a vehicle with the lowest fuel consumption. The Faculty of Mechanical Engineering of the Technical University in Košice has been involved in this competition for 25 years, during which it developed 8 vehicles. For vehicles are important not only low fuel consumption but also high safety. In addition to the low aerodynamic drag of the vehicle, the low weight of the vehicle is important to achieve low fuel consumption. This is achieved by using ultra-light and solid materials in all parts of the vehicle. The latest generation vehicle uses a self-supporting body, which has increased requirements for front and rear stiffness, as discussed in this article.

Industrial waste is constantly increasing, so measures must be taken to recycle it in more practical and environmentally friendly ways. The aim of this study was to investigate the suitability of sawdust wasted particles for the production of cement bonded particleboards, and to enhance their compatibility with cement by using physical pretreatment processes, addition of nano slag and accelerated carbonation curing. All tests were carried out with different manufacturing parameters: sawdust/cement: (20%, 30% and 40%), treated and untreated wood, CO 2 curing and the addition of nano slag. Experiments were performed to assess the mechanical properties of produced particleboards such as density (D), water absorption (WA), thickness swelling (TS), bending strength (BS), and microstructural properties of the cement particleboards. For treated sawdust, the outcomes demonstrated an enhancement in the mechanical and microstructural characteristics of produced cement bonded particleboards by using the accelerated CO 2 curing method for sawdust particleboards. According to Scanning Electron Microscopy (SEM) micrographs, part of the carbonate crystals was found to be diffused into the cell walls and cavities and were found to protrude from sawdust surfaces.

This study is aimed to analyze success of the Enterprise Resource Planning (ERP) System Merging in Chemical Company Singapore that acquired two companies. The success component of ERP system success is using DeLone and McLean success model with qualitative method. The research methodology used detail interview with project implementation team, ERP consultants (8 informants) to get more detail from ERP system merging with information and collected supporting data from the ERP system itself. The result shows that ERP System Merging succeed to increase the system quality of Chemical Company which acquired two companies into one ERP system. It was depicted by the increment of easiness on using the system. The information much more integrated and accurate after the ERP system merging. Meanwhile service quality was increased because of all incidents now monitored in one efficient log system and handled by experienced IT application support team.

Resistive forces associated to boundary layers (‘friction’) are usually out of scale in physical models of hydraulic structures, especially in the case of hydraulically smooth walls, generating distortions in the model results known as scale effects , that can be problematic in some relevant engineering problems. These scale effects can be quantified and corrected using suitable numerical models. In this paper the accuracy of using numerical simulation through the Reynolds Averaged Navier-Stokes (RANS) approximation in order to represent the head losses introduced by friction in hydraulically smooth walls is evaluated for a wide range of Reynolds scales. This is performed by comparing the numerical results for fully developed flow on circular pipes and between parallel plates against experimental results, using the most popular wall treatments. The associated numerical errors, mesh requirements and ranges of application are established for each treatment. It is shown that, when properly applied, RANS models are able to simulate the head losses produced by smooth wall friction accurately enough as to quantify the scale effects present in physical models. A methodology for upscaling physical model results to prototype scale, free of scale effects, is proposed.

To eliminate problems caused by gypsum soil in Iraq (due to gypsum salt under building foundations and projects), this study evaluates the effect of using the proposed stabiliser additives (vehicle waste oil and asphalt powder) to produce a composite enhancement material as a novel solution by examining the shear strength of the gypseous soil using the direct shear and constant head permeability tests. Three burned-oil weights were used (3%, 5%, and 7% by dry soil weight), which were mixed with a constant quantity of asphalt powder (10% of the sample weight) to investigate the shear strength of the composite material. Several factors were considered in this study, including soaking time and moisture content. The main findings reveal that composite material could improve the strength of the gypseous soil. The stabiliser reduces water leakage and percolation by forming an impermeable layer with a very fine texture, causing a significant reduction in the permeability coefficient, which improves the gypseous soil and reduces the collapse phenomenon.

The article discusses the stress optimisation process of the highly loaded disc of a high-speed radial-axial microturbine. At the design stage, the strength optimisation is vitally important for these types of devices because they must withstand very high temperatures (600 ∘ C in this case) and be capable of operating at high rotational speeds (96,000 rpm in this case). Calculations were made using a three dimensional FE numerical model. The optimisation process is strictly connected with the choice of materials — which in this case are Inconel 738 (nickel-cobalt super alloy) and silicon nitride. Several stress reduction methods were developed, which took into account the mass of the disc, the rotational speed of the rotor and the complex shape of the rear part of the disc. Numerical computations helped to choose the best optimisation method, which decreased maximum reduced von Mises stresses by about 45% (from 1,288 MPa to 705 MPa). The methods proposed in this article are universal and can be implemented in the design process of various high-speed radial-axial microturbines. This article could be of interest to scientists and engineers who deal with highly loaded microturbines, which are increasingly used in many industrial sectors.

Abstarct A review of modern methods of forming a mathematical model of power systems and the development of an intelligent information system for monitoring electricity consumption. The main disadvantages and advantages of the existing modeling approaches , as well as their applicability to the energy systems of Ukraine and Kazakhstan,are identified. The main factors that affect the dynamics of energy consumption are identified. A list of the main tasks that need to be implemented in order to develop algorithms for predicting electricity demand for various objects, industries and levels has been developed.

Mechanical alloying can be carried out by a method known as friction stir processing, whereby solid Zn particles in a solution are distributed onto an aluminium alloy plate. The aim of this study was to determine the effects of a volume of Zn particles on the mechanical and physical properties of aluminium 1xxx alloy that had been subjected to friction stir processing. The specimens were plates composed of 1xxx series aluminium. A groove, measuring 12 mm in diameter, was pierced to various depths, and the Zn particles in these containers were then subjected to friction stir processing using a pin-less tool with a diameter of 15 mm. The results showed that the highest hardness was found in the uppermost layer of the workpiece, and this gradually decreased with thickness. An increase in the amount of Zn particles caused an increase in material hardness. The highest hardness of 87.1 HV in the friction stir-processed AA1100 was obtained at the highest volume of Zn compared to the hardness of 44.5 HV, which was obtained for the specimen without the addition of Zn.

The variational method is known as a powerful and preferred technique to find both analytical and numerical solutions for numerous forms of anharmonic oscillator potentials. In the present study, we considered certain conditions for the choice of the trial wave function. The current form of the trial wave function is based on the possible polynomial solutions of the Schrödinger equation. The advantage of our modified variational method is its ability to reduce the calculation steps and hence computation time. Also, we compared the results provided by our modified method with the results obtained by different methods in general but particularly Numerov method for the same problem.

The preferred data for analyzing water availability are those of historical flow series of the sources of interest; however, most Brazilian watersheds do not have sufficient fluviometric monitoring. Such cases require techniques for transposing data from one region to another, otherwise known as ‘flow regionalization’. The present work aimed to compare the method proposed by Secretaria de Meio Ambiente e Desenvolvimento Sustentável (SEMAD) of the state of Goiás with the traditional method of regionalization for determining reference flow at the mouth of the surface catchment basin of the Meia Ponte river. Data from eight fluviometric stations were used for regionalization, with the regression equations being adjusted using four different models. The result revealed that the potential and linear models performed the best, both with R 2 and R 2 a values of 0.996 and 0.995, respectively. The relative error in the application of the potential model and of the method adopted by SEMAD were below 30%. The reference flows obtained by the two best performing methods differed, with flow determined by the traditional method being 5.93% lower than that of the SEMAD equation. Therefore, a more detailed study is recommended to determine which equation models better fit the region.

Much research in the construction industry is based on the concept of a unique project; hence, such concepts (or philosophy) present the construction project as a unit of analysis for the entire completion process that is usually delivered independently. Most decision support tools in construction have been designed at the project level rather than for construction institutions that often implement many projects simultaneously. Typically, these projects have common objectives that create dependencies among them. Then, the success of one project depends on other projects and the existing interrelationships among them. Thus, construction institutions still need to deal with their projects from a portfolio perspective,which requires strategic management at a portfolio level. This paper employs resource management techniques to allocate resources to manage construction portfolios. A case study targeted strategic decision making about financing projects that have stalled. The final recommendation of this paper is to use development and planning software to serve and support strategic decisions in institutions with concurrent stalled projects.

The orthogonalization of Boolean functions in disjunctive form, that means a Boolean function formed by sum of products, is a classical problem in the Boolean algebra. In this work, the novel methodology ORTH [ⴱ] of orthogonalization which is an universally valid formula based on the combination technique »orthogonalizing difference-building ⴱ« is presented. Therefore, the technique ⴱ is used to transform Sum of Products into disjoint Sum of Products. The scope of orthogonalization will be solved by a novel formula in a mathematically easier way. By a further procedure step of sorting product terms, a minimized disjoint Sum of Products can be reached. Compared to other methods or heuristics ORTH [ⴱ] provides a faster computation time.

This research aims to develop an integrated information system for pharmaceutical companies in Indonesia, which has separate business units in two different locations. An Integrated System is needed to provide the value of competence in the technology and information systems that companies use in their business processes. The development stage starts from the assessment and understanding of the current situation both in the business environment and the IS/IT environment. The business environment includes the internal business environment and external business environment.Similarly, the IS/IT environment which includes internal and external IS/IT environments. With a deep understanding of current conditions, it can be determined the Information System(IS) strategy, Information Technology(IT) strategy and future IS/IT strategies. This study reveals the following results: The absence of good system integration with the business units involved makes the company in a weak position. But in terms of opportunity is quite high so that the use of technology and information systems that fit business needs is recommended in this study. The results of this study recommends some applications that can solve problems commonly experienced by companies such as system integration and business process automation to achieve more efficient and effective business processes.

The optimal design of a subsoiler implement is a complex work that includes optimal design, material properties, structural reliability, random variables, soil properties, soil tillage equipment, and optimum safety measures. The main objectives of this study were to design and simulate the deep placement fertilizer applicator (DPFA) by using the finite element method (FEM). FEM simulation software was used to select the optimum material properties and improve the safety factor by considering a range of loads on DPFA. Three applied forces in a static simulation (4500, 5000 and 6000 N) were considered as were three application depths of fertilizers (0.15, 0.20, and 0.25 m), to improve the safety measures of the design. The simulation results showed that the best material property for DPFA is the AISI 4135 QT carbon steel materials. This yields a high strength of 780MPa and an ultimate tensile strength of 950 MPa (Young’s Modulus of 207 GPa and with Poisson’s Ratio of 0.33). The static simulation for 6000 N shows that the DPFA model had a maximum stress and strain of 379.9 MPa and 25.6×10 −4 mm/mm respectively, with a contact pressure of 207 MPa, and a maximum displacement of 3.1 mm. The study results can provide theoretical and technical support for the development of agricultural tools, especially for DPFA in selecting optimum material properties and improving safety factors.

In today’s increasingly globalizing world, the demand for the transport of more and more specific kinds of goods is constantly growing. Greater diversity of the objects of transport extends the range of consignees and consignors, which implies the reduction of the number and volume of consignments. Modern enterprises are no longer interested in mass supplies of large quantities of the same material but strive for flexible supplies of smaller quantities of specific materials out of more suppliers. This manuscript deals with the streamlining of specific transport-logistics processes, including a detailed analysis of the existing pick-up system in relation to transport serviceability of the certain territory starting in the city of České Budějovice (Czech Republic) and a determination of more effective variants for supply. The primary objective will be to find and analyze specific options for streamlining the processes being optimized using the selected method of the graph theory, namely the location problem. In the context of optimization, a specific case study is elaborated with the aim to increase the efficiency of the current pickup system, i.e . serviceability of a particular territory.

Spot welding joints of Al-Mg-Si alloy (AA6061-T6) were produced with and without the addition of copper interlayer using pinless friction stir spot welding (P-FSSW). To investigate the effects of welding parameters on the metallurgical and mechanical properties of the weldment, various tool plunge depth and dwell time were used. Optical microscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy (EDS) have been used for microstructural characterisation.Meanwhile, the mechanical characterisation of the welded joints was evaluated by tensile-shear test. The experimental results showed that a larger bonding area and sound joint were achieved with the addition of Cu interlayer due to the improvement in thermal distribution. Also, an alloying reaction took place between the aluminium substrate and Cu interlayer during P-FSSW, forming intermetallic compounds layer in the interface through the diffusion process. The increasing of dwell time and plunge depth to some extent were beneficial to the formation of the joint and diffusion process, and thus increasing the tensile-shear load of the joints. The observed fracture mode of the joint was either completely shear off in the interface or complete nugget pullout.

The paper shows the usefulness of the roof geometry in determining of building outline. It was pointed out how analysis of the roof skeleton shape avoids many design errors. Omitting the criterion for the shape of the roof skeleton in the case of multi-criteria optimization can pose a lot of difficulties when designing a building. The problem is discussed in the case study.

The purpose of this study was to clarify the silicon-germanium dioxide (SiGeO2) and Aluminum Indium Gallium Arsenide (AlInGaAs) based acoustic optic modulators for upgrading transmission performance characteristics. The transient time response of these modulators is analyzed and discussed in detail. The 3-dB modulation signal bandwidth, diffraction signal efficiency, signal rise time, and signal quality factor with minimum data error rates are also considered. The proposed models with silicon-germanium dioxide and Aluminum Indium Gallium Arsenide acoustic optic modulators were compared to the previous model with silicon acoustic optic modulators. The results confirmed the high-performance efficiency of the proposed models when compared to the previous model, in both the lowest transient time response and the highest acoustic optic modulators speed response.

This study reports the efficient use of a direct laser modulated response measured with the return-to-zero coding scheme in optical transmission systems. The measured direct laser modulated response has a bit rate of 1.2 Gbps for an optical fiber cable of a transmission length of 10 km. The eye diagram analyzer is used to calculate the maximum quality factor and minimum bit error rate of the proposed model. The maximum quality factor is 531.2, and the minimum bit error rate tends to zero for the same optical fiber channel length compared with that of the previous model. The proposed model provides better results than the previous model. The figures of the proposed model are more stable than those of its previous counterpart. Bit error rate approximately tends to zero in the proposed model.

Autonomous vehicles are gaining more and more followers and are becoming a reality. Although the total change of the transport system to an autonomous one still remains a big challenge, the development of navigation, control and supervision systems for vehicles gives hope for an autonomous future. The article describes the rules for choosing a route and the process of outsourcing transport tasks. The formulas for calculating the values of indicators characterizing the transport process are provided in the simple case when vehicles move along a fixed route where there are no disturbances. Additionally, the theory of Markov random systems was used to determine the system capacity, average queue length for servicing and the average number of requests.

The article presents the results of research on the total reaction time of drivers in real traffic conditions. The tested driver had to react to a complex signal by performing a braking manoeuvre. The measurements were based on the author’s method combining the measurements of reaction time during the actual driving with their computer analysis. The research group consisted of 15 drivers with different seniority of driving licences. The study measured the time of perception and the time of leg transfer from the accelerator pedal to the brake pedal. The results were subjected to analysis and on its basis conclusions were formulated.

Traffic modelling and simulation is one of the frequent tools used in road infrastructure design. Software tools designed for traffic simulations are an important supportive tool in decision-making and in choosing the optimal solution. The aim of this paper is to introduce the application of the VISSIM program, in the design and testing a model of the traffic-light-controlled intersection. The traffic on the selected congested intersection is modelled and simulated first for the current state, then for two models with modifications that are to increase the throughput of the intersection. The monitored criterion of the intersection throughput is the length of queues. Both adjustments have led to a significant reduction of the number of vehicles waiting in direction of the greatest congestions. In the first model, the average line length was reduced by 75%, and in the second model, the modifications lead to a fluent passage of right-turn vehicles and a significant reduction in vehicle lines for other directions.

Current business trends push transport companies to improve the efficiency of their entrepreneurial activities, what is closely related to costs reduction and revenues increase. Many transport companies achieve it empirically, but some mathematical algorithms, mainly from operational research, can be used to improve the efficiency of railway transport by finding the optimal solution of specific problems. The paper is focused on using of selected methods from applied mathematics in railway transport. These methods are used mainly for improving the operational efficiency of the transport company, what tends to decrease overall operating costs. Major impact is done by efficient use of railway vehicles and train staff. It can be achieved by optimization as a flow network problem or assignment problem, what is further described in the paper. Mathematical approaches can also positively influence the whole logistic process.

The article deals with the experimental monitoring of the driver’s attention during train operation. SMI eye-tracking technology and eye-tracking glasses we used to measure the train driver’s attention. This unique experiment we performed on the Slovak railway (ŽSR) line no. 120 Bratislava - Žilina, in the section Žilina - Púchov. The measurement took place in the spring of 2017, and the passenger train was operated by the ZSSK electric unit series 671. The article analyses in detail the monitoring of the driver’s attention during train operation. We analysed two typical processes during train driver work: driving at the section (without stopping) and driving through the train station (with stopping). Realised analysis can lead to the identification of critical points on the line, to a better understanding of the driver’s way of work and to contribute to increasing railway safety. The unique measurement procedure and the used technology did not affect the safety of the train operation.

Currently we are saying that we are at the dawn of the fourth revolution, which is marked by using cyberphysical systems and the Internet of Things. This is marked as Industry 4.0 (I4.0). With Industry 4.0 is also closely linked concept Logistics 4.0. The highly dynamic and uncertain logistic markets and huge logistic networks require new methods, products and services. The concept of the Internet of Things and Services (IoT&S), Big Data/ Data Mining (DM), cloud computing, 3D printing, Blockchain and cyber physical system (CPS) etc. seem to be the probable technical solution for that. However, associated risks hamper its implementation and lack a comprehensive overview. In response, the paper proposes a framework of risks in the context of Logistics 4.0. They are here economic risks, that are associated e.g . with high or false investments. From a social perspective, risks the job losses, are considered too. Additionally, risks can be associated with technical risks, e.g . technical integration, information technology (IT)-related risks such as data security, and legal and political risks, such as for instance unsolved legal clarity in terms of data possession. It is therefore necessary to know the potential risks in the implementation process.

The issue of sustainable city logistics has steadily been developed over the last decades. Urban public transport companies can make a significant contribution to the concept of sustainable city logistics. The customers’ perception and satisfaction regarding urban public transport companies can be associated with the increased use of their services. The preference for urban public transport reduces the use of individual car transport, which is linked to the environmental pillar of sustainability. For the customers, the level of the provided service is very important. The article is focused on the evaluation of the outcomes from the primary research concerning the service quality performed by the urban public transport companies in the Hradec-Pardubice residential agglomeration. The goal lies in identifying gaps in service quality. The method used in this article is representative primary research. The primary research was carried out in the form of structured personal interviews with a representative sample of respondents. Selected statistical methods were used to evaluate the data. The results are discussed in the context of published research studies. Research in this article found that respondents are more satisfied with the quality of services performed by the urban public transport companies, but the perception of individual service quality factors varies from one user group to another. The research also confirms a different perceptions regarding customer care and comfort by different age groups of respondents. The article implies that public transport companies should pay attention to setting fare prices for different groups of passengers.

The article contains an analysis of charging electric cars as a way to increase the use of energy produced from a photovoltaic system. A photovoltaic system is described, consisting of two micro installations, with a power output of up to 40 kWp each, supplying two sectors of the building of the Lublin Science and Technology Park. An internet platform for monitoring the operation of a photovoltaic system is presented. Next, an innovative system for monitoring, consumption and production analysis of electric energy in individual building sectors is described. A surplus of energy produced in one of the sectors was found. It was proposed that this excess energy would be used to charge electric vehicles. An analysis of the surplus power generated by the photovoltaic system in excess of the energy consumed by the building sector was used to determine the power available to the wall charger. The surplus of energy produced was used for calculations related to the amount of charging the electric vehicle required and the cost of traveling 100 km. Charging an electric car not only provides a faster return on investment in the installation, but also presents drivers with a very ecological and economical transport solution.

The paper deals with possibilities of assessment of braking efficiency during evaluation of braking system at technical inspection of trucks in conditions of the Slovak Republic. The braking efficiency of the vehicle is evaluated by measuring the braking forces at the roller brake tester. The magnitude of these forces also depends on the loads of the measured vehicle. The paper analyses the results of the practical tests of the braking efficiency measurement of a truck of category N3 and of a vehicle combination consisting of vehicles of category N3 and O4. The analysed vehicle combination was gradually loaded in four different ways and a special situation was the measurement of the braking efficiency of the tractor itself. The instantaneous load on each axle was recorded with portable axle weights. The braking efficiency evaluation was carried out in accordance with the valid methodology, which allows the application of the direct evaluation method, the method of linear extrapolation, the method of the reference braking forces and the indicative evaluation. A vehicle with the same braking system may be assessed as roadworthy or not roadworthy. This is due to the application of different methods of evaluating the braking efficiency and different way of loads at the loading area.

Nowadays, virtual reality enters engineering work. It is widely used in various sectors. It brings new possibilities that result is increasing of productivity and reliability of production, quality of products and processes. One of the areas where virtual reality has been used more and more is logistics. Virtual reality and especially augmented reality offer above all in the area of logistics a perspective related with increasing of effectiveness of processes.Wide possibilities for virtual reality use in logistics can be found in the automotive industry. The paper describes an application of the method of video-mapping in storage logistics. The paper also describes its practical use as a tool for increasing the efficiency of logistics processes, which was presented by a reduction of the processing time of the shipment picking by 10%. The paper also points out the possibilities for applying this method in other industrial areas, it is possible to use the experience gained in automotive and described in this paper.

Process of ready mixed concrete (RMC) delivery is an example of multi-objective optimization due to the conflicting objectives of the parties involved. In order to face this problem, discrete event simulation model of the delivery process is created with input parameters based on the surveyed data of real processes. The model is simulated with different vehicle dispatching policies and the results are analysed focusing on performance indicators. The research results compared in terms of Pareto optimality indicate that employing effective dispatching strategies can reduce both site idle time and waiting time of vehicles.

Noise measurement and evaluation of the existing noise situation is carried out in the vicinity of selected roads to demonstrate the need for the design of anti-noise measures or to assess the effectiveness of the measures. The selection and number of measuring points, time and intervals, the road noise measurement procedure and the measuring instruments used shall be used in accordance with the provisions of the STN ISO 1996-1 and STN ISO 1996-2 standards. During the measurement, it is also necessary to determine the microclimatic conditions of measurement, such as temperature and relative humidity, wind direction and speed, barometric pressure, duration and intensity of precipitation at the measuring point. The determinant for the definition of road traffic noise is the equivalent sound level A or the equivalent sound level in the third octave bands over a given time interval. In specific cases, it is possible to determine the equivalent sound pressure level from individual vehicle transit.

With the upcoming new legislative rules in the EU on Event Data Recorder beginning 2022 the question is whether the discussed data base is sufficient for the needs of clarifying accidents involving automated vehicles. Based on the reconstruction of real accidents including vehicles with ADAS combined with specially designed crash tests a broader data base than US EDR regulation (NHTSA 49 CFR Part 563.7) is proposed. The working group AHEAD, to which the authors contribute, has already elaborated a data model that fits the needs of automated driving. The structure of this data model is shown. Moreover, the special benefits of storing internal video or photo feeds form the vehicle camera systems combined with object data is illustrated. When using a sophisticate 3D measurement method of the accident scene the videos or photos can also serve as a control instance for the stored vehicle data. The AHEAD Data Model enhanced with the storage of the video and photo feeds should be considered in the planned roadmap of the Informal Working Group (IWG) on EDR/ DSSAD (Data Storage System for Automated Driving) reporting to UNECE WP29. Also, a data access over the air using technology already applied in China for electric vehicles called Real Time Monitoring would allow a quantum leap in forensic accident reconstruction.

The aim of this paper is to familiarize the reader with the general application of MCDM methods on a specific example of City Logistics in order to find the optimal solution for operation of the territory. In its introductory part, methods used for quantitative evaluation of variant solutions are briefly described, and then the so-called Forces Decision Matrix Method (FDMM) including the determination of criteria weights using pairwise comparison of variants according to individual criteria on the specific example is applied. In the final part of the paper, the advantages and disadvantages of using this method for more complex tasks with multiple variant solutions based on the results of the practical example are evaluated and the so-called Saaty’s method based on the quantitative pair-wise comparison to partially eliminate differences in the mutual evaluation of weights and criteria is mentioned.

The influence of the cargo weight loaded on the vehicle and the total gross mass of the vehicle on the braking characteristics is often researched from the road safety reason. However, there is not enough knowledge about the influence of weight and load distribution on the loading area of small trucks or vans on their braking characteristics. This article presents the results of measurements of braking decelerations of the van of N1 category and the braking characteristics of a vehicle loaded with different cargo mass with different cargo locations on the loading area. The impact of the longitudinal cargo position on the loading area on the load of the individual axles and thus on the braking deceleration of the vehicle was investigated. The influence of the height of the center of gravity on the dynamic axle load during braking was also determined. Method of direct vehicle deceleration measurement was used by a decelerometer. There were calculated cargo weight and cargo position influences on the dynamic axle load during braking according to the vehicle deceleration.

Distribution tasks or transportation problems when using Operations Research methods are mostly addressed by vehicle routing problem methods dealing with an issue of supplying to several nodes, wherein the route begins in a point of origin and, after accomplishing deliveries to individual nodes, vehicle returns to an initial point. Each node can be operated only once, the order of nodes is not determined; however, the major objective is to find the shortest route possible. The aim of this research study is to formulate options to model delivery routes executed by automated guided vehicles in an extensive logistics areal by applying the specific mathematical optimization method. After description of several fundamental aspects and attributes related to automated guided vehicles, distribution tasks and vehicle routing problems which are discussed in introductory chapters, the most important parts containing the specification of Greedy algorithm, as a very useful optimization method for the given purpose, as well as the very models of cargo delivery by automated guided vehicles without / with initial distance optimization are presented.

The work presents a simulation model of a “driver–automation–autonomous vehicles–road” system which is the basis for synthesis of automatic gear shift control system. The mathematical description makes use of physical quantities which characterise driving torque transformation from the combustion engine to the car driven wheels. The basic components of the model are algorithms for the driver’s action logic in controlling motion velocity, logic of gear shift control functioning regarding direction and moment of switching, for determining right-hand side of differential equations and for motion quality indicators. The model is realised in a form of an application software package, comprising sub-programmes for input data, for computerised motion simulation of cars with mechanical and hydro-mechanical – automatically controlled – transmission systems and for models of characteristic car routes.

Overloaded vehicles pose a real threat to road safety and significantly contribute to the degradation of the road surface. High-Speed Weigh in Motion (HS-WIM) stations are the commonly used method of eliminating them from traffic. In Poland, HS-WIM stations operate in pre-selection mode, sending information to services about the potential exceedance of acceptable standards by a specific vehicle. The article presents the results of the data analysis from selected HS-WIM stations operating on the national road network in Poland indicating significant limitations of the effectiveness of the whole system. The main reason for this may be that carriers use the knowledge about the HS-WIM stations location and working time to avoid inspections. The results presented in the paper indicate, among other things, that in some locations the share of vehicles overloaded with traffic increases significantly outside the working hours of the controlling services. For Light Commercial Vehicle, the share of overloaded vehicles in this group is also significant. Also, the paper indicates that the effectiveness of the procedure for determining vehicle overload has been limited due to errors in classification.

Increasing the number of vehicles on the road network and the growing popularity of sustainable development of urban areas have resulted in the need for implementing efficient and cost-effective traffic measurement methods. From the perspective of traffic management, up-to-date information about vehicle density and access to historical data are the key components of traffic variability analyses. Rapid technological development based on Intelligent Transport Systems (ITS) has popularised the wireless sensor networks (WSN) application. The solution enables continuous monitoring of selected area using multiple wireless and low-cost sensors connected within a network. Those systems are dynamically evolving tools for solving an effective traffic management issues in city centres and urban environments. In the study, authors have performed a traffic variability and its dynamics analysis in a selected area using a multi-sensor network for traffic volume monitoring. The article presents the results of research conducted between years 2015 - 2018 throughout the city of Bielsko-Biala with the support of OnDynamic multimodal system. Within the context of the analyses, basic traffic parameters have been determined and variability trends have been identified on selected road sections. Long-term research indicated the minor variation in a number of vehicle detections and relatively stable traffic volume in the city centre during the analysis period.

Static traffic (parking of vehicles) is one of the most problematic areas of transport in urban areas. In particular, parking areas for heavy freight vehicles in city areas cause problems connected, for example, with insufficient capacity or inadequate equipment. In the Czech Republic the regional concepts for the location of parking lots for trucks have not been developed - rest areas are built mainly on highways. Drivers are forced into other roads to search for alternative parking spaces and thus jeopardize the safety of the cargo to be transported. Because of the lack of such parking areas, drivers are forced to violate the European Agreement Concerning the Work of Crews of Vehicles Engaged in International Road Transport (AETR) or, due to this agreement, to park the truck before the driver’s work shift ends, thereby reducing the efficiency of full driver usage. The paper deals with the issue of rest areas location for road freight vehicles in the selected area. The first part of the paper characterizes variant solutions of parking areas in a particular selected area, which were evaluated on the basis of an analysis of the current conditions. The second part of the paper introduces the evaluation of individual variants using the TOPSIS method, which was chosen as the most appropriate method of multicriteria decision making process.

The article presents the simulation model and simulation experiments aimed at the rationalisation of bottle necks in operations in terms of the capacity utilisation of the material handling equipment, in particular, six conveyance lines. The models and experiments were designed in the Tecnomatix simulation environment which facilitates the modelling of even more complex systems. The simulation model visualises the material flow within the production process comprising individual technological operations and workplaces. The model was used to perform simulation experiments with adjusted production times and added or removed workplaces. The presented article also contains the graphs of the utilised capacity of the machinery and operators. The obtained experimental results suggesting the partial or complete elimination of the accumulation of unfinished products.

Simulation modelling is one way to determine the capacity of railway lines. The specialized software tool OpenTrack was used for simulation. The aim of this paper was to find out whether the OpenTrack simulation software can be used for the calculation of headway, and to compare the results with the methodology of the Railway Infrastructure Administration (SŽDC). Using the software tool, a detailed transport network model can be created including all its important characteristics. The simulation follows the movements and behaviour of trains with predefined parameters on the modelled railway line. OpenTrack allows for monitoring a range of parameters including not only train delays, train conflicts and train traffic flow, but also for instance train energy performance and headways. During the first stage of work with OpenTrack, a simulation model was created, not reflecting any existing infrastructure but including parameters typical of railway lines in the Czech Republic, such as the configuration of gridirons, length of station tracks, size of block sections, etc. This model was subsequently used for the simulation of type train set journeys, and a headway calculator was used for the calculation of headway values. These values were compared with the methodology used by the Railway Infrastructure Administration. The paper is concluded by the comparison of the above mentioned approaches.

NFC (Near Field Communication) devices are used in contactless payment systems, similar to those used in credit cards and electronic ticket smart cards, and they allow a mobile payment to replace or supplement these systems. The trend of increasing the quality of transport services also includes the use of progressive information technologies. The article focuses on the use of NFC technology in regional passenger transport. In the first proposal, the implementation of NFC technology in the form of an electronic wallet in a regional contactless chip card is being considered. In the second proposal we deal with the implementation of NFC technology in regional passenger transport using mobile phones with an active NFC chip. The proposals use Check-In/Check-Out validation, where validators are placed in vehicles. In both proposals it would be possible to create a link to EMV (Europay/MasterCard/VISA) technology, and thus to provide a linking of a contactless smart card, possibly a mobile phone to the passenger’s personal account.

Railway sidings in the Slovak Republic, despite their reduction, still do not lose their importance. In railway transport, a significant part of the realised performances is represented by transport on railway sidings and there is therefore a need to continuously develop and adapt the siding operation to the requirements of the transport market. The reason for the decrease of their number is nowadays mainly the financial demands on the construction of the new siding and its operation. In view of this fact, there are sidings in several companies in the Slovak Republic where the transport performances do not decrease and the performances realised on their railway siding are considered as dominant and economically advantageous. The aim of this paper is based on the analysis of the current state of the siding operation in the selected company in order to solve the problem with insufficient capacity of the siding due to the increase in the volume of processed materials. The problem with the capacity of the analysed siding will be solved through construction-reconstruction measures - namely by construction of a new handling track. This option is a solution to the problem of an insufficient capacity of the siding, which affects the current transport performances and costs of railway wagons staying at stations, too. The proposed measures to support the increase of a siding capacity will be economically evaluated and the pay-back period of these solutions will be assessed.

The introduction of the paper highlights best practice in the area of deploying autonomous trucks in warehouses and the automotive industry, including the current technical possibilities of selected autonomous trucks. The next chapter presents the selected outputs of the scientific project “Center of Excellence for Intelligent Transport Systems” focused on a proposal of the methodology for calculating the necessary number of autonomous trucks and trolleys deployed in logistics warehouses. The methodology is based on the requirement that autonomous trucks do not have downtime. This represents a model solution with possible application in warehouse logistics but also in the automotive industry. The follow-up chapter proposes a methodological procedure to evaluate the efficiency of introducing autonomous trucks to pull trolleys in a logistics warehouse compared to conventional trucks operated by trained personnel. Autonomous trucks can theoretically be operated 365 days and 24 hours depending on the technology of their operation, battery charging, etc. On the other hand, there is generally a shortage of logistics personnel in the European Union as well as reliability and performance have been declining in recent years. The conclusion of the paper includes a discussion of the research results obtained and possibilities for future research.

Remote operations of mobile machinery require reliable and flexible wireless communication. 5G networks will provide ultra-reliable and low latency wireless communications upon whichremote operations, real-time control and data acquisition can be implemented. In this paper we present a demonstration system and first experiments for remote mobile machinery control system utilizing 5G radio and a digital twin with a hardware-in-the-loop development system. Our experimental results indicate that with a suitable edge computing architecture an order of magnitude improvement in delay and jitter over exiting LTE infrastructure can be expected from future 5G networks.

The effect of moisture content and feasibility of its estimation in granular material was investigated via machine vision. The test scheme consisted of saw dust samples derived from Norway spruce with moisture content adjusted to three distinct levels. The effect of moisture when present as ice or liquid water was compared. The experimental procedure consisted of pouring the saw dust under video camera recording. The equipment setup consisted of a vibrator feeder and custom-built pouring frame. Still images were extracted with fixed sample time from the recording done during the pouring procedure. From the extracted frames the dynamic behavior of cone profile was investigated via statistical means. It was observed that 2nd standardized moment correlated with moisture content, phase of water and their interaction. Furthermore, 4th standardized moment correlated with moisture content and phase. The 3rd moment was inspected qualitatively from which it was observed that wet samples exhibited tendency to build mass accumulation sites with increasing moisture content. Samples where water was present as ice this was observed in a very small scale with all moisture content values. Corroborated by optical microscopy, these correlations were deduced to be due to liquid bridging in the bulk. Moisture content when present as ice was, however, observed to have a drastic effect on the overall cone shape. Based on these findings, a machine vision application could be feasible way to estimate moisture content on-line in thawed saw dust by using statistical parameters in classification decision making. This would enable cost-effective on-line monitoring of moisture content and a control circuit to be designed.

The solids content of slurry is typically increased in thickeners. A clean overflow and maximum solids concentration in the underflow are the general targets. The flocculant rate and underflow rate are the two independent variables that are typically used for control. The dependent variables include rake torque, underflow density, overflow turbidity, solids interface level (bed depth), solids inventory (bed pressure), solids settling rate and underflow viscosity. The research problem in question is that the outgoing paste is sometimes difficult to pump. The phenomena leading to this situation are not well known. In the worst-case scenario these phenomena cause clogging in the piping. A data analysis has been done to find the variables that affect and correlate with the pumping problem. The scope of this study covers the measurements from the feed line, thickener and underflow. The goal is to gain better understanding of the phenomena after this phase. The data analysis was done using the paste line pressure difference as a response variable and by dividing the data collected from Yara’s Siilinjärvi mill into two parts: operation areas with high and low pressure difference. The analysis is focused on Thickener 1 due to better availability of measurements. The knowledge of the variables found to influence the pressure difference can be utilized in further development.

This paper considers programming and control of skill-based robots. Robot skills are used to integrate and synchronize robot actions and sensor data in a consistent way. Skill-based approach provides a framework for configurable robot systems, enabling quick setups and start-ups of applications. In the paper we will introduce skill programming and skill control concepts in more detail and how they relate to usage of models and sensors. We will also give a practical example for programming and implementing skills for a grinding application.

Digital Twin (DT) technology is an essential technology related to the Industry 4.0. In engineering education, it is important that the curricula are kept up-to-date. By adopting new digital technologies, such as DT, we can provide new knowledge for students, teachers, and companies. The main aim of this research was to create a course concept to research benefits and barriers of DT technology in engineering education. The research confirmed earlier findings concerning digitalization in engineering education. DT technology can increase motivation for studying and improve learning when applied correctly.

This article presents a statistical prediction model-based intelligent decision support tool for center line deviation monitoring. Data mining methods enable the data driven manufacturing. They also help to understand the manufacturing process and to test different hypotheses. In this study, the original assumption was that the shape of the strip during the hot rolling has a strong effect on the behaviour of the steel strip in Rolling, Annealing and Pickling line (RAP). Our goal is to provide information that enables to react well in advance to strips with challenging shape. In this article, we show that the most critical shape errors arising in hot rolling process will be transferred to critical errors in RAP-line process as well. In addition, our results reveal that the most critical feature characterizes the deviation better than the currently used criterion for rework. The developed model enables the user to understand better the quality of the products, how the process works, and how the quality model predicts and performs.

The integration of the building information modelling (BIM) and assets database has enabled a potential pathway for building stakeholders to add value to the building lifecycle management (BLM) processes. However, the obtaining, storing, processing, and distributing of data have not been ratified in a detailed and semantic manner in any official guideline. This paper suggests a framework for the efficient development of an interoperable visualisation of a building “digital twin” through an intuitive interface, to contribute to the idea above. The framework was applied in two case studies as examples, where rich visualisations of two buildings in the Kanta-Häme region of Finland were constructed using their architectural models and building indoor climate metrics. By constructing an engaging interface, relevant metrics and constant feedback from buildings’ occupants are gathered, meaningful data is selected, processed, and displayed to improve the facility management (FM) process. The yielded result is a progressive web application (PWA), where valuable sets of building performance data are visualised and a promptly communicable channel between owners/occupants and building system is delivered. Further development of this application in practice and research work is also proposed to harness the data-driven monitoring and automation in buildings to the greatest extent.

The main purpose of this paper is to demonstrate the potential of time-domain nuclear magnetic resonance (TD-NMR) technology for monitoring the concentrations of metal ions in water-based solutions. The main focus of this work was paramagnetic ions, such as Mn 2+ , Cu 2+ , Fe 3+ , Fe 2+ , Zn 2+ and Ni 2+ , which are often the principal metal components in mining waters. Laboratory samples of different concentrations of single metals and mixtures of them and samples of real mining water were used in the relaxation rate ( R 2 ) measurements. The measurements of single metal ions were used for the determination of the relaxivities of those ions. The concentrations of the ions in the mining water as a function of pH were also estimated by means of the X-ray fluorescence (XRF) method and ChemEQL software for calculating chemical speciation equilibria. Using these concentration values and the relaxivities of the metal ions, the total relaxation rate ( R 2 ) results were then calculated. Principally, the results of these three different determinations are in relatively good agreement. It can be concluded that TD-NMR has great potential for monitoring metal ion concentrations during water treatment.

Non-metallic inclusions, especially large or clustered inclusions, in steel are usually harmful. Thus, the microscopic analysis of test specimens is an important part of the quality control. This steel purity analysis produces a large amount of individual inclusion information for each test specimen. The interpretation of the results is laborious and the comparison of larger product groups practically impossible. The purpose of this study was to develop an easy-to-use tool for automatic interpretation of the SEM analysis to differentiate clustered and large inclusions information from the manifold individual inclusion information. Because of the large variety of the potential users, the tool needs to be applicable for any steel grade and application, both for liquid and final product specimen, to analyse automatically steel specimen inclusions, especially inclusion clusters, based on the INCA Feature program produced data from SEM/EDS. The developed tool can be used to improve the controlling of the steel purity or for automatic production of new inclusion cluster features that can be utilised further in quality prediction models, for example.

The development of automated work machine systems towards autonomous operation is proceeding rapidly in different industrial sectors. The aim of the study was to explore the current situation and possible differences in standardization supporting the development in different industrial sectors. The existing ISO and IEC standards and work items related to autonomous machinery were reviewed as well as activities in international industry groups regarding automation and autonomy of machinery. In general, the current standards are made mostly for machine manufacturers, but the views or responsibilities at worksite level are not considered. Three different approaches for safety concepts for different operating conditions were identified. One of them relies on onboard safety systems including sensor and perception systems for indoor applications. One guides to separate and isolate the autonomously operating machinery and to use access control to the autonomous operating zone. The third one is relying mainly on the machine operator’s ability to understand the situation and to react correctly according to the available information. From technology point of view there seems to be a gap between the safety requirements set in standards and the state of the art in currently available technology.

Integration of domain expertise and uncertainty processing is increasingly important in automation solutions which rely on data analytics and artificial intelligence. We need a level to assess what is approximately correct. Uncertainties of the inputs are taken into account by using fuzzy numbers as the inputs of different fuzzy and parametric systems. Nonlinear scaling functions ( NSFs ) integrate these solutions and make them easier to tune. Fuzzy rule-based systems are represented with scaled fuzzy inputs. Membership functions ( MFs ) can be developed from NSFs and existing MFs can be used in developing NSFs . Fuzzy set systems and linguistic equation ( LE ) systems become consistent within the limits of detail. In recursive analysis, both meanings and interactions on all levels can be tuned together with genetic algorithms. In applications, the modular overall system consists of similar subsystems, which are normally used, with extensions to fuzzy. The compact fuzzy modules can be developed for specific tasks which are combined within Cyber Physical Systems ( CPS ). Uncertainty processing is embedded in the recursive analysis. The fuzzy extensions provide a feasible way for the sensitivity analysis of the solution.

Digital twins have gained a lot of attention in modern day industry, but practical challenges arise from the requirement of continuous and real-time data integration. The actual physical systems are also exposed to disturbances unknown to the real-time simulation. Therefore, adaptation is required to ensure reliable performance and to improve the usability of digital twins in monitoring and diagnostics. This study proposes a general approach to the real-time adaptation of digital twins based on a mechanism guided by evolutionary optimization. The mechanism evaluates the deviation between the measured state of the real system and the estimated state provided by the model under adaptation. The deviation is minimized by adapting the model input based on the differential evolution algorithm. To test the mechanism, the measured data were generated via simulations based on a physical model of the real system. The estimated data were generated by a surrogate model, namely a simplified version of the physical model. A case study is presented where the adaptation mechanism is applied on the digital twin of a marine thruster. Satisfactory accuracy was achieved in the optimization during continuous adaptation. However, further research is required on the algorithms and hardware to reach the real-time computation requirement.

This paper presents the reliability estimation of fatigue strength of the material used for crank throw components. The material used for crank throw components is forged S34MnV steel and subsequently heat-treated by normalising and tempering. High cycle fatigue testing under fully reversed cycling (R = −1) was performed to determine the fatigue limit of the material. The staircase test method is used to obtain accurate values of the mean fatigue limit stress until a number of cycles up to 1E7 cycles. Subsequently, the fatigue test results depend strongly on the stress step and are evaluated by the Dixon-Mood formula. The values of mean fatigue strength and standard deviation predicted by the staircase method are 282 MPa and 10.6MPa, respectively. Finally, the reliability of the design fatigue strength in some selected probability of failure is calculated. Results indicate that the fatigue strength determined from accelerated staircase test is consistent with conventional fatigue testing. Furthermore, the proposed method can be applied for the determination of fatigue strength and standard deviation for design optimisation of S34MnV steel.

The machinability information of Zr-based bulk metallic glasses (BMGs) are recently limited but essential to provide technological recommendation for the fabrication of the medical devices due to the material’s metastable nature. This study aims to investigate the material removal rate (MRR) and surface roughness under different current and pulse-on time of newly developed Ni- and Cu-free Zr-based BMG using sinking-electrical discharge machining (EDM). By using weightloss calculation, surface roughness test and scanning electron microscopy (SEM) observation on the workpiece after machining, both MRR and surface roughness were obtained to be increased up to 0.594 mm 3 /min and 5.50 μm, respectively, when the higher current was applied. On the other hand, the longer pulse-on time shifted the R a into the higher value but lower the MRR value to only 0.183 mm 3 /min at 150 μs. Contrary, the surface hardness value was enhanced by both higher current and pulse-on time applied during machining indicating different level of structural change after high-temperature spark exposure on the BMG surface. These phenomena are strongly related to the surface evaporation which characterize the formation of crater and recast layer in various thicknesses and morphologies as well as the crystallization under the different discharge energy and exposure time.

The dynamic behavior of a partially debonded Ferry Ro-Ro’s sandwich car deck is investigated by using commercial finite element software ABAQUS. Debonding in the car deck model is estimated by comparing the dynamic responses of the fully intact and damaged model of the bonding condition. The influence of the debonding ratio is investigated by free vibration analysis using Lanczos iteration method. The dynamic response of the car deck model is loaded with harmonic excitation and is examined in detail. The transverse displacements, velocities, accelerations, longitudinal strains, and phase portraits are investigated in the central point of the damaged area. To evaluate the effect of inserting the spring contact element during the dynamic analysis, both debonded models with and without spring contact elements are examined. From the report, it can be concluded that the dynamic analysis which relies on the modal analysis can be used to diagnose the possibility of debonding problem in the car deck structure. The natural frequencies of the debonded model decrease due to the presence of discontinuity in the debonded region. Further, the discontinuity also creates locally concentrated deformation and significantly affects the short-term time response.

The sandwich plate can be used to replace the conventional steel stiffened plates on the ship’s hull structure. By using the sandwich plate, not only the stiffness of the plate can be increased but also the overall ship weight can be reduced, as well as the ship payload can be increased. The sandwich plate should be accompanied by the damage identification system to prevent ship structural failure. In this paper, the global damage identification method, which is based on the vibration analysis, is investigated. For that purpose, the vibration-based damage identification using the Finite Element Method (FEM) is explored. The variables being investigated are the damage sizes, damage locations, and the boundary conditions which affect the natural frequencies of the structures. The sandwich plate considered in this study consisted of steel faceplates with the polyurethane elastomer core, which has been checked to meet Lloyd’s register, an international maritime standard. From the analysis, it is found that the fully clamped boundary conditions accompanied by high vibration modes are more sensitive to the presence of artificial damage. The changes in the natural frequencies can be used as a reference to identify the size and location of damage in the sandwich plate.

This paper investigates the influence of T6 post-weld heat treatment (PWHT), and welding orientation on the strength and microstructure of tungsten inert gas (TIG) welded AL6061 aluminum alloy. The TIG process was used to weld the AL6061 at the transversal and longitudinal orientations with reference to the rolling direction. The T6-PWHT is a two-phase heat treatment process, and was applied to AL6061 in order to increase its strength. This T6 was carried out under three different artificial aging; 8, 18, and 24 hours. The influence of PWHT and welding orientation on the strength of AL6061-T6 were investigated through a series of tensile and microhardness tests. In addition, the microstructure observations were performed using the optical and scanning electron microscopes. It was established that the strength and microstructural characteristics of AL6061 are significantly dependent on the T6 artificial aging. Accordingly, the improvements in the strength and ductility were mainly contributed by the grain growth and subsequent precipitate strengthening. Moreover, the welding orientation only affects their fracture surfaces and locations after tensile testing.

Nozzle hole diameter of 3D printer (3DP) can be varied to obtain required product quality as well as to reduce manufacturing times. The use of larger diameter may accelerate manufacturing times of products, yet the product quality, including the mechanical properties, still needs to be investigated profoundly. The purpose of this work is to investigate experimentally the effect of nozzle hole diameter of 3DP to the surface quality, accuracy, and the strength of the product. The specimens were manufactured by fused deposition modelling (FDM) 3D printing using polylactic acid (PLA) as the filaments.Bed temperature, extruder temperature and printing speed were set to be 60 ∘ C, 200 ∘ C and 80 mm/s respectively. The thickness of each layer was set at the ratio of 20% to the nozzle hole diameter. Infill pattern was determined by using line type of 100%. Nozzle hole diameter of 0.3, 0.4, 0.5 and 0.6mmwas compared in thiswork. The results show that bigger nozzle hole diameter enhanced the density and tensile strength of the products thought it was not linearly correlation.

Hip joint is an important human joints system. The damaged hip joints need to be replaced with artificial hip joints. The Study of the hip joint is very costly therefore another calculation method is demanded to produce good result in acceptable time and cost. Considering this problem, a series of study to assess hip joint performance is conducted using numerical approach. Important parameter for example applied materials are used in the modelling by idealizing Ti-6Al-4V compared to SS 316 L, and stemlengthwas chosen to be 128 mm. ANSYS software was used to analyze models, and designed element size variations were set to be in range 1 to 2.5 mm. The magnitude of force was placed on the femoral head with an angle of 16 ∘ C from the vertical axis. Results showed that SS 316 L material has smaller deformation than Ti material. Whereas Central Processing (CP) time decreases in increasing element size for both materials. In addition, more variations in mesh size are needed to get more accurate convergent results.

Indonesia has the abundant potential of hydropower but not yet processed optimally, which intensely depends on fossil fuel. Hydropower installed in Indonesia is only 11,272 MW, from the estimated potential approximately 94,476 MW. This data shows that 89% of the hydropower potential in Indonesia has not been processed. One of the present efforts to utilize this resource is addressed to develop the Savonius water turbine. Conventional water Savonius turbines have a comprehensible structure and easy to be applied. However, the turbines produce relatively small power, which requires further assessment to improve its performance. The current study is performed by considering geometric changes on the water Savonius turbine to observe their effect on power characteristics. Considered changes are made on the number of stages, and the angle between stages, specifically a single-stage, two-stage 0°, Two-stage 90°, three-stage 0°, and three Stage 120°. The research was carried out by designing simulation model using ANSYS software with CFX Solver. Water speed is determined to 0.8 m/s, while plates with 110 mm in diameter and 110 mm in height are incorporated as rotor configuration. Based on this study, it can be concluded that the addition of the stage affected improving the performance of the Savonius water turbine, where the multi-stage turbine experienced an increment compared to conventional water turbines. The interesting tendency was found on the two-stage rotors with angle of 0° which produced a smaller Cpmax compared to the conventional water Savonius turbines.

The article presents the results of shear and tensile strength of deformable cement adhesives, reinforced by fiberglass mesh with a different weight in a lightweight floor system without screeds. The substrate under adhesive was EPS and XPS thermal insulation. Tests were carried out in dry, wet conditions as well as during freezing and thawing. On their basis, it can be concluded that the larger contact surface of the EPS thermal insulation with the deformable adhesive C2S1 increases the adhesive’s tensile strength. This surface is not important using C2S2 adhesives or when the substrate is made from rough insulation XPS. It was generally found that the higher weight of the fibreglass mesh in deformable cement adhesives has a more favorable effect on their shear strength. Water absorption does not significantly affect the adhesion of terracotta, and in some configurations of components in this system increases it. The adhesive with the symbol C2S2 compared to C2S1 has a higher tensile and shear strength using the same materials. Frost conditions do not allow for long-term use of this type of floor construction in snow and ice protection systems. This experimental research shows that an economical solution with optimal strength consists of XPS insulation, 205 g/m 2 mesh, C2S1 adhesive.

Designing masonry structures or any other structures involves ensuring an adequate level of safety. This is done by applying the appropriate set of partial factor for strength and partial factors for actions in accordance with the recommendations of the Eurocodes. The paper presents an analysis of the reliability of a compressive masonry structure on the example of a wall fragment made of silicate blocks. The relationship between partial factors applied to actions in various configurations and factors for the compressive strength of masonry was investigated. The analyses consisted in determining the reliability index β using the First Order Reliability Method (FORM). The results are presented in diagrams with reference to different construction classes execution of works, as well as different reliability classes from RC1 to RC3.

This paper is concerned with early cost estimation of sport facilities. Sufficiently precise cost estimation is essential for investors in the pre-investment stage where they decide on whether to pursue an investment and choose a suitable technical solution for the development of the project. Through a detailed analysis of the technical and economic documentation pertaining to seven sport facilities projects assembled using concrete prefabricated beam parts, as well as evaluation of the data thus obtained, three types of technical-economic indicators were set in relation to the enclosed building area, the number of spectator seats and the sports playing area. The results achieved indicate that evaluation of relations between these three indicators could contribute to a more effective use of investment funding on the part of the investor. Other conclusions include the finding that available indicators published by private companies active in the area of construction budgeting are not sufficiently accurate for the purposes of investment decision-making; specifically, these indicators greatly overestimate the costs of sport facilities, which can potentially lead to these projects being rejected. This contribution brings know-how for a more accurate early cost estimation of sport facilities in the Czech Republic which can, thanks to a generally applicable methodology, be used in other countries as well.

This paper describes a small single-span integral bridge made of in-situ concrete. The bridge was designed by the author and built on the M9 motorway between the towns of Waterford and Kilcullen in Ireland. Selected parts of the bridge design are presented. First the principles of modelling and designing integral bridges and culverts are explained. Then the considered bridge’s design is described. The advantages and disadvantages of such structures are discussed. The focus is on the design, construction, cost and in-service behaviour of small integral bridges and culverts. In Conclusions the author shares his knowledge and experience relating to the design of small integral bridges and culverts and puts forward recommendations as to further research on this type of structures in Poland.

In order to correctly model the behaviour of a building under load, it is necessary to take into account the displacement of the subsoil under the foundations. The subsoil is a material with typically non-linear behaviour. This paper presents an example of the modelling of a tall, 14-storey, building located in Lublin. The building was constructed on loess subsoil, with the use of a base slab. The subsoil lying directly beneath the foundations was described using the Modified Cam-Clay model, while the linear elastic perfectly plastic model with the Coulomb-Mohr failure criterion was used for the deeper subsoil. The parameters of the subsoil model were derived on the basis of the results of CPT soundings and laboratory oedometer tests. In numerical FEM analyses, the floors of the building were added in subsequent calculation steps, simulating the actual process of building construction. The results of the calculations involved the displacements taken in the subsequent calculation steps, which were compared with the displacements of 14 geodetic benchmarks placed in the slab.

Connections made by self-drilling screws are often used in steel cold-formed structures and sheeting. Their structural properties, such as resistance, flexibility and ductility are obtained by testing under monotonically increasing loading and can influence on overall behaviour of structures. This paper presents results of experimental study how variable load deteriorates those structural properties of lap shear connections with self-drilling screws. One monotonic and four variable loading histories were utilized, with displacement and force control. Applied loading histories were aimed to simulate persistent design situation, which referred to the conditions of normal use according to EN 1990. Deterioration of resistance and flexibility have been assessed for each variable loading history. It was observed that resistance deterioration is directly proportional to loading range. In case of flexibility, at small displacement range connectors become stiffer. Degradation of flexibility starts to increase at larger displacement range.

The article presents concept of II generation N type RHS plug & play truss connection made in non-welded technology. Three connections of the representative truss are analyzed. Resistance calculations of these truss joints, using the component method, are shown. Test results and the theoretical resistance of these connections are compared.

The article presents comparative analyzes aimed at determining the optimal cross-section used in cold-formed steel purlins. The geometrical characteristics, bending resistance and self-weight of channel, zeta and hat cross-sections were compared. The calculations were made using Dlubal SHAPE-THIN software for the bending by the main axis y-y and z-z. The characteristics for the gross and effective cross-section were determined. Based on the first stage analyzes, a significant decrease in cross-sectional bending resistant was observed as a result of a local buckling. The solution to this problem may be the use of intermediate stiffeners. In the second stage, analysis of the impact of the intermediate stiffeners’ locations on the characteristics of hat sections were conducted. Additional intermediate stiffeners on the webs, on the upper chord, and on the webs and upper chord (together) were considered. A significant effect on the bending resistant with a small increase in the element’s self-weight has been demonstrated. In the third stage, the characteristics of a channel, zeta and hat profile with intermediate longitudinal stiffener in the middle of the web were compared. The performed analyzes demonstrated that the hat cross-section shows a significant advantage in bending by the main axis z-z. This advantage can be used in case of lack of protection against lateral torsional buckling and a larger degree of roof slope.

Floating geosynthetic encased columns (GEC) are an increasingly popular method of strengthening weak subsoil. Design of floating columns is a difficult and not fully recognized issue. This paper treats the floating GEC column as a special kind of “pile” and its bearing capacity is calculated using five selected methods for calculating the bearing capacity of piles based on CPTU penetration tests. The calculations were done on the basis of insitu tests carried out on one of the sections of the Bargłów Kościelny bypass. The paper contains a comparison of the bearing capacities of floating GEC columns calculated with different methods based on CPTU penetration tests.

The paper estimated the effect of the distribution of edge and shear stresses occurring in the façade texture layer of three-layer walls of large slab panel buildings, as well as the variability of these stresses depending on the anchorage strength of the anchorage. Bonded anchors with seven different diameters M8 ÷ M30, selected based on catalogues, were analysed. The traction stress was determined based on the destructive force, which is determined by the catalogues of manufacturers of bonded anchors. Depending on the choice of the method of repairing the connections between the textured layer and the structural layer, we give the three-layer walls a new character of work. One of the methods of strengthening the textured layer is the popular COPY-ECO system in Poland. It is a system of two anchors (horizontal and diagonal), reflecting the shape of the work of existing hangers. The article also analyses the variants of oblique anchorages for the M12 anchor with inclination angles of 30 ∘ , 45 ∘ and 60 ∘ . The extent to which the anchorage inclination angle has been assessed influences the higher parameters of the anchor’s bearing capacity due to the shearing of the textured layer.

The beginning of each construction investment is preceded by proper preparation. In the case of public procurement, this usually involves conducting a tender procedure to select a contractor for the works.Railway construction works require this rigor. This article will provide an overview of railway construction investments planned to be implemented in the current EU financial perspective. The key elements of the tender process related to individual stages of the tender will be analyzed.

Laser surface texturing is currently the most developed technique for producing fully reproducible microcavities on the surfaces of machine elements. From the point of view of texture technology, an important aspect is the proper selection of process parameters to obtain texture elements with desirable and repetitive geometries and physicochemical properties. Surface texturing improves mottling and fretting resistance and is also used wherever the adhesion properties of surface layers (printing techniques, bonding materials, biological and chemical activity, coatings, etc.) are important. The article shows the possibility of applying statistical functions to the selection of appropriate machining parameters to obtain microgeometry useful in the application of textured surfaces [1].

Paper presents results of laser additive manufacturing. Deposition of nickel based super alloy Inconel 625 was performed. Laser metal deposition is advanced manufacturing process dedicated for prototyping and low scale series production. Inconel 625 is nickel based super alloy, with high heat resistance properties. Therefore due material properties and chemical composition is characterized as a difficult to machining [1, 2]. Additive manufacturing process using focused photons beam for selective deposition of metallic powder in laser engineered net shaping (LENS) method can be used as alternative technology. High energy density of controllable laser beam combining with coaxial delivery system allow to precise deposited metallic powder. Manufacturing process are based on selective melting of additional material using laser radiation and crystallization process. An additional material in form of filler wire as well as metallic powder can be used. Advantages of using metallic powder are higher level of process control, nevertheless adequate selection of process parameters are required. High energy density of laser beam and rapid crystallization process affect on metallographic structure of deposited material. Thermal energy absorbed in material affect on phase transformation.Molten powder mixing with base material changing metallographic structure. Chemical composition of obtained overlay weld are combination of base and additive material. Therefore to achieve stable crystallization process chemical composition of additive material wassimilar to base material. Additional alloying elements could affect on mechanical properties. Deposition process using TruLaserCell 1005 laser machine was performed. To determine properties of manufactured material metallographic analysis and destructive tests were performed.

Numerical simulation of laser welding dissimilar joint was presented. Results of butt joint for low carbon and austenitic steels are studied. Numerical calculations based on thermo-mechanical method and phase transformation were used for estimating weld dimensions and joint properties. Unconventional welding method where focused photons beam are used as a heat source were presented. Problems with welding of dissimilar joints, where different composition and thermo physical material properties affect on this phenomena complexity are solved using numerical methods and laser welding technology. Simulation of low carbon and stainless steel joints using SimufactWelding software are presented. Model of heat source within geometry and parameters was programmed. Laser beam welding simulation was performed for estimating parameters for complete joints penetration. Programming welding boundary condition and heat source geometry welding parameters with output power and welding speed rate was estimated. Materials used in simulation process and experimental welding was low carbon construction S235JR and stainless 316L steels in sheets form. Joint properties such as fusion zone and heat affected zones dimensions and stress-strain distribution were calculated. Estimation of complete joint characteristics was obtained using thermo-mechanical simulation method and Marc solver engine.. Experimental trial butt joint welding were performed based on estimated parameters. Welding process was performed using 6kW CO 2 laser system. Based on numerical simulation, microstructure analysis, hardness distribution and chemical distribution of fusion zone, properties of obtained joint was studied. Model for simulation of dissimilar laser welding joint was obtained, and properties of obtained joint based on simulation and experiment was studied.

The paper presents the results of tests on the geometric structure of the surface, hardness and tribological tests of coatings produced by the method of physical vapor deposition (PVD) on the Ti13Nb13Zr alloy. Hardness was determined using MCT 3 from Anton Paar, by instrumental indentation. A diamond indenter with Berkovich geometry was used for the measurement.Model tribological tests were carried out in reciprocating motion under conditions of technically dry friction, friction with lubrication of synovial fluid and Ringer’s solution. The counter-sample in the tested friction nodes was a ball of Al 2 O 3 with a diameter of 6 mm. Nanometer hardness measurements showed that as a result of the diamond-like carbon coating (DLC), the hardness increased by an 7-fold. The lowest friction coefficients among all tested friction nodes were obtained for the material combination Ti13Nb13Zr a-C:H - Al 2 O 3 regardless of the conditions of testing. In the case of technically dry friction, the coefficient of friction decreased by 80%, synovial fluid by 70%, and in the case of Ringer’s solution by 88% compared to the results obtained for Ti13Nb13Zr.

In the paper the numerical analysis of the stress fields for 145Cr6 steel, near crack tip is presented, based on three-dimensional finite element method (FEM) analysis. The FEM analysis is focused on SEN(B) specimens with relative crack length a / W ≈ 0.30. In addition to the presentation of the normal components of the stress tensor, the paper presents selected measures of stress triaxiality parameters, measured for the value of the J -integral, corresponding to the experimentally determined fracture toughness, denoted as J IC , which is considered to be a material constant or material characteristic [1, 2]. Presented topic is a continuation of papers [3, 4],whichwere based on experimental analysis, presented in [5].

Contemporary production companies operate in a dynamically changing environment and try to strengthen their competitive position. Therefore they take action acting at implementing new ones as well as improving and maintaining existing production processes, using for this purpose knowledge and available tools and methods. For dominant activities undertaken in the scope of improving and maintaining production the pro-quality activities can be included. Quality mainly depends on the efficiency of production processes, therefore manufacturing companies should focus their activities on maintaining and improving them. The methods of technical risk analysis and assessment are effective methods of maintaining production processes, whose application makes it possible to indicate any deviations from accepted standards. Analysis and assessment of the technical risk of the production process makes it possible not only to indicate non-conformities identified in the process, but mainly taking corrective actions. The aim of the article is to formulate of the method used to identify and assessment of the technical risk of the cutting process on the organizational side. The method has qualitative-quantitative type, and is the effective tools for technical risk assessment necessary to maintain the production process. It is assumed that the quality of the cutting process is ensured by the technical condition of the machine.

The purpose of the experiment was to study the influence of the laser beam in pulse mode on metallic foils in order to obtain a spot weld. The welding process was carried out using the overlap weld method, using spot welds in various quantities. The Nd - YAG BLS 720 pulsed laser was used to conduct the experiment. The impact of the number of spot welds on the value of force needed to break the sample was examined. A number of measurements were carried out to determine the best process parameters. Butt welding and overlap welding were also performed using a continuous weld consisting of spot welds. Weld strength tests were performed to select the most appropriate parameters for the process under consideration.

This article presents a test stand used to determine the angle control of a pair of pneumatic artificial muscles PAM, which work antagonistically like natural muscles, e.g. in the human arm. The muscles were designed and produced at the Kielce University of Technology. The technical and functional parameters of the muscles were determined on the basis of experimental research. The Ziegler-Nichols method of tuning a PID controller on the basis of the step response measurement of the open system is also presented for the analysed problem. Experimental research was performed on angle control of a pair of pneumatic muscles with a PID controller.

The purpose of the study was to evaluate the properties of diamond-like carbon DLC coatings with ionic liquids and cutting fluid containing zinc aspartate used as lubricants. The DLC coatings (a–C:H) were deposited onto the 100Cr6 steel substrate by physical vapour deposition PVD. The surface morphology testing, cross section and chemical composition analyses of the DLC coatings were performed using the scanning electron microscope, equipped with an EDS microanalyzer. Surface geometry measurements prior to and after tribological tests were performed on a confocal microscope with interferometry. The tribological tests were carried out on an Anton Paar TRB3 tribometer under technically dry friction and lubricated conditions with an ionic liquid, trihexyltetradecylphosphonium bis (trifluoromethylsulfonyl) imide and 1–butyl– 3–methylimidazolium bis (trifluoromethylsulfonyl) imide and cutting fluid with zinc aspartate. The results show that DLC coatings and ionic liquids can significantly reduce resistance to motion.

The article presents the problem of planning the laser beam trajectory for the laser micromachining process. The article concerns on the ablative laser micromachining issues. Different effects of laser beam trajectory on pocket geometry in laser micromachining were investigated. The results of experimental tests are presented. Based on the research, potential causes of different effects of the laser beam for various trajectories were formulated. Several different types of trajectories for the assumed shape were developed for the purposes of the research. Laser micromachining was performed with fixed parameters of the laser device using different trajectories. The article indicates the significant impact of the laser beam trajectory on the effect of interaction on matter during the laser milling process, which is not often mentioned in scientific reports. The article presents the basic geometrical measurements indicating the need to determine the leading of the laser beam. Studieswere conducted using the microscopic observation methods and interferometric methods for estimating the surface condition. The article indicates the need for extensive research focusing on the mechanism of the impact of the laser beam scan strategy on the effect on the material during ablative laser machining. The article summarizes the analysis and discussion of research results.

The qualified human resources with high competitiveness and employability skills are needed to face the era of technological disruption, but employers find a lack of expertise among job seekers. Insufficient skills are related to the issue of education quality. This study aims to identify the employers’ employability skills needed in the career field and the way to integrate it into the instructional process. The research was conducted through Systematic Literature Review (SLR) and mapping approach that consisted of three stages: planning, conducting, and reporting. The literature reviews in this research were derived from Science direct, Springer and IEEE as the main references. The results from the analysis in the literature review showed that employability skills are needed in relation to the work demands in the future according to the employers covering communication, team working, problem solving, and technological skills. The implementation of employability skills in the instructional process is to integrate them into the classroom for all subjects.

Aim of the study is to implement Geomatics learning innovations by applying the scaffolding Problem-Based Learning integrated model to improve the student’s Vocational HOTS. The method applied was qualitative with the participation of 2 groups of students practicing consisting of 4 people each. The level of cognitive mastery was measured with the Bloom taxonomy (C1-C6). The results of the investigation showed that the integrated model effectively formed students’ Vocational HOT Skill as a group in 3 stages. The first stage of learning focused on mastering the operation of equipment needed in practice (C2-C3 and partly C4). In the second stage, the students have mastered most of the cognitive analysis and accuracy of practical data (C4-C5) and in the third stage, they made practiced steps more effectively and successfully correlated to the Indonesian National Standards (SNI) level (C6) at the moderately accurate. The application of the Scaffolding Problem-Based Learning model has a positive impact that students get21st-century learning with the main characteristics (4C), consisting: Communication, Collaboration, (Critical thinking, and problem-solving), and Creative thinking. Learning outcomes enriched with higher-order thinking skills can be seen when students take advanced Geomatics material, They already work with groups to map the area more independently

An alignment between technology and teachers is required to attain a successful integration of technology in the learning process. This alignment should be started at the teacher training program. This article outlines how the literature points toward Project-Based Learning (PBL) with technology integration in pre-service teacher education. The literature review focuses on describing how technology integrated with project-based learning along with the investigation of what influencing the successfulness on PBL’s implementation by integration of technology. The five steps on Systematic literature reviews (SLR) are chosen as a systematic approach for reviewing the literature. Based on the defined inclusion and exclusion criteria, 16 technology integration in PBL studies published between January 2015 and July 2019 was remained and selected to be investigated further. Analysis of the selected studies revealed that the most popular technology integrated with PBL was social media, following by a learning management system. The teacher’s ability to give guidance during the learning process is the most influential factor for the success of technology integration in PBL.

Bamboo laminate composites could be the alternative materials in outdoor application. However, the life time prediction of this composite in humid environment became a concern considering hydrophilic property of the bamboo fibre. This research aimed to assess the changes of mechanical properties in the composite with the sorption of water. It employed hand lay-up method in developing the laminate composites with epoxy as the matrix and woven bamboo as the reinforced material. Water sorption characteristic was evaluated through a gravimetric analysis for different water immersion temperatures. The sorption on water was studied by four weeks immersion in room temperature as well as in elevated temperatures of 50 ∘ and 80 ∘ C. Tensile test was performed to evaluate the mechanical properties of the composite. This research clearly showed the significant effect of bamboo fibre on the strength and water sorption behaviour of the composites. It was observed that the rate of water absorption depends on temperature of immersion. Larger debonding between the bamboo fibre and the epoxy matrix was found in higher water immersion temperature. The results of this study emphasized the importance of considering the deterioration of mechanical properties in outdoor applications of bamboo composite highly exposed to high temperature and humidity

There have been some hindrances in the process of programming learning. An adaptive learning system, such as ELaC, Java Guide, and Java Grader provides an adaptable learning content that can accommodate the learning styles as well as preferences of each learning individual. Moreover, an adaptive learning system can help students of different capabilities in learning programming. This study examined the outcomes of the implementation of an adaptive learning system in programming learning, as well as some finding results that were conducted according to the Systematic Literature Review framework. The research questions of this research were: problems faced during learning of programming as a background of system development, advantages and disadvantages of the system characteristics, technology, features, and effectiveness of the developed adaptive learning system. This research produced concepts that are summed up upon the related resources. The results of this study summarized whether the use of adaptive learning systems in learning programming could overcome the problems encountered during the learning process.

Analysing the Output Power of a Solar Photo-voltaic System at the design stage and at the same time predicting the performance of solar PV System under different weather condition is a primary work i.e . to be carried out before any installation. Due to large penetration of solar Photovoltaic system into the traditional grid and increase in the construction of smart grid, now it is required to inject a very clean and economic power into the grid so that grid disturbance can be avoided. The level of solar Power that can be generated by a solar photovoltaic system depends upon the environment in which it is operated and two other important factor like the amount of solar insolation and temperature. As these two factors are intermittent in nature hence forecasting the output of solar photovoltaic system is the most difficult work. In this paper a comparative analysis of different solar photovoltaic forecasting method were presented. A MATLAB Simulink model based on Real time data which were collected from Odisha (20.9517 ∘ N, 85.0985 ∘ E), India. were used in the model for forecasting performance of solar photovoltaic system.

The importance of learning style in student’s learning performance has been gaining scholar’s attention since it was coined in the early 70s. Atmatzidou’s robotics procedure of a five-stages robotic activities was deployed in the research. This study adopts a case study research design for gathering and analyzing data as the case research allows the exploration of unforeseen phenomena and offers insights into the interdependencies among components revealed in the study. This research introduces the use of Lego Mindstorm as the mean of pro-filing a student’s behavioral patterns. Student’s behavior patterns, then, mapped into radar charts to present the extent of both Kolb and science, technology, engineering, and math (STEM)’s profile of student’s learning style categories. The paper contributes to theory by extending Kolb’s Learning Style instrument by mapping the pattern of learning styles identified in the research and exploring students learning experience. Dominant four-domain-indicators captured during the activities characterize Students’ learning profiles. While the Kolb Learning Style and its instrument are considered classic in hands-on literature, the use of educational robotics to elaborate students’ learning style is novel in the literature that may affect the delivery of non-technology subjects in the curricula.