Abstract
Radiation has been used in a variety of different fields since its discovery. It is very important in medial sector for both diagnosis and also for treatment. In this study, the radiation dose rate emitted to the environment after radiopharmaceutical injection was determined using patients undergoing bone scintigraphy imaging. Radiation dose rate measurements were performed at different distances from the patient and at different levels of the patient. Measurements were done at different times to determine the relationship between radiation dose rate and time. The radiation dose rate emitted by the patient was measured after an average of 10.21, 42.36, and 76.28 min of injection. In order to see the relationship between radiation dose rate and distance, measurements were done at 25, 50, 100, and 200 cm distance from the patient. The measured average radiation dose rate at 1 m distance from the patients’ chest level and 10.21 min after radiopharmaceutical injection was 16.27 μSv h−1. Then, the average radiation dose rate decayed down to 13.65 μSv h−1 after 42.36 min, while the measured average radiation dose rate after 76.28 min was lower as 12.41 μSv h−1 at 100 cm from patient’s chest level.
1 Introduction
Human beings are exposed to natural and artificial radiation throughout their lives. One of the areas where artificial radiation is used is medical applications. Determination of radiation concentration in medical applications is very important for both patients and healthcare workers. Some international organizations have set limits for radiation concentrations that people may be exposed to. It is important for public health that radiation levels in medical applications remain within the recommended limits [1,2,3].
Radiation effects are of two parts, the definitive deterministic effect and the uncertain stochastic effect. Deterministic effects are the result of high-dose radiation exposure to large body areas. There is a threshold dose value in the deterministic effect formation and the effect increases proportionally with the dose. As a result of this effect, acute radiation syndrome, radiation burns, fibrosis, necrosis, and sclerosis may emerge as late results. Stochastic effects are caused by prolonged exposure to low radiation doses and there is no specific threshold dose value [4].
Bone is in the process of continuous shaping throughout life. Physiological units in bone formation and shaping are osteocytes, osteoblasts, and osteoclasts. Osteoblasts are bone-forming cells. Osteoblasts secrete osteoid which is the main substance of bone. Osteocytes are cells that fill cavities in the bone tissue called lacun. Osteoclasts are separated from hemopoietic progenitor cells. Osteoclasts are specialized macrophages that become powerful phagocytic cells capable of bone resorption in new matrix regions made by osteoblasts [5]. Advanced cancers often metastasize to bone [6]. Bone metastases are most commonly involved in the axial skeleton. The axial skeleton provides a favorable medium for tumor growth due to the large bone marrow, large capillary network, and slow blood flow [7].
Technetium-99m-methylene diphosphonate (Tc-99m MDP) is the most commonly used radiopharmaceutical in bone scintigraphy. Ion exchange occurs between phosphate groups on the surface of the bone matrix and phosphate groups of Tc-99m MDP. Tc-99m is the most widely used radioisotope in nuclear medicine with a half-life of 6 h and emits 140 keV of gamma photons [8].
In this study, static bone scintigraphy was applied on patients with a history of cancer to detect bone metastases. The anamnesis of the patients who apply to the clinic for static bone scintigraphy is first taken. After the anamnesis, the radiopharmaceutical (Tc-99m MDP) prepared in the nuclear medicine laboratory is injected into the patient intravenously. In bone scintigraphy imaging, adult patients are injected intravenously with 20–30 mCi (740–1,110 MBq) radiopharmaceutical (Tc-99m MDP).
While the prepared radiopharmaceutical is applied to the patient, the employees wear a lead apron and inject with the injectors in the lead shield. The patient is taken to the radioactive waiting room within the framework of time, distance, and shielding measures, which are three important factors in radiation protection. Patients are kept in the radioactive waiting room for 1.5–2 h for better retention of Tc-99m radioactivity. The accompanying relatives of the patient are kept outside the room. Meanwhile, the patient is given 2 L of water. The patients drinking water is important for the involvement of the radiopharmaceutical. The patient waiting for a minimum of 1.5 h is told to empty his bladder and then the patient is taken to the imaging room. After administering the radiopharmaceutical, it is important that the patient be kept as far as possible from healthcare professionals and other patients during waiting, imaging, and after imaging. In addition, using lead shielding will cause employees to be affected by less radiation.
Radiation exposure hazards are regulated by the International commission on radiological protection (ICRP). ICRP recommended a radiation dose rate of 20 μSv h−1 at a distance of 1 m from the patient to allow patients to be discharged after radionuclide treatment [9]. Therefore, it is really important to investigate the concentration of radiation emitted from the patient and the expected dose rate after radiopharmaceutical injection in nuclear medicine.
Some studies have been carried out on the radiation doses emitted to the environment after different radiopharmaceuticals were injected to the patients. In these studies, usually the doses they emit into the environment after FDG injection were examined.
Sometimes, patients injected with radiopharmaceuticals do not know the exact time and distance of approaching other people. The main motivation of this study is to determine the time and distance that can be approached to the patient emitting radiation. This time and distance are very important especially for the relatives of the patients.
The main purpose of this study was to determine the radiation dose rate emitted by patients undergoing bone scintigraphy. The radiation dose rate emitted by the patient varies with time and distance from the patient. In order to determine the change in radiation dose rate over time and distance, measurements were done after different periods of radiopharmaceutical injection and at different distances from the patient.
2 Materials and methods
This study was carried out in Istanbul Dr Lutfu Kırdar City Hospital, Nuclear Medicine Department. The study was conducted on 25 people (13 females and 12 males) whose ages ranged from 38 to 92 years (mean 60.33 years). The weight of the participants ranged from 49 to 130 kg, with an average of 75.78 kg .
Patients were first injected with radiopharmaceuticals by weight. The radioactivity given to patients ranged from 17.23 mCi (637.51 MBq) to 20.58 mCi (761.46 MBq), with an average of 19.06 mCi (705.22 MBq). Immediately after radiopharmaceutical injection, patients began to emit radiation around them.
Patients undergoing bone scintigraphy imaging were used to calculate the external radiation dose rate after radiopharmaceutical injection in this investigation. Radiation dose rates were measured from a variety of angles and at a variety of distances from the patient. For this study, we took readings at various intervals to establish a time–dosimetry relationship for the radiation dosage rate. After an average of 10.21, 42.36, and 76.28 min post-injection, the patient’s radiation dosage rate was measured. Experiments were performed at 25, 50, 100, and 200 cm from the patient to determine the dose rate as a function of distance.
The radiation dose rate emitted by the patient was measured after an average of 10.21, 42.36, and 76.28 min after injection. In order to determine the relationship between radiation dose rate and distance, measurements were done at 25 cm distance, 50 cm distance, 100 cm distance, and 200 cm distance from the patient (Figure 1). As shown in Figure 1, the measurement places are labelled as HL-25 which is 25 cm distance from patient’s head level, HL-50 is 50 cm distance from patient’s head level, HL-100 is 100 cm distance from patient’s head level, HL-200 is 200 cm distance from patient’s head level, CL-25 is 25 cm distance from patient’s chest level, CL-50 is 50 cm distance from patient’s chest level, CL-100 is 100 cm distance from patient’s chest level, CL-200 is 200 cm distance from patient’s chest level, FL-25 is 25 cm distance from patient’s foot level, FL-50 is 50 cm distance from patient’s foot level, FL-100 is 100 cm distance from patient’s foot level, and FL-200 is 200 cm distance from patient’s foot level.

Locations of measurements performed on human body.
Radiation rate measurements at the head level were done at 25, 50, 100, and 200 cm distances from the patient’s head level. Radiation rate measurements at the chest level were done at 25, 50, 100, and 200 cm distances from the patient’s chest level. Radiation rate measurements at the foot level were done at 25, 50, 100, and 200 cm distances from the patient’s foot level. Thus, the radiation dose rate was determined from 12 different points around the patient. Radiation dose rate measurements were performed using the GM (Inspector Nuclear Radiation Monitor Deluxe Dose Rate CPT.5250-0047) detector which was calibrated by Turkey Atomic Energy Agency.
3 Results and discussion
The average radiation dose rate at 25, 50, 100, and 200 cm from the patient’s head level is shown in Table 1. The average radiation dose rate measured at 1 m distance from the patients’ head level and 10.21 min after radiopharmaceutical injection was 14.56 μSv h−1 (range 8.26–19.17). Then, the average radiation dose rate decayed down to 12.89 μSv h−1 (range 8.13–17.43) after 42.36 min, while the measured average radiation dose rate after 76.28 min was lower at 10.72 μSv h−1 (range 5.37–15.67) at 100 cm from patient’s head level.
Radiation dose rates at patient’s head level at different distances and at different times after injection
Distance from patient (cm) | Time after the injection (min) | Dose rate range (μSv h−1) | Mean dose rate (μSv h−1) | Normalized mean dose rate (μSv h−1 MBq−1) |
---|---|---|---|---|
25 | 10.21 | 45.16–140.23 | 68.11 | 0.0966 |
42.36 | 24.67–90.35 | 53.27 | 0.0755 | |
76.28 | 15.63–78.26 | 47.01 | 0.0667 | |
50 | 10.21 | 19.35–37.81 | 28.16 | 0.0399 |
42.36 | 17.53–31.48 | 23.61 | 0.0335 | |
76.28 | 12.67–24.59 | 18.83 | 0.0267 | |
100 | 10.21 | 8.26–19.17 | 14.56 | 0.0206 |
42.36 | 8.13–17.43 | 12.89 | 0.0183 | |
76.28 | 5.37–15.67 | 10.72 | 0.0152 | |
200 | 10.21 | 5.83–10.56 | 7.38 | 0.0105 |
42.36 | 4.23–10.38 | 6.01 | 0.0085 | |
76.28 | 3.41–9.26 | 5.68 | 0.0081 |
The average radiation dose rate at 25, 50, 100, and 200 cm from the patient’s chest level is shown in Table 2. The average radiation dose rate measured at 1 m distance from the patients’ chest level and 10.21 min after radiopharmaceutical injection was 16.27 μSv h−1 (range 7.83–24.71). Then, the average radiation dose rate decayed down to 13.65 μSv h−1(range 7.12–21.43) after 42.36 min, while the measured average radiation dose rate after 76.28 min was lower at 12.41 μSv h−1 (range 6.43–19.36) at 100 cm from patient’s chest level.
Radiation dose rates at patient’s chest level at different distances and at different times after injection
Distance from patient (cm) | Time after the injection (min) | Dose rate range (μSv h−1) | Mean dose rate (μSv h−1) | Normalized mean dose rate (μSv h−1 MBq−1) |
---|---|---|---|---|
25 | 10.21 | 61.83–172.29 | 124.33 | 0.1763 |
42.36 | 44.97–155.43 | 99.13 | 0.1406 | |
76.28 | 38.43–143.52 | 78.13 | 0.1108 | |
50 | 10.21 | 23.97–81.26 | 44.16 | 0.0626 |
42.36 | 22.63–54.78 | 38.38 | 0.0544 | |
76.28 | 21.34–48.53 | 33.44 | 0.0474 | |
100 | 10.21 | 7.83–24.71 | 16.27 | 0.0231 |
42.36 | 7.12–21.43 | 13.65 | 0.0194 | |
76.28 | 6.43–19.36 | 12.41 | 0.0176 | |
200 | 10.21 | 4.38–9.56 | 8.41 | 0.0119 |
42.36 | 4.13–9.12 | 6.43 | 0.0091 | |
76.28 | 4.01–9.07 | 6.36 | 0.0090 |
The average radiation dose rate measured at 1 m distance from the patients’ foot level and 10.21 min after radiopharmaceutical injection was 13.38 μSv h−1 (range 7.52–19.68). Then, the average radiation dose rate decayed down to 12.34 μSv h−1 (range 7.41–17.59) after 42.36 min, while the measured average radiation dose rate after 76.28 min was lower at 11.16 μSv h−1 (range 5.98–15.43) at 100 cm from patient’s foot level. The obtained results are tabulated in Table 3.
Radiation dose rates at patient’s foot level at different distances and at different times after injection
Distance from patient (cm) | Time after the injection (min) | Dose rate range (μSv h−1) | Mean dose rate (μSv h−1) | Normalized mean dose rate (μSv h−1 MBq−1) |
---|---|---|---|---|
25 | 10.21 | 26.89–92.51 | 46.94 | 0.0666 |
42.36 | 20.13–66.34 | 40.38 | 0.0573 | |
76.28 | 18.96–56.31 | 32.27 | 0.0458 | |
50 | 10.21 | 16.53–45.86 | 23.55 | 0.0334 |
42.36 | 14.56–30.08 | 21.05 | 0.0298 | |
76.28 | 7.89–26.52 | 18.66 | 0.0265 | |
100 | 10.21 | 7.52–19.68 | 13.38 | 0.0190 |
42.36 | 7.41–17.59 | 12.34 | 0.0175 | |
76.28 | 5.98–15.43 | 11.16 | 0.0158 | |
200 | 10.21 | 3.97–9.53 | 6.12 | 0.0087 |
42.36 | 3.72–9.32 | 5.78 | 0.0082 | |
76.28 | 3.04–7.53 | 5.27 | 0.0075 |
10.21 min after radiopharmaceutical injection to the patient, it was observed that the radiation dose rate decreased as the distance from the patient increased. Measurements at head, chest, and foot levels showed strong correlations between distance from the patient and radiation dose rate. Correlation coefficients were 0.995 for head level, 0.990 for chest level, and 0.996 for foot level (Figure 2).

10.21 min after injection, the patient’s head, chest, and foot radiation dose rates.
42.36 min after injection to the patient, radiation dose rate decreased as the distance from the patient increased. Measurements at head, chest, and foot levels showed strong correlations between distance from the patient and radiation dose rate. Correlation coefficients were 0.997 for head level, 0.996 for chest level, and 0.995 for foot level (Figure 3).

42.36 min after injection, the patient’s head, chest, and foot radiation dose rates.
76.28 min after injection to the patient, radiation dose rate decreased as the distance from the patient increased. Measurements at head, chest, and foot levels showed strong correlations between distance from the patient and radiation dose rate. Correlation coefficients were 0.988 for head level, 0.994 for chest level, and 0.992 for foot level (Figure 4).

76.28 min after injection, the patient’s head, chest, and foot radiation dose rates.
Radiation dose rate measurements at the patient’s head level were found to decrease with the increase in time. In the measurements at the head level, the correlation coefficients between radiation dose rate and time at 25, 50, 100, and 200 cm distances from the patient were 0.960, 0.996, 0.989, and 0.893, respectively (Figure 5).

Radiation dose rate at different distances from the patient’s head level.
Radiation dose rate measurements at the patient’s chest level were found to decrease with the increase in time. In the measurements at the chest level, the correlation coefficients between the radiation dose rate and time at 25, 50, 100, and 200 cm distances from the patient were 1, 0.999, 0.966, and 0.766, respectively (Figure 6).

Radiation dose rate at different distances from the patient’s chest level.
Radiation dose rate measurements at the patient’s foot level were found to decrease with the increase in time. In the measurements at the foot level, the correlation coefficients between radiation dose rate and time at 25, 50, 100, and 200 cm distances from the patient were 0.990, 1, 0.997, and 0.985, respectively (Figure 7). The radiation dose rate distribution 10.21, 42.36, and 76.28 min after radiopharmaceutical injection to the patient is shown in Figures 8–10.

Radiation dose rate at different distances from the patient’s foot level.

Radiation dose rate distribution at 10.21 min after injection.

Radiation dose rate distribution at 42.36 min after injection.

Radiation dose rate distribution at 76.28 min after injection.
Demir et al. found that in 2010, 87 min after the patient was injected with 550 MBq FDG, the radiation dose rate at a distance of 1 m from the patient was 74 μSv h−1 [10]. Cronin et al. found that in 1999, 120 min after the patient was injected with 323 MBq FDG, the radiation dose rate at a distance of 1 m from the patient was 14.7 μSv h−1 [11]. Zhang-Yin et al. found that in 2017, 95 min after the patient was injected with 176 MBq FDG, the radiation dose rate at a distance of 1 m from the patient was 9.34 μSv h−1 [12]. Gunay and Abamor found that in 2018, 77 min after the patient was injected with 300 MBq FDG, the radiation dose rate at a distance of 1 m from the patient was 15 μSv h−1 [13].
Günay et al. investigated the radiation dose rates at different distances from the patient after injecting Tc-99m in two different studies in 2019 [14,15]. One of these studies was performed on cardiac patients. In this study conducted by Günay et al., 276 MBq radiopharmaceuticals were injected to the patients. Radiation dose rate was measured at a distance of 1 m from patients. Radiation dose rates at 7.6, 36.5, and 66.4 min after injection were 9.07, 7.93, and 7.83 μSv h−1, respectively. In the other study, environmental radiation doses were determined in patients undergoing Tc-99m DMSA cortical renal scintigraphy. In this study conducted by Günay et al., 168 MBq radiopharmaceuticals were injected to the patients. Radiation dose rate was measured at a distance of 1 m from patients. The mean radiation dose at 5.07, 35.60, and 68.57 min after injection were found to be 5.06, 4.76, and 4.18 μSv h−1 at a distance of 1 m from the patients, respectively. Besides those of previous works, a number of radiation dose measurements and dosimetric studies have been performed for different purposes by different groups [16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38].
Since radiation containing different amounts of activity was injected into patients in different previous studies, depending on the type of disease, the dose rate emitted from the patient was found to be different in each study. The radiation dose rate results in this study were found to be higher than some previous similar studies and lower than others.
4 Conclusion
In this study, the radiation dose rate emitted to the environment after radiopharmaceutical injection was determined by patients undergoing bone scintigraphy imaging. Radiation dose rate measurements were made at different distances from the patient and at different levels of the patient. Measurements were made at different times to determine the relationship between radiation dose rate and time. A safe time and distance were determined for radiation workers and the public to approach patients who underwent bone scintigraphy.
Radiation worker should be exposed to less than 10 μSv h−1 dose [39]. Radiation workers should stay 1 m away from the patient for 130 min after radiopharmaceutical injection during bone scintigraphy imaging.
Radiation dose rate for the public should be less than 1 μSv h−1. According to the equation between the radiation dose rate of 1 m from the patient’s chest level and time, 130 min after radiopharmaceutical injection, the radiation dose rate of 1 m from the patient is less than 1 μSv h−1. Therefore, following bone scintigraphy applications, it is appropriate for the patient to restrain social activities such as being 1 m away from other people and using public transport, for at least 130 min after injection. In nuclear medicine, radiation of different activities is injected for different diseases. In future studies, it is recommended to measure the radiation dose rates emitted by patients injected with radiation of different activities.
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Funding information: The authors state no funding involved.
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Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Conflict of interest: The authors state no conflict of interest.
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Ethical approval: The research related to human use has been complied with all the relevant national regulations, institutional policies and in accordance with the tenets of the Helsinki Declaration, and has been approved by the authors’ institutional review board or equivalent committee.
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Articles in the same Issue
- Regular Articles
- Test influence of screen thickness on double-N six-light-screen sky screen target
- Analysis on the speed properties of the shock wave in light curtain
- Abundant accurate analytical and semi-analytical solutions of the positive Gardner–Kadomtsev–Petviashvili equation
- Measured distribution of cloud chamber tracks from radioactive decay: A new empirical approach to investigating the quantum measurement problem
- Nuclear radiation detection based on the convolutional neural network under public surveillance scenarios
- Effect of process parameters on density and mechanical behaviour of a selective laser melted 17-4PH stainless steel alloy
- Performance evaluation of self-mixing interferometer with the ceramic type piezoelectric accelerometers
- Effect of geometry error on the non-Newtonian flow in the ceramic microchannel molded by SLA
- Numerical investigation of ozone decomposition by self-excited oscillation cavitation jet
- Modeling electrostatic potential in FDSOI MOSFETS: An approach based on homotopy perturbations
- Modeling analysis of microenvironment of 3D cell mechanics based on machine vision
- Numerical solution for two-dimensional partial differential equations using SM’s method
- Multiple velocity composition in the standard synchronization
- Electroosmotic flow for Eyring fluid with Navier slip boundary condition under high zeta potential in a parallel microchannel
- Soliton solutions of Calogero–Degasperis–Fokas dynamical equation via modified mathematical methods
- Performance evaluation of a high-performance offshore cementing wastes accelerating agent
- Sapphire irradiation by phosphorus as an approach to improve its optical properties
- A physical model for calculating cementing quality based on the XGboost algorithm
- Experimental investigation and numerical analysis of stress concentration distribution at the typical slots for stiffeners
- An analytical model for solute transport from blood to tissue
- Finite-size effects in one-dimensional Bose–Einstein condensation of photons
- Drying kinetics of Pleurotus eryngii slices during hot air drying
- Computer-aided measurement technology for Cu2ZnSnS4 thin-film solar cell characteristics
- QCD phase diagram in a finite volume in the PNJL model
- Study on abundant analytical solutions of the new coupled Konno–Oono equation in the magnetic field
- Experimental analysis of a laser beam propagating in angular turbulence
- Numerical investigation of heat transfer in the nanofluids under the impact of length and radius of carbon nanotubes
- Multiple rogue wave solutions of a generalized (3+1)-dimensional variable-coefficient Kadomtsev--Petviashvili equation
- Optical properties and thermal stability of the H+-implanted Dy3+/Tm3+-codoped GeS2–Ga2S3–PbI2 chalcohalide glass waveguide
- Nonlinear dynamics for different nonautonomous wave structure solutions
- Numerical analysis of bioconvection-MHD flow of Williamson nanofluid with gyrotactic microbes and thermal radiation: New iterative method
- Modeling extreme value data with an upside down bathtub-shaped failure rate model
- Abundant optical soliton structures to the Fokas system arising in monomode optical fibers
- Analysis of the partially ionized kerosene oil-based ternary nanofluid flow over a convectively heated rotating surface
- Multiple-scale analysis of the parametric-driven sine-Gordon equation with phase shifts
- Magnetofluid unsteady electroosmotic flow of Jeffrey fluid at high zeta potential in parallel microchannels
- Effect of plasma-activated water on microbial quality and physicochemical properties of fresh beef
- The finite element modeling of the impacting process of hard particles on pump components
- Analysis of respiratory mechanics models with different kernels
- Extended warranty decision model of failure dependence wind turbine system based on cost-effectiveness analysis
- Breather wave and double-periodic soliton solutions for a (2+1)-dimensional generalized Hirota–Satsuma–Ito equation
- First-principle calculation of electronic structure and optical properties of (P, Ga, P–Ga) doped graphene
- Numerical simulation of nanofluid flow between two parallel disks using 3-stage Lobatto III-A formula
- Optimization method for detection a flying bullet
- Angle error control model of laser profilometer contact measurement
- Numerical study on flue gas–liquid flow with side-entering mixing
- Travelling waves solutions of the KP equation in weakly dispersive media
- Characterization of damage morphology of structural SiO2 film induced by nanosecond pulsed laser
- A study of generalized hypergeometric Matrix functions via two-parameter Mittag–Leffler matrix function
- Study of the length and influencing factors of air plasma ignition time
- Analysis of parametric effects in the wave profile of the variant Boussinesq equation through two analytical approaches
- The nonlinear vibration and dispersive wave systems with extended homoclinic breather wave solutions
- Generalized notion of integral inequalities of variables
- The seasonal variation in the polarization (Ex/Ey) of the characteristic wave in ionosphere plasma
- Impact of COVID 19 on the demand for an inventory model under preservation technology and advance payment facility
- Approximate solution of linear integral equations by Taylor ordering method: Applied mathematical approach
- Exploring the new optical solitons to the time-fractional integrable generalized (2+1)-dimensional nonlinear Schrödinger system via three different methods
- Irreversibility analysis in time-dependent Darcy–Forchheimer flow of viscous fluid with diffusion-thermo and thermo-diffusion effects
- Double diffusion in a combined cavity occupied by a nanofluid and heterogeneous porous media
- NTIM solution of the fractional order parabolic partial differential equations
- Jointly Rayleigh lifetime products in the presence of competing risks model
- Abundant exact solutions of higher-order dispersion variable coefficient KdV equation
- Laser cutting tobacco slice experiment: Effects of cutting power and cutting speed
- Performance evaluation of common-aperture visible and long-wave infrared imaging system based on a comprehensive resolution
- Diesel engine small-sample transfer learning fault diagnosis algorithm based on STFT time–frequency image and hyperparameter autonomous optimization deep convolutional network improved by PSO–GWO–BPNN surrogate model
- Analyses of electrokinetic energy conversion for periodic electromagnetohydrodynamic (EMHD) nanofluid through the rectangular microchannel under the Hall effects
- Propagation properties of cosh-Airy beams in an inhomogeneous medium with Gaussian PT-symmetric potentials
- Dynamics investigation on a Kadomtsev–Petviashvili equation with variable coefficients
- Study on fine characterization and reconstruction modeling of porous media based on spatially-resolved nuclear magnetic resonance technology
- Optimal block replacement policy for two-dimensional products considering imperfect maintenance with improved Salp swarm algorithm
- A hybrid forecasting model based on the group method of data handling and wavelet decomposition for monthly rivers streamflow data sets
- Hybrid pencil beam model based on photon characteristic line algorithm for lung radiotherapy in small fields
- Surface waves on a coated incompressible elastic half-space
- Radiation dose measurement on bone scintigraphy and planning clinical management
- Lie symmetry analysis for generalized short pulse equation
- Spectroscopic characteristics and dissociation of nitrogen trifluoride under external electric fields: Theoretical study
- Cross electromagnetic nanofluid flow examination with infinite shear rate viscosity and melting heat through Skan-Falkner wedge
- Convection heat–mass transfer of generalized Maxwell fluid with radiation effect, exponential heating, and chemical reaction using fractional Caputo–Fabrizio derivatives
- Weak nonlinear analysis of nanofluid convection with g-jitter using the Ginzburg--Landau model
- Strip waveguides in Yb3+-doped silicate glass formed by combination of He+ ion implantation and precise ultrashort pulse laser ablation
- Best selected forecasting models for COVID-19 pandemic
- Research on attenuation motion test at oblique incidence based on double-N six-light-screen system
- Review Articles
- Progress in epitaxial growth of stanene
- Review and validation of photovoltaic solar simulation tools/software based on case study
- Brief Report
- The Debye–Scherrer technique – rapid detection for applications
- Rapid Communication
- Radial oscillations of an electron in a Coulomb attracting field
- Special Issue on Novel Numerical and Analytical Techniques for Fractional Nonlinear Schrodinger Type - Part II
- The exact solutions of the stochastic fractional-space Allen–Cahn equation
- Propagation of some new traveling wave patterns of the double dispersive equation
- A new modified technique to study the dynamics of fractional hyperbolic-telegraph equations
- An orthotropic thermo-viscoelastic infinite medium with a cylindrical cavity of temperature dependent properties via MGT thermoelasticity
- Modeling of hepatitis B epidemic model with fractional operator
- Special Issue on Transport phenomena and thermal analysis in micro/nano-scale structure surfaces - Part III
- Investigation of effective thermal conductivity of SiC foam ceramics with various pore densities
- Nonlocal magneto-thermoelastic infinite half-space due to a periodically varying heat flow under Caputo–Fabrizio fractional derivative heat equation
- The flow and heat transfer characteristics of DPF porous media with different structures based on LBM
- Homotopy analysis method with application to thin-film flow of couple stress fluid through a vertical cylinder
- Special Issue on Advanced Topics on the Modelling and Assessment of Complicated Physical Phenomena - Part II
- Asymptotic analysis of hepatitis B epidemic model using Caputo Fabrizio fractional operator
- Influence of chemical reaction on MHD Newtonian fluid flow on vertical plate in porous medium in conjunction with thermal radiation
- Structure of analytical ion-acoustic solitary wave solutions for the dynamical system of nonlinear wave propagation
- Evaluation of ESBL resistance dynamics in Escherichia coli isolates by mathematical modeling
- On theoretical analysis of nonlinear fractional order partial Benney equations under nonsingular kernel
- The solutions of nonlinear fractional partial differential equations by using a novel technique
- Modelling and graphing the Wi-Fi wave field using the shape function
- Generalized invexity and duality in multiobjective variational problems involving non-singular fractional derivative
- Impact of the convergent geometric profile on boundary layer separation in the supersonic over-expanded nozzle
- Variable stepsize construction of a two-step optimized hybrid block method with relative stability
- Thermal transport with nanoparticles of fractional Oldroyd-B fluid under the effects of magnetic field, radiations, and viscous dissipation: Entropy generation; via finite difference method
- Special Issue on Advanced Energy Materials - Part I
- Voltage regulation and power-saving method of asynchronous motor based on fuzzy control theory
- The structure design of mobile charging piles
- Analysis and modeling of pitaya slices in a heat pump drying system
- Design of pulse laser high-precision ranging algorithm under low signal-to-noise ratio
- Special Issue on Geological Modeling and Geospatial Data Analysis
- Determination of luminescent characteristics of organometallic complex in land and coal mining
- InSAR terrain mapping error sources based on satellite interferometry
Articles in the same Issue
- Regular Articles
- Test influence of screen thickness on double-N six-light-screen sky screen target
- Analysis on the speed properties of the shock wave in light curtain
- Abundant accurate analytical and semi-analytical solutions of the positive Gardner–Kadomtsev–Petviashvili equation
- Measured distribution of cloud chamber tracks from radioactive decay: A new empirical approach to investigating the quantum measurement problem
- Nuclear radiation detection based on the convolutional neural network under public surveillance scenarios
- Effect of process parameters on density and mechanical behaviour of a selective laser melted 17-4PH stainless steel alloy
- Performance evaluation of self-mixing interferometer with the ceramic type piezoelectric accelerometers
- Effect of geometry error on the non-Newtonian flow in the ceramic microchannel molded by SLA
- Numerical investigation of ozone decomposition by self-excited oscillation cavitation jet
- Modeling electrostatic potential in FDSOI MOSFETS: An approach based on homotopy perturbations
- Modeling analysis of microenvironment of 3D cell mechanics based on machine vision
- Numerical solution for two-dimensional partial differential equations using SM’s method
- Multiple velocity composition in the standard synchronization
- Electroosmotic flow for Eyring fluid with Navier slip boundary condition under high zeta potential in a parallel microchannel
- Soliton solutions of Calogero–Degasperis–Fokas dynamical equation via modified mathematical methods
- Performance evaluation of a high-performance offshore cementing wastes accelerating agent
- Sapphire irradiation by phosphorus as an approach to improve its optical properties
- A physical model for calculating cementing quality based on the XGboost algorithm
- Experimental investigation and numerical analysis of stress concentration distribution at the typical slots for stiffeners
- An analytical model for solute transport from blood to tissue
- Finite-size effects in one-dimensional Bose–Einstein condensation of photons
- Drying kinetics of Pleurotus eryngii slices during hot air drying
- Computer-aided measurement technology for Cu2ZnSnS4 thin-film solar cell characteristics
- QCD phase diagram in a finite volume in the PNJL model
- Study on abundant analytical solutions of the new coupled Konno–Oono equation in the magnetic field
- Experimental analysis of a laser beam propagating in angular turbulence
- Numerical investigation of heat transfer in the nanofluids under the impact of length and radius of carbon nanotubes
- Multiple rogue wave solutions of a generalized (3+1)-dimensional variable-coefficient Kadomtsev--Petviashvili equation
- Optical properties and thermal stability of the H+-implanted Dy3+/Tm3+-codoped GeS2–Ga2S3–PbI2 chalcohalide glass waveguide
- Nonlinear dynamics for different nonautonomous wave structure solutions
- Numerical analysis of bioconvection-MHD flow of Williamson nanofluid with gyrotactic microbes and thermal radiation: New iterative method
- Modeling extreme value data with an upside down bathtub-shaped failure rate model
- Abundant optical soliton structures to the Fokas system arising in monomode optical fibers
- Analysis of the partially ionized kerosene oil-based ternary nanofluid flow over a convectively heated rotating surface
- Multiple-scale analysis of the parametric-driven sine-Gordon equation with phase shifts
- Magnetofluid unsteady electroosmotic flow of Jeffrey fluid at high zeta potential in parallel microchannels
- Effect of plasma-activated water on microbial quality and physicochemical properties of fresh beef
- The finite element modeling of the impacting process of hard particles on pump components
- Analysis of respiratory mechanics models with different kernels
- Extended warranty decision model of failure dependence wind turbine system based on cost-effectiveness analysis
- Breather wave and double-periodic soliton solutions for a (2+1)-dimensional generalized Hirota–Satsuma–Ito equation
- First-principle calculation of electronic structure and optical properties of (P, Ga, P–Ga) doped graphene
- Numerical simulation of nanofluid flow between two parallel disks using 3-stage Lobatto III-A formula
- Optimization method for detection a flying bullet
- Angle error control model of laser profilometer contact measurement
- Numerical study on flue gas–liquid flow with side-entering mixing
- Travelling waves solutions of the KP equation in weakly dispersive media
- Characterization of damage morphology of structural SiO2 film induced by nanosecond pulsed laser
- A study of generalized hypergeometric Matrix functions via two-parameter Mittag–Leffler matrix function
- Study of the length and influencing factors of air plasma ignition time
- Analysis of parametric effects in the wave profile of the variant Boussinesq equation through two analytical approaches
- The nonlinear vibration and dispersive wave systems with extended homoclinic breather wave solutions
- Generalized notion of integral inequalities of variables
- The seasonal variation in the polarization (Ex/Ey) of the characteristic wave in ionosphere plasma
- Impact of COVID 19 on the demand for an inventory model under preservation technology and advance payment facility
- Approximate solution of linear integral equations by Taylor ordering method: Applied mathematical approach
- Exploring the new optical solitons to the time-fractional integrable generalized (2+1)-dimensional nonlinear Schrödinger system via three different methods
- Irreversibility analysis in time-dependent Darcy–Forchheimer flow of viscous fluid with diffusion-thermo and thermo-diffusion effects
- Double diffusion in a combined cavity occupied by a nanofluid and heterogeneous porous media
- NTIM solution of the fractional order parabolic partial differential equations
- Jointly Rayleigh lifetime products in the presence of competing risks model
- Abundant exact solutions of higher-order dispersion variable coefficient KdV equation
- Laser cutting tobacco slice experiment: Effects of cutting power and cutting speed
- Performance evaluation of common-aperture visible and long-wave infrared imaging system based on a comprehensive resolution
- Diesel engine small-sample transfer learning fault diagnosis algorithm based on STFT time–frequency image and hyperparameter autonomous optimization deep convolutional network improved by PSO–GWO–BPNN surrogate model
- Analyses of electrokinetic energy conversion for periodic electromagnetohydrodynamic (EMHD) nanofluid through the rectangular microchannel under the Hall effects
- Propagation properties of cosh-Airy beams in an inhomogeneous medium with Gaussian PT-symmetric potentials
- Dynamics investigation on a Kadomtsev–Petviashvili equation with variable coefficients
- Study on fine characterization and reconstruction modeling of porous media based on spatially-resolved nuclear magnetic resonance technology
- Optimal block replacement policy for two-dimensional products considering imperfect maintenance with improved Salp swarm algorithm
- A hybrid forecasting model based on the group method of data handling and wavelet decomposition for monthly rivers streamflow data sets
- Hybrid pencil beam model based on photon characteristic line algorithm for lung radiotherapy in small fields
- Surface waves on a coated incompressible elastic half-space
- Radiation dose measurement on bone scintigraphy and planning clinical management
- Lie symmetry analysis for generalized short pulse equation
- Spectroscopic characteristics and dissociation of nitrogen trifluoride under external electric fields: Theoretical study
- Cross electromagnetic nanofluid flow examination with infinite shear rate viscosity and melting heat through Skan-Falkner wedge
- Convection heat–mass transfer of generalized Maxwell fluid with radiation effect, exponential heating, and chemical reaction using fractional Caputo–Fabrizio derivatives
- Weak nonlinear analysis of nanofluid convection with g-jitter using the Ginzburg--Landau model
- Strip waveguides in Yb3+-doped silicate glass formed by combination of He+ ion implantation and precise ultrashort pulse laser ablation
- Best selected forecasting models for COVID-19 pandemic
- Research on attenuation motion test at oblique incidence based on double-N six-light-screen system
- Review Articles
- Progress in epitaxial growth of stanene
- Review and validation of photovoltaic solar simulation tools/software based on case study
- Brief Report
- The Debye–Scherrer technique – rapid detection for applications
- Rapid Communication
- Radial oscillations of an electron in a Coulomb attracting field
- Special Issue on Novel Numerical and Analytical Techniques for Fractional Nonlinear Schrodinger Type - Part II
- The exact solutions of the stochastic fractional-space Allen–Cahn equation
- Propagation of some new traveling wave patterns of the double dispersive equation
- A new modified technique to study the dynamics of fractional hyperbolic-telegraph equations
- An orthotropic thermo-viscoelastic infinite medium with a cylindrical cavity of temperature dependent properties via MGT thermoelasticity
- Modeling of hepatitis B epidemic model with fractional operator
- Special Issue on Transport phenomena and thermal analysis in micro/nano-scale structure surfaces - Part III
- Investigation of effective thermal conductivity of SiC foam ceramics with various pore densities
- Nonlocal magneto-thermoelastic infinite half-space due to a periodically varying heat flow under Caputo–Fabrizio fractional derivative heat equation
- The flow and heat transfer characteristics of DPF porous media with different structures based on LBM
- Homotopy analysis method with application to thin-film flow of couple stress fluid through a vertical cylinder
- Special Issue on Advanced Topics on the Modelling and Assessment of Complicated Physical Phenomena - Part II
- Asymptotic analysis of hepatitis B epidemic model using Caputo Fabrizio fractional operator
- Influence of chemical reaction on MHD Newtonian fluid flow on vertical plate in porous medium in conjunction with thermal radiation
- Structure of analytical ion-acoustic solitary wave solutions for the dynamical system of nonlinear wave propagation
- Evaluation of ESBL resistance dynamics in Escherichia coli isolates by mathematical modeling
- On theoretical analysis of nonlinear fractional order partial Benney equations under nonsingular kernel
- The solutions of nonlinear fractional partial differential equations by using a novel technique
- Modelling and graphing the Wi-Fi wave field using the shape function
- Generalized invexity and duality in multiobjective variational problems involving non-singular fractional derivative
- Impact of the convergent geometric profile on boundary layer separation in the supersonic over-expanded nozzle
- Variable stepsize construction of a two-step optimized hybrid block method with relative stability
- Thermal transport with nanoparticles of fractional Oldroyd-B fluid under the effects of magnetic field, radiations, and viscous dissipation: Entropy generation; via finite difference method
- Special Issue on Advanced Energy Materials - Part I
- Voltage regulation and power-saving method of asynchronous motor based on fuzzy control theory
- The structure design of mobile charging piles
- Analysis and modeling of pitaya slices in a heat pump drying system
- Design of pulse laser high-precision ranging algorithm under low signal-to-noise ratio
- Special Issue on Geological Modeling and Geospatial Data Analysis
- Determination of luminescent characteristics of organometallic complex in land and coal mining
- InSAR terrain mapping error sources based on satellite interferometry