• Title/Summary/Keyword: low radiation

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Comparison of Perception Differences About Nuclear Energy in 4 East Asian Country Students: Aiming at $10^{th}$ Grade Students who Participated in Scientific Camps, from Four East Asian Countries: Korea, Japan, Taiwan, and Singapore (동아시아 4개국 학생들의 핵에너지에 대한 인식 비교: 과학캠프에 참가한 한국, 일본, 대만, 싱가포르 10학년 학생들을 대상으로)

  • Lee, Hyeong-Jae;Park, Sang-Tae
    • Journal of The Korean Association For Science Education
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    • v.32 no.4
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    • pp.775-788
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    • 2012
  • This study was done at a scientific camp sponsored by Nara Women's University Secondary School, Japan. In this school, $10^{th}$ grade students from 4 East Asian countries: Korea, Japan, Taiwan, and Singapore, participated. We made a research on students' perceptions about nuclear energy. Sample populations include 77 students in total, with 12 Korean, 46 Japanese, 9 Taiwanese and 10 Singaporean students. Overall perceptions comparison about nuclear energy shows average values from the order of highest Korea, Taiwan, Singapore, and to lowest, Japan. We implemented a T-test to identify perception differences about nuclear energy, with one group that include 3 countries (Korea, Taiwan and Singapore) and another group that includes all the Japanese students. T-test results of perceptions about nuclear energy shows students from the 3 countries of Korea, Taiwan and Singapore having higher average than Japanese students. (p<.05). Korean average scores regarding overall perceptions about nuclear energy show as the highest in all 4 East Asian countries and also highest in all subcategories. On the contrary in Japan, they have lower and negative perceptions of nuclear energy. In spite of these facts, perceptions of Japanese students about nuclear energy seem lowest and negative mainly because of the recent Fukushima nuclear power plant disaster, caused by the tsunami and its subsequent damages and fears of radiation leaks, etc. This shows that negative information about future disasters and its resulting damages like the Chernobyl nuclear accident could influence more on people's risk perception than general information like nuclear energy-related technologies or the news that the plant is operating normally, etc. Even if the possibility of this kind of accident is very low, just one accident could bring abnormal risks to technology itself. This strong signal makes negative image and strengthens its perceptions to the people. This could bring a stigma about nuclear energy. This study shows that Government's policy about the highest priority for nuclear energy safety is most important. As long as such perception and decision are fixed, we found that it might not be easy to get changed again because they were already fortified and maintained.

Preoperative Evaluation of Brain Lesion with $^{201}Tl$ Brain SPECT: Is It Useful to Differentiate Benign and Malignant Lesions? (수술 전 뇌 병변의 $^{201}Tl$ 뇌 SPECT: 양성과 악성 병변을 감별하는데 유용한가?)

  • Sohn, Hyung-Sun;Kim, Euy-Neyng;Kim, Sung-Hoon;Chung, Yong-An;Chung, Soo-Kyo;Bong, Yong-Gil;Lee, Youn-Soo
    • The Korean Journal of Nuclear Medicine
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    • v.34 no.5
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    • pp.371-380
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    • 2000
  • Purpose: Thallim-201 ($^{201}Tl$) brain SPECT, which can represent cellular activity of brain lesions, may provide more useful information in differentiating between benign and malignant brain lesions more so than CT of MRI, that merely represents anatomic changes or breakdown of blood brain barrier. We used $^{201}Tl$ brain SPECT prospectively to evaluate the utility of $^{201}Tl$-indices as an indicator of benign or malig nant lesions. Materials and Methods: We studied 28 patients. There were 13 cases of benign lesions (3: nonspecific benign lesion, 3: meningioma, 2: low grade glioma, 1: tuberculoma, central neurocytoma, hemangioblastoma, radiation necrosis, and choroid plexus papilloma) and 15 cases of malignant lesions (6: glioblastoma multiforme, 5: anaplastic glioma, 2: medulloblastoma, 1: metastasis and lymphoma). In all patients, CT and/or MRI were obtained and then $^{201}Tl$ brain SPECT was obtained with measuring mean $^{201}Tl$ index and peak $^{201}Tl$ index. An unpaired t-test was performed to compare the $^{201}Tl$-indices and pathologic diagnoses to evaluate the utility of $^{201}Tl$-indices as all indicator of benign or malignant lesions. Results: There were no statistically significant difference in $^{201}Tl$-indices between benign and malignant brain lesion (p>0.05). Conclusion: These results demonstrated that we could not use $^{201}Tl$ indices on brain SPECT alone as an indicator of benign or malignant brain lesions.

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The Contribution of Innovation Activity to the Output Growth of Emerging Economies: The Case of Kazakhstan

  • Smagulova, Sholpan;Mukasheva, Saltanat
    • Journal of Distribution Science
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    • v.10 no.7
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    • pp.33-41
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    • 2012
  • The purpose of this study is to analyse the state of the energy industry and to determine the efficiency of its functioning on the basis of energy conservation principle and application of innovative technologies aimed at improving the ecological modernisation of agricultural sectors of Kazakhstan. The research methodology is based on an integrated approach of financial and economic evaluation of the effectiveness of the investment project, based on calculation of elasticity, total costs and profitability, as well as on comparative, graphical and system analysis. The current stage is characterised by widely spread restructuring processes of electric power industry in many countries through introduction of new technical installations of energy facilities and increased government regulation in order to enhance the competitive advantage of electricity market. Electric power industry features a considerable value of creating areas. For example, by providing scientific and technical progress, it crucially affects not only the development but also the territorial organisation of productive forces, first of all the industry. In modern life, more than 90% of electricity and heat is obtained by Kazakhstan's economy by consuming non-renewable energy resources: different types of coal, oil shale, oil, natural gas and peat. Therefore, it is significant to ensure energy security, as the country faces a rapid fall back to mono-gas structure of fuel and energy balance. However, energy resources in Kazakhstan are spread very unevenly. Its main supplies are concentrated in northern and central parts of the republic, and the majority of consumers of electrical power live in the southern and western areas of the country. However, energy plays an important role in the economy of industrial production and to a large extent determines the level of competitive advantage, which is a promising condition for implementation of energy-saving and environmentally friendly technologies. In these circumstances, issues of modernisation and reforms of this sector in Kazakhstan gain more and more importance, which can be seen in the example of economically sustainable solutions of a large local monopoly company, significant savings in capital investment and efficiency of implementation of an investment project. A major disadvantage of development of electricity distribution companies is the prevalence of very high moral and physical amortisation of equipment, reaching almost 70-80%, which significantly increases the operating costs. For example, while an investment of 12 billion tenge was planned in 2009 in this branch, in 2012 it is planned to invest more than 17 billion. Obviously, despite the absolute increase, the rate of investment is still quite low, as the total demand in this area is at least more than 250 billion tenge. In addition, industrial infrastructure, including the objects of Kazakhstan electric power industry, have a tangible adverse impact on the environment. Thus, since there is a large number of various power projects that are sources of electromagnetic radiation, the environment is deteriorated. Hence, there is a need to optimise the efficiency of the organisation and management of production activities of energy companies, to create and implement new technologies, to ensure safe production and provide solutions to various environmental aspects. These are key strategic factors to ensure success of the modern energy sector of Kazakhstan. The contribution of authors in developing the scope of this subject is explained by the fact that there was not enough research in the energy sector, especially in the view of ecological modernisation. This work differs from similar works in Kazakhstan in the way that the proposed method of investment project calculation takes into account the time factor, which compares the current and future value of profit from the implementation of innovative equipment that helps to bring it to actual practise. The feasibility of writing this article lies in the need of forming a public policy in the industrial sector, including optimising the structure of energy disbursing rate, which complies with the terms of future modernised development of the domestic energy sector.

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Long-Term Observation of Temperature in the Coastal Waters Adjacent to the Wolsung Nuclear Power Plant (월성 원자력 발전소 주변 해역의 장기간 수온관측)

  • Chung, Jong-Yul;Kang, Hyoun-Woo;Shin, Young-Jae;Kim, Kye-Young;Jun, Ho-Kyung
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.3 no.4
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    • pp.183-192
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    • 1998
  • The long-term observation of temperature in the coastal waters adjacent to the Wolsung Nuclear Power Plant has been carried out from November 10, 1996 to August 22, 1997, for approximately 280 days using a real-time temperature measurement buoy system. The sea-surface temperature was measured at every 10 minute using 10 buoys. The vertical structure of temperature was investigated near the outlet of the plant with two thermistor chains equipped with 10 sensors at 1 m interval The monthly averaged temperature was the lowest with spatial average of $12.8^{\circ}C$ in February and was the highest in August with spatial average of $19.6^{\circ}C$. The extremely low temperature was frequently observed between June and August, which seems to be the consequence of the intrusion of cold water near the southeastern coast of Korea. Distributions of the daily and hourly averaged temperature show that the highest temperature always occurred near the outlet of the plant and the warm-water patch moved along the north-south direction with the semidiurnal period. The semidiurnal fluctuation of temperature was also observed near the surface of the vertical profiles. The spectral analysis of temperature between February and April 1997 shows that the semidiurnal components prevailed near the outlet. It is likely that the semidiurnal components were due to the prevailing semidiurnal tide in this region. In August 1997, the diurnal components were dominant at the surface water of all stations except Station 12, which suggests that the warm water from the outlet of the plant has less effects in summer on the surrounding waters than the strong solar radiation.

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A Computer Simulation for Small Animal Iodine-125 SPECT Development (소동물 Iodine-125 SPECT 개발을 위한 컴퓨터 시뮬레이션)

  • Jung, Jin-Ho;Choi, Yong;Chung, Yong-Hyun;Song, Tae-Yong;Jeong, Myung-Hwan;Hong, Key-Jo;Min, Byung-Jun;Choe, Yearn-Seong;Lee, Kyung-Han;Kim, Byung-Tae
    • The Korean Journal of Nuclear Medicine
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    • v.38 no.1
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    • pp.74-84
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    • 2004
  • Purpose: Since I-125 emits low energy (27-35 keV) radiation, thinner crystal and collimator could be employed and, hence, it is favorable to obtain high quality images. The purpose of this study was to derive the optimized parameters of I-125 SPECT using a new simulation tool, GATE (Geant4 Application for Tomographic Emission). Materials and Methods: To validate the simulation method, gamma camera developed by Weisenberger et al. was modeled. Nal(T1) plate crystal was used and its thickness was determined by calculating detection efficiency. Spatial resolution and sensitivity curves were estimated by changing variable parameters for parallel-hole and pinhole collimator. Peformances of I-125 SPECT equipped with the optimal collimator were also estimated. Results: in the validation study, simulations were found to agree well with experimental measurements in spatial resolution (4%) and sensitivity (3%). In order to acquire 98% gamma ray detection efficiency, Nal(T1) thickness was determined to be 1 mm. Hole diameter (mm), length (mm) and shape were chosen to be 0.2:5:square and 0.5:10:hexagonal for high resolution (HR) and general purpose (GP) parallel-hole collimator, respectively. Hole diameter, channel height and acceptance angle of pinhole (PH) collimator were determined to be 0.25 mm, 0.1 mm and 90 degree. The spatial resolutions of reconstructed image of the I-125 SPECT employing HR:GP:PH were 1.2:1.7:0.8 mm. The sensitivities of HR:GP:PH were 39.7:71.9:5.5 cps/MBq. Conclusion: The optimal crystal and collimator parameters for I-125 Imaging were derived by simulation using GATE. The results indicate that excellent resolution and sensitivity imaging is feasible using I-125 SPECT.

A Study of Injection Dose for Patients and Exposure Dose for Technologists from the PET/CT Systems (PET/CT 장비 특성에 따른 방사성 의약품 주입량이 방사선 종사자에게 미치는 영향)

  • Park, Hoon-Hee;Oh, Ki-Beak;Lee, Seung-Jae;Bhan, Young-Kag;Kang, Chun-Goo;Lim, Han-Sang;Kim, Jae-Sam;Lee, Chang-Ho
    • The Korean Journal of Nuclear Medicine Technology
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    • v.15 no.1
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    • pp.45-50
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    • 2011
  • Purpose: It appears the different value when the injection dose is calculating for patients on each PET/CT systems. It directly affects the technologists' radiation exposed dose. We studied the effect of the variable injection doses from several PET/CT systems to exposure dose for technologists. Materials and Methods: Six technologists have worked for 5 months through unit rotations with 3 PET/CT systems {Scanner 1 (S1): 0.15 mCi/kg, Scanner 2 (S2): 0.17 mCi/kg, Scanner 3 (S3): 0.12 mCi/kg}. Eighteen to 19 patients have had examinations per a day on each PET/CT systems. Examination parameters were adjusted to the same. TLDs were used for checking the exposure dose of technologists. Results: Each technologists' the monthly average exposure dose was as follows; S1: 0.76 mSv, S2: 0.93 mSv, S3: 0.47 mSv. The maximum exposure dose was 1.12 mSv, and minimum was 0.42 mSv. The results showed significance in the correlation between the PET/CT system and the exposure dose (p<0.005). Conclusion: When the amount of injection dose was small, the exposure dose was decreased not only the patients but also the technologists. The exposure dose was decreased by the individual proficiency of technologists. However, the low injection dose can highly reduce the exposure dose for technologist so that there will be needed to following studies.

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The Evaluation of Usefulness of Pixelated Breast-Specific Gamma Imaging in Thyroid scan (Pixelated Breast-Specific Gamma Imaging(BSGI) 감마 카메라를 이용한 갑상선 검사의 유용성 평가)

  • Jung, Eun-Mi;Seong, Ji-Hye;Yoo, Hee-Jae
    • The Korean Journal of Nuclear Medicine Technology
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    • v.15 no.1
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    • pp.90-93
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    • 2011
  • Purpose: A Pixelated BSGI gamma camera has features to enhance resolution and sensitivity and minimize the distance between detector and organs by narrow FOV. Therefore, it is known as useful device to examine small organs such as thyroid, parathyroid and gall bladder. In general, when we would like to enlarge the size of images and obtain high resolution images by gamma camera in nuclear medicine study, we use pinhole collimator. The purpose of this study is to evaluate the usefulness of Pixelated BSGI gamma camera and to compare to it using pinhole collimator in thyroid scan which is a study of typical small organs. Materials and methods: (1) The evaluation of sensitivity and spatial resolution: We measured sensitivity and spatial resolution of Pixelated BSGI with LEHR collimator and Infinia gamma camera with pinhole collimator. The sensitivity was measured by point source sensitivity test recommended by IAEA. We acquired images considering dead time in BSGI gamma camera for 100 seconds and used $^{99m}TcO4-\;400{\mu}Ci$ line source. (2) The evaluation of thyroid phantom: The thyroid phantom was filled with $^{99m}TcO4-$. After set 300 sec or 100 kcts stop conditions, we acquired images from both pixelated BSGI gamma camera and Infinia gamma camera with LEHR collimator. And we performed all thyroid studies in the same way as current AMC's procedure. Results: (1) the result of sensitivity: As a result, the sensitivity and spatial resolution of pixelated BSGI gamma camera were better than Infinia's. The sensitivities of pixelated BSGI and Infinia gamma camera were $290cps/{\mu}Ci$ and $350cps/{\mu}Ci$ respectively. So, the sensitivity of pixelated BSGI was 1.2 times higher than Infinia's (2) the result of thyroid phantom: Consequently, we confirmed that images of Pixelated BSGI gamma camera were more distinguishable between hot and cold spot compared with Infinia gamma camera. Conclusion: A pixelated BSGI gamma camera is able to shorten the acquisition time. Furthermore, the patients are exposed to radiation less than before by reducing amount of radiopharmaceutical doses. Shortening scan time makes images better by minimizing patient's breath and motion. And also, the distance between organ and detector is minimized because detector of pixelated BSGI gamma camera is small and possible to rotate. When patient cannot move at all, it is useful since device is feasible to move itself. However, although a pixelated BSGI gamma camera has these advantages, the effect of dead time occurs over 2000 cts/s since it was produced only for breast scan. So, there were low concentrations in organ. Therefore, we should consider that it needs to take tests to adjust acquisition time and amount of radiopharmaceutical doses in thyroid scan case with a pixelated BSGI gamma camera.

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Sensitivity of Simulated Water Temperature to Vertical Mixing Scheme and Water Turbidity in the Yellow Sea (수직 혼합 모수화 기법과 탁도에 따른 황해 수온 민감도 실험)

  • Kwak, Myeong-Taek;Seo, Gwang-Ho;Choi, Byoung-Ju;Kim, Chang-Sin;Cho, Yang-Ki
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.18 no.3
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    • pp.111-121
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    • 2013
  • Accurate prediction of sea water temperature has been emphasized to make precise local weather forecast and to understand change of ecosystem. The Yellow Sea, which has turbid water and strong tidal current, is an unique shallow marginal sea. It is essential to include the effects of the turbidity and the strong tidal mixing for the realistic simulation of temperature distribution in the Yellow Sea. Evaluation of ocean circulation model response to vertical mixing scheme and turbidity is primary objective of this study. Three-dimensional ocean circulation model(Regional Ocean Modeling System) was used to perform numerical simulations. Mellor- Yamada level 2.5 closure (M-Y) and K-Profile Parameterization (KPP) scheme were selected for vertical mixing parameterization in this study. Effect of Jerlov water type 1, 3 and 5 was also evaluated. The simulated temperature distribution was compared with the observed data by National Fisheries Research and Development Institute to estimate model's response to turbidity and vertical mixing schemes in the Yellow Sea. Simulations with M-Y vertical mixing scheme produced relatively stronger vertical mixing and warmer bottom temperature than the observation. KPP scheme produced weaker vertical mixing and did not well reproduce tidal mixing front along the coast. However, KPP scheme keeps bottom temperature closer to the observation. Consequently, numerical ocean circulation simulations with M-Y vertical mixing scheme tends to produce well mixed vertical temperature structure and that with KPP vertical mixing scheme tends to make stratified vertical temperature structure. When Jerlov water type is higher, sea surface temperature is high and sea bottom temperature is low because downward shortwave radiation is almost absorbed near the sea surface.

Needs and Satisfaction of Cancer Patients on the Medical Services in Jeju Special Self-Governing Province (제주지역 암환자의 의료서비스 요구도 및 만족도 분석)

  • Kim, Woo-Jeong;Kim, Min-Young;Chang, Weon-Young;Choi, Jae-Hyuck
    • Journal of Hospice and Palliative Care
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    • v.13 no.3
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    • pp.153-160
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    • 2010
  • Purpose: The purpose of the present study was to investigate needs and satisfaction on the medical services of cancer patients in Jeju Special Self-Governing Province. Methods: Total 174 cancer patients, who visited at the clinic of Jeju National University Hospital, submitted informed consent and participated in this study from July 13 to July 30, 2009. Self questionnaire was used and data were analyzed with Kolmogorov-Smirnov test, Mann-Whitney U test, ANOVA, and Kruskal-Wallis test. Results: Participants expressed the needs of most economical support (3.38 out of 4), followed by counseling of treatment plan (3.22), information of disease (3.07), and disease management except cancer (2.97). Participants were satisfied most with religious counseling (3.41), followed by nursing service support (3.39), employment counseling (3.26), and counseling for family or interpersonal relationships (3.26). The satisfaction of economical support was the lowest (1.98). Satisfaction of men was higher than women, and needs in patients who were living with children was the highest. Patients who were living alone or with children showed the lowest satisfaction about the medical services. There were no significant differences in the general characteristics, however, participants who were older than 60 years of age or had higher income showed lower needs and higher satisfaction. There were no significant differences in the medical characteristics, however, thyroid cancer patients and patients who were treated with radiation therapy or transarterial embolization showed low satisfaction. Conclusion: Cancer patients seemed to need more economical support, information of treatment or disease, and symptom management. Furthermore, there were various needs about the services, depending on family formation or economical support of patients. Therefore, it is certain that patients who were suffering from other cancers, except the 5 major cancers, needed more services. In conclusion, continuous and systemic policy to consider patient's characteristics and needs are needed in community as well as health care system.

Distribution and Behavior of $^{137}Cs$ According to topography and nature of the soil around Yeong-Gwang NPPs, (영광원자력발전소 주변의 지형 및 지질에 따른 $^{137}Cs$ 분포 및 거동에 관한 연구)

  • Han Sang-Jun;Lee Goung-Jin;Kim Hee-Geun
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.2 no.4
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    • pp.271-278
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    • 2004
  • This paper shows our experiment is performed to understand the exposure tendency of $^{137}Cs$ according to the height of area and also, to supplement it by considering chemical characters of $^{137}Cs$ exposed to the soil. The samples we use for this experiment are from the general flat area of Yeonggwang county where it has NPPs, the high places of Keumjung & Bulgap mountains, and Naejan mountain where it is quite far from the NPPs. The data from this experiment show that the exposure of $^{137}Cs$ is not harmful since its range is around 252 Bq/kg-dry in most of sampled soils such as from the general flat area, the high place of Keumjung mountain where is 2 km away from the NPPs, the other high place of Bulgap mountain where is about 20 km away from the NPPs, and Naejan mountain where it is far from the NPPs. Not like the general flat area, however, the data show that the higher the area is the more $^{137}Cs$ is exposed. That is, at the top of mountains, the more $^{137}Cs$ is exposed compared to at the bottom area. It is almost $2{\~}6$ times more than the general flat area of Yeonggwang county where it has NPPs. The data also show that the spread of $^{137}Cs$ is deeply related to the geographical(the height of area, rainfall, etc..) factors and chemical factors of soils. As the geographical factors, there are far more chances to be exposed of $^{137}Cs$ at the high area of mountains through the air compared to at lower area and therefore, we can get more high-leveled readings of $^{137}Cs$ at the high area while it is low-leveled ones at the general flat area even if both of them have the same soil conditions. Regarding the chemical factors of soil, it is clarified that the CEC is the key factor. The CEC means the capability of sticking $^{137}Cs$ accumulated into the soil. Hence, the more CEC it has the more high-leveled readings of $^{137}Cs$ we get under the same geographical condition.

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