• Nuclear Engineering and Technology
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• 제54권11호
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• pp.4005-4012
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• 2022

As high-level radioactive waste (HLW) generated from nuclear power plants is harmful to the human body, it must be safely disposed of by an engineered barrier system consisting of disposal canisters and buffer and backfill materials. A gap exists between the canister and buffer material in a HLW repository and between the buffer material and natural rock-this gap may reduce the water-blocking ability and heat transfer efficiency of the engineered barrier materials. Herein, the basic characteristics and thermal properties of granular bentonite, a candidate gap-filling material, were investigated, and their effects on the temperature change of the buffer material were analyzed numerically. Heat transfer by air conduction and convection in the gap were considered simultaneously. Moreover, by applying the Korean reference disposal system, changes in the properties of the buffer material were derived, and the basic design of the engineered barrier system was presented according to the gap filling material (GFM). The findings showed that a GFM with high initial thermal conductivity must be filled in the space between the buffer material and rock. Moreover, the target dry density of the buffer material varied according to the initial wet density, specific gravity, and water content values of the GFM.

• 의료법학
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• 제18권1호
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• pp.199-235
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• 2017

생명공학 연구자들의 중요한 이해 관심 중 하나는 연구를 목적으로, 현재 사용될 수 있거나 미래를 위해 보관될 수 있는 인체유래물을 다루는 것에 관한 논의이다. 본 논문은 인체유래물 연구에서 동의서 없는 폐기용 인체유래물의 재활용을 위한 정당성 모색을 목적으로 한다. 미래의료가 유전체 연구를 통해 예방 의료로 패러다임을 바꿀 것이라는 것은 널리 알려진 사실이다. 선진국들은 인간 유전체 연구를 위해 바이오 뱅크를 설립하여 연구자들을 지원해 오고 있으며, 한국 역시 마찬가지이다. 그런데 현재 한국의 인체유래물 연구자는 기증자의 동의서가 미비된 경우, 인체유래물을 보관할 수는 있으나 사용할 수는 없다. 뿐만 아니라, 인체유래물 연구 자원이 사용 기간이 한정 표시된 동의서로 인해 폐기되기도 한다. 그러나 필자들은 동의서 미비로 인해 현재 폐기되기만을 기다리는 바이오뱅크의 인체유래물이 매우 제한된 조건 하에서는 활용가능하며, 이러한 재활용에 정당한 근거가 있음을 주장한다. 이를 위해 바이오뱅크 및 인체유래물 활용과 관련된 법조문을 고찰하며 동의없는 인체유래물의 활용과 관련하여 제기될 수 있는 윤리적 문제에 대해 검토하고, 바이오뱅크의 폐기용 인체유래물의 재활용 근거를 모색한다.

• 대한치과기공학회지
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• 제38권3호
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• pp.209-216
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• 2016

Purpose: The purpose of this study is to discover the recognition of dental technicians on MSDS and to research the furnishing rate of Material Safety Data Sheet (MSDS) in dental laboratories. Method: 104 dental technicians who were self-written questionnaire. The results were analyzed by SPSS 12.0. The answers to the questionnaire underwent frequency analysis, chi-square test were performed. Results: The result of cross analysis on the occurrence of occupational diseases according to whether MSDS is furnished showed that the group with MSDS furnished had 37.8% of damages due to their occupation, but the group with MSDS unfurnished had 65.7% of damages due to their occupation, which displayed a significant difference(p<0.05). The result of cross analysis on whether the education about chemicals according to whether MSDS is furnished showed there were relatively more responses of no education on the types and characteristics of chemicals, the effect on human body and its risk, emergency measure when exposed to risk, the treating and storing methods and the disposal methods. In addition, there were significant differences on whether all the above education was done between the group with MSDS furnished and the group without MSDS(p<0.000). Conclusion: In order to secure safe working environment of dental technicians and to reduce occurrence of damage caused by chemicals, the related education is necessary. The recognition of dental technicians on MSDS and furnishing rate is increasing but still insufficient, so the related organizations need to establish education and PR measures for prevention of damage.

• 한국환경농학회지
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• 제39권4호
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• pp.281-288
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• 2020

BACKGROUND: Generally, ammonia occurs from agricultural waste disposal. Ammonia is known as a harmful substance to the human body and has a bad influence such as eutrophication on the ecosystem. It is possible to remove the ammonia by ammonia adsorption method using natural zeolite, without external influence. However, due to the natural zeolite shape, it is hard to reuse. METHODS AND RESULTS: Electrospinning method can produce fiber with constant diameter. Moreover, electrospinning method has no limitation for selecting the material to make the fiber, and thus, it is valuable to reform the surface of adsorbent. In this study, reusable membrane was made by electrospinning method. The highest removal efficiency was shown from the membrane with 20% of zeolite included, and it has been verified that it is possible to reuse the membrane through chemical treatment. The highest ammonia removal efficiency was about 92.4%. CONCLUSION: In this study, ammonia adsorption characteristics of zeolite fibers were studied. Electrospinning method can produce zeolite fiber with even distribution. Ammonia can be removed efficiently from ion exchange ability of the natural zeolite. The result of adsorption isotherm indicated that both Freundlich model and Langmuir model provided the best fit for equilibrium data. And study on desorption has demonstrated that the ion exchange from zeolite was reversible when 0.01 M NaCl and KCl solution were used.

• 농촌의학ㆍ지역보건
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• 제1권1호
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• pp.10-21
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• 1976

The traditional application of night soil to vegetable gardens and rice paddies results in a most wide spread condition of parasitism, with a variety of helminths found in Korea. In addition to the above fact, the peculiar habit of the consumption of raw vegetables, fish, crustaceans and mammals provides a means of infestations of helminths. During the last sixty years numerous reports were found on the prevalence of helminths amongst the Korean population in different parts of the country, and it was generally recognized that ascariasis, hookworm disease, filariasis, clonorchiasis and paragonimiasis constitute the important helminthic disease in Korea. In practical measures of parasite control activities the main measures are summarized as mass-treatment, night-soil disposal and transmission control. Among the three, the mass-treatment has been commonly applied, however, no reduction of transmission has been obtained by treatment of a population. Therefore, the ultimate eradication of parasites will depend upon the application of comprehensive environmental sanitation measures. The basic environmental measures will be concerned with (a) the safe disposal of human excreta, (b) the provision of adequate and safe water supplies in such a way as to promote a higher standard of personal hygiene in the population, and (c) the prevention of food contamination by faecal material. Additional environmental measures will deal with the improvement of housing and housing hygiene and with general community development. Community development means social and cultural as well as economic development. The control measures on the parasitic endemic diseases, such as clonorchiasis and paragonimiasis are the good examples for community health development in Korea. The control of Clonorchis and Paragonimus infections are theoretically very simple, as the infection can only invade the human body by way of encysted metacercaria which are taken into the body when eating passive intermediate hosts(fishes, crabs and crayfishes). Although prophylactic measures in the case of the infections deal with above merely consist the fishes in cooking or submerging in hot water before eating them, it is exceedingly difficult to carry out such simple measures in face of century old traditions, to which the relatively primitive population clings with great tenacity. There is no one universally applicable method of control. The choice of methods must be dictated by the nature of the environment. the habit and custom of the people. the pattern of transmission and the resources of the country. There must exist a well organized public health infrastructure. Since a control programme is of necessity on a longterm basis and continuity in its implementation is essential. An investigation should be made on the prevalence of the diseases and its relationships to irrigation engineering, freshwater ecology, agricultural methods, hydro-electric schemes, and the development of communities in affected areas. In conclusion, however. the control of clonorchiasis and paragonimiasis in Korea is not an impossible task. A combination of efforts with major emphasis on health education and mass chemotherapy coupled with governmental aid in enforcing legislative public health measures could reduce the diseases. Health education in particular attempts following four things: (a) It supplies a person with enough general knowledge about a disease to make the preventive measures. (b) It makes a person feel sufficiently about the importance of his own health to make him alter his behavior and adopt these preventive measure. (c) It makes him concerned for the health others. (d) It tries to make him feel so strongly about the first three that be supports and even initiates preventive action by the community. Educational efforts should be directed primarily toward school children because it is during the early years that most persons become infected, and also because children are less entrenched in their food habits so that, the educational process should be involved at various levels in successive changes of knowledge, attitude, beha viour, habit and custom of their lives. The most parasitic endemic diseases are related to community diseases. In caring for a sick community. the first stage is to gather epidemiological data, the next is to make inferences from it-to make the community diagnosis. The third is to prescribe community treatment or community health action part of a community health action programme. The community health action is the sum of the steps decided upon to remedy the critical features revealed by the community diagnosis. Action takes various forms; health education is the most important.