The Korea Institute of Nuclear Nonproliferation and Control (KINAC) is developing a simulation model to estimate nuclear material production. This model is a foundational technology in interpretation and evaluation in preparation for denuclearization verification. Through this model, it is possible to estimate the amount of nuclear material that can be produced based on information on the activities of facilities related to the nuclear fuel cycle in the actual denuclearization verification stage. This model makes it possible to determine whether the declared amount of nuclear material is reliable. In addition, the reliability of the reported information can be confirmed through on-site inspection. However, there is a possibility that proliferation-related activities cannot be detected even through this inspection, and a normal state may be misdiagnosed as carrying out nuclear proliferation-related activities. Therefore, it is unreasonable to specify activities related to nuclear proliferation with only one inspection. Since each inspection method has its diagnosis rate and false diagnosis rate, measures such as repeating the same inspection method or combining different inspection methods are required to detect activities related to nuclear proliferation reliably. Therefore, a model capable of estimating the number of repetitions to obtain a reliable nuclear activity detection probability was developed by using each inspection method’s diagnosis rate and false diagnosis rate as input information through a Bayesian inference method. Through this model, it can be concluded that repetitive inspections increase the probability of detecting nuclear proliferation-related activities. This approach confirmed the possibility of repeatedly breaking away from the high-intensity inspection method that causes political and diplomatic resistance from the target country and substituting it with a more readily acceptable, low-intensity inspection method.

Under the Foreign Trade Act, an export license from the Nuclear Safety Commission is required to export items specified in Part 10 of Schedule 2 of the Public Notice of Exportation and Importation of Strategic Items (Trigger List Items). In the case of nuclear materials, deuterium, and heavy water, its cumulative amount determines whether it is trigger list item. An export license is required only if the cumulative amount exported to a single end-user country from January 1st to December 31st exceeds the regulation criteria. The reason for this cumulative control is to exclude small amounts of materials from the scope of control as they are considered less important in view of nuclear proliferation, but to prevent the possibility of acquiring large quantities of materials by importing small amounts several times. As a result, export control of nuclear material, deuterium, and heavy water requires different considerations than other Trigger List Items. First, materials exported by different companies must be consolidated to manage the cumulative amount. Second, it is necessary to continuously follow up the actual export status. If the material is not exported after it was classified as ‘non-Trigger List Items’, it should not be included in the cumulative amount. Third, there may be a difference between the accumulated quantities aggregated at the time of the classification and the time of the actual export. The classification should be changed if an export of the classified material is postponed or another export of same materials occurs before the export of the classified material. Fourth, the classification result of these materials should not be reused. Generally, the classification result could be reused within the expiration date (2 years) but in the case of substances. However, the reuse of classification result for materials should be limited as the classification results could be change depending on the cumulative amount. In addition, the sharing of classification results between different entities should also be restricted. The government approval procedures are required even for export of small amounts of nuclear materials which are less than the regulation criteria. The cumulative quantities of nuclear materials are systematically managed in the Nuclear Export & imPort control System (NEPS) through these procedures. NEPS is also linked to the custom clearance system of Korea Customs Service, which enables to track actual exports and the time of exports. However, cumulative quantities for the heavy water and deuterium are managed individually by classification reviewers. The annual export plans are received in advance from major entities which deal with the materials for nuclear uses, and the cumulative quantities for each application are managed manually. The systematic management has not been required as there were a few cases of exporting small quantities. However, systematic management may be required in the future as overseas expansion attempts from various companies in the nuclear field has been increasing. In addition, further study is needed on the criteria and system for calculating the cumulative amount. The time of aggregate the cumulative amount should be clarified by considering the difference between the time of classification and actual export. It is required to devise an efficient way to follow up the actual export.

A person who performs or plans to conduct a physical protection inspection as stipulated by the law, the act on physical protection and radiological emergency, should obtain an inspector’s ID card certified and authorized by Nuclear Safety and Security Commission Order No.137 (referred to as Order 137). In addition, according to Order 137, KINAC has been operating some training courses for those with the inspector’s ID card or intending to acquire it. Also, strenuous efforts have been put to incrementally elevate their inspection related expertise. Since Republic of Korea has to import uranium enriched less than 20% in order to manufacture fuels of nuclear reactors in domestic and abroad, the physical protection for categorization III nuclear material in transit is significantly important along with an increase in transport. The expertise of inspectors should be constantly needed to strengthen as the increase in transport leads to an increase in inspection of nuclear material in transit. We have suggested a special way to improve the inspector’s capacities through Virtual Reality technology (VR). A 3-Dimensional virtual space was designed and developed using a 3-axis simulator and VR equipment for practical training. HP’s Reverb G2 product, which was developed in collaboration with VALVE Corporation and MicroSoft, was used as VR equipment, and the 3-axis motion simulator was developed by M-line STUDIO corp. in Korea for the purpose of realizing virtual reality. The training scenarios of transport inspection consist of three parts: preparation at the shipping point, transport in route including stops and handover at the receiving point. At the departure point, scenario of the transport preparation is composed with the contents of checking the transport-related documents which should be carried by shipper and/or carrier during transport and confirming who the shipper and/or carrier is. Second, scenario is designed for inspector to experience how carrier and/or shipper protect the nuclear material during transport or stops for rests or contingency and how they communicate with each other during transport. Lastly, scenario is developed focusing on key check items during handover of responsibilities to the facility operator at the destination. Those training scenarios can be adopted to strengthen the capabilities of those with inspector’s ID card of physical protection in accordance with Order 137 and to help new inspectors acquire inspectionrelated expertise. In addition, they can be used for domestic education to promote understanding of nuclear security, or may be used for education for people overseas for the purpose of export of nuclear facilities.

Nuclear fusion energy is considered as a future energy source due to its higher power density and no emission of greenhouse gas. Therefore, various researches on nuclear fusion is being conducted. One of the key materials for the nuclear fusion research is tritium because the D-T reaction is the main reaction in the nuclear fusion system. However, that tritium can also be used for non-peaceful purposes such as hydrogen bombs. Therefore, it is necessary to establish the safeguards system for tritium. In that regards, this study analyzed the possibility of applying safeguards to tritium. To achieve this objective, the tritium production capacity through the light water reactor was analyzed. Tritium Production Burnable Absorber Rod (TPBAR) was modeled through the MCNP code, and tritium production was analyzed. The TPBAR is composed of a cylindrical tube with a double coating of aluminum and zirconium, filled with a sintered lithium aluminate (LiAlO2) pellet to prevent the release of tritium. Tritium is produced by the reaction of Li-6 in the TPBAR with neutrons, and it is extracted and stored at the Tritium Extraction Facility (TEF). As a result, the tritium production increased as the burnup and Li-6 mass increased. In addition, when the tritium produced in this way was transferred to TEF and extracted through the process, the application of safeguards measures was analyzed. To this end, various safeguards measures were devised, such as setting an Material Balance Area (MBA) for TEF and analyzing Material Balance Period (MBP). As there is no designated Significant Quantity (SQ) for tritium, cases were classified based on the type and form of nuclear weapons to estimate the Sigma MUF (Material Unaccounted For) of the TEF. Finally, the comprehensive application of safeguards to tritium was discussed. This research is expected to contribute to the establishment of IAEA safeguards standards related to tritium by applying the findings to actual facilities.

3D printing is widely used in product development and prototype manufacturing, and is expected to become universal across various industries with the development of 3D printing-related technologies. However, parts made by Fused Deposition Modeling(FDM) 3D printing using the commonly used stacking manufacturing process, show low tensile strength and hardness. The decreased mechanical properties of these parts limit their use as structural elements. In this study, we aim to investigate the relationship between ultrasonic treatment of PLA parts produced by FDM 3D printing and their mechanical properties. Specifically, we analyze the effects of ultrasonic annealing on the mechanical properties of PLA parts using the tensile test specimen.

Demand for research on the use of hydrogen, an eco-friendly fuel, is rapidly increasing in accordance with global environmental problems and IMO environmental regulations in the shipbuilding and marine industry. In the case of hydrogen, similar to liquefied natural gas, it has a characteristic that its volume decreases hundreds of times during phase transformation from gas to liquid, so it must be stored in a tank in the form of liquefied hydrogen for transport efficiency. The material of the liquid hydrogen tank is selected in consideration of mechanical properties and hydrogen embrittlement at cryogenic temperatures. In this study, welding research was conducted on STS316L material, which was most commonly used in the space industry. In this study, flux cored arc welding was performed under 4 welding conditions to derive the optimal welding conditions for STS316L material, and then mechanical properties of the welded part were compared and analyzed.

본 연구에서는 마찰모델에 따라 다른 마찰진자시스템(FPS)이 적용된 교량의 성능을 비교･분석하기 위해 구조해석을 수행하였다. 마찰해석모델 별 성능을 분석하기 위해 PVDF/MgO 마찰재의 마찰계수를 활용하여 쿨롱 마찰모델과 속도 의존 마찰모델을 구축했다. 쿨롱 마찰모델은 마찰속도와 관계없이 단일 마찰계수를 사용하며, 속도 의존 마찰모델은 마찰속도에 따른 마찰계수의 변화를 반영하 는 마찰모델이다. 지진해석으로 비선형 시간 이력 해석과 지진 취약도 해석을 수행하여 구조물의 응답을 확인하였다. 마찰모델에 따 른 바닥판과 교각의 지진 응답을 활용해 면진된 교량의 성능을 분석하였으며, 면진된 교량의 성능을 효과적으로 평가할 수 있는 마찰 모델을 분석했다.

The misuse of resources is getting serious every year, and the annual cost of domestic wates disposal announced by the Ministry of Environment is appraching 15 to 23 trillion won, Concerns are mounting that if the situation persists, the saturation of domestic waste landfill in 2025 will not be prevented. As the movement to prevent and solve global environmental problems increases, institutions, companies and individuals are increasingly interested in ‘Upcycle environmenal design’ that considers nature and composes spaces. This study explores solutions to environmental problems caused by waste, focusing on upcycle products and describes the uniform characteristics and effects of upcycle products shown through the analysis. The results of the study are as follows. First, upcycle products are not only treating waste but also protecting the environment at another level. Second, manufacturing upcycle products that take advantage of the original characteristics of packaging material. And third, drawing economic profits from upcycle products as well as the environment. The development of upcycle products according to social consciousness is creating a new environmental design for the surrounding environment(architecture, landscaping, interior, etc) and the movement to think and protect the environment leads to many changes in individual lives beyond institutions and companies. As the movement for environmental protection is expected to become more activement the outlook for upcycle products is also expected to rise further.

Graphite felt is a felt-like porous material made of high-temperature carbonized polymers. It is widely used in electrode materials because of its good temperature resistance, corrosion resistance, large surface area and excellent electrical conductivity. In this paper, the surface functional group modification is of graphite felt electrodes (mainly nitrogen doping modification, nitrogen–sulfur or nitrogen–boron co-doping modification) and surface catalytic modification (metal/ion surface modification and metal oxide surface modification as Main). There are two main methods and research progresses to improve the performance of graphite felt electrodes, and the comprehensive performance of surface functional group-modified graphite felt electrodes and surface catalytically modified graphite felt electrodes are compared respectively. The results show that both surface functional group modification and surface catalytic modification can improve the comprehensive performance of graphite felt electrodes. In this paper, the future development direction of graphite felt activation modification is also prospected.

Along with the development of the automobile industry, the materials and processing technology of parts have also developed. In particular, various materials have been developed and applied to automobile bumpers, which are directly related to crash safety. In particular, the application of composite materials is expanding for weight reduction. In this study, a new composite material made of a mixture of carbon fiber and aramid fiber was developed and the possibility of application to an automobile bumper was reviewed, and significant results were obtained.

세리신은 누에고치에서 추출한 단백질로 많은 건강상의 이점을 가지고 있다. 본 연구는 화장품 소재로서 누에고치에서 유래된 세리신 표준품의 항주름 활성 및 항염증 활성을 평가하기 위해 수행되었다. 세리신의 항산화 효과는 DPPH 및 ABTS 측정법에 의해 측정되었다. 또한 대식세포인 Raw 264.7 cell에서 의 세포 생존율을 확인하였으며, lipoplyscaccharide를 이용하여 유도된 염증반응을 이용하여 세리신의 항 염증 효과를 조사하였다. 그 결과 세리신은 DPPH, ABTS에서 항산화 활성을 보였으며 세포 독성을 가지지 않은 1,000 μg/mL의 농도에서 NO를 억제하였다. 종합하여 세리신은 항산화 활성을 가지며 항노화 및 항 염증 화장품의 우수한 소재가 될 수 있음을 보여준다.

지진은 예상하지 못한 위치와 규모로 지반을 흔들어서 막대한 물적 및 인적 피해를 발생시킨다. 따라서 지진으로 인 한 진동을 최소화하고 피해를 방지하기 위하여 다양한 내진 기술 개발 연구가 수행되고 있다. 최근에는 우수한 성능을 나타내 는 다양한 신소재가 개발되고 있으며 이를 접목된 내진 기술 개발 연구가 하나의 트렌드가 되고 있다. 본 연구에서는 반영구적 이고 자동복원이 가능한 신소재를 적용한 새로운 개념의 영구마찰 자동복원 댐퍼를 제안하고 핵심 부재에 대한 물리적 특성 검 증 연구를 수행한다. 영구마찰 자동복원 댐퍼의 핵심은 복원 특성을 나타내는 초탄성 형상기억합금과 폴리우레탄을 부재로 장 착시키고 추가적인 마찰 특성을 나타내는 네오디뮴 영구자석을 사용하였다. 이러한 핵심 부재는 재료실험을 통해 특성을 검증 하였고 도출된 거동 응답 결과를 통해 영구마찰 자동복원 댐퍼의 구조실험 예측 거동을 도출하였다. 우수한 복원 성능을 나타 내는 영구마찰 자동복원 댐퍼는 최대 하중 성능과 에너지 소산 능력이 우수하여 구조물에 적용 시 강한 지진에도 버티면서 발 생된 손상도 회복 시킬 수 있을 것으로 기대된다.

The most comprehensive and particularly reliable method for non-destructively measuring the residual stress of the surface layer of metals is the sin method. When X-rays were used the relationship of sin measured on the surface layer of the processing metal did not show linearity when the sin method was used. In this case, since the effective penetration depth changes according to the changing direction of the incident X-ray,  becomes a sin function. Since  cannot be used as a constant, the relationship in sin cannot be linear. Therefore, in this paper, the orthogonal function method according to Warren’s diffraction theory and the basic profile of normal distribution were synthesized, and the X-ray diffraction profile was calculated and reviewed when there was a linear strain (stress) gradient on the surface. When there is a strain gradient, the X-ray diffraction profile becomes asymmetric, and as a result, the peak position, the position of half-maximum, and the centroid position show different values. The difference between the peak position and the centroid position appeared more clearly as the strain (stress) gradient became larger, and the basic profile width was smaller. The weighted average strain enables stress analysis when there is a strain (stress) gradient, based on the strain value corresponding to the centroid position of the diffracted X-rays. At the 1/5 max height of X-ray diffraction, the position where the diffracted X-ray is divided into two by drawing a straight line parallel to the background, corresponds approximately to the centroid position.

뷰티미용 기능성 화장품 소재로서 적양배추 잎의 열수와 80% EtOH 추출물의 유리아미노산과 단백질 비 구성 아미노산 유도체의 조성 및 함량을 분석하였다. 열수 추출물의 유리아미노산은 총 14종이 분리되었고, 총 38.37 mg/g 이었으며, 이중 proline이 24.6 mg/g으로 가장 많았다. 또한 필수 아미노산은 6종이 분리되 었고, 총 함량은 3.66 mg/g 이었으며, 이중 valine이 1.59 mg/g으로 가장 많았다. 80% EtOH추출물의 유리아미노산은 총 13종이 분리되었고, 총 17.92 mg/g 이었 으며, 이중 proline이 10.96 mg/g으로 가장 많았다. 필수 아미노산은 5종이 분리 되었고, 총 함량은 1.50 mg/g 이었으며, 이중 valine이 0.56 mg/g으로 가장 많았 다. 또한 열수 추출물의 비 구성 단백질 아미노산 유도체는 총 4종이 분리되었고, 총 1.59 mg/g 이었으며, 이중 ɤ-Aminobutyric acid가 0.99 mg/g으로 가장 많았 다. 80% EtOH 추출물의 경우, 총 2종이 분리되었고, 총 1.66 mg/g 이었으며, 이 중 ammonia가 0.96 mg/g으로 가장 많았다. 따라서 이와 같은 결과로 볼 때, 적 양배추 잎의 열수와 80% EtOH 추출물은 피부와 헤어관리 등의 미용 기능성화장 품 소재로도 활용 가능성이 있을 것으로 사료되며, 또한 이의 결과는 이 분야 연 구에 따른 기초자료로 활용 될 수 있을 것으로 사료된다.