Coupled thermo-hydraulic-mechanical (THM) processes are essential for the long-term performance of deep geological disposal of high-level radioactive waste. In this study, a numerical sensitivity analysis was performed to analyze the effect of rock properties on THM responses after the execution of the heater test at the Kamaishi mine in Japan. The TOUGHFLAC simulator was applied for the numerical simulation assuming a continuum model for coupled THM analysis. The rock properties included in the sensitivity study were the Young’s modulus, permeability, thermal conductivity, and thermal expansion coefficients of crystalline rock, rock salt, and clay. The responses, i.e., temperature, water content, displacement, and stress, were measured at monitoring points in the buffer and near-field rock mass during the simulations. The thermal conductivity had an overarching impact on THM responses. The influence of Young’s modulus was evident in the mechanical behavior, whereas that of permeability was noticed through the change in the temperature and water content. The difference in the THM responses of the three rock type models implies the importance of the appropriate characterization of rock mass properties with regard to the performance assessment of the deep geological disposal of high-level radioactive waste.

확산강조 자기공명영상은 초급성기 뇌경색 진단과 뇌종양 진단 및 치료에 매우 유용하지만 뇌줄기 주변에 자화 감수성 인공물이 자주 발생하고 있어 이를 최소화하려는 노력이 필요하다. 확산강조영상은 에코평면영상(echo planar image)을 사용하고 서로 다른 자화 감수성을 가진 구조물들이 인접한 경계면에서 영상의 왜곡을 나타낸다. SENSE(sensitivity encoding) 기법은 자화 감수성 인공물을 감소시킬 수 있다. 본 연구는 뇌 줄기의 해부구조를 모방한 팬텀을 만들어서 확산 강조영상 시 자화 감수성 인공물을 감소시키는 최적의 SENSE 인자(factor)를 알아보았다. 산출된 최적의 SENSE 인자와 현재 임상 값으로 만든 영상을 비교 분석하고, 통계적 유의성을 검증하여 유용성을 알아보았다. 팬텀 실험 결과 SENSE 인자의 크기가 증가할수록 자화 감수성 인공물은 감소하였다. SENSE 인자 2.5, 3.0, 3.5, 4.0을 적용한 영상은 기준 영상 과 같은 크기의 왜곡이 발생하였다. 산출된 SENSE 인자 2.5의 실험군과 1.5을 적용한 대조군 각각 40명의 영상을 비교 분석하였다. SENSE 인자 1.5를 적용한 대조군은 SENSE 인자 2.5를 적용한 실험군에 비해서 자화 감수성 인공물이 더 크게 발생하였고, 통계적으로 유의하게 나타났다. 본 연구를 통해서 뇌 확산강조영상 획득 시 SENSE 인자 2.5를 적용한다 면 진단적으로 더욱 가치가 있는 영상을 얻을 수 있을 것으로 사료된다.

본 논문에서는 역전파 방법 기반 자동미분법을 이용하여 설계민감도를 구하고 이를 응력제한조건을 고려한 위상최적설계에 적용 하였다. 응력제한조건이 있는 위상최적화문제는 특이점(singularity)과 응력의 국부성(local nature of stress constraint)문제, 그리고 설 계 변수에 대한 비선형성의 문제를 포함하고 최적해를 얻기가 매우 힘들다. 특이점 문제를 해결하기 위해서 응력 완화(stress relaxation) 기법을 사용하였고, 응력의 국부성을 해결하기 위해 p-norm을 이용한 전역 응력치를 제한조건에 사용하였다. 설계 변수에 대한 비선 형성을 극복하기 위해 해석적인 방법으로 정확한 설계민감도를 구하는 것이 중요하다. 위상최적설계에서 기존에는 보조변수방법 (adjoint variable method)을 사용하여 빠르고 정확한 설계민감도를 구했지만, 설계민감도를 해석적으로 구해야 하고, 보조평형방정식 을 추가로 풀어야 하는 어려움이 있다. 이를 해결하기 위해서 인공신경망에서 최적 가중치(weights)와 편차(biases)를 구할 때 쓰이는 역전파 기법을 이용하여 설계민감도를 구하고 이를 응력제한조건을 고려한 위상최적설계에 적용하였다. 역전파 기법은 자동미분에 쓰이는 기법으로 목적함수나 제한조건에 대한 설계민감도를 별도의 수식유도 없이 간단하게 구할 수 있는 장점이 있다. 또한, 미분값 을 구하는 역전파의 과정이 보조평형방정식을 푸는 것보다 계산시간이 빠르고 해석적 방법으로 구한 설계민감도와 같은 정확도를 보 여준다

수처리 후 직접 해양으로 배출하는 산업시설 등에서 Hazardous and Noxious Substance (HNS) 농도 변화를 연속 자동 측정하기 위 한 센서의 기본적 성능으로 상온에서도 ppb 수준의 검출이 가능한 센서가 필요하다고 판단하여 기존의 센서의 감도를 높이기 위한 방법 을 제안하였다. 우선 나노입자 박막에 전도성 탄소계 첨가물을 이용하여 필름의 전도도를 높이는 방법과 촉매 금속을 이용하여 표면에서 의 이온 흡착도를 높이는 방법에 대해서 각각 연구하였다. 전도성 개선을 위해서 ITO 나노입자를 활용한 필름에 carbon black을 첨가물로 선택하여, 첨가물 함유량에 따른 센서의 성능변화를 관찰하였다. 그 결과 CB 함량 5 wt% 정도에서 전도성 증가에 의한 저항과 응답시간 의 변화를 관찰할 수 있었고, 유기용제를 대상으로 한 실험에서 검출하한은 250 ppb 정도까지 낮아지는 것을 확인하였다. 또한 액체 중 이 온 흡착도를 높이기 위하여 센서 표면에 촉매로 Au를 스퍼터로 제작한 표면 촉매층을 형성한 시료를 이용한 실험에서 센서의 응답은 20% 이상 증가하고 평균 검출하한은 61 ppm까지 낮아지는 것을 확인하였다. 이 결과로부터 금속산화물 나노입자를 활용한 화학저항형 센서가 상온에서도 수십 ppb 정도의 HNS를 검출할 수 있다는 것을 확인하였다.

Global concerns have grown regarding emerging infectious diseases (EIDs) caused by previously unknown pathogens. Considering that strengthening surveillance capacity for unknown diseases is one of the core capacities for preparedness and early response to EIDs, identifying areas with poor capacity could be beneficial to prioritize regions for the improvement of surveillance. In this regard, we aimed to develop prediction models to identify high risk areas for low surveillance capacity for unknown diseases in a global scale. Unexplained death events reported between 2015 and 2019 were collected from two internet-based surveillance systems, ProMED-mail and Global Public Health Intelligence Network. From the reports, the number of reported unexplained deaths at the first report and the time gap between death and report were extracted as measures for sensitivity and timeliness of surveillance capacity, respectively. Using geographical locations of the reports and published global scale spatial data, including demographic, socioeconomic, public health and geographical variables, we fitted two boosted regression tree models to predict regions with the low sensitivity and timeliness. The performance of prediction model for the low sensitivity showed moderate validity, but in terms of the model for timeliness, the performance was unreliable. Therefore, we provided predicted risk only for low sensitivity. The mean predicted risks of low sensitivity were, respectively, 45.2%, 37.4%, 12.5%, and 3.0% in low-income, lower middle-income, upper middle-income, and high-income countries. Enhancing surveillance capacity in low-income countries is highly required, given the predicted low level of sensitivity despite the importance of early response.

This study is to investigate fuel cladding temperature in a transport system for the purpose of developing a methodology for evaluating the thermal performance of spent fuel. Detailed temperature analysis in the transport system is important because the degradation mechanism of the fuel cladding is generally sensitive to temperature and temperature history. In such a system, the magnitude of the temperature change is determined by examining the temperature sensitivity of fuel assemblies and system components including fuel cladding temperature, considering the material properties, component specifications, component aging mechanism, and heat transfer mechanism. The sensitivity analysis is performed using heat transfer models by computational fluid dynamics for the horizontal transport system. The heat transfer within the system by convection, conduction and thermal radiation is calculated by thermal-hydraulic analysis code FLUENT. The calculation region is divided into a basket cell and a transport cask. The thermal analysis of the basket cell is for predicting the fuel cladding temperature. And the reason for analyzing the transport cask is to provide the boundary condition for the basket cell by reflecting the external environmental conditions. Here, the basket cell containing the spent fuel assembly is modeled on the homogeneous effective thermal conductivity. The purpose of this analysis is to evaluate fuel cladding temperatures for the following four main items. That is the effect of surface emissivity changes in basket due to the oxide layer of the fuel cladding, the effect of degradation of the canister backfill helium gas, the effect of fuel assembly position in basket cell on fuel cladding and basket temperatures in canister, and the effect of using the homogeneous effective thermal conductivity model instead of the fuel assembly in basket cell. As a result of the analysis, the maximum temperatures in basket cells are evaluated for the above four items. Thermal margins for each item are investigated for thermal performance requirements (e.g., peak clad temperature below 400oC).

Cloud-aerosol interactions are one of the paramount but least understood forcing factors in climate systems. Generally, an increase in the concentration of aerosols increases the concentration of cloud droplet numbers, implying that clouds tend to persist for longer than usual, suppressing precipitation in the warm boundary layer. The cloud lifetime effect has been the center of discussion in the scientific community, partly because of the lack of cloud life cycle observations and partly because of cloud problems. In this study, the precipitation susceptibility (So) matrix was employed to estimate the aerosols' effect on precipitation, while the non-aerosol effect is minimized. The So was calculated for the typical coupled, well-mixed maritime stratocumulus decks and giant cloud condensation nucleus (GCCN) seeded clouds. The GCCN— artificially introduced to the marine stratocumulus cloud decks—is shown to initiate precipitation and reduces So to approximately zero, demonstrating the cloud lifetime hypothesis. The results suggest that the response of precipitation to changes in GCCN must be considered for accurate prediction of aerosol-cloud-precipitation interaction by model studies

The study was aimed to investigate the operational meal costs by kindergarten size in Seoul and to analyze recognition for optimal meal prices. A survey (31.6% recovery rate) was conducted on all kindergartens (779 kindergartens) in Seoul on April 2021 using descriptive analysis, t-test, and dispersion method. A price sensitivity measurement (psm) method was used to determine optimal meal prices. Result showed an average food cost for kindergartens of 2,647 won, an average labor cost of 605 won, an average operating cost of 146 won, and the total meal cost of 3,506 won. Total meal cost decreased with increasing kindergarten size (p<0.001). On the other hand, kindergartens with more students decreased the ratio of food cost to total meal cost, and operating cost and labor costs (p<0.001) increased. The optimal price of kindergarten operators' meal cost (OPP) was KRW 3,673. Furthermore, the analysis showed the sensitivity of operators' meal costs to kindergarten size was insignificant.

To rationalize the protection of spent nuclear fuel transport storage cask, we intend to investigate the status of domestic and foreign safety regulations and related technologies to develop sabotage scenarios and analyze the protection performance and radiation impact of transport storage cask. It is essential to conduct an aircraft collision safety evaluation on spent nuclear fuel transportation and storage casks in Korea due to changes in laws and regulations related to nuclear power plant design and demand for enhanced safety. Domestic and foreign research on the protection performance of spent nuclear fuel transport storage cask was based on 9.11 events, and the results of all studies show that the speed of the aircraft and leakage of nuclear materials are insignificant. The Sandia National Laboratory (SNL) calculates Aerosol emissions from spent fuel damage in the event of sabotage and calculates Source Term based on the Durbin-Luna model. In this paper, radiation sensitivity analysis was performed due to damage to the carrier according to the size of the accident, assuming that there was a hole enough to basket from the external shell among the collision scenarios identified for domestic cask models.

Self-Powered Neutron Detector (SPND) is one of devices for in-core fluxes detecting without external electricity source. SPND consisted with emitter, insulator and collector. When neutrons reacted with emitter material, it generates electrons and these electrons cross insulator area to make electric signal in collector area. For calculating sensitivity of SPND with Monte-Carlo code such as MCNP, many physical components must be considered. Cobalt shows that prompt signal and relatively low signal comparing with other delayed signal SPNDs. Initial sensitivity was calculated as 4.28×10−22 A/nv-cm for one electron. Due to Cobalt’s complex decay chain and maintaining high efficiency of SPND, it is necessary to analysis the effect of activation of emitter. Therefore, the DPA (Displacements Per Atom) assessment and activation analysis of the detector components have been evaluated with MCNP 6.2 and ORIGEN-S. With these activation analysis results, that is expected to be used to determine the shielding thickness of the storage system.

To obtain confidence in the safety of disposal facilities for radioactive waste, it is essential to quantitatively evaluate the performance of the waste disposal facilities by using safety assessment models. Thus, safety assessment models require uncertainty management as a key part of the confidencebuilding process. In application to the numerical modelling, the global sensitivity analysis is widely employed for dealing with parametric and conceptual uncertainties. In particular, the parametric uncertainty can be effectively reduced by minimizing the uncertainty of critical parameters in the safety assessment model. In this paper, the numerical model of each step disposal facility (Silo, Near surface, and Trench type) at Wolsong Low and Immediate Level Waste (LILW) Disposal Center is designed by using a two-dimensional finite element code (COMSOL Multiphysics). In order to determine the critical parameters for non-adsorbed nuclides such as H-3, C-14, Tc-99, we introduced the variance-based sensitivity analysis methodology of the global sensitivity analysis. In the case of Silo type, the density of waste is highly sensitive to the total leakage quantity of all nuclides. Additionally, the initial nuclide concentration of H-3 was identified as another important parameter of H-3. On the other hands, the mass transport coefficient showed a high contribution in C-14 and Tc-99. In other types of disposal facilities, the leaking properties of H-3 are significantly affected by the amount of infiltration water. However, C-14 and Tc-99 were found to be more sensitive to the density of waste.

본 연구의 목적은 대학생의 성지식, 성태도와 성인지 감수성과의 관계를 확인하고, 성인지 감수 성에 미치는 영향을 파악하기 위한 서술적 연구이다. 연구 대상자는 139명의 일반 대학생으로 자가 보고 설문지를 통해 수집된 자료는 기술통계, t-test, ANOVA 및 Schffe test로 분석하였다. 일반 대학생의 성지 식 평균은 38점 만점에 22.73점이었고, 성태도는 5점 만점에 2.92점이었다. 성인지 감수성은 평균 5점 만 점에 2.03점이었다. 연구 결과, 성인지 감수성은 성태도와 양의 상관관계가 있었으며(r=.201, p=.018), 일 반 대학생의 성인지 감수성에 영향을 미치는 요인은 성태도(β=.196, p=.021)로 나타났으며, 설명력은 34.0%였다. 본 연구 결과를 토대로 일반 대학생의 성인지 감수성을 높이기 위해 올바른 성태도를 확립할 수 있는 프로그램 개발이 필요하다.

본 연구는 간호사의 장애인에 대한 인식, 장애인 접촉경험, 인권감수성이 장애인에 대한 태도에 미치는 영향을 파악하기 위한 서술적 조사연구이다. 연구의 대상자는 D광역시 소재 2개 대학병원과 C특별 자치시 소재 1개 대학병원에서 근무하는 간호사 181명이었다. 자료는 2021년 9월 2일부터 2021년 10월 6일까지 수집하였다. 수집된 자료는 IBM SPSS 26.0 프로그램을 이용하여 분석하였으며, t-test, ANOVA, Pearson’s Correlation Coefficients, Multiple Regression Analysis로 분석하였다. 대상자의 장애인에 대한 태도에 미치는 영향요인은 장애인에 대한 인식(t=-3.96, p<.001), 장애인환자 접촉유무(t=3.23, p=.001), 인권감수성 중 책임지각능력(t=2.13, p=.035), 장애인인식개선교육 이수 여부(t=2.90, p=.004), 장애인건 강권법 인지 여부(t=2.44, p=.016)이었으며, 30%의 설명력을 보였다(F=9.36, p<.001). 이에 따라 간호사의 장애인에 대한 인식, 인권감수성, 장애인건강권법을 포함한 장애인에 대한 태도를 함양할 수 있는 교육프 로그램 개발이 필요하다.

CALMET (California Meteorological Model), which is a meteorological subroutine for an air quality dispersion mode (CALPUFF; California Puff Model), closely related with the land surface structure. In this study, the sensitivity of micro-meteorological parameters including wind speed and roughness height, Albedo, Bowen ratio, soil heat flux, and leaf area index were closely evaluated with change of land-use in relation to urban development. As a result, although no consistent dependence of roughness height on surface wind was found, it showed that high value of surface roughness could lead to the increase of friction velocity, influence the Monin-Obukhov length and the mixing height. At the same time, the increasing Albedo reduced friction velocity and mixing height. Thus, it was concluded for the CALMET modelling that it is necessary to first define the roughness height, Albedo, and Bowen ratio according to land-use.

사람 아이치바이러스 (Aichivirus A; AiV-A)는 positivesense single-strand RNA 비외피 바이러스로 지난 10년 동안 하수, 강, 지표 및 지상의 다양한 물환경에서 전 세계적으로 검출이 보고되고 있다. 지하수 등 물환경에서 AiV-A 진단을 위한 고감도 및 특이성이 우수한 방법의 개발이 요구됨에 따라, 본 연구에서는 기존 및 신규 설계된 프라이 머 세트를 기초로 역전사 (RT) 및 이중 중합효소연쇄반응이 가능한 조합을 개발하였다. 개발한 방법을 국내 음용 지하수 시료에 적용 및 평가하였으며, 그 결과 지하수 시료에서 AiV-A를 성공적으로 검출 및 동정할 수 있는 RTnested PCR primer sets가 선정되었고 후속적으로 동정할 수 있는 절차가 고안되었다. 본 연구 결과는 지하수 등 물 환경에서 AiV-A 오염을 탐지하기 위한 모니터링 시스템 마련에 기여할 것으로 기대된다.

This study embraces the viewpoint that intercultural sensitivity can be efficiently increased by accepting the communication behaviors(CB) of different groups which are closely related to the components of world views. This study is to examine the CB of North Korean refugees with South Korean people in terms of intercultural sensitivity. It surveyed six North Korean refugees who could share their broad experience of CB. The results show that the participants experienced harsh communication behaviors caused by the dichotomous views, and the stereotypes due to the political impact in denial and defense stages of ethnocentrism. Although the CB based on human empathy in minimization stage was experienced, this situation was made when they tried concealing their origin or putting down their self-esteem. Also, in this stage their revealing the North Korean way of CB inadvertently caused misunderstandings and conflicts. Finally, based on the research findings, this study suggests some ways to accept the CB of North Korean refugees in terms of increasing intercultural sensitivity.

본 연구에서는 전기 근육 자극(electrical muscle stimulation, EMS)에 사용되는 기존의 하이드로겔 패드의 단 점인 사용 편의성, 쾌적성 등을 보완할 수 있는 e-textile (electronic textile)을 이용한 전기 근육 자극(electrical muscle stimulation, EMS) 패드인 EMSCT (electrical muscle stimulation conductive textile)를 연구를 하고자 하 였다. SWCNT (Single-Walled Carbon Nanotube)와   의 농도 및 함침 공정 횟수를 변수로 하여, EMSCT는 5 가지 직물(라디론, 네오프렌, 스판쿠션, 폴리100%, 베르가모)에 전도성을 부여하여 실험이 진행되었다. SWCNT (Single-Walled Carbon Nanotube)와   을 이용한 패딩 공정을 거쳤으며, 교류 측정 결과 하이드로겔 과 가장 유사한 교류를 나타내는 것은 SWCNT:   = 2:1의 베르가모 원단이라는 결과를 얻을 수 있었다. 또한, 편 의성, 사용성, 심리적 만족성에 관한 사용성 평가를 통해 기존 하이드로겔 패드에 비해 EMSCT가 좋은 사용성을 가진다는 결과를 얻을 수 있다.