The Korean military has sought to build an all-round military force against the national and international security environment and future asymmetric threats as well as the military threats it faces. However, while raising the need for timely electrification, there are few cases of quantitatively evaluating the loss when electrification is delayed, making it difficult for our military to provide a logical basis to support the importance of the electrification period. Therefore, through this study, we tried to analyze the index of loss cost that can support the need for timely electrification with logical and quantitative data and present it as a logical basis. To this end, the loss cost was calculated in terms of combat efficiency, equipment utilization rate, and maintenance requirements, which can be quantitatively calculated based on “combat readiness,” a general impact on the military in case of delayed timely electrification.

Iron is an essential nutrient for mammalian cells. Most iron absorption occurs in the duodenal epithelial cells and is regulated by hepcidin, which is produced and secreted in the liver. High hepcidin levels can cause iron deficiency anemia due to iron absorption failure. Inside the cell, iron conjugates with a porphyrin ring and is placed with an iron coordinated to heme. One of the heme-binding proteins, known as progesterone receptor membrane component 1 (Pgrmc1), is a non-canonical progesterone receptor associated with diverse molecular gene regulation. Previous studies showed that Pgrmc1 is related to iron homeostasis via hepcidin; however, these mechanisms remain to be elucidated. In the present study, to investigate the role of Pgrmc1 in mammalian iron metabolism, we introduced Pgrmc1 knockout (KO) mice and performed molecular biological analyses using qPCR and western blotting. Pgrmc1 deficiency decreased Hamp mRNA expression and hepcidin protein levels. However, Pgrmc1 deficiency failed to decrease Hamp transcript expression and hepcidin protein levels in siPGRMC1-transfected HepG2 cells and primary Pgrmc1 KO hepatocytes, respectively. PGRMC1 knockdown cells revealed low HAMP mRNA levels upon cyclic AMP (cAMP) activation, suggesting that PGRMC1 promotes HAMP mRNA transcription via cAMP activation. It has been implicated that hepatic Pgrmc1 cannot control hepcidin directly; however, the internal environment caused by the lack of Pgrmc1 may potentially cause low hepcidin levels.

본 연구는 대학생들이 받는 스트레스와 탈모와의 관련성, 탈모 인식 현황을 파악하고, 유형별 스트레스와 탈모 인식의 상관관계를 분석하는데 목적을 두고 경기도 지역 대학생들을 대상으로 245부의 설문지를 회수하여 SPSS 통계 패키지를 이용하여 분석하였다. 연구 결과 탈모로 인한 가장 큰 문제는 ‘자 신감 상실’로 분석되었고, 특히 진로/취업과 학업에 대한 스트레스가 큰 사람일수록 ‘자신감 상실’에 대한 문제를 가장 심각하게 생각하고 있는 것으로 분석되고, 탈모 인식에 대한 일반적 특성과 ‘최근 가장 큰 스 트레스’ 항목의 교차분석 결과와 유형별 스트레스와 탈모 인식을 구성하는 탈모 현황의 상관관계분석 결과 모든 유형의 스트레스가 대학생 탈모에 영향을 미치는 것으로 분석되었다. 그중 가장 큰 영향을 미치는 스 트레스는 진로/취업 스트레스와 학업 스트레스인 것으로 나타났고, 탈모가 생겼을 경우 대인관계나 경제적 문제에 앞서 진로/취업, 학업, 외모를 위해 보다 더 적극적으로 탈모 치료에 임할 의향이 있는 것으로 분석 되었다. 따라서 본 연구는 스트레스를 유형별로 분류하고, 탈모 인식에 있어서 탈모 현황, 탈모 관리, 탈모 치료의 3가지 항목으로 구체화하여 실증적 연구 방법을 통해 상관관계를 분석하였다는 점에서 큰 의의가 있다고 판단된다.

This study investigated the noise reduction effect according to the structure of the sound-absorption and insulating materials in order to maximize the noise reduction effect in various noise environments. For this purpose, the transmission loss according to the change in hole size of the performated plate in sound-absorption and insulating board was predicted using an CAE model. The sound-absorption and insulating board was modeled and the computation of the transmission loss was performed after applying the physical properties and boundary conditions. The pure sounds of 32Hz to 4,000Hz were generated, and the analysis was performed by changing the diameter and pitch of the perforated plate. It was confirmed that the influence of the diameter and pitch of the perforated plate is closely related to the structure that make up the sound-absorption and insulating material. In order to effectively reduce the variously changing noises, it is believed that a method of improving transmission loss for each frequency band of interest is needed by changing the structure of the sound-absorption and insulating material so that the diameter and pitch of the perforated plate can be changed.

When an earthquake occurs, the severity of damage is determined by natural factors such as the magnitude of the earthquake, the epicenter distance, soil properties, and type of the structures in the affected area, as well as the socio-economic factors such as the population, disaster prevention measures, and economic power of the community. This study evaluated the direct economic loss due to building damage and the community’s recovery ability. Building damage was estimated using fragility functions due to the design earthquake by the seismic design code. The usage of the building was determined from the information in the building registrar. Direct economic loss was evaluated using the standard unit price and estimated building damage. The standard unit price was obtained from the Korean Real Estate Board. The community’s recovery capacity was calculated using nine indicators selected from regional statistical data. After appropriate normalization and factor analysis, the recovery ability score was calculated through relative evaluation with neighboring cities.

최근 국내에서는 꿀벌 대량소실 현상이 2022년부터 전국적으로 발생하고 있다. 우리나라 뿐 만 아니라, 전세계 적으로 양봉산업에 큰 위협이 되고 있는 봉군붕괴현상은 2016년 미국에서 세계 최초로 보고되었다. 국내에서는 2022년 민관 합동조사 결과, 이상기온, 응애, 말벌 등이 주요 원인으로 지목되었다. 대량소실 현상을 보인 양봉농 가와 정상 농가의 병원체 검출 비교 결과, 유의성있게 검출이 증가되는 병원체는 발견되지 않았다. 그러나, Tyrophagus mite, Trypanosome, Lake Sinai virus, Apis mellifera filamentous virus 등의 신종 응애, 원충 및 바이러 스 감염이 추가로 확인되었다. 국내에서 새롭게 감염이 확인된 기생충과 병원체가 대량소실, 나아가 봉군붕괴현 상에 직간접적으로 영향을 주었을 것으로 사료되며, 지속적인 조사와 연구개발을 통해 기후등 환경변화에 따른 신종 질병 검색과 대책을 마련해야 할 것이다.

반려동물은 점차 인간 삶의 중요한 동반자로 자리매김하고 있다. 이에 연구자들은 반려동물 상실과 이에 따른 애도에 주목하고 있다. 반려동물의 상실은 다른 상실과 달리 대개 그 부적응이 오래 지속되는 복합 애도로 나타나는 경우가 많다. 이러한 현상은 사람(vs. 반려동물)과의 관계가 더 중요하다는 사회적 인식에 기인하며, 이는 반려인이 자신의 상실 경험을 타인에게 제대로 이해받지 못한다고 여기게 만드는 일종의 ‘제약’으로 작용한다. 즉, 반려인의 지각된 사회적 제약은 이들의 반려동물 상실에 대한 회복을 저해하고 복합 애도를 유발하는 중요한 원인이 된다는 것이다. 따라서 본 연구는 반려동물의 죽음을 경험한 사람들을 대상으로 지각된 사회적 제약이 초기 상실 이후 적응을 방해함으로 써 그 충격이 복합 애도로 이어지는 과정을 심화시킬 것이라고 가정하였다. 연구 결과, 예상대로 지각된 사회적 제약은 상실의 충격과 복합 애도의 관계를 조절하는 것으로 나타났다. 구체적으로, 반려동물 상실 충격으로 인한 복합 애도는 사회적 제약을 크게 지각할수록 더 강하게 나타나는 경향이 있었다. 본 연구는 반려동물 상실 경험과 애도를 이해하는 데 지각된 사회적 제약이 중요한 역할을 담당함을 보여줌으로써 사회적 인식 변화 및 개선의 필요성을 제안한다.

In a steam turbine system for nuclear power plant, the exhaust loss consists of leaving loss, hood loss, turn-up loss and restriction loss. The exhaust loss during rated power operation of steam turbine equipment is inevitable, but it can be optimized by several factors such as last stage blade length, condenser vacuum and steam velocity. In this paper the relationship between the exhaust loss and electrical output of domestic nuclear power plants was quantitatively evaluated, and ways to reduce this loss were considered.

In buffer, a main component of engineering barrier system (EBS) in the deep geological repository, mass loss is mainly caused by upheave and mechanical erosion. The former is a phenomenon that bentonite in the upper part of the buffer moves to the backfill region due to groundwater intake and swelling. And, the latter is a phenomenon that bentonite on the surface of the buffer moves to the backfill region due to groundwater flow at the interface with host rock as the buffer saturates. Buffer mass loss adversely affects the fulfilment of the safety function of the buffer that is to limit and retard radionuclide release in the event of canister failure. Accordingly, in this paper, we reviewed how to consider this phenomenon in the performance assessment for the operating license application in Finland, and tentatively summarized data required to conduct the analysis for the domestic facility based on the review results. Regarding buffer mass loss, the previous studies carried out in Finland are categorized as follows: 1) experiment on the amount of buffer upheave with groundwater inflow rate (before backfilling), 2) analysis for the amount of buffer upheave with groundwater inflow rate (after backfilling), 3) analysis of buffer erosion rate with groundwater inflow rate, 4) analysis for distribution of the groundwater inflow rate into the buffer for all deposition holes (using ConnectFlow modeling results), and 5) analysis of buffer mass loss with groundwater salinity. Finally, the buffer mass loss distribution table was derived from the results of 1) through 3) by combining with that of 4). Given these studies, the following will be required for the performance assessment for buffer mass loss in the domestic disposal facility: a) distribution table of buffer mass loss for combined interactions taking into account effect of 5) (i.e. 1), 2), 3), and 5) + 4)), and b) Threshold for buffer mass loss starting to negatively affect the fulfilment of the safety function of the buffer. Even though it is judged that the results of this study could be directly applied to developing the design concept of EBS and to conducting the performance assessment in the domestic disposal facility, it is essential to prepare a set of input data reflecting the site-specific design features (e.g. dimension, material used, site, etc.), which include saturation time and groundwater salinity.

Since the time to consider when evaluating leakage of spent fuel dry storage systems is very long, assumptions that continue to leak at the initial leakage rate are too conservative. Therefore, this study developed a dynamic methodology to calculate the change in leakage rate using time-varying variables and apply it to calculate the amount of radioactive leakage during the evaluation period. The developed dynamic methodology was then applied to calculate the leakage radiation source term for a hypothetical dry storage system and used to perform a public dose assessment. When applying the developed dynamic leakage rate evaluation methodology for more accurate confinement evaluation in case of containment damage of dry storage system, it was found that the change of leak rate with time is very insignificant if the hole diameter is small enough, and the leak rate decreases rapidly with time when a hole with a certain diameter or larger occurs. In the case of the accident condition, except when the hole is very large, it corresponds to the chocked flow condition, and the leak rate decreases rapidly as soon as the internal pressure is sufficiently lowered to enter the molecular and continuum flow region. In the case of a small hole diameter, the leakage volume is very small, so even if the dynamic methodology is applied, the evaluation results are not different from the case where the initial leakage rate continues, and when the hole diameter exceeds a certain value, the internal pressure drops according to the leakage volume, and the leakage rate decreases significantly. As a result of evaluating the dose to residents by applying the calculated radiation source term, it was confirmed that the dose criteria was exceeded when a hole with a diameter of about 4 μm occurred under off-normal conditions, and the dose standard was exceeded under accident conditions when a chocked flow occurred between the diameter of the hole and 2-3 μm, resulting in a rapid increase in the dose. The results of this study are expected to contribute to a more accurate evaluation of the confinement performance of storage systems, which will contribute to the design of optimal dry storage systems.

When a loss of coolant accident which causes a partial or a full drainage in the SFP would happen, Zircaloy-4 spent fuel cladding begin to react with high temperature air, and the heat generates by exothermic reaction between Zircaloy-4 cladding and surrounding air. Due to the heat, the ignition may occur in the surface of Zircaloy-4 cladding. If the Zr-fire phenomenon occurs during the accident in a SFP, the spent fuel cladding and pellets would be severely fragmented and powdered and it may bring about a massive release of radioactive source terms. Therefore, it is crucial to prevent the zirconium fire phenomenon for the spent fuel pool safety. However, a main cause to trigger the zirconium fire was not identified. In order to identify a possible mechanism of the Zr-fire phenomenon, OECD-NEA SFP Project I, II was initiated. In this paper, we reviewed the Zr-fire phenomenon which may occur in the spent fuel pool for complete loss of coolant accident scenario. The Spent Fuel Pool Project (hereinafter SFP project) is the experimental program to investigate the phenomena of spent fuel pool complete loss of coolant accident using a 17×17 PWR fuel assembly. In this section, the zirconium fire phenomenon which was observed from the SFP project is briefly investigated. This paper presented the fuel assembly temperature (i.e. zirconium alloy cladding temperature) and oxygen concentration profile of the SFP project phase-1 ignition test. At around 12.7 hour, the temperature abruptly increased and the oxygen concentration also dramatically decreased. This abrupt temperature escalation is the zirconium fire phenomenon. In order to investigate the mechanism of this zirconium fire phenomenon, behaviors of both temperature and oxygen concentration were fully compared. This paper reviewed the results of OECD-NEA SFP project experiment and then a mechanism of Zr-fire phenomenon was dscussed. It seems that the Zr-fire phenomenon might be a consequence of thermal mismatch between heat generation and dissipation. A large amount of heat might be generated by the air oxidation of Zircaloy-4 spent cladding immediately after the kinetic transition which is a breakaway phenomenon. This paper discussed the relationship between the breakaway phenomenon and the Zr-fire phenomenon in case of air oxidation of Zircaloy-4 spent cladding. This paper presents preliminary findings on the Zr-fire phenomenon from the open experiment data of the prototypic spent fuel severe accident scenario. These findings would enhance the understanding of Zircaloy-4 spent cladding air oxidation and severe accident scenario progression in a SFP.

본 연구에서는 DWI 적용 시 X축 거리에 따른 신호 손실과 인공물 발생 여부를 SS-EPI 기법과 비교 분석하여, MS-EPI 기법의 특성을 제시하고 임상 적용 관련 기초자료를 제시하고자 하였다. 3.0T 자기공명영상장치와 팬텀을 사용 하여 자기장 중심축과 좌우 끝 지점 ±3cm, 3번씩 움직여 표준 영상인 T2 강조영상과 SS-EPI DWI, MS-EPI DWI(RESOLVE) 축상면 영상을 획득하였다. 각 동일 부위에서의 SS-EPI DWI, MS-EPI DWI 영상을 T2 강조영상과 감산하여 신호 손실 직경을 측정하여 정량적 분석을 하였다. 정성적 평가는 나이퀴스트 허상과 기하학적 왜곡과 신호 손실, 인공물 발생 여부를 방사선사 3명이 비교평가 하였다. 두 기법 모두 오프 센터(off-center)로 이동할수록 신호 손실구간 또는 기하학적 왜곡이 나타나는데, 특히 MS-EPI 기법에서는 좌우 신호 손실 현상이 매우 증가해 –25, +25 cm 구간에서 는 약 50% 길이가 감소하였다. MS-EPI 기법은 근골격계 질환에서 기존에 매우 높은 영상 유용성을 인정받고 있다. 그러 나 k-공간을 분할 하여 채우는 MS-EPI 기법은 오프 센터의 낮은 공간 주파수 획득 시 위상변동 보정이 안 되어 신호 손실구간이 나타나며, 이에 관한 연구는 전혀 없는 실정이다. 이에 따라 본 연구는 기존의 선행 연구에서의 보여주지 못한 임상적 적용 시 MS-EPI 기법의 문제점을 파악하면서 이러한 정보를 공유하고 추가적인 연구에 토대가 될 수 있는 기초를 마련했다는 점에 의의가 있다.

In hospitals, numerous deaths are reported. Healthcare providers who witness death feel a sense of loss and sadness, and experience a cumulative sense of loss as another loss overlaps before recovery after one person's death. Due to these cumulative feelings of loss, health care personnel experience despair, anxiety, helplessness, exhaustion, guilt, depression, and discontent with their jobs, which can result in job turnover and resignation. Various attempts are being made at the organizational level as a way to alleviate the feeling of loss after end-of-life care by healthcare providers, but the reality is that it is very difficult to provide systematic support within the organization. Therefore, the emotion coaching program for healthcare providers who experience loss and mourning, which started in 2017 at a tertiary general hospital, is a program designed and operated at the organizational level to share and talk about the various emotions experienced after the death of the patient

Currently, as the saturation capacity of wet storage pool for spent nuclear fuel (SNF) of PWR in Korea has reached approximately 75%, Dry Storage Facilities (DSF) are necessary for sustainable operation of nuclear power plants. It is necessary to develop acceptance requirements for the delivery of SNF from reactor storage site to Centralized DSF. To do this end, the mechanical integrity of SNF is directly related to its repacking, retrieving, and transporting/handling performances. And also, this integrity is a key factor associated with the criticality safety that is connected to the damaged status of SNF. According to the NUREG/CR-6835, the NRC expects that the potential for nuclear fuel failures will increase because of the increase of the fuel discharge burnup and the degradation of fuel and clad material properties. Due to such damages and/or degradation, the fuel rods in the fuel assembly may be extracted and empty for following treatments (transportation, storage, handling etc). This condition can have a detrimental effect on the criticality safety of SNF. Thus, this study investigated whether extracted and empty of damaged SNF rod affects criticality safety. In this analysis, it is assumed that up to four fuel rods are missed. As a result of the analysis, As the number of fuel rods miss up to a certain number, the value of multiplication factor value of the fuel assembly increases. In addition, since the fuel rods located at the outermost layer contained relatively less fissile material than the fuel rods located center of the lattice, and neutrons were lost by the absorption material, the effective multiplication factor value gradually decreased. Nevertheless, the criticality safety was assessed to be maintained.