• Advances in aircraft and spacecraft science
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• 제3권1호
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• pp.77-93
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• 2016

In this paper, a zero-dimensional mathematical formulation for rapid and explosive decompression analyses of pressurized aircraft is developed. Air flows between two compartments and between the damaged compartment and external ambient are modeled by assuming an adiabatic, reversible transformation. Both supercritical and subcritical decompressions are considered, and the attention focuses on intercompartment venting systems. In particular, passive and active vents are addressed, and mathematical models of both swinging and translational blowout panels are provided. A numerical procedure based on an explicit Euler integration scheme is also discussed for multi-compartment aircraft analysis. Various numerical solutions are presented, which highlight the importance of considering the opening dynamics of blowout panels. The comparisons with the results from the literature demonstrate the validity of the proposed methodology, which can be also applied, with no lack of accuracy, to the decompression analysis of spacecraft.

• 정신신체의학
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• 제5권1호
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• pp.31-42
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• 1997

This study was aimed to investigate dysfunctional attitudes, stress coping strategies and depressive symptoms in psychiatric patients. The subjects of this study consisted of 210 patients(138 schizophrenic patients, 29 depression patients, 43 alcohol dependence patients) according to DSM-IV criteria. Futhermore, the instruments were K-BDI(Beck Depression Inventory-Korean version), DAS(Dysfunctional Attitude Scale) and multidimensional coping strategy scale. The results were the following. 1) There were statistically significant correlations between depressive symptoms and dysfunctional attitudes in psychiatric patients. 2) In terms of coping strategies, there were positive correlations between depressive symptoms and focus on and venting emotions, accommodation, active forgetting, self-criticism, positive comparison, fatalism, passive withdrawal. Whereas, there was significant negative correlation between depressive symptom and active coping. 3) In terms of coping strategies, there were significant correlations between dysfunctional attitudes and focus on and venting emotions, active forgetting, self-criticism, positive comparison, fatalism, passive withdrawal. 4) Depression groups reported significantly higher BDI scores than schizophrenia groups. 5) In depression groups, DAS scores were significantly higher than those in schizophrenia groups. 6) In terms of coping strategies according to diagnosis, there were significant differences in venting emotions, active forgetting and self-criticism. As for venting emotions, alcoholic groups were scored significantly higher than schizophrenic groups. As for active forgetting, depression groups were scored significantly higher than schizophrenic groups. In self-criticism, depression groups and alcohol dependence groups reported significantly higher scores than schizophrenic groups.

• 아동학회지
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• 제23권1호
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• pp.37-54
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• 2002

The purpose of study was to examine child emotion regulation as a function of child's sex, temperament, mother's emotion regulation, and mother's parenting. The subjects were 386 mothers of fifth or sixth graders in Seoul and Kyonggi province. The data were gathered through questionnaires developed for the current study. The major findings were as follows: 1) There were significant sex differences in some categories of child's emotion regulation. 2) The more active the child's temperament, the child showed more negative emotion regulation(venting, aggressive expression, avoidance). 3) Mother's negative emotion regulation was significantly related to the child's negative emotion regulation. 4) There were significant correlations between mother's parenting and child's emotion regulation. That is, mother's positive parenting was related to child's positive emotion regulation. 5) The relationship between mother's emotion regulation and child's emotion regulation was mediated by mothers' parenting.

• 대한가정학회지
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• 제31권4호
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• pp.67-81
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• 1993

The purpose of this study was to measure married women's coping behaviors according to support stress. The data of this study were obtained from 545 married women who were daughter and daughter-in-law. For analysis of data, Factor Analysis, GLM, t-test, Regression, Pearson's Correlation. The results are as follows: 1. Coping behaviors were composed seven factors that are Mental Disengagement, Venting of Emotions, Restraint, Seeking Support, Acceptance, Active Coping, Turning to Religion. 2. Among the sociodemographic variables, relation, age of mother(p＜0.01), income, grown place of supporter, living arrangement(p＜0.05) were variables to have influence on the coping behaviors to support stress. 3. There was high correlation between support stress and the coping behaviors. (γ=.4339) 4. There was significant different between the higher group and the lower group of support stress on the coping behaviors.

• 한국전기전자재료학회논문지
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• 제32권3호
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• pp.256-261
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• 2019

The use of military lithium batteries in this field accelerates the generation of internal pressure because the active materials, lithium and the electrolyte, react to form sulfur dioxide gas. This also reduces the amount of electrolyte. In this condition, batteries can 'vent' or 'explode' especially when completely discharged. Such venting and explosion can be regarded as a safety accident, as toxic gases and shrapnel are ejected from the batteries which can harm the user. A DTaQ was carried out in 2017 as a quality problem solution project to solve this safety issue. A protection circuit was thereby developed, which included a micro controller unit (MCU) which can stop battery usage when in an over-discharging state by sensing its low-voltage condition. In 2018, this concept was expanded to lithium batteries for the remote controlled ammunition system. This paper reports results of the improved performance.

• 한국산학기술학회논문지
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• 제19권6호
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• pp.154-159
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• 2018

도시가스 회사는 설비의 유지보수 및 점검을 수행할 경우에 가스를 방산하는 경우가 있는데, 가스누출 오인으로 신고 및 주민불안이 발생하게 됨에 따라 활성물질을 통한 천연가스의 부취냄새를 효과적으로 탈취하는 방법을 연구하는데 그 목적을 두었다. 본 연구에서는 천연가스 부취냄새 탈취를 위해 활성물질인 차아염소산나트륨을 이용한 산화법을 통해 천연가스 부취제와 활성물질간 효율적 혼합방법을 위해 간이 탈취방산장치를 제작하여 현장에서 실험을 통해 부취농도를 확인하였다. 탈취실험장치의 기본원리는 방산되는 가스(0.8~1.0MPa)의 에너지를 이용하여 활성물질용액이 첨가되도록 하여 가스 내 부취제와 혼합과정을 거친 후 방출구를 통해 대기로 방산된다. 도시가스 부취제의 활성물질인 차아염소산나트륨을 이용하여 산화반응을 통해 벤츄리와 혼합용기의 직렬연결방식을 적용하여 제작한 장치를 통해 현장에서 효과적으로 부취냄새를 제거할 수 있었다. 하지만, 실질적인 효과를 거두기 위해서는 도시가스의 다량과 고압에서 방산되는 조건에서의 적용하는 문제해결 과제가 남아 있다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 춘계학술대회
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• pp.663-666
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• 2005

Gas hydrates are ice-like compounds that form at the low temperature and high pressure conditions common in shallow marine sediments at water depths greater than 300-500 m when concentrations of methane and other hydrocarbon gases exceed saturation. Estimates of the total mass of methane carbon that resides in this reservoir vary widely. While there is general agreement that gas hydrate is a significant component of the global near-surface carbon budget, there is considerable controversy about whether it has the potential to be a major source of fossil fuel in the future and whether periods of global climate change in the past can be attributed to destabilization of this reservoir. Also essentially unknown is the interaction between gas hydrate and the subsurface biosphere. ODP Leg 204 was designed to address these questions by determining the distribution, amount and rate of formation of gas hydrate within an accretionary ridge and adjacent basin and the sources of gas for forming hydrate. Additional objectives included identification of geologic proxies for past gas hydrate occurrence and calibration of remote sensing techniques to quantify the in situ amount of gas hydrate that can be used to improve estimates where no boreholes exist. Leg 204 also provided an opportunity to test several new techniques for sampling, preserving and measuring gas hydrates. During ODP Leg 204, nine sites were drilled and cored on southern Hydrate Ridge, a topographic high in the accretionary complex of the Cascadia subduction zone, located approximately 80km west of Newport, Oregon. Previous studies of southern Hydrate Ridge had documented the presence of seafloor gas vents, outcrops of massive gas hydrate, and a pinnacle' of authigenic carbonate near the summit. Deep-towed sidescan data show an approximately $300\times500m$ area of relatively high acoustic backscatter that indicates the extent of seafloor venting. Elsewhere on southern Hydrate Ridge, the seafloor is covered with low reflectivity sediment, but the presence of a regional bottom-simulating seismic reflection (BSR) suggests that gas hydrate is widespread. The sites that were drilled and cored during ODP Leg 204 can be grouped into three end-member environments basedon the seismic data. Sites 1244 through 1247 characterize the flanks of southern Hydrate Ridge. Sites 1248-1250 characterize the summit in the region of active seafloor venting. Sites 1251 and 1252 characterize the slope basin east of Hydrate Ridge, which is a region of rapid sedimentation, in contrast to the erosional environment of Hydrate Ridge. Site 1252 was located on the flank of a secondary anticline and is the only site where no BSR is observed.

• Journal of the Korean Wood Science and Technology
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• 제17권1호
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• pp.22-54
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• 1989

Seasonal semi-greenhouse type solar-drying of 2.5cm-and 5.0cm-thick lumber of Quercus aliena Blume and Quercus variailis Blume was carried out to investigate the possibility of solar-drying of wood and to decide the active solar-drying period in Korea. In the active solar-drying period obtained solar-dehumidification, semi-greenhouse type solar-, air- and kiln-drying of 2.5cm -thick lumber of oaks were carried out to analyze drying-rates. -defects, and -yield in each drying-method and to calculate daily total absorbed solar-radiation the solar dryers. The energy balance equations were set up, considering all the energy requirements, to analyze the heat efficiencies of semi-greenhouse type solar and solar-dehumidification-dryer. In a seasonal drying the drying rate of semi-greenhouse type solar-dryer was highest in summer, and greater in fall, spring, and winter in order. Solar-drying time was 45% in summer to 50% in winter of the air-drying rime, and more serious drying-defects occurred in air-drying than in solar-drying. In the active solar-drying period. April, May, and June, the average drying rate in solar-dehumidification-drying was 1.0%/day and greater than 0.8%/day in semi-greenhouse type solar-drying. In solar-dehumidification-drying the time required to dry lumber to 10% moisture content was less than 60 days, and solar-dehumidification-drying showed the highest drying-yield, 65.01%, than the other drying methods. The daily total absorbed solar radiations were 8.51MJ on the roof collector and 6.22 MJ on the south wall collector. In the energy blance 69.48% of total energy input was lost by heat conduction through walls, roof. and floor 11.68% by heat leakage, 0.33% by heating the internal structures of the solar-dryer and 5.38% by air-venting. Therefore the heat efficiency of semi-greenhouse type solar-dryer 13.13%, was lower than that of solar-dehumidification-dryer, 14.04%. Solar-drying of lumber in Korea showed the possibility to reduce the air-drying-time in every season and the efficiency of solar-dehumidification drying was higher than that of semi-greenhouse type solar-drying.

• Archives of Plastic Surgery
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• 제49권4호
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• pp.531-537
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• 2022

Wide-awake, local anesthesia, no tourniquet (WALANT) is a technique that removes the requirement for operations to be performed with a tourniquet, general/regional anesthesia, sedation or an anesthetist. We reviewed the WALANT literature with respect to the diverse indications and impact of WALANT to discuss the importance of future surgical curriculum integration. With appropriate patient selection, WALANT may be used effectively in upper and lower limb surgery; it is also a useful option for patients who are unsuitable for general/regional anesthesia. There is a growing body of evidence supporting the use of WALANT in more complex operations in both upper and lower limb surgery. WALANT is a safe, effective, and simple technique associated with equivalent or superior patient pain scores among other numerous clinical and cost benefits. Cost benefits derive from reduced requirements for theater/anesthetic personnel, space, equipment, time, and inpatient stay. The lack of a requirement for general anesthesia reduces aerosol generating procedures, for example, intubation/high-flow oxygen, hence patients and staff also benefit from the reduced potential for infection transmission. WALANT provides a relatively, but not entirely, bloodless surgical field. Training requirements include the surgical indications, volume calculations, infiltration technique, appropriate perioperative patient/team member communication, and specifics of each operation that need to be considered, for example, checking of active tendon glide versus venting of flexor tendon pulleys. WALANT offers significant clinical, economic, and operative safety advantages when compared with general/regional anesthesia. Key challenges include careful patient selection and the comprehensive training of future surgeons to perform the technique safely.

• Nuclear Engineering and Technology
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• 제45권5호
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• pp.605-612
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• 2013

Removal of decay heat from an operating reactor during a prolonged station blackout condition is a big concern for reactor designers, especially after the recent Fukushima accident. In the case of a prolonged station blackout condition, heat removal is possible only by passive means since no pumps or active systems are available. Keeping this in mind, the AHWR has been designed with many passive safety features. One of them is a passive means of removing decay heat with the help of Isolation Condensers (ICs) which are submerged in a big water pool called the Gravity Driven Water Pool (GDWP). The ICs have many tubes in which the steam, generated by the reactor core due to the decay heat, flows and condenses by rejecting the heat into the water pool. After condensation, the condensate falls back into the steam drum of the reactor. The GDWP tank holds a large amount of water, about 8000 $m^3$, which is located at a higher elevation than the steam drum of the reactor in order to promote natural circulation. Due to the recent Fukushima type accidents, it has been a concern to understand and evaluate the capability of the ICs to remove decay heat for a prolonged period without escalating fuel sheath temperature. In view of this, an analysis has been performed for decay heat removal characteristics over several days of an AHWR by ICs. The computer code RELAP5/MOD3.2 was used for this purpose. Results indicate that the ICs can remove the decay heat for more than 10 days without causing any bulk boiling in the GDWP. After that, decay heat can be removed for more than 40 days by boiling off the pool inventory. The pressure inside the containment does not exceed the design pressure even after 10 days by condensation of steam generated from the GDWP on the walls of containment and on the Passive Containment Cooling System (PCCS) tubes. If venting is carried out after this period, the decay heat can be removed for more than 50 days without exceeding the design limits.