• Nuclear industry
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• v.37 no.8
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• pp.2-5
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• 2017

급작스런 탈원전의 선언은 원자력계를 패닉에 빠뜨리기도 했지만 사실은 뒤돌아볼 새도 없이 앞을 향해 달리기만 한 관성을 거두고 현실을 철저히 분석하여 지금부터 미래까지 최적화된 체질로 개선할 수 있는 처음이자 마지막 기회를 열어준 것이기도 하다. 이제 원자력계는 스스로 책임을 추스르고 안전을 보다 더 강화할 뿐 아니라 사고가 났을 경우 어떻게 하면 부정적 영향을 최소화하고 신속하게 정상 상태로 회복할 수 있는가에 대한 명확하고도 속시원한 시나리오를 제시할 수 있어야 한다. 국민은 원자력계가 어떤 상황에도 흔들림 없이 이러한 숙제를 풀기 위해 어떻게 노력하며 무엇을 준비하며 얼마나 실력을 갖고 있는지 그 부분을 평가한다. 국민이 평가하는 건 원전이 위험한가 아닌가를 뛰어넘어 원자력계가 얼마나 믿을 만한가 아닌가라는 것을 꼭 기억했으면 좋겠다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.22 no.3
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• pp.624-634
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• 1998

The photoelastic model material with shape memory effect and the molding processes for the material are developed in this research. The matrix and fiber of the photoelastic model material developed in this research are epoxy resin (Araldite to hardner 10 to 3 (weight ratio)) and wire of $Ti_50-Ni_50$ shape memory alloy, respectively. It is called Ti50-Ni50 Shape Memory Alloy Fiber Epoxy Composite $(Ti_50-Ni_50SMA-FEC).$ Ti50-Ni50 SMA-FEC is satisfied with the requirements of the photoelastic model material and can be used as a photoelastic model material. The maximum recovering strain of $Ti_50-Ni_50$SMA-FEC is occurred at $80^{\circ}C$ in any prestrain of $Ti_50-Ni_50$ shape memory alloy fiber and in any fiber volume ratio. Recovering strain(force) is increased with the increment of the prestrain and the fiber volume ratio. The best prestrain of $Ti_50-Ni_50$SMA-FEC is 5% for the recovering force among 1%, 3%, 5%.

• Korean Journal of Food Science and Technology
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• v.48 no.3
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• pp.275-283
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• 2016

An anti-amnesic effect of water extract from Dendropanax morbifera Lev. leaves (DMW) on memory dysfunction in streptozotocin-induced diabetic rats was investigated to assess its potential industrial value. Daily administration of DMW (11 weeks) significantly reduced serum glucose, insulin, and blood urea nitrogen (BUN) levels increased by an intraperitoneal injection of streptozotocin (STZ, 55 mg/kg). In addition, the administration of DMW decreased escape latency and increased the time spent in the platform quadrant in the Morris water maze test. Step-through latency in a passive avoidance test was also improved. Finally, DMW produced ameliorating effects on STZ-induced cholinergic deficit through an inhibitory effect on acetylcholinesterase and the increment of acetylcholine level in the hippocampus. These results suggest that DMW might be used as a natural substance for improving diabetic induced cognitive impairment.

• Korean Journal of Social Welfare
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• v.59 no.2
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• pp.65-88
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• 2007

This study evaluates psychometric properties of the Revised Memory and Behavioral Problems Checklist(RMBPC) in Korean version. The sample includes 387 South Korean family caregivers who provide the majority of day to day tasks and emotional care for their older family members with physical and/or cognitive disabilities. The psychometric properties of the RMBPC are verified by item analysis, exploratory factor analysis(EFA) & confirmatory factor analysis(CFA). For cross-validity, the randomly divided two samples are used: one sample for EFA(n=193, 387/2) and the other sample for CFA(n=194, 387/2). The internal consistency of the K-RMBPC is excellent, and the convergent and criterion-related validity of the K-RMBPC with related variables is empirically confirmed. An EFA based on the Principal Component Analysis(PCA) method with varimax rotation explains 65.85% of variance accounted for by the three factors. A CFA also verifies that the model fit was acceptable. The shorter Korean version of the RMBPC is found reliable and valid. The translated checklist would be very useful for clinical and research settings by (a) focusing on observable, conceptually relevant, potentially modifiable behaviors and (b) using objective criteria within a self-administered framework, to enable clinicians and researchers to pinpoint areas of disturbance and target intervention goals for patients and caregivers in a cost-effective manner.

• Journal of Life Science
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• v.29 no.5
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• pp.564-569
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• 2019

Heavy drinking disrupts the nervous system by activation of GABA receptors and inhibition of glutamate receptors, thereby preventing short-term memory formation. Degradation of cognition by alcohol induces blackouts, and it can lead to alcoholic dementia if repeated. Therefore, drugs need to be developed to prevent alcohol-induced blackout. In this study, we confirmed the effect of an ethanol extract of Cassia obtusifolia seeds (COE) on alcohol-induced memory impairment. The effects of COE and ethanol on cognitive functions mice were examined using the passive avoidance and Y-maze tests. The manner in which alcohol affects long-term potentiation (LTP) in relation to the learning and memory was confirmed by electrophysiology performed on mouse hippocampal slices. We also measured N-methyl-D-aspartate (NMDA) receptor-mediated field excitatory synapses (fEPSPs), which have a known association with cognitive impairment caused by ethanol. Ethanol caused memory impairments in passive avoidance and Y-maze tests. COE prevented these ethanol-induced memory impairments in these tests. Ethanol also blocked LTP induction in the mouse hippocampus, and COE prevented this ethanol-induced LTP deficit. Ethanol decreased NMDA receptor-mediated fEPSPs in the mouse hippocampus, and this decrease was prevented by COE. These results suggest that COE might be useful in preventing alcohol-induced neurological dysfunctions, including blackouts.

• Fashion & Textile Research Journal
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• v.24 no.6
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• pp.812-824
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• 2022

This study proposes to develop a 3D printed re-entrant(RE) strip by shape memory thermoplastic polyurethane that can be deformed and recovered by thermal stimulation. The most suitable 3D printing infill density condition and temperature condition during shape recovery for mechanical behavior were confirmed. As the poisson's ratio indicated, the higher the recovery temperature, the closer the poisson's ratio to zero and the better the auxetic properties. After recovery testing for five minutes, it appeared that the shape recovery ratio was the highest at 70℃. The temperature range when the shape recovery ratio appeared to be more than 90% was a recovery temperature of more than 50℃ and 60℃ when deformed under a constant load of 100 gf and 300 gf, respectively. This indicated that further deformation occurred after maximum recovery when recovered at a temperature of 80℃, which is above the glass transition temperature range. As for REstrip by infill density, a shape recovery properties of 100% was superior than 50%. Additionally, as the re-entrant structure exhibited a shape recovery ratio of more than 90%, and exhibited auxetic properties. It was confirmed that the infill density condition of 100% and the temperature condition of 70℃ are suitable for REstrips for applying the actuator.

• Journal of Life Science
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• v.19 no.3
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• pp.317-321
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• 2009

Down syndrome (DS) results from overexpressed genes on an extra copy of human chromosome 21. Among various phenotypes seen in DS patients, mental retardation, such as learning and memory deficits, is a major factor that prevents DS individuals from leading fully independent lives. The Dyrk1A gene that plays a critical role in neurodevelopment has been isolated from chromosome 21, and transgenic mice with over-expression of Dyrk1A show severe hippocampal dependent learning and memory defects. In the present study, as an initial step to test the treatment of Dyrk1A dependent mental retardation phenotypes in model animals, we isolated human Dyrk1A specific lentiviral short hairpin RNA (shRNA) that inhibits the exogenous human Dyrk1A expression, but not the endogenous mouse expression in transgenic mice with human Dyrk1A overexpression. This limited and specific repression of exogenous human Dyrk1A will prove to be valuable information, if Dyrk1A dependent learning and memory defects in DS patients could be treated or at least ameliorated in vivo.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.44 no.1
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• pp.11-17
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• 2024

A seismic structure is an earthquake-resistant design that dissipates seismic energy by equipping the structure with a device called a damper. As research efforts to reduce earthquake damage continue to rise, technology for isolating vibrations in structures has evolved by altering the materials and shapes of dampers. However, due to the inherent nature of the damper, there are an unescapable restrictions on the extent of plastic deformation that occurs in the material to effectively dissipate energy. Therefore, in this study, we proposed a long-life damper that offers semi-permanently usage and enhances structural performance by applying additional tension which is achieved by utilizing super elastic shape memory alloy (SSMA), a material that self-recovers after deformation. To comprehensively understand the behavior of long-life dampers, finite element analysis was performed considering the design variables such as material, wire diameter, and presence of tension, and response behavior was derived to analyze characteristics such as load resistance, energy dissipation, and residual displacement to determine the performance of long-life dampers in seismic structure. Excellence has been proven from finite element analysis results.

• Journal of the Korean Geographical Society
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• v.52 no.1
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• pp.25-53
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• 2017

The ultimate goal of this research is to examine the geographical characteristics of therapeutic spaces where have been appeared in Wa-dong and Gojan-dong, Ansan-si after the disaster of the MV Sewol. As looking into the inside, the aim of the therapeutic spaces, which cover each target group (victims) individually, is various and different because the disaster of the MV Sewol generated various direct and indirect victims requiring healing. The therapeutic spaces are estimated at about 10 organizations and are leaded by private agents predominantly. Furthermore, the therapeutic spaces are located near, but are aside from Danwon high school where many students are reported killed and injured in the incident. And the therapeutic spaces provide simple and repetitive diversions, for example, having a meal, knitting and studying, rather than special programs to restore a broken daily life to the original state. On the basis of such a background, the geographical characteristics of the therapeutic spaces related to the disaster of the MV Sewol can be summarized as follows; first, it seems that target groups accept the therapeutic spaces as the concept of place gradually. Even though most of the therapeutic spaces were suggested by third parties at first, target groups are involved in the management and recollection of their own therapeutic spaces as well as the plan for a future direction now; and consider the therapeutic spaces as exclusive properties. Second, the disaster of the MV Sewol have embedded collective trauma to not only direct victims, but extensive groups such as parents, brothers and sisters, relatives, friends and neighbors as noted earlier. Therefore, the therapeutic spaces support comprehensive target groups; but each therapeutic space is not overlapped each other. However, to solve collective trauma in a local community effectively, the therapeutic spaces are networked closely and build a regular cooperative system. Third, a continuous memory is mentioned as an important point to overcome collective trauma, but some phenomena such as fatigue and conflict with neighbors, out-migrants and a faded atmosphere as time passes act as risk factors in Ansan-si. To keep a continuous memory, the therapeutic spaces attempt the recovery of local communities and devise various events, for example, cultural performances; furthermore, are closely connected with external organizations.

• Korean Journal of Cognitive Science
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• v.26 no.2
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• pp.167-207
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• 2015

This study focused on the awareness and coping methods of psychological trauma and human suffering in the contemporary era after the development of posttraumatic stress disorder(PTSD) including the situations in the Korean society, and proposed principles for an alternative paradigm of trauma recovery. Trauma is defined as an 'external' stress causing chronic suffering mediated by memory, and the American Psychiatric Association approved PTSD in the Diagnostic and Statistical Manual of Mental Disorders in 1980. The development of PTSD empowered moral legitimacy to the victims, opened a successful way to treatment, and accomplished explosive amount of research in the area of neurobiology and cognitive neuroscience. However, this also narrowed the understanding of human suffering, and the importance of an alternative coping method which overcomes the limitations of technical intervention became overlooked. Moreover, the Korean society has an underlying mechanism of replacing the matter of trauma to a problem of an individual. This is shown among the historical context of splitting and denial, and among medicalized bureaucracy. Trauma should be acknowledged as a social suffering, and searching for an alternative paradigm is in need. This study suggested the following principles; seeking for truth and justice, survivor as the agent of recovery emphasizing the responsibility of the community, ecological adaptations of recent bio-psychological achievements, and finally putting emphasis on continuous discussions about the definition of recovery.