• Clinical and Experimental Pediatrics
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• v.45 no.12
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• pp.1551-1558
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• 2002

Purpose : Loss of hippocampal interneurons in dentate gyrus has been reported in patients with severe temporal lobe epilepsy and in animals treated with kainic acid(KA). Interneurons contain $Ca^{2+}$- binding protein parvalbumin(PV). The effects of kainic acid on parvalbumin-immunoreactive (PV-IR) interneurons in dentate gyrus were investigated in organotypic hippocampal slice cultures. Methods : Cultured hippocampal slices from postnatal day nine C57/BL6 mice were exposed to $10{\mu}M$ KA, and were observed at 0, 8, 24, 48, 72 hours after a one hour KA exposure. Neuronal injury was determined by morphologic changes of PV-IR interneuron in dentate gyrus. Results : Transient(1 hour) exposure of hippocampal explant cultures to KA produced marked varicosities in dendrites of PV-IR interneuron in dentate gyrus and the shaft of interbeaded dendrite is often much thinner than those in control. The presence of varicosities in dendrites was reversible with KA washout. The dendrites of KA treated explants were no longer beaded at 8, 24, 48 and 72 hours after KA exposure. The number of cells in PV-IR interneurons in dentate gyrus was decreased at 0, 8 hours after exposure. But there was no significant difference in 24, 48 and 72 hours recovery group compared with control group. Conclusion : The results suggested that loss of PV-IR interneurons in dentate gyrus is transient, and is not accompanied by PV-IR interneuronal cell death.

• The Journal of Engineering Geology
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• v.29 no.3
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• pp.329-337
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• 2019

Bottled water companies in Korea are required to conduct an environmental impact assessment of their drinking water supply at least six months before the expiration of their five-year marketing and production license. The water level drawdown, production well water quality, and monitoring well observation results are the most important items that are evaluated in the assessment report. Here we evaluate the relationship between well drawdown and pumping capacity with pumping time from the production wells of bottled water manufacturers located in Cretaceous granite (site A) and Precambrian gneiss (site B). The method to reduce the pumping capacity is more effective in decreasing the drawdown than the method to simultaneously control the pumping and recovery times. Furthermore, the monitoring data from the pH monitoring sensors that were installed in Precambrian gneiss (site C) yield pH values that increase with time and eventually plateau at a certain value. We therefore propose that pH monitoring is either discontinued or improved to provide more reliable and usable results.

• Korean Journal of Social Welfare
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• v.63 no.1
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• pp.217-239
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• 2011

This study explores legislation process of Disability Discrimination Act in S. Korea focusing on social exclusion and participation through social action approach. I can find a thing in common in that both of disability and social exclusion are concerned with the relationship between majority and minority. Therefore we need to lay emphasis on the social model of disability to overcome social exclusion. When we explore the legislation process of Disability Discrimination Act, we recognize that the legislation is mainly due to a great deal of effort of the disabled, especially the Disability Discrimination Act Solidarity of Korea. So researchers need to focus on the social action approach to overcome social exclusion. In addition social workers have to analyze the macrosystem as well as microsystem to overcome the social exclusion of the disabled. Besides the course of macro practice should include the community organization skills focused on the social action approach.

• Composites Research
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• v.31 no.3
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• pp.88-93
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• 2018

In this study, damaged composite laminates were repaired by a stepped patch repair method using halloysite nanotube(HNT) and milled carbon(MC) reinforced composite materials with different amount of the particles. And the mechanical and structural effects of the particles on the interface between the damaged and repair surfaces were analyzed. At this time, after exposing them to a harsh environment of high temperature and humidity for a long time, the recovery rate of the material properties relative to the material forming the damaged plate was compared. As a result, at $70^{\circ}C$ high temperature distilled water, the hygroscopicity of the HNT/GFRP composites was significantly different from that of the MC/GFRP composites. Especially, 0.5, 1 wt. % HNT was added, the moisture absorption rate was the lowest and this was the factor that contributed to the mechanical strength increase. On the other hand, MC showed a high hygroscopic resistance only with a small amount, and the strength was different according to the action direction of the load, and the addition amount was also different.

• The Journal of the Korea Contents Association
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• v.10 no.4
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• pp.216-224
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• 2010

The main purpose of this prospective longitudinal study was to evaluate, according to a standard clinical classification and assessment method, the effect of a standardized manual stretching and therapeutic massage program on patients with clearly defined congenital muscular torticollis. A total of 52 cases of congenital muscular torticollis who were first seen when they were less than one year old and were treated with conservative physical therapy. Before treatment, the patients were divided into one of three clinical groups: (1) sternomastoid tumor group, (2) muscular torticollis group, and (3) postural torticollis group. Of the 52 patients, 32 (61.5%) made up the sternomastoid tumor group; 15 (28.9%) the muscular torticollis group; and 5 (9.6%) the postural torticollis group. Multivariate analysis of the outcomes showed that the duration of treatment was significantly differentiated according to the clinical group (p<0.01), age at presentation (p<0.01), and a passive rotation deficit of the neck (p<0.01). The current study showed that well controlled conservative physical therapy is safe and effective in the treatment of congenital torticollis in about 84.6% of patients who are first seen before the age of one year.

• Applied Microscopy
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• v.34 no.1
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• pp.1-11
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• 2004

The wound healing is very complex biological processing including inflammatory, reepithelialization and matrix construction. According to the biological systematic category, the ability of the healing is very different. Generally healing ability of the lower animal group has been known more excellent compared to its higher group. Therefore, lower animals have been used as the experimental model to explore the mechanism of the wound healing or repair. To verify histochemical characteristics of the wound healing, we have used skin of the frog (Bombina orientalis) as known common amphibian. At day 1, 10, and 16, the mucous substance was very actively synthesized and strong positive by PAS and Alcian blue (pH 2.5). Day 10 after wounding, margin of the wound was gradually strong positive by PTAH staining for detection of collagen synthesis. At 3 to 6 hour and day 23 to 27, we have found the cell division was active through the MG-P staining, in which the concentration and division of DNA in nucleus was green to deep blue color.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.1B
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• pp.74-85
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• 2009

We propose an Agent-based Fault Tolerant Object Group model based on the agent technology and FTOG model with replication mechanism for effective object management and fault recovery. We define the five kind of agents - internal processing agent, registration agent, state handling agent, user interface agent, and service agent - that extend the functions of the FTOG model. The roles of the agents in the proposed model are to reduce the remote interactions between distributed objects and provide more effective service execution. To verify the effectiveness of the proposed model, we implemented the Intelligent Home Network Simulator (IHNS) which virtually provides general home networking services. Through the simulations, it is validated that the proposed model decreases the interactions of the object components and supports the effective fault recovery, while providing more stable and reliable services.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.498-498
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• 2018

가뭄으로 인해 발생할 수 있는 가장 심각한 피해는 용수 부족으로 인한 수자원 시스템의 용수공급 실패이며, 따라서 가뭄 위험도는 사용 가능한 용수의 부족과 관련하여 정량화되어야 한다. 이러한 맥락에서 수자원 시스템의 가뭄 위험도를 평가하기 위해 주로 신뢰도(reliability), 회복도(resiliency) 및 취약도(vulnerability)와 같은 세 가지 이수안전도 평가지표가 사용된다. 이러한 평가지표는 각각 용수공급 실패가 평균적으로 얼마나 자주 발생하는지, 얼마나 오래 지속되는지, 또한 어느 정도의 규모로 발생하는지를 위험도를 정량화하는 것으로, 용수공급 실패사상의 빈도, 지속기간 및 심도를 나타낸다. 본 연구에서 DRI(Drought Risk Index)는 신뢰도, 평가도 및 회복도의 가중평균값으로 정의되며, 이는 지속기간과 심도를 변수로 하는 이변량 가뭄빈도해석과 같은 변수를 공유한다. 본 연구에서는 두 가지 형태의 DRI 를 이용하여 지역 가뭄 위험도 평가 기준 산정 방안을 제시하였다. DRI_O(observed DRI)는 용수부족 시계열을 통해 산정된 공급실패 사상으로부터 산정되며, DRI_D(designed DRI)는 이변량 빈도해석을 통해 산정된 특정 지속기간을 갖는 확률가뭄심도로부터 계산된다. 기후변화 시나리오를 이용해 DRI_O 를 산정함으로써 미래의 이수안전도를 예측할 수 있으며, 이를 DRI_D 와 비교하여 지역의 용수부족으로 인한 가뭄 위험도를 산정하는 방법을 제안하였다. 또한 기존에는 주로 과거 최대 가뭄사상을 목표안전도로 설정하였으나 DRI_D 를 이용하여 보다 현실적인 목표안전도를 설정할 수 있다. 낙동강 권역의 10 개 중권역의 10 개 기후변화 시나리오를 대상으로 분석을 수행한 결과 병성천 유역과 형산강 유역이 각각 최저 및 최고 위험도를 갖는 것으로 분석되었으며, 지역 안전도 기준은 평균적으로 재현기간 5-20 년 사이의 범위를 갖는 것으로 나타났다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.150-156
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• 2017

This study examined the stress recovery length due to the local damage of a 7-wire strand, which is applied widely to PSC (Post Tensioned Concrete) bridges and cable-stayed bridges. The 7-wire strand is a multiple stranded steel of PC prestressing strand. Owing to the nature of the material, it is damaged continuously after completion with corrosion being the main cause of damage. On the other hand, due to its structural characteristics, it is difficult to grasp the degree of damage inside the cable and the pattern of stress variation. In the case of cables applied to bridges, the parts that are susceptible to corrosion are generated depending on the water supply and installation shape, which may cause local damage. This study analyzed the tendency of performance degradation and stress recovery length according to local damage of a 7-wire strand, which is applied mainly to bridge post-tensioning or stay cables. This study developed a computer-based simulation model that was validated with experimental results. The model developed in this study can be used to evaluate the safety level and estimate the remaining life span of P SC bridges or cable-stayed bridges.

• Korean Journal of Social Welfare
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• v.57 no.2
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• pp.119-142
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• 2005

The purpose of this study is to explore and describe of the reality of working poor in Korea. In spite of the increasing attention to the working poor, usual definitions of the working poor have some measurement questions. The definition of the working poor should focus on the key dimensions of work and poverty. This study defines working poor as all "persons who have devoted prior 6 months to working or looking for work and who lived in families with incomes below the poverty threshold". This study also defines poverty threshold based on the both concept of absolute and relative poverty. According to this definition, the working poor are almost equally divided between men and women and the majority of them are of prime working age. These characteristics of working poor are seems to be quite different from common sense. Also, serious deficiencies of human capital contribute to the employment problems of the working poor. Their education levels are much less than those of the working non-poor. The distributions of the employment status, occupation, and industry show also that the working poor are highly concentrated in a few low-wage jobs.