• Journal of the Korean Electrochemical Society
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• v.15 no.4
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• pp.222-229
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• 2012

We studied the electrochemical phenomena and increase of capacity according to the polymer composite electrode of two different polymeric materials with different the voltage range and capacity. Polyaniline (PANI) with relatively high voltage and small capacity and poly [1,2] bis-thio[1,8]-naphthylidine (PTND) with slightly low voltage and large capacity were used as polymer composite electrode materials. After PTND was synthesized, PANI was synthesized on the surface of PTND. The synthesis and the fine structure were analyzed by FT-IR, XPS, FE-SEM, and FE-TEM. Charge/discharge capacity and cyclic voltammetry measurements were carried out for the electrochemical performance as a polymer cathode active material for lithium secondary batteries. The discharge capacities of PANI/PTND after 1,5, and 10 cycles at 1.3~4.0 V voltage range and room temperature 167 mAh/g, 90 mAh/g, and 81 mAh/g. When we compared with PANI (80, 67, and 62 mAh/g), the discharge capacity after 10 cycles was improved about 30%. After 50 cycles, the discharge capacity of PANI/PTND was 67 mAh/g.

• Korean journal of communication and information
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• v.80
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• pp.167-192
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• 2016

This study examined the social trauma experienced by direct victims of accidents and each member of the society affected by grand-scale disasters based on the concepts of collective unconsciousness, archetype, and individuation from Jung's analytical psychology, and their experience of therapy through media. For this purpose, the survivors of the disaster of Sewol that occurred on April 16, 2014, family of the deceased, psychological professionals, and general volunteers were selected as the subjects for one-on-one in-depth interviews and focus group interviews. The findings can be summarized as follows: first, the subjects are suffering from different forms of social trauma such as seclusion and anxiety due to primary/secondary incidents, but there is possibility for them to overcome the social trauma as a social community. Second, the archetypes of life and death, mourning and remembrance are showing in the subjects' everyday lives. In particular, it was found that various archetypes are appearing symbolically through the craft activities in which the survivors are participating most actively. Third, the media therapy program for the victims of the Sewol has limitations in various aspects. However, the fact that the craft activities that are not bound by time and space are highly effective manifests that anyone can take advantage of trauma therapy through digital media that are easily found around them. Finally, this study is significant as it verified the possible individuation of social trauma and identified the limitations of media therapy to suggest its development directions.

• KSBB Journal
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• v.20 no.4
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• pp.285-290
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• 2005

Benzophenanthridine alkaloids - sanguinarine, chelirubine, macarpine, and chelerythrine are produced from Eschscholtzia californica (Californica Poppy, used as a sedative by Native Americans) and most of them are derived from dihydrosanguinarine. The properties of sanguinarine are the basis of its antimicrobial activity and its use in chemosurgery and skin cancer excision. For overproduction of sanguinarine from E. californica, yeast extract was used as elicitor and the elicited cell's metabolites were checked. Sanguinarine production was increased intracelluarly about 8 times in the cell and 5 times extracelluarly. We have peformed proteomic analysis of proteins sequentially extracted from E. califormica suspended cells which were cultured with elicitor, an increase of spot intensity was seen at 24 hours following elicitation. These proteins were separated by two-dimensional electrophoresis (2-DE). We found several spots that were expected to be related to benzophenanthridine alkaloids production by comparing the production profiles of metabolites such as sanguinarine. These results demonstrate the use of metabolite analysis as a tool for detecting target proteins related to metabolites production pathway.

• Journal of the Korean Data and Information Science Society
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• v.27 no.3
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• pp.791-801
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• 2016

The purpose of this study is to examine factors affecting the intent of re-employment of inactive registered nurses. This study presents a secondary analysis of data collected in 'Nurse Turnover On-line Survey' by Korean Nurses Association and Korea Institute for Health and Social Affairs in 2014. The analysis shows that 70.9% of inactive RNs has an intent to return to practice, and most of them preferred 'flexible working options' (47.8%) or 'fixed day shifts' (43.3%) as a work pattern. Main reasons for resigning from their last job have been found to be 'high work intensity' (18.8%) and 'difficulties of night shifts' (16.7%). Inactive married RNs who have working histories in a general hospital or a long-term care hospital or have preferences for traditional shift works showed a stronger intent to return to practice than their reference group. Our study shows that, for inactive RNs to return to practice, it is recommendable to adopt various non-traditional working patterns, to make a staffing distribution considering the labor intensity and to develop education programs designed to increase RNs' professional satisfaction.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.190-190
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• 2008

자연적으로 발생되는 파도, 비, 우박 등과 철도, 차량 및 엘리베이터 등과 같은 인위적인 설치, 이동에 의해 발생되는 진동에너지는 우리 일상생활에서 가장 흔하게 발생할 수 있는 에너지원인데, 이러한 진동에너지는 압전 소재를 이용하여 재생 가능하여 최근에는 이에 대한 연구가 활발히 진행되어 왔다. 예를 들면, 미국의 MIT에서는 인간이 걸을 때 신발에 가해지는 압력을 이용하여 전력을 발생시키는 연구를 진행하여 2.9 mW의 전력을 얻었다. 특히 이러한 기술은 인간의 걷기 운동 등과 같은 일상적인 동작으로 필요한 전력을 얻을 수 있고, 세라믹 소자를 이용하기 때문에 전자노이즈가 발생되지 않을 뿐 아니라 반영구적으로 사용할 수가 있어서, 소형 전자기기 등에 서 기존 이차전지를 대체 또는 보완 할 수 있는 기술로 검토되고 있다. PZT계 세라믹스는 높은 유전상수와 우수한 압전특성으로 이러한 압전발전 분야에서 가장 널리 사용되어지고 있다. 하지만 에너지 효율을 높이기 위하여 적층 구조의 제작 시 구조적 특성상 내부전극이 도포된 상태에서 동시 소결이 필요한데, $1000^{\circ}C$ 이상의 높은 소결온도 때문에 소재 원가가 낮은 Ag전극 대신 값비싼 Pd나 pt가 다량 함유된 Ag/Pd, Ag/Pt 전극이 사용되고 있어 경제성이 떨어지는 단점을 갖게 된다. 순수 Ag 전극을 사용하거나 Ag의 비율이 높은 내부전극을 사용하기 위해서는 $900^{\circ}C$ 이하에서 소결되고 우수한 전기적 특성을 보이는 압전 세라믹스 소재를 개발 하는 것이 필요하다. 따라서 본 연구에서는 압전특성이 우수한 $(Pb_{1-x}Cd_x)(Ni_{1/3}Nb_{2/3})_{0.25}(Zr_{0.35}/Ti_{0.4})O_3$ 계의 조성을 설계하고, 소결온도를 낮추기 위해서 2 단계 하소법을 이용하였다. 또한 $MnCO_3$, $SiO_2$, $Pb_3O_4$ 등을 소랑 첨가하여 액상 소걸 특성을 부여하여 소결 온도를 감소시키려는 시도도 하였다. 소결체의 전체적인 제조 공정은 일반적인 벌크 세라믹의 소걸 공정을 따랐다. 최종 소결된 시편을 XRD분석을 통하여 상을 확인하였고 SEM을 이용하여 미세조직을 관찰 하였다. 전기적 특성을 평가하기 위하여 두께를 1mm로 연마한 시편에 Ag 전극을 도포하여 $650^{\circ}C$ 에서 열처리한 후, 분극처리 하였다. Impedance analyzer를 이용하여 압전 특성 (전기기계결합계수 및 기계적품질계수)을 측정 하였고, 압전전하상수는 $d_{33}$-meter로 측정하였다. 본 연구에서는 압전체에 가해지는 하중의 크기, 시편의 크기, 하중을 가하는 방법, 에너지 저장회로의 최적화 등을 다양하게 시도하면서 에너지 변환 및 저장 효율을 평가하였다.

• Journal of the Korean Electrochemical Society
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• v.19 no.3
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• pp.114-121
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• 2016

This study investigates a CFD modeling of the charge-discharge behavior due to heat generation during charge-discharge cycles of a Li-ion secondary battery(LIB). Present LIB system adopted a current-density equation, heat and mass transfer governing equations upon the 1-dimensional system to the thickness direction for the rectangular pouch configuration. According to the 3-kinds of the charge-discharge current densities of 1C($17.5A/m^2$), 3C($52.5A/m^2$) and 5C($87.5A/m^2$) subject to a 3 V of cut-off voltage, a constant-temperature system at 298 K and three different heat generating systems were analyzed with comparison. Battery capacity decreases with increment of charge-discharge densities not only at the constant-temperature system but also at the heat-generating system. The time for charge-discharge cycles increases at the heat-generating system compare to the constant-temperature system. These trends are considered that the increase of temperature due to heat generation causes the decrement of equilibrium potential of electrodes and the increment of diffusivity of Li ions. Furthermore, cooling effects were discussed in order to control the influence of heat generation due to charge-discharge behavior of a Li-ion secondary battery.

• Korean Journal of Social Welfare
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• v.68 no.4
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• pp.143-167
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• 2016

While there have been numerous studies on various issues of aging of the individuals and the population, little is known about the process and consequences of aging of the disabled. Aging is irreversible for the disabled as well as for the not-disabled. With the advances of age, the disabled confront double jeopardy from disability and old age. This study aims to explore the meaning of aging and death for 40s and 50s living with disability for more than 20 years. It utilizes the data set collected through focus groups discussions of the disabled The cases in our analysis are composed of the disabled capable of articulating their feelings and thoughts. Thus, they are selected from the less privileged ones. The analysis shows that aging of the disabled, often involving secondary disability, overwhelms their current disability. Nonetheless, it does not necessary mean that they become an ordinary elderly person. Rather they still feel exclusion from the elderly for their disability. As getting older they turn to face social barrier for both disability and old age. Also, they are trying to live their present lives in full while accepting the presence of death Our findings are hoped to help to understand how the disabled get old and view their death in their own way.

• Journal of Plant Biotechnology
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• v.36 no.1
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• pp.59-63
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• 2009

Calcium ion ($Ca^{2+}$) is thought to play the important role as a second messenger for signal transduction that results in various physiological responses to cope with developmental programs and environmental changes in plant. In plant cells, the central vacuole functions as a major calcium store, which is important for both signal transduction and preventing cytotoxicity. Although there is evidence for the biochemical characterizations of a calmodulin-regulated $Ca^{2+}$-ATPase (ACA11) localized to vacuole membrane, the biological function to ACA11 in plant has not been verified. In this study, we show that the cell death as the hypersensitive response (HR) in mature leaves is induced in transgenic plant of a vacuole ACA-type $Ca^{2+}$-ATPase, ACA11. Evidence that cell death phenotype is the result of ACA11 gene silencing is provided by Western blot assay using membrane fraction proteins extracted from transgenic plant. The 3, 3'-diaminobenzidine (DAB) staining study provides that the cell death is caused by the increase of reactive oxygen species (ROS) in mature leaves of transgenic plants.

• Journal of Preventive Medicine and Public Health
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• v.34 no.2
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• pp.109-118
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• 2001

The purpose of this review is to discuss the debate concerning the interpretation of epidemiologic studies on particles and health effects. Study of the 1952 air pollution disaster in London established that very high levels of particulate-based smog can cause dramatic increases in daily mortality. However, recent epidemiologic studies have reported statistically significant health effects and mortality due to low levels of air pollution. The statistical significance does not prove causation in observational studies; therefore it is necessary to evaluate these associations. There are arguments for and against each of the numerous studies using Hill's criteria, however the body of accepted evidence supports the causal association. In particular, a high level of consistency in the estimated effect of PM10 has been observed across studies worldwide. The mechanism of the relationship between air pollution and health effects is not obvious. The mechanism of particle-induced injury may involve the production of an inflammatory response by the particulate. The harvesting and the threshold effect are also major concerns regarding the health effects of air pollution. However, current epidemiologic findings indicate that linear models lacking a threshold are appropriate for assessing the effect of particulate air pollution on daily mortality even at current levels.

• Journal of Life Science
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• v.19 no.10
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• pp.1410-1416
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• 2009

The present study aims to examine the effect of turbid water on fishes in streams which branch into a turbid water area (Yeongyang-gun) and a non-turbid water area (Cheongsong-gun), and finally flow into the Imha reservoir. In a comparison of water quality, the chemical status of the water showed higher pH, DO and SS in the turbid water area than in the non-turbid water area. Also, high density of clay minerals such as vermiculite (V) and illite (I), which is from clay mineral leakage during rainfall, was detected in turbid water, resulting in an increase of turbidity. Fishes inhabiting the turbid water showed irregular spaces in gill lamella, cell separation, edema, and clubbing in epithelial tissues. Also, the gill surface showed roughness and plenty of muddy debris substances inside the gills. The Bowman's space was expanded because of contraction of the glomerulus in the Bowman's space of the kidney tissues. Antioxidant enzymes such as SOD, CAT, GPX, and GST showed higher activities in the specific tissues, muscles and kidney, of fishes living in turbid water than in the non-turbid area. We suggested that; first, the antioxidant activities were increased due to removal of harmful radicals generated in fish bodies in the turbid water area, second, long-time exposure of these histological changes in the tissues might have induced secondary lesion accompanying the inaccurate physiological constancy of fishes.