• 한국환경성돌연변이발암원학회지
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• 제22권4호
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• pp.279-288
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• 2002

According to the epidemiological studies in chromium workers, hexavalent chromium is associated with the risk of lung cancer. Cellular oxidative damages by reactive oxygen species produced by hexavalent chromium exposure may play an important role in the carcinogenesis process. We investigated the availabilities of malondialdehyde measurement for the assessments of oxidative damages from chromium exposure with an experimental inhalation study in vivo. Lipid peroxidation, one kind of cellular oxidative damage, was measured in blood plasma of the rats which inhaled the hexavalent chromium mist for 1, 2 and 3 weeks. The concentrations of malondialdehyde (MDA), the metabolite of lipid peroxidation, in all exposed groups were higher than those of controls with dose-dependant manner. The levels of MDA were also correlated with urine chromium levels of the rats. Therefore, MDA as an indicator of lipid peroxidation could be proper biologic marker for the assessment of the oxidative damage from chromium exposure, which might be involved in carcinogenesis.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2001년도 춘계심포지움 및 학술발표회
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• pp.125-125
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• 2001

It has been hypothesized that environmental estrogens may play roles in the increasing incidence of breast and testicular cancers and another problems of the reproductive systems. Alkylphenols which are widely used as plastic additives and surfactants have been shown to induce estrogenic responses. The E-screen assay was developed to assess the estrogenedity of environmental chemicals using the profiferation effect of estrogens on their target cells as an end point. (omitted)

• Journal of Information Processing Systems
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• 제3권2호
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• pp.64-72
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• 2007

Mobile technology appears promising as a method to promote group performance in circumstances dependent on time, but not member proximity. However, the success of mobile technology in group decision-making situations has not yet been proven. This paper aims to see how mobile technology affects the performance of group decision-making tasks that should be resolved urgently and/or sources of idea are disconnected with on-line network. Laboratory experiment was used to investigate the effects of mobile factors on group decision-making. The results from the experiment supported the proposition that pressures of time and location play a significant role in the assessment of group decision performance measures. We found that the adoption of mobile technology to group decision-making procedures might be competitive when group decision-making tasks are urgent and sources of idea are disconnected with on-line network, even though mobile technology is not a panacea on which to depend when designing group decision-making.

• International Journal of Control, Automation, and Systems
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• 제3권spc2호
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• pp.355-362
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• 2005

Deregulations and market practices in power industry have brought great challenges to the system planning area. In particular, they introduce a variety of uncertainties to system planning. New techniques are required to cope with such uncertainties. As a promising approach, probabilistic methods are attracting more and more attentions by system planners. In small signal stability analysis, generation control parameters play an important role in determining the stability margin. The objective of this paper is to investigate power system state matrix sensitivity characteristics with respect to system parameter uncertainties with analytical and numerical approaches and to identify those parameters have great impact on system eigenvalues, therefore, the system stability properties. Those identified parameter variations need to be investigated with priority. The results can be used to help Regional Transmission Organizations (RTOs) and Independent System Operators (ISOs) perform planning studies under the open access environment.

• 한국주거학회논문집
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• 제11권4호
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• pp.9-22
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• 2000

The residential mobility and the housing choice procedures play a significant role on households welfare. This procedure consists of $\circled1$ Moving motives step, $\circled2$ Housing search step, $\circled3$ Assessment of housing alternative step, $\circled4$ Choice and evaluating after choice step, $\circled5$ Intention to move step. There are linkages with each step. The higher the level of moving motives, the higher the level of housing search efforts. The higher the level of housing search efforts, the higher the level of housing alternative evaluating. The higher the level of housing alternative evaluating, the higher the level of housing satisfaction after they choose a house. The higher the level of housing satisfaction after they choose a house, the lower the level of intention to move. So the whole procedure of housing choice among consumers has a main streaming throughout the steps.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1208-1210
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• 1999

Design & operation power systems for meeting increase of electric power demand is becoming more difficult and complex. Some of limitations of conventional technology can be broken through by the application of superconductivity technology. This paper presents a new concept & image for the configuration of superconducting power system which has introduced superconducting(SC) generator, cable, transformer, fault current limiter(SFCL), SMES, etc. Engineering evaluation of each power apparatus and its assessment of application to power system were conducted. Futhermore, it is pointed that superconducting power system require a new operating condition. This is, SFCL should play a important part of quenching current level coordination to prevent the other superconducting devices from quenching. Its designing & operating condition including SFCL was discussed in viewpoint of quenching current level and insulation coordination of SC coil.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.214-218
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• 2007

With the development of high speed railway, traction motors play a critical role in the operation of railway vehicle. This paper describes the use of 1000 pF coupler as a on-line partial discharge (PD) measurement for the assessment of railway traction motor. The PD tests are performed with developed PD analyzer and the 5 model coils such as thermal, electrical, mechanical and environmental aging respectively at various AC voltages. On-line PD tests using 1000 pF couplers show that PD patterns can be detected successfully at 2.3 kV.

• 생물정신의학
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• 제8권2호
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• pp.233-238
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• 2001

The routine interictal electroencephalogram(EEG) continues to play an important role in the diagnosis and treatment of epilepsy. The clinical investigation of brain disease in the last decade has been marked by dramatic advances in functional imaging, magnetic resonance scanning and digitized EEG. Epilepsy is a disorder of electrical hyperirritability of cerebral cortex and the interictal EEG remains the most convenient means available to demonstrate cortical hyperirritability. The sensitivity and specificity of the EEG in the diagnosis of epilepsy have been disputed. In this review, the type of EEG findings in epilepsy are reviewed and the sensitivity and specificity of interictal epileptiform discharge are discussed. And also the role of EEG in various clinical situations are summarized.

• Toxicological Research
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• 제30권1호
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• pp.1-5
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• 2014

Xenograft models of human cancer play an important role in the screening and evaluation of candidates for new anticancer agents. The models, which are derived from human tumor cell lines and are classified according to the transplant site, such as ectopic xenograft and orthotopic xenograft, are still utilized to evaluate therapeutic efficacy and toxicity. The metastasis model is modified for the evaluation and prediction of cancer progression. Recently, animal models are made from patient-derived tumor tissue. The patient-derived tumor xenograft models with physiological characters similar to those of patients have been established for personalized medicine. In the discovery of anticancer drugs, standard animal models save time and money and provide evidence to support clinical trials. The current strategy for using xenograft models as an informative tool is introduced.

• 아동학회지
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• 제15권1호
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• pp.23-35
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• 1994

This paper investigated children's learning process concerning age and gender, two of the most apparent social roles. The subjects of the study were 72 Korean preschool children between three to five years of age. The Study was designed to examine problems of developmental sequence and horizontal decalage in understanding of these social roles. Two five-step knowledge sequences of age growth and sex constancy were administered utilizing skill theory (Fischer, 1980). Each step in a sequence had different stories of age or sex role with increasing cognitive complexity, but the two sequences were equivalent in complexity. The children were tested under two different assessment conditions:high support condition of elicited imitation and low support condition of free play and the best story. The findings show that, the understanding of age and sex roles develops through the predicted five-step sequences. The understanding of age role seems to develop earlier than that of sex role although the developmental patterns of the two roles are similar. Variations in the children's performances under different conditions were dramatic, especially for the older children.