• Environmental Analysis Health and Toxicology
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• v.17 no.1
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• pp.53-61
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• 2002

Histopathological changes and cadmium accumulations in the gills were investigated in crucian carp (Carassius auratus) exposed to 0, 0.01, 0.1, 0.5 mg/1 cadmium (Cd) concentrations for 25 days. After 25 days of exposure. cadmium accumulations increased in each of the different exposure concentrations. Histopathological changes in the gills of curcian carp exposed to cadmium included the acidification of mucous cell, the terminal clubbing of lamellae, the hyperplasia of epitherial cell and the curved of secondary lamellae. The similar histopathological changes were observed once the accumulations of cadmium reached the similar levels found in the present study with the different exposure schemes. Also the acidification of mucous cell in gills appeared when cadmium accumulations reached 5 $\mu\textrm{g}$/g and more. These results suggested that histopathological changes in the gills, an appearance of mucous cell acidification. be used to estimate the relation between toxic effect and cadmium accumulations in the gills.

• Korean System Dynamics Review
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• v.11 no.1
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• pp.85-102
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• 2010

This paper explores the ways in which the functions of local educational authority in Korea can be analyzed by systems thinking, and puts forward some policy leverage strategies to enhance predictability of education policy effects and also to prevent unanticipated side effects arising from it. In dong so, we sketch causal diagrams to depict functional changes of local educational authority, based on before and after comparison, and attempt to derive policy intervention points to minimize unforseen reactions from the stake-holders concerned. These diagrams make it possible for educational policy-makers to capture the feedback, stocks and flows, time delays, and non-linearities they identify, although they have some limitations. This paper concludes that newly-designed functions and structures for local educational authority may be accepted by the stake-holders including teachers and unions, only if complex systems surrounding functional changes regarding local educational authority can be clearly understood and relevant policy measures can be effectively taken before the functional changes happen.

• Journal of the Korean Home Economics Association
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• v.36 no.1
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• pp.13-21
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• 1998

Coping resources may be a crucial aspect in single mothers' and their childrens' adjustment. Using a survey data collected from 275 pairs of single mothers and their children, this study investigated the perceived effects of economic resoures, family relational resources, and social support on positive changes of both mothers and their children. Results revealed that both mothers and their children perceived positive changes of themselves and their children(mothers) relatively high. The degrees of positive changes of mothers were influenced mostly by family relational resources. In the same token, the degrees of positive changes of children were also affected by family relational resources. Overall, the findings suggested the importance of relational resources in explaining the positive changes of single mothers and their children.

• Journal of the Korean housing association
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• v.19 no.6
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• pp.45-53
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• 2008

The purpose of this study was to find out older adults' current uses, satisfaction level and life changes by using digital home services. The study collected data from 140 persons who were 55 years and older living in a digital home. The results of the study showed that consideration level of digital home service installation was the major variable to affect the residents' life changes. In general, the residents who use more digital home services experienced higher positive life changes. Therefore, for older adults, various ideas to expand their understanding of digital home services should be developed to increase their positive life changes.

• Journal of Families and Better Life
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• v.29 no.1
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• pp.55-70
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• 2011

The purpose of the research is to critically review the major changes of marriages and families during the 20th & 21st centuries and its impact on family relations. Especially, three topics that is, changes in the meaning of marriage, changes in the gender role and sexuality, and changes in the life span were reviewed in terms of how those changes had impacts on each family members and who had been influenced most. Also, how those kinds of changes will have influences on marriage and family relations. Finally, based on the review implications and research agendas for the family scholars were added.

• Plant Resources
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• v.8 no.3
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• pp.263-274
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• 2005

We have studied the effects of dampening papers (Dampened paper, Newspaper, Korean paper, Flower sheet), silica gel (30g, 60g) and temperature ($20^{\circ}C,\;25^{\circ}C$) on color changes of Erythronium japonicum. In the treatment of $20^{\circ}C$, color changes were low in treatments with silica gel rather than in a treatment of dampening papers. In particular, newspaper and Korean paper showed much less changes in colors by the combination treatments with 30g of silica gel. Likewise, in the treatment of $25^{\circ}C$, color changes were low in combination treatments with silica gel rather than in a alone treatment of dampening papers. For the combination treatment with 30g of silica gel, low color changes were shown in the divisions of newspaper and Korean paper, while for the combination treatment with 60g of silica gel, low color changes were shown in the those of Korean paper and dampened paper.

• Journal of the Ergonomics Society of Korea
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• v.18 no.1
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• pp.91-108
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• 1999

In our previous work using a motion analyzer and 3-dimensional sonic digitizer, the arm shapes for 23 women in their early twenties were classified into three characteristic types. In order to design sleeves, suitable for arm movements for the three characteristic arm shapes, a relationship between arm length variation and shoulder/elbow angles has been investigated for four cases of arm movements (flexion, extension, adduction and abduction). Each arm movement can be characterized by the changes in shoulder angle and the changes in elbow angle at the maximal shoulder angle. In all the four cases of arm movements, the changes of shoulder length and cap height are largest at the maximal shoulder angle. These changes were little affected by changes in elbow angle. The changes in the lower arm length and the difference between cap height and upper arm length are the largest at the maximal elbow angle of the maximal shoulder angle. There is a linear relationship between cap height and shoulder angle during arm movements; thus, in designing sleeves the cap height can be determined from the regression of cap height vs. shoulder angle.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.4
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• pp.475-483
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• 1998

Structural changes in an economy system bring about serious problems in establishing economic policies. The boom of middle-east export, the oil shock, and the recent dollar crisis in Korean economy are such examples. Hence, it is necessary to identify and estimate those structural changes. This study focuses on an output and price and analyzes structural changes in aggregate demand and supply. The aggregate demand and supply structures are described by conventional dynamic simultaneous equations model, where each structural change is represented by dummy variables and estimated by the proposed Bayesian method. By applying this model to Korean output and price, structural changes in the aggregate demand and supply are analyzed.

• Journal of Ocean Engineering and Technology
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• v.21 no.6
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• pp.59-63
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• 2007

This study discusses the spatiotemporal characteristics of the geomorphological changes in Gwangyang Bay. In this study, we analyzed four aerial photos and nautical charts. The geomorphological changes that have occurred over time were identified using an MGIS (Marine geographic information system) overlay analysis. As a result, we were able to identify the geomorphological changes that have resulted from the coastal development and fairway dredging of Gwangyang Bay. This paper demonstrates that the marine geographic information system can be effective in monitoring the geomorphological changes in coastal zones.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.242-242
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• 2015

Monitoring the land cover changes in Nakdong River Basins using the multi-temporal remote sensing datasets is necessary for preserving properties in the river basins and monitoring the environmental changes in the river basins after the 4 major river restoration project. This research aims to monitor the land cover changes using the multi-temporal Landsat imageries and the airborne topographic LiDAR data. Firstly, the river basin boundaries are determined by using the LiDAR data, and the multiple river basin imageries are generated from the multi-temporal Landsat imageries by using the river basin boundaries. Next the classification method is employed to identify the multiple land covers in the generated river basin imageries. Finally, monitoring the land cover changes is implemented by comparing the differences of the same clusters in the multi-temporal river basin imageries.