• Environmental Analysis Health and Toxicology
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• v.15 no.1_2
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• pp.19-29
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• 2000

Acetanilide may be released into the environment through air and wastewater from its production and use sites as an intermediate in the synthesis of pharmaceuticals and dyes. Acetanilide is biodegraded rapidly under aerobic conditions and decomposed by indirect photolysis in the presence of OH radicals. An estimated bioconcentration factor of 4.5 suggests that bioaccumulation in aquatic organisms is low. Ecotoxicological data on acetanilide exist on acute toxicity to fishes of 4 species only. According to the EUSES system, the lowest PNEC (Predicted no effect concentration) in fishes is 0.01 mg/1 and PEC (Predicted environmental concentration) for surface water on a regional scale is 9.1$\times$10$\^$－5/mg/l as the worst case. RCR (Risk characterization ratio) of acetanilide for surface water on a regional scale was estimated as 9.1$\times$10-3, which is safe enough for fishes, RCR on a local basis slightly exceeds the value 1 in water and sediment; that is, 1.3 and 1.6, respectively, which suggests the existence of ecotoxicological risk at the vicinity of the manufacturing site. For the refinement of environmental risk assessment on acetanilide, more data should be collected regarding prolonged fish toxicity, acute toxicity toward daphnia and algae. It is, therefore, recommended that acetanilide should be a candidate for further work to supplement the lacking data until it is proved to be safe in the ecotoxicological aspects.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.408-417
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• 2017

The objective of this study is to examine the structural relations between physical self-efficacy, depression, and ego-integrity among the elderly (60 years and older) currently participating in leisure sports. In addition, since the variables affecting ego integrity are presented in a multidimensional manner, it is very important to examine the cause and effect of the variables from an integrated perspective. To achieve this objective, 427 senior citizens attending the leisure sports program of a seniors center were assigned as the research subjects. For the structural equation modeling performed in the study, confirmatory factor analysis and reliability analysis were conducted for each variable, and direct, indirect, and total effects were estimated. The model fit is based on TLI, CFI, and RMSEA, and both the fit of the measurement model and the fit of the research model satisfy the criterion. The results of the analysis are as follows. First, in the results of verifying the validity and reliability of the questionnaire, all the variables of physical self-efficacy, depression, and ego-integrity were suitable. Second, the perceived physical ability had positive effects on depression, current life satisfaction, wise life, and attitude toward life, whereas the physical self-expression confidence had positive effects on current life satisfaction and attitude toward life, but negative effects on acceptance of the past life. Lastly, depression had negative effects on current life satisfaction. The results showed that the elderly identified the integrated relationship of physical self - efficacy, depression, and self-integration.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.12
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• pp.146-152
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• 2016

The purposes of this study were to investigate the effects of professional soldiers' family healthiness on the organizational effectiveness of the military and test for any differences in the structural modeling path caused by the mediating effects of empowerment depending on whether they lived with their families or not. Data were collected with a self-administered survey distributed to 480 professional soldiers after the approval of the Ministry of National Defense. The data collected were then analyzed using descriptive statistics, structural equation modeling, and multi-group analysis. The analysis results show that the family healthiness of all of the professional soldiers had direct or indirect effects on their organizational effectiveness via empowerment and that family healthiness was a variable with a very large explanatory power for organizational effectiveness. Both family healthiness and empowerment had effects on the organizational effectiveness of the solders that were living with their families and those who lived separately from their families. The levels of family healthiness, empowerment, and organizational effectiveness were all high among the professional soldiers that were living with their families and all low among those who were not. Increasing the family healthiness and empowerment was found to enhance the organizational effectiveness in all of the models, and a higher organizational effectiveness would be expected from professional soldiers living with their families. These findings led to a proposal that various plans should be prepared to help professional soldiers live with their families and provide them with family welfare support.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.285-293
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• 2017

This study examined the causal relationship among job stress, fatigue, and job satisfaction, which affect the turnover intention of elderly nursing home care workers. Data were collected from Sep.15 to Sep. 30, 2014. Structured self-administered questionnaires were delivered and collected without the respondents' personal information. The subjects were 232 female care workers working in nursing homes in D city. The data were analyzed using the SPSSWIN 21.0 and AMOS 21.0 programs. Covariance structure analysis was performed to estimate the causal relationship between the variables affecting the turnover intention of care workers. The results of the analysis were as follows. The variables included in this study were fatigue, which comprised 4.9% of job stress. Job satisfaction explained 54.6% of job stress and fatigue. The turnover intention was 46.2% due to job stress, fatigue, and job satisfaction. In other words, job stress, fatigue, and job satisfaction had a direct or indirect effect on the turnover intention of care workers. In conclusion, job stress, fatigue, and job satisfaction affect the turnover intention. Therefore, a policy to improve the work environment and working conditions is needed to reduce the turnover intention of care workers, and fulfill their duties in a stable life time workplace.

• Solar Energy
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• v.2 no.2
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• pp.29-36
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• 1982

The Solar Energy R&D Department of KIER under the auspice of the Korean government is pushing hard on the development of the passive solar technology with high priority for the expeditious widespread use of solar energy in Korea, since the past few years of experiences told us that the active solar technology is not yet ready for massive commercialization in Korea. KIER has completed the construction of the Solar Energy Research & Test Center in Seoul, which houses the major facilities for its all solar test programs. The Center was designed as a passive solar building with great emphasis on the energy conserving ideas. The Center is not only the largest passive building in Korea, but also the exhibit center for the effective demonstration of the passive heating and cooling technology to the Korean public. The Center was designed to satisfy the requirements based on the technical and economical criteria set by the KIER. Careful considerations, therefore, were given in depth in the following areas to meet the requirements. 1) Passive Heating Concepts The Center employed the combination of direct and indirect gain system. The shape of the Center is Balcomb House style, and it included a large built-in sunspace in front. A partition, consists of transparent and translucent glazings, separates the sunspace and the living space. Since most activities in the Center occur during the day time, direct utilization of the solar energy by the living spaces was emphasized with the limited energy storage capacity. 2) Passive Cooling Concepts(for Summer) Natural ventilation concept was utilized throughout the building. In the direct gain portion of the system, the front glazing can be openable during the cooling season. Natural convection scheme was also applied to the front sunspace for the Summer cooling. Reflective surfaces and curtains were utilized wherever needed. 3) Auxiliary Heat ing and Cooling System As an auxiliary cooling system, mechanical means(forced convection system) were adopted. Therefore forced air heating system was also used to match the duct work requirements of the auxiliary cool ing system. 4) Effect ive Insulation & Others These included the double glazed windows, the double entry doors, the night glazing insulation, the front glazing-frame insulation as well as the building skin insulation. All locally available construction materials were used, and natural lightings were provided as much as possible. The expected annual energy savings (compared to the non-insulated conventional building)of the Center was estimated to be about 80%, which accounts for both the energy conservation and the solar energy source. The Center is being instumented for the actual performance tests. The experimental results of the simplified tests are discussed in this paper.

• Korean Journal of Construction Engineering and Management
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• v.14 no.1
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• pp.23-31
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• 2013

Following the U.S sub-prime mortgage crisis and a slump in properties market, the probability is rising that housing investment would not yield high profit as it used to do until early 2000s. For this reason, the nature of properties market is undergoing a change from a source of lucrative investment to a source of a relatively low but stable profit, such as profit-oriented real estate. This trend is likely to promote REITs market, which is a leading product for indirect investment. Until now, the REITs market has been growing slowly compared to a general housing market or financial markets. However, as the importance of risk management based on portfolio theories increases, stable profit generation of REITs can be effective in risk management. This study conducts an empirical analysis on how investment risks can be diversified by including REITs-a source of relatively stable profit in the equity market-in investment portfolio. The analysis results showed that, similar to food and beverage stocks of highly defensive nature, REITs has a relatively weak correlation with KOSPI that reflects the overall market performance. It also showed very low standard deviation in case of minimum variance portfolio. This suggests that including REITs in investment portfolio can be as effective as including food and beverage stocks for risk diversification. Due to uncertainties, investment always accompanies risks, and balancing potential profits and risks is essential.

• Korean Journal of Construction Engineering and Management
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• v.21 no.1
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• pp.70-77
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• 2020

Public conflict in domestic project has been increased and it results in direct and indirect damages. In order to reduce the loss, there have been diverse researches on the public conflict. However, most of researches tend to mainly focus on characteristics of the conflict. Considering the conflict occurred in SOC project, a research of conflict with project characteristics is necessary. In response to consider the relationships between characteristics of project and conflict, this paper aims to present the relative importance of the relationships. We conducted literature reviews and interviews with experts to select main characteristics of projects and public conflicts. Based on the selected four main characteristics each, we analyzed the relationships between them using Fuzzy AHP. The results show that SOC construction project type among project characteristics exerts the most important effect on overall public conflict. Especially conflict factors and conflict phases among public characteristics are critically influenced by project types. The findings provide a foundation for a conflict management reflecting varying public conflicts due to project characteristics.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.3
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• pp.293-304
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• 2011

The purpose of this study was to investigate the displacement and pattern of stress distribution on periodontal ligaments of maxillary first and second molar, and on orthodontic mini-implant (OMI) surface, according to three different insertion angles to the bone surface of OMI using Dragon helix appliance, which is a newly introduced scissors-bite correcting appliance. OMI were placed between second premolar and first molar with three different insertion angles (45, 60, 90 degrees). Displacement and maximum stress distribution area (MSDA) were analyzed by finite element analysis. When the insertion angle to the alveolar bone surface was 90 degrees, maxillary first and second molar both exhibited MSDA at the palatal root apex. Maxillary first molar did not show any significant displacement, while the second molar exhibited intrusive and palatal displacement. On the OMI, as the insertion angle decreased, the MSDA shifted towards the tip, and the amount of displacement had increased. When the OMI was inserted at a 90 degree angle, anchor loss was minimized and scissors-bite correcting effect was maximized.

• Journal of Periodontal and Implant Science
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• v.25 no.3
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• pp.497-517
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• 1995

The cells associated with normal defense mechanism in inflammation release free oxygen radicals, hydroxy radicals, and various protease, all of which can damage the surrounding cells(fibroblasts) and matrix molecules(collagen). The objective of this study was to evaluate the effects of "scavenger" enzyme, superoxide dismutase(SOD). to periodontal ligament (PDL) cells. Human PDL cells were cultured from the teeth extracted for non-periodontal reason. Cultured PDL cells in vitro were treated with SOD and LPS according to dosage and culture times. Cellular activity was exaimed by Microtitration(MTT) assay. The quantitative expression of cellular proliferation by proliferating cell nuclear antigen(PCNA), collagen type I and fibronectin by indirect immunocytochemically stain in PDL cells were done. The results were as follows: 1. As only SOD treated group at 2 and 3 days, PDL cell activity was significantly increased at more than 150U(P<0.05). 2. When LPS(0.5, $5{\mu}g/m{\ell}$) and SOD(more than 150U) were added together, it was significantly increased than LPS only treated and control groups at 2 days(P<0.05). 3. When LPS($5{\mu}g/m{\ell}$) and SOD(150, 300U) were added together, PCNA index was significantly increased than LPS only treated and control groups at 2 and 3 days(P<0.05). 4. When LPS($5{\mu}g/m{\ell}$) and SOD(150U) were added together, collagen type I was significantly increased than LPS only treated and control groups at 3 days(P<0.05). 5.When LPS($5{\mu}g/m{\ell}$) and SOD(300U) were added together, fibronectin was significantly increased than LPS only treated and control groups at 3 days(P<0.05). On the above the results, the SOD in association with collagen type I, fibonectin, and PCNA may afford biological protection to oxy-radicals that were typically liberated during normal inflammatory response. Thus, the exogenous application of SOD may be effective in sthe treatment of the localized breakdown associated with chronic periodontal disease.

• Korean Journal of Social Welfare
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• v.62 no.4
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• pp.349-376
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• 2010

The study intended to explore not only what are the outcomes of employees' participation in corporate philanthropic activities, such as donation or volunteering, but also how their participation achieves the outcomes. In general, a specific corporate context is likely to lead employees to take part in corporate philanthropy in involuntary or passive ways. With this characteristics, employees' donation or volunteering at a working place has an impact on changes in their attitudes toward corporate social philanthropy and organizational commitment. The study also assumes that the changes in employees' attitudes have a mediate effect on their organizational commitment. The study conducted a survey for about 300 employees working at one of corporations in Seoul Metropolitan area. Based on a structural equation modelling analysis, the results showed that there was an indirect relationship between staffs' participations in corporate philanthropic activities and organizational commitment, which was mediated by employees' assessment and attitudes toward corporate philanthropy. Despite a limitation of the study sample, the study provided both an academic ground to discuss on employees' participation in corporate philanthropy, and a practical ground for corporate leaders to strategically consider how to encourage employees to participate in corporate philanthropic activities and to achieve its goal.