• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.3
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• pp.1288-1295
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• 2012

Korea Ministry of Knowledge Economy has estimated that wind power (WP) will be occupied 37% in 2020 and 42% in 2030 of the new energy sources, and also green energies such as photovoltaic (PV) and WP are expected to be interconnected with the distribution system because of Renewable Portfolio Standard (RPS) starting from 2012. However, when a large scale wind power plant (over 3[MW]) is connected to the traditional distribution system, protective devices (mainly OCR and OCGR of re-closer) will be occurred mal-function problems due to changed fault currents it be caused by Wye-grounded/Delta winding of interconnection transformer and %impedance of WP's turbine. Therefore, when Double-Fed Induction Generator (DFIG) of typical WP's Generator is connected into distribution system, this paper deals with analysis three-phase short, line to line short and a single line ground faults current by using the symmetrical components of fault analysis and PSCAD/EMTDC modeling.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.9
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• pp.5683-5692
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• 2014

This study examined the correlation among the Korean language ability, health promotion behaviors and health status of immigrant women by marriage. Data on the subjects of 148 immigrant women were collected from September to December, 2013. Constructed self-administered questionnaires were used to gather information on the general characteristics of the immigrant women, their Korean language ability, health promotion behaviors and emotional health status. The health examination results of the subjects were used for information on their health status. There were significant differences in the Korean language reading ability, drinking habits, total cholesterol and body mass index between the diseased group and the intact group. An analysis of the relationship between the Korean language ability and health conditions revealed a significant positive correlation between the total cholesterol and neutral fat, but negative correlations between the density of hemoglobin and the total cholesterol, the neutral fat and body mass index. There was a significant negative correlation between the Korean language ability and the level of stress. Based on these results, a program was suggested and developed to decrease the rate of drinking, cholesterol and body mass index of immigrant women and to promote their ability to understand health information and express their diseases properly in the Korean language.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.1
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• pp.43-55
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• 2018

The biggest change in the field of coastal ship safety control since the accident of passenger ship Sewol has been the introduction of the maritime safety supervisor system. With its introduction, the safety control system in coastal passenger ships was changed from consisting of operation managers and marine police to operation managers and a newly-introduced maritime safety supervisor. The safety control system for coastal cargo ships was also converted from relying on ship inspection officers to having a maritime safety supervisor and ship inspection officers. However some negative elements have surfaced due to confusion related to the scope of work in the coastal cargo shipping field. These have been caused by dividing the supervisory agency, a lack of work continuity given non-permanent public official status, low supervisor qualifications overlooking reality, and limitations of the order for improvement to secure seaworthiness. It is essential that the maritime safety supervisor system be solidified to reinforce coastal ship safety control. Therefore, systematic safety control in the coastal cargo shipping industry should be conducted by a single, integrated government agency, and the area covered by the order for improvement to secure seaworthiness should be extended. Also limitations of the supervisor recruitment system due to non-permanent public official status should be simultaneously improved. In addition, it is necessary to upgrade supervisor qualifications to require experience with surveyors of international class, ship captains, and chief engineers.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.1
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• pp.56-67
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• 2018

With the introduction of the maritime safety supervisor system in Korea following the passenger vessel Sewol accident, the safety control system for coastal vessels has been reinforced. A maritime safety supervisor performs marine accident prevention activities by offering periodical or occasional guidance and supervision. When a deficiency is found during guidance or supervision sessions, an order for improvement is issued to rectify the problem by such measures as supplementation or replacement of vessel facilities, improvement of work hours and working conditions for employees, educational and training programs for executives and employees, or the improvement of other affairs relating to maritime safety control. However the present order for navigation suspension by a maritime safety supervisor is limited solely to supplementation or replacement. For this reason, orders for navigation suspension against other facilities is impossible, even if a serious deficiency that could lead to a marine accident such as poor cargo loading conditions or unqualified crew is identified. Therefore, the order for vessel navigation suspension to secure seaworthiness should be expanded to include cargo loading/unloading operations, certificates and documentation, maritime safety management systems, and human elements including emergency drills and working conditions, in addition to the supplementation or replacement of vessel facilities that exists.

• Korean Journal of Psychosomatic Medicine
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• v.22 no.2
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• pp.79-86
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• 2014

Objectives : Shift work disorder occurs when you have difficulties adjusting to a work schedule that takes place during a time which most people sleep. Some people may have diverse psychosomatic symptoms, such as sleep problems, depression, anxiety, and headaches even after the shift work schedule ends. The aims of this study are to compare difference of psychosomatic symptoms between rotating shift and daytime working nurse groups. Methods : Volunteer nurses working in a general hospital were recruited in a general hospital. We collected sociodemographic data. We used questionnaires for headache type, headache frequency, and VAS(Visual Analog Scale) for headache intensity, BDI(Beck depression Inventory) and GSAQ(Global Sleep Assessment Questionnaire). We used Mann-Whitney test and Chi-square test for hypothesis testing. Results : Data collected from 84 women nurses. Rotating shift(N=37) working nurses showed younger, more unmarried, and shorter work periods than daytime working nurses (N=47). Also rotating shift group showed more problems of headache, insomnia, excessive daytime sleepiness, depression and anxiety than daytime group. The above results were statistically significant. Conclusions : The rotating shift work women nurses produced more headache, insomnia, excessive daytime sleepiness, depression, and anxiety than daytime working ones.

• Korean Journal of Psychosomatic Medicine
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• v.25 no.2
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• pp.111-119
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• 2017

Objectives : The purpose of this study is to investigate the effects of stress on psychosocial wellbeing at the time of an outbreak of Middle East respiratory syndrome(MERS) and to investigate the effect of resilience as a mediator on the relationship between stress and psychosocial wellbeing. Methods : Perceived Stress Scale, Psychosocial Wellbeing Index Short Form, and the Conner-Davidson Resilience Scale was implemented for 156 medical persons who worked at the hospital in which exposure to MERS cases had been confirmed and 127 ordinary people. We conducted a Pearson correlation coefficient and a hierarchical multiple regression to confirm the effect of stress on psychosocial wellbeing and the mediating effect of resilience between stress and psychosocial wellbeing. Results : The higher the perceived stress, the lower the psychosocial wellbeing in both healthcare workers and the public. The higher the perceived stress, the lower the resilience and the research results showed that there was a partially mediating effect of resilience in the relationship between stress and psychosocial wellbeing. Conclusions : This study demonstrated that the degree of individual resilience can indirectly give a positive effect on the psychosocial wellbeing when people under the stress by MERS shows adverse effects on psychosocial wellbeing. This suggests that clinical intervention and psychosocial approach aiming at strengthening resilience is important to maintain mental health during crisis development.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.289-293
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• 1997

The effects of different types of additives(sucrose fatty acid ester(SE), oligosaccharide and alum) on 40% nonwaxy rice starch gels stored at $20{\pm}1^{\circ}C$ were investigated by ${\alpha}-amylase-iodine$ method, X-ray diffractometry and differential scanning calorimetry. The addition of SE retarded the retrogradation of gels throughout storage period and the antistaling effect of SE was increased with increasing concentration. Oligosaccharide(0.1%) inhibited the retrogradation, but oligosaccharide(0.1% or 0.5%) retarded the retrogradation at early stage of storage, and stimulated the retrogradation after 3 days. Alum of 0.1% level retarded the retrogradation, but 0.3% level activated the retrogradation after 24 hours and 0.5% level did after 12 hours. The effect of additives on the retrogradation of rice starch gels showed the different tendencies at the level of additives. On 0.1% level, the effect of those was similar but on 0.5%, the degree of retardation increased in order of oligosaccharide, SE1170, alum, no addition for up to 2 days of storage and SE1170, no addition, oligosaccharide, alum for 3 days of storage.

• Journal of Distribution Research
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• v.10 no.2
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• pp.99-120
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• 2005

First, based on extant studies in the field, the author extracts environments, general and personalized interactions between an internet shopping mall and its customers, interactions among customers, and outcomes as 5 relevant dimensions of the service quality of an internet shopping mal She derives hypotheses on the relationships between each of the service quality dimensions and each of the three components of the relationship quality, satisfaction, trust, and commitment. She also investigates the moderating role of the relationship duration defined by the length of use in the relationships. She studies the relationships among the three relationship quality components and their effects on the future intentions of relationship maintenance, too. Through a survey on college students and adult consumers, she gathers 349 qualified questionnaires. Applying regression methods on the data, she finds out that most of the relationships between each of the service quality dimensions and each of the relationship quality dimensions are statistically significant but that the strengths of relationship are quite different dimension by dimension. The moderating effect of the relationship duration is not found except one case, the relationship between general interactions and trust. The author also finds out positive relationships between satisfaction and trust between satisfaction and commitment, and between trust and commitment. Positive relationships between trust and the future intention of relationship maintenance and between commitment and the future intention are found. But the data does not reveal any statistically significant relationship beetween satisfaction and the future intention. The author provides a few implications of the research results and future research agenda.

• Proceedings of the KSRS Conference
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• v.1
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• pp.34-37
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• 2006

When tsunami waves propagate across open ocean they are steered by Coriolis force and refraction due to gentle gradients in the bathymetry on scales longer than the wavelength. When the wave encounters steep gradients at the edges of continental shelves and at the coast, the wave becomes non-linear and conservation of momentum produces squirts of surface current at the head of submerged canyons and in coastal bays. HF coastal ocean radar is well-conditioned to observe the current bursts at the edge of the continental shelf and give a warning of 40 minutes to 2 hours when the shelf is 50-200km wide. The period of tsunami waves is invariant over changes in bathymetry and is in the range 2-30 minutes. Wavelengths for tsunamis (in 500-3000 m depth) are in the range 8.5 to over 200 km and on a shelf where the depth is about 50 m (as in the Great Barrier Reef) the wavelengths are in the range 2.5 - 30 km. It is shown that the phased array HF ocean surface radar being deployed in the Great Barrier Reef (GBR) and operating in a routine way for mapping surface currents, can resolve surface current squirts from tsunamis in the wave period range 20-30 minutes and in the wavelength range greater than about 6 km. There is a trade-off between resolution of surface current speed and time resolution. If the radar is actively managed with automatic intervention during a tsunami alert period (triggered from the global seismic network) then it is estimated that the time resolution of the GBR radar may be reduced to about 2 minutes, which corresponds to a capability to detect tsunamis at the shelf edge in the period range 5-30 minutes. It is estimated that the lower limit of squirt velocity detection at the shelf edge would correspond to a tsunami with water elevation of less than 5 cm in the open ocean. This means that the GBR HF radar is well-conditioned for use as a monitor of small and medium scale tsunamis, and has the potential to contribute to the understanding of tsunami genesis research.

• Food Science and Preservation
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• v.15 no.2
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• pp.191-196
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• 2008

We examined the effects of four different types of cutting on the quality characteristics of sweet pumpkin. Two hundred grams of each of four samples were packed individually in polypropylene mm and stored at $10^{\circ}C$ for 9 days. Samples were evaluated for weight loss, change in hardness, color change, pH change, water-soluble materials, gas changes, and sensory evaluation. $CO_2$concentration increased during storage, whereas $O_2$ concentration rapidly decreased and then stabilized after 3 days. $C_2H_4$ was detected only after 3 days of storage, and steadily increased thereafter. The rate of weight loss steadily increased Analysis of Lab color space indicated no significant change in the L and b values, but an increase in the a value at the end of storage. Waster-soluble solids increased, but hardness showed no change. All the samples underwent a steady increase in pH. Samples cut into 8 pieces had the highest sensory scores.