• Current Photovoltaic Research
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• v.2 no.4
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• pp.168-172
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• 2014

Under concentrated illuminations, the solar cells show higher efficiencies mainly due to an increase of the open circuit voltage. In this study, InGaP/InGaAs/Ge triple-junction solar cells have been grown by a low pressure metalorganic chemical vapor deposition. Photovoltaic characteristics of the fabricated solar cells are investigated with a class A solar simulator under concentrated illuminations from 1 to 100 suns. Ideally, the open circuit voltage should increase with the current level when maintained at the same temperature. However, the fabricated solar cells show degraded open circuit voltages under high concentrations around 100 suns. This means that the heat sink design is not optimized to keep the cell temperature at $25^{\circ}C$. To demonstrate the thermal degradation, changes of the device performance are investigated with different bonding conditions and heat sink materials.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.5
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• pp.393-401
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• 2000

To define the postnatal changes in ANP secretion in response to mechanical stretch and atrial compliance, experiments have been done in perfused nonbeating rabbit atria with different ages: 1-day, 1-, 2-, 3-, 4-, and 8-wk-old. In 1-day-old-rabbits, an increase in intraatrial pressure resulted in an increase in atrial volume, which was higher than that in 1-wk-old rabbits. Increases in atrial volume stimulated the secretion of ANP with concomitant translocation of extracellular fluid (ECF) into the atrial lumen. However, mechanically stimulated ECF translocation was lower in 1-day-old rabbits than that in 1-wk-old rabbits. Therefore, positive relationship between mechanically stimulated ECF translocation and ANP secretion was shifted upward in 1-day-old rabbits, as compared to 1-wk-old rabbits. Changes in atrial volume and ECF translocation were gradually increased with aging and reached the peak value at 4 wk. The stretch-induced ANP secretion in terms of ECF translocation (the interstitial ANP concentration) was also increased with aging and reached the peak value at 4 wk. The interstitial ANP concentration was dependent on the atrial content of ANP. These data suggest that the higher level of atrial ANP secretion is related to the postnatal changes in atrial volume and unidentified factor.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.6
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• pp.49-57
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• 2015

This paper presents the discharge characteristics and economic feasibility of a Dry $Air/O_2$ and a $N_2/O_2$ mixture gas in order to review $SF_6$ alternative. From AC discharge experiment in an quasi-uniform field, it was found that the optimal $N_2/O_2$ mixing ratio which breakdown voltage and surface flashover voltage were the highest was 70/30 and that the pressure dependence on the breakdown voltage was higher than that of the surface flashover voltage in the Dry $Air/O_2$ and the $N_2/O_2$ mixture gas. The mixing ratio (70/30) and the tendency of the pressure dependence were described in detail based on physical factors (impact ionization coefficient, electron attachment coefficient, secondary electron emission coefficient) involved in discharge mechanism and a electron source, respectively. In addition, the performance insulation and the economic feasibility of the Dry $Air/O_2$ and the $N_2/O_2$ mixture gas were discussed so that Dry $Air/O_2$ mixture gaswas more suitable than $N_2/O_2$ mixture gas to the $SF_6$ alternative.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.10
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• pp.86-92
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• 2013

In studies on an alternative insulating gas of $SF_6$ gas, the section of the alternative gas and an insulation technique to improve its low dielectric strength have been reported, but very few attempts have been made at the dependence of a gas pressure and a gap as well as the medium effect in the alternative gas. The purpose of this paper is to analyze the dependence of the gas pressure and the gap at surface flashover voltage in dry air. The dependence is analyzed based on the medium effect. The medium effect by the gas pressure and the gap can be explained by surface roughness of a solid dielectric and an electrode as well as an electric field which decreases due to the correlation between the collision ionization coefficient and the gap, respectively. In addition, an insulation technique which can fabricate a compact eco-friendly gas insulated switchgear is proposed by the results of this paper.

• Journal of the Korean Institute of Landscape Architecture
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• v.18 no.4
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• pp.127-140
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• 1991

The Primary purpose of this study is to investigate factors and variables which have significant effects on user satisfaction with recreational facilities in Taejong-Dae recreational complex, thereby establishing indices of planning and development of urban parks and open space. To test the causal models of this research, the date were gathered by self-administered questionnaires from 967 households in Pusan City which were selected by the multi-stage probability sampling methood. The analysis of the multi-stage primarily consists of two phase : The first analysis dealt exploratory factor analysis which identified major factors involved in satisfaction with recreational activities and facilities in Taejong-Dae recreational complex and the second analysis tested the fit of the causal models of this research by employing LISREL methodology. There are three advantages of using LISREL over other multivariate analysis methods : First, measurement error is allowed and calculated in LISREL, otherwise there is a risk of seriously misleading estimates of coefficients ; Second, LISREL deals with latent variables or unmeasured variables ; Third, it enables to test causal relations among variables. The factors analysis identified that five factors are involved in satisfaction with recreational facilities. The five factors of satisfaction with recreational facilities are space for repose and relaxation, active recreation facilities such as pool and zoo, physical exercise facility, convenience and maintenance facility, and linear facility, and linear facility for walking. The second phase analysis tested the fit of the causal models for satisfaction with recreational facilities to the data and identified statistically significant causal linkage among overall satisfaction with Taejong-Dae recreational complex, other endogenous factors and exogenous variables. Overall fits of both causal models were very good. Among endogenous factors, facility for repose and relaxation. linear facility for walking, active recreation facility, facility for convenience and maintenance were identified as having significant effects on overall satisfaction. Exogenous variables which have significant effects on endogenous variables wer also identified. These significant relationships indicate important factors and variables that should be considered in planning and development of the recreational complex. On the basis of these significant causal relationships, implications for planning and the delovepment of Taejong-Dae recreational complex were suggested.

• Journal of Veterinary Clinics
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• v.31 no.4
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• pp.322-324
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• 2014

Candidiasis caused by Candida albicans is a localized mucocutaneous disease. It occurs worldwide in various kinds of animals. A 7-year-old male spotted seal weighing 98 kg showed facial skin lesions. The present case was characterized by erythematous, thickened, and alopecic skin lesions in the periocular region and on the commissure of the lower lip. For diagnosis, skin scraping and culture of samples from the facial skin lesions were done. Colonies were cream-colored and glistening after 3 days of culture on Sabouraud dextrose agar. Typical yeast-like cells were observed by microscopic inspection after Gram staining. Recovery was achieved with itraconazole (1 mg/kg SID) for 7 days, repeated three times at 2-week intervals.

• Korean Journal of Veterinary Service
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• v.40 no.1
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• pp.7-14
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• 2017

The present study was undertaken to clarify the changes in hematological values of Korean indigenous goats according to age. Blood samples were collected from 16 goats (5 females and 11 males) from birth up to the age of 6 weeks and the levels of various hematological values were analyzed. The body weight was increased from 2.54 kg at birth to 6.41 kg at 6 weeks age. The erythrocytes (RBC) counts and hemoglobin (Hb) values of goats were decreased at 2 weeks after birth, and increased gradually from 4 weeks after birth. The hematocrit (Ht) values were decreased until 4 weeks after birth, and increased at 6 weeks after birth. The mean cell volume (MCV) and mean cell hemoglobin (MCH) were decreased until 6 weeks after birth. The mean cell hemoglobin concentration (MCHC) was increased slightly from 2 weeks after birth. The red cell distribution width (RDW) was increased significantly at 2 weeks after birth, and decreased from 4 weeks after birth. The platelet (PLT) counts were increased significantly from 2 weeks after birth. The mean platelet volume (MPV) was decreased at 2 weeks after birth, and increased gradually from 4 weeks after birth. The total white blood cell (WBC) counts and the mean absolute numbers of neutrophil, lymphocyte, monocyte and eosinophil were increased from 2 weeks after birth. In conclusion, the data obtained from this study may be valuable as a standard for interpreting results of hematological analyses in Korean indigenous goats.

• Korean Journal of Microbiology
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• v.48 no.2
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• pp.102-108
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• 2012

Fecal specimens from acute gastroenteritis in Seoul from 2003 to 2007 were collected and then tested for the presence of Norovirus by RT-PCR. Among a total of 4,685 samples investigated, 383 samples (8.2%) were positive. The analysis of outbreaks related norovirus contamination occurred from 2003 to 2007 in Seoul revealed 57 cases happened during investigated period. Seasonal prevalence showed winter season predominant characteristics of pattern of epidemics by long term investigation for norovirus infections. The incidence of norovirus infection in the case of acute gastroenteritis by catering food in school were 32%, by food in general restaurant were 29%. This epidemiological investigation in Seoul was strongly needed for control and prevention of outbreaks related with norovirus by forecasting disease epidemics.

• Journal of Digital Convergence
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• v.11 no.4
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• pp.57-69
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• 2013

Progresses in ICT make the processing and exchange of personal data across international borders often necessary and relatively easy. The challenge lies in protecting fundamental rights and freedoms of individuals, notably the right to privacy and the right to personal information, while encouraging the free and secure flow of information across borders for the continued expansion of online transactions. The key to establishing a functioning international solution for personal data protection is to strike a right balance between the two camps which currently dominate the debate - the advocates of individual privacy rights on one side exemplified by the EU, and the proponents of self-regulation and economic efficiency on the other, represented by the U.S. In the face of a growing tension between the two sides each equipped with their own ideals, a practical solution may lie in utilizing established institutions of standardization such as ISO and IEC as a ground upon which an agreement can take its root.

• KIEAE Journal
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• v.16 no.3
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• pp.83-88
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• 2016

Purpose : This study aimed to verify the surface hardness and water repellency of earth paint manufactured with earth, a natural material, and provide the results as basic data for paint made with natural materials. Method : After presenting the accurate manufacturing methods for basic materials for paint, the authors conducted and analyzed experiments to evaluate surface hardness and water repellency, fundamental performance indicators for paint, based on different mixture ratios. From the results of the experiment to assess the surface hardness of flour-based earth paint, we observed high surface hardness only after painting the specimen three times. Since potato starch-based earth paint has higher viscosity than its flour-based counterpart, the former did not paint well on the first occasion, resulting in low surface hardness. After painting two or more times, however, it was observed to have higher surface hardness than flour-based earth paint. Result : It was found that at least three iterations of painting was required to obtain high surface hardness of potato starch-based earth paint. Furthermore, the results of the water resistance experiment of earth paint suggest that the use of environment-friendly finishing materials coupled with boiled linseed oil will mitigate the drawbacks of earth paint. The experiment with one-year-old specimens also demonstrated similar water repellent characteristics, which indicates that the performance will improve once the paint has dried for a sufficient period of time.