• Journal of Korean Society for Atmospheric Environment
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• v.9 no.2
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• pp.147-153
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• 1993

From March 1990 to August 1991, every each 5mm bulk precipitation samples were collected at one residental area in Taejon City to investigate chemical characteristics of acid rain. Major ion concentrations of rain samples $(pH, SO_4^{2-}, NO_3^-, CL^-, NH_4^+, Na^+, K^+, Ca^{2+}, Mg^{2+})$ were analysed and compared with the concentration of air pollutants (T. S. P, $SO_2, NO_x$) that were measured by Ministry of Environment. The results of statistical analysis are as followings. Rain pH was relatively high on October and January and relatively low on August, November and February. Major anion is sulfate, and it's concentration is 2.36 times higher than nitrate's, and major cations are ammonium, sodium and calcium ion. Monthly variation of sulfate and calcium concentrations are higher than the others. Ion concentration and rain pH were correlated negatively with rainfall amount. Major ions in rain samples were $SO_4^{2-}, NO_3^-, NH_4^+, Ca^{2+}$ and regression equations are proposed by multiple regression of measured data. Also, regression equation between air pollutants(T. S. P, $SO_2$) and $SO_4^{2-}, Na^+, K^+, Ca^{2+}, Mg^{2+} ions in rain samples were made. From this wer can predict rain pH.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.10
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• pp.130-136
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• 2008

The purpose of this study was to investigate chaotic characteristics of major joint motions during treadmill walking. Gait experiments were carried out for 20 healthy young women. The subjects were asked to walk on a treadmill at their own natural speeds. The chaos analysis was used to quantify nonlinear motions of eleven major joints of each woman. The joints analyzed included the neck and the right and left shoulders, elbows, hips, knees and ankles. The recorded gait patterns were digitized and then coordinated by motion analysis software. Lyapunov exponent for every joint was calculated to evaluate joint characteristics from a state space created by time series and its embedding dimension. This study shows that differences in joint motion were statistically significant.

• Journal of Korean society of Dental Hygiene
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• v.16 no.4
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• pp.549-557
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• 2016

Objectives: The purpose of the study is to investigate the influence of education service quality on major satisfaction in the dental hygiene students. Methods: A self-reported questionnaire was completed by 271 dental hygiene students in Seoul from April 1 to 20, 2016. The questionnaire consisted of general characteristics of the subjects(6 items), education service quality (27 items), and major satisfaction of students(23 items). The instrument for education service quality was adapted from Parasuraman and modified by Park & Lee. Likert 5 point scale adaptation included physical environment, reliability, responsiveness, certainty, empathy, class professors, administrative facilities, and school activities accessibility. Cronbach's alpha test in the study was 0.956 in education service quality and 0.951 in major satisfaction. Results: The education service quality was 3.1 points. The lower grade students tended to have the higher education service quality (p<0.001). The satisfaction to class professors was 3.2 points. The education service quality had a significant positive relation to major satisfaction. The satisfaction was positively influenced by physical environment, responsiveness, certainty, and empathy. Conclusions: A positive motivation to education service quality leads to major satisfaction. A variety of strategies are very important to enhance the education specialization.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.761-762
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• 2006

A number of techniques have been developed for estimation of speed or position in motor drives. The accuracy of these techniques is affected by the variation of motor parameters such as the stator resistance, stator inductance or torque constant. This paper is proposed a neural network based estimator for torque and stator resistance in IPMSM Drives. The neural weights are initially chosen randomly and a model reference algorithm adjusts those weights to give the optimum estimations. The neural network estimator is able to track the varying parameters quite accurately at different speeds with consistent performance. The neural network parameter estimator has been applied to slot and flux linkage torque ripple minimization of the IPMSM. The validity of the proposed parameter estimator is confirmed by the operating characteristics controlled by neural networks control.

• The Journal of Korean Academic Society of Nursing Education
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• v.12 no.2
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• pp.170-177
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• 2006

Purpose: This study was performed to identify the relationship between self-esteem and satisfaction in major of nursing students. Methods: Data were collected from the 10th to the 14th of April in 2006, from 281 nursing students in Jeollabuk-Do area. The collected data were analysed by using the SPSS WIN 11.0. Results: The results of this study were as followings: 1) The mean score for self-esteem was $2.89({\pm}.42)$, self-esteem was significantly different according to the general characteristics of grade(F=4.718, p=.010), satisfaction of pocket money(F=11.241, p=.000), satisfaction of present life(F=9.875, p=. 000) and hope for the employment field(F=2.583, p=.026). 2) The mean score for satisfaction in major was $3.79({\pm}.49)$, satisfaction in major was significantly different according to the general characteristics of satisfaction of pocket money(F=5.280, p=.006), motivation of entrance(F=7.384, p=.000), satisfaction of present life(F=27.000, p=.000), hope for the employment field(F=3.019, p=.011) and one of family (t=2.416, p=.017). 3) There was a significant correlation between self-esteem and satisfaction in major(r=.353, p=.000). 4) The most important variables affected satisfaction in major could explain a total 27.9%, were accounted for 22.7% in the satisfaction of present life and 5.2% in the self-esteem by the stepwise multiple regression analysis. Conclusion: As a result, self-esteem was correlated with satisfaction in major in nursing students. Therefore we need to develop various self-esteem program for nursing students.

• Journal of Korean Society of Forest Science
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• v.96 no.2
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• pp.197-202
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• 2007

This study is conducted to investigate the factors affecting lumber conversion rate of sawmill industry in South Korea. Data were obtained from the survey of 38 sawmills in all geographic regions of South Korea. The variables examined in this study were region, softwood/hardwood log, domestic/imported/both log, the number of power-driven carriages (PDC) installed, the year when and country where PDCs was manufactured, the horse power of PDC, the number of labors required to operate each PDC, the sawing capacity of mill (mill size), and the types of major product and by-products. The lumber recovery factor (LRF) of sawmills were significantly influenced by the origin of logs, level of PDC automation, sawmill size, and size of logs (measured in diameter and length) while not by the location of the mill, types of major product and by-product, log species, and characteristics of PDC. Although these results provide useful information for understanding the technological characteristics of the Korean sawmill industry, further investigation with larger sample is necessary to reveal the more reliable characteristics of sawmill industry in South Korea.

• Proceedings of the Korea Society of Costume Conference
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• 2003.10a
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• pp.68-68
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• 2003

Recently, street fashion has been regularly introduced in many fashion media because both consumers and marketers began to recognize the importance of street fashion as a meaningful and objective fashion information source. As the globalization proceeds in fashion field,' the street fashion informations in major cities which has led world fashion trends become more influential on domestic fashion, but little concern has been paid on it. This study classified women's street fashion in 4 major world fashion cities such as Paris, London, New York, Tokyo and identified style characteristics of each group. For data collection, 795 front-view photos were selected from the two fashion trade publication 'STREET' and 'VIEW' which has introduced street fashion photos in those cities from 1996. Classification process went on three stages: sorting, naming and grouping. 49 undergraduate students were divided into 12 teams and about 80 photos were given to each team to sort into several sub-groups by overall images or common style characteristics. Then each sub-group was named according to common images or characteristics. Final groups came out after grouping each sub-group with a similar or same title together. For each group, common style characteristics were analyzed.

• Journal of the Semiconductor & Display Technology
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• v.8 no.1
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• pp.7-12
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• 2009

The outgassing effects of selected vacuum materials on the vacuum characteristics were simulated by the $VacSim^{Multi}$ simulation tool. This investigation examined the feasibility of reliably simulating the outgassing characteristics of common vacuum chamber materials (aluminum, copper, stainless steel, nickel plated steel, Viton A). The optimum design factors for these vacuum systems were suggested based on the simulation results. The baking-out effects of the modeled systems and materials on the performance of the vacuum system were also analyzed. The simulation predicted that the overall outgassing effect was more significant in the TMP system than in the DP system and that the utilization of a booster pump has a greater effect on the evacuation time than on the ultimate pressure.

• Research in Plant Disease
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• v.24 no.2
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• pp.113-122
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• 2018

Ripe rot, Botrytis storage rot and Sclerotinia rot are major fungal diseases that lead to deterioration of fruit quality in Korea. Ripe rot, which is caused by Botryosphaeria dothidea, affects harvested fruits during post-storage ripening, while Botrytis storage rot, caused by Botrytis cinerea, affects harvested fruits during cold storage, and Sclerotinia rot, caused by Sclerotinia sclerotiorum, mainly affects immature fruits on the trees. Major fungal fruit rots tend to affect yellow- and red-fleshed cultivars of kiwifruit more severely because of the sharp increase in their cultivation acreage in recent years in Korea. In this review, we summarize symptoms and epidemiological characteristics of the major fungal fruit rots and propose integrated management methods of the diseases that can be practically utilized at the farmers' orchards in order to prevent the diseases based on our research works and field experiences and the research works of others conducted during the last three decades worldwide.

• Journal of Korea Port Economic Association
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• v.31 no.4
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• pp.189-207
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• 2015

The purpose of this study is to examine the relationship between the network characteristics of ports and their performance that is represented by port competitiveness for the port operators. The study employs Social Network Analysis (SNA) to evaluate network characteristics comprising four centrality indices. For this research, data from Containerization International Yearbooks for 2006-2011 is used to analyze the service networks of 20 major liner shipping companies. In SNA, nodes (vertices) in the network are the ports and links (edges) in the network are connections realized by vessel movements, such that the liner shipping network determines the port network. In addition, panel regression analysis has been employed to investigate the relationship between port network characteristics and their performance. The results suggest that the four centrality indices identify the roles of the world's major ports from 2006 to 2011 and that port performance is determined not only by macroeconomic variables and service capabilities but also by the eigenvector centrality of ports in networks.