• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.6
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• pp.449-469
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• 2011

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering during 2010. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of general thermal and fluid flow, fluid machinery, and new and renewable energy. Various topics were presented in the field of general thermal and fluid flow. Research issues mainly focused on the thermal reliability of axial fan and compressor in the field of fluid machinery. Studies on the design of ground source heat pump systems and solar chemical reactors were executed in the field of new and renewable energy. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (3) Refrigeration systems with alternative refrigerants such as hydrocarbons, mixed refrigerants, and CO2 were studied. Performance improvement of refrigeration systems are tried applying various ideas of refrigerant subcooling, dual evaporator with hot gas bypass control and feedforward control. The hybrid solar systems combining the solar collection devices with absorption chillers or compression heat pumps are simulated and studied experimentally as well to improve the understanding and the feasibility for actual applications. (4) Research trend in the field of mechanical building facilities has been found to be mainly focused on field applications rather than performance improvements. Various studies on heating and cooling systems, HVAC facilities, indoor air environments and energy resources were carried to improve the maintenance and management of building service equipments. In the field of heating and cooling systems, papers on a transformer cooling system, a combined heat and power, a slab thermal storage and a heat pump were reported. In the field of HVAC facilities, papers on a cooling load, an ondol and a drying were presented. Also, studies on HVAC systems using unutilized indoor air environments and energy resources such as air curtains, bioviolence, cleanrooms, ventilation, district heating, landfill gas were studied. (5) In the field of architectural environment and energy, studies of various purposes were conducted such as indoor environment, building energy, renewable energy and green building. In particular, renewable energy and building energy-related researches have mainly been studied reflecting the global interest. In addition, many researches which related the domestic green building certification of school building were performed to improve the indoor environment of school.

• Journal of dental hygiene science
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• v.6 no.4
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• pp.277-284
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• 2006

The purpose of this study was to examine the perception of dental hygiene freshmen about their major and their occupational consciousness. The subjects in this study were 361 dental hygiene freshmen at three different colleges in Gyeonggi province. After a survey was conducted, the collected data were analyzed with SPSS WIN 11.5 program. The findings of the study were as follows: 1. As for their view of occupation, the students made a well-paying job a priority(M = 2.97), and looked upon an occupation as a means of living(M = 1.60). Regarding the use of the profits of dental hospitals and clinics, they believed that they should reinvest their profits in a purchase of machinery, an expansion of facilities or technical development(M = 2.00). 2. Concerning relations between their motivation of college entrance and their satisfaction with their major, 96.6 percent of those who found their major satisfactory or quite satisfactory considered it to right up with their alley. 82.6 percent of them chose their major to get a stable job, and 62.8 percent of them did it through the advice of their families, relatives or regular teachers. 59.1 percent of them did it in consideration of their college entrance examination scores. Every student who were pressed for economic reasons to choose their major were unsatisfied with it. Thus, their motivation of college entrance made a statistically significantly wide difference to their satisfaction with major(p < 0.01). 3. They got a mean of 3.10 in occupational consciousness. By sub- category, they scored highest in interpersonal and work ethics(3.19 respectively). They got a mean of 3.04 in academic ethics, and got a mean of 2.99 in professional ethics, which was the lowest mark. 4. As to connections between their general characteristics and occupational consciousness, their occupational awareness was significantly different according to their motivation of college entrance and information they acquired at the time of college entrance(p < 0.05). In regard to the relationship of their satisfaction with major to their occupational awareness, their occupational consciousness statistically significantly varied with their department, their willingness of staying as a dental hygienist, the future prospect of dental hygienist (p < 0.01).

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.7
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• pp.1017-1024
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• 2011

Korean wheat semolina (FS: fine semolina) with similar characteristics to durum wheat semolina was substituted at rates of 0, 10, 20, 30, 40, and 50% in pasta dough and the physical and cooking characteristics were investigated for making optimal pasta. Water absorption of the dough increased with the 10, 20, and 30% substitution ratio of FS. Development times were high with >30% substituted FS. This result positively influenced an increase in production and the preparation of the fresh noodle pasta. Furthermore, soft textured fresh noodles could be made due to the decrease in stability and increased weakness of the >30% substituted FS. The amylograph gelatinization characteristics of Korean wheat semolina exhibited an increase of gelatinization temperature and decrease of maximum viscosity when compared with durum wheat. The handling property of the dough showed more than 4 points in all sample groups. Weight and volume decreased and turbidity and cooking loss increased according to the increasing amount of substituted FS. However, samples with ${\leq}$ 30% FS substitution ratio had similar volumes and cooking losses when compared to the control. The L- and a-values increased and the b-value of color decreased as more FS was added. In a texture analysis, the hardness of the cooking noodles showed a low value with the >30% substituted FS. Springiness, gumminess, and chewiness exhibited a high value. In the results of a sensory evaluation, overall acceptability was high score with more than 7 points for the 30% added FS. The preferences for pasta colors were divided into white, which is similar to the Korean traditional noodle, and yellow, which is similar to durum wheat. Flavor and taste were not affected by substituting with FS. Low hardness and high chewiness was the most preferred noodle. These results suggest that >30% substituted FS was suitable for increasing quality and organoleptic qualities of Korean wheat pasta.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.1
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• pp.21-33
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• 2013

The purpose of this study is to find applicabilities of human bioclimatic maps, using human thermal sensation(comfort) in summer, with microclimatic in situ data and computer simulation results at the study site of downtown Daegu. This includes the central business district(CBD) area and two urban parks, the Debt Redemption Movement Memorial Park and the 2.28 Park, for urban and landscape planning and design. Climatic data and urban setting information for the analysis of human thermal sensation were obtained from in situ measurement and the geographic information system data. As a result, the CBD had higher air temperature than the parks when the wind speed was low. Relative humidities were opposite to the air temperature. Especially, same directional streets with local wind direction had lower air temperature than streets perpendicular to the wind direction. The most important climatic variable of human thermal sensation in summer was direct beam solar radiation. Also, creating shadow areas would be the most relevant method for modifying hot thermal environments in urban areas. The most effective method of creating shadow patterns was making a tree shadow over a pergola, and the second best one was making a tree shadow on the front of north directional building walls. Moreover, how to plant trees for creating shadow patterns was important as well as what kind of trees should be planted. The results of human thermal sensation were warm to very hot at sunny areas and neutral to warm at shaded ones. At the sunny areas, wide, squared shape areas had a little bit higher thermal sensation than those of narrow streets. The albedo change of building walls 0.15 and ground surface 0.1 could change 1/6 of a sensation level at the shaded areas and 1/3 at the sunny ones. These microclimatic approaches will be useful to find appropriate methods for modifying thermal environments in urban areas.

• Journal of agricultural medicine and community health
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• v.27 no.2
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• pp.107-126
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• 2002

Health sub-centers(HSCs) have played an important role in primary health care in rural area in Korea. The unification of neighboring HSCs was a strategy to improve the role of HSCs. This study was conducted to reveal the efficacy of the unified HSC established in Yangbuk-myeon, Gyeongju-si in1997. The utilization patterns of HSC and its related factors, and satisfaction of consumer on HSC were compared before and after unification of two HSCs in Gampo-eup, Yangnam-myeon using questionnaire survey, and also the statistics of medical care services and public health services were compared. Four hundred forty nine subjects were questioned in survey, 156 from Gampo-eup, 147 from Yangbuk-myeon, and 146 from Yangnam-myeon. Following unification, the utilization rates and the frequency of visits in Gampo-eup declined. In all three areas, chronic illness was the common factor influencing the utilization and change in frequency of visits to the unified HSC. Following unification, aspects of consumer satisfaction, for example; accessibility and affordability decreased in Gampo-eup, but increased in both Yangbuk-myeon and Yangnam-myeon. The statistics relating to medical care, X-ray examination, home visiting service, vaccination, and health education showed an increase for the unified HSC when compared to the sum of the statistics for the previous two. The execution rates for other public health services were the same, or a little decreased. Clinical laboratory examinations and the issuing of civil affair documents were new services offered by the unified HSC. It is concluded, the overall consumer satisfaction with the unified HSC was improved. In Gampo-eup, where after unification there was no HSC, it seemed to be a barrier to accessing the unified HSC. The effect of the unified HSC, in the respect of medical care and public health services, was not as significant as expected at the time of being established. Therefore, the strategies to reenforce the unified HSC should be developed to provide all residents with comprehensive primary health care services.

• The Korean Journal of Elementary Counseling
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• v.8 no.1
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• pp.33-50
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• 2009

The purpose of this study was to develop a PBL-based career education program and to examine its effectiveness on school children's career maturity. It's specifically meant to prepare a career education program to assist students to get an accurate grip on their aptitude, interest and personality and explore various sorts of occupations in the course of solving authentic and contextual career-related problems. After children's developmental characteristics and needs were analyzed, task analysis was implemented, and the objectives were defined. And then the core of the program, PBL problems were developed, and the validity of the problems were verified Evaluation plans and tools were prepared to assess children's problem-solving process and presentation, and an online learning space was designed. The program that consisted of 10-minute 21 sessions was provided to fifth-grade elementary schoolers for eight weeks. The findings of the study were as follows: The experimental group that participated in the PBL-based career education program showed a more significant improvement than the control group that didn't in career attitude and three career attitude subfactors involving planness, disposition and compromise. And the former made a more significant progress than the latter in career ability and its subfactors including vocational comprehension, self-understanding and decision-making skills as well. As a result of making a content analysis to make up for the survey, the students reported that they were able to get an objective understanding of themselves and acquire diverse and profound knowledge on work and the business world in the middle of solving the given PBL problems related to different areas in group and giving a presentation. In conclusion, a PBL based career education program developed by this researcher encouraged the students to have an objective self-understanding, to have a dynamic interactive discussion with their group members. Therefore the program had a positive impact on boosting the career attitude and career ability of the elementary schoolers. The findings suggested that in the field of elementary career education, autonomous learning attitude and subjecthood are the crucial factors to stimulate school children to explore and create their own future.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.5 no.1
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• pp.45-67
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• 2010

On July 21st in 2005, People's Bank of China (PBOC) turned the currency peg against the U.S. dollar into managed currency system based on a basket of unnamed currencies under China's exchanged rate regime. This change means that China's enterprises are not free from currency fluctuations. The purpose of this study is to analyze the relations between Renminbi fluctuations in the floating exchange rate and financial results of venture companies. The process and outcomes of this study are as follows, First, in order to measure the financial results of venture companies, I choose venture companies in Shandong Province listed on the Shanghai Stock Exchange (SSE) at random and several quarter financial sheets according to safety ratios, profitability ratios, growth ratios, activity ratios. Second, I arrange the daily Renminbi exchange rate data announced from July 21st, 2005 to December 31st, 2008 by PBOC into the quarterly data. Third, in order to confirm the relations between Renminbi fluctuations and financial results of venture companies, I carry out Pearson's correlation analysis. As a result, the revaluation of the Chinese Renminbi has weakly negative effects on debt ratio, total assets turnover ratio and equity turnover ratio in statistics. But the revaluation of the Chinese Renminbi is not related to other financial index in statistics. The result of this study is that the revaluation of the Chinese Renminbi has little influence on the export and import of Chinese venture companies and certifies the fact that Chinese venture companies have much foreign currency assets. In addition to avoid the currency exposure risk, this study shows the effective method about currency exposure risk which adjusts proportion of Renminbi to foreign currency.

• The Korean Journal of Food And Nutrition
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• v.29 no.4
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• pp.465-473
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• 2016

This study was conducted in order to investigate the antioxidant capabilities and quality characteristics of instant porridge made of foxtail millet (Setaria italica Beauv.) from different varieties with different endosperm characteristics and processing using different methods. The two foxtail millet varieties used in this study were waxy foxtail millet, 'Samdachal', and non-waxy foxtail millet, 'Samdame'. The means of processing food to create instant porridge were dry cereal frying, wet cereal frying, freeze drying after steaming, popping, and no treatment. The WAI (water absorption index) of instant porridge made of waxy foxtail millet was higher than that of non-waxy foxtail millet, and popping created the highest WAI among the treatments tested. Whean we analyzed RVA characteristics of non-waxy foxtail millet instant porridge, peak viscosity and setback values were decreased in all processed foxtail millet instant porridge compared to non-waxy foxtail millet instant porridge. In waxy foxtail instant porridge, the peak and final viscosities of processed treated instant porridge increased. The viscosity just after pouring hot water into the instant porridge was higher in waxy foxtail millet porridge treated by freeze drying after steaming, popping, and wet cereal frying; the viscosity of non-waxy foxtail porridge was increased after popping as compared with the other treatments. The polyphenol contents and antioxidant activities were increased in all processed, treated-instant porridge except for freeze dried porridge after steamingnt. The popping treatment showed the highest polyphenol contents (1.5 fold), and ABTS antioxidant activity (1.2 fold), compared to no treatment. Non-waxy foxtail millet porridge produced by popping earned the highest sensory evaluation scores.

• Journal of the Korean earth science society
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• v.33 no.4
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• pp.360-375
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• 2012

The purpose of this study was to compare 10th grade students' understanding of concepts about the plates' motions depending on the different spatial ability. Based on previous studies and literature reviews, two instruments were selected and used in this study. The Spatial Perception Test developed in Korean Testing Center was applied to measure students' spatial ability. Another instrument for testing students' understandings of plates' motions consists of a total of 10 items. The instruments were distributed to 118 students who were 10th graders in metropolitan city. The results are as follows: First, a correlation coefficient between conceptual understanding of plates' motions and spatial ability was r=0.439 (p<.01). It indicates that conceptual plates' motions and spatial ability have a moderate relationship. The students were divided into two groups (high and low) by spatial ability. The independent t-test was performed and reveals that the statistically significant difference between high and low groups. On the other hand, the 6 students (3 higher spatial ability students and 3 lowers) were selected and interviewed individually to find the differences in their understanding of the concept of plates' motions. The findings from interviews indicate that most students recognized about concepts of trench and ocean ridge, a rise and drop of the mantle, and divergent and convergent boundaries. However, students had misconceptions about section of trench and ocean ridge. In addition, the students who had higher spatial ability knew the more proper concepts about the creation and extinction of plate, crustal movements, and bottom of the ocean extension, whereas the students who had the lower spatial ability had misconceptions.

• 대한공업교육학회지
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• v.38 no.2
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• pp.114-135
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• 2013

The purpose of this study is to provide base line data for right concept and identity establishment of Specialized Vocational high school, to identify recognition of Specialized Vocational high school, to analyze image of Specialized Vocational high school recognized by middle school student. The population was all middle school third year students in Korea. Using random sampling technique, 50 classes of 61 schools were sampled for the study. A survey questionnaire used Semantic Differential(SD) suggested by Osgood(1957). SD consisted of a number of adjective pairs, finally, this study used 11 adjective pairs to have validity. 1,198 out of 1,441 questionnaire were returned (a return rate of 83.14%), among which 935 were used for the analysis after data cleaning. An alpha level of 0.05 was established a prior for determining significance. All data analysis was accomplished using the SPSS 20.0 Win. Based on the finding of the study, the major results of the this study were as follows : 1. Higher average is female students' image of Specialized Vocational high school than male students' that, but, The difference between the two samples was not statistically significant. 2. It was only 20% that receive career education of Vocational high school. It is necessary to accomplish and expand career education of Specialized Vocational high school for proper career education from middle school, to realize career exploration and decide one's career path based on one's specialty. 3. They have positive images who hope for going on to the Specialized Vocational high school of education than the others. 4. It is necessary to accomplish and expand career education of Specialized Vocational high school for proper career education from middle school, to realize career exploration and decide one's career path based on one's specialty, because the result was statistically significant. 5. They have the more possitive image of Specialized Vocational high school, the more know it, totally.