• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.6
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• pp.697-703
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• 2023

As a part of the global industrial efforts to reduce environmental pollution owing to air pollution, regulations have been established by the International Maritime Organization (IMO). The IMO has implemented various regulations such as EEXI, EEDI, and CII to reduce air pollution emissions from ships. They are also promoting measures to decrease the power consumption in ships, aiming to conserve energy. Most of the power used in ships is consumed by electric motors. Among the motors installed on ships, the engine room blower that takes up a significant load, operates at a constant irrespective of demand. Therefore, energy savings can be expected through frequency control. In this study, we demonstrated the efficacy of energy savings by controlling the frequency of the electric motor of the generator blower that supplies combustion air to the generator's turbocharger. The system was modeled based on the output data of the turboharger outlet temperature in response to the blower frequency inpu. A PI control system was established to control the frequency with the target being the turbocharger outlet temperature. By maintaining the turbocharger design standard outlet temperature and controlling the blower frequency, we achieved an annual energy saving of 15,552kW in power consumption. The effectiveness of energy savings through frequency control of blower fans was verified during the summer (April to September) and winter (March to October) periods. Based on this, we achieved annual fuel cost savings of 6,091 thousand won and reduction of 8.5 tons of carbon dioxide, 2.4 kg of SOx, and 7.8 kg of NOx air pollutants on the training ship.

• Journal of Fisheries and Marine Sciences Education
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• v.2 no.1
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• pp.15-28
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• 1989

The aim of this study is to improve the curriculum for the fisheries processing department in fisheries junior college in Korea. For this study, questionaries to alumani and students of the fisheries processing department of Tong-Yeong Fisheries Junior College are made and meeting materials of professors concerned and some leading managers of food processing company. In addition, curricula of the department food processing in two year or four year colleges both domestic and foreign are refered. The results obtained can be shown as follows ; 1. Subjects of the standard laboratory work designated by the Ministry of Education and required at the practical techique examination for the food precessing technitian certificates were chosen to student compulsorily, and the other subjects necessary to acquistion of the techniques were opened in this course electively. 2. The food processing departments in nationwide twenty-three junior college open seventy-eight major subject courses. Among those subjects, we choose the subjects only related to fisheries processing ones to put stress on the features of fisheries processing department. 3. The selected courses in improved curricula of this work are total 119 credits spending 142 class-hour per weeks. Detailed curricula are as follows ; liberal arts are consist of 13 subjects-24 credits, essential major subjects 12 subjects-32 credits, elective subjects 24 subject-56 credits and interdisciplinary subjects 2 subjects-5 credits. 4. The linking system of industrial-educational co-operation have to be established to fulfil the field practice, and legal basis should be made to support these educational circumstances. 5. To make sure a live education in junior college, present education terms should be extended more than 1 year, and improved textbook, method of experiment, practice and evaluation continuously.

• 한국산학경영학회:학술대회논문집
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• 2004.11a
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• pp.55-72
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• 2004

Before 2003 the companies In Korea should capitalize the interest expenses that are attributable to the acquisition, construction or production of a qualifying assets. However, according to the revised standard which should be applied from 2003, the companies can either capitalize the interest expenses or recognize as an expense when they are incurred. Therefore almost all the companies confronted with the decision making of accounting choices on the interest capitalization. This paper empirically examines which financial characteristics of the companies affect the accounting choice by using logistic regression model and reviews the sufficiency of the foot notes disclosures regarding the capitalized interest. The variables of the financial characteristics are change of debt-equity ratio, borrowing ratio, qualifying assets ratio, firm sire and income smoothing. The results of this study are summarized as follows. First, among the financial characteristics, only qualifying asset ratio has the significant difference between capitalized companies and expensing companies. Second, the results of logistic regression indicate that qualifying asset ratio and firm size have the significant influence on the accounting choices. Therefore, I cannot find the evidence supporting that the companies use the accounting choice to manage the financial ratios.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.4 no.4
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• pp.113-125
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• 1984

Water supply has been mainly dependent on the construction of the dams in Korea. It is difficult, however, to continue to construct dams for many reasons, such as the decrease of construction sites, the increase of construction costs, the compensation of residents in flooded areas, and the environmental effects. Water demands have increased and are expected to continue increasing due to the concentration of people in the cities, the rise of the living standard, and rapid industrial growth. It is acutely important to find countermeasures such as development of ground water, desalination, and recycling of waste water to cope with increasing water demands. Recycling waste water includes all means of supplying non-potable water for their respective usages with proper water quality which is not the same quality as potable water. The usages of the recycled water include toilet flushing, air conditioning, car washing, yard watering, road cleaning, park sprinkling, and fire fighting, etc. Raw water for recycling is obtained from drainage water from buildings, toilets, and cooling towers, treated waste water, polluted rivers, ground water, reinfall, etc. The water quantity must be considered as well as its quality in selecting raw water for the recycling. The types of recycling may be classified roughly into closed recycle systems and open recycle systems, which can be further subdivided into individual recycle systems, regional recycle systems and large scale recycle system. The treatment methods of wastewater combine biochemical and physiochemical methods. The former includes activated sludge treatment, bio-disc treatment, and contact aeration treatment, and the latter contains sedimentation, sand filtration, activated carbon adsorption, ozone treatment, chlorination, and membrane filter. The recycling patterns in other countries were investigated and the effects of the recycling were divided into direct and indirect effects. The problems of water reuse in recycle patterns were also studied. The problems include technological, sanitary, and operational problems as well as cost and legislative ones. The duties of installation and administrative organization, structural standards for reuse of water, maintenance and financial disposal were also studied.

• 대한공업교육학회지
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• v.43 no.1
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• pp.1-19
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• 2018

As the BIM designing technology has been applied recently in the construction field, architectural design education in the field of work and university has been changing to 3D modeling. Nevertheless, architectural design & drafting education in the construction specialized vocational high school is not responding appropriately to change. Despite the fact that students need to have 3D modeling design ability, there is a very lack of 3D housing design instructional material that can satisfy the change. The purpose of this study is to develop BIM-based 3D modeling instruction material and apply to analyze effect on interest and task performance ability on Housing Design. The 3D modeling instruction material used in this study was developed through four stages of preparation, development, implementation and evaluation according to the PDIE model procedure. Also, the experimental design model for hypothesis testing was used nonequivalent control group pretest-posttest design. Based on the experimental design model, BIM-based 3D modeling instruction material was performed in the experimental group and 2D CAD-based standard instruction material was taught in the control group. Experimental treatment was conducted on the students of construction specialized vocatinonal high school, and applied to the subject of Professional Drafting in the 12 hours. Before and after the experimental treatment, the interest and task performance ability on Housing Design were tested. Based on the test results, we analyzed the effects of the 3D modeling instruction material through the independent samples t-test. The results of the study are as follows. First, BIM-based 3D modeling instruction material was developed of 'Housing Design & Drafting' unit on the subject of Professional Drafting in construction specialized vocational high school. Second, the application of 3D modeling instruction material has shown to be effective in improving students' interest. Third, the application of 3D modeling instruction material has shown to be effective in improving students' task performance ability on Housing Design.

• Journal of Korean Home Economics Education Association
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• v.29 no.2
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• pp.23-39
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• 2017

The Purpose of this study is to present the basic data for selecting and improving the safety education contents which help practically middle school students through analysis of contents of safety education in 'field of home life' of 2009 revised middle school textbooks. The subjects of analysis are 12 types of middle school textbooks: in total 24 books written by 12 publishers in terms of the revised curriculum in 2009. The analysis criteria is developed by the researcher referring to preceding studies regarding safety education based on the seventh safety education standard presented by the Ministry of Education (2015). With such analysis criteria, all words related to the contents of the safety education of analysis criteria were extracted from each textbook, such as words directly mentioned as 'safety', words mean as 'psychological safety' and 'happy life', words related to 'attention', 'note', 'stability' etc. Under the analytic frame of safety education contents according to a home economics textbook, content analysis method was used for producing the frequency and percent of those words. The textbook analysis shows that the number of pages regarding safety education is 336.3 pages, as 9.8% in total 3,412 pages of 12 types of technology and home economics textbooks. As following the analysis of each textbook volume of the proportion in the contents related to safety education, 224.9 pages are on the first volume and 111.9 pages are on the second volume. As grades increase from year one to year three, the proportion of safety education in home economics textbooks is decreased. The highest number of safety education contents unit is 'Self-management of youth' which includes three parts of safety education. In the case of a unit for emphasizing practice, experience and practical exercise such as 'Life of youth' and 'Practice of eco-living', safety education content in the area of 'life safety' are mostly contained. Safety accidents related to the most student experienced, Household accidents (1.4%) and experiment or practice accidents (0.3%) are presented in a low figure. The contents of universal housing and school violence are duplicated on first and second volume of text. The most presented safety education content in the 12 types of textbooks are proper sexual attitude, dietary problems, family conflict and food choice. The least common contents are dangerous drugs, family welfare, internet addiction and industrial accident compensation insurance. As this study is to analyze 12 textbooks developed in 2009 revision curriculum, it is necessary to compare it with the textbook written by the revised curriculum in 2015 and to clarify the contents system of safety education and to avoid duplication of contents. In addition, it is necessary to develop and distribute a safety education program that can support textbooks.

• Applied Chemistry for Engineering
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• v.24 no.5
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• pp.551-557
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• 2013

In the present study, pristine carbon nanotube (p-CNT) and thiolated carbon naotube (t-CNT) electrodes were investigated to improve their detectabilities for cadmium (Cd) and lead (Pb). In addition, we evaluate which reaction mechanism is used when the electrolyte contains both Cd and Pb metals. Square wave stripping was employed for analyzing the sensitivity for the metals. A frequency of 30 Hz, a deposition potential of -1.2 V vs. Ag/AgCl and a deposition time of 300 s were used as optimal SWSV parameters. t-CNT electrodes show the better sensitivity for both Cd and Pb metals than that of p-CNT electrodes. In case of Cd, sensitivities of p-CNT and t-CNT electrodes were $3.1{\mu}A/{\mu}M$ and $4.6{\mu}A/{\mu}M$, respectively, while the sensitivities for Pb were $6.5{\mu}A/{\mu}M$ (p-CNT) and $9.9{\mu}A/{\mu}M$ (t-CNT), respectively. The better sensitivity of p-CNT electrodes is due to the enhancement in the reaction rate of metal ions that are facilitated by thiol groups attached on the surface of CNT. When sensitivity was measured for the detection of Cd and Pb metals present simultaneously in the electrolyte, Pb indicates better sensitivity than Cd irrespective of electrode types. It is ascribed to the low standard electrode potential of Pb, which then promotes the possibility of oxidation reaction of the Pb metal ions. In turn, the Pb metal ions are deposited on the electrode surface faster than that of Cd metal ions and cover the electrode surface during deposition step, and thus Pb metals that cover the large portion of the surface are more easily stripped than that of Cd metals during stripping step.

• Journal of radiological science and technology
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• v.39 no.4
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• pp.651-660
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• 2016

Due to recent population aging, the number of check-up for senior citizens has increased steadily. According to this trend, the market size of dental X-ray equipment and the number of approval and review for these devices have simultaneously increased. The technical document of medical device is required for approval and review for medical device, and medical device companies needs to have work comprehension and expertise, as the document needs to include the overall contents such as performances, test criteria, etc.. Yet, since most of domestic manufacturers or importers of medical devices are small businesses, it is difficult for them to recruit professional manpower for approval of medical devices, and submission of inaccurate technical documents has increased. These problems lead to delay of the approval process and to difficulties in quick entering into the market. Especially, the Ministry of Food and Drug safety (MFDS) standards of a dental extra-oral X-ray equipment, a dental intra-oral X-ray equipment, an arm-type computed tomography, and a portable X-ray system have been recently enacted or not. this guideline of dental X-ray equipment adjusting revised standards was developed to help relative companies and reviewers. For this study, first, the methods to write technical document have been reviewed with revised international and domestic regulations and system. Second, the domestic and foreign market status of each item has been surveyed and analyzed. Third, the contents of technical documents already approved by MFDS have been analyzed to select the correct example, test items, criteria, and methods. Finally, the guideline has been developed based on international and domestic regulation, through close review of a consultative body composed of academic, industrial, research institute and government experts.

• 대한공업교육학회지
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• v.41 no.2
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• pp.48-68
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• 2016

This study was conducted to identify the NCS-related research trends, Keywords, the Keywords Networks and the extension of the Keywords using the sementic network analysis and to seek for the development plans about NCS. For this, the study searched 345 the papers, with the National Competency Standards or NCS as a key word, among master's theses, dissertations and scholarly journals that RISS provides, and selected a total of 345 papers. Annual frequency analysis of the selected papers was carried out, and Semantic Network Analysis was carried out for 68 key words which can be seen as key terms of the terms shown by the subject. The method of analysis were KrKwic software, UCINET6.0 and NetDraw. The study results were as follows: First, NCS-related research increased gradually after starting in 2002, and has been accomplishing a significant growth since 2014. Second, as a result of analysis of keyword network, 'NCS, development, curriculum, analysis, application, job, university, education,' etc. appeared as priority key words. Third, as a result of sub-cluster analysis of NCS-related research, it was classified into four clusters, which could be seen as a research related to a specific strategy for realization of NCS's purpose, an exploratory research on improvement in core competency and exploration of college students' possibility related to employment using NCS, an operational research for junior college-centered curriculum and reorganization of the specialized subject, and an analysis of demand and perception of a high school-level vocational education curriculum. Fourth, the connection forming process among key words of domestic study results about NCS was expanding in the form of 'job${\rightarrow}$job ability${\rightarrow}$NCS${\rightarrow}$education${\rightarrow}$process, curriculum${\rightarrow}$development, university${\rightarrow}$analysis, utilization${\rightarrow}$qualification, application, improvement${\rightarrow}$plan, operation, industry${\rightarrow}$design${\rightarrow}$evaluation.'

• Journal of Food Hygiene and Safety
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• v.29 no.1
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• pp.60-66
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• 2014

This test was performed to evaluate the bactericidal efficacy of a fumigation disinfectant containing 20% ortho-phenylphenol against Pseudomonas aeruginosa (P. aeruginosa) and Enterococcus hirae (E. hirae). In preliminary tests, P. aeruginosa and E. hirae working culture suspension number (N value) were $2.8{\times}10^8$ and $4.0{\times}10^8CFU/mL$, respectively. And all the colony numbers on the carriers exposed to the fumigant (n1, n2, n3) were higher than 0.5N1 (the number of bacterial test suspentions by pour plate method), 0.5N2 (the number of bacterial test suspentions by filter membrane method) and 0.5N1, respectively. In addition, the mean number of P. aeruginosa and E. hirae recovered on the control-carriers (T value) was $2.8{\times}10^8$ and $3.4{\times}10^6CFU/mL$, respectively. In the bactericidal effect of the fumigant, the reduction number of $2.8{\times}10^8$ (d value) was 6.46 and 5.19 logCFU/mL, respectively. According to the French standard for the fumigant, the d value for the effective bactericidal fumigant should be over than 5 logCFU/mL. With the results from this study, the fumigation disinfectant containing 20% ortho-phenylphenol has an effective bactericidal activity, then the fumigant can be applied to disinfect food materials and kitchen appliances contaminated with the pathogenic bacteria.