• Resources Recycling
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• v.22 no.2
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• pp.22-28
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• 2013

In the present study, the possibility of recovering and recycling the silicon carbide(SiC) from a silicon sludge by removing Fe and Si impurities was investigated. Si and SiC were separated from the silicon sludge using centrifugation. The separated SiC concentrate consisted of Fe, Si and SiC, in which Fe and Si were removed to recover the pure SiC. Leaching with acid/alkali solution was compared with the vapor-phase chlorination. The Fe concentration removed in the SiC was 49 ppm, and it was separated by leaching with 1 M HCl solution at $80^{\circ}C$ for 1 h. The Si concentration removed in the SiC was 860 ppm, and it was separated by leaching with 1M NaOH solution at $50^{\circ}C$ for 1 h. The SiC concentrate was chlorinated in a tubular reactor, 2.4 cm in diameter and 32 cm in length. The boat filled with SiC concentrate was located at the midpoint of the alumina tube, then, the chlorine and nitrogen gas mixture was introduced. The Fe and Si concentration removed in the SiC were 48 ppm and 405 ppm, respectively, at $500^{\circ}C$ reactor temperature, 4 h reaction time, 300 cc/min gas flow rate, and 10% $Cl_2$ gas mole fraction.

• The KIPS Transactions:PartB
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• v.16B no.5
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• pp.403-410
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• 2009

The two-dimensional bin packing problem(2D-BPP) has been known to be NP-hard, and it is difficult to solve the problem exactly. Many approximation methods, such as genetic algorithm, simulated annealing and tabu search etc, have been also proposed to gain better solutions. However, the existing approximation algorithms, such as branch-and-bound and tabu search, have shown the low efficiency and the long execution time due to a large of iterations. To solve these problems, we first define the fitness function to simplify and increase the utility of algorithm. The function decides whether an item is packed into a given area, and as an important information for a packing strategy, the number of subarea that can accommodate a given item is obtained from the variant of the fitness function. Then we present a heuristic algorithm BF for 2D bin packing, constructed by the fitness function and subarea. Finally, the effectiveness of the proposed algorithm will be expressed by the comparison experiments with the heuristic and the metaheuristic of the literatures. As comparing with existing heuristic algorithms and metaheuristic algorithms, it has been found that the packing rate of algorithm BP is the same as 97% as existing heuristic algorithms, FFF and FBS, or better than them. Also, it has been shown the same as 86% as tabu search algorithm or better.

• Journal of Technology Innovation
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• v.25 no.4
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• pp.285-311
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• 2017

PSL-II Accelerator is a large-scale research facility located in Pohang, which was established in 1988 and operated since 1995. It is a program to be promoted to contribute to basic science research in Korea by applying it to cutting-edge research in the field of basic and applied science. It is estimated that around KRW 787.9 billion was invested for construction and operation in the near-30-year period until 2016. Although there have been various evaluations of the need, importance and effectiveness of accelerator in relation to the accelerator policy, most of them emphasize the successful outcome of the present time and suggest the government's need for sustained support in the future or suggest policy implications for improving the policy in a comprehensive manner. And there was no systematic analysis of the results on a comprehensive review or the various policy evaluations of the accelerator policy. In this study, three stages of PSL-II accelerator program were evaluated, and five main criteria of policy activity were considered. The purpose of this study is to suggest the policy implications related to the principles of policy activity which is essential in construction and operation of similar large-scale research facilities in addition to PSL-II accelerator.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.6
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• pp.544-549
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• 2009

Failure to use effective methods of reduction, fixation and immobilization may lead to osteomyelitis with the exposed necrotic bone, as the overzealous use of transosseous wires & plates that devascularizes bone segments in the compound comminuted fractures of mandible. Once osteomyelitis secondary to fractures has become established, intermaxillary fixation should be instituted as early as possible. Fixation enhances patient comfort and hinders ingress of microorganisms and debris by movement of bone fragments. Teeth and foreign materials that are in the line of fracture should be removed and initial debridement performed at the earliest possible time. Grossly necrotic bone should be excised as early as possible ; no attempt should be made to create soft tissue flaps to achieve closure over exposed bone. The key to treatment of chronic osteomyelitis of the mandible is adequate and prolonged soft tissue drainage. If good soft tissue drainage is provided over a long period, sequestration of infected bone followed by regeneration or fibrous tissue replacement will occur so that appearance and function are not seriously altered. Localization and sequestration of infected mandible are far better performed by natural mechanism of homeostasis than by cutting across involved bone with a cosmetic or functional defect. As natural host defenses and conservative therapy begin to be effective, the process may become chronic, inflammation regresses, granulation tissue is formed, and new blood vessels cause lysis of bone, thus separating fragments of necrotic bone(sequestra) from viable bone. The sequestra may be isolated by a bed of granulation tissue, encased in a sheath of new bone(involucrum), and removed easily with pincettes. This is a case report of the long-term conservative drainage care in osteomyelitis associated with mandibular fractures.

• Strategy21
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• s.43
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• pp.5-28
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• 2018

The tensions between the U.S and China, which form the two pillars of the G2 era, seem to have persisted even after the Trump administration inaugurated. The strong confrontation between the two in recent foreign security issues may drive to develop an inadvertent military conflict, and it is high likely to occur in the maritime are. The purpose of this study is not only to analyze the balance of modernized naval forces in the PLAN through naval strategy changes and weapons system modernization trend, but also to predict the impact of the geographical proximity difference on the balance of naval forces in the disputed areas. It examined the impact of distance and geography on naval power by assessing the modernization pattern of the PLAN and capabilities in the context of two scenarios at different distances from China by 2020: one centered on Taiwan and the other on the Spratly Islands. The PLAN's strategy had impact on operational concept and forces construction. First, from the viewpoint of operation operational concept, it can be seen that the passive defense is changing into active defense. Second, in terms of power construction, it can threaten the surface and submarines of U.S power from a distance. And they generated follow three features; The ocean is not the focus of Chinese submarines, Horizontal and vertical expansion of Chinese naval vessels, The improvement of the suppression ability as the Chinese naval modernization ratio increases. The strength of the PLAN is dominant over the U.S in terms of reserves, and it can complement the qualitative deterioration by utilizing nearby bases in the vicinity of the mainland, such as the Taiwan Strait. However, due to the shortage of aircraft carriers, there is a possibility that it will take some time to secure the advantage of air and ocean in the amphibious operation. Therefore, as the dispute is prolonged, China may fail to achieve its original goal. In addition, the lack of cutting edge Commanding Ships may bring to weaken the C2 capabilities. At results, it is expected that PLAN will not be able to have a superiority in the short term due to lagging behind U.S advanced technology. Nevertheless, PLAN has strengthened its naval power through modernization sufficiently and it is highly likely to use force. Especially, it is more likely in the region where the naval power operation like the Taiwan Strait is possible with the almost equality to that of the United States. China will continue to use its naval forces to achieve a rapid and decisive victory over U.S in the close area from the land.

• Journal of the Korean Society of Costume
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• v.19
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• pp.105-125
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• 1992

The research, aiming an automatic pattern design of Korean Costume by utilizing CAD system, tried Grading, Seaming and Marking with a theme of girl's color-strip blouse & skirt. The content & conclusion of the research can be outlined as follows; 1) As we reviewed the current situation of Korean costume which becomes more likely celebrational or festival costume, while the demand of it is getting increase, it's being dealt mostly as ready-made dresses with different qualities & designs. Especially childrens ready-made ones were highly demanded to be picked up as the theme. 2) For the original drawing of children's color-strip blouse & skirt, Kyung-Ja Park's drawing method was used here, and for the substitute of particular body parts absolute size, Joo-Won Lee's standard size chart from a size-study by ages. 3) To work with CAD system we had input master pattern, drawn for age 5 as basic size, then graded six step-sizes for 1-11 years old. For add-subtract of particular body parts size, we graded through computing the standard variation among items to get the pattern developed into ready-made standard size, we can make precise plotting by grading wanted size very rapidly if we correct the rule of changed items different from standard size to make utilization possible enough with easy order method of ready-made Korean Dress. 4) We produced Marker after attaching a margin to seam accordingly by parts for each pattern using P/D/S to mark, In mass gament-cutting, the loss of time and material can minimized. In this research the apparel CAD system which has been utilized and only be western fashion industry was introduced for the design of ready-made Korean costume and utilized it in Grading, Marking which are critical steps to improve productivity and have reported the result in the research. Thus we expect that less cost, improved productivity and better quality with minimized loss of material from marking as well as from prompt and precise size-drawing. Furthermore the utilization of CAD system is considered as an effective one in terms of the research & the development to remove effective one in terms of the research & the development to remove irrational elements in the design and production process of Korean costume as well as in terms of the study of Korean Costume development through creative works of Korean Costume.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.246-250
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• 2010

This study was conducted to find out the propagation method of a rare variety Daphne kiusiana Miq. in Korea through softwood cuttings. Daphne kiusiana Miq are the evergreen broad leaf tree which have lived in the southern part of Korea. The flowering time of Daphne kiusiana Miq is early spring and the flower has an attractive fragrance. Generally, plants are dioecious and only the male plants are found in Korea. Propagation by seed is very difficult in this tree. Softwood cuttings were taken to establish an efficient propagation method in Daphne kiusiana Miq Cuttings were grown in perlite:vermiculite (1 : 1), perlite, vermiculite, sand rooting media under shaded greenhouses during summer in 2007. The rooting rates of cuttings were 86.7%, 95%, 75% and 95% in perlite:vermiculite (1 : 1), perlite, vermiculite and sand media, respectively. Softwood cuttings taken on July and rooting at $27^{\circ}C$ were significantly improved the growth and rooting rates. Softwood cutting can be an effective means of propagation in Daphne kiusiana Miq.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.303-303
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• 2017

Japanese agriculture has faced to several threats: aging and decrease of farmer population, global competition, and the risk of climate change as well as harsh and variable weather. On the other hands, the number of large scale farms is increasing, because farm lands have been being aggregated to fewer numbers of farms. Cost cutting, development of efficient ways to manage complicatedly scattered farm lands, maintaining yield and quality under variable weather conditions, are required to adapt to changing environments. Information and communications technology (ICT) would contribute to solve such problems and to create innovative technologies. Thus we have been developing an early warning and decision support system to reduce weather and climate risks for rice, wheat and soybean production in Japan. The concept and prototype of the system will be shown. The system consists of a weather data system (Agro-Meteorological Grid Square Data System, AMGSDS), decision support contents where information is automatically created by crop models and delivers information to users via internet. AMGSDS combines JMA's Automated Meteorological Data Acquisition System (AMeDAS) data, numerical weather forecast data and normal values, for all of Japan with about 1km Grid Square throughout years. Our climate-smart system provides information on the prediction of crop phenology, created with weather forecast data and crop phenology models, as an important function. The system also makes recommendations for crop management, such as nitrogen-topdressing, suitable harvest time, water control, pesticide spray. We are also developing methods to perform risk analysis on weather-related damage to crop production. For example, we have developed an algorism to determine the best transplanting date in rice under a given environment, using the results of multi-year simulation, in order to answer the question "when is the best transplanting date to minimize yield loss, to avoid low temperature damage and to avoid high temperature damage?".

• Journal of Food Hygiene and Safety
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• v.4 no.2
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• pp.103-108
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• 1989

Three mushroom cannerries were selected by size which are representative vegetable processing firms in korea for monitoring microbial contamination of processing water, washing water, mushroom before and after washing through first and second washing tanks and, blanched and prolonged mushroom for certain time at room temperature. Total contamination degree was expressed as colony forming unit (CFU) of mesophilic aerobes. The contamination degree of processing water was $10^{2}\;CFU/100\;ml$ and washing water in first and second washing tank were 10 to 100 times higher than processing water. When 2.3 tons of washing water was used for washing 1 ton of mushroom, washing effect was showed by reduction of microbial load but cutting it to 1.8 tonsIl ton of mushroom, microbial load was higher than that of raw mushroom level. Blanching reduced microbial load to 50-500 CFU/g of blanched mushroom and it was not seen much increase of CFU in blanched mushroom left at room temperature for 3 hours in $16^{\circ}C$ processing water. Just after injection of $80^{\circ}C$ brine in container, CFU/ml of brine in container was $84{\times}10^{4}$ but it was increased rapidly to $20{\times}10^{7}$ after 2 hours at ambient temperature.

• Journal of Korean Home Economics Education Association
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• v.4 no.1
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• pp.87-95
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• 1992

The purpose of this study is to suggest how we can get over the difficulties of practical drill under experimentation concerning the units of making clothes in the curriculum of home economics. The import of this study was based on the results of the preceding studies the field of the making Korean clothes, from the standpoint of the teaching tools and teaching materials by the use of VTR, is one of the most insufficient. On the one hand, the teaching procedure here a VTR, running 34 minutes or so, was made up with the process of making Korean men’s slacks, and was led by the researcher’s own. The contents of the lesson are as follows： the shape of Korean clothes, the name of each part, the process of drawing, cutting and sewing, and the items of evaluation and arrangement. On the other hand, the two comparative groups were made to compare one with the other： One group was taught by help of VTR media, and the other by the model performance and explanation of the instructor’s own. All of the statistical data were analyzed in terms of SPSS/PC, and t-verification was made, to make difference between the two, after standard deviation was calculated according to the classified domains. The consequences of the test research are shown as below： 1. The difference of understanding was obviously made in considering that the group made a better score than the comparative one in understanding to process of making Korean clothes. 2. The difference of skill was highly made in considering that the group made a better score than the comparative one in the practical drill of making Korean clothes. 3. The difference of interests was evidentally made in considering that the group made a better score than the comparative one in the stage of making Koran clothes. Such means that the motivation and attitude of the learners was made stimulate by the Audio-Visual material than by the traditional cramming method. 4. The difference of frequency was fairly made in considering that the experimeatal group made a better score than the comparative one in the frequency of individual teaching. 5. The difference of the efficiency of time-consumption was clearly made in considering that the experimental group made a better score than the comparative one. As the results of the research above, the medium of VTR proved to more effective to the achievement of schoolwork and the strategies of teaching. Therefore, more use of VTR media will help the instructors with the difficulties of practical drill in the whole process of making Korean clothes； Widely use of VTR media in teaching will be surely more fruitfull to the unit of making Korean clothes than teaching by explanation.