• 전력전자학회논문지
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• 제2권4호
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• pp.45-55
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• 1997

FA의 중요성이 증가함에 따라 AGV(Autonomous Guided Vehicle)의 역할 또한 중요시되고 있다. 본 논문은 인공 지능의 여러 방법론을 통합하여 하이브리드 형태의 제어기가 가질 수 있는 상호 보완적인 특징을 이용하고자 하며, 유전자 알고리즘에 의한 자기조직이 가능한 퍼지제어기로써 능동적이고 효과적인 AGV 제어기를 구성하고자 한다. 자기 조직이 가능한 퍼지 제어기는 구성하기 위하여 GA(Genetic Algorithm)를 사용하여 멤버십 함수와 제어 규칙을 최적에 근사하게 튜닝하였으며 제어 규칙의 자기 수정 또는 생성을 통하여 제어 성능을 향상시킨다.

• 복식문화연구
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• 제29권3호
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• pp.346-360
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• 2021

Universities have recently introduced problem-based learning (PBL) to various subjects to enhance problem-solving skills (including self-directed learning and small-group learning) required in industry. The PBL module was applied to the personal production process in a draping class. A study was based on a questionnaire after conducting two PBL modules with a group of students. Each PBL module included 'design analysis', 'presentation of flat sketch and draping plan', 'discussion of the plan', 'evaluation of the draping result and correcting the problem', and 'final evaluation of the completed project'. Results showed that satisfaction with the PBL method and its activities was higher than satisfaction with existing teaching methods. In particular, among the various components, the 'design analysis' and 'the presentation step of flat sketch and draping plan' stages were more helpful to students compared to small-group discussion. Moreover, the effects of PBL were observed through student reflection essays, in which students suggested that PBL was very effective in enhancing problem-solving through self-directed and small-group learning. Despite the overall satisfaction with PBL, students expressed some minor difficulties associated with awkwardness with a novel learning method, lack of diverse perspectives among each group, and poor communication skills. Therefore, the study shows that PBL is highly likely to be useful to students when they are solving pattern drafting problems and making samples through self-directed learning and small-group learning.

• 한국분말재료학회지
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• 제30권3호
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• pp.233-241
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• 2023

In this study, we evaluated the effects of acid leaching on the properties of Cr powder synthesized using self-propagating high-temperature synthesis (SHS). Cr powder was synthesized from a mixture of Cr2O3 and magnesium (Mg) powders using the SHS Process, and the byproducts after the reaction were removed using acid leaching. The properties of the recovered Cr powder were analyzed via X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), particle size analysis (PSA), and oxygen content analysis. The results show that perfect selective leaching of Cr is challenging because of various factors such as incomplete reaction, reaction kinetics, the presence of impurities, and incompatibility between the acid and metal mixture. Therefore, this study provides essential information on the properties under acidic conditions during the production of high-quality Cr powder using a self-propagating high-temperature synthesis method.

• Asian-Australasian Journal of Animal Sciences
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• 제33권11호
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• pp.1866-1872
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• 2020

Objective: The objective of the present experiment was to construct self-draining beds to keep surface bedding materials clean and dry for beef cattle comfort in a temperate climate. Methods: In Experiment 1, a self-draining bed was covered with sand at depths of 10 cm (S-10a), 15 cm (S-15), and 20 cm (S-20) respectively. In Experiment 2, self-draining beds of different sizes were covered with 10 cm of sand (S-10b) and wood shavings (WS) at depths of 15 cm and 20 cm (WS-15 and WS-20). Fifteen cattle were engaged to evaluate the comfort of self-draining beds covered with different bedding materials. Results: No cattle lay in the feed alley and cattle spent more time lying on S-10a than S-15 or S-20 in Experiment 1 (p<0.01). No difference in lying time was detected between S-15 and S-20 (p>0.05). In Experiment 2, no cattle selected the feed alley as the lying area. Cattle preferred WS-15 as the lying area and time spent lying on WS-20 was slightly higher than on S-10b (p<0.05). Feces weight was higher in the feed alley than in the different bedding areas in both Experiments 1 and 2 (p<0.01). Conclusion: Sand-bedding depth at 10 cm and WSs at 15 cm above the self-draining bed can provide for the lying comfort of beef cattle. Design of a special feed alley to hold most of the feces to keep bedding materials clean and dry is desirable for organic beef cattle in a loose barn.

• 상하수도학회지
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• 제27권2호
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• pp.223-232
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• 2013

In this study, carbon emissions and energy consumption were evaluated to establish a design strategy which has low energy consumption and carbon emission production, by using life cycle energy (LCE) and life cycle $CO_2(LCCO_2)$ calculation methods in life cycle management(LCM) tools. After improvement design projects, the energy consumption and $CO_2$ emission were calculated and compared in three sewage treatment plants (STPs), which are A STP, B STP, and C STP. The reduction of carbon emissions was 28,020.1 ton $CO_{2-}e/yr$, 37,399.6 ton $CO_{2-}e/yr$ and 8,788.3 ton $CO_{2-}e/yr$, respectively. Production of energy was 792 TOE/yr, 1,235 TOE/yr and 1,023 TOE/yr, respectively. As a result, the estimation of energy and energy self-sufficiency was 5.1 %, 14.5 % and 23.5 %, respectively. The result of this study shows the LCM can be contributed to establish strategy for energy and carbon emission reduction in sewage treatment plants.

• 대한지역사회영양학회지
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• 제2권4호
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• pp.605-615
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• 1997

The job characteristics and competencies of 285 dietitians in employee foodservices were investigated by worker-oriented job analysis methodology. The purposes of this study were to : a) determine the knowledge, abilities, skills and other characteristics(KASO) needed for dietitians in two types of employee foodservice groups(self-operated vs. contracted), b) categorize KASO items by factor analysis and c) provide job information and job descriptions for dietitians in employee foodservices. The job analysis questionnaire was consisted of questions concerning the 134 KASO items. The questionnaire was mailed to 250 dietitians who are members of The Korean Dietetic Association Practice Group in self-operated foodservices(group A) and 250 dietitians who are employed in contracted foodservice companies(group B). Completed questionnaires were received from 285 dietitians(121 in self-operated, 164 in contracted) ; with response rate of 57%. Statistical data analysis was completed using the SPSS/win and the SAS/win packages. The results of this study can be summarized as follows. 1) Through factor analysis, the 134 KASO items were regrouped into 6 categories :‘primary dietetic tasks concerning menu management and administrative work regarding merchants’, ‘primary dietetic tasks concerning procurement and purchasing of food and supplies and meal production and service control’, ‘primary dietetic tasks concerning facility, sanitation and safety control’, ‘secondary dietetic tasks concerning nutrition education and research’, ‘secondary dietetic tasks concerning foodservice operation management’and‘human attributes’. 2) Analysis of the total scores(average scores of degree of frequency, importance and entry requirements of KASO items within 6 categories), group A showed high priorities placed on‘human attributes’, ‘procurement and purchasing of food and supplies and meal production and service control’, ‘menu management and administrative work regarding merchants’, ‘whereas group B showed high priorities placed on’‘human attributes’, ‘foodservice operation management’. (Korean J Community Nutrition 2(4) : 605-615, 1997)

• Advances in concrete construction
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• 제13권5호
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• pp.349-360
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• 2022

The rising prices of landfills and the lack of cement production are motivating researchers to be more interested in using wastes to produce concrete mixtures materials. The use of waste materials such as eggshell and matakoline waste not only reduces landfill costs and space, but also reduces the cost of cement production for the concrete mixture. However, recycling waste materials has become critical in order to effectively manage environmental sustainability. The purpose of this paper is to investigate the appropriate properties of self-compacting concrete (SCC) by incorporating waste materials such as crushed ceramics as coarse aggregate and nano egg shell (NES) and nanoclay (NC) as cement replacements. Fresh properties of SCC, such as segregation, flow time and diameter, V-funnel, H2/H1 ratio, and fresh unit weight of concrete mixtures, as well as hardened properties, such as 7, 14, and 28 days compressive strength and 28 and 90 days flexural strength, were measured for this purpose. The presence of NC in the SCC mixture enhanced the compressive strength of the concrete when 5% of NES was added or in the case without the addition of NES compared to the control mixture. The flexural strength enhanced with the incorporation of NC in the SCC increased the flexural strength of the concrete compared to the control mixture, but the incorporation of 5% of NES decreased the flexural strength compared to the mixtures with NC. These results prove the possibility of using crushed ceramics as the coarse aggregate, and NES and NC as substitutes for 5, 7, and 10% of the cement in SCC, because the properties of such SCC in hardened and fresh states are satisfactory.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.355-355
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• 2017

South Korea is largely dependent on imports of forage crops. In order to raise the self-sufficiency rate of forage crops, it is necessary to cultivate forage crops in 135,100 ha reclaimed land of South Korea. This study was conducted to investigate the growth of halophytes and forage crops in order to search for stable plants on reclaimed land. The plants were cultured in Hoagland solution and grown at 0%, 0.5%, 1.0% and 2.0% of salt concentrations. Plants with good growth at 0.5% of salt concentration were halophytes such as Suaeda asparagoides and Salsola komarovii. Salicornia herbacea and Suaeda maritima showed good growth at 2.0% salinity, and Suaeda maritima showed stable growth at all of salt concentrations. In conclusion, Suaeda asparagoides showed the best growth at 0.5% of salt concentration and was considered the most biomass at reclaimed land in Korea with less than 0.5% of salt concentration.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1999년도 추계 학술대회지
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• pp.145-167
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• 1999

Our self-sufficiency of food has become less than $30{\%}$ and our nation is highly dependant on world's grain market for food. which is unstable in long term due to the world population growth faster than food production. Therefore, it is a great possibility that food might become a political weapon by way of its global shortage. its purchasing difficulty in international free trade market. and the resultant price rising. Our maximal capability of food production has become the most outstanding problem in the dimension of future food security. It would be the utmost scheme for maximal production of food to realize the maximal utilization of arable land through the enlargement of sufficient farming land and the conversion of rotation system for the more grain production. Extensional enlargement of arable land can be positively executed through the development of farming land in domestic and abroad countries. The readjustment of arable land and the installation or irrigation and drainage system can enforce the farming basement for maximal utilization of arable land through the improved rotation between paddy and upland. The prevention policy against farming land encroachment should be strictly executed through grain production encouragement on resting or marginal lands and regulation of utilization conversion for the other than food production on high grade farming lands. It is also required urgently to develope high yielding and high quality varieties through advanced genetic technology for the improvement of unit area yield, especially of wheat, corn. and soybean we import in large quantity The maximal utilization of arable land for the highest production of food can be realized through rational rotation system, the most adaptable crop cultivation on the suitable land, and the most optimal fertilization through the GIS analysis of agricultural environment information on the basis of the computerized soil resource data on super detailed soil maps(1:5000) surveyed plot by plot of whole nation.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1998년도 21세기 한반도 농업전망과 대책(한국작물학회.한국육종학회 공동주관 심포지움 회보)
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• pp.249-265
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• 1998

The yearly consumption of soybean ranged from 1.5 to 1.7 million tons in Korea during 1995-1997 with an increasing trend of annual consumption by 60,000 tons. Gross consumption of soybean was 1.74 million tons in 1997: 1.292 million tons for feed, 0.433 million tons for food and its processing, and 15,000 tons for seed and other uses. Particularly, Korea totally depends upon imports of soybean for feed and oil. Only about $40{\%}$ of soybeans used for food and its processing are supplied through domestic production. Korean markets will be open to foreign agricultural products except for rice in 2004 when the Uruguay Round treaty is completed. According to the Korean Rural Economics Institutes reports, soybean consumption in 2004 is expected to be 1.87 million tons that is higher than that in 1997 by 0.13 million tons. In order to meet the need for soybean, Korean government planned to supply from 0.17 million tons of domestic production plus 1.7 million tons of imports, and also planned to raise the self-supply rate of $9.1{\%}$ in 2004 from $8.6{\%}$ in 1997. According to the USDA reports on international soybean production and consumption, its production is expected to be 150 million tons over the world and the international market prices for soybean will be unstable in 2004. Based on these reports, international soybean trade capacity will be 36 million tons in 2004 that is lower than 39 million tons (accounting for $25{\%}$ of gross production) in 1597. Also, a term-end stock in 2004 is estimated to be 9.6 million tons that is low as compared to 18.6 million tons In 1997, In coping with domestic and international soybean production, consumption and supply, and further possible food crisis, national policies and continuous efforts are necessarily required to promote domestic production and to reduce imports of soybean.