• 상하수도학회지
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• 제22권3호
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• pp.343-350
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• 2008

Many reports have warned of insufficient water supply in most countries in future and prospected providing safe and clean water become more difficult by lack of access to sustainable drinking water resources. Several facts and figures explained the impact by natural climate change and human activity results in the water scarcity and deterioration. Among many scientific solutions, the seawater desalination using a reverse osmosis membrane, so called SWRO (Seawater Reverse Osmosis) process, has been recognized as one of the most promising alternatives because of its stability and efficiency in producing large amount of drinking water from seawater through desalination by membrane filtration. Recently, in Korea, numerous researches are conducted to develop more productive and cost effective SWRO process for its wide implementation. The objective of this paper is to review the patents concerning SWRO technologies involving the plant engineering, maintenance including pretreatment of seawater and fouling control, module design, and mechanical units development for energy saving. The patents in Korea, U.S., Japan, Europe, and PCT were intensively researched and analyzed to provide the state of the art as well as leading edge technology on SWRO. This information can hopefully suggest meaningful guidelines on future research and development.

• Asian-Australasian Journal of Animal Sciences
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• 제18권5호
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• pp.686-691
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• 2005

Prolactin is considered to influence the taking of pauses in between ovulatory sequences in White Leghorn hens. Therefore modulating concentrations of prolactin using bromocriptine - a dopamine agonist during early life (17 to 36 weeks of age) could overcome the inhibitory effects of high concentration of prolactin on ovarian activity. The effect of modulation of prolactin concentration on egg production, sequence length and inter sequence pauses were studied by analyzing the oviposition records from 19 to 72 weeks were studied and compared with untreated controls. Bromocriptine administered subcutaneously (100 $\mu$g kg$^{-1}$ body weight or orally through feed (640 $\mu$g day$^{-1}$ bird$^{-1}$) resulted in a steady and sustained decrease in prolactin levels (p<0.01) during and after the withdrawal of treatment up to one reproductive cycle (72 weeks of age). The treated birds had comparatively longer sequences (p<0.01) and fewer pauses (p<0.01). Egg production increased (p<0.01) by fourteen per cent through subcutaneous administration and eleven per cent through oral feeding, over the control birds. It is concluded that the physiological pauses that occur during ovulatory sequences can be disrupted effectively using bromocriptine. Prolactin levels are modulated which may interfere with the follicular recruitment and subsequent oviposition thereby improve egg laying potential of the bird.

• 디자인학연구
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• 제20권2호
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• pp.103-116
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• 2007

Art education in design has repeatedly stressed the importance of developing creativity. In the digital period, however, which shows rapid change in both forms and contents, it needs to be equipped with more flexible and systematic ways of approaching to the creativity development, especially involved with cultural diversity of the digital world. This paper primarily proposes a maximally efficient, productive creativity learning program in which the integration of expressive media and communication generates a comprehensive network of communicative information in the development of digital technologies, which, consequently, brings forth valuable cultural contents of art. The amalgamation of Won (2006)'s Prism Effect, with distinctive three devices, and the facilitator factors, with two different facilitators such as self-controlled and controlled plays, would function as a catalyst for cultural diversity in the digital forms and contents of art. And this will, consequently, result in producing a number of practices that can be classified and assorted for a later performance. This paper thus suggests a roadmap of how to develop the creativity learning program in which two categories of facilitators based on three thinking devices function to classify four activities. In addition, selected activities are shaped as a creativity learning program by generating learning practices with the formalizing instructional strategy that fit into a specialized educational environment and learners. The samples of loaming practice design show guidelines for practice and the results of learning activity. Therefore, the eventual goal of this paper would be to establish a creativity learning program that constitutes a highly systematized and modularized database to maximize the efficiency and productivity of the creativity development.

• 조명전기설비학회논문지
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• 제22권10호
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• pp.111-117
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• 2008

일반적으로 산업현장에서 널리 사용되는 유도전동기는 상용인버터를 이용하여 속도제어를 하게 된다. 상용인버터로 구동되는 유도전동기는 인버터의 고속 스위칭에 의한 마이크로 서지전압을 발생한다. 이러한 마이크로 서지는 전동기의 소손뿐 만아니라 PLC 제어계통에 있어서 노이즈 문제를 발생하며, 생산 활동에 막대한 지장을 초래하게 된다. 본 논문에서는 마이크로 서지의 발생 메커니즘을 살펴본 후 전동기 소손 방지를 위한 대책을 제시하고 인버터 출력단에 LCR 필터를 부착하여 실험하였으며 결과로 마이크로 서지전압이 저감됨을 확인하였다 또한 PLC 제어계통의 노이즈 억제에 대해 이론적 고찰을 통해 대책도 제시하였다.

• 한국항해항만학회지
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• 제31권2호
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• pp.141-149
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• 2007

The competitiveness of container terminals hinges on minimizing the time vessels spend in port and on schedule services. Many previous researches on container terminals have tried to optimize the equipment allocation plan and to improve the activity of resources. Nevertheless, there have been few researches conducted on yard tractors, which move containers between the quay and the yard. The aim of this study is to propose the use of Real Time Location Systems (RTLS) based Dynamic Planning for yard tractors. Only RFID (Radio Frequency Identification) tags, which are attached to yard tractors, are able to support RTLS implementation. The system can provide real time job ordering in terms of load balancing using the information on location, in regards to the movement of yard tractors. This study will present the practical feasibility of RTLS, which can ultimately reduce the congestion of Hot Queues in container terminals. As a result, container terminals can be more productive and competitive. In order to accomplish the purpose of this study, we examined previous studies on the competitiveness of container terminals and summarized the potential of RTLS using RFID. In addition, we identified the role of yard tractors and proposed the two rules of Dynamic Planning for the yard tractors. We then fulfilled computational experiments on how yard tractors carrying containers by RTLS ordering Finally, the benefits and the implications of this study are discussed.

• 한국경제지리학회지
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• 제9권2호
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• pp.243-260
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• 2006

유럽연합의 자동차산업은 생산공간의 확대와 경제통합의 심화 그리고 미국과 일본 등 역외 완성차업체의 시장진출로 생산방식 및 생산체계의 지리적 재구조화가 형성되고 있다. 생산활동의 글로벌화와 지역화로 완성차업체간 경쟁이 심화되면서 비용절감과 다양한 제품개발, 신속한 제품혁신 위해 생산방식이 플랫폼의 공용화와 모듈화된 부품조달체계로 변화되고 있다. 모듈화된 부품조달방식의 채택으로 완성차업체와 부품공급업체간의 역할이 재조정되고 생산활동과 관련된 다양한 생산기능들의 지리적 재구조화가 활발히 진행되고 있다. 새로운 생산방식과 생산공간 확대, 그리고 경제통합의 심화에 의해 제공된 기회를 이용하기 위해 제품의 특성과 생산활동의 기능별 특성에 따라 공간적으로 전문화되고 집적화되는 경향을 보이고 있다. 고가모델의 생산과 연구 개발 및 전문서비스 기능은 중심부에서 강화되고 저가모델의 생산과 일반화된 장비 및 부품생산 기능은 주변부에 분산 입지하는 계층적 구조가 심화되고 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제26권7호
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• pp.987-994
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• 2013

The purpose of this study was to evaluate the effect of natural clinoptilolite (NCLI) and modified clinoptilolite (MCLI) on broiler performance, gut morphology, intestinal length and weight, and gut digestive enzyme activity. A total of 240 d-old male chicks were randomly assigned to 3 treatments, each of which comprised 8 pens of 10 chicks per pen. Birds in the control group were fed the basal diet, while those in the experimental groups were fed diets supplemented with NCLI at 2% (NCLI group), or MCLI at 2% (MCLI group), respectively, for 42 d. Compared with the control, supplementation with NCLI or MCLI had no significant (p>0.05) effects on productive parameters from d 1 to 42. Supplementation with NCLI or MCLI had no influence on the relative length and weight of small intestine at d 1 to 21. But supplementation with NCLI or MCLI significantly reduced the relative weight of duodenum. Supplementation with MCLI and NCLI was associated with greater (p<0.05) villus height in the jejunal and ileal mucosa compared with those areas in the controls from d 1 to 42. However, supplementation with NCLI and MCLI had no significant (p>0.05) influence on the crypt depth in the jejunal and ileal mucosa compared with those in the controls. The addition of either NCLI or MCLI to the diet improved the activities of total protease, and amylase in the small intestinal contents. In conclusion, supplementation with NCLI or MCLI in diets improved intestinal morphology, increased the intestinal length and weigh and gut digestive enzyme activity.

• 한국콘텐츠학회논문지
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• 제13권6호
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• pp.246-259
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• 2013

본 연구는 60세 이상 노인들을 대상으로 노인들의 생활만족도에 미치는 결정요인들의 차별적 영향을 탐구하는데 그 목적이 있으며, 이를 위해서 노인 생활만족도 결정요인으로 다양한 건강, 경제, 여가활동, 사회적 지지 및 심리 요인 관련 변수들을 포괄적으로 검토하였다. 본 연구를 위해 서울 소재 10개 노인종합복지관, 노인대학 및 노인문화센터의 여가활동 프로그램에 참여하고 있는 60세 이상 노인 347명을 대상으로 자료를 수집하였다. 자료수집방법으로는 구조화된 설문지를 사용하였으며, 가설검증을 위한 주된 자료분석방법으로는 구조방정식모형분석기법을 사용하였다. 연구결과 건강요인인 주관적 건강상태, 경제적 요인인 주관적 경제수준, 여가활동요인인 생산적 여가활동과 소비적 여가활동, 사회적지지 요인인 배우자 지지와 자녀지지 그리고 심리적 요인인 자아존중감과 외향성이 노인의 생활만족도에 유의미한 영향을 미치는 것으로 나타났다. 본 연구결과가 갖는 이론적 실천적 함의를 논의하고 향후 연구방향을 제시하였다.

• 대한안전경영과학회지
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• 제16권2호
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• pp.217-230
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• 2014

The purpose of this study is to develop the Generalized Depreciation Function (GDF) and Winfrey Depreciation Function (WDF) by reviewing methods for the depreciation accountings. The Depreciation Accounting Models (DAM), including straight-line model, declining-balance model, sum-of-the-year-digit model and sinking fund model presented in this paper, are reclassified into the charging pattern of increasing type, decreasing type and constant type. This paper also discusses the development of the GDFs based on convex type, concave type and constant type according to the demand pattern of product, frequency of plant usage, deterioration of time, relative inadequacy, Capital Expenditure (CAPEX) and Operating Expenditure (OPEX) of the Total Productive Maintenance (TPM). The WDFs presented in this paper depict a sudden degradation of plant performance by measuring the change of TPM activity at the midpoint of useful life of asset. The WDFs are classified into left-modal type, symmetrical type and right-modal type by varying the value of skewness and kurtosis. Moreover, three increasing patterns, such as convex, concave and linear types, are used in this paper to present the distinct identification of WFDs by using Instantaneous Depreciation Rate (IDR) in terms of Performance Depreciation Function (PDF) and Depreciation Density Function (DDF). In order to have better understanding of depreciation models, the numerical examples are used for evaluating the Net Operating Less Adjusted Tax (NOPLAT) and Economic Value Added (EVA). It is concluded that the depreciation models showing a large dispersion of EVA require the adjustment of NOPLAT and Invested Capital (IC) based on the objective cash basis and net operating activity for reducing the variation of EVA.

• 한국산림과학회지
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• 제105권2호
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• pp.208-215
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• 2016

우리나라 자생수종인 정금나무는 낙엽활엽관목으로 열매는 식약용으로 사용되어 왔으나 기능성성분 함량 및 항산화 활성에 관한 연구는 미진한 실정이다. 따라서 본 연구는 국내 자생 정금나무 4집단 24개체의 열매에 대한 형태적 특성, 식물생리활성물질(폴리페놀, 플라보노이드, 안토시아닌) 및 항산화활성을 분석하였다. ANOVA 분석결과 모든 특성들에서 집단 및 개체간의 유의적인 차이가 인정되었다. 총 페놀 함량은 4.40~10.58 mg GAE/g, 총 플라보노이드 함량은 2.02~8.09 mg NE/g, 총 안토시아닌 함량은 232.5~684.3 mg CGE/100g, 환원력은 0.15~1.43, DPPH 자유라디컬 소거능은 400 ppm 농도에서 49.1-97.5% 범위를 각각 나타냈다. 특히, 정금나무 열매의 기능성 성분 함량 및 항산화활성이 국내재배 및 북미산 블루베리에 비해 우수한 것으로 나타나 육종소재 및 기능성 성분 소재로서의 이용 가치가 높은 수종으로 판단된다.