• Asian-Australasian Journal of Animal Sciences
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• 제16권5호
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• pp.706-713
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• 2003

Two experiments were conducted to evaluate the efficacy of dietary FERMKIT, a commercial toxin binder consisting of probiotic-fermented natural product containing chitin, chitosan and chitosan oligosaccharides ($FERMKITO^{(R)}$, EASY-BIO SYSTEM, Inc., Korea), in binding aflatoxin (AF) and zearalenone (ZEN) and ameliorating their mycotoxicity in meat type ducks. FERMKIT was supplemented to AF contaminated diets (at 120 ppb) at either 0.3 or 0.6% in experiment 1 and to ZEN contaminated diets (at 150 ppb) at 0.6% in experiment 2. In experiment 1 body weight gains were reduced by 37% and mortality was increased by 18% in ducks fed diet contaminated with AF at 120 ppb compared to ducks fed control diet (<10 ppb AF) for the 4-wk experimental period. However, dietary FERMKIT supplementation effectively alleviated overall toxicity induced by AF. The significant treatment-related changes in feather growth, web-toe hemorrhage, leg deformity, liver paleness, organ weights, hematological values and serum biochemical values, as compared to the control, were observed. The FERMKIT supplementation significantly diminished the adverse effects of AF and restored all the parameters measured back (<0.05) toward the control values. These findings indicated that FERMKIT, when added at the levels of 0.3 or 0.6% in the 120 ppb AF diets, could modulate the toxicity of AF with percentage sorption capacity of 52.70% at the level 0.3% and 79.85% at the level 0.6% of the diets (experiment 1). In experiment 2, FERMKIT, when added at 0.6% to the 150 ppb ZEN diets for the 4-wk experimental period, diminished the toxicity as shown by body weight gain, weights of testicles, oviducts, Bursa of Fabricius and cloaca eversion score as compared with the controls (<10 ppb ZEN) and 150 ppb ZEN diet with no added FERMKIT. The findings indicated that FERMKIT could be protective against the effects of ZEN in young growing ducks with percentage sorption capacity of 67.11% as evaluated from toxicity index parameter measured when added at 0.6% of the diets containing 150 ppb ZEN.

• 수산해양교육연구
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• 제20권1호
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• pp.90-94
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• 2008

Growth and water quality in Japanese eel, Anguilla japonica ($6.0{\pm}0.9g$) fed extruded and paste type diets were compared for 8 weeks. Fish in the duplicate tanks were fed with one of three experimental diets: two different extruded pellet diets and one paste type diet. Six FRP tanks were used with stocking density of 3.6 kg per tank (3 m3). Restricted feeds (ca. 2% of body weight) were served twice daily. Weight gains were checked at the end of every two-week interval, and water qualities in terms of NH4-N and NO2-N were determined daily one hour after feeding in the morning. Water temperature, dissolved oxygen, and pH were constantly kept within the optimum range, while fifty percent of total water volume was changed daily. Eels fed the extruded pellet diets showed significantly better (P<0.05) growth performance than did eels fed the paste type diet. The amount of feed waste from the paste type diet was significantly greater than those from the extruded pellet diets (P<0.05). Ammonia (NH4-N) waste was significantly higher from the paste diet than from the extruded pellet diets (P<0.05). These results show that extruded pellet diets are better than the paste type diet for growth and water quality management in eel culture.

• 한국컴퓨터정보학회논문지
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• 제25권11호
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• pp.83-88
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• 2020

본 논문에서는 진보된 프리앰블 탐지 기술인 MIM을 무선 센서 노드에 적용하는 방안을 제시한다. 또한 MIM 기능을 탑재한 센서 노드들이 IEEE 802.15.4 방식의 센서와 경쟁할 경우 발생할 수 있는 처리량과 공정성 사이의 트레이드오프 관계를 분석한다. MIM 센서들은 IEEE 802.15.4 기반의 센서에 비해 추가적인 동시전송 기회를 가져 처리량 측면에서 이득이 생기는 반면 IEEE 802.15.4 방식의 센서 노드들은 MIM 센서 노드들의 동시다발적인 추가 전송으로 인해 전송 기회를 제한받는다. 성능 평가를 위해 파이썬으로 시험환경을 구축하고 상용 센서 노드의 설정값을 반영하여 모의시험을 수행한 결과 MIM을 적용한 경우 최대 40% 수준의 처리량 향상을 확인하였다. 한편 동시전송 임계값을 적절히 조절함으로써 처리량과 공정성 측면에서 균형을 맞출 수 있음을 확인하였다.

• 한국정밀공학회지
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• 제28권3호
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• pp.292-300
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• 2011

Control systems in machinery equipment provide correction signals to motion units in order to reduce or cancel out the mismatches between sensor feedback signals and command or desired values. In this paper, we introduce a simulator for control characteristics of machinery equipment. The purpose of the simulator development is to provide mechanical system designers with the ability to estimate how much dynamic performance can be achieved from their design parameters and selected devices at the designing phase. The simulator has a database for commercial parts, so that the designers can choose appropriate components for servo controllers, motors, motor drives, and guide ways, etc. and then tune governing parameters such as controller gains and friction coefficients. The simulator simulates the closed-loop control system which is built and parameter-tuned by the designer and shows dynamic responses of the control system. The simulator treats the moving table as a 6 degrees-of-freedom rigid body and considers the motion guide blocks stiffness, damping and their locations as well as sensor locations. The simulator has been under development for one and a half years and has a few years to go before the public release. The primary achievements and features will be presented in this paper.

• 한국환경보건학회지
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• 제18권2호
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• pp.102-105
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• 1992

냉각탑, 제지산업, 일반 산업용수 등에 사용되는 산업용 방부제의 유효 성분 isothiazolinone components 즉, 2-methyl-4-isothiazolin-3-one(unchlorinated compound)과 5-chloro-2-methy14-isothiazolin-3-one(chlorinated compound)을 고성능액체크로마토그래피로서 분리, 정량하였다. 역상의 C$_{18}$ column (15 cmX3.9 mm I.D.)을 사용하였으며 자외선 검출기의 파장 254 nm에서 methanol-0.4% acetic acid(40 : 60)의 이동상, methanol-0.4% acetic acid(30: 70)의 추출 및 주입용매 조건으로 HPLC 분리를 시도한 결과 unchlorinated compound는 10~32,400 mg/l 범위에서, 그리고 chlorinated compound는 120~107,400 mg.l의 범위에서 직선성을 보였다. 내부 표준물질로서 dimethyl phthalate를 사용하였으며, unchlorinated compound, chlorinated compound 및 내부 표준물질의 순서로 븐리가 일어났고 총 분리시간은 6.41분이었다. 상기의 조건으로 시험물질을 분석, 정량한 결과 예측농도치에 근접한 수치를 얻었다.

• 한국전자파학회논문지
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• 제21권9호
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• pp.1023-1029
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• 2010

본 논문에서는 PCS, WCDMA, 그리고 WiBro 대역에서 동작하는 이동 통신 기지국용 광대역 편파 다이버시티 안테나를 제안하였다. 본 안테나는 정사각 루프 형태의 다이폴 안테나와 마이크로스트립 급전 구조를 결합하여 설계하였다. 추가적으로 광대역 동작 시 반사판 구조에 의해 발생할 수 있는 방사 패턴 왜곡 현상을 초크(choke) 상자를 이용하여 개선하였다. 설계를 위한 모의 실험은 CST사의 MWS로 해석하였으며, 제작은 비유전율 3.33인 테프론 기판을 이용하여 제작하였다. 측정 결과, 대역폭(VSWR<1.5)은 640 MHz(1.75~2.39 GHz)를 얻었으며, 각 방사체 사이의 격리도는 -25 dB 이하를 얻었다. 그리고 PCS, WCDMA, WiBro 대역에서 최대 이득은 각각 8.9 dBi, 8.2 dBi, 8.6 dBi이다.

• 한국자동차공학회논문집
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• 제22권2호
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• pp.166-174
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• 2014

Fuel injection pressure has steadily increased in diesel engines for the purpose of improving fuel efficiency and cleaning exhaust gas, but it has now reached a point, where the cost for higher pressure does not warrant additional gains. Common rail systems on modern diesel engines have fuel pumps that are mechanically driven by crankshaft. The pumps actually house two pumping module inside: a low pressure pump component and a high pressure pump component. Part of the fuel compressed by the low pressure component returns to the tank in the process of maintaining the pressure in the common rail. Since the returning fuel represents pumping loss, fuel economy improves if the returned fuel can be eliminated by using a properly controled electrical fuel pump. As the first step in developing an electrical fuel pump the fuel supply system on a 6 liter diesel engine was modeled with AMESim to analyze the workload and the fuel feed rate of the injection pump, and the results served as basis for selecting a suitable servo motor and a reducer to drive the pump. A motor controller was built using a DSP and a program which controls the common rail pressure using a proportional control method based on the target fuel pressure information from the engine ECU. A test rig to evaluate performance of the fuel pump is implemented and used to show that the newly developed electrically driven fuel pump can satisfy the fuel flow demand of the engine under various operating conditions when the rotational speed of the pump is adequately controlled.

• 패션비즈니스
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• 제13권2호
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• pp.100-114
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• 2009

In Honam province, the cultural prototype are largely unknown to the people, also the research on this subject are scarce, the artistic excellence, somewhat under evaluated, both in our country and internationally. It is imperative that we develop the modern design using this prototype. thereby apply it to many areas of cultural products. We should extend the dimension not only to the local festival but also to the mass production resulting in the commercial gains. The Unjusa Buddha festival for promoting the public relation would be greatly benefited by using the concept of the temple, the local prototype, by which we expect to create a ingenious textile design pattern, coinciding with the main purpose of this study. The ancient material around Unjusa come to be the subject of our textile design by way of selecting the most remarkable ones of heritage among the materials of Unjusa. In the long run, the harmonious contrast of both traditional and modern image were sought in this study. Designed patterns were edited using Adobe Photoshop CS3, a multi-purpose graphic program and were simulated in the towel for visual presentation. The design is of two kinds, the one is of the free style using combinations of reclining Buddha, stone Buddha, stone pagoda, and geometric patterns freely not to be standardized. The other one is mixing of lotus pattern, reclining Buddha, and geometric patterns. These designs were applied delicately on the towel, necktie and handkerchief, and the various colors were suggested by the 6 color ways. The brilliance of our traditional cultural property should be noted by these designs and I hope that this study would be a help to develop our cultural prototype and make a product of using the outstanding heritage.

• Korean Chemical Engineering Research
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• 제51권3호
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• pp.370-375
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• 2013

상업용 막전극접합체를 사용하여 제작한 고분자전해질 연료전지의 CO poisoning 및 air bleeding 효과가 스택의 셀전압 성능에 미치는 영향을 분석하였다. 실험을 통해 확보한 동적 응답 데이터에 일차 미분방정식으로 표현되는 일차계 모델을 적용하여 정상상태 이득과 시간상수를 계산하는 방법으로 스택 셀전압의 응답 특성을 정량화하였다. 연료전지 개질기로부터 공급되는 개질 가스에 포함된 CO 농도가 1 ppm 증가할 때마다 셀전압은 1.3~1.6 mV 저하되고, CO 농도의 변화폭이 클수록 정상상태에 도달하기까지 걸리는 시간이 점점 짧아지는 것으로 분석되었다. CO poisoning에 의해 저하된 스택 성능을 회복시키기 위해 air bleeding을 수행할 경우, 주입하는 공기의 농도를 증가시킬수록 셀전압 상승폭(정상상태 이득)이 커지고 회복시간(시간상수)은 짧아지나, 1% 수준의 air bleeding만으로도 CO poisoning이 일어나기 전 셀전압의 87%~96%를 1~30 min 이내에 회복시킬 수 있는 것으로 분석되었다.

• 농업과학연구
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• 제34권2호
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• pp.143-150
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• 2007

본 연구는 항생제를 대체할 목적으로 동물체의 활성을 가져오는 원료로 알려져 있는 활성탄과 목초액, sodium bentonite, 홍삼박, 생균제를 선별하여 이들 원료로 구성된 항생물질 대체제를 개발하여 홀스타인 수송아지에 급여하였을 때 생산성에 미치는 효과를 규명하고자 수행하였다. 송아지의 일당증체량은 대조구(1.01kg), 처리구(1.01kg)간에 유의적인 차이가 없었고(P>0.05), 사료 요구율은 대조구 3.24에 비하여 처리구 2.80로 처리구에서 유의적인 개선효과를 나타냈다(P<0.05). 설사 발생률은 동일하였으나 분 상태는 처리구가 양호하였고, 호흡기 질병은 처리구에서는 발생하지 않았다. 분 중 $NH_3$ 농도는 대조구(6.33 ppm)에 비하여 처리구(2.67 ppm)에서 뚜렷한 개선 효과를 보였고(P<0.05), 혈액 수치는 대조구와 처리구가 유사하였다. 항생물질 대체제를 급여한 처리구가 시판 항생제 첨가사료 급여군(대조구)에 비하여 증체에서는 다소 낮은 성적을 나타냈지만 질병 발생 없이 유사한 성적을 낸 것은 대체물질이 가축 소화기관의 활성화, 사료의 소화율 증진 등에 영향을 나타내어 동물의 활력이 증진되므로 항생제의 사용 없이도 양질의 축산물을 생산할 수 있는 결과를 얻었다.