• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.659-664
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• 2000

Fuel-consumption and catalyst-out emissions of a parallel hybrid electric vehicle are affected by operating region of an engine. In many researches, It is generally known that it is profitable in fuel- consumption to operate engine in OOL(Optimal Operating Line). We established the mathematical model of a parallel hybrid electric vehicle, which is linear time-invariant. To operate an engine in OOL, we applied RHC(Receding Horizon Control) to the driving control of a parallel hybrid electric vehicle. And it is known that the RHC has advantages such as good tracking performance under state and control constraints. This RHC is obtained by using linear matrix inequality (LMI) optimization. In this paper, there are three main topics. First, without state and control constraints, the optimal tracking of OOL was simulated. Second, with state and control constraints by engine and motor performances, the optimal tracking of OOL was simulated. In the last, we studied on the optimal gear ratio. That is to say, we combined the RHC and the iterative simulation to extract the optimal gear ratio. In this simulation, the vehicle is commanded to track the reference vehicle trajectory and the engine is operated in the optimal operating region which is made by the state constraints.

• International Journal of Automotive Technology
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• 제5권3호
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• pp.201-208
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• 2004

Response characteristics of the CVT system for a parallel hybrid electric vehicle (HEV) are investigated. From the experiment, CVT ratio control algorithm for the optimal engine operation is obtained. To investigate the effect of the CVT system dynamic characteristics on the HEV performance, a hardware in the loop simulation (HILS) is performed. In the HILS, hardwares of the CVT belt-pulley and hydraulic control valves are used. It is found that the engine performance by the open loop CVT ratio control shows some deviation from the OOL in spite of the RCVs open loop control ability. To improve the engine performance, a closed loop control of the CVT ratio is proposed with variable control gains depending on the shift direction and the CVT speed ratio range by considering the nonlinear characteristics of the RCV and CVT belt-pulley dynamics. The HILS results show that the engine performance is improved by the closed loop control showing the operation trajectory close to the OOL.

• 한국위성정보통신학회논문지
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• 제12권3호
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• pp.35-40
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• 2017

위성의 상태를 파악하기 위해 기존에는 OOL(Out-Of-Limit) 방식을 많이 사용하여 왔다. OOL은 특정 텔레메트리의 상위, 하위 문턱 값을 지정하여 해당 값을 벗어날 경우 문제가 발생한 것으로 인식 하는 방식이다. 이 방법은 파라미터의 특성을 파악하여 각각의 문턱 값을 정확히 설정해야 하는 전문 지식과 노력이 필요하고 텔레메트리 값이 문턱값 내에서 비정상적으로 변할 경우는 검출할 수 없다는 문제점이 있다. 이러한 문제를 극복하기 위해 본 논문에서는 위성이 정상 상태일 때 텔레메트리의 통계적 특징 중 러프집합을 이용하여 중요한 것을 선택, 적용하여 퍼지 모델을 구축하고 이상 상태를 구분하는 시스템을 제안한다. 정상 상태의 데이터만 이용하여 모델을 구축하기 때문에 출력값을 비교 하여 사전에 정의되지 않은 비정상 상태의 구분이 가능 하며 다양한 통계 값을 이용하기 때문에 전문 지식 필요 없이 문턱값 내에서 비정상적으로 변하는 텔레메트리를 검출할 수 있다. 제안한 시스템의 동작 확인을 위해 실제 저궤도 관측위성의 배터리 온도 텔레메트리를 적용하여 시험을 수행 하였고 비정규적 운영 상태에 대한 검출이 성공적으로 이루어 졌다.

• Journal of Periodontal and Implant Science
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• 제25권1호
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• pp.14-23
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• 1995

Cyclosporin A is a powerful immunosuppressive agent commonly used for patients receiving organ transplants. Like phenytoin and the calcium channel blockers, the drug is associated with gingival overgrowth. The purpose of this study was to compare the correlation with gingival overgrowth score and clinical indices(i.e, : plaque index, papillary bleeding index, probing depth) and correlation with gingival overgrowth score and microorganism distribution in use of phase contrast microscope. After renal tranplant, taking cyclosporin A 40 patients participating in this investigation. Post - transplatation cyclosporin medication period was average $17.53{\pm}15.75$ months. In previous study reported that gingival overgrowth is an adverse side - effects seen in about 25-81% of patient taking cyclosporin A. The results were as follows : 1. Gingival overgrowth prevalence in taking cyclosporin A patients was 77.5%. Prevalence rate of region was anterior region(26 teeth, 55.3%), molar region(14 teeth, 29.8%), premolar region(7 teeth, 14.8%) in turns. Gingival overgrowth score by Angelopoulos & Goaz method was molar region($1.56{\pm}0.81$), anterior region($1.52{\pm}0.75$), premolar region($1.14{\pm}0.90$) in turns. 2. Medication period was not correlation with gingival overgrowth score. 3. Clinical indices and gingival overgrowth score were as follows. 1) Plaque index and gingival overgrowth score was significantly correlated(p

• 한국식품과학회지
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• 제23권1호
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• pp.102-108
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• 1991

율무가루를 $35^{\circ}C$에서 6개월 동안 저장하면서 triglyceride조성의 변화를 연구하였다. 율무지방질은 28종류의 triglyceride로 구성되었으며, 이들 중 주요한 triglyceride 조성으로는 OOL(24.14%), OLL(24.06%), OOO(12.58%), POL(9.01%), POO(8.87%), LLL(7.91%), PLL(5.80%)였다.$35^{\circ}C$에서 6개월간 저장하는 동안에 linoleic aicd를 함유한 triglyceride인 OLL과 LLL은 각각 조성비가 24.06%에서 15.25%로 7.91%에서 2.92%로 감소되었으나, 상대적으로 oleic aicd를 함유한 OOO 및 POO 조성비는 각각 12.58%에서 23.77%로, 8.87%에서 12.62%로 증가하였으며, 미량으로 함유되었던 LLA(0.44%)와 PPLn(0.12%)는 저장동안에 소실되었다. 이와같이 triglyceride의 산화현상은 triglyceride를 구성하는 지방산의 이중결합의 수가 증가할수록 현저했으며, 특히 triglyceride에 함유된 이중결합의 총 수에 의해 영향을 받는 것이 아니라 triglyceride를 구성하는 지방산 각각의 불포화도에 의존하는 것으로 나타났다.

• 한국식품조리과학회지
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• 제6권4호통권13호
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• pp.27-32
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• 1990

Triglyceride는 구성지방산의 종류에 따라 분자종이 다양하게 존재하여 식품의 가공, 저장중에 있어서 유지의 물성변화 및 산화특성을 효과적으로 규명하기 위해서는 구성 triglyceride 분자종의 상세한 해석이 요구된다고 하겠다. 율무 지질의 triglyceride를 reverse phase HPLC UV detector 210nm에서 분석한 결과 6개의 peak로 분획되었다. 각 획분을 GC로 acycl 탄소수별로 분획하고, 다시 DEGS column을 이용하여 fatty acid 조성을 분석하였다. 이 세가지 결과로부터 triglyceride 조성을 산정한 결과 11개의 TG 조성을 추산하였으며, 그 중 주요 triglyceride로는 C18 : 1 C18 : 2 C18 : 2(OLL)이 38.2%, C16 : 0 C18 : 2 C18 : 3(PLLn)이 15.7%, C18 : 1 C18 : 1 C18 : 2(OOL)이 12.6%였다. 한편 capillary GC와 GC-MS로 같은 시료를 분석하여 분자종을 확인하는 작업을 계속하고 있으며 위의 결과와 비교하여 다음에 보고하고자 한다.

• 한국응용과학기술학회지
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• 제22권4호
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• pp.339-348
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• 2005

On the analysis of triacylglycerol (TG) from the kernels of Acanthopanax sessiliflorus by reversed phase-HPLC, it was separated into three main fractions of PN 44, 46 and 48, according to partition number (PN). On the contrary, it could be clearly classified into seven fractions of SMM, MMM, SMD, MMD, SDD, MDD and MDT by silver ion-HPLC by the number of double bond in the acyl chains of TG species. But resolution of so-called critical pairs of TG molecular species such as molecular pairs of $P_eLL$ $[C_{18:1{\omega}12}/(C_{18:2{\omega}6)2}]$ and OLL $[C_{18:1{\omega}9}/(C_{18:2{\omega}6)2}]$ and OOL $[(C_{18:1{\omega}9)2}/C_{18:2{\omega}6]$, and $P_eP_eL$ $[(C_{18:2{\omega}12)2}/C_{18:1{\omega}6]$ was not achieved $(P_e;$ petroselinic acid, L; linoleic acid, O; oleic acid). On the other hand, TG extracted from Aralia continentalis kernels were also fractionated into seven groups of SSM, SMM, MMM, SMD, MMD, SDD and MDD (S; saturated acid, M; monoenoic acid, D; dienoic acid) by silver ion-HPLC, although it's were classified into three groups of PN 44, 46 and 48 by reversed phase-HPLC. The fractions of SMM, MMM, MMD and MDD were divided into two subfractions, respectively; the fractions of SMM, MMM, MMD and MDD were resolved into the subfraction of $PP_e/P_e$ and POO (critical pairs from each other), that of $P_e/P_e/P_e$ and OOO, that of $P_e/P_e/L$ and OOL, and that of $P_e/L/L$ and OLL.

• 공업화학
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• 제27권6호
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• pp.664-668
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• 2016

무단 폐기물 투기로 인해 토양, 지하수, 하천 등 환경오염이 심각해지고 있다. 본 연구에서는 J시에서 발생된 무단 투기 유류를 분석함으로써 어떤 유종인지를 분석하였다. 물, 고형불순물, 유류 혼합물 형태를 전처리하여 균질한 유류성분을 얻은 뒤, 물성분석, 원소분석, 및 가스크로마토그래피를 이용해 분석한 결과, 11.8%의 산소함량, $-6^{\circ}C$의 유동점, 크로마토그램의 패턴 결과 식물성기름으로 판단하였다. 또한 어떤 식물성 기름인지 알기 위해 HPLC를 이용해 구성성분을 분석한 결과, LLO, OOL, POL이 높은 비율로 분석되어졌으며, 이는 대두유가 주성분이면서 다른 식물성기름의 혼합형태인 폐유로 최종 판단하였다. 본 연구를 통해 향후, 불법 투기되는 유류에 대한 유종 구분 및 오염원인자 판단을 위해 활용 가능할 것으로 판단된다.

• 대한기계학회논문집
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• 제17권9호
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• pp.2181-2190
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• 1993

An electro-hydraulic controlled rig type CVT(Continuously Variable Transmission) system was developed and its performance tests were carried out for the optimal operation. A CVT map was suggested based on the speed ration-axial force-torque relationship which was derived from the metal belt CVT mechanics. Also, a real time control and operation software was developed for the electro-hydraulic CVT system. By using the software and the CVT map, the control system was designed for the CVT speed ratio control with various drive modes. The electro-hydraulic CVT system developed in this study showed that the optimal operation algorithm could be obtained for the best fuel economy or the maximum power mode.

• 오토저널
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• 제15권3호
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• pp.36-46
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• 1993

In CVT vehicle, the engine speed is completely decoupled from the vehicle speed within the range from maximum transmission ratio to minimum transmission ratio. This allows the engine to operate in optimal state(e.g. best fuel economy or maximum power mode.) In this study, the CVT control algorithm for optimal operation of engine is suggested. In order to implement the real time digital control of electro-hydraulic CVT system, a software called CVTCON has been developed. CVTCON also includes the CVT operation module, (2) system test module, (3) system control module and (4) data management module. By using the CVTCON and the electro-hydraulic CVT system, two modes of experiments were carried out: constant throttle opening mode and acceleration mode. From the experimental result, it was found that the algorithm suggested in this study showed optimal operation of the CVT system.