• 제목/요약/키워드: Stabilization Control

검색결과 1,253건 처리시간 0.028초

신재생에너지가 연계된 마이크로그리드에서 에너지 저장장치의 최적 용량 선정에 관한 연구 (A Study on Optimal Capacity of Energy Storage System in Renewable Energy Based Micorgrids)

  • 김욱원;이남형;이윤성;신제석;김진오
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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    • pp.529-533
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    • 2012
  • By introducing RPS(Renewable Portfolio Standard) for reduction of greenhouse gas, Renewable energy sources have becoming widespread gradually. However, Renewable energy sources, such as wind power and PV are difficult to control the output and they have intermittent characteristics of the output. These characteristics would cause some problems when it is connected in the power system. In order to solve these problems, Energy Storage Systems(ESS) are considered to use. Although there are many different storage devices, the utilization of Secondary Battery is the one of the best ways to stabilize an output fluctuation of RES because of its fast responsibility. For that reason, it would better fit a large-capacity of Secondary battery for stabilization. However, batteries cannot be installed with a large capacity blindly because of its expensive cost. So to select proper capacity of the battery is an important consideration. This paper presented a methodology for the optimal capacity and operation of ESS in microgrids.

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日本における 藥用植物の生産, 消費の 現況 (The Present Condition of Production and Consumption of Medicinal Plants in Japan)

  • Kawahara, Nobuo
    • 한국자원식물학회지
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    • 제6권1호
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    • pp.33-44
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    • 1993
  • The medicinal plants used traditional medicines are classified into two groups. The first group is formulary medicine which have been recorded on authorized books, for example, kampo drug in Japan. The second group is the fork medicines. These medicinal plants production is 165 billion yen(about 1.5 billion dollar) and which rate to to total pharmaceutical production is about 3% in 1990. The number of important medicinal plants treated in the market is 124 herbs from the total 364 herbs for kampo durgs(210 preparations kampo durgs) and other propritetary drugs (agents for common cold, laxatives, gastrointestional and so on). The production of the Ginseng and Bupleurum Root are increased about ten times in last twelve years(1976 or 1988). The 80% of these medicinal plants are imported from China, Korea and Southern Asian countries. Then the Pharmaceutical Affairs Bureau of Ministry of Health and Welfare published "The Guideline of Medicinal Plant for Cultivation" for a quality control and a stabilization supply of 80 herbs. The first part(1992) of the guideline reported 5 herbs; Coptis Rhizome, Rehmannia Root, Bupleur, Root, Japanese Angelica Root and Rhubarb, The next part will be published following 5herbs; Cnidium Rhizome, Safflower, Coix seed and Fruiet, Platicodon Root and Zedoary.

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터널의 품질관리를 위한 숏크리트 초기강도의 현장강도 시험기술 (Field Testing Methods on Early Shotcrete Strength for Tunnel Quality Control)

  • 홍의준;장석부;이성우;김기림;문상조
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 춘계학술대회 논문집
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    • pp.468-476
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    • 2007
  • Generally, the strength of the field shotcrete is heavily dependent on the field mixing and spraying conditions so that it is different from the strength of the shotcrete mixed in laboratories. As a support member, the early strength of shotcrete unlike concrete as structural material is very important to the initial stabilization of the excavation face in tunnels. Therefore, the field methods to efficiently test the early strength of shotcrete have been highly required. This paper aimed to verify the pneumatic pin penetration test and the point load test for measuring the early strength of the field shotcrete. Through a series of uniaxial compression, pin penetration, and point load tests for the range of the early shotcrete strength, two equations to estimate reliably the uniaxial compressive strength by the pin penetration and the point load tests were derived. Field tests in working tunnel were carried out in order to estimate the economic efficiency. As a result, pin penetration method was proved to be the most effective method for testing the early strength of the field shotcrete.

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레이저 유도 초음파를 이용한 재료평가 및 비파괴 검사 시스템 개발에 관한 연구 (The Study on the Material Evaluation and Development of Nondestructive Inspection System Using Laser Guided Ultrasonics)

  • 김재열;송경석;김창현;김유홍
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2004년도 추계학술대회 논문집
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    • pp.263-268
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    • 2004
  • In the present study, a Nd;YAG Laser (pulse type) was used to emit ultrasonic signals to a test material. In addition, a total ultrasonic investigation system was designed by adopting a Fabry-Perot interferometer, which receives ultrasonic signals without any contact. For non-destructive test SM45C, which contains some flaws was used as a test material. Because it is easy to align light beam in receiver, and the length of the light beam does not change much even if convex mirror leans towards one side, confocal Fabry-Perot interferometer, which has stable frequency, and PI control are used to correct interfered and unstable signals from temperature, fluctuation and time shift of laser frequency. Stable signals are always obtained by the feedback of PI circuit signals in the confocal Fabry-Perot interferometer. The type, size and position of flaws inside the test material were examined by achieving the stabilization of an interferometer. This study presented a useful method, which could quantitatively investigate the fault of objects by using a Fabry-Perot interferometer.

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각가속도를 이용한 이족 로봇의 동적 걸음새 구현 (Dynamic Gait embody using angular acceleration for a Walking Robot)

  • 박재문;박승엽;고봉진
    • 한국항행학회논문지
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    • 제11권2호
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    • pp.209-216
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    • 2007
  • 본 논문에서는 보행 로봇의 자세 안정화 및 동적 걸음새를 구현하였다. 10개의 RC 서보모터가 로봇 관절에 사용되었고, 각 로봇의 관절은 어떤 걸음새 동작에도 충분히 움직일 수 있게 하였다. 각 관절 궤적은 3차 스플라인 보간법에 의해 생성되며, 궤적의 안정성은 로봇 모델링에 의한 ZMP(Zero Moment Point)를 이용하여 입증하였다. 또한 복잡한 구조와 표현을 피하기 위해 각 가속도를 이용한 ZMP방법을 구현 하였고, 로봇의 안정 상태를 측정하기 위해 기울기 센서와 자이로 센서가 사용되었다. 10개의 서보모터 제어, 궤적 생성, ZMP 보상, 센서 측정 등 과 같은 대부분의 계산 과정은 DSP에서 이루어지며, PC에서는 단순히 로봇의 상태, 데이터 처리 등의 모니터링에 이용하였다.

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RCM을 이용한 디젤 분무거동 및 자발화 특성에 관한 연구 (An Experimental Study on Diesel Spray Dynamics and Auto-Ignition Characteristics in the Rapid Compression Machine)

  • 강필중;김형모;김용모;김세원
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 춘계학술대회논문집B
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    • pp.447-452
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    • 2000
  • The low-emission and high-performance diesel combustion is an important issue in the combustion research community. In order to understand the detailed diesel flame field involving the complex Physical Processes, It Is quite desirable to study diesel spray dynamics, auto-ignition and spray flame propagation. Dynamics of fuel spray is a crucial element for air-fuel mixture formation flame stabilization and pollutant formation. In the present study, the diesel RCM (Rapid Compression Machine) and the Electric Control injection system have been designed and developed to investigate the effects of injection Pressure, injection timing, and intake air temperature on spray dynamics and diesel combustion processes. In terms of the macroscopic spray combustion characteristics it is observed that the fuel jet atomization and the droplet breakup processes become much faster by increasing the injection pressure and the spray angle. With increasing the cylinder pressure there is a tendency that the shape of spray pattern in the downstream region tends to be spherical due to the increase of air density and the corresponding drag force. Effects of intake temperature and injection pressure on auto-ignition is experimently analysed and discussed in detail.

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도시 주부가 인지한 가계의 재정문제에 관한 연구 (A Study on Financial Problem of Family Perceived by Housewife in Urban Areas)

  • 이정우;정진희
    • 가족자원경영과 정책
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    • 제3권1호
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    • pp.51-65
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    • 1999
  • The purpose of this study is to structure finance management education programme and to provide basic data orienting finance service system by means of analyzing the level of financial problem and its influential variables. The following is the result of this study: First, the level of financial problem perceived by housewife in urban areas is in the following order ; property which is perceived the least. Second, the level of financial problem perceived by housewife in urban areas is dependant on housewife age, husband education level, husband occupation, the degree of property, the degree of debts, tendency of fortune control, tendency of materialism, feeling of appropriate resource. It is especially noting that housewife in forties shows high level of financial of financial problem recognition than housewife in twenties does. This indicates needs for middle for middle-aged home management in which happens house moving to larger size, education of children, marriage of children, preparation for stabilization basis after children’s marriage, and shortage of surplus money. Third, variables which affect all sub-areas are family property sum, tendency of materialism, feeding of appropriate resources. The less family property sum, the stronger tendency of materialism, and the more perceive feeling of appropriate resources, the more perceive they financial problems.

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익상견갑에 대한 전거근 운동: 증례 보고 1. (Serratus anterior muscle exercise for The Winging Scapula: Case Study)

  • 장준혁;구봉오;김선엽
    • 대한정형도수물리치료학회지
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    • 제9권2호
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    • pp.69-77
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    • 2003
  • Objective: The purpose of this study is to describe the effect of the serratus anterior muscle exercise in a patient with winging of the scapular. Background and Purpose: The patient was a 33-year-old man with an 3 years history of the left deltoid region. He had not responded to previous treatments of rest, TENS and medicine. Materials and Methods: After Surgical operation of the shoulder, the patient was treated for 6 months in 144 visits. treatment consisted of push-up with plus in the standing position with his hands against the wall and unique push-up with quadruped position at mat. Also, Sling exercise therapy was utilized to control scapular stabilization and reduce stress on the scapulohumeral joint. Result: Following 104 physical therapy visits, the patient was able to full range of motion of the shoulder without shrug motion. Conclusion and Discussion: Scapular winging and serratus anterior muscle function are important consider in the rehabilitation of the shoulder dysfunction. Therefore, specific exercise program for people with the winging scapular should be considered.

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Human Ribosomal Protein L18a Interacts with hnRNP E1

  • Han, Sun-Young;Choi, Mie-Young
    • Animal cells and systems
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    • 제12권3호
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    • pp.143-148
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    • 2008
  • Heterogeneous nuclear ribonucleoprotein E1(hnRNP E1) is one of the primary pre-mRNA binding proteins in human cells. It consists of 356 amino acid residues and harbors three hnRNP K homology(KH) domains that mediate RNA-binding. The hnRNP E1 protein was shown to play important roles in mRNA stabilization and translational control. In order to enhance our understanding of the cellular functions of hnRNP E1, we searched for interacting proteins through a yeast two-hybrid screening while using HeLa cDNA library as target. One of the cDNA clones was found to be human ribosomal protein L18a cDNA(GenBank accession number BC071920). We demonstrated in this study that human ribosomal protein L18a, a constituent of ribosomal protein large subunit, interacts specifically with hnRNP E1 in the yeast two-hybrid system. Such an interaction was observed for the first time in this study, and was also verified by biochemical assay.

골육세포 성장 촉진을 위한 스마트 써피스 텍스처링 임플란트 스템 제작 기술 (Smart Surface Texturing Implant Stem for Enhancement of Osteoblast Cell Biocompatibility)

  • 김경한;이제훈;박종권;진석원;최완해;이홍진
    • 한국정밀공학회지
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    • 제31권5호
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    • pp.375-380
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    • 2014
  • To enhance biocompatibility between the orthopedic implant stem and obsteoblast cells, bone-forming cells, micro-size holes are patterned in Ti plate surface. Initially, the house built laser power stabilization system is applied to the laser micro patterning machine to convince repeatable result. Various pulse widths are irradiated Ti plate and relationship between diameters of patterned holes and pulsed width is derived. Effect of multi pulse is observed and optimal pulse number is considered to avoid heat affected zone. After MG-63 osbeoblast cells are cultured, micro patterned Ti plates are compared with control plates. In SEM image, cells are well aligned and aggregation is observed in both 60, and $100{\mu}m$ patterned plates. Finally, free form surface stem model is prepared to test micro hole patterning.