• 제목/요약/키워드: Assessment unit

검색결과 1,179건 처리시간 0.034초

PMU를 이용한 실시간 전기 동요 예측 (A Real-Time Generator Swing Prediction using Phasor Measurement Units)

  • 조기선;김회철;이기송;신중린
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 춘계학술대회 논문집 전력기술부문
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    • pp.92-94
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    • 2001
  • This paper investigated the real-time generator swing prediction by some researchers. And the first swing stability assessment based on EAC(Equal-Area Criterion) by using phasor measurement unit is proposed. Also we proposed the multi-swing prediction techniques, which is to estimate system parameters by using least square method / extrapolation with phasor measurement units. And the multi-swing prediction is performed with the estimated parameters. Future works are necessary to verify the proposed approaches in this paper.

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Evaluation and analytical approximation of Tuned Mass Damper performance in an earthquake environment

  • Tributsch, Alexander;Adam, Christoph
    • Smart Structures and Systems
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    • 제10권2호
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    • pp.155-179
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    • 2012
  • This paper aims at assessing the seismic performance of Tuned Mass Dampers (TMDs) based on sets of recorded ground motions. For the simplest configuration of a structure-TMD assembly, in a comprehensive study characteristic response quantities are derived and statistically evaluated. Optimal tuning of TMD parameters is discussed and evaluated. The response reduction by application of a TMD is quantified depending on the structural period, inherent damping of the stand-alone structure, and ratio of TMD mass to structural mass. The effect of detuning on the stroke of the TMD and on the structural response is assessed and quantified. It is verified that a TMD damping coefficient larger than the optimal one reduces the peak deflection of the TMD spring significantly, whereas the response reduction of the main structure remains almost unaffected. Analytical relations for quantifying the effect of a TMD are derived and subsequently evaluated. These relations allow the engineer in practice a fast and yet accurate assessment of the TMD performance.

Toxicogenomic Assessment of Drugs-Induced Hepatotoxicity

  • Park, Joon-Suk;Hwang, Jae-Woong;Lee, Yong-Soon;Hwang, Seung-Yong;Jung, Jin-Wook;Kang, Jong-Soo;Lee, Gyoung-Jae;Lee, Wan-Seon;Jeon, Ki-Seon;Kang, Kyung-Sun
    • 한국독성학회:학술대회논문집
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    • 한국독성학회 2003년도 춘계학술대회 논문집
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    • pp.48-49
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    • 2003
  • Toxicogenomics is a term that represents the merging of toxicology with novel genomics techniques. Microarray, which provides a revolutionary basis to perform global gene expression analyses and to decode biological pathways, has begun to have a major impact on many different fields of drug discovery and development. (omitted)

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중환자를 위한 근거중심 영양지원 (Evidence-based Nutritional Support in the Intensive Care Unit)

  • 이영희;위미숙
    • 중환자간호학회지
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    • 제3권1호
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    • pp.79-88
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    • 2010
  • Optimal nutrition serves to maintain normal organ function and to preserve body energy stores to guarantee survival during times of shortage of food. Adequate nutrition of intensive care unit (ICU) patients improves outcome, while malnutrition is strongly associated with increased morbidity and mortality rates among critically ill patients. Previously published researches showed that trials of nutritional support in critical illness rarely fulfill basic quality requirements. Nutrition support plays a vital role in the prevention and treatment of nutritional deficiencies in at-risk, critically ill patients. This paper reviewed the challenges in determining critically ill patients' nutrition requirements including nutrition assessment, determination of caloric requirements then providing them with adequate nutrition support while in the ICU with the guidelines published by Society of Critical Care Medicine and American Society for Parenteral and Enteral Nutrition. Nutrition support can be effectively enhanced by using the guidelines.

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머시닝센터 주축 고장예측에 관한 연구 (A Study on Diagnosis and Prognosis for Machining Center Main Spindle Unit)

  • 이태홍
    • 한국기계가공학회지
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    • 제15권4호
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    • pp.134-140
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    • 2016
  • Main Spindle System has effect on performance of machine tools and working quality as well as is required of high reliability. Especially, it takes great importance in producing automobiles which includes a large number of working processes. However, main spindle unit in Machine tools are often cases where damage occurs do not meet the design life due to driving in harsh environments. This is when excessive maintenance and repair of machine tools or for damage stability has resulted in huge economic losses. Therefore, this studying propose a method of accelerated life test for diagnosing and prognosis the state of life assessment main spindle system. Time status monitoring of diagnostic data - through the analysis of the frequency band signals were carried out inside the main spindle bearing condition monitoring and fault diagnosis.

새로운 품질보증(品質保證)을 위한 자동검사(自動檢査)데이터의 활용(活用)에 관(關)한 연구(硏究) (A Study on the use of Automotive Testing Data for Updating Quality Assurance Models)

  • 조재입
    • 품질경영학회지
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    • 제11권2호
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    • pp.25-31
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    • 1983
  • Often arrangement for effective product assessment and audit have not been completely satisfactory. The underlying reasons are: (a) The lack of early evidence of new unit quality. (b) The collection and processing of data. (c) Ineffective data analysis techniques. (d) The variability of information on which decision making is based. Because of the nature of the product the essential outputs from an affective QA organization would be: (a) Confirmation of new unit quality. (b) Detection of failures which are either epidemic or slowly degradatory. (c) Identification of failure cases. (d) Provision of management information at the right time to effect the necessary corrective action. The heart of an effective QA scheme is the acquisition and processing of data. With the advent of data processing for quality monitoring becomes feasible in an automotive testing environment. This paper shows how the method enables us to use Automotive Testing data for the cost benefits of QA management.

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자동차 전장제품의 무연솔더 적용기술 및 솔더 접합부 열화거동 (Degradation Behavior of Solder Joint and Implementation Technology for Lead-free Automotive Electronics)

  • 홍원식;오철민
    • Journal of Welding and Joining
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    • 제31권3호
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    • pp.22-30
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    • 2013
  • Due to ELV banning, automotive electronics cannot use four kinds of heavy metal element (Pb, Hg, Cd, $Cr^{6+}$) from 2016. Therefore, this study was focused on degradation characteristics of Sn-3.0Ag-0.5Cu Lead-free solder joint with OSP and ENIG finsh under various reliability assessment method, as like to thermal shock test and high temeprature/high humidity test with test duration for cabin electronics. Also, we compared bonding strength degradation to other advanced research results of electronic control unit for engine room because of difference service temperature with mount location in automotive. Whisker growth phenomenon and mitigation method which were essentially consideration items for Pb-free car electronics were examined. Conformal coating is a strong candidate for mitigating whisker growth in automotive electronics. Necessary condition to adapt Pb-free in car electronics was shown.

농촌지역에서의 농업 유기물 흐름의 평가 (Assessment of agricultural Organic Matter Flow in a Rural Area)

  • 김진수
    • 한국농공학회지
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    • 제42권5호
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    • pp.114-124
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    • 2000
  • The method to estimate agricultural organic matter flow on the regional scale was established and applied to a rural area in Chongwon-gun, Chungbok in 1996. The study area is of about 67$\textrm{km}^2$ and its population is about 7,000. The stocks and flows of organic matter are represented in dry weight per unit area and dry weight per unit area per year, respectively. the amount of inflow of organic matter indicates a possibility to cause environmental pollution. the amount of animal waste 767 kg/ha/yr account for 42 percent of total amount of organic waste 1,834 kg/ha/yr and therefore the environment in study area is greatly influenced by livestock. The decrease in recycling rate of animal waste form 100% to 70% has greatly increased the amount of disposal waste nearly twice, i.e., from 267 kg/ha/yr to 497kg/ha/yr . The results of this study demonstrate that appropriate animal population, increase in recycling of animal waste and preservation of agricultural land are necessary for environmental conservation of the study area.

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수돗물의 탄소 배출량 평가 (Carbon Emission Evaluation of Tap Water)

  • 김진근;전홍진
    • 상하수도학회지
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    • 제25권4호
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    • pp.511-517
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    • 2011
  • To evaluate carbon emission in water treatment processes, LCA (life cycle assessment) was applied to 8 multi-regional water treatment plants (WTPs) from intake to supply of tap water. Investigation of 8 WTPs revealed that average carbon emission for 1 $m^3$ of tap water was 221 g. Major carbon emission sources in water supply system were intake and supply processes. Meanwhile, mixing process was the main carbon emission source in unit water treatment processes. Carbon emission was proportional to the turbidity and COD of raw water. Intake of better raw water and minimization of energy consumption in unit processes are needed to reduce carbon emission in the WTPs. In addition, comparison of carbon emission among WTPs can be used as a parameter for optimization of operation and maintenance of water treatment processes.

초등학교 과학 수업에서 수업 컨설팅 모형의 적용 (The Application of the Instruction Consulting Model in Elementary Science Lesson)

  • 최선영;김지연
    • 한국초등과학교육학회지:초등과학교육
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    • 제29권2호
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    • pp.233-241
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    • 2010
  • The purpose of this study was to apply the instruction consulting model for elementary science lesson with novice teacher. In this study the PIE(Preparation, Implementation and Evaluation stage) instruction consulting model was used. This model was introduced and offered during the electromagnet unit for sixth graders. The results of this study were as follows. First, in the assessment of the teacher's satisfaction with the instruction consulting the client teacher was found to be very satisfied. Second, the inquiry and scientific achievement for the students of the client's class were to increase in the experimental group, which demonstrated a statistically significant difference. Given the above results, the instruction consulting applied with the PIE model for novice teachers, who desire to raise the success rate of the experiment for students in the electromagnet unit of the elementary science class, helped the teachers to teach the students.

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