• 제목/요약/키워드: Usefulness index

검색결과 373건 처리시간 0.025초

변압기 용량을 고려한 수용률 산출 시뮬레이터 개발에 관한 연구 (A Study on Simulator for Computing Demand Rate Considering a Transformer Capacity)

  • 김영일
    • 전기학회논문지P
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    • 제56권4호
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    • pp.179-185
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    • 2007
  • In this paper, the method of computing demand rate with respect to a transformer capacity is proposed and addressed to predict a future demand rate. The simulation data are taken from switchgears of a real medium voltage transformer. Data taken from the electrical instrument at 22.9 kVY power receiving panels are employed to evaluate the correlation between demand rate and power usage of transformer. It is verified a usefulness with respect to an proposed index of demand rate for transformer by using a least square error of regressive modeling, As a result of investigation and simulation on the spot to a few buildings, it is considered that there is necessity to make a partial amendment of demand rate being applicable currently for electrical energy saving in domestic.

기업분할의 장기성과에 대한 실증연구 (The Corporate Spinoffs and Long-run Stock Returns)

  • 홍동현;이덕훈;황재호
    • 경영과정보연구
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    • 제25권
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    • pp.83-114
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    • 2008
  • We examine whether spinoffs improve long-run stock returns and analyze the factors of long run stock returns. The measures of long run stock returns are CAR(Cumulative Abnormal Returns) and BHAR(Buy and Hold Abnormal Returns). The expected factors of abnormal returns are methods of spinoffs, size, BV/MV, administrative costs, cashflow and Herfindahl index. We find that long-run returns of the case such as carve-out methods, small size, high BV/MV, low administrative costs, low cashflow and low Herfindahl index are larger than those of other cases. We show positive relationship between spinoffs and long-run stock returns(CAR and BHAR). The results supports spinoffs, as the methods of focusing on core business, are very usefulness of corporate restructuring.

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지능형 전기품질 평가모델 개발 (Development of Intelligence Electric Power Quality Assessment Model)

  • 이범;최남섭;김경민
    • 제어로봇시스템학회논문지
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    • 제13권6호
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    • pp.531-536
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    • 2007
  • This paper presents a power quality assessment model based on the Analytic hierarchy process. This model can assess unified power quality index which provide an overall performance of the distribution system. To obtain the unified power quality index, we propose the use of the AHP model which has three states: [Ideal]-[Actual]-[Worst]. The proposed method is especially useful and effective for planning. We have applied the proposed method to an actual relatively large system, and verified the usefulness.

온돌 온열환경지표 평가방법 (Evaluation Methods on ONDOL Thermal Environmental Index)

  • 김성조
    • 한국산업융합학회 논문집
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    • 제25권1호
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    • pp.101-110
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    • 2022
  • For this purpose, the authors proposed and proved usefulness of the modified mean skin temperature which is integrated mean radiation temperature and the effect of floor contacted heat conduction. The mean radiation temperature is applied form factor between half cross-legged human body and surrounding wall of indoor. In addition the floor contacted heat conduction is applied heat transfer coefficient of half cross-legged human body. Eight Korean young men were targeted for the experiment. From the experiment the authors excerpted physiological reaction and psychological reaction in Ondol environment which is combined physiccal environmental factor of artificial climate chamber, air and floor temperature. As a result of the experiment it is confirmed that heat conduction has more impact than heat exchange from existing research for the heat exchange between half cross-legged human body and surrounding wall in Ondol thermal environment. Thereby, it is proved the effectiveness of the modified mean skin temperature which is added floor contacted temperature to the Ondol thermal environmental evaluation index.

시간경로 유전자 발현자료에서 패턴일치지수와 적응 최근접 이웃을 활용한 결측값 대치법 (Missing values imputation for time course gene expression data using the pattern consistency index adaptive nearest neighbors)

  • 신혜서;김동재
    • 응용통계연구
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    • 제33권3호
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    • pp.269-280
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    • 2020
  • 시간경로 유전자 발현 자료는 마이크로어레이 실험을 시간에 따라 관측한 대용량의 자료로 유전자 발현 수준을 동시에 파악할 수 있다. 하지만 실험 과정이 복잡하여 다양한 원인들에 의해 결측값이 자주 발생한다. 본 논문에서는 시간경로 유전자 발현 자료에 대한 결측값을 추정하는 방법으로 패턴 적응 최근접 이웃(pattern consistency index adaptive nearest neighbors; PANN) 방법을 제안하였다. 이 방법은 국소적 특징을 반영하는 적응 최근접 이웃(adaptive nearest neighbors; ANN) 방법과 관측 시점간 유전자 발현의 일치 정도를 고려하는 패턴일치지수를 결합시킨 것이다. 제안한 PANN 방법의 효능을 평가하기 위하여 두 가지의 실제 시간경로 자료들을 사용하여 몬테카를로 모의실험(Monte Carlo simulation study)을 시행하였다.

프린터의 음질 인덱스 제작과 음질개선에 대한 응용 (Design of Sound Quality Index for Laser Printers and Its Application for Improvement Study)

  • 김의열;이영준;이상권
    • 한국소음진동공학회논문집
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    • 제22권6호
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    • pp.509-523
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    • 2012
  • The sound quality based on design optimization, throughout the development process of various electronic office equipments, needs to be considered in order to respond the increased needs for the emotional satisfaction of customers in terms of psycho-acoustics. This paper focuses on how to describe the characteristics of operating sound radiated from laser printers by using various sound attributes, and to model the sound quality index that can properly evaluate the subjective preference on modification conditions in the improvement study quantitatively. Especially, the proposed verification process, in the form of combining the correlation based method and the decision error based method, was applied to improve the generality and reliability of a group of participants in the jury evaluation. The modified Aures tonality model was also proposed to improve the correlation coefficient with the mean response of participants by optimizing some parameters. As a result, the loudness, articulation index, roughness, tonality, fluctuation strength were used to model the sound quality index for laser printers by using the multiple-linear regression method. Through the improvement study, it was confirmed that replacing the absorbing materials is effective to reduce the tonalness radiated from the side of a reference printer model. Based on above results, it can be concluded that the proposed model has enough usefulness as quantitative evaluation index to evaluate the difference between modification conditions in the improvement study.

청주시 무심천 주변의 열환경 특성 분석 (Analysis of Thermal Characteristics for Areas of Musim Stream in Cheongju City)

  • 박진기;나상일;박종화
    • 농업과학연구
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    • 제37권1호
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    • pp.81-86
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    • 2010
  • The urban thermal environment can be an important index to detect heat island phenomena and manage it to improve urban life quality. Cheongju is a typical plain-city that main part has been formed and developed in lowland. The Mushim stream crosses the city from south to north. We reviewed the use of thermal remote sensing in stream around areas and the thermal environments, focusing primarily on the Urban Heat Island(UHI) effect. The purpose of this study is to determine the relationship between the stream nearby urban area and the stream cooling effect of UHI. The objectives are to determine the usefulness of KOMPSAT-2 bands MS3 and MS4 for vegetation cover mapping, and the usefulness of LANDSAT TM band 6 in identifying thermal environmental characteristics and UHI. Land Surface Temperatures (LST) are retrieved by single-channel algorithm to study the UHI from the 6th band (thermal infrared band) of LANDSAT TM images and thermal radiance thermometer based on remote sensing method and the LST distribution maps are accomplished according to the retrieval results. There is also comparison of satellite-derived and in situ measured temperature. The results indicated that the LST of urban center is higher than that of suburban area, the temperature of mountain and water are the lowest area, so it is clearly proved that there are obvious UHI effects by stream. The surface temperature distribution of Mushim stream is detected $2^{\circ}C$ lower than urban area.

공간구조분석을 위한 시뮬레이션 추적 분석에 관한 연구 (A Study on Simulation tracking analysis for Spatial configuration analysis)

  • 박종현;이종렬
    • 한국디지털건축인테리어학회논문집
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    • 제9권3호
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    • pp.95-102
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    • 2009
  • An architectural space can be considered a life form that interconnects a number of architectural elements such as the humans who live in it. It is difficult to understand and evaluate the complexity of the interrelation between each element, but there have been various attempts to understand and evaluate this architectural space. The Space Syntax that emerged in 1980s has been studied and used more frequently than other methods. Space Syntax is the space analysis tool that analyzes the physical structure of space and represents it as a graph. Space syntax enables its various applications in space analysis by quantifying each spatial property of a whole structure, analyzing it systemically and objectively based on mathematical logic, and representing the results as a quantitative value. Integration of Space Syntax, a widely used index, reflects human behavior in spatial configuration. Meanwhile, there have been various studies in the field of architectural environmental psychology about the relationships between space and human behavior by applying behavioral science to architectural plan. One of the most widely used one is spatial behavior simulation which uses models and simulates the behavioral characteristics to anticipate practical situations and investigate the behavior related spatial problems. In this study, which focuses on the accessibility of the space syntax model, the usefulness of space will be analyzed through the simulation of human behavior that moves through each space. Furthermore, the validity of index will be verified by displaying several examples and compared with integration in space syntax, which represents the usefulness of space.

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만성질환자의 영양상태와 예후판정에 대한 간이영양평가 도구의 유용성 평가 -혈액투석환자를 중심으로- (Evaluation of Clinical Usefulness of Instant Nutritional Assessment Scale for the Nutritional Status and Prognosis of Hemodialysis Patients)

  • 송경애;김명자
    • 기본간호학회지
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    • 제4권2호
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    • pp.337-349
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    • 1997
  • The prognosis of maintenance hemodialysis (HD) patients is closely related to their nutritional status. It is important to develop and use of a reliable, useful and easy method of nutritional assessment scale for evaluation of nutritional status and progression of the patients. This study was initiated to evaluate the clinical usefulness of Instant Nutritional Assessment Scale(INAS) by cross-sectional and longitudinal studies. One hundred HD patients entered a continuing nutritional study and followed for 1 year. The results were as follow ; 1. 24% of patients was normal to mild, 43% was moderate and 33% was severe deficit of nutritional status. 2. The mean INAS score of the patients was 8.00(S. D.=2.83), and there didn't reveal any differences in INAS score by general characteristics. The mean transferrin score was 1.98, whih was the highest of 5 nutirtional parameters of INAS. Only 7 patients had within nomal range of transferrin concentration. 3. Within one year since this study was initiated, 10 patients died. Six of them were with severe deficit and one of them was normal to mild deficit groups. The death rate in severe deficit group was higher than that of normal to mild deficit group (P=.0640). 4. Occurrence of acute complication during HD in severe deficit guoup was higher than that of normal to mild deficit group(P=.001). 5. The number of consultation to the doctor and hospital admission in severe deficit group was higher than that of normal to mild deficit group(P=.0001). 6. INAS score was significantly correlated with occurrence of acute complications during HD and the number of consultation to the doctor. In conclusion, INAS based on the levels of body mass index, midarm circumference, triceps skinfold thickness, transferrin concentration and total lymphocyte count seems to be a reliable predictive nutritional index for prognosis. So nurses are encouraged to adopt INAS in care of the chronically illed patients. Recommendations for further research was suggested.

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