• 제목/요약/키워드: specific performance

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온도와 질량유속이 불화중수소 화학 레이저 성능에 미치는 영향 (Effects of Temperature and Mass Flux on Deuterium Fluoride Chemical Laser Performance)

  • 박병서;이정환
    • 한국군사과학기술학회지
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    • 제7권4호
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    • pp.100-106
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    • 2004
  • The effects of adiabatic flame temperature and mass flux on deuterium fluoride(DF) chemical laser performance were investigated. The power flux and specific power, which are important parameters containing the information of scaling effects of laser device magnitude, and chemical efficiency were selected as a judging parameter of DF laser performance. For the specific power, it was decreased by the increase of power flux of DF laser. Higher the adiabatic flame temperature of atomic fluorine generator, higher the chemical efficiency of DF laser was changed. It seems that the mass flux effect on the chemical efficiency is not remarkable.

고온 태양열 화학 반응기의 열전달 성능 분석 (Analysis of Heat Transfer Performance for a Solar Chemical Reactor)

  • 정영국;이주한;서태범
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2009년도 춘계학술발표대회 논문집
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    • pp.55-60
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    • 2009
  • The purpose of the research is to develop the high performance solar chemical reactor for producing hydrogen using steam reforming reaction of methane. A specific shape chemical reactor is suggested: spiral type reactor. The reactor is installed on the dish-type solar thermal system of Inha University. The temperatures, $CH_4$ conversion rates are measured. At specific condition, $CH_4$ conversion rates of the spiral type reactor are about 92%. The spiral type reactor gives reasonably good performance without any problems caused by highly concentrated solar radiation.

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노즐 외기 압력 변화에 따른 고체추진기관 성능 변화 연구 (A Study on Performance Change of Solid Rocket Motor for Variation of Nozzle Ambient Pressure)

  • 권태훈;노태호;조인현
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2007년도 제29회 추계학술대회논문집
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    • pp.219-222
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    • 2007
  • 본 연구에서는 노즐 외기 압력 변화에 따른 KSLV-I 2단 고체추진기관의 성능 분석을 수행하였다. 2단 고체추진기관은 고도 약 300km 상공에서 연소를 할 예정이다. 모터의 성능 검증을 위해 대기 압력 환경에서 연소시험을 수행하였다. 그리고, 환경 시험 설비를 적용하여 진공환경의 모터 성능 검증을 진행하였다. 지상 및 진공환경에서의 모터 비추력 변화를 통해 노즐 외기 압력이 고체추진기관의 성능에 미치는 영향을 분석하였다.

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정량적 인적오류 분석에서 수행도형성인자를 고려하기 위한 방법 (A Method for Considering Performance Shaping Factors in Quantitative Human Error Analysis)

  • 정광태
    • 한국안전학회지
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    • 제12권1호
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    • pp.113-121
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    • 1997
  • Human reliability attempts to make precise quantitative analyses and predictions of the performance of human-machine(or product) systems. In order to yield more precise human error analysis, precise human error probabilities(HEPs) must be used in the analysis. However, because human behavior is influenced by factors that are called performance shaping factors(PSFs), the effects of PSFs must be considered to obtain precise HEPs, These are called basic HEPs or situation-specific HEPs. This paper presents a theoretical method for obtaining basic HEPs (i.e. , considering PSFs) in quantitative human error analysis. In this method, the weight which characterizes the degree of importance of several PSFs is obtained by the analytic hierarchy process. The quality scores of PSFs in the task situation are obtained by percentile concept. These scores are used in conjunction with the relative Importance weights of PSFs to compute the composite quality percentile score of PSFs in the task situation. Then, a new mapping method of the composite quality percentile score of PSFs into a situation-specific basic HEP is proposed with a numerical example.

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비속도 150급 수직배럴형 다단 원심펌프 개발 (Development of Vertical Barrel Type Multistage Pump)

  • 유일수;박무룡;황순찬;김성기;윤의수
    • 한국유체기계학회 논문집
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    • 제15권1호
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    • pp.13-20
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    • 2012
  • A vertical-axis multistage pump with low specific speed was developed, satisfying performance requirements such as flow rate, total head, and NPSH. The developed pump was designed through conceptual design, configuration design, and performance analysis by CFD which were established in KIMM. The prototype pump's mechanical wholesomeness besides hydraulic performances were verified by running test, performance test, and reliability test.

물체 변형 성능을 향상하기 위한 U-net 및 Residual 기반의 Cycle-GAN (U-net and Residual-based Cycle-GAN for Improving Object Transfiguration Performance)

  • 김세운;박광현
    • 로봇학회논문지
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    • 제13권1호
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    • pp.1-7
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    • 2018
  • The image-to-image translation is one of the deep learning applications using image data. In this paper, we aim at improving the performance of object transfiguration which transforms a specific object in an image into another specific object. For object transfiguration, it is required to transform only the target object and maintain background images. In the existing results, however, it is observed that other parts in the image are also transformed. In this paper, we have focused on the structure of artificial neural networks that are frequently used in the existing methods and have improved the performance by adding constraints to the exiting structure. We also propose the advanced structure that combines the existing structures to maintain their advantages and complement their drawbacks. The effectiveness of the proposed methods are shown in experimental results.

정보기술 발전에 의한 관계 기반 고객 만족도 개발을 위한 연구 (Relationship Based Customer Satisfaction by the Development of Information Technology in Sports Industry)

  • 염지환
    • Journal of Information Technology Applications and Management
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    • 제20권4호
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    • pp.207-219
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    • 2013
  • The study examined relational marketing in terms of transaction specific satisfaction and cumulative satisfaction in the professional sport industry. The study evaluated the motivation of spectators visiting professional baseball games in 2012 and the satisfaction factors of relationship marketing. In this study, the satisfactions were considered in terms of single satisfaction associated with transaction and gradual satisfaction associated with customer loyalty. The relationship marketing was established considering each factor of marketing strategies, facility, game performance and entertainment. The study categorized the factors for customers to visit games as facility, game performance and entertainment with marketing strategies. The study found out that the customer satisfaction was related with both transaction specific satisfaction and cumulative satisfaction where cumulative one is longer term related. Moreover, cumulative satisfaction will be more related with the long term team financial performance.

섬유길이에 따른 비정질 강섬유 보강 시멘트 복합체의 충격파괴특성 (Impact Fracture Properties of Amorphous Metallic Fiber Reinforced Cementitious Composite by Fiber Length)

  • 이상규;김규용;황의철;손민재;편수정;남정수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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    • pp.65-66
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    • 2019
  • In this study, flexural strength and impact resistance were evaluated to investigate the fiber length effect of amorphous metallic fiber. As a result, in the case of 30AFRCC, cutoff behavior due to excellent bonding performance by large specific surface area has greatly influence on the flexural and impact resistance performance. In the case of 15AFRCC, the bonding efficiency is relatively low, because the specific surface area is smaller than that of 30AFRCC and the number of fiber is large, so the effect of improving the flexural and impact resistance performance is smaller than that of 30AFRCC.

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SI 엔진에서 바이오에탄올 연료(E100)의 연소 및 배기특성 (Combustion and Exhaust Emission Characteristics of Bio-Ethanol Fuel(E100) in SI Engine)

  • 하성용;이창식
    • 대한기계학회논문집B
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    • 제32권8호
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    • pp.582-588
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    • 2008
  • An experimental investigation was conducted to investigate the effect of Bio-ethanol fuel on the engine performance and exhaust emission characteristics under various engine operating conditions. To investigate the effect of bio-ethanol fuel, the commercial 1.6L SI engine equipped with 4 cylinder was tested on EC dynamometer. The engine performance including brake torque, brake specific fuel consumption, and barke specific energy consumption of bio-ethanol fuel was compared to those obtained by pure gasoline. Furthermore, the exhaust emissions were analyzed in terms of regulated exhaust emissions such as unburned hydrocarbon, oxides of nitrogen, and carbon monoxide.Result of this work shows that the effect of blending of ethanol to gasoline caused drastic decrease of emissions under various operating conditions. Also, improved engine performance such as brake torque and brake power were indicated for bio-ethanol fuel.

The Motivating Role of Sentiment in ESG Performance: Evidence from Japanese Companies

  • Vuong, Ngoc Bao;Suzuki, Yoshihisa
    • East Asian Economic Review
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    • 제25권2호
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    • pp.125-150
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    • 2021
  • The paper investigates investor sentiment's role in boosting Japanese companies to enhance their environmental, social, and corporate governance (ESG) performance. Using ESG scores of 367 firms between 2005 and 2019 from the ASSET4 database, we find that negative sentiment in the previous year, both firm and market level, can be a stimulation for the company's commitments to its ESG activities next year. Notably, the moderating effect of the business sector and economic cycle on the sentiment-ESG inference are detected in our study differentiating between corporate and market sentiment, which have never been reported before. In detail, we discover that the impact of firm-specific sentiment is less pronounced for high-sensitive ESG firms. On the other hand, the driving force of market sentiment on corporate social behaviors weakens when economic recessions happen. Our results are robust after controlling for potential endogeneity issues and using alternative proxies for market sentiment.