• 제목/요약/키워드: Total Utility

검색결과 535건 처리시간 0.022초

복합화력발전설비와 지역난방설비가 연계된 종합열병합발전시스템의 일간 최적운전계획 수립 (A Daily Optimal Operation Scheduling of Total Cogeneration System Operating by Combined Heat Power Plant and District Heat Devices)

  • 정지훈;이종범
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 춘계학술대회 논문집 전력기술부문
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    • pp.183-186
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    • 2001
  • This paper describes the optimal operation scheduling of total cogeneration system which is interconnected with combined heat power plant of utility and district heat devices. The numerical modeling about the cogeneration system and the auxiliary thermal energy devices are established and simulation is carried out by LINDO program in order to minimize the operation cost under the national viewpoint. The results reveal that the established numerical modeling and the operation strategy can be effectively applied to the total cogeneration systems to reduce the energy cost.

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A New Assessment for the Total Harmonic Contributions at the Point of Common Coupling

  • Han, Jong-Hoon;Lee, Kyebyung;Song, Chong Suk;Jang, Gilsoo;Byeon, Gilsung;Park, Chang-Hyun
    • Journal of Electrical Engineering and Technology
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    • 제9권1호
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    • pp.6-14
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    • 2014
  • A new method to determine the total harmonic contributions of several customers and the utility at the point of common coupling is presented. The proposed method can quantify the individual harmonic impact of each suspicious harmonic source at the point of common coupling. The individual harmonic impact index is then used to assess the total harmonic contribution of each harmonic source. This index can be calculated by the results processed from instantaneous harmonic voltage and current phasor values. The results demonstrate the performance of the proposed method in terms of steady-state accuracy and response to time-varying operating conditions. The proposed index can be used for billing purposes to control harmonic distortion levels in power systems.

흉강경을 이용한 전폐절제술 (Thoracoscopic Pneumonectomy)

  • 성숙환
    • Journal of Chest Surgery
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    • 제27권9호
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    • pp.808-811
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    • 1994
  • We reported a successful right pneumonectomy using video assisted thoracoscopy for endobronchial tuberculosis. Thoracoscopic surgery has many advantages in spite of its technical difficulties. These advantages include good cosmetic effects, short hospital stay, decreased postoperative morbidity, and good postoperative pulmonary function.The patient was young unmarried female, and her right lung was nearly total obstructed by endobronchial tuberculous dissemination and secondary pulmonary infection. The procedure was a little complicated by inadequate placements of the thoracoscopic ports and 5cm length utility thoracotomy incision. Minimal pain killer was needed only two days after operation and scar of operative wound was very satisfying. Postoperative course was unusual and the patient was discharged 7 days after operation.

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UXO(Unexploded Ordnance) 탐지를 위한 자력탐사 기술 (Technique of magnetic survey for UXO discrimination)

  • 박인석;김현도;김진후
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2005년도 후기학술대회논문집
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    • pp.158-159
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    • 2005
  • The paper presents a method for location of subsurface UXOs. The approach utilities gradient interpretation techniques (analytic signal, horizontal gradient and Euler methods) to locate the objects. Then, linear least-squares technique, we obtain the magnetization location of the sources. We demonstrate the practical utility of the method using marine magnetic field data.

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다목적 유전 알고리듬을 이용한 혼합모델 조립라인의 최적 생산순서계획 (Mixed-Model Sequencing Using Genetic Algorithms with Multiple Evaluation Criteria)

  • 김연민;김영진
    • 산업공학
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    • 제13권2호
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    • pp.204-210
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    • 2000
  • This paper deals with the problem of mixed-model sequencing on an assembly line. In this sequencing problem we want to minimize the risk of the conveyor stoppage and the total utility work. This paper applies genetic algorithm to solve the mixed-model sequencing problem which is formulated as an integer programming. The solution we get from this algorithm is compared with the solution of Tsai(1995)'s.

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수자원사업 대안선정 및 투자우선순위결정을 위한 다기준의사결정모형 개발 (Development of MCDM for the Selection of Preferable Alternative and Determination of Investment Priority in Water Resource Projects)

  • 여규동;김길호;이상원;최승안
    • 대한토목학회논문집
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    • 제31권6B호
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    • pp.551-563
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    • 2011
  • 수자원사업은 대규모의 예산이 투입된다. 따라서 수자원사업은 합리적이고 신뢰성 있는 의사결정이 필요한데 그동안 주로 경제성분석에 의존하여 왔다. 본 연구목적은 경제성분석위주의 기존 의사결정이 아닌, 사업의 필요성과 투자의 타당성을 다양한 각도로 평가할 수 있는 수자원사업 대안선정과 투자우선순위결정을 위한 다기준의사결정방법을 도출하는 것이다. 본 논문은 경제성 분석, 정책적 분석, 취약성 분석과 각각의 하위평가항목으로 평가기준을 구성하였다. 또한, 전문가 설문을 통한 사전 가중치를 제시함으로써, 일관성 있는 평가가 이루어지도록 하였다. 그리고 전문가 설문을 통해 평가항목의 속성별로 위험성향을 고려한 효용함수를 도출하였다. 종합평가점수는 평가항목별 가중치와 속성별 효용점수로 산정된다. 적용결과, 평가기준은 취약성 기준에 큰 영향을 받는 것으로 나타났다. 본 연구는 수자원사업에 대한 효율성과 취약지역에 대한 형평성을 제고하는데 기여할 수 있을 것으로 판단된다.

특1급 호텔 조리사의 푸드 스타일링 수행현황에 따른 메뉴개발 인식 및 활용속성 (Recognition and Utility Properties of Menu Development Derived from the Performance of Food Styling for Cooks in a Super Deluxe Hotel)

  • 천덕상;김병희;강근옥
    • 동아시아식생활학회지
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    • 제21권5호
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    • pp.771-778
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    • 2011
  • This study surveyed the performance of food styling and recognition and utility properties of menu development for cooks in a super deluxe hotel. The questionnaires developed for this study were distributed to 400 males and females aged 20 and over. A total of 375 questionnaires were used for analysis (93.8%), and statistical analysis was completed using SPSS (version 14.0) for descriptive analysis and ${\chi}^2$-test. The most important item in food styling was 'harmony of food shape' (40.2%), and second ranked was 'harmony of food color' (23.4%). The most difficult item in food styling was 'lack of professional knowledge' (38.3%) followed by 'lack of creativity' (27.7%). In recognition of menu development, the importance of menu development and promotion was 3.82, and personal satisfaction after menu development was 3.29. Important items in menu development were 'taste' (41.8%) and 'use of new ingredient' (28.5%). When using newly developed menu, the ratio of selling new menu was '30~50%' at 42.7%, and the average selling period of new menu was '3~6 months' at 40.5%. For the effect of new menu on sales, 94.1% were aware of this effect, and to actively promote menu development, 'providing incentive' (35.7%), 'training in/out of country' (20.8%), 'self motivation' (17.3%), 'financial support' (14.7%), and 'motive' (11.5%) were all necessary requirements. In order to improve cooking performance, continued education on food styling and menu development along with the company's full support are required. Further, thorough training of employees is needed along with a high quality incentive policy needs to be done. In addition, to make the new menu profitable, an active marketing strategy must be employed, which will require further study.

한의학 관련 이미지 연구 (The Research about Image on Korean Medicine)

  • 김재익;명예슬;안수연;이영지;조충식
    • 대한한방내과학회지
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    • 제35권3호
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    • pp.354-365
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    • 2014
  • Objectives: Recently, the utility rate of Korean-Medical service has been a 6 percent of the domestic market share in medical service, so there is a lot of effort to increase utility rate of Korean medical service. However, in spite of the importance of image to promotion, there are still few studies about image of Korean medicine. Thus, the purpose of this study was to suggest ways to increase utility rate of Korean medical service by surveying and analysing recognition of image of Korean Medicine. Methods: People aged between 20s and 40s were targets of investigation. We divided respondents into three groups depending on relation approximation with Korean medicine (weak-related group, normal-related group, strong-related group). The questionnaire consisted of questions about images of Korean medicine, conducted through online and personal interviews. Results: In total, 282 members responded to the survey and the results of the analysis were as follows. The more a person was related to Korean medicine, the greater the tendency to experience Korean medical service. The most associated taste about Korean medical institutions was Bitterness, smell was smell of Korean medicine, color was yellow, feeling was warm, sound (instrument) was drum, and treatment pattern was Acupuncture, respectively. The most associated image of acupuncture was painful, and the most associated age of Korean medical doctors was 40s. The most associated general term of Korean medicine was physical constitution, and most associated pathological term was extravasated blood. Conclusions: This study can be very useful for future image marketing of Korean medicine because there have been no other studies about image on Korean medicine before now. But this study has also some limits like area, respondent selection, etc., so a more detailed and comprehensive survey is needed.

Adaptive Cross-Layer Resource Optimization in Heterogeneous Wireless Networks with Multi-Homing User Equipments

  • Wu, Weihua;Yang, Qinghai;Li, Bingbing;Kwak, Kyung Sup
    • Journal of Communications and Networks
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    • 제18권5호
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    • pp.784-795
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    • 2016
  • In this paper, we investigate the resource allocation problem in time-varying heterogeneous wireless networks (HetNet) with multi-homing user equipments (UE). The stochastic optimization model is employed to maximize the network utility, which is defined as the difference between the HetNet's throughput and the total energy consumption cost. In harmony with the hierarchical architecture of HetNet, the problem of stochastic optimization of resource allocation is decomposed into two subproblems by the Lyapunov optimization theory, associated with the flow control in transport layer and the power allocation in physical (PHY) layer, respectively. For avoiding the signaling overhead, outdated dynamic information, and scalability issues, the distributed resource allocation method is developed for solving the two subproblems based on the primal-dual decomposition theory. After that, the adaptive resource allocation algorithm is developed to accommodate the timevarying wireless network only according to the current network state information, i.e. the queue state information (QSI) at radio access networks (RAN) and the channel state information (CSI) of RANs-UE links. The tradeoff between network utility and delay is derived, where the increase of delay is approximately linear in V and the increase of network utility is at the speed of 1/V with a control parameter V. Extensive simulations are presented to show the effectiveness of our proposed scheme.

시뮬레이션 모형을 통한 관광정보서비스 효과 분석 (Analysis of Tour Information Services using Agent-based Simulation)

  • 김현명;오준석
    • 대한교통학회지
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    • 제24권6호
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    • pp.103-117
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    • 2006
  • 본 연구에서는 개별 관광객을 Simulation하는 모형을 개발하고. 이를 이용해 첨단 관광정보시스템 하에서의 여행객의 관광지 선택행태 변화와 관광 수요 패턴의 변화를 분석하였다. 관광객의 여행계획 목적함수는 기대효용 최대화로 가정하였고, 교통망에서 순차적 방문 계획 해를 얻기 위해 Traveling Salesman Problem(TSP)을 이용하였다. 단 관광객들의 경우 하루 동안 주어진 여행시간과 여행예산의 제약이 존재하기 때문에, 제약이 존재하는 TSP. 즉 Prize-Collecting TSP를 이용하였으며, 하루 이상 관광지에 체류하는 관광객들의 여행계획 문제를 풀기위해 Prize-Collecting Multiple-Day TTaveling Salesman Problem(PC MD TSP)을 개발하였다 관광 정보의 형태는 사전정보, Oft-line 정보. On-line 정보로 구분하여, 전체 관광객들을 이용 가능한 정보 형태에 따라 3가지 계층으로 구분하였으며. Simulation을 통해 각 관광지의 관광객을 계산하였다. 개발된 모형을 통해 Ubiquitous 환경에서의 On-line 정보가 관광객들뿐만 아니라 관광지에도 수요증가에 따른 운영 이익 증대를 가져다 줄 수 있음을 확인하였다.