• 제목/요약/키워드: System Utilization

검색결과 5,011건 처리시간 0.036초

Enhancement of the energy efficiency of hydrogen SOFC system by integrated cold energy utilization and waste heat recovery method

  • Nguyen Quoc Huy;Duong Phan Anh;Ryu Bo Rim;Lee Jin Uk;Kang Ho Keun
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2022년도 추계학술대회
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    • pp.160-161
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    • 2022
  • Hydrogen is bridge fuel with high energy content and environmentally friendly to satisfy the stringent IMO regulation relating to greenhouse gas (GHG) emissions. There is growing interest in hydrogen in numerous nations and regions illustrated by an extensive range of research and development in technology. Regarding maritime applications, researchers have recognized the utilization of hydrogen as a fuel for fuel cells, a device that converts the chemical energy of the fuel to electrical energy. Solid oxide fuel cell (SOFC), with high working temperature, is easy to combine with the waste heat recovery cycles/devices to increase output power and thermodynamic performances as well. Furthermore, the cold energy from liquid hydrogen supplied to SOFC can also be used to generate more power. In this study, we proposed a SOFC integrated system with the idea of combining the waste heat recovery from the SOFC exhaust stream and cold energy utilization from LH2. The designation is aimed to target small-scale vessel which uses electric propulsion for short distances voyage.

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공유수면 인공구조물 설치에 따른 해역이용협의서 작성실태 평가 (Assessment of Documentation Status of the Statement on the Sea Area Utilization according to Artificial Structure Installation in Public Water)

  • 엄기혁;이대인;김귀영;윤성순
    • 환경영향평가
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    • 제22권3호
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    • pp.265-276
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    • 2013
  • This study assessed documentation status of each environmental assessment items by analyzing the 243 case of marine EIS on the Consultation System of Sea Area Utilization. Observed rate of tidal elevation, current, temperature, salinity in maine environment were below 20%. The EFDC tool is applied substantially in hydrodynamic modeling. The verification process, however, is very insufficient using the recent observed data. Also, in-situ assessment rate of pelagic organism such as phytoplankton was below 50%, and assessment for Chlorophyll a was not accomplished. Ecological index evaluation for zooplankton and benthic ecosystem were not considered in statements. Especially, the rational assessment on the fisheries resources and protected species were very limited. It was necessary that the core assessment items (checklists) were established for environmental scoping. Furthermore, suggestion of information related to development, regional coastal management plan, aquaculture farms, and facilities were enhanced. The redundancy problem of proceedings between Environmental Impact Assessment and Sea Area Utilization Assessment System was improved.

철도 변전소 공유를 통한 직류 도시철도 시스템 회생에너지 이용률 향상 방안 연구 (A Study of Improving Regenerative Energy Utilization in Urban DC Railway Systems Through Sharing Substations)

  • 정승민;이한상;변길성;권세혁;장길수;정호성;김형철
    • 전기학회논문지
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    • 제60권12호
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    • pp.2392-2396
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    • 2011
  • This paper deals with the power integration of large urban railway systems to improve regenerative energy utilization. Current regenerative energy utilization is low because there is no special plan for using this energy. If the railway system is integrated with other railway systems, the efficiency is expected to be improved. Through the case studies, to find the realistic effect of integrated operation, real system for the Seoul Metro lines, especially line 5 and 7, had been applied.

A DESIGN OF SMALL DATA UTILIZATION SYSTEM FORTHECOMS

  • Seo Seok-Bae;Ku In-Hoi;Kang Chi-Ho;Lirn Hyun-Su;Ahn Sang-IL
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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    • pp.268-271
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    • 2005
  • COMS (Communication, Ocean, and Meteorological Satellite) will be launch at end of year 2008. For receiving of COMS LRlT, KARl (Korea Aerospace Research Institute) finished design and software realization of COMS SDUS (Small Data Utilization System). SDUS is a small station receiving LRlT data for distribute satellite image, weather information, and so on. For the future project, KARl preparing COMS MDUS (Mass Data Utilization System) that can receiving large size of data over than 2M BPS (Bit Per Seconds) data size.

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Feedback Burst Loss Ratio Control for Link Performance Improvement in Optical Bur st Switching Networks

  • Linh, To Hoang;Yoon, Gwi-Ok;Nam, Jae-Hyun;Solongo, Ganbold;Hwang, Won-Joo
    • 한국멀티미디어학회논문지
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    • 제16권9호
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    • pp.1067-1076
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    • 2013
  • Known as an important criterion that evaluates performance of future high-speed backbone networks, burst data loss ratio is well-studied in Optical Burst Switching networks. Current literatures mostly focus on reduce burst loss ratio without considering the system stability and link utilization after reducing. In this paper, we propose a novel framework which comes from feedback theoretic to dynamically control burst loss ratio in OBS. The proposed scheme tries to track the pre-set values of burst loss ratio and increases the stability and link utilization degree. The simulation results show that measured burst loss ratio always tracks setup reference with small errors, wavelength channel utilization is increased up to 2% and the system stability is also improved.

HMM-based Adaptive Frequency-Hopping Cognitive Radio System to Reduce Interference Time and to Improve Throughput

  • Sohn, Sung-Hwan;Jang, Sung-Jeen;Kim, Jae-Moung
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제4권4호
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    • pp.475-490
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    • 2010
  • Cognitive Radio is an advanced enabling technology for the efficient utilization of vacant spectrum due to its ability to sense the spectrum environment. It is important to determine accurate spectrum utilization of the primary system in a cognitive radio environment. In order to define the spectrum utilization state, many CR systems use what is known as the quiet period (QP) method. However, even when using a QP, interference can occur. This causes reduced system throughput and contrary to the basic condition of cognitive radio. In order to reduce the interference time, a frequency-hopping algorithm is proposed here. Additionally, to complement the loss of throughput in the FH, a HMM-based channel prediction algorithm and a channel allocation algorithm is proposed. Simulations were conducted while varying several parameters. The findings show that the proposed algorithm outperforms conventional channel allocation algorithms.

Greenhouse Bulk 건조기에 의한 태양열이용에 관한 연구 (제2보) (Solar Energy Utilization in a Greenhouse Bulk Curing and Drying System. (II))

  • 이철환;변주섭
    • 한국연초학회지
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    • 제5권1호
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    • pp.79-85
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    • 1983
  • The greenhouse bulk curing and drying system utilization of the direct solar energy was tested to evaluate that how much fuel could be saved for curing flue-cured tobacco at the Dae Gu Experiment Station (North latitude : $35^{\circ}$49'), in 1979-1982. The air temperature and total radiation were 19.0 to 38.5$^{\circ}C$ and 1311.0 to 1412.7 cal/$\textrm{cm}^2$/day during the 4 replicated curing test, respectively. The greenhouse bulk curing and drying system was able to cut fuel consumption by 32% compared with the conventional bulk curing barn. We could obtain almost same utilization efficiency of solar energy in 1982 compare with normal year, mainly increasing the heat receiving area.

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실시간 시스템 개발을 위한 데이터 처리 시간과 프로세서 사용율 추정 기법 (An Estimation Scheme on Processing Time and Processor Utilization for Real-Time System Development)

  • 김한동;최태봉;고순주
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2005년도 한국컴퓨터종합학술대회 논문집 Vol.32 No.1 (A)
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    • pp.820-822
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    • 2005
  • The current paper is on a study of the performance estimation fer data processing time and CPU utilization to efficiently develop the real-time system. The analytical modeling and OPNET modeling and benchmarking tests are applied to perform the estimation for data processing time and CPU utilization in real-time system. We demonstrate that the estimation results can be predicted fairly and accurately through the benchmarking test results although there is a small variance between the estimation results and the benchmarking test results.

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근골격계질환자의 양.한방 외래 의료이용과 관련요인 (The Utilization of Western and Oriental Medical Services by Outpatients with Musculoskeletal System Disorders and Its Related Factors)

  • 김성영;박재용
    • 보건의료산업학회지
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    • 제6권1호
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    • pp.27-38
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    • 2012
  • This study is to find out the correlation among the predisposing, enabling, and need factors in Anderson Behavioral Model using the data from Korea Medical Panel Survey conducted in the early part (April 1 - October 31) of 2008. The findings are as follows. It was found that the utilization rate of western medical service was far higher. the influential factor to choose western or oriental medical service taking western medical institutions as the reference group, the influential factor to choose oriental medical institution has significantly increased when the patient who have covered by medical insurance has one accompanied disease and their age was between 45 - 74, compared to the people less than 45 years old. It also increased when the age of the patient was between 45-54 years old, and in the event those who are not covered by medical insurance have accompanied disease and that the disease mobility period is 2-4 years. reviewing the several characteristics of the utilization of western and oriental medical services by the patient with musculoskeletal system disorders, the number of accompanied disease is an influential factor for the utilization of oriental medical services. And, disease mobility period is a significant factor for the utilization of both western and oriental medical services together, though it is not identified in this study. Therefore, it is expected that mutual cooperation between western and oriental medical services is more required for the patient with musculoskeletal system disorders as the aging society rapidly develops. In order to foster oriental medicine, it is required to specialize in competitive disease such as musculoskeletal system disorders.

의료이용심사에 대한 소고 (Introduction to Utilization Review)

  • 신의철
    • 한국의료질향상학회지
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    • 제12권2호
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    • pp.75-83
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    • 2006
  • Background : Utilization review has been adopted as a vehicle for cost and utilization control of health care services. Its role was further stressed and expanded through the establishment of Health Insurance Review Agency in 2001. This article is to introduce concept, activities, and effect of utilization review based on the experiences of U.S. and to suggest important characteristics for ideal utilization review activities at the national level in Korea. Method : Twenty-five articles related with utilization review were reviewed after being selected through web site search through Med Line and Richis. Result : Utilization review was introduced mainly for health care expenditure control either by insurer, provider or the third parties under the pressure of increasing health care cost. It's activities can be categorized to prospective, concurrent and retrospective review according to the time of service provision. Based on most of studies, utilization review has been effective in controling rising health care cost and utilization. However it's effectiveness assumes a reimbursement structure of managed care like capitation payment. More worse, it is still unknown it's effectiveness on quality of care. Conclusion : Utilization review should be employed to increase the cost effectiveness of medical care by optimizing quality and patient's outcomes while also attempting to reduce the use of resources. So, it should consider outcomes before expenditures, check for both under and over-use, and construct an structure in which consumption is reduced equitably. Aggressive adoption of utilization review in Korean health care setting with fee-for-service reimbursement structure might not be a cost-effective approach before adoption of prospective payment system such as D.R.G. and capitation.

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