• Title/Summary/Keyword: load priority

Search Result 207, Processing Time 0.024 seconds

A Study on the Optimal Operation of Fuel Cell in Power Systems (전력계통에 있어서 신에너지전원(연료전지)의 최적 운용방안에 관한 연구)

  • 노대석;홍승만;이은미
    • Proceedings of the KAIS Fall Conference
    • /
    • 2002.11a
    • /
    • pp.141-144
    • /
    • 2002
  • Recently, the operation of power distribution systems has become more difficult because the peak demand load is increasing continuously and the daily load factor is getting worse and worse. Also, the consideration of deregulation and global environment in electric power industry is required. In order to overcome these problems, a study on the planning and operation in distribution systems of dispersed generating sources such as fuel cell systems, photovoltaic systems and wind power systems has been performed energetically. This study presents a method for determining an optimal operation strategy of dispersed co-generating sources, especially fuel cell systems, in the case of both only electric power supply and thermal supply as well as electric power supply. In other words, the optimal operation of these sources can be determined easily by the principle of equal incremental fuel cost and the thermal merits is evaluated quantitatively through Kuhn-Tucker's optimal conditions. In order to select the optimal locations of those sources, an priority method using the comparison of total cost at the peak load time interval is also presented. The validity of the proposed algorithms is demonstrated using a model system.

Characteristics of Non-Point Pollutant Runoff in Highland Field Fields through Long-term Monitoring (장기 모니터링을 통한 고랭지 밭 지역의 비점오염물질 유출특성)

  • Lee, Su In;Shin, Jae Young;Shin, Min Hwan;Ju, So-Hui;Seo, Ji Yeon;Park, Woon Ji;Lee, Jae Young;Choi, Joong Dae
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.59 no.4
    • /
    • pp.85-96
    • /
    • 2017
  • In this research, I performed rainfall monitoring by selecting the spot which can represent high altitude cool farm region in recent 3 years, and tried to understand the characteristic of outflow of non-point pollutants coming from high altitude cool farm region. As a result, it was shown that reducing rainfall runoff in highland farm area can reduce non-point pollution load and should consider priority to reduce runoff through management resources when selecting abatement method. Additionally, it is judged that reduction method related to base run-off should be selected by performing research on material motion of TN.

A Case Study on the Acclimatization's Housing for Environmental Load Reduction (환경부하 저감을 위한 기후순응주거 사례연구)

  • Cho, Sung-Woo;Oh, Se-Gyu
    • Journal of the Korean housing association
    • /
    • v.24 no.6
    • /
    • pp.69-79
    • /
    • 2013
  • The concept of sustainable development to preserve natural environment through economy in resources and energy is gradually distinguished since environmental problems as a series of air pollution and global warming take place now. Building occupies more than 1/3 of energy consumption in the whole world. Energy consumption of buildings caused a quick increase in the amount of energy use by air conditioning, which has a lot of effects on exhaustion of fossil energy as well as an increase in environmental load. Therefore, this research intends to suggest characteristics and direction for the designing of acclimatization's housing through the case study on acclimatization's housing. Acclimatization's housing is designed to reduce building load from the designing stage unlike green home or low-energy apartment. Also, factors which are commonly applied to acclimatization's housing are applied complexly by design strategic factors of Heating, Cooling and Lighting. The applied design factors make effects mutually and complexly. In addition, design strategy showed different priority by designing direction.

A Study on the Optimal Planning for Dispersed Fuel Cell Generation Systems in Power Systems (전력계통에 있어서 분산형 연료전지 발전시스템의 최적 도입계획에 관한 연구)

  • Rho, Dae-Seok;Shim, Hun;Oh, Yong-Taek;Choi, Jae-Seok;Cha, Jun-Min
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.50 no.6
    • /
    • pp.265-274
    • /
    • 2001
  • Recently, the operation of power systems has become more difficult because the peak demand load is increasing continuously and the daily load factor is getting worse and worse. Also, the consideration of deregulation and global environment in electric power industry is required. In order to overcome those problems, a study on the planning and operation in power systems of dispersed generating sources such as fuel cell systems, photovoltaic systems and wind power systems, has been performed energetically. This paper presents a method for determining an optimal operation strategy of dispersed co-generating sources, especially fuel cell generation systems, considering thermal supply as well as electric power supply. In other words, the optimal operation of those sources can be determined easily by the principle of equal incremental fuel cost and the thermal merit of those sources can be also evaluated quantitatively through Kuhn-Tucker's optimal conditions. In additions, an priority method using the comparison of total cost at the peak load time interval is presented in order ot select the optimal locations of those sources. The validity of the proposed algorithms is demonstrated using a model system.

  • PDF

Evaluation of Pollution Level Attributed to Nonpoint Sources in Nakdonggang Basin, Korea (낙동강수계 권역별 비점오염원 오염도 평가)

  • Lee, Jaewoon;Kwon, Heongak;Choi, Hanyoung
    • Journal of Environmental Impact Assessment
    • /
    • v.23 no.5
    • /
    • pp.393-405
    • /
    • 2014
  • In this study, the nonpoint sources were evaluated by calculating the Nadonggang basin regional water quality and nonpoint source pollution load discharged. And were selected the banks of first administration based on the results and the direction of the next administration. As a results of estimating the water quality about BOD concentration in the mid influence area in the Nakdonggang basin, it was founded that 10 sites for 'Ia' water quality level, 6 sites for 'lb' water quality level, 5 sites for 'II' water quality level, 1 sites for 'I' water quality level. The estimation of COD concentration in the mid influence area, It showed that 9 sites for 'Ib' water quality level, 6 sites for 'II' water quality level, 6 sites for 'III' water quality level, 1 site for 'IV' water quality level. The assessment of water quality made Mid influence area of Gumhogang, Nakdong Goryung, Nakdong Milyang and Namgang selected as the mid influence area of high pollution. And delivery loads of nonpoint sources were calculated for mid influence area in Nakdonggang basin(max delivery load : 17,706.7 kg/day for Gumhogang influence area). As the result of calculating NPS(nonpoint sources) delivery load and water quality at influence area in Nakdonggang basin, Gumhogang influence area was selected as an area for management priority among nonpoint sources.

Research Priorities to Support Mandatory Implementation of a Total Pollutant Load Management System (TPLMS) in the Han River Basin (한강수계 의무적 수질오염총량관리제시행지원을 위한 조사·연구의 우선순위 설정)

  • Lee, Chang-Hee;Lee, Bum-Yeon;Lee, Su-Woong
    • Journal of Environmental Policy
    • /
    • v.8 no.4
    • /
    • pp.25-36
    • /
    • 2009
  • The Total Pollutant Load Management System(TPLMS) in the Han River basin is being changed from a voluntary to a mandatory system. Accordingly, this study suggests directions and priorities for research that can support implementation of TPLMS through an objective approach that deploys gap analysis and analytic hierarchy processes (AHP). Gap analysis indicated that TPLMS in Korea is still focused on compliance with regulations, and that implementation of TPLMS is still in its early stage. Improvements are thus needed in flexibility and effectiveness, including introduction of emissions rights trading, and upgrading to a renewable emissions permit system. The AHP study indicated that R&D will need to proceed in parallel in multiple areas to improve systems and resolve scientific uncertainties. Balanced R&D will be needed in both the institutional and technical groups. Subgroup analysis indicated that developing a reasonable process to establish water quality management targets is of the highest priority in the institutional group. In the technical group, higher priority will need to be given to improving model reliability and developing innovative pollution load reduction technologies.

  • PDF

The Application of SERVQUAL Distribution In Measuring Customer Satisfaction of Retails Company

  • Haming, Murdifin;Murdifin, Imaduddin;Syaiful, A. Zulfikar;Putra, Aditya Halim Perdana Kusuma
    • Journal of Distribution Science
    • /
    • v.17 no.2
    • /
    • pp.25-34
    • /
    • 2019
  • Purpose - This research strives to analyze and investigate customers' perception of the dimensions of service quality at retails in Makassar Municipality of Indonesia Country. This research tries to present its results empirically, which might be helpful to prepare a strategy to improve the service quality at retail companies. Research design, data, and methodology - The research uses Parasuraman's in 1985 unmodified SERVQUAL approach. This research is conducted using a questionnaire by purposive random sampling with 150 housewives customers who are met while they are shopping. The object of the study included several retail companies such as Alfa Mart, Alfa Midi, and Indomart operating in Makassar, Indonesia, which has been serving in 2017. Analysis was conducted by quantitative descriptive analysis, measurement of variable dimensions on the questionnaire using a Likert scale, and using cartecius graph and quadrant graphs to determine the gap size of each variable. Result - This research finds that the tangible and empathy dimensions such as product layout and lighting condition should be prioritized, and the empathy dimension whose gap value is too prominent such us peak load time condition and problem-solving adjustment. Conclusion - The second priority is responsiveness dimensions, and the last priority is reliability and assurance dimensions.

A Study on the Priority Ranking Algorithm for Bridge Management at Network Level (Network Level을 고려한 교량의 우선순위 산정 알고리즘에 관한 연구)

  • Kim Kwang-Soo;Kim Hyeong-Yeol;Park Sun-Kyu
    • Journal of the Korea Concrete Institute
    • /
    • v.17 no.3 s.87
    • /
    • pp.323-328
    • /
    • 2005
  • Bridge structures are properly designed in accordance with the design specifications with required safety margin. However, due to the heavy vehicle traffic and environmental attacks, bridge often requires repairs and the deteriorated one should be replaced or rehabilitated. In this paper, a prior ranking algorithm is proposed to assist a decision making process in bridge management at network level. Based on the literature survey for the existing studuies, two important factors which affect the decision making procedure for bridge management at network level are identified. These factors are implemented into the algorithm as a load carrying capacity function and traffic function, respectively.

A Relative Importance Evaluation for the Perception of Managers on the Comprehensive Rural Village Development Project using Analytic Hierarchy Process (계층분석과정(AHP)을 활용한 권역단위 종합정비사업 사무장 의식의 상대적 중요도 평가)

  • Jang, Dong-Heon
    • Journal of Korean Society of Rural Planning
    • /
    • v.21 no.1
    • /
    • pp.41-50
    • /
    • 2015
  • In this study, the relative importance for the perception of managers on the comprehensive rural village development projects was evaluated using the AHP method. The fields for evaluation were 4 fields including human relationships, working conditions, work compensation and work burnout. Also, the relative importance for the perception of managers and priority order were analyzed through 15 evaluation items. The analysis result shows that the human relationships among 4 fields were regarded as the most important field, followed by work compensation, working conditions and work burnout. Also, the relationship with the chairperson for the human relationships, continuity of employment for the working conditions, salary for work compensation, and mental stress for work burnout were considered respectively as the most important item. Also, salary among all evaluation items was considered as the most important item for the relative importance, followed by continuity of employment, relationship with village residents and mental stress. However, work load, consulting firms, impersonal treatment and the relations between the administration showed relatively low importance and priority order. It is considered that this analysis result will be used as important preliminary data for establishing the role of manager in the comprehensive rural village development project.

Synch. RA-based Uplink Packet Transmission in OFDMA Systems (OFDMA 시스템에서 동기 RA 방식 기반의 상향링크 패킷 전송)

  • Oh, Sang-Kyu;Moon, Jin-Soo;Shin, Seok-Joo
    • Journal of Internet Computing and Services
    • /
    • v.9 no.2
    • /
    • pp.25-33
    • /
    • 2008
  • In this paper we propose uplink packet transmission scheme based on Synchronized RA. The scheme can afford to support diverse QoS required from diverse multimeda traffics. In order to minimze the collision probability occurred in contention based channel access, we assign a reservation access channel additionally to the traffic channels. Access probability function for controlling collisions occurred in the reservation access channel is applied. Through assigning different access probability to each traffic user with respect to priority issued by his required QoS, the proposed scheme guarantees minimum throughput required by higher priority users in the whole range of system load.

  • PDF