• Title/Summary/Keyword: demand control

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Water Quality Monitoring for Hazard Analysis in Aquaculture Farm of Rainbow Trout (송어양식장의 위해요소 관리를 위한 수질 모니터링)

  • Kim, Young-Mog;Lee, Myung-Suk;Chung, Yong-Hyun
    • Journal of Fisheries and Marine Sciences Education
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    • v.25 no.4
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    • pp.819-827
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    • 2013
  • Water quality has been considered to be one of sanitation standard operating procedures (SSOP) for hazard analysis critical control points (HACCP) application in aquaculture farms. This study was conducted to evaluate a hazard caused by water used in aquaculture farm of rainbow trout. The water quality was analyzed to investigate both physiochemical and bacteriological level in water samples collected from aquaculture farm of rainbow trout, Oncorhynchus mykiss. No significant difference were observed on water temperature and pH from season to season. However, the levels of dissolved oxygen were decreased as the outside temperature was increased, even if the levels were adequate for aquaculture. Also, other physiochemical analysis including biochemical oxygen demand (BOD), chemical oxygen demand (COD) and suspended solid (SS) revealed that the waters for aquaculture analyzed in this study was suitable for rainbow trout aquaculture. The bacterial analyses were also revealed that the waters for aquaculture were met to both coliform group (<18 MPN/100mL) and viable cell count (<100 CFU/mL). However, some of waste waters from aquaculture farms showed higher levels of BOD and COD than those of waste water standard (<2 ppm), suggesting that regular cleaning of fish tank and precipitation tank is needed.

DSM Resources Evaluation and Customer Behavior Analysis (DSM 자원평가 및 소비자 행태 분석)

  • Ahn, Nam-Seong;Park, Min-Hyuk;Rhu, Jae-Gook
    • Korean System Dynamics Review
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    • v.5 no.1
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    • pp.49-71
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    • 2004
  • Demand-side Management can be defined as'any utility activity aimed at modifying customers' use of energy to produce desired changes in the utility's load shape'. Customers benefit by being able to control energy costs and improve quality of life and become more productive. Utilities benefit from DSM's value as a resource that enhances asset utilization and reduces both fuel costs and environmental emissions. The scope of DSM includes load management through rate schedules and conservation by improving energy effciency and using electricity consumption effectively. This paper study the DSM resource evaluation and customer behavior analysis todesign the DSM Program plan in response to customer needs. We develop basic system dynamics model to analysis the customer behavior based on a survey research. The DSM Program participants in the Hi- efficiency Inverter, Electric motor and efficient lighting applicancies operating by Conservation program 2002 become the survey objects. DSM resource evaluation evaluate firstt the distribution potentialities of each machine and then forecast the degree of diffusion. We apply the system dynamic approach to simulate the dynamic DSM market situation at the domestic beginning. This model will give the energy Planner the opportunity to create different scenarios for DSM program planning. Also it will lead to increased understanding of the dynamic DSM market

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An Optimal Procedure for Sizing and Siting of DGs and Smart Meters in Active Distribution Networks Considering Loss Reduction

  • Sattarpour, T.;Nazarpour, D.;Golshannavaz, S.;Siano, P.
    • Journal of Electrical Engineering and Technology
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    • v.10 no.3
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    • pp.804-811
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    • 2015
  • The presence of responsive loads in the promising active distribution networks (ADNs) would definitely affect the power system problems such as distributed generations (DGs) studies. Hence, an optimal procedure is proposed herein which takes into account the simultaneous placement of DGs and smart meters (SMs) in ADNs. SMs are taken into consideration for the sake of successful implementing of demand response programs (DRPs) such as direct load control (DLC) with end-side consumers. Seeking to power loss minimization, the optimization procedure is tackled with genetic algorithm (GA) and tested thoroughly on 69-bus distribution test system. Different scenarios including variations in the number of DG units, adaptive power factor (APF) mode for DGs to support reactive power, and individual or simultaneous placing of DGs and SMs have been established and interrogated in depth. The obtained results certify the considerable effect of DRPs and APF mode in determining the optimal size and site of DGs to be connected in ADN resulting to the lowest value of power losses as well.

Improvement method of process management on new han-ok style public building project (신한옥형 공공건축물 실증구축사업의 작업진도 분석 및 공정개선 방안 - 신한옥형 공공건축물 실증구축 현장 3개를 중심으로 -)

  • Seo, Jung-Seung;Kim, Young-Hoon;Kwak, Dong-Yeob
    • KIEAE Journal
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    • v.17 no.3
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    • pp.133-140
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    • 2017
  • Purpose: The construction of New Han-ok style public buildings is a construction that can not be seen in traditional Han-ok, and it is a construction that combines traditional wooden structure, RC structure, and steel structure. Therefore, construction different from general construction is complicated and complex. It is necessary to accurately understand the construction method of each field rather than the general construction management method and study the method suitable for New Han-ok style public buildings. Also, since the New Han-ok style public building business is the first business to be introduced in Korea, new process management is needed rather than general process management. Method: The research method is as follows. Analyze process management through theoretical considerations and analyze the differences from general construction projects. Next, we want to identify the characteristics and problems of the process control method applied to real cases. Finally, the results of this analysis suggest ways to improve process management. Result: Therefore, it is necessary to establish a precise plan from the basic design to the construction of the public building construction management. In addition, careful planning should be made so that the supply and demand of materials and the supply and demand of personnel can be achieved smoothly.

The Improvement Proposal of Control System for Supply and Demand of Korean Optometrist (안경사 인력 수급 및 관리제도 개선방안)

  • Kim, Sang-Hyun;Lim, Yongmoo
    • Journal of Korean Ophthalmic Optics Society
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    • v.12 no.4
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    • pp.9-14
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    • 2007
  • We have studied the problems associated with increasing number of ophthalmic optics students every year. The main problems are surplus supply of the optometrist and poor working condition. Thus all parties concerned who aim to solve the numerical unbalance of optometrist must have the common policy in sight. And we have to make a long-term plan and permanent organization for medical technician to establish supply and demand of medical technician with exact policy. To solve this unbalance of optometrist numbers, we have to establish an exact job category, reform the specialized education course, estimate the practical technique of national licensing examination for Korean optometrist, and innovate the contents and methods of reeducation.

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Monitoring of Non-point Source Pollutants Generated by a Flower Farm

  • Choi, Byoungwoo;Kang, Meea
    • The Journal of Engineering Geology
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    • v.24 no.4
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    • pp.463-471
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    • 2014
  • This paper considers the effect of rainfall on non-point source (NPS) pollutant loads. The impact of runoff on the occurrence of NPS pollutants was found to be influenced by rainfall amount, rainfall intensity, and the number of antecedent dry days (ADD), both independently and in combination. The close correlation ($R^2$ = 0.9920) between rainfall and runoff amounts was demonstrated at the study site (a flower farm) over the period between January 2011 and December 2013. The relationships among pollutant levels, runoff, and rainfall was not satisfactory results except for the Biochemical Oxygen Demand ($BOD_5$). The correlation coefficients between $BOD_5$, and both runoff and rainfall, were greater than 0.92. However, the relationships of other pollutants, such as Suspended Solid (SS), Chemical Oxygen Demand ($COD_{Mn}$), Total Nitrogen (TN), and Total Phosphorus (TP), with runoff and rainfall had correlation coefficients of less than 0.70. The roles of rainfall was different from rainfall categories on the occurrence of runoff. Instantaneous rainfall intensity was a principle factor on the occurrence of runoff following light rainfall events (total ${\leq}30mm$). For rainfall of intermediate intensity (total precipitation 31-50 mm), the combined effect of both average rainfall intensity and ADD was found to influence runoff generation. We conclude that the control of NPS pollutants with the reflection of the climate change that makes the remarkable effect of amounts and forms on the rainfall and runoff.

Workers' Job Stress Status and Related Factors - Using Korean Occupational Stress Questionnaire Short Form - (근로자들의 직무스트레스 수준과 관련 요인 - 한국형 직무스트레스 측정도구 단축형을 이용하여 -)

  • Cho, Tong Ran
    • Korean Journal of Occupational Health Nursing
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    • v.15 no.1
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    • pp.58-71
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    • 2006
  • Purpose: This study was performed to identify workers' Job stress status and to analyse the influencing factors. Method: Data were collected from 456 workers with Korean Occupational Stress Questionnaire Short Form(KOSQ SF) and analysed using descriptive statistics, t-test, ANOVA. Results: Total job stress status of men was slightly lower than Korean workers' standard. In case of women, the score of total job stress was lower than Korean workers' standard. The most significant influencing factors to stressors were insufficient sleeping time and self cognitive bad health condition. Among seven domains of job stressors, job demand was affected by 8 characteristics. Conclusion: This study indicated that workers' job stress level were various by their characteristics except workplace size. The development of stress management programs by types of industry is required. On the base of the model program, planning of customized program for every company or employee is required. High job demand, insufficient job control, insufficient sleeping time, bad health condition are the key factors of workers' job stress in this study. The change of workers' health behavior with supportive environment is essential to stress management program. More researches for adding physical environment domain to KOSQ SF are expected.

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Development Plans of Egg Industry Using International Comparison (국제비교를 통한 계란산업의 발전방안)

  • Kim, Yoon-Doo;Kim, Dong-Jin;Chae, Sue-Ho
    • Korean Journal of Poultry Science
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    • v.47 no.1
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    • pp.39-48
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    • 2020
  • The present study intended to analyze and detect any possible shortcomings in the current egg distribution system in Korea through a questionnaire. The institutional system and cases of operation thereof in advanced countries such as the USA, Japan, and Germany for the development of the egg distribution industry in Korea. The results revealed the following issues: absent pricing system, ineffective egg distribution, and difficulty in balancing supply and demand. Suggestions for addressing these issues and the subsequent improvement were based on cases found in the instated systems of advanced countries, and were given as follows: (i) The existing GP Center needs to be separated from the farms of laying hens, and the current institutional system and its operations need to be improved and should be approved by the government. Parallel to the institutional improvement, establishing a distribution system centered on the GP Center would be desirable. (ii) Egg pricing regulations are needed as a standard to determine the price of eggs. (iii) The reinforcing control standards and securing means for egg preservation are pertinent to each stage of egg distribution and should take into account environmental factors such as egg preservation temperature to guarantee high hygiene standards and egg safety.

Energy Saving Potentials of Ventilation Controls Based on Real-time Vehicle Detection in Underground Parking Facilities

  • Cho, Hong-Jae;Park, Joon-Young;Jeong, Jae-Weon
    • International Journal of High-Rise Buildings
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    • v.2 no.4
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    • pp.331-340
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    • 2013
  • The main topic of this paper is to show a possibility of indoor air quality enhancement and the fan energy savings in underground parking facilities by applying the demand-controlled ventilation (DCV) strategy based on the real-time variation of the traffic load. The established ventilation rate is estimated by considering the passing distance, CO emission rate, idling time of a vehicle, and the floor area of the parking facility. However, they are hard to be integrated into the real-time DCV control. As a solution to this problem, the minimum ventilation rate per a single vehicle is derived in this research based on the actual ventilation data acquired from several existing underground parking facilities. And then its applicability to the DCV based on the real-time variation of the traffic load is verified by simulating the real-time carbon monoxide concentration variation. The energy saving potentials of the proposed DCV strategy is also checked by comparing it with those for the current underground parking facility ventilation systems found in the open literature.

Development of Efficient Operational Mode for Wind-Diesel Hybrid System

  • Asghar, Furqan;Kim, Se-Yoon;Kim, Sung Ho
    • Journal of the Korean Institute of Intelligent Systems
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    • v.24 no.5
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    • pp.554-561
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    • 2014
  • Hybrid wind Diesel stand-alone power systems are considered economically viable and effective to create balance between production and load demand in remote areas where the wind speed is considerable for electric generation, and also, electric energy is not easily available from the grid. In Wind diesel hybrid system, the wind energy system is the main constitute and diesel system forms the back up. This type of hybrid power system saves fuel cost, improves power capacity to meet the increasing demand and maintains the continuity of supply in the system. Problem we face in this system is that even after producing enough power through wind turbine system, considerable portion of this power needs to be dumped due to short term oversupply of power and to maintain the frequency within close tolerances. As a result remaining portion of total energy supplied comes from the diesel generator to overcome the temporal energy shortage. This scenario decreases the overall efficiency of hybrid power system. In this study, efficient Simulink modeling for wind-diesel hybrid system is proposed and some simulations study is carried out to verify the feasibility of the proposed scheme.