• Title/Summary/Keyword: Demand and Supply

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New Prediction of the Number of Charging Electric Vehicles Using Transformation Matrix and Monte-Carlo Method

  • Go, Hyo-Sang;Ryu, Joon-Hyoung;Kim, Jae-won;Kim, Gil-Dong;Kim, Chul-Hwan
    • Journal of Electrical Engineering and Technology
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    • v.12 no.1
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    • pp.451-458
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    • 2017
  • An Electric Vehicle (EV) is operated with the electric energy of a battery in place of conventional fossil fuels. Thus, a suitable charging infrastructure must be provided to expand the use of electric vehicles. Because the battery of an EV must be charged to operate the EV, expanding the number of EVs will have a significant influence on the power supply and demand. Therefore, to maintain the balance of power supply and demand, it is important to be able to predict the numbers of charging EVs and monitor the events that occur in the distribution system. In this paper, we predict the hourly charging rate of electric vehicles using transformation matrix, which can describe all behaviors such as resting, charging, and driving of the EVs. Simulation with transformation matrix in a specific region provides statistical results using the Monte-Carlo Method.

지방정부 노인복지서비스의 수요·공급간 격차분석

  • Kim, Su-Yeong;Mun, Gyeong-Ju;Ju, Su-Hyeon;Kim, Do-Yeop
    • Journal of Local Government Studies
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    • v.26 no.2
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    • pp.87-112
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    • 2014
  • The entry of aging society and the coming of (super) aged society need overall the elderly welfare policy and budget for quantitative expansion and qualitative increase to the elderly welfare services. However, financial limit to the elderly welfare and increase to elderly welfare services in local government rely on central government or private sector. This study is discussed the gap between demands and supplies of the elderly welfare services in Busan Metropolitan City and policy implications suggested by these results. The major findings of the study are summarized as follows. First, the rate of the poor elderly under minimum living standard and the elderly housing facilities in demand of the elderly welfare services is reduced, but other measuring indicators are generally increased. Second, a per 10,000 elderly welfare service officials and a per 10,000 elderly medical welfare facilities in supply of the elderly welfare services are generally increased, but other measuring indicators are reduced. The policy implications of the study is to reduce the poor elderly under minimum living standard, to expend the elderly welfare budget, and adequately to supply a variety of the elderly welfare facilities for reduce demand of the elderly welfare services.

Issues in S&T Human Resources Development in Korea

  • 고상원
    • Journal of Technology Innovation
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    • v.4 no.1
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    • pp.185-207
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    • 1996
  • It is frequently pointed out that the Korean economy, with its scarce natural resources, would never have been able to achieve current levels of economic development without the massive provision of well-educated, hardworking human resources. Throughout the industrialization process ,full-fledged deployment and mobilization of qualified human resources have been the foundation to industrial policy and S&T policy. This paper describes the development of S&T human resources in Korea using various statistics including educational enrollment rates, unemployment rates, the allocation of researchers and R&D expenditures among sectors of performance, educational composition of employment within and across industries, technical human resource shortage rates, relative wage levels of SMEs, and composition of labor force by age-group and gender. While analyzing S&T human resources development, this paper discusses issues such as the mismatched demand and supply of skill and knowledge levels of the highly educated, the unbalanced distribution of S&T human resources between sectors, and the low utilization of the female and aged labor force. This paper suggests that the policy maker applies a hybrid of quantitative and qualitative policies to reduce the mismatches of supply and demand of skill and knowledge levels for each labor market categorized according to supply side.

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An Analysis of Demand Elasticity to Facilitate the Use of Public Transportation in the Administrative City (행정중심복합도시 대중교통 이용활성화를 위한 수요탄력성 분석)

  • Kim, Tae-Gyun;Park, Ji-Eun;Lee, Yun-Sang
    • Land and Housing Review
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    • v.9 no.3
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    • pp.9-18
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    • 2018
  • Administrative city has been developed step by step aiming to being a public transport-oriented new city. In spite of its primary goal, administrative city is dominated by car-oriented tansportaion system because the supply of public transportation has not been adequately and timely performed. In this study, we investigate the current situation related to (public) transportation use in administrative city. Also, we examine the issues of traffic system through a survey on residents' consciousness about public transportation use. Additionally, the analysis of demand elasticity according to the change of the conditions of using public transportation and passenger car is conducted for passenger car users. As a result, it is analyzed that as the neighborhood is more stabilized after the completion of development the resistance to the abandonment of passenger car is higher when the tide demand control method is introduced. Therefore, it is concluded that pre-emptive public transportation supply and the management of car demand management are necessary for the activation of public transportation in Administrative city.

Public Policy and The Imbalance of The Systems: A System Dynamics Approach for The Shock of Lowered Retirement Age of Teachers on Education System

  • Yi, Mi-Sook;Choi, Nam-Hee;Kim, Doa-Hoon
    • Korean System Dynamics Review
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    • v.5 no.2
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    • pp.149-174
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    • 2004
  • Since the economic crisis in 1997, the Korean government has implemented a number of reforms in order to eliminate inefficiencies in both private and public sectors. One of the reforms made in the public sector was to lower the retirement age of teachers from the original age of 65 to that age 62. The ultimate aim of this compulsory policy was to improve the quality level of education by hiring many young teachers instead of senior teachers. It was made based on the calculation that by lowering the retirement age by three years, the government can hire three young teachers with the saved wages. However, this policy has brought an unexpected result; the imbalance between the supply and demand for teachers has become a much more serious problem in Korea's elementary education system The purpose of this study is largely twofold; First of all, it aims to identify the scope of imbalances occurred in the supply-demand system of elementary school teachers in a region of the nation, and also to find out why such imbalance occurred. Secondly, the purpose of this study is to experiment with feasible policy alternatives and their effects on the system and to suggest some resolutions on the imbalance.

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Scenario Analysis of Low-Carbon Generation Mix Considering Social Costs (사회적 비용을 고려한 저탄소 전원구성의 시나리오 분석)

  • Park, Jong-Bae;Cho, Young-Tak;Roh, Jae Hyung
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.67 no.2
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    • pp.173-178
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    • 2018
  • This study organizes scenarios on the power supply and demand plans considering the uncertainties and the portion of distributed energy resources. In analysing the scenarios, it estimates total electricity supply cost in the social aspect, natural gas demand and air pollutants emission including carbon dioxide. Also the analysis is performed to estimate the marginal cost of carbon dioxide reduction for the fuel switching from coal to liquified natural gas. In result, the social cost could be decreased by replacing some portion of renewable energy by LNG-based combined heat and power and delaying the construction of large base-load generators such as coal and nuclear plants. The marginal carbon dioxide reduction cost by fuel switching is in plausible range for fuel switching to be an option for carbon dioxide emission reduction when the social cost is considered.

A Study on the Cooling Load Generation for Efficient Energy Management (냉방부하 수요 창출을 통한 효율적 에너지 관리방안 연구)

  • Woo, Nam-Sub;Kim, Yong-Ki;Lee, Tae-Won
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.1007-1012
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    • 2008
  • Demand for the highly efficient and high performance urban energy supply system having been continuously increased according to the rise of quality of life and continuously increased energy cost all over the world. The district heating and cooling system is very effective way for energy saving, cost reduction, and demand side management of energy. There are several district cooling supply technologies such as chilled water direct transportation, installation of absorption type chiller in the user side, and desiccant cooling. This study investigates the advantage and technical problems of each district cooling technology. Also, it is necessary political and financial support system for the extension of district cooling system.

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Study on the Oversea Technology Development of Electric Power Storage System and It's Domestic Application (전력저장시스템 기술개발 국외동향 분석 및 국내 활용방안 연구)

  • Choi, Kyung-Shik;Yang, Seung-Kwon
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2008.10a
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    • pp.57-60
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    • 2008
  • As the technology of a large scale battery have advanced, it's application to the electric power network have been active in foreign country. By providing the electric power energy stored in the electric power storage system when needed, there are many advantages that it is able to reduce the gap between the electric power demand and supply for day and night to increase capacity factor, to upgrade the electric power quality degraded from the unbalance between power demand and supply and to compensate the fluctuation of wind power plant and photovoltaic power generation. In this study, the current application of electric power storage system using battery is introduced in detail, and I have thought out it's application fields based on the foreign examples. These are demand side response, upgrade of the power quality, stabilization of fluctuation of renewable energy and distributed generation for filling elapse.

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Portfolio Analysis on the New Power Generation Sources of the Sixth Basic Plan for Long Term Electricity Demand and Supply (포트폴리오 이론을 활용한 제6차 전력수급기본계획의 신규전원구성 비교 연구)

  • Kim, Juhan;Kim, Jinsoo
    • Environmental and Resource Economics Review
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    • v.23 no.4
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    • pp.583-615
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    • 2014
  • Including the rolling black out in 2011, Korea has suffered from rapid increase of electricity consumption and demand forecasting failure for last five years. In addition, because of the Fukushima disaster, high fuel prices, and introduction of new generation sources such as renewables, the uncertainty on a power supply strategy increases. Consequently, a stable power supply becomes the new agenda and a revisino of strategy for new power generation sources is needed. In the light of this, we appraises the sixth basic plan for long term electricity demand and supply considering the changes of foreign and domestic conditions. We also simulate a strategy for the new power generation sources using a portfolio analysis method. As results, a diversity of power generation sources will increase and the share of renewable power generation will be surged on the assumptions of a cost reduction of renewable power sources and an increase of fuel costs. Particularly, on the range of a risk level(standard deviation) from 0.06 and 0.09, the efficient frontier has the most various power sources. Besides, the existing power plan is not efficient so that an improvement is needed. Lastly, the development of an electricity storage system and energy management system is necessary to make a stable and efficient power supply condition.

Recognition and Demand Analysis of Agro-healing Services by Supply Types (치유농업 형태별 수요자 인식 및 수요분석)

  • Bae, Seung-Jong;Kim, Dae-Sik;Kim, Soo-Jin;Kim, Seong-Pil;Lee, Wang-Lok;Ryu, Jin-Seok;Kim, Jeong-Eun;Park, Sin-Ae
    • Journal of Korean Society of Rural Planning
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    • v.25 no.4
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    • pp.1-11
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    • 2019
  • This study conducted a survey on the recognition and demand such as recognition level, policy necessity, service demand and policy demand by supply types in order to provide the basic data for successful settlement of agro-healing services. According to the survey on awareness, 45.2% of respondents were aware of the healing farming, and 31.3% of respondents had experience in participating in the agro-healing services. 63.6% of respondents replied that they were experiencing reasons for participating in agro-healing services. Respondents who had no knowledge of agro-healing services responded that 76.7% of respondents said they would not participate. More than two-thirds of respondents in all types indicated that they needed agro-healing services. As a result of evaluating the maximum willingness to pay, there was a willingness to pay for farm work healing about 15,800 won, horticulture healing about 14,800 won, forest healing about 13,400 won, and animal assisted healing about 17,000 won. Improving accessibility and strengthening awareness were high priorities for inconveniences and improvements. 70.1% of the respondents said that policies for agro-healing services are needed. Development of agro-healing programs and contents was the first priority for support policy. The result of this study is expected to provide reference data that can be suggested for agro-healing policy establishment.