• 한국태양에너지학회 논문집
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• 제30권2호
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• pp.81-86
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• 2010

Since the solar energy resource is the main input for sizing any solar photovoltaic system and solar thermal power system, it is essential to utilize the solar radiation data as a application and development of solar energy system increase. It will be necessary to understand and evaluate the insolation data. The Korea Institute of Energy Research(KIER) has begun collecting horizontal global insolation data since May, 1982 and direct normal insolation data since December 1992 at 16 different locations in Korea. Because of a poor reliability of existing data, KIER's new data will be extensively used by solar energy system users as well as by research institutes. From the results, the yearly averaged horizontal global insolation was turned out 3.60kWh/$m^2$/day and a significant difference of horizontal global insolation is observed between 1982~1990 and 1991~1999, 2000~2008 through 16 different cities in Korea.

• 농촌계획
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• 제21권1호
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• pp.1-8
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• 2015

Population growth and increasing consumption of resources in the process of the industrial development has caused environmental pollution, climate change, and resource exhaustion. Therefore 'sustainable development' has become the important issue for the future. The sustainable development aims at effective resource use, less environmental impacts, and higher social security. Generally the rural area including agricultural fields and forest has various and plentiful natural resources which could make future development sustainable. To develop potential rural resources, the values for energy, environment and economy should be assessed considering the life-cycle of resources. The purposes of this study are to suggest the E3 (Energy, Environment, and Economy) assessment model for rural biomass considering life-cycle of resource and to apply the model to rice, the major agricultural product. As the results of this study, it turned out through E3 assessment that economic gain of rice cultivation is 578,374 won/10a, carbon absorption is $1,530kgCO_2/10a$, carbon emission is $926.65kgCO_2/10a$, and bio-energy potential of by-product is 394,028 kcal/10a. When E3 assessment was applied to by province, the results varied by regions because of the amount of input during cultivation. These results would be useful to realize the rural biomass and design regional resources plan in integrated E3 perspective.

• 한국환경과학회지
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• 제18권8호
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• pp.877-883
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• 2009

This study has analyzed the scale, location, resource potential and feasibility of offshore wind farm scientifically and systematically based on the national wind map and GIS. For long-term wind power development, this study pursues siting strategy building, selection of target area and deciding development priority as well as the presenting a basis for assessment that are necessary for policy decision making by making theme layers under GIS environment. According to the analysis after organizing technological development by stages, even if only the most suitable sites are developed among the area of offshore wind farm candidates that can be developed under the current technological standard, it has been evaluated as being able to develop about 3 times of the wind power dissemination target until 2012. It is expected that about 5% of territorial water area can be developed in a short-term future while the southern offshore area possessing relatively favorable wind resource than the western offshore has been identified as the most feasible site. While about 23% of territorial water area has been classified as potential area for offshore wind farm development in a long-term future, even Jeju Island and offshore of Ulsan possessing excellent wind resource have been analyzed as feasible sites. The feasibility assessment of offshore wind lam development established by this study is expected to assist national strategy building for accomplishing the wind power dissemination target.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권3호
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• pp.921-940
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• 2015

In this paper, we investigate the multi-resource allocation problem, a unique feature of which is that the multiple resources can compensate each other while achieving the desired system performance. In particular, power and time allocations are jointly optimized with the target of energy efficiency under the resource-limited constraints. Different from previous studies on the power-time tradeoff, we consider a multi-server case where the concurrent serving users are quantitatively restricted. Therefore user selection is investigated accompanying the resource allocation, making the power-time tradeoff occur not only between the users in the same server but also in different servers. The complex multivariate optimization problem can be modeled as a variant of 2-Dimension Bin Packing Problem (V2D-BPP), which is a joint non-linear and integer programming problem. Though we use state decomposition model to transform it into a convex optimization problem, the variables are still coupled. Therefore, we propose an Iterative Dual Optimization (IDO) algorithm to obtain its optimal solution. Simulations show that the joint multi-resource allocation algorithm outperforms two existing non-joint algorithms from the perspective of energy efficiency.

• 한국기술혁신학회:학술대회논문집
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• 한국기술혁신학회 2010년도 춘계 학술대회 논문집
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• pp.3-14
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• 2010

Through time-series plots, we can see relatively stable trend of energy factor share and the decreasing trend of relative energy prices (to wages) in Korea. We can compromise these empirical facts with the following explanation: if elasticity of substitution between capital and energy is smaller than one(<1) in Korea, a change(decrease) in energy price can prevent income share of resources from rising in the process of economic growth. This is consistent with theoretical and empirical results that substitution between energy and capital is so difficult. From simple empirical analysis and limited information, we can carefully infer that, in the past in Korea, resource-specific innovation was performed widely. Finally, If we are to reduce the magnitude of "growth drag", we should decrease energy factor share. This can be accomplished by energy-augmenting technical progress in the case of elasticity of substitution less than 1 as in Korea.

• 한국태양에너지학회 논문집
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• 제36권1호
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• pp.27-37
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• 2016

A simple but practical Ensemble Prediction System(EPS) for wind power forecasting was developed and evaluated using the measurement of the offshore meteorological tower, HeMOSU-1(Herald of Meteorological and Oceanographic Special Unite-1) installed at the Southwest Offshore in South Korea. The EPS developed by the Korea Institute of Energy Research is based on a simple ensemble mean of two Numerical Weather Prediction(NWP) models, WRF-NMM and WRF-ARW. In addition, the Kalman Filter is applied for real-time quality improvement of wind ensembles. All forecasts with EPS were analyzed in comparison with the HeMOSU-1 measurements at 97 m above sea level during Typhoon Bolaven episode in August 2012. The results indicate that EPS was in the best agreement with the in-situ measurement regarding (peak) wind speed and cut-out speed incidence. The RMSE of wind speed was 1.44 m/s while the incidence time lag of cut-out wind speed was 0 hour, which means that the EPS properly predicted a development and its movement. The duration of cut-out wind speed period by the EPS was also acceptable. This study is anticipated to provide a useful quantitative guide and information for a large-scale offshore wind farm operation in the decision making of wind turbine control especially during a typhoon episode.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 A
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• pp.357-359
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• 2004

Fuse is the initial equipment of Protective Relay The installation standard of Fuse has been used for long time in Power Facilities. However according to the innovative development of Electric & Electronic element(=semiconductor) Technology, Protective Relay and other Power Equipments are being changed into Digitalization and Multi-Functional Convergence. In contrast with it, the installation standard of Fuse is just the same. There is a need to give careful consideration to it. This study will bear a Part of producing a safe and efficient Power by examining the current installation of primal 8f secondary 1'use in multi-functional PT of Power plant, giving a problem careful consideration and suggesting suitable countermeasures.

• 한국환경복원기술학회지
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• 제11권4호
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• pp.12-23
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• 2008

This study has a purpose of setting applicable ecological environment plan items when establishing city development plan. To achieve this purpose, multiple methods of data gathering, documentary surveys, and questionaries research were used in this study. The main findings of this study can be summarized as follows; 1. The appliance of ecological environment plan is appropriate to apply before the establishment of development plan. 2. The items applicable to ecological environment plan establishment step by step is the following. First, it is necessary to prepare the environment improvement plan and ecology restoration on the stage of assigning the area. Second, on the stage of planning development plan, it is required to set the restoration plan of ecological resources and step by step ecological environment plan. Third, on the stage of plan implementation, it is required to set the maintenance guide on ecological environment. 3. The planning items of ecological environment plan are "geographical features and soil", "water resource", "wind resource", "green resource", "circulation of resource", "usage of nature energy" and "habitats", etc. 4. To apply ecological environment plan to the planning of development, it is necessary to specify the clear concepts and specific plan. 5. This study is limited to select generalized planning items and later on, it is necessary to develop detailed planning contents.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1728-1730
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• 2005

Many domestic organizations are pushing ahead with small hydropower business to develop a renewable energy. In addition each organization gradually spreads small hydropower business with searching the best site for it. And KOWACO(Korea Waters Resources Corporation) answers a purpose of the government policy to spread the wide use of a renewable energy. This study explains the researching programs for the best development sites for small hydropower generation with using water pipes managed and controled by KOWACO.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권3호
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• pp.794-815
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• 2023

The rapid development of mobile communication not only has made the industry gradually diversified, but also has enhanced the service quality requirements of users. In this regard, it is imperative to consider jointly network slicing and mobile edge computing. The former mainly ensures the requirements of varied vertical services preferably, and the latter solves the conflict between the user's own energy and harsh latency. At present, the integration of the two faces many challenges and need to carry out at different levels. The main target of the paper is to minimize the energy consumption of the system, and introduce a multi-slice joint task offloading and resource allocation scheme for massive multiple input multiple output enabled heterogeneous networks. The problem is formulated by collaborative optimizing offloading ratios, user association, transmission power and resource slicing, while being limited by the dissimilar latency and rate of multi-slice. To solve it, assign the optimal problem to two sub-problems of offloading decision and resource allocation, then solve them separately by exploiting the alternative optimization technique and Karush-Kuhn-Tucker conditions. Finally, a novel slices task offloading and resource allocation algorithm is proposed to get the offloading and resource allocation strategies. Numerous simulation results manifest that the proposed scheme has certain feasibility and effectiveness, and its performance is better than the other baseline scheme.