• Title/Summary/Keyword: Energy problems

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Design of T-S(Takagi-Sugeno) Fuzzy Control Systems Under the Bound on the Output Energy

  • Kim, Kwang-Tae;Joh, Joog-Seon;Kwon, Woo-Hyen
    • Transactions on Control, Automation and Systems Engineering
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    • v.1 no.1
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    • pp.44-49
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    • 1999
  • This paper presents a new T-S(Tae-Sugeno) fuzzy controller design method satisfying the output energy bound. Maximum output energy via a quadratic Lyapunov function to obtain the bound on output energy is derived. LMI(Linear Matrix Inequality) problems which satisfy an output energy bound for both of the continuous-time and discrete-time T-S fuzzy control system are also derived. Solving these LMIs simultaneously, we find a common symmetric positive definite matrix P which guarantees the global asymptotic stability of the system and stable feedback gains K's satisfying the output energy bound. A simple example demonstrates validity of the proposed design method.

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Continuous Commissioning Process and Application (Continuous Commissioning의 절차와 적용)

  • Cho, Young-Hum
    • Journal of the Korean Solar Energy Society
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    • v.30 no.5
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    • pp.77-84
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    • 2010
  • This paper presents the continuous commissioning process, information on the case study facility, improved system operation, and building energy consumption measures before and after continuous commissioning implementation. Continuous commissioning is an ongoing process to resolve operating problems, improve comfort, optimize energy use and identify retrofits for existing commercial and institutional buildings and central plant facilities. Continuous commissioning process consists of two phases. The first phase is the project development phase and the second phase implements and verifies project performance. Results of a case study show that continuous commissioning implementation can reduce energy costs. The energy reports show the electricity savings of 22% and gas savings of 47% on an average.

A Study on the Planning of Rural Housing of Energy Saving Type Environmental Friendly (에너지 절약형 친환경 농어촌주택 디자인 방향에 관한 연구)

  • Son, Kwang-Ho;Jeong, Do-hwa;Shin, Jung-Sook;Kim, Kang-Seob
    • Journal of the Korean Institute of Rural Architecture
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    • v.12 no.4
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    • pp.13-20
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    • 2010
  • This study takes notes on energy problems and sustainability of rural housing. The purpose of this study was to analyze the actual conditions of rural and applying energy saving of rural housing. For this, we tried to review literatures and conduct a field survey. The results of this study were as follows, first, rural housing of energy saving type environmental friendly applied planning factors with gradual carbon decrease by considering economic efficiency, current application and technical level. Second, the principal concepts of this housing are economic, locality and energy efficiency, it is applicable three kinds of the concepts of environmentally friendly housing. Third, this housing in planning must decrease energy consumption and increase air conditioning efficiency by means of air tightness and improvement insulation capacity.

A Research on the Energy Data Analysis using Machine Learning (머신러닝 기법을 활용한 에너지 데이터 분석에 관한 연구)

  • Kim, Dongjoo;Kwon, Seongchul;Moon, Jonghui;Sim, Gido;Bae, Moonsung
    • KEPCO Journal on Electric Power and Energy
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    • v.7 no.2
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    • pp.301-307
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    • 2021
  • After the spread of the data collection devices such as smart meters, energy data is increasingly collected in a variety of ways, and its importance continues to grow. However, due to technical or practical limitations, errors such as missing or outliers in the data occur during data collection process. Especially in the case of customer-related data, billing problems may occur, so energy companies are conducting various research to process such data. In addition, efforts are being made to create added value from data, which makes it difficult to provide such services unless reliability of data is guaranteed. In order to solve these challenges, this research analyzes prior research related to bad data processing specifically in the energy field, and propose new missing value processing methods to improve the reliability and field utilization of energy data.

Exploring the Transformative Regional Innovation Policy and Applying Local Energy Transition: The Case Studies of Gussing, Austria and Esbjerg, Denmark (전환적 지역혁신론의 탐색과 지역에너지 전환의 적용: 오스트리아 귀씽과 덴마크 에스비아르 사례를 중심으로)

  • HAN, Jae kak;LEE, Jung-pil;HA, Vara;SONG, Wichin
    • Journal of Science and Technology Studies
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    • v.19 no.3
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    • pp.291-333
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    • 2019
  • The regional innovation policies so far have been separated from the social problems facing the local communities. The regional innovation policies, regarding the region as the location of the business, have focused on the invigoration of business innovation activities. However, as the recent emergence of the new paradigm of innovation policy aiming the sustainability, 'transformative innovation policy,' has led to a search for regional innovation policies that begin with solving the local social problems. This research paper deals with regional innovation theory that starts from searching for solutions and system transformation for social problems such as climate crisis and energy problems. The objective is to present a new framework called 'transformative regional innovation policy' and to improve its content through case studies by combining the results of the transformative innovation policy and the regional innovation policy studies. In particular, the contribution of this paper is to analyze and discuss the concept of the transition platform, which aims to solve the local social problems, through the case studies of Gussing, Austria and Esbjerg, Denmark. Lastly, it discusses the derived implications of the cases applied in Korean society.

System Design for Activation of Renewable Energy and Cooperative Renewable Energy Plan Between South and North Korea -Based on the Survey of Renewable Energy Experts- (신.재생에너지 활성화를 위한 제도의 설계와 남북한 신.재생에너지 협력 추진방안 - 전문가 설문에 나타난 신.재생에너지 현황 -)

  • Lim, So-Young;Heo, Eun-Nyeong
    • New & Renewable Energy
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    • v.1 no.3 s.3
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    • pp.24-34
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    • 2005
  • Ministry of Commerce, Industry [MOCIE] has taken it into consideration to introduce a Renewable Portfolio Standard (RPS) that is a purchase obligation program as an alternative plan to the FIT. We conducted a survey of renewable energy companies and experts to ask their opinions about renewable energy policy, the introduction of the RPS, and the scheme for aid of North Korea with renewable energy. Korean renewable energy companies show an impartial opinion about a FIT and a RPS system overall, although they tend to have distinctive opinions by technology each other. With respect to eligible resources for a RPS, the industries want to extend the scope of it as broad as possible. In addition, experts prefer the multi-tiered and energy production based RPS to the sing1e-tiered and installed capacity based RPS. We also conducted a surrey to find the best renewable energy sources. Wind, Geothermal, Solar-thermal, and Photovoltaic were selected to have the best potential capacities to support North Korea by renewable energy experts. However, these energy resources also have several problems to overcome in the aid of North Korea, and thus, the plans for solving them and for giving efficient support to North Korea in the area of Renewable Energy are discussed.

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Comparing Performances of Factors for Reducing Energy at Deteriorated Elementary School Buildings (노후 초등학교 건물에너지 절감을 위한 요소기술의 성능 비교)

  • Lhee, Sang-Choon;Choi, Young-Joon;Kim, Hyun-Ki;Choi, Yool
    • KIEAE Journal
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    • v.12 no.2
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    • pp.111-116
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    • 2012
  • Faced with the international issue of environmental problems from global warming and energy consumption, the Korean Government has made many efforts on reducing energy and $CO_2$ emission under the motto of "Low-Carbon Green Growth". In order to reduce energy in the building sector, severe design standards and regulations on saving energy in new buildings have been established. Now, it is necessary to focus on deteriorated buildings where applications of energy saving designs and techniques have been insufficient, for maximizing energy saving in the building sector. Specially, it is very important to reduce energy through the remodeling process at deteriorated school buildings which were built over 20 years ago and sharply changed into the excessive energy consumption structure from new educational curricula. Thus, this paper examined the effects of potential factors to reduce energy at deteriorated elementary school buildings using the energy simulation on the Visual DOE 4.0 program. Among applied factors of insulations, southern louver, window's SHGC, indoor setup temperature, and system efficiency, all factors except window's SHGC turned out contribute to reduce energy at the deteriorated elementary school buildings, compared with the baseline energy performance.

A Priority Based Transmission Control Scheme Considering Remaining Energy for Body Sensor Network

  • Encarnacion, Nico;Yang, Hyunho
    • Smart Media Journal
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    • v.4 no.1
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    • pp.25-32
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    • 2015
  • Powering wireless sensors with energy harvested from the environment is coming of age due to the increasing power densities of both storage and harvesting devices and the electronics performing energy efficient energy conversion. In order to maximize the functionality of the wireless sensor network, minimize missing packets, minimize latency and prevent the waste of energy, problems like congestion and inefficient energy usage must be addressed. Many sleep-awake protocols and efficient message priority techniques have been developed to properly manage the energy of the nodes and to minimize congestion. For a WSN that is operating in a strictly energy constrained environment, an energy-efficient transmission strategy is necessary. In this paper, we present a novel transmission priority decision scheme for a heterogeneous body sensor network composed of normal nodes and an energy harvesting node that acts as a cluster head. The energy harvesting node's decision whether or not to clear a normal node for sending is based on a set of metrics which includes the energy harvesting node's remaining energy, the total harvested energy, the type of message in a normal node's queue and finally, the implementation context of the wireless sensor network.

Assessment of Potentiality of Renewable Energy Based Urban Forms (도시 형태에 따른 신재생에너지 잠재성 평가에 관한 연구)

  • Jung, A-Rum;Chung, Min-Hee;Rhee, Eon-Ku
    • Journal of the Korean Solar Energy Society
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    • v.30 no.2
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    • pp.22-32
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    • 2010
  • The world is facing environmental problem described as climate change and exhaustion of fossil fuel. In order to solve theses problems, importance of renewable energy is extremely growing. For stable energy supply, it is need to apply hybrid renewable energy systems in urban-scale, because some renewable energy system' outputs are greatly influenced by climatic condition. Especially, solar irradiation and wind velocity are influenced by urban geometric environment as well as climatic condition. Therefore it is necessary to evaluate the renewable energy potential according as urban form. This study aims to evaluate the potential of solar energy and wind energy in urban-scale and classify urban type according as characteristics of urban forms. The results of this study will be used to develop renewable energy system application guidelines for urban and energy planning.

Analysis of Biomass Energy Potential around Major Cities in South Korea (국내 주요도시 주변의 바이오매스 에너지 잠재량 분석)

  • Kook, Jin Woo;Lee, See Hoon
    • Applied Chemistry for Engineering
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    • v.26 no.2
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    • pp.178-183
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    • 2015
  • Biomass is recognized as one of important renewable energy sources because it can be converted and used as solid, gaseous and liquid forms. Also, biomass is one of promising ways to solve the depletion of fossil fuels and global warming problems. The information about local biomass energy potentials and space energy densities can be powerfully utilized to determine the scale of biomass energy conversion plant and to analyze economic effects. The latest data on domestic biomass resources, such as agricultural, forestry, livestock and urban wastes, were collected from various government organizations and institutes and were analyzed to calculate biomass energy potential and space energy density. As local areas in South Korea to collect biomass resources increased, energy potentials increased, but space energy densities of total biomass decreased.