• KSII Transactions on Internet and Information Systems (TIIS)
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• 제4권6호
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• pp.1133-1151
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• 2010

Energy balanced consumption routing is based on assumption that the nodes consume energy both in transmitting and receiving. Lopsided energy consumption is an intrinsic problem in low-cost sensor networks characterized by multihop routing and in many traffic overhead pattern networks, and this irregular energy dissipation can significantly reduce network lifetime. In this paper, we study the problem of maximizing network lifetime through balancing energy consumption for uniformly deployed low-cost sensor networks. We formulate the energy consumption balancing problem as an optimal balancing data transmitting problem by combining the ideas of corona cluster based network division and optimized transmitting state routing strategy together with data transmission. We propose a localized cluster based routing scheme that guarantees balanced energy consumption among clusters within each corona. We develop a new energy cluster based routing protocol called "OECR". We design an offline centralized algorithm with time complexity O (log n) (n is the number of clusters) to solve the transmitting data distribution problem aimed at energy balancing consumption among nodes in different cluster. An approach for computing the optimal number of clusters to maximize the network lifetime is also presented. Based on the mathematical model, an optimized energy cluster routing (OECR) is designed and the solution for extending OEDR to low-cost sensor networks is also presented. Simulation results demonstrate that the proposed routing scheme significantly outperforms conventional energy routing schemes in terms of network lifetime.

• 토지주택연구
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• 제11권1호
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• pp.95-101
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• 2020

In the past few decades, the global population growth and rapid economic development have resulted in significant increases in building energy consumption. To reduce greenhouse-gas emissions and building energy consumption, building materials and energy technologies must be optimized. Building retrofitting is a more efficient method than reconstruction to improve the building energy performance. In order to improve the energy performance of existing buildings, this study proposed energy-efficiency retrofit plans and derived cost-effective retrofit plan. The energy efficient retrofit method is achieved through the packaging of energy technology and the energy and cost reduction effect of the energy efficiency retrofit package are analyzed. As a result of the study, the energy-efficiency retrofit package showed an energy reduction effect of up to 60% or more and a construction cost reduction of about 30%. This study argues that optimal energy and construction cost reduction of existing buildings are possible through the packaging of energy efficiency technology.

• 드라이브 ㆍ 컨트롤
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• 제17권2호
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• pp.38-44
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• 2020

Various efforts have been initiated to reduce the energy consumption of the compressor as it is one of the approaches to saving a large portion of the fixed cost of the production site. Various results of reducing the energy consumption of the compressor have been reported, but to reduce the energy consumption of the compressors fundamentally, regular management of the compressor should ensure optimum operation. This requires periodic on-site visits by experts, but is often overlooked as a cost issue, resulting in the use of the compressor in low-efficiency conditions. Thus, it is necessary to develop a low-cost evaluation technology for compressor condition monitoring and efficiency analysis to ensure that the compressor is always driven at the optimum efficiency without imposing undue burden on the compressor user. In this study, a sensor was installed at the inlet, outlet, and power supply of the compressor, and a method for evaluating the energy consumption of the compressor using the minimum sensor was derived. The experimental results are presented to show the validity of the proposed method. It was confirmed that the energy consumption of the compressor can be easily as well as efficiently evaluated by using the method developed in this study.

• 한국농공학회논문집
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• 제50권4호
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• pp.99-109
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• 2008

As the price of traditional fossil fuels continue to increase, more people attach importance to the pollution of the environment caused by fossil fuel's burning, developing and using renewable energy resources has become a very important project all over the world. Also, the rural energy planning which is another method to improve energy utilization ratio and reduce environment pollution, is also regarded as a very effective way to reduce the energy consumption. There is a quantity of renewable energy resources and natural tribes in rural area, which is both feasible to develop the renewable energy and the regional energy planning. To carry out this, it is needs to know the area's quantity of renewable energy resources and the total energy consumption. This paper is to find out the relationship between rural energy consumption and rural conditions, and to found a energy consumption model which can conjecture the energy consumption in rural family. and the cost of rural family's energy consumption was founded to conjecture how much money dose it cost in rural family's energy consumption. The energy consumption model was concluded using the surveys of 76 families in 14 villages at the area of Chungcheongbuk-Do(province). The main factors to energy consumption was selected out which were number of family members, acreage of house, acreage of farmland and family's annual income.

• 한국콘텐츠학회논문지
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• 제18권1호
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• pp.422-430
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• 2018

최근 유가 상승과 건물 에너지 소비 증가는 에너지 자원 해외 의존도가 높은 우리나라에 큰 부담이 되고 있다. 이런 상황에서 에너지 소비량의 40% 수준을 차지하는 빌딩건물의 에너지절감은 매우 중요한 이슈가 되는데, 본 연구는 ICT를 활용하여 건물에너지 소비량 및 전력사용요금 절감을 하는 최적제어방법을 구현한 실증 분석을 병원을 대상으로 수행하였다. 먼저 기존의 냉난방용 흡수식 냉온수기와 급탕용 보일러시설 일부를 수축열 히트펌프로 대체하고 사용하는 요금제의 조정을 통해 에너지소비량을 줄이고 요금을 절감하였다. 여기에 환경(외기온도, 사용량 증감 등) 변화를 고려한 ICT 기반 최적제어 기능을 추가적으로 적용함으로 기존 설비 대체 중심의 에너지절감 방법과 ICT 기반의 최적제어방법까지 고려한 효과를 분석하였다. 그 결과 본 연구에서 병원 대상의 최적제어방법은 에너지효율화 설비 적용으로 인한 절감량(53.6%)에 최적자동제어 효과(18.2%)까지 추가적으로 절감할 수 있는 것을 확인하였다. 본 연구 결과를 바탕으로 건물 에너지 절감 성과를 높이는 다양한 방안을 검토해 볼 수 있을 것이다.

• 한국지열·수열에너지학회논문집
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• 제18권4호
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• pp.45-57
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• 2022

The Ministry of National Defense of the Republic of Korea is showing a lot of interest in net zero-energy buildings (NZEBs) to reduce energy consumption of military facilities and to promote green growth policy in military sector. The application of building passive technologies and renewable energies is essential to achieving NZEBs. This paper analyzed energy performance and energy cost on the conventional heating and cooling system (baseline scenario) and three different alternative scenarios (ALT 1, ALT 2 and ALT 3) applied in a hypothetical military building. A building modeling and simulation software (DesignBuilder V6.1) with EnergyPlus calculation engine was used to calculate the energy consumption for each scenario. Overall, when the GSHPs are applied to both space airconditioning and domestic hot water (DHW) production, Alt-2 and Alt-3, the amount of energy consumption for target building can be greatly reduced. In addition, when the building envelope performance is increased like Alt-3, the energy consumption can be further reduced. The annual energy cost analysis showed that the baseline was approximately 161 million KRW, while Alt-3 was approximately 33 million KRW. Therefore, it was analyzed that the initial construction cost increase could be recovered within about 6.7 years for ALT 3. The results of this study can help decision-makers to determine the optimal strategy for implementing GSHP systems in military buildings through energy performance and initial construction cost assessment.

• Environmental Engineering Research
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• 제21권4호
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• pp.409-419
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• 2016

As a major energy consumption province, the issue about the carbon emissions in Hebei Province, China has been concerned by the government. The carbon emissions can be effectively reduced due to a more rational energy consumption structure. Thus, in this paper the constraint of low carbon emissions is considered as a foundation and four energies--coal, petroleum, natural gas and electricity including wind power, nuclear power and hydro-power etc are selected as the main analysis objects of the adjustment of energy structure. This paper takes energy cost minimum and carbon trading cost minimum as the objective functions based on the economic growth, energy saving and emission reduction targets and constructs an optimization model of energy consumption structure. And empirical research about energy consumption structure optimization in 2015 and 2020 is carried out based on the energy consumption data in Hebei Province, China during the period 1995-2013, which indicates that the energy consumption in Hebei dominated by coal cannot be replaced in the next seven years, from 2014 to 2020, when the coal consumption proportion is still up to 85.93%. Finally, the corresponding policy suggestions are put forward, according to the results of the energy structure optimization in Hebei Province.

• 대한전기학회논문지:전력기술부문A
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• 제53권3호
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• pp.187-197
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• 2004

This paper presents a window-based load management system (LMS) developed as a decision-making tool in the competitive electricity market The developed LMS can help the users to monitor system load patterns, analyze their past energy consumption and schedule for the future energy consumption. The LMS can also provide the effective information on real-time energy/cost monitoring, consumed energy/cost analysis, demand schedule and cost-savings. Therefore. this LMS can be used to plan the optimal demand schedule and consumption strategy.

• Current Optics and Photonics
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• 제1권4호
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• pp.315-324
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• 2017

In recent years, multicast services such as high-definition television (HDTV), video conferencing, interactive distance learning, and distributed games have increased exponentially, and wavelength-division multiplexing (WDM) networks are considered to be a promising technology due to their support for multicast applications. Multicast survivability in WDM networks has been the focus of extensive attention since a single-link failure in an optical network may result in a massive loss of data. But the improvement of network survivability increases energy consumption due to more resource allocation for protection. In this paper, an energy-efficient multicast algorithm (EEMA) is proposed to reduce energy consumption in WDM networks. Two cost functions are defined based on the link state to determine both working and protection paths for a multicast request in WDM networks. To increase the number of sleeping links, the link cost function of the working path aims to integrate new working path into the links with more working paths. Sleeping links indicate the links in sleep mode, which do not have any working path. To increase bandwidth utilization by sharing spare capacity, the cost function of the protection path is defined to use sleeping fibers for establishing new protection paths. Finally, the performance of the proposed algorithm is evaluated in terms of energy consumption, and also the blocking probability is evaluated under various traffic environments through OPNET. Simulation results show that our algorithm reduces energy consumption while maintaining the quality of service.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권1호
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• pp.35-57
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• 2021

Fog computing aims to provide the solution of bandwidth, network latency and energy consumption problems of cloud computing. Likewise, management of data generated by healthcare IoT devices is one of the significant applications of fog computing. Huge amount of data is being generated by healthcare IoT devices and such types of data is required to be managed efficiently, with low latency, without failure, and with minimum energy consumption and low cost. Failures of task or node can cause more latency, maximum energy consumption and high cost. Thus, a failure free, cost efficient, and energy aware management and scheduling scheme for data generated by healthcare IoT devices not only improves the performance of the system but also saves the precious lives of patients because of due to minimum latency and provision of fault tolerance. Therefore, to address all such challenges with regard to data management and fault tolerance, we have presented a Fault Tolerant Data management (FTDM) scheme for healthcare IoT in fog computing. In FTDM, the data generated by healthcare IoT devices is efficiently organized and managed through well-defined components and steps. A two way fault-tolerant mechanism i.e., task-based fault-tolerance and node-based fault-tolerance, is provided in FTDM through which failure of tasks and nodes are managed. The paper considers energy consumption, execution cost, network usage, latency, and execution time as performance evaluation parameters. The simulation results show significantly improvements which are performed using iFogSim. Further, the simulation results show that the proposed FTDM strategy reduces energy consumption 3.97%, execution cost 5.09%, network usage 25.88%, latency 44.15% and execution time 48.89% as compared with existing Greedy Knapsack Scheduling (GKS) strategy. Moreover, it is worthwhile to mention that sometimes the patients are required to be treated remotely due to non-availability of facilities or due to some infectious diseases such as COVID-19. Thus, in such circumstances, the proposed strategy is significantly efficient.