• 한국자동차공학회논문집
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• 제11권2호
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• pp.203-210
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• 2003

A simulation study was carried to analyze the vehicle fuel consumption on component basis. Experiments was also carried out to identify the simulation results, under FTP-75 Hot Phase driving conditions. and arbitrary driving conditions. A good quantitative agreement was obtained. Based on the simulation, fuel energy was used in pumping loss(3.7%), electric power generation(0.7%), engine friction(12.7%), engine inertia(0.7%), torque converter loss(4.6%), drivetrain friction(0.6%), road-load(9.2%), and vehicle inertia(13.4%) under FTP-75 Hot Phase driving conditions. Using simulation program, the effects of capacity factor and idle speed on fuel consumption were estimated. A increment of capacity factor of torque converter resulted in fuel consumption improvement under FTP-75 Hot Phase driving conditions. Effect of a decrement of idle speed on fuel consumption was negligible under the identical driving conditions.

• 토지주택연구
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• 제1권1호
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• pp.27-34
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• 2010

본 연구에서는 그린 홈의 보급확대와 평가기법 개발을 목적으로 하고 있다. 구체적으로는 기 조사된 실측 데이터를 기본으로 시뮬레이션 결과 값의 보간 및 설비시스템의 교체에 따른 효과 검토를 통하여 에너지 절감량 및 이산화탄소 배출 삭감량 평가 프로그램을 개발하였다. 또한, 그린 홈의 보급확대에 따른 비용 검토를 통하여 그린홈을 건설하는 사업자에게는 지방세법 개정에 따른 취등록세 감면 등의 지원대책을 수립하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권8호
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• pp.3823-3840
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• 2017

This paper analyzes the nodes deployment optimization problem in energy constrained wireless sensor networks, which multi-hop cooperative beamforming (CB) based cooperative-multi-input-single-output (CMISO) transmission is adopted to reduce the energy consumption. Firstly, we establish the energy consumption models for multi-hop SISO, multi-hop DSTBC based CMISO, multi-hop CB based CMISO transmissions under random nodes deployment. Then, we minimize the energy consumption by searching the optimal nodes deployment for the three transmissions. Furthermore, numerical results present the optimal nodes deployment parameters for the three transmissions. Energy consumption of the three transmissions are compared under optimal nodes deployment, which shows that CB based CMISO transmission consumes less energy than SISO and DSTBC based CMISO transmissions. Meanwhile, under optimal nodes deployment, the superiorities of CB based CMISO transmission over SISO and DSTBC based CMISO transmissions can be more obvious when path-loss-factor becomes low.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.919-924
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• 2008

Power consumption in the building thermal load could be the sum of the building fabric conduction load, building ventilation convection load and other such as radiation loss load. Dynamic Breathing Building (DBB) is the state-of-the-art to improve the wall insulation and indoor air quality(IAQ) performance as making air flow through the wall. This heat recovery type DBB contributes the power consumption saving due to the improved dynamic U-value. KIER twin test cell with static insulation(SI) and dynamic insulation(DI) at KIER was developed to test building power consumption at the real outside conditions. Then, the actual results were compared with the theory to predict the power consumption at the KIER twin test cell and introduced the building new radiation loss factor $\alpha$ to explain the difference between the both the theory and the actual case. As the results, the power consumption at the breathing DI wall building could saved 10.8% at the 2ACH(Air change per hour) compared with conventional insulation. The building radiation loss factor $\alpha$ for this test condition to calibrate the actual test was 0.55 in the test condition.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2005년도 춘계학술대회논문집
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• pp.331-336
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• 2005

It is increased electrical energy consumption with the development of intelligence society in the office buildings and thus an energy conservation through efficient use of electricity became more important. This paper shows a reasonable design demand factor in office buildings, that was made by the systematic and statistical way considering actual conditions, such as investigated electric equipment capacity, peak power consumption, demand factor, etc., for 54 office buildings and 34 electrical design offices. In this dissertation, it is necessary to analyse the key features and general trend from the investigated data. It made an analysis of the feature parameters, such as average, standard deviation, median, maximum, minimun and thus it was carried linear and nonlinear regression analysis.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2005년도 학술대회 논문집
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• pp.233-237
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• 2005

It is increased electrical energy consumption with the development of intelligence society in the general hospitals and thus an energy conservation through efficient use of electricity became more important. This paper shows a reasonable design demand factor in office buildings, that was made by the systematic and statistical way considering actual conditions, such as investigated electric equipment capacity, peak power consumption, demand factor, etc., for 32 general hospitals and 9 electrical design offices. In this dissertation, it is necessary to analyse the key features and general trend from the investigated data. It made an analysis of the feature parameters, such as average, standard deviation, median, maximum, minimun and thus it was carried linear and nonlinear regression analysis.

• ETRI Journal
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• 제38권4호
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• pp.735-745
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• 2016

The Paris agreement at the 21st Conference of the Parties (COP21) emphasizes the reduction of greenhouse gas emissions and increase in energy consumption in all areas. Thus, an important aspect is energy saving in buildings where the lighting is a major component of the electrical energy consumption. This paper proposes a building energy management system employing visible light communication (VLC) based on LED lighting. The proposed management system has key characteristics including personalization and localization by utilizing such VLC advantages as secure communication through light and location-information transmission. Considering the efficient implementation of an energy-consumption adjustment using LED luminaires, this paper adopts variable pulse position modulation (VPPM) as a VLC modulation scheme with simple controllability of the dimming level that is capable of providing a full dimming range. This paper analyzes the VPPM performances according to variable dimming for several schemes, and proposes a VPPM demodulation architecture based on dimming-factor acquisition, which can obtain an improved performance compared to a 2PPM-based scheme. In addition, the effect of a dimming-factor acquisition error is analyzed, and a frame format for minimizing this error effect is proposed.

• 자원ㆍ환경경제연구
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• 제20권2호
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• pp.335-356
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• 2011

본 연구에서는 Markowitz (1952)의 평균-분산 모형과 지배원리에 입각하여 원유, 석탄, 천연가스로 대표되는 화석에너지원의 최적 소비조합을 구축하려 하였다. 이를 위해 1달러당 열량으로 정의된 화석에너지원들의 편익변동을 동태은닉공통인자 모형을 이용하여 동행부분과 개별 에너지원의 특이적 수급상황에 기초한 변동으로 분해한 후, 그 결과에 기초하여 최적 화석에너지원의 최적 소비조합을 구성하였다. 분석결과, 평균-분산 모형에서 최적 소비조합을 의미하는 효율적 프론티어 선상의 소비조합들에서는 사회적으로 도달 가능한 최저 수준의 원유소비 비중을 유지하면서 석탄보다는 천연가스의 소비비중을 높여야 하는 것으로 나타났다. 이와 같은 결과는 현재 우리나라에서 추구하고 있는 원유 및 석탄의 소비비중 축소전략과도 일치하는 결과라 할 수 있으며, 원유소비의 비중축소가 화석에너지원의 소비로부터 얻을 수 있는 편익향상과 함께 편익변동에 따르는 경제활동의 불안정성을 축소시킬 수 있는 방법임을 지적하는 것이라 할 수 있다.

• 전기전자학회논문지
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• 제22권3호
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• pp.747-753
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• 2018

Currently, many companies have succeeded in logistics delivery experiments utilizing drone and report it. When a drone is used commercially, long-term flight is an important performance that a drone should have. However, unlike vehicles operated on the ground, drone is a vehicle that continues to consume energy when maintaining the current altitude or moving to the destination. Therefore, the drones can fly for a long time as the capacity of the battery is large, but the batteries with large capacity are restricted by heavy weight and it acts as a limiting factor in a commercial use. To address this issue, we attempt to compare how far we can fly than forward flight based on the flight pattern with the same energy consumption condition. In this paper, the comparison of energy consumption was performed in three flight pattern, forward flight without altitude change and forward flight with altitude change, by computer simulation and it shows the increasing of flight distances when the quadrotor fly with altitude change from high altitude to low altitude.

• Journal of Information Processing Systems
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• 제17권3호
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• pp.489-504
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• 2021

By distributing computing tasks among devices at the edge of networks, edge computing uses virtualization, distributed computing and parallel computing technologies to enable users dynamically obtain computing power, storage space and other services as needed. Applying edge computing architectures to Internet of Vehicles can effectively alleviate the contradiction among the large amount of computing, low delayed vehicle applications, and the limited and uneven resource distribution of vehicles. In this paper, a predictive offloading strategy based on the MEC load state is proposed, which not only considers reducing the delay of calculation results by the RSU multi-hop backhaul, but also reduces the queuing time of tasks at MEC servers. Firstly, the delay factor and the energy consumption factor are introduced according to the characteristics of tasks, and the cost of local execution and offloading to MEC servers for execution are defined. Then, from the perspective of vehicles, the delay preference factor and the energy consumption preference factor are introduced to define the cost of executing a computing task for another computing task. Furthermore, a mathematical optimization model for minimizing the power overhead is constructed with the constraints of time delay and power consumption. Additionally, the simulated annealing algorithm is utilized to solve the optimization model. The simulation results show that this strategy can effectively reduce the system power consumption by shortening the task execution delay. Finally, we can choose whether to offload computing tasks to MEC server for execution according to the size of two costs. This strategy not only meets the requirements of time delay and energy consumption, but also ensures the lowest cost.