• 에너지공학
• /
• 제17권3호
• /
• pp.145-152
• /
• 2008

에너지가격의 인상과 고갈의 시대에 들면서, 사회적으로 에너지 정책에 대한 정부의 개입요구가 더욱 높아지고 있다. 에너지 정책 시행은 양면의 상반된 효과를 유발할 수 있다. 우선 긍정적인 면에서 에너지 수입의 감소를 통해 불필요한 외화유출을 방지할 수 있어 재원의 적절한 배분을 가능케 하고, 비싼 에너지 사용의 절약을 통해 가격 경쟁력을 제고할 수 있을 것이다. 이에 반해 무분별한 에너지 절약 정책의 경우, 투입재를 에너지에서 설비로 비합리적으로 대체하여 정책실적만 기록할 뿐이고 오히려 경제에서는 생산성을 저해하는 예기치 못한 부정적인 효과를 초래할 수도 있다. 에너지 정책에서 정책효과를 높이기 위해서는 경제를 구성하는 각 산업 부문별로 에너지 사용 형태를 분석하고 그 결과를 이해하는 노력이 선행되어야 한다. 이 점에서 본 연구는 거시적 접근법의 대표적 방법인 에너지 산업연관분석을 이용해 한국의 산업 부문별 에너지 소비행태를 분석하였다. 이를 통해 에너지 사용 집약도와 에너지원별 소비행태의 변화에 대한 계량적 분석을 수행하였다.

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

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제15권6호
• /
• pp.1957-1980
• /
• 2021

The significant aim of this research has always been to evaluate the mechanism for efficient and inherently aware usage of vitality in-home devices, thus improving the information of smart metering systems with regard to the usage of selected homes and the time of use. Advances in information processing are commonly used to quantify gigantic building activity data steps to boost the activity efficiency of the building energy systems. Here, some smart data mining models are offered to measure, and predict the time series for energy in order to expose different ephemeral principles for using energy. Such considerations illustrate the use of machines in relation to time, such as day hour, time of day, week, month and year relationships within a family unit, which are key components in gathering and separating the effect of consumers behaviors in the use of energy and their pattern of energy prediction. It is necessary to determine the multiple relations through the usage of different appliances from simultaneous information flows. In comparison, specific relations among interval-based instances where multiple appliances use continue for certain duration are difficult to determine. In order to resolve these difficulties, an unsupervised energy time-series data clustering and a frequent pattern mining study as well as a deep learning technique for estimating energy use were presented. A broad test using true data sets that are rich in smart meter data were conducted. The exact results of the appliance designs that were recognized by the proposed model were filled out by Deep Convolutional Neural Networks (CNN) and Recurrent Neural Networks (LSTM and GRU) at each stage, with consolidated accuracy of 94.79%, 97.99%, 99.61%, for 25%, 50%, and 75%, respectively.

• 한국태양에너지학회 논문집
• /
• 제34권4호
• /
• pp.1-7
• /
• 2014

The microgrid system is the combination of photovoltaic(PV) array, load, and battery energy storage system. The control strategies were defined as multi-modes of operation, including rest operation without use of battery, power charging, and power discharging, which enables grid connected mode or islanded mode. Photovoltaic power is a problem of the uniformity of power quality because the power generated from solar light is very sensitive to variation of insolation and duration of sunshine. As a solution to the above problem, energy storage system(ESS) is considered generally. There fore, in this study, we did basic research activities about optimization method of the amount of energy used, using a smart microgrid test-bed constructed in building. First, we analyzed the daily, monthly and period energy pattern amount of power energy used, and analyzed PV power generation level which is built on the roof. Utilizing building energy pattern analysis data, we was studied an efficient method of employing the ESS about building power consumption pattern and PV generation.

• 전기학회논문지
• /
• 제60권10호
• /
• pp.1823-1831
• /
• 2011

When the RPS(Renewable Portfolio Standards) becomes effective in 2012, the use of renewable energy will be dramatically increased. However, there are no production simulations and demand supply programs that reflect the characteristics of the renewable energy. This paper analyzes correlations of the domestic wind power and solar power generation pattern in different areas and those of these sources' output and load pattern. Based on the regional correlation analysis, an appropriate method that uses a average output of the renewable energy or another modeling that takes account of uncertainty could be selected. Because it's output is dependent on weather condition, we can not control the generation of renewable energy, that is the reason why the correlation between the load and output pattern of sources can be helpful to determine whether the renewable energy is modeled as a generator or load modifier. Through this analysis, a basis will be provided in order to properly model the renewable energy source.

• 한국태양에너지학회:학술대회논문집
• /
• 한국태양에너지학회 2009년도 춘계학술발표대회 논문집
• /
• pp.162-169
• /
• 2009

In summer electrical energy is consumed in very high rate. It is used to operate conventional air conditioning system. Hot and humid air can germinate mould spores, encourage ill health, and create physiological stress (discomfort). Dehumidifier solar cooling effect is the one alternative solution saving electrical energy. We use surplus heat energy in the summer, to get cooling effect and then to get human reach to comfort condition. These devices have two system, dehumidifier and regeneration system. This paper will be focus in dehumidifier system. Dehumidifier system use for absorbing moisture in the air and decreasing air temperature. When the liquid desiccant as strong solution contact with the vapor air in the packed tower, it works. The heat and mass transfer performances of flow pattern in the packed tower of dehumidifier are analyzed and compared in detail. In this experiment was introduced, the flow patterns are parallel flow and counter flow. The performance of these flow patterns will calculate from air side. Which is the best flow pattern that gave huge mass transfer rate? The proposed dehumidifier flow pattern will be helpful in the design and optimization of the dehumidifier solar cooling system.

• 대한지역사회영양학회지
• /
• 제20권2호
• /
• pp.87-95
• /
• 2015

Objectives: Maintaining a balanced diet and thus health is crucial for adolescents, and the first step for balanced diet practice is meal planning. Adolescents, however, find it difficult to plan their meals. This study thus was set out to design an easier way of planning meals for adolescent girls. Methods: A dish-based target pattern for adolescent girls was tabulated, and validity of this was examined. Meal plan applying a dish-based target pattern was prepared by 150 female middle school students, and nutritional adequacies of those meal plans were examined. Validity and adequacy were tested by energy content, energy contribution ratio, nutrient adequacy ratio (NAR), probability of nutrient inadequacy, index of nutritional quality (INQ) calculation. Results: A dish-based target pattern with 11 dish groups was validated for nutritional adequacy. Though the NAR of calcium was 0.96, the INQ of calcium was 1.00. The average energy supply from the meal plans was 2,379 kcal, higher than the estimated energy requirement of a female middle school student, but the energy contribution ratio of carbohydrates, proteins, and fats were all adequate according to the acceptable macronutrient distribution range (AMDR). NAR of all nutrients examined were 1.0, except for calcium. The NAR and INQ of calcium were 0.87 and 0.75, respectively, and the meal plans at risk for calcium inadequacy was 19.30%. Conclusions: A dish-based target pattern proposed for adolescent girls was valid, but the meal plan prepared by female middle school students using this approach was high in energy and low in calcium supply. To cut down the energy supply from the meal plan, it is necessary to recommend dishes low in fat and use low fat cooking methods. To increase the calcium supply, it is important to recommend seaweed and legume group dishes with higher Ca INQ food items.

• 한국태양에너지학회 논문집
• /
• 제39권2호
• /
• pp.57-69
• /
• 2019

Because the hospital building operates 24 hours a day, 365 days a year for treatment and restoration of patients, it has a different pattern of energy use than that of ordinary buildings. Hospitals contribute to energy consumption and have a negative environmental impact. This study aims to find how meaningful energy performance, reflecting good energy management and ECMs, can be operated for hospital buildings, a category encompassing complex buildings with different systems and large differences between them. In this study, we proposed the energy diagnosis & evaluation method and energy management process to verify energy saving through operation data based on system & facility characteristics, operation pattern and energy consumption characteristics of hospital building. Energy consumption structures were surveyed throughout 4 reference hospital in Seoul, Korea. Findings confirm that different hospital departments have hugely different energy-demand profiles. Energy efficiency and energy saving potentials are presented. The energy performance analysis can be applied to a wide range of problems in energy-system operation.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제6권6호
• /
• pp.1546-1564
• /
• 2012

Pattern-based query processing has not attracted much attention in wireless sensor network though its counterpart has been studied extensively in data stream. The methods used for data stream usually consume large memory and much energy. This conflicts with the fact that wireless sensor networks are heavily constrained by their hardware resources. In this paper, we use piece wise representation to represent sensor nodes' collected data to save sensor nodes' memory and to reduce the energy consumption for query. After getting data stream's and patterns' approximated line segments, we record each line's slope. We do similar matching on slope sequences. We compute the dynamic time warping distance between slope sequences. If the distance is less than user defined threshold, we say that the subsequence is similar to the pattern. We do experiments on STM32W108 processor to evaluate our strategy's performance compared with naive method. The results show that our strategy's matching precision is less than that of naive method, but our method's energy consumption is much better than that of naive approach. The strategy proposed in this paper can be used in wireless sensor network to process pattern-based queries.

• 전기학회논문지
• /
• 제60권8호
• /
• pp.1451-1459
• /
• 2011

Recently, low energy houses have become an essential issue globally and various subsidy programs are ongoing to penetrate. All-electric houses which are another type of low energy houses or zero carbon houses are being developed. These houses consider new & renewable energy and demand side management programs in the construction and the diffusion process because these programs are essential policies to use energy resources reasonably. This paper shows a simulation methodology to control home appliances in all-electric houses considering the electricity consumption pattern of residents. The simulation is a first step to estimate energy saving of the house in a practical manner.