• Title/Summary/Keyword: 에너지 정의

Search Result 2,864, Processing Time 0.036 seconds

Best Practices and Implications of Global Energy Saving Policies (세계 에너지절약정책 모범사례와 시사점)

  • Lim, Ki Choo
    • Journal of Energy Engineering
    • /
    • v.26 no.1
    • /
    • pp.45-53
    • /
    • 2017
  • The best practices of energy efficiency were selected by reviewing cases collected from the results of IEA research and prior studies, and then by evaluating the correspondence of each case for four attributes including economic performance, synergy, political adjustment, and marketability. The selected best practices included 36 cases in 6 fields such as governance, finance, utility, home, transportation, and industry/small and medium-sized businesses. The reduction of energy costs has brought countries implementing best practices of energy efficiency a variety of benefits, including higher rate of return, the reduction of incidental expenses, the increase of productivity, and the improvement of accessibility to energy. To have similar effects, other countries need to adjust these best practices before applying to their situations.

Process Optimization of Red Pepper Drying for the Improvement of Drying Efficiency (건조효율 향상을 위한 고추건조공정의 최적화)

  • Chung, Sun-Kyung;Keum, Dong-Hyuk;Lee, Dong-Sun
    • Korean Journal of Food Science and Technology
    • /
    • v.24 no.5
    • /
    • pp.428-439
    • /
    • 1992
  • Drying process in a fixed bed red pepper dryer was modeled and simulated. Drying efficiency describing the effectiveness of energy usage in red pepper drying was defined as a ratio of energy used for moisture evaporation to total energy consumption, and expressed in combination of measurable temperature variables. The efficiency was compared with real evaporative efficiency and tested in the simulated and experimental drying. An overall drying efficiency was derived, and analyzed for various control variables consisting of drying temperature, air recycle ratio and air flow rate. Optimal operation conditions of drying was then searched by Box's complex method by using it as an objective function. Carotenoids retention was simulated and put as a constraint of product quality in the optimization. The optimization results gave that two staged drying operation could improve the ding efficiency compared with single staged drying. As a technique for further energy saving automatic termination of drying appeared feasible by monitoring an exit air temperature from dryer.

  • PDF

A study on the way on energy efficiency of regenerative braking (전력회생 브레이크의 에너지 효율화 방안 연구)

  • Park, Young-Jin;Moon, Kwan-Il;Shin, Min-Sik;Son, Young-Jin
    • Proceedings of the KSR Conference
    • /
    • 2010.06a
    • /
    • pp.204-212
    • /
    • 2010
  • Currents which are generated at both ends of drive motor by operating brake pedal when subway train is driving, will generate the reviltalization actual effect if they are not used immediately. So there exist rolling stock established Dynamic braking annex for the purpose of stable brake performance in case there are no retrogress train around or no stable wiring voltage.Therefore 55% of entered energy are consumed in subway train. 45% are used in down gradient section or for regeneration energy and among them 25% are used for another train's retrogression through the wiring. So to reduce reviltalization method keeping the existing system, substation's service voltage should be declined about 5%. And then it will ease off excessive wiring voltage rise. And there need energy reduction by flexible service voltage adjustment and study for energy consumption efficiency in the subway.

  • PDF

Asynchronous Key Management for Energy Efficiency over Wireless Sensor Network (유비쿼터스 센서네트워크에서 에너지효율을 고려하는 비동기적인 키관리 기법)

  • Yoon, Mi-Youn
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.31 no.10C
    • /
    • pp.1011-1022
    • /
    • 2006
  • WSN(Wireless Sensor Network) performs to detect and collect environmental information for one purpose. The WSN is composed of a sink node and several sensor nodes and has a constraint in an aspect of energy consumption caused by limited battery resource. So many required mechanisms in WSN should consider the remaining energy condition. To deploy WSN, tile collected information is required to protect from an adversary over the network in many cases. The security mechanism should be provided for collecting the information over the network. we propose asynchronized key management considering energy efficiency over WSN. The proposed key management is focused on independence and difference of the keys used to deliver the information over several routes over the network, so disclosure of any key does not results in exposure of total key information over the overall WSN. Also, we use hash function to update key information for energy efficiency Periodically. We define the insecurity for requested security Properties and Proof that the security properties are guaranteed. Also, we evaluate and analyze the energy efficiency for the proposed mechanism.

A Study on the Energy Planning Technique of Smart Green City : Focus on Application Condition in Multi-functional Administrative City, Korea (에너지 측면의 스마트 그린시티 계획기법에 관한 연구 : 행복도시의 적용실태를 중심으로)

  • Oh, Deog-Seong;Park, So-Yeon;Lee, Seo-Jeong
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.16 no.9
    • /
    • pp.6368-6375
    • /
    • 2015
  • The goal of this research is to identify the energy planning techniques of Smart Green City and to establish the realized plan through the analysis of Multi-functional Administrative City. For the research, eighteen planning techniques were derived and categorized into three sectors and six basic direction through literature review and Brain-storming analysis considering correlation between three goals of Smart Green City and expectation of planning technique. And Multi-functional Administrative City was analyzed for the current status of application of planning techniques focus on two application aspects. In conclusion, 'Establishing Integrated Management Center for Urban Energy', 'Building Energy Management System', 'Building Automation System', 'Green Transport System', 'Intelligent Transport System', 'Introduction of Eco-friendly Transportation' planning techniques in reduction of building energy consumption sector and green-intelligent transport system sector were identified as important techniques for Smart Green City.

Stress-strain Model of Laterally Confined High-strength Concrete with the Compressive Fracture Energy (압축파괴에너지를 도입한 횡구속 고강도 콘크리트의 응력-변형률 모델)

  • Hong, Ki-Nam;Shim, Won-Bo
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.23 no.1
    • /
    • pp.54-62
    • /
    • 2019
  • In this paper, a stress-strain model for high-strength confined concrete is proposed using compressive fracture energy. In the compression test performed by author in Reference [6], an acrylic bar with strain gauges was embedded in the center of the specimen to measure the local strain distribution. It was found from the test that the local strain measurement by this acrylic rod is very effective. The local fracture zone length was defined based on the local strain distribution measured by the acrylic rod. Specifically, it was defined as the length where the local strain increases more than twice of the strain corresponding to maximum stress. In addition, the stress-strain relationship of confined concrete with compressive fracture energy is proposed on the assumption that the amount of energy absorbed by the compressive members subjected to the given lateral confining pressure is constant regardless of the aspect ratio and size. The proposed model predicts even results from other researchers accurately.

Integrated Analytical-Numerical Approach to Compute the Energy on Rock-fall Protection Fence (해석적-수치해석적 방법을 통한 낙석방지울타리에 작용하는 에너지 분석)

  • Kim, Hee Su;Hwang, Youngcheol;Jang, Hyun-Ick;Ban, Hoki
    • Journal of the Korean GEO-environmental Society
    • /
    • v.20 no.12
    • /
    • pp.57-64
    • /
    • 2019
  • A man-made slope has been increased due to the construction of road. This slope lies at risk of rock falling, induced mostly by heavy rainfall. The MOLIT (Ministry of Land, Infrastructure and Transport) recommends the specific dimension of rockfall protection fence (post, wire-rope, and mesh) which should resist 48~61 kJ. However, the energy absorption capacity of each component of rockfall protection fence is not clearly presented. Hence, this study made an effort to compute the energy absorption capacity of each component in analytical and numerical method, and compared with each other.

The study of relationship between the concentrations of Bisphenol A and DEHP in human plasma and precocious puberty (Bisphenol A와 DEHP의 혈중농도와 성조숙증 환아와의 상관성에 관한 연구)

  • Han, Eunjung;Yim, Okkyoung;Chung, Jaeyeon;Baek, Sunyoung;Kim, Yunje
    • Analytical Science and Technology
    • /
    • v.21 no.5
    • /
    • pp.375-382
    • /
    • 2008
  • Bisphenol A (BPA) and di-2-ethyhexyl phthalate (DEHP) is the considerably hazardous materials, endocrine disrupting chemicals (EDCs), which is accumulated to the human's fat and tissue. We studied the relationship between the concentrations of BPA and DEHP in the precocious puberty and the normal controls using GC/MSD. BPA concentrations of the precocious puberty are lower than that of normal controls. But DEHP concentrations of the precocious puberty are higher than that of normal controls. From these results, BPA is not related to the precocious puberty. Otherwise, DEHP is somewhat related to the precocious puberty and the concentrations of the precocious puberty are approximately 45% higher than that of normal controls.

Bayesian Image Restoration Using a Continuation Method (연속방법을 사용한 Bayesian 영상복원)

  • Lee, Soo-Jin
    • The Journal of Engineering Research
    • /
    • v.3 no.1
    • /
    • pp.65-73
    • /
    • 1998
  • One approach to improved image restoration methods has been the incorporation of additional source information via Gibbs priors that assume a source that is piecewise smooth. A natural Gibbs prior for expressing such constraints is an energy function defined on binary valued line processes as well as source intensities. However, the estimation of both continuous variables and binary variables is known to be a difficult problem. In this work, we consider the application of the deterministic annealing method. Unlike other methods, the deterministic annealing method offers a principled and efficient means of handling the problems associated with mixed continuous and binary variable objectives. The application of the deterministic annealing method results in a sequence of objective functions (defined only on the continuous variables) whose sequence of solutions approaches that of the original mixed variable objective function. The sequence is indexed by a control parameter (the temperature). The energy functions at high temperatures are smooth approximations of the energy functions at lower temperatures. Consequently, it is easier to minimize the energy functions at high temperatures and then track the minimum through the variation of the temperature. This is the essence of a continuation method. We show experimental results, which demonstrate the efficacy of the continuation method applied to a Bayesian restoration model.

  • PDF