• 한국지능시스템학회:학술대회논문집
• /
• 한국지능시스템학회 2007년도 추계학술대회 학술발표 논문집
• /
• pp.71-74
• /
• 2007

오늘날 자연재해 발생 빈도수가 증가하고 있어 ESP(Energy Service Provider)와 대수용가에 서는 예기치 못한 정전 및 에너지 중단과 같은 이벤트가 발생하면 재산상의 손실과 같은 피해가 커지고 있다. 이에 에너지 포털 시스템에서 발생활 수 있는 다양한 이벤트들을 실시간으로 처리할 수 있는 효율적인 이벤트 모델링 개발이 필요하다. 그러나 현재 이러한 이벤트 처리를 위한 이벤트 모델링 개발은 거의 이루어지고 있지 않다. 이에 본 논문에서는 에너지 포털 시스템에서 발생하는 정전과 같은 이벤트와 원격 검침 둥과 같은 부가 서비스를 제공함에 따라 발생하는 이벤트들을 지능을 가진 실시간 에이전트를 사용하여 웹 환경에서 W3C 이벤트 처리 권고안인 DOM 모델을 기반으로 esXML(energy system eXtensible Markup Language)을 사용하여 효율적으로 처리할 수 있는 모델링을 개발하였다.

• 전기학회논문지
• /
• 제58권7호
• /
• pp.1263-1269
• /
• 2009

Stable and sustainable power supply means maintaining a certain level of power quality and service while securing energy resource and resolving environmental issues. Distributed generation (DG) has become an essential and indispensable element from environmental and energy security perspectives. It is known that voltage violation is the most important constraint for load variation and the maximum allowable DG. In distribution system, sending voltage from distribution substation is regulated by ULTC (Under Load Tap Changer) designed to maintain a predetermined voltage level. ULTC is controlled by LDC (Line Drop Compensation) method compensating line voltage drop for a varying load, and the sending voltage of ULTC calls for LDC parameters. The consequence is that the feasible LDC parameters considering variation of load and DG output are necessary. In this paper, we design each LDC parameters determining the sending voltage that can satisfy voltage level, decrease ULTC tap movement numbers, or increase DG introduction. Moreover, the maximum installable DG capacity based on each LDC parameters is estimated.

• Journal of Power Electronics
• /
• 제9권6호
• /
• pp.919-928
• /
• 2009

Microgrids (MGs) are typically comprised of distributed generators (DGs) including renewable energy sources (RESs), storage devices and controllable loads, which can operate in either interconnected or isolated mode from the main distribution grid. This paper introduces a novel dynamic programming (DP) approach to MG optimization which takes into consideration the coordination of energy supply in terms of heat and electricity. The DP method has been applied successfully to several cases in power system operations. In this paper, a special emphasis is placed on the uncontrollability of RESs, the constraints of DGs, and the application of demand response (DR) programs such as directed load control (DLC), interruptible/curtaillable (I/C) service, and/or demand-side bidding (DSB) in the deregulated market. Finally, in order to illustrate the optimization results, this approach is applied to a couple of examples of MGs in a certain configuration. The results also show the maximum profit that can be achieved.

• International Journal of Concrete Structures and Materials
• /
• 제18권3E호
• /
• pp.207-211
• /
• 2006

This paper presents an experimental study on the repair performance of sprayed engineered cementitious composites(ECC) serving as a repair material. Sprayable ECC, which exhibit tensile strain-hardening behavior in the hardened state and maintain sprayable properties in the fresh state, have been developed by using a parallel control of micromechanical design and rheological process design. The effectiveness of sprayable ECC in providing durable repaired structures was assessed by spraying the ECC and testing them for the assessment. The experimental results revealed that, when sprayed ECC were used as a repair material, both load carrying capacity and ductility represented by the deformation capacity at peak load of the repaired flexural beams were obviously increased compared to those of commercial prepackaged mortar(PM) repaired beams. The significant enhancement in the energy absorption capacity and tight crack width control of the ECC repair system treated with wet-mix spraying process suggests that sprayed ECC can be effective in extending the service life of rehabilitated infrastructures.

• 전력전자학회논문지
• /
• 제20권4호
• /
• pp.344-350
• /
• 2015

A battery management system requires accurate information on the battery state of charge (SOC) to achieve efficient energy management of electric vehicle and renewable energy systems. Although correct SOC estimation is difficult because of the changes in the electrical characteristics of the battery attributed to ambient temperature, service life, and operating point, various methods for accurate SOC estimation have been reported. On the basis of piecewise linear (PWL) modeling technique, this paper proposes a simple SOC observer for lithium-polymer batteries. For performance evaluation, the SOC estimated by the PWL SOC observer, the SOC measured by the battery-discharging experiment and the SOC estimated by the extended Kalman filter (EKF) estimator were compared through a PSIM simulation study.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2016년도 추계학술대회
• /
• pp.900-903
• /
• 2016

건물, 공장, 사무실, 대형마트 등 다양한 분야에서 에너지 절감이나 사용자의 편의성 제공을 위한 센서 설치를 통해서 다양한 측정값을 서버까지 송수신하고 사용자 편의성을 고려하는 서비스가 증가하는 추세이다. 본 논문에서는 다양한 전력 사용량을 측정하는 디지털 전력량계의 데이터에 대해 - 오라클 서버와 시계열 데이터베이스 연동 및 데이터 분석을 위해- 실시간 시계열 데이터 처리에 대해서 논하고자 한다. 본 논문을 통해서, 다양한 분야에 센서 네트워크와 실시간 데이터 처리를 접목하는데 손쉽게 접근할 수 있을 것으로 기대한다.

• 한국정보처리학회:학술대회논문집
• /
• 한국정보처리학회 2007년도 춘계학술발표대회
• /
• pp.544-546
• /
• 2007

본 연구에서는 전력부가서비스 시스템으로 개발한 전력에너지 컨설팅 시스템의 주요 기능과 운영방을 소개한다. 본 시스템의 주요 기능은 전력소비 데이터 분석, 전력사용량 분석, 전력요금 분석, 전력요금 컨설팅 보고서 제공 등 4가지로 구분할 수 있다. 원격검침을 시행중인 고압고객 중 계약전력이 100kW 이상인 대수용가로부터 특히, 전력요금 절감을 필요로 하지만 별도의 설비나 인력을 보유하지 않은 10,000kW 이하 고객을 적용대상으로 하고 있다. 본 시스템은 수용가에게는 전력요금 절감을 전력회사 및 Energy Service Provider에게는 간접적 부하/수요관리 효과를 목표로 개발하였으며, 향후 대수용가를 대상으로 전력부가서비스 적용 사업화 분야에 활용될 수 있을 것이다.

• 한국통신학회논문지
• /
• 제34권4B호
• /
• pp.319-328
• /
• 2009

IEEE 802.16e 표준에서는 이동 단말의 제한된 에너지를 효율적으로 관리하기 위하여 서비스의 종류에 따라 서로 다른 수면모드 작동기법을 정의하고 있다. 기존의 수면모드 작동기법에 대한 연구는 이동 단말이 하나의 서비스를 받는 환경으로 제한되어 있으므로, 여러 서비스를 동시에 받을 경우 서로 다른 수면모드 작동기법을 동시에 적용하여 실제로 에너지를 절약하는 구간을 크게 감소시킨다. 본 논문에서 제안하는 에너지 절약 기법은 이동 단말이 여러 서비스를 동시에 받는 환경에서 실제로 에너지를 절약하는 구간을 증가시킴으로써, 에너지 소모를 최소화하고 기존과 비슷한 수준의 QoS(Quality of Services)를 보장한다. 향후 IEEE 802.16e 시스템에서 이동 단말의 제한된 배터리 수명을 증가시키면서 QoS를 보장하고 싶을 경우, 본 논문에서 제안한 에너지 절약 기법이 유용하게 사용될 수 있을 것이다.

• 수산해양기술연구
• /
• 제51권3호
• /
• pp.321-332
• /
• 2015

In an attempt to find the improvement of the fishing efficiency according to the hull form remodeling for the 3 tuna purse seiner, the Catch-Per-Unit-Effort (CPUE) for that undertaken before (2008) and after (2010) was analyzed. In addition, the CPUE of 6 similar ships operated same period and same fishing ground. As result, it came to verify that the three modified ships had a significant value on the CPUE. An another index for the improvement of fishing efficiency is the rate of reduction of fuel oil consumption for the modified ships. Fuel oil consumption per day in service speed as comparing with the original ships were reduced 2.1%, 4.0% and 5.1% on the modified ship A, B, and C respectively. And each ship's service speed was increased 1.0 kt, 0.6 kt, and 0.4 kt according to the modified ship A, B, and C in due order. In the conclusion, the remodeling job with newly equipped bulbous bow, lengthened slipway and enlarged rudder area were improved fairly much on fuel oil efficiency, the ship's speed, and in the end, that led to the improving fishing efficiency. Hence, the remodeling of tuna purse seiner come to improve not only the fishing performance, but contribute to the reduction of operating cost by saving energy for the fisheries industry.

• 한국IT서비스학회지
• /
• 제16권4호
• /
• pp.223-234
• /
• 2017

The audible pedestrian signal (APS) is an add-on device which connects to the pedestrian signaling device and informs the contents and changes of the signaling by sound. It provides walking direction information of the pedestrian crossing so that the blind people can safely cross the pedestrian crossing. In an intersection where a plurality of audible pedestrian signal (APS) are installed at an intersection crosswalk, existing audible pedestrian signal (APS) operate simultaneously in the communication radius of a wireless remote controller, which may cause confusion for the blind people and the public may complain about the noise. In this paper, we developed a BLE (Bluetooth Low Energy)-based audible pedestrian signal (APS) system capable of supporting two-way communications with a smart-phone that can cross the intersection safely and improve the walking comfort and traffic safety for the blind people. The proposed method is a method in which the BLE beacon communication based audible pedestrian signal (APS) presents active service to the blind people, and the existing audible pedestrian signal (APS) is a way of requesting the passive service by the blind people with the wireless remote control by the unidirectional communication based on 358Mhz. The developed system is installed in the crossroad of Doma-dong, Seo-gu, Daejeon, and it is tested and operated by the blind people. The satisfaction evaluation and analysis of the audible pedestrian signal (APS) for the blind people have good results and are planned to be expanded in the future.