• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 2009년도 공동학술대회
• /
• pp.287-288
• /
• 2009

분산발전원의 위치 변경에 따른 전력조류 및 송전전력 손실 평가를 통하여 도시차원에 적합한 발전원 설치점 선정 기법의 개발이 시급하다. 본 연구에서는 전력손실을 고려하여, 분산전원이 주변의 모선 및 선로에 미치는 영향을 최소화 할 수 있도록, 분산전원의 설치지점을 선정하는 방안을 제안한다.

• Structural Engineering and Mechanics
• /
• 제56권2호
• /
• pp.169-188
• /
• 2015

There are two types of nonlinear analysis methods for building frameworks depending on the method of modeling the plastification of members including lumped plasticity and distributed plasticity. The lumped plasticity method assumes that plasticity is concentrated at a zero-length plastic hinge section at the ends of the elements. The distributed plasticity method discretizes the structural members into many line segments, and further subdivides the cross-section of each segment into a number of finite elements. When a reinforced concrete member experiences inelastic deformations, cracks tend to spread form the joint interface resulting in a curvature distribution. The program IDARC includes a spread plasticity formulation to capture the variation of the section flexibility, and combine them to determine the element stiffness matrix. In this formulation, the flexibility distribution in the structural elements is assumed to be the linear. The main objective of this study is to evaluate the accuracy of linear flexibility distribution assumed in the spread inelasticity model. For this purpose, nonlinear analysis of two reinforced concrete frames is carried out and the linear flexibility models used in the elements are compared with the real ones. It is shown that the linear flexibility distribution is incorrect assumption in cases of significant gravity load effects and can be lead to incorrect nonlinear responses in some situations.

• 융합보안논문지
• /
• 제12권6호
• /
• pp.51-59
• /
• 2012

본 논문에서 제안하는 학습몰입모형 "BoX" 는 B-Boy들이 대회에서 우승하기 위해 분산인지(distributed cognition) 경쟁을 능동적으로 즐기는 문화에서 그 발상의 기초를 두고 있다. "Battle"은 경쟁을 의미하며 X는 본 연구에서 제안하려는 교수법 적용과목이다. 본 논문의 목적은 학습자가 높은 수준의 학습몰입 상태에서 창조적 문제해결능력을 배양하는 학습모형을 제시하는 것이다. "BoX" 구현의 핵심은 개인인지부하를 줄이는 분산인지 활동을 극대화하도록 학습자간의 경쟁질서와 통제원리를 설계하는 것이다. 두 학기의 IT교육과정에서 비교학생군의 학습 성취도를 분석한 결과, "BoX" 학습모형이 기존의 수업방식에 비해서 학습몰입도와 학습 성취도를 크게 높이는 것을 확인하였다.

• 대한조선학회지
• /
• 제13권1호
• /
• pp.17-23
• /
• 1976

Some methods of analysis of rectangular plates under distributed load of various intensity with interior supports are presented herein. Analysis of many structures such as bottom, side shell, and deck plate of ship hull and flat slab, with or without internal supports, Floor systems of bridges, included crthotropic bridges is a problem of plate with elastic supports or continuous edges. When the four edges of rectangular plate is simply supported, the double Fourier series solution developed by Navier can represent an exact result of this problem. If two opposite edges are simply supported, Levy's method is available to give an "exact" solution. When the loading condition and supporting condition of a plate does not fall into these cases, no simple analytic method seems to be feasible. Analysis of a simply supported rectangular plate under irregularly distributed loads of various intensity with internal supports is carried out by applying Navier solution well as the "Principle of Superposition." Finite difference technique is used to solve plates under irregularly distributed loads of various intensity with internal supports and with various boundary conditions. When finite difference technique is applied to the Lagrange's plate bending equation, any of fourth order derivative term in this equation produces at least five pivotal points leading to some troubles when the resulting linear algebraic equations are to be solved. This problem was solved by reducing the order of the derivatives to two: the fourth order partial differential equation with one dependent variable, namely deflection, is changed to an equivalent pair of second order partial differential equations with two dependent variables. Finite difference technique is then applied to transform these equations to a set of simultaneous linear algebraic equations. Principle of Superposition is then applied to handle the problems caused by concentrated loads and interior supports. This method can be used for the cases of plates under irregularly distributed loads of various intensity with arbitrary conditions such as elastic supports, or continuous edges with or without interior supports, and this method can also be solve the influence values of deflection, moment and etc. at arbitrary position of plates under the live load.

• 대한조선학회지
• /
• 제13권4호
• /
• pp.19-24
• /
• 1976

Some method of analysis of rectangular plates under distributed load of various intensity with all edges built in are presented in. Analysis of many structures such as bottom, side shell, and deck plate of ship hull, and flat slab, deck systems of bridges is a problem of plate with continuous supports or clamped edges. When the four edges of rectangular plate is simply supported, the double fourier series solution developed by Navier can represent an exact result of this problem. If two opposite edges are simply supported, Levy's method is available to give an "exact" solution. When the loading condition and boundary condition of a plate does not fall into these cases, no simple analytic method seems to be feasible. Analysis of a plate under distributed loads of various intensity with all edges built in is carried out by applying Navier solution and Levy's method as well as "Principle of Superposition" In discussing this problem we start with the solution of the problem for a simply supported rectangular plate and superpose on the deflection of such a plate the deflections of the plate by slopes distributed along the all edges. These slopes we adjust in such a manner as to satisfy the condition of no rotation at the boundary of the clamped plate. This method can be applied for the cases of plates under irregularly distributed loads of various intensity with two opposite edges simply supported and the other two edges clamped and all edges simply supported and this method can also be used to solve the influence values of deflection, moment and etc. at arbitrary position of plates under the live load.

• 한국차세대컴퓨팅학회논문지
• /
• 제13권5호
• /
• pp.19-28
• /
• 2017

IP보안 카메라의 보급으로 원격에서 얼굴인식을 수행함에 있어 서버의 부하를 줄이기 위한 여러 가지 방법들이 구현되고 있다. 본 논문에서는 원격지에 있는 IP 보안 카메라 영상을 얼굴검출기능이 탑재된 DSP 보드를 통해 입력 받아 얼굴검출을 수행 한 후 해당 얼굴영역 이미지를 서버로 전송하여 이를 얼굴인식 분산 처리를 통해 얼굴인식 기능을 수행한다. 결과적으로 전체적인 서버시스템 로드를 상당히 줄이는 성과와 실시간 얼굴 인식처리를 최대 256대의 카메라를 연동하면서 수행할 수 있는 장점을 가지고 있다. 이를 수행할 수 있는 기술은 분산처리 서버기술을 이용하여 한 서버 당 64채널 얼굴인식을 수행하며, 4개 분산처리 서버를 운영할 경우 250여개 카메라 채널을 통한 얼굴검출 결과를 처리하는 성과를 가져올 수 있었다.

• 통합자연과학논문집
• /
• 제16권4호
• /
• pp.139-145
• /
• 2023

Due to changes in the distribution system and increased demand for renewable energy, interest in technology to increase the limit capacity of distributed energy grid connection using grid flexible resources is also increasing. Recently, the distribution system system is changing due to the increase in distributed power from renewable energy, and as a result, problems with the limited capacity of the distribution system, such as waiting for renewable energy to connect and increased overload, are occurring. According to the power generation facility status report provided by the Korea Power Exchange, of the total power generation capacity of 134,020 MW as of 2021, power generation capacity through new and renewable energy facilities is 24,855 MW, accounting for approximately 19%, and among them, power generation through solar power accounts for a total portion of the total. It was analyzed that the proportion of solar power generation facilities was high, accounting for 75%. In the future, the proportion of new and renewable energy power generation facilities is expected to increase, and accordingly, an efficient operation plan for the distribution system is needed. Advanced country-type NWAs that can integrate the operation and management of load characteristics for each line of the distribution system, power distribution, regional characteristics, and economic feasibility of distributed power in order to improve distribution network use efficiency without expanding distribution facilities due to the expansion of renewable energy. An integrated operating system is needed. In this study, in order to improve the efficiency of distribution network use without expanding distribution facilities due to the expansion of renewable energy, we developed a method that can integrate the operation and management of load characteristics for each line of the distribution system, power distribution, regional characteristics, and economic feasibility of distributed power. We want to develop an integrated operation system for NWAs similar to that of advanced countries.

• 조명전기설비학회논문지
• /
• 제24권7호
• /
• pp.9-19
• /
• 2010

Fuel cell (FC) distributed generation (DG) is gradually becoming more attractive to mainstream electricity users as capacity improves and costs decrease. New technologies including inverters are becoming available to provide a uniform standard interconnection of DGs with an electric power system. Some of the operating conflicts and the effect of DG on power quality are addressed and investigated through simulations on a real distribution network with an FC power plant. The results of these simulations have proved load tracking capability following the real and reactive power change of the load and have shown the flow of overcurrent from an FC power plant during the ground fault of a distribution line.

• 교육녹색환경연구
• /
• 제9권1호
• /
• pp.32-40
• /
• 2010

The purpose of this study was to evaluate structural safety and economic efficiency of prestressed hybrid beam using T-shape steel member which was developed to build large span educational facilities. Hybrid beam specimens were manufactured with 16.0m long and load was uniformly distributed by 12.0kN steel hexahedrons. In this study, honeycomb beam design process was introduced to T-shape section steel beam design. Vibration condition of specimens were analyzed by Korea Building Code 2009 and AISC Steel Design Guide Series-11. As a result, the prestressed hybrid beam with T-shape steel member has about 10.4% of cost reduction effect.

• 전기학회논문지
• /
• 제60권12호
• /
• pp.2206-2214
• /
• 2011

LDC(Line Drop Compensation) is widely used in controlling ULTC(Under Load Tap Changer) output voltage at distribution substation. However, LDC may experience some difficulties in voltage control due to renewable energy resources and distributed generations. Therefore, more advanced voltage control algorithm is necessary to deal with these problems. In this paper, a modified voltage control algorithm for ULTC and DG is suggested. ULTC is operated with the voltages measured at various points in distribution system and prevents overvoltage and undervoltage in the distribution feeders. Reactive power controller in DG compensates the voltage drop in each distribution feeders. By these algorithms, the voltage unbalance between feeders and voltage limit violation will be reduced and the voltage profile in each feeder will become more flat.