• 대한전기학회논문지
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• 제33권1호
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• pp.9-16
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• 1984

This paper describes the minimum cost expansion planning which is based on the economical aspect under the various conditions on the power system expansion planning. It presents not only linear cost characteristics analysis but also stepwise cost characteristics analysis which satisfies practical condition in the power system. The latter analysis must be handled by integer programming (IP), because the relation between the cost and the capacity has stepwise characteristics. In order to proceed the latter analysis, the solving procedure is illustrated in detais by using branch and bound method which includes the network flow theory and maximum flow-minimum cut theorem.

• 대한산업공학회지
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• 제19권2호
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• pp.43-51
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• 1993

This paper describes the flow path design of unidirectional automated guided vehicle systems. The objective is to find the flow path which will minimize total travel time of unloaded as well as loaded vehicles. The allocation of unloaded vehicles is determined by applying the transportation simplex method. The problem is solved using a branch-and-bound technique. A simple illustrative example is discussed to demonstrate the procedure.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2005년도 High Temperature Superconductivity Vol.XV
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• pp.31-31
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• 2005

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제2권5호
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• pp.217-222
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• 2013

Return-Oriented Programming(ROP)는 기존 return-to-libc의 발전된 형태로 프로그램의 코드 영역에 있는 가젯을 조합하여 공격자가 원하는 모든 기능을 수행할 수 있는 코드 재사용 공격 기법이다. ROP 공격을 방어하는 기존 방어 기법들은 동적 실행 흐름 분석으로 인한 높은 성능 부하를 보이거나 ROP 공격에 대한 부분적인 방어만 가능하였다. 본 논문에서 제시하는 간접 분기 목적 주소 검증 기법(Indirect Branch Target Address Verification)은 간접 분기문의 목적 주소가 유효한지 검사해서 ROP 공격을 탐지하며, ROP 공격의 대부분을 방어할 수 있다. 또한 동적 실행 흐름 분석이 필요 없기 때문에 낮은 성능 부담을 보인다. SPEC CPU 2006 벤치마크를 대상으로 한 성능평가에서 15%보다 적은 성능 부하를 보였다.

• 디지털콘텐츠학회 논문지
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• 제3권2호
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• pp.221-233
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• 2002

본 논문에서는 용량제약이 있는 설비의 위치선정 및 수요자 할당 문제(Capacitated Facility Location-Allocation Problem)에 대한 정수계획 모형과 해법을 제시하였다. 이 문제는 설비를 설치할 수 있는 후보지의 집합과 각 후보지별로 설치 가능한 설비의 용량 및 설치비용, 수요를 만족시켜야 할 수요자의 집합 및 각 수요자와 설치 후보지 사이의 운반비용이 주어져 있을 때, 설비들의 설치비용과 수요의 운반비용의 합을 최소화하는 설비의 설치 위치 및 대수 그리고 수요자와 설비간의 연결상태를 구성하는 문제이다. 본 논문에서는 이 문제에 대한 두 가지 정수계획모형을 제시하고, 이 모형에 대한 최적해를 구하기 위한 다면체적 절단평면을 이용한 분지-절단해법(Branch-and-cut algorithm)과 열생성기법을 이용한 분지-평가해법(Branch-and-Price algorithm)을 제시하였다. 제시된 모형과 해법은 물류시스템의 설계 및 정보통신시스템의 통신설비 위치선정 등에 활용될 수 있다.

• 한국유체기계학회 논문집
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• 제20권1호
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• pp.53-58
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• 2017

This paper describes liquidity evaluation on the horizontal branch pipe connected to a food waste disposer and performance of five disposers marketed. Experimental apparatus for analyzing the five disposers has been introduced to measure vibration, sound level and power consumption of the disposers. Simulator for analyzing the required water velocity to avoid waste jam inside the pipe connected to a food waste disposer has been designed and constructed. The simulator can control some experimental parameters: pipe slope, disposer supply water quantity, food waste materials and operation time of a disposer. Throughout the experimental measurements of the disposers marketed, it is found that the time need to crash food waste is about 20 seconds on the average. At the same flow condition, increase rate of internal water velocity is accelerated as the pipe slope increases. The water velocity inside the pipe having 50 A and slope of 1/50 is 0.26 m/s when the water flowrate to supply the disposer is 16 l pm. Considering the specific gravity and adhesion property of food waste, water velocity of the horizontal branch pipe connected to a food waste disposer need to excess 0.26 m/s at least to avoid the waste blockage inside the pipe.

• 한국결정성장학회지
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• 제24권1호
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• pp.1-7
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• 2014

질화알루미늄(AlN)은 뛰어난 열적, 전기절연성 특성을 갖고 있어 반도체 기판용 재료나 전자 패키징 재료로 주목받고 있다. 질화알루미늄은 소결온도가 높고 불순물로 인한 물성저하 때문에 고순도화 및 나노원료화가 필수적이다. 본 연구에서는 RF 유도결합 열플라즈마를 이용하여 알루미늄 분말로부터 고순도의 질화알루미늄 나노분말을 합성하였다. Sheath gas로 사용된 암모니아의 유량 제어를 통해 고순도의 질화알루미늄 나노분말이 합성되는 조건을 확립하고자 하였으며 합성된 분말은 XRD, SEM, TEM, BET, FTIR, N-O분석을 통해 특성분석을 진행하였다.

• 한국세라믹학회지
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• 제48권3호
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• pp.236-240
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• 2011

In order to deposit a homogeneous and uniform ${\beta}$-SiC films by chemical vapor deposition, we demonstrated the phase stability of ${\beta}$-SiC over graphite and silicon via computational thermodynamic calculation considering pressure, temperature and gas composition as variables. The ${\beta}$-SiC predominant region over other solid phases like carbon and silicon was changed gradually and consistently with temperature and pressure. Practically these maps provide necessary conditions for homogeneous ${\beta}$-SiC deposition of single phase. With the thermodynamic analyses, the CVD apparatus for uniform coating was modeled and simulated with computational fluid dynamics to obtain temperature and flow distribution in the CVD chamber. It gave an inspiration for the uniform temperature distribution and low local flow velocity over the deposition chamber. These calculation and model simulation could provide milestones for improving the thickness uniformity and phase homogeneity.

• 대한기계학회논문집
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• 제19권12호
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• pp.3360-3371
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• 1995

Hydrodynamic characteristics of a stratified flow at a Y-junction were examined analytically. Gas is supplied through the main horizontal channel and liquid is introduced into the gas stream from the Y-shaped bottom branch. Analysis was performed with irrational flow and inviscid fluid assumptions. The Stokes' inverse transformation technique was adopted to convert the real x-y plane into the x-.psi. plane. The potential flow equation was solved numerically in the transformed (x-.psi.) plane and the interface profile, pressure distribution and the streamlines were obtained. The effects of the inlet conditions, injection angle and the gravity on the flow characteristics were also examined. To check the validity of the present method, the previous resultant the two-dimensional obtuse wedge flow was compared. The inverse transformation technique turned out to be also very useful to predict the hydrodynamic characteristics of a stratified flow with the pressure variation at a Y-shaped mixing junction.

• 상하수도학회지
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• 제13권3호
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• pp.73-82
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• 1999

In this study, the optimal analysis for pipe network is performed for the combined ideal pipe network system(CASE 1, CASE 2 and CASE 3) which is composed of 25 nodes, 41 elements, and 1 fixed nodal head with evaluating pressure variation distribution of main and branch in grid composed drainage pipe network. The linear analysis technique used as the analysis method in this study, the KYPIPE being used extensively as the linear technique to design and analysis of pipe network is applied. Firstly, in the analysis of pipe network, the CASE 2 and CASE 3 supply same thing(value) in the result of considering the total flow provided each pipeline, but in the general intension in the case of CASE 2, relative width of supply is more large than CASE 1 and CASE 3. Secondly, in the analysis technique of pipe network, CASE 3 is analysed largest as a result of comparing with same heads, and in the order of their size CASE 2 and CASE 1 were determined but the difference doesn't appear to be obvious. Thirdly, as the result of determining main factor, pressure in the design and analysis of net work. CASE 3 is from Node 3 to 25 than CASE 1 and CASE 2 and it is determined in the order of their size, CASE 2 and CASE 1. Finally, in this study, discharge flow distribution is evaluated in the same condition with 3-type CASE in the case of branch position for designing optimal composed drainage pipe network. As the result of that, branch pipe perform. Therefore, it is thought that the efficient and reasonable management of water supply and sewerage design will be possible if it give all our energies to study at the pipe system design in and out of country in the future.