• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2015년도 추계학술대회
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• pp.619-622
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• 2015

최근 심각한 기후변화로 인하여 농산물 생산성 및 농산물 가격의 변동성이 커지고 있으며, 이러한 문제를 해결하기 위하여 농산물의 생산량을 예측하는 방법이 연구되고 있다. 본 논문에서는 선형 방정식을 이용하여 생산 단수, 생산 면적, 기후 요소를 예측하였으며, 기후 요소의 가중치 합을 이용하여 보정된 생산 단수와 생산 면적을 곱하여 생산량을 계산하였다. 실험에서 예측한 생산량은 실제 생산량과 비교하여 약 90% 이상의 예측율을 보였다.

• 대한전기학회논문지:전력기술부문A
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• 제52권2호
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• pp.79-89
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• 2003

A research about finding a new electricity load model that is sensitive to the price of electricity is conducted. This new model i5 polynomial type price sensitive electricity consumption model, while former electricity consumption models have exponential terms or statistic terms. The pattern of electricity consumption of each electricity using devices were identified first, then the proportion of the devices at buses or nodes are investigated, finally weighted sum of electricity consumption and the proportion makes the load model or consumption model of electricity at one bus or node. This new model is easy to use in the simulations or calculations of the electricity consumption, because the arithmetic of functions with polynomial terms are easy compared to the functions with transcendental terms.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 1999년도 춘계 학술대회논문집
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• pp.199-204
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• 1999

Three dimensional numerical analysis for the turbulent reactive flow and radiative heat transfer in the walking beam type of a reheat furnace in POSCO has been carried out by the industrial code FLUENT. Computations an based on the conservation equations of mass, momentum, energy and species with the $k-{\varepsilon}$ turbulence model and mixture fraction/PDF(Probability Density Function) approach for the combustion rate. Radiative heat transfer is computed by the discrete ordinates radiation model in combination with the weighted-sum-of-gray-gas model for the absorption coefficient of gas medium. The predicted temperture distribution in the reheat furnace and energy flow fractions are in reasonable agreement with the measurement data.

• 한국철도학회논문집
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• 제14권6호
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• pp.569-574
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• 2011

정된 예산으로 철도선로시설을 개선하고자 할 때 사용할 수 있는 효과적인 예산배분 방법 중 하나는 가장 노후도가 심각한 선로구간부터 우선적으로 예산을 투입하는 것이다. 본 논문에서는 예산배분에 사용할 수 있는 선로구간 노후도 평가방법을 제시한다. 선로구간의 노후도는 궤도, 분기기, 노반, 교량, 터널 등 요소 시설물의 노후도로 결정되며 궤도의 선형 또한 선로구간 노후도에 영향을 준다. 본 논문에서 제시하는 노후도 평가 방법은 각 요소의 노후도 점수에 AHP로 구한 요소 가중치를 반영하여 선로구간 노후도 점수를 구하는 것이다.

• ETRI Journal
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• 제36권4호
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• pp.617-624
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• 2014

Through-silicon via (TSV) technology provides much of the benefits seen in advanced packaging, such as three-dimensional integrated circuits and 3D packaging, with shorter interconnection paths for homo- and heterogeneous device integration. In TSV, a destructive cross-sectional analysis of an image from a scanning electron microscope is the most frequently used method for quality control purposes. We propose a quantitative evaluation method for TSV etch profiles whereby we consider sidewall angle, curvature profile, undercut, and scallop. A weighted sum of the four evaluated parameters, nominally total score (TS), is suggested for the numerical evaluation of an individual TSV profile. Uniformity, defined by the ratio of the standard deviation and average of the parameters that comprise TS, is suggested for the evaluation of wafer-to-wafer variation in volume manufacturing.

• 한국시뮬레이션학회논문지
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• 제6권1호
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• pp.71-84
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• 1997

For many optimization problems where some of the system components are stochastic, the objective functions cannot be represented analytically. Therefore, modeling by computer simulation is one of the most effective means of studying such complex systems. Many, if not most, simulation optimization problems have multiple aspects. Historically, multiple aspects have been combined ad hoc to form a scalar objective function, usually through a linear combination (weighted sum) of the multiple attributes, or by turning objectives into constraints. The genetic algorithm (GA), however, is readily modified to deal with multiple aspects. In this paper we propose a MAGA (Multiple Aspects-based Genetic Algorithm) as an algorithm for finding the Pareto optimal set. We demonstrate its ability to find and maintain a diverse "Pareto optimal population" on two problems.

• 태양에너지
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• 제19권1호
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• pp.67-75
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• 1999

The effect of radiation heat transfer was investigated under various operating conditions in a circular tube with circumferential fins and circular disks. Using a finite volume technique(FVM) for steady laminar flow, the governing equations were derived in order to simulate the flow and temperature fields. In addition, the P-1 approximation and the Weighted Sum of Gray Gas Model(WSGGM) were used for the radiation transport equation(RTE). From the results, radiation heat transfer was significant compared to convection heat transfer. These results will be applied to the design of the heat exchanger for a condensing bolier, which were developed for domestic heating.

• Journal of Communications and Networks
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• 제18권4호
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• pp.629-638
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• 2016

In this paper, we investigate an energy-efficient resource allocation problem in a two-way relay (TWR) network consisting of multiple user pairs and an amplify-and-forward (AF) relay. As the users and relay have individual energy efficiencies (EE), we formulate a multi-objective optimization problem (MOOP). A single-objective optimization problem (SOOP) of the MOOP is introduced using a weighted-sum method, which achieves a single Pareto optimal point of the MOOP. To derive the algorithm for the SOOP, we propose a more tractable equivalent problem using the Karush-Kuhn-Tucker conditions of the SOOP, which guarantees convergence at the local optimal points. The proposed equivalent problem can be efficiently solved by the proposed iterative algorithm. Numerical results demonstrate the effectiveness of the proposed algorithm in achieving the optimal EE in multi-user AF TWR networks.

• 대한산업공학회지
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• 제35권4호
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• pp.218-225
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• 2009

This paper considers a parallel-machine scheduling problem with job release times and sequence-dependent setup times. The objective of this problem is to determine the allocation policy of jobs and the scheduling policy of machines so as to minimize the weighted sum of setup times, delay times, and tardy times. A mathematical model for optimal solution is derived and a meta heuristic algorithm based on the improved ant colony system is proposed in this paper. The performance of the meta heuristic algorithm is evaluated through compare with optimal solutions using randomly generated several examples.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 B
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• pp.936-938
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• 1996

The $H_{\infty}$ robust controller is designed for on-line adaptive control application by using polynomial approach. The $H_{\infty}$ robust controllers for adaptive system were designed first by Grimble. But they have a problem that two minimum costs can exist and did not minimize the conventional $H_{\infty}$ cost function which is the $H_{\infty}$ sum of weighted sensitivity and complementary sensitivity terms. In this paper, the two minimum costs problem can be avoided and the conventional $H_{\infty}$ cost function is minimized by employing the Youla parameterization and polynomial approach at the same time. In addition pole placement is possible without any relation with weighting function.