• 한국정밀공학회지
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• 제21권9호
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• pp.149-157
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• 2004

This paper presents a new method for hi-objective optimization. Ordinary weighted sum method is easy to implement, but it has two significant drawbacks: (1) the solution distribution by the weighted sum method is not uniform, and (2) the method cannot determine any solutions that reside in non-convex regions of a Pareto front. The proposed adaptive weighted sum method does not solve a multiobjective optimization in a predetermined way, but it focuses on the regions that need more refinement by imposing additional inequality constraints. It is demonstrated that the adaptive weighted sum method produces uniformly distributed solutions and finds solutions on non-convex regions. Two numerical examples and a simple structural problem are presented to verify the performance of the proposed method.

• 대한수학회보
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• 제60권1호
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• pp.123-135
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• 2023

The goal of this article is to introduce the concept of pseudo-weighted Browder spectrum when the underlying Hilbert space is not necessarily separable. To attain this goal, the notion of α-pseudo-Browder operator has been introduced. The properties and the relation of the weighted spectrum, pseudo-weighted spectrum, weighted Browder spectrum, and pseudo-weighted Browder spectrum have been investigated by extending analogous properties of their corresponding essential pseudo-spectrum and essential pseudo-weighted spectrum. The weighted spectrum, pseudo-weighted spectrum, weighted Browder, and pseudo-weighted Browder spectrum of the sum of two bounded linear operators have been characterized in the case when the Hilbert space (not necessarily separable) is a direct sum of its closed invariant subspaces. This exploration ends with a characterization of the pseudo-weighted Browder spectrum of the sum of two bounded linear operators defined over the arbitrary Hilbert spaces under certain conditions.

• 한국통신학회논문지
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• 제38A권7호
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• pp.560-570
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• 2013

본 논문에서는 셀 간 간섭과 셀 내 사용자 간 간섭이 공존하는 two-cell 다중 안테나 하향링크 간섭 채널에서 송수신기 설계 방법을 제안한다. 우선 셀 간 간섭과 셀 내 사용자 간 간섭을 다차원 subspace에 정렬하는 zero-forcing 간섭 정렬 방법을 일반화한다. 그리고 일반화한 zero-forcing 간섭 정렬 방법에서 구한 송수신기를 "regularizing" 하는 minimum weighted-mean-square-error 기반 regularized ZF-IA 방법을 제안한다. 기존 weighted-sum-rate-maximizing 송수신기 설계 방법에 비해 제안하는 방법은 weight 를 구하는 반복 연산 과정이 필요하지 않다. 그 결과 제안하는 방법은 비록 sum-rate 최대화하도록 설계되진 않았지만, 기존의 weighted-sum-rate maximizing 방법 보다 계산 복잡도 면에서 효율적이고 더 빠른 수렴 속도를 얻을 수 있다. 다양한 분석과 실험을 통해 제안하는 regularized ZF-IA 방법의 우수성을 확인하였다. 구체적으로 반복 연산 수가 작은 경우, 제안하는 regularized ZF-IA 방법의 sum-rate 성능이 기존의 weighted-sum-rate maximizing 방법보다 SNR = 20 [dB] 에서 약 49.8 % 이상 나음을 확인할 수 있다. 더불어 채널 정보에 오차가 있는 경우 상당한 robustness를 제공하는 robust 송수신기 설계 방법도 제시한다.

• Genomics & Informatics
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• 제14권4호
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• pp.173-180
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• 2016

The meta-analysis has become a widely used tool for many applications in bioinformatics, including genome-wide association studies. A commonly used approach for meta-analysis is the fixed effects model approach, for which there are two popular methods: the inverse variance-weighted average method and weighted sum of z-scores method. Although previous studies have shown that the two methods perform similarly, their characteristics and their relationship have not been thoroughly investigated. In this paper, we investigate the optimal characteristics of the two methods and show the connection between the two methods. We demonstrate that the each method is optimized for a unique goal, which gives us insight into the optimal weights for the weighted sum of z-scores method. We examine the connection between the two methods both analytically and empirically and show that their resulting statistics become equivalent under certain assumptions. Finally, we apply both methods to the Wellcome Trust Case Control Consortium data and demonstrate that the two methods can give distinct results in certain study designs.

• 품질경영학회지
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• 제26권3호
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• pp.100-107
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• 1998

To evaluate the total quality activities is the most fundamental and critical process as one of the PDCA cycle. The quality award criteria such as Malcolm Baldrige National Quality Award and Deming Award can be a, pp.ied to the guideline for evaluating quality activities. We can identify several important factors for TQM by referring quality award criteria, but they don't suggest how efficiently implement TQM. In this paper, two methodologies are a, pp.ied to evaluate the TQM activities comparatively. One of them is the traditional scoring system (TSS) by analytic hierarchy process (AHP). TSS is the system which evaluates the performance of TQM by the weighted sum of critical success factors. Several quality award system are typical examples of TSS. The other is the efficiency measuring system (EMS) by data envelop analysis (DEA). DEA outperformed other alternative methods to measure the efficiency and it can be a, pp.ied to evaluate the TQM activities. The evaluation system by DEA can be named as EMS. The objective of this paper is to suggest a model called TAE (Total quality management Activities Evaluation), for evaluating TQM activities. In this model TQM organizations are classified into four types by considering TSS and EMS. Those types are high weighted sum and high efficiency type, high weighted sum and low efficiency type, low weighted sum and high efficiency type, and low weighted sum and low efficiency type. Therefore TQM organizations must not only make efforts to get the higher scores in terms of TSS, but also take necessary steps to enhance their efficiencies.

• Smart Structures and Systems
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• 제22권4호
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• pp.469-479
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• 2018

The present research study utilizes a multi-objective optimization method for Pareto optimization of an eight-degree of freedom full vehicle vibration model, adopting a non-dominated sorting genetic algorithm II (NSGA-II). In this research, a full set of ride comfort as well as ride safety parameters are considered as objective functions. These objective functions are divided in to two groups (ride comfort group and ride safety group) where the ones in one group are in conflict with those in the other. Also, in this research, a special optimizing technique and combinational method consisting of weighted sum method and Pareto optimization are applied to transform Pareto double-objective optimization to Pareto full-objective optimization which can simultaneously minimize all objectives. Using this technique, the full set of ride parameters of three dimensional vehicle model are minimizing simultaneously. In derived Pareto front, unique trade-off design points can selected which are non-dominated solutions of optimizing the weighted sum comfort parameters versus weighted sum safety parameters. The comparison of the obtained results with those reported in the literature, demonstrates the distinction and comprehensiveness of the results arrived in the present study.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.821-822
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• 2008

This paper presents a new demosaicking method based on weighted sum in the wavelet domain. In our method, the missing wavelet coefficients in lowest frequency subband are obtained by weighted sum. Since detail coefficients have large values at the edge region, these values are used as weighting factors. Detail coefficients are replaced by the coefficients in the corresponding subbands. Experimental results show that the proposed method generates good performance.

• 대한수학회보
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• 제58권5호
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• pp.1261-1278
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• 2021

Recently, a new kind of multiple zeta value of level two T(k) (which is called multiple T-value) was introduced and studied by Kaneko and Tsumura. In this paper, we define a kind of alternating version of multiple T-values, and study several duality formulas of weighted sum formulas about alternating multiple T-values by using the methods of iterated integral representations and series representations. Some special values of alternating multiple T-values can also be obtained.

• 전자공학회논문지B
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• 제30B권10호
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• pp.50-58
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• 1993

The problem of trajectory planning in two redundant robot systems is considered. The trajectory of each robot for the cooperative task is generated so that the robots assume their optimal configurations while following a given desired task. The cooperative task compatibility in and the weighted sum of manipulabilities are proposed and investigated as quality measures. The cooperative task compatibility includes the velocity and force transmission charateristics to the task requirements and so it measures the compatibilities of robot postures with respect to a given task. The weighted sum of manipuabilities of robot postures with respect to a given task. The weighted sum of manipulabilities is also considered as a quality measure since it is helpful to avoid singularities. The usefulness of the cooperative task compatibility and the weighted sum of manipulabilities are shown by computer simulation studies.

• 한국산학기술학회논문지
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• 제16권1호
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• pp.97-105
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• 2015

다중반응표면 최적화는 다수의 반응변수(품질특성치)를 최적화하는 입력변수의 조건을 찾는 것을 목적으로 한다. 다중반응표면 최적화를 위해 제안된 가중평균제곱오차(Weighted Mean Squared Error, WMSE) 최소화법은 평균제곱오차의 구성요소인 제곱편차와 분산에 서로 다른 가중치를 부여하는 방법이다. 지금까지 WMSE 최소화법과 관련하여, 개별 반응변수의 WMSE를 구성한 후 이들의 가중합을 최소화하는 가중합 기반 WMSE 최소화법이 제안되었다. 그러나 가중합 기반법은 목적함수 공간에서 볼록하지 않은 구간이 있고 이 구간에서 가장 선호되는 해가 존재할 경우 이 해를 찾아내지 못한다는 한계를 지니고 있다. 본 논문에서는 기존의 가중합 기반법의 한계점을 극복하기 위하여 Tchebycheff Metric 기반 WMSE 최소화법을 제안하고자 한다.