• 한국기계가공학회지
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• 제7권3호
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• pp.87-95
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• 2008

The purpose of this study is to provide a decision support to select an appropriate rapid prototyping(RP) machine that suits the application of a part. Selection factors include concept model, form/fit/functional model, pattern model for molding, material property, build time and part cost that greatly affect the performance of RP machines. However, the selection of a RP is not an easy decision because they are uncertain and vague. For this reason, the aim of this research is to propose hybrid multiple attribute decision making approaches to effectively evaluate RP machines. In addition, because subjective considerations are relevant to selection decision, a fuzzy logic approach is adopted. The proposed selection procedure consists of several steps. First, we identify RP machines that the users consider. After constructing the evaluation criteria, we calculate the weights of the criteria by applying the fuzzy Analytic Hierarchy Process(AHP) method. Finally, we construct the fuzzy Technique of Order Preference by Similarity to Ideal Solution(TOPSIS) method to achieve the ranking order of all machines providing the decision information for the selection of RP machines.

• 대한산업공학회지
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• 제20권4호
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• pp.5-21
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• 1994

We have described the optimal process route selection model for the PCB(printed circuit board) auto-insertion line. This PCB assembly line is known as a FFL(flexible flow line) which produces a range of products keeping the flow shop properties. Under FFL environments, we have emphasized the balancing of work-loads in order to maximize total productivity of PCB auto-insertion line. So we have developed a heuristic algorithm based on a work-order selection rule and min-max concept for the job route selection model.

• 한국정보시스템학회지:정보시스템연구
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• 제13권2호
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• pp.49-64
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• 2004

Recently, SCM(Supply Chain Management) embraces the dynamic environmental changes of the participatory bodies in supply chain. Under this dynamic SCM environment, the selection of supplier and outsourcing company is very important. In their selection, the productivity and expertise of suppliers and outsourcing companies are, of course, to be considered as important factors, but whether or nottheycanmeettheduedateisacritical factor. In particular, this is true because an order-based manufacture ought to have CTP(Capable To Promise). For this purpose, by capitalizing onthevirtualmanufactureundertheSCM, this paper has tried to suggest a new agent system for the selection of supplier and outsourcing company. While performing virtual manufacture based on the integration scheduling, this system acquires the production environment and scheduling information of both suppliers and outsourcing companies on a real-timebasis,thusmakingintegrationschedulingpossible. Also, in order to provetheviabilityofthisstudy,thispaper has selected a specific domain and applied it.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제2권1호
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• pp.41-60
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• 1998

This paper derives a consistent and bias corrected extension of Akaike's Information Criterion (AIC), $AIC_{bc}$, based on Kullback-Leibler information. This criterion has terms that penalize the overparametrization more strongly for small and large samples than that of AIC. The overfitting problem of the asymptotically efficient model selection criteria for small and large samples will be overcome. The $AIC_{bc}$ also provides a consistent model order selection. Thus, it is widely applicable to data with small and/or large sample sizes, and to cases where the number of free parameters is a relatively large fraction of the sample size. Relationships with other model selection criteria such as $AIC_c$ of Hurvich, CAICF of Bozdogan and etc. are discussed. Empirical performances of the $AIC_{bc}$ are studied and discussed in better model order choices of a linear regression model using a Monte Carlo experiment.

• Journal of Information Processing Systems
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• 제19권4호
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• pp.407-416
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• 2023

In order to effectively relieve the traffic pressure of the city, ensure the smooth flow of freight and promote the development of the logistics industry, the selection of appropriate port logistics location is the basis of giving full play to the port logistics function. In order to better realize the selection of port logistics, this paper adopts the entropy weight method to set up a multi-dimensional evaluation index, and constructs the evaluation model of port logistics location. Then through the actual case, from the environmental dimension and economic competition dimension to make choices and analysis. The results show that port d has the largest logistics competitiveness and the highest relative proximity among the three indicators of hinterland city economic activity, hinterland economic structure, and port operation capacity of different port logistics locations, which has absolute advantages. It is hoped that the research results can provide a reference for the multi-dimensional selection of port logistics site selections.

• 한국정보기술학회 영문논문지
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• 제10권1호
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• pp.1-14
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• 2020

Antenna selection is a method to enhance the performance of spatial multiplexing multiple-input multiple-output (MIMO) systems, which can achieve the diversity order of the full MIMO systems. Although various selection criteria have been studied in the literature, they should be adjusted to the detection operation implemented at the receiver. In this paper, antenna selection methods that optimize the post-processing signal-to-noise ratio (SNR) and eigenvalue are considered for the lattice reduction (LR)-based receiver. To develop a complexity-efficient antenna selection algorithm, the incremental selection strategy is adopted. Moreover, for improvement of performance, an additional iterative selection method is presented in combination with an incremental strategy.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제4권5호
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• pp.819-835
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• 2010

In this paper, two selection relaying schemes are proposed and compared with each other in terms of packet error rate (PER) and diversity order. Moreover, the comparison is performed over two different fading environments including fast and slow fading environments in which the diversity order is considered as the important factor to reach the decision which scheme is suitable for each fading environment. Numerical results validate the analytical results and indicate significant differences on the PER performance of two schemes over two fading environments.

• Macromolecular Research
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• 제16권1호
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• pp.51-56
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• 2008

Spherical micelles of poly(styrene-b-isoprene) (SI) diblock copolymers in selective solvents have been reported to pack onto either face-centered cubic (fcc) or body-centered cubic (bcc) lattices. The selection rule for fcc and bcc lattices has been understood in terms of the intermicellar potentials, and they have been quantified using the ratio of the corona layer thickness to the core radius, $L/R_c$, as suggested by McConnell and Gast. In order to test the validity of the McConnell-Gast criterion, this study compared the $L/R_c$ values from various solutions i.e. nine SI copolymers in several different selective solvents. The McConnell-Gast criterion was not found to be a determining factor, even though it could explain the fcc/bcc selection qualitatively. From the phase diagrams, the transition between fcc and bcc phases was also considered as a function of concentration and temperature, and their physical mechanisms are discussed based on the recent mean-field calculation reported by Grason.

• Industrial Engineering and Management Systems
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• 제11권2호
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• pp.155-164
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• 2012

As the global market becomes more competitive, manufacturing industries face relentless pressure caused by a growing tendency of greater varieties of products, shorter manufacturing cycles and more sophisticated customer requirements. Efficient and effective supplier selection and order allocation decisions are, therefore, important decisions for a manufacturer to ensure stable material flows in a highly competitive supply chain, in particular, when customers are willing to accept products with less desirable product attributes (e.g., color, delivery date) for economic reasons. This paper attempts to solve optimally the challenging problem of supplier selection and order allocation, taking into consideration the customer flexibility for a manufacturer producing multi-products to satisfy the customers' demands in a multi period planning horizon. A new mixed integer programming model is developed to describe the behavior of the supply chain. The objective is to maximize the manufacturer's total profit subject to various operating constraints of the supply chain. Due to the complexity and non-deterministic polynomial-time (NP)-hard nature of the problem, an improved genetic approach is proposed to solve the problem optimally. This approach differs from a canonical genetic algorithm in three aspects: a new selection method to reduce the chance of premature convergence and two problem-specific repair heuristics to guarantee feasibility of the solutions. The results of applying the proposed approach to solve a set of randomly generated test problems clearly demonstrate its excellent performance. When compared with applying the canonical genetic algorithm to locate optimal solutions, the average improvement in the solution quality amounts to as high as ten percent.

• 디지털융복합연구
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• 제13권11호
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• pp.217-230
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• 2015

본 연구는 의료이용 동기(경증, 중증, 만성질환관리, 미용)에 따른 의료기관 선택기준의 차이를 알아보기 위해 시행되었다. 의료이용 동기에 따른 병원선택요인의 중요도는 감기와 같은 경증질환의 경우 진료능력, 친절, 신속, 접근성 순이었으며 암과 같은 중증질환의 경우와 미용의 경우는 진료능력, 시설, 평판, 진료비 순이었고 합병증 없는 고혈압관리와 같은 만성질환 관리의 경우는 진료능력, 시설, 친절, 진료비 순이었다. 의료이용 동기와 관계없이 진료능력은 의료기관 선택에 가장 중요한 요인이었으며 중증질환의 경우 접근성을 제외한 모든 요인에 대한 중요도가 높았다. 결론적으로 의료이용자들은 의료이용 동기, 질병의 심각성과 위급성 등을 복합적으로 고려하여 의료기관을 선택하며 같은 경우라도 인구학적 특성 및 정보탐색행태에 따라서 달라진다는 점을 알 수 있었다. 이에 의료기관의 경쟁우의를 확보하기 위해 수동적인 태도, 타 의료기관의 무조건적인 모방이 아니라 의료기관 선택요인에 대한 이해를 바탕으로 타 의료기관과 차별화하는 전략을 세워야 할 것이다.