• International Journal of Precision Engineering and Manufacturing
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• 제7권3호
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• pp.39-46
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• 2006

This paper presents an elastic deformation model of a spindle unit (S/U), which takes into account the non-linear properties of high-speed ball bearings (particularly the effect of high rotational speed). For this, a software for the estimation of the S/U elastic deformation properties was developed and intended for use by S/U designers. A computer aided analysis of the model using the developed software was carried out and experiments showed the significant effect of rotational speed, cutting load and bearing axial preload, and showed some new phenomena, from which the criteria for the choice of bearing axial preload is given.

• 대한치과의사협회지
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• 제58권7호
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• pp.413-434
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• 2020

Recently, there are much improvement in optical and mechanical properties of dental ceramic materials coupled with improved fabrication techniques, which have caused a considerable shift in the preference of the dentists to ceramic restorations. Because the chemical composition and microstructure of all-ceramic materials are different by the type, correct choice of cement type and surface treatment procedure, and cementation strategy is essential for the success of ceramic restorations with adequate retention and decreased incidence of complications. This manuscript reviews on the most often prescribed and some newly developed ceramic materials, and the selection criteria and usage guidelines of cement materials that are used in conjunction with various ceramic materials. This manuscript emphasizes that continuous updating the information of newly developed ceramic and cement materials and application techniques by the dentists and dental staffs are demanding in response to the constantly improving ceramic and cement materials and corresponding application protocol changes.

• Asia pacific journal of information systems
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• 제5권1호
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• pp.52-85
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• 1995

This paper develops a new approach to dealing with qualitative reasoning processes involved in managerial decisions, drawing upon choice strategies that have been developed within the general framework of multi-criteria decision making. Issues such as choices under uncertainty and preference formulation are addressed. An MCDM DSS intended to assist in high-level management decisions must focus on helping the decision maker to properly define the problem by providing a structure to it and to dynamically evaluate the alternative courses of action. A conceptual architecture is developed and presented to propose a general model for designing decision support systems specifically designed to assist in MCDM in a managerial context. A commercial loan approval judgment case is described to illustrate the real-world situation where decisions are made under fuzziness and usually require a high degree of intuition and subjective judgment. Development of a prototype system intended to partially represent application of the architecture is described.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2002년도 춘계공동학술대회
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• pp.1006-1013
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• 2002

The multiplicity of operating systems brings about a choice problem to the end-user and a multi-fold intensity to the competing developer. This study intends to provide guidelines solving the problems for both the end-user and the developers of operating systems. For the purpose, we adopt an appropriate evaluation model in terms of user-perceived quality through the applicable criteria and an evaluation method. Briefly, reliability and portability are key factors to contribute to the perceived duality. The empirical study also illustrates a comparative analysis on the dominant products. Microsoft Windows and Linux, in Korea.

• Journal of Information Processing Systems
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• 제13권4호
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• pp.941-950
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• 2017

The round robin algorithm is regarded as one of the most efficient and effective CPU scheduling techniques in computing. It centres on the processing time required for a CPU to execute available jobs. Although there are other CPU scheduling algorithms based on processing time which use different criteria, the round robin algorithm has gained much popularity due to its optimal time-shared environment. The effectiveness of this algorithm depends strongly on the choice of time quantum. This paper presents a new effective round robin CPU scheduling algorithm. The effectiveness here lies in the fact that the proposed algorithm depends on a dynamically allocated time quantum in each round. Its performance is compared with both traditional and enhanced round robin algorithms, and the findings demonstrate an improved performance in terms of average waiting time, average turnaround time and context switching.

• 품질경영학회지
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• 제27권1호
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• pp.195-210
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• 1999

The multiplicity of software packages brings about a choice problem to the end-user and a multi-fold intensity to the competing developer. This study intends to provide guidelines solving the problems for both the end-user and the developer of packages for automatic statistical analyses. For the purpose, we adopt an appropriate evaluation model in terms of user-perceived quality through the applicable criteria and an evaluation method. The result of empirical study is described, which shows that the weight of each criterion is dynamic along usage levels. Briefly, functionality, usability, and reliability are key factors to contribute to the perceived quality. The empirical study also illustrates a comparative analysis on the dominant products, SAS and SPSS, in Korea.

• 한국국방경영분석학회지
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• 제27권2호
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• pp.37-55
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• 2001

The main purpose of this study is to review the current system and to develop a decision support system for evaluating the priorities among those possible alternatives in the army facility enterprise. This paper also provides an information system which can be effectively applied to various criteria and stages in decision making process such as Planning and Programming phases in PPBEES. The model base of decision support systems uses the concepts of the analytic hierarchy process along with the supplementary techniques such as TOPSIS and 0-1 integer programming. Both AHP and TOPSIS are used scoring approaches in the Planning phase and IP is induced at the Programming phase to give GO/NO-GO solution for each project. We use Expert Choice, Excel and LINDO s/w's to implement a prototyped model. The proposed methodology in this paper enables the decision makers to evaluate the priority based on quantitative and qualitative data in a systematic way.

• International Journal of Computer Science & Network Security
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• 제21권12호
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• pp.257-263
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• 2021

Though many have studied choosing one of the alternative ways to reach a destination, the factors such as average road speed, distance, and number of traffic signals, traffic congestion, safety, and services still presents an indisputable challenge. This paper proposes two approaches: Appropriate membership function and ambiguous rule-based approach. It aims to tackle the route choice problem faced by almost all drivers in any city. It indirectly helps in tackling the problem of traffic congestion. The proposed approach considers the preference of each driver which is determined in a flexible way like a human and stored in the driver profile. These preferences relate to the criteria for evaluating each candidate route, considering the average speed, distance, safety, and services available. An illustrative case study demonstrates the added value of the proposed approach compared to some other approaches.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.606-614
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• 2005

This paper deals with new realizations of research, scientific development, managerial and economic optimizations for prefabricated building systems. In the literature, all scientific fields are worked out based on the efficiencies, costs, benefits, choice of execution design, technical demands, aesthetical point of view, as well as the total economics. In the present example of a school-building for communities in the third world, the following criteria have been regarded: The optimal superstructure of prefabricated concrete building systems; the particularity of countries of the Third World (e.g. the climate, the political and the economic conditions); the time for construction and necessary innovative developments for an economically optimized superstructure. Added to this are alternative construction-methods and costs for a simple but variable system which can be adapted to changing functions, where variability should be the main point. For example, a school building that is to be adapted by varying number of rooms to cater for the growing number of pupils.

• Archives of Plastic Surgery
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• 제34권5호
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• pp.569-573
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• 2007

Purpose: The selection of the recipient vessels in breast reconstruction has a great influence on the surgical result and the shape of the reconstructed breast. We would like to introduce the criteria for the selection of recipient vessels in delayed reconstruction of the breast. Methods: We studied 56 patients with delayed breast reconstruction using free TRAM flaps from April 1994 to December 2006. The thoracodorsal and the ipsilateral internal mammary vessels were used as recipients in 25 patients each, the opposite internal mammary vessels in 3 patients, the thoracoacromial vessels in 2 patients, and the transverse cervical artery with the cephalic vein in 1 patient. The survival rate of the flaps, the vessel diameter, the length of the pedicles, and the convenience of vessel dissection were studied. Results: The diameter of the recipient vessel did not influence the anastomosis. The operation time, the survival rate of flap, the postoperative complications showed no significant difference according to the recipient vessel. Dissection of the thoracodorsal vessels was tedious due to scar formation from the prior operation. Dissection of the internal mammary vessels proved to be relatively easy, and the required length of the pedicle was shorter than any other site, but the need for removal of rib cartilage makes this procedure inconvenient. Conclusion: The first choice of the recipient vessel in immediate breast reconstruction is the thoracodorsal vessels, but in cases of delayed reconstruction the internal mammary vessels are favored as the first choice, because the thoracodorsal vessels have a high unusability rate. If the ipsilateral internal mammary vessels prove to be useless, the contralateral vessels can be used. The thoracoacromial vessels are useful, when the mastectomy scar is located in the upper portion. The transverse cervical artery and the cephalic vein can serve as the last resort, if all other vessels are unreliable.