• Journal of Korean Society of Industrial and Systems Engineering
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• v.25 no.5
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• pp.31-38
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• 2002

In this paper, we model a two-server queueing system with priority, to which we put a restriction on the number of servers for each customer class. customers are divided into two different classes. Class 1 customers have non-preemptive priority over class 2 customers. They are served by both servers when available but class 2 customers are served only by a designated server. We use a method of generating function depending on the state of servers. We find the generating function of the number of customers in queue, server utilization, mean queue length and mean waiting time for each class of customers.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.36 no.1
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• pp.70-77
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• 2013

The theory of two-dimensional quality, in particular, the Kano model that is developed by the analogy with the M-H theory, has been applied in various industry fields for more than three decades. Importance-Performance Analysis (IPA) assumes that the degree of physical fulfilment of quality attributes and the satisfaction of that attribute is linear, and therefore, it is applicable to the traditional one-dimensional attribute, not other quality types defined in the Kano's model such as attractive or must-be attribute. To solve this problem, the current study suggests a new importance-satisfaction analysis using a modified IPA in accordance with the three quality types and a diagonal method introduced by Slack (1999) to determine improvement priority. For this, I investigated 19 smartphone's quality attributes and conducted a survey of 334 university students for the results of Kano's model, which adopted from Song and Park (2012)'s study, and the importance/satisfaction of the quality attributes and the results of the priority for improvement of the 19 quality attributes. The results show that the proposed I-S priority model is better than the conventional IPA based on the comparison results of determination coefficient from the regression analysis of the two models.

• The KIPS Transactions:PartA
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• v.13A no.5 s.102
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• pp.405-412
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• 2006

Real-time operating systems have been used in various computing environments, where a job must be completed in its deadline, with various conditions, such as effective scheduling policies, the minimum of an interrupt delay, and the solutions of priority inversion problems, that should be perfectly satisfied to design and develop optimal real-time operating systems. Up to now, in order to solve priority inversion problems among several those conditions. There have been two representative protocols: basic priority inheritance protocol and priority ceiling emulation protocol. However, these protocols cannot solve complicated priority inversion problems. In this paper, we design a protocol, called recursive priority inheritance (RPI), protocol that effectively solves the complicated priority inversion problems. Our proposed protocol is also implemented in the Linux kernel and is compared with other existing protocols in the aspect of qualitative analysis.

• Journal of the military operations research society of Korea
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• v.30 no.2
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• pp.122-132
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• 2004

The aim of this paper is to show the process of R&D Project-Priority Ordering in the Defense Technology field. We propose specific methods (Delphi, Analytic Hierarchy Process (AHP), Scoring) to order the R&D Project-Priority. In general, to decide the priority of R&D projects most of researches depend on questionnaires which are surveyed by experts. However, it is criticized that this process cannot reflect the limitation of experience and knowledge of experts. In this process, we separate evaluators in two parts: the first is strategic experts, the second is technical experts. Evaluators can choose and evaluate the alternatives which they are familiar with, so we can obtain reliable results. Finally, based on our process of the R&D Project-Priority Ordering we formulate policy implications for managing the defense technology.

• Journal of the Korean Chemical Society
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• v.38 no.6
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• pp.418-426
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• 1994

This study was aimed at the detection of 40 semi-volatile organic base/neutral compounds from soil among 129 priority pollutants listed by EPA. Two extraction procedures, sonication extraction and Soxhlet extraction, were studied as a extraction and concentration method for priority pollutants in soil. Extracts were analyted by GC/MS-SIM(selected ion monitoring). The analytical methods were tested by standard compounds spiked into blank soil. Accuracy and precision of the methods were measured by calculation of mean recovery and mean relative standard deviation. And the method detection limits were estimated.

• Journal of the Korean Chemical Society
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• v.38 no.3
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• pp.246-253
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• 1994

The simultaneous analysis of 11 semi-volatile organic acid compound which are listed as priority pollutants by EPA, were performed by GC/MS-SIM(selected ion monitoring). Two extraction procedures, sonication extraction and Soxhlet extraction, were studied as an extraction and concentration method for priority pollutants in soil. Accurecy and precision of the methods were measured by the calculation of mean recovery, mean relative standard deviation, and method detection limit. Finally, limitations and prospects were discussed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.2
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• pp.140-149
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• 2000

A comparative analysis was peformed on the operation cost at partial loads between ice storage systems with the two conventional control strategies, i.e., storage priority and chiller priority. The storage priority control is shown to be more economic for small cooling loads, while the chiller priority control is superior when the cooling load is as large as the design value. Based on this finding, a new control strategy is devised for an ice-storage system to minimize the operation cost at any cooling load. The new control strategy is found to be comparable to the chiller priority for large cooling loads, while it is more economic for small loads compared to the conventional control strategies. The practicality of the new control strategy is also confirmed through a performance test applying the new control strategy to an existing ice-storage system.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.48
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• pp.291-297
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• 1998

This paper considers the determination of the priority of investment on R&D planning on nuclear power technology using AHP. Due to the complexity of problem, the hierarchy was divided into two parts; main hierarchy and sub-hierarchies. The result shows that the priority of technology options of evolutionary reactor and safety evaluation was higher than that of others.

• The Korean Journal of Franchise Management
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• v.11 no.4
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• pp.45-57
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• 2020

Purpose: The purpose of this study is to determine the importance and priority arising from the relationship between MRO-office supplies franchisor ("franchisor") and franchisees through an in-depth investigation. In particular, with respect to the MRO-Office franchise industry, we would like to make meaningful contributions in the decision-making process by comparing and contrasting factors that affect the importance and priority of communication, conflict, support and satisfaction through AHP analysis. Research design, data, and methodology: After completion of AHP analysis, the study will also identify factors in order of priority and factors of importance between the franchisor and franchisees. Another purpose of this study is to evaluate and propose business relationship strategies between the franchisor and franchisees. Through AHP analysis, this study will facilitate the relationship between the franchisor and franchise, and determine the factors of importance and factors in order of priority. Result: This study evaluates the differences and priorities of the two groups arising from the relationship between the franchisor and the franchisees through AHP analysis after separately analyzing the franchisor. In this study, the franchisees find that communication is the most important factor, then support as the second most important factor between the two groups. In contrast, the franchisor finds that support is the most important factor followed by communication between the two groups. Conclusions: This analysis demonstrates the discrepancy in evaluating important factors from the perspectives of the franchisor and the franchisees. The largest discrepancy between the franchisor and franchisees comes from an information system related to communication factors. This effectively means that the franchisor has an understanding of this inadequate information system on the part of franchisees but this understanding is not deemed an important factor. The franchisees recognize and focus on the need to obtain feedback from the franchisor regarding management improvement as the most important factor rather than the ability of the franchisor to guide them through the franchisees' operations. To this end, the franchisor should be more flexible in dealing with the problem of improving the work required by the franchisees. For this study, a survey was conducted on employees of MRO-office supplies franchisor, franchisees, and employees and completed based on AHP analysis.

• The Transactions of the Korea Information Processing Society
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• v.7 no.11S
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• pp.3684-3693
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• 2000

In this paper, performance of a nonblocking high speed packet switch with switching capacity m which adopts a dynamic priority control function (DPCF) of a threshold- based Bernoulli priority jump (TBPJ) scheme is considered. Each input queue has two separate buffers with different sizes for two classes of traffics, delay-sensitive and loss-sensitive traffics, and adopts a TBPJ scheme that is a general state-dependent Bernoulli scheduling scheme. Under the TBP] scheme, a head packet of the delay-sensitive traffic buffer goes into the loss -sensitive traffic buffer with Hernoulli probability p according to systems states that represent the buffer thresholds and the number of packets waiting for scheduling. Performance analysis shows that TBPJ scheme obtains large performance build-up for the delay-sensitive traffic without performance degradation for the loss-sensitive traffic. In addition to, TBP] scheme shows better performance than that of HOL scheme.