• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.2
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• pp.57-71
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• 2023

In this study, we analyze a finite-buffer M/G/1 queueing model with randomized pushout space priority and nonpreemptive time priority. Space and time priority queueing models have been extensively studied to analyze the performance of communication systems serving different types of traffic simultaneously: one type is sensitive to packet delay, and the other is sensitive to packet loss. However, these models have limitations. Some models assume that packet transmission times follow exponential distributions, which is not always realistic. Other models use general distributions for packet transmission times, but their space priority rules are too rigid, making it difficult to fine-tune service performance for different types of traffic. Our proposed model addresses these limitations and is more suitable for analyzing communication systems that handle different types of traffic with general packet length distributions. For the proposed queueing model, we first derive the distribution of the number of packets in the system when the transmission of each packet is completed, and we then obtain packet loss probabilities and the expected number of packets for each type of traffic. We also present a numerical example to explore the effect of a system parameter, the pushout probability, on system performance for different packet transmission time distributions.

• Journal of Arbitration Studies
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• v.17 no.2
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• pp.43-70
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• 2007

The purpose of this paper is to make research on the contents and discussions of the draft of revised UNCITRAL Arbitration Rules that have been discussed and considered by the Working Group. At its thirty-ninth session (New York, 19 June-7 July 2006), the Commission agreed that, in respect of future work of the Working Group, priority be given to a revision of the UNCITRAL Arbitration Rules (1976). At its forty-fifth session (Vienna, 11-15 September 2006), the Working Group undertook to identify areas where a revision of the UNCITRAL Arbitration Rules might be useful. At that session, it was considered that the focus of the revision should be on updating the Rules to meet changes that had taken place over the last thirty years in arbitral practice. The largely amended provisions of the draft of revised UNCITRAL Arbitration Rules are as follows : Notice of arbitration and response to the notice of arbitration (Article 3), Designating and appointing authorities (Article 4 bis), November of arbitrators (Article 5), Appointment of arbitrations (Article 6), Appointment of arbitrators in multi-party arbitration (Article 7 bis), Challenge of arbitrators (Article 9), Replacement of an arbitrator (Article 13), Pleas as to the jurisdiction of the arbitral tribunal (Article 21), Interim measures (Article 26), Form and effect of the award (Article 32), and Liability of arbitrators (Proposed additional provisions). There are some differences between the draft of revised UNCITRAL Arbitration Rules and the KCAB Arbitration Rules. In order to jnternationalize the Korea's commercial arbitration system, it is desirable that the main articles of the draft of revised UNCITRAL Arbitration Rules should be admitted to the KCAB Arbitration Rules. In conclusion, the Commission was generally of the view of any revision of the UNCITRAL Arbitration Rules should not alter the structure of the text, its spirit, its drafting style, and should respect the flexibility of the text rather than make it more complex. The Working Group agreed that harmonizing the provisions of the UNCITRAL Model Law should not be automatic but rather considered only where appropriate.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.3
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• pp.78-86
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• 2015

Up-to-date business environment for manufacturers is very complex and rapidly changing. In other words, companies are facing a variety of changes, such as diversifying customer requirements, shortening product life cycles, and switching to small quantity batch production. In this situation, the companies are introducing the concept of JIT (just-in-time) to solve the problem of on-time production and on-time delivery for survival. Though many companies have introduced ERP (enterprise resource planning) systems and MRP (material requirement planning) systems, the performance of these systems seems to fall short of expectations. In this paper, the case study on introducing an APS (advanced planning and scheduling) system based on dispatching rules to a machining company and on finding a method to establish an efficient production schedule is presented. The case company has trouble creating an effective production plan and schedule, even though it is equipped with an MRP-based ERP system. The APS system is applied to CNC (computer numerical control) machines, which are key machines of the case company. The overall progress of this research is as follows. First, we collect and analyze the master data on individual products and processes of the case company in order to build a production scheduling model. Second, we perform a pre-allocation simulation based on dispatching rules in order to calculate the priority of each order. Third, we perform a set of production simulations applying the priority value in order to evaluate production lead time and tardiness of pre-defined dispatching rules. Finally, we select the optimal dispatching rule suitable for work situation of the case company. As a result, an improved production schedule leads to an increase in production and reduced production lead time.

• Journal of Arbitration Studies
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• v.18 no.2
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• pp.3-31
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• 2008

At its thirty-ninth session(New York, 19 June - 7 July 2006), United Nations Commission on International Trade Law(hereinafter referred to as the Commission) agreed to give priority to the topic of revising the UNCITRAL Arbitration Rules. From the forty-fifth through the forty-seventh session, the Working Group checked various issues based on the draft revised version of the UNCITRAL Arbitration Rules prepared by the Secretariat. At its forty-eighth session, the Working Group is going to finish its first reading of articles 38 to 41 of the draft revised version of the UNCITRAL Arbitration Rules, and to commence its second reading of the draft revised version of UNCITRAL Arbitration Rules. Korea is keen on enticing foreign direct investment into its territory. From the 1960s, Korea has concluded more than 80 BITs. Korea is making efforts to conclude FTAs with its trading partners. As of January, 2008, 3 FTAs have taken into effect with respect to Korea. According to provisions on dispute settlement found in such BITs and FTAs involving Korea, the Rules can be chosen for Investor-State Arbitration. Furthermore, the Rules is followed by the arbitration rules for domestic and international arbitrations administered by the Korean Commercial Arbitration Board. If the Commission adopts the revised version of UNCITRAL Arbitration Rules, the Rules will be able to give impact on the arbitration law and practice around the world of arbitration. That is the reason why we should keep attention to the development of the deliberations of the Working Group.

• Journal of the military operations research society of Korea
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• v.17 no.2
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• pp.113-122
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• 1991

This paper presents the Allocation Priority Scheme (APS) for multiprocessor system. The objective of APS is to reduce the time-complexity on a Physical Mapping Scheme(PMS). The PMS is to allocate the nodes of the Data Dependency Graph (DDG) to the multprocessors efficiently and effectively. The APS provides the priority to each node (vertex) in the DDG. In other words, the goal of the APS is to find a request resource mapping such that the total cost (time-complexity) is minimized. The special case in which all requests have equal priorities and all resoruces have equal precedences, and the comparisons between our APS and other schems are discussed in the paper. The APS provides the heuristic rules which are based on maximum height (MH), number of children nodes ($N_c$), number of father nodes ($N_f$), and computation time ($T_c$). The estimation moth of the computaion time is in the paper.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.451-456
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• 2004

This study was performed to analyze the operation system of transfer crone to improve the reality of yard operation roles in container terminal and present the applicable method of operation rules to apply the operation priority. And we derived the procedure to estimate the maximum number of waiting truck based on the waiting of truck and the occupancy of driving lane in yard, and analyzed the constraint state of space. To solve the space constraint, we provided a multi-job principle to define the space resource and described the solution and sequence diagram for the principle.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.43
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• pp.81-89
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• 1997

This study is concerned with the scheduling problems in flexible manufacturing systems(FMSs). The scheduling problem in FMSs is a complex one when the number of machines and jobs are increased. Thus, a heuristic method is recommended in order to gain near-optimal solutions in a practically acceptable time. The purpose of this study is to develope a machine and AGV dispatching algorithm. The proposed dispatching algorithm is a on-line scheduling algorithm considering the due date of parts and the status of the system in the scheduling process. In the new machine and AGV dispatching algorithm, a job priority is determined by LPT/LQS rules considering job tardiness. The proposed heuristic dispatching algorithm is evaluated by comparison with the existing dispatching rules such as LPT/LQS, SPT/LQS, EDD/LQS and MOD/LQS. The new dispatching algorithm is predominant to existing dispatching rules in 100 cases out of 100 for the mean tardiness and 89 cases out of 100 for the number of tardy jobs.

• Journal of architectural history
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• v.28 no.6
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• pp.19-30
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• 2019

This study explores the application aspect of The detailed rules of Census (1896) through the change of Kan numbers in Gyeonpyeong-bang. Although Gyeonpyeong-bang was a high-priority area because of its location, it was difficult to trace the operation of the urban situation due to lack of data. This study is focusing on restoring space and society in the Gyeonpyeong-bang using the information on the type of houses and the number of Kan listed in the family register of Hanseong-bu. The detailed rules of Census sets out provisions for the family registry and the rules of making Tong. Especially when it comes to the rules of making Tong, this rule deals with the code of making ten Hos into one Tong. This study was conducted by dividing the status of the Tong into three types: uncompleted Tong, exceeded Tong without vacant Ho number, and exceeded Tong with the vacant Ho number. Since these three types of Tong are in the process of change towards the complete Tong with 10 Hos, they were thought to be able to demonstrate the specific application of the rules. This study will be meaningful as a case study that expands the point of existing research on the Tong making rules, which was not focused relatively on restoring urban conditions at that time, by looking at the changes in exceptions that deviated from the Sipgajaktong rule.

• Management Science and Financial Engineering
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• v.17 no.1
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• pp.79-94
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• 2011

Team orienteering, an extension of single-competitor orienteering, is the problem of determining multiple paths from a starting node to a finishing node for a given allowed time or distance limit fixed for each of the paths with the objective of maximizing the total collected score. Each path is through a subset of nodes, each of which has an associated score. The team orienteering problem has many applications such as home fuel delivery, college football players recruiting, service technicians scheduling, military operations, etc. Unlike existing optimal and heuristic algorithms often leading to heavy computation, this paper suggests two types of priority rule based heuristics-serial and parallel ones-that are especially suitable for practically large-sized problems. In the proposed heuristics, all nodes are listed in an order using a priority rule and then the paths are constructed according to this order. To show the performances of the heuristics, computational experiments were done on the small-to-medium sized benchmark instances and randomly generated large sized test instances, and the results show that some of the heuristics give reasonable quality solutions within very short computation time.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.54 no.4
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• pp.177-184
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• 2005

This paper proposes a improved investment priority decision method of the facilities considering the reliability of distribution networks. The proposed method decides a investment order of the facilities combining, by fuzzy rules, the investment priority decision of KEPCO and the priority decision considering reliability evaluation indices. Where reliability evaluation indices are SAIFI(System Average Interruption Frequency Index) and SAIDI(System Average Interruption Duration Index), as referred to evaluation index for sustained interruption. The reliability analysis method of distribution networks applied in this paper utilizes analytic method, where the used reliability data is historical data of KEPCO. Particularly, we assumed that the failure rate increased as the equipment ages. To verify the performance of the proposed method, we applied it with the planned projects to reinforce the weak facility electrical facilities in KEPCO in 2004. The evaluation result showed that, under a limited budget, the reliability of the KEPCO in the Busan region using the proposed method can be enhanced than using the conventional KEPCO's method. Therefore, the results verify the proposed method can be efficiently used in the actual priorities method for investing the electrical facilities.