• Proceedings of the Korean Society of Computer Information Conference
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• 2017.01a
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• pp.13-14
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• 2017

본 논문에서는 강의 시간표 최적화를 위한 제약 프로그래밍의 적용 방안을 제시한다. 제약 프로그래밍은 제약 만족 문제를 해결하기 위한 기법으로 대상 문제를 결정 변수, 도메인, 제약조건으로 표현한다. 본 논문에서는 시간표 작성 최적화 문제의 결정 변수로 강의실, 요일, 교시를 사용하였으며, 추가로 요일과 교시를 결합한 변수를 사용함으로써 보다 쉽게 제약 조건을 표현할 수 있도록 하였다. 또한 제약 프로그래밍에 의해 도출된 초기해를 또 다시 제약 프로그래밍을 통해 반복적으로 개선함으로써 더 좋은 강의 시간표를 작성할 수 있도록 하였다. 특정 학과의 강의 시간표 문제를 대상으로 한 실험 결과, 본 논문에서 제안한 방법을 통해 보다 빠른 시간 내에 초기해를 도출할 수 있을 뿐 아니라 최종적으로 더 좋은 해의 도출이 가능함을 확인하였다.

• Journal of the Korean Society for Railway
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• v.7 no.4
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• pp.326-331
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• 2004

A routing is the path that an actual trainset follows as it moves from one train to another train in a timetable. The number of routings is equivalent to the number of trainsets required to cover the timetable. The primary factors of rolling stock requirement plan include evaluating the minimum number of routings. This can be formulated as a set partitioning problem and solved using enumeration method or column generation method. In this paper we presents an enumeration algorithm which is useful to implement the enumeration method for the rolling stock requirement plan.

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.137-139
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• 1993

This paper details methods used to verify the adquacy of a dc traction power supply for design in Seoul matropolitain subway Line-6 system. Examples of the approach are given for a major subway presently under construction. The performance of trains operating at maximum system design capacity is modelled using a train simulation program. Using a dc network analyser program, the maximum train operating timetable, and a model of the ac and dc electrical suppy system, the electrical performance of the entire system can be modelled over a 24-hour period. The results of this analysis are used to determime: train voltage at a level sufficient to ensure train schedules: adequacy of traction transformers, rectifier, and switchgear ratings; sizes of the overhead contact systern conductors, and ac and de feeder cables: and power and energy demands at the utility company's supply points for inital and final timetable operations.

• Journal of the Korea Society of Computer and Information
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• v.24 no.4
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• pp.27-34
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• 2019

The course timetabling problem is a kind of very complex combinatorial optimization problems, which is known as an NP-complete problem. Sometimes a given course timetabling problem can be accompanied by many constraints. At this time, even if only one constraint is violated, it can be an infeasible timetable. Therefore, it is very difficult to make an automated course timetabling system for a complex real-world course timetabling problem. This paper introduces an automated course timetabling system using constraint programming. The target problem has 26 constraints in total, and they are expressed as 24 constraints and an objective function in constraint programming. Currently, we are making a timetable through this system and applying the result to the actual class. Members' satisfaction is also much higher than manual results. We expect this paper can be a guide for making an automated course timetabling system.

• Journal of the Korean Society for Railway
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• v.12 no.2
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• pp.267-275
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• 2009

Max-plus algebra is a nonlinear system comprised of two operations, maximization (max) and addition (Plus), which are corresponding to the addition and the multiplication in conventional algebra, respectively. This methodology is applicable to many discrete event systems containing the state transition with the maximization and addition operation. Timetable with connection is one of such systems. We present the method based on max-plus algebra, which can make up timetable considering transfer and analyse its stability and robustness. In this study, it will be shown how to make up the timetable of the urban train and analyse its stability using Max-Plus algebra.

• Journal of the Korean Society for Railway
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• v.18 no.2
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• pp.149-156
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• 2015

It is necessary to determine real path for urban railway users in order to allocate revenues between urban railway organizations. Out of several algorithms used to determine optimal routes, the k-path algorithm based on link-label has been utilized. However, this k-path algorithm has certain flaws. For example, optimal route can change depending on the travel and walking time, transfer penalty, and so on. Also, this algorithm cannot take into account the characteristics of users, who prefer express train to normal trains. In this paper, an algorithm is proposed to determine one single optimal route based on the traffic card data. This method also can search for an optimal path in conjunction with the railway timetable.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10e
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• pp.499-501
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• 2002

현대 산업이 무선인터넷 산업구조, 이동통신 서비스 사업자 중심의 무선인터넷 사업 패러다임으로 변화되어 소형 임베디드(Embedded) 장비를 이용하여 장소의 제약없이 다양한 응용프로그램의 사용과 인터넷의 접속이 가능하게 되었다. 이에 본 논문에서는 플랫폼에 독립적인 자바기술을 이용하여 임베디드장비를 이용하여 지하철 운행시간 검색이란 응용프로그램을 구현하였다.

• Journal of the Korean Society for Railway
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• v.12 no.6
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• pp.1018-1023
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• 2009

This paper describes a reduction in the peaks of traction energy for metro railways in timetabling. We develope a mixed integer programming (MIP) model, which minimizes the number of trains running simultaneously. We suggest two approaches. In the first approach, we use the commercial MIP solver, CPLEX. In the second approach, we propose a heuristic algorithm. We apply both methods to the current daily timetable of the Korea Metropolitan Subway. We determine an optimal solution, which results in an improvement of approximately 25% over the current timetable.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.31
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• pp.81-106
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• 2006

The Terms of Reference are one of the most distictive features of ICC Arbitration. No document of this type is required to be drawn up under the rules of any of the other major international arbitration institutions. The purpose of this paper is to examine their advantages and to introduce main contents provided in Article 18 of ICC Rules of Arbitration, which results in the wide recognition of the Terms of Reference. As the volume of our international commercial transaction ranks almost ten in the world, the frequency using ICC Arbitration is expected to increase continuously. The Terms of Reference provide the parties and the arbitrators with an opportunity to identify and agree on procedural and other matters, such as the applicable law, the language of the arbitration and the timetable for the arbitration. They also afford the parties and the arbitrators to identify the substantive issues that are addressed in the arbitration and to delimit the precise scope of the Arbitract Tribunal's mandate. The contents of the Terms of Reference which are provided in Article 18(1) include the summary of parties claims, the list of issues and procedural rules. For the effects of the Terms of Reference, they are not intended to replace the parties' arbitration agreement. But they may in certain circumstances be regarded as a form of submission agreement. Article 18(2) provides that the Terms of Reference shall be signed by the parties and the Arbitral Tribunal, and requires the Arbitral Tribunal to transmit a signed copy of the Terms of Reference to the Court within two months of the date on which the file was transmitted to it by the Secretariat. The Court enjoys the power to extend the two-month time limit for the Terms of Reference on the reasoned request of the Arbitral Tribunal or on the Court's own initiative. Article 18(3) provides that if any of the parties refuses to take part in the drawing up of the Terms of Reference or to sign the same, they shall be submitted to the Court for approval. Article 18(4) allows the Arbitral Tribunal to extablish in a separate document a provisional timetable. This is a provision that encourages the acceleration of the arbitraction process. The timetable provided for therein is merely "provisional" and may be modified, as necessary, during the course of the arbitration.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.122-124
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• 2022

Handling Passenger Traffic is the main challenge for designing an elevator group-control algorithm. Advanced control systems such as Hyundai's Destination Selection System(DSS) lets passengers select the destination by pressing on a selecting screen, and the systems have shown great efficiency. However, the algorithm cannot be applied to the general elevator control system due to the expensive cost of the technology. Often many elevator systems use Nearest Car(NC) algorithms based on the SCAN algorithm, which results in time efficiency problems. In this paper, we designed an elevator group-control algorithm for specific buildings that have approximate timetable data for most of the passengers in the building. In that way, it is possible to predict the destination and the location of passenger calls. The algorithm consists of two parts; the waiting function and the assignment function. They evaluate elevators' actions with respect to the calls and the overall situation. 10 different timetables are created in reference to a real timetable following midday traffic and interfloor traffic. The specific coefficients in the function are set by going through the genetic algorithm process that represents the best algorithm. As result, the average waiting time has shortened by a noticeable amount and the efficiency was close to the known DSS result. Finally, we analyzed the algorithm by evaluating the meaning of each coefficient result from the genetic algorithm.