• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.1166-1170
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• 2010

In the case of railway freight, there's a lot of process at railway freight terminal. In these days, for operation efficiency improvement, Load/Unload planning is being carried out research. Load/unload problem can be classified as track assignment, container assignment, yard truck route problem, unload equipment scheduling, container yard plan. In this paper, we focus on track assignment and container assignment among the load/unload problem. we analysis information architecture to solve this problem. And we compares two precesses for existing method and optimization method of track/container assignment processes. An contents different analysis of two methods can shows reformation of an information architecture for load/unload process in the railway freight terminal.

• 한국군사과학기술학회지
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• 제9권4호
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• pp.24-31
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• 2006

To reduce the interferences between the radio equipments which are operated in frequency hopping mode, the frequency resource should be assigned to each equipment without overlapping when several groups of radio equipments operate in the same area. If the radio equipments are in a different area, the partial frequency overlaying can be permitted. From the isotropic multi-dimensional array, several frequency assignment tables can be extracted for a same area. Also several tables can be extracted for different areas. Since there can be no overlapped frequencies between the tables for the same area, no interference between the radio equipments in an area is guaranteed. The frequencies overlapped between 2 tables for 2 different areas are pre-planed as required. The interference performance in frequency hopping radio can be controlled as desired using the proposed Frequency Resource Assignment Algorithm using Isotropic multi-dimensional Array.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권4호
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• pp.1535-1554
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• 2016

This paper proposes a novel channel assignment scheme called multi-cluster based dynamic channel assignment (MC-DCA) to improve system performance for the downlink of dense femtocell networks (DFNs) based on orthogonal frequency division multiple access (OFDMA) and frequency division duplexing (FDD). In order to dynamically assign channels for femtocell access points (FAPs), the MC-DCA scheme uses a heuristic method that consists of two steps: one is a multiple cluster assignment step to group FAPs using graph coloring algorithm with some extensions, while the other is a dynamic subchannel assignment step to allocate subchannels for maximizing the system capacity. Through simulations, we first find optimum parameters of the multiple FAP clustering to maximize the system capacity and then evaluate system performance in terms of the mean FAP capacity, unsatisfied femtocell user equipment (FUE) probability, and mean FAP power consumption for data transmission based on a given FUE traffic load. As a result, the MC-DCA scheme outperforms other schemes in two different DFN environments for commercial and office buildings.

• 한국국방경영분석학회지
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• 제25권1호
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• pp.142-159
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• 1999

To assign the soldiers in the adequate positions I military is almost as important as managing officers because they compose the main part of military structure and equipment operators. The current Military Occupational Specialty(MOS) assignment system lacks the capability to optimize the use of recruit's potential. We suggest an MOS assignment method for enlisted recruits using the Analytic Hierarchy Process(AHP) method, this method systematically provides a method of calculation of composite relative weights of decision elements to be considered during MOS assignment and a method of quantification for personal quality of new recruits. The quantified value of personal quality, Mission Performance Capability(MPC), in this study means the mission performance capability when a personnel is assigned to a certain MOS. This paper develops a multiple objectives MOS assignment model for enlisted recruits. It uses MPC of personnels, calculated with AHP method and consensus method, as parameters. The goal constraints are assurance of filling requirement, minimization of the number of unassigned personnel to MOS, capability satisfaction of education facility and support facility, assurance of desired MPC value level for MOS assignment, and maximization of total MPC. The objective function is to terminalization of the negative or positive deviation for the above goal constraints.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2005년도 추계학술대회 및 정기총회
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• pp.321-333
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• 2005

With the limited frequency spectrum and an increasing demand for cellular communication services, the problem of channel assignment becomes increasingly important. However, finding a conflict free channel assignment with the minimum channel span is NP hard. As demand for services has expanded in the cellular segment, sever innovations have been made in order to increase the utilization of bandwidth. The innovations are cellular concept, dynamic channel assignment and hierarchical network design. Hierarchical network design holds the public eye because of increasing demand and quality of service to mobile users. We consider the frequency assignment problem and the base station placement simultaneously. Our model takes the candidate locations emanating from this process and the cost of assigning a frequency, operating and maintaining equipment as an input. In addition, we know the avenue and demand as an assumption. We propose the network about the profit maximization. This study can apply to GSM(Global System for Mobile Communication) which has 70% portion in the world. Hierarchical network design using GA(Genetic Algorithm) is the first three-tier (Macro, Micro, Pico) model, We increase the reality through applying to EMC (Electromagnetic Compatibility Constraints). Computational experiments on 72 problem instances which have 15${\sim}$40 candidate locations demonstrate the computational viability of our procedure. The result of experiments increases the reality and covers more than 90% of the demand.

• 한국항해항만학회지
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• 제32권8호
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• pp.621-628
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• 2008

지속적인 컨테이너 물동량의 증가와 컨테이너선의 대형화에 따라서 항만간의 경쟁은 점점 치열해지고 있다. 주요 항만 하역장비 제조사들은 획기적인 생산성 향상을 제공할 수 있는 새로운 개념의 하역장비 개발에 많은 관심을 기울이고 있다. 본 연구에서는 항만의 대표적 하역장비인 컨테이너 크레인에 대해서 다양한 개발 대안들이 존재할 때, 최적의 개발 대안을 선정하는 절차를 제시한다. 절차는 두 단계로 구성되는데, 첫 번째 단계에서는 요구되는 필수요소들을 만족하지 못하는 대안을 제거하고 두 번째 단계에서는 전문가의 평가와 선형 할당법을 적용하여 최종적인 개발 대안을 선정한다. 마지막으로, 제시한 절차를 적용한 사례를 제시한다.

• 산업경영시스템학회지
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• 제46권4호
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• pp.294-303
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• 2023

During wartime, the operation of engineering equipment plays a pivotal role in bolstering the combat prowess of military units. To fully harness this combat potential, it is imperative to provide efficient support precisely when and where it is needed most. While previous research has predominantly focused on optimizing equipment combinations to expedite individual mission performance, our model considers routing challenges encompassing multiple missions and temporal constraints. We implement a comprehensive analysis of potential wartime missions and developed a routing model for the operation of engineering equipment that takes into account multiple missions and their respective time windows of required start and completion time. Our approach focused on two primary objectives: maximizing overall capability and minimizing mission duration, all while adhering to a diverse set of constraints, including mission requirements, equipment availability, geographical locations, and time constraints.

• 기술혁신학회지
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• 제3권3호
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• pp.53-66
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• 2000

This study analyses the actual conditions and efficiency of supplier relations of If equipment industries of Korea. The fact-finding survey we conducted includes PCs, mobile phone handsets, and public switching equipments. The survey shows that there is room for improvement in the aspect of assignment of roles among suppliers in R&D activities.

• 한국항해학회지
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• 제13권1호
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• pp.55-61
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• 1989

Nowadays much efforts for evaluating the productivity of port physical distribution system to meet the rapid change of the port and shipping circumstances has been made continuously all over the world. The major part of these efforts is the improvement of the productivity of cargo handling system. The cargo equipment system as infrastructure in the cargo handling system is organized well in some degrees, but the management system of manpower as upper structure is still remained in an insufficient degree. There is little study, so far, on a systematic research for the management of port labor gang, and even those were mainly depended on rule of thumb. The object of this study is to introduce the method of optimal allocation and assignment for the labor gang in single ship, which was suggested as a first stage in dealing with them generally. The problem of optimal allocation and assignment of the labor gang can be (I) formalized with multi-stage allocation and assignment of the labor gang can be. (II) dealt with two stages in form of hierarchic structure and moreover, (III) The optimal size of labor gang was obtained through dynamic programming from the point of minimizing the summation of labor gang in every stage, (IV) For the problem of optimal assignment, the optimal policy was determined at the point of minimizing the summation of movement between hatches.

• 한국통신학회논문지
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• 제38B권4호
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• pp.257-265
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• 2013

본 연구에서는 펨토 기지국 (Access Point: AP) 밀도가 높은 Orthogonal Frequency Division Multiple Access (OFDMA) 기반 펨토셀 네트워크 환경에서 하향링크 시스템 성능 향상을 위한 그래프 컬러링 기반 동적채널할당 (Graph Coloring based Dynamic Channel Assignment: GC-DCA) 방법을 연구한다. 제안하는 GC-DCA는 그래프 컬러링을 이용한 펨토 AP 그룹화 단계와 펨토 사용자 단말 (User Equipment: UE)의 신호 대 잡음비 (Signal to Interference plus Noise Ratio: SINR)을 고려한 동적채널할당 단계로 구성된다. 시뮬레이션을 통해 평균 펨토 UE 전송률과 펨토 UE 가 요구하는 전송률을 만족하지 못하는 펨토 UE 확률을 분석한 후, 제안하는 GC-DCA 가 다른 채널할당 방법들 보다 우수함을 보인다.