• Title/Summary/Keyword: Allocation problem

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A Study on the Storage Allocation of Container in Automated Container Terminals (자동화 컨테이너터미널에서 컨테이너의 장치 위치 결정에 관한 연구)

  • Jung Bong Jin;Choi Hyung Rim;Park Nam Kyu;Kwon Rae Kyoung
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2004.11a
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    • pp.281-286
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    • 2004
  • It's important to operate the yard for improving to the productivity in container terminal effectively. Because the automated container terminal(ACT) has storage yard of automation and horizon, it's character is different from conventional terminal. As the automation yard in ACT is operated by the automated equipments, it needs to an efficient storage plan which is connected the automated equipment, the external truck, the shipment etc.. Hut the traditional method of storage plan is the space assignment problem. The efficiency of yard decreases and it is brought about increase of shipment time, because real-time automated equipments and present yard status is not reflected in. In order to solve this problems, we propose the algorithm for real-time storage location of container considering shipment plan, yard status and the state of ATC.

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A Study on the Efficient Task Scheduling by the Reconstructed Task Graph (태스크 그래프의 재구성에 의한 효율적 태스크 스케줄링에 관한 연구)

  • Byun, Seung-Hwan;Yoo, Kwan-Jong
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.9
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    • pp.2235-2246
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    • 1997
  • This paper presents an effective heuristic task scheduling algorithm for multiprocessor systems. To execute task scheduling effectively which is defined as an allocation of m's tasks onto n's processors(m > n), several problems almost at NP-hard should be cleaned up. The purpose of the task scheduling obtains the minimum execution time by mapping the tasks on a system topology or reduces the total execution time to give a minimum system topology. In order to solve this problem, in this paper, the task scheduling is done by redefining a task graph to a reconstructed task graph (RTG). An RTG is obtained by merging or copying nodes to equal the number of nodes on each level of the task graph to the number of processors of the system topology and then directly scheduled to the system topology. This method obtains a fast scheduling time and a simple scheduling method, and near-optimal execution time without executing steps such as the refinement step and the duplication step after the task scheduling.

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Optimal scheduling of multiproduct batch processes with various due date (다양한 납기일 형태에 따른 다제품 생산용 회분식 공정의 최적 생산계획)

  • 류준형
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.844-847
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    • 1997
  • In this paper, scheduling problem is dealt for the minimization of due date penalty for the customer order. Multiproduct batch processes have been dealt with for their suitability for high value added low volume products. Their scheduling problems take minimization of process operation for objective function, which is not enough to meet the customer satisfaction and the process efficiency simultaneously because of increasing requirement of fast adaptation for rapid changing market condition. So new target function has been suggested by other researches to meet two goals. Penalty function minimization is one of them. To present more precisely production scheduling, we develop new scheduling model with penalty function of earliness and tardiness We can find many real cases that penalty parameters are divergent by the difference between the completion time of operation and due date. That is to say, the penalty parameter values for the product change by the customer demand condition. If the order charges different value for due date, we can solve it with the due date period. The period means the time scope where penalty parameter value is 0. If we make use of the due date period, the optimal sequence of our model is not always same with that of fixed due date point. And if every product have due date period, due date of them are overlapped which needs optimization for the maximum profit and minimum penalty. Due date period extension can be enlarged to makespan minimization if every product has the same abundant due date period and same penalty parameter. We solve this new scheduling model by simulated annealing method. We also develop the program, which can calculate the optimal sequence and display the Gantt chart showing the unit progress and time allocation only with processing data.

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Call Admission Control Techniques of Mobile Communication System using SRN Models (SRN 모델을 이용한 이동통신 시스템의 호 수락 제어 기법)

  • 로철우
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.39 no.12
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    • pp.529-538
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    • 2002
  • Conventional method to reduce the handoff call blocking probability(PBH) in mobile communication system is to reserve a predetermined number of channels only for handoff calls. To determine the number of reserved channels, an optimization problem, which is generally computationally heavily involved, must be solved. In this Paper, we propose a call admission control (CAC) scheme that can be used to reduce the PBH without reserving channels in advance. For this, we define a new measure, gain, which depends on the state of the system upon the arrival of a new call. The proposed CAC decision rule relies on the gain computed when a new call arrives. SRN, an extended stochastic Petri nets, provides compact modeling facilities for system analysis can be calculated performance index by appropriate reward to the model. In this Paper, we develop SRN models which can perform the CAC with gain. The SRN models are 2 level hierarchical models. The upper layer models are the structure state model representing the CAC and channel allocation methods considering QoS with multimedia traffic The lower layer model Is to compute the gain under the state of the upper layer models.

System Dynamics Modeling for Policy Analysis of Occupational Injuries

  • Lee, Kyung-Soo;Nam, Seok-Woo;Chung, Hee-Tae
    • Journal of Korean Clinical Health Science
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    • v.2 no.2
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    • pp.126-132
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    • 2014
  • Purpose. Because traditional statistics approach had limitations in learning future forecasting and major factors causing occupational injuries in each industry, this paper develops a model forecasting and evaluating occupational injury rate by using a system dynamics model through the analysis of the industry injury statistics and the project for industry injury prevention. Method. The model of this paper consists of 12 total models such as a model of employees, of industrial disaster victims, of injury rate, etc.; In the analysis of firm size, it is classified and developed according to 12 groups on the basis of the number of employees, and in the analysis of industrial classification, it is done according to 10 total business fields such as manufacturing business, construction one, etc. Results. This paper suggests the methodology which forecasts industry injury rate by business field and size on the basis of developed model, and evaluates an industry injury prevention project from various angles. Conclusions. This paper deduced problem through the analysis of an industry injury by business fields and a comparative analysis of foreign cases, and analyzed to affect industry injury prevention by industry. And it also analyzed actual condition of industry injury, and did a difference in the level of safety consciousness according to the general characteristics of workers and occupational safety and health education related characteristics. In result, this paper suggests that analyzing occupational injury related factors, a safety budgetary allocation, and industry injury related factors can reduce illness costs such as employees' injury and medical care, and also assist cost for a disability.

Joint Space-time Coding and Power Domain Non-orthogonal Multiple Access for Future Wireless System

  • Xu, Jin;Ding, Hanqing;Yu, Zeqi;Zhang, Zhe;Liu, Weihua;Chen, Xueyan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.1
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    • pp.93-113
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    • 2020
  • According to information theory, non-orthogonal transmission can achieve the multiple-user channel capacity with an onion-peeling like successive interference cancellation (SIC) based detection followed by a capacity approaching channel code. However, in multiple antenna system, due to the unideal characteristic of the SIC detector, the residual interference propagated to the next detection stage will significantly degrade the detection performance of spatial data layers. To overcome this problem, we proposed a modified power-domain non-orthogonal multiple access (P-NOMA) scheme joint designed with space-time coding for multiple input multiple output (MIMO) NOMA system. First, with proper power allocation for each user, inter-user signals can be separated from each other for NOMA detection. Second, a well-designed quasi-orthogonal space-time block code (QO-STBC) was employed to facilitate the SIC-based MIMO detection of spatial data layers within each user. Last, we proposed an optimization algorithm to assign channel coding rates to balance the bit error rate (BER) performance of those spatial data layers for each user. Link-level performance simulation results demonstrate that the proposed time-space-power domain joint transmission scheme performs better than the traditional P-NOMA scheme. Furthermore, the proposed algorithm is of low complexity and easy to implement.

Algorithm for Arthmetic Optimization using Carry-Save Adders (캐리-세이브 가산기를 이용한 연산 최적화 알고리즘)

  • Eom, Jun-Hyeong;Kim, Tae-Hwan
    • Journal of KIISE:Computer Systems and Theory
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    • v.26 no.12
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    • pp.1539-1547
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    • 1999
  • 캐리-세이브 가산기 (CSA)는 회로 설계 과정에서 빠른 연산 수행을 위해 가장 널리 이용되는 연산기 중의 하나이다. 그러나, 현재까지 산업체에서 CSA를 이용한 설계는 설계자의 경험에 따른 수작업에 의존하고 있고 그 결과 최적의 회로를 만들기 위해 매우 많은 시간과 노력이 소비되고 있다. 이에 따라 최근 CSA를 기초로 하는 회로 합성 자동화 기법에 대한 연구의 필요성이 대두되고 있는 상황에서, 본 논문은 연산 속도를 최적화하는 효율적인 CSA 할당 알고리즘을 제안한다. 우리는 CSA 할당 문제를 2단계로 접근한다: (1) 연산식의 멀티 비트 입력들만을 고려하여 최소 수행 속도 (optimal-delay)의 CSA 트리를 할당한다; (2) (1)에서 구한 CSA 트리의 수행 속도 증가가 최소화 (minimal increase of delay) 되는 방향으로 CSA들의 캐리 입력 포트들에 나머지 싱글 비트 입력들을 배정한다. 실제 실험에서 우리의 제안된 알고리즘을 적용하여 연산식들의 회로 속도를 회로 면적의 증가 없이 상당한 수준까지 줄일 수 있었다.Abstract Carry-save-adder (CSA) is one of the most widely used implementations for fast arithmetics in industry. However, optimizing arithmetic circuits using CSAs is mostly carried out by the designer manually based on his/her design experience, which is a very time-consuming and error-prone task. To overcome this limitation, in this paper we propose an effective synthesis algorithm for solving the problem of finding an allocation of CSAs with a minimal timing for an arithmetic expression. Specifically, we propose a two step approach: (1) allocating a delay-optimal CSA tree for the multi-bit inputs of the arithmetic expression and (2) determining the assignment of the single-bit inputs to carry inputs of the CSAs which leads to a minimal increase of delay of the CSA tree obtained in step (1). For a number of arithmetic expressions, we found that our approach is very effective, reducing the timing of the circuits significantly without increasing the circuit area.

Software Quality Classification Model using Virtual Training Data (가상 훈련 데이터를 사용하는 소프트웨어 품질 분류 모델)

  • Hong, Euy-Seok
    • The Journal of the Korea Contents Association
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    • v.8 no.7
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    • pp.66-74
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    • 2008
  • Criticality prediction models to identify most fault-prone modules in the system early in the software development process help in allocation of resources and foster software quality improvement. Many models for identifying fault-prone modules using design complexity metrics have been suggested, but most of them are training models that need training data set. Most organizations cannot use these models because very few organizations have their own training data. This paper builds a prediction model based on a well-known supervised learning model, error backpropagation neural net, using design metrics quantifying SDL system specifications. To solve the problem of other models, this model is trained by generated virtual training data set. Some simulation studies have been performed to investigate feasibility of this model, and the results show that suggested model can be an alternative for the organizations without real training data to predict their software qualities.

ALLOCATION AND PRICING IN PUBLIC TRANSPORTATION AND THE FREE RIDER THEOREM

  • Beckmann, Martin J.
    • Journal of the Korean Operations Research and Management Science Society
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    • v.3 no.1
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    • pp.31-46
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    • 1978
  • Consider a time interval during which the demand for trips is fixed (e.g. the rush hour period). The traveller has a choice between various public modes, whose travel times and fares are fixed, and the automobile mode, for which travel time and cost depend on the volume of traffic flow on those roads, which are subject to congestion. We consider the equilibrium in terms of a representative travellerm, who choses for any trip the mode and route with the least combined money and time cost. When several (parallel) model or routes are chosen, then the combined cost of money and time must be equal among these. Our problem is first, to find the optimal flows of cars and of public mode carriers on the various links of their networks and second the optimal fares for trips by the variousmodes. The object is to minimize the total operating costs of the carriers and car plus the total time costs to travellers. The optimal fares are related to, but not identical with the dual variables of the underlying Nonlinear Program. They are equal to these dual variables only in the case, when congestion tolls on trips or on the use of specific roads are collected from automobile users. When such tolls are not collected, they must be passed on as subsidies to travellers using competing modes. The optimal fares of public modes are then reduced by the amounts of these subsidies. Note that subsidies are not a flat payment to public carriers, but are calculated on the basis of tickets sold. Fares and subsidies depend in general on tile period considered. They will be higher during periods of higher demand. When the assumption of fixed trip demand is relaxed, this tare system is no longer best, but only second best since too much traffic will, in general, be generated. The Free Rider Theorem states the following : Suppose road tolls can be charged, so that a best pricing system for public modes is posssible. Then there may exist free rides on some routes and modes, but never on a complete round trip.

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Regional Difference of Health Care Utilitzation in Korea (의료이용의 지역간 격차 -3차성 내과계 진단군을 중심으로-)

  • 신영전;이원영;문옥륜
    • Health Policy and Management
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    • v.9 no.1
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    • pp.72-109
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    • 1999
  • This study is conducted to investigate the current status on the utilization of health care and plan for solving this problem. The claims data of the fiscal tear 1995 obtained from the regional health insurance society are used for the study. The main findings of the study are summarized as follows. Indexes(The Extremal Quotient(EQ), coefficients of variance(CV's))which represent the regional difference in the admission rate of the tertiary medical diagnosis group report that there is difference in quantity and quality of utilization of health care. The admission rate is lower in the big city areas, Kyoungkido, Kangwondo and Chunlapukdo. Even after age-sex adjustment, the admission rate is still low in Kangwondo, Chunlapukdo and Kyoungsangpukdo. The big city areas tend to have higher rates in the expenses per claim, hospital days per claim, and daily expenses but the rates are still low in some area in Kangwondo, Chunlanamdo and Kyoungsangpukdo. This result remains as same after age-sex adjustment. There is a large regional difference in average utilization rate for the tertiary hospital of the tertiary medical diagnosis group: 57.2%(SD 11.53). The utilization rates for the tertiary hospital in their large catchment area are 96.34%, 83.19% and 73.22% in each Kyoungin, Kyoungnam and Kyoungpuk areas whereas it is lower in a Chungpuk and Chungnam areas. The regional differences of health care utilization of the tertiary medical diagnosis group gave some relationships with their geographical characteristics such as socio-economic characteristics and supply factors of medical services. It is important that many medical policies should be developed in order to minimize and balance out the regional differences of health care utilization. The service allocation policy should include the reconstruction of manpower policy, developing the resource allocating formula, finding the self-sufficient catchment area and reforcing of public health services. Moreover, in order to achieve the balanced development by region, they should investigate and consider each county's microscopic properties under the consistent macrocopic policy. The further studies to find causes of regional difference are needed.