• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.10a
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• pp.527-530
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• 2004

This paper presents an optimization formulation for resource scheduling in Critical Resource Diagramming (CRD) of production scheduling networks. A CRD network schedules units of resources against points of needs in a production network rather than the conventional approach of scheduling tasks against resource availability. This resource scheduling approach provides more effective tracking of utilization of production resources as they are assigned or 'moved' from one point of need to another. Using CRD, criticality indices can be developed for resource types in a way similar to the criticality of activities in Critical Path Method (CPM). In our supply chain model, upstreams may choose either normal operation or expedited operation in resource scheduling. Their decisions affect downstream's resource scheduling. The suggested optimization formulation models resources as CRD elements in a production two-stage supply to minimize the total operation cost

• Journal of Navigation and Port Research
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• v.30 no.7
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• pp.561-566
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• 2006

In this paper, we propose a new ship scheduling set packing model considering limited risk or variance. The set packing model is used in many applications, such as vehicle routing, crew scheduling, ship scheduling, cutting stock and so on. As long as the ship scheduling is concerned, there exits many unknown external factors such as machine breakdown, climate change and transportation cost fluctuation. However, existing ship scheduling models have not considered those factors apparently. We use a quadratic set packing model to limit the variance of expected cost of ship scheduling problems under stochastic spot rates. Set problems are NP-complete, and additional quadratic constraint makes the problems much harder. We implement Kelley's cutting plane method to replace the hard quadratic constraint by many linear constrains and use branch-and-bound algorithm to get the optimal integral solution. Some meaningful computational results and comments are provided.

• IE interfaces
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• v.19 no.3
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• pp.202-213
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• 2006

In this paper, we develop a planning system for the routing and scheduling of vehicles in pickup and delivery service such as door-to-door parcel service. Efficient routing and scheduling of vehicles is very important in pickup and delivery service. The routing and scheduling problem is a variation of vehicle routing problem which has various realistic constraints. We develop a heuristic algorithm based on tabu search to solve the routing and scheduling problem. We develop a routing and scheduling system installed the algorithm as a planning engine. The system manage the basic data and uses GIS data to make a realistic route plan.

• Journal of Industrial Technology
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• v.18
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• pp.139-148
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• 1998

Traditionally, the problems of manufacturing technology and manufacturing management have been treated independently. In this research, we endeavor to integrate the process planning and scheduling activities as an attempt to integrate the two realms. To draw up a plan of process planning and scheduling in real manufacturing environment is not an easy task because available time to plan could be limited and the shop status could change frequently. So we propose an architecture of integrated process planing and scheduling problem within the allowed time even if sheep situations change rather frequently. We argue that we can obtain a better and practical scheduling solution by dynamically changing the processing machines and operations as the shop condition changes. The proposed system takes the initial information for alternative machines and operations represented by an AND/OR graph as its input. Other informational inputs to the system are part order and shop statues. The system then generates new process plan and schedules during permitted time. Experimental results show that the proposed scheme provides a viable solution for real world scheduling problems.

• The Transactions of the Korea Information Processing Society
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• v.4 no.10
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• pp.2571-2580
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• 1997

In this paper, we deal with the resource constrain scheduling to execute behavior algorithm under resource limit. Expecially, we proposed a scheduling algorithm, called delayed scheduling, which finds the lower bound control step to assign operation under resource limit. We take in account the actual scheduling problems including multicycle operation and functional pipelining. Integer Linear Programing formulations are used to the scheduling problems in order to get optimal scheduling result. Experiment was done on the DFG model of fifth-order digital wave filter, to show it's effectiveness.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.2
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• pp.167-174
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• 2005

This paper experimentally validates the efficacy of scheduling method that satisfies the performance requirement of periodic data in the Foundation Fieldbus. The scheduling method allocates periodic data traffic to a bandwidth-limited fieldbus medium. The scheduling method generates schedule list that records schedule starting time and schedule period of each periodic data. This study developed an experimental model of a Foundation Fieldbus network system. Using the experimental model, this study showed that the scheduling method can be easily implemented in a practical Foundation Fieldbus network system. The results obtained from the experimental evaluation showed that the scheduling method restricts the delay of periodic data to a pre-specified bound.

• Journal of the Korea Society of Computer and Information
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• v.23 no.9
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• pp.43-50
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• 2018

In this paper, we propose a hexagon model-based efficient beacon frame scheduling approach for wireless sensor networks. The existing beacon frame scheduling approaches use a lot of slots and subslots for the beacon frame scheduling. Thus, the data from source nodes are not efficiently delivered to a sink node. Also in case a sink node needs to broadcast a beacon frame to the nodes in the network, delivering the beacon frame to the network nodes is not efficient as well. Thus, to solve the problem, we use a hexagon model to find the number of slots and subslots for the beacon frame scheduling. By using them for the beacon frame scheduling, the proposed approach performs better than other approaches in terms of the data transmission delay, the number of received data, the beacon transmission delay and the number of relaying the beacon frames.

• Journal of the Korean Society of Systems Engineering
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• v.17 no.2
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• pp.1-8
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• 2021

This study proposes a systems engineering approach for the development of an advanced planning & scheduling (APS) system for a cosmetic case manufacturing factory. The APS system makes production plans and schedules based on the injection process, which consists of 27 plastic injection machines in parallel to control recommended inventory of products. The system uses machine operation/failure information and defective product/work-in-process tracking information to support intelligent scheduling. Furthermore, a genetic algorithm model is applied to handle the complexity of heuristic rules and machine/quality constraints in this process. As a result of the development, the recommended inventory compliance rate is improved by scheduling the 30-day production plan for 15 main products.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.907-913
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• 2009

Pipeline construction is a highly repetitive and resource-intensive process that is exposed to various constraints and uncertainties in the working environment. Effective look-ahead scheduling based on the most recent project performance data can greatly improve project execution and control. This study enhances the traditional linear scheduling method with stochastic simulation to incorporate activity performance uncertainty in look-ahead scheduling. To facilitate the use of this stochastic method, a computer program, Stochastic Linear Scheduling Method (SLSM), was designed and implemented. Accurate look-ahead scheduling can help schedulers to better anticipate problem areas and formulate new plans to improve overall project performance.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1468-1473
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• 2009

Efficient communication of construction information has been critical for successful project performance. Building Information Modeling (BIM) has appeared as a tool for efficient communication. Through 3D CAD objects, it is possible to check interception and collisions of each object in advance. In addition, 4D simulation based on 3D objects integrated with time information makes it realize to go over scheduling and to perceive potential errors in scheduling. However, current scheduling simulation is still at a stage of animation due to manual integration of 3D objects and scheduling data. Accordingly, this study aims to develop an integrated model of 3D CAD objects that automatically creates scheduling information.