• Journal of Korean Society of Industrial and Systems Engineering
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• v.19 no.38
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• pp.139-146
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• 1996

In this thesis, we suggest the application of dock scheduling which is based on zero-one integer programming. A knowledge based system for dock scheduling was developed to implement this mathematical method.

• Journal of Industrial Technology
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• v.19
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• pp.91-99
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• 1999

The dock is the most important resource in shipbuilding yard. Among the shipbuilding schedules, the ship erection schedule in a dock is preferentially built. As results of it, the other schedules(machining in plants, block assembly, pre-painting, pre-rigging, painting and etc) are made. In this study, ship erection scheduling is formulated using ILOG Scheduler. This study is to develop a new problem solving method for ship erection to make an effective schedule based on Constraint Satisfaction Technique(CST).

• Korean Journal of Computational Design and Engineering
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• v.17 no.6
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• pp.409-416
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• 2012

Most of the shipbuilding scheduling researches so far have been conducted with stress on the dock plan. That is due to the fact that the dock is the least extendable resource in shipyards and its overloading is difficult to resolve. However, once the dock scheduling is completed, it is also important to make a plan that make the best use of the rest of the resources in the shipyard, so that any additional cost is minimized. This study automates block allocation process by analyzing the existing manual process that designates production bays for the blocks during the midterm planning. Also, a planning scenario validation method is suggested, where block allocation scenarios based on diagrams are edited and simulated.

• IE interfaces
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• v.14 no.3
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• pp.218-226
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• 2001

Scheduling for shipbuilding processes has many alternative solutions since it has long time horizon and handles many jobs. This requests the scheduling system to generate and search feasible alternative solutions in short period of time. Among shipbuilding schedules, the ship erection schedule in a dock is the most important since the dock is the most critical resource in shipyard. In this research, we model the erection scheduling problem for shipbuilding and develop a new problem solving method using CST(Constraint Satisfaction Technique) and ILOG Scheduler. Experimental results show that the proposed scheduling method outperforms the existing manual scheduling methods in terms of schedule performance and required time.

• IE interfaces
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• v.16 no.3
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• pp.332-343
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• 2003

This paper deals with pre-erection scheduling and erection scheduling in shipbuilding. Among shipbuilding scheduling, the ship erection scheduling in a dock is one of the most important since the dock is the most critical resource in a shipyard. However, it is more reasonable to consider pre-erection scheduling and erection scheduling as unified because they compete with the common constrained resources such as labor, crane, space, and so on. It is very hard to consider two scheduling problems simultaneously, and hence, we approach them sequentially. At first, we propose space resource leveling heuristics in pre-erection scheduling given erection date. And then, considering the manpower resource determined by pre-erection scheduling, we also propose manpower resource leveling heuristics in erection scheduling. Various experimental results with real world data show that the proposed heuristics have good performance in terms of scheduling quality and time.

• Journal of the Society of Naval Architects of Korea
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• v.44 no.1 s.151
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• pp.48-54
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• 2007

Higher productivity and less cost during the manufacturing process of ships are required to maintain international competitiveness of modern shipbuilding industries. The integrated hull/ outfitting/ painting scheduling(IHOP) process is a final point, where logistics are finally being integrated and upcoming schedules are made. Therefore, more profits are expected from IHOP by effective management. In this thesis, IHOP is proposed in order to solve how to choose block erection date with IHOP scheduling logic. The result of IHOP scheduling is highly advised to utilize fabrication, outfitting shops. A standardized operation and load of resource will eventually be applied in long-term time span point of view for this will make it easy to enable capacity planning and workforce planning. It is also expected to eliminate inefficiency in overtime work and efficiently utilize manpower in short-term.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.1
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• pp.162-174
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• 2014

Most shipbuilding scheduling research so far has focused on the load level on the dock plan. This is because the dock is the least extendable resource in shipyards, and its overloading is difficult to resolve. However, once dock scheduling is completed, making a plan that makes the best use of the rest of the resources in the shipyard to minimize any additional cost is also important. Block assignment planning is one of the midterm planning tasks; it assigns a block to the facility (factory/shop or surface plate) that will actually manufacture the block according to the block characteristics and current situation of the facility. It is one of the most heavily loaded midterm planning tasks and is carried out manually by experienced workers. In this study, a method of representing the block assignment rules using a diagram was suggested through analysis of the existing manual process. A block allocation program was developed which automated the block assignment process according to the rules represented by the diagram. The planning scenario was validated through a case study that compared the manual assignment and two automated block assignment results.

• Journal of the Korea Safety Management & Science
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• v.4 no.3
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• pp.79-93
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• 2002

Cross docking is a material handling and distribution concept in which products move directly from receiving dock to shipping dock, without being stored in a warehouse or distribution center. Depending on the facility and operating conditions or strategies employed, it is possible to generate various cross docking scenarios or models. The cross docking model, which is studied in this research, assumes there are a separate receiving dock and a separate shipping dock. It is also assumed that the products contained in a receiving truck and the products needed for a shipping truck are known in advance. Furthermore, the study is restricted to scenarios where there is only one receiving dock and only one shipping dock at the warehouse. The research objective is to find the best truck spotting sequence for both receiving and shipping trucks to minimize total operation time (i.e., the makespan) of the cross docking system.

• Journal of the Korean Operations Research and Management Science Society
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• v.30 no.4
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• pp.45-60
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• 2005

We consider a vehicle routing problem with time window and dock capacity constraints (VRPTD). In most traditional models of vehicle routing problems with time window (VRPTW), each customer must be assigned to only one vehicle route. However demand of a customer may exceed the capacity of one vehicle, hence at least two vehicles may need to visit the customer We assume that each customer has Its own dock capacity. Hence, the customer can be served by only a limited number of vehicles simultaneously. Given a depot, customers, their demands, their time windows and dock capacities, VRPTD is to get a set of feasible routes which pass the depot and some customers such that all demands of each customer are satisfied Since VRPTD is NP-hard, a meta-heuristic algorithm is developed. The algorithm consists of two Procedures : the route construction procedure and the route scheduling procedure. We tested the algorithm on a number of instances and computational results are reported.

• Proceedings of the Korea Society for Simulation Conference
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• 1998.10a
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• pp.12-16
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• 1998

The purpose of this paper is to develop a knowledge-based real-time decision support system to support decision makers for efficient berth operation of Inchon Port. In these days, the efficient berth operation has been many studied. The berth operation rules differ from port to port and the problem is highly dependent on natural, geographical and operational environment of port. In Inchon Port, the ship's entrance into port and departure from port is extremely affected by the status of dock and berth because of capacity restriction. First, we analyzed the specific characteristics of Inchon Port such as dock based on the data of 1997. And then, we construct the database of experts knowledge for berth utilization. Finally, we build the real-time decision support system for the efficient berth operation of Inchon Port to make the better berth allocation in case of not only regular scheduling but also dynamic scheduling such as delay in berth operation and exchange of ship between berths. The DSS is developed with graphic user interface(GUI) concept to help the user determining user interactive updating of the port status. Then this DSS will be provide decision maker with an efficient and fast way to berth allocation, and reduce wastes of time, space, and manpower in Inchon Port operation.