• Journal of the Korean Society for Precision Engineering
• /
• v.14 no.10
• /
• pp.75-84
• /
• 1997

This paper describes the development of an integrating method for process planning and scheduling activities for block assembly in shipbuilding. A block is composed of several steel plates and steel sections with the predetermined shapes according to the ship design. The parts which constitute the block are manufac- tured by cutting and/or bending operations, which are termed as machining operation in this paper. The machining operation is the first process for block assembly which influences the remaining block assembly processes. Thus process planning and scheduling for machining operation to manufacture parts for block are very important to meet the assembly schedule in the shipyard. An integrating method for process plan- ning and scheduling is developed by introducing the concept of distributed process planning and scheduling composed of initial planning, alternative planning and final planning stages. In initial planning stage, nesting parts information and machining emthods are generated for each steel plate. In alternative plan- ning stage, machine groups are selected and workcenter dispatching information is generated. In final planning stage, cutting sequences are determined. The integrated system is tested by case study. The result shows that the integrated system is more efficient than existing manual planning system.

• Journal of Korean Institute of Industrial Engineers
• /
• v.24 no.4
• /
• pp.559-569
• /
• 1998

Cellular manufacturing system (CMS) has been recognized as an alternative to improve manufacturing productivity in conventional batch-type manufacturing systems through reducing set-up times, work-in-process inventories and throughput times by means of group technology. Most of the studies on the design of CMS assumed that each part has a unique process plan, and that its demand is known as a deterministic value despite of the probabilistic nature of the real world problems. This study suggests an approach for designing CMS, considering both alternative process plans and uncertain demand. A mathematical model is presented to show how to minimize the expected amortized and operating costs satisfying these two relaxations. Four heuristic algorithms are developed based on tabu search which is well suited for getting an optimal or near-optimal solution. Example problems are carried out to illustrate the heuristic algorithms and each of them is compared with the deterministic counterpart.

• Journal of the Korea Construction Safety Engineering Association
• /
• s.52
• /
• pp.58-66
• /
• 2011

This study presents an algorithm to select the best alternative plane among various bridge superstructure types (Steel box girder, Rational girder, PSC-I girder) using Value Engineering (VE). Economical efficiency, landscape, constructability, maintenance, stability, function of bridge superstructure were taken into consideration in the designing of bridge. Economical efficiency was evaluated for each alternative plan with optimal design considering Life Cycle Cost (LCC), Repair and rehabilitation histories and some factors were set to get reasonable results. In the application of Analytic Hierarchy Process (AHP), consistency of Pairwise Comparisons Matrix was evaluated and the best plan was determined.

• Journal of Korean Institute of Industrial Engineers
• /
• v.36 no.1
• /
• pp.42-51
• /
• 2010

The semiconductor industry is highly capital and technology intensive. Technology advancement on circuit design and process improvement requires chip makers continuously to invest a new fabrication facility that costs more than 3 billion US dollars. Especially major semiconductor companies recently started to discuss 450mm fabrication substituting existing 300mm fabrication of which facilities were initiated to build in 1998. If the plan is consolidated, the yield of 450mm facility would be more than doubled compared to existing 300mm facility. In steps of this important investment, facility layout has been acknowledged as one of the most important factors to be competitive in the market. This research proposes a new concept of semiconductor facility layout using hexagonal floor plan and its compatible material flow pattern. The main objective of this proposal is to improve the productivity of the unified layout that has been popularly used to build existing facilities. In this research, practical characteristics of the semiconductor fabrication are taken into account to develop a new layout alternative based on the analysis of Chung and Tanchoco (2009). The performance of the proposed layout alternative is analyzed using computer simulation and the results show that the new layout alternative outperforms the existing layout alternative, unified layout. However, a few questions on space efficiency to the new alternative were raised in communication with industry practitioners. These questions are left for a future study.

• Journal of the Korean Institute of Educational Facilities
• /
• v.18 no.1
• /
• pp.3-10
• /
• 2011

Recently, an active relation between the University and city has become an issue of increasing importance in the field of campus planning. Campus master plan is known as long range development plan, and is not simply an abstract drawing work but definite scaling work procedure. The purpose of this paper is to examine the planning process and relation between university and the region through master plan of master plan of D University and K University which located in Seoul city. From the research which sees master plan of D universities which are presented in existing an instance and K universities master plan did the service blueprint with base and investigated. And both university currently analyzed the situation which is being placed and grasps a problem point, presented that alternative with what kind of method.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.39 no.3
• /
• pp.83-89
• /
• 2016

The group formation problem of the machine and part is a critical issue in the planning stage of cellular manufacturing systems. The machine-part grouping with alternative process plans means to form machine-part groupings in which a part may be processed not only by a specific process but by many alternative processes. For this problem, this study presents an algorithm based on self organizing neural networks, so called SOM (Self Organizing feature Map). The SOM, a special type of neural networks is an intelligent tool for grouping machines and parts in group formation problem of the machine and part. SOM can learn from complex, multi-dimensional data and transform them into visually decipherable clusters. In the proposed algorithm, output layer in SOM network had been set as one-dimensional structure and the number of output node has been set sufficiently large in order to spread out the input vectors in the order of similarity. In the first stage of the proposed algorithm, SOM has been applied twice to form an initial machine-process group. In the second stage, grouping efficacy is considered to transform the initial machine-process group into a final machine-process group and a final machine-part group. The proposed algorithm was tested on well-known machine-part grouping problems with alternative process plans. The results of this computational study demonstrate the superiority of the proposed algorithm. The proposed algorithm can be easily applied to the group formation problem compared to other meta-heuristic based algorithms. In addition, it can be used to solve large-scale group formation problems.

• The Journal of Information Systems
• /
• v.17 no.4
• /
• pp.301-319
• /
• 2008

The display market has been replaced by the FPD (Flat Panel Display) from the CRT (Cathode-Ray Tube) since the late 1990s. In the FPD production line, the most equipment has high price. Thus, when the equipment has multi-function, the repetitive process is arranged for the equipment. However, such disposition of equipment results in more complicated process flow owing to repetitive operations. This reduces the production capacity and increases lead-time in turn. In this paper, we develop an AutoMod simulation system that derives to information about the quantity, production lead-time, utilities of facilities, and occupation rates of racks. In this simulation system, we consider the situation where the equipment might be broken and suspended randomly. For the developed system, we first evaluate a production plan with current layout and then, propose a revised alternative plan. Using the same simulation scheme, we investigate comparing the production quantity and lead-time with the two plans. In addition, for a proposed alternative, we try to forecast the most adequate rule between the two job dispatching rules which are FOR (Fewest Operation Remaining) and FCFS (First Come First Serve) through simulation.

• Korean Journal of Construction Engineering and Management
• /
• v.2 no.4 s.8
• /
• pp.48-61
• /
• 2001

This study aims at improving work reliability. It proposes a way to overcome the limitations of current scheduling methods by providing a new framework, CPAM(Construction Process Analysis Model) based on the lean principles. It suggests methods which improve work reliability and production effectiveness with variability control methods. Also it suggests methods which reduce inventories of materials and equipment and WIP(Work In Process) using two techniques; Lookahead Schedule and Weekly Work Plan. The contribution of this research also includes that it assumes planning as a process of reducing uncertainty and maximizing throughput, counter-posing plan reliability to resource redundancy as alternative strategies for managing in conditions of uncertain work flow.

• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.1105-1114
• /
• 2007

Recently the urban railroad which is under plan and construction in domestic is under consideration Light Rail Transit mostly with the alternative against excess of working expenses of Midium Rail Transit(subway), inefficient transportation problem etc. It come to a conclusion that the application of the light rail transit is proper from reserve feasibility study and approval process of Master plan in Daegu urban railroad Line No.3 Based on hereupon, carried out the detail investigation for optimum system selection which suitable for Daegu urban circumstance in process of master plan can satisfy the working expenses decided in national expenditure support project.

• Journal of the Korean Institute of Educational Facilities
• /
• v.12 no.6
• /
• pp.56-67
• /
• 2005

The purpose of this study is to give the detailed evaluation index which is considered by reconstruction and repair for the school facilities on the ground of the efficiency evaluation result in each plan through analyzing the school facilities to every case classified into the evaluation index such as the school site plan, the site plan, the floor plan. On this study through the detailed evaluation index each case to the school facilities is to get the result of the efficiency evaluation. Through analysing the result, to make an alternative plan of the school facilities which are fit in both the new educational process and the educational state is to give it as a guide.