• IE interfaces
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• v.11 no.3
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• pp.103-114
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• 1998

This paper suggests a computer software system which generates standard times for assembly products. The system called "computer aided logical system for standard times(CALS4ST)" incorporates a modified bill of materials, BOM4ST(BOM for standard time) to deal with auxiliary operations which are not directly related to parts and assemblies listed in the standard BOM. Typical examples of the operations include inspection, adjustment, and repairing works to be done before or after assembly operations. Once standard time data bases for both the part assembly operations and the auxiliary operations are set up, the system relates the BOM4ST to the standard time data bases so as to calculate the standard time for a assembly part concerned. According to the structure of parts and auxiliary operations in the BOM4ST, their standard times stored in the data bases are to be sequentially added up considering the specified assembly-operation characteristics. To illustrate the feasibility of the system, the case study of L company is provided.

• Journal of the Korea Safety Management & Science
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• v.2 no.1
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• pp.77-87
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• 2000

BOM has been widely used to manufacturing, product design and scheduling. There are several bug differences between Manufacturing BOM and Engineering BOM, which cause a lot of problems. A study to integrate both manufacturing BOM and Engineering BOM is researching to solve those problems. Therefore, this research presents a extended Engineering BOM concepts considering assembly sequence model.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.04a
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• pp.175-178
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• 2000

BOM has been widely used to manufacturing, product design and scheduling. There are several bug differences between Manufacturing BOM and Engineering BOM, which cause a lot of problems. A study to integrate both manufacturing BOM and Engineering BOM is researching to solve those problems. This thesis presents a extended Engineering BOM concepts considering assembly sequence model.

• Korean Journal of Computational Design and Engineering
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• v.2 no.2
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• pp.93-102
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• 1997

Most design changes are due to interferences and fit-up as parts are assembled if such a large product as an automobile or an aircraft is developed by many concurrent engineers. In this part (1) of the thesis, the assembly-centric modeling methodology with CAD systems is proposed in order to reduce the design changes. Unlike part-centric modeling method, a part is modeled with its own coordinate system which is used in downstream process as machining and measuring. The part coordinates initially have the same orientation as its assembly which is predefined in BOM (Bill of Material). Then, the corrdinates origin of the part is moved to its location to be assembled from that of its assembly coordinate system. To implement this methodology, the position data of the part w.r.t. its assembly are stored in a database to build the same hierarchical assembling structure as BOM structure. This modeling approach has the advantage of reflecting asembling sequence, because the process of positioning parts is similar to that of real assembling. And with the method, a designer can easily adjust all of the part positions of an assembly to resolve interferences if he modifies just the coordinates origin of the assembly, which results in moving included parts and assemblies together.

• Journal of Korean Institute of Industrial Engineers
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• v.29 no.1
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• pp.49-64
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• 2003

Although assembly sequence planning is an essential task in assembly process planning, it is known as one of the most difficult and time consuming jobs because its complexity is increased geometrically when the number of parts in an assembly is increased. The purpose of this study is to develop a more efficient algorithm for generating assembly sequences automatically. By considering subassemblies, a new heuristic method generates a preferred parallel assembly sequence that can be used in robotic assembly systems. A parallel assembly sequence concept provides a new representation scheme for an assembly in which the assembly sequence precedence information is not required. After an user inputs both the directional mating relation information and the mating condition information, an assembly product is divided into subgroups if the product has cut-vertices. Then, a virtual disassembly process is executed to generate alternate parallel assembly sequences with intermediate assembly stability. Through searching parts relations in the virtual disassembly process, stable subassemblies are extracted from translation-free parts along disassembling directions and this extraction continues until no more subassemblies are existed. Also, the arithmetic mean parallelism formula as a preference criterion is adapted to select the best parallel assembly sequence among others. Finally a preferred parallel assembly sequence is converted to an assembly BOM structure. The results from this study can be utilized for developing CAAPP(Computer-Aided Assembly Process Planning) systems as an efficient assembly sequence planning algorithm.

• Korean Journal of Computational Design and Engineering
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• v.17 no.3
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• pp.216-223
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• 2012

Bill of material (BOM), which structurally represents the relation among parts constructing a product, is usually created when enterprises start to develop a new product. And it is shown as various types of BOM according to business needs and usage such as eBOM (engineering BOM), gBOM (green BOM), mBOM (manufacturing BOM), pBOM (process BOM), etc. eBOM, generally called BOM and created in the design stage of the new product, includes the drawing information of parts in the view of product function. eBOM is extended to gBOM adding the material information of parts to cope with international regulations for environment. eBOM is transformed to mBOM, which includes manufacturing sequence of parts and adds some parts required to fabricate parts and to assemble the product. mBOM is also extended to pBOM adding the process information of each part and additional assembly processes. This study introduces the concept of multi-BOM covering eBOM, gBOM, mBOM and pBOM, and proposes an advanced way to manage product data using multi-BOM system. The multi-BOM system proposed is to manage their relations using transformation function of BOM and master information of all BOMs.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.1999-2004
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• 2008

This study is about to constructing BOM for managing and integrating information, which is drawing, technical data, attribution, design, ordering, cost, weight, process, service, etc. based on train's system, elements, substructure, assembly, components, parts during whole train's lifetime of the next generation. The BOM is the mostly basic structure information as hierarchical data what are parts consisted specific products. The BOM was utilized as essential elements for collectively managing through informing all of the business activity from ordering to supplying. The BOM in railroad is consist of two parts. One is Engineering BOM for design, the other is Production BOM for production, which are utilized in development calculating the quantity of materials. Also the Maintenance BOM is applied to suppling parts and managing malfunction in railroad corporation like the Seoul Metro. There are many kind of BOMs, because of the special character for each step. Therefore We have need to develop BOM which is able to integrate drawing, technical data for helping good circulation between RAMS applied maintenance using database and helpful know-how for development and production. Also the BOM of the next generation must be consisted regard to whole life-cycle.

• IE interfaces
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• v.7 no.1
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• pp.67-74
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• 1994

In this study, we propose an integrated CAD(Computer Aided Design) library database in a heterogeneous commercial ECAD(Electronic CAD) environment. To effectively solve engineering problems focused on BOM data extraction we use a software system called schematic capture and company-wide standard electronic part information loaded on different commercial ECADs. We unify many commercial ECADs into one schematic capture and a variety of PCB(Printed Circuit Board) design tools. For this purpose we develope a model for linking CAD symbol library with company-wide standard part information. We also develope a schematic design data conversion scheme and show how to extract PBA level BOM data using our customized schematic capture. This system is being operated in an X-Window based engineering work station and commercial RDBMS base.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.24 no.69
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• pp.13-22
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• 2001

The efficient quality assurance system to prevent mixed assembly in introduced in this paper, It supports JIT(Just-In-Time) based Kanban and demand pull system. A new system is designed for the synchronized production and quality assurance using barcode and production kanban card, And the performance improvement method for the stable and fast response of the proposed system is suggested in this paper also. As the result of the proposed system, we improved production status visibility and quality traceability.

• Journal of the Society of Naval Architects of Korea
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• v.38 no.2
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• pp.79-86
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• 2001

This study shows an attempt to generate an assembly sequence and its model for a ship block assembly using the graph theory and graph algorithms. To generate the ship block assembly, we propose four levels of the ship block assembly model such as "geometry mode1", "relational model", "sequential mode1", and "hierarchical model". To obtain the relational model, we used surface and surface intersection algorithm. The sequential model that represents a possible assembly sequence is made by using several graph algorithms from the relational model. The hierarchical model will be constructed from the sequential model in order to represent the block assembly tree and so forth. The purpose of the hierarchical model is to define an assembly tree and to generate the Bill Of Material(BOM). Lastly, the validity of the method proposed in this study is examined with application to ship block assembly models of a single type and double type according to four models mentioned above.