• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.403-413
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• 1996

Two-phase self-organizing neuro-modeling (SONM). the global SONM and local SONM, is designed for tracking non-stationary manufacturing processes. Radial basis function (RBF) neural network is employed, and self-tuning estimator is also developed for the determination of RBF network parameters on-line. A pattern recognition approach is presented for identifying a correct RBF neural network, which is used for identifying current manufacturing processes. Experimental results showed that the proposed approach is suitable for tracking non-stationary processes.

• 대한산업공학회지
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• 제23권2호
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• pp.343-357
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• 1997

This paper proposes a new AGV dispatching algorithm which is suitable for heterarchical manufacturing control structure. It is developed on the basis of bidding concept utilizing the information of work-in-process in incoming and outgoing buffers of workstation, and travel time of AGV. Since the bidding functions are functions of two parameters, sensitivity test is performed to find their appropriate values. The performance of the algorithm is compared with those of well-known existing rules in terms of system throughput through simulation on a hypothetical job shop type manufacturing system.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 1999년도 추계학술대회 논문집
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• pp.224-228
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• 1999

When we construct a manufacturing plant, optimal design is very important. This paper is to simulate an engine manufacturing flow line for commercial vehicle. The parameters we consider in simulation include facility downtime, tool change time, buffer size between consecutive stations, and time to repair the facility. We use AutoMod to compare the alternatives. The objective is to minimize the total cost. Simulation results provide significant cost saving by improving the current design and policy.

• 소성∙가공
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• 제33권1호
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• pp.36-42
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• 2024

Additive manufacturing with 3XX austenitic stainless steels has been widely investigated during a decade due to its high strength, good corrosion resistance, and fair weldability. However, in recently, Ni price drastically increased due to the high demand of secondary battery for electric mobilities. Thus, it is essential to substitute the Ni with Mn for reducing stainless steels price. Meanwhile, the chemical composition changes in stainless steels not only affect to its properties but also change the optimal processing parameters during additive manufacturing. Therefore, it is necessary to optimize the processing parameters of each alloy for obtaining high-quality product using additive manufacturing. After processing optimization, mechanical properties and microstructure of the laser-powder bed fusion processed Fe-15Cr-7Ni-3Mn alloy were investigated in both room (298 K) and cryogenic (77 K) temperatures. Since the temperature reduction affects to the deformation mechanism transition, multi-scale microstructural characterization technique was conducted to reveal the deformation mechanism of each sample.

• 소성∙가공
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• 제12권2호
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• pp.110-115
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• 2003

This paper is concerned with the compression test and forming process of flange by using virtual reality and analysis(simulation) program. This virtual manufacturing can be carried out one personal computer without any expensive devices for experiment. The virtual manufacturing composed of three modules such as the imput, calculation and the output modules on internet. Internet user can give the material's property and process parameters to the sever computer at the input module. On the calculation module, a simulator computes the virtual manufacturing process by analysis program and stores the data as a file. The output module is the program in which internet user can confirm virtual manufacturing results by showing tables, graphs, and 3D animation. This programs is designed by an internet language such as HTML, CGI, VRML and JAVA ,while analysis programs use the finite increasing, the virtual manufacturing technique will substitute many real experiments in the future.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.555-560
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• 2002

This paper addresses the methodologies for manufacturing systems design. While a number of design methods are used in product or part design, methods for manufacturing systems design are rarely known. Two approaches, simulation and axiomatic design theory, are discussed with respective case examples. The usual purpose of using simulation is to identify the bottleneck of a manufacturing system or to evaluate its performance with the aim of configuring the manufacturing system. The simulation typically proceeds in steps such as problem definition, model building, numerical experimentation, analysis and evaluation. The axiomatic design method transforms customer attributes into functional requirements and repeats mapping processes between functional domain and physical one until a satisfactory level of refinement of the functional requirements and the design parameters is reached. Possible design alternatives are evaluated by applying the independence axiom as well as the information axiom.

• 한국기계가공학회지
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• 제6권4호
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• pp.92-97
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• 2007

A temporary structure is a framework of metal poles and planks, used as a working platform from which building repairs or construction can be carried out safety. The manufacturing process of the existing model consumes a many hour. So, it is modified manufacturing process. In this study, it is attempted to find out the shape of modified working platform considering manufacturing process and using Taguchi method, and it reduces production process. The design parameters are defined to discribe shape of model. As a result of the shape design, maximum Von-Mises stress and displacement considering a safety factor were satisfied with CTEA (Construction Temporary Equipment Association of Korea) standard.

• Journal of Information Processing Systems
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• 제16권6호
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• pp.1271-1280
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• 2020

The yield and quality of a micromanufacturing process are important management factors. In real-world situations, it is difficult to achieve a high yield from a manufacturing process because the products are produced through multiple nanoscale manufacturing processes. Therefore, it is necessary to identify the processes and equipment that lead to low yields. This paper proposes an analytical method to identify the processes and equipment that cause a defect in the plastic ball grid array (PBGA) during the manufacturing process using logistic regression and stepwise variable selection. The proposed method was tested with the lot trace records of a real work site. The records included the sequence of equipment that the lot had passed through and the number of faults of each type in the lot. We demonstrated that the test results reflect the real situation in a PBGA manufacturing process, and the major equipment parameters were then controlled to confirm the improvement in yield; the yield improved by approximately 20%.

• Industrial Engineering and Management Systems
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• 제4권2호
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• pp.184-191
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• 2005

In this article we study the feasibility of the Ant Colony Optimisation (ACO) algorithm for finding optimal Kanban allocations in Kanban systems represented by Stochastic Petri Net (SPN) models. Like other optimisation algorithms inspired by nature, such as Simulated Annealing/Genetic Algorithms, the ACO algorithm contains a large number of adjustable parameters. Thus we study the influence of the parameters on performance of ACO on the Kanban allocation problem, and identify the most important parameters.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1998년도 춘계학술대회 논문집
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• pp.35-39
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• 1998

Determination of effective EDM parameters is significant to increase productivity. However, With the complexity of EDM phenomena, a universal selection method of EDM parameters has not been established yet. Moreover, No attempt has been tried before to suggest a logical method in determining essential machining parameters for effective electrical discharge machining. Peak current, one of the most significant factors in EDM, is proportional to EDM area. This paper presents a method that can be Z-map modeling from CMM data, and calculate EDM area using Z-map.