• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.19 no.39
• /
• pp.255-264
• /
• 1996

This Paper presents a heuristic algorithm for machine-part group formation considering part production information (Production volume, roution sequence, unit operation time, facility size) in cellular manufacturing logistics system. In general, factory space is restricted within limited size when cells are located. A twofold heuristic algorithm is developed for considering factory space restrictions of located cells. The first phase is a aggregation procedure to minimize inter cell movement for satisfactoring space restriction. The second phase is a rearrangement procedure to maximize line balancing efficiency between machines within the cell and non assigned machine during first phase. Numerical example is presented to verify the efficiency of proposed algorithm.

• Design & Manufacturing
• /
• v.17 no.1
• /
• pp.64-69
• /
• 2023

This paper explores the impact of gate shape changes on the size and density of foamed cells in microcellular foam injection molding. Five different gate shapes were examined while varying the amount of nitrogen gas(N2) injected for foaming. Analysis of the results showed that while average values did not change significantly, deviation values decreased by approximately 65% for cell size and 56% for density when 3.5wt% of nitrogen gas was injected in the film gate. Further analysis was conducted to verify this phenomenon, revealing that the contact area between the gate and product had the greatest impact. Our findings indicate that to ensure uniform generation of foamed cells in microcellular foaming product design, a gate with a wide contact area should be secured.

• Progress in Superconductivity and Cryogenics
• /
• v.10 no.2
• /
• pp.27-29
• /
• 2008

Superconducting RF cavities are being considered for accelerating a proton beam at 700 MHz in the linac of the Proton Engineering Frontier Project (PEFP) and its post-project. Dumbbell fabrication is a mid-process for manufacturing an elliptical superconducting RF cavity. During the dumbbell fabrication, control of the dumbbell length and the $TM010\;{\pi}$ mode frequencies is necessary to build up a desired cavity. A new formula with a perturbation measurement method is used to measure and calculate the frequencies of the individual half-cells of a PEFP low-beta dumbbell, and to tune the frequency and length of the half-cells. In this article, the tuning method and results of the PEFP low-beta dumbbells have been presented.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.19 no.40
• /
• pp.157-167
• /
• 1996

공구계획 문제는 FMC의 설계 단계에서 고려되어야만 하는 중요한 요소 중의 하나이다. 본 연구에서는 FMC에서 흔히 사용되는 머쉬닝센터를 대상으로 공구이동정책을 사용할 때 공구의 이동을 최소화할 수 있는 공구계획에 그 목적을 두고 있다. 공구매거진의 제한된 공구수용능력 과 머쉬닝센터 간의 공구이동량을 최소화하여 작업의 공구대기시간을 감소시킴으로써 기계의 이용율을 높이고 생산량을 증대시킬 수 있다. 총공구 수가 주어진 조건하에서 공구의 이동량을 최소화하면서 각 공구의 숫자를 결정하는 수학적 모델을 개발하여 효율적인 해법을 제시하였으며, 실험결과 짧은 시간에 우수한 해를 제공하는 것이 입증되었다.

• Journal of Institute of Control, Robotics and Systems
• /
• v.6 no.6
• /
• pp.478-485
• /
• 2000

A discrete event systems (DES) is a physical system that is discrete in time and state space, asynchronous (event rather than clock-driven), and in some sense generative(or nondeterministic). This paper presents the design of fifteen modular supervisors to control an experimental CIM testbed. These supervisors are nonblocking, controllable and nonconflicting. After verification of the supervisors by simulation, the supervisors for AGV system have been implemented to demonstrate their efficacy.

• Proceedings of the PSK Conference
• /
• 2003.04a
• /
• pp.118.2-119
• /
• 2003

This study was undertaken to assess overall effects of bisphenol A, a monomer widely used in manufacturing polycarbonate plastics or epoxy resin, exposure on immune system of mice. For in vitro evaluation, serial concentration of SPA was added into culture of various immune cells from normal female ICR mice, and for in vivo or ex vivo assessment, mice were orally exposed to BPA dissolved in olive oil as doses of 500, 1000, 2000 mg/g b.w. for acute expose or 100, 500, 1000 mg/kg/day b.w. 5days a week for subacute exposure. (omitted)

• Proceedings of the PSK Conference
• /
• 2001.04a
• /
• pp.125.2-126
• /
• 2001

• 제어로봇시스템학회:학술대회논문집
• /
• 1992.10a
• /
• pp.370-375
• /
• 1992

This paper deals with the scheduling and simulation for FMC(Flexible Manufacturing Cells). In order to achieve CIM, there is a critical need to link factory level and machine level. The primary functions performed by this link for all jobs issued to the shop floor and cell include short-term scheduling and dynamic operational scheduling. Here, hierarchical control structure is introduced to define these functions. And Intelligent scheduling through expert module is adopted for efficiency of FMC operation. Computer simulation reveals that expert scheduling method is better than heuristics in various performance index.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.19 no.37
• /
• pp.1-7
• /
• 1996

The grouping of parts into families and machines into cells poses an important problem for the improvement of productivity and quality in the design and planning of the flexible manufacturing system(FMS). This paper proposes a new algorithm of forming machine-part groups in case of the bottleneck machine problem and shows the numerical example. This algorithm could be applied to the large scale machine-part grouping problem.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.18 no.34
• /
• pp.91-97
• /
• 1995

This paper presents a possible application of artificial neural network in CM system design. CM systems can be designed based on product lines, part characteristics or part routines. GT(Group Technology) which uses part characteristics to design cells is widely applied, however, the identification of the part-machine families is the fundamental problem in the design process. A heuristic procedure using SOFM which requires only part-machine incidence matrix is proposed in this research. Comparison studies on ZODIAC and ROC with SOFM model are done and the results are discussed and summarized in this paper.