• Title/Summary/Keyword: Re-Manufacturing

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- Development of an Algorithm for a Re-entrant Safety Parallel Machine Problem Using Roll out Algorithm - (Roll out 알고리듬을 이용한 반복 작업을 하는 안전병렬기계 알고리듬 개발)

  • Baek Jong Kwan;Kim Hyung Jun
    • Journal of the Korea Safety Management & Science
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    • v.6 no.4
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    • pp.155-170
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    • 2004
  • Among the semiconductor If-chips, unlike memory chips, a majority of Application Specific IC(ASIC) products are produced by customer orders, and meeting the customer specified due date is a critical issue for the case. However, to the one who understands the nature of semiconductor manufacturing, it does not take much effort to realize the difficulty of meeting the given specific production due dates. Due to its multi-layered feature of products, to be completed, a semiconductor product(called device) enters into the fabrication manufacturing process(FAB) repeatedly as many times as the number of the product specified layers, and fabrication processes of individual layers are composed with similar but not identical unit processes. The unit process called photo-lithography is the only process where every layer must pass through. This re-entrant feature of FAB makes predicting and planning of due date of an ordered batch of devices difficult. Parallel machines problem in the photo process, which is bottleneck process, is solved with restricted roll out algorithm. Roll out algorithm is a method of solving the problem by embedding it within a dynamic programming framework. Restricted roll out algorithm Is roll out algorithm that restricted alternative states to decrease the solving time and improve the result. Results of simulation test in condition as same as real FAB facilities show the effectiveness of the developed algorithm.

Application of Axiomatic Design Theory in Manufacturing System Design (공리적 설계 기법을 이용한 생산시스템 설계 지원 방안에 대한 고찰)

  • 백태진;강무진
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.82-86
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    • 2004
  • To cope with the challenge from global market characterized by frequent changes in requirements, manufacturing enterprise should be able to promptly adjust its manufacturing system accordingly. Therefore, it is important to provide manufacturing system designer with an appropriate methodology to (re-)design a manufacturing system subject to requirements change. Axiomatic design theory focuses design activity mainly on functional consideration rather than physical, and has been known as effective especially in the conceptual design phase. This paper introduces an approach to apply the axiomatic design principle to manufacturing system design. It is shown that a new design solution can be reached quickly by finding design parameters for the added or revised functional requirements and thus achieving a set of functional requirements as well as design parameters that satisfy the independence axiom. Some illustrative examples are also given.

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Six Sigma and Lean Manufacturing - A Merger for Worldclass Performance, but is it Really Talking Place?

  • Kroslid, Dag
    • International Journal of Quality Innovation
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    • v.2 no.1
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    • pp.87-105
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    • 2001
  • More than a decade after their development and first wave of deployment, Six Sigma and Lean Manufacturing have recently returned on the corporate agendas of a larger number of corporations across industries and supply chains. In the wake of their re-surge, this commentary addresses the evolution, context, content and deployment patterns of the two distinct management concepts. It also analyses claims in the business press that a merger is taking place between Six Sigma and Lean Manufacturing. Here, it is found that there is not enough evidence to broadly support such claims, and it is only concluded that there is some evidence of an early tend towards a merger and that a possible merger would have many synergies and advantages. Finally, an example from a Scandinavian manufacturing company is provided that explains how Six Sigma and Lean Manufacturing can be used in a beneficial way for companies to reach world-class performance.

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Usage of Dynamic Vibration Absorbers for a Beam Subjected to Moving Forces and for a System Mounted on a Moving Base (이동하중을 받는 보와 가동 기초 위에 설치된 계에의 동흡진기의 이용)

  • Lee, Gun-Myung;Byun, Jai-Hyun
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.14 no.6
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    • pp.27-34
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    • 2015
  • Dynamic vibration absorbers are widely used in machinery, buildings, and structures, including bridges. Two cases of their usage are considered in this paper. One is a simply supported beam subjected to either a moving force or a sequence of moving forces, which simulates a train-bridge interaction problem. The other is a case where a primary system is mounted on a base that is not grounded and is excited by an external force. The conditions that the dynamic vibration absorbers must meet in these cases are found and compared to those for usual cases where bases of primary systems are grounded.

Laser Cutting of Flexible Printed Circuit Board in Liquid (연성인쇄회로기판의 액중 레이저 절단)

  • Kim, Teakgu;Kim, Joohan
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.22 no.1
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    • pp.56-62
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    • 2013
  • The laser cutting process which is flexible and rapid usually provides a better result in cutting of flexible printed circuit boards (FPCB). However, circuit-short by the re-deposition of debris from laser ablation or its heat affect zone (HAZ) on the cutting surfaces can be a problem. A laser cutting process of FPCB in the presence of liquid can minimize these negative effects. The temperature distribution of copper and polymer parts of FPCB was analyzed with numerical simulation and the experimental results were presented to evaluate this process. Generally, laser cutting under liquid has advantages of less re-deposition of carbides and less HAZ on the cutting edges. However, bubble generation and laser beam control through the liquid media should be considered carefully to obtain a successful result.

Study of the air liquefaction system using the LNG cold energy (LNG 냉열을 이용한 공기 액화의 특성 연구)

  • Park, Dong-Hoon;Yun, Sang-Kook
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2006.06a
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    • pp.233-234
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    • 2006
  • LNG is extremely cold, $-160^{\circ}C$ in its liquid state. When it vaporizes, returning to its natural state (re-vaporization), it cools its surroundings. This is cold energy. The manufacturing of liquid air is the first processes developed as the most effective utilization of LNG cold. In this paper, adopting the LNG cold process for manufacturing liquid air was developed and analysed. The result showed that as the higher air pressure and adapting nitrogen precooling, liquefaction rate and cumulative mass was increased.

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A Study on Processing and Performance of a 600dpi Master F-theta Lens (600dpi 마스터 에프세타 렌즈 가공 및 성능에 관한 연구)

  • Park, Yong-Woo;Moon, Seong-Min;Lyu, Sung-Ki
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.19 no.5
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    • pp.1-7
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    • 2020
  • This study examines the processing and performance of an f-theta lens, one of the main components used in laser printer and laser scanning systems. To design an f-theta lens, the optical path of the components of the laser scanning unit f-theta lens, cylinder lens, and collimator lens must be identified. The goal after machining the master f-theta lens is to understand the optical properties, root mean square, and peak to valley.

A study on the selection methodology of materials by design process in manufacturing process (제조공정에서 디자인 프로세스에 의한 소재선정 방법론 연구)

  • Song, Sung-il;Kang, Seung-min
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.29 no.1
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    • pp.39-44
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    • 2019
  • This study renewed the 'RE_Double Diamond' design process on the importance that material selection should reflect the needs of the consumer as much as possible in product development. In addition, the provider-centered secondary stakeholder map process among existing double-diamond methodologies has been applied, and the selection of materials through communication between designers and engineers, including the construction of information focused on visualization.

A Study on the Design of a Gear Transmission Error Test Rig (기어 전달오차 측정 장비의 설계에 관한 연구)

  • Zhang, Qi;Zhang, Jing;Yan, Hou-Ling;Zhu, Qing-Wang;Xu, Zhe-zhu;Lyu, Sung-Ki
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.15 no.1
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    • pp.14-19
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    • 2016
  • Transmission error (TE) is the most important cause of gear noise and vibration because TEs affect the changes of the force and the speed of gears. TE is usually expressed as an angular deviation, or a linear deviation measured at the pitch point and calculated at successive positions of the pinion as it goes through the meshing cycle. Accurate measurement of TE for gear transmission will provide a reasonable basis for gear design, manufacturing processes and quality control. Therefore, in order to study the accuracy of the gear transmission, stability, TE, vibration and noise after gear micro-geometry modification, a gear transmission test rig is proposed in this paper, which is based on the existing technical conditions, by using reasonable testing methods, hardware and a signal processing method. All of the details and the experience can be taken into consideration in the next upgraded test rig.

Rapid Manufacturing of 3D Prototype from 3D scan data using VLM-ST (단속형 가변적층쾌속조형공정을 이용한 3차원 스캔데이터로부터 3차원 시작품의 쾌속 제작)

  • 이상호;안동규;김효찬;양동열;박두섭;채희창
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.536-539
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    • 2002
  • The reverse engineering (RE) technology can quickly generate 3D point cloud data of an object by capturing the surface of a model using a 3D scanner. In the rapid prototyping (RP) technology, prototypes are rapidly produced from 3D CAD models in a layer-by-layer additive basis. In this paper, a physical human head shape is duplicated using a new RP process, the Transfer-type Variable Lamination Manufacturing process using expandable polystyrene foam sheet (VLM-ST), after the point cloud data of a human head shape measured from 3D SNX scanner are converted to STL file. From the duplicated human head shape, it has been shown that the VLM-ST process in connection with the 3D scanner is a fast and efficient process in that shapes with free surface, such as the human head shape, can be duplicated with ease. Considering the measurement time and the shape duplication time, the use of 3D SNX scanner and the VLM-ST process is expected to reduce the lead-time fur the development of new products in comparison with the other existing RE-RP connected manufacturing systems.

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