• Title/Summary/Keyword: precedence

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Balancing assembly line in an electronics company

  • 박경철;강석훈;박성수;김완희
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1993.10a
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    • pp.12-19
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    • 1993
  • In general, the line balancing problem is defined as of finding an assignment of the given jobs to the workstations under the precedence constraints given to the set of jobs. Usually, the objective is either minimizing the cycle time under the given number of workstations or minimizing the number of workstations under the given cycle time. In this paper, we present a new type of an assembly line balancing problem which occurs in an electronics company manufacturing home appliances. The main difference of the problem compared to the general line balancing problem lies in the structure of the precedence given to the set of jobs. In the problem, the set of jobs is partitioned into two disjoint subjects. One is called the set of fixed jobs and the other, the set of floating jobs. The fixed jobs should be processed in the linear order and some pair of the jobs should not be assigned to the same workstations. Whereas, to each floating job, a set of ranges is given. The range is given in terms of two fixed jobs and it means that the floating job can be processed after the first job is processed and before the second job is processed. There can be more than one range associated to a floating job. We present a procedure to find an approximate solution to the problem. The procedure consists of two major parts. One is to find the assignment of the floating jobs under the given (feasible) assignment of the fixed jobs. The problem can be viewed as a constrained bin packing problem. The other is to find the assignment of the whole jobs under the given linear precedence on the set of the floating jobs. First problem is NP-hard and we devise a heuristic procedure to the problem based on the transportation problem and matching problem. The second problem can be solved in polynomial time by the shortest path method. The algorithm works in iterative manner. One step is composed of two phases. In the first phase, we solve the constrained bin packing problem. In the second phase, the shortest path problem is solved using the phase 1 result. The result of the phase 2 is used as an input to the phase 1 problem at the next step. We test the proposed algorithm on the set of real data found in the washing machine assembly line.

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The Effects of Advanced Design Innovation Strategy on Business Performance (선행 디자인 혁신 전략이 기업 성과에 미치는 영향)

  • Kim, Yong-Wook;Song, In-Am;Hwang, Hee-Joong
    • Journal of Distribution Science
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    • v.11 no.10
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    • pp.27-36
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    • 2013
  • Purpose - This paper empirically studies the effects of advanced design innovation strategy on business performance, to investigate manufacturing industries that can develop design-driven-innovation strategies. Many researchers now recognize the importance of design in a CEO's decision-making process. To analyze these effects, this study deduces the definition of advanced design strategy by reviewing existing studies. The advanced design is a strategy that is applied to improve business performance instead of the appearance of a product for increasing its sales. In terms of business processes, the advanced design strategy is defined as the incorporation of business activities prior to the development of the product, to offer new experiences and values to users, from those designs. Research design/data/methodology - This paper establishes a model for empirical analysis. In this study, we derived factors of the characteristics of advanced design based on previous studies. We tried to investigate whether advanced design innovation strategy and entrepreneur's characteristics could have any impact on business performance. At the same time, we tried to find out the moderating effect of entrepreneurs' characteristics. The advanced design is made up of three elements: precedence, integration, and immersion of design activities. These three elements are independent variables for the model. The dependent variables are: increased rate of sales, R & D performance, and public image of the company. Specifically, this study establishes a CEO's characteristics as a moderating variable between the independent and dependent variables. Results - We proved that the level of entrepreneurs' characteristics has a moderating effect on the business performance. The findings of this study offer the following theoretical implications. The precedence of design activities positively affects the increased rate of sales by offering new experiences to users and creating new values. The integration of design activities also has a positive effect on the R&D performance. In addition, the immersion of design activities positively influences all the elements comprising business performance. The analysis of moderating variables elucidates that CEO's characteristics have a moderating role between precedence, integration, and immersion of design activities, and business performance. Conclusions - The practical implications of the study are as follows. This study contributes to the progression of advance design theories by conducting an empirical study on the advanced design concept. More importantly, the empirical study on the CEO group seeking exploratory innovation supports Verganti's "design-driven innovation" concept, according to which design can make innovation successful by offering useful values to users, as evident in the case of many innovative companies, such as Nintendo and Apple. Future studies need to investigate the reliability of practical examples, including the various activities of business. We suppose that there may be real differences between the results of this study and the applicative situation in the presence of a CEO group.

Analysis of KOSPI·Apartment Prices in Seoul·HPPCI·CLI's Correlation and Precedence (종합주가지수·서울지역아파트가격·전국주택매매가격지수·경기선행지수의 상관관계와 선행성 분석)

  • Choi, Jeong-Il;Lee, Ok-Dong
    • Journal of Digital Convergence
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    • v.12 no.5
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    • pp.89-99
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    • 2014
  • Correlation of KOSPI from stock market and Apartment Prices in Seoul HPPCI from real estate market has been found from this research. Furthermore, from the comparison of those indicators' flows, certain precedence was found as well. The purpose of this research is to analyze correlation and precedence among KOSPI, Apartment price in Seoul, HPPCI and CLI. As for predicting KOSPI of stock market and real estate market, it is necessary to find out preceding indices and analyzing their progresses first. For 27 years from the January 1987 to December 2013, KOSPI has been grown by 687%, while CLI showed 443%, Apartment of Seoul showed 391%, HPPCI showed 263% of growth rate in order. As the result of correlation analysis among Apartment of Seoul, CLI, KOSPI and HPPCI, KOSPI and HPPCI showed high correlation coefficient of 0.877, and Apartment of Seoul and CLI showed that of 0.956 which is even higher. Result from the analysis, CLI shows high correlation with stock and real estate market, it is a good option to watch how CLI flows to predict stock and real estate market.

SMTG 알고리즘을 이용한 랜드마크의 고속정합

  • Seo, Seok-Bae;Kang, Chi-Ho
    • Aerospace Engineering and Technology
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    • v.4 no.2
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    • pp.230-235
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    • 2005
  • As a precedence research for the COMS(Communication, Oceanic, and Meteorological Satellite), this paper proposes the SMTC(Soble Masked Tracking Guideline) algorighm for a fast landmark matching. The experimental results show that proposed algorithm should recude a lot of calculative time.

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A Heuristic Algorithm for Resource-Constrained Multi - Project Scheduling (자원제약하의 복수 프로젝트 일정계획을 위한 휴리스틱 알고리즘)

  • Kong, Myung-Dal;Kim, Jung-Ja
    • IE interfaces
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    • v.13 no.1
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    • pp.110-119
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    • 2000
  • Resource-constrained project scheduling is to allocate limited resources to activities to optimize certain objective functions and to determine a start time for each activity in the project such that precedence constraints and resource requirements are satisfied. This study suggests a multi-project scheduling model which can level work loads, make the most of production capacity and restrain the delay of delivery by developing a heuristic algorithm which minimizes the project completion time and maximizes the load rate under resource constraints.

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AN ALGORITHM FOR COLLISION AVOIDANCE FOR ROBOTS WITH WORK ING SPACE

  • Lee, G.
    • Proceedings of the KIEE Conference
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    • 1991.07a
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    • pp.759-762
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    • 1991
  • In this paper an algorithm is presented which serves for collision avoidance between robots with working space. The method is based on the concept of a hierarchical coordinator and permits an on-line application. Computing possible collision points a collision_free trajectory for the robot with no right_of_way precedence is generated. The computations are based on the states of the robots concerned including their practicable accelerations and velocities.

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A framework for modelling and operation management of robotic assembly cells via knowledge base (지식베이스를 이용한 로보틱 조립셀의 모델링과 운영관리를 위한 프레임 워크)

  • 김대원;고명삼;이범희
    • 제어로봇시스템학회:학술대회논문집
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    • 1988.10a
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    • pp.374-379
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    • 1988
  • We propose a framework for modelling and operation management of robotic assembly cells via knowledge base. In the framework, each component of the cell is considered as a state variable, the relations among the state variables are stored in state transition maps(STMs) and then transformed into the form of knowledge. The assembly job tree(AJT) which includes the precedence relations and the constraints for assembly tasks is also described. Finally, an algorithm is presented to manage the cell operation.

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Manufacturing workflow modeling using Petri net (Petri net을 이용한 제조시스템의 워크플로우 모델링)

  • Kim T.;Seo Y.;Sheen D.
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2003.05a
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    • pp.821-826
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    • 2003
  • The Purpose of this paper is to automate the representation of manufacturing line using Petri net model. In the manufacturing cell, the line can be represented using workflow which is composed of Bill of Material (BOM) and Bill of Processes (BOP). BOP shows the precedence of processes and the relationship between assembly and disassembly. As a modeling scheme, generalized stochastic Petri net is adopted. For a problem domain with flexible manufacturing cell, Petri net model is made and behavioral properties are analyzed.

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Genetic Algorithm for Integrated Process Sequence and Machine Selection (통합적인 공정순서와 가공기계 선정을 위한 유전 알고리즘)

  • 문치웅;서윤호;이영해;최경현
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2000.04a
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    • pp.405-408
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    • 2000
  • The objective of this paper is to develop a model to integrate process planning and resource planning through analysis of the machine tool selection and operations sequencing problem. The model is formulated as a travelling salesman problem with precedence relations. To solve our model, we also propose an efficient genetic algorithm based on topological sort concept.

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Correlation embodiment between parts for efficient BOM use (효율적인 BOM 사용을 위한 부품간의 상관관계 구현)

  • 권영훈;김성근
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.10a
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    • pp.188-192
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    • 1997
  • A study was conducted to improve validity in new BOM structure through using the similitude of existing BOM in the PDM. The system is developed in Web-Based PDM environments using servlets and database. The system provides the correlation information between parts to inflect the reusability of existing BOM. User-defined correlation is used to inform the relations between design precedence and co-relations of parameters. Realistic application in injection mold production is constructed using this structure.

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