• 제목/요약/키워드: Cellular Formation

검색결과 925건 처리시간 0.026초

다목적 셀 형성을 위한 유전알고리즘 (A Genetic Algorithm for A Cell Formation with Multiple Objectives)

  • 이준수;정병호
    • 산업경영시스템학회지
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    • 제26권4호
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    • pp.31-41
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    • 2003
  • This paper deals with a cell formation problem for a set of m-machines and n-processing parts. Generally, a cell formation problem is known as NP-completeness. Hence the cell formation problem with multiple objectives is more difficult than single objective problem. The paper considers multiple objectives; minimize number of intercell movements, minimize intracell workload variation and minimize intercell workload variation. We propose a multiple objective genetic algorithms(MOGA) resolving the mentioned three objectives. The MOGA procedure adopted Pareto optimal solution for selection method for next generation and the concept of Euclidean distance from the ideal and negative ideal solution for fitness test of a individual. As we consider several weights, decision maker will be reflected his consideration by adjusting high weights for important objective. A numerical example is given for a comparative analysis with the results of other research.

제조 셀 구현을 위한 군집분석 기반 방법론 (Cluster Analysis-based Approach for Manufacturing Cell Formation)

  • 심영학;황정윤
    • 산업경영시스템학회지
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    • 제36권1호
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    • pp.24-35
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    • 2013
  • A cell formation approach based on cluster analysis is developed for the configuration of manufacturing cells. Cell formation, which is to group machines and parts into machine cells and the associated part families, is implemented to add the flexibility and efficiency to manufacturing systems. In order to develop an efficient clustering procedure, this paper proposes a cluster analysis-based approach developed by incorporating and modifying two cluster analysis methods, a hierarchical clustering and a non-hierarchical clustering method. The objective of the proposed approach is to minimize intercellular movements and maximize the machine utilization within clusters. The proposed approach is tested on the cell formation problems and is compared with other well-known methodologies available in the literature. The result shows that the proposed approach is efficient enough to yield a good quality solution no matter what the difficulty of data sets is, ill or well-structured.

Quenching을 이용한 $1\mu{m}$ 미만의 Cell 형성 (Formation of cell under $1\mu{m}$ by quenching)

  • 이병희;차성운
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 춘계학술대회 논문집
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    • pp.1420-1423
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    • 2005
  • Micro Cellular Plastics create a sensation at polymer industrial for lowering product cost & overcoming a lowering of mechanical intensity. Reduction of MCPs cell size increases the intensity of MCPs. This research based on the experiment about cell size reduction method. At this study, Quenching & Pressure foaming process are introduced to one of methods. Conclusion of study is that Quenching process is the simplest process for nano cell formation.

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Every Single Cell Clones from Cancer Cell Lines Growing Tumors In Vivo May Not Invalidate the Cancer Stem Cell Concept

  • Li, Fengzhi
    • Molecules and Cells
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    • 제27권4호
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    • pp.491-492
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    • 2009
  • We present the result of our research on the tumorigenic ability of single cell clones isolated from an aggressive murine breast cancer cell line in a matched allografting mouse model. Tumor formation is basically dependent on the cell numbers injected per location. We argue that in vivo tumor formation from single cell clones, isolated in vitro from cancer cell lines, may not provide conclusive evidence to disprove the cancer stem cell (CSC) theory without additional data.

셀 생산방식에서 자기조직화 신경망과 K-Means 알고리즘을 이용한 기계-부품 그룹형성 (Machine-Part Grouping in Cellular Manufacturing Systems Using a Self-Organizing Neural Networks and K-Means Algorithm)

  • 이상섭;이종섭;강맹규
    • 산업경영시스템학회지
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    • 제23권61호
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    • pp.137-146
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    • 2000
  • One of the problems faced in implementing cellular manufacturing systems is machine-part group formation. This paper proposes machine-part grouping algorithms based on Self-Organizing Map(SOM) neural networks and K-Means algorithm in cellular manufacturing systems. Although the SOM spreads out input vectors to output vectors in the order of similarity, it does not always find the optimal solution. We rearrange the input vectors using SOM and determine the number of groups. In order to find the number of groups and grouping efficacy, we iterate K-Means algorithm changing k until we cannot obtain better solution. The results of using the proposed approach are compared to the best solutions reported in literature. The computational results show that the proposed approach provides a powerful means of solving the machine-part grouping problem. The proposed algorithm Is applied by simple calculation, so it can be for designer to change production constraints.

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Alterations of Protein Expression in Macrophages in Response to Candida albicans Infection

  • Shin, Yu-Kyong;Kim, Ki-Young;Paik, Young-Ki
    • Molecules and Cells
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    • 제20권2호
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    • pp.271-279
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    • 2005
  • Although macrophages are an important first line of cellular defense, they are unable to effectively kill phagocytosed C. albicans. To determine the physiological basis of this inability, we investigated the alterations of macrophage proteins caused by C. albicans infection. Since the formation of C. albicans hyphae caused cell death, proteins were prepared 3 h after infection and examined by two-dimensional gel electrophoresis (2-DE). The most prominent changes were in glycolytic enzymes, which could have caused energy depletion of the infected cells. Also changed were proteins involved in maintenance of cellular integrity and NO production. Treatment of the macrophages with either cytochalasin D or taxol did not alter their inability to kill C. albicans. Our results indicate that multiple factors contribute to cell death as the pathogenic form of C. albicans becomes fully active inside macrophage cells.

Elastic rotational restraint of web-post in cellular beams with sinusoidal openings

  • Durif, Sebastien;Bouchair, Abdelhamid;Bacconnet, Claude
    • Steel and Composite Structures
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    • 제18권2호
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    • pp.325-344
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    • 2015
  • Experimental tests on cellular beams with sinusoidal openings showed two main failure modes around the openings. They concern the formation of four plastic hinges and the local instability of the sinusoidal part of the opening. In parallel, numerical analysis of the sinusoidal part of the opening revealed the existence of an elastic rotational restraint between the intermediate web-post and the adjacent opening panel. The aim of the present study is to present an approach to quantify this rotational restraint. Through the response surface method, a mathematical model is proposed. It shows a great ability to predict the rotational restraint value as a function of the geometrical parameters of the opening. This model can be used to perform an extensive study with various geometrical configurations of beams with the aim to develop a reliable and realistic analytical model predicting the resistance of the sinusoidal openings.

Wound-Induced Hair Follicle Neogenesis as a Promising Approach for Hair Regeneration

  • Chaeryeong Lim;Jooyoung Lim;Sekyu Choi
    • Molecules and Cells
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    • 제46권10호
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    • pp.573-578
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    • 2023
  • The mammalian skin contains hair follicles, which are epidermal appendages that undergo periodic cycles and exhibit mini-organ features, such as discrete stem cell compartments and different cellular components. Wound-induced hair follicle neogenesis (WIHN) is the remarkable ability to regenerate hair follicles after large-scale wounding and occurs in several adult mammals. WIHN is comparable to embryonic hair follicle development in its processes. Researchers are beginning to identify the stem cells that, in response to wounding, develop into neogenic hair follicles, as well as to understand the functions of immune cells, mesenchymal cells, and several signaling pathways that are essential for this process. WIHN represents a promising therapeutic approach to the reprogramming of cellular states for promoting hair follicle regeneration and preventing scar formation. In the scope of this review, we investigate the contribution of several cell types and molecular mechanisms to WIHN.

High Glucose Inhibitory Effects on Bone Formation in UMR106 Cells

  • Kwon, Eun-Hee;Jung, In-Ok;Kim, Sung-Jin
    • Biomolecules & Therapeutics
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    • 제11권2호
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    • pp.81-84
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    • 2003
  • Recently, diabetes has been found to be associated with osteoporosis. Specially in IDDM. In both type I and type II diabetes, glucose levels are elevated. Thus, a linkage between high glucose and osteoporosis can not be ruled out. In this study, an attempt has been made to observe the effect of high glucose on bone formation; osteoblast like UMR 106 cells were treated with high glucose (22 mM, 33 mM) for 1, 3 or 7 days. The high concentration of glucose inhibited markers. of bone formation activity such as alkaline phosphatase and collagen synthesis. In addition, reduction in the level of total cellular protein in response to high glucose was also observed. This study showed high glucose concentration could alter the bone metabolism leading to a defective bone formation and thus paving the linkage of such situation to diabetic complications.

Fuzzy ART 신경망 기반 폐제품의 리싸이클링 셀 형성 (Fuzzy ART Neural Network-based Approach to Recycling Cell Formation of Disposal Products)

  • 서광규
    • 대한안전경영과학회지
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    • 제6권2호
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    • pp.187-197
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    • 2004
  • The recycling cell formation problem means that disposal products are classified into recycling product families using group technology in their end-of-life phase. Disposal products have the uncertainties of product condition usage influences. Recycling cells are formed considering design, process and usage attributes. In this paper, a new approach for the design of cellular recycling system is proposed, which deals with the recycling cell formation and assignment of identical products concurrently. Fuzzy ART neural networks are applied to describe the condition of disposal product with the membership functions and to make recycling cell formation. The approach leads to cluster materials, components, and subassemblies for reuse or recycling and can evaluate the value at each cell of disposal products. Disposal refrigerators are shown as an example.