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Material Handling Improvement Methodology

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    Material Handling Improvement Methodology

    السلام عليكم ....

    أنا مهندس صناعي أحضر رسالة الماجستير في الموضوع أعلاه....

    ممكن لأي شخص يساعدني في إيجاد أي مواضيع حسب العنوان يراسلني ويكون مشكور.

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    محمد فوزى
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    http://www.calibex.com/
    http://www.dealtime.com/
    اليك اخى بعض الروابط للبحث بها

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    6. OVERVIEW OF COMPUTER-AIDED LAYOUT PROCEDURES



    Introduction

    The cycle of facilities design and management can be described as follows [IE September 80]. When a new plant is to be built, a site selection analysis must be conducted to determine where to build the plant. Once a site is selected, the preparation of data for the layout planning process is needed. This will eventually produce an overall layout. From this we proceed to developing a detailed layout. From the overall layout and the detailed layout we can develop a process to compare the alternatives. At this point we can use a computer for storing layouts with computer graphics. After this we continue with the installation of the best alternative. Once the installation is in place, the facilities management information system is maintained to provide information required when the next change is made. The loop is complete now. The current trend is to build an information-based manufacturing system.

    The first area in which the computer became a powerful tool was the overall layout development. In the early 60's heuristic procedures were developed to design block plan layouts. Today we can find a great number (possibly 100 or more) programs developed mostly as theses and dissertations in a number of universities. These procedures require a substantial amount of programming. These computer heuristic procedures can be grouped into three categories, depending on the logic used to develop the block plan: (1) construction heuristics; (2) improvement heuristics; and (3) network-based procedures.

    The input information required by computerized procedures consists of (a) from-to-chart or relationship chart; (b) area requirements for departments; (c) in some cases, cost information on material handling. As already explained, the relationship chart indicates closeness codes between departments (A = absolutely important, E = especially important, I = important, O = ordinary closeness, U = unimportant, X = not desirable to be close).

    Construction Procedures

    These procedures start with an open floor space and construct a single floor layout logically, based upon input data, a relationship chart, and space allocations. A partial list of these procedures includes:

    · CORELAP: Computerized Relationship Planning.
    · PLANET: Plant Layout Analysis and Evaluation Technique
    · ALDEP: Automated layout design Program

    The general steps of construction procedures are:

    1. Transplantation: input from problem is represented as input for program
    2. Selection: departments are selected according to their relationships and a closeness rank
    3. Placement: using the selection order and a logical procedure the layout is generated
    4. Evaluation: the layout is given a score that indicates its overall value

    Improvement Procedures

    These procedures require a feasible layout as input and continue to modify the layout by swapping areas and scoring the revised layouts until no further improvement can be found. The scores are based upon a from-to chart, which is part of the input. Two well-known improvement-type procedures are:

    · CRAFT: Computerized Relative Allocation of Facilities Technique
    · COFAD: Computerized Facilities Design




    Network-Based Procedures

    A smaller number of network-based procedures has been developed. The first procedure of this kind was RUGR. This procedure requires a relationship diagram as input. Another procedure in this class is PLANTAPT.

    A Micro-Computerized Procedure for Layout Design

    S. Khator and C. Moodie published the computerized procedure considered in this section in the March 1983 issue of Industrial Engineering. The program accepts input in the form of a relationship matrix. Then using the closeness codes A, E, I, O, U and X, it determines a closeness rank and a selection order of departments. After giving numerical value to each closeness code, the departments are placed on the layout according to the predetermined selection order, in such a way that the score of the layout will be as high as possible.

    Closeness ranks are determined on the basis of the number of A, E, I, O and X closeness relationships. A method for doing this, for example, is to consider first the departments having A relationships, then those having E relationships, and so on. The department having the largest number of A relationships is assigned rank 1. In case of ties, the rank will be decided by the largest number of E relationships; if ties continue to exist, they will be broken by the largest number of I relationships, and so on. If two departments have the same number of A, E, I and O relationships, the one having the lowest number of X relationships will be chosen first. Once all departments having A relationships are assigned closeness ranks, those departments having E relationships are considered, and so on. At the end of this procedure each department is assigned a rank, rank 1 for the most important, rank 2 for the one next in importance, and so on.

    Departments are selected according to the following procedure. The first department is that assigned rank 1. The second department is one having an A relationship with it; in case of ties, these will be broken by selecting the department having a higher level of importance, as measured by the closeness rank. Subsequent departments are chosen on the basis of the total number of A, E, I and O relationships between the department being selected and all those already selected, using the rank to break ties.

    Departments are then placed on the open floor space according to the selection order. In this procedure, those departments having high closeness relationships should be together. For each pair of adjacent departments the corresponding numerical value of the closeness relationship can be added to the score of the layout. The program prints the closeness ranks, the selection order, the closeness matrix (indicating which departments are adjacent by means of entries equal to 1; and entries equal to 0 otherwise), and the layout score.


    An Overview of Selected Available Programs

    I. Computerized Relative Allocation of Facilities Technique (CRAFT)

    This is a program designed to physically arrange the departments in a facility layout. It uses a path-oriented improvement routine based on pair-wise and three-wise exchanges of departments. The final layout is dependent on the initial layout. For this reason, it is suggested to try different initial layouts. The goal of the CRAFT program is to minimize the total transportation cost. The transportation cost for a particular move between two departments is defined as the product of the number of trips by the corresponding distance and then by a specified cost per unit distance. As a result of this, transportation costs are not directly associated with the material handling equipment used. The CRAFT procedure makes the following assumptions: (1) the facility has a rectangular or squared shape, and (2) the facility has no interior void spaces. These assumptions can actually be satisfied in most cases by creating dummy departments in the desired layout.

    Input

    1. Number of departments (up to 40).
    2. Plant area, length, and width.
    3. Number of bays.
    4. Department areas.
    5. Number of trips and cost per unit distance between departments.
    6. Initial layout as a sequence of departments (some can be fixed in the sequence).
    7. Selection of rectilinear or Euclidean distances to compute the cost.

    Output

    1. Graphical display of the arrangement.
    2. Total cost.

    Outline of Procedure

    1. Compute centroids for departments in the initial layout.
    2. Create distance matrix between centroids.
    3. Compute transportation cost of initial layout.
    4. Consider interchanges of department with equal area of with common borders.
    5. Select the interchange with the greatest cost reduction.
    6. Compute cost and repeat the procedure until no further reductions in cost are obtained.


    II. Computerized Facility Design (COFAD)

    This program is basically a modification of CRAFT to incorporate material handling alternatives. Its goal is to jointly select a layout and a material handling system that will result in a minimal or significantly reduced transportation cost. The cost associated with a move between two departments is defined as follows, depending on the type of equipment used: (a) For fixed-path equipment: (cost) = (variable cost) x (length of move) + (non-variable cost.) (b) For mobile equipment: (cost) = (variable cost) x (time of move) + (non-variable cost) x (equipment utilization.)

    Input

    The input data for running the program are in essence the same data required for running CRAFT. In addition, material handling equipment information is required.

    Output

    The output of the program consists of a factory layout and the recommended material handling system for each move between departments.

    Outline of Procedure

    Again, the procedure of the COFAD program follows the same general guidelines of the CRAFT
    procedure. In the case of COFAD, the overall procedure can be viewed as consisting of two phases:

    1. Alternate between improving a layout and improving its material handling system.
    2. Stop when fluctuations in flow volumes do not result in reduced total costs.


    III. Plant Layout Analysis and Evaluation Technique (PLANET)

    This program is used to generate and evaluate plant layouts. It does not restrict the final layout to having a uniform shape, nor does it allow fixing departments to certain locations resulting in unrealistic layouts. The best use of this technique is for generating an initial layout, which can be use as input to an improvement procedure. The measure of effectiveness is defined as total handling costs. The program assumes that the flow between departments is the same in both directions.

    Input

    The input data are again similar to those required by CRAFT. However, PLANET allows three different ways of describing the material flow: (1) by means of a production sequence of all parts to be moved within the facility, plus the cost per move; (2) by means of a from-to chart; (3) by a penalty matrix or relationship chart.

    Output

    The output consists of the plant layout along with its evaluation.

    Outline of Procedure

    PLANET uses three different methods for selecting departments:

    1. Start with the two departments with highest priority and highest flow-between cost. Keep on adding departments according to the highest priority and highest flow-between cost to any department in the group already selected.

    2. Start with the two departments with highest priority and highest flow-between cost. Keep on adding departments according to the highest priority and highest sum of flow-between costs to all the departments already selected.

    3. Start with the department of highest priority and highest sum of flow-between costs to all other departments. Keep on adding departments in the same manner. The first two selected departments are placed side by side, and the next selected department is located around the existing departments as to minimize the increase in handling cost.

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    continued....

    IV. Computerized Relationship Layout Planning (CORELAP)

    This is a layout construction program. It uses the total closeness rating (TCR), which is the sum of all numerical values assigned to the closeness relationships in a relationship chart (A=6, E=5, I=4, 0=3, U=2, X=1) between a department and all other departments. Its goal is to generate a layout using as measure of effectiveness a layout score that depends on the TCR.

    Input

    The input data required for running the program consist of departments information and a
    relationship chart.

    Output
    The output from the program is a plant layout along with the score.

    Outline of Procedure

    1. It starts by selecting the department with highest TCR and placing it in the center of the layout. Whenever there is a tie, the department with the largest area is selected or the department having the lowest department number in case of equal areas. The second department to be selected is one with an A relationship with the one selected; if none exists then an E relationship; if none exists then an I relationship, and so on. In case of ties use the department with highest TCR, or the one with largest area, or the one with smallest department number as before. The third department to be added is the one with an A relationship with the first department or with the second department. When such a department is not found, try a next-best relationship code until one is selected. In case of ties use the same tie breaking rules explained earlier. This procedure is repeated until the departments are assigned.

    2. Once a department is selected, it is located in such a way as to minimize the sum of the numerical values assigned to the closeness relationships with all the neighboring departments.

    3. A layout score is then computed for the final layout as the sum for all departments of the products of numerical closeness ratings and lengths of shortest paths.


    V. Automated Layout Design Program (ALDEP)

    This program has the same basic requirements and achieves the same objectives as CORELAP. It differs in the way the first department is selected and how ties are broken, which is at random. Another difference is that CORELAP tries to generate a good layout, while ALDEP can generate up to 20 different layouts, rates them, and lets the user make the selection.

    Input

    1. Department information.
    2. Relationship chart.
    3. Sweep width.
    4. Minimal closeness rating.
    5. Minimal layout score.

    Output

    The output from the program consists of up to twenty layouts with their associated ratings.

    Outline of Procedure

    1. The program starts by selecting a department randomly and adding departments in a manner, which is similar to that followed by CORELAP. In case of ties, they are broken randomly as well. In addition, any selected department must comply with a minimum closeness rating (user specified); if no department satisfies this requirement, the program will select one at random.

    2. The placement of departments is done by locating the first one on the upper left corner of the floor space, and proceeding downward with the remaining departments. The user specifies the width of the downward extension (referred to as the sweep width). When the bottom of the layout is reached it continues with a process of sweeping departments upwardly and downwardly until all departments are located.

    3. Once the layout is completed, it is rated by assigning values to the closeness relationships between adjacent departments. The score for the layout increases by 64 if two adjacent departments have an A relationship, 16 for an E, 4 for an I, 1 for an O, and nothing for a U; the score is decreased by 1024 for an X relationship.


    VI. BLOCK PLAN

    The program generates and evaluates block type layouts. It features different layout generation methods and multi-story layouts. It does both, generation and improvement of layouts. The generation is done by either randomly locating the departments or by considering the relationships between departments. The improvement is done by pair-wise exchange of departments.

    Input

    1. Number of departments (up to 18).
    2. Department names and areas.
    3. Relationship chart or from-to-chart.
    4. Length/width ratio of the plant.
    5. Product information: number of products, number of unit loads, department sequence
    6. Information of any department with fixed location.

    Output
    The output from the program consists of a graphical display of the plant layout along with the corresponding score.

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    موقع مفيد جدا

    انصحك اخي العزيز بزيارة هذا الموقع وانشالله سوف تستفيد
    http://www.mdcegypt.com/
    مع تحياتي

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    Exclamation Computerized Relative Allocation of Facilities Technique

    الأخ العزيز : صناعي 1
    نرجو منك إرسال أو تنزيل برنامج craft لأننا بحوجة ماسة إليه وذلك في أقرب فرصة ممكنة
    وإعطائنا رقم هاتفك

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    مع المحبرة إلى المقبرة

  8. [8]
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    اقتباس المشاركة الأصلية كتبت بواسطة أنس عمر مشاهدة المشاركة
    الأخ العزيز : صناعي 1
    نرجو منك إرسال أو تنزيل برنامج craft لأننا بحوجة ماسة إليه وذلك في أقرب فرصة ممكنة
    وإعطائنا رقم هاتفك
    أخي الكريم في هذه الصفحة
    http://engr.smu.edu/%7Ebarr/pomlib/html/craft.html
    يوجد برنامج يمكن استخدامه من خلال المتصفح لحل مسائل CRAFT و لكن لا يوجد لدي برنامج
    و يمكننا التواصل من خلال المنتدى حتى تعم الفائدة

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  9. [9]
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    السلام عليكم

    السلام عليكم .... وجدت هده المجلة وانشاء الله تنفعك في بحثك
    Material Handling Network Magazine - May 2009



    الرابط

    http://rapidshare.com/files/23584802...0905-win32.zip



    ادا اعجبتك المجلة ابلغني لأنه يوجد اعداد أخرى مع تمنياتي بالتوفيق

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  10. [10]
    zidaan
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    السلام عليكم وجدت لك هدا الكتاب اتمنى أن تستفيد منه

    Introduction to Material Handling

    وهدا رابط الكتاب :

    http://ifile.it/gliruad/Materials_Handling.rar

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