AN EFFECTIVE SOFTWARE SOLUTION FOR PLANNING AND SCHEDULING

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1 6th International DAAAM Baltic Conference INDUSTRIAL ENGINEERING April 2008, Tallinn, Estonia AN EFFECTIVE SOFTWARE SOLUTION FOR PLANNING AND SCHEDULING DrD. Eng. Bancila, D; Prof. PhD. Eng. Buzatu, C Abstract: On the basis of an original logical diagram of different marks machining scheduling algorithm, this paper describes the general structure of a specialized software solution. By easily integrating planning and scheduling algorithms the software is developed to achieve optimal results in the most diverse working environments. The paper presents the program steps and the necessary data to be known in order to obtain the optimal planning and scheduling structure. Key words: software, scheduling, genetic algorithm. 1. INTRODUCTION The faster changes in the business world and the more complex activities that take place inside a company demand a permanent and fast adaptation to its needs that often cannot be performed by the human factor. Hence, ERP systems were crated as a solution to these challenges, being able to process a very high level of information and data in order to optimize the processes. The production flow is the most important process in the value chain of a production company, and the quality of the final products is essential. In order to achieve these results the efficiency of the management informatic system is very important. Only by implementing an informatic solution perfectly suitable for the activities of a production company it can be ensured its competitivity on the market. 2. THE SOFTWARE PRESENTATION The presented software has been developed by the author as part of his doctoral thesis, having a series of advantages over the existing scheduling and planning software solutions: Minimum time and maximum efficiency during the implementation process; Higher integration level for component module; Intuitive interface, leading to shorter tutoring time. The software application is structured on three modules: a general information module, a production module, for the assistance of the entire production cycle (having as input data the clients orders or the production planning flow). The third module is the production planning module. The three modules are described as follows. 2.1 General information module Here, data referring to the organizational structure, employees, clients, measurement units, functions, items (all raw materials, tools, half-finished materials) are introduced. 2.2 The production module The production module gives multiple facilities regarding the production preparing, programming/ launching and tracking. Production tracking, with the help of this module, allows the control and the quality enhancement of the final product, also eliminates down-time and reduces scrap.

2 2.2.1 Production Preparing Production preparing starts by describing the final products, subsets, markers, as a leveled arborescent structure. A technological chart (based on operations, technological characteristics, materials catalogs) is assigned to each processed component (marker, subset, finite products) that specifies: Product grade list = materials chart, processed components (blanks, markers, subsets), consumption rate and alternative components list; Production technology = operations list, in the technological order, specifying for each operation: The operation time rate (preparing time for human factor and for the machine, and manufacturing time for human factor and machine); Work post (machine, team, branch); SDV necessary; Technological characteristics set. Technological documentation contains a series of reports: Product grade list; Centralizing technological chart; SDV list; Manufacturing extras; Materials list; Operations chart; Tracking list; Components specifications on operations class; Components specifications on work space class Production programming and launching Production programming tool allows planning/ launching each client or production flow order. Each order can be associated to a branch responsible for handing the finite product (even if the final product and its components are passed in several branches during the production flow). To each order is attached a starting and an ending time that are taken from client order data and can be adjusted before the effective production launching (production command activation). All documents in the production launching documentation can be generated (in the case when in the organizational structure are several branches/workshops) at the branches (workshops) or work space (machines) levels the operations were defined for in the technological chart. In order to allow tracking (production, consumption, manufacturing) on components also, the system generates a set of commands (internal orders) for each of them. Several marks (launched production value, load capacity of each machine) can be tracked. The reports relying on orders from the production plan regard: Preparing program; Production program; Quantity/ Value production program; Contracted production; Time and manufacture/operations centralizing; Time and manufacture/order centralizing; Launched manufacturing/ work space classes centralizing; Launched manufacturing / workshops centralizing; Branch level production program; Branch level time and manufacture report. Taking into consideration the production specify, the set of suitable production launching documents are selected, the launching documentation containing: Consumption form; Consumption form from branch orders; Components detailed limit chart; Product centralized consumption limit chart; Orders centralized collective consumption chart; Work form; Work arrangement / price categories centralizer; Materials necessary; SDV necessary; Machines necessary; Co-operation necessary; Production chart.

3 2.2.3 Production tracking As the production consumption and manufacturing are registered, production flux state can be tracked. One can choose between a detailed marker/ subset/ finite product tracking and only a finite product tracking. The detailed tracking can be performed either by operating the components delivery documents, or by operating the performances of components technological flux operations. During production processes one can accentuate the conformability of each part, being able to supplement orders from the scrap forming point. The consumption registration can be performed either on the materials specified in the product s technological chart, or on the material specified in the afferent derogation from the materials in the product s technological chart. Taking into consideration the chosen software settings one can control production and consumption operations by allowing or not the input materials or final products quantities to exceed the quantities specified in order launching. An order can have several states: inactive, active, suspended, annulled and finished, and as the production and consumption are reported, an order reaches the finished status. The system allows establishing, at technological chart level, the mandatory returns of materials. Thus the system does not allow the order to pass into the finished state before these excess material quantities were redeemed. The direct price calculus for each production order, split in user configured cost elements, is made in order to improve the economical performances, and the reports that allow tracking the production states are: Branch orders tracking; Internal orders tracking; Effective consumption for each order; Effective production for each order; Manufacturing for each order; Produced goods; Time and manufacturing/ operations centralizer; Time and manufacturing/ order centralizer; Branch production schedule; Branch time and manufacturing ratio; Unfinished production. 2.3 Production Planning This module (fig. 1) allows building an unlimited number of branch orders planning scenarios, as well as obtaining information about time and space (work post) planning and the load for each work post or machine. Fig.1. Production planning module When planning some considerations are taken into account: Production planning considers work posts load capacity; Orders planning is based on starting time of each job; The maximum number of machines from the technological chart of each operation,

4 as well as the work posts attendance is considered; One operation is planned on a compact interval (without interruption from other orders); It is considered that the raw material is assured, so that the dependencies between operations and the material needs are fully satisfied and do not interact with the planning activity. In order to obtain a planning scenario some information is needed. This information regards: Company schedule; Work plan; Work posts with information regarding: Number of available machines; Associated work plan; Working team for each work post; Number of functioning hours in each shift; Maximum number of workers for each work post; Operations; Technological chart, with information regarding: The attendance mode of each work post for each operation; Maximum number of machines that can be allocated to an operation. Once a planning scenario is created, one can intervene on the planning, and analyze the results obtained by modifying the following elements: Work posts; Work plan for each work post; Attendance degree for each work post ; Operations duration; Maximum number of machines for each operation; Quantity of products to be produced. When consulting the planning scenarios several filters regarding branch orders, internal orders, workshops, work posts, operations can be applied. 3. THE USED ALGORITHM The used algorithm for production planning (fig.2) is presented in [ 1 ] and it consists of a hybrid algorithm (HA) based on the fundamentals of genetic algorithms and heuristics [ 2 ], being modified according to the following steps: 1. Generate an initial population. 2. Produce a new generation P. 3. Invert the new obtained P generation to produce InvP generation. 4. Evaluate the objective function for both P and InvP generations. 5. Choose from P and InvP the best n individuals to form the next generation (n number of the individuals from a generation). 6. Repeat Steps 2 5 until the prescribed stop criterion is satisfied. Fig.2. Used algorithm 4. COMPUTATIONAL RESULTS In order to highlight the efficiency of the presented software, a practical problem was considered, as follows: the production of a bearing company needs to be scheduled. As input data we have: time period of one month, a number of 20 employees, the organizational structure of the company and the current scheduling situation. For the next month period, three

5 clients orders consisting in three different marks are to be planned. We will try to solve the given problem using three different software solutions: AIS by ADCOS Romania [ 3 ]; EMSYS by Prodinf Software [ 4 ]; Our software solution. The Gantt diagrams resulted from the production scheduling in these three cases are presented in fig.3-5. Fig.3. Gantt diagram in the case of production scheduling with AIS Fig.4. Gantt diagram in the case of production scheduling with EMSYS Fig.5. Gantt diagram in the case of production scheduling with our software solution 5. CONCLUSIONS In this paper, a scheduling software application was presented. The algorithmic structure of the application was described, along with the necessary steps and data. For production planning and tracking activities a scheduling algorithm was integrated within the software. The efficiency of our software solution is shown in section four by the means of a practical problem. 6. REFERENCES 1. Buzatu, C., Bancila, D., A Hybrid Algorithm for Job Shop Scheduling, 6th International DAAAM Baltic Conference "INDUSTRIAL ENGINEERING, Bancila, D., Buzatu, C., The Influence of Priority Rules in Local Heuristic Based Job Shop Scheduling, Bulletin of the Transilvana University of Braşov, 2005, 12, ( ; 10:40) ( ; 12:08). 7. ADDITIONAL DATA ABOUT AUTHORS DrD. Eng. Băncilă Daniel / 42 Gen. Mociulschi Street, ap. 8 / Braşov, România / phone: / d.bancila@unitbv.ro ; Prof. PhD. Eng. Buzatu Constantin / 29 Neptun Street, ap. 7 / Braşov, România / phone: / cobuzatu@unitbv.ro.

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