Evaluation And Application Of Production Logistics Based On Entropy Models In Discrete Manufacturing Enterprise

In a discrete manufacturing factory,the processing time of materials or parts is just a little part of production course and the most time of production course is that materials or parts are in one of logistics states of stagnation,loading and unloading,conveying,casing and carrying,etc.Therefore,to find out some suitable ways of controlling production logistics and effectively compare and evaluate different scheme or analyze and evaluate the running state and efficiency of production systems stands significent influence for correctly selecting more suitable logistic technical scheme and analyzing the key factor acted on production logistics,and improving holistic level of production logistics of civil enterprise by effectively controlling production logistics,logically preparing production materials and optimazing producing process according to the characteristic of manufactuing enterprise.In addition,a challenging and ever-changing environment of manufacturing systems leads that production systems are of uncertain characteristic of some randomicity and fuzziness. These uncertain characteristic can be described by entropy,a uniform concept,which is a basis to measure information of manufacturing systems by entropy theory.Using dissipative structure and information entropy relevant theoretical research achievements for reference,operating status of logistics,orderliness of structure and operation of production logistics systems and complexity of cellular manufacturing are deeply researched on the base of investigating and analysing on production logistics systems of discrete manufactuing enterprise to dicuss an approach to optimizing logistics based on entropic theory,and supply necessary foundation and technical support for management and decision,through developing entropy models of logistics systems of discrete manufactuing systems.Entropy theory of enterprise systems is discussed from measurement of information transforming,measurement of orderlessness and instability and measurement of uncertainty three parts.Entropic structure of manufactuing systems is divided by the nature of different parts of manufactuing systems and mutual relationship of different parts is expounded.Five entropy models of manufactuing systems are reduced and developed,ie.entropy change model,static entropy model,dynamic entropy model,lot entropy model and flexible routing entropy model,and their trait and applied domain are dicussed and illustrated in order to lay the foundation for the latter research.Dissipative structure model of enterprise systems is constructed according to mutation theory,which is applied to judge the condition that enterprise systems form dissipative structure.The process and condition of dissipative structure formed is researched by means of dissipative structure theory.The entropy change model drived by currency flow is set up and a formula by which value of entropy chang can be calculated is shown integrated the actual status of enterprise system,then an example is validated using the model and formula and the results met the fact well.The structural entropy model with dynamic and general characteristic is builded based on the mechanism of the sending and feedback of information according to definition of the structural entropy and using the principle of the conditional entropy and the classical probability.The structural entropy model of production systems is developed based on analyzing the characteristic of structure of production systems through disposing the model specially in order to calculate the model with more maneuverability.To solve the problem that it's short of quantificational ways when the different operational status that is worked by the different production mode or production structure about production logistics system is evaluated,from the concept of fuzzy entropy,the operational entropy model based on the element of production system is developed according to the principle of the information entropy and the definition of order degree.The operational evaluation system of production system is established on the basis of the factor of production logistics system.As a result,this quantificational way to evaluate the orderliness of production structure is validated well and extends application area of this operational entropy model by an empirical study.Utility of complexity of manufacturing systems is deeply analysed and the result that the complexity influences manufacturing systems is illuminated and the corresponding strategy is proposed according to the relationship between the complexity of manufacturing systems and its utility fuction.Based on the Shannon entropy,the models of the structural entropy and the operational entropy of cellular manufacturing systems are developed and the cognizance of the states of manufacturing resources is also illustrated.Using the above ways developed,the research based on entropy theory of production logistics actualized fore-and-aft cellular manufacturing in some job shop is successfully accomplished.The empirical study indicates that the proposed models are feasible and effective.