Hierarchical Modeling of Processes and Operations

In the first chapter of Volume 2 (hereinafter referred to as 21 1) we presented the general framework of MODEL.LA., a modeling language that can capture the hierarchical and distributed character of processing systems. We will employ all aspects of MODEL.LA. in order to develop a complete and consistent description of plants that will satisfy the modeling needs for the synthesis of operating procedures. 

In this section we will offer several illustrations of the various aspects of nonmonotonic operations planning (discussed in earlier sections) including the following (1) development of hierarchical models for the process and its operations, (2) conversion of constraints to temporal orderings of primitive operations, and (3) synthesis of complete plans. 

These concepts are implemented in the integration platform CHEOPS Component-Based Hierarchical Explorative Open Process Simulator) [252, 409, 462]. The platform provides generic component prototypes and interfaces for the integration of models, solvers, and tools. The generic components are instantiated at run-time by concrete software components and classes representing actual unit operation models, solvers, etc. That way, arbitrary components from the list of available components can be used in the simulation. The list of model and solver components can easily be extended with the components that comply with the abstract structure and interface definitions. 

Mission and activity models describe in a hierarchic structure the goals and the available recovery activities from missions-not-as-planned that make up the human operators high-level behavioral repertoire in the mission. The next level of decomposition of the action of the mission is a set of high-level procedures (that can be stored as a fairly generic set of routines, e.g., look at or fixate). Finally, there are the specific activities in active action packets RAPS, which are the process by which the human operator affects the simulation. 

ABSTRACT By analyzing the hierarchy of safety factors in purification plant of natural gas, they are divided into personnel, equipment, environment and management. After the study of safety index, evaluation methods and fuzzy arithmetic method for each hierarchy, its fuzzy evaluation flow is given. During the evaluation, the weight of the factors and each hierarchy is decided by analytical hierarchical process, and the operational criterion adapts maximum membership degree. And this model is exemplified in purification plant of natural gas. The results show that the second fuzzy evaluation is effective to assess purification plant of natural gas. 

The simulation of the model requires the speciftcation of the maximum availability of all the resources within the plant. These conditions cause constraints to be placed on the simulation flow in the model based on the availability of resources. User specified the purchase cost/cost per use of the resources or built-in cost model based on costestimating factors for biopharmaceutical process equipment were used (Remer Idrovo, 1991). The series of process steps and ancillary operations to manufacture the product, prepare the equipment, test the sample and document the batch were then defined in their respective hierarchical workspaces. Finally, the factors for mass balance calculations were input to determine the characteristics (i.e. mass, volume) of the process streams from each process step. 

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