Simulation Expert System Research Articles

Trends and progress of the theory of countercurrent extraction and rare earth separation technology

<p indent=0mm>Rare earths are significant for new material developments. China has the largest proved reserve of rare earths, and developed leading theories and technologies of rare earth extraction separation in the world. To adapt to the new requirements of environment protect and intelligent manufacturing in the last two decades, rare earth separation technologies behave the development trends of continuous chromatography, higher product purity, automatic control and process coupling. A flow-sheet with hyperlink extraction technology presents the separation efficiency as continuous ion exchange chromatography. Improvements on cause-effect analysis and control technologies of cross contamination during the process deepened the purification limitation by extraction separation. Automatically controlled production based on a special simulation expert system for flow-sheet optimization design will provide effective guarantee for the quality and stability of rare earth products. The coupling of extraction separation with other processes has proved to be a new idea to further improve green manufacturing level of rare earth separation. Herein, in combination with our recent studies, we have introduced the trends and progress of the theory of countercurrent extraction and rare earth separation technology.

Expert System for Simulation of Pest and Disease Diagnosis in Onion Plant Using Putty Shafer Method and Rule-Based Approach

The expert system is trying to adopt a system of human knowledge into a computer so that the computer can solve problems like the experts. The expert system is well designed in order to solve a particular problem by mimicking the work of the expert. The development of an expert system is expected to be resolved problems with the help of experts. The problems addressed by an expert not only the problems that rely on algorithms but sometimes elusive problems. An expert with knowledge and experience can overcome these problems. The application of an expert system in this study is made to diagnose pests and diseases in onion plants based on the web. The Data Collection method used is literature studies, interviews and observation. The stages of research used are literature review, data processing analyst, and Onion analyzed and photographed which then is uploaded and analyzed, Dempster Shafer method, application development, evaluation. In the last stage is the pilot study conducted using a Blackbox method and testing to the user. The result of the research is in the form of an expert system application that can diagnose pests and diseases of onion as many as 7 types of diseases. The output system is in the form of onion disease searching result obtained based on the symptoms inputted by the user. The result of Blackbox Testing is all functions of the application successfully run well. Testing to the users rated well both appearance and information of the application.

Design and Implementation of Rule Inference Engine in ESTSWEU

According to the characteristics and requirements of the teaching simulation expert system for weapon equipment utilization, the expert system inference module designs a rule-based reasoning engine technology, the separation of equipment using expert knowledge and control strategy is realized, and the administrator can edit expert knowledge, enhances the expansibility and flexibility of the system. Firstly, this paper introduces the structure, function and equipment rule type of ESTSWEU, and then expounds the general framework and working principle of rule reasoning engine in weapon equipment teaching simulation expert system, and finally the implementation of rules in the rule inference engine framework, the XML-based storage technology, the rule base interface, the equipment database and access interface, the object-oriented rules engine call interface, the rule execution engine processing flow and the establishment of the rule base are introduced in detail.

Throughput accounting and performance of a manufacturing company under stochastic demand and scrap rates

Theory of constraints (TOC) has emerged as an effective management philosophy suggesting practical solutions to various complex problems including product mix problem. Scholars have shown the superiority of various optimization (and artificial intelligence) approaches over the TOC-based heuristic to a “static” product mix problem, but have failed to see TOC as a whole, i.e. to take into consideration the impact of resource inter-dependencies, feedback loops, and importantly, statistical fluctuations ever present in any dynamic business environment. We proposed a system dynamics (SD) based simulation model to investigate product-mix problem under stochastic demand and scrap rates. We analyzed various scenarios by employing the drum-buffer-rope approach and constraint focused systematic scrap rate reduction approach, and importantly, evaluating performance using throughput accounting based global measures such as throughput and inventory. We conclude this paper by suggesting that future research efforts should be directed to develop an enabling hybrid expert simulation system to learn fundamental and powerful concepts underlying the theory of constraints.

Simulation expert system for making students’ college decisions

A brief survey has been performed of foreign investigations on the modeling of the process of decision making about student choices of colleges and universities; a suitable simulation expert system has been developed at a conceptual level.

Expert system for simulation of metal sheet stamping

Stamping processes are frequently used in the automotive industry. In an attempt to reduce developing times and costs, conventional design and manufacturing procedures are being changed. Finite element simulations have proved to be a good help in the design and analysis of these processes. The main problem of these simulations is that they are quite difficult to perform and that there are several non-trivial questions that the user has to answer before achieving a good model. In this work, a new application has been designed. It combines the usability of a custom application with the power of such a tool as the finite element method. To design this application, a lot of questions regarding FEM simulation of stamping processes have been analyzed. The result is a methodology to automate simulations of stamping processes where the user does not need to have deep knowledge of the finite element software. Such methodology has been successfully employed in a Spanish manufacturing industry of automotive components.

Structural and functional design of WWTP operation decision support system with a case study

This paper developes the WWTP operation decision support system (ODSS) to simulate the dynamic behavior of the WWTP treatment process based on ASMs (activated sludge models) and WWTP experiential knowledge. The novel structure and functions of ODSS can offer more flexible and general instructions to the WWTP operations. The three independent sub-systems, namely expert system, simulation system and training system, can cooperate to achieve many more functions such as operation alert, fault diagnosis, process simulation and so forth. The expert system based on the dynamic simulation, an essential part of WWTP ODSS, has been proved to be feasible and effective by the implementation at Fang Zhuang WWTP. Our results indicated that the WWTP ODSS has significant potential for improving plant performance and reducing treatment costs by assisting the operators at the decision-making level.

A production rescheduling expert simulation system

The job shop rescheduling problem is considered as a particularly hard combinatorial optimization problem. This problem deals with uncertainty caused by the exterior business environment and interior production conditions. Production rescheduling is a common practice in Chinese manufacturing firms. Four sources of production disturbances have been identified: (1) incorrect work; (2) machine breakdowns; (3) rework due to quality problem; and (4) rush orders. These disturbances are fuzzy and random. In order to solve this ill-structured production problem, a production rescheduling expert simulation system is proposed in this paper. The production rescheduling expert simulation system integrates many techniques and methods, including simulation technique, artificial neural network, expert knowledge and dispatching rules.

Proposing an architectural framework of a hybrid knowledge‐based system for production rescheduling

An architectural configuration of a knowledge‐based system for production rescheduling reported in this paper uncovers a number of points of interest to practitioners as well as researchers. The study shows that knowledge‐based methods applied to production rescheduling are a valuable approach for manufacturers to manage production disturbances and deliver customer orders on time. Very often, developing an effective scheduling system whilst solving some problems requires an appropriate combination of a rigorous analysis of the production system state and the rules of thumb used by the human scheduler. In the actual performance of this hybrid system, an expert simulation system was used to produce new schedules that fit the real production environment.

Lan Configuration Decisions: An Expert Simulation System (ESS) Approach

The Local Area network (LAN) client/server platform is the information technology (IT) architecture of choice today. As such, the complex tasks of LAN design, development, and performance are of tremendous importance. Human experts in this field are scarce and expensive; therefore, an alternative approach to designing LANs is needed. The objective of this study is to validate a synergistic approach for designing superior LAN configurations. Meeting this objective required the development and evaluation of a combination expert system and simulation system into an expert simulation system (ESS) for LAN design with cost constraints. To determine the effectiveness of the ESS, simulated response times of LAN designs generated by an ESS, an expert system, and by human experts with the aid of a LAN simulation package are compared. Results indicate that the ESS developed in this study is a valid approach that can be used by LAN decision-makers to produce superior LAN configurations.

Modelling, scheduling and simulation of flexible manufacturing systems using extended stochastic high-level evaluation Petri nets

The present paper presents the new extended stochastic high-level evaluation Petri nets (ESHLEP-N) which are more suitable for modelling and simulation of flexible manufacturing systems (FMSs). The advantages of ESHLEP-N lie in the fact that their resulting models are not only simpler, more intuitive and more descriptive, but also of the more inferential and decisive power. Based on the ESHLEP-N model, the scheduling and simulation expert system (ES) for the FMS is designed and established. With the help of the ES, we will put forward some new dynamic-rescheduling rules aiming at reducing no-inputs and blockings. The simulations show that the throughputs of the rescheduling can increase on an average by 6.48% as compared with those of the non-rescheduling. The comparison between the experiment on the real FMS and the simulation on the ES indicates that the ES is effective.

Knowledge engineering approaches in developing expert simulation systems

Two approaches to knowledge engineering are demonstrated using the soybean insect pest management expert simulation system SMARTSOY. SMARTSOY incorporates the soybean crop growth simulation model SOYGRO as part of its knowledge base. The positivistic approach to knowledge engineering attempts to duplicate thought processes of domain experts in order to arrive at conclusions while the normative approach attempts to duplicate the conclusions of domain experts without consideration of their thought processes. These contrasting approaches require different knowledge engineering techniques and validation procedures. Validation, evaluation and calibration of the two approaches are demonstrated using SMARTSOY for 84 field scenarios.

An expert simulation system for the master production schedule

Both simulation and expert systems are computer-based modern management decision supporting techniques. In this paper, an expert simulation system for the master production schedule ( essmps) is presented. By integrating expert system, simulation, mathematical optimization and data base techniques, essmps has been developed on an IBM PC using PC Plus expert system building tool, siman simulation language, fortran 77 and d base iii Plus to help the production manager to work out a satifactory master production schedule.

A design of expert system architecture for communications engineering simulation

Simulation expert system architecture for communications simulation including the features of common data structure, top- down information driven technique, optimization, and expert system approach is addressed. The concepts can be combined to implement a very user-friendly simulation system for either a novice or experienced user. The architecture block diagram of the simulator is discussed to highlight the important functions. Complete or partial features addressed can be adopted in any simulator design.

Modelling the software development process using an expert simulation system having fuzzy logic

AbstractThis paper describes an intelligent computerized tool designed to aid managers of software development projects in planning, managing and controlling the development process of medium‐ to large‐scale software projects. Systems dynamics is used to model and simulate the dynamic process of software development. The software development process is affected by some imprecise and vague variables that are treated as fuzzy variables. The simulation model is integrated with two expert systems. The fuzzy input variables to the system dynamics simulation model are handled by an input expert system having fuzzy logic. This expert system is designed to check the consistency of input variables. The simulation results are analysed by an output expert system having fuzzy logic. This expert system is designed to make recommendations based on experimentation with the simulation model.

An expert system for extreme wind simulation

Research efforts have been made to improve the methods of utilizing short-term records for estimating long-term extreme winds for design purposes. Recent approaches to the problem include our Markov models for extreme wind simulation applicable to a well-behaved climate as well as typhoon-prone regions. Recently, we realized that the application of these simulation models, for inexperienced users, is tedious, painstaking and time-consuming. Therefore, our current effort is to utilize an expert system shell to facilitate the application of the simulation models in a microcomputer environment. An application of this approach is illustrated.

A farm level expert simulation system to aid farmers in selecting among crop insurance strategies

An expert simulation system (ESS) in aid U.S. farmers select crop insurance strategies is presented. The ESS, entitled CIRMAN, relies on stochastic simulation models to analyze the problem and formulates a series of rules to make recommendations. The following lexiographic hierarchy of rules is used to rank the strategy options: (1) risk efficiency; (2) probability of farm survival; (3) probability of economic success; (4) expected value of after-tax net present value of family withdrawals plus the change in net worth over the planning horizon; (5) average expected annual net-cash farm income; and (6) average expected value of ending net worth. CIRMAN presents a recommendation and explanations on why a strategy was recommended and how it compares to specified alternatives.

An expert system for extreme wind simulation

Research efforts have been made to improve the methods of utilizing short-term records for estimating long-term extreme winds for design purposes. Recent approaches to the problem include our Markov models for extreme wind simulation applicable to a well-behaved climate as well as typhoon-prone regions. Recently, we realized that the application of these simulation models, for inexperienced users, is tedious, painstaking and time-consuming. Therefore, our current effort is to utilize an expert system shell to facilitate the application of the simulation models in a microcomputer environment. An application of this approach is illustrated.

Computer-aided software development process design

The authors describe an intelligent tool designed to aid managers of software development projects in planning, managing, and controlling the development process of medium- to large-scale software projects. Its purpose is to reduce uncertainties in the budget, personnel, and schedule planning of software development projects. It is based on dynamic models for the software development and maintenance life-cycle process. This dynamic process is composed of a number of time-varying, interacting developmental phases, each characterized by its intended functions and requirements. System dynamics is used as a modeling methodology. The resulting software life-cycle simulator (SLICS) and the hybrid expert simulation system of which it is a subsystem are described.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Evaluation of SMARTSOY: An expert simulation system for insect pest management

A study to evaluate the prototype soybean insect pest management expert system SMARTSOY was conducted using results from eight south Georgia fields. The state soybean extension entomologist collected insect scouting reports for each field throughout the season and made insect pest management recommendations. These insect and crop scenarios were presented to SMARTSOY for recommendations. The recommendations of SMARTSOY agreed with the recommendations of the entomologist in approximately 80% of the scenarios. Weaknesses in SMARTSOY recommendations involving southern green stink bug damage rates and corn earworm damage rates were determined. A sensitivity analysis was performed to determine how soybean value affected the agreement between the entomologist and SMARTSOY. Agreement was generally better for higher soybean values. Plans for future field testing and expert system implementation are also discussed.