A proposal for CAD/CAM interface with expert systems

In the computer-integrated manufacturing (CIM) environment, the key technologies, CAD and CAM, should be fully integrated with high operability. It is claimed, however, that CAD and CAM have so far been developed independently. Although much effort has been made to integrate CAD and CAM, this reality is far from completion.

Therefore, to establish a CAD/CAM interface with higher integration, the concept of a computer-aided drafting procedure with expert systems has been proposed on the basis of analysis of the information explicitly and implicity described on the part drawing, and also of the required knowledge of the designer to produce the part drawing. The CAD/CAM interface proposed here is available for producing not only the part drawing but also the process plan for the corresponding part, by effectively utilizing the knowledge of the expert. A prototype CAD/CAM interface deals with axi-symmetrical rotational parts implemented on a workstation.     

Evaluating expert systems: a review of applicable approaches

This paper surveys various approaches for evaluating expert systems. More specifically, we categorize the applicable methods found in the literature as being qualitative, quantitative or a hybrid. The more seminal of these methods are described. The review is primarily intended for an audience of researchers and practitioners interested in understanding the scope and limitation of methods within each of the three approaches.     

Automating manual reward systems

The introduction of Personal Computers has enabled Industrial Engineers to automate many aspects of their responsibilities, thus becoming significantly more productive. One aspect which clearly benefits from automation is the creation, implementation, and periodic maintenance of Pay-for-Performance Reward Systems. However, selecting the correct software package is not easy. Industrial Engineers currently have a variety of fully automated software packages to choose from which can range from $2,000 – $100,000. The initial cost alone may make it difficult to Justify for a small plant. Furthermore, if you have a variety of reward systems (Gainsharing - Small Group - One for One) finding a single program to handle all of them may be impossible.

This was a problem Norton Company faced five years ago. We are a fortune 500 company with manufacturing plants located throughout the world, using a variety of reward systems. To remain cost competitive in all aspects of our business, we had to find a way to reduce the on-going maintenance costs of our incentive systems.

Investigating alternatives uncovered a low cost, flexible solution to our problem. The use of off-the-shelf spreadsheet and data base software enabled us to fully automate all aspects of our reward systems.     

Automating cost estimating systems

Interest in Cost Estimating Systems (CES) has grown rapidly in the last few years. The availability, flexibility, speed, and accuracy of micro-computers have provided the impetus for automation of many indirect activities.

Central to the successful automation of the cost estimating function is the relative ease with which the user can customize the application software to a unique set of materials, machines, and methods of the organization. Once customized to his particular application, cost estimating software must be easily adaptable to future business changes as well as changes in the cost estimating technology itself.

This paper describes the development of a CES which provides a highly productive and flexible approach to user customization. The paper includes an explanation of the system's extensive data and program structure. It is capable of accommodating future technological changes resulting from the introduction of engineering work centers with CIM capabilities. The paper concludes with an illustration of its application to a highly diversified aerospace firm.     

Automating the evaluation of urban roadside drainage systems using mobile lidar data

Roadside channel systems are critical for the management of stormwater runoff and the protection of the structural integrity of roads; and thus, require systematic evaluation and maintenance. However, the evaluation of these systems remains ad hoc due to the lack of efficient inspection methods. This paper contributes to filling this gap by providing an automated process for the inspection and evaluation of roadside channel systems using data obtained from mobile lidar (Light Detection and Ranging) scanners. The Cloth Simulation Filtering algorithm was employed to split lidar point clouds into bare earth and object datasets, and then compute six key attributes of roadside channels based on the bare earth dataset. The six attributes are: channel depth, bottom width, side slope, longitudinal slope, and length and density of subsurface pipes and culverts. To test and demonstrate the new automated process, it was applied to six street sections in the City of Houston, Texas. The computed attributes were compared to the design and maintenance guidelines set by the City of Houston and Harris County. The evaluation results indicate that every channel examined in this study has its own condition issues and improvement needs. While no channel section in this study was in full compliance with the guidelines, no channel was utterly incompatible either. The results show that the developed automated process can effectively and efficiently evaluate roadside channels, providing an alternative to conventional manual inspection methods. Future work could use the output of the developed method to assess the risk of localized flooding and inform both the municipal government and property owners about effective mitigation measures.     

Hybrid expert systems: A survey of current approaches and applications

This paper is a statistical analysis of hybrid expert system approaches and their applications but more specifically connectionist and neuro-fuzzy system oriented articles are considered. The current survey of hybrid expert systems is based on the classification of articles from 1988 to 2010. Present analysis includes 91 articles from related academic journals, conference proceedings and literature reviews. Our results show an increase in the number of recent publications which is an indication of gaining popularity on the part of hybrid expert systems. This increase in the articles is mainly in neuro-fuzzy and rough neural expert systems’ areas. We also observe that many new industrial applications are developed using hybrid expert systems recently.     

Performance evaluation of medical expert systems using ROC curves

This paper presents a performance evaluation of the diagnostic accuracy of the medical expert system CADIAG-2/PANCREAS. The study included 47 clinical cases from a university hospital with 51 diagnosis of pancreatic diseases (four patients had two pancreatic diseases). As gold standard, the histologically or clinically confirmed diagnoses were assumed. Performance was studied along three lines: (a) each case was evaluated twice, first, by restricting patient data to history, physical examination, and basic laboratory tests and, second, by utilizing the complete set of data including also special laboratory tests. US. X ray, CT-scan, ECG, and biopsy, if available: (b) considering CADIAG-2's hypotheses generation, each evaluation series was also carried out twice, first, by testing whether the gold standard was the first diagnosis in the ranked list of hypothesis and, second, whether the gold standard was among the hypotheses: (c) receiver operating characteristic (ROC) curves were determined by varying an internal threshold which determined the extent of CADIAG-2's diagnostic hypotheses generation. The evaluation showed that CADIAG-2's initial list of diagnostic hypotheses, based on patient history, physical examination, and basic laboratory tests usually has already included the gold standard diagnosis and thus an application of CADIAG-2 at a very early stage of the diagnostic process seems achievable. Moreover, it turned out that given the complete set of patient's medical data the gold standard is usually ranked at the first place in the list of hypotheses. except for patients with chronic diseases where only unspecific findings are available. The last test series showed that ROC curves do not only allow optimal adjustment of the expert system's internal ad hoc decision criteria such as thresholds, weights, and scores but also provide a basis for better comparing the performance of different medical expert systems.     

Auditor evidence evaluation: expert systems as credible sources

Seventy-four experienced auditors from four Big-6 public accounting firms participated in a study of the effect of expert system use by subordinate auditors on superiors' decisions. Superiors were provided with information about a subordinate's decision and were told that the subordinate had or had not used an expert system. Superiors reported higher belief likelihoods and agreed more frequently with conclusions provided by subordinates who were expert system users, even when those conclusions were wrong. However, superiors' confidence in their own decisions was not affected by subordinate's use of an expert system.     

An evaluation of expert systems for software engineering management

The development of four separate, prototype expert systems to aid in software engineering management is described. Given the values for certain metrics, these systems provide interpretations which explain any abnormal patterns of these values during the development of a software project. The four expert systems which solve the same problem, were built using two different approaches to knowledge acquisition, a bottom-up approach and a top-down approach and two different expert system methods, rule-based deduction and frame-based abduction. In a comparison to see which methods might better suit the needs of this field, it was found that the bottom-up approach led to better results that did the top-down approach, and the rule-based deduction systems using simple rules provided more complete and correct solutions than did the frame-based abduction systems     

Automated test generation and evaluation for real-time expert systems

This paper describes a method for automated test generation and evaluation for real-time expert systems. This method supports dynamic testing, where test inputs are generated randomly within the constraints specified by a Test Specification Language. This allows the discovery of “unintended functionalities,” which may not be possible either through static testing or expert-supplied test cases. Automated test generation also allows rapid regeneration of test suites as the system evolves through various prototypes and versions. the Test Specification Language provides constructs for dealing with real-time constraints. Sample specifications and results implemented within the Activation Framework software development tool are also described. © 1994 John Wiley & Sons, Inc.     

A survey of evaluation techniques used for expert systems in telecommunications

Hardware and software used within the telecommunications industry must combine great complexity with high reliability. Production and maintenance of communications equipment requires many different kinds of human expertise. There is growing interest in the potential of expert systems to assist, or perhaps to replace, human experts. It is important to ensure that the expert systems are reliable and accurate; consequently, they must be evaluated. We review published experience with expert systems in the telecommunications industry and we propose some principles that we feel could usefully be adopted for their evaluation.     

A theoretic framework for intelligent expert systems in medical encounter evaluation

Abstract: This paper describes a novel approach to implementation of a medical diagnosis expert system that can assist physicians with their daily practices. Differential artificial intelligence techniques are incorporated into a multi-stage expert system to best represent the various phases of the patient diagnosis process. A weighted scoring system is used to represent the subjective analysis stage, while a rule-based fuzzy expert system is employed to both interpret laboratory tests and imaging findings and suggest the final diagnosis. A model of various patient flow scenarios is presented to demonstrate the functionality of the proposed expert system. An actual example of patient walkthrough is used to demonstrate various computation steps from recording the patient chief complaint to arriving at the final diagnosis. It is shown that the conclusion arrived at by using the proposed system is consistent with a common diagnosis of a third party specialist who is asked to evaluate the performance of the system.     

Formative evaluation in the development and validation of expert systems in education

Researchers developing and validating educational products often expect the same field-test activities to provide information on product improvement and product effectiveness. For effective and economical use of resources, these two goals, product improvement and product validation, must be stressed at different times and with different tools and strategies. This article identifies the difference in procedures and outcome between formative and summative evaluation practices and relates these practices to the development and validation of expert systems in education.     

Development of a fuzzy decision model for manufacturability evaluation

A manufacturability evaluation decision model is formulated and analyzed based on fuzzy logic and multiple attribute decision-making under the concurrent engineering environment. The study emphasizes on the treatment of the linguistic and vagueness at the early product development stage. The study also considers the function integration of the total life cycle of a product. Hence, the integrated decision model covers the multi-level, multi-goal requirements of the products. Multiple criteria such as the goal space, the decision space, the function space, the development (i.e., product & process design) space, and the activity space, are then applied under different analysis of decision-making methods. For instances, the fuzzy multiple attribute decision-making (FMADM) combined with activity-based costing (ABC) can be used in the activity decision space. The fuzzy logic decision model can be applied in the goal decision space. The results of this study point out the importance of early decision making capability. An example of a high-pressure vessel is provided to demonstrate the proposed model for evaluating the manufacturability.     

Statistical expert systems

Abstract: Two types of expert system which involve statistical expertise are statistical consulting programs and programs which find patterns in databases. Consulting programs can now be built quickly using programming tools. Most expert systems include mechanisms for reasoning under uncertainty. Methods under investigation include fuzzy logic, Dempster-Shafer theory, Bayesian analysis and various ad hoc methods. Learning systems use statistics to infer inductive rules, and statistical reasoning can also be used to evaluate the performance of expert systems. The use of a prototype statistical expert system, XSAMPLE, is demonstrated, as a system to handle a consulting session with a statistically moderately advanced user.     

Internet-based expert systems

The Internet offers a large potential for delivery of various information-based services, including the services of intelligent applications. As the availability of the Internet has grown, its value as a medium for the delivery of expert systems in particular has increased. There are now a large number of expert systems available on the Internet, including applications in industry, medicine, science and government. Though the Internet provides several advantages for expert system development, it also presents some special problems. These advantages and disadvantages are explored in more detail in this paper. The paper also presents a review of several Internet-based expert systems with a representative sample of publicly available applications, and a discussion of typical tools for developing Internet-based expert systems. A case study of an Internet-based expert system is presented as well.     

Evaluating expert systems

Abstract: Evaluation is crucial for improving expert system design and performance. This paper stresses the need for considering system evaluation throughout the development process. It highlights the importance of evaluating system usability and discusses key usability issues. A number of basic evaluation methods are described, including interviews, questionnaires, observation, system logging, user diaries, laboratory experiments and field trials. Finally, the paper looks at evaluating systems within organisations, and assessing other long term effects of expert systems.