Walid M. Kobrosly

A fuzzy reasoning database question answering system

Describes a question-answering system based on fuzzy logic. The proposed system provides the capability to assess whether a database contains information pertinent to a subject of interest by evaluating each comment in the database via a fuzzy evaluator that attributes a fuzzy membership value indicating its relationship to the subject. An assessment is provided for the database as a whole regarding its pertinence to the subject of interest, and consequently comments that are considered irrelevant to the subject may be discarded. The system has been developed for the examination of databases that were created during the development of the IBM 4381 computer systems, for bookkeeping purposes, to assess whether such databases contain information pertinent to the functional changes that occurred during the development cycle. The system, however, can be applied with minimal changes to a variety of circumstances, provided that the fundamental assumptions for the development of the membership functions are respected in the new application. Its applicability, without modifications, assuming the same subject of interest, is granted for databases comprising similar characteristics to that of the original database for which the system has been developed. >

On the prediction of computer implementation faults via static error prediction models

Abstract We examine and evaluate a number of static error prediction models to determine their applicability in predicting errors that occur during the development of a computer system. In particular, we consider two different cases to determine the applicability of the models. In the first case, software error prediction models are used as is to predict the errors in the microcode of two computer systems. In the second case, the models are calibrated on a computer system and consequently used to predict a follow-on system. The evaluation is conducted by use of 4,600 source files that comprise the microcode development of the IBM 4381 and the IBM 9370 families of computer systems. Based on our data, the analysis shows that the models examined cannot be used to predict errors in large computer systems. Although in some cases, some models produced acceptable results, the overall performance cannot be considered satisfactory.

Establishing the relevancy of the bookkeeping libraries to the functional testing of computer implementations

We address issues related to the definition of faults, errors and failures and their separability, and attribution to the different development processes of computing systems. In particular, we deal with historical databases, which presumably contain certain data (i.e., test failure data) and describe the methodology that can be used to analyze the database and obtain the pertinent information. The validation method may be of particular importance, especially when information from the database needs to be extrapolated for a purpose other than the one for which the database was developed. Our methodology was used to evaluate the historical data collected during the development of the IBM 4381 and 9370 family of computers, and to extrapolate the faults found during the function testing.

Implementation of an optimal task allocation strategy

The author describes the implementation of a task allocation algorithm for multiprocessing systems, providing a simulation package to allocate tasks among identical processors. The proposed model provides an optimal task-assignment strategy for distributed programs by using the graph theoretical approach proposed by W. Chu et al. (1980). This approach discusses the interconnections between the modules, which are distributed over many processors to take advantage of parallel processing. The simulation package that is used to simulate the task allocation is written in APL. It generates run-times, communication delays, and execution times for the tasks to be distributed. It then optimizes the system execution time and recommends a task allocation scheme based on these values. In addition, the author provides an allocation strategy based on simulation results. In particular, he focuses on the optimal values of the system run-time and communication delay, and subsequently the system execution time.<<ETX>>