Cynthia S. McCahon

FUZZY JOB SEQUENCING FOR A FLOW SHOP

Abstract In job sequencing for a flow shop, processing times are frequently not known exactly and only estimated intervals are given. Fuzzy numbers are ideally suited to represent these intervals. In this work, the Campbell, Dudek and Smith (CDS) job sequencing algorithm is modified to accept trapezoidal fuzzy processing times. Deterministic sequences result, but the sequence performance measurements of makespan and job mean flow time are fuzzy, having been calculated using fuzzy arithmetic. The use of possibility theory and the fuzzy integral enables the schedular to meaningfully interpret these fuzzy results. Deterministic approximations to this fuzzy approach are also investigated.

Using PERT as an approximation of fuzzy project-network analysis

The use of the project evaluation and review technique (PERT) as an approximation of fuzzy project network analysis (FPNA) when the activity times are represented by normalized triangular fuzzy numbers is discussed. Thirty-two networks in various combinations of activity width, activity symmetry, and path completion time disparity were analyzed using both FPNA and PERT. The differences in the expected project completion time, identification of critical activities, amount of activity slack, and the possibility of meeting certain project completion times are investigated. Results indicate that PERT performs well when approximating the expected project completion time, but is prone to large errors when identifying the critical activity set, approximating the amount of activity slack, and estimating the possibility of meeting certain project completion times. >

Strategic information systems and competitiveness: are firms ready for an IST-driven competitive challenge?

Abstract Strategic planning for information systems technology (IST) and its use for competitive advantage have been discussed for some time. However, such research focuses on the planning method and experience of firms that have been successful in their efforts to use IST for competitive advantage. Not much attention has been paid to less successful organizations and to what they are doing to prepare themselves for IST-driven competition. This paper presents a study conducted among small-to-medium size firms showing that a large fraction of these businesses place surprisingly little emphasis on planning for information systems (IS) and these business have a rather low level of awareness of the potential impact of IS planning on competitiveness. These results point to the fact that organizations need help in becoming more proactive in linking IS planning to their competitive strategy.

Service orientation for contact employees in Korean casual-dining restaurants

Abstract The purposes of this study were to validate Groves’ (Perceived service orientation of restaurant employees, unpublished doctoral dissertation, Kansas State University, Manhattan, KS, 1992) restaurant service orientation scale, to examine contact employees’ service orientation in Korean casual-dining restaurants, and to investigate the effect of employee characteristic variables on service orientation. Self-administered questionnaires were distributed to waitpersons and bartenders working for a casual-dining chain in Seoul, Korea. Factor analysis indicated that Groves’ scale had four dimensions (organizational support, customer focus, service under pressure, and prior customer relationship) rather than three. The additional factor of prior customer relationship was determined to be a subdimension of the customer-focus factor. Age, gender, marriage, and education did not have significant impacts on service orientation. However, employees with a longer length of service and those in supervisory positions displayed a higher degree of service orientation. Lastly, employees in each unit of the chain displayed significant differences in service orientation.

Total quality management: are information systems managers ready?

Abstract The results of an empirical survey of information systems (IS) managers indicated that 41% understood the basic philosophy of Total Quality Management (TQM) fairly well. Furthermore, the IS managers typically indicated they thought most of the concepts/tools commonly associated with TQM would be useful to both the organization and the IS function. IS managers currently involved in implementing TQM reported their IS function had achieved the following benefits: improved customer satisfaction, enhanced quality of products and services delivered to the customer, and increased flexibility in meeting customer demands. It was also reported, however, that these benefits typically were not achieved until three-to-five years after TQM initiation.

Foodservice Forecasting Using Simple Mathematical Models

The purpose of this study was to develop, test and evaluate simple math ematical time series forecasting models to predict covers in a commercial foodservice environment. Total covers were selected as the focus of this research because they have been identified as the most common forecast numbers for food sales forecasts within hotel food and beverage operations (Schmidgall, 1989). Key Words: Forecasting, foodservice, mathematical (time series) models, hospitality management.

Foodservice forecasting: differences in selection of simple mathematical models based on short-term and long-term data sets.

This study developed and evaluated mathematical (time-series) forecasting models to predict restaurant covers. The purpose of the study was to determine if model selection would differ for short-term and long-term data sets. In both the short- term and long-term studies, deseasonalized data modeled best. Therefore, daily seasonal differences account for a large portion of the demand variance, and the effect should be included in the forecasting model.

Stability of Inbound Tourism Demand Models for Indonesia and Malaysia: The Pre-and Postformation of Tourism Development Organizations

The purpose of this study was to examine the stability of inbound tourism demand models for Indonesia and Malaysia as a function of increasing government intervention in tourism. Specifically, it investigated the differences in the estimated model parameters before and after formation of tourism development organizations at each destination. The major determinants included in the demand model were income, price, and time trend. The Wald test was applied to examine the possibility of a structural change in the tourism demand between the pre-and postorganization formation periods. The results support the hypothesis, thus important marketing implications for the tourism industries in Indonesia and Malaysia were discussed.

The impact of training technique on the difficulty of quality improvement problem solving

A questionnaire surveying the type of training technique used (lecture, workshop, videotape, role playing, self tutorial (workbook) and self‐tutorial (computer)) for each of the seven steps in the quality improvement problem‐solving process was sent to 180 training directors in firms stating their participation in a quality improvement strategy. The training directors were then queried on the degree of difficulty experienced in executing each of the problem‐solving process steps. Evaluating the solution and final evaluation were shown to be the significantly most difficult steps to execute, and forming a team and identifying the problem were shown to be the least difficult steps; but the level of difficulty was not found to be related to the training technique used.

A Multiple Attribute Evaluation of Bayesian Availability Estimators

Three system availability estimation methods, maximum likelihood, traditional Bayes, and Brenders Bayes were used to obtain estimates for two exponentially distributed data sets. From the simulation results, a best estimation method was chosen through the use of five multiple attribute decision making (MADM) techniques: dominance, simple additive weighting, linear assignment, ELECTRE, and TOPSIS. In terms of the five criteria which are: closeness to steady state, variability between samples, computer execution time, ease of programming, and ease of understanding; and their importance (weight) on the final decision, Brenders Bayes estimation was superior to the other two.