Layered supervisory control architecture for reconfigurable automation

The development of control systems and supporting software remains one of the greatest obstacles to the widespread implementation of highly adaptive reconfigurable automation technology. This paper will present the structure of a modular automation control system designed to support rapid reconfiguration and redeployment of automation components. The paper will first present the concept of a layered system architecture and the use of modular automation components to support the construction of a wide variety of automated systems. This layered system architecture is then applied to the proposed modular supervisory control system responsible for configuring and driving automated production resources. Each of the control components comprising this modular control system will be presented.     

Re-positioning the supplier: an SME perspective

As manufactured products become more complex, their design and manufacturing demands more and more resource which is being increasingly shared between the supply/value chain members. Competition is being typified less by firm versus firm and more by supply chain versus supply chain. The final assemblers are simplifying their supply chain to reduce logistics complexity and provide best value to the final customer. To suppliers, particularly SMEs, this gives rise to both opportunities for increasing 'added value', as well as threats of being dropped from rationalized supplier bases. Historically, SMEs have been sandwiched between large customers and suppliers and have always reacted to their superior bargaining power. Now, if the SMEs want to survive and grow, they have to adopt a more proactive stance to re-position themselves in response to these supply chain trends. In this paper, we present a technique for re-positioning the supplier in terms of'physical value added' and competency/practice-based 'differentiation'. We use the proposed approach to see how one supplier has successfully changed his business and another has developed plans to change, in line with the trends in their industry structure.     

Product universality and design for supply chain management

We describe our experience of developing models in which the principles of design for supply chain management (DFCM) have been implemented for new product development at Hewlett-Packard Company (HP). This experience arises from the development of a new product that is scheduled to be released in 1995. A key design decision faced by the product development team was whether to use a universal module or regionally dedicated modules to satisfy global market requirements. We describe a wide range of factors—including manufacturing and logistics costs—that could be used to support the design decision; these factors associated with product and process design contribute to tolal supply chain costs. We review the analytical model used to evaluate the cost and service implications of the two design alternatives. Finally, we discuss qualitative considerations that might influence the eventual decisions as well as the lessons learned from this real world experience.     

Hierarchical model to design manufacturing systems applied to a metal-mechanic company

This paper describes the application of a model to design and manage the manufacturing process through an integrated system, using a Hierarchical methodology-by means of different aggregation and disaggregation stages with an appropriate time horizon. The hierarchical model obtained allows interfacing between the master schedule and the schedule of the orders. At each level of the hierarchical model some decisions have to be made in order to design the manufacturing system, but having a model that also takes into consideration the management of the system. To do this it is necessary to use aggregated information concerned with the level at which decisions are made. It is obtained from the database, which contains the information at the highest level of aggregation. This model has been applied to a metal mechanic company, that makes final products such as car washers, etc. The benefits of this approach for the company are addressed in this paper.     

The value of rescheduling functionality within standard MRP packages

One of the basic functions of an MRP system is to issue rescheduling messages that urge the planner tospeed up or slow down open orders. It seems in practice that these messages are not used at all by planners. This is mostly due to the inaccuracy of MRP, that more or less ignores safety time, safety stocks and lotsize flexibility in the calculation of reschedule-in messages. Reschedule-out messages are usually ignored because planners do not see the value of the message. Other reasons for not adhering to rescheduling messages are a lack of maintenance of MRP parameters or simply the wrong use of the MRP function. In the future, MRP rescheduling functionality will be used even less than today, due to the changing role of MRP within the planning framework. With the uprise of finite capacity scheduling packages, MRP is being pushed one level upward in the planning hierarchy. This means that rescheduling functionalities for the short term will become completely obsolete in MRP systems.     

Measuring Sharedness of Team-Related Knowledge: Design and Validation of a Shared Mental Model Instrument

Many researchers have explored how people share and construct similar mental models in teams. They have claimed that successful team performance depends on a shared mental model of team members about task, team, equipment and situation. Most of the literature has illustrated simplified relationships between a team's mental model and their performance without a valid instrument addressing the confined and relevant constructs of a shared mental model. This paper describes the instrument development steps and the conceptual framework for factors associated with shared mental models. After development and refinement, the instrument was finalized for use to measure team-related knowledge. The final instrument consists of 42 items that are linked to the five emergent factors of shared mental models including general task and team knowledge, general task and communication skills, attitude toward teammates and task, team dynamics and interactions, and team resources and working environment.     

The perceptions of human resource development professionals in Taiwan regarding their working relationships with subject matter experts (SMEs) during the training design process

While the literature supports the importance of establishing a relationship between designers and subject matter experts (SMEs) in the training design process, this approach is not followed in all global practices. The purpose of this study was to identify the perceptions of human resource development professionals in Taiwan regarding their working relationships with SMEs. The respondents of the study were HRD professionals who worked in high-tech companies located in a science park in Taiwan. The study found that a significant relationship exists between the ability to work with SMEs and current ability in the training design process among HRD professionals who had worked with SMEs. This study provides implications for the professional development of HRD practitioners and HRD practice in Taiwan companies. Cross-cultural issues are discussed to explain inconsistencies between the results and US-based perspectives on the training design process.     

Relations between stressors and group perceptions: Main and mediating effects

Most orgnizations these days utilize groups for the performance of at least some tasks. There is therefore a need to examine the relationthip between job stressors and group functioning. Until now it has been proposed that employees who perceive high levels of stress in their jobs will have negative perceptions of the groups in which they work, in the form of reduced altruism and collective efficacy. They may also have higher levels of psychological strain. This study examined relations between job-related stressors and group perceptions (collective efficacy 3rd the prevalence of altruistic behaviour) in a sample of 2403 mililitary personnel, comprising 31 companies in two US Anny combat brigades. We also examined whether group perceptions mediated the relationship between stressors and both job satisfaction and subjective well-being. Results indicated that stressors were negatively associated with measures of group perceptions, and both job satisfiction and well-being. Furthermore, mediated regression analyses suggested that relations between interpersonal conflict and both job satitfaction and well-being were partially mediated by both group perception measures. These finding suggest that work-related stressors may negatively impact on group functioning, which may lead to employee strains. Implications of these finding are discussed, and suggestions are made for future research.     

Psychometric and Demographic Predictors of the Perceived Risk of Terrorist Threats and the Willingness to Pay for Terrorism Risk Management Programs

A 2009 national telephone survey of 924 U.S. adults assessed perceptions of terrorism and homeland security issues. Respondents rated severity of effects, level of understanding, number affected, and likelihood of four terrorist threats: poisoned water supply; explosion of a small nuclear device in a major U.S. city; an airplane attack similar to 9/11; and explosion of a bomb in a building, train, subway, or highway. Respondents rated perceived risk and willingness to pay (WTP) for dealing with each threat. Demographic, attitudinal, and party affiliation data were collected. Respondents rated bomb as highest in perceived risk but gave the highest WTP ratings to nuclear device. For both perceived risk and WTP, psychometric variables were far stronger predictors than were demographic ones. OLS regression analyses using both types of variables to predict perceived risk found only two significant demographic predictors for any threat—Democrat (a negative predictor for bomb) and white male (a significant positive predictor for airline attack). In contrast, among psychometric variables, severity, number affected, and likelihood were predictors of all four threats and level of understanding was a predictor for one. For WTP, education was a negative predictor for three threats; no other demographic variables were significant predictors for any threat. Among psychometric variables, perceived risk and number affected were positive predictors of WTP for all four threats; severity and likelihood were predictors for three; level of understanding was a significant predictor for two.