Integrating MRP and finite capacity planning

Traditional production control systems based on the manufacturing resource planning concept do not sufficiently support the planner in solving capacity problems, ignore capacity constraints and assume that lead times are fixed. This leads to problems on the shop floor, that cannot be resolved in the short term. This paper focuses on solving these capacity problems by improving capacity planning at the material requirements planning MRP level through integration of MRP and finite capacity planning. This results in a planning method for simultaneous capacity and material planning. The planning method is based on a new and more accurate primary process model, giving the planning algorithm more flexibility in solving capacity problems. The algorithm is based on advanced scheduling techniques and uses aggregated information, thus combining speed and accuracy. The algorithm is designed to use the available flexibility: alternative routeings, safety stock, and replanning of production orders and requirements. This paper also discusses such related issues as robustness, memory and the role of the human planner.     

A Risk Management Procedure for the Washington State Ferries

The state of Washington operates the largest passenger vessel ferry system in the United States. In part due to the introduction of high-speed ferries, the state of Washington established an independent blue-ribbon panel to assess the adequacy of requirements for passenger and crew safety aboard the Washington state ferries. On July 9, 1998, the Blue Ribbon Panel on Washington State Ferry Safety engaged a consultant team from The George Washington University and Rensselaer Polytechnic Institute/Le Moyne College to assess the adequacy of passenger and crew safety in the Washington state ferry (WSF) system, to evaluate the level of risk present in the WSF system, and to develop recommendations for prioritized risk reduction measures, which, once implemented, can improve the level of safety in the WSF system. The probability of ferry collisions in the WSF system was assessed using a dynamic simulation methodology that extends the scope of available data with expert judgment. The potential consequences of collisions were modeled in order to determine the requirements for onboard and external emergency response procedures and equipment. The methodology was used to evaluate potential risk reduction measures and to make detailed risk management recommendations to the blue-ribbon panel and the Washington State Transportation Commission.     

Putting Ecstasy to Work: Pleasure,Prostitution, and Inequality in the Indonesian Borderlands

This article takes the drug Ecstasy as a commodity located at the center rather than at the margins of social processes, a technology that allows for the temporary engagement with pleasure and displacement of inequality in the context of nightlife and prostitution. It addresses these issues by focusing ethnographic attention on how Indonesian female prostitutes and their Singaporean male clients use Ecstasy in a disco on the Indonesian island of Batam, an export-processing zone located at the border to Singapore. By paying close attention to consumption practices, the article uses Ecstasy as a starting point for illuminating intersections of social mobility and inequality in the context of contemporary forms of transnational capitalism.     

Academic writing as autocommunication – the case of doctoral dissertations on CSR

In this article, we explore the self‐oriented rather than socially‐oriented reasons why a doctoral dissertation in the field of corporate social responsibility (CSR) is written. We base our article on Yuri M. Lotman’s idea on autocommunication which we use as tool in analysing a group interview conducted with six doctoral students studying in the field of CSR. We suggest that autocommunicational aspects might play a much more important role in rationalized Western culture and science than is often realized, and our main thesis is that one essential reason for writing a doctoral dissertation in the field of CSR might be to communicate with oneself and that this even might contain a therapeutic dimension. Implications for students, supervisors and future research are discussed at the end of the article.     

Searching for effective interventions for foster children under stress: a meta‐analysis

Foster children experience a lot of stress because of their life histories and changes in their family circumstances, such as foster care placement. It is important that foster parents recognize the early signs of stress in foster children and learn how to act in a non‐threatening and understanding manner. Family‐based interventions may help in this. In this paper, we report on a meta‐analysis of studies (n= 19) of the effectiveness of such interventions. All studies used a pre‐test/post‐test design. Both problem behaviour in foster children and the parenting skills of foster parents improved by 30%; however, none of the interventions were specifically intended to help young children (<4 years) to cope with stress. The importance of interventions for young foster children is discussed, as well as the necessary elements these interventions should include.     

The front end in non-assembled product development: A multiple case study of mineral- and metal firms

We conceptualize the front end in non-assembled product development to be iterative and experiment-based, consisting of three sub-phases: informal start-up, formal idea-study, and formal pre-study. Although some key activities are shared with the front end activities in assembled product development, literature reviews, anticipating requirements of customers’ production processes, analysis of raw materials, anticipation of scale-up problems, and tests in bench-, pilot plant-, and full scale production represent unique activities. In addition, product concepts were frequently developed in parallel, requiring specification of physical, chemical and structural properties. These findings have implications for increasing the success and quality of front end efforts.     

Psychosocial factors and safety behaviour as predictors of accidental work injuries in farming

Farming is one of the most hazardous occupations in terms of the incidence and seriousness of accidental injuries. Research with other occupational groups has drawn attention to the role of psychosocial factors and stress. Such research needs to be extended to agriculture. Since stress may be a problem faced by farmers, there is a particular need to investigate the associations between farm accidents and work stressors and stress reactions. Using multivariate logistic regression analyses, this study aimed to uncover the best psychosocial predictors of injury, while controlling for exposure-related confounders. From a randomly selected sample of 794 farms, 10% of all farms in Ringkoebing County, Denmark, 393 farmers completed completed weekly accident registration over 12 months. The study sample consisted of 310 farmers who also completed questionnaires on psychosocial factors. Results indicated that farm stressors (including perceived economic problems), stress symptoms, and safety behaviour were predictors of occupational farm accidents. Higher levels of stressors and stress symptoms and poor safety behaviour were all associated with an elevated risk of injury. In the case of stress symptoms, the relation with accidents occurred via an interaction with safety behaviour. The combination of high levels of stress symptoms and poor safety behaviour was associated with a particularly high accident risk.     

Medical care and regional mortality differences within the countries of the European community

This paper addresses the question whether regional mortality differences within developed countries reflect differences in characteristics of medical care service. It adds two new elements to previous studies on this subject: it concentrates on selected ‘avoidable’ causes of death, and it makes parallel analyses for ten EC countries. The results show that levels of medical care supply contribute little to the explanation of regional differences in mortality from the selected conditions. It is concluded that if regional mortality differences are related to health care, factors other than the level of supply are probably involved.     

Disentangling the sources of variation in the survival of the European dipper

The population growth rate of the European dipper has been shown to decrease with winter temperature and population size. We examine here the demographic mechanism for this effect by analysing how these factors affect the survival rate. Using more than 20 years of capture-mark-recapture data (1974-1997) based on more than 4000 marked individuals, we perform analyses using open capture-mark-recapture models. This allowed us to estimate the annual apparent survival rates (probability of surviving and staying on the study site from one year to the next one) and the recapture probabilities. We partitioned the variance of the apparent survival rates into sampling variance and process variance using random effects models, and investigated which variables best accounted for temporal process variation. Adult males and females had similar apparent survival rates, with an average of 0.52 and a coefficient of variation of 40%. Chick apparent survival was lower, averaging 0.06 with a coefficient of variation of 42%. Eighty percent of the variance in apparent survival rates was explained by winter temperature and population size for adults and 48% by winter temperature for chicks. The process variance outweighed the sampling variance both for chick and adult survival rates, which explained that shrunk estimates obtained under random effects models were close to MLE estimates. A large proportion of the annual variation in the apparent survival rate of chicks appears to be explained by inter-year differences in dispersal rates.