An industrial application for total productivity optimization

Abstract. This paper presents four strategies for total productivity optimization of a real-life manufacturing company. These strategies are developed to attain overall growth, cost reduction, upgrading of technical efficiency and management effectiveness. Such strategies have been modelled mathematically by using a nonlinear mathematical programming approach. The model base and the data base used in implementing the strategies can serve as decision support to management for optimizing total productivity.     

Speed in the Internationalization Process of the Firm

While firm internationalization processes have been understood as being dynamic, the dimension of speed has rarely been the main focus of research efforts, which, until a decade ago, focused principally on explaining sequences of entry modes and choices of markets. The emergence of the study of international entrepreneurship has enhanced the role of speed, although this has usually been measured in terms of the time lag between a firm's foundation and its initial international action, with little attempt at defining and explaining the speed of the process once it is under way. This study reviews the concept of speed from an internationalization perspective, describes the multidimensional nature of the concept and sets out the different aspects that link timescales with the types of changes – continuous and discontinuous – that take place during internationalizing processes. The paper concludes with a research agenda as a guide for future work on considering the role of speed in the internationalization process.     

The Economic Efficiency of Sampling Size: The Case of Beef Trim

The economically optimal sample size in a food safety test balances the marginal costs and marginal benefits of increasing the sample size. We provide a method for selecting the sample size when testing beef trim for Escherichia coli O157:H7 that equates the averted costs of recalls and health damages from contaminated meats sold to consumers with the increased costs of testing while allowing for uncertainty about the underlying prevalence rates of contamination. Using simulations, we show that, in most cases, the optimal sample size is larger than the current sample size of 60 and, in some cases, it exceeds 120. Moreover, lots with a lower prevalence rate have a higher expected damage because contamination is more difficult to detect. Our simulations indicate that these lots have a higher optimal sampling rate.     

Quantitative Risk Estimation for a Legionella pneumophila Infection Due to Whirlpool Use

Quantitative microbiological risk assessment was used to quantify the risk associated with the exposure to Legionella pneumophila in a whirlpool. Conceptually, air bubbles ascend to the surface, intercepting Legionella from the traversed water. At the surface the bubble bursts into dominantly noninhalable jet drops and inhalable film drops. Assuming that film drops carry half of the intercepted Legionella, a total of four (95% interval: 1–9) and 4.5×10⁴ (4.4×10⁴ – 4.7×10⁴) cfu/min were estimated to be aerosolized for concentrations of 1 and 1,000 legionellas per liter, respectively. Using a dose‐response model for guinea pigs to represent humans, infection risks for active whirlpool use with 100 cfu/L water for 15 minutes were 0.29 (～0.11–0.48) for susceptible males and 0.22 (～0.06–0.42) for susceptible females. A L. pneumophila concentration of ≥1,000 cfu/L water was estimated to nearly always cause an infection (mean: 0.95; 95% interval: 0.9–～1). Estimated infection risks were time‐dependent, ranging from 0.02 (0–0.11) for 1‐minute exposures to 0.93 (0.86–0.97) for 2‐hour exposures when the L. pneumophila concentration was 100 cfu/L water. Pool water in Dutch bathing establishments should contain <100 cfu Legionella/L water. This study suggests that stricter provisions might be required to assure adequate public health protection.     

Development of an integrated information management model: A case of textile industry

For past two decades many organisations have tried to implement integrated information management systems for better production management based on co-ordination of information and therefore activities of different departments. Although Enterprise Resource Planning systems have been in the market for the past decade, many industries find it difficult to implement such systems due to the amount of work involved in streamlining the documentation, customisation and of high costs reported in implementation. An attempt is made through this paper to propose an integrated model, which can be easily understood by production personnel, with specific emphasis on the textile sector.     

On vendor part delivery dates in a stochastic assembly system

This paper describes the development of a model for the determination of optimal mean part delivery dates in a stochastic assembly system for the objective of minimizing the expected cost of subassembly and part inventory. Parts are assembled at each station to a subassembly. The part delivery and processing times at assembly stations follow known probability distributions. An approximate solution technique based on the optimization of individual stations in isolation is developed. The approximation applies a correction factor, as a function of the variability in part delivery and processing time, cost parameters and number of stations, to the decisions from the single station solutions to compensate for interdependence between stations. Results indicate that this is an effective approach and yields good near-optimal solutions with very little computational effort. Insights regarding the effect of the type of distribution used, random processing times, variance of the distribution used and cost parameter values on part delivery dates are also reported.     

Modular design of integrated databases in production management systems

Abstract

Complexity is a serious problem with respect to the application of information technology in the field of production management. This paper presents an overview of the more fundamental problems encountered and proposes a solution for some of those problems in the form of modular decomposition of the conceptual database structure. It is argued that the complexity of information systems is closely connected to the complexity of the organization. Therefore a condition for the realization of integrated information systems for production management is a simplification of the organizational structure by way of defunctionalization and the forming of autonomous units.     

New developments in generative BOM processing systems

Abstract

The principle of generative bill-of-material (BOM) processing systems is that different BOMs belonging to different product variants can be represented by a single, so-called source BOM. The BOM processing systems comprise additional data structures which hold information on the relationships between product characteristics of parent product variants and component product variants, and on the relationships between characteristics of a parent product variant and its BOM data. These relationships allow the automatic generation of the individual BOM of each represented product variant. There are several alternative ways of implementing a generative BOM processing system. The oldest concept known is the variant BOM concept. This concept provides a relatively simple solution to deal with large varieties of final product variants. However the concept has a number of drawbacks such as the representation of product variety at lower levels in the product structure and data redundancy which hampers data maintenance. In this paper an improved concept for generative BOM processing systems is introduced and described: the generic BOM concept. The generic BOM concept does not focus on representing final product variants only, but takes a broader view towards representing any range of product variants at any level in the product structure. This starting point solves a number of draw-backs implied by the variant BOM concept but it also requires new definitions of BOM relationships and the introduction of new data structures to support the generation of individual BOMs.     

Going global: professional mobility and concerns for LGBT workers

The world of work has regularized the practice of people moving from one country to another to accept job assignments. Travel and relocation are stress-laden endeavours. For LGBT people, the risks can be more complicated than they are for heterosexuals. This article explores particular challenges that LGBT people face when they travel and relocate for business, both domestically and internationally. The article is contextualized with a literature review on sexual minorities and workplace issues, and uses auto-ethnographic stories of three of the authors’ lived experiences as sexual minorities relocating for professional reasons in order to examine issues related to LGBT relocation. These issues include legal, social, cultural and familial considerations. Implications and suggestions for human resource developers are presented, which include acquiring awareness around the psychological and physiological reactions to new and diverse ecologies, or ‘eco-shocks’.     

A Profitability Evaluation of America's Best Hospitals, 2000–2008

Each year U.S. News and World Report evaluates more than 5,000 U.S. hospitals, of which approximately 3% are considered the best hospitals in America, and hospital profitability has emerged as a business objective for these hospitals. This study investigates the profitability performance of the best (highest quality) hospitals in the United States. A 9‐year longitudinal investigation of profitability for the best hospitals in the United States is conducted. The results offer evidence that the primary drivers of hospital profitability are the case mix index and daily bed capacity. In terms of hospital profitability, there appears to be a tradeoff between these two factors. Finally, caution must be used when ranking U.S. News and World Report Honor Roll hospitals, in terms of profitability and performance.