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The purpose of this paper is to analyze more than three decades of theory testing published in leading operations management (OM) journals.

This piece examines the amount of theory testing, the extent to which theories are tested multiple times, and the disciplinary origins of the theories that are tested.

The analysis revealed that empirical OM researchers have increasingly responded to demands for more theory-driven knowledge over time. OM researchers are developing and using a wide array of domestic theories to understand empirical data. The examination also revealed a substantial focus on theory borrowed from other scientific fields.

The findings here suggest that OM is clearly a maturing discipline. As the discipline matures, it is important to consider to what extent borrowed theories and frameworks can offer value to OM. A preliminary vetting model is advanced in order to critically assess foreign theory. It is hoped that future screening promotes only the most useful non-domestic theory, thereby ensuring sufficient journal space for domestic theory and resulting in effective solutions to the pressing, practical problems of the OM field.

The purpose of this paper is to investigate the possibility to construct tissue-engineered bone repair scaffolds with pore size distributions using rapid prototyping techniques.

The fabrication of porous scaffolds with complex porous architectures represents a major challenge in tissue engineering and the design aspects to mimic complex pore shape as well as spatial distribution of pore sizes of natural hard tissue remain unexplored. In this context, this work aims to evaluate the three-dimensional printing process to study its potential for scaffold fabrication as well as some innovative design of homogeneously porous or gradient porous scaffolds is described and such design has wider implication in the field of bone tissue engineering.

The present work discusses biomedically relevant various design strategies with spatial/radial gradient in pore sizes as well as with different pore sizes and with different pore geometries.

One of the important implications of the proposed novel design scheme would be the development of porous bioactive/biodegradable composites with gradient pore size, porosity, composition and with spatially distributed biochemical stimuli so that stem cells loaded into scaffolds would develop into complex tissues such as those at the bone–cartilage interface.

The dynamics of drug use and trafficking in Poland have changed dramatically since the early 1990s. These changes include legal definitions of drug use, the actors involved in trafficking, and the types of drugs traversing the country. The Polish police force experienced two significant reforms in the 1990s and drug‐related legislation underwent significant reconstruction in 1997 and 2000, while drug trafficking operations continue to persist by organized criminal groups. The purpose of this study is to qualitatively investigate these police reforms and drug legislation developments since 1990, and empirically analyze the interaction effects of these reforms with drug trafficking arrests in Poland.

Officially reported annual data were tested using multivariate regression analyses.

The findings observed from this exploratory study suggest that both the police reforms and changes in drug‐related legislation positively affected the number of arrests for drug trafficking. Additionally, this study found support for an increase in efficiency of the policing model despite the recent decline in the strength of the police force. Interestingly, the number of police officers in the country had no effect on any of the variables.

Quantitatively, the small number of observations poses limitations on the interpretation of the multivariate regression results. In addition, future research should include additional explanatory variables to achieve a greater comprehensive summary of the interaction effects of policing reforms and drug‐related legislation with drug trafficking arrests.

This paper illustrates the need for accurate and timely national‐level, systematically collected data on drug‐ and police‐related indicators that will allow for more inclusive and comprehensive analyses.

This study is one of the first to empirically examine potential interaction effects of police reform and drug‐related legislation on drug trafficking arrests in Poland.

Vehicle weight reduction represents a viable means of meeting tougher regulatory requirements designed to reduce fuel consumption and control greenhouse gas emissions. This paper aims to present an empirical and comparative analysis of lightweight magnesium materials used to replace conventional steel in passenger vehicles with internal combustion engines. The very low density of magnesium makes it a viable material for lightweighting given that it is lighter than aluminium by one-third and steel by three-fourth.

A structural evaluation case study of the “open access” Wikispeed car was undertaken. This included an assessment of material design characteristics such as bending stiffness, torsional stiffness and crashworthiness to evaluate whether magnesium provides a better alternative to the current usage of aluminium in the automotive industry.

The Wikispeed car had an issue with the rocker beam width/thickness (b/t) ratio, indicating failure in yield instead of buckling. By changing the specified material, Aluminium Alloy 6061-T651 to Magnesium EN-MB10020, it was revealed that vehicle mass could be reduced by an estimated 110 kg, in turn improving the fuel economy by 10 per cent. This, however, would require mechanical performance compromise unless the current design is modified.

This is the first time that a comparative analysis of material substitution has been made on the Wikispeed car. The results of such work will assist in the lowering of harmful greenhouse gas emissions and simultaneously augment fuel economy.

Sets out an exploratory study to give an alternative viewpoint of manufacturing logistics.

Based on causal analysis, the relationship between competitive strategy and manufacturing logistics was explored. Variables, including both positioning and competitive dimensions, in the competitive strategy that interacted with manufacturing logistics were identified. The elements of manufacturing logistics for this study included master production scheduling, capacity requirements planning, material planning, purchasing, and inventory control. A weighted business performance index was used to segregate the sample firms into three groups: high‐, average‐, and low‐performing organizations. For each of the performance group, the causal relationships between strategic elements and the performance of manufacturing logistics were then analyzed.

The results showed a significant relationship between competitive strategy and manufacturing logistics system performance.

Not all the elements in manufacturing logistics may contribute to the logistics performance. The construct of manufacturing logistics depends on a particular set of strategic variables that the organization designs.

Extends the study of manufacturing logistics beyond its boundary through a broader strategic perspective.

The purpose of this paper is to examine the role of creative destruction as mediation between the speed of innovation and competitiveness of food small and medium enterprises (SMEs). Creative destruction that is competence-based and market-based is usually done by incumbent enterprises to create barrier to entry and widen the distance with similar businesses, then the role of creative destruction as a mediation to strengthen the competitiveness is investigated.

To test this, data were collected from 161 SMEs that is the food SME population in Great Malang covering three areas namely Malang Municipality, Malang Regency and Batu Municipality. warp partial least square-structural equation modeling (WarpPLS-SEM) was applied because parameter estimation with WarpPLS-SEM is very efficient because it has greater statistical requirements than other covariant-based methods, which is more likely to deliver results that match the population condition (significant if that is in fact significant in the population).

The pace of innovation development is very important to improve the competitiveness of food SMEs. The idea of innovation is quickly realized and products that enter the market faster have a greater chance to improve competitiveness through profit and productivity. The pace of innovation development enhances the competitiveness of food SMEs. This study proves that competitiveness can be increased once the pace of innovation development is followed by creative destruction. Creative destruction in this case is done through increased competence and maintain the innovations that have been achieved by food SMEs. Increased business competence could be conducted through cost efficiency enhancing product quality and improving worker skill. It is conducted while maintaining the achieved innovation to strengthen the market network customer service and innovation in product packaging. The government’s role is proven not to strengthen the relationship of the pace of innovation development and competitiveness of food SMEs. The role of the government is reflected through credit facilities business licensing promotion marketing and training. These have been carried out by the government. Nevertheless, these activities do not generate widespread impact in strengthening the pace of innovation development to enhance the competitiveness of food SMEs.

The main limitation of this study is that it analyzes processed foods and innovations in general. Future research should investigate one type of processed food based on the typology of innovation so as to provide more effective and efficient recommendations.

This is the first known analysis of innovation speed and creative destruction for SMEs of food sector.

The use of U‐V technology in conformal coating applications has come of age. This paper discusses the material, process, and equipment which recently have been utilised for the conformal coating of printed wiring boards. First is presented a description of the coating material properties, both uncured and in the cured state. Next follows a discussion of the processing scheme, parameters such as time, speed, and U‐V light source requirement. Hardware to enable the coating operation to fit into an automated assembly line is also described. Of special interest will be the employment of masking techniques to prevent coating of certain critical areas. Lastly, typical performance data on the actual product having the U‐V coating are presented. An overall appraisal of the entire U‐V system is included.

One of the main problems, when choosing between preventive or corrective maintenance for the production and maintenance departments in the eight firms studied, is to attempt to establish the state of a particular production system or individual production line. In order to carry out a cost analysis it is imperative to be able to measure how preventive maintenance will both reduce the deterioration of the state of the object and improve the state of the object at the point in time that the maintenance is carried out. This can be explained by the fact that the departments lack methods for measuring and estimating the effects. The model presented in this paper determines whether to schedule preventive maintenance and the model trades off the capital costs of preventive maintenance and the sum of corrective maintenance and down‐time costs based on the production line’s state.

This paper is aimed at comparing cellular manufacturing with focused cellular manufacturing. We define focused cellular manufacturing as a layout scheme that groups components by end‐items and forms cells of machines to fabricate and assemble end‐items. It is not classified as a cellular manufacturing layout since it does not attempt to take advantage of process similarities. It also is not classified as a flow shop since there are no machines dedicated to individual operations and the machines are not arranged in a series. In addition, this research includes batching and assemble times in its criteria which few researchers in this area have done. The results indicate that the focused cellular manufacturing scheme has a batching advantage. This advantage out‐weighed the set‐up time reduction advantage of the cellular manufacturing scheme for average end‐item completion times and average work‐in‐process inventory levels. The cellular manufacturing scheme overcame the batching advantage only when there were small batch sizes or large set‐up time magnitudes.

The purpose of this study is to characterize sintered hydroxyapatite (HA) samples produced by three-dimensional printing (3DP). This study is part of a project concerned with the fabrication of calcium phosphates implants by 3DP. However, before considering a more complex structure, like scaffolds or implants, a thorough knowledge of the role played by the sintering temperature on physical and mechanical the properties of porous HA is necessary.

The characteristics of sintered HA samples have been analyzed by means of x-ray diffraction, scanning electron microscope (SEM) and uniaxial compression tests. The 3DP parameters used to produce the HA samples were those who led to higher accuracy and mechanical stability.

Sintering temperature and powder morphology are critical factors influencing densification behavior, porosity, phase stability, mechanical strength and tangent modulus of the HA samples produced by 3DP. This study allowed us to conclude about the 3DP parameters to be used to produce porous HA specimens with the required integrity and dimensional accuracy, and the optimal post-processing sintering temperature which led to the best results in terms of porosity, microstructure, phase stability of HA and mechanical properties.

This paper provides a method to evaluate the manufacturability of calcium phosphate models produced by 3DP.