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The purpose of this paper is to present an efficient method for the numerical treatment of robust optimization problems with absolute reliability constraints.

Optimization with anti-optimization based on response surface techniques; polynomial chaos for approximation of the stochastic objective function.

The number of function calls is comparable to that of the corresponding deterministic problem. Thus, the method is well suited for complex technical systems. The performance of the method is demonstrated on an optimal design problem for turbochargers.

The highlights of this paper are: algorithms for robust and deterministic problems show comparable complexity; no derivatives required; good convergence properties because of special set up of optimization problem; application in complex industrial examples.

Elder German grocery shoppers are a growing, heterogeneous, and highly relevant and attractive, but under-researched market segment. In order to understand them and their grocery shopping motivations better and target them efficiently and effectively, the purpose of this paper is to identify dimensions of their shopping motivations and segment them based on these dimensions.

In total, 26 grocery store-choice criteria were identified in a thorough literature review and focus-group interviews with 36 elder German consumers aged 65 and older. In a subsequent survey, the importance of these criteria was rated by 1,288 German shoppers of the same age group. A principal component and cluster analysis were performed to identify dimensions of store-choice criteria and segments of elder German grocery shoppers. Multivariate analysis of variance, analysis of variance and discriminant analysis were used to test for statistically significant differences between the clusters.

Basic quality considerations, shopping experience and social interaction, service and assistance, price consciousness, product orientation, convenient location and quick service and packaging requirements influence the grocery store choice of elder German consumers in decreasing order of variance explained. The cluster analysis revealed indifferent, leisure, convenience, assistance-oriented, no frills, product-oriented and service-oriented elder German shoppers, which differ in their shopping motivations statistically and significantly. These clusters are described and contrasted in detail to derive managerial implications.

This research provides the first store-choice component analysis and cluster analysis for elder German grocery shoppers. This can help food retail to reach this attractive target group more efficiently and effectively and improve the food supply of elder German consumers.

The purpose of this paper is to gain a general holistic view of implications of the growing and highly relevant customer segment of elder consumers for the food demand chain (food retail, production, logistics, and business informatics) in Germany.

This paper takes a holistic demand-chain approach that is based on interviews with 36 German food consumers aged 65-87 and with 50 experts from manufacturing, trade, logistics, and business informatics as well as a survey with 1,288 consumers above 64 years of age and 682 consumers below 65 years of age.

Physical, statistical, psychological, social, and behavioural characteristics of elder German consumers may influence location, services, and layout of food retail, food variety, sizes, packaging, and labelling, food production, transportation, and storage volumes and capacities, as well as facility location, route, and inventory planning. The social function of grocery shopping especially for single consumers, intergenerational products and services, home-delivery services especially to rural areas, as well as decentralisation and regionalisation are expected to gain importance. Logistics and industry 4.0 can facilitate the efficient and effective supply of food.

This research is the first to investigate the needs and wants of elder German food consumers and their implications for the German food demand chain in a more holistic demand-chain approach.

Current online business development redistributes last-mile logistics (LML) from consumer to retailer and producer. This paper identifies how empirical LML research has used and defined logistic performance measures for key grocery industry actors. Using a multi-actor perspective on logistic performance, the authors discuss coordination issues important for optimising LML at system level.

A semi-systematic literature review of 85 publications was conducted to analyse performance measurements used for effectiveness and efficiency, and for which actors.

Few empirical LML studies exist examining coordination between key actors or on system level. Most studies focus on logistic performance measurements for retailers and/or consumers, not producers. Key goals and resource utilisations lack research, including all key actors and system-level coordination.

Current LML performance research implies a risk for sub-optimisation. Through expanding on efficiency and effectiveness interplay at system level and introducing new research perspectives, the review highlights the need to revaluate single-actor, single-measurement studies.

No established scientific guidelines exist for solving LML optimisation in the grocery industry. For managers, it is important to thoroughly consider efficiency and effectiveness in LML execution, coordination and collaboration among key actors, avoiding sub-optimisations for business and sustainability.

The study contributes to current knowledge by reviewing empirical research on LML performance in the grocery sector, showing how previous research disregards the importance of multiple actors and coordination of actors, efficiency and effectiveness.

Data-driven market segmentation is heavily used by academic tourism and hospitality researchers to create knowledge and by data analysts in tourism industry to generate market insights. The stability of market segmentation solutions across repeated calculations is a key quality indicator of a segmentation solution. Yet, stability is typically ignored, risking that the segmentation solution arrived at is random. This study aims to offer an overview of market segmentation analysis and propose a new procedure to increase the stability of market segmentation solutions derived from binary data.

The authors propose a new method – based on two independently proposed algorithms – to increase the stability of market segmentation solutions. They demonstrate the superior performance of the new method using empirical data.

The proposed approach uses k-means as base algorithm and combines the variable selection method proposed by Brusco (2004) with the global stability analysis introduced by Dolnicar and Leisch (2010). This new approach increases the stability of segmentation solutions by simultaneously selecting variables and numbers of segments.

The new approach can be adopted immediately by academic researchers and industry data analysts alike to improve the quality of market segmentation solutions derived from empirical tourist data. Higher quality market segmentation solutions translate into competitive advantage and increased business or destination performance.

The proposed approach is newly developed in this study. It helps industry data analysts and academic researchers to reduce the risk of deriving random segmentation solutions by analyzing the data in a systematic way, then selecting the most stable solution using the segmentation variables contributing to this most stable solution only.

The purpose of this paper is to analyse professionals’ competencies in supply chain management (SCM) in the mid-sized supermarket sector in Brazil as a way of broadening the understanding of the importance and the use of competencies in business development.

The survey was conducted with 60 managers from 34 companies in the mid-sized supermarket sector in the metropolitan region of Natal, Brazil. The managers evaluated the importance and use of a set of 24 general and specific competencies related to SCM. The gaps between importance and use were identified and analysed.

The results showed that the level of use was below the level of importance for all competencies, and the general competencies somehow received more attention than specific competencies in the development and execution of SCM activities. Moreover, the overall average of the gaps between levels of use and importance calculated for the general competencies was less than the general average of the gaps calculated for the specific skills.

The research was carried out with a sample of mid-sized supermarkets in a particular region. Therefore, it is recommended that the research be extended to other contexts and supermarket companies of other sizes.

The calculated gaps between managers’ expectations or attributed importance and the perceived levels of competence use in supermarket organisations revealed important lines of action for correcting the course in human resources policy.

The present paper elaborated on an opportunities matrix, gaps × importance, showing how managers can set priorities to fill competence gaps and improve the companies’ human resources. Besides, it compares levels of importance and uses for two groups of competencies, general and specific related to SCM.

The authors assessed the certification of street food retailers in Ghana in terms of awareness, training, willingness to be certified, determinants, agreement with certification requirements and impacts on performance.

Primary data was sourced from 200 street food retailers. Descriptive statistics, Likert scale, mean comparison test, heteroskedastic probit, inverse-probability-weighted regression adjustment (IPWRA), inverse probability weights (IPW) and augmented inverse-probability weighting (AIPW) were applied.

Most uncertified retailers were willing to be certified. Awareness about certification was high. Most of the certified retailers had been trained on certification, while most uncertified retailers had not been trained. Being a female, being educated, being a migrant vendor, possessing experience in retailing, training in certification, trust in the local certification process, the amount spent in preparing food and the number of customers are crucial variables that increase the probability of being certified among street food vendors. Street food retailers agreed to all the requirements for certification. Certification boosts the performance of street food retailers in terms of the number of customers and contracts received. Training on certification is recommended for street food retailers.

The limitation of this study is mainly due to the type of food retailers selected. Street food vending in Ghana is done among those who cook food for selling, those who sell processed products such as drinks and those who sell vegetables and other uncooked agriproducts. Meanwhile, the authors selected unorganised retailers who primarily cook local and regional dishes for sale in this study. Thus, the study did not include organised food retailers such as restaurants. Therefore, generalising the study results for street food vendors should be made with caution.

Several studies have been conducted on street food retailing across the globe on knowledge of food-safety practices, risk practices, bacterial contamination of street retailing food, toxicological hazards of street foods and compliance with technical and hygienic requirements by street food retailers, among others. However, empirical studies on the certification/licensing of street food retailers and its impact have been given little attention. As a result, this study investigates the certification of street food retailers and its impacts on retailers' performance in Ghana.

The purpose of this paper is to examine Czech traditions of outdoor games and sports, turistika activities and education in nature programmes, which have continued to develop during periods of oppression and provided opportunities to preserve the Czech culture.

A review of the historical, cultural and political context of education in nature traditions in Czech was proposed.

Late 19th century organisations such as the Turistický klub and Sokol were instrumental in developing a range of indigenous turistika activities involving active movement. The early 20th century influences were the Czech scouting movement, summer camps and Woodcraft. Charles University provided the first tertiary outdoor educational programmes in Prague in the 1950s. Their foundation course “Turistika and Outdoor Sports” is still compulsory for all students studying physical education and sport. Turistika activities and outdoor sports and games continued to be developed throughout the liberalization of the socialist regime in the 1960s.

Following the Prague Spring in 1968, and under the guise of the Socialist Youth Union organization, new experimental forms of outdoor education emerged.

Since the Velvet Revolution in 1989 organisations have reconnected with Czech outdoor traditions that flourished before 1948 and other organisations have developed education in nature programs. The commercial sphere, which did not exist before 1989, has now been established in the outdoor area. However, traditional participation in turistika activities has been impacted by other external motivations as a broader range of opportunities have become available and accepted, and tourism outside of Czech and Europe has become increasingly popular and accessible.

The originality of this paper is to provide an overview of Czech political and cultural history and how it has shaped people's relationship, particularly children and youth, with the outdoors.