Linear and nonlinear shelf space allocation problems with vertical and horizontal bands

Aim/purpose – Shelf space is one of the most important tools for attracting customers’ attention in a retail store. This paper aims to develop a practical shelf space allocation model with visible vertical and horizontal categories. and formulate it in linear and non-linear forms. Design/methodology/approach – The research is mainly based on operational research. Simulation, mathematical optimization, and linear and nonlinear programming methods are mainly used. Special attention is given to the decision variables and constraints. Changing the dimensioning of the decision variables results in an improvement in the formulation of the problem, which in turn allows for obtaining an optimal solution. Findings – A comparison of the developed shelf space allocation models with visible vertical and horizontal categories in linear and nonlinear forms is presented. The computational experiments were performed with the help of CPLEX solver, which shows that the optimal solution of the linear problem formulation was obtained within a couple of seconds. However, a nonlinear form of this problem found the optimal solution only in 19 out of 45 instances. An increase in the time limits slightly improves the performance of the solutions of the nonlinear form. Research implications/limitations – The main implication of research results for science is related to the possibility of determining an optimal solution to the initially formulated nonlinear shelf space allocation problem. The main implication for practice is to take into consideration the practical constraints based on customers’ requirements. The main limitations are the lack of storage conditions and holding time constraints. Originality/value/contribution – The main contribution is related to developing mathematical models that consider simultaneous categorization of products vertically, based on one characteristic, and horizontally, based on another characteristic. Contribution is also related to extending the shelf space allocation theory with the shelf space allocation problem model in relation to four sets of constraints: shelf constraints, product constraints, orientation constraints, and band constraints

A Linearisation Approach to Solving a Non-linear Shelf Space Allocation Problem with Multi-oriented Capping in Retail Store and Distribution Centre

Shelf space is one of the essential resources in logistic decisions. Order picking is the most time-consuming and labourintensive of the distribution processes in distribution centres. Current research investigates the allocation of shelf space on a rack in a distribution centre and a retail store. The retail store, as well as the distribution centre, offers a large number of shelf storage locations. In this research, multi-orientated capping as a product of the rack allocation method is investigated. Capping allows additional product items to be placed on the rack. We show the linearisation technique with the help of which the models with capping could be linearised and, therefore, an optimal solution could be obtained. The computational experiments compare the quality of results obtained by non-linear and linear models. The proposed technique does not increase the complexity of the initial non-linear problem. (original abstract

Sensory quality of top-fermented light beers brewed homey and commercially

Jakość piwa jest kluczowym kryterium, które odgrywa coraz większą rolę na rynku browarniczym. Celem pracy było określenie jakości sensorycznej piw jasnych górnej fermentacji w stylu American Pale Ale (APA) i Witbier zarówno produkcji domowej (odpowiednio DA i DW), jak i komercyjnej pochodzącej z małych browarów rzemieślniczych (odpowiednio RA i RW) i dużych koncernów (odpowiednio KA i KW). Ocenę sensoryczną cech (zapach, smak, smakowitość, nasycenie CO2 oraz goryczka) metodą 5-punktową przeprowadzono z udziałem zespołu 15 ekspertów. Jakość sensoryczna piwa domowego APA charakteryzowała się porównywalną jakością do piw komercyjnych RA i KA. Ponadto piwo DA uzyskało statystycznie istotnie (p≤0,05) najwyższą ocenę (3,9) za zapach w porównaniu z piwem rzemieślniczym RA (3,2). W stylu Witbier piwo domowe uzyskało porównywalną jakość (3,4), lecz tylko w odniesieniu do piwa KW (3,8). Opracowana receptura piwa DA może stanowić recepturę wyjściową do uzyskania wyrobu o wysokiej jakości.Quality is the most important factor playing an increasingly important role on the brewing market. The aim of the study was the sensory quality evaluation of top-fermented light beers in both American Pale Ale (APA) and Witbier style, produced homey (DA and DW, respectively) and commercially by small craft breweries (RA and RW, respectively) and large breweries (KA and KW, respectively). Sensory analysis was applied with the 5-point scale rating method, by 15-person expert panel. The smell, taste, flavor, CO2 saturation and bitterness were assessed. APA home-made beer was characterized by the same quality as beer from small (RA) and large (KA) breweries. In addition, the smell evaluation of DA was significantly statistically (p≤0.05) the highest (3.9) in comparison with RA craft beer (3.2). In the Witbier style, the home-made beer was comparable quality (3.4), but only to KW beer (3.8). The developed recipe for DA can be the starting recipe to obtain the product of high quality

Non-Commercial Grapevines Hybrids Fruits as a Novel Food of High Antioxidant Activity

Non-commercial hybrid grapevine cultivars, usually used for dessert purposes or as ornamental garden plants, may contain a wealth of bioactive substances and thus can be regarded as highly valuable food resources. Antioxidant properties and selected groups of polyphenolic components in the three fractions of fruits: peel, pulp and juice; of five hybrid grape cultivars grown in Poland—Michigan, Alwood, Minnesota, V68021 and Beta—were analyzed and characterized. The liquid chromatography coupled with tandem mass spectrometry (LC-MS-PDA-Q/TOF and UPLC-PDA), total polyphenols, flavonoids and anthocyanins, and DPPH, ABTS and FRAP were used for evaluation of antioxidant potential qualitatively and quantitatively as well as simple reductive sugars were measured. The antioxidant activity and polyphenols content depend mainly on the grape fruit fraction, while they depend to a lesser extent on the cultivar of the hybrid grapes studied. It was confirmed that grape skins are characterized by high antioxidant activity and their bioactive characteristics are similar to many hybrid grape cultivars grown in southern and Mediterranean regions of Europe. Especially grape skins of Alwood and Beta cultivars were characterized by a particularly high content of polyphenolic compounds, mainly from the flavonoid and anthocyanin group and a low content of simple sugars