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Engineered stone is a material which can be described as an artificial stone. The exemplary application area is sink production. There are very few research projects about this type of material. In fact, most of them are research conducted by the manufacturing company, which are limited to the basic properties of the material. However, knowledge about fracture mechanic of this material may be crucial in terms of usage. The paper aims to discuss this issue.

Analysis of the inside structure was made using an optical microscope as well as SEM. In the paper, methods which can be used to obtain data about fracture behaviour of material are presented. Using eXtended Finite Element Method and experimental data from three-point bending of notched specimens stress intensity factors (SIFs) for I and II load modes were obtained. Finally, a comparison between the fracture initiation angle in the function of the ration of SIFs for I/II load modes and maximum tangential stress hypothesis prediction was presented.

Analysis of the inside structure proves that this type of material has an uneven distribution of particle size. This can follow to void and micronotches formation and, later, to the failure of the material. A method of obtaining stress intensity factors for the discussed type of material and specimens can be successfully applied to other similar material, as proposed in this work. Standard crack angle propagation criteria are not sufficient for this type of material.

There are very few research papers about this type of material. The subject of fracture mechanic is not properly discovered, despite the fact that IT is important in terms of the application area of these materials.

For nowadays construction purposes, it is necessary to define the life cycle of elements with defects. As steels 42CrMo4 and 41Cr4 are typical materials used for elements working under fatigue loading conditions, it is worth to know how they will behave after different heat treatment. Additionally, typical mechanical properties of material (hardness, tensile strength, etc.) are not defining material’s fatigue resistance. Therefore, it is worth to compare, except mechanical properties, microstructure of the samples after heat treatment as well. The paper aims to discuss these issues.

Samples of normalized 42CrMo4 (and 41Cr4) steel were heat treated under three different conditions. All heat treatments were designed in order to change microstructural properties of the material. Fatigue tests were carried out according to ASTM E647-15 standard using compact tension specimens. Later on, based on obtained results, coefficients C and m of Paris’ Law for all specimens were estimated. Similar procedure was performed for 41Cr4 steel after quenching and tempering in different temperatures.

The influence of heat treatment on the fatigue crack growth rates (42CrMo4, 41Cr4 steel) has been confirmed. The higher fatigue crack growth rates were observed for lower tempering temperatures.

This study is associated with influence of microstructural properties of the material on its’ fatigue fracture. The kinetic fatigue fracture diagrams have been constructed. For each type of material (and its heat treatment), the Paris law constants were determined.

The purpose of this paper is to assess the technical state of old and repair steels of Shukhov’s tower elements after operation during ~ 110 and 70 years of the water tower in Nikolaev, basing on their mechanical tests, metallography and fractography investigations.

For their certification, the fractographic and structural features and mechanical properties (hardness, strength, plasticity and impact toughness) were analyzed. Both the steels under consideration were characterized by low values of hardness and brittle fracture resistance. The mechanical characteristics of the old steel are lower compared with the repair one. It cannot be only explained by the quality of metal rolling. Moreover, the plasticity characteristics of both steels, defined in synthetic acid rain environment, are lower than in the air. Using fractography investigation, the operational damages in the bulk metal in the form of the elements of cleavage fracture in the central part of the fracture surfaces of specimens tested at the hydrogenation condition by synthetic acid rain environment were revealed.

The results of this study suggested a degradation of steels’ characteristics caused by the development of scattering damages during their operation. Higher relative elongation of the old steel at lower hardness and impact toughness were also evidenced in that. The metallography and fractography investigations also supported this finding.

This original study aimed at characterizing the microstructural and mechanical degradation of mild steels that was collected from Shukhov’s tower structural elements.

The purpose of this paper is to analyze consumers’ reaction to assortment composition.

This study examines several scenarios: private label (PL)-only assortments; mixed assortments (PL and national brands (NBs)), and in the latter case both small and large assortments. Consumers’ reaction is measured through three dependent variables: store image, PL purchase intention and store-switching intentions. The authors ran a structural equation model (SEM) to analyze the influence of different explanatory aspects (product category involvement, attitude toward PL, value consciousness and assortment variety perception) on consumers’ reactions for each scenario. For this research, the authors carried out an online experiment with a sample of 1,400 individuals from a large panel of consumers.

Consumers react differently to different assortment compositions, giving importance to the differences between the three assortment models analyzed. The results show that the composition of the assortment, either according to its size or its structure, influences consumers’ response in a significant way. The results demonstrate that store image exclusively affects PL purchase intention in PL-only assortments. Only in mixed assortments is there a relationship between the assortment variety perception and store image, product category involvement and PL purchase intention, and both store image and value consciousness are related to store-switching intentions. Store-switching intentions decrease when consumers intend to purchase PL, but strictly in PL-only and large mixed assortments. Finally, value consciousness and variety perception are positively related to PL purchase intentions only in large mixed assortments.

One limitation of this research is that it is restricted to the Spanish context. Second, the methodology is based on an online experiment, with the advantages and disadvantages that this entails. Third, the authors did not differentiate between high- and low-value PL which, if undertaken, could be of interest for observing how brand value affects the management of retail assortments. Finally, the authors did not differentiate regular buyers at these retail chains from those who are not.

The comparison between different assortment compositions helps the authors to draw some very interesting conclusions. The estimation of different consumers’ responses is ideal for providing retailers with recommendations on how to frame their assortment strategies. Thus, the main recommendation of this study for retailers is to look for a “balance” between PL and NBs, i.e., to offer mixed assortments.

Aside from mixed assortments, this study estimates the consequences of assortments that are exclusively PL. The authors proposed and deployed a SEM, so this paper contributes to the retailing field by including multiple dependent variables – store image, PL purchase intention and store-switching intentions. The authors conducted an online experiment containing “real” brands, which is another contribution as it enables consumers’ response to be estimated in a “real” environment.

The authors analyze the relationship between different consumer attitudinal variables and a number of variables related to consumer perception of the store and purchasing behavior, in assortments composed exclusively of private labels (PLs).

The authors developed an experiment based on an online survey to test the hypotheses formulated. The model’s causal relationships are established using structural equations.

The image of stores that only offer their own brand is mainly configured by price consciousness and the attitude toward the private label. The private label purchase intention is strongly influenced by the store image and a favorable attitude toward the brand, and loyalty strategies should be aimed at securing a clear perception of providing real value.

For retailers who only offer their own brands, an assortment with price-competitive PLs is key to the strategy of differentiating them from other retailers. It is reasonable to assume that, if retailers have a favorable image, customers transfer this brand value to their PLs and trust them. Customer loyalty strategies of these retailers should be aimed at ensuring that consumers clearly perceive that their assortment provides real value and that, although it is limited in terms of number of brands, it can meet all their needs.

This research represents a significant contribution to brand management literature because, includes, together with loyalty to the store, its image and the PL purchase intention as consumer response variables. Another differentiating feature is the methodology used. Estimation of the structural equation model permits the simultaneous estimation of the relationships between the variables.

Analizamos la relación entre diferentes variables actitudinales de los consumidores y un número de variables relativas a la percepción de los consumidores con respecto al establecimiento y el comportamiento de compra, todo ello en surtidos compuestos exclusivamente por marcas de distribuidor.

Desarrollamos un experimento online, basado en una encuesta, para testar las hipótesis planteadas. Utilizamos ecuaciones estructurales para determiner las relaciones causales del modelo.

La imagen de los establecimientos que ofrecen exclusivamente su propia marca se configura, principalmente, por la conciencia de precio y por la actitud de los consumidores hacia la marca privada. La intención de compra de la marca de distribuidor está fuertemente influenciada por la imagen del establecimiento y por una actitud favorable hacia dicha marca, por lo que las estrategias de fidelización de clientes deberían estar orientadas a asegurar una clara percepción de proporcionar valor real a los consumidores.

Para los minoristas que ofertan exclusivamente sus propias marcas, un surtido con marcas de distribuidor muy competitivas en precio es fundamental en su estrategia de diferenciación de sus competidores. Además, es razonable suponer que si los minoristas cuentan con una imagen favorable, los consumidores trasladarán este valor de marca a sus propias marcas propias y confiarán en ellas. Las estrategias de fidelización de este tipo de minoristas deberían ir enfocadas a asegurarse de que los consumidores perciben claramente el valor real que aporta su surtido y que, aunque limitado en términos de número de marcas y alternativas, les permite cubrir todas sus necesidades.

Esta investigación supone una significativa contribución a la literatura sobre gestión de marcas al incluir, conjuntamente con la lealtad al establecimiento, su imagen y la intención de compra de la marca de distribuidor como variables respuesta del consumidor. Otro elemento diferenciador es la metodología empleada, ya que la estimación del modelo de ecuaciones estructurales permite la estimación simultánea de las relaciones entre las distintas variables.

There are two fundamental facts about programming languages: there are lots of them; all but a handful are never used beyond the immediate circle of friends of the inventor. An exhaustive survey of all languages used over the past twenty years in Western Europe and the US would be time‐consuming and of questionable utility; however, it seems safe to suggest that the number is considerably in excess of 1,000. Sammet's latest annual survey lists 132 languages currently in use in the United States, and this can only be a minor fraction of those that have been constructed at one time or another.

The purpose of this paper is twofold: first, to observe an influence of different Composite Fibre-Reinforced Polymer (CFRP) patches, whose application to metals is very easy, in suppling and significantly elongating the service time; and second, the numerical calculation of the reduced stress intensity factor (SIF) range for strengthened cracked steel specimens.

One of the successful strengthening methods is the CFRP patching along the fatigue crack paths. The presented approach has been studied and discussed in this paper on the background of the numerical and experimental data. As it was expected, the proposed strengthening method is efficient and promising in case of the “immediate” repairs of critical members with cracks. The manufacturing process of specimens and test methodology as well as numerical approach to calculate SIFs for various reinforcements of steel specimens are presented. For this purpose, the Extended Finite Element Method was involved and described.

The main mechanism of fatigue crack growth retardation is associated with local ΔK reduction due to CFRP patches; any type of reinforcement results in an increase in a_f and a significant decrease in SIF values. The beach-marking method is described as a good, reliable and comprehensive method to capture the crack propagation in structures consisting of various materials and could be applied successfully for mixed mode testing.

A detailed experimental-numerical approach for fatigue crack growth in long-term operated structures made of steel is presented. The strengthening methodology is presented with consideration of the various CFRP patches configurations.

Avant‐propos sous les auspices de l'Institut international de Coopération intellectuelle, paraissait en 1934 le t. I, consacré à l'Europe, du Guide international des Archives. Le questionnaire envoyé à tous les États européens comportait sous les points 4 et 6 les questions suivantes: ‘Existe‐t‐il un guide général pour les diverses catégories d'Archives ou des guides particuliers pour l'une ou l'autre d'entre elles?’ et ‘Existe‐t‐il des catalogues imprimés, des publications tant officielles que privées, susceptibles de constituer un instrument complet de référence pour tout ou partie importante des fonds d'archives?’ Les réponses des divers pays à ces questions, malgré leur caractère très inégal, ont fait du Guide international un bon instrument d'information générale sur les Archives. Malheureusement les circonstances ont empêché la publication du volume consacré aux États non européens, tandis que le temps qui s'écoulait tendait à rendre périmés les renseignements fournis sur les Archives européennes.

This study aims to explore the conditions of successful implementation of Quality 4.0 in higher education institutions (HEIs) and the key factors affecting it, as well as the role of the Triple Helix collaborative (THC) framework in enhancing the integration of Quality 4.0 principles and Industry 4.0 technologies.

A survey-based strategy was adopted, adopting questionnaires distributed amongst researchers chosen based on their publications related to the aforementioned fields.

The successful integration of disruptive technologies, Quality 4.0 and THC in HEIs heavily relies on educators' continuous learning and professional development. Faculty members must acquire digital skills and competencies to effectively adopt disruptive technologies and implement Quality 4.0 principles in their teaching practices. HEIs should provide opportunities for faculty members to engage in ongoing training programmes, workshops and communities of practice that focus on enhancing their technological proficiencies, pedagogical strategies and collaborative skills.

To the best of the authors' knowledge, this is the first reported study linking the concepts of Quality 4.0 and the Triple Helix of Innovation in HEIs.