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The purpose of this paper is to examine the effect of changing some riveting parameters on the riveting quality of a riveted aircraft structure. In this study, riveting was performed by applying friction under pressure.

During this friction riveting process, a feed of 3 mm/min was applied in the axial direction. Rotation speed values of 2,000, 2,200 and 2,400 rpm were selected. A 3-axis die milling machine was used to achieve the required positioning, pressing force and friction effect. 1.27 mm-thick Al 7075-T6 sheets and 2117-T3 forged rivets were used. The feed rate was applied at 1 mm/min in both tensile shear and cross-tensile tests.

The feasibility of friction riveting in 2117-T3 rivets was examined, it was shown that it could be done, and the most suitable rotation value for this process was determined.

Clamping force is one of the most important parameters for riveting quality. This study will contribute to a better understanding of the friction-forging riveting process along with the effects of riveting parameters. At the same time, it will lead to more research and expand the application of friction forging riveting to more structural connections.

The purpose of this study is to examine the effect of the rivet heads formed on the rivet strength by an experimental study if the bucking bar used in the forged rivet application includes gaps with different angles.

0.81 (0.032”) mm thick 2024 T3 sheets were used for the rivet joints. AD 2117 T4 forged rivets with a diameter of 3.2 mm (0.125″, 1/8″) are used for the joints. The special bucking bars (sidewall intersection angles of flat, 40°, 60° and 80°) were manufactured for the riveting process. To determine the mechanical properties of the prepared samples, cross-tension and tensile-shear tests were performed on a universal tensile testing machine.

As a result of the tensile-shear tests and cross-tensile, use of an 80 degrees bucking bar instead of rivets with a flat bucking bar increases the strength of the joint by approximately 20%. There is no systematic change in elongation. The results of tensile-shear and cross-tensile tests showed that forging rivets by special bucking bars have a significant effect on joint strength.

Increase in strength will require the use of thinner sheet metal and smaller rivets to achieve the same strength. This will reduce the weight of the aircraft. Weight reduction also means less fuel consumption and more economical flight. This increase in strength is a very important scientific achievement.

This paper aims to manage the word gap in information retrieval (IR) especially for long documents belonging to specific domains. In fact, with the continuous growth of text data that modern IR systems have to manage, existing solutions are needed to efficiently find the best set of documents for a given request. The words used to describe a query can differ from those used in related documents. Despite meaning closeness, nonoverlapping words are challenging for IR systems. This word gap becomes significant for long documents from specific domains.

To generate new words for a document, a deep learning (DL) masked language model is used to infer related words. Used DL models are pretrained on massive text data and carry common or specific domain knowledge to propose a better document representation.

The authors evaluate the approach of this study on specific IR domains with long documents to show the genericity of the proposed model and achieve encouraging results.

In this paper, to the best of the authors’ knowledge, an original unsupervised and modular IR system based on recent DL methods is introduced.

This study contributes to the conversation on international career development and its antecedents. Drawing on experiential learning theory and social cognitive theory, the current comparative study investigates the extent to which students' pre-existing international experience (IE) drives their cultural intelligence (CQ) development and influences global career intention for human resource planning purposes.

This study has a comparative nature and adopts quantitative research methodology, which includes survey measures of CQ index, IE and intention to work abroad variables. Quantitative data are collected from a sample of more than 400 business students of leading Australian and Russian universities.

This study showed that IE variables are positively related to the level of CQ facets; the authors showed that Motivational CQ is the strongest predictor for the Intention to work abroad for both countries; the authors proved that students' IE is positively related to an Intention to work abroad for both countries and is partially mediated by CQ for Australia; and study showed that geographical isolation facilitates higher intention to work abroad than political isolation.

Deeper understanding of students' international career intentions and its antecedents will allow practitioners to provide better preparation for local/global careers and will allow students to make more informed and decisions. Companies would benefit from the ability to predict applicants' intention to work abroad. Stronger awareness of own preferences and available trajectories will allow students to select the best fit for them.

This study extends the conversation on international career development and its antecedents in the students' domain by strengthening measurements of IE and advancing the understanding of relationship between previous IE and individual facets of CQ. An empirical data from isolated locations – Russia (politically) and Australia (geographically) – bring a new timely contribution about a role of the isolation in shaping international career intentions.

This research aims to examine some nudges for creating psychological ownership in order to reduce misbehaviors, consequently encouraging subsequent users to demonstrate stewardship behaviors.

This research examined the sentiment of tweets (Study 1) to explore user experience and conducted two experiments (Studies 2 and 3) to test the hypotheses.

The misbehavior of the previous user in relation to the subsequent user's stewardship behavior was moderated by nudges based on self-investment and local identity. Perceived responsibility mediated the relationship between misbehavior and stewardship behavior as a result of nudges.

The findings of this study provide a framework for the transition from misbehavior to stewardship behavior in PMVs.

The purpose of this paper is to examine the involvement of the concept of city identity in the design process of urban densification and outline how can today's urban projects be able to reinforce the delicate balance between conservation, development management and sustainability objectives.

Based on case study approach, this paper focus on “Park Mall and Four Point Hotel” project, located in the historic city centre of Setif (Algeria) and takes the procedure of designing as its conceptual framework. Following this, it explores genesis document of the project and assesses architect's choices attributed to six elements of architectural language. These elements are apprehended regarding their relevance, which depends on whether the new building is or not compatible/integrated with the existing environment, and how far does it reinvent the modern vision.

The paper provides empirical insight about how the concept of identity is used during the design process of densification project. It argues that this latter consists on a dynamic process shaped by cultural, socioeconomic and institutional specificities applying local/global design precedents, multifunctionality concept and novel features in a tourism-oriented mindset and to still maintain and improve the specific identity of the city centre, thus becoming an active way to reconcile conservation, sustainability and development management objectives.

This paper raises discussion on how the concept of city identity could renew the field of heritage conservation and development management. Therefore, it fulfils an identified need to study how can urban projects reconcile conservation, development management and sustainability objectives.

This paper's purpose is to explore the current interest and knowledge that UK consumers hold around agroforestry. Despite the many reported benefits of agroforestry systems, uptake in the UK, as well as other temperate nations, has been low. As the consumer has a role to play in the transition of agriculture to methods that are more environmentally friendly it is vital to have an understanding of their perceptions. Yet to date no work has looked at agroforestry from the perspective of the UK consumer.

An online survey was conducted using a convenience sample accessed by floating a link through social media and messaging apps. The survey was also shared to the members of a private Facebook group associated with an organic vegetable box service. A mix of multiple choice and open text boxes were used. The survey received 139 responses.

Non-parametric tests indicate that this sample of UK consumers would be mostly likely to buy, and willing to pay more for, agroforestry produce; and the sample showed a split group regarding familiarity. Inductive thematic analysis of the qualitative data highlighted some important barriers to the purchase as well as capturing a snapshot of this sample's perceptions.

This paper presents, to the authors knowledge, the first set of data regarding a sample of UK consumers' perspective of agroforestry produce. The findings could bolster producers' confidence in adopting agroforestry practices, but also highlight the need for policymakers to bolster consumer support through parallel means.

This study aims to analyse the components of sustainable business models (SBMs) in the dairy industry, in relation to firm-relevant organisational features (size, ownership structure and production process) and through the lenses of the business model framework and the sustainable value exchange matrix (SVEM). This contribution proposes a taxonomy of emerging SBMs and sustainable value creation in the dairy industry.

This research makes use of a multiple case study approach, with cases selected in collaboration with industry experts. The selected firms are highly committed to sustainability transition. Results are drawn from qualitative data obtained from in-depth interviews and secondary sources. The interpretation phases, initially based on open coding, have been enriched by applying the components of business models (BMs) frameworks and the SVEM, and the analyses have been enhanced through an additional interpretative workshop with experts.

The authors related the BMs characteristics of some typical dairy firms transitioning to sustainability, using SBM components and taxonomies emerging in the literature, based on the formalisation of sustainability practices, the scope of operations, and the degree of integration of the three dimensions of sustainable value. These findings led to the discovery of three types of SBM in this dairy industry, referred to as “Milky Ways”.

This paper contributes to the scant literature on sustainability in dairy firms, highlighting the different paths followed by small and medium-sized enterprises (SMEs), cooperatives and large companies in remoulding their business models towards sustainability and thus achieving sustainable value creation.

Halal food (HF) has received significant attention from scholars and practitioners. However, no studies have explored the distinct role played by HF literature as part of knowledge diffusion. Given the increasing number of scholarly outputs, this study aims to examine the HF development over the past decades comprehensively, including emerging topics and knowledge transmission paths and structure.

This study conducted a keyword co-occurrence network analysis and main path analysis (MPA). The MPA included four types of main paths to trace the historical formation of HF based on 253 articles extracted from the Web of Science database.

The findings show that: HF research revolves around several dimensions, including HF safety and trust, halal certification, HF supply chain management and attitudes towards HF purchasing, and the focus of HF research has shifted from the business perspective to the consumer perspective. In recent years, there has been a trend to explore how blockchains can benefit HF supply chains by improving traceability, transparency and consumer trust in HF.

This study addresses the need to examine the knowledge diffusion paths in the HF domain. This study offers a framework to investigate the knowledge dissemination and structure, helping researchers deal with hundreds of articles effectively and increasing their understanding of the past, present and future research trends in the HF domain.

This study aims to use computational fluid dynamics (CFD) to understand and quantify the overall blockage within a transonic axial flow compressor (AFC), and to develop an efficient collaborative design optimization method for compressor aerodynamic performance and stability in conjunction with a surrogate-assisted optimization technique.

A quantification method for the overall blockage is developed to integrate the effect of regional blockages on compressor aerodynamic stability and performance. A well-defined overall blockage factor combined with efficiency drives the optimizer to seek the optimum blade designs with both high efficiency and wide-range stability. An adaptive Kriging-based optimization technique is adopted to efficiently search for Pareto front solutions. Steady and unsteady numerical simulations are used for the performance and flow field analysis of the datum and optimum designs.

The proposed method not only remarkably improves the compressor efficiency but also significantly enhances the compressor operating stability with fewer CFD calls. These achievements are mainly attributed to the improvement of specific flow behaviors oriented by the objectives, including the attenuation of the shock and weakening of the tip leakage flow/shock interaction intensity.

CFD-based design optimization of AFC is inherently time-consuming, which becomes even trickier when optimizing aerodynamic stability since the stall margin relies on a complete simulation of the performance curve. The proposed method could be a good solution to the collaborative design optimization of aerodynamic performance and stability for transonic AFC.