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Friction stir welding (FSW), a process that involves joining of metals without fusion of filler materials. It is used already in routine, as well as critical application for the joining of structural components made of Aluminum and its alloys. Indeed it has been convincingly demonstrated that the process results in strong and ductile joints, some times in systems, which have proved difficult using conventional welding techniques. The process is most suitable for components that are flat & long (plates & sheets) but it can be adapted for pipes, hollow sections and positional welding. The welds are created by the combined action of frictional heating and mechanical deformation, due to a rotating tool. Recently, a new technology called friction stir spot welding (FSSW) has been developed that has a several advantages over the electric resistance welding process widely used in automotive industry in terms of weld quality and process efficiency. This welding technology involves a process similar to FSW, except that, instead of moving the tool along the weld seam, the tool only indents the parts, which are placed on top of each other. The conditions under which the deposition process in FSSW is successful are not fully understood. However, it is known that only under specific thermo‐mechanical conditions does a weld formation occur. The objective of the present work is to analyze the primary conditions under which the cavity behind the tool is filled. For this, a fully coupled thermo‐mechanical three‐dimensional FE model has been developed in ABAQUS/Explicit using the adaptive meshing scheme and the Johnson‐Cook material law. The contact forces are modeled by Coulomb’s law of friction, making the contact condition highly solution dependent. Temperature graph in the radial direction as well as stress, strain plots are presented.

Pressure vessel is a closed cylindrical vessel for storing gaseous, liquids or solid products. The stored medium is at a particular pressure and temperature. The cylindrical vessel is closed at both ends by means of dished head, which may be hemispherical, ellipsoidal. The pressure vessels may be horizontal or vertical. The supporting system of this vertical vessel plays an important role in the performance of the equipment. Proper supporting system gives better efficiency. The bottom supports are critical components since they are to be designed with much care to avoid failure due to internal pressure with temperature. In this analysis, skirt support for vertical vessel was analyzed as per the guidelines given in the ASME (American Society of Mechanical Engineering) section VIII division 2 and IBR (Indian Boiler Regulations) standards. The stress analysis was carried out for this support using a general purpose FEM code, ANSYS macros. The coupled field (Structural and Thermal) Analysis was carried out for skirt support to find out the stresses in the support. The analysis’s results were compared with ASME code allowable stress values.

Meetings can serve the important role of facilitating communication and coordination for systems of teams known as “multiteam systems” (MTSs) that work interdependently to achieve grand societal challenges. Given that MTSs often appear in complex, ambiguous, urgent, and multifaceted task contexts, the MTSs require effective, and efficient but thorough, communication within and between teams in order to achieve shared goals. However, the extant literature regarding the science of meetings has left much to be explored in regard to the inter- and intrateam influences and impacts. This chapter considers the significance of meetings and their practical value in facilitating MTS processes and performance by leveraging what is known thus far regarding MTS structural attributes, their value, their challenges, and opportunities, integrating this foundation with the broader science of meetings. Building on this rationale, the authors move toward empirically and theoretically derived considerations for how meetings may best be designed, facilitated and utilized for MTS effectiveness, as guided by our current understanding of critical MTS attributes.

The study aims to advance understanding of the intention of Augmented Reality (AR) technology adoption by conducting a systematic review of relevant literature articles in the hospitality sector where 93 articles were chosen and synthesized by generating a theme and proposing a conceptual framework with their research proposals.

A systematic literature review (SLR) has been conducted incorporating thematic analysis to investigate various determinants from selected articles and to identify the key themes in order to propose a conceptual framework and research proposal.

The findings reveal seven major themes in its research proposal for future research directions. This includes “Technology Engagement”, “Resilience”, “Knowledge is key”, “Readiness for changes”, “Uncertainty management”, “Environmental conditions” and “Business performance”.

The novel contribution of this study is that it focuses on both theoretical and practical knowledge. On the theoretical level, this study comprises factors that apply relevant theory in the areas of information technology and business management, whose integrative theoretical orientation provided insight into the AR adoption initiatives and to further examine the relationship between its proposed factors. On the practical level, it provides insights and information with a new body of knowledge that business owner–managers, policymakers and practitioners should consider in order to craft a strategic adoption of AR technology.

The purpose of this paper is to join a sheet of the AA7075 with the high-density polyethylene (HDPE) by a lap joint using friction spot processing and investigate the temperature distribution of joint during this process using the finite element method (FEM).

A semi-conical hole was manufactured in the AA7075 specimen and a lap joint configuration was prepared with the HDPE specimen. A rotating tool was used to generate the required heat to melt the polymer by the friction with the AA7075 specimen. The applied tool force moved the molten polymer through the hole. Four parameters were used: lower diameter of hole, rotating speed, plunging depth and time. The results of shear test were analyzed using the Taguchi method. A FEM was presented to estimate the temperature distribution of joint during the process.

All specimens failed by shearing the polymer at the lap joint region without dislocation. The specimens of the smallest diameter exhibited the highest shear strength at the lap joint. The maximum ranges of temperature were recorded at the contact region between the rotating tool and the AA7075 specimen. The tool plunging depth recorded the highest effect on the generated heat compared with the rotating speed and plunging time.

For the first time, the AA7075 sheet was joined with the HDPE sheet by friction spot processing. The temperature distribution of this joint was simulated using the FEM.

The purpose of this paper is to understand the effect of basin water depth towards the cumulative distillate yield of the traditional and developed single basin double slope solar still (DSSS).

Modified single basin DSSS integrated with solar operated vacuum fan and external water cooled condenser was fabricated using aluminium material. During sunny season, experimental investigations have been performed in both conventional and modified DSSS at a basin water depth of 3, 6, 9 and 12 cm. Production rate and cumulative distillate yield obtained in traditional and developed DSSS at different water depths were compared and best water depth to attain the maximum productivity and cumulative distillate yield was found out.

Results indicated that both traditional and modified double SS produced maximum yield at the minimum water depth of 3 cm. Cumulative distillate yield of the developed SS was 16.39%, 18.86%, 15.22% and 17.07% higher than traditional at water depths of 3, 6, 9 and 12 cm, respectively. Cumulative distillate yield of the developed SS at 3 cm water depth was 73.17% higher than that of the traditional SS at 12 cm depth.

Performance evaluation of DSSS at various water depths by integrating the combined solar operated Vacuum fan and external Condenser.

The debriefing is a procedure based on intra-team feedback, which has frequently been applied in university formation in health but has been less used in business. The aim of this research is to analyse best practices in the actual implementation of debriefing in organisations, based on criteria the guidelines for carrying out each stage established in the procedure.

To achieve these goals, working teams from different organisations carried out 19 group-debriefing sessions on an authentic work problem. These sessions were observed and analysed following a qualitative approach.

After observing a debriefing session in 19 organisations, four categories related to its implementation have been identified: Self-analysis, information, planning and orientation of the development of the team.

It is important to mention some limitations to this work. The major limitation was the lack of published literature related to the debriefing in the area of organisational management. The qualitative and exploratory nature of the study limits the generalisation of the results.

The research has practical implications as the characterisation and description of each phase favours the transfer to implement the debriefing technique adequately in different types of organisations.

It has been observed that all forms of debriefing have a common purpose in learning and, team and employee development, due to the powerful transferability and usefulness of debriefing in different contexts. Therefore, knowing the correct use of debriefing is a breakthrough in this area. In addition, including this type of practice will not just facilitate a better performance, it will also help teams to learn to work in a team from their own experiences.

It has been characterised by the process of debriefing from the correct implementation of each phase through the analysis of the narratives that arise in the debriefing sessions carried out.

匯報是一個基於團隊內部回饋的程序, 它常見於大學組建的醫療衛生方面, 在商業上則較少使用。本研究擬基於匯報程序中所建立的每個階段, 來分析在組織內實際進行匯報的典範實務。

為達至研究目標, 來自不同組織的工作團隊, 就一個真實的工作問題進行了19個匯報會議。研究人員觀察這些會議, 並以定性研究法進行探討和分析。

研究人員觀察於19個組織進行的匯報會議後, 找出了四個進行匯報會議的範疇, 自我分析、資料、計劃和團隊發展的取向。

本研究提供了實務方面的啟示, 因研究結果確認了匯報每個階段的特徵的描述, 以及每個階段的描述, 這會幫助在不同種類的組織內進行匯報會議時, 舉行匯報使用之技巧得以靈活調動, 以發揮各技巧的最佳效果。

研究人員分析有關的匯報會議內的敘述, 並從會議每個階段的正確執行, 找出了匯報程序的各個特徵。

In an ever-interconnected world dominated by discourses on the internationalization and marketization of higher education, concerns related to language and employability have been the focus of recent debates. There is, however, a dearth of research investigating how these dimensions relate to one another in recent comparative and international higher education research. By focusing on how issues related to language and employability have been presented in recent higher education research worldwide, this chapter aims to contribute to our understanding of this concern. To achieve this goal, we conducted a scoping literature review using the Web of Science, Scopus, and the Education Resources Information Center (ERIC) databases, considering the years 2011–2020. The findings, perhaps not surprisingly, suggested that language skills are perceived to be valued by both graduates and employers though the discussions predominantly focused on one language, English. The research focus on English for employability in Anglophone contexts is understandable. However, the fact that the trend is observed in contexts where the language is not the primary or official language seems to indicate the influence of internationalization of higher education and global labor markets primarily dominated by English. The literature also suggested that (English) language training in higher education programs needs to move from solely linguistic and qualification-related content areas to a broader sphere of English for communication purposes that cover both specialized disciplinary content and broader generic employability skills. Considering this finding, we suggest that higher education systems and institutions incorporate recent developments in English for occupational purposes in their curriculum. We also recommend that there needs to be a shift from the overwhelmingly English language-dominated discussions to more inclusive research that assesses the impact of other dominant languages on employability-related concerns.

Solar-driven water desalination technologies are rapidly developing with various links to other renewable sources. However, the efficiency of such systems severely depends on the design parameters. This paper presents results from an investigation on the effect of the glass cover inclination angle on the performance of two stepped solar still geometries (flat and convex) and the amount of produced distilled water.

Studied inclination angles of 25°, 27.5°, 30°, 32.5° and 35° were chosen, while other design parameters were fixed.

The investigation showed that the unit with the convex absorber plate had higher average water daily production rate, compared to the output of the flat absorber plate unit. The results also depicted that the inclination angle of the still has a noticeable effect on the performance of solar stills. The value of the critical angle is 32.5°, and the higher inclination angle results in less heat transfer coefficient. This value can be used for design purposes and erases the typical assumption to use lower angles to optimize the productivity of the still.

Finally, obtained data were used to correlate the Nusselt number for the flat and convex surfaces with different inclination angles of the glass cover.

The outcome of this investigation may find applications to develop highly efficient solar stills to secure more drinkable water in warm, dry lands.

The main purpose of this paper is to estimate the resistance and inductor in the RL electrical circuit when these are unavailable or missing data that it is a concern in electrical engineering. The input voltage is assumed to be corrupted by the noise and the current is observed at discrete time points.

The authors propose a computationally efficient framework for parameters estimation using least square estimator and Bayesian Monte Carlo scheme.

The explicit formulas for least square estimator are derived and the strong consistency of resistance estimator is verified when inductor is a known parameter, then Bayesian estimation of parameters governed by using Markov chain Monte Carlo methods. The applicability of the results is demonstrated by using numerical examples. Several numerical results and figures are presented via Matlab and R programming to illustrate the performance of the estimators.

The paper can be used in various types of electrical engineering real time projects. The projects include electrical circuits, electrical machines theory and drives, especially when the parameters are uncertain that it is a worry in electrical engineering.

To the author's best knowledge, least square and Bayesian estimation of resistance and inductor have not been studied before. The proposed model is nonlinear with respect to inductor (L); therefore the present work has fundamental difference in comparison with the similar models.