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This study aims to investigate the influences of polyester fabric layers on the mechanical properties of SBR and devulcanized waste rubber composite materials, as well as the effect of gamma irradiation dose.

The devulcanized waste rubbers (DWR) were carried out by different methods. First, chemically, by two different reclaiming agents such as tetramethylthiuram disulfide (TMTD) and 2-mercapto benzothiazole disulfide (MBTS). Secondary by a physical method like microwave (MW). The devulcanized rubbers were mixed with virgin styrene butadiene rubber (SBR) in different ratios, as follows: SBR-DWR (TMTD) 50 / 50, SBR-DWR (MBTS) 80 / 20 and SBR-DWR (MW) 80 / 20. A series of sandwich polyester tire cord fabrics were used as reinforcement for making SBR and devulcanized waste rubber composite materials and molded on a hot press into rubber sheet films, then subjected to gamma radiation at different doses ranging from 100 up to 200 kGy.

The experimental results indicate that increasing the layer number improves the mechanical properties of composites. The tensile strength, tearing, hardness and elastic modulus of the rubber composites increased with the rise of the fiber layers and by increasing the irradiation dose up to 200 kGy. The reclaiming agent TMTD gave the best results for mechanical properties, followed by MW and then MBTS.

This phenomenon can be detailed based on the fact that when the fiber-reinforced composites are subjected to loading, the fibers act as load carriers, depending on the population and orientation of the fibers. Also, scanning electron microscopy (SEM) reveals that adhesion was caused by tire cord fabrics and rubber blend matrix.

This essay reflects on over two decades of developing global leaders while simultaneously studying global leadership phenomena. Global leadership is leading across contexts. Because the contexts of global business continuously evolve, so too must our understanding of global leadership and our research about it. When research and practice inform each other in constant iteration, we can develop knowledge that is robust and relevant, and identify emerging ideas that shape future knowledge and practice. The essay suggests that exceptional, high-impact global leaders demonstrate two characteristics in addition to the competences and qualities identified in most research. Self-acceptance is an internal orientation, an acknowledgement of one’s own strengths, weaknesses, and reasons for leading. It underlies the ability to manage the impact of one’s self on others, and creates a leadership space for empowerment of others. Community transcendence is an external orientation, an acknowledgement of the primacy of local for creating meaning in business and work. It enables a leader to take on a local identity and create a leadership space for the community to succeed through the global organization. The essay concludes with speculation on the future importance of these two qualities.

This paper aims to provide insights into the complicated relationship between earnings management (EM) and corporate social responsibility (CSR) during the financial downturn caused by the COVID-19 pandemic.

Parametric t-tests and non-parametric Wilcoxon rank-sum tests accompanied by ordinary least squares regression analysis, augmented with Newey–West procedure approaches, are used for a sample that consists of 1,984 firms from 47 countries for the period of 2014–2020. EM was proxied once with discretionary accruals using the modified Jones model (1995) and once with real earnings management (REM) using the Roychowdhury model (2006). This study uses environmental, social, and governance scores from the Thomson Reuters database as a proxy for CSR.

The results reveal that firms tend to engage more in EM practices during the pandemic and that more socially responsible firms tend to be honest and transparent during the financial reporting process. Interestingly, it was found that more socially responsible firms engaged less in REM practices during the pandemic.

The findings of this research help lenders, investors, policymakers and managers gain a better understanding of EM practices during a negative shock and shed light on the importance of CSR in being ethical.

The findings extend both the literature on the role of CSR in promoting financial reporting quality and the literature on the impact of COVID-19 on accrual and REM practices.

This paper is based on a study which examined the current training evaluation activity and challenges that face Kuwaiti organisations. The study sample was five UK organisations (recognised as best practice organisations in their T&D activities) and 77 Kuwaiti organisations (40 government and 37 private). Interviews and questionnaires were used. The study reveals that the majority of respondents, both in government and in private sectors, only evaluate their training programme occasionally. The most popular evaluation tools and technique used by government and private sectors were questionnaires. The most common model used by Kuwaiti organisations is the Kirkpatrick model, while the most common level of evaluation for both government and private sector is reaction type.

Heritage buildings are a witness to previous civilizations and constitute important elements in transmitting cultural identity through generations. In 1938, Alexandria University was established; it was called the University of Farouk at the time. In 1952, the university was named “Alexandria University,” and since then, it has witnessed growth and expansion in several fields. The research aims to preserve the heritage of this academic institution. It seeks to document this wealth of buildings that tell the story of the second-earliest university in Egypt.

A mixed-method approach was employed. A descriptive method was used to narrate the history of the university and the importance of its buildings. Within the quantitative approach, a questionnaire was chosen as the survey instrument for collecting the data within the research case study. The aim was to determine the awareness of students, staff and employees of the heritage importance of their faculty. Within the qualitative approach, several interviews were conducted with employees in the engineering departments of the university administrative building at Chatby and some of the selected faculties. The aim was to determine the methods used for the conservation of these buildings.

Alexandria University has a heritage value not only in its great history but also through its heritage buildings. Raising the awarness of the university's affiliates of this heritage will lead to enhance the feelings of loyalty and belongings to the university. Therefore, preserving this heritage and properly managing it is crucial.

Universities have to recognize that their built heritage constitutes a unique expression that can create a distinctive sense of place. University heritage is crucial in defining and interpreting the university cultural identity. The institution must identify resources that will help build a new public image and contribute to develop a successful brand. Campus appearance is an important factor that has a significant impact on student feelings of loyalty and belonging.

Given the increased importance of food in tourists’ travel experience, the purpose of this paper is to explore the current and future potential of local food and foodways in marketing Egyptian destinations online.

The content of 20 Egyptian destination marketing organization (DMO) websites was subject to a content analysis. A checklist was developed based on literature analysis. The frequencies of information related to food culture and cuisine marketing were tallied, followed by a qualitative assessment of contents from the various websites. The results were further discussed with DMO representatives to provide contextualized insights as to the future potential of utilizing local food and food tourism initiatives as a component of DMOs website marketing in Egypt.

The study noted some initial efforts for Egyptian DMO websites to market food culture and gastronomic practices; however, the results suggest that the usage of food culture on Egyptian DMOs websites is still in its infancy. The study also highlights the challenges that need to be tackled as well as the resources required for food tourism development.

This study illustrates the need and potential capacity of Egyptian DMO websites to market food culture and local cuisines (including traditional foods and table manners). These results are expected to help Egyptian DMOs to strategically embrace local cuisine and food culture as a vehicle for destination marketing.

This case study provides insights for African and other developing economies in their destination marketing. The proposed framework and guidelines are intended to potentially serve as a framework for destination marketers and entrepreneurs to optimize the tourism potential of food culture.

The aim of this research is to examine the relationship between green supply chain management and sustainability performance in a manufacturing context.

A survey approach was adopted to collect data from 163 manufacturing organizations to test the research hypotheses. A structural equation modeling (SEM) using the technique of path analysis with bootstrapping is used to test the hypothesized relationships.

The research findings provide supporting evidence for the importance of implementing green supply chain management (GSCM) as a holistic system that includes internal and external green practices. Besides, the findings highlight the direct effect of GSCM on environmental, social and operational performance. Finally, the findings provide supporting evidence that GSCM could only be translated into better economic returns through the improvement of environmental and operational performance.

The nature of the surveyed sample and the use of a single informant might limit the ability to generalize the research findings outside the research context.

The research findings help managers understand that GSCM must be implemented as a holistic system and that the real benefits of its implementation extend beyond the mere environmental benefits to include operational, social as well as economic benefits.

The paper’s contribution to knowledge is twofold. First, the study identifies how GSCM is conceptualized and how its effect is translated into improved economic performance. Second, the research explains the contradicting findings in previous studies regarding the relationship between GSCM and economic performance.

The study proposed a human–robot interaction (HRI) framework to enable operators to communicate remotely with robots in a simple and intuitive way. The study focused on the situation when operators with no programming skills have to accomplish teleoperated tasks dealing with randomly localized different-sized objects in an unstructured environment. The purpose of this study is to reduce stress on operators, increase accuracy and reduce the time of task accomplishment. The special application of the proposed system is in the radioactive isotope production factories. The following approach combined the reactivity of the operator’s direct control with the powerful tools of vision-based object classification and localization.

Perceptive real-time gesture control predicated on a Kinect sensor is formulated by information fusion between human intuitiveness and an augmented reality-based vision algorithm. Objects are localized using a developed feature-based vision algorithm, where the homography is estimated and Perspective-n-Point problem is solved. The 3D object position and orientation are stored in the robot end-effector memory for the last mission adjusting and waiting for a gesture control signal to autonomously pick/place an object. Object classification process is done using a one-shot Siamese neural network (NN) to train a proposed deep NN; other well-known models are also used in a comparison. The system was contextualized in one of the nuclear industry applications: radioactive isotope production and its validation were performed through a user study where 10 participants of different backgrounds are involved.

The system was contextualized in one of the nuclear industry applications: radioactive isotope production and its validation were performed through a user study where 10 participants of different backgrounds are involved. The results revealed the effectiveness of the proposed teleoperation system and demonstrate its potential for use by robotics non-experienced users to effectively accomplish remote robot tasks.

The proposed system reduces risk and increases level of safety when applied in hazardous environment such as the nuclear one.

The contribution and uniqueness of the presented study are represented in the development of a well-integrated HRI system that can tackle the four aforementioned circumstances in an effective and user-friendly way. High operator–robot reactivity is kept by using the direct control method, while a lot of cognitive stress is removed using elective/flapped autonomous mode to manipulate randomly localized different configuration objects. This necessitates building an effective deep learning algorithm (in comparison to well-known methods) to recognize objects in different conditions: illumination levels, shadows and different postures.

In the present paper, the new concept of “memory dependent derivative” in the Pennes’ bioheat transfer and heat-induced mechanical response in human living tissue with variable thermal conductivity and rheological properties of the volume is considered.

A problem of cancerous layered with arbitrary thickness is considered and solved analytically by Kirchhoff and Laplace transformation. The analytical expressions for temperature, displacement and stress are obtained in the Laplace transform domain. The inversion technique for Laplace transforms is carried out using a numerical technique based on Fourier series expansions.

Comparisons are made with the results anticipated through the coupled and generalized theories. The influence of variable thermal, volume materials properties and time-delay parameters for all the regarded fields for different forms of kernel functions is examined.

The results indicate that the thermal conductivity and volume relaxation parameters and MDD parameter play a major role in all considered distributions. This dissertation is an attempt to provide a theoretical thermo-viscoelastic structure to help researchers understand the complex thermo-mechanical processes present in thermal therapies.

This study aims to develop a film dosimeter composed of 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MMT) dye and polyvinyl butyral (PVB) binder to reduce the effect if relative humidity effect during irradiation.

The films were exposed to gamma ray radiation from a ⁶⁰Co gamma ray source with 8.6 kGy/h dose-rate and 1.25 MeV beam energy to various doses ranging from 2.5 to 100 kGy. UV-VIS spectrophotometer was used to measure the changes in optical properties of irradiated films by means of the changes in the absorbance values at wavelength of 560 nm.

The effect of irradiation temperature, relative humidity, fluorescent light and postirradiation stability on the performance of developed film dosimeter were investigated.

Previous MMT dye with PVA binder was significant effect of the relative humidity on the dose response of MMT-PVA films which decrease the practical feasibility of using these films in routine high-dose measurements. Therefore, the purpose of this study is to reduce the relative humidity effect on the dose response by proposing a formula for film dosimeters that combines MMT dye with the polyvinyl butyral (PVB) binder.

The irradiation of MMT-PVB films leads to a change in color from yellow to brown, which could be evaluated by the absorbance intensity.