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This paper aims to investigate the friction noise properties of M50 matrix curved microporous channel composites filled with solid lubricant Sn-Ag-Cu (MS).

Pure M50 (MA) and MS are prepared by selective laser melting and vacuum-pressure infiltration technology. The tribological and friction noise properties of MA and MS are tested through dry sliding friction and then the influential mechanism of surface wear sate on friction noise is investigated by analyzing the variation law of noise signals and the worn surface characteristics of MS.

Experimental results show that the friction noise sound pressure level of MS is only 75.6 dB, and it mainly consists of low-frequency noise. The Sn-Ag-Cu improves the surface wear state, which reduces self-excited vibration of the interface caused by fluctuation of friction force, leading to the decrease of friction noise.

This investigation is meaningful to improve the tribological property and suppress the friction noise of M50 bearing steel.

This paper aims to investigate the effects of intrinsic and extrinsic motivations represented in religious motivation and customer equity (CE) drivers, respectively, and switching costs (SCs), on customer’s retention to conventional banks and their switching intention (SI) to Islamic ones in the context of the Egyptian banking sector.

Based on the literature, a theoretical model is proposed and examined using structural equation modeling (AMOS) 24. Data were obtained using an intercept sample of 273 conventional bank customers in two major cities in Egypt, namely, Cairo and Giza.

The results supported the positive effect of CE and SCs on customer retention (CR) to conventional banks. Value equity has direct positive effect on CR. In addition, SC significantly mediated the relationship between relationship equity (RE) and service encounter employee’s equity (SEEE) and CR. Finally, religious motivations positively and significantly influence customers SI to Islamic banks.

CE, including all its drivers, namely, value, brand, relationship and SEEE, are the best force of CR in the Egyptian banking sector. The mediating role of SC in the relation between RE and SEEE and CR is perceived as a barrier to switch, instead of reflecting real desire from customers to stay tuned to their conventional banks. In addition, religious motivation should be considered while planning banking services because of its significant direct effect on customers SI from conventional banks to Islamic ones. Finally, both utilitarian extrinsic motivation and hedonic intrinsic ones are influencing customer’s retention and SI, respectively.

This paper develops and adds a fourth driver to previously examined and validated CE drivers, namely, SEEE. Further, it provides empirical analysis to the effect of religious motivation and CE drivers on SCs, CR and SI in a developing and Islamic dominating context, namely, Egypt. Moreover, it introduces a framework that could be examined and validated in other Islamic contexts to further comprehend bank customers' switching behavior. Yet, the current research focused on the Egyptian banking sector only, where the individual customers represent the sampling unit.

The purpose of the paper is to showcase the significant achievements of Egypt's scientists in the 20th century across various fields of study such as medicine, physics, chemistry, biology, math, geology, astronomy and engineering. The paper highlights the struggles and successes of these scientists, as well as the cultural, social and political factors that influenced their lives and work. The aim is to inspire young people to pursue careers in science and make their own contributions to society by presenting these scientists as role models for hard work and dedication. Ultimately, the paper seeks to promote the importance of science and its impact on society.

The purpose of this review is to present the scientific biographies of Egypt's most distinguished scientists, primarily in the field of Natural Sciences, in a balanced and comprehensive manner. The work is objective, honest and abstract, avoiding any bias or exaggeration. The author provides a clear and concise methodology, including a brief introduction to the scientist and their field of study, an explanation of their major contributions, the impact of their work on society, any challenges or obstacles faced during their career and their lasting legacy. The aim is to showcase the important achievements of these scientists, their impact on their respective fields and to inspire future generations to pursue scientific careers.

The group of outstanding scientists in 20th century Egypt were shaped by various factors, including familial upbringing, education, society, political and cultural atmosphere and state support for scientific research. These scientists made significant contributions to various academic disciplines, including medicine, physics, chemistry, biology, mathematics and engineering. Their impact on their communities and cultures has received international acclaim, making them role models for future generations of scientists and researchers. The history of these scientists highlights the importance of educational investments and supporting scientific research to foster innovation and social progress. The encyclopedia serves as a useful tool for students, instructors and education professionals, preserving Egypt's scientific heritage and honouring the scientists' outstanding accomplishments.

The encyclopedia preserves Egypt's scientific heritage, which has been overlooked for political or other reasons. It is a useful tool for a variety of readers, including students, instructors and education professionals, and it offers insights into universally relevant scientific success factors as well as scientific research methodologies. The encyclopedia honours the outstanding scientific accomplishments of Egyptian researchers and their contributions to the world's scientific community.

The practical implications of this paper are several. First, it highlights the importance of education, family upbringing and societal support for scientific research in fostering innovation and social progress. Second, it underscores the need for continued funding and support for scientific research to maintain and build upon the accomplishments of past generations of scientists. Third, it encourages young people to pursue scientific careers and make their own contributions to society. Fourth, it preserves the scientific heritage of Egypt and honors the contributions of its outstanding scientists. Finally, it serves as a useful tool for students, instructors and education professionals seeking to understand the factors underlying scientific success and research methodologies.

The social implications of the paper include promoting national pride and cultural identity, raising awareness of the importance of education and scientific research in driving social progress, inspiring future generations of scientists and researchers, reducing socioeconomic disparities and emphasizing the role of society, politics and culture in shaping scientific researchers' personalities and interests.

The paper's originality/value lies in its comprehensive documentation of the scientific biographies of Egypt's most prominent scientists in the 20th century, providing unique insights into the factors that contributed to their development and their impact across various academic disciplines. It preserves Egypt's scientific heritage and inspires future generations of scientists and researchers through the promotion of educational investments and scientific research. The encyclopedia serves as a useful tool for education professionals seeking to understand scientific success factors and research methodologies, emphasizing the importance of supportive and inclusive environments for scientific development.

This paper aims to examine the extent to which these reforms address the limitations of Saudi Arabia’s previous investment framework. Long viewed as a hostile environment in which to do business, the Saudi Government has enacted a broad sweep of measures aimed at restoring investor confidence in central aspects of the country’s evolving private law framework.

This paper offers a timely assessment of the raft of foreign investment reforms, both legislative and regulatory, that have been introduced in Saudi Arabia over the last decade.

The paper will proceed by outlining the perceived failings of the old investment regime before going on to reforms.

It will consider the remaining obstacles to the flow of foreign investment in Saudi Arabia in the context of the dual forces that have historically defined the Kingdom’s ambivalent investment law regime.

The current challenge for forecasting smart meters electricity consumption lies in the uncertainty and volatility of load profiles. Moreover, forecasting the electricity consumption for all the meters requires an enormous amount of time. Most papers tend to avoid such complexity by forecasting the electricity consumption at an aggregated level. This paper aims to forecast the electricity consumption for all smart meters at an individual level. This paper, for the first time, takes into account the computational time for training and forecasting the electricity consumption of all the meters.

A novel hybrid autoregressive-statistical equations idea model with the help of clustering and whale optimization algorithm (ARSEI-WOA) is proposed in this paper to forecast the electricity consumption of all the meters with best performance in terms of computational time and prediction accuracy.

The proposed model was tested using realistic Irish smart meters energy data and its performance was compared with nine regression methods including: autoregressive integrated moving average, partial least squares regression, conditional inference tree, M5 rule-based model, k-nearest neighbor, multilayer perceptron, RandomForest, RPART and support vector regression. Results have proved that ARSEI-WOA is an efficient model that is able to achieve an accurate prediction with low computational time.

This paper presents a new hybrid ARSEI model to perform smart meters load forecasting at an individual level instead of an aggregated one. With the help of clustering technique, similar meters are grouped into a few clusters from which reduce the computational time of the training and forecasting process. In addition, WOA improves the prediction accuracy of each meter by finding an optimal factor between the average electricity consumption values of each cluster and the electricity consumption values for each one of its meters.

This study focused on exploring the performance factors (PFs) that impact Infrastructure Sanitation Projects (ISSPs) in the construction sector. The aim was twofold: firstly, to identify these crucial PFs and secondly, to develop a robust performance model capable of effectively measuring and assessing the intricate interdependencies and correlations within ISSPs. By achieving these objectives, the study aimed to provide valuable insights into and tools for enhancing the efficiency and effectiveness of sanitation projects in the construction industry.

To achieve the study's aim, the methodology for identifying the PFs for ISSPs involved several steps: extensive literature review, interviews with Egyptian industry experts, a questionnaire survey targeting industry practitioners and an analysis using the Relative Importance Index (RII), Pareto principle and analytic network process (ANP). The RII ranked factor importance,  and Pareto identified the top 20% for ANP, which determined connections and interdependencies among these factors.

The literature review identified 36 PFs, and an additional 13 were uncovered during interviews. The highest-ranked PF is PF5, while PF19 is the lowest-ranked. Pareto principle selected 11 PFs, representing the top 20% of factors. The ANP model produced an application for measuring ISSP effectiveness, validated through two case studies. Application results were 92.25% and 91.48%, compared to actual results of 95.77% and 97.37%, indicating its effectiveness and accuracy, respectively.

This study addresses a significant knowledge gap by identifying the critical PFs that influence ISSPs within the construction industry. Subsequently, it constructs a novel performance model, resulting in the development of a practical computer application aimed at measuring and evaluating the performance of these projects.

This study aims to investigate the insights of soot formation such as rate of soot coagulation, rate of soot nucleation, rate of soot surface growth and soot surface oxidation in ethylene/hydrogen/nitrogen diffusion jet flame at standard atmospheric conditions, which is very challenging to capture even with highly sophisticated measuring systems such as Laser Induced Incandescence and Planar laser-induced fluorescence. The study also aims to investigate the volume of soot in the flame using soot volume fraction and to understand the global correlation effect in the formation of soot in ethylene/hydrogen/nitrogen diffusion jet flame.

A large eddy simulation (LES) was performed using box filtered subgrid-scale tensor. A filtered and residual component of the governing equations such as continuity, momentum, energy and species are resolved and modeled, respectively. All the filtered and residual components are numerically solved using the ILU method by considering PISO pressure–velocity solver. All the hyperbolic flux uses the QUICK algorithm, and an elliptic flux uses SOU to evaluate face values. In all the cases, Courant–Friedrichs–Lewy (CFL) conditions are maintained unity.

The findings are as follows: soot volume fraction (SVF) as a function of a flame-normalized length for three different Reynolds number configurations (Re = 15,000, Re = 8,000 and Re = 5,000) using LES; soot gas phase and particulate phase insights such as rate of soot nucleation, rate of soot coagulation, rate of soot surface growth and soot surface oxidation for three different Reynolds number configurations (Re = 15,000, Re = 8,000 and Re = 5,000); and soot global correction using total soot volume in the flame volume as a function of Reynolds number and Froude number.

The originality of this study includes the following: coupling LES turbulent model with chemical equilibrium diffusion combustion conjunction with semi-empirical Brookes Moss Hall (BMH) soot model by choosing C6H6 as a soot precursor kinetic pathway; insights of soot formations such as rate of soot nucleation, soot coagulation rate, soot surface growth rate and soot oxidation rate for ethylene/hydrogen/nitrogen co-flow flame; and SVF and its insights study for three inlet fuel port configurations having the three different Reynolds number (Re = 15,000, Re = 8,000 and Re = 5,000).

The purpose of this paper is to draw a map of the general features of epistemological and critical concerns in contemporary Islamic philosophy. This study will not be confined to the domain of academic philosophy or to those who are professionals in the field of philosophy.

The paper adopted the critical rational approach in dealing with contemporary Islamic philosophy in the Arab world. The scope will include scholars from different fields of epistemology who tried to present a “vision” of the attitude that should be adopted in facing the challenges of the age and the problems of the nation on the epistemological level or the political, economic and social levels.

There is a need for a philosophy of action and progress rather than a philosophy that is based on abstract ideas and theories and of words/rhetoric. The ethics required to accomplish this ought to identify the attributes of the citizen who can reach self-actualization through legitimate means based on a progress agenda with theoretical and philosophical foundations.

Because a critical rational approach can be dealt with from different perspectives, this paper will adopt the classification of the principal intellectual trends: the reformist, secular and liberal.

This paper covers a long time span to determine whether the philosophical projects have been effective.

This paper, which criticizes the philosophic projects that are theoretically unsound and that do not address real social problems (like poverty), argues the need for a philosophy of progress and action. This will lead to devising an agenda that addresses the challenges the society is facing and to finding alternative and creative solutions resulting in development.

This study aims to synthesise and characterise new reactive dyes based on thiazole derivatives which act as chromophoric moieties. These dyes were applied to cotton fabric, resulting in the dyed fabrics exhibiting good colour strength, light fastness and other fastness properties. The antibacterial activity of the dyed cotton fabric was evaluated against gram-negative and gram-positive bacteria.

The dyes were synthesised in two steps. First, the coupling compound was formed by adding H-acid solution to cyanuric chloride in an ice bath at pH 5 then adding 4-aminobenzenesulphonic acid portion-wise at room temperature and at pH 6-7. Second, different diazonium salts 4-phenylthiazol-2-amine (2a) and 4-(4-methoxyphenyl) thiazol-2-amine (2b) were coupled with the coupling compound at pH 5. The resultant monochlorotriazine (MCT)-reactive dyes (6a, 6b) were formed. The synthesised dyes were applied onto cotton fabric under typical exhaust dyeing conditions and their dyeing properties were investigated.

High antimicrobial activity, dye exhaustion and fixation yield on cotton fabric were recorded for each dye. All dyes showed high stability against washing, rubbing, perspiration and light fastness.

Dyeing of cotton fabric with these dyes which have higher fastness, higher exhaustion and higher antibacterial activity is considered one of the most important reactive dyes species.

The preparation procedure showed the synthesis of the novel MCT-reactive dyes derived from thiazole derivatives followed by the application of these dyes on cotton fabrics.

Use of reactive dyes will bring a number of benefits to society including higher fastness and higher antibacterial activity so, and these dyes can be used for dyeing cotton.

In this work, the new reactive dyes derived from thiazole derivatives were synthesised and their structures were confirmed by the analytical and spectral data. Such compounds are considered to be excellent reactive dyes with different colour shades and higher antibacterial activity.

Leadership is basically about influence and ability to cultivate followership. This chapter examined the nature of indigenous socio-political leadership in Africa using Zimbabwe, Sudan and Nigeria as caselets and compared this with the post-colonial or modern-day leadership realities. A survey was conducted among senior executives at Lagos Business School, Nigeria, with a sample size of 200 persons, to find out their perception of the African indigenous leadership system. An overwhelming 90% believe that culture plays a big role in shaping African leadership style. However, two-thirds of the respondents agreed that Africa lacks proper institutional structures to support good leadership, thus encouraging corruption (97% of the respondents) and non-accountability among the leaders. Also, only 5% thought cultural orientation was the reason why the African followers do not hold their leaders accountable. In other words, it is not in the African culture not to hold leaders accountable for their actions. So, what went wrong? We attempted a deeper look at the effect of colonial rule and the attendant militarisation of the African continent. Our conclusion is that the colonisation of the continent by Europe brought significant distortion to the traditional African indigenous leadership institutions and the psyche of the African leader and the followers alike. Post-colonial Africa has witnessed 133 recorded coups d’etat between 1952 and 2016. This chapter is recommended to all those who seek a deeper understanding of the nature of the African indigenous leadership practices and the factors that have shaped these over the years.