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The fibers are loaded by the cosine component of the external load, when a fiber fails, and due to the local load-sharing nature, its force is shared by surviving neighboring fibers. The results show that the system presents a greater resistance and toughness toward the applied load compared to the classical one.

In this paper, the authors adopt the dynamics of a local load-sharing fiber bundle model in two dimensions under an external load to study scaling law in failure process of composite materials with randomly oriented fibers. The model is based on the fiber bundle model where the fibers are randomly oriented. The system is different to the classical one where the fibers are arranged in parallel with the applied load direction.

The evolution time of the fraction of broken fiber is described by an exponential law with two characteristic times. The latter decrease linearly and exponentially respectively with both applied load and temperature.

Scaling behavior of the broken fiber numbers with the size system shows that the system exhibits a scaling law of Family–Vicsek model with universal exponents.

The purpose of the paper is to conduct a numerical and experimental investigation into the properties of nanofluids containing spherical nanoparticles of random sizes flowing through a porous medium. The study aims to understand how the thermophysical properties of the nanofluid are affected by factors such as nanoparticle volume fraction, permeability of the porous medium, and pore size. The paper provides insights into the behavior of nanofluids in complex environments and explores the impact of varying conditions on key properties such as thermal conductivity, density, viscosity, and specific heat. Ultimately, the research contributes to the broader understanding of nanofluid dynamics and has potential implications for engineering and industrial applications in porous media.

This paper investigates nanofluids with spherical nanoparticles in a porous medium, exploring thermal conductivity, density, specific heat, and dynamic viscosity. Studying three compositions, the analysis employs the classical Maxwell model and Koo and Kleinstreuer’s approach for thermal conductivity, considering particle shape and temperature effects. Density and specific heat are defined based on mass and volume ratios. Dynamic viscosity models, including Brinkman’s and Gherasim et al.'s, are discussed. Numerical simulations, implemented in Python using the Langevin model, yield results processed in Origin Pro. This research enhances understanding of nanofluid behavior, contributing valuable insights to porous media applications.

This study involves a numerical examination of nanofluid properties, featuring spherical nanoparticles of varying sizes suspended in a base fluid with known density, flowing through a porous medium. Experimental findings reveal a notable increase in thermal conductivity, density, and viscosity as the volume fraction of particles rises. Conversely, specific heat experiences a decrease with higher particle volume concentration.xD; xA; The influence of permeability and pore size on particle volume fraction variation is a key focus. Interestingly, while the permeability of the medium has a significant effect, it is observed that it increases with permeability. This underscores the role of the medium’s nature in altering the thermophysical properties of nanofluids.

This paper presents a novel numerical study on nanofluids with randomly sized spherical nanoparticles flowing in a porous medium. It explores the impact of porous medium properties on nanofluid thermophysical characteristics, emphasizing the significance of permeability and pore size. The inclusion of random nanoparticle sizes adds practical relevance. Contrasting trends are observed, where thermal conductivity, density, and viscosity increase with particle volume fraction, while specific heat decreases. These findings offer valuable insights for engineering applications, providing a deeper understanding of nanofluid behavior in porous environments and guiding the design of efficient systems in various industrial contexts.

The purpose of this paper is to present a study of the breaking process of composite membranes used in the water desalination. Temperature, fluid pressure and accumulate retained fluid are remarkable parameters, which are likely to damage these membranes.

In this paper, the authors adopt the dynamics of a fiber bundle model to investigate the breaking process of composite membranes with fibres distributed parallel to the direction of fluid flow. The model is based on the fiber bundle model where the fibres are randomly oriented.

The obtained results show that the increase in the parameters leads to an avalanche rupture of the membrane fibre and also increases its porosity. Lifetime membranes exhibit an exponential and power law vs. the parameters.

The accumulation of the retained fluid has a great effect on membranes than the temperature and fluid pressure.

The model incorporates key factors of membrane such as permeability and resistance, feed concentration, fluid viscosity and pressure differentials. Special emphasis is placed on the fouling mechanisms, including pore blockage and cake layer formation, which significantly impact the efficiency of the filtration process.

In this study, we present a numerical analysis of permeate flux through a membrane, focusing on the intricate dynamics of fouling phenomena. Utilizing the Langevin model, we simulate the permeation process to understand how various operational parameters affect the flux rates.

Our results demonstrate that fouling not only reduces the permeate flux but also alters the membrane’s hydraulic resistance over time. The results show that the increasing of the diffusion process on membrane reduces the clogging phenomenon. Hence, the increases of the transmembrane pressure reduce exponentially blocking pore process.

By analyzing these changes, we provide insights into optimizing membrane performance and developing strategies to mitigate clogging membrane. This research contributes to the field of membrane technology by enhancing our understanding of permeate flux behavior under fouling conditions and offering potential pathways for improving long-term operational sustainability.

The aim of the present paper is to investigate the behavior of collective motion of living biological organisms in the two-dimensional (2D) plane by adopting a new approach based on the use of Langevin dynamics. Langevin dynamics is a powerful tool to study these systems because they present a stochastic process due to collisions between their constituents.

In this paper, the dynamical properties and scaling behavior of self-propelled particles were studied numerically by using Langevin dynamics. These dynamics have been affected by the use of only the alignment zone of radius R.

The results indicated that the system’s velocity increases with time and reaches to finite value at the equilibrium phase.

This result is more consistent with that of Vicsek’s model. However, the system’s velocity decreases exponentially with the applied noise without taking the zero value for the highest noise value.

As well as, the crossover time of the growth kinetic system decreases exponentially with noise.

Scaling behavior has been checked for this system and the corresponding results prove that behavior scales with the same law of the one in Vicsek’s model but with different scaling exponents.

The phase transition observed in Vicsek’s model cannot be reproduced by the Langevin dynamics model, which describes more about the dynamical properties of self-propelled systems.

This study aims to systematically review the current academic literature on supply chain transparency (SCT) to explore the impact of SCT on firm performance and identify factors that influencing SCT-related practices.

This review follows the six steps and 14 decisions of conducting a systematic literature review (SLR) to comprehensively review 91 identified papers published between 2007 and 2024.

Based on the content analysis of the selected papers, this study summarizes the antecedents, practices, outcomes as well as potential barriers of SCT. We develop a conceptual framework from the descriptive and thematic findings to enrich the relevant aspects of SCT and propose some critical gaps and directions for future research.

This study links SCT with several outcomes of firm performance, with a particular focus on how SCT affects sustainability in terms of its economic, social, and environmental dimensions as well as supply chain resilience. It proposes potential avenues for enriching SCT in future research.

Nowadays, sustainable, clean, inclusive, innovative, and smart mobility in addition to urban transformation is required to achieve sustainable development as a path to preserve the world for future concerns and improve quality of life at the present, even to be kept up with growing citizens' needs. Mobility as an infrastructure component plays fundamental roles in urban transformation, and economic development. In this chapter, and based on the 5^th wave theory, related theories, models, and concepts, modern, clean, and inclusive mobility founded on high future of 4th technologies (which is called 5th technologies), digitalization, smartness, sustainability, and CSR 2.0 strategies is declared as proper clean mobility technologies to create sustainable and smart cities. Such smart cities are able to deal with challenges made by rapid, unplanned urbanization and globalization to achieve sustainable development. In this research, roles of inclusive and smart mobility systems as path to create modern and sustainable urban areas to make the world more sustainable and livable for living are declared. Literature reviews, case studies, interviews, and questionaries are applied as main methods to recognize inclusive and modern mobility and its roles in urban transformation to achieve sustainable development. This chapter is based on know-how and do-how of the author Prof. Hamid Doost on sustainability such as cooperating with Danish Sustainable Platforms Company, working with Erasmus Plus as an academic leader in Germany since 2017, cooperating with Copenhagen's former mayor and researching on sustainability. In this chapter, impact of sustainable mobility, sustainable buildings, and smart cities on CSR 2.0 and social responsibility, how these parameters improve sustainable development and sustainability in social responsibility, corporate social responsibility (CSR), and how social responsibility could influence humanities are explored.

This paper aims to create a new searchable 3D city model to help managers improve their decision-making.

This paper identifies data management basics and the key elements used in the new model design; it further analyzes five-city models, presents its findings and proposes analytical trends for the new model. It discusses the concepts underlying existing models, explains the benefit brought by the proposed model and demonstrates its robustness.

City systems can be interconnected, thanks to data digitization and the integration of new technologies into different management processes. Although there are several 3D city models available, none of those identified in this research can be queried for several sectors.

This model design can only be successfully realized in the presence of a public mandate. Potential limitations include information security risks and political non-acceptance.

The present work proposes a searchable and high performance model having the distinctive capacity to bring together city systems and perform real-time data analysis in order to extract important information needed to guide the city, and in the context of a global vision.

In this paper, a mixture of exponential and Rayleigh distributions in the proportions α and 1 − α and all the parameters in the mixture distribution are estimated based on fuzzy data.

The methods such as maximum likelihood estimation (MLE) and method of moments (MOM) are applied for estimation. Fuzzy data of triangular fuzzy numbers and Gaussian fuzzy numbers for different sample sizes are considered to illustrate the resulting estimation and to compare these methods. In addition to this, the obtained results are compared with existing results for crisp data in the literature.

The application of fuzziness in the data will be very useful to obtain precise results in the presence of vagueness in data. Mean square errors (MSEs) of the resulting estimators are computed using crisp data and fuzzy data. On comparison, in terms of MSEs, it is observed that maximum likelihood estimators perform better than moment estimators.

Classical methods of obtaining estimators of unknown parameters fail to give realistic estimators since these methods assume the data collected to be crisp or exact. Normally, such case of precise data is not always feasible and realistic in practice. Most of them will be incomplete and sometimes expressed in linguistic variables. Such data can be handled by generalizing the classical inference methods using fuzzy set theory.

The purpose of this paper is to study the effects of personal background and entrepreneurial attitudes on entrepreneurial intentions of Saudi Freshmen students of Al Imam Mohammad Ibn Saud Islamic University. After reviewing the literature and related theories on entrepreneurship, attitudes and intentions, this study provides a conceptual framework trying to identify the effects of most influential factors on individual’s intention to become an entrepreneur.

Through a survey study developed from previous empirical studies, the paper aims to investigate the significant elements of intentions from a sample of 103 students randomly selected. This study is both descriptive and analytical using correlations and multiple regressions.

The findings show that significant correlations among variables were found. The achievement and innovation attitudes are significant elements to entrepreneurial intentions. Students scored quite high on them, but, moderate on personal control and self-esteem attitudes. Students might have a real intention for starting their own businesses later that could be sustained during their studies at university. Additionally, entrepreneurs among relatives and entrepreneurship training were also the other significant elements to intentions.

Implications for future research are described and some pragmatic recommendations are provided to promote students’ entrepreneurial initiatives and behaviors at university.

The exploratory analysis suggests the need to develop more the awareness of students to entrepreneurship as potential career choice to help them to be active in the society.

In this paper, the Entrepreneurial Attitude Orientation model is validated for a Saudi university considered as a specific context. Broader reflections about a freshman student entrepreneurship as refocused research agenda is also considered by undertaking some new research and developing a comprehensive and contextual framework.