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The purpose of this paper is to extend the bridge scale method (BSM) developed for granular materials with only the solid phase to that taking into account the effects of wetting process in porous continuum. The granular material is modeled as partially saturated porous Cosserat continuum and discrete particle assembly in the coarse and fine scales, respectively.

Based on the mass and momentum conservation laws for the three phases, i.e. the solid skeleton, the pore water and the pore air, the governing equations for the unsaturated porous Biot-Cosserat continuum model in the coarse scale are derived. In light of the passive air pressure assumption, a reduced finite element model for the model is proposed. According to the decoupling of the fine and coarse scale calculations in the BSM, the unsaturated porous Cosserat continuum model using the finite element method and the discrete element model using the discrete element method for granular media are combined.

The numerical results for a 2D example problem of slope stability subjected to increasing rainfall along with mechanical loading demonstrate the applicability and performance of the present BSM. The microscopic mechanisms of macroscopic shear band developed in the slope are demonstrated.

Do not account for yet the effects of unsaturated pore water in the fine scale.

The novel BSM that couples the Biot-Cosserat porous continuum modeling and the discrete particle assembly modeling in both coarse and fine scales, respectively, is proposed to provide a micro-macro discrete-continuum two-scale modeling approach for numerical simulations of the hydro-mechanical coupling problems in unsaturated granular materials.

By applying a non‐parametric Malmquist Productivity Index to a sample of all post‐merger Malaysian banks over 2001‐2003, this paper attempts to investigate to what extent the inclusion of OBS items in the output definition of banks affect the estimated total factor productivity change indexes. It is found that the inclusion of OBS items results in an increase in estimated productivity levels for all banks under study. However, the impact seems to be the largest on technological change rather than efficiency change.

This study examined the economic and social impact of Malaysian universities on their communities from stakeholders' perspectives. It analysed whether university stakeholders' spending, human capital (HC) and knowledge exploration (KE) will impact aggregate income (AI), quality of life (QOL) and business growth (BG) in surrounding communities.

A survey was conducted among 540 university stakeholders from the southern, northern and eastern regions of Malaysia, representing the alumni, community and industry. Data were subjected to factor analysis using structural equation modelling (SEM).

Results showed that universities impacted communities' economic development and wellbeing, thereby fulfilling their community-related role.

This study addressed universities' role in communities' economic growth and social development. Universities' contributions towards communities can be improved through the proposed model, which suggests ways to maximise their impact. A more detailed study of a particular university is needed to identify other factors that can strengthen universities' impact, even at national and global levels.

The purpose of this paper is to create a computationally efficient reduced model (RM) for the moments of droplet size distribution (DSD) in condensing flow.

The kinetic equation (KE) exactly describes the time dependence of the DSD and can be regarded as the most rigorous representation of a system with condensation. Because of the typical wide range in droplet size, the KE requires excessive computational time and is not attractive for most practical applications. To reduce the overall computational efforts, a novel set of moment equations, derived from the KE has been proposed.

To demonstrate the simplicity and accuracy of the model, the authors employ a typical nucleation pulse experiment for which benchmark KE-solutions have also been computed. Comparison of predicted moments from both the RM and the KE approach reveals that the RM is capable of capturing the evolving feature of moments with reasonable accuracy.

The authors have created a novel reduced method for numerical computations of the lower-order moments of the DSD in condensing flow. Unlike the typical method of moments, the RM eliminates the need for assumptions on the shape of the distribution function and could estimate the moments at very low computational cost.

In order to meet the different quality of service (QoS) requirements of vehicle-to-infrastructure (V2I) and multiple vehicle-to-vehicle (V2V) links in vehicle networks, an efficient V2V spectrum access mechanism is proposed in this paper.

A long-short-term-memory-based multi-agent hybrid proximal policy optimization (LSTM-H-PPO) algorithm is proposed, through which the distributed spectrum access and continuous power control of V2V link are realized.

Simulation results show that compared with the baseline algorithm, the proposed algorithm has significant advantages in terms of total system capacity, payload delivery success rate of V2V link and convergence speed.

The LSTM layer uses the time sequence information to estimate the accurate system state, which ensures the choice of V2V spectrum access based on local observation effective. The hybrid PPO framework shares training parameters among agents which speeds up the entire training process. The proposed algorithm adopts the mode of centralized training and distributed execution, so that the agent can achieve the optimal spectrum access based on local observation information with less signaling overhead.

The increased awareness among consumers and strong competition have forced companies to put extra efforts and fulfill their social responsibility along with earning profits. The research aims to review corporate social responsibility (CSR)-related literature specifically determinants, outcomes and disclosure of CSR while adapting a comparative approach for developing and developed countries.

Based on theoretical frameworks of CSR, the authors have reviewed past studies conducted in past 10 years. While using keywords and synonyms, the databases such as JSTOR, Emerald, SpringerLink and ScienceDirect were used for searching impact factor and Scopus journals. Thematic analysis has been used as a method in the paper while identifying the key themes in study and presented them separately. Only those articles have been included which have key words in abstract. The review has been done while using logical process to improve inter-rater reliability. The key databased have been used to cover articles from multiple and diverse domains. The authors studied the key themes of literature found and identified the gaps. The paper has also incorporated the comments of authors who conducted credible studies.

It has been found that there are different determinants which lead the companies to involve in CSR practices in developing and developed countries. It has also been found that consumers are more aware about CSR in developed countries which effects the CSR decisions by firms. There is lack of literature available in developing states and researchers have been focused to conduct studies mainly developed countries such as in Europe and USA. Mostly the CSR behavior of companies has been linked with their financial and reputational benefits in empirical studies. There is large gap in literature on CSR involvement in small companies. The authors have developed and presented model which provides comparison of determinants leading toward CSR involvement by companies in developed and developing countries. Another framework has been developed which summarized all the factors which force the company to take part in CSR activities.

The study has made significant contribution toward research field and summarized the determinants based on social and economic factors of countries. The study also presented the comparison between CSR in developing and developed country which is valuable contribution by the authors. The study has also found lack of progress in theory development in this area which needs further attention by researchers. The authors have developed a model and framework which will contribute in field of CSR.

This is the review paper which provides integrated view of literature regarding determinants, outcomes and disclosure of CSR in developing countries while using a comparative approach.

The vehicle routing problem (VRP) is critical for the successful execution of logistics activities. However, there is strong evidence that efficiently solving the VRP is often complicated and requires more powerful – and possibly intelligent – support tools. In accordance with this necessity, the present study proposes a decision support system (DSS) applicable to the VRP, which includes both initial planning and replanning phases to support the real-time operations.

The proposed DSS lies at the basis of resilience thinking to provide a capacity to absorb and withstand the impact of disruptions, where resilience is connected with the factors of preparedness, flexibility and redundancy. These factors are approached in this study through a number of operational strategies in the reactive and proactive modes. The DSS includes a multi-layer perceptron neural network to predict changes that may arise in dynamic contexts, a modified k-means clustering algorithm to group customers with both static and dynamic attributes and two mixed-integer programming models to produce primary and alternate routing plans.

The research is motivated by the operational challenges faced by a collaborative networked clinical laboratory, which seeks to enhance efficiency and productivity in the daily management of medical sample collection and delivery through the implementation of increased automation. The findings reveal that centralized planning leads to heightened vulnerability in route planning and increased costs for replanning. Furthermore, the effectiveness of resilience-enhancement strategies varies based on the source and level of uncertainty.

The contributions of this paper are as follows: incorporating resilience thinking into the operational planning of logistics services, managing the decision-making of transport and collection companies through a DSS framework to ensure proper support to real-time operations, addressing the clustered VRP in a dynamic setting and adopting forecasting approaches to cover possible sources of dynamism.

This research aims to empirically investigate the impacts of product and international diversification strategies on firm-level inventory performance.

This study empirically examines the associations between product and international diversification strategies and inventory performance based on a sample of 64,124 observations across 7,367 US publicly traded firms between 1989 and 2019 from the COMPUSTAT Segment, Fundamental Annual and Fundamental Quarterly data files. We employ both linear and nonlinear regression models to perform our empirical analysis.

This research provides strong evidence that there exists a U-shaped relationship between unrelated product diversification and inventory level and a partially inverted U-shaped relationship between international diversification and inventory level. We also find a positive impact of related product diversification on inventory level, but there is no significant curvilinear relationship between related product diversification and inventory level.

Our research findings offer important insights into top management’s strategic planning for diversification strategies and operations manager’s inventory control policies to achieve the strategic fit between corporate diversification and inventory management.

Product and international diversification strategies not only play an essential role in the firm’s competitive advantage, but also have a significant influence on operations manager’s inventory decision. This research is among the first to systematically investigate how top management’s related product, unrelated product and international diversification strategies may have complex nonlinear impacts on inventory performance.

To modify a conventional evacuated tube, an improved asymmetric U-type evacuated tube (AUET) is proposed. This study aims to investigate the thermal and hydrodynamic performances of a modified tube and determine the optimal structural form.

Based on the variation of fluid proprieties with temperature, the formulated numerical model was validated and then deployed to investigate the natural circulation in the evacuated tubes. A dimensionless number was proposed to quantify the stratification effect. The influence of the degree of asymmetry of U-type evacuated tubes on the flow patterns, mass flow rate, temperature distribution, thermal stratification and energy conversion efficiency was studied.

When the degree of asymmetry is large, a higher velocity and better thermal stratification are achieved, thereby avoiding stagnant water at the bottom of the tubes simultaneously. Compared with the conventional evacuated tube, the improved evacuated tube exhibited a higher thermal efficiency.

The originally proposed AUET was proven to have better performance in avoiding stagnant water, reducing fluid mixing and improving the heat transfer efficiency.

The purpose of this study is to synthesize a semiconductor photocatalyst which responds to both UV light and visible light in removal of organic dyes.

ZnO nanoparticles were pre-synthesised via sol-gel method using zinc nitrate tetrahydrate and methanamine at 90°C for 20 h. Subsequently, the as-synthesised ZnO nanoparticles were filtered, washed and dried. To synthesize ZnO-MnO₂ core shell nanocomposites (CSNs), 2:3 M ratio of KMnO₄ and MnSO₄ solution was stirred for an hour. Next, ZnO nanoparticles were added into the solution. The solution was heated at 160°C for 3 h for the formation of ZnO-MnO₂ CSNs. The structural, optical and photocatalytic properties of ZnO-MnO₂ CSNs were characterised by field emission scanning electron microscope, transmission electron microscopy (TEM), X-ray diffractometer and PL spectroscopy, respectively.

The photodegradation efficiencies of rhodamine B (RhB) dye by ZnO-MnO₂ CSNs as photocatalysts are 87.1 per cent under UV irradiation and 76.6 per cent under visible light irradiation, respectively. Their corresponding rate constants are 0.016 min⁻¹ under UV irradiation and 0.013 min⁻¹ under visible light irradiation. It can be concluded that N-deethylation was the dominant step during the photodegradation of RhB dye as compared to cycloreversion. The ZnO-MnO₂ CSNs demonstrated good photostability after three consecutive runs.

ZnO-MnO₂ CSN photocatalyst which could response to UV and visible light in degradation of RhB dye was synthesised using sol-gel method. The analysis shows that N-deethylation was the key photodegradation mechanism of RhB by ZnO-MnO₂ CSN.