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The increasing accumulation of synthetic plastic waste in oceans and landfills, along with the depletion of non-renewable fossil-based resources, has sparked environmental concerns and prompted the search for environmentally friendly alternatives. Biodegradable plastics derived from lignocellulosic materials are emerging as substitutes for synthetic plastics, offering significant potential to reduce landfill stress and minimise environmental impacts. This study highlights a sustainable and cost-effective solution by utilising agricultural residues and invasive plant materials as carbon substrates for the production of biopolymers, particularly polyhydroxybutyrate (PHB), through microbiological processes. Locally sourced residual materials were preferred to reduce transportation costs and ensure accessibility. The selection of suitable residue streams was based on various criteria, including strength properties, cellulose content, low ash and lignin content, affordability, non-toxicity, biocompatibility, shelf-life, mechanical and physical properties, short maturation period, antibacterial properties and compatibility with global food security. Life cycle assessments confirm that PHB dramatically lowers CO₂ emissions compared to traditional plastics, while the growing use of lignocellulosic biomass in biopolymeric applications offers renewable and readily available resources. Governments worldwide are increasingly inclined to develop comprehensive bioeconomy policies and specialised bioplastics initiatives, driven by customer acceptability and the rising demand for environmentally friendly solutions. The implications of climate change, price volatility in fossil materials, and the imperative to reduce dependence on fossil resources further contribute to the desirability of biopolymers. The study involves fermentation, turbidity measurements, extraction and purification of PHB, and the manufacturing and testing of composite biopolymers using various physical, mechanical and chemical tests.

The purpose of this paper is to propose a model for a target searching problem in a two-dimensional region with time constraints. The proposed model facilitates the search operation by minimizing the mission time and fuel usage, and the search operation is performed by a set of agents divided into a number of groups.

The authors have applied optimization techniques, Cartesian product, inclusion–exclusion principle, cooperative strategy, Shapley value, fuzzy Shapley function and Choquet integral to model the problem.

The proposed technique optimizes the placement of base stations that minimizes the sortie length of the agents. The results show that the cooperative strategy outperforms the non-cooperative strategy. The Shapley values quantify the rewards of each group based on their contributions to the search operation, whereas the fuzzy Shapley values determine the rewards of each group based on their contributions and level of cooperation in the search operation.

The proposed model can be applied to model many real-time problems such as patrolling in international borders, urban areas, forests and managing rescue operations after natural calamities, etc. Therefore, defence organizations, police departments and other operation management sectors will be benefitted by applying the proposed approach.

To the best of the authors’ knowledge, determining the optimal locations of base stations in a region is not explored in the existing works on target searching problems with fuel constraints. The proposed approach to cooperatively search the targets in a region is new. Introducing the Shapley function and fuzzy Shapley function is a novel idea to quantify the rewards of each group based on their contributions and level of cooperation in the search operation. This paper addresses these unexplored areas.

The purpose of this paper is to propose a model for a two-agent multi-target-searching scenario in a two-dimensional region, where some places of the region have limited resource capacity in terms of the number of agents that can simultaneously pass through those places and few places of the region are unreachable that expand with time. The proposed cooperative search model and Petri net model facilitate the search operation considering the constraints mentioned in the paper. The Petri net model graphically illustrates different scenarios and helps the agents to validate the strategies.

In this paper, the authors have applied an optimization approach to determine the optimal locations of base stations, a cooperative search model, inclusion–exclusion principle, Cartesian product to optimize the search operation and a Petri net model to validate the search technique.

The proposed approach finds the optimal locations of the base stations in the region. The proposed cooperative search model allows various constraints such as resource capacity, time-dependent unreachable places/obstacles, fuel capacities of the agents, two types of targets assigned to two agents and limited sortie lengths. On the other hand, a Petri net model graphically represents whether collisions/deadlocks between the two agents are possible or not for a particular combination of paths as well as effect of time-dependent unreachable places for different combination of paths are also illustrated.

The problem addressed in this paper is similar to various real-time problems such as rescue operations during/after flood, landslide, earthquake, accident, patrolling in urban areas, international borders, forests, etc. Thus, the proposed model can benefit various organizations and departments such as rescue operation authorities, defense organizations, police departments, etc.

To the best of the authors’ knowledge, the problem addressed in this paper has not been completely explored, and the proposed cooperative search model to conduct the search operation considering the above-mentioned constraints is new. To the best of the authors’ knowledge, no paper has modeled time-dependent unreachable places with the help of Petri net.

Carbon dioxide (CO₂) has attracted special scientific interest over the last years mainly because of its relation to climate change and indoor air quality. Except for this, CO₂ can be used as an indicator of food freshness, patients’ clinical state and fire detection. Therefore, the accurate monitoring and controlling of CO₂ levels are imperative. The development of highly sensitive, selective and reliable sensors that can efficiently distinguish CO₂ in various conditions of temperature, humidity and other gases’ interference is the subject of intensive research with chemi-resistive zinc oxide (ZnO)-based sensors holding a privileged position. Several ZnO nanostructures have been used in sensing applications because of their versatile features. However, the deficient selectivity and long-term stability remain major concerns, especially when operating at room temperature. This study aims to encompass an extensive study of CO₂ chemi-resistive sensors based on ZnO, introducing the most significant advances of recent years and the best strategies for enhancing ZnO sensing properties.

An overview of the different ZnO nanostructures used for CO₂ sensing and their synthesis methods is presented, focusing on the parameters that highly affect the sensing mechanism and, thus, the performance of CO₂ sensors.

The selectivity and sensitivity of ZnO sensors can be enhanced by adjusting various parameters during their synthesis and by doping or treating ZnO with suitable materials.

This paper summarises the advances in the rapidly evolving field of CO₂ sensing by ZnO sensors and provides research directions for optimised sensors in the future.

The study aims to review the literatures on the effect of fiber length on the mechanical response of natural fiber composite will help the researchers to know about the perspective of the various natural fibers in making of composite concerning fiber length. The review summarized the work of the other researchers, thereby unambiguously précised suitability of a specific natural fiber for a matrix in use. Thus, one can identify the use of the same fibers–matrix combination to obtain composites with different properties with the control of fiber/matrix interface.

The review work proposes a new kind of diagrammatic representation that expresses the influence of fiber length. This work has not been explored before in this specific format. The chronology of work may help to select natural fibers for use in composites for a specific matrix.

The length of the fiber perception in terms of “critical” length decides the need for pre-treatment process of natural fiber to improve shear stress at the interface for various matrices.

The current review paper attempts to shed light on the association between the fiber length of natural fiber and the mechanical response of natural fiber composite. Moreover, it probes the concepts of critical fiber length as a persuadable factor.

The purpose of this investigation is to determine the nature of the flow field, temperature distribution and heat and mass transfer in a triangular solar collector enclosure with a corrugated bottom wall in the unsteady condition numerically.

Non-linear governing partial differential equations (i.e. mass, momentum, energy and concentration equations) are transformed into a system of integral equations by applying the Galerkin weighted residual method. The integration involved in each of these terms is performed using Gauss’ quadrature method. The resulting non-linear algebraic equations are modified by the imposition of boundary conditions. Finally, Newton’s method is used to modify non-linear equations into the linear algebraic equations.

Both the buoyancy ratio and thermal Rayleigh number play an important role in controlling the mode of heat transfer and mass transfer.

Calculations are performed for various thermal Rayleigh numbers, buoyancy ratios and time periods. For each specific condition, streamline contours, isotherm contours and iso-concentration contours are obtained, and the variation in the overall Nusselt and Sherwood numbers is identified for different parameter combinations.

The recent decade has described the role of HR practitioners as more strategic to advance in environmental management (EM), technology and change management competencies. The study aims to identify the HR professionals' changing strategies and challenges and barriers in sustainability performance (SP) through green HRM, which have become an emerging topic.

Data collection was conducted through six semi-structured face-to-face interviews with senior HR representatives through purposive sampling. The grounded theory (GT) method was applied, followed by an iterative process for codes and themes.

The results indicated the highly significant challenges and barriers (C&B) proposing a 5 × 4 framework in adopting GHRM practices. Examples of the challenges included (1) lack of knowledge, orientation and awareness; (2) corporate social responsibility as an integral part of the organization strategy; (3) environmental concerns internally required from top-bottom and bottom-top approach; (4) budget and cost that remain an issue for the top management, and; (5) HR department's responsibility to build competencies for their entire team.

The findings help the top management and policymakers maintain a balance between economic, environmental and social sustainability performance agendas. Furthermore, the environmental goals and values of the hotel are key ingredients in seeking the solution to environmental sustainability, which requires continuous training programs to enhance awareness at all levels.

The results are presented as future directions to enrich the literature and make significant contributions to the existing body of knowledge. Moreover, the research benefits the managers from the results intended in accomplishing sustainable development approaches.

This paper aims to evaluate the mechanical properties and slurry erosion behaviour of 10TiO2-Cr2O3 coated turbine steel.

Slurry erosion experiments were performed on the coated turbine steel specimens using slurry erosion test rig under accelerated conditions such as rotational speed, average particle size and slurry concentration. Surface roughness tester, Vickers microhardness tester and scanning electron microscope were used to analyse erosion mechanism.

Under all experimental conditions, 10TiO2-Cr2O3 coated steel showed better slurry erosion resistance in comparison with Al2O3 coated and uncoated steel specimens. Each experimental condition indicated a significant effect on the erosion rate of both coatings and uncoated steel. The surface analysis of uncoated eroded specimen revealed that plastic deformation, ploughing and deep craters formation were the reasons for mass loss, whereas microchipping, ploughing and microcutting were the reasons for mass loss of coated specimens.

The present investigation provides novel insight into the comparative slurry erosion performance of high velocity oxy fuel deposited 10TiO2-Cr2O3 and Cr2O3 coatings under various environmental conditions. To form modified powder, 10 Wt.% TiO2 was added to 90 Wt.% Cr2O3.

Ready-to-drink (RTD) tea beverages are widely consumed worldwide and play a prominent role in people’s daily lives, yet few studies have investigated the motivation of RTD tea beverage consumers as well as their underlying attitudes and desires. The purpose of this paper is to explore why these attributes are motivational factors by focussing on the attributes of RTD tea beverage products that motivate consumers to purchase RTD tea.

The attribute-consequence-value model of the means-end chain approach was employed to investigate consumer motivations for purchasing RTD tea beverages. Data were collected through a qualitative face-to-face survey of 153 RTD tea beverage consumers in Taiwan.

The results indicate that consumers purchase RTD tea beverages because the taste, flavor, packaging, and ingredients (attributes) satisfy their desire to drink RTD tea and fulfill the benefits of being delicious to drink, possessing thirst-quenching properties, and possessing health-promoting properties (perceived consequences), thereby fulfilling their ideal goal of experiencing enjoyment (perceived product value).

The findings may serve as a reference for producers of RTD tea beverages regarding product development and marketing.

This paper aims to develop a framework for critical information infrastructure (CII) protection in smart government, an alternative measure for common cybersecurity frameworks such as NIST Cybersecurity Framework and ISO 27001. Smart government is defined as the government administration sector of CII due to its similarity as a core of smart technology.

To ensure the validity of the data, the research methodology used in this paper follows the predicting malfunctions in socio-technical systems (PreMiSTS) approach, a variation of the socio-technical system (STS) approach specifically designed to predict potential issues in the STS. In this study, PreMiSTS was enriched with observation and systematic literature review as its main data collection method, thematic analysis and validation by experts using fuzzy Delphi method (FDM).

The proposed CII protection framework comprises several dimensions: objectives, interdependency, functions, risk management, resources and governance. For all those dimensions, there are 20 elements and 41 variables.

This framework can be an alternative guideline for CII protection in smart government, particularly in government administration services.

The author uses PreMiSTS, a socio-technical approach combined with thematic analysis and FDM, to design a security framework for CII protection. This combination was designed as a mixed-method approach to improve the likelihood of success in an IT project.