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The present investigation deals with the analysis of the performance of twin thermoacoustic prime mover (TAPM) which are measured in terms of frequency and pressure amplitude by varying the parameters such as temperature gradient along the length of stack and the operating pressures of fluid medium argon using CFD simulation. With the help of CFD researchers and Engineers can evaluate the performance of a wide range of thermoacoustic systems on the computer without the time, expense, and disruption required to make actual changes onsite (stack) which is tedious to fabricate.

For the present simulation, the operating pressures of argon such as 1bar, 3bar and 5bar, and the temperature gradient is varied from 600K to 1400K with the regular intervals of each 200K. The geometry of twin TAPM is created using GAMBIT processor, and the simulation is carried out using FLUENT. The geometrical parameters of twin TAPM are kept constant throughout the simulation. The results for frequency and pressure amplitude obtained from the CFD simulation of twin TAPM for various temperature gradient and operating pressures are analysed and reported.

The computational results of twin thermoacoustic prime mover shows an increase in pressure amplitude with an increase in the temperature gradient and also it increases with an increase in operating pressures of the fluid medium. The parameter operating pressures of the working fluid medium and the stack hot end temperature has no significant effect on the output, frequency.

Though several experimental works had been published based on the twin thermoacoustic prime mover, an attempt has been made in the present investigation for the first time to estimate the performance of twin thermoacoustic prime mover using CFD package (ANSYS-FLUENT) by varying temperature gradient. The temperature gradient and operating pressures were varied and the performance of twin thermoacoustic prime mover was measured in terms of frequency and pressure amplitude.

This study aims to investigate the performance characteristics of an externally adjustable bearing with multiple pads in steady state conditions. The proposed adjustable bearing geometry can effectively control the hydrodynamic operation in bearing clearances by adjusting the pads in radial and tilt directions. These pad adjustments have a significant role in improving the bearing characteristics such as load capacity, attitude angle, side leakage, friction variable and Sommerfeld number, which will be analysed in this paper.

The adjustable bearing is designed with circumferentially spaced four bearing pads subjected to similar radial and tilt adjustments. Tilt angles are applied along the leading edges of bearing pads. A modified film thickness equation is used to incorporate the pad adjustments and accurately predict the variation in film profile. Finite difference approximation is adopted to solve the Reynolds equation and discretize the fluid film domain.

For negative radial and tilt adjustments, higher hydrodynamic pressures are generated in bearing clearances, which increases the bearing load capacity at different eccentricity ratios. From comparative analysis for different pad adjustments, superior bearing performance is observed for bearing pads under negative radial and negative tilt adjustments.

This research presents a detailed theoretical approach to analyse the performance capability of a four pad adjustable bearing geometry, which is not available in literatures. Improved bearing performances with negative pad adjustments can attract bearing designers to implement the proposed adjustability-bearing concept in rotating machineries.

This research is designed to meet two research objectives: firstly, to weigh up the criteria of Internet of Things (IoT) adoption in warehousing startups; secondly, to rank warehousing startups on the basis of benefits they derive from IoT adoption catering to an unorganized sector in the food supply chain.

A blend of analytic hierarchy process (AHP) and complex proportional assessment (COPRAS) methods of multi-criteria decision-making techniques were applied. AHP determined the weights of various criteria using pairwise comparison, and COPRAS technique ranked the 10 warehousing startups on account of performance indicators. The study has been conducted at the warehousing startups of Bangalore, a hub of food warehousing startups.

The critical findings of the study revealed that these food warehouse startups attain improved productivity in terms of enhancing efficiency when implemented with IoT adoption. When evaluated using both AHP and COPRAS techniques, the combined results show WH5 as the best performing and WH10 as the least performing warehouse startups.

Warehouses that are embarking on their business opportunity in food storage can strategize to leverage the benefits of IoT in terms of food safety and security, capacity planning, layout design, space utilization and resilience.

Despite the numerous research works on food supply chain, the research on IoT in warehousing startups is limited. The rankings for the 10 food warehousing startups integrated with IoT using AHP-COPRAS approaches are the novelty of this work.

This study provides a country-specific and sector-wide study of campus sustainability. Campus sustainability is a key consideration for the higher education (HEI) sector, and campus sustainability officers and managers manage its reporting and planning. Global and country-specific studies to date have focussed on individual organisation narratives, interviews with faculty and management and content analysis of reports and plans. Findings show wide divergence on scope and scale of formalised planning and reporting, few references to sustainability officers and managers’ perspectives and limited reference to organisational theory to explain tactics and strategies adopted. As a result, there are a few country-specific and sector-wide studies. The purpose of this paper is to address the scarcity of country-specific and sector-wide studies into campus sustainability practices in HEI by combining qualitative and quantitative analysis.

The authors provide the first sector-wide overview of formal campus sustainability commitments for the Australian public sector HEI (n = 41) in terms of several key indicators – plans, reports and other indicators. Second, the authors use reflexive thematic analysis of interviews (n = 21) with current and former sustainability officers and managers to examine sector organisational reasons for such variation. Third, the authors analyse HEI sector isomorphism and divergence on planning and reporting of campus sustainability from the perspective of institutional theory of organisations.

This study finds some convergence on the need for plans, reporting and other engagement elements, albeit without any sector-wide standards being followed. The authors observe a trend towards carbon-neutral (CN) declarations before 2030 although with nuances on emissions scope and increasing inclusion of renewable energy. Interviews identify a range of strategies and tactics adopted for campus sustainability relative to internal and external organisational pressures. Overall, the sector still exhibits weak institutionalisation of sustainability.

This study interviews a specific and limited cohort (n = 21) and presents an overview of sector reporting, planning and target setting although not a detailed content analysis. Other interview cohorts may have different views on the strategic and tactical purposes of reporting practices, and more in-depth analysis of formal plans and reports should be conducted in the future.

This study concludes that the Australian HEI sector should consider greater public transparency of its data and reporting actions. Common standards and a benchmarking platform for the sector would improve overall engagement with all internal and external stakeholders. At present, the HEI sector’s message to its key internal and external stakeholders is mixed and needs to change towards a more in-depth institutionalisation of sustainability on campus.

Particular insights are the value of organisational strategies and tactics as an interpretive framework for HEI campus sustainability and how interviewees attribute sector competitors and self-different motives and tactics. Albeit limited, this is the first mapping of sector approaches to sustainability reporting and planning.

This study explores the immobilisation of enzymes within porous catalysts of various geometries, including spheres, cylinders and flat pellets. The objective is to understand the irreversible Michaelis-Menten kinetic process within immobilised enzymes through advanced mathematical modelling.

Mathematical models were developed based on reaction-diffusion equations incorporating nonlinear variables associated with Michaelis-Menten kinetics. This research introduces fractional derivatives to investigate enzyme reaction kinetics, addressing a significant gap in the existing literature. A novel approximation method, based on the independent polynomials of the complete bipartite graph, is employed to explore solutions for substrate concentration and effectiveness factor across a spectrum of parameter values. The analytical solutions generated through the bipartite polynomial approximation method (BPAM) are rigorously tested against established methods, including the Bernoulli wavelet method (BWM), Taylor series method (TSM), Adomian decomposition method (ADM) and fourth-order Runge-Kutta method (RKM).

The study identifies two main findings. Firstly, the behaviour of dimensionless substrate concentration with distance is analysed for planar, cylindrical and spherical catalysts using both integer and fractional order Michaelis-Menten modelling. Secondly, the research investigates the variability of the dimensionless effectiveness factor with the Thiele modulus.

The study primarily focuses on mathematical modelling and theoretical analysis, with limited experimental validation. Future research should involve more extensive experimental verification to corroborate the findings. Additionally, the study assumes ideal conditions and uniform catalyst properties, which may not fully reflect real-world complexities. Incorporating factors such as mass transfer limitations, non-uniform catalyst structures and enzyme deactivation kinetics could enhance the model’s accuracy and broaden its applicability. Furthermore, extending the analysis to include multi-enzyme systems and complex reaction networks would provide a more comprehensive understanding of biocatalytic processes.

The validated bipartite polynomial approximation method presents a practical tool for optimizing enzyme reactor design and operation in industrial settings. By accurately predicting substrate concentration and effectiveness factor, this approach enables efficient utilization of immobilised enzymes within porous catalysts. Implementation of these findings can lead to enhanced process efficiency, reduced operating costs and improved product yields in various biocatalytic applications such as pharmaceuticals, food processing and biofuel production. Additionally, this research fosters innovation in enzyme immobilisation techniques, offering practical insights for engineers and researchers striving to develop sustainable and economically viable bioprocesses.

The advancement of enzyme immobilisation techniques holds promise for addressing societal challenges such as sustainable production, environmental protection and healthcare. By enabling more efficient biocatalytic processes, this research contributes to reducing industrial waste, minimizing energy consumption and enhancing access to pharmaceuticals and bio-based products. Moreover, the development of eco-friendly manufacturing practices through biocatalysis aligns with global efforts towards sustainability and mitigating climate change. The widespread adoption of these technologies can foster a more environmentally conscious society while stimulating economic growth and innovation in biotechnology and related industries.

This study offers a pioneering approximation method using the independent polynomials of the complete bipartite graph to investigate enzyme reaction kinetics. The comprehensive validation of this method through comparison with established solution techniques ensures its reliability and accuracy. The findings hold promise for advancing the field of biocatalysts and provide valuable insights for designing efficient enzyme reactors.

A process that does not include the customer's value may not be effective in providing care. This study aimed to identify value and waste in an emergency department (ED) patient flow process from a patient and clinician perspective.

A qualitative case study was conducted in an ED in Trinidad and Tobago. Observations and informal conversational interviews with clinicians (n = 33) and patients (n = 50) explored patient flow, value and waste. Thematic analysis was used to create a framework on valuable and wasteful aspects in the ED patient flow process.

Valuable aspects led to direct improvements in the patient's health or an exchange of information in the process. Wasteful aspects were those with no patient activity, no direct ED clinical involvement, or resulted in a perceived inappropriate use of ED resources. However, there was a disparity in responses between clinicians and patients with clinicians identifying more features in the process.

The single case study design limits the generalizability of findings to other settings. This study did not specifically explore the influence of age and gender on what mattered to patients in ED services. Future studies would benefit from exploring whether there are any age and gender differences in patient perspectives of value and waste. Further research is needed to validate the usefulness of the framework in a wider range of settings and consider demographic factors such as age and gender.

The study has produced a framework which may be used to improve patient flow in a way that maximized value to its users. A collaborative approach, with active patient involvement, is needed to develop a process that is valuable to all. The single case study design limits the generalizability of findings to other settings.

Qualitative methods were used to explicitly explore both value and waste in emergency department patient flow, incorporating the patient perspective. This paper provides an approach that decision makers may use to refine the ED patient flow process into one that flows well, improves quality and maximizes value to its users.

The purpose of this paper is to propose a stable high-order absorbing boundary condition (ABC) based on new continued fraction for scalar wave propagation in 2D and 3D unbounded layers.

The ABC is obtained based on continued fraction (CF) expansion of the frequency-domain dynamic stiffness coefficient (DtN kernel) on the artificial boundary of a truncated infinite domain. The CF which has been used to the thin layer method in [69] will be applied to the DtN method to develop a time-domain high-order ABC for the transient scalar wave propagation in 2D. Furthermore, a new stable composite-CF is proposed in this study for 3D unbounded layers by nesting the above CF for 2D layer and another CF.

The ABS has been transformed from frequency to time domain by using the auxiliary variable technique. The high-order time-domain ABC can couple seamlessly with the finite element method. The instability of the ABC-FEM coupled system is discussed and cured.

This manuscript establishes a stable high-order time-domain ABC for the scalar wave equation in 2D and 3D unbounded layers, which is based on the new continued fraction. The high-order time-domain ABC can couple seamlessly with the finite element method. The instability of the coupled system is discussed and cured.

The Analytical Hierarchy Process (AHP), a multicriteria decision support system that has been successfully applied to numerous decision-making situations, has been applied to patient assessment. The AHP was used with Timeslips™, a group storytelling program that encourages creative expression among dementia patients, to determine the optimal scale for pre and post assessment among the nine most common agitation and anxiety scales. The AHP used the six criteria identified by qualitative assessment of the nine scales: (1) validity/reliability, (2) observation period, (3) training required, (4) time to administer, (5) most appropriate administrator, and (6) accessibility/cost. The AHP indicated that the Overt Agitation & Anxiety Scale was optimal for use with Timeslips; the process and results are discussed.