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In this paper, temperature distribution and fin efficiency in a moving porous fin have been discussed. The heat transfer equation is formulated by using Darcy's model. Heat transfer coefficient and thermal conductivity vary with temperature. The surface emissivity of the fin varies with temperature as well as with wavelength. Thermal conductivity is taken as a linear and quadratic form of temperature. The entire analysis of the paper is presented in non-dimensional form.

In this study, a new mathematical model is investigated. The novelty of this model is surface emissivity which is considered temperature and wavelength dependent. Another interesting point is the addition of porous material. The Legendre wavelet collocation method has been used to solve the nonlinear heat transfer equation. Numerical simulations are carried out in MATLAB software.

An attempt has been made to discuss temperature distribution in the presence of porosity and wavelength-temperature-dependent surface emissivity. The effect of various parameters on temperature has been discussed, including thermal conductivity, emissivity, convection-radiation, Peclet number, sink temperature, exponent “n” and porosity. Fin efficiency is also calculated for some parameters. According to the study, heat transfer rate increases with higher radiation-convection, emissivity, wavelength and porosity parameters.

The numerical results are carried out by using the Legendre wavelet collocation method, which has been compared with exact results in a particular case and found to be in good agreement. The percent error is calculated to find the error between the current method and the exact result. A comparison of the obtained results with the previous data is presented to validate the numerical results.

This paper aims to design and analyze a controlled magnetorheological damper-based ankle-foot prosthesis prototype.

The ankle-foot prostheses prototype is proposed using the lightweight three dimensional (3 D)-printed parts, MR damper and digital servomotor. Initially, the computer-aided design (CAD) model of the prosthetic foot, leaf spring, retention spring and the various connecting parts required to connect the pylon and damper actuator assemblies are designed using CAD software. Later, the fused deposition modeling 3 D printer-based technique prints a prosthetic foot and other connecting parts using Acrylonitrile Butadiene Styrene filament. The prototype consists of two control parts: the first part controls the MR actuator that absorbs the impacts during walking. The second part is the control of the electric actuator intended to generate the dorsiflexion and plantar flexion movements. Finally, the prototype is tested on a transtibial amputee under the supervision of a prosthetist.

The ANalysis SYStems software-based analysis has shown that the prosthetic foot has a factor of safety values between 4.7 and 8.7 for heel strike, mid-swing and toe-off; hence, it is safe from mechanical failure. The designed MR damper-based ankle-foot prosthesis prototype is tested on an amputee for a level-ground walk; he felt comfortable compared to his passive prosthesis.

The design of an MR damper-based prosthesis prototype offers a better dynamic range for locomotion than passive prostheses. It reduces the injuries and provides relief to the transtibial amputees.

The purpose of this paper is to understand the key challenges, approaches and lessons of the higher educational institutions (HEIs) in the context of COVID-19.

A survey was conducted to understand the key challenges being faced by the HEIs around the world during the ongoing COVID-19 pandemic. A total of 150 responses were collected from 65 universities, located in 29 countries.

The results show that 47% of respondents with defined universities believe their institutions lacked a permanent or dedicated emergency management office, and 41% said their HEIs lacked a general business continuity plan for an emergency. In universities with BCPs, 33% of the plans do not cover biological hazards and pandemic risk management, and 60% of the plans did not include conducting any advanced simulation exercises. More than 70% the responded said their instruction, information sharing and decision-making process were timely and open. The major challenges identified were a lack of adequate preparedness for pandemic and of pandemic-specific advanced simulation exercises. The next major challenges were the change in the mode of teaching to online lectures and working from home. Based on these challenges, a set of short- and long-term recommendations were proposed.

This was the first survey in academic institutions in post COVID-19 context. The findings will be useful for preparing for biological and other related hazards.

Currently, waste is regarded as a symptom of inefficiency. The generation of waste is a human activity, not a natural one. Currently, landfilling and incinerating wastes are common waste management techniques; but the use of these methods, in addition to wasting raw materials, causes damage to the environment, water, soil, and air. In the new concept of “Zero Waste” (ZW), waste is considered a valuable resource. A vital component of the methodology includes creating and managing items and procedures that limit the waste volume and toxicity and preserve and recover all resources rather than burning or burying them. With ZW, the end of one product becomes the beginning of another, unlike a linear system where waste is generated from product consumption. A scientific treatment technique, resource recovery, and reverse logistics may enable the waste from one product to become raw material for another, regardless of whether it is municipal, industrial, agricultural, biomedical, construction, or demolition. This chapter discusses the concept of zero landfills and zero waste and related initiatives and ideas; it also looks at potential obstacles to put the ZW concept into reality. Several methods are presented to investigate and evaluate efficient resource utilization for maximum recycling efficiency, economic improvement through resource minimization, and mandatory refuse collection. One of the most practical and used approaches is the Life Cycle Assessment (LCA) approach, which is based on green engineering and the cradle-to-cradle principle; the LCA technique is used in most current research, allowing for a complete investigation of possible environmental repercussions. This approach considers the entire life cycle of a product, including the origin of raw materials, manufacturing, transportation, usage, and final disposal, or recycling. Using a life cycle perspective, all stakeholders (product designers, service providers, political and legislative agencies, and consumers) may make environmentally sound and long-term decisions.

This paper aims to propose guidelines for public sector managers in assessing the impact of outsourcing on business continuity (BC) strategies. This paper evaluated how public managers from the state of Pernambuco, Brazil, perceive outsourcing, considering BC and how it relates to the outsourcing of services and activities.

Theoretical lenses of outsourcing and BC were used to derive the study hypotheses. A questionnaire was drawn up to collect information to test the hypotheses. To test the proposed hypotheses, binary logistic regression was used through an empirical analysis of a sample of 51 Brazilian public managers.

This study found that when the public sector suffers from negative impacts of financial restrictions, outsourced services are the first ones to receive the negative impacts. This has had an adverse impact on BC in the public sphere. On the other hand, the authors verified that the public sphere’s capacity for resilience and the existence of specific methodologies to support public managers in outsourcing decision-making can contribute to BC.

This study assists public organizations to take advantage of internal outsourced services in the best possible way, making better use of public resources, gaining social legitimacy and legitimacy also in the provision of public services. However, each public sector can present different risks of non-continuity, and this aspect could not be considered in this research as well.

This study is a pioneer in highlighting the relationships between outsourcing strategies and BC in public services in Brazil. Through the guidelines discussed in this study, public managers could develop a more effective response to the implications of post-outsourcing budget constraints. In addition, the findings of this paper add to an understanding of the importance of business strategies for public services continuity and seek to help reduce uncertainties and better inform the government decision-making process.

The purpose of this paper is to develop government and community-level critical thinking, planning, and action for improving community disaster resilience by reporting a study that sought to evaluate the possibility of using the Torrens Resilience Institute Australian Community Disaster Resilience (CDR) Scorecard in the Malaysian context.

A participatory action research approach (done in 2015) encouraged key people involved in managing the 2014 Kelantan floods in Malaysia’s north-east to participate in discussions about, and self-testing of, the CDR Scorecard to measure and improve their communities’ disaster resilience.

The CDR Scorecard can be useful in the Malaysian community context, with some modifications. Self-testing revealed that participating communities need to strengthen their disaster resilience through better communication, cross-community cooperation, maximizing opportunities to compare their plans, actions and reactions with those reported in research publications, and aligning their community disaster management with reported best practice internationally while acknowledging the need to adapt such practice to local contexts.

There is a need for a Malaysia-wide, simple-to-use, standardized disaster resilience scorecard to improve communities’ quality, self-efficacy, and capability to facilitate improved disaster resilience.

The adaptation of Australian CDR Scorecard for used in the country.

Awareness of CDR level will enhance community and government preparedness, mitigation, and responses to flood disaster.

This project is the first of its kind in Malaysia. It provides an example of the possibilities of using the CDR Scorecard globally in the form of a context-specific toolkit. The engagement of key people in the community in self-testing the Scorecard provides genuine, on-the-ground, real life data, giving others an understanding of local assessment of each community’s resilience level.

As educational institutes began to address the challenges posed by COVID-19, e-learning came to the foreground as the best bet left. This study is in quest of revealing engineering student's perceptions of the available e-learning platforms, thus surfacing the underlying bottlenecks. Further, it aims at providing solutions that would help enhance the e-learning experience not only in pandemic times but also in the long run.

This holistic research begins with a comprehensive comparative study about the available e-learning platforms, followed by a primary data analysis through an online survey of 364 engineering students from various colleges and branches. The collected data was analyzed to detect bottlenecks in online learning and suggestions are given for solving some challenges.

On a five-point Likert scale, the available e-learning platforms garnered ratings ranging from 2.81 to 3.46. Google meet was the most preferred platform. However, with a net promoter score (NPS) of 30.36, Microsoft Teams emerged as the most satisfying platform. Technical shortcomings clubbed with psychological and biological factors were found to be taking a toll on e-learning.

This innovative research is based on the perceptions of engineering students hailing majorly from Indian cities, and hence, it may be having educational stream bias and geographical bias. The research could be further extended to cover rural areas and global trends in e-learning.

The research offers a thorough analysis of e-learning platforms, as seen through the lens of engineering students. Furthermore, the analysis does not constrain itself to the technicalities and thus proves to be an all-encompassing one, potent enough to surface critical issues marring the e-learning experience.

The purpose of this paper is to design a cascaded Multilevel inverter with reduce number of switches for high power applications. This paper came up with an innovative three-phase multilevel inverter (MLI) topology, which is a cascaded structure based on classical three-legged voltage source inverter (VSI) bridges as an individual module. The prominent advantage of this topology is that it requires only one direct current (DC) link system. The main characteristic of it is that a higher number of voltage levels can be achieved with considerably a smaller number of semiconductor switches, which improves the reliability, power quality, cost and size of the system significantly.

The individual modules are cascaded through three-phase transformers to provide higher voltage at the output with the higher number of voltage levels. In this work, the phase-shifted pulse width modulation technique is implemented to verify the result.

The proposed topology is compared with three-phase cascaded H-bridge MLI (CHB-MLI) and a modified CHB-MLI topology and found better in many aspects. The proposed MLI can produce a higher number of voltage levels with fewer semiconductor switches and associated triggering circuitry. As the device count in the proposed MLI is less compared to other MLI discussed, it tends to have less switching and conduction loss which increases the efficiency and reliability. As the number of level increases, the voltage profile and the total harmonic distortion of the proposed MLI improves.

This is a transformer-based modular cascaded MLI, which is based on classical VSI bridges. Here in this topology, a single module provides all three phases. So, a single string of cascaded modules is enough for three-phase multilevel voltage generation.