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This paper aims to conduct a comprehensive literature review in the tidal energy physics, the ocean environment, hydrodynamics of horizontal axis tidal turbines and bio-mimicry.

The paper provides an insight of the tidal turbine blade design and need for renewable energy sources to generate electricity through clean energy sources and less CO₂ emission. The ocean environment, along with hydrodynamic design principles of a horizontal axis tidal turbine blade, is described, including theoretical maximum efficiency, blade element momentum theory and non-dimensional forces acting on tidal turbine blades.

This review gives an overview of fish locomotion identifying the attributes of the swimming like lift-based thrust propulsion, the locomotion driving factors: dorsal fins, caudal fins in propulsion, which enable the fish to be efficient even at low tidal velocities.

Finally, after understanding the phenomenon of caudal fin propulsion and its relationship with tidal turbine blade hydrodynamics, this review focuses on the implications of bio-mimicking a curved caudal fin to design an efficient horizontal axis tidal turbine.

The purpose of this paper is to conduct a comparative analysis between a straight blade (SB) and a curved caudal-fin tidal turbine blade (CB) and to examine the aspects relating to geometry, turbulence modelling, non-dimensional forces lift and power coefficients.

The comparison utilises results obtained from a default horizontal axis tidal turbine with turbine models available from the literature. A computational design method was then developed and implemented for “horizontal axis tidal turbine blade”. Computational fluid dynamics (CFD) results for the blade design are presented in terms of lift coefficient distribution at mid-height blades, power coefficients and blade surface pressure distributions. Moving the CB back towards the SB ensures that the total blade height stays constant for all geometries. A 3D mesh independency study of a “straight blade horizontal axis tidal turbine blade” modelled using CFD was carried out. The grid convergence study was produced by employing two turbulence models, the standard k-ε model and shear stress transport (SST) in ANSYS CFX. Three parameters were investigated: mesh resolution, turbulence model, and power coefficient in the initial CFD, analysis.

It was found that the mesh resolution and the turbulence model affect the power coefficient results. The power coefficients obtained from the standard k-ε model are 15 to 20 per cent lower than the accuracy of the SST model. Further analysis was performed on both the designed blades using ANSYS CFX and SST turbulence model. The variation in pressure distributions yields to the varying lift coefficient distribution across blade spans. The lift coefficient reached its peak between 0.75 and 0.8 of the blade span where the total lift accelerates with increasing pressure before drastically dropping down at 0.9 onwards due to the escalating rotational velocity of the blades.

The work presents a computational design methodological approach that is entirely original. While this numerical method has proven to be accurate and robust for many traditional tidal turbines, it has now been verified further for CB tidal turbines.

Road passenger transportation faces a global challenge of reducing environmental pollution and greenhouse gas emissions because of the vehicle weight increases needed to enhance passenger safety and comfort. This paper aims to present a preliminary mechanical design evaluation of the Wikispeed Car (with a focus on body bending, body torsion and body crash) to assess light-weighting implications and improve the vehicle’s environmental performance without compromising safety.

For this research, finite element analysis (FEA) was performed to examine the Wikispeed chassis for light-weighting opportunities in three key aspects of the vehicle’s design, namely, for body bending the rockers (or longitudinal tubes), for body torsion (again on the rockers but also the chassis as a whole) and for crash safety – on the frontal crash structure. A two-phase approach was adopted, namely, in phase one, a 3D CAD geometry was generated and in phase, two FEA was generated. The combination of analysis results was used to develop the virtual model using FEA tools, and the model was updated based on the correlation process.

The research revealed that changing the specified material Aluminium Alloy 6061-T651 to Magnesium EN-MB10020 allows vehicle mass to be reduced by an estimated 110 kg, thus producing a concomitant 10 per cent improvement in fuel economy. The initial results imply that the current beam design made from magnesium would perform worst during a crash as the force required to buckle the beam is the lowest (between 95.2 kN and 134 kN). Steel has the largest bandwidth of force required for buckling and also requires the largest force for buckling (between 317 kN and 540 kN).

This is the first study of its kind to compare and contrast between material substitution and its impact upon Wikispeed car safety and performance.

Vehicle weight reduction represents a viable means of meeting tougher regulatory requirements designed to reduce fuel consumption and control greenhouse gas emissions. This paper aims to present an empirical and comparative analysis of lightweight magnesium materials used to replace conventional steel in passenger vehicles with internal combustion engines. The very low density of magnesium makes it a viable material for lightweighting given that it is lighter than aluminium by one-third and steel by three-fourth.

A structural evaluation case study of the “open access” Wikispeed car was undertaken. This included an assessment of material design characteristics such as bending stiffness, torsional stiffness and crashworthiness to evaluate whether magnesium provides a better alternative to the current usage of aluminium in the automotive industry.

The Wikispeed car had an issue with the rocker beam width/thickness (b/t) ratio, indicating failure in yield instead of buckling. By changing the specified material, Aluminium Alloy 6061-T651 to Magnesium EN-MB10020, it was revealed that vehicle mass could be reduced by an estimated 110 kg, in turn improving the fuel economy by 10 per cent. This, however, would require mechanical performance compromise unless the current design is modified.

This is the first time that a comparative analysis of material substitution has been made on the Wikispeed car. The results of such work will assist in the lowering of harmful greenhouse gas emissions and simultaneously augment fuel economy.

Past research has largely portrayed job choice as a relatively rational and goal‐directed behavior where applicants make decisions contingent on organizational recruitment activities, or evaluations of job and organizational attributes. Research now informs us that job choice decisions may also be based on social comparisons and social influence. The purpose of this paper is to add to this body of knowledge by examining reasons why social influence is a key factor in job choice decisions of relatively young job seekers.

The study is based on in‐depth interview data from graduating seniors at an elite business school in India.

Respondents did not see themselves as acting based on social influence as much as they perceived others around them to be. Reasons they noted for others’ socially influenced job choice decisions were: peers and seniors are seen as more accessible and trustworthy than organizations; organizations do not share all and/or objective data, driving job seekers to other sources; job seekers are clueless and hence follow a “smart” herd; and job seekers make decisions for social status signaling. Respondents pointed to socially influenced job choices as being rational behaviors under certain conditions.

Generalizability of findings may be limited to young job seekers or to the Indian context, and the authors encourage replication. The authors also acknowledge the importance of individual difference variables in job choice decisions, a factor not considered in the present research.

Given that job seekers rally around others’ notion of an attractive job or an organization, the paper outlines several implications for managerial practice.

This study, in a yet unexamined cultural context, points to the simultaneous and combined importance of normative and informational social determinants of job choice, bias blind spots in one's own job choice perceptions and decisions, gender specific socialization influences on job choices, and the notion of job fit in terms of fitment with expectations of important reference groups.

Breast cancer (BC) presents a major public health challenge world-over including India. While several risk-factors, early signs and symptoms of BC are known, the knowledge and awareness of this disease remains poor among the population. The present study aimed to determine the extent of knowledge and awareness of BC, its risk factors, early signs and symptoms and breast self-examination (BSE) practice as an early detection method among Indian college-going female students.

The authors conducted a cross-sectional survey at a University in Delhi-NCR. Data on socio-demographic, knowledge and awareness of BC including BSE was collected using a pretested questionnaire. Chi-square test and logistic regression analysis was performed. All tests were two-sided and significance was set at p < 0.05.

A total of 866 female students participated in the study with mean age of 22.32 (±0.146) years having mean body mass index (BMI) of 21.22 (±3.52). As high as 82.1% of the participants had heard of BC but while 74.8% thought early detection is possible, 70.7% believed BC cannot be prevented. Gene mutations (60.2%) were identified as a significant risk factor, while breast pain (61.4%) was commonly recognized as a sign of BC. Only 29.8% of students ever performed BSE. Increased odds of performing BSE (OR = 3.4) was found among students who recognized gene mutations as an important BC risk factor.

Knowledge and awareness of BC including BSE among female college students were found to be below average. It is suggested that there is an urgent need for increasing BC awareness among young girls through workshops and mobile-health interventions.

This study provides new information on the level of knowledge and awareness of BC risk factors, sign and symptoms and self-examination practice among young college girls. Moreover, this study advocates the need for design and implementation of a sustainable digital health model for active population BC screening, which is not being done currently.

BC is a highly aggressive disease, which is now one of the leading causes of morbidity and mortality in India and world over. Although the knowledge of BC risk factors and its signs and symptoms have increased, the awareness of these elements among the general population at large is low and/or missing, especially in India. Furthermore, as a consequence of unorganized screening programs in the country, majority of women are presenting young with locally advanced disease. Understanding the existing level of knowledge and educating school, college and University students of the pertinent factors and screening practices such as BSE could drastically help in improving the self-screening and/or clinical examination rates. This could potentially lead to early detection and improved prognosis, thus ameliorating disease burden.

This study is one of the few studies conducted in India among young female college students belonging to non-medical backgrounds, delineating the level of knowledge and awareness of BC risk factors and signs and symptoms along with practice of early detection method such as BSE. The study has a considerable sample size and provides valuable evidence for a need to implement programs incorporating digital health models for accelerating awareness and screening of young girls in both rural and urban settings.