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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.

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.

Enterprise systems (ES) upgrade is a complex phenomenon, yet it is possible to reduce the complexity through understanding of the upgrade drivers. The purpose of this paper is to investigate the various upgrade drivers, in order to provide a detailed understanding of the factors driving upgrade decisions.

This research is grounded in a qualitative survey design. It utilises a web-based survey questionnaire and semi-structured interviews to collect data from 41 respondents representing 23 large organisations. The data were qualitatively analysed and coded to identify the various drivers and their influence on ES upgrade decisions.

The findings suggest that the upgrade decisions are dependent on establishing the need to upgrade, which is influenced by various drivers and stakeholders interests. In addition, the findings suggest that organisations would only opt to upgrade when benefits are aligned with the upgrade and when the decision makes business sense.

In this paper, the authors propose that there is a relationship between the upgrade drivers and the upgrade strategy. However, qualitative studies can only formulate logical generalisations. Hence, future research could explore these associations through a quantitative study in order to provide probabilistic generalisation that offers either similar or conflicting arguments applicable to ES upgrade phenomenon.

This paper provides an alternative classification of upgrade drivers, and conceptualises an association between upgrade drivers and the upgrade strategy, which in turn facilitates minimising disruptions and upgrade risks.

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.

Enterprise systems (ES) upgrade is fundamental to maintaining a system’s continuous improvement and stability. However, while the extant literature is replete with research on ES upgrade decision-making, there is scant knowledge about how different decision processes facilitate this decision to upgrade. This paper aims to investigate and better understand these processes from an organisational perspective.

The study adopted a qualitative survey design, and used a Web-based questionnaire and semi-structured interviews to collect data from 23 large organisations. Data accrued were qualitatively analysed and manually coded to identify the various decision processes undertaken during ES upgrade decisions.

Analysis results reveal complex interrelations between the upgrade drivers, the need to evaluate the new version’s functionality and the upgrade impact. Understanding the interaction between these elements influences the upgrade decision process.

The study proposes ES upgrade processes that support a decision to upgrade major releases. Further research is required to offer either similar or conflicting arguments on the upgrade decision-making and provide a probabilistic generalisation of the decision-making processes.

The research offers a comprehensive and empirically supported methodical approach that embraces an evaluation of a new version’s functionality, technical requirements and concomitant upgrade implications as intrinsic decision processes. This approach assists in the decisions to establish the upgrade need and determine the level of change, effort required, impacts and associated benefits.

Enterprise systems (ES) upgrade is a complex undertaking that recurs throughout the systems’ life span, therefore, organisations need to adopt strategies and methodologies that can minimise disruptions and risks associated with upgrades. The purpose of this paper is to explore the processes undertaken during upgrading ES, to identify the upgrade project stages.

This research is grounded in a qualitative survey approach, and utilises a web-based survey questionnaire and semi-structured interviews as methods for data collection. The data were gathered from 41 respondents’ and analysed using qualitatively inductive content analysis principles to derive meaning and to identify the trends about upgrade processes.

The study findings stress the importance of adopting a methodical approach to ES upgrades. Also, it suggests that due consideration should be given to the impact of new version features and functionality, the risks and the effort required for supporting upgrade projects.

The five-stage upgrade process model can be utilised as a strategy to minimise complexity and risks associated with upgrade projects. However, this study only proposes logical generalisations; therefore, future studies could explore these stages in-depth to offer generalisable arguments applicable to ES upgrade phenomenon.

The study proposes a five-stage upgrade process model that offers a systematic approach to support upgrade projects. The proposed model extends previous models by proposing alternative strategies to support ES upgrade projects.

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.

Medical diagnosis and treatment processes exhibit a high degree of variability, as during the process execution, healthcare professionals can decide on additional steps, change the execution order or skip a task. Process models can help to document and to discuss such processes. However, depicting variability in graphical process models using standardized languages, such as Business Process Model and Notation (BPMN), can lead to large and complicated diagrams that medical staff who do not have formal training in modeling languages have difficulty understanding. This study proposes a pattern-based process visualization that medical doctors can understand without extensive training. The process descriptions using this pattern-based visualization can later be transformed into formal business process models in languages such as BPMN.

The authors derived patterns for expressing variability in healthcare processes from the literature and medical guidelines. Then, the authors evaluated and revised these patterns based on interviews with physicians in a Danish hospital.

A set of business process variability patterns was proposed to express situations with variability in hospital treatment and diagnosis processes. The interviewed medical doctors could translate the patterns into their daily work practice, and the patterns were used to model a hospital process.

When communicating with medical personnel, the patterns can be used as building blocks for documenting and discussing variable processes.

The patterns can reduce complexity in process visualization. This study provides the first validation of these patterns in a hospital.

Complex conflicts in elder abuse, its causes, typology, protection and prevention, suggest that co‐operation by multi‐disciplinary social services should be a major consideration in policy decision‐making, planned intervention and support. Casework of the Elder Mediation Project (EMP for empowerment), and related agencies, provides some practical evidence for this view. There are shared casework values and similar as well as different skills. However, when service user interests are paramount, the professional concerns of service providers for defined roles and boundaries raise ethical issues. Are there conflicts between old people's needs for trusting, confidential relationships with one worker, and case co‐ordinators' promotion of varied specialist input? Could approaching elder abuse through a multi‐skilled key worker, as well as by multi‐disciplinary social service workers, offer complementary and co‐operative interventions? Brief anonymised case notes suggest that practitioners may face professional conflicts about social intervention as casework diversifies and service user involvement in decision‐making increases, but some guidelines to good practice are offered.