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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.

The purpose of this paper is to show with figures the potentialities of knowledge‐based engineering (KBE) methods in new product development (NPD). It estimates the business value generated by a tool which integrates the handoff between engineering groups of a large aerospace company.

The paper is based on three years of observation and interviews at a leading Italian firm. A process‐based approach is used for assessing business value.

The KBE application automated the preparation of data transferred to computer‐aided engineering engineers for analysis by computer‐aided design engineers and reduced the time required by more than 90 percent. This allowed time savings which contributed to enhance product quality.

The paper is based on a single case, though its findings are consistent with prior studies. Future research will implement like applications in other contexts at the subject firm and other firms.

The paper helps managers to understand the uses and potential value of KBE applications, enhancing the awareness of NPD practitioners in a field which is still partially untapped.

The paper combines discussion of the technical aspects of implementing a KBE tool with estimates of performance improvement achieved. It can be a useful illustration of a good practice and a proof‐of‐concept for further implementations in complex engineering settings.

The purpose of this paper is to focus on developing a knowledge-based engineering (KBE) approach to recycle the knowledge accrued in an industrial organization for the mitigation of unwanted events due to human error. The recycling of the accrued knowledge is vital in mitigating the variance present at different levels of engineering applications, evaluations and assessments in assuring systems’ safety. The approach is illustrated in relation to subsea systems’ functional failure risk (FFR) analysis.

A fuzzy expert system (FES)-based approach has been proposed to facilitate FFR assessment and to make knowledge recycling possible via a rule base and membership functions (MFs). The MFs have been developed based on the experts’ knowledge, data, information, and on their insights into the selected subsea system. The rule base has been developed to fulfill requirements and guidelines specified in DNV standard DNV-RP-F116 and NORSOK standard Z-008.

It is possible to use the FES-based KBE approach to make FFR assessments of the equipment installed in a subsea system, focussing on potential functional failures and related consequences. It is possible to integrate the aforementioned approach in an engineering service provider’s existing structured information management system or in the computerized maintenance management system (CMMS) available in an asset owner’s industrial organization.

The FES-based KBE approach provides a consistent way to incorporate actual circumstances at the boundary of the input ranges or at the levels of linguistic data and risk categories. It minimizes the variations present in the assessments.

The FES-based KBE approach has been demonstrated in relation to the requirements and guidelines specified in DNV standard DNV-RP-F116 and NORSOK standard Z-008. The suggested KBE-based FES that has been utilized for FFR assessment allows the relevant quantitative and qualitative data (or information) related to equipment installed in subsea systems to be employed in a coherent manner with less variability, while improving the quality of inspection and maintenance recommendations.

The goal of this paper is to re‐evaluate the role of knowledge‐based systems (KBS) in knowledge management (KM). While knowledge‐based systems and expert systems were widely used in the past, they have now fallen from favor and are largely ignored in the knowledge management literature. This paper aims to argue that several factors have changed and it is now time to re‐evaluate the contribution that such systems can make to knowledge management.

The role of KBS in KM is explored through a comprehensive analysis of both the management and the technical literature on knowledge. The literature on KBS and expert systems is reviewed and some of the problems faced by them are highlighted. Some of the probable causes of these problems and some of the solutions that might be used to overcome them are indicated. The paper describes how knowledge systems (KS) could be used as an effective tool for managing knowledge.

The lack of success of KBS technologies for managing knowledge is mainly due to organizational and managerial issues. These problems can be solved through feasibility studies before system development activities. KS technology is now being successfully applied in a variety of newer domains that exploit its capabilities.

Some conclusions are drawn concerning integration of knowledge systems with knowledge management, problems of the early implementation of knowledge systems technology, and possible solution to overcome these problems.

The main contribution of the article is in re‐evaluating the role of knowledge‐based systems as a tool for knowledge management.

Reviews the emergence of knowledge‐based engineering tools and assesses the benefits of KBE. Describes how Jaguar Cars uses KBE to reduce vehicle development times. Discusses low‐cost KBE and its application to the small and medium‐sized company.

This paper aims to describe the development of an advisory system that helps building sound finite element (FE) models from computer-aided design data, with actual uncertainty levels expressed by error values in per cent, as today there is no widely accepted tool for FE idealisation error control.

The goal is to provide a computer-aided engineering (CAE) environment which assists the FE modelling phase. A demonstration program has been developed that leads the user through a step-by-step process and helps to detect idealisation errors. Uncertainties are identified and analysed following the procedure. An example illustrates the methodology on the collapse analysis of aerospace stiffened panels.

The design shows how a knowledge-based system can be used to aid a safe virtual product development.

The extension of current CAE environments is difficult, as the programs do not provide sufficient flexibility, changeability and FE solver independence. New developments can take the presented concept as a starting point.

The application of error control strategies increases the FE modelling fidelity and can prevent incorrect design decisions. The practical conversion of FE idealisation support depends on the ambitions of CAE software providers.

This research shows how a previously paper-and-pencil-based error control procedure can be transformed to an easy-to-use tool in modern software.

Three problematic issues followed by paradigm changes over the recent history of human intellectual endeavour are identified as 1. mysticism/superstition to – conventional science (of physics), 2. predominant use of qualitative/quantitative properties for analysis and design to – structural or systemic properties, and 3. current speculative/fragmented, multiple approaches to the “systemic view” to – a firmer knowledge-based approach reflecting the empirical and universal nature of this view. This paper aims to consider the problematic issues, to conclude that conventional science is inadequate to cope with the 2nd paradigm change and to introduce a “new science of systems” which can integrate conventional science and alleviate the 3rd problematic issue by suggesting three principles implemented by linguistic modelling as operational model.

The highly successful methodology of conventional science is followed with systemic content by suggesting three general principles of systems, namely, principle of existence (pervasiveness of structural description), principle of complexity (aggregates for emergence of outcomes) and principle of change (change by purpose or chance), and linguistic modelling of static and dynamic scenarios based on natural language as operational model. This language is processed to “elementary constituents”, of which complex structures can be constructed. These constituents are converted into reasoning schemes consisting of “ordered pairs” and “predicate logic statements” in static and dynamic states.

Stories of problematic scenarios are converted into the universal scheme of “management/producers” – “products” – “users/consumers” by constructing linguistic networks of products and semantic diagrams of organizations/user/consumers for investigating the emergence of outcomes in analysis and for designing prototypes. Problematic issues of individual objects in a scenario are resolved by methods of conventional science, which is thus integrated with systems science to form the “scientific enterprise”.

Once the new approach is debated, further developments in the mathematics of ordered pairs, predicate logic and uncertainties are needed. The linguistic basis is to be further investigated. Connection with AI and “logical atomism of Bertrand Russell” is to be explored.

Further applications to large-scale scenarios by practitioners using the “universal scheme” and development of software are needed.

The approach is rooted in accepted branches of knowledge, is highly teachable and should lead to be used by professionals and others once debated and accepted.

The engineering management of housing subsidence cases is an important field of work for many UK engineers, and remains of enduring interest to householders, insurers and other parties involved in the construction and maintenance of residential buildings. There are often difficulties in the diagnosis and repair of buildings subject to subsidence damage due to several factors, including the complex interaction between the various causative agents, the lack of a systematic investigation procedure, and the large number of available courses of remedial action. In many cases, inaccurate diagnosis of the subsidence problem has resulted in expensive remedial measures which are either unnecessary or inappropriate (and fail to arrest the movement). This paper reviews the management of subsidence cases and describes the development of a knowledge‐based system intended to improve existing procedures by ensuring greater accuracy, consistency and effectiveness of the management regime adopted by engineers. The system addresses three key aspects of the management procedure: initial diagnosis, choice of an appropriate course of investigations, and the specification of effective remedial measures. The benefits of the knowledge‐based system are contained in the concluding section of the paper.

The purpose of this article is to investigate the engineering of creative urban regions through knowledge‐based urban development. In recent years city administrators realised the importance of engineering and orchestrating knowledge city formation through visioning and planning for economic, socio‐cultural and physical development. For that purpose a new development paradigm of “knowledge‐based urban development” is formed, and quickly finds implementation ground in many parts of the globe.

The paper reviews the literature and examines global best practice experiences in order to determine how cities are engineering their creative urban regions so as to establish a base for knowledge city formation.

The paper sheds light on the different development approaches for creative urban regions, and concludes with recommendations for urban administrations planning for knowledge‐based development of creative urban regions.

The paper provides invaluable insights and discussion on the vital role of planning for knowledge‐based urban development of creative urban regions.