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The purpose of this paper is to investigate the buckling strength of simply supported plates with mechanical extension-twisting coupling. Bounds of the compression buckling strength are presented for a special sub-class of extension-twisting coupled laminate that is free from the thermal distortions that generally arise in this class of coupled laminate as a result of the high temperature curing process. These special laminates are generally referred to as hygro-thermally curvature-stable (HTCS).

This paper gives an overview of the methodology for developing laminates with extension-twisting coupling properties, which are derived from a parent laminate with HTCS properties. A closed form buckling solution is applicable for this special class of coupled laminate, which facilitates an assessment of compression buckling strength performance for the entire laminate design space.

Extension-twisting coupled laminates have potential applications in the design of aero-elastic compliant rotor blades, where the speed of the rotating blade, and the resulting centrifugal force, can be used to control blade twist. Extension-twisting coupling reduces the compression buckling performance of the blade, which represents an important static design constraint. However, the performance has been shown to be higher than competing designs with extension-shearing coupling in many cases.

Bounds of the buckling curves have been presented for the entire HTCS laminate design space, possessing extension-twisting and shearing-bending coupling, in which the laminates contain standard ply angle orientations and up to 21 plies. These laminates can be manufactured without the undesirable thermal warping distortions that generally affect this class of coupled laminate, and in particular, those containing angle plies only; previously thought to be the only form of laminate design from which this particular type of mechanical coupling can be derived.

Agricultural extension has played a central role in building the capacity of smallholders for decades. In efforts to improve extension outcomes, demand-driven approaches have emerged to better align extension content with smallholder context. The aim of this paper is to explore the challenges facing demand-driven extension in Papua New Guinea.

Exploratory case study methodology was used to explore the challenges facing demand-driven extension from the perspectives of 11 practitioners experienced in community engagement in Papua New Guinea.

Although there is great potential for demand-driven extension, this research found extension services in Papua New Guinea are ill-equipped to introduce and sustain a resource-intensive approach like demand-driven extension. It further found that rural farmers who extension organisations have long neglected lack the necessary skills and trust to gain from these services.

A limitation of this research is that it only reflects the opinions of practitioners working in Papua New Guinea. Further research featuring a broader sample of value chain actors connected to extension would provide a more complete understanding of the potential challenges to demand-driven engagement in this context.

With a growing interest among development projects to utilise demand-driven engagement with farmers, this research is the first study to explore the challenge facing this promising approach in Papua New Guinea.

The purpose of this paper is to study the new (3 + 1)-dimensional integrable fourth-order nonlinear equation which is used to model the shallow water waves.

By means of the Cole–Hopf transform, the bilinear form of the studied equation is extracted. Then the ansatz function method combined with the symbolic computation is implemented to construct the breather, multiwave and the interaction wave solutions. In addition, the subequation method tis also used to search for the diverse travelling wave solutions.

The breather, multiwave and the interaction wave solutions and other wave solutions like the singular periodic wave structure and dark wave structure are obtained. To the author’s knowledge, the solutions obtained are all new and have never been reported before.

The solutions obtained in this work have never appeared in other literature and can be regarded as an extension of the solutions for the new (3 + 1)-dimensional integrable fourth-order nonlinear equation.

The purpose of this paper is to propose Extensible Markup Language (XML) data partitioning schemes that can cope with static and dynamic allocation for parallel holistic twig joins: grid metadata model for XML (GMX) and streams‐based partitioning method for XML (SPX).

GMX exploits the relationships between XML documents and query patterns to perform workload‐aware partitioning of XML data. Specifically, the paper constructs a two‐dimensional model with a document dimension and a query dimension in which each object in a dimension is composed from XML metadata related to the dimension. GMX provides a set of XML data partitioning methods that include document clustering, query clustering, document‐based refinement, query‐based refinement, and query‐path refinement, thereby enabling XML data partitioning based on the static information of XML metadata. In contrast, SPX explores the structural relationships of query elements and a range‐containment property of XML streams to generate partitions and allocate them to cluster nodes on‐the‐fly.

GMX provides several salient features: a set of partition granularities that balance workloads of query processing costs among cluster nodes statically; inter‐query parallelism as well as intra‐query parallelism at multiple extents; and better parallel query performance when all estimated queries are executed simultaneously to meet their probability of query occurrences in the system. SPX also offers the following features: minimal computation time to generate partitions; balancing skewed workloads dynamically on the system; producing higher intra‐query parallelism; and gaining better parallel query performance.

The current status of the proposed XML data partitioning schemes does not take into account XML data updates, e.g. new XML documents and query pattern changes submitted by users on the system.

Note that effectiveness of the XML data partitioning schemes mainly relies on the accuracy of the cost model to estimate query processing costs. The cost model must be adjusted to reflect characteristics of a system platform used in the implementation.

This paper proposes novel schemes of conducting XML data partitioning to achieve both static and dynamic workload balance.

The purpose of this paper is to understand how digital technologies can help healthcare organisations and improve the exploration-exploitation paradox over time. The authors explore inputs, processes and outcomes of implementing digital transformation programs and advance four testable propositions.

The authors conducted multiple case studies with embedded units of analysis: digital transformation processes; hospitals; and regional healthcare systems. Primary sources come from 107 semi-structured interviews with key informants within 14 Italian hospitals between 2009 through 2011.

Three complementary paths emerge as fundamental to balance exploratory and exploitatory efforts in healthcare: assets digitalisation within hospitals; digitally based process integration; and disruptive decision-making through analytics. Intra- and inter-path characteristics are discussed to show how digital transformation can both move hospital within the exploration-exploitation space.

By its very nature, this study is exploratory. Notwithstanding the number of cases and interviews, its generalisability is limited.

Digital transformation programs are fundamental to resolve the tensions raised by the exploration-exploitation paradox. Their implementation leads to better performance (cost reductions, quality improvements). A framework is provided for practitioners to make better decisions.

This study sheds new light on how digital technologies are actually adopted and adapted in healthcare contexts. It does it by entailing a longitudinal perspective.

A substantial number of production assets in the offshore oil and gas industry are facing operation beyond their anticipated design life, thus necessitating a service life extension program in the future. Selection of the most suitable strategy among a wide range of potential options to extend the lifetime of equipment (e.g. re-using, reconditioning, remanufacturing, refurbishing and adding on safety/process control measures) remains a challenging task that involves several technical, economic and organizational complexities. In order to tackle this challenge, it is crucial to develop analytical tools and methods capable of evaluating and prioritizing end-of-life strategies with respect to their associated costs and quantifiable benefits. The paper aims to discuss these issues.

This paper presents a life-cycle cost-benefit analysis approach to identify the most suitable life extension strategy for ageing offshore assets by taking into account all the capital, installation, operational, maintenance and risk expenditures during the extended phase of operation. The potential of the proposed methodology is demonstrated through a case study involving a three-phase separator vessel which was constructed in the mid-1970s.

The results from the application case indicate that the capital expenditure (CapEx) accounts for the largest portion of life cycle cost for the replacement strategy, while risk expenditure (RiskEx) is the major contributor to costs associated with life extension. A sensitivity analysis is also conducted to identify factors having the greatest impact on the optimum life extension solution, including oil price, production rate and money interest rate.

In the past, the decisions about life extension or replacement of in-service equipment were often made in a qualitative way based on experience and judgment of engineers and inspectors. This study presents a “quantitative” framework to evaluate and compare the costs, benefits and risks associated with life extension strategies and subsequently to select the best strategy based on benefit/cost ratios.

To the best of authors’ knowledge, no studies before have applied life cycle assessment and cost-benefit analysis methods to prioritize the potential life extension strategies in the oil and gas industry sector. The proposed approach not only assists decision makers in selecting the most suitable life extension strategy but also helps duty holders reduce the costs corresponding to life extension execution.

Abuse and reuse of syringes will let nursing professionals suffer serious risk of cross-infection of diseases. The purpose of this paper is to propose a flexible and extensible innovative design approach of single-use safety syringe. Besides, the evaluation procedure for syringe has also been developed.

By using the innovative design processes, based on the Su-Field model and extension method, this study presents designing of a new single-use safety syringe incorporating features and discarding problems.

The solution of design problem indicated that the substance “fingers grip cap” should be replaced. The advantages and disadvantages of proposed new designs of safety syringe as well as the perceived differences on the use of the safety syringes can be found out by using Focus Group Interview method.

This research focussed on the function innovation without considering the psychology effect, such as shape aesthetics and users’ emotion.

The single-use safety syringe design and corresponding examples are adopted to explain the design processes and confirm the feasibility of the proposed approach.

This paper proposes a flexible and extensible innovative design approach of single-use safety syringe which is seldom studied. Importance and emergency of safety syringe design cannot be overemphasized.

Partially‐decoupled upwind‐based total‐variation‐diminishing (TVD) finite‐difference schemes for the solution of the conservation laws governing two‐dimensional non‐equilibrium vibrationally relaxing and chemically reacting flows of thermally‐perfect gaseous mixtures are presented. In these methods, a novel partially‐decoupled flux‐difference splitting approach is adopted. The fluid conservation laws and species concentration and vibrational energy equations are decoupled by means of a frozen flow approximation. The resulting partially‐decoupled gas‐dynamic and thermodynamic subsystems are then solved alternately in a lagged manner within a time marching procedure, thereby providing explicit coupling between the two equation sets. Both time‐split semi‐implicit and factored implicit flux‐limited TVD upwind schemes are described. The semi‐implicit formulation is more appropriate for unsteady applications whereas the factored implicit form is useful for obtaining steady‐state solutions. Extensions of Roe's approximate Riemann solvers, giving the eigenvalues and eigenvectors of the fully coupled systems, are used to evaluate the numerical flux functions. Additional modifications to the Riemann solutions are also described which ensure that the approximate solutions are not aphysical. The proposed partially‐decoupled methods are shown to have several computational advantages over chemistry‐split and fully coupled techniques. Furthermore, numerical results for single, complex, and double Mach reflection flows, as well as corner‐expansion and blunt‐body flows, using a five‐species four‐temperature model for air demonstrate the capabilities of the methods.

The purpose of this paper is to demonstrate new design concepts for 24 classes of laminate, which have been derived as part of an ongoing study on the development of a unified approach to the characterization of coupled laminates. The paper presents a description of each class of coupled laminate.

The paper gives an overview of the desired performance and requirements of a smart leading edge device, its aerodynamic design for the wind tunnel tests and the structural pre‐design and sizing of the full‐scale leading edge section which will be tested in the wind tunnel.

Coupled laminates have potential applications in the design of aero‐elastic compliant rotor blades or aircraft wing structures, by introducing tailored extension‐twist and/or shear‐extension coupling at the laminate level; or in the design of thermally activated morphing structures, by exploiting more complex coupling behaviour.

These laminates contain standard cross‐ply and/or angle‐ply combinations, although double angle‐ply laminates are also considered, and correspond to any standard fibre/matrix system with a constant ply thickness throughout.

The vast majority of the laminate described possess coupling behaviour not previously identified in the literature.