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This study aims to assess the vibrational behavior of a large transport airship based on finite element (FE) simulation and modal testing of its scaled model.

A full-size parametric FE model of the airframe was established according to the structural layout of the composite beam-cable airframe of the airship, and vibrational analysis of the airframe was conducted. The influence of cable pre-tension load on the inherent properties of the airframe was investigated. Based on the simplification of the full-size FE model, scaled numerical and test models of the airframe, with a geometric scale factor of 1:50, were established and built.

The simulation and test results of the scaled models indicated that the mode shapes of the full-size and scaled models were similar. The natural frequencies of both the full-size and scaled models complied with the theoretical similarity relation of the frequency response.

This study demonstrated that the vibrational test results of the scaled model with very large scaling can be used to characterize the modal properties of the beam-cable airframe of a large transport airship.

The purpose of this study is to investigate a new and innovative sandwich material evaluating its capability for use in space habitat structural components in deployable and foldable configurations. The main habitat requirements were considered in the preliminary design of a typical space outpost, proposing a preliminary architecture.

The stiffness properties of the innovative sandwich (MAdFlex ®) were evaluated using numerical and experimental investigations. Four-point bending tests were performed for complete sandwich characterization. Numerical FE simulations were performed using typical material properties and performance. The application to a space habitat main structure as a basic material has also been discussed and presented.

MAdFlex basic stiffness performances have been determined considering its double behavior: sufficiently stiff if loaded in a specific direction, flexible if loaded in the opposite direction and enhanced folding performance. Successful application to a typical space habitat confirms the validity and convenience of such a material in designing alternative structures.

The innovative material demonstrates wide potential for structural application and design in demanding space situations under operating conditions and in stored ones at launch.

Several simple deployable structural components can be designed and optimized both for the space environment and for the more traditional terrestrial applications.

Simplification in structural design can be derived from deployable low-weight items.

Innovative customized material in sandwich configuration has been proposed and investigated with the aim to demonstrate its potentiality and validity in alternative design architecture.

Abnormal vibrations often occur in the liquid oxygen kerosene transmission pipelines of rocket engines, which seriously threaten their safety. Improper handling can result in failed rocket launches and significant economic losses. Therefore, this paper aims to examine vibrations in transmission pipelines.

In this study, a three-dimensional high-pressure pipeline model composed of corrugated pipes, multi-section bent pipes, and other auxiliary structures was established. The fluid–solid coupling method was used to analyse vibration characteristics of the pipeline under various external excitations. The simulation results were visualised using MATLAB, and their validity was verified via a thermal test.

In this study, the vibration mechanism of a complex high-pressure pipeline was examined via a visualisation method. The results showed that the low-frequency vibration of the pipe was caused by fluid self-excited pressure pulsation, whereas the vibration of the engine system caused a high-frequency vibration of the pipeline. The excitation of external pressure pulses did not significantly affect the vibrations of the pipelines. The visualisation results indicated that the severe vibration position of the pipeline thermal test is mainly concentrated between the inlet and outlet and between the two bellows.

The results of this study aid in understanding the causes of abnormal vibrations in rocket engine pipelines.

The causes of different vibration frequencies in the complex pipelines of rocket engines and the propagation characteristics of external vibration excitation were obtained.

As the excessive lifting force can lead to catwalk rollover and well site accidents, the lifting process boundary conditions and structural parameters have a significant effect lifting force, it is important to analysis the structural parameters on the maximum lifting force in the lifting process of power catwalk.

A new model is proposed to analyze the influence of structure parameters on its lifting force for lifting power catwalk in this paper, and the geometric and dynamic equations are established according to the different boundary conditions in different stages. In addition, the establishment of dynamics equations is based on D'Alembert's principle. To solve the model, dynamic analysis software is developed, which uses c # call MATLAB to solve the geometric and dynamic equations. The maximum lifting force is analyzed and optimized according to the software, the influence of structural parameters on the maximum lifting force is obtained and the correctness of the optimization is proved by experiments.

The best value of offset e is 0. The length of L22 should as small as possible while the installation size of the end of the conveying arm are guaranteed. The length of L1 should as small as possible while ensuring the not exceed the maximum value. The maximum lifting force remain the same in the second phase, the maximum lifting force decreases with the increase of Lcp, Lcpshould as small as possible. The maximum pressure of the hydraulic oil dropped by an average of 13.62% under optimized parameters.

This paper provides a theoretical basis for the selection of hydraulic winch, which also provides the theoretical basis and data support for the design and optimization of the structural parameters of the power catwalk.

This research has industrial applications in SJ Petroleum Machinery CO.LTD, SINOPEC (China) .CANRIG, North Rig, TESCO, Sichuan HONGHUA petroleum equipment CO.LTD of CNPC., Baoji Oil field Machinery CO.LTD, SJ Petroleum Machinery Co. LTD of SINOPEC, Yantai Jereh Oilfield Services Group CO.LTD, Nanyang clips oil equipment (group) CO. LTD, etc are the likely users.

A new model is proposed to analyze the lifting force of lifting power catwalk. The model takes into account the inertia force of the structure, development of dynamics software and analysis and optimization of structural parameters. The maximum lifting force is analyzed and optimized according to the software, the influence of structural parameters on the maximum lifting force is obtained and the correctness of the optimization is proved by experiments.

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.

Logistics and supply chain management has been elevated to a strategic level whereby firms can simultaneously achieve differentiation and low cost for sustained competitive advantage. Empirical studies have often concentrated on logistics management in developed Western countries, displaying a bias towards the USA. This study applies the competency approach to explore logistics in Taiwan. A survey of 1,200 manufacturing firms was undertaken in order to examine the relationships between logistics competency, logistics performance, and financial performance, using exploratory factor analysis and the structural equation modelling technique. Four logistics competencies, namely, integration and knowledge competency, customer focused logistics competency, measurement competency, and agility competency were identified. The research findings revealed that (1) logistics competency was significantly related to logistics performance but not significantly associated with financial performance, and (2) logistics performance was positively associated with financial performance. These findings also implied that logistics competency has an indirect effect on financial performance through logistics performance. This finding confirmed the “world-class” logistics competencies (i.e. positioning, integration, agility, and measurement) as identified by MSUGLRT (1995). In addition, it suggests that logistics competency in a huge geographic area such as America can have the same effect in a smaller geographic area such as Taiwan.

This paper aims to demonstrate the design and verification of a 3D reticulate octahedral cellular structure using both analytical modeling and additive manufacturing. Traditionally, it has been difficult to develop and verify designs for 3D cellular structures due to their design complexity.

Unit cell modeling approach was used to model the octahedral cellular structure. By applying structural symmetry simplification, the cellular structure was simplified into a representative geometry that could be further designed with a standard beam theory. The verification samples were fabricated with EBM process using Ti6Al4V as materials, and compressive testing were performed to evaluate their properties. In addition, designs with different number of unit cells were investigated to evaluate their size effect.

Explicit mechanical property design (including modulus and compressive strength) of the octahedral cellular structure was realized via parametric equations driven by geometrical designs and material types. In addition, it was verified both numerically and experimentally that the octahedral cellular structure exhibit unusual size effect, which is highly predictable. Unlike some of the other cellular structures, the octahedral cellular structure exhibits softening behavior when the number of unit cell increases between the sandwich skins, which could be explained by the upsetting effect commonly observed in bulk deformation processes.

This paper established a more comprehensive understanding in the design of octahedral cellular structures, which could enable this type of structure to be designed for sandwich structures with higher fidelity. Therefore, this study not only demonstrated an efficient methodology to design 3D cellular structures using additive manufacturing, but also facilitated the development of design for an additive manufacturing theory.

Many development interventions fail to report results that are important to local people (intended beneficiaries of the intervention) but not of strategic importance to the donors funding the work. Failure to report unexpected results, or those not linked to strategic goals, contributes to an overly negative view from external evaluations by donors and agencies. The causes of the mismatch between actual and demonstrated results failure were studied through stakeholder interests. The paper aims to discuss these issues.

Nine project and programme managers of similar but unrelated projects were interviewed. From the interviews, previous studies and project publications, the challenges posed by differing interests and different perceptions in reporting stakeholder activities, outputs and outcomes, were identified. The complex environment of many development interventions was analysed and the work was contextualised with a peacebuilding project in Sri Lanka, which the author has previously studied. A stakeholder role and perception analysis was used to map the challenges at four times in the project cycle, producing a dynamic stakeholder analysis.

The failure to fully report intervention results was linked to the changing role of competing stakeholder interests as a project proceeds, the conflicting perceptions of stakeholders, the structural over-simplification of a complex environment and power differentials that allow donors to misappropriate the role of clients.

Current practice in designing and evaluating projects needs to improve reporting of beneficiary interests.

To the author’s knowledge there are no prior publications in this area of research (under-reporting of development intervention results); the paper is considered highly original.

Seismic isolation, as an effective risk mitigation strategy of building/bridge structures, is incorporated into AP1000 nuclear power plants (NPPs) to alleviate the seismic damage that may occur to traditional structures of NPPs during their service. This is to promote the passive safety concept in the structural design of AP1000 NPPs against earthquakes.

In conjunction with seismic isolation, tuned-mass-damping (TMD) is integrated into the seismic resistance system of AP1000 NPPs to satisfy the multi-functional purposes. The proposed base-isolation-tuned-mass-damper (BIS-TMD) is studied by comparing the seismic performance of NPPs with four different design configurations (i.e. without BIS, BIS, BIS-TMD and TMD) with the design parameters of the TMD subsystem optimized.

Such a new seismic protection system (BIS-TMD) is proved to be promising because the advantages of BIS and TMD can be fully used. The benefits of the new structure include effective energy dissipation (i.e. wide vibration absorption band and a stable damping effect), which results in the high performance of NPPs subject to earthquakes with various intensity levels and spectra features.

Parametric studies are performed to demonstrate the seismic robustness (e.g. consistent performance against the changing mass of the water in the gravity liquid tank and mechanical properties) which further ensures that seismic safety requirements of NPPs can be satisfied through the use of BIS-TMD.

This empirical study examines the psychometric comparability of Aaker's Brand Personality Scale (Aaker, 1997) in sponsorship matching. It employs a structural validation protocol - the congenerity test (Ohanion, 1990) - to investigate the extent to which sports events and sponsors can be psychometrically matched. The results show that sports events and sponsors are comparable only in terms of limited numbers of the dimensions of the a priori scale. Theoretical and practical implications are discussed.