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To provide valuable information for scholars to grasp the current situations, hotspots and future development trends of reliability analysis area.

In this paper, recent researches on efficient reliability analysis and applications in complex engineering structures like aeroengine rotor systems are reviewd.

The recent reliability analysis advances of engineering application in aeroengine rotor system are highlighted, it is worth pointing out that the surrogate model methods hold great efficiency and accuracy advantages in the complex reliability analysis of aeroengine rotor system, since its strong computing power can effectively reduce the analysis time consumption and accelerate the development procedures of aeroengine. Moreover, considering the multi-objective, multi-disciplinary, high-dimensionality and time-varying problems are the common problems in various complex engineering fields, the surrogate model methods and its developed methods also have broad application prospects in the future.

For the strong demand for efficient reliability design technique, this review paper may help to highlights the benefits of reliability analysis methods not only in academia but also in practical engineering application like aeroengine rotor system.

This paper aims to investigate the electrochromic (EC) properties of poly(triphenylamine alkyl ether) and poly(triphenylamine aryl ether) in two different electrolyte solution to study the resistive switching behaviour of acid-doped poly(triphenylamine alkyl ether).

By Buchwald–Hartwig coupling reaction, two novel poly[N-p-phenoxy-N-[4-[2-(2-methoxyethoxy)ethoxy]ethoxy]triphenylamineandpoly[N,N-bis(4-phenoxy)]triphenylamine were synthesized from 4-phenoxyaniline and two dibromo aromatic compounds, 1,2-bis[β,β′-(p-bromophenoxy)ethoxy]ethane and bis(4-bromophenyl) ether.

Poly(triphenylamine alkyl ether) displayed excellent EC characteristics, with a coloration change from a colourless neutral state to light blue and red oxidized states, while poly(triphenylamine aryl ether) showed coloration a change from a colourless neutral state to light blue oxidized state in tetrabutylammonium perchlorate electrolyte solution. Moreover, p-toluenesulfonic acid-doped poly(triphenylamine alkyl ether) exhibited a non-volatile bistable resistive switching behaviour with a high high-conductivity/low-conductivity ratio of up to 104, long retention time exceeding 2.5 × 10³ s and the switching threshold voltage was also lower than −2V.

In this paper, the non-volatile bistable resistive switching behaviour of acid-dopedpoly(triphenylamine alkyl ether) was in accordance with the molar ratio of 1:1. The effects of different molar ratios remained to be studied.

Poly(triphenylamine ether)s may find optoelectronic applications as new EC and resistive switching materials.

The effects of alkyl and aryl ether structures in the main chain on the EC and resistive switching behaviour of triphenylamine unit have not yet been reported.

Aligned with cultural attraction theory, this study aims to propose a cultural attractiveness index (CAI) that helps tourism practitioners and scholars evaluate and track the cultural attractiveness of urban destinations (cities) in the context of sustainable development.

Applying the Delphi method, a panel of experts was recruited to conduct three rounds of review to generate dimensions and determine indicators and corresponding weights. This study then verified CAI with statistical data from three sample cities (London, New York and Beijing).

A 12-item three-dimensional index structure (cultural places, cultural activities and cultural atmosphere) was created as CAI. This study also applied the CAI to compare three sample cities. The comparison identified possible aspects to be improved in developing cultural attractiveness, confirming CAI’s usefulness in fostering sustainable development.

The new CAI offers an effective tool for ascertaining a sustainable city’s cultural attractiveness while extending the cultural attraction theory and filling the existing gaps in the literature through a benchmark instrument. The CAI also provides an effective tool for destination managers and tourism practitioners for their sustainable initiatives in cities.

本研究旨在于建立文化吸引力指数(CAI), 帮助旅游从业者和学者在可持续发展的背景下评估和跟踪旅游城市的文化吸引力。

本研究采用德尔菲专家咨询法, 聘请了一个专家小组对指标体系进行了三轮审查, 以建立评价维度、确定指标和相应的权重。最后, 该研究用三个样本城市(伦敦、纽约和北京)的统计数据验证了CAI。

本文创建了一个由3个维度12项指标组成的评价指数体系CAI（文化场所, 文化活动和文化氛围）。三个样本城市的相关统计数据也验证了CAI评价体系在促进城市可持续发展方面的科学性, 也通过跨城市比较找到各自可进一步提升文化吸引力的维度。

新的CAI为衡量可持续城市的文化吸引力提供了评价体系, 填补了现有文献的空白。该CAI还为目的地管理者和旅游从业者提供了一个有效的基准工具, 以促进可持续城市发展目标的实现。

alineado con la teoría de la atracción cultural, el estudio propone un índice de atractivo cultural (CAI) que ayuda a los profesionales y académicos del turismo a evaluar y rastrear el atractivo cultural de los destinos urbanos (ciudades) en el contexto del desarrollo sostenible.

Aplicando el método Delphi, se reclutó un panel de expertos para realizar tres rondas de revisión para generar dimensiones y determinar indicadores y pesos correspondientes. Luego, el estudio verificó el CAI con datos estadísticos de tres ciudades de muestra (Londres, Nueva York y Beijing).

Se creó como CAI una estructura de índice tridimensional de 12 ítems (lugares culturales, actividades culturales y atmósfera cultural). El estudio también aplicó el CAI para comparar tres ciudades de muestra. La comparación identificó posibles aspectos a mejorar en el desarrollo del atractivo cultural, lo que confirma la utilidad de CAI para fomentar el desarrollo sostenible en las ciudades de la muestra.

El nuevo CAI ofrece una herramienta eficaz para determinar el atractivo cultural de una ciudad sostenible al mismo tiempo que llena los vacíos existentes en la literatura a través de un instrumento de referencia. El CAI también proporciona una herramienta eficaz para los administradores de destinos y profesionales del turismo para sus iniciativas sostenibles en las ciudades.

Both geometric and non-geometric parameters have noticeable influence on the absolute positional accuracy of 6-dof articulated industrial robot. This paper aims to enhance it and improve the applicability in the field of flexible assembling processing and parts fabrication by developing a more practical parameter identification model.

The model is developed by considering both geometric parameters and joint stiffness; geometric parameters contain 27 parameters and the parallelism problem between axes 2 and 3 is involved by introducing a new parameter. The joint stiffness, as the non-geometric parameter considered in this paper, is considered by regarding the industrial robot as a rigid linkage and flexible joint model and adds six parameters. The model is formulated as the form of error via linearization.

The performance of the proposed model is validated by an experiment which is developed on KUKA KR500-3 robot. An experiment is implemented by measuring 20 positions in the work space of this robot, obtaining least-square solution of measured positions by the software MATLAB and comparing the result with the solution without considering joint stiffness. It illustrates that the identification model considering both joint stiffness and geometric parameters can modify the theoretical position of robots more accurately, where the error is within 0.5 mm in this case, and the volatility is also reduced.

A new parameter identification model is proposed and verified. According to the experimental result, the absolute positional accuracy can be remarkably enhanced and the stability of the results can be improved, which provide more accurate parameter identification for calibration and further application.

The purpose of this study was to investigate the microstructural evolution and hydrolytic stability of poly(phenylborosiloxane) (PPhBS) to further use and develop the oligomers as heat-resistant modifiers.

PPhBS was synthesized by direct co-condensation of boric acid (BA) and phenyltriethoxysilane (PTEOS). The structural evolution of PPhBS at high temperature was investigated by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), differential thermal analysis (DTA), in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and 29Si nuclear magnetic resonance (NMR) spectroscopy. In addition, the change in the morphology of the PPhBS powder was examined to demonstrate the evolution of the chemical bonds, and the hydrolytic stability of PPhBS was investigated by a combination of X-ray diffraction (XRD) analysis, measurement of the mass loss in water and FTIR spectroscopy.

The results revealed that a cross-linking network was gradually formed with increasing temperature through the condensation of the residual hydroxyl groups in PPhBS, and the Si-OH and B-OH bonds remained even at a high temperature of 450°C. Furthermore, heat treatment improved the hydrolytic stability of the oligomer. The hydrolysis of the B-O-B bonds in PPhBS was reversible, whereas the Si-O-Si and Si-O-B bonds were highly resistant to hydrolysis.

The prepared PPhBS can be used as a heat-resistant modifier in adhesives, sealants, coatings and composite matrices.

Investigation of the structural evolution of a polyborosiloxane at high temperature by DRIFTS is a novel approach that avoided interference from moisture in the air. The insoluble mass fraction and the FTIR spectrum of PPhBS washed with water were used to investigate the hydrolytic stability of PPhBS.

To develop a method based on urea/microwave treatment for improving the dyeability of the flax fibre.

The treatment was carried out under a variety of conditions in terms of the power of the microwave, the time of microwave treatment and the use of urea in the treatment solution. The physical chemical properties of the treated flax fibres were characterised using a variety of techniques including scanning electron microscopy (SEM), X‐ray diffractometry, spectrophotometric measurement and tensile measurement.

It was found that the treated flax fibres had significantly improved dyeability. The causes to the improvement of the dyeability of the flax fibre were found to be the increased absorption of dye on the fibre and the increased reaction probability between the dye and the fibre. The procedure for optimum modification appeared to be soaking the flax fabrics in 10 per cent urea solution; treating the fabrics with microwave at 350 W for 2.5 minutes; and treating the fabrics with microwave at 700 W for one minute.

The treatment method developed addressed a problem of great concern in textile coloration, i.e. poor dyeability of flax fibre. The method developed provided a practical and effective solution to such a problem.

The method of treatment of flax fibre, involving soaking in urea and baking in microwave, for the improvement of dyeability was novel. The method could be adapted for use in industrial scale flax dyeing with satisfactory levels of exhaustion and fixation.

A new wire arc additive manufacturing (WAAM) process combined with gravity-driven powder feeding was developed to fabricate components of tungsten carbide (WC)-reinforced iron matrix composites. The purpose of this study was to investigate the particle transportation mechanism during deposition and determine the effects of WC particle size on the microstructure and properties of the so-fabricated component.

Thin-walled samples were deposited by the new WAAM using two WC particles of different sizes. A series of in-depth investigations were conducted to reveal the differences in the macro morphology, microstructure, tensile performance and wear properties.

The results showed that inward convection and gravity were the main factors affecting WC transportation in the molten pool. Large WC particles have higher ability than small particles to penetrate into the molten pool and survive severe dissolution. Small WC particles were more likely to be completely dissolved around the top surface, forming a thicker region of reticulate (Fe, W)₆C. Large WC particles can slow down the inward convection more, thereby leading to an increase in width and a decrease in the layer height of the weld bead. The mechanical properties and wear resistance significantly increased owing to reinforcement. Comparatively, samples with large WC particles showed inferior tensile properties owing to their higher susceptibility to cracks.

Fabricating metal matrix composites through the WAAM process is a novel concept that still requires further investigation. Apart from the self-designed gravity-driven powder feeding, the unique aspects of this study also include the revelation of the particle transportation mechanism of WC particles during deposition.

To evaluate the photoelectrochemical characteristics of polymer doped with CdSe and CdSe/TiO₂ for improved photoelectric conversion efficiency.

A method was set‐up to dope the nano‐CdSe with poly‐perylene‐tetracarboxylic imide (PPI) in the nano‐TiO₂/ITO films, which were characterised by X‐ray diffraction; electrochemical analytical system; multifunctional grating spectrometer; digital photometer and ultrasonic cleanout instrument, etc.

The modification of PPI doped with CdSe and CdSe/TiO₂ showed significant elevation of the monochromatic incident photo‐to‐electron conversion efficiency (IPCE) of the photoelectrode, which was about 3 per cent. The doping caused a tone up separate efficiency of charge, restraining the complex of electron‐cavity by doped nano‐CdSe. Therefore, the photocurrent of the TiO₂ film doped with nano‐CdSe was about three times higher than that without.

The mixed film could also be formed from conjugated polymer mixed with polymer and inorganic particle, based on polymer doped with CdSe and CdSe/TiO₂. In addition, the monochromatic incident IPCE of the photoelectrode needs to be extensively studied.

The treatment method developed provided a practical and effective solution to increasing the ICPE.

The method for doping polymer with CdSe and CdSe/TiO₂ was novel and could probably be adapted for the manufacture of solar cell.

The purpose of this paper is to prepare polypyrrolone nanofibres and investigate the effects of concentration of polypyrrolone precursor and voltage on polypyrrolone precursor nanofibres by electrospinning, in order to achieve ideal nanofibres.

Polypyrrolone nanofibres were prepared by polypyrrolone precursor electrospinning. Various fibres were made with different concentrations of polypyrrolone precursor and different voltages. Morphology of fibres was characterised by scanning electron microscopy to study the effect of different preparation conditions on morphology of fibres.

A method of preparation of polypyrrolone nanofibres with the polypyrrolone precursor by electrospinning was introduced which had not been reported. The effects of concentration of polypyrrolone precursor and voltage on the morphology of the nanofibres were studied. It was found that the concentration of polypyrrolone precursor was the major factor and the voltage also affected the distribution and dimension of polypyrrolone fibres to an extent.

Polypyrrolone nanofibres provided potential applications in solar cells and field‐effect transistors.

To the best of the authors' knowledge, there is no literature on the preparation of polypyrrolone nanofibres by electrospinning. Herein the preparation of polypyrrolone nanofibres by electrospinning is first reported. The polypyrrolone nanofibres might be used in solar cell, non‐linear optics, conducting and semi‐conducting materials.

The purpose of this paper is to improve opening performance of bi-directional rotation gas face seals by investigating the hydrodynamic effect of non-closed elliptical grooves.

A model of non-closed elliptical groove bi-directional rotation gas face seal is developed. The distribution of lubricating film pressure is obtained by solving gas Reynolds equations with the finite difference method. The program iterates repeatedly until the convergence criterion on the opening force is satisfied, and the sealing performance is finally obtained.

Non-closed elliptical groove presents much stronger hydrodynamic effect than the closed groove because of drop of the gas resistance flowing into grooves. Besides, the non-closed elliptical groove presents significant hydrodynamic effect under bi-directional rotation conditions, and an increase of over 40 per cent is obtained for the opening force at seal pressure 4.5 MPa, as same level as the unidirectional spiral groove gas seal. In the case of bi-directional rotation, the value of the inclination angle is recommended to set as 90° presenting a structure symmetry so as to keep best opening performance for both positive and reverse rotation.

A model of non-closed elliptical groove bi-directional rotation gas face seal is established. The hydrodynamic mechanism of this gas seal is illustrated. Parametric investigation of inclination angle and integrity rate is presented for the non-closed elliptical groove bi-directional rotation gas face seal.