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This paper aims to develop a theoretical method to analyze the rotation accuracy of rotating machinery with multi-support structures. The method effectively considers the geometric errors and assembly deformation of parts.

A method composed of matrix and FEA methods is proposed to do the analysis. The deviation propagation analysis results and external loads are set as boundary conditions of the model which is built with Timoshenko beam elements to calculate the spatial pose of the rotor. The calculation is performed repeatedly as the rotation angle increased to get the rotation trajectories of concerned nodes, and further evaluation is done to get the rotation accuracy. Additionally, to get more reliable results, the bearing motion errors and stiffness are analyzed by a static model considering manufacturing errors of parts.

The feasibility of the proposed method is verified through a case study of a high-precision spindle. The method reasonably predicts the rotation accuracy of the spindle.

For rotating machinery with multi-support structures, the paper proposes a modeling method to predict the rotation accuracy, simultaneously considering geometric errors and assembly deformation of parts. This would improve the accuracy of tolerance analysis.

In order to make sure of the safety of a long-span suspension bridge under earthquake action, this paper aims to study the traveling wave effect of the bridge under multi-support excitation and optimize the semi-active control schemes based on magneto-rheological (MR) dampers considering reference index as well as economical efficiency.

The finite element model of the long-span suspension bridge is established in MATLAB and ANSYS software, which includes different input currents and semi-active control conditions. Six apparent wave velocities are used to conduct non-linear time history analysis in order to consider the seismic response influence in primary members under traveling wave effect. The parameters α and β, which are key parameters of classical linear optimal control algorithm, are optimized and analyzed taking into account five different combinations to obtain the optimal control scheme.

When the apparent wave velocity is relatively small, the influence on the structural response is oscillatory. Along with the increase of the apparent wave velocity, the structural response is gradually approaching the response under uniform excitation. Semi-active control strategy based on MR dampers not only restrains the top displacement of main towers and relative displacement between towers and girders, but also affects the control effect of internal forces. For classical linear optimal control algorithm, the values of two parameters (α and β) are 100 and 8 × 10–6 considering the optimal control effect and economical efficiency.

The emphasis of this study is the traveling wave effect of the triple-tower suspension bridge under multi-support excitation. Meanwhile, the optimized parameters of semi-active control schemes using MR dampers have been obtained, providing relevant references in improving the seismic performance of three-tower suspension bridge.

This paper aims to present an investigation into the variation of scan vector hatch rotation strategies in selective laser melting (SLM), focussing on how it effects density, surface roughness, tensile strength and residual stress.

First the optimum angle of hatch vector rotation is proposed by analysing the effect of different increment angles on distribution of scan vectors. Sectioning methods are then used to determine the effect that the chosen strategies have on the density of the parts. The top surface roughness was analysed using optical metrology, and the tensile properties were determined using uni-axial tensile testing. Finally, a novel multi-support deflection geometry was used to quantify the effects of rotation angles on residual stress.

The results of this research showed that the hatch rotation angle had little effect on the density, top surface roughness and strength of the parts. The greatest residual stress deflection was measured parallel to unidirectional scan vectors. The use of hatch rotations other than alternating 90° showed little benefit in lowering the magnitude of residual stresses. However, the use of rotation angles with a good suitability measure distributes stresses in all directions more evenly for certain part geometries.

All samples produced in this work were made from commercially pure titanium, therefore care must be taken when applying these results to other materials.

This paper serves to increase the understanding of SLM scanning strategies and their effect on the properties of the material.

This study aims to investigate the extent and trends of voluntary corporate social responsibility (CSR) disclosure and to analyze the determinants of the listed banks’ annual reports and websites in an emergent capital market, namely, Tunisia.

The authors examine the level of CSR disclosure by means of a manual content analysis where the sentence is used as the unit of the analysis. They use Branco and Rodrigues’ (2006 and 2008) index which includes 23 items. They focus on the annual reports of 11 Tunisian listed banks during the period from 2007 to 2012 and the information presented on their websites in December 2013. They use, also, regression analysis to identify the determinants of CSR disclosure used by Tunisian listed banks.

The results of the investigation show that Tunisian listed banks disclose CSR information primarily in a narrative form. Human resources are the main focus in the annual reports, whereas, on the websites, community involvement is the most widespread theme. With regard to the determinants, it appears that bank age, financial performance and state shareholding are the main factors that impact CSR disclosure in the Tunisian listed banks’ annual reports. Furthermore, this study finds a positive (negative) relationship between leverage (financial performance) and CSR disclosure in the banks’ websites. In this regard, the results show different determinants of CSR disclosure for the two supports. Moreover, bank size, foreign shareholding and the type of auditor are unrelated to the listed banks’ CSR disclosure either in their annual reports or on their websites.

The sample size is small; however, it consists of all the relevant Tunisian banks. Also, this study is subject to the limitations of using manual content analysis.

This study enables highlights the importance of CSR disclosure and its determinants for the Tunisian banks’ stakeholders (such as regulators, investors and managers).

The authors contribute to the scarce literature on CSR disclosure in financial institutions. It is the first study to investigate Tunisian listed banks’ CSR disclosure. It is a first attempt to show, also, how banks’ characteristics and banks’ ownership structures impact on their CSR disclosure in their annual reports and on their websites.

The paper aims to develop a robot that climbs on non‐ferrous surfaces, e.g. aircraft wings and fuselages, carrying a heavy payload up to 18 kg including scanning arm and various equipments, for non‐destructive testing (NDT).

This robot in the study uses vacuum suction cups for adhesion, and two pairs of pneumatic cylinders to drive itself, moving in two directions in stepping gait. A rotation mechanism in the centre is used to correct the off‐course deviations by ± 5 degrees. Multiple universal joints are used to make every single suction cup, every robot foot and the whole structure flexible to negotiate with varying surface curvatures presented in different parts of aircraft. This flexible structure is also rigid once the robot is stuck on the surface to enable the NDT inspection being carried out reliably.

The paper finds that the walking speed is limited by the cylinder stroke, time for generating vacuum and changing legs. Although most NDT inspection is time‐consumable, it is still desirable to increase the robot speed.

The application of this robotic NDT can significantly reduce the cost of aircraft inspection, eliminate labour‐intensive and monotonous inspection tasks and eliminate the need for an operator to work in confined and dangerous spaces.

The paper introduces the structure that combines flexibility and rigidity for a robot climbing on non‐ferrous curvatures.

In stereolithgraphy rapid prototyping, the support can constrain the model deformation and avoid a lot of problems such as collapse, shift, and imbalance of the model. The support automatic generation algorithm has become the key research of rapid prototyping technics software; however, presently the efficiency of support automatic generation algorithm is low, and its algorithm is complex. Thus, it is of great importance in improving the overall efficiency of rapid prototyping technics software through enhancing the support generation efficiency. This paper aims to address these issues.

Based on this, this paper proposes a discrete‐marking support algorithm for treatment of processing on manufactured part model of all triangle‐based discrete‐marking on the support plane, which realizes the three‐dimensional computation of intersection for each line associated with the triangle automatically, and avoid invalid computation between all the support lines and other triangles.

The algorithm efficiency has reached O(n). Meanwhile, the technics support generation speed has been improved. Furthermore, the new mesh discrete‐marking and automatic support generation algorithm has been successfully applied to the sterolithography apparatus and selective laser melting of HRPS series.

Practical application indicates that the new support generation algorithm based on discrete‐marking considerably improves the support technics efficiency and stereolithgraphy rapid prototyping efficiency of the technics software.

The research presents a Noval support fast generation algorithm based on discrete‐marking in stereolithgraphy rapid prototyping.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council and publications of other similar Research Bodies as issued.

The aim of this paper is to review, briefly and selectively, some highlights of the progress made in the development of damping materials technology for vibration control, in the past two decades, with particular emphasis on the developments sponsored by the US Air Force Materials Laboratory at Wright‐Patterson Air Force Base.

Assembly accuracy is the guarantee of mechanical product performance, and the characterization of the part with geometrical deviations is the basis of assembly accuracy analysis.

The existed small displacement torsors (SDT) model cannot fully describe the part with multiple mating surfaces, which increases the difficulty of accuracy analysis. This paper proposed an integrated characterization method for accuracy analysis. By analyzing the internal coupling relationship of the different geometrical deviations in a single part, the Monomer Model was established.

The effectiveness of the Monomer Model is verified through an analysis of a simulated rotor assembly analysis, and the corresponding accuracy analysis method based on the model reasonably predicts the assembly deviation of the rotor.

The Monomer Model realizes the reverse calculation of assembly deformation for the first time, which can be used to identify the weak links that affect the assembly accuracy, thus support the accuracy improvement in the re-assembly stage.

Higher education institutions (HEIs) play a pivotal role in fostering economic development by cultivating skilled workforce and generating knowledge and innovation. However, HEIs may pose a potential risk to sustainable economic development due to the generation of food waste inside their campus canteens. Therefore, this study aims to examine the influence of attitude, subjective norm (SN), perceived behavior control (PBC), religiosity and pro-social behavior among State Islamic Religious College (SIRC) students on their intention to avoid food waste behavior. This study also focused on the mediating role of the three original theory of planned behavior (TPB) variables and pro-social behavior in the relationship between religiosity and the intention to reduce food waste.

Questionnaires were used to collect data from 443 students at SIRC. The collected data were processed and analyzed using structural equation modelling to test direct, indirect and mediating effects.

The empirical results indicated that the eagerness of students at SIRC to reduce their behavior of leaving food behind can be driven by their negative attitudes or views toward food waste, the practice of religious teachings in their lives, the belief that they can avoid food waste and their concern for the environment. The empirical results reveal that even though religiosity influences SN, it is unable to strengthen the relationship between religiosity and the desire to be anti-food waste.

In addition to contributing to the food waste literature in the context of eating behavior, the results of this study have theoretical and practical implications.

To assess SIRC students’ behavioral intentions to avoid food waste behavior, this study used a contemporary setting to measure attitude, SN, PBC, religiosity and pro-social behavior, so strengthening the TPB’s empirical underpinning.