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The purpose of this paper is to investigate the mechanical properties’ behaviors of woven composite cut-out structures with specific parameters. Because of the complexity of micro-scale and meso-scale structure, it is difficult to accurately predict the mechanical material behavior of woven composites. Numerical simulations are increasingly necessary for the design and optimization of test procedures for composite structures made by the woven composite. The results of the proposed method are well satisfied with the results obtained from the experiment and other studies. Moreover, parametric studies on different plates based on the stacking sequences are investigated.

A multi-scale modeling approach is suggested. Back-propagation neural networks (BPNN), radial basis function (RBF) and least square support vector regression are integrated with efficient global optimization (EGO) to reduce the weight of assigned structure. Optimization results are verified by finite element analysis.

Compared with other similar studies, the advantage of the suggested strategy uses homogenized properties behaviors with more complex analysis of woven composite structures. According to investigation results, it can be found that 450/−450 ply-orientation is the best buckling load value for all the cut-out shape requirements. According to the optimal results, the BPNN-EGO is the best candidate for the EGO to optimize the woven composite structures.

A multi-scale approach is used to investigate the mechanical properties of a complex woven composite material architecture. Buckling of different cut-out shapes with the same area is surveyed. According to investigation, 45°/−45° ply-orientation is the best for all cut-out shapes. Different surrogate models are integrated in EGO for optimization. The BPNN surrogate model is the best choice for EGO to optimization difficult problems of woven composite materials.

The purpose of study is to overcome the error estimation of standard deviation derived from Expected improvement (EI) criterion. Compared with other popular methods, a quantitative model assessment and analysis tool, termed high-dimensional model representation (HDMR), is suggested to be integrated with an EI-assisted sampling strategy.

To predict standard deviation directly, Kriging is imported. Furthermore, to compensate for the underestimation of error in the Kriging predictor, a Pareto frontier (PF)-EI (PFEI) criterion is also suggested. Compared with other surrogate-assisted optimization methods, the distinctive characteristic of HDMR is to disclose the correlations among component functions. If only low correlation terms are considered, the number of function evaluations for HDMR grows only polynomially with the number of input variables and correlative terms.

To validate the suggested method, various nonlinear and high-dimensional mathematical functions are tested. The results show the suggested method is potential for solving complicated real engineering problems.

In this study, the authors hope to integrate superiorities of PFEI and HDMR to improve optimization performance.

Roofing is one of the most dangerous jobs in the construction industry. Due to factors such as lack of planning, training and use of precaution, roofing contractors and workers continuously violate the fall protection standards enforced by the US Occupational Safety and Health Administration. A preferable way to alleviate this situation is automating the process of non-compliance checking of safety standards through measurements conducted in site daily accumulated videos and photos. As a key component, the purpose of this paper is to devise a method to detect roofs in site images that is indispensable for such automation process.

This method represents roof objects through image segmentation and visual feature extraction. The visual features include colour, texture, compactness, contrast and the presence of roof corner. A classification algorithm is selected to use the derived representation for statistical learning and detection.

The experiments led to detection accuracy of 97.50 per cent, with over 15 per cent improvement in comparison to conventional classifiers, signifying the effectiveness of the proposed method.

This study did not test on images of roofs in the following conditions: roofs initially built without apparent appearance (e.g. structural roof framing completed and undergoing the sheathing process) and flat, barrel and dome roofs. From a standpoint of construction safety, while the present work is vital, coupling with semantic representation and analysis is still needed to allow for risk analysis of fall violations on roof sites.

This study is the first to address roof detection in site images. Its findings provide a basis to enable semantic representation of roof site objects of interests (e.g. co-existence and correlation among roof site, roofer, guardrail and personal fall arrest system) that is needed to automate the non-compliance checking of safety standards on roof sites.

This paper aims to present two updated typologies of service failures and recoveries in the omni-channel context. These typologies are based on customer complaints and recoveries collected from the corporate Facebook pages of four omni-channel department stores, two operating in Australia and two in the UK.

A document review is used of 400 customer complaints and recoveries. Content analysis is used to condense the Facebook data into categories of failures and recoveries.

Customer complaints on Facebook were triggered by a multitude of varying failures in the omni-channel context, given that it is the service brand that customers are experiencing, not just retail channels. The most prevalent failures were “bricks and mortar” shopping, delivery, marketing activities including communications and pricing, quality of goods and customer service. For service recoveries on Facebook, the four-dimensional justice framework appears valid.

Study limitations include potentially missing details about the nature of the service failures and recoveries, including customer satisfaction with service recovery.

The typologies offer guidance to omni-channel retailers by showing the range of online and offline situations, including those unrelated to actual transactions that trigger customer complaints on Facebook and the tactics of recovering.

The authors contribute to the service domain by updating failure and recovery typologies to reflect the emerging omni-channel context, jointly exploring failures and recoveries on Facebook and applying a four-dimensional justice framework for recoveries on Facebook.

An analytical investigation has been carried out for a simply supported rectangular plate with two different loading conditions by using 3D state space approach (SSA). Also, the accurate location of the neutral plane (N.P.) through the thickness of the plate can be identified: the N.P. is shifted away from the middle plane according to the loading condition. The paper aims to discuss these issues.

SSA and finite element method are used for the determination of structural behaviour of simply supported orthotropic composite plates under different types of loading. The numerical results from a finite element model developed in ABAQUS.

The effect of the plate thickness on displacements and stresses is described quantitatively. It is found that the N.P. of the plate, identified according to the values of the in-plane stresses through the thickness direction, is shifted away from the middle plane. Further investigation shows that the position of the N.P. is loading dependant.

This paper describe the effect of the plate thickness on displacements and stresses quantitatively by using an exact solution called SSA. Also, it is found that the N.P. of the plate, identified according to the values of the in-plane stresses through the thickness direction, is shifted away from the middle plane. Further investigation shows that the position of the N.P. is loading dependant.

This research aims to explore the interactions of stakeholders in online food delivery (OFD) platforms, including restaurants, the delivery system and the platform, and the effect on total sales. In order to comprehensively analyze the service of stakeholders, the authors adopted the time duration which provides a unified metric for assessing service performance.

The authors used panel vector autoregressive (PVAR) model analysis to verify the interactions among restaurants, the delivery system, and the platform itself, and to assess their effects on the sales. Data were collected from one of the biggest OFD service platforms in China – Eleme.com.

First, the findings confirmed that the service performance of restaurants, the delivery system and the platform itself influence one another. There is a bidirectional causality between food preparation time (FPT) and actual delivery time (ACDT), as well as between FPT and advance arrival time (ADAT), ACDT and ADAT. Second, the service performance of restaurants, the delivery system, and the platform itself all positively affect sales, thus demonstrating unidirectional causality.

The current research is a pioneering empirical study, as it confirms the dynamic interactions between participants in OFD platforms and the dynamic influence of their respective service performances on sales. The findings of this research have a number of implications for the management and operation of online food ordering and delivery platforms.

This study investigates the effects of using social media for customer service on firms' reputation building. In addition, this study explores the role of absorptive capacity, ISO (International Organization for Standardization) 9,000 implementation and periodic training for management and employees in the relationship between social media–based customer service and firm reputation.

This study sampled 115 US-listed firms and collected secondary data from five databases as follows: Factiva, Fortune's World's Most Admired Companies (WMAC), Standard & Poor's COMPUSTAT, American Customer Satisfaction Index (ACSI) and Thomson Reuters’ Environmental, Social and Governance (ESG). This study developed a panel dataset of these 115 firms from 2007 to 2016 and conducted dynamic panel data analyses to examine the hypotheses.

This study finds that a higher number of social media channels used for customer service is associated with a higher reputation score for a firm. In addition, the positive relationship is reinforced when a firm has a high absorptive capacity level, an ISO 9000 quality management system and offers periodic training for management and employees.

To the best of our knowledge, this is the first study to investigate the relationship between social media–based customer service and firm reputation. This study also explores the boundary factors in terms of firm absorptive capacity, ISO 9000 quality management systems and training for management and employees.

The state space method (SSM) is good at analyzing the interfacial physical quantities in laminated materials, while it has difficulty in calculating the mechanical quantities of interior points, which can be easily evaluated by the boundary element method (BEM). However, the material has to be divided into many subdomains when the traditional BEM is applied to analyze the functionally graded material (FGM), so that the computational amount will be increased enormously. This study aims to couple these two methods to strengthen their advantages and overcome their disadvantages.

Herein, a state space BEM in which the SSM is coupled by the BEM is proposed to analyze the elasticity of FGMs, where one BEM domain is set and the others belong to SSM domains. The discretized elements occur only on the boundary of the BEM domain and at the interfaces between different SSM domains. In SSM domains, the horizontal interfaces of FGMs are discretized by linear elements and the variables along the vertical direction are yielded by the precise integration method.

The accuracy of the proposed method is verified by comparing the present results with the ones from the finite element method (FEM). It is found that the present method can provide accurate displacements and stresses in the FGMs by fewer freedom degrees in comparison with the FEM. In addition, the present method can provide continuous interfacial stresses at the interfaces between different material domains, while the interfacial stresses by the FEM are discontinuous.

The system equations of the state space BEM are built by combining the boundary integral equation with the state equations according to the continuity conditions at the interfaces. The mechanical parameters of any inner point can be evaluated by the boundary integral equation after the unknowns on the boundaries and interfaces are determined by the system equation.