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The weft-knitted two-side jacquard fabric has the characteristics of complicated design principle and hard technical design. The purpose of this paper is to realize the computer-aided design of weft-knitted two-side jacquard fabric, and provide a certain reference for the development of this type of fabric.

The weft-knitted two-side jacquard fabric is divided into weft-knitted two-side similar pattern jacquard fabric and weft-knitted two-side independent pattern jacquard fabric. In order to achieve the purpose of this study, firstly, the structural characteristic of weft-knitted two-side jacquard fabric is analyzed. Then, the design principle of weft-knitted two-side jacquard fabric is studied. Next, the technical model of weft-knitted two-side jacquard fabric is established. Finally, the CAD flow chart of weft-knitted two-side jacquard fabric is proposed to realize the rapid product development.

Based on the above method, through the development example of weft two-side similar pattern jacquard fabric and weft two-side independent pattern jacquard fabric, the computer-aided design of the weft two-side jacquard fabric is verified.

Because of limited research studies, three-dimensional computer-aided design of weft-knitted two-side jacquard fabric loop structure will be studied in the further research, and the technical design speed needs to be improved to meet the needs of large patterns and positioning patterns.

The computer-aided design of weft-knitted two-side jacquard fabric will offer a certain reference for product development, technical principles, performance research and computer simulation for the in-depth study of the fabric.

The computer-aided design of weft-knitted two-side jacquard fabric will simplify the fabric design process and improve the efficiency of new fabric development, and provide the industries a time-saving and cost-saving approach for new fabrics development.

The author analyzes the structural characteristic of the fabric by the physical fabric, summarizes design principle of the fabric through production process, uses mathematical methods to establish a three-dimensional technical model of the fabric, and proposes the CAD flow chart of weft-knitted two-side jacquard fabric, which has good theoretical significance and practice of weft-knitted two-side jacquard fabric.

This paper aims to calibrate the mounted parameters between the LIDAR and the motor in a low-cost 3D LIDAR device. It proposes the model of the aimed 3D LIDAR device and analyzes the influence of all mounted parameters. The study aims to find a way more accurate and simple to calibrate those mounted parameters.

This method minimizes the coplanarity and area of the plane scanned to estimate the mounted parameters. Within the method, the authors build different cost function for rotation parameters and translation parameters; thus, the parameter estimation problem of 4-degree-of-freedom (DOF) is decoupled into 2-DOF estimation problem, achieving the calibration of these two types of parameters.

This paper proposes a calibration method for accurately estimating the mounted parameters between a 2D LIDAR and rotating platform, which realizes the estimation of 2-DOF rotation parameters and 2-DOF translation parameters without additional hardware.

Unlike previous plane-based calibration techniques, the main advantage of the proposed method is that the algorithm can estimate the most and more accurate parameters with no more hardware.

This article has been withdrawn as it was published elsewhere and accidentally duplicated. The original article can be seen here: 10.1108/00022660410545483. When citing the article, please cite: Zhe-Min Wu, Chi Chen, Gao-Lian Liu, (2004), “Multipoint inverse shape design of airfoils based on variable-domain variational principle”, Aircraft Engineering and Aerospace Technology, Vol. 76 Iss: 4, pp. 376-38.

The purpose of this paper is to examine the impact of media attention on corporate disaster relief.

The authors used a matched sample research design, which is considered more appropriate than a random sample design for studying events that have low-occurrence rates in general. For each donor firm in the Yushu earthquake, the authors matched the firm with a non-donor firm in the same industry and with a firm size of within ±30 percent of the total assets in the year prior to the year of the occurrence of the Yushu earthquake. Then, using the Baidu engine, which is the most popular Chinese search engine, the authors captured the online media attention to the donor firms and their disaster relief.

The authors found that media attention drove corporate disaster relief.

Although the authors highlighted the role of the media as an important stakeholder in influencing corporate disaster relief, the authors did not fully explore the media’s influence. Future research should delve more deeply into the impact of the tenor of media coverage on corporate disaster relief.

This study reveals that the media, a particularly powerful stakeholder, can be a corporate disaster relief driver in China.

This paper aims to investigate the electrochemical corrosion behavior of a five-layer Al alloy composites (4343/4047/3003/4047/4343) with a thickness of 0.2 mm in NaCl solution.

Electrochemical impedance spectroscopy, polarization curve and morphology analyses were used to study the corrosion behavior of the Al alloy composites from cross-sectional and plane directions.

The corrosion resistance of the surface from the plane direction was higher than that from the cross sections. Si-enrich particles were observed in the outer 4047/4343 layer, and AlFeCuMnBi phases were identified in the core 3003 layer. The galvanic coupling between the Si-enrich particle and the Al matrix accelerated the dissolution Al matrix.

This work lays the experimental foundation for corrosion mechanism of the Al alloy composite plate.

In recent years, the ongoing development and rapid popularization of mobile devices, not only has brought new forms of lifestyle but also has boomed a wide array of service contents, allowing users to engage in entertainment, study and other daily activities, in addition to business transactions. To explore the factors that affect users' continued use of mobile app software, this paper aims to take into account the utilitarian value and privacy, as well as security factors and intends to propose an integrated research model based on the information systems success (ISS) model.

The data for this study were collected via an online survey questionnaire. A total of 190 valid responses were used to examine the hypotheses in the research model. The casual model was assessed using partial least squares techniques.

The results indicated that the three quality factors (information quality, system quality and service quality) in the ISS model significantly affected satisfaction and utilitarian value. Private and security have significant negative association with utilitarian value. The results also showed that private and security did not significantly affect satisfaction. The findings also provide some directions for further research.

The results show that user's continued use of mobile app software depends upon the perceived utilitarian value and satisfaction. The quality characteristics are the three critical factors that would affect the perceived utilitarian value and satisfaction. Compared to information quality and service quality, system quality has a higher degree of positive impact, which indicates that users are more concerned about the immediate download ability and ease-of-use provided by the system. Furthermore, the research also finds that privacy and security concerns have a negative influence on the utilitarian value, showing that in the context of task-oriented IS, the perceived risk of privacy and security during the process of using mobile app software services, will negatively affect users’ perception of utilitarian value. The insights provided by this study can help mobile app developers optimize design and marketing strategies.

This study provides a better understanding of how the factors in the theories influence the continuance usage intention of life style mobile applications.

This paper aims to study and modify the notch equivalent stress method, as well as to establish the notch equivalent stress range S–N curve and apply it to the fatigue assessment of engineering examples.

This paper studies the notch equivalent stress method and puts forward the concept of “singular equivalent crack”. Combined with the fatigue test results, by proposing to consider the singular coefficient of the transition angle of the welded structure and the introduction of material correction factors, this paper derives the notch equivalent stress equation for commonly used welded joints applicable to steel, and finally establishes the notch equivalent stress range of the S–N curve.

The obtained results show that the dispersion of fatigue data is 65.6 and 75.4% for T-joints and transverse cross-joints, respectively, under S–N curves using notched equivalent stress compared to the nominal stress range. The fatigue evaluation error of the modified notch equivalent stress equation for transverse cross welded joints improved by 50.65%, 53.1 and 39.6% on average, respectively, compared to the original other methods. The fatigue evaluation error for T-joints improved by 13.4 and 13.9%, respectively, compared to the original other methods.

There are relatively few studies on the fatigue assessment of notch equivalent stress method. In this paper, the notch equivalent stress method is studied and modified to improve the accuracy of fatigue assessment of welded structures with singular stresses.

This study examines the initiatives that would enable contractors in Singapore to improve the level of construction productivity.

A two-pronged research method was employed: questionnaire survey with contractors (109 responses received) and in-depth interviews with 12 subject matter experts. The questionnaire covered questions such as the current and future improvement measures.

The results show that the top three motives for achieving high productivity (increase profitability, on time delivery and enhance corporate competitiveness) are underpinned by profit maximization. Factor analysis revealed several categories of productivity improvement strategies. Among these, only site operations category is under the control of contractors. Other important categories include government's initiatives and design factors.

While contractors are the producers of built products, their productivity is very much dependent on other factors and other parties. The long-standing exhortation to contractors to improve productivity is necessary but not a sufficient condition to improve it.

Recommendations are provided for the government, designers, contractors and other stakeholders on what can be done to improve productivity.

This research adds to knowledge by showing that contractors' top motives for high productivity relate to self-seeking behavior to maximize profit. Prior to this study, productivity improvement is considered the responsibility of contractors. This study shows that two other stakeholders also hold the key to productivity improvement – government and designers. Government controls the supply of foreign labor, has the capacity to offer incentives and has the muscle to enact regulations to improve productivity. Consultants' upstream designs must be buildable.

This paper aims to facilitate the research and development of resilient navigation approaches, explore the robustness of adversarial training to different interferences and promote their practical applications in real complex environments.

In this paper, the authors first summarize the real accidents of self-driving cars and develop a set of methods to simulate challenging scenarios by introducing simulated disturbances and attacks into the input sensor data. Then a robust and transferable adversarial training approach is proposed to improve the performance and resilience of current navigation models, followed by a multi-modality fusion-based end-to-end navigation network to demonstrate real-world performance of the methods. In addition, an augmented self-driving simulator with designed evaluation metrics is built to evaluate navigation models.

Synthetical experiments in simulator demonstrate the robustness and transferability of the proposed adversarial training strategy. The simulation function flow can also be used for promoting any robust perception or navigation researches. Then a multi-modality fusion-based navigation framework is proposed as a light-weight model to evaluate the adversarial training method in real-world.

The adversarial training approach provides a transferable and robust enhancement for navigation models both in simulation and real-world.

As a kind of free (unknown) boundary problem, inverse shape design of airfoils has attracted extensive attention in recent years. By variable‐domain variational theory, free boundary condition can be coupled with the governing equations for flow field, which makes it possible to calculate the flow field with the free boundary simultaneously. In this paper, the variational principle (VP) of 2D airfoil shape design problem is obtained from the basic dimensionless velocity potential equations for 2D compressible flow by using a systematic approach and variable‐domain variational formula. The deformable finite element method based on the VP is used to segmentally design airfoil at two design points (angles of attack) and four design points, respectively. The results show that the present method is highly effective and accurate for solving multipoint inverse problem of airfoils.