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The image of the construction industry in China, as in many other countries, is tarnished by its poor safety record. With the rapid development of subway systems in Chinese urban areas, construction workers are being exposed to new risks which are poorly understood and managed. Subway construction projects are large scale and scattered over many construction sites, and involve numerous stakeholders and sophisticated technologies in challenging underground environments. Accident rates are high and have significant economic and social consequences for the firms and people involved. Addressing the gap in research about the safety risk in these projects, the purpose of this paper is to advance understanding of the factors influencing the safety of Chinese subway construction projects with the overall objective of reducing accident rates.

A survey was conducted with 399 subway construction professionals across five stakeholder groups. Follow-up interviews were also conducted with five experienced experts in safety management on subway projects to validate the results.

It was found that the eight most critical factors perceived by stakeholders to influence safety risks on Chinese subway projects are: project management team; contractor-related factors; site underground environment; safety protection during the use of machines; safety management investment; site construction monitoring and measurement; hazard identification and communication; and use of machines in all stages. This indicates that in allocating limited project resources to improve the safety of subway projects, managers should focus on: developing safety knowledge and positive attitudes in leadership teams; formulating effective risk management systems to identify, assess, mitigate, measure and monitor safety risks on site; improving communications with stakeholders about these risks and effectively managing plant, equipment and machinery.

This research contributes a new multi-stakeholder perspective to the lack of safety research in Chinese subway construction projects. The research findings provide important new insights for policymakers and managers in improving safety outcomes on these major projects, producing potentially significant social and economic benefits for society and the construction industry.

The purpose of this paper is to simulate the tension process of tension-type anchor cable and to explore the mechanical characteristics and tension-torsion coupling effect of anchor cable subjected to tension.

ABAQUS numerical software is applied to construct the numerical models of tension-type anchor cables with different diameters. Through explicit contact, the characteristics of contact between grouting body-anchor cable and grouting body-rock mass are determined. Confining pressure is applied to the model through surface pressure, and drawing force is applied to the model by displacement loading so as to simulate the tension process of the anchor cable.

The results show that the stress is transmitted in both axial and radial directions in the anchorage section and distributed in a cone. The shear stress in the grouting body is unevenly distributed, and its peak value increases with the rise in confining pressure and anchor cable diameter. The stress characteristics of torque and axial force are basically consistent and evenly distributed in the free section; they gradually decrease in the anchorage section. Due to the tension-torsion coupling effect, the internal stress characteristics of the anchor cable structure vary. On average, the anchorage performance of each anchor cable model is improved by 6.19%.

The proposed method of numerical modelling is effective in addressing the interface contact between the anchor cable and the grouting body and in solving the problem with convergence of calculation. Compared with the indoor test, this method is more suited to collecting the internal mechanical data of the anchor body.

The purpose of this paper is to examine dynamic mapping of holding locations to the animated maps in a library catalog which aims to resolve complex shelving situations, augment the user experience in locating library materials and enrich the Online Public Access Catalog (OPAC) by integrating external programming into the Integrated Library System (ILS).

Dynamic mapping displays animated direction maps for users to locate quickly the items found in the library catalog. The maps are displayed in accordance with various shelving policies. At Wichita State University Libraries, the original bibliographic data are captured from the record results page in the OPAC and transferred to a processing program residing on another server. Instead of transferring ISBN/ISSN (International Standard Book Number/ International Standard Serial Number, as practiced by some libraries) to display the Syndetic cover images, it transfers bibliographic ID and a few other fields from MARC (MAchine‐Readable Cataloging) records to a processing program which queries the ILS database for extracting data needed for the dynamic map processing. The dynamic map system consists of three sections: queried data from the ILS database, programming logic, and dynamic maps.

Compared to title‐level shelving map displays that have been implemented in some libraries, holding level map displays solve the problem of complex shelving situations, such as a title with multiple copies shelved in different locations and/or in different formats.

This project received very positive feedback from the library community and this paper will provide information to those libraries which are interested in dynamically presenting holding information in their OPAC.

This study aims to investigate whether the increasing robot adoption will affect employment rate and wages to contribute to the economic cycle and sustainable development in the world.

The authors introduce a two-way fixed effect model and ordinary least-squares (OLS) model to evaluate the influence based on relevant data of the eighteen countries with the largest robot stocks and robot densities in the world from 2006 to 2019 to test the influences and do the robustness test and endogeneity test by using empirical models.

The authors’ research findings suggest that increasing robot adoption can cause strong negative impacts on employment for both males and females in these economies. Second, the effect of robots on reducing job opportunities has penetrated different industries. It means that this negative impact of robots is comprehensive for the industry. Third, robot adoption can have a strong positive influence on wages and increase workers' incomes.

The limitations of the study are that the influence of industrial intelligence technologies on the circular economy is diversities in different countries. Thus, this study should consider the development levels of different economies to do additional confirmatory studies.

This study makes out the correlations between industrial robots and the employment market from the circular economy perspective. The result proves the existence of this influence relationship, and the authors propose some suggestions to promote sustainable economic development.

This paper addresses the activity of industrial intelligence technologies in the labor market. The employment market is an important part of the circular economy, and it will benefit social development if the government provides appropriate guidance for social investment and industrial layout.

This study is one of the few studies which considered the impact of industrial robots on employment and wages from the perspective of different industries, and this is very important for the circular economy in the world. The results of this paper provide an instructive reference for government policymakers and other countries to stabilize the labor market and optimize human resources for sustainable economic development.

The main purpose of this study is to fill the research gap on how B2B global service firms integrate dynamic capabilities within their omnichannel management to influence positive word of mouth (WOM), customer engagement (CE) and customer equity.

Drawing on the dynamic capability and WOM theories, a model has been developed that defines the subjects of the empirical test. The paper reports on data collected from 312 service-oriented global firms in Australia, through a cross-sectional survey. Data were analyzed using structural equation modeling.

The findings suggest that content management (i.e. information consistency, source trustworthiness and endorsement) and concerns management (i.e. privacy, security and recovery) capabilities are the two significant antecedents of positive WOM within a B2B omnichannel setting in international marketing. The findings also confirm the key mediating role of CE between positive WOM and customer equity.

The findings extend dynamic capability theory in the context of international marketing by linking WOM, CE and customer equity. The findings add further theoretical rigor by establishing the nomological chain between positive WOM and customer equity, in which CE plays a key mediating role.

This paper aims to first apply more advanced anisotropic yield criterions as Yld91 and Yld2004 to spherical indentation simulations, and investigate plastic anisotropy identified from indentation simulations following different yield criterions (Hill48, Yld91, Yld2004) to discover laws. It also aims to compare the difference in plastic anisotropy identified from indentation on three yield criterions and evaluate the applicability of plastic anisotropy.

This paper uses indentation simulations on different yield criterions to identify plastic anisotropy. First, the trust-region techniques based on the nonlinear least-squares method are used to determine anisotropy coefficients of Yld91 and Yld2004. Then, Yld91 and Yld2004 are implemented into ABAQUS software using user-defined material (UMAT) subroutines with the proposed universal structure. Finally, through considering comprehensively the key factors, the locations of the optimal data acquisition points in indentation simulations on different yield criterions are determined. And, the identified stress–strain curves are compared with experimental data.

This paper discovers that indentation on Yld2004 is able to fully identify difference in equivalent plastic strain between 0° and 90° directions when indentation depth h_t is relatively smaller. And, this research demonstrates conclusively that plastic anisotropy identified from indentation on Yld2004 and Yld91 is more applicable at larger strains than that on Hill48, and that on Yld2004 is more applicable than that on Yld91, overall. In addition, the method on the determination of the locations of the optimal data acquisition points is demonstrated to be also valid for anisotropic material.

This paper first investigates plastic anisotropic properties and laws identified from indentation simulations following more advanced anisotropic yield criterions and provides reference for later research.

Delta robot is a parallel robot specifically designed for high-speed pick and place tasks. However, sometimes they are asked to perform additional assembling and squeezing actions, which is beyond the capability of position-controlled Delta robots. Force sensors may be expensive and add mass to the system. Therefore, the purpose of this paper is to study sensorless force control of Delta robots using limited access interface.

Static force analysis is performed to establish a relation between joint torques and external forces. The joint torques are observed from signals provided by motor drivers. A distributed mass model is proposed to compensate the gravity of upper arms and forearms. To minimize the effect of backlash and nonlinear frictions brought by gearboxes, model parameters are calibrated in two separated modes: “LIFTING” and “LOWERING”. Finally, a hybrid force estimation model is built to deal with both cases simultaneously. Surrogate model-based force control law is proposed to increase the force control loop rate and handle the force control problem for discrete position-controlled Delta robots.

The results show that the force estimation model is effective and mode separation can significantly improve the accuracy. The force control laws indeed stabilize the robot in desired states.

The proposed solution is based on position-controlled commercial Delta robot and requires no additional force sensor. It is able to extend Delta robots’ capability and meet requirements of emerging complex tasks.

To the industrial application of intelligent and connected vehicles (ICVs), the robustness and accuracy of environmental perception are critical in challenging conditions. However, the accuracy of perception is closely related to the performance of sensors configured on the vehicle. To enhance sensors’ performance further to improve the accuracy of environmental perception, this paper aims to introduce an obstacle detection method based on the depth fusion of lidar and radar in challenging conditions, which could reduce the false rate resulting from sensors’ misdetection.

Firstly, a multi-layer self-calibration method is proposed based on the spatial and temporal relationships. Next, a depth fusion model is proposed to improve the performance of obstacle detection in challenging conditions. Finally, the study tests are carried out in challenging conditions, including straight unstructured road, unstructured road with rough surface and unstructured road with heavy dust or mist.

The experimental tests in challenging conditions demonstrate that the depth fusion model, comparing with the use of a single sensor, can filter out the false alarm of radar and point clouds of dust or mist received by lidar. So, the accuracy of objects detection is also improved under challenging conditions.

A multi-layer self-calibration method is conducive to improve the accuracy of the calibration and reduce the workload of manual calibration. Next, a depth fusion model based on lidar and radar can effectively get high precision by way of filtering out the false alarm of radar and point clouds of dust or mist received by lidar, which could improve ICVs’ performance in challenging conditions.

Based on virtual maintenance, this paper aims to propose a time prediction method of assembly and disassembly (A&D) actions of product maintenance process to enhance existing methods’ prediction accuracy, applicability and efficiency.

First, a framework of A&D time prediction model is constructed, which describes the time prediction process in detail. Then, basic maintenance motions which can comprise a whole A&D process are classified into five categories: body movement, working posture change, upper limb movement, operation and grasp/placement. A standard posture library is developed based on the classification. Next, according to motion characteristics, different time prediction methods for each motion category are proposed based on virtual maintenance simulation, modular arrangement of predetermined time standard theory and the statistics acquired from motion experiment. Finally, time correction based on the quantitative evaluation method of motion time influence factors is studied so that A&D time could be predicted with more accuracy.

Case study of time prediction of products’ various A&D processes is conducted by implementing the proposed method. The prediction process of diesel cooling fan disassemble time is presented in detail. Through comparison, the advantages and effectiveness of the method are demonstrated.

This paper proposes a more accurate, efficient and applicable product A&D time prediction method. It can help designers predict A&D time of a product maintenance accurately in early design phases without a physical prototype. It can also provide basis for the verification of maintainability, the balance of the design of product structure and system layout.