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Based on the DVS1608-2011 and IIW-2008 and BS EN15085-3 standards, the stress state grade of welded joints of aluminum alloy EMU (Electric Multiple Units) body was studied.

First, the calculation methods of the stress state grade of aluminum alloy welded joints analyzed by DVS1608-2011 and IIW-2008 standards were studied, and the two methods were programmed by the APDL language of ANSYS. Then, the finite element model of aluminum alloy EMU body was established; the static strength calculation result of the body was compared with the test result, and the error is basically within 10%. Finally, under the acceleration fatigue load provided by BS EN12663 standard, the fatigue analysis was carried out on the welded joint of the vehicle body, and the stress state of the welded joint of the vehicle body was studied according to IIW-2008 and DVS1608 standards, respectively.

The results show that the assessment method based on IIW-2008 standard is more rigorous, and the maximum stress factor of the longitudinal weld between the side beam and the side wall is 0.811; the position occurs in the area where the longitudinal weld of the side beam and the side wall is close to the lower door angle.

The stress state is medium, and the rest of the weld stress states are low.

This paper aims to investigate the corrosion behavior of zinc in a typical hot and dry atmosphere. It proposes the dynamic corrosion for different exposure periods. Results can provide the basic data and corrosion mechanism of zinc in such environment.

In this paper, the authors investigated the corrosion behavior of pure zinc exposed in the typical hot and dry environment in Turpan for one-four years, which has never been studied. Scanning electron microscopy, laser scanning confocal microscopy, electron probe micro-analyzer (EPMA), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) were conducted to measure the corrosion morphology and products of zinc. Finally, combining electrochemical impedance spectroscopy and scanning Kelvin probe techniques, the corrosion mechanism of zinc in Turpan was examined.

The thickness loss of the zinc followed an exponential law with respect to exposure time: D = 3.17 t^0.61, and both of the rust layer resistance and the charge transfer resistance increased with exposure time. The corrosion products mainly comprised ZnO, Zn(OH)₂, Zn₅(CO₃)₂(OH)₆, Zn₄SO₄(OH)₆·5H₂O and Zn₁₂(SO₄)₃Cl₃(OH)₁₅·5H₂O. The Kelvin potentials shifted toward the positive direction from −0.380 to −0.262 V (vs saturated calomel electrode [SCE]) when the exposure time extended from one to four years and the distribution of the corrosion products became more and more uniform.

The corrosion behavior of pure zinc in the typical hot and dry environment in Turpan has not been studied. The dynamic corrosion for different exposure periods was obtained. The corrosion products were systemically investigated via energy-dispersive X-ray spectroscopy, EPMA, XPS and XRD.

The purpose of this exploratory study is to examine whether performance of microenterprises located in a microenterprise zone (MEZO) in China is positively related to key management practices, entrepreneurial orientation, marketing capability, and technology capability. The paper aims to introduce the concept of MEZOs as a supplemental tool for governments to strengthen microenterprise activity.

A total of 150 randomly selected microenterprises located in a MEZO in Changchun, an industrial city in Northeast China, completed a survey consisting of a three‐part measure of microenterprise performance developed by Zinger et al. and entrepreneurial orientation. Factor analysis was performed on 11 management issues and correlation analysis was performed.

The study found that key management practices, marketing capability, and technology capability of microenterprises in MEZOs do have a positive impact on performance sales, net profit, and growth.

The study's results are limited by a sample in one city in one province of China collected in one month. The data are cross‐sectional rather than longitudinal. Sample bias may exist.

This study is valuable to government officials, policy makers, non‐government organizations and consulting firms as they examine new measures to unleash the economic power of microenterprises.

MEZOs need to be explored as one solution to aide microenterprise development to improve the poverty level, create jobs, and stimulate economic activity.

To the authors' knowledge, this is the first exploratory study of the performance of microenterprises located in a MEZO in China. Through research, the factors that contribute to microenterprise performance and success can be better understood and the impact that the MEZO model has on microenterprises can be better delineated.

Since the opening of China (aka, reform and opening-up), a great number of rural residents have migrated to large cities in the past 40 years. Such a one-way population inflow to urban areas introduces nontrivial social conflicts between urban natives and migrant workers. This study aims to investigate the most discussed topics about migrant workers on Sina Weibo along with the corresponding sentiment divergence.

An exploratory-descriptive-explanatory research methodology is employed. The study explores the main topics on migrant workers discussed in social media via manual annotation. Subsequently, guided LDA, a semi-supervised topic modeling approach, is applied to describe the overall topical landscape. Finally, the authors verify their theoretical predictions with respect to the sentiment divergence pattern for each topic, using regression analysis.

The study identifies three most discussed topics on migrant workers, namely wage default, employment support and urban/rural development. The regression analysis reveals different diffusion patterns contingent on the nature of each topic. In particular, this study finds a positive association between urban/rural development and the sentiment divergence, while wage default exhibits an opposite relationship with sentiment divergence.

The authors combine unique characteristics of social media with well-established theories of social identity and framing, which are applied more to off-line contexts, to study a unique phenomenon of migrant workers in China. From a practical perspective, the results provide implications for the governance of urbanization-related social conflicts.

The purpose of this paper is to propose a multi-feature, multi-metric and multi-loop tightly coupled LiDAR-visual-inertial odometry, M³LVI, for high-accuracy and robust state estimation and mapping.

M³LVI is built atop a factor graph and composed of two subsystems, a LiDAR-inertial system (LIS) and a visual-inertial system (VIS). LIS implements multi-feature extraction on point cloud, and then multi-metric transformation estimation is implemented to realize LiDAR odometry. LiDAR-enhanced images and IMU pre-integration have been used in VIS to realize visual odometry, providing a reliable initial guess for LIS matching module. Location recognition is performed by a dual loop module combined with Bag of Words and LiDAR-Iris to correct accumulated drift. M³LVI also functions properly when one of the subsystems failed, which greatly increases the robustness in degraded environments.

Quantitative experiments were conducted on the KITTI data set and the campus data set to evaluate the M³LVI. The experimental results show the algorithm has higher pose estimation accuracy than existing methods.

The proposed method can greatly improve the positioning and mapping accuracy of AGV, and has an important impact on AGV material distribution, which is one of the most important applications of industrial robots.

M³LVI divides the original point cloud into six types, and uses multi-metric transformation estimation to estimate the state of robot and adopts factor graph optimization model to optimize the state estimation, which improves the accuracy of pose estimation. When one subsystem fails, the other system can complete the positioning work independently, which greatly increases the robustness in degraded environments.