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Additive manufacturing is a fabrication technology with flexibility and economy. 18Ni300 is one of maraging steels with ultra-high strength, superior toughness, so it is an excellent candidate of structural material. This paper aims to explore the feasibility of using direct laser metal deposition method to fabricate18Ni300, and the evolution of its microstructure and defects is studied.

The experiments were conceived from single-trace-single-layer (STSL) test to multi-trace-multi-layers (MTML) test via single-trace-multi-layers (STML) test. The microstructure, defects and mechanical properties were analyzed.

The STML results showed that the columnar/equiaxed transformation occurred at the top part and the grain size increased with the layer number increasing, and it was explained by an innovative attempt combining columnar/equiaxed transformation model and the change of grain size. The MTML test with the interlayer orthogonal parallel reciprocating scanning pattern resulted in the grain growing along orthogonal directions; with the increase of overlap rate, the length and the area of the columnar grain decreased. What is more, the later deposition layer had lower micro-hardness value because of heat history.

Direct laser metal deposition method was a novel additive manufacturing method to manufacture 18Ni300 components, as 18Ni300 maraging steel was mainly manufactured by selective laser melting (SLM) method nowadays. It was useful to manufacture maraging steel parts using direct laser deposition method because it could manufacture larger parts than SLM method. Influence of processing parameters on forming quality and microstructure evolution was studied. The findings will be helpful to understand the forming mechanism of laser additive manufacturing of 18Ni300 components.

This paper aims to explore the influences of different process parameters, including laser power, scanning speed, defocusing distance and scanning mode, on the shape features of molten pool and, based on the obtained relationship, realize the diagnosis of forming defects during the process.

Molten pool was captured on-line based on a coaxial CCD camera mounted on the welding head, then image processing algorithms were developed to obtain melt pool features that could reflect the forming status, and it suggested that the molten pool area was the most sensitive characteristic. The influence of the processing parameters such as laser power, traverse speed, powder feed rate, defocusing distance and the melt pool area was studied, and then the melt pool area was used as the characteristic to detect the forming defects during the cladding and additive manufacturing process.

The influences of different process parameters on molten pool area were explored. Based on the relationship, different types of defects were accurately detected through analyzing the relationship between the molten pool area and time.

The findings would be helpful for the quality control of laser additive manufacturing.

This paper aims to examine the issue of promoting women managers at an enterprise level in China by tackling key research questions related to the level of participation of women among total managerial positions and the opportunities of promoting women into managerial position.

By conducting a questionnaire survey and analysing the results from 296 women managers who were taking MBA and EMBA programmes in China, the authors were able to obtain the sufficient sample size, as well as sufficient responses, given that these people who were taking MBA and EMBA studies required three to eight years of managerial work experience. Key questions are related to the level of participation of women among total managerial positions, and the criteria for women to be promoted into managerial positions. In addition, other issues such as the satisfaction of women managers towards promotion opportunities and career development and enterprise policies on women leadership are also important and need to be explored in this article. It is also useful to ask their views on the difference between men and women regarding individual efforts leading to promotion opportunities, and to check for any influence of pregnancy and other factors on women managers’ leadership roles.

The overall results achieved by analysing the results from 296 women managers who were taking MBA and EMBA programmes in China indicate that there has been positive improvement, with the majority of women managers being satisfied with the proportion of women as managers, and with their own promotion situations, in their current organizations.

The research project has some limitations. This paper focuses on key issues related to the promotion of women into management positions at an enterprise level through the interview and survey among those women managers who were taking MBA and EMBA programs. This research project did not include many issues that can be found among other women managers or issues at the society level, such as traditional culture and the influence of religion, or overall legislation regarding equal opportunity for women in the society, as the focus was on the experiences and expectations of individual women managers in the workplace.

Most people believed that social relationship, guanxi, is the most important factor in the promotion of women, but the findings in this paper show that the capabilities and achievements of women are more important than just having a good guanxi. This also inspires women to believe in themselves and believe that they can achieve their goals through their own effort. Other empirical implications, such as the negative influence of pregnancy on the current managerial positions and promotion opportunities for women, are evident, and the lack of policy initiative to address this issue causes a great degree of uncertainty among women managers.

The majority of the surveyed targeted women managers felt confident about their capability to be leaders, while most of them felt satisfied regarding the proportion of women managers in their organization, as well as their own current promotion situation. However, the “glass ceiling” phenomenon still exists, given most highly educated women managers believed it would be difficult to be promoted even further.

Through this article, the readers are firstly informed about the perceptions held by women managers in China nowadays regarding their promotion opportunities and career satisfaction. Secondly, the paper provides some understanding in the context of China’s reform from traditional planning system to the current market-oriented one, the associated change of business culture and the transformation of human resource management system and gender equality at the firm level.

The purpose of this study is to examine the impact of cross-ownership on corporate digital innovation and their specific mechanisms. Cross-ownership, who hold equity in two or more companies simultaneously, have two different types of governance effects in the capital market: governance synergistic effects and competitive collusion effects.

This paper uses a panel model, selecting A-share company data from 2011 to 2021 in China. In total, 23,853 valid data were obtained, which came from the CSMAR database and Wind database. For some missing data, they were manually supplemented by consulting the company's annual report and Sina Finance. Data processing was conducted using EXCEL and Stata16.0 software.

The results show that cross-ownership promote corporate digital innovation by leveraging governance synergies. Further grouping tests show that the synergistic effects of cross-ownership are significant in non-state-owned, high-tech, weakly competitive and higher analyst attention enterprises. Mechanism testing shows that cross-ownership can empower corporate digital innovation in three ways: reducing information asymmetry, alleviating financing constraints and improving corporate governance.

The conclusion of this paper provides new empirical evidence for a comprehensive understanding of the role of cross-ownership in corporate development, enriches the economic consequences research of chain institutional investors in China and broadens the research perspective of corporate digital innovation. It also provides important references for the digital transformation of enterprises and the healthy development of the capital market.

The existing research rarely explains the value of authoritarian leadership in small- and medium-sized enterprises (SMEs). The purpose of this study is to explore how authoritarian leadership facilitates employee followership behaviors of the SMEs in China by considering the moderating effects of cooperative goal interdependence and leader behavioral integrity.

This research tested hypotheses with a two-wave survey from a sample of 258 respondents from SMEs in China. Hypotheses are tested using hierarchical regression analyses.

Findings of the study have indicated the instrumental function of authoritarian leadership in facilitating employee followership behavior in SMEs. In particular, this study shows that the influence of authoritarian leadership on followership behavior was positively related when employees have high cooperative goal interdependence with authoritarian leaders, and when employees perceive a leader's high behavioral integrity.

The study will help SMEs to understand that authoritarian leadership should seek optimal levels of cooperative goals with employees and integrate achievement goals into their career development strategy to enhance their followership behavior. In addition, authoritarian leadership should strive to take actions consistent with their words to guarantee the relationship between achieving goals and sharing mutual goals with employees.

The study contributes to the literature by addressing an important yet under-researched area, i.e. the effectiveness of authoritarian leadership in SMEs. Authoritarian leadership, a demanding and controlling leadership style, is often criticized by scholars. This study elaborates on a three-way interaction implied by self-determination theory in predicting followership behavior. It specifies the different roles of two situational factors (cooperative goal interdependence and leader behavior integrity) in affecting employees' followership behavior.

The purpose of this study which resulted in this work is to propose an optimization method of sensors distribution for structural impact localization.

This paper presents a multi-objective optimization study of a novel sensors distribution technique, where two optimization objective functions are considered: sensors number and sensors location optimization performance index. In addition, the finite element analysis, the time-frequency transform and the principal component analysis are combined to quantize the above objective functions. The non-dominated sorting genetic algorithm II (NSGA-II) is used to acquire Pareto solutions.

The effectiveness of this method is validated through a prototype laboratory called the piezoelectric intelligent structure where promising results are obtained.

An optimization method of this novel sensors distribution technique is built and produced a set of efficiency solutions for the real-world problem of impact localization where two conflicting objectives are involved.

As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous expansion of the application of AM materials, subtractive processing has become one of the necessary steps to improve the accuracy and performance of parts. In this paper, the processing process of AM materials is discussed in depth, and the surface integrity problem caused by it is discussed.

Firstly, we listed and analyzed the characterization parameters of metal surface integrity and its influence on the performance of parts and then introduced the application of integrated processing of metal adding and subtracting materials and the influence of different processing forms on the surface integrity of parts. The surface of the trial-cut material is detected and analyzed, and the surface of the integrated processing of adding and subtracting materials is compared with that of the pure processing of reducing materials, so that the corresponding conclusions are obtained.

In this process, we also found some surface integrity problems, such as knife marks, residual stress and thermal effects. These problems may have a potential negative impact on the performance of the final parts. In processing, we can try to use other integrated processing technologies of adding and subtracting materials, try to combine various integrated processing technologies of adding and subtracting materials, or consider exploring more efficient AM technology to improve processing efficiency. We can also consider adopting production process optimization measures to reduce the processing cost of adding and subtracting materials.

With the gradual improvement of the requirements for the surface quality of parts in the production process and the in-depth implementation of sustainable manufacturing, the demand for integrated processing of metal addition and subtraction materials is likely to continue to grow in the future. By deeply understanding and studying the problems of material reduction and surface integrity of AM materials, we can better meet the challenges in the manufacturing process and improve the quality and performance of parts. This research is very important for promoting the development of manufacturing technology and achieving success in practical application.

This paper aims to investigate effect of porous polystyrene microspheres encapsulated inhibitor on the protection performance of epoxy resin coating.

Porous polystyrene (PS) microspheres were synthesized by soap-free emulsion polymerization. The morphology of microspheres was observed by scanning electron microscopy and transmission electron microscopy. Corrosion inhibitor benzotriazole was encapsulated into porous PS microspheres. The protection performance of epoxy resin coating with different contents of PS microspheres was tested by polarization curve.

The findings of electrochemical impedance spectroscopy and scanning vibrating electrode technique showed that addition of corrosion inhibitor to porous PS microspheres further improved the protection performance of the coatings.

Porous PS microspheres could be used as nanocontainer to encapsulate corrosion inhibitor.

Addition of porous PS microspheres with corrosion inhibitor improved the protection performance of the coatings.

Hand gesture-based interaction can provide far more intuitive, natural and immersive feelings for users to manipulate 3D objects for virtual assembly (VA). A mechanical assembly consists of mostly general-purpose machine elements or mechanical parts that can be defined into four types based on their geometric features and functionalities. For different types of machine elements, engineers formulate corresponding grasping gestures based on their domain knowledge or customs for ease of assembly. Therefore, this paper aims to support a virtual hand to assemble mechanical parts.

It proposes a novel glove-based virtual hand grasping approach for virtual mechanical assembly. The kinematic model of virtual hand is set up first by analyzing the hand structure and possible movements, and then four types of grasping gestures are defined with joint angles of fingers for connectors and three types of parts, respectively. The recognition of virtual hand grasping is developed based on collision detection and gesture matching. Moreover, stable grasping conditions are discussed.

A prototype system is designed and developed to implement the proposed approach. The case study on VA of a two-stage gear reducer demonstrates the functionality of the system. From the users’ feedback, it is found that more natural and stable hand grasping interaction for VA of mechanical parts can be achieved.

It proposes a novel glove-based virtual hand grasping approach for virtual mechanical assembly.

This paper aims to introduce a method to reduce corrosion caused by acidic-oxidized polymer degradant through subsection injection with different inhibitor.

This paper introduced a method to reduce corrosion caused by acidic-oxidized polymer degradant through subsection injection with different inhibitor.

The experimental results indicated that the influence of pre-corrosion status on corrosion rate and effectiveness of corrosion inhibitor are significant. The corrosion inhibitors in both injection stage inhibited the corrosion process by preventing the contact of corrosive medium and steel surface through formation of a protective film on the surface of N80 steel. The corrosion rate of polymer degradant can be reduced to 0.63 g/m 2 h through subsection injection with different inhibitor.

This result will increase the production of polymer injection plugging wells through expanding the application of acidic-oxidized polymer degradant.