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This paper aims to investigate a novel additive manufacturing (AM) method for titanium alloy using Joule heat as the single heat source to melt TC4 wire, which intends to provide a new low-power, low-cost solution for the processing of titanium alloys.

When current flows through the wire and the substrate, Joule heat will be generated to melt the wire and join the wire with the substrate. By stacking the wire layer by layer, finally a part can be formed. The cross-sectional morphology, microstructure and hardness of TC4 single track deposits formed by Joule heat melting wire AM were investigated by various characterization methods.

The melting width and melting penetration decreased with the increase of printing speeds. There is no obvious change in single track morphology with the change of printing pressures. The melting width and melting penetration increased with the increase of printing currents. The observation of the internal microstructure of a single track reveals a decrease in grain size as printing speeds increase. The average hardness of the single track was about 363 HV, which is comparable to the hardness of the parts fabricated by selective laser melting process. The printing power is less than 300 W, which is lower than other AM processes.

This paper provides a novel solution for the processing of titanium alloy parts. Compared with other expensive energy sources, this work only uses an ordinary DC power supply as the energy source. The printing process is simple and the cost is low. The power is much lower than other AM processes.

As coaching assumes an increasingly critical role in satisfying employees' demands for growth, the function of coaching has progressively shifted towards direct supervisors. This study seeks to investigate the distinct effects of managerial coaching behaviors on employee outcomes from an emotional perspective. Specifically, we aim to explore whether leaders' encourage-to-explore and guide-to-learn behaviors impact employees' creativity and performance through discrete emotional mechanisms upon appraisal theory of emotion.

We conducted two studies to test our proposition. In study 1, an experiment using coaching scenarios was performed with 128 students majoring in management. In study 2, data were collected from 311 supervisor-subordinate dyads.

The results indicate that encourage-to-explore behaviors are positively related to employee creativity by fostering feelings of inspiration, and guide-to-learn behaviors are positively related to employee performance by alleviating anxiety. These findings suggest that different leaders’ coaching behaviors influence employee outcomes through different emotional processes. The theoretical and practical implications of the findings are also discussed.

These findings suggest that different leaders’ coaching behaviors influence employee outcomes through different emotional processes. The theoretical and practical implications of the findings are also discussed.

The purpose of this paper is to investigate the effect of different soldering temperatures on the performance of chip-on-board (COB) light sources during vacuum reflow soldering.

First, the influence of the void ratio of the COB light source on the steady-state voltage, luminous flux, luminous efficiency and junction temperature has been explored at soldering temperatures of 250°C, 260°C, 270°C, 280°C and 290°C. The COB chip has also been tested for practical application and aging.

The results show that when the soldering temperature is 270°C, the void ratio of the soldering layer is only 5.1%, the junction temperature of the chip is only 76.52°C, and the luminous flux and luminous efficiency are the highest, and it has been observed that the luminous efficiency and average junction temperature of the chip are 107 lm/W and 72.3°C, respectively, which meets the requirements of street lights. After aging for 1,080 h, the light attenuation is 84.64% of the initial value, which indicates that it has higher reliability and longer life.

It can provide reference data for readers and people in this field and can be directly applied to practical engineering.

This study aims to study the mechanical, photoelectric, and thermal reliability of SAC307 solder joints with Ni-decorated MWCNTs for flip-chip light-emitting diode (LED) package component during aging. By adding nanoparticles (Ni-multi-walled carbon nanotubes [MWCNTs]) to the solder paste, the shear strength and fatigue resistance of the brazed joint can be improved. However, the aging properties of Ni-modified MWCNTs composite solder joints have not been deeply studied. In this research, the mechanical, photoelectric and thermal reliability of SAC307 packaged flip-chip LEDs with Ni-MWCNTs added during aging were studied.

Compared with SAC solder alloys, the effects of different contents (0, 0.05, 0.1 and 0.2 Wt.%) of Ni-MWCNTs on the photoelectric and thermal properties of composite solder joints were examined. To study the aging characteristics of composite solder joints, the solder joints were aged at 85°C/85% relative humidity.

The addition of an appropriate amount of reinforcing agent Ni-MWCNTs reduces the density of the composite solder to 96% of the theoretical value of the SAC solder alloy. In addition, the microhardness increases and the wetting angle decreases. Two different phase compositions were observed in the solder joints with Ni-MWCNTs reinforcement: Cu₃Sn and (Cu, Ni)₆Sn₅. The solder joints of SAC307-0.1Ni-MWCNTs exhibit the highest luminous flux and luminous efficiency of flip-chip LED filaments, the lowest steady-state voltage and junction temperature. And with the extension of the aging time, its aging stability is the best. In short, when the addition amount of Ni-MWCNTs is 0.1 Wt.%, the solder joints exhibit the best wettability and the thinnest intermetallic compound layer. And the shear strength of the tested solder joints is the best, and the void ratio is the lowest. At this time, the enhancement effect of Ni-MWCNTs on the composite solder has been best demonstrated.

The content range of enhancer Ni-MWCNTs needs to be further reduced.

The authors have improved the performance of Ni-modified MWCNTs composite solder joints.

Composite solder with high performance has great practical application significance for improving the reliability and life of the whole device.

The purpose of this study is to solve the issues of time-consuming and complicated computation of traditional measures, as well as the underutilization of two-dimensional (2D) phase-trajectory projection matrix, so a new set of features were proposed based on the projection of attractors trajectory to characterize the friction-induced attractors and to reveal the tribological behavior during the running-in process.

The frictional running-in experiments were conducted by sliding a ball against a static disk, and the friction coefficient was collected to reconstruct the friction-induced attractors. The projection of the attractors in 2D subspace was then mapped and the distribution of phase points was adapted to conduct the feature extraction.

The evolution of the proposed moment measures could be described as “initial rapid decrease/increase- midterm gradual decrease/increase- finally stable,” which could effectively reveal the convergence degree of the friction-induced attractors. Moreover, the measures could also describe the relative position of the attractors in phase–space domain, which reveal the amplitude evolution of signals to some extent.

The proposed measures could reveal the evolution of tribological behaviors during the running-in process and meet the more precise real-time running-in status identification.

An accurate and fast dynamic analysis innovative approach for vehicle parts is provided for engineering practice.

This paper presents an innovative dynamic analysis approach for vehicle parts based on parallel optimization algorithm with CUDA.

This project is supported by the National Science Foundation of China (No. 51805076, No. U1708255 and No. 51775093), the Fundamental Research Funds for the Central Universities (No. N170503011) and the Natural Science Foundation of Liaoning Province, China (No. 20180551058).

This paper presents an innovative approach for vehicle parts using parallel optimization algorithm based on CUDA, which can improve the computing accuracy and speed effectively.

This chapter has two central goals: (1) to present a foundational argument for status dissonance theory and (2) to apply its central propositions to understanding why some White Americans perceive anti-White bias. Building upon status construction theory, status dissonance theory generally posits that one’s overall status value determined by their combined status characteristics influences the degree they internalize normative referential structures. The salience of normative referential structures frames one’s justice perceptions, which creates status dissonance that manifests as a positional lens through which individuals perceive and interact with the social world. In an application of this framework, it is hypothesized that among Whites, one’s gender and class will impact one’s perceptions of resource reallocation (i.e., racial equality), which in turn impacts the likelihood one perceives anti-White bias generally and personally.

Using the Pew Research Center’s Racial Attitudes in America III Survey, this study employs logistic and ordered probit regressions on a nationally representative sample of White Americans to assess the above propositions.

Among Whites, males, those whom self-identified as lower class, and the least educated have the highest odds of perceiving resource re-allocation, and in turn all of these factors increased the odds of perceiving anti-White bias generally in society as well as perceiving personal encounters of “reverse” discrimination.

The findings and theoretical propositions provide a foundation for additional investigations into understanding the causes and consequences of within and between group variation in perceptions and responses to social inequality as well as mechanisms to counter status hierarchies.

The purpose of this paper is to assess the importance of group position and consciousness in predicting people’s perceptions of police fairness in China.

This study used survey data collected from 1,095 respondents in Shanghai. Multivariate regression was used to analyze the effects of group positions and group consciousness variables on perceived police fairness, controlling for personal, experiential and neighborhood factors.

Regardless of their own hukou status, individuals who live in high migrant areas expressed less favorable attitudes toward police fairness. Meanwhile, people who displayed greater degrees of sensitivity to bias in law rated police fairness less favorably, whereas people who expressed higher levels of moral alignment with the law and belief in no choice but to obey the police rated police fairness more favorably. Lower levels of neighborhood disorder and higher degrees of cohesion were also associated with more positive evaluations of police fairness.

The authors’ measure of migrant concentration was constructed based on respondents’ own assessments of this neighborhood feature. Future studies should consider using objective measures to supplement the construction of migrant concentration variables. The authors’ group consciousness variables are limited as they are general, non-residential status specific and only capture part of the traditionally conceptualized variable of group consciousness. Future study should employ better-worded items that can tap precisely into people’s various dimensions of social consciousness based on their group status.

Training officers has to give a high priority to the principles of both procedural and distributive justice, and implement performance and evaluation policies that support fair and responsive police behavior, particularly during situations where citizens report crime to and seek help from the police.

Despite their high relevance, variables reflecting group position have received marginal attention in previous research on public evaluations of the police in China. This study represents a first attempt to examine how the interactions between residence status and the level of neighborhood migrant concentration influence Chinese attitudes toward police fairness.

The unanticipated disruption caused by the ongoing coronavirus pandemic led to the extensive use of flexible working arrangements. In such a boundaryless work environment, however there are significant concerns, especially around inclusivity and discrimination. Given the increasing concerns surrounding hybrid and remote work settings, the authors investigated whether the extent of working in substantially flexible working arrangements relates to employees’ perceived ostracism and inequality, distinguishing between working from home, in a hybrid mode or from the office. In addition, the authors theorised that in flexible working arrangements, high-quality leader relationships, such as leader–member exchange (LMX) and servant leadership are likely to reduce perceptions of ostracism and inequality. Based on a survey of 161 professionals, who worked to varying degrees in flexible working arrangements, the authors found that employees who worked extensively in a hybrid mode were less likely to report experiences of ostracism and inequality in comparison to employees who worked mainly from home or in an office. Furthermore, a moderation analysis showed that the effects of LMX and servant leadership on perceptions of ostracism and inequality were much stronger for individuals who work in hybrid working arrangements than those who work at the office or from home. This research makes an important contribution to our understanding of how different degrees of flexible working arrangements affect employees by demonstrating the role of high-quality leader relationships in reducing perceptions of ostracism and inequality at different degrees of work flexibility.