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The construction industry is characterized by a long construction period, high cost and many uncontrollable factors. The owners and contractors are increasingly focusing on the efficiency of their construction and costs in pursuit of greater economic benefits. However, current methods used in the construction period and cost optimization analysis with multiple constraints the have their own limitations. Therefore, this study aims to propose a combination of genetic algorithm (GA) and building information modeling (BIM) to construct a five-dimensional construction duration-cost optimization model with the advantages of optimization and simulation for optimization.

This design first analyzed the characteristics of changing construction period and cost and then improved the genetic mechanism and the data processing method in the GA according to the aforementioned characteristics. Then, BIM technology was combined with GA to testify the feasibility of the model in the practical engineering project.

The result proved that this new method was reasonable and effective in dealing with the complicated problem of period and cost. GA accelerated the optimization process and yielded a reliable Pareto solution. BIM technology simulated the construction process before construction to increase the feasibility of the construction scheme.

This method not only can rapidly provide the best construction period/cost decision to the architect according to the previous working period/cost or contract data that can meet the demands of the architect but also visualize the construction and give a dynamic schedule of the project.

The purpose of this paper is to investigate the role of intrinsic motivation and self-construal in explaining the relationship between work-related identity discrepancy and employee innovation behavior.

Based on a survey of 637 respondents from 15 organizations in southern China, this study examines four hypotheses with regard to the relationship between work-related identity discrepancy and employee innovation behavior through hierarchical regression analysis.

The research results indicate that work-related identity discrepancy is negatively related to employee innovation behavior, but intrinsic motivation mediates their negative relationship, and self-construal moderates this mediating effect further. Specifically, the results demonstrate that perceiving work-related identity discrepancy can lower intrinsic motivation among employees with interdependent self-construal and subsequently reduce their innovation behavior.

Drawn on social cognitive theory, this study reveals the negative effect of work-related identity discrepancy on employee innovation behavior and the moderated mediation effect of intrinsic motivation and self-construal on the negative relationship. The finding expands existing literature on work-related identity discrepancy and employee innovation behavior.

Based on the conservation of resources theory, the authors explore the relationship between humble leadership and employee procrastination by introducing career calling and promotion focus, and constructing a moderated mediation model aiming to reveal the influence of humble leadership on employee procrastination.

A total of 217 valid samples were obtained using a two-time point paired questionnaire. The proposed hypotheses were tested using hierarchical regression.

Hierarchical regression results indicated that humble leadership had a significant negative effect on employee procrastination. Career calling played a fully mediating role in humble leadership and employee procrastination. Promotion focus not only plays a positive moderating role between humble leadership and career calling but also moderates the mediating role of career calling.

Managers should pay attention to the cultivation of their own character of humility in the process of communicating with their subordinates, increase employees' career calling from various aspects to improve employees’ sense of meaning and value for their work and understand employees' situation for personalized management.

This study reveals for the first time the inhibitory effect of humble leadership on employee procrastination through the conservation of resources theory. This helps in expanding research on the antecedents of procrastination behavior and enriching research on the effects of implementing humble leadership. For this reason, the study contributes to the literature on humble leadership, employee procrastination and the conservation of resources theory.

The authors designed those experiments to test the sensitivity of graphene when it is exposed to NO₂ gas, to find a way to decrease the recovery time of graphene and to find the difference effect between monolayer and bilayer graphene in the experiments.

The authors transferred graphene from film on Cu foil to NO₂ sensor sample and measured the resistances of on monolayer and bilayer graphene when they were exposed to NO₂ gas under different concentration; then, the authors obtained the results.

The results show that monolayer graphene exhibits a linear response when the NO₂ concentration is below 20 ppm. But the monolayer graphene will not be so sensitive to NO₂ gas when the concentration continues to reduce. The desorption time of monolayer graphene is longer when compared with bilayer graphene. It shows faster recovery time and higher response of bilayer graphene under low NO₂ concentration. And the limit detectable NO₂ concentration of bilayer graphene is 50 ppb. Desorption time of bilayer graphene is shortened to below 20 s under UV light.

The authors found a reliable way to decrease the recovery time of graphene when it is exposed NO₂ gas and got the concrete data.

The purpose of this study is to investigate the synergism of convection, current density distribution and additives by numerical simulation and electrochemical experiments for good throwing power (TP) of copper electro-deposition in printed circuit board (PCB) manufacture.

The flow field of THs and current density distribution on various AR of THs are calculated and analyzed. Meanwhile, corresponding simulation is used to study the performance of plating electrolytes on TP. Two electrochemical parameters, overpotential (η) and potential difference (△η), are chosen to evaluate the electrochemical properties of different plating solutions by galvanostatic measurement and potentiodynamic cathode polarization at different rotating speeds.

By combining both the results of simulation and practical plating, these two electrochemical properties of electrolytes exhibit significant impact to the system at varied conditions. Especially, the electrolyte with higher polarizing η and △η values lead to the elevated TP for AR of more than 2:1.

The harring cell model is built as a bridge between the theoretical and experimental study for control of uniformity of plating THs in PCB manufacturing. This dual-parameter evaluation is validated to be a promising decisive method to guide the THs plating with particular AR in industry.

The purpose of this paper is to form high density interconnection (HDI) of backboard for press-fit applications with the pre-curing conditions of conductive paste. The best condition of pre-curing conductive paste should be found to obtain good electrical and physical performance of the conductive paste and avoid the simultaneous curing behavior of prepreg.

A novel structure of backboard was designed by using the connection of conductive paste-filled through holes to connect two multilayers. Pre-curing conditions of conductive paste were investigated to find their effects on resistance, bond strength and volume shrinkage. The reliability of pre-curing conductive paste was also analyzed.

Pre-curing conditions led to a great influence on the resistance, bond strength and volume shrinkage of the conductive paste. The best condition of pre-curing conductive paste was chosen as the low curing temperature of 60°C and a curing time of 30 min. Cured conductive paste exhibited square resistance of 4.205 mΩ/□ and bonding strength of 22.86 N. The as-obtained pre-curing condition could improve the reliability of conductive paste. Pre-curing process of conductive paste at extremely low temperature to interconnect two multilayer structures improved the density interconnection of backboard for press-fit applications.

The use of HDI of backboard could lead to good assembly for high-speed signal transmission of electronic products with press-fitting components. The connection of pre-curing conductive paste for multilayers could have important function for improving the application for communication backboard.

Graphene is a two-dimensional material. Its use has many advantages in gas sensing, but its long desorption process is problematic. The aim of this paper is to design a graphene-based gas sensor, study the response to NO₂ gas concentrations and find ways to accelerate the desorption process.

In one group, the sensor was placed in air to measure its initial resistance. Then, it was exposed to the NO₂ gas at a certain concentration. Finally, the sensor was exposed to light immediately after NO₂ gas exposure was ended. In another group, the sensor was heated using a heating plate at a stable temperature, before taking the measurements. Then the adsorption and desorption experiments were carried on.

Illumination and heating at a suitable temperature can expedite desorption of NO₂ molecules on graphene.

In the paper, two main methods are introduced to accelerate the desorption process when the NO₂ gas is absorbed on graphene. Through a series of experiments and analysis, the authors found that the recovery time could be reduced observably and the recovery performance of the graphene-based NO₂ sensor could be improved effectively.

There is a growing literature in nonparametric econometrics in the recent two decades. Given the space limitation, it is impossible to survey all the important recent developments in nonparametric econometrics. Therefore, we choose to limit our focus on the following areas. In Section 2, we review the recent developments of nonparametric estimation and testing of regression functions with mixed discrete and continuous covariates. We discuss nonparametric estimation and testing of econometric models for nonstationary data in Section 3. Section 4 is devoted to surveying the literature of nonparametric instrumental variable (IV) models. We review nonparametric estimation of quantile regression models in Section 5. In Sections 2–5, we also point out some open research problems, which might be useful for graduate students to review the important research papers in this field and to search for their own research interests, particularly dissertation topics for doctoral students. Finally, in Section 6 we highlight some important research areas that are not covered in this paper due to space limitation. We plan to write a separate survey paper to discuss some of the omitted topics.

This paper aims to investigate the increasing trend of multigenerational co-living in the USA and to research the socioeconomic and cultural determinants of such decision.

This study uses the 2017 American Housing Survey data to run descriptive and regression analysis.

The authors find household income appears consistently to be the most significant factor determining multigenerational co-residence decision across all household compositions. Latino households are most likely to co-reside with multiple generations, followed by Asian and African American households. Immigrants tend to live in multigenerational co-residential housing units with smaller sizes and more impoverished neighborhoods, but show greater flexibility in making residential arrangements once they gain better education. In addition, older householders or female householders are significantly more likely to co-reside with multiple generations. Living in metropolitan areas has no impact on co-residence choice, although some evidence suggests that multigenerational co-residential families tend to live in inferior neighborhoods.

This study provides updated evidence on multigenerational co-residence choice in the contemporary United States. The findings provide evidence on how households make residential choices in response to financial hardships and contribute to the theoretical understanding of the variations of such decisions among immigrants and different ethnic and aging groups.

This study on multigenerational co-residence choice imposes important practical implications. The unprecedented COVID-19 pandemic creates ideal research setting to study how households cope with the tremendous uncertainties in the job markets and financial markets. Although multigenerational co-living may work well for some households with lower or moderate-income for financial reasons, it is not an attractive option for every family.

Sharing a home with multiple generations can be challenging. Policymakers should design policies and programs to provide households with guidance on how to live peacefully in multigenerational settings and make multigenerational co-living an appealing and cost-effective housing option for American families of all means.

This study contributes to the existing literature by providing new evidence on the determinants of multigenerational co-residence decision. This study’s findings are fundamental to guide policymakers in carrying out policies and programs aimed at providing a more appealing and cost-effective housing arrangement for American families. The evidence on the senior and minority subsamples are especially meaningful as the vast majority of the baby boom generation in the USA is aging and substantial growth is expected in multigenerational households over the next several decades. Understanding the increasing burden of old-age depression in aging societies will help policymakers prioritize public resources in city planning to address the needs of this rapidly growing population.

Optimized plating conditions, included proper designs of insulating shield (IS), auxiliary cathode (AC) and different patterns, contribute to the uniformity enhancement of copper deposition.

Plating experiments were implemented in vertical continuous plating (VCP) line for manufacturing in different conditions. Multiphysics coupling simulation was brought to investigate and predict the plating uniformity improvement of copper pattern. In addition, the numerical model was based on VCP to approach the practical application.

With disproportionate current distribution, different plating pattern design formed diverse copper thickness distribution (CTD). IS and AC improved plating uniformity of copper pattern because of current redistribution. Moreover, optimized plating condition for effectively depositing more uniformed plating copper layer in varied pattern designs were derived by simulation and verified by plating experiment.

The comparison between experiment and simulation revealed that multiphysics coupling is an efficient, reliable and of course environment-friendly tool to perform research on the uniformity of pattern plating in manufacturing.