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Laser powder bed fusion (LPBF) in-situ alloying is a recently developed technology that provides a facile approach to optimizing the microstructural and compositional characteristics of the components for high performance goals. However, the complex mass and heat transfer behavior of the molten pool results in an inhomogeneous composition distribution within the samples fabricated by LPBF in-situ alloying. The study aims to investigate the heat and mass transfer behavior of an in-situ alloyed molten pool by developing a three-dimensional transient thermal-flow model that couples the metallurgical behavior of the alloy, thereby revealing the formation mechanism of composition inhomogeneity.

A multispecies multiphase computational fluid dynamic model was developed with thermodynamic factors derived from the phase diagram of the selected alloy system. The characteristics of the Al/Cu powder bed in-situ alloying process were investigated as a benchmark. The metallurgical behaviors including powder melting, thermal-flow, element transfer and solidification were investigated.

The Peclet number indicates that the mass transfer in the molten pool is dominated by convection. The large variation in material properties and temperature results in the presence of partially melted Cu-powder and pre-solidified particles in the molten pool, which further hinder the convection mixing. The study of simulation and experiment indicates that optimizing the laser energy input is beneficial for element homogenization. The effective time and driving force of the convection stirring can be improved by increasing the volume energy density.

This study provides an in-depth understanding of the formation mechanism of composition inhomogeneity in alloy fabricated by LPBF in-situ alloying.

This paper aims to use the Monodepth method to improve the prediction speed of identifying the obstacles and proposes a Probability Dueling DQN algorithm to optimize the path of the agent, which can reach the destination more quickly than the Dueling DQN algorithm. Then the path planning algorithm based on Probability Dueling DQN is combined with FastSLAM to accomplish the autonomous navigation and map the environment.

This paper proposes an active simultaneous localization and mapping (SLAM) framework for autonomous navigation under an indoor environment with static and dynamic obstacles. It integrates a path planning algorithm with visual SLAM to decrease navigation uncertainty and build an environment map.

The result shows that the proposed method offers good performance over existing Dueling DQN for navigation uncertainty under the indoor environment with different numbers and shapes of the static and dynamic obstacles in the real world field.

This paper proposes a novel active SLAM framework composed of Probability Dueling DQN that is the improved path planning algorithm based on Dueling DQN and FastSLAM. This framework is used with the Monodepth depth image prediction method with faster prediction speed to realize autonomous navigation in the indoor environment with different numbers and shapes of the static and dynamic obstacles.

Drawing upon the theory of information culture from information science and prior research on Chinese information practices. The purpose of this paper is to posit that instead of over-relying on Hofstede’s national cultural values, the IS field should develop theories on national information culture to bridge the theoretical gaps found in explaining the differences in individuals’ IT perceptions and behaviors across cultures.

To achieve the objectives of this study, two quantitative studies were conducted. The first study is exploratory in nature and focuses on the development and calibration of an instrument to measure the Chinese information culture (CIC). The second study takes a confirmatory approach to investigate the impact of the CIC on IT perceptions of manager.

The study develops and validates an instrument for measuring the CIC that comprises information source and format preference, information ownership and analysis style, and centralized decision-making and information control. The CIC is found to influence IT perceptions of managers including perceived performance improvement resulted from IT use, attitude toward using work technologies and attitude on the value of IT in general.

This study is one of the first studies to theorize national information culture to understand IT perceptions at the individual level. The development of the CIC measure provides the much needed methodological support for contextualizing cross-cultural research.

By comparing regression models, this study aims to analyze the added home value of green sustainability features and green efficiency characteristics, rather than green certifications, in the city of Austin.

The adoption of home green energy efficiency upgrades has emerged as a new trend in the real estate industry, offering several benefits to builders and home buyers. These include tax reductions, health improvements and energy savings. Previous studies have shown that energy-certified single-family homes command a premium in the marketplace. However, the literature is limited in its analysis of the effects of green upgrades and certification on different types of single-family homes. To address this gap, this research collected data from 21,292 multiple listing services (MLS) closed home-selling listings in Austin, Texas, over a period of 35 months.

The analysis results showed that green efficiency features could generally increase single-family housing prices by 11.9%, whereas green sustainability upgrades can potentially bring a 11.7% higher selling price. Although green housing certification did not have significant effects on most housing groups, it did increase closing prices by 13.2% for single-family residences sold at the medium price range, which is higher than the impacts from simply listing the green features on MLS.

The study contributes to the body of knowledge by examining the market value of broadly defined energy efficiency and sustainability features in the residential housing market. The findings can help policymakers, brokerage firms, home builders and owners adjust their policies and strategies related to single-family home sales and mortgage approvals. The research also highlights the potential benefits of capitalizing on green housing features other than certifications.

The purpose of this paper is to propose a DC-port voltage balance strategy realizing it by logic combination modulation (LCM). This voltage balance strategy is brief and high efficient, which can be used in many power electronic devices adopting the cascaded H-bridge rectifier (CHBR) such as power electronic transformer (PET).

The CHBR is typically as a core component in the power electronic devices to implement the voltage or current conversion. The modulation method presented here is aiming to solve the voltage imbalance problem occurred in the CHBR with more stable work station and higher reliability in ordinary operating conditions. In particular, by changing the switch states smoothly and quickly, the DC-port voltage can be controlled as the ideal value even one of the modules in CHBR is facing the load-removed problem.

By using the voltage balance strategy of LCM, the problem of voltage imbalance occurring in three-phase cascaded rectifiers has been solved properly. With the lower modulation depth, the efficiency of the strategy is shown to be better and stronger. The strategy can work reliably and quickly no matter facing the problem as load-removed change or the ordinary operating conditions.

The limitation of the proposed DC-port voltage balance strategy is calculated and proved, in a three-module CHBR, the LCM could balance the DC-port voltage while one module facing the load-removed situation under 0.83 modulation depth.

This paper provides a useful and particular voltage balance strategy which can be used in the topology of three-phase cascaded rectifier. The value of the strategy is that a brief and reliable voltage balance method in the power electronic devices can be achieved. What is more, facing the problem, such as load-removed, in outport, the strategy can response quickly with no switch jump and switch frequency rising.

The objectives of this study are threefold: to delineate the phenomenon of “You Share, We Donate” (YSWD) campaigns and what distinguishes them from sales-based cause-related marketing; to contrast the effectiveness of YSWD and sales-based cause-related marketing campaigns and provide an explanation for the differences in the effectiveness; to explore boundary conditions of the proposed differences.

Three experiments were conducted to empirically test the differential effect of campaign formats (i.e. YSWD vs sales-based cause-related marketing), the underlying mechanism and structural as well as contextual features moderating the differential effect.

The findings suggest that YSWD messages elicit consumers’ message-sharing intentions more than traditional cause-related marketing messages. The effect is explained by consumers’ sense of empowerment and can be enhanced through donation cap non-specification. The findings further indicate that YSWD campaigns are especially fruitful in low power distance cultures.

This study contributes toward corporate donation campaign literature by focusing on the usage of social media.

From a managerial perspective, this research provides marketers with guidelines on how to choose between the two cause-related marketing campaign formats and how to enhance the effectiveness of YSWD campaigns.

This paper extends cause-related marketing literature by not only introducing the phenomenon of YSWD campaigns to the literature but also exploring strategies to enhance the effectiveness of such campaigns and shedding light on an outcome beyond the sales impact of cause-related marketing campaigns, i.e. an increase of visibility in social media. From a managerial perspective, this research provides marketers with guidelines on how to choose between the two cause-related marketing campaign formats and how to enhance the effectiveness of YSWD campaigns.

Feature selection is crucial for machine learning to recognize lane-change (LC) maneuver as there exist a large number of feature candidates. Blindly using feature could take up large storage and excessive computation time, while insufficient feature selection would cause poor performance. Selecting high contributive features to classify LC and lane-keep behavior is effective for maneuver recognition. This paper aims to propose a feature selection method from a statistical view based on an analysis from naturalistic driving data.

In total, 1,375 LC cases are analyzed. To comprehensively select features, the authors extract the feature candidates from both time and frequency domains with various LC scenarios segmented by an occupancy schedule grid. Then the effect size (Cohen’s d) and p-value of every feature are computed to assess their contribution for each scenario.

It has been found that the common lateral features, e.g. yaw rate, lateral acceleration and time-to-lane crossing, are not strong features for recognition of LC maneuver as empirical knowledge. Finally, cross-validation tests are conducted to evaluate model performance using metrics of receiver operating characteristic. Experimental results show that the selected features can achieve better recognition performance than using all the features without purification.

In this paper, the authors investigate the contributions of each feature from the perspective of statistics based on big naturalistic driving data. The aim is to comprehensively figure out different types of features in LC maneuvers and select the most contributive features over various LC scenarios.

Stainless-clad bimetallic steels (SCBS) are widely investigated in some extremely environmental applications areas, such as polar sailing area and tropical oil and gas platforms areas, because of their excellent anticorrosion performance and relatively lower production costs. However, the properties of SCBS, including the mechanical strength, weldability and the anticorrosion behavior, have a direct relation with the manufacturing process and can affect their practical applications. This paper aims to review the application and the properties requirements of SCBS in marine environments to promote the application of this new material in more fields.

In this paper, the manufacturing process, welding and corrosion-resistant properties of SCBS were introduced systematically by reviewing the related literatures, and some results of the authors’ research group were also introduced briefly.

Different preparation methods, such as rolling composite, casting rolling composite, explosive composite, laser cladding and plasma arc cladding, as well as the process parameters, including the vacuum degree, rolling temperature, rolling reduction ratio, volume ratios of liquid to solid, explosive ratio and the heat treatment, influenced a lot on the properties of the SCBS through changing the interface microstructures. Otherwise, the variations in rolling temperature, pass, reduction and the grain size of clad steel also brought the dissimilarities of the mechanical properties, microhardness, bonding strength and toughness. Another two new processes, clad teeming method and interlayer explosive welding, deserve more attention because of their excellent microstructure control ability. The superior corrosion resistance of SCBS can alleviate the corrosion problem in the marine environment and prolong the service life of the equipment, but the phenomenon of galvanic corrosion should be noted as much as possible. The high dilution rate, welding process specifications and heat treatment can weaken the intergranular corrosion resistance in the weld area.

This paper summarizes the application of SCBS in marine environments and provides an overview and reference for the research of stainless-clad bimetallic steel.

Regular cable trench inspection is crucial, and robotics automation provides an efficient and safer alternative to manual labor. However, existing robots have limited capabilities in traversing obstacles and lack a mechanical arm for detecting cables and equipment. This study aims to develop an intelligent robot for cable trench inspection, enhancing obstacle-crossing abilities and incorporating a mechanical arm for inspection tasks.

This study presents an intelligent robot for cable trench inspection, featuring a six-degree-of-freedom mechanical arm mounted on a six-track chassis with four flippers. The robot's climbing and obstacle-crossing stability, as well as the motion range of the mechanical arm, are analyzed. The positioning, navigation and remote monitoring systems are developed. Experiments, including climbing and obstacle-crossing performance tests, along with navigation and positioning system tests, are conducted. Finally, the robot's practicability is verified through field testing.

Equipped with flipper tracks, the cable trench inspection robot can traverse obstacles up to 30 cm high and maintain stable locomotion on 30° slopes. Its navigation system enables autonomous operation, while the mechanical arm performs cable current detection tasks. The remote monitoring system provides comprehensive control of the robot and environmental parameter monitoring in cable trenches.

The front and rear flipper tracks enhance the robot's ability to traverse obstacles in cable trenches. The mechanical arm addresses cable current and equipment contact detection issues. The navigation and remote monitoring systems improve the robot's autonomous operation and environmental monitoring capabilities. Implementing this robot can advance the automation and intelligence of cable trench inspections.

The purpose of this study is to explore the role of social media usage among business-to-business sales professionals in China. Specifically, the authors seek to define and explore the unique ways in which Chinese salespeople use social media, with a special emphasis on the role of guanxi. Guanxi is a complex cultural construct that revolves around the exchange of favors to build trust and connection for business purposes.

Three in-depth interviews of sales managers from two industries along with survey data from 42 pharmaceutical sales representatives were collected to gain an understanding of the general usage and attitudes toward social media in the sales process in China.

Results indicated that virtually all the salespeople in the sample were highly familiar with social media and integrated it into the sales process. Furthermore, all participants indicated that their companies were highly supportive of the use of social media with their customers. More importantly, salespeople in China view social media as a critical tool in building guanxi with their customers. Findings from this exploratory study are used to create a conceptual framework for understanding the important role of social media in building guanxi in China.

While the sample is limited to three managerial interviews and 42 survey responses, the data indicated a near universal acceptance and use of social media among Chinese salespeople. Most importantly, social media appears to be the modern gateway to the ancient and culturally unique construct of guanxi that is absolutely indispensable to successful business-to-business sales performance in China.

The structural challenges within China make trust and emotional connection essential to any potential business relationship. Trust is at the core of guanxi. Any firm hoping to succeed in China must understand guanxi and the use of Chinese social media to help build it. This study adds to the knowledge and understanding of guanxi and begins to elucidate the uses of social media as a tool to build and maintain it.

Social media appears to be the modern gateway to the ancient and culturally unique construct of guanxi that is absolutely indispensable to successful business-to-business sales performance in China. This study deepens our understanding of not only guanxi but also how the modern phenomenon of social media is affecting it.

This is one of very few studies to investigate the use of social media among salesforces in China. More importantly, the authors know of no other study linking social media with guanxi.