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Question answering (QA) answers the questions asked by people in the form of natural language. In the QA, due to the subjectivity of users, the questions they query have different expressions, which increases the difficulty of text retrieval. Therefore, the purpose of this paper is to explore new query rewriting method for QA that integrates multiple related questions (RQs) to form an optimal question. Moreover, it is important to generate a new dataset of the original query (OQ) with multiple RQs.

This study collects a new dataset SQuAD_extend by crawling the QA community and uses word-graph to model the collected OQs. Next, Beam search finds the best path to get the best question. To deeply represent the features of the question, pretrained model BERT is used to model sentences.

The experimental results show three outstanding findings. (1) The quality of the answers is better after adding the RQs of the OQs. (2) The word-graph that is used to model the problem and choose the optimal path is conducive to finding the best question. (3) Finally, BERT can deeply characterize the semantics of the exact problem.

The proposed method can use word-graph to construct multiple questions and select the optimal path for rewriting the question, and the quality of answers is better than the baseline. In practice, the research results can help guide users to clarify their query intentions and finally achieve the best answer.

Direct additive manufacturing of ceramics (DAMC) is a highly promising ceramics preparation technology because of its simple process and rapid response capability, but the cracking issue prevents its industrial application. The purpose of this paper is to propose aluminum titanate (Al₂TiO₅) with low coefficient of thermal expansion (CTE) to suppress cracks during the DAMC.

Al₂O₃/Al₂TiO₅ (A/AT) composite ceramic samples with different compositions were in-situ synthesized from Al₂O₃/TiO₂ (A/T) powder in a directed laser deposition (DLD) process. The relationship between the content of TiO₂ and cracking characteristics of fabricated sample was discussed. Phase composition, microstructure and properties of the fabricated samples were also investigated.

The results of this paper show that the doping of TiO₂ can obtain Al₂TiO₅ synthesized in situ by reaction with Al₂O₃ and effectively suppress cracks during DAMC. When the content of TiO₂ reaches 30 wt.per cent, cracks hardly occur even under conditions of slow deposition. Crack-free structures such as vane, cone and pyramid were successfully prepared, with a maximum cross-sectional dimension of 30 mm and maximum length of 150 mm. A continuous matrix phase formed of the low CTE of Al₂TiO₅ is the major cause of crack suppression. The dispersed distribution of a-Al₂O₃ columnar dendrites has the effect of increasing the strength of the matrix. Under current process conditions, the prepared sample with 10 wt.per cent TiO₂ has micro-hardness of 21.05 GPa and flexural strength of 170 MPa.

This paper provides a new method and inspiration for direct additive manufacturing of large-sized crack-free ceramics, which has the potential to promote practical application of the technology.

Despite the dramatic increase in people's use of social media, relatively few studies have examined its effect on careers. Drawing upon social comparison theory and self-regulation theory, this study aims to investigate how career-oriented social media usage interacts with social comparison orientation (SCO) to influence the career exploration of university students.

Three waves of survey data are collected from 482 university students in China. Hypotheses are tested through ordinary least squares analysis.

Results show that career-oriented social media usage increases career anxiety, which in turn promotes career exploration. Furthermore, SCO strengthens such influence of career-oriented social media usage.

Given the limited attention paid to the effects of social media in career contexts, this study distinguishes career-oriented social media usage and proposes insights into its effect on career exploration. In doing so, this study extends social media literature and provides implications for the transition of university students from school to work in the digital era.

This research aims to provide a theoretical method and data supports for a future study on interfacial reaction mechanism and spreading mechanism between molten solder and V-shaped substrate, which also gives guidance for those complicated welding operation objects in brazing technique.

Wetting experiments were performed to measure the contact angles at different temperatures of molten Sn-3.0Ag-0.5Cu wetting on the quartz substrate with an included angle of 90°. According to the experimental results, the theoretical spreading morphology of molten solder on V-shaped substrate at corresponding temperature was simulated by Surface Evolver.

The theoretical morphology profiles of the molten solder sitting on the V-shaped substrate are simulated using Surface Evolver when the molten solder reaches spreading equilibrium. The spreading mechanisms as well as the impact of surface tension and gravity on interfacial energy of the molten solder wetting on the V-shaped groove substrate are also discussed where theoretical results agree well with experiment results. The contact area between the gas and liquid phases shows a tendency of first increasing and later decreasing. Otherwise, the spreading distance and the height of the molten solder increases as the droplet volume increases as the included angle and the contact angle are given as constants, and both the interfacial energy and the gravitational energy increase as well. This research has a wide influence on predicting the outcomes in commercial impact and also gives guidance for those complicated welding operation objects in brazing technique.

It is of very important significance in both science and practice to investigate the differences between the flat surface and V-shaped surface. Some necessary parameters including intrinsic contact angle and surface tension need to be directly measured when the droplet spreads on the flat surface. The relevant simulation conclusions on the inherent characteristics can be given based on these intrinsic parameters. Compared with the flat surface, the V-shaped substrate is chosen for further discuss on the effects of gravity on the droplet spreading behavior and the changes of apparent contact angle which can only occurs as the substrate is inclined. Therefore, this research provides theoretical method and data supports for a future study on interfacial reaction mechanism and spreading mechanism between molten solder and substrate.

The research is developed for verifying the accuracy of the model built in Surface Evolver. Based on this verified model, other researches on the spreading distance along y-axis and the contact area that are especially difficult to be experimentally measured can be directly simulated by Surface Evolver, which can provides a convenient method to discuss the changes of horizontal spreading distance, droplet height and contact area with increasing the included angle of V-shaped substrate or with increasing the droplet volume. Actually, the modeling results are calculated for supplying the theoretical parameters and technical guidance in the welding process.

This research provides theoretical method and data supports for a future study on interfacial reaction mechanism and spreading mechanism between molten solder and substrate, which has a wide influence on prediction the outcomes in commercial impact and also gives guidance for those complicated welding operation objects in brazing technique.

Surface Evolver, can also be used to discuss the structure and spreading mechanism of droplets on V-shaped substrates, which have not been discussed before.

The purpose of this paper is to examine the financing and provision of basic public services in China. The main issue addressed is how to reform the public finance system to achieve quality and fairness in the provision of basic public services.

Based on an historical analysis of the functional transformation of the public finance system in China and on an empirical analysis of the current public finance system and the public service provision system, a comprehensive understanding was gained about the relationship between the financing and provision of basic public services.

The paper argues that there is a close relationship between the provision of basic public services and the functional changes made to the public finance system. Based on a systematic retrospective study of the Chinese Government’s efforts to improve basic public services over the last three decades, this paper offers policy suggestions on further public finance restructuring that would support better service provision.

By analyzing issues in the public service provision system, this paper contributes to the debate about the efficiency improvement made to governmental functions in China.

The authors investigate how a gender-diverse board, a gender-diverse executive team, or a female chief executive officer (CEO) impact bank balance sheet and equity risk.

Using panel data of U.S. bank holding companies over the period of 1992–2019, the authors conduct panel regressions with bank and year-fixed effects to analyze how female directors, female executives, and female CEOs impact a wide range of bank risk measures, controlling for the bank, board and executive characteristics.

The authors find female directors significantly reduce all types of risk. Female executives reduce some balance sheet risk but have an insignificant effect on bank equity risk. However, the presence of female CEOs does not significantly reduce bank risk-taking. During financial crises, female CEOs even increase equity risk.

The findings are important to shed light on the ongoing debate on how gender quota policy could be efficiently used to balance the need for gender diversity while ensuring corporate performance. It could also improve social welfare by guiding proper public policy to ensure the efficient use of social labor capital and curb banks' excessive risk-taking incentives.

The authors provide the first empirical evidence demonstrating that female directors and female executives in the banking industry have different impacts on bank risk-taking. The authors also provide the first empirical evidence that female leaders have a different impact on two different types of risks: balance sheet and equity risk. The study is also the first to analyze the impact of female executives over multiple financial crises.

Visual object tracking plays a significant role in intelligent robot systems. This study aims to focus on unlocking the tracking performance potential of the deep network and presenting a dynamic template update strategy for the Siamese trackers.

This paper presents a novel and efficient Siamese architecture for visual object tracking which introduces densely connected convolutional layers and a dynamic template update strategy into Siamese tracker.

The most advanced performance can be achieved by introducing densely connected convolutional neural networks that have not yet been applied to the tracking task into SiamRPN. By using the proposed architecture, the experimental results demonstrate that the performance of the proposed tracker is 5.8% (area under curve), 5.4% expected average overlap (EAO) and 3.5% (EAO) higher than the baseline on the OTB100, VOT2016 and VOT2018 data sets and achieves an excellent EAO score of 0.292 on the VOT2019 data set.

This study explores a deeper backbone network with each convolutional network layer densely connected. In response to tracking errors caused by templates that are not updated, this study proposes a dynamic template update strategy.

The paper aims to establish a quality assurance framework for Chinese private higher education (PHE) in particular and for any newly-established higher education sector in general.

This research relied on published qualitative and quantitative data, existing literature, historical documents, and the authors' observations. It described the PHE growth context, analyzed the quality issue from three dimensions (academic, administrative, and relationship quality), and examined its quality assurance practice through three players.

The paper provides empirical insights about how quality and quality assurance issues have impacted on PHE development. To approach the issues, it suggests a “quality assurance triangle” framework that is composed of three PHE players (government, market, institution) and their joint association.

Because of the relative position of each player in current quality assurance, the success of its implementation in China depends on how the government establishes the triangle system and balances its dominating roles to ensure each of the players act independently and collaboratively.

This framework provides directions for establishing an appropriate quality assurance system for PHE in China.

This paper fulfills an identified need to setup a sound quality assurance system for PHE in China and contributes to quality assurance literature with a new framework.

There are mainly two viewpoints on women’s leadership effectiveness compared with that of men – the questioning view and the admiring view, two points of view that are not in agreement. Based on that, this study aims to find the gender difference in leadership effectiveness.

This study uses carefully matched male and female presidents (223 pairs) of Chinese listed companies and male and female chief executive officers (141 pairs) of American listed companies as samples. Analysis of variance was conducted to analyze the indicator data of the leadership effectiveness.

The findings show that women’s leadership effectiveness is not significantly inferior to that of men, and that women’s leadership effectiveness compared to that of men in the Chinese cultural context is not inferior to that in the American cultural context. The findings do not support the questioning view of women’s leadership effectiveness.

This study first uses the carefully matched (female/male leaders) data of Chinese listed companies and American listed companies as samples to find which viewpoint (the questioning view and the admiring view) is supported or is not supported.

The purpose of this paper is to present a new human dynamics model to explain the process of verified users' (VUs) posting on Sina micro-blog.

A common human dynamics research method with three steps is applied. Firstly, a large-scale behavioral dataset is collected involving 495 VUs and five topics on Sina micro-blog. Second, five important indicators that reveal the characteristics of posting behavior are analyzed. Then, a quantitative model is constructed to describe the process of posting behavior, and its validity is verified by simulations.

Three important characteristics of VUs' micro-blog posting behavior are observed: fat-tailed distribution, fluctuation and periodicity. These characteristics do not fit the assumption of interest-driven models proposed by previous literature. An optimized task-driven model is introduced to describe this complex phenomenon mathematically. The model is verified on empirical data, confirming that task-driven models can be optimized to explore information behavior on social media.

Being different from previous studies that mainly describe common users' posting behavior on social media by applying interest-driven models, this paper customizes an optimized task-driven model for VUs, who mainly treat social media as a platform for work and play a crucial role in information creation on social media.