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This paper aims to systematically investigate the effect of the heat treatment process parameters on the microstructure and mechanical properties of the selective laser melting (SLM) AlSi10Mg alloy.

The samples with very low porosity were fabricated with optimized processing parameters on a self-developed SLM system. The heat treatment of using the temperature of 170°C∼400°C and the holding time of 0.5∼12 h was studied, and the evolution of the microstructure and mechanical properties of AlSi10Mg alloy under direct aging and annealing was investigated and obtained.

After annealing above 300°C for 1 h, the dendrite Si in the sample occurs spheroidization, and the molten pool contour becomes blurred or even disappeared completely, but low-temperature heat treatment does not change the morphology and size of grains significantly. Except for holding at 200°C for 1 h, all other heat treatment processes cause the tensile and yield strengths of SLM AlSi10Mg alloys to decrease and the elongation to increase. When the annealing temperature is higher than 200°C, the higher the temperature and the longer the holding time, the more obvious this effect is.

The correlation between the mechanical properties and microstructure of SLM AlSi10Mg alloy under different conditions was obtained. According to the characteristics of SLM forming, the direct aging and annealing process are mainly studied, which provided new information for the heat treatment of SLM AlSi10Mg alloy and promoted the engineering application of SLM AlSi10Mg alloy.

The purpose of this paper is to discover an effective maize price for trading and policy-making reference by assessing the price transmission of the US spot and futures maize prices to Chinese counterparts.

The authors apply a systematic, quantitative method to analyze the integration between US and Chinese maize markets. Based on the residuals of the variables through error correction model, the directed acyclic graph (DAG) among six price variables is conducted. With consideration of the dependence on and direction of six price variables, the variance decomposition of each variable is calculated.

This paper shows that the vertical price transmission passes from wholesale price to farm-gate price. The horizontal price transmission ranges from spot price to futures price at the domestic market and from the American spot price to domestic spot price, from the American spot price to domestic futures price and from the American futures price to domestic futures price. The American maize spot and futures prices, and in particular the spot price, have greater effects on domestic maize prices contemporaneously. It also indicates that the American spot price is the leader price in the long run at both maize markets.

This paper contributes by using the DAG method in this paper. It also contributes by helping policy makers and market participants find the leading prices and offers insight into ways of gaining power of price setting in the maize market.

The purpose of this paper is to measure a single financial institution's contribution to systemic risk by using extremal quantile regression and analyzing the influential factors of systemic risk.

Extreme value theory is applied when measuring the systemic risk of financial institutions. Extremal quantile regression, where extreme value distribution is assumed for the tail, is used to measure the extreme risk and analyze the changes in and dependencies of risk. Furthermore, influential factors of systemic risk are analyzed using panel regression.

The key findings of the paper are that value at risk and contribution to systemic risk are very different when measuring the risk of a financial institution; banks’ contributions to systemic risk are much higher; and size and leverage ratio are two significant and important factors influencing an institution's systemic risk.

Characterizing variables of financial institutions such as size, leverage ratio and market beta should be considered together when regulating and constraining financial institutions.

To take extreme risk into account, this paper measures systemic financial risk using extremal quantile regression for the first time.

The purpose of this paper is to discuss the autonomous navigation and guidance scheme for future precise and safe planetary landing.

Autonomous navigation and guidance schemes are proposed based on inertial measurement unit (IMU) and optical navigation sensors for precise and safe landing of spacecrafts on the moon and planetary bodies. First, vision‐aided inertial navigation scheme is suggested to achieve precise relative navigation; second, two autonomous obstacle detection algorithms, based on grey image from optical navigation camera and digital elevation map form light detection and ranging sensor, respectively, are proposed; and third, flowchart of automatic obstacle avoidance maneuver is also given out.

This paper finds that the performance of the proposed scheme precedes the traditional planetary landing navigation and guidance mode based on IMU and deep space network.

The presented schemes need to be further validated by the mathematical simulations and hardware‐in‐loop simulations, and then they can be used in the real flight missions.

The presented schemes are applicable to both future planetary pin‐point landing missions and sample return missions with little modification.

This paper presents the new autonomous navigation and guidance scheme in order to achieve the precise and safe planetary landing.

The purpose of this paper is to explore the correlations among entrepreneurial environment, market-oriented strategies, and entrepreneurial performance.

Entrepreneurial environment is measured by institutional environment and industrial environment. A survey of 176 large Chinese automobile firms is conducted. The structural equation model is applied to perform analysis.

The uncertainty of the institutional environment is positively related with market-oriented strategies and market-oriented strategies are positively related with firms’ performance. The stronger the uncertainty of the industrial environment is, the larger impact that market-oriented strategies have on firms’ performance will be. There is no distinct positive relationship between the uncertainty of industrial environment and firms’ market-oriented strategies. The hypothesis, that the stronger the uncertainty of institutional environments is, the larger the impact that market-oriented strategies will be on firms’ performance, is not supported.

In terms of research design, this paper does not select survey samples randomly. This paper only takes institutional and industrial environments into consideration while the environmental characteristics are omitted.

This paper expands entrepreneurship research by integrating previous studies. Findings in this paper are helpful for firms in emerging countries to implement “going abroad strategies,” to start up new businesses in other countries, and to achieve the goals of improving competitiveness and integrating with international firms.

Research on new internet venture growth is lacking. The purpose of this paper is to address the gap by developing and testing a theoretical model that links venturing principles (effectuation or causation) to new internet venture growth through resource bundling (pioneering or stabilizing).

The proposed theoretical model is developed upon the entrepreneurship literature and resource-based view. Empirical data are collected from entrepreneurs and top executives in China via a survey. The Baron and Kenny (1986) mediation model assessment procedure is used to analyze the data.

Both effectuation and causation are positively associated with new internet venture growth. Effectuation leads to pioneering resource bundling, which in turn contributes to new internet venture growth. Causation also contributes to new internet venture growth, but through stabilizing resource bundling.

This research helps link the theory of effectuation to resource-based theory by revealing resource bundling as the mediator between effectuation, causation, and new venture growth. Moreover, the authors provide empirical evidence of the importance of resource bundling with entrepreneurial strategic decision logics to the growth of new internet ventures in transitional economies.

Entrepreneurs and managers of new internet ventures should leverage both venturing principles to support growth. Internet ventures generally are creative and innovative in nature, hence favor effectuation. But it will be unwise to ignore causation, which also leads to growth.

This is an original empirical research guided by theories. It is a novel insight to identify the mediating effect of resource bundling. This study likely will inspire more scholarly research on the subject. It also lays a solid foundation for further inquiry such as complementarities between effectuation and causation.

Cause-related marketing (CRM) is an increasing popular marketing strategy in which a firm donates a specific amount to a designed cause when customers engage in revenue-providing exchanges. Based on balance and attribution theory, this paper aims to explore the interaction effect of donation amount and ad orientation, two important factors of formulation and communication of CRM, respectively, on consumer response and the mediating effect of consumers’ perceived company motives.

Two 2 (donation amount: small vs large) × 2 (ad orientation: product- vs cause-oriented) between-subjects experimental studies were conducted in marketing course with 284 and 157 Chinese undergraduate students participating in Studies 1 and 2, respectively. ANOVA and regression were used to test the hypotheses.

Study 1 shows the significant interaction effects of donation amount and ad orientation on consumers’ response. When CRM has a large donation amount, cause-oriented (vs product-oriented) ad leads to consumers’ more positive company attitude and higher purchase intention. The opposite is true for the small donation amount condition. Study 2 shows that the above interaction effect is mediated by consumer-attributed company motives. The attributed motive of sincerely caring about social cause has significant positive effect on consumer response, whereas the attributed motive of increasing sales or improving corporate image does not.

This paper contributes to the literature by empirically examining the interaction effect of donation amount and ad orientation on consumer-inferred motives and behavioral response. The findings are valuable because they indicate the importance of matching between factors at formulation and communication stage. In addition, this paper found that consumers are “tolerant” of companies using CRM to promote product sales and improve brand image.

This study aims to identify the prominent topics, the distribution and association characteristics of topics and the topic evolutionary trends of Documentary Heritage Preservation and Conservation (DHPAC) research in China.

Keywords of relevant papers in China National Knowledge Infrastructure (CNKI) were extracted as the data source in this study. First, frequency and co-occurrence of keywords of the selected papers were obtained by using SATI. Second, co-word network indicators were calculated with the Pajek software. Then, VOSviewer was applied to optimize the visualization of the sub-communities. Finally, a topics evolution map of this research field was implemented by CorTexT.

The research topics of DHPAC research in China were unbalanced but distinct. Topics of DHPAC research in China possessed inconspicuous orientation and consistency. The core topics had less influence on the overall network. A research system had formed with archival conservation and ancient books conservation as the core research directions. Research in this field had formed four continuous evolutionary paths about ancient books conservation, salvage conservation, archival conservation and archives conservation technology science with topics fusion and differentiation coexisting. Attentions on “ancient books conservation”, “paper relics conservation”, “electronic record”, “digitization”, “minority”, “documents in the republic of China” had increased during the past two decades and new hot topics of DHPAC research kept appearing in China.

This study synthesized and analyzed the research results of DHPAC research in China from a more comprehensive perspective and revealed the topic structure and longitudinal evolution process intuitively with co-word analysis and social network analysis, which can assist researchers to improve research systematization, discover new research directions and seek cooperative research path.

The purpose of this paper is to investigate the relationships between academic self-efficacy, study engagement and perceived lecturer support within a higher education setup.

A convenience sample of 376 respondents from a technical university in Ghana took part in the study by completing self-reported questionnaire. Data were analysed using descriptive statistics and partial least square-based structural equation modelling (PLS-SEM).

Findings suggest academic self-efficacy and perceived lecturer support are positive and significant predictors of study engagement. In addition, perceived lecturer support was a significant moderator between academic self-efficacy and study engagement.

This paper is one of the first to have tested a model including academic self-efficacy, study engagement and perceived lecturer support in a technical university setup from a developing country perspective.

This paper aims to study the oxidation kinetics of the nanocrystalline Al ultrathin films. The influence of structure and composition evolution during thermal oxidation will be observed. The reason for the change in the oxidation activation energy on increasing the oxidation temperature will be discussed.

Al thin films are deposited on the silicon wafers as substrates by vacuumed thermal evaporation under the base pressure of 2 × 10⁻⁴ Pa, where the substrates are not heated. A crystalline quartz sensor is used to monitor the film thickness. The film thickness varies in the range from 30 to 100 nm. To keep the silicon substrate from oxidation during thermal oxidation of the Al film, a 50-nm gold film was deposited on the back side of silicon substrate. Isothermal oxidation studies of the Al film were carried out in air to assess the oxidation kinetics at 400-600°C.

The activation energy is positive and low for the low temperature oxidation, but it becomes apparently negative at higher temperatures. The oxide grains are nano-sized, and γ-Al₂O₃ crystals are formed at above 500°C. In light of the model by Davies, the grain boundary diffusion is believed to be the reason for the logarithmic oxidation rate rule. The negative activation energy at higher temperatures is apparent, which comes from the decline of diffusion paths due to the formation of the γ-Al₂O₃ crystals.

It is found that the oxidation kinetics of nanocrystalline Al thin films in air at 400-600°C follows the logarithmic law, and this logarithmic oxidation rate law is related to the grain boundary diffusion. The negative activation energies in the higher temperature range can be attributed to the formation of γ-Al₂O₃ crystal.