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The main purpose of this paper is to understand and model the hydrodynamic influence of surface textures on journal bearings.

In the model, a rectangular array of circle dimples is used to modify the film thickness expression. In full film and cavitation regions, classical Reynolds equation and Reynolds boundary condition are used as the governing equations, respectively. By setting high load bearing capacity as the main optimal goal, the influence of textures on tribological characteristics is studied to get the optimal distribution and parameters of textures.

The results suggest that the load bearing capacity of a journal bearing may be improved through appropriate arrangement of textures partially covering its sleeve. The reduction of the cavitation area may also be achieved by arranging the textures in divergent region. With a high density distribution of textures which have step depths varying linearly along the circumferential direction of the bearing, the load bearing capacity enhancement seems to give good performance. Comparing with smooth bearing, the load bearing capacity enhancement of such textures is about 56.1 per cent, although the influence of texture diameters for the same area density seems insignificant.

The paper shows how surface textures can be designed on journal bearing to improve its tribological performances.

Corporate entrepreneurship is an important way for organizations to gain competitive advantages and achieve sustainable development. However, few studies pay attention to the influence of CEO strategic leadership on corporate entrepreneurship. Drawing on social identity theory and uncertainty-identity theory, this study aims to investigate whether CEO relationship-focused leadership impacts corporate entrepreneurship through middle managers’ (MMs’) organizational identification and whether the indirect effect is moderated by environmental uncertainty.

Using 192 Chinese samples with 192 firm-level and 716 department-level observations, this study uses multilevel structural equations modeling by Mplus 8.0 to test the theoretical model.

This study finds that CEO relationship-focused leadership positively predicts MMs’ organizational identification and corporate entrepreneurship, and MMs’ organizational identification mediates the relationship between CEO relationship-focused leadership and corporate entrepreneurship. In addition, environmental uncertainty moderates not only the relationship between CEO relationship-focused leadership and MMs’ organizational identification but also the indirect effect of CEO relationship-focused leadership on corporate entrepreneurship through MMs’ organizational identification.

This study enriches the understanding of process and contextualization of CEO strategic leadership influencing on corporate entrepreneurship.

To the best of the authors’ knowledge, this study is among the first to explore the influence of CEO relationship-focused leadership on corporate entrepreneurship.

The purpose of this paper is to examine how microblog communication enabled a new form of hybrid net-roots third-sector organization that rely heavily on the internet to achieve multiple organizational successes in civil society, social movement and service providing in China, where the government holds predominating power over the third sector.

A qualitative inductive analysis was conducted to analyze two successful organizations’ Sina tweets sent from their Weibo debuts to the dates when they achieved their first milestone successes. In the analysis, the author iteratively alternated between emic data coding and etic reference to literature on social movement rhetoric and nonprofits’ microblog communication.

This study developed an indigenous communication framework featuring three key communication strategies: changing perceptions, mobilizing action, and building and maintaining relationships, each associated with specific tactics. These strategies and tactics allowed both organizations to tap into social media’s interactive features to engage publics and construct legitimacy.

This paper enriches social media-based communication research and classic social movement rhetoric, and further illustrates strategic communication’s active role in reacting to and reforming institutional contexts. Findings from study might be extended to address similar problems experienced by nonprofits across countries, especially within those that operate in a context where institutional separation from a predominant government is unavailable.

This original communication framework developed in this study crystalizes strategic microblog use by a nascent type of nonprofit when fulfilling functions reflects civil society, social movements and traditional nonprofit organizations in an understudied political and social context.

This chapter uses the entrepreneurial experiences of women entrepreneurs in urban China as an empirical case to discuss contextual influences on women's everyday entrepreneurial experience in developing countries. Based on thematic analysis of women's own accounts of their entrepreneurial experiences, four contextual influences emerged: (1) preentrepreneurial work experience, (2) national entrepreneurial development, (3) cultural values, and (4) gendered work ideology. These influences shaped and were shaped by women's entrepreneurial identities, decisions, and actions in situated contexts. To further understand women's negotiations with these influences in developing countries, future research are called for to investigate how women resist dominant structures to carve out entrepreneurial agencies and enact resiliency to build sustainable businesses.

The purpose of this study is to document how restaurant’s business-to-consumer communication strategies evolved on Facebook over time and how consumers’ reactions to a variety of Facebook messages changed over time.

This study analyzed 2,463 Facebook messages posted by seven quick-service restaurant chains and three casual-dining restaurant chains in the fourth quarter of 2010, 2012 and 2014. ANOVA and post hoc t-test were used to compare the differences among four media types (photo, status update, video and hyperlink) in terms of their usage by companies and Facebook users’ reactions to these messages (measured by number of “Likes”, number of comments and number of shares).

Over the three periods of time under observation, there is a substantial decrease of status updates by restaurants and a dramatic increase of photo updates. Photo remained as the most “popular” media type, receiving most “Likes”, comments and shares from consumers. Video was not considered “popular” in 2010 but experienced a slight increase in usage and slowly emerged in 2012 and 2014 as another “popular” media, which no longer had statistical difference with photo in number of comments and shares.

Some limitations include an under representable sample and its longitudinal design, but the findings provide additional insight to current literature in social media.

A series of suggestions were advanced from the findings to help hospitality managers better engage Facebook users.

This is probably the first time-series or longitudinal-like analysis in social media research and yields meaningful findings.

In this paper, with the goal of reducing the fuel consumption of UAV, the engine performance optimization is studied and on the basis of aircraft/engine integrated control, the minimum fuel consumption optimization method of engine given thrust is proposed. In the case of keeping the given thrust of the engine unchanged, the main fuel flow of the engine without being connected to the afterburner is optimally controlled so as to minimize the fuel consumption.

In this study, the reference model real-time optimization control method is adopted. The engine reference model uses a nonlinear real-time mathematical model of a certain engine component method. The quasi-Newton method is adopted in the optimization algorithm. According to the optimization variable nozzle area, the turbine drop-pressure ratio corresponding to the optimized nozzle area is calculated, which is superimposed with the difference of the drop-pressure ratio of the conventional control plan and output to the conventional nozzle controller of the engine. The nozzle area is controlled by the conventional nozzle controller.

The engine real-time minimum fuel consumption optimization control method studied in this study can significantly reduce the engine fuel consumption rate under a given thrust. At the work point, this is a low-altitude large Mach work point, which is relatively close to the edge of the flight envelope. Before turning on the optimization controller, the fuel consumption is 0.8124 kg/s. After turning on the optimization controller, you can see that the fuel supply has decreased by about 4%. At this time, the speed of the high-pressure rotor is about 94% and the temperature after the turbine can remain stable all the time.

The optimal control method of minimum fuel consumption for the given thrust of UAV is proposed in this paper and the optimal control is carried out for the nozzle area of the engine. At the same time, a method is proposed to indirectly control the nozzle area by changing the turbine pressure ratio. The relevant UAV and its power plant designers and developers may consider the results of this study to reach a feasible solution to reduce the fuel consumption of UAV.

Fuel consumption optimization can save fuel consumption during aircraft cruising, increase the economy of commercial aircraft and improve the combat radius of military aircraft. With the increasingly wide application of UAVs in military and civilian fields, the demand for energy-saving and emission reduction will promote the UAV industry to improve the awareness of environmental protection and reduce the cost of UAV use and operation.

The purpose of the investigation was to research the best process of electroless nickel (EN) plating on AZ91D magnesium alloy and the performance of EN plating coating.

Through single factor test and orthogonal test, EN plating on AZ91D magnesium alloy was researched. The plating rate and porosity were analyzed. The coating appearance of EN plating coating and magnesium alloy substrate was evaluated. The electrochemical properties of EN plating coating and substrate were researched using electrochemical workstation, and their compositions and structure were examined using X-ray diffraction and scanning electron microscopy.

The results made by combination of experimental and orthogonal test showed that the best formula of EN plating was 8.8 g·L⁻¹ nickel ion, 25 g·L⁻¹ lactic acid, 28 g·L⁻¹ reducing agent, 1.8 ml·L⁻¹ corrosion inhibitor, 1 mg·L⁻¹ stabilizer, temperature at 85°C and pH value at 5.5. The plating was uniform, dense and with no cracks. The electrochemical tests showed that the corrosion resistance of EN plating was better than that of magnesium alloy substrate.

The results indicated that the corrosion resistance of magnesium alloy improved markedly after EN plating at the best formula and the plating covered magnesium alloy completely.

This paper aims to examine the optimal sourcing strategies and pricing decisions of competing toy manufacturers and to discuss how manufacturers’ decisions are impacted by competition.

The authors consider a single-period model to characterise the competition between two competing toy manufacturers. Both of them are free to choose between virgin material and recycled material. The authors consider two types of consumers: sensitive consumers who are concerned about product safety and prefer the toy made of virgin material and insensitive consumers who do not care what material is used in the toy. The competing manufacturers play a Cournot competition.

The results reveal a special case of a win-win situation for both the manufacturer and the consumer. In addition, an increasing number of sensitive consumers does not always raise the price of virgin-material toys.

The authors derive the manufacturer’s equilibrium sourcing strategies, corresponding market-clearing prices and profits obtained.

The paper investigates how toy manufacturers’ optimal sourcing strategies are impacted by competition, considering market segments.

As China’s industrial structure continues to upgrade and optimize, the consumption capacity of rural residents gradually improves and the role of consumption in economic growth is increasingly prominent. Against the background of weak external demand, the untapped potential of rural consumption has become a key force in expanding domestic demand. As one of the important means that the government has long relied on, fiscal support for agriculture has played a crucial role in activating the rural consumer market. This manuscript aims to explore the impact of local fiscal support for agricultural expenditure (FSAE) on rural consumption in China, as well as to examine the mediating role of the level of rural financial development.

In this manuscript, the authors use the provincial panel data of 31 provinces in China from 2000 to 2020. The data of all variables mainly come from China Statistical Yearbook and China Rural Statistical Yearbook. According to the variable selection above, 651 sample data of 31 provinces and cities across China from 2000 to 2020 are organized. In terms of methodology, multiple fixed-effects panel model is applied to regression.

Firstly, FSAE varies significantly, while rural consumption slowly but steadily rises, with a relatively stable consumption structure. Secondly, FSAE has a significant positive effect on rural consumption. Thirdly, mediation testing indicates that mechanisms such as income, uncertainty and financial development have significant positive mediating effects on rural consumption. Thirdly, there is evident regional heterogeneity in FSAE’s impact on rural consumption. The Western regions, under government fiscal support, show a more significant effect on the elevation of rural consumption levels, while the role of FSAE in optimizing the consumption structure of rural residents in eastern and central regions is more pronounced.

Firstly, a systematic examination of local FSAE and rural consumption has been conducted, enriching relevant theories. Secondly, utilizing econometric empirical methods to research the relationship between local FSAE and rural consumption provides an exploratory extension to empirical studies on rural consumption in China. This offers empirical evidence for local fiscal support in agricultural development and the promotion of rural consumption.