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The purpose of this study is to investigate the tribological performance of helical gear pairs with consideration of the properties of non-Newtonian lubricant and the real three-dimensional (3D) topography of tooth flanks.

Based on the mixed elastohydrodynamic lubrication (EHL) theory for infinite line contact, this paper proposes a complete model for involute helical gear pairs considering the real 3D topography of tooth flanks and the properties of non-Newtonian lubricant. Film thickness, contact load and contact area ratios at the mid-point of contact line are studied for each angular displacement of pinion. Both the total friction coefficient and surface flash temperature are calculated after obtaining the values of pressure and subsurface stress. Then, the influences of input parameters including rotational speed and power are investigated.

During the meshing process, contact load ratio and area ratio of the two rough surface cases first increase and then decrease; the maximum flash temperature rise (MFTR) on the gear is lower than that on the pinion first, but later the situation converses. For cylindrical gears, on the plane of action, there is a point or a line where the instantaneous friction reduces to a minimum value in a sudden, as the sliding–rolling ratio becomes zero. When rotational speed increases, film thickness becomes larger, and meanwhile, contact load ratio, coefficient of friction and MFTR gradually reduce.

A comprehensive analysis is conducted and a computer program is developed for meshing geometry, kinematics, tooth contact, mixed EHL characteristics, friction, FTR and subsurface stress of involute helical gear pairs. Besides, a numerical simulation model is developed, which can be used to analyze mixed lubrication with 3D machined roughness under a wide range of operating conditions.

Urban spatial form influences the social, economic, and ecological development modes of the city. The spatial form during the urbanization of Hanjiang River Basin in Southern Shaanxi needs to be studied. In this study, research methodologies on urban spatial form in China and abroad were summarized. The concept of ecology background was applied, and the research framework for urban spatial form, which integrated the background, framework, core, axis, cluster, and skin, was established. Valley cities in the Hanjiang River Basin in Southern Shaanxi were classified into wide valley, narrow valley, and canyon cities. The spatial form characteristics of these three types of valley cities were discussed. A case study based on a typical city-Yang County-was conducted to discuss the characteristics of the aforementioned six elements of urban spatial form. Finally, spatial form characteristics were summarized. These characteristics provide a basis for the study of the small valley urban spatial form in the Hanjiang River Basin in Southern Shaanxi.

This study aims to examine how young consumers perceive the advertising effectiveness of endorsements by virtual idols and how endorsements by virtual idols differ from endorsements by real human celebrities such as traditional celebrities and online influencers.

An experimental study was conducted with 400 randomly selected young respondents in China in December 2022. A 3 × 2 factorial design was used to test how the type of celebrity endorser and level of product involvement influence the persuasiveness of advertising aimed at young adults. Among 400 respondents, the average age was 21.5 years. A total of 193 male and 207 female respondents participated in the experiment.

Young consumers find virtual idols, online influencers and traditional celebrities attractive. Although virtual idols are the least credible among the three types of celebrity endorsers, young consumers tend to be more convinced by their endorsements of products with low levels of consumer involvement than those with high levels of involvement. Among the three types of celebrity endorsements, young consumers find traditional celebrities the most effective. In addition, young consumers’ attitudes toward celebrity endorsers mediate the impact of celebrity endorsers’ attractiveness and credibility on their attitudes toward the advertisements. The perceived level of product involvement moderates the transfer of meaning from the attitude toward the celebrity endorsers to the attitude toward the advertisement.

First, when choosing celebrity endorsers to advertise products targeting young consumers, marketing communication practitioners should give priority to the endorsers’ perceived credibility, as young consumers have a variety of views about them that can significantly affect their attitudes toward the advertisement. Second, real human celebrity endorsers are more effective than virtual idols in celebrity endorsements. However, virtual idols may be suited for use in advertisements to promote products with low involvement levels, such as soft drinks.

To the best of the authors’ knowledge, this is the first experimental study to attempt to analyze the effectiveness of virtual idols in advertising aimed at young consumers. This is also the first comparative study to introduce virtual idols as celebrity endorsers in product advertising and to compare their effectiveness with that of the two other types of commonly discussed celebrity endorsers, traditional celebrities and online influencers.

Two corrosion inhibitors for closed cooling water systems, nitrite-based and mixture of nitrite and molybdate corrosion inhibitor, are often compared to each other. This study aims to optimize these two inhibitors in terms of concentration and pH for carbon steel protection, with insights into the double layer structure on surface and its impact on corrosion inhibition.

Electrochemical analysis including electrochemical impedance spectroscopy and potentiodynamic test are carried out for quick assessment of corrosion inhibition efficiency and optimization, which is confirmed by immersion test and microscopic analysis. The electronic properties of the surface film are analyzed through Mott–Schottky method which provides new insights into the inhibition mechanism and the role of each component in mixture inhibitor.

Mixture of nitrite and molybdate is shown to present higher inhibition efficiency, owning to the double layer structure. Nitrite alone can form a protective surface film, whereas molybdate leads to an n-type semiconductive film with lower donor density, hence giving rise to a better inhibition effect.

Surface after inhibitor treatment has been carefully characterized to the microscopic scale, implying the effect of micro-structure, chemical composition and electronic properties on the corrosion resistance. Inorganic corrosion inhibitors can be tuned to provide higher efficiency by careful design of surface film structure and composition.

Almost every study on corrosion inhibitor applies such method for quick assessment of corrosion inhibition effect. Mott–Schottky test is one of electrochemical methods that reveals the electronic properties of the surface film. Previous works have studied the surface layer mainly through X-ray photoelectron spectroscopy. This study provides another insight into the surface film treated by nitrite and molybdate through Mott–Schottky analysis, and relates this structure to the corrosion inhibition effect based on multiple analysis including electrochemistry, microscopic characterization, thermodynamics and interface chemistry.

This paper aims to evaluate the progress made in understanding the impact of multi-level institutions on entrepreneurship.

Based on scientific articles published between 1992 and 2017, the authors take a unique focus on both institutional theory applied and research topics of this area. Bibliometric method and systematic literature review method are used.

The results demonstrate that although institutional theory is well prepared for entrepreneurship context operating at different levels, the major knowledge foundation used predominantly focuses on macro and meso level. When it comes to research topics, entrepreneurship is often simplified as the founding of new venture, and the unique venture founding process has rarely been explored.

This paper is the first to provide a full picture of the multi-level institutions and their consequences on different kinds of entrepreneurial activities. The authors’evaluation of this research area also points out directions for future study.

Hedonic social applications have been increasingly popular among health information consumers. However, it remains unclear what motivates consumers to adopt health information in hedonic applications when they have alternative choices of more formal health information sources. Building on the self-determination theory and the affordances lens, this study aims to investigate how different affordances on hedonic social applications affect consumers' basic psychological needs and further influence their intention to adopt health information on such applications.

As TikTok demonstrated great potential in disseminating health information, we developed a model that we analyze using the PLS-SEM technique with data collected from a valid research sample of 384 respondents with health information seeking or encountering experience in TikTok.

The results suggested that health information adoption in hedonic social applications is significantly predicted by the satisfaction of consumers' basic psychological needs, namely autonomy, relatedness and competence. Moreover, the satisfaction of basic psychological needs is positively affected by affordances provided by the hedonic social applications. The hedonic affordances positively influence autonomy satisfaction, while the connective affordances positively affect relatedness satisfaction, and the utilitarian affordances positively support competence satisfaction.

The study indicates that hedonic social applications such as TikTok could be an important channel for consumers to access and adopt health information. The study contributes to the literature by proposing a theoretical model that explains consumers' health information adoption and yields practical implications for designers and service providers of hedonic social applications.

This study examines the relative efficiencies of anti-poverty policies implemented in 28 Chinese provinces.

This study uses meta-frontier undesirable dynamic two-stage data envelopment analysis. The authors divide the poverty reduction process into two stages: agricultural production and poverty reduction. Public expenditure is the input for the second stage, and the population below the poverty line is the undesirable output. The authors compute the efficiencies (overall efficiency, efficiency of each stage and the efficiencies of individual inputs and outputs) using meta-frontier analysis for the 28 provinces.

The results show that: (1) a significant imbalance exists between the eastern and western regions in terms of input-output efficiencies; (2) the poverty reduction stage generally fared better than the agricultural production stage did. In particular, most provinces saw increases in poverty reduction efficiencies between 2013 and 2017; (3) the place-based poverty relief policies introduced in recent years are effective at reducing the poverty rate and reaching the government-set goals and (4) while disposable income has increased steadily over the past few years, income inequality has been exacerbated.

The results show that: (1) a significant imbalance exists between the eastern and western regions in terms of input-output efficiencies; (2) the poverty reduction stage generally fared better than the agricultural production stage did. In particular, most provinces saw increases in poverty reduction efficiencies between 2013 and 2017; (3) the place-based poverty relief policies introduced in recent years are effective at reducing the poverty rate and reaching the government-set goals and (4) while disposable income has increased steadily over the past few years, income inequality has exacerbated.

A large amount of attention and public resources are devoted to fighting poverty and associated market failures in China. The extant literature focuses either on the agricultural production itself or the relationship between human capital and productivity levels. Making use of recent developments of the DEA method, the authors propose a new framework for evaluating the efficiencies of the poverty reduction process. Such a framework has the advantage of giving researchers and policymakers a more detailed diagnosis with regard to the components in the endeavor to eliminate poverty and providing useful information for policymakers to optimize public funds use. Methodologically, the framework is flexible enough to be employed for future research in similar appraisals, at different geographic and scale aggregation levels, for public projects including but not limited to poverty reduction.

The purpose of this paper is to explore the coordination mechanism of cost sharing for green food production and marketing between a food producer and a supplier who both contribute to the sales of green food.

This paper first develops demand functions for both a food supplier and a producer, considering their influence on green degree of food and associated consumers’ acceptances. Then, cost-sharing contracts-based game models are proposed. At last, regarding to optimal supply chain profits and green performance, the proposed contracts and the non-coordination situation are compared and tested by a real case.

When green cost is only shared by one side, the cost-sharing contracts cannot optimally coordinate the food supply chain, but it can improve profits for both the supplier and producer. When consumers’ sensitivity to the green degree of food increases, a mutual cost-sharing contract will bring more profits for both the supplier and producer than those under the non-coordination mode in a decentralized supply chain situation. A real case verifies the conclusions.

The models are in complete information, and the market demand is assumed to be linear to sales price. Mutual cost sharing is only for material processing and food production, which can be extended to include sharing for sales cost. Coordination ideas on the proposed contracts development and solutions for optimal decisions can be applied in the other industries.

The study shows that coordination between a supplier and a producer is needed to improve the food supply chain’s green performance.

This paper first extends the existing profit functions by considering the green efforts of both a supplier and a producer as well as their effects on green degree of products and consumers’ acceptances to the green degree.

This paper aims to develop a new robotic ultrasound system for spine imaging with more anthropomorphic scanning manipulation in comparison with previously reported techniques.

The system evaluates the imaging quality of ultrasound (US) B-scans by detecting vertebral landmarks and groups the images with relatively low quality into several sub-optimal types. By imitating the scanning skills of sonographers, the authors defined a set of adjustment strategies for certain sub-optimal types. In this way, the robot can recollect the US images with high quality by adaptively adjusting the pose of the probe like a sonographer.

The results from phantom experiments and in vivo experiments showed that the proposed method could improve the quality of B-scans during the scanning. The 3 D US volume reconstruction has also verified the feasibility of the proposed method.

This paper demonstrates how to adapt a robotic spinal ultrasound scanning using a preliminary anthropomorphic approach.