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The purpose of this paper is to study the influence rules of geometric parameters on deformation of valve slices.

Based on the theory of flexural deformation of elastic thin slice, differential functions of deformation for both single and multi-slices are given and derived in detail. Furthermore, the effects of geometric dimensions on deformation are analyzed particularly by using Matlab/simulink.

The results indicated that the deformation decreases with the increment of fixed ring radius r_a, slice thickness h, and its number n. Meanwhile, the deformation increases with a rise of slice radius r_b, throttle position r_k, the radius ratio λ₁ and thickness ratio λ₂ of slices.

This research can provide some theoretical supports for the parametric and optimal design of adjustable damping shock absorber.

The purpose of this study is to evaluate the effect of graphene, basalt flakes and their synergy on the corrosion resistance of zinc-rich coatings. As the important heavy-duty anticorrosion coatings, zinc-rich coatings provided cathodic protection for the substrate. However, to ensure cathodic protection, a large number of zinc powder made the penetration resistance known as the weakness of zinc-rich coatings. Therefore, graphene and basalt flakes were introduced into zinc-rich coatings to coordinate its cathodic protection and shielding performance.

Three kinds of coatings were prepared; they were graphene modified zinc-rich coatings, basalt flakes modified zinc-rich coatings and graphene-basalt flakes modified zinc-rich coatings. The anticorrosion behavior of painted steel was studied by using the electrochemical impedance spectroscopy (EIS) technique in chloride solutions. The equivalent circuit methods were used for EIS analysis to obtain the electrode process structure of the coated steel system. Simultaneously, the corrosion resistance of the three coatings was evaluated by water resistance test, salt water resistance test and salt spray test.

The study found that the addition of a small amount of graphene and basalt flakes significantly improved the anticorrosion performance of coatings by enhancing their shielding ability against corrosive media and increasing the resistance of the electrochemical reaction. The modified coatings exhibited higher water resistance, salt water resistance and salt spray resistance. The graphene-basalt flakes modified zinc-rich coatings demonstrated the best anticorrosion effect. The presence of basalt scales and graphene oxide in the coatings significantly reduced the water content and slowed down the water penetration rate in the coatings, thus prolonging the coating life and improving anticorrosion effects. The modification of zinc-rich coatings with graphene and basalt flakes improved the utilization rate of zinc powder and the shielding property of coatings against corrosive media, thus strengthening the protective effect on steel structures and prolonging the service life of anticorrosion coatings.

The significance of developing graphene-basalt flakes modified zinc-rich coatings lies in their potential to offer superior performance in corrosive environments, leading to prolonged service life of metallic structures, reduced maintenance costs and a safer working environment. Furthermore, such coatings can be used in various industrial applications, including bridges, pipelines and offshore structures, among others.

This work provides a generic review of the existing data mining ontologies (DMOs) and also provides a base platform for ontology developers and researchers for gauging the ontologies for satisfactory coverage and usage.

The study uses a systematic literature review approach to identify 35 DMOs in the domain between the years 2003 and 2021. Various parameters, like purpose, design methodology, operations used, language representation, etc. are available in the literature to review ontologies. Accompanying the existing parameters, a few parameters, like semantic reasoner used, knowledge representation formalism was added and a list of 20 parameters was prepared. It was then segregated into two groups as generic parameters and core parameters to review DMOs.

It was observed that among the 35 papers under the study, 26 papers were published between the years 2006 and 2016. Larisa Soldatova, Saso Dzeroski and Pance Panov were the most productive authors of these DMO-related publications. The ontological review indicated that most of the DMOs were domain and task ontologies. Majority of ontologies were formal, modular and represented using web ontology language (OWL). The data revealed that Ontology development 101, METHONTOLOGY was the preferred design methodology, and application-based approaches were preferred for evaluation. It was also observed that around eight ontologies were accessible, and among them, three were available in ontology libraries as well. The most reused ontologies were OntoDM, BFO, OBO-RO, OBI, IAO, OntoDT, SWO and DMOP. The most preferred ontology editor was Protégé, whereas the most used semantic reasoner was Pellet. Even ontology metrics for 16 DMOs were also available.

This paper carries out a basic level review of DMOs employing a parametric approach, which makes this study the first of a kind for the review of DMOs.

The purpose of this paper is to examine how game framing and task framing influence experienced meaningfulness (eudaimonia) and perceived enjoyment (hedonia), which, in turn, can account for user participation behavior in citizen science projects.

The authors designed and implemented a citizen science system, Citizen Sort, and used a survey method to investigate to what extent game framing and task framing influence participation behavior. PLS–SEM was used to test research hypotheses with 76 Citizen Sort participants.

Analysis confirmed that game framing and task framing have a significant impact on perceived enjoyment, but showed that only task framing has a direct effect on experienced meaningfulness. The effects of experienced meaningfulness on participation were fully mediated by perceived enjoyment. Content analysis of qualitative data revealed additional insights.

This research is limited due to its sample size and considered as an exploratory study, in which PLS–SEM was used to identify the impact of game framing and task framing as well as support the theory development regarding the dual nature of citizen science games.

This research provided suggestions for scientists, designers and project initiators that game framing and task framing should be effectively integrated to provide enjoyable and meaningful experiences so as to promote user contribution.

This research is one of initial studies which explored the impact of dual nature of citizen science games. The findings of this study provide the groundwork for guidelines and strategies to facilitate user contribution in citizen science projects.

This study focuses on the Critical Success Factors (CSF) for developing sustainable entrepreneurship in the Pakistani telecommunication industry. Despite the efforts made by governments and stakeholders to stimulate sustainable entrepreneurship initiatives, contributions in the telecommunications sector are lacking. Therefore, this study has the major objective of identifying a transformation path for these firms. This is done by providing a theoretical framework for sustainable entrepreneurship in the telecommunications industry, focusing on managerial and operational practices that should be modified according to a set of CSFs identified by experts in Pakistani firms.

This article proposes a novel Multiple Attribute Decision Making (MADM) approach based on Grey Systems Theory (GST) and Best-Worst Method (BWM) while unveiling endogenous relationships among current managerial/operational practices and the CSFs for sustainable entrepreneurship in the telecommunications industry.

CSFs for achieving sustainable entrepreneurship in the Pakistani telecommunications industry were found to rely on a tripod, based on effectiveness, transparency, and accountability that are embedded within the ambit of managerial and operational practices, such as focusing and reducing digital illiteracy, targeting poor communities, helping the young in structuring start-ups.

This article contributes to the MADM research stream by proposing a novel use of the BWM technique based on GST to promote sustainable entrepreneurship CSFs in Pakistani telecommunications firms.

The purpose of this paper is to present a transition detector (TD)-based radiation hardened flip-flop (TDRH-FF) for single event upset (SEU).

With SEU recovery and single event transient (SET) detector mechanism, the TDRH-FF can tolerate SEU during hold mode and generate a warning signal for architecture-level recovery during transport mode when input signal contains SET. Evaluation results show that the TDRH-FF outperforms comparable comprehensive performance.

Simulation results show that 1) the mean pulse width of the correction glitches (at full width half maximum) of TDRH-FF is less than 10 ps; 2) the area overhead of TDRH-FF is similar to the EVFERST-FF, BISER-FF and DNURHL-FF; 3) TDRH-FF has the same average power consumption as SETTOF, and moderate PDP and Ps values among these compared FFs.

In this paper, a TD-based TDRH-FF is proposed to solve the problems in the previous design. And the main contributions of the proposed TDRH-FF are summarized: Minimum size transistors are used in the proposed TD which leads to a considerable decrease in area overheads and propagation delay (resulting in an ignorable correction glitch); and compared with other radiation hardened flip-flop, TDRH-FF outperforms comparable comprehensive performance.

The aim of this study was to examine the early stages of the COVID-19 outbreak and the international communication management of Chinese diplomats as a case for extending the definition of intermestic public diplomacy. The goal was to reveal how Beijing subtly used both domestic and foreign social media to organize a network for communication about COVID-19 and purposefully soften the highly centralized and hierarchical political propaganda of the Communist Party of China (CPC).

Based on the literature on digital public diplomacy, the authors applied the existing concept of intermestic to Chinese politics in order to demonstrate the digitalization of public diplomacy, along with its forms and strategies under an authoritarian regime. A hybrid methodology combining quantitative network analysis and qualitative discourse analysis permits examination of China's intermestic online communication network dynamics, shedding light on how such an intermestic practice promoted Chinese values and power to international publics in the early stages of the COVID-19 crisis.

The authors’ findings extend the implications of intermestic public diplomacy from a democratic context to an authoritarian one. By analyzing the content of public diplomacy and para-diplomatic social media accounts in China and abroad at the beginning of the COVID-19 crisis, the authors outlined China's early crisis management, explaining its intermestic public diplomacy transmission modes and strategies. Moreover, the authors identified changes in the narrative strategies of Chinese diplomats and journalists during this process.

The findings of this study underline that Beijing established a narrative-making virtual communication structure for disseminating favorable Chinese strategic narratives and voices through differentiated communication on domestic and foreign social media platforms. Such intermestic communication strategies were particularly evident and even further weaponized by Beijing in its large-scale Wolf Warrior diplomacy in the spring of 2020. Thus, the study’s findings help readers understand how China digitalized its public diplomacy, its digital communication patterns and strategies.

On the one hand, geopolitical uncertainty and the popularity of social media have contributed to the evolution of the intermestic model of public diplomacy. This model allows actors to coordinate homogenous and differentiated communication practices to deploy their influence. On the other hand, the authors did not examine how intermestic audiences perceive and receive public diplomacy practices. In future studies, scholars should measure the agenda-setting capacity of diplomatic actors by examining the effects of such intermestic communication efforts.

The purpose of this paper is to reveal the temperature rise characteristics of the disc and pads under different load types.

Evolutions of the disc and pads temperature under a stable, gradual changing and sine-wave contact pressures widely used at present are analyzed numerically by using ANSYS software.

The results show that during the loading process, the temperature increases most rapidly under a stable contact pressure, most slowly under a gradual changing contact pressure; the disc temperature rise curves expose saw-shaped character, the closer it is to the friction surface, the more serious the fluctuations will be, the pads temperature rise curves are rather smooth; temperature gradient in the axial direction is higher than that in the other two directions under all of the three types of contact pressure and shows a sine-wave variation under a sine-wave contact pressure.

It indicates that a gradual changing contact pressure should be adopted preferentially in practical application. The simulation results of this work provide theoretical basis for load simulation.

We take a state-stewardship view on corporate governance and executive compensation in economies with strong political involvement, where state-appointed managers act as responsible “stewards” rather than “agents” of the state.

We test this view on China and find that Chinese managers are remunerated not for maximizing equity value but for increasing the value of state-owned assets.

Managerial compensation depends on political connections and prestige, and on the firms’ contribution to political goals. These effects were attenuated since the market-oriented governance reform.

Economic reform without reforming the human resources policies at the executive level enables the autocratic state to exert political power on corporate decision making, so as to ensure that firms’ business activities fulfill the state’s political objectives.

As a powerful social elite, the state-steward managers in China have the same interests as the state (the government), namely extracting rents that should adhere to the nation (which stands for the society at large or the collective private citizens).

As China has been a communist country with a single ruling party for decades, the ideas of socialism still have a strong impact on how companies are run. The legitimacy of the elite’s privileged rights over private sectors is central to our question.

Chinese executive compensation stimulates not only the maximization of shareholder value but also the preservation of the state’s interests.

This study investigates the impact of insider-ownership of publicly traded firms on their performance, cost of debt (COD) and cost of equity. We use a sample of 104 non-finance listed companies of Pakistan for the period from 2006 to 2016. Our study is conducted in Pakistan as a developing country in which insider-ownership is dominant, and a weak external corporate governance mechanism increases the payoffs from insider-ownership. We use feasible generalized least square (FGLS) regression methods to examine these hypotheses. Based on agency theory, we find that insider-ownership enhances firm performance. Furthermore, our results show that insider-ownership reduced the COD and equity. Higher ownership decreases the opportunistic behavior of insiders. It also reduces the creditor’s perception of the likelihood of default on loan payments and reduces agency issues among shareholders. The insider will invest in positive NPV projects which will help maximize shareholders’ wealth and minimize the COD. Similarly, the relationship between insider-ownership and cost of equity is significant but negative. Supporting the convergence of interest increase in ownership helps in aligning the goals of managers and stakeholders whereby the insider will focus on value creation by minimizing equity cost.