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The purpose of this paper is to aim mainly at social public decision-making problems, studies the corresponding relationship between different voting rule combinations and the final results, and discusses the quantitative relationships between group intelligence (final votes) and individual intelligence (everyone) to defend democracy under the circumstance of rapid development of network technology, and crowd intelligence becomes more complicated and universal.

After summarizing the crowd co-decisions of related studies, the standards, frameworks, techniques, methods and tools have been discussed according to the characteristics of large-scale simulations.

The contributions of this paper will be useful for both academics and practitioners for formulating VV&A in large-scale simulations.

This paper will help researchers solve the social public decision-making problems in large-scale simulations.

The purpose of this paper is to bridge the obvious gap presented in research on antecedents of effectuation by building a research model from the perspectives of effectuation and entrepreneurial opportunity.

This paper examines the effects of patterns of opportunity discovery and the innovativeness of entrepreneurial opportunity on the decision-making process of effectuation in new venture creation. Eight hypotheses are put forward and examined by hierarchical multiple logistic regression. The data in this paper are based on the first two rounds of survey data from Chinese Panel Study of Entrepreneurial dynamics.

The empirical results show that patterns of opportunity discovery have significant positive effects (at least partially) on effectuation. Namely, entrepreneurs employing fortuitous discovery tend to use available means and leverage contingency. And with lower innovativeness of opportunity, entrepreneurs are more likely to use affordable loss and leverage contingency.

The study is limited to each dimension of effectuation based on the single-item measure, which cannot completely reflect the effectual construct. More research should to be done to improve measures of effectuation.

The findings are useful for entrepreneurs to make effective decisions whether to choose effectuation in the face of different patterns of opportunity discovery. Besides, it provides the advice on how to cope with the innovativeness of opportunity and seize entrepreneurial opportunities to entrepreneurs.

This paper first systematically studies the effects of entrepreneurial opportunity on effectuation, making up for the obvious gap of research on antecedents of effectuation.

Most research ethic review procedures refer to the principles of safety and security only as sub-criteria of other ethical principles such as the protection of human subjects in research, thereby ignoring the public good aspect of safety and security. In addition, Research Ethics Review Committees (RECs) are usually dominated by philosophers, ethicists, medical doctors, and lawyers with limited practical backgrounds in safety and security risk management. This gap of knowledge restricts ethics reviews in carrying out project-specific safety and security risk management and defers this responsibility to lawmakers and national legal authorities. What might be sufficient in well-regulated and well-understood environments, such as the safety of individuals during clinical research, is insufficient in managing rapidly changing and emerging risks – such as with emerging biotechnologies – as well as addressing the public good dimension of safety and security.

This chapter considers governance approaches to safety and security in research. It concludes that legal mechanisms are insufficient to cope with the complexity of and the fast progress made in emerging technologies. The chapter also addresses the role and potential of research ethics as a safety and security governance approach. It concludes that research ethics can play an important role in the governance of such risks arising from emerging technologies, for example through fundamental rights and public good considerations. However, in reality the current capacity of ethics in the safety and security governance of emerging technologies is limited. It is argued that in newly emerging areas of research currently applied legal compliance–based approaches are insufficient. Instead, inclusion of fundamental risk management knowledge and closer interactions between scientists, safety, and security experts are needed for effective risk management. Safety and Security Culture provide frameworks for such interactions and would well complement the current legal compliance–based governance approaches in research ethics.

Here, attempts have been made to explore the possible use of Marine waste as filler materials into the bio-fibre composites. Clam shell is a type of marine waste which belongs to the class of Bivalvia. It is mainly made of aragonite crystalline polymorphs. This paper aims to develop a new class of natural fibre composite in which jute fibre as reinforcement, epoxy as matrix and clam shell, as particulate microsphere filler. The study investigates the effects of different amounts of clam shell powder on the kinetics of water absorption of jute fibre-reinforced epoxy composite. Two different environmental conditions at room temperature, i.e. distilled water and seawater, are collected for this purpose. Moisture absorption reduces when clam shell is added to the jute-epoxy composite. The curve of water absorption of jute-epoxy composites with filler loading at both environmental conditions follows as Fickian behaviour.

Hand lay-up technique to fabricate the composite – Experimental observation

The incorporation of Clam shell filler in jute epoxy composite modified the water absorption property of the composite. Hence the present marine waste is an potential filler in jute fibre reinforced polymer composite.

The paper demonstrates a new class hybrid composite material which uses a marine waste as important phase in the bio-fibre-reinforced composite. It is a new work submitted for original research paper.

The purpose of this paper is to design the crown‐type phosphate ionic liquid additive which can dissolve in poly(ethylene glycol) (shortened to PEG) completely, and evaluate the tribological properties as additive in PEG for steel/steel contacts.

To improve the solubility and the tribological performance of ionic liquid additive in PEG, the crown‐type phosphate ionic liquid additive was prepared. The tribological properties of the crown‐type phosphate ionic liquid additive in PEG were evaluated at different concentrations and rubbing frequencies on an Optimol SRV oscillating friction and wear tester. The morphology and chemical compounds of the wear scars were analyzed by scanning electron microscope (SEM) and X‐ray photoelectron spectroscopy (XPS).

The experimental results show that the crown‐type phosphate ionic liquid additive applied in based oil exhibits better tribological properties for steel/steel contacts at different loads, concentrations and rubbing frequencies. It could improve the anti‐wear ability and reduce the friction coefficients as the increased concentration. By the SEM and XPS analysis, it is found that there were the effective boundary lubricant films in the worn surface. The boundary films were composed of various tribochemical products, ferric oxide, ferric phosphate and pyrophosphate, together with the absorbed films.

Compared with the poor miscibility of some ionic liquid in PEG, the crown‐type phosphate ionic liquid additive can dissolve in PEG perfectly. It can improve the anti‐wear ability and reduce the friction coefficient of PEG at different concentrations and rubbing frequencies.

To understand the service performance of full ceramic ball bearings under extreme working conditions and improve their service life, dynamic characteristic tests of full ceramic ball bearings under ultra-low temperature conditions were carried out by a low-temperature bearing life testing machine, and temperature rise and friction were measured under extreme low-temperature environment.

The heat-flow coupling model of bearing was established by CFD software, and the test results were further analyzed.

The results show that the temperature rise of the bearing is not obvious in the liquid nitrogen environment. With the increase of the chamber temperature, the lubrication state of the bearing changes, resulting in the temperature rise of the outer ring of the bearing. As the temperature of the test chamber increases, the friction force on the bearing increases first and then decreases under the action of multifactor coupling.

The research results provide test data and theoretical basis for the application of all-ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

The research results provide test data and theoretical basis for the application of full ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

The research results provide test data and theoretical basis for the application of full ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

The research results provide test data and theoretical basis for the application of full ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

For most practical control system problems, the state variables of a system are not often available or measureable due to technical or economical constraints. In these cases, an observer-based controller design problem, which is involved with using the available information on inputs and outputs to reconstruct the unmeasured states, is desirable, and it has been wide investigated in many practical applications. However, the investigation on a discrete-time singular Markovian jumping system is few so far. This paper aims to consider an observer-based control problem for a discrete-time singular Markovian jumping system and provides a set of easy-used conditions to the proposed control law.

According to the connotation of the separation principle extended from linear systems, a mode-dependent observer and a state-feedback controller is designed and carried out independently via two sets of derived necessary and sufficient conditions in terms of linear matrix inequalities (LMIs).

A set of necessary and sufficient conditions for an admissibility analysis problem related to a discrete-time singular Markovian jumping system is derived to be a doctrinal foundation for the proposed design problems. A mode-dependent observer and a controller for such systems could be designed via two sets of strictly LMI-based synthesis conditions.

The proposed method can be applied to discrete-time singular Markovian jumping systems with transition probability p_ij > 0 rather than the ones with p_ii = 0.

The formulated problem and proposed methods have extensive applications in various fields such as power systems, electrical circuits, robot systems, chemical systems, networked control systems and interconnected large-scale systems. Take robotic networked control systems for example. It is recognized that the variance phenomena derived from network transmission, such as packets dropout, loss and disorder, are suitable for modeling as a system with Markovian jumping modes, while the dynamics of the robot systems can be described by singular systems. In addition, the packets dropout or loss might result in unreliable transmission signals which motivates an observer-based control problem.

Both of the resultant conditions of analysis and synthesis problems for a discrete-time singular Markovian jumping system are necessary and sufficient, and are formed in strict LMIs, which can be used and implemented easily via MATLAB toolbox.

Workplace bullying has become a major challenge across the globe as it is associated with negative outcomes. Therefore, this study was designed to assess the impact of workplace bullying on knowledge hiding through emotional exhaustion. The study further investigated the moderating role of workplace friendship to reduce the detrimental effect of workplace bullying on knowledge hiding.

The study collected data from 358 nurses working in three large cities (Karachi, Islamabad and Lahore) of Pakistan in two lags to tackle the issue of common method bias.

The study applied structural equation modeling with maximum likelihood method using AMOS to test the hypotheses. The study noted that workplace bullying elevates emotional exhaustion and knowledge hiding among nurses; whereas, workplace friendship was noted as an essential factor to control adverse effects of workplace bullying on knowledge hiding.

The study used a cross-section design that restricts causality. However, the findings of this study add to the conservation of resources theory by providing insights into the role of workplace friendship in reducing the relationship between workplace stressors (bullying) and negative behaviors (knowledge hiding). The study also suggests healthcare administration foster workplace friendship to cope with the negative outcomes of workplace bullying.

Drawing upon conservation of resources, this study explored the moderating role of workplace friendship between workplace bullying and knowledge hiding.

In this paper, the author defines the function B¯i,jδ,k(n), the number of singular overpartition pairs of n without multiples of k in which no part is divisible by δ and only parts congruent to ± i, ± j modulo δ may be overlined.

Andrews introduced to combinatorial objects, which he called singular overpartitions and proved that these singular overpartitions depend on two parameters δ and i can be enumerated by the function C¯δ,i(n), which gives the number of overpartitions of n in which no part divisible by δ and parts ≡ ± i(Mod δ) may be overlined.

Using classical spirit of q-series techniques, the author obtains congruences modulo 4 for B¯2,48,3(n), B¯2,48,5 and B¯2,412,3.

The results established in this work are extension to those proved in Andrews’ singular overpatition pairs of n.

The study aims to the distribution rule of lubricating oil film of full ceramic ball bearing and improve its performance and life.

The paper established an analysis model based on the fluid–solid conjugate heat transfer theory for full ceramic ball bearings. The distribution of flow, temperature and pressure field of bearings under variable working conditions is analyzed. Meanwhile, the mathematical model of elastohydrodynamic lubrication (EHL) of full ceramic ball bearings is established. The numerical analysis is used to study the influence of variable working conditions on the lubricant film thickness and pressure distribution of bearings. The temperature rise test of full ceramic ball bearing under oil lubrication was carried out to verify the correctness of simulation results.

As the speed increased, the oil volume fraction in full ceramic ball bearing decreased and the surface pressure of rolling element increased. The temperature rise of full ceramic ball bearings increases with increasing speed and load. The lubricant film thickness of full ceramic ball bearing is positively correlated with speed and negatively correlated with load. The pressure of lubricating film is positively correlated with speed and load. The test shows that the higher inner ring speed and radial load, the higher the steady-state temperature rise of full ceramic ball bearing. The test results are in high agreement with simulation results.

Based on the fluid–solid conjugate heat transfer theory and combined with Reynolds equation, lubricating oil film thickness formula, viscosity temperature and viscosity pressure formula. The thermal analysis model and EHL mathematical model of ceramic ball bearings are established. The flow field, temperature field and pressure field distribution of the full ceramic ball bearing are determined. And the thickness and pressure distribution of lubricating oil film in the contact area of full ceramic ball bearing were determined.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2023-0126/