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A comparison of electric and viscosity percolation threshold is crucial from the scientific and technical points of view to understand the features and capabilities of heterogeneous graphene composite materials and properly select the functional phase volume. Therefore, the purpose of this paper is to present the analysis of the electrical and rheological percolation thresholds in the polymer–graphene screen printing pastes and the analysis of the relation between these two parameters.

In the paper, the properties of polymer-based pastes with graphene nanoplatelets were tested: paste viscosity and printed layers conductivity. The tests of pastes with different filler content allowed to determine both the electrical and rheological percolation thresholds using power law, according to Kirkpatrick’s percolation model.

The electrical percolation threshold for graphene nanoplatelets (GNPs) in the composite was 0.74 Vol.% when the rheological percolation threshold is observed to be at 1.00 Vol.% of nanoplatelets. The percolation threshold values calculated using the Kirkpatrick’s percolation model were 0.87 and 0.5 Vol.% of GNPs in the paste for electrical and rheological percolation thresholds, respectively.

Recently, GNPs are becoming more popular as the material of the functional phase in screen printing heterophase materials, because of their unique mechanical and electrical properties. However, till date no research presented in the literature is related to the direct comparison of both the electrical and rheological percolation thresholds. Such analysis is important for the optimization of the printing process toward the highest quality of printed conductive paths, and finally the best electrical properties.

The present paper aims to explore how to measure trust as a receptivity force in an intra-organisational knowledge-sharing network with the help of self-developed algorithms of modelling percolations.

In this paper, a completely new methodology is applied by using a sample study of an international company’s financial centre as an example. Computer software has been developed to simulate the network and calculate the percolation thresholds by combining its characteristics, thereby revealing what and to what extent connectivity and trust, respectively, influence knowledge sharing.

The application of computer modelling to build up a percolation network is useful for answering questions about the determinants of knowledge sharing. Arguably, the authors demonstrate how the applied new methodology is superior in addressing how to measure the critical values of trust, connectivity and interaction issues, as well as leading to better insights about how these can be managed. The present paper confirms that trust is an essential factor influencing knowledge sharing and that there is a reciprocal effect between social interaction and trust.

The model provides a useful tool for assessing features of the intra-organisational knowledge-sharing network and thus an important foundation for implementing actions in practice. The findings of this study imply that managers should consider the important role of task-related trust between actors and in general for knowledge sharing. With the help of percolation modelling, the degree of trust in an organisation can be computed, and this provides managers with an approach for managing trust.

The topic of “how can trust be measured” is very important and is becoming even more important now because the financial crisis and other issues are raising questions about trust and moral compass rather than financial data. A percolation-based approach to studying knowledge sharing has not been researched in depth before now, and this study attempts to fill that gap. Fundamentally, this multidisciplinary research adds value to the theoretical foundation of the percolation network and research methodology to be used in social sciences and gives an example of their potential practical implications.

This paper aims to report the conductivity measurement of ten different surfactant-free microemulsions (SFMEs)

The variations of electrical conductivity as a function of water volume fraction are examined at one constant alcohol (or DMF, ethyl lactate, γ-valerolactone)/water, alcohol (or DMF, ethyl lactate, γ-valerolactone)/oil volume ratios for each sample.

Most of the results are consistent with percolation character. The conductive mechanism of these SFMEs is discussed by the percolation model, and it is found that it might be described with the static percolation model below the percolation threshold.

Our report gives a systematic research on the percolation mechanism of as many species of SFMEs as possible by the theoretical models

One of the chief purposes of bibliometric analysis is to reveal the intellectual structure of a knowledge domain. Yet due to the magnitude and the heterogeneous nature of bibliometric networks, some sorts of filtering procedures are often required to make the resulting network interpretable. A co-word analysis of more than 135,000 scholarly publications on Buddhism was conducted to compare the intellectual structure of Buddhist studies in three language communities, Chinese, English and Japanese, over two periods (1957–1986 and 1987–2016). Six co-word similarity networks were created so social network analysis-based community-detection algorithm can be identified to compare major research themes in different languages and eras. The paper aims to discuss this issue.

A series of filtering procedures was performed to exclude less discriminatory keywords and spurious relationships of a large, cross-language co-word network in Buddhist studies. Chief among the filtering heuristics was a percolation-transition based method to determine the similarity threshold that involves observing the relative decrease of nodes in the giant component with the increasing similarity threshold.

It was found that the topical patterns in the Chinese and Japanese scholarship of Buddhism are alike and observably distinct from that of the English scholarship. Furthermore, a far more drastic changes of research themes were observed in the English literature relative to the Chinese and Japanese literature.

The filtering procedures were shown to greatly enhance the modularity values and limited the number of modularity classes; thus, domain expert interpretation is feasible.

The purpose of the study is to explore the potential possibility of using the conductive and piezoresistive nanocomposites that consist of insulating poly(dimethylsiloxane), a very popular silicone polymer, and the amazing properties of carbon nanotubes (CNT) in sensing applications. This nanocomposite is prepared by an optimized process to achieve a high-quality nanocomposite with uniform properties.

The optimized process achieved in this study to provide PDMS/CNT nanocomposite includes the appropriate use of ultrasonic bath, magnetic stirrer, molding and curing in certain circumstances that results in obtaining high-quality nanocomposite with uniform properties. Experiments to characterize the influence of some factors such as pressure, temperature and the impact of CNT’s concentration on the electrical properties of the prepared nanocomposite have been designed and carried out.

The obtained preparing method of this nanocomposite is found to have better homogeneity in comparison to other methods for CNT/PDMS nanocomposite. This nanocomposite has both desirable properties of the PDMS elastomer and the additional conductive CNT, and it can be used to create all-polymer systems. Furthermore, the conductivity values of these nanocomposites can be changed by varying some factors such as temperature and pressure, so that those can be used in temperature- and pressure-sensoring applications.

In the present research, a convenient, inexpensive and reproducible method for preparing CNT/PDMS nanocomposite was investigated. These nanocomposites with the unique properties of both PDMS elastomer and CNTs and also with high electrical conductivity, piezoresistive properties and temperature dependent resistivity can be used in different sensoring applications.

This article gives an overview on the currently available techniques for the measurement of interface pressure or force between (soft) objects. These techniques make use of single sensor elements as well as integrated arrays of sensors to obtain pressure maps. Most of these devices originate from biomedical applications such as the evaluation of wheelchairs and the prevention of pressure ulcers in hospital beds. Today, these technologies are used in a wide range of applications such as computer peripherals, robotics, automotive systems and consumer electronics. These typical applications are considered in the first section. Next, the sensor technologies (and their suppliers) are briefly described and compared. The list of suppliers and technologies is intended as an overview and may not be complete. Finally, new developments in this field are discussed.

The purpose of this paper is to apply an analysis of complex networks to empirically research international agricultural commodity trade and countries’ trading relations. The structure of global agricultural commodity trade is quantitatively described and analysed.

Based on statistical physics and graph theory, the research paradigm of a complex network, which has sprung up in the last decade, provides us with new global perspective to discuss the topic of international trade, especially agricultural commodity trade. In this paper, the authors engage in the issue of countries’ positions in international agricultural commodity trade using the latest complex network theories. The authors at first time introduce the improved bootstrap percolation to simulate cascading influences following the breaking down of bilateral agricultural commodity trade relations.

On a mid-level structure, countries are classified into three communities that reflect the structure of the “core/periphery” using the weighted extremal optimisation algorithm and the coarse graining process. On a micro-level, countries’ rankings are provided with the aid of network’s node centralities, which presents world agricultural commodity trade as a closed, imbalanced, diversified and multi-polar development.

The authors at first time introduce the improved bootstrap percolation to simulate cascading influences following the breaking down of bilateral agricultural commodity trade relations.

The purpose of this paper is to study the interfacial effect on mechanical properties of the cellulose nano crystal (CNC)–shape memory polymer (SMP) composites by using combination of the theoretical and experimental approaches.

SMP composites were fabricated by introducing CNCs into crystalline shape memory polyurethane. The morphological, thermal and mechanical properties were comprehensively investigated. Theoretical approach based upon the percolation model was used to simulate the storage modulus E’ variation of the composites in crystalline and amorphous states, respectively. The classic two-phase percolation model was used for the amorphous-state composites. Furthermore, a three-phase model consisting of interfacial regions was created for the crystalline-state composites.

The deviation of nano fillers mechanical reinforcements was disclosed as the composites triggered thermal transitions. Modified percolation theory involving the interfacial effects greatly enhanced the simulation accuracy.

The study made the traditional percolating theory suitable for dynamic modulus and polymorphs polymers in terms of mechanics, which may extend the potential application.

The findings may greatly benefit the development of novel interfacial reinforcing theory and intelligent polymeric nanocomposites featuring polymorphs and dynamic properties.

The paper aims to substantiate optimization directions of resettable fuses parameters to protect solar arrays from overcurrent.

The method of modeling the electrophysical characteristics of resettable fuses is used.

Resettable fuses currently produced are of little use for protecting photovoltaic cells (PVC) in solar arrays from overcurrent. The volume fraction of the conductive filler should be about 0.15, near the percolation threshold. Thus, reducing the resistance by increasing the amount of filler is not possible. The matrix of the composite should consist of a material with a significant proportion of the crystalline phase to ensure a sharp increase in the composite's volume near the melting point. Using a polymer with a lower melting point instead of polyethylene can reduce the power required to switch a resettable fuses.

The possibility of using resettable fuses based on polymer composite materials with a positive temperature coefficient of resistance to protect photovoltaic solar cells from current overloads is considered. Modeling of the electrophysical characteristics of modern industrial fuses of this type based on polyethylene-nanocarbon composites has been carried out. The limits of their applicability for the protection of photovoltaic solar cells are analyzed. On the basis of the obtained results, the optimization directions of the resettable fuses parameters for use in the protection circuits of PVC of solar array are determined.

The purpose of this paper is to characterise the electrical and mechanical properties of multiwall carbon nanotubes (MWCNTs)-based isotropic conductive adhesives (ICAs). The paper also compares the electrical and mechanical performance of MWCNTs-based ICAs with silver flakes and silver nanoparticles-based ICAs.

The ICAs were formulated with dyglycidyl ether bisphenol A epoxy resin and conductive fillers such as silver flakes, silver nanoparticles and MWCNTs. The four-point probe is used to measure the bulk resistivity of the ICAs.

The results from the study showed that the percolation threshold of the MWCNTs-based ICAs is 1.5 Wt.%. At 3 Wt.%, the drop in bulk resistivity is lower than the conventional ICAs. The addition of silver nanoparticles increased the overall bulk resistivity of the system. The mechanical properties improved with the introduction of carbon nanotubes into the silver flakes–epoxy system.

The results from bulk resistivity and mechanical properties of the MWCNTs could help to formulate MWCNTs-based ICAs with optimum weight fraction.

The paper demonstrates that the addition of MWCNTs to the silver-based ICAs will enhance their mechanical and electrical conductivity. In addition, the optimum weight percentage is also determined, which shows a bulk resistivity value lower along with improved mechanical property with the conventional ICA system.