Search results

The purpose of this paper is to develop the models of the dielectric permittivity dispersion of heterogeneous systems based on semiconductors to a level that would allow to apply effectively the method of broadband dielectric spectroscopy for the study of electronic processes in ceramic and composite materials.

The new approach for determining the complex dielectric permittivity of heterogeneous systems with semiconductor particles is used. It includes finding the analytical expression of the effective dielectric permittivity of the separate semiconductor particle of spherical shape. This approach takes into account the polarization of the free charge carriers in this particle, including capturing to localized electron states. This enabled the authors to use the known equations for complex dielectric permittivity of two-component matrix systems and statistical mixtures.

The presented dispersion equations establish the relationship between the parameters of the dielectric spectrum and electronic processes in the structures like semiconductor particles in a dielectric matrix in a wide frequency range. Conditions of manifestation and location of the different dispersion regions of the complex dielectric heterogeneous systems based on semiconductors in the frequency axis and their features are established. The most high-frequency dispersion region corresponds to the separation of free charge carriers at polarization. After this region in the direction of reducing of the frequency, the dispersion regions caused by recharge bulk and/or surface localized states follow. The most low-frequency dispersion region is caused by recharging electron traps in the boundary layer of the dielectric matrix.

Dielectric dispersion models are developed that are associated with: electronic processes of separation of free charge carriers in the semiconductor component, recapture of free charge carriers in the localized electronic states in bulk and on the surface of the semiconductor and also boundary layers of the dielectric at the polarization. The authors have analyzed to situations that correspond applicable and promising materials: varistor ceramics and composite structure with conductive and semiconductor fillers. The modelling results correspond to the existing level of understanding of the electron phenomena in matrix systems and statistical mixtures based on semiconductors. It allows to raise efficiency of research and control properties of heterogeneous materials by dielectric spectroscopy.

The purpose of this paper is to explore and develop specific models of the kinetics of isothermal depolarization currents (IDC) and the corresponding methods for the diagnostics of the physical parameters of localized electronic states (LES) in heterogeneous materials and corresponding polycrystalline semiconductor materials and heterogeneous insulators with a conductive phase.

Analysis of the kinetics of isothermal depolarization on the basis of the models allowed the authors to establish a sufficient level of their information content. This also allowed the possibility of applying for research and testing of heterogeneous structures of electronic technique.

Optimal conditions (full charge of LES on one side of the object and full discharge on the other side) and the correction factors, allowed the researchers to find concentration of these states using the developed models.

This paper uses a particular method to determine and test the parameters of LES, including operations of determining the time constant of IDC signal from its frequency spectrum, finding the ionization energy and the capture coefficient of electrons from the temperature dependence of this time constant, determining the concentration based on the integration of the time dependence of current density of IDC in the time interval that boundaries are determined from the limited range of frequencies of the signal IDC spectrum has been proposed, validated and verified by numerical experiments.

The purpose of this paper is to develop a generalized model of the nonlinear conductivity of varistor ceramic suitable for solving problems of prediction and control of ceramic nonlinearity, stability of varistor properties.

The modeling of current-voltage characteristic of the intergranular barrier in metal oxide varistor ceramics is based on the development of the algorithm. It includes all the known mechanisms of electrotransfer in a wide range of voltages and currents of the current-voltage characteristics, and also takes into account the deviation of the barrier form the Schottky barrier.

The models of double Schottky barrier and double barrier of arbitrary form, as well as the algorithms for calculating the current-voltage characteristics of a single intergranular potential barrier and a separate “microvaristor” with the use of the most well-established understanding of the main mechanisms of electrical are developed. The results of current-voltage characteristics modeling correspond to the existing understanding of the nonlinear electrical conductivity varistor ceramics are based on zinc oxide. The model of double barrier of arbitrary form takes into account the deviation of the barrier form the Schottky barrier which is important in predicting the deformation of the current-voltage characteristics of the varistor products in the process of degradation.

The relation between the form of the current-voltage characteristic and the distribution profile of the donor concentration in the surface regions of the semiconductor crystallites constituting the intergranular potential barrier is established. The accumulation of donors in the space charge region leads to the increase in the current on the prebreakdown region of the current-voltage characteristic and the reduction of voltage corresponding to the breakdown region beginning of the current-voltage characteristic. The significant role of the interlayer in the formation of current-voltage characteristic of the intergranular potential barrier is shown.

A regular crystal structure in which the lattice sites are occupied by the various isotopes of the same chemical element has enormous potential for the storage of information. Based on this idea, a model of an alternative genetic code is discussed in which elementary codons are represented by the various spatial combinations of different isotopes. In crystals with relatively large unit cell (e.g. boron) a single unit cell may play a role of an elementary isotopic codon. Some mechanisms of information transfer in such “isotopic biology” may involve localized electronic and vibrational states as well as isotopic variations of the diffusivity. Some possibilities of experimental testing of the proposed hypothesis are indicated.

Aim of the present monograph is the economic analysis of the role of MNEs regarding globalisation and digital economy and in parallel there is a reference and examination of some legal aspects concerning MNEs, cyberspace and e‐commerce as the means of expression of the digital economy. The whole effort of the author is focused on the examination of various aspects of MNEs and their impact upon globalisation and vice versa and how and if we are moving towards a global digital economy.

The purpose of this paper is modeling the effect of negative capacitance in the capacitance-voltage characteristic of the intergranular potential barrier of varistor structure.

The modeling of the capacitance-voltage characteristic of the intergranular barrier in metal oxide varistor ceramics is based on the development of the algorithm. It includes all the known mechanisms of electrotransfer in a wide range of voltages and currents, and also takes into account the voltage drop on the intergranular interlayer of intergranular potential barrier.

The models and algorithms for calculating the capacitance-voltage characteristics of a single intergranular potential barrier with the use of the most established understanding used at the interpretation of the nonlinear conductivity intergranular barrier are developed. The results of the capacitance-voltage characteristics modeling correspond to the existing understanding of the electrical properties on the ac current varistor ceramics are based on zinc oxide. The model allows to predict the behavior of varistors on the alternating current (voltage).

It is established that the recharge of the surface localized states occurs when a voltage is applied to the varistor structure, it can lead to a relaxation decrease in the width of the potential barrier overcome by tunneling electrons in the field emission from the conduction band of the one crystallite in the conduction band of the other crystallite and thus to the current backlog of applied voltage on the phase (i.e. the expression of the negative capacitance effect).

The purpose of this study is to examine American multinational corporations' (MNC's) web site standardization in Poland and the Czech Republic. The theoretical framework was adopted from global marketing strategy (GMS) theory, which focuses on three primary strategies: strategy to create a uniform brand image; strategy to appeal to cross‐border segments; and strategy to express culturally bound meaning. To this end, MNCs are posited to pursue the standardization of corporate visual components and web site functions, and the localization of textual information.

Using web site content analysis techniques, the similarity between the home (US) and host (Polish or Czech) sites is evaluated, and the existence of web site functions in each site is coded. As a secondary reference point, German sites are also examined. Two native coders per country are employed, and the reliability scores are deemed to be satisfactory. Multivariate analyses, including a multiple discriminant analysis and a multiple correspondence analysis, were applied to test the principal thesis of the study.

The findings suggest that American MNCs tend to apply a high level of visual components in Polish and Czech sites. However, the level of standardization in textual messages is notably low. Specifically, it appears that the textual information in Polish sites is highly localized – despite their uniform visuals, in the same manner as German sites. In addition, MNCs use web site functions in Polish sites to a similar extent to their home US sites, but to a much lesser extent in Czech sites.

The findings of this study make an important contribution to the literature, electronic commerce research in this region is extremely scarce. In addition, the theoretical framework, based on GMS theory, appears to be a useful stepping‐stone in this area. Along with recent findings in international advertising standardization, this study also provides unique evidence that European integration affects firms' marketing standardization strategy, not only offline, but also in the online marketing environment.

The theoretical findings serve as a foundation for further research into understanding sulfide-based solid-state electrolytes, ultimately advancing the progress of all-solid-state batteries.

The electronic properties of Li₇P₃S₁₁ are thoroughly explored through first-principles calculations.

This investigation encompasses the intricate atom-dominated valence and conduction bands, spatial charge density distribution and the breakdown of atom and orbital contributions to van Hove singularities. Additionally, the compound’s wide and discrete energy spectra reflect the substantial variations in bond lengths and its highly anisotropic geometric structure. The complex and nonuniform chemical environment indicates the presence of intricate hopping integrals.

This study provides valuable insights into the critical multiorbital hybridizations occurring in the Li-S and P-S chemical bonds. To validate the theoretical predictions, experimental techniques can be employed. By combining theoretical predictions with experimental data, a comprehensive understanding of the geometric and electronic characteristics of Li₇P₃S₁₁ can be achieved.

This article reviews areas of common concern between librarians on the one hand and scholars on the other as they each attempt to pursue their work in an era of electronic information. The issues require the attention of both librarians and scholars, and it is argued that both communities need now to talk more extensively with one another in an effort to re‐think the fundamental role of the university library in the coming years. The function and importance of Integrated Scholarly Information Systems (ISIS) are discussed with examples to illustrate the ways in which scholars are likely to acquire and integrate electronic information in the future. The article concludes with reflections on two contradictory trends that are emerging in scholarly research with the expansion of electronic research systems.

The limited success of electronic health records (EHRs) implementation in the healthcare services in general, and a national EHR in particular, requires better understand and documentation of the current drivers and inhibitors of EHR adoption, together with a definition of a national EHR. This paper aims to address these issues.

Factors affecting EHR adoptions are elicited from extant literature and the stakeholder/actor framework is used as the theoretical framework. The multiple case study approach is used as the research method, and data are collected in Ireland and Israel by interviews and analysed using text coding methods.

Factors elicited in the literature are generally corroborated, yet the salient factor on the localized perspective appears to be the degree of centralization of the healthcare services; while different factors affect the national perspective. In summary, it seems that Israel is more ready for national EHR implementation than Ireland due to the high level of computerization and high levels of integration of primary and secondary care patient data.

Contribution to research is in the definition of a national EHR, the illustration of various levels of analysis and their relative impacts on EHR adoption, the analysis framework, and by showing that EHR adoption is a top‐down, change management process.

EHR adoption should be driven by a powerful actor in the healthcare sector addressing the need for a high level of integration within and between care levels, while focusing on clinicians' requirements. Technological and legislative infrastructures are mandatory for establishing a national EHR.

Data for this study are collected in two countries that represent different healthcare structures, one being highly centralized while the other is just the opposite. These differences provide an additional interesting lens through which factors affecting EHR adoption can be assessed. As far as we know, not many previous studies have compared EHR adoption across two diverse healthcare systems.