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We present a semi‐analytic approach based on a multipole expansion for the solution of two‐dimensional, linear electrostatic problems with piecewise homogeneous regions. This method, called multiple multipole method, leads to more accurate solutions and requires less computation time than the usual numerical methods, especially in such problems where the capacitance of a system of electrodes with different dielectric rods in between, both of arbitrary cross section, is to be calculated with precision.

The MMP method, which was already successfully applied to two‐dimensional electrostatic problems, is extended in this paper to solve dynamic cases. Different techniques are introduced to get better results and to save computation time. Some waveguide and scattering calculations show the possibilities of this method.

A two‐dimensional electromagnetic field model of a railway track and traction line is used to determine the equivalent track distributed transmission line parameters in the frequency range DC to 30kHz. The model is solved using the finite‐element method to find the minimum energy condition for two conditions: current excitation to obtain the resistance and inductance, and voltage excitation for the conductance and capacitance. The results have been confirmed using practical test data, and their application is illustrated in a time‐domain circuit simulation to model interference between power and signalling currents in a 750V DC electric railway.

An extension of the coupling of the generalized multipole technique, adapted to the infinite domain, with the standard finite elements in the examined area, to problems with rotational symmetry is presented. The multipole expansion in the infinite domain is the superposition of three‐dimensional multipoles distributed uniformly at several circles. The circles build multipole rings. The theoretical basis for building the multipole rings and for taking symmetry into account are given. The method is verified by calculating electrostatic and magnetostatic problems for which analytical solutions exist. Verification encompasses potential distribution as well as calculation of equivalent lumped parameters, i.e. capacitance and inductance.

In the paper establishing the benchmark tests for open boundary problems as it has been done in other branches of electromagnetic field calculations is proposed. Consideration is given to what input and output data should be defined for the benchmark problems. In the appendix one proposal for benchmark problems is presented.

The purpose of this paper is to investigate of the ultra‐wide band (UWB) characteristics of a conical antenna covered by an electromagnetic band‐gap (EBG) structure composed of alternating high‐ and low‐permittivity dielectric spherical shells.

A finite difference time domain in spherical coordinates is implemented in order to characterize the antenna's performance and waveform fidelity in case an UWB pulse is used. The method of projected effective permittivity is used in order to treat accurately the dielectric interfaces between the dissimilar spherical shells.

The design achieves a very wide impedance bandwidth above 5.5 GHz and presents UWB radiation characteristics and high average gain over the whole bandwidth. The radiation patterns are monopole‐like and their frequency dependence is small in the whole UWB frequency band. A time domain study has shown that the antenna distorts the excitation pulse in a moderate way.

In this paper, a quasi‐planar wideband conical antenna coated on a dielectric EBG structure is proposed for what is believed to be the first time. It is mechanically stable and, relatively easy to build and integrate with the planar circuits.

Identifies key activities that network users can perform in order to use the network effectively. Offers recommended reading, from beginner to expert user status. Explains some commonly used terms (e.g. Turbo Gopher with Veronica!). Lists useful Internet resources.

Illegitimacy is widely identified as a cause of revolution and other forms of transformative political change, yet when and how it affects these processes is ambiguous. We examine when and how illegitimacy affects the stability of political regimes through a historical analysis of South Africa's National Party (NP) and its apartheid regime, which lasted from 1948 to 1994. Many scholars of South Africa identify the regime's illegitimacy as a catalyst for the end of apartheid. Yet, consistent with assertions that illegitimacy does not result in political instability, the NP maintained power for decades despite a domestic crisis of legitimacy and a global movement that decried the apartheid regime's illegitimacy. Interrogating this contradiction, we detail how the regime's illegitimacy contributed to the negotiated revolution in South Africa when it resulted in unacceptable costs for the allies that the government depended on for survival, motivating those allies to withdraw support. Building on our findings, we detail how turning attention to the ways that illegitimacy affects relationships with allies – rather than particular outcomes, such as revolution or state failure – allows us to account for variation in both when and how illegitimacy matters.

The construction of regional financial center can gather a large amount of financial production elements and capital, which plays an important role in promoting regional economic development. Based on this, the analysis of the planning and design of regional financial center based on the financial structure was studied. Firstly, the research progress of regional financial center and financial structure was expounded. Then, on the basis of the functional demand of the financial center, the planning and design method of the regional financial center was put forward. The regional center building in Nanjing was taken as an example, and the specific planning and design of the traffic, super high-rise landmark buildings, squares and other buildings were analyzed with the advantage of location. The research shows that the design and planning of the regional financial center can provide the new coordinates of globalization for the local finance.