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This paper reports on the development of a repulsive type magnetic bearing system and the importance of permanent magnet (PM) configuration on the attenuation of radial disturbance. A new configuration of the permanent magnet of the bearing system resulting in improved stiffness characteristics in the radial direction has been described. Prototype models have been designed and developed in our laboratory and experiments carried out.

From the point of view concerned with the development of the information, oriented functions in social activities, recently power consumption has rapidly increased. On the other hand, ability of power supply has not been increased to follow this increasing consumption, because it is difficult to construct new power generation plants. Therefore, reserve capacity of power supply is going to be decreased and power down has become a serious problem. To prevent the serious power down and to maintain a stable power supply, we had already proposed a passive fault current limiter using a permanent magnet with high coercive force, high remanent magnetic flux density and a ferrite core with high permeability, low saturated flux density compared to that of a permanent magnet. In this paper, the flux distribution of the limiter is investigated using the three dimensional finite element method.

The purpose of this paper is to test the measurement performances of a planar‐type meander sensor installed in robot foot in order to examine its potential application as ground reaction force sensor.

A planar‐type meander sensor is composed of two pairs of meander coils. Variation of input inductance between coils serves as a measure of small displacements in a plane. Pairs of meander coils are installed in an actuated robot foot to measure displacements proportional to normal or tangential components of ground reaction force which acts upon the foot. The sensor was modeled by the concept of partial inductance and a new simulation tool was developed based on this concept.

Pairs of meander coils were tested against angular displacements, and results showed that the sensor gives correct information about displacement regardless how the foot touches the ground with its whole area. Deviations between position of computed and real acting point of ground reaction force are relatively small. Owing to good results obtained, a miniaturized sensor was developed having the same performances as previously developed prototype.

This paper presents initial work in implementing a planar‐type meander sensor in robot foot as to measure ground reaction force. Developed simulation tool gives accurate analysis of inductance variation of meander structures. In addition, the measurement error and sensor's nonlinearity are analyzed. Calculated results show a good agreement with experimental results. Hence, miniaturized sensor, easier for implementation, is proposed.

Present 3D electromagnetic simulators have high accuracy but they are time and memory expensive. Owing to a fast and simple expression for inductance is also necessary for initial inductor design. In this paper, new efficient methods for total inductance calculation of meander inductor, are given. By using an algorithm, it is possible to predict correctly all inductance variations introduced by varying geometry parameters such as number of turns, width of conductor or spacing between conductors.

The starting point for the derivation of the recurrent formula is Greenhouse theory. Greenhouse decomposed inductor into its constituent segments. Meander inductor is divided into straight conductive segments. Then the total inductance of the meander inductor is a sum of self‐inductances of all segments and the negative and positive mutual inductances between all combinations of straight segments. The monomial equation for the total inductance of meander inductor has been obtained by fitting procedure. The fitting technique, using the method of least squares, finds the parameters of the monomial equation that minimize the sum of squares of the error between the accurate data and fitted equation. The paper presents new expression for inductance of meander inductor, in the monomial form, which is suitable for optimization via geometric programming. The computed inductances are compared with measured data from the literature.

The first, recurrent, expression has the advantage that it indicates to the designer how the relative contributions of self, positive, and negative mutual inductance are related to the geometrical parameters. The second expression presents the inductance of the meander inductor in the monomial form, so that the optimization of the inductor can be done by procedure of the geometric programming. Simplicity and relatively good accuracy are the advantages of this expression, but on the other hand the physical sense of the expression is being lost. Thus, the effects of various geometry parameters on inductance are analyzed using two expressions and the software tool INDCAL.

Applied flexible efficient methods for inductance calculation of meander inductor are able to significantly increase the speed of RF and sensor integrated circuit design.

For the first time a simple expression for fast inductance calculation for meander inductor in monomial form is presented. It is explained how such an expression is generated, which can be directly implemented in circuit simulators.

Magnetic induction tomography (MIT) is a tomographic imaging technique with a wide range of potential industrial applications. Planar array MIT is a convenient setup but unable to access freely from the entire periphery as it only collects measurements from one surface, so it remains challenging given the limited data. This study aims to assess the use of sparse regularization methods for accurate position and depth detection in planar array MIT.

The most difficult challenges in MIT are to solve the inverse and forward problems. The inversion of planar MIT is severely ill-posed due to limited access data. Thus, this paper posed a total variation (TV) problem and solved it efficiently with the Split Bregman formulation to overcome this difficulty. Both isotropic and anisotropic TV formulations are compared to Tikhonov regularization with experimental MIT data.

The results show that Tikhonov method failed or underestimated the object position and depth. Both isotropic and anisotropic TV led to accurate recovery of depth and position.

There are numerous potential applications for planar array MIT where access to the materials under testing is restrict. Sparse regularization methods are a promising approach to improving depth detection for limited MIT data.

The stability and input voltage saturation is a common problem associated with an active magnetic bearing (AMB) system. The purpose of this paper is to design a control scheme that stabilizes the single degree of freedom AMB system and also tackle the problem of input voltage saturation in the AMB system.

The proposed control technique is a combination of two separate control schemes. First, the Backstepping control scheme is designed to stabilize and control the AMB system and then Chebyshev neural network (CNN)-based compensator is designed to tackle the input voltage saturation when the system control action is saturated.

The mathematical and simulation results are presented to validate the effectiveness of proposed methodology for single-degree freedom AMB system.

This paper introduces a CNN-based compensator with Backstepping control strategy to stabilize and tackle the problem of input voltage saturation in the 1-DOF AMB systems.

The purpose of this study is to determine the contamination level in natural water resources because the tremendous development in the agriculture sector has increased the amount of contamination in natural water sources. Hence, the water is polluted and unsafe to drink.

Three types of sensor arrays were suggested: parallel, star and delta. The simulation of all types of sensor array was carried out to calculate the sensors’ impedance value, capacitance and inductance during their operation to determine the best sensor array. The contamination state was simulated by altering the electrical properties values of the environmental domain of the model to represent water contamination.

The simulation results show that all types of sensor array are sensitive to conductivity, σ, and permittivity, ɛ (i.e. contaminated water). Furthermore, a set of experiments was conducted to determine the relationship between the sensor’s impedance and the water’s nitrate and sulphate contamination. The performance of the system was observed where the sensors were tested, with the addition of distilled water with different concentrations of potassium nitrate and potassium sulphate. The sensitivity of the developed sensors was evaluated and the best sensor was selected.

Based on the outcomes of the experiments, the star sensor array has the highest sensitivity and can be used to measure nitrate and sulphate contaminations in water.

The star sensor array presented in this paper has the potential to be used as a useful low-cost tool for water source monitoring.

The purpose of this paper is to apply the lattice Boltzmann method (LBM) to simulate mixed flow, which combines natural convection for temperature difference and forced convection for lid driven, in a two‐dimensional rectangular cavity over a wide range of aspect ratios (A), Rayleigh numbers (Ra) and Reynolds numbers (Re).

The LBM is applied to simulate the mixed flow. A multi‐relaxation technique was used successfully. A scale order analysis helped the understanding and predicting the overall heat transfer.

In the considered lid driven cavity, the Richardson number emerges as a measure of relative importance of natural and forced convection modes on the heat transfer. An expression of the overall heat transfer depending on the cavity slender (A) is deduced. The validity of the obtained expression was checked in mixed convection under the condition of low Richardson number (Ri) and the limitation condition was deduced.

This paper has implications for cooling system optimization and LBM technique development.

This paper presents a new cooling configuration, avoiding critical situation where the opposing effect induce weak heat transfer; and a stable and fast LBM approach allowing complex geometry treatment.

Seeks to fill some of the gaps in the business literature regarding the consumer market in Japan. Accomplishes this through a replication of the classic 1974 work of Davis and Rigaux relating to family purchase decision making. An egalitarianism scale was included for the final analysis to allow for differences in couple perceived traditionality‐modernism. Finds that the heavily patriarchal orientation of Japan still exists with husbands exerting heavy influence in the final stage of the decision‐making process and offers suggestions for management.

This paper examines the need for international regulation of financial markets and suggests the possible role that a global financial supervisor might play in providing effective regulation of international financial markets. The first part discusses the nature of systemic risk in the international financial system and the necessity for international Minimum Standards of prudential supervision for banking institutions. The second part examines the efforts of the Basel Committee on Banking Supervision to devise non‐binding international standards for managing systemic risk in financial markets. Recent financial crises in Asia, Russia and Latin America suggest, however, that informal efforts by international bodies such as the Basel Committee are inadequate to address the risk of systemic failure in financial systems. The third part therefore argues that efficient international financial regulation requires certain regulatory functions to be performed by a global supervisor acting in conjunction with national regulatory authorities. These functions should involve the authorisation of financial institutions, generation of rules and standards of regulatory practice, surveillance of financial markets, and coordination with national authorities in implementing and enforcing such standards.