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To provide a new and simple inverse rotor time constant identification method which can be used to update an indirect rotor field oriented controlled (IRFOC) induction motor algorithm.

Two different equations are used to estimate the rotor flux in the stator reference frame. One of the equations is a function of the rotor time constant, rotor angular velocity and the stator currents. The other equation is a function of measured stator currents and voltages. The equation that uses the voltage and the current signals of the stator serves as reference model, however, the other equation works as an adjustable model with respect to the variation of the rotor time constant. Voltage signals used in the reference model equation are obtained from the measured DC bus voltage and the inverter gating signals. The proposed scheme is verified using a MATLAB/SIMULINK model for two different motors and experimentally using a DSP development tool (MCK 243) supplied by Technosoft S.A.

The proposed estimator was able to successfully track the actual value of the inverse rotor time constant for different load torque and speed operating conditions. Increased oscillations in the estimated inverse rotor time constant appeared at lower speeds (below 10 per cent of rated speed) due to drift in a PI regulator (used at the estimator side), which was tuned under rated operating conditions and using parameters nominal values.

This estimation scheme is limited when near zero speed operation is demanded; otherwise it gives a simple and practical solution. A suggested way out of this, is to provide a self‐tuning controller that can automatically adjust even for zero speed operation, or to automatically disconnect the estimator and take the most updated value as long as the operating speed is below a predetermined value.

This paper presented a new inverse rotor time constant estimator for an IRFOC induction motor application and in conjunction rotor flux was estimated without voltage phase sensors.

This paper aims to reviewed analytical methodologies, i.e. lumped parameter magnetic equivalent circuit (LPMEC), magnetic co-energy (MCE), Laplace equations (LE), Maxwell stress tensor (MST) method and sub-domain modelling for design of segmented PM(SPM) consequent pole flux switching machine (SPMCPFSM). Electric machines, especially flux switching machines (FSMs), are accurately modeled using numerical-based finite element analysis (FEA) tools; however, despite of expensive hardware setup, repeated iterative process, complex stator design and permanent magnet (PM) non-linear behavior increases computational time and complexity.

This paper reviews various alternate analytical methodologies for electromagnetic performance calculation. In above-mentioned analytical methodologies, no-load phase flux linkage is performed using LPMEC, magnetic co-energy for cogging torque, LE for magnetic flux density (MFD) components, i.e. radial and tangential and MST for instantaneous torque. Sub-domain model solves electromagnetic performance, i.e. MFD and torque behaviour.

The reviewed analytical methodologies are validated with globally accepted FEA using JMAG Commercial FEA Package v. 18.1 which shows good agreement with accuracy. In comparison of analytical methodologies, analysis reveals that sub-domain model not only get rid of multiples techniques for validation purpose but also provide better results by accounting influence of all machine parts which helps to reduce computational complexity, computational time and drive storage with overall accuracy of ∼99%. Furthermore, authors are confident to recommend sub-domain model for initial design stage of SPMCPFSM when higher accuracy and low computational cost are primal requirements.

The model is developed for high-speed brushless AC applications.

The SPMCPFSM enhances electromagnetic performance owing to segmented PMs configuration which makes it different than conventional designs. Moreover, developed analytical methodologies for SPMCPFSM reduce computational time compared with that of FEA.

The end-effects is a well-recognized phenomenon occurring in the linear induction motor (LIM) which makes the analysis and control of the LIM with good performance very difficult and can cause additional significant non-linearities in the model. So, the compensation of parameters uncertainties due to these effects in the control system is very necessary to get a robust speed control. The purpose of this paper is to propose a new technique of LIM end-effects estimation using the inverse rotor time constant tuning in order to compensate the flux orientation error in the indirect field-oriented control (IFOC) control law.

First, the dynamic model of the LIM taking into consideration the end-effects based on Duncan model is derived. Then, the IFOC for LIM speed control with end-effects compensation is derived. Finally, a new technique of LIM end-effects estimation is proposed based on the model reference adaptive system (MRAS) theory using the instantaneous active power and the estimated stator currents vector. These estimated currents are obtained through the solution of LIM state equations.

Simulations were carried out in MATLAB/SIMULINK to demonstrate the effectiveness and robustness of LIM speed control with the proposed MRAS inverse rotor time constant tuning to estimate end-effects value. The numerical validation results show that the proposed scheme permits the drive to achieve good dynamic performance, satisfactory for the estimated end-effects of the LIM model and robustness to uncertainties.

The end-effects causes a drop in the magnetizing, primary and the secondary inductance, requiring a more complex LIM control scheme. This paper presents a new approach of LIM end-effect estimation based on the online adaptation and tuning of the LIM inductances. The proposed scheme use the inverse rotor time constant tuning for end-effects correction in LIM vector control block.

The major disadvantage of the field-oriented control (FOC) scheme of induction motors is its dependency on motor parameter variations because of the temperature rise. Among the motor parameters, rotor resistance is a parameter that can degrade the robustness of FOC scheme. An inaccurate setting of the rotor resistance in the slip frequency may result in undesirable cross coupling and performance degradation. To overcome this disadvantage, the purpose of this paper is to propose a model reference adaptive system (MRAS) rotor time constant tuning to improve the induction motor drive performance and to compensate the flux orientation error in vector control law.

First, the dynamic model and the indirect field-oriented control of induction motor are derived. Then, an inverse rotor time constant tuning is proposed based on MRAS theory where a new adaptation signal formulation is used as reference model, and the estimated stator currents obtained from induction motors (IM) state space resolution is used in the adaptive model.

The effectiveness and robustness of IM speed control with the proposed MRAS inverse rotor time constant estimator is verified through MATrix LABoratory/Simulink model simulation and laboratory experimental results. The simulation and experimental results show good transient drive performances, satisfactory for rotor resistance estimation and robustness with regard to uncertainties and load torque disturbance.

This paper presents an online tuning of the inverse rotor time constant using a new adaptation signal MRAS model. The proposed estimator is proved to guarantee the stability for different operating conditions, especially in very low/zero speed region and heavy load torque. The stability analysis of the proposed estimation procedure is also demonstrated.

The purpose of this paper is to show that constructing magnetic equivalent circuits (MECs) for simulating accelerator magnets is possible by defining a three-port magnetic element for modelling the T-shape field distribution, where the flux leaves the yoke and enters the aperture.

A linear three-port magnetic element is extracted from an analytical field solution and can be represented by a number of two-port elements. Its nonlinear counterpart is obtained as a combination of the corresponding nonlinear two-port elements. An improved nonlinear three-port element is developed on the basis of an embedded nonlinear one-dimensional finite element model.

The T-shaped field distribution comes together with a complicated interplay between the saturation of the ferromagnetic yoke parts and flux leaking to the aperture. This is more accurately modelled by the improved nonlinear three-port magnetic element.

MECs have a limited validity range, especially for configurations where a high saturation level and fringing flux effects coexist.

The results of the paper appeal to be careful with applying nonlinear MECs for simulating bending magnets.

A new nonlinear three-port magnetic element for ferromagnetic yoke parts with T-shaped flux distribution has been developed.

A Web3 lifeworld consists of an imaginary and a shared commons. A Web3 imaginary is shown to include most, if not all, of the following: (i) the stated goal or purpose of the community, (ii) the behavioral norms, (iii) the lore or history, and (iv) what is opposed. A typical Web3 commons is shown to involve three elements: hash (technical), bash (social) and cash (finance). When changes come in Web3, the response is enacted using an available lever from the hash, bash, cash model of decentralized organization, but the response must not be in friction with the community’s imaginary, or it will most likely grind to a halt. Effective response to change becomes part of the Web3 lifeworld’s toolkit.

Australian cricket has traditionally been an exemplar of hyper-masculine sporting conservatism. However, cricket, as with a number of Australian sports, has recently introduced an elite women's league. Despite growth in participation and funding of women's cricket, it remains poorly understood at the elite level and particularly its fans. Drawing on the concept of gender-bland sexism (Musto et al., 2017), we investigate differences in fan engagement and perceptions of men's and women's cricket matches. Through a case study of Australian Women's Big Bash cricket team the ‘Sydney Sixers’, this chapter explores how women's cricket was experienced on match-day by fans, as well as perceptions of the value and quality of attending women's professional cricket. We first undertook participant observation at matches to understand how women's cricket was delivered, experienced and engaged with by fans. These observations informed a survey which was distributed to club members. Our findings suggest that there continue to be noticeable differences in the presentation of women's matches when compared to their male equivalents, providing evidence for the presence of gender-bland sexism in areas other than sports media.

The current interest in Industrial Relations has created a demand for training in the skills of negotiation; the training world has responded to this demand with an astonishing spectrum of activity. Old human relations case studies have been lovingly dusted and refurbished, role‐playing has come back into its own and HMSO has made a creditable little fortune for the tax‐payer from its timely booklets at 15p each. All sorts of people, including some of my legal acquaintances who this time last year had never even heard of industry, let alone industrial relations, have been sucked in to meet the demand. This article testifies to my own involvement, although initially without real conviction. Working in the industrial relations field with the late Bill Allen had convinced me that nothing short of major cultural change could significantly improve the negotiating climate in Britain. But this sounds like stealthy autobiography and I shall spare you the tediousness of my history and thinking in this area. Instead, let me indulge in that most deplorable characteristic of British industrial relations practice and do some bashing of the other side. The current crop of industrial relations and negotiating skills training courses gives plenty of scope for such bashing. Of the many practices which merit criticism, two stand out as being irresistibly obnoxious.

This study aims to investigate the effect of seasonality caused by fasting as a religious practice on trading activity.

The authors use an unbiased sample of daily trading by individuals and institutions on the Boursa Kuwait. The authors use panel data on trading activities and Tobit regression models to examine the effect of Muslims’ religious practice of fasting during the holy month of Ramadan on trading behavior.

The authors find that during the holy month of Ramadan, Muslims’ religious practice of fasting leads to a decline in the frequency of both overall stock market trading and the ratio of individual trading volume to total trading volume. The authors find a significant decrease in individual buy-side trading as a proportion of total trading volume and simultaneously a significant increase in institutional buy-side trading.

This study’s findings have important implications for the main players in stock markets of countries with a Muslim majority. Market-makers should be aware of the significant increase in the proportion of institutional buy-side trading volume to total trading volume to minimize the cost of trading with better-informed traders (adverse selection).

To the best of the authors’ knowledge, this is the first study that investigates individuals’ trading activity during Ramadan.

To describe the development of and experience with a system that tracks the position of knocks and taps atop a large sheet of glass for use as an inexpensive retrofit that can make large windows into interactive interfaces.

The structural‐acoustic wavefront coming from the impact is simultaneously recorded by four contact piezoelectric pickups mounted near the sheet's corners. A digital signal processor extracts relevant characteristics from these signals, such as amplitudes, frequency components, and differential timings, which are used to estimate the location of the hit and derive other parameters, including a degree of confidence in the position accuracy, the strike intensity and the nature of each hit (e.g. knuckle knock, metal tap, or fist bang – our system responds to any kind of impact). A set of heuristically‐guided rules are employed to compare the waveforms recorded by different sensors and determine the differential timing.

Across sensitive areas ranging up to 2×2 m, we have obtained position resolutions of σ=2.5 cm for 1/4 in. tempered glass and σ=3‐4 cm for 1 cm thick shatterproof glass. Our system delivers 65 ms latency, hence is essentially real time. The system has been installed in several public settings, and has proven to be very robust.

Suggestions are given for doing everything in software and not using the DSP. Analytical compensation of the dispersion would probably yield better precision but require more computation time.

As this system requires only simple hardware, it needs no special adaptation of the glass pane, and allows all tracking transducers to be mounted on the inner surface, hence it is quite easy and inexpensive to deploy as a retrofit to existing windows. This opens many applications, such as an interactive storefront, with content controlled by knocks on the display window, an interactive museum display case, or a vending machine where one can select by tapping directly above the desired item.

As large displays become less costly and more common, systems like these can make them interactive. This paper details our approach.