Electronics

Design Considerations in $hbox{MgB}_{2}$-Based Superconducting Coils for Use in Saturated-Core Fault Current Limiters
Saturated-core fault current limiters (FCLs) are devices that have many applications and potential for use within power networks. At a commercial scale, these devices require high H-field magnets to saturate the steel core, which can typically only be achieved through the use of superconducting coils. Here, we present several challenges that arise in the application of superconducting coils in ...


Research on a Superconducting Magnetic Flux Concentrator for a GMI-Based Mixed Sensor
A magnetic concentrator (MC) is often used to increase the performance of traditional magnetic sensors. A superconducting MC has been proven to be high powered when integrated with a field sensor. Such concentrators are often designed as a square loop shape with a narrow constriction. When an external field is applied, a superconducting current will be induced that flows in the loop. The self-f...
Thermodynamic analysis of single- and double-effect absorption refrigeration systems for cooling ethanol fermentation process
Alcoholic fermentation is one of the most important stages in industrial ethanol production process, involving a biochemical and exothermic reaction. Sometimes cooling towers are not capable of supplying a cold utility with a temperature low enough to maintain the fermentative medium temperature in a desirable range. Absorption Refrigeration Systems (ARS) appears to be a good alternative to obt...


Optimization of the reserve-type distributor for r410a air conditioner
Mal-distribution of refrigerant in a cross-flow type evaporator with parallel paths is very important, which can lead to a loss of heat exchanger capacity to 25%. Distributors are used to balance the two-phase refrigerant distributions in each path. Apart from the structural factors, there are other factors influencing the performance of distributor greatly. In this paper, influences of several...
A novel concept for derating of transformer under unbalance voltage in the presence of non linear load by 3-D finite element method
Unbalanced supply voltage and non-linear loads have become significant consideration in the designing transformers. This condition results in devastating effects such as high loss, early damage of insulation and premature failure of the transformers. For proper operation of transformers, capacity of transformer should be reduced. This paper presents a novel concept for mixed derating of distrib...


Self-resonant frequencies of air-core single-layer solenoid coils calculated by a simple method
Single-layer air-core solenoid coils are important components in many fields of electrical engineering, such as, high- frequency applications, air-core transformers, inductive sensors and wireless power transfer. The calculation of its self-resonant frequencies is of primary interest in many different situations. In these components, the validity of lumped element models is critical, since even...
Compressed sensing-based unequal error protection by linear codes
In many wireless communication systems, data can be divided into different importance levels. For these systems, unequal error protection (UEP) techniques are used to ensure lower bit error rate for the more important classes. Moreover, if the precise characteristics of the channel are known, UEP can be used to correctly recover the more important classes even under severe receiving conditions....

Optimal rate allocation for speech enhancement using remote power-constrained wireless microphones
The problem of speech enhancement is considered in an interference environment, typical to applications like hands-free voice communication and multi-party conferencing. In the proposed system, a directional microphone placed at each interference is used to estimate the power spectral density (PSD) of the interference and the quantised PSD estimate is transmitted over a wireless link to an omni...
Multiresolution wavelet-based QRS complex detection algorithm suited to several abnormal morphologies
The electrocardiogram (ECG) signal is considered as one of the most important tools in clinical practice in order to assess the cardiac status of patients. In this study, an improved QRS (Q wave, R wave, S wave) complex detection algorithm is proposed based on the multiresolution wavelet analysis. In the first step, high frequency noise and baseline wander can be distinguished from ECG data bas...

Robust compressed sensing with bounded and structured uncertainties
The robust compressed sensing problem subject to a bounded and structured perturbation in the sensing matrix is solved in two steps. The alternating direction method of multipliers (ADMM) is first applied to obtain a robust support set. Unlike the existing robust signal recovery solutions, the proposed optimisation problem is convex. The ADMM algorithm that every subproblem has a global minimum...
Quantised innovation Kalman filter: performance analysis and design of quantised level
This study provides a performance analysis for the quantised innovation Kalman filter (QIKF). The covariance matrix of the estimation error is analysed with the correlation between the measurement error and the quantising error. By taking the quantisation errors as a random perturbation in the observation system, an equivalent state-observation system is obtained. Accordingly, the QIKF for the ...

Compressed sensing with partial support information: coherence-based performance guarantees and alternative direction method of multiplier reconstruction algorithm
The recently introduced theory of compressed sensing (CS) enables the recovery of sparse or compressible signals from a small set of non-adaptive measurements, and furthermore, it holds promise for substantially improving the performance by leveraging more signal structures that go beyond simple sparsity. In this study, the authors study the weighted l1 minimisation problem for CS reconstructio...
Improved higher order robust distributions based on compressive sensing reconstruction
A general form of compressive sensing (CS)-based higher order time-frequency distributions (TFDs) is proposed. Non-linear time-varying spectrum analysis requires higher order TFDs, but they cannot produce efficient result in the presence of strong noisy pulses. Consequently, the time-frequency analysis needs to be combined with the L-statistics. When applied to the higher order local auto-corre...
Amplitude-phase discontinuity calibration for phased array radar in varying jamming environment
The amplitude-and-phase error (APE) between phased array channels is notorious in radar signal processing. This error can cause an inaccurate estimate of unknown steering vector of the target echo signal and eventually result in amplitude-phase discontinuity of the phased array output. Thus, how to handle the APE is a meaningful problem, particularly for the varying jamming environment, of whic...
Optimal normalisation of prediction residual for predictive coding with random access
Linear prediction serves as a mathematical operation to estimate the future values of a discrete-time signal based on a linear function of previous samples. When applied to predictive coding of waveform such as speech and audio, a common issue that plagues compression performance is the non-stationary characteristics of prediction residuals around the starting point of the random access frames....