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This study investigated technologies related to a smart-card display and its wireless charging system, where the wireless receiver in the smart card receives not only the data but also the power required for the display circuitry. The goal of this research was to achieve the required energy transfer during the extremely short reading time when a person swipes his or her smart card. This paper describes the design considerations and the analysis procedures of the transmitter and receiver pair for an electronic paper (E-paper) display. A series of magnetic simulations as well as experimental tests were conducted to investigate the various design factors. The design considerations included the shape and effect of using ferromagnetic cores, the component design for frequency tuning, the geometric arrangements, and the number of turns of the coils. A novel design for power transmission is then proposed using a ferromagnetic core to enhance its energy efficiency. In experiments the transmitter unit prov...

The basic electrical characteristics of paper, mica and ceramic capacitors are compared. The interesting characteristics of the new high permittivity ceramics are discussed in detail with appropriate curves and tables. Apart from the reduction in size which is obvious due to the much higher permittivities shown by these ceramics, the large temperature coefficient exhibited by some of the ceramic bodies can be utilized for certain special applications. Experimental results of the performance of receivers under different temperature conditions in which paper capacitors have been substituted completely by the ceramics are presented. Conclusions are that ceramics can completely substitute paper capacitors with advantage. It has been sought to show that ceramics can be actually custom-built or made to the desired specifications of the circuit designer.This conclusion is particularly significant as the chances of obtaining the raw materials for the manufacture of paper capacitors indigenously are very r...

Fibre optics is still a new and developing industry. Because of its expected growth, some thought and planning must be given in educating those workers who will be needed to sustain this growth. This paper reviews the history of educational activities that parallelled (and contributed to) the introduction of fibre optic technology. It describes the educational experiences of the the first fibre optic workers and the evolution that has seen fibre optic instruction grow to become an integral part of the curriculum of many leading educational institutions. An array of educational opportunities are described which are suitable for the novice and for the advanced practitioner. Guidelines are presented for designing a fibre optic educational program.

Dispersion in optical fibres is an important characteristic of the fibre which determines the information carrying capacity and also the repeater spacing. In this paper, a unified discussion of pulse dispersion in multimode as well as single mode fibres is presented. A tutorial presentation of the various physical mechanisms of the broadening of a pulse during transmission through optical fibres and the methods to design fibres with minimum dispersion have been made.

This paper reports installation practice as applied for installation of fibre optic cables in Denmark as of 1985. The information given herein is based on datas provided by the long sections of optical lines installed by the Danish Posts and Telegraphs and by the Jutland Telephone Company.

This review paper briefly outlines the basic design considerations of single-mode fibres. It analyses the features of the different designs being used in the world today and summarizes the trends i...

This paper describes the principles and applications of interferometric optical fibre sensors. The basic physical phenomena in dual beam and multiple beam interferometers are briefly described together with the principles of phase detection. The interface between fibre optic interferometers and physical measurands is then considered and the fundamental limits on performance potential are identified. Both passive and active fibre optic components have an important bearing on the realisation of practical sensor systems and the implications of this are discussed in some detail. This is followed by some speculation as to the future trends and system concepts which are to be expected in the second generation of interferometric sensors.

A solid-state image intensifier consists basically of a photoconducting layer (PC) and an electroluminescent layer (EL) sandwiched together between two transparent conducting electrodes. When an ac field is applied to this sandwich, it is possible to obtain on the output EL layer, an intensified version of the optical image presented on the input PC surface. Several sandwich type solid-state image intensifiers (SSII) have been fabricated in our laboratory. The fabrication and characterisation of a PC-EL panel consisting of CdSSe(Cu) powder in polystyrene binder as PC layer and ZnS(Cu) in cynoethyl cellulose binder as EL layer are reported here.

The working principles and the operating characteristics of semiconductor lasers are described in a pedagogical manner with particular attention paid to their applications in optical fibre communications. For their use at the fibre-loss-minimum wavelength of 1.55 μm, semiconductor lasers shoould oscillate in a single longitudinal mode. The techniques adopted for the single-frequency operation are briefly described. The performance requirements of semiconductor lasers for coherent fibre-optic communication systems are discussed and the use of an external-cavity semiconductor laser for such systems is mentioned.

The operating characteristics of distributed feedback (DFB) InGaAsP lasers are reviewed from the point of view of their applications in optical communication systems. The wavelengths and the threshold gains of the allowed longitudinal modes of a DFB laser are obtained using the coupled-wave theory after incorporating both the facet reflections and the grating-induced distributed feedback. The experimental results are presented for 1.55 μm DFB semiconductor lasers. In particular, we discuss the temperature dependence of the threshold current and the emission wavelength, the modulation response, the frequency chirp, and the linewidth of the single longitudinal mode selected by the DFB mechanism.

The ray optics for use in fibre communication systems is developed starting from the Maupertuis' law of stationary action, which is termed “modal-ray optics” and is different from the much better known Hamilton's optics based on the dynamical law of action. The reader is cautioned not to confuse the two different physical bases, although one may find a close similarity between the resulting formulae. The basic concepts of modal ray do not contain the time describing the dynamical motion of light such as the motion of a light pulse, so that the dynamical properties, if necessary, are discussed in the spectral domain or the complex space coordinates. The quantization rule by Keller is used to determine the modal states of the ray fields, which is well suited to the modal-ray optics. It is shown that for certain specific fibres, the theory provides the well-known results deduced from other theories. The polarization of light is also described by means of the above mentioned optics.

Some fibre fabrication techniques commonly used for the production of optical telecommunication fibres are presented and described by means of their basic mechanisms. The fabrication techniques considered here are the rod-in-tube method, double-crucible method, IVD-, OVD-, CVD-, MCVD-, PMCVD-, PCVD-, POD-, and VAD-method. A comparison summarizes the present performance of those techniques used for high quality fibre fabrication.

The main state-of-the-art techniques for the evaluation of chromatic dispersion in single-mode fibres are reviewed, and methods based on nearfield, farfield, and/or spot-size measurements are mentioned. A mathematical development for the estimation of pulse shapes (for arbitrary input pulses) is presented together with an analytical formula for the Gaussian pulse case.

Opto-electronics technology based on optical fibres, semiconductor lasers and detectors, micro-optic components and opto-electronic integrated circuits will be the technology for the next era of the information age. A perspective of the future direction of research and development as well as the significance of such new opto-electronic technological progress in the information age is presented.

The following problems are reviewed: mutual influence among imperfect joints on loss and on bandwidth; index-profile concatenation phenomena, both from a deterministic approach (i e, assuming that successive fibres can be selected on purpose) and from a statistical one (random sequences of fibres). Finally, we present previously unpublished results on WDM systems on concatenated fibres. The probability of having at least one optical channel which is severely band-width-limited is shown to be high.

A tutorial introduction to the fused-tapered single-mode optical fibre coupler is presented. It is shown that the properties of the coupler can be deduced from fundamental physical arguments without reference to the detailed internal construction of the component. Some of the important experimental properties are discussed and a detailed theoretical model is discussed.

Existing geometric-optical techniques for exciting and analysing modes in a multimode optical fibre have proved insufficient in treating single fibre modes. We discuss the principle of wave-optical methods using computer-generated matched-filter holograms for the synthesis and analysis of arbitrary fibre fields in terms of suitable orthogonal functions, and report on progresses in the making of such filters. Our techniques could gain importance in evaluating the speckle pattern at the end-face of multimode fibre sensors.

We have presented electromagnetic analyses of a number of optical waveguides used in integrated optical devices. The attempt in each case has been to consider a simple refractive index distribution and bring out most of the important propagation characteristics of the waveguide. Some of the analyses will be quite general in nature e g, the study of leaky modes, the use of the recently-developed matrix method for determining the propagation characteristics of optical waveguides, the application of perturbation method for the analysis of non-separable profiles etc and would be applicable to optical fibres also.

Intensity and phase modulated multimode fibre-optic sensors are described. Cross-talk between two multimode fibers has been used to develop sensors for the detection of oil films on the surface of water and for analog measurements of liquid levels and temperatures. Frustrated total reflection at the end of an optical fibre is used for detecting air or gas bubbles and also for measuring refractive index and turbidity of liquids. Development of interferometer in the form of multimode Fibre Fabry-Perot sensor ‘FFP’ is described. The versatility of multimode FFP sensors is demonstrated and the advantages of multimode technology in fibre-optic interferometry are indicated.

Several prior studies reported that the header compression (HC) achieves several gains like bandwidth savings, faster response time and better reliability. A few other studies reported about loss due to HC. In this short paper, we introduce a single parameter named "power" to measure the gains of HC. We also introduce another single parameter as "effective power" to measure both the gains and the loss of HC. We find that the performance measurement by such single parameters gives more intuitive analysis and understanding of functions of HC.

This paper mainly studies the financial data management method and edge computing platform based on intelligent edge computing and big computing. This paper first introduces the theoretical basis o...

This paper mainly studies the numerical simulation of the force process of the runner blades in the transient process of the pump-turbine. In this paper, dynamic simulation technology is used to ca...

In this paper, the Radiating element of a patch antenna for energy harvesting application was fabricated using the graphene ink-based screen printed method. Wax-coated paper and polyester were inve...

This paper presents a detailed review of the design aspects and performance analysis of high-frequency inverters used in inductive power transfer application (IPT) for electric vehicles. The paper’...

The impact of phase noise on the short-term frequency stability (i.e. the Allan deviation with smaller averaging time) of a frequency source has been discussed in detail in the paper. The paper als...

Cognitive Radar is a recently presented research topic, in which most efforts has been done for its conceptual description and the adaptive waveform design feature of these radars, while other aspects of additivity for optimum performance of cognitive radars has been ignored. In this paper, a framework for adaptive time resource management in Cognitive Radars is proposed. The main purpose of this paper is proposing an algorithm for time resource management, with incorporation of adaptive waveform design capability of cognitive radars, to enhance the radar performance for an efficient time resource usage. After developing the equations of radar time resource management using adaptive waveform design, an implementable algorithm is proposed for this purpose and its performance is simulated and analysed. The results show that the proposed algorithm resulted in more efficient time resource management compared to the existing ones.

The paper proposes the analysis of power supply system efficiency, including power supply reliability, power quality, and the quality of technological connections to power networks. In the paper, t...

This paper presents an interval type-2 fuzzy logic (IT2FL) controlled single-phase enhanced power quality-based photovoltaic distributed generation (PVDG) system. The objective of this paper is to ...

In this paper, the stability analysis and stabilization of time-delay nonlinear systems represented by a Takagi–Sugeno fuzzy model are investigated. Combining with a recently developed integral inequality, relaxed delay-dependent stability conditions are derived by means of linear matrix inequalities. To obtain the further relaxed stability criteria, the membership-function-dependent method is applied via the piecewise membership functions (PMFs) and some slack variables. The PMFs are selected to approximate the membership functions (MFs), and then the characteristics of the MFs are taken into consideration adequately. Under the imperfect premise matching design scheme, this paper also proposes a flexible fuzzy controller design strategy that the fuzzy controllers do not employ the identical MFs and the number of rules as the fuzzy models. Finally, this proposed approach is tested successfully and its effectiveness is validated by the simulation examples.

Routh Approximation is believed to witness tremendous usage in deriving the reduced models from their higher equivalents. Order reduction is a critical field of interest for researchers or control engineers dealing with practical and physical systems of higher order. Reason for the popularity of Routh Approximation among other reduction methodologies is its strength of computational simplicity, ease of access and the promise to retain the model stability. This paper accomplishes a survey of the available Routh Approximation algorithms in their varied configuration since five decades. Last survey report based on Routh Approximation was cited in late seventies as discussed in the paper. One prime reason for the outcome of this paper is the problem met by the authors during their own work for analysing varied configuration of Routh Approximation for order reduction. Many times, the arrangement, stated or performed, seemed to be already in existence. Thus, the paper would be helpful to the researchers...

This paper primarily focuses on an investigative study on allocating Flexible AC transmission system (FACTS) devices on radial distribution systems. The FACTS device that is used in this paper is static var compensator (SVC). In this paper, SVC is placed on each bus except substation bus and study the results to find the best location for allocation. A design of SVC was done by fixed reactance method. The total power loss of network and voltage of nodes have been analyzed for each allocation and the sequences of each implementation have been compared to find the best location of SVC. The proposed algorithm has been executed on IEEE 33-bus and 69-bus standard test systems.

This paper studies the combination of a centre-weighted median filter with block matching 3-D filtering for digital images with mixed impulsive and Gaussian noise. The proposed combined filter has an extended application range with respect to both components. The work in the paper derives a simple formula for selecting the weight of the centre-weighted median filter. Adaptive weights are given for neighbourhoods 3 × 3 and wider as functions of the impulsive noise percentage and Gaussian noise strength. Simulation results confirm the effectiveness of the proposed combined filter.

In this paper, a scheme for the collection of potential energy from the movement of the human body has been presented. According to the analysis of the movement characteristics of the body parts, an energy conversion mechanism was designed to adapt to the characteristics of human body movement. According to the characteristics of output energy conversion mechanism, an energy collection circuit was designed to convert the weak pulse energy storage output using a body energy conversion mechanism to provide a stable energy source for low-power-consumption sensors. The experimental results showed the energy conversion efficiency of the energy collection system proposed in this paper to be 42%. It was able to collect about 2 mW of human lower legs motion energy, which can meet the daily needs of low-power sensors mounted on the human body.

Ferroresonance is one of the complex phenomena, which occurs in power network. This can create thermal and insulation problems in the power system equipments. It can also cause chaotic oscillations in the power network. The magnitude of the power system capacitor is one of the important factors that lead to ferroresonance in capacitor voltage transformers (CVTs).Thyristor controlled series capacitors (TCSCs) are applied for series compensation in the transmission line of power system. In normal operation, these equipments have capacitance magnitude up to three times of fixed capacitor such that the increased value of transmission line capacitor, which is one of the reasons for ferroresonance occurrence, is provided. This paper studies and investigates the effects of TCSCs on the ferroresonance in the CVTs. Because of nonlinear dynamics of ferroresonance, bifurcation theory is utilized in this paper. Using this theory, variation of system parameters that cause chaotic ferroresonant oscillations can...

This paper presents an energy-efficient Modified Distance Vector Hop algorithm using Teaching–Learning-Based Optimization, viz. MDV-TLBO, which is range-free, distributed localization algorithm for wireless sensor network (WSN). In the proposed algorithm, the hop size of anchor node is modified by adding correction factor. The concept of collinearity is introduced in this paper to reduce location errors caused by anchor nodes which are collinear. TLBO is used to enhance the localization accuracy, which is parameter-free, efficient optimization technique. Target nodes estimate their final coordinates after location upgradation procedure. In MDV-TLBO, anchor nodes communicate only one time with target nodes to broadcast their location. Hop size modification, optimal selection of anchor nodes, location optimization, and location upgradation are done at target node level, resulting considerable reduction in communication between nodes, due to which energy consumption of the nodes has been significantl...

Multiple-input–multiple-output (MIMO) systems have emerged as a promising solution to provide high data rate wireless services in a rich scattering environment. This paper deals with the performance analysis of the MIMO system in correlated non-uniform phase distributed Nakagami-m channel with linear receiver. Authors have considered spatial diversity scheme i.e, vertical bell laboratories layered space-time (V-BLAST) systems in correlated MIMO Nakagami-m fading channels with equal power distribution among the transmitter side antennas. Also, they consider that the channel state information (CSI) is available only at the receiver. The paper presents a detailed analysis of the channel capacity in correlated and uncorrelated channel condition and validated the result with appropriate mathematical model. The effect of Doppler shift and Nakagami-m fading parameter m on the channel ergodic and outage capacity has been analyzed here.

This paper shows the experimental results obtained by applying the classifier parallel scheme of decision tables (ParalTabs) to detection of genes in individuals associated with laryngeal cancer11 This paper is an extended version of two conference paper that appeared in [1] and [2]. The key additions of this journal version are as follows. First, in Section 3 we use a different way of how to implement the ParalTabs algorithm, using a set of processes instead of threads. Second, in Section 4 we use the same transformation of data used in previous work [2], but the size of data in this paper is different. Finally, this paper contains new experimental results in Section 4, one of this is using ParalTabs for searching genetic Q3 Q2 markers of laryngeal cancer, which is different from those shown in the paper [2].. The experiments are performed by analyzing a chromosomal database of laryngeal cancer which has the International System for Human Cytogenetic Nomenclature format. ParalTabs is an implement...

This paper explores the use of combination of flexible alternating current transmission system (FACTS) devices, demand response (DR) programs, and generation redispatch (GR) in short-term congestion management as well as minimization of operation costs under contingency conditions in power systems. To achieve this, a multi-stage market clearing procedure is formulated. At the first stage, the market is cleared based on generation cost minimization, without considering network constraints. Market clearing formulation for the second stage is developed considering congestion and generation costs, in which FACTS device (Thyristor Controlled Series Capacitor) and DR programs (Direct Load Control besides Time-Of-Use) are optimally coordinated with GR in the presence of network constrains, to manage the congestion at minimum costs. In addition, to make conditions more realistic, the operational conditions spanning for a year (four seasons, day by day) are considered in this study. Finally, the paper prio...

This paper presents the numerical study of a new schematic for extracting marine energy through offshore wave energy harvesting and analyzes the design factors as well as environmental factors that create deviations in the energy efficiency. Though the device has some similarities to a traditional Backward Bent Duct Buoy, this invention is double-chambered and the whole power take-off set-up remains inside the device. It is a floating-type wave energy converter with a buoyancy material which can produce electric power from the movement of air inside the device from one chamber to another without interacting with the outside atmosphere which ensures device longevity and better performance of the system in rough ocean weather and normal weather alike. As the device has two chambers opposite to one another it can make efficient use of waves out of phase. The paper includes MATLAB simulated results for mechanical power obtainable from a bidirectional wind turbine inside the device.

Epilepsy is a critical brain disease which occurs primarily based on changes or connectivity issues between two neurons. Electroencephalography (EEG) is an efficient modality for capturing brain signals with respect to stimuli. Total variation (TV) is an energy based feature which helps to discriminate epilepsy from normal pattern. This paper proposes an efficient epileptic detection system based on TV model. Existing methods use single feature for classification, whereas, combination of multiple relevant features helps for better understanding of epilepsy. This paper also discusses combined multi feature model with TV for efficient detection and classification of EEG signal subbands (gamma, beta, alpha, theta, and delta) using support vector machine. Results show 100% delta band based classification accuracy for combination of features such as TV and sample entropy. This research also shows that combination of multi features such as, Shannon, spectral, TV, and linear predictor coefficient gives g...

A novel single-phase 29-level asymmetrical switched-diode multilevel inverter (MLI) topology is presented in this paper with a reduced number of components. The developed topology can able to generate a maximum of 29-levels of output voltage using unequal DC sources. The basic 15-level MLI is developed and then further developed to 29-levels. The proposed topology reduces the circuit components, size and cost of the system. Apart from the several benefits of MLIs, reliability and accuracy plays a vital role because of the existence of more components count to reduce THD value. This can be considered as a major challenge employed to boost reliability without altering the best THD value. Various parameters are realized for both basic 15-level and the proposed 29-level switched-diode MLIs like total standing voltage (TSV), power loss, efficiency and cost function (CF). As the proposed MLI is undergone in dynamic load variations, the experimental results show the variations from R-load to L-load and L-load to R-load and it is found that the inverter is found to be stable throughout its operation. Experimental THD is represented, which is similar to the simulation THD which is under IEEE standards. TSV and cost factor of the proposed MLI is determined and is compared with several existing topologies and is observed to be cost-effective. A precise comparison is made on various parameters using graphical depiction. . The simulation for the proposed topology is done in MATLAB/Simulink and the experimental verification is done using the hardware prototype model under several conditions.