Showing papers in "Iete Journal of Research in 2015"
TL;DR: This paper demonstrates the design of reversible binary to grey and grey to binary code converter based on Feynman gate using QCA for the first time and established the functional efficiency of the circuits.
Abstract: Quantum dot-cellular automata (QCA) is an emerging nanotechnological archetype and has widespread applications in designing nanoscale reversible circuit for nanocomputing The low power consumption, faster operating speed, and low circuit area of QCA pledge the energy efficient design of logic circuit having high device complexity This paper demonstrates the design of reversible binary to grey and grey to binary code converter based on Feynman gate using QCA for the first time Both the proposed reversible code converter circuits have quantum cost as 2 The conversion of binary to grey code is achieved with only one garbage value and the grey to binary code conversion is achieved without any garbage value The proposed Feynman gate circuit required only 38,880 nm2 areas and three clocking zones The reversible binary to grey circuit required only 92,664 nm2 areas and three clocking zones whereas the reversible grey to binary circuit required only 139,968 nm2 areas and four clocking zones The pro
56 citations
TL;DR: A new meta-heuristic search algorithm, called Cuckoo Search (CS) is applied which is inspired by the natural behaviour of cuckoo species including the Lévy flight behaviour of some birds and fruit flies to obtain stable reduced-order model of higher order linear time invariant continuous systems.
Abstract: In this paper, a novel method is presented to obtain stable reduced-order model of higher order linear time invariant continuous systems using optimization technique. In order to perform optimization, a new meta-heuristic search algorithm, called Cuckoo Search (CS) is applied which is inspired by the natural behaviour of cuckoo species including the Levy flight behaviour of some birds and fruit flies. The effectiveness of the proposed method is supported by some numerical examples of single input single output (SISO) systems and the results are compared with other well-known methods available in the literature in terms of most popular performance indices like integral square error, integral absolute error, and integral time absolute error. The method is extended for multi input multi output (MIMO) systems also.
42 citations
TL;DR: A wireless sensor network that provides real-time monitoring of temperature, humidity and soil moisture of a greenhouse and an automated control system for managing these micro-climate parameters is developed to optimize the parameters and use of water.
Abstract: A greenhouse is an enclosed structure that provides micro-climate for the plant growth. This paper presents the design of a wireless sensor network that provides real-time monitoring of temperature, humidity and soil moisture of a greenhouse. An automated control system for managing these micro-climate parameters is developed to optimize the parameters and use of water. The sensor node developed handles the data from the sensors and triggers actuators based on the threshold algorithm programmed into the microcontroller. The gateway receives the sensor data and control information through Zigbee and transmits the data to the web application for remote monitoring. The monitor software provides network view with nodes and their information. Information management system is also designed to monitor the data at any required time.
42 citations
TL;DR: The experimental results reveal that the proposed method can be used as an effective tool for detection of heart muscle damage or MI automatically.
Abstract: In this work, an approach for heart muscle damage detection from echocardiography sequences is proposed. To exemplify the approach, a system is presented which involves image denoising and enhancement and segmentation of the left ventricle (LV) for extracting the heart wall boundaries. Using the heart wall boundaries global LV parameters are calculated followed by statistical pattern recognition and classification to identify the heart muscle damage or myocardial ischemia (MI). The performance of this algorithm is assessed in 60 real patient data with both normal and abnormal conditions. The experimental results reveal that the proposed method can be used as an effective tool for detection of heart muscle damage or MI automatically.
40 citations
TL;DR: In this paper, a robust controller based on backstepping strategy is designed in order to ensure globally asymptotically stabilisation for a particular class of second-order nonlinear systems.
Abstract: This paper addresses the nonlinear control design problem for a state-coupled two-tank liquid level system. For this system's dynamics, motivated by a desire to provide precise and economic liquid level control, a new output feedback control scheme is developed. In the proposed approach, a robust controller based on backstepping strategy is designed in order to ensure globally asymptotically stabilisation for a particular class of second-order nonlinear systems. Moreover, a model-based backstepping controller combined with a high gain observer is designed for the two-tank, liquid level system. Only one sensor is available to measure the liquid level in the bottom tank and the other process's state is assumed unavailable. The observer converges in a finite time and leads to good estimate of the liquid level in the top tank as well as a good track of the liquid level in the bottom tank with the reference trajectory. To highlight the efficiency and applicability of the proposed control scheme, a comp...
34 citations
TL;DR: In this article, a design scheme is proposed for fractional-order PI controller based on gain and phase margins for controlling the mean arterial blood pressure (MABP), which can work well in uncertain operating environment, and also show good disturbance rejection.
Abstract: Mean arterial blood pressure (MABP) is one of the most important clinical parameters which is required to be controlled very accurately. Therefore, it is very essential to have an efficient and precise control strategy for regulating the MABP in various clinical conditions, which can work well in uncertain operating environment, and also show good disturbance rejection. Although the fractional-order control scheme has evolved as a strong control strategy in recent times, the design techniques available in the literature are mathematically very complex and hence limit the usage of fractional-order controllers. Moreover, it is observed that the gain and phase margin based techniques that exist in the literature for integer order systems are not completely applicable to the fractional-order systems. Therefore, in this paper, a design scheme is proposed for fractional-order PI controller based on gain and phase margins for controlling the MABP. The beauty of the proposed technique is that the controll...
30 citations
TL;DR: In this article, a proportional integral (PI) control algorithm was proposed to adjust pitch angle of doubly fed induction generator (DFIG)-based wind turbine integrated with two-area-interconnected power system.
Abstract: The impact of wind power with higher size of penetration becomes significant for frequency control problem due to its inconsistent nature and lack of frequency support from the wind turbine units. The frequency can be managed using enhanced control of inertia and droop characteristics. However, at very low and high speeds, the adjustment of pitch angle of wind turbine is necessary so that the aerodynamic power produced remains within the designed limits. This paper discloses the design of proportional integral (PI) control algorithm to adjust pitch angle of doubly fed induction generator (DFIG)-based wind turbine (WT) integrated with two-area-interconnected power system. Here, a heuristic gravitational search algorithm (GSA) is employed to optimize the gains of PI controllers used for pitch angle adjustment and governor speed control of wind turbine, frequency regulation, and tie-line power flow control. The influence of optimal gains by GSA is compared with genetic algorithm (GA) and ant colony o...
29 citations
TL;DR: Simulation results show that the proposed technique outperforms both HEED and UCAPN protocols and generates a scalable and feasible energy-efficient routing technique for radially optimized zone-divided energy-aware WSN.
Abstract: The problems of hot spot and energy consumption of nodes in wireless sensor networks (WSNs) have been tackled by the adoption of hybrid energy efficient distributed (HEED) and unequal clustering algorithm to prolong the network lifetime (UCAPN) protocols. These have involved the implementation of unequally sized clusters that are based on the distance of cluster head (CH) from the base station (BS). The BS partitions the network area into several radially divided zones depending on the distance from centre of the field and CHs are independently selected in each zone. Clustering, on the other hand, controls how data are transmitted and allows for aggregation in the clusters. However, whereas these topologies have been able to improve network life time, the problem of network void still persists. To address this, a radially optimized zone-divided energy-aware WSN protocol using bat algorithm is proposed. This protocol considers not only the distance from the BS, but also the angle at which the WSN d...
28 citations
TL;DR: A modified CHI feature selection approach which is called term frequency and distribution based CHI to overcome weaknesses of Chi-square statistics and improve the classic CHI with maximum term frequency.
Abstract: Text categorization (TC) becomes the key technology to find relevant and timely information from a volume of digital documents, and feature selection techniques are proposed to overcome the high dimensionality which causes the high computational complexity and low accuracy in TC tasks. Chi-square statistics (CHI) is one of the most efficient feature selection methods; however, it has two weaknesses. (1) It is document frequency based, and only counts whether the term occurs or not. Actually, high-frequency term occurring in few documents is often regarded as a discriminator in corpus. (2) It does not consider the term distribution. A term has more discriminating power for a specific category when its difference in degree of distribution is lower. In this paper, we propose a modified CHI feature selection approach which is called term frequency and distribution based CHI to overcome these weaknesses. We use sample variance to calculate the term distribution, and improve the classic CHI with maximum...
27 citations
TL;DR: In this article, an accurate and compact analytical model of mixed CNT bundle (MCB) is employed that takes into account the random distribution of CNTs having different diameters, and a multi-conductor transmission line model is presented for MCB, bundled SWCNT, and bundled MWCNT interconnects.
Abstract: This paper deals with an analysis of propagation delay in carbon nanotube (CNT) bundled interconnects under process-induced variations. An accurate and compact analytical model of mixed CNT bundle (MCB) is employed that takes into account the random distribution of CNTs having different diameters. Depending on the bundle configurations, a multi-conductor transmission line (MTL) model is presented for MCB, bundled SWCNT, and bundled MWCNT interconnects. The performance of CNT bundles is investigated under process-induced variations of temperature, metallic ratio, contact resistance, and bundle area. A driver-interconnect-load (DIL) system is used to perform the Monte Carlo simulations to analyze the impact of process-induced variations on propagation delay. It is observed that the MCB is more tolerant to the process variations for global interconnect lengths with respect to the bundled SWCNT and bundled MWCNT.
23 citations
TL;DR: A comparison of AnFIS, ANN, fuzzy-based approaches shows the superiority of proposed ANFIS overANN, fuzzy for change in frequency and tie-line power deviation in three area interconnected power system.
Abstract: In this paper, artificial neural network (ANN) and fuzzy-based adaptive neuro-fuzzy inference system (ANFIS) approach to automatic generation control of three unequal area hydro-thermal power systems has been introduced. The proposed ANFIS controller combines the advantages of fuzzy controller as well as quick response and adaptability nature of ANN. Area 1 and area 2 consist of thermal reheat power plant whereas area 3 consists of hydro power plant with electric governor. Performance evaluation is carried out by using ANN, fuzzy, and ANFIS control approaches. To enhance the performance of intelligent controller, sliding surface is included. The performances of the controllers are simulated using MATLAB/SIMULINK software. A comparison of ANFIS, ANN, fuzzy-based approaches shows the superiority of proposed ANFIS over ANN, fuzzy for change in frequency and tie-line power deviation in three area interconnected power system.
TL;DR: This paper aims at denoising the mammogram by the wavelet and the curvelet transform with a motive to investigate the role of the “embedded” thresholding algorithm.
Abstract: Mammogram is an easy and affordable means of diagnosis of breast cancer. Like other medical data, it is also affected by noise during acquisition. Therefore, it is a challenge for the researchers to denoise the mammograms for clear data extraction. This paper aims at denoising the mammogram by the wavelet and the curvelet transform with a motive to investigate the role of the “embedded” thresholding algorithm. As the thresholding technique is a key factor for the noise reduction, a comprehensive study on the employment of the different types of the thresholding techniques with the transforms have been presented methodically. A standard mammogram from the Mammographic Image Analysis Society database is supplemented with different types of noise and then denoised by the wavelet and the curvelet transforms using the three commonly used thresholding techniques to compare the denoising performance of the thresholding algorithms along with the transforms. This investigation renders a clear insight to th...
TL;DR: This paper focuses its attention on self co-articulation problem which has not been addressed before, and removes the hand movement during pause state along with the velocity features within the gestures to perform the gesture spotting more smoothly for the isolated gestures.
Abstract: Hand gesture recognition system can be a particularly challenging task because of the presence of several spatio-temporal variations like hand trembling, self co-articulation within a gesture, etc. during the segmentation stage. In this paper, we focus our attention on self co-articulation problem which has not been addressed before. With the addition of a new feature, i.e. removing the hand movement during pause state along with the velocity features within the gestures, we were able to perform the gesture spotting more smoothly for the isolated gestures. Moreover, a new set of novel features was added in the feature extraction stage: (1) number of self co-articulated stroke; (2) orientation of the self co-articulated strokes; (3) position of the hand; (4) distance between the start and end points of a gesture; and (5) ratio between the longest and shortest distances from centre. These features were fed to neural network classifier. The results of experimentation were carried out with 40 gestures...
TL;DR: In this paper, a comprehensive study on ambipolar leakage suppression in Ge n-channel Schottky barrier MOSFETs (Ge n-SB MOSFLETs) is presented, where underlap gate structure over drain-channel junction, in addition with dopant segregation (DS) to depin the Fermi level is employed.
Abstract: This work presents a comprehensive study on ambipolar leakage suppression in Ge n-channel Schottky barrier MOSFETs (Ge n-SB MOSFETs) Also, Fermi level pinning due to metal-induced gap states between the metal contact and semiconductor is another constraint in this device, which restricts the modulation of Schottky barrier height Here, we effectively suppress the ambipolar leakage by employing underlap gate structure over drain-channel junction, in addition with dopant segregation (DS) to depin the Fermi level We also investigate the influence of the DS layer doping, thickness, and temperature dependence of ambipolar behaviour using two-dimensional numerical device simulations
TL;DR: A novel automatic unsupervised feature selection method based on gravitational search algorithm, called AFSGSA (automatic feature selection using gravitational search algorithms), which requires no prior knowledge of the data to be classified and number of features to be selected.
Abstract: Feature selection is an optimization problem that selects the features that have minimum redundancy and maximum relevance to improve the efficiency of algorithms. In this paper, we have proposed a novel automatic unsupervised feature selection method based on gravitational search algorithm, called AFSGSA (automatic feature selection using gravitational search algorithm). In contrast to most of existing unsupervised feature selection techniques, the proposed AFSGSA requires no prior knowledge of the data to be classified and number of features to be selected. AFSGSA determines the optimal number of features of the data-set on the run. Statistical property of data-set is used to develop a novel threshold setting concept to refine the features. A novel fitness function is also proposed to make the search more efficient. The performance of AFSGSA has been compared with recently developed well-known feature selection techniques. The experimental results reveal the efficiency and efficacy of the propose...
TL;DR: The delightful results reveal that the secrecy performance achieves a greater level when the Nakagami-m fading is supposed on the main link due to the line of sight component.
Abstract: In the perspective of information-theoretical security, inspired by the heterogeneity between legal and illegal channels, we consider the physical layer secrecy performance of a novel system model with a single antenna employed for both the transmitter and legal receiver, in the presence of a multiple antennas passive eavesdropper over dissimilar fading channels, where the legal/illegal channels are subject to Rayleigh/Nakagami-m and Nakagami-m/Rayleigh fading, respectively. We assume that the eavesdropper employs either maximal-ratio combining or selection combining reception in order to benefit from space diversity. Specifically, the exact closed-form expressions of the probability of existence of secrecy capacity and the secrecy outage probability are derived by utilizing statistical characteristics of the signal-to-noise ratio. Moreover, the delightful results reveal that the secrecy performance achieves a greater level when the Nakagami-m fading is supposed on the main link due to the line of...
TL;DR: The simulation results show CRPSOWM outperforms FFA by achieving much greater reduction in side lobe level, improved directivity and much more improved first null beam width keeping the same value of hyper beam exponent.
Abstract: In this paper, swarm-based algorithms craziness particle swarm optimization with wavelet mutation (CRPSOWM) have been applied for the optimal design of hyper beamforming of linear antenna array. The conventional gradient based optimization techniques are not efficient and get trapped on local optima for such multimodal highly non-linear constrained hyper beamforming optimization problem. Thus, the above evolutionary technique has been adopted. CRPSOWM incorporates a new definition of swarm updating with the help of wavelet theory. Wavelet mutation enhances the CRPSO to explore the solution space more effectively compared to the other optimization methods as reported in firefly algorithm (FFA). Thus CRPSOWM is apparently free from getting trapped at local optima and premature convergence. The simulation results show CRPSOWM outperforms FFA by achieving much greater reduction in side lobe level, improved directivity and much more improved first null beam width keeping the same value of hyper beam ex...
TL;DR: In this article, a shuffled frog-leaping algorithm (SFLA) was used to find the optimal SVC damping controller parameters considering different loading conditions. And the proposed algorithm was implemented on a test system with different load conditions.
Abstract: There have been a variety of studies developed to design static Var compensator (SVC) to enhance damping of electromechanical oscillations in power systems. This paper presents a novel method towards an optimal designing of SVC damping controller using shuffled frog-leaping algorithm (SFLA). The optimal parameters of the SVC controller are obtained using SFLA considering different loading conditions. A time-domain objective function is minimized using SFLA to find the optimum controller parameters. The proposed algorithm is implemented on a test system with different loading conditions. The damping characteristics of the presented technique are compared with genetic algorithm (GA) and bacteria foraging optimization algorithm (BFOA) in tuning SVC controller. The comparative analysis demonstrates the superiority of the proposed method on a wide range of operating conditions.
TL;DR: In this article, the authors presented new methods based on fusion of Hilbert transform and high frequency resolution techniques (estimation of signal parameter by rotational invariance technique (ESPRIT), root multiple signal classification (root MUSIC)) to extract bearing defect frequencies of induction motor bearing faults using vibration signal.
Abstract: This paper presents new methods based on fusion of Hilbert transform and high frequency resolution techniques (estimation of signal parameter by rotational invariance technique (ESPRIT), root multiple signal classification (root MUSIC)) to extract bearing defect frequencies of induction motor bearing faults using vibration signal. Further sliding window concept is introduced to tackle abnormal conditions like load variation and supply frequency variation. It also proposes a decision based approach to classify the severity of bearing fault. A series of results shows that both sliding window Hilbert-ESPRIT and sliding window Hilbert-root MUSIC are capable of extracting bearing defect frequencies accurately but, sliding window Hilbert-ESPRIT takes less computational time than the sliding window Hilbert-root MUSIC.
TL;DR: In this article, a probabilistic approach to determine the optimal location of a thyristor-controlled phase shifting transformer (TCPST) for enhancing the transient stability of power system is presented.
Abstract: Due to the large number of uncertainties in operation and planning of power system, it is appropriate to analyse the transient stability assessment as a stochastic problem. This paper presents the probabilistic approach to determine the optimal location of thyristor-controlled phase shifting transformer (TCPST) for enhancing the transient stability of power system. TCPSTs are the cost-effective means to ensure reliable and efficient power flow control in overloaded transmission lines. This feature leads to reduction of the rotor angle separation of synchronous generators during disturbance occurrence which improves transient stability of the system. To select the optimal location of the TCPSTs, the analysis of angular separation of rotors of generators is calculated by considering the probabilistic factors. The Western-System-Coordinating-Council (WSCC) 9-bus and Institute of Electrical and Electronics Engineers (IEEE) New-England 39 bus test systems were used to demonstrate the feasibility and ap...
TL;DR: In this article, a cascaded-integrator-combination (CIC) filter is proposed to approximate simultaneously both magnitude and group delay specifications by spreading of the delays in the comb stages.
Abstract: A new CIC filter architecture, i.e. CIC (cascaded-integrator-comb) FIR (finite impulse response) filter functions, designed by introducing spreading of the delays in the comb stages is presented here. The design forms of modified CIC filters that approximate simultaneously both magnitude and group delay specifications are given. The benefit of the novel filter class is demonstrated by a few example filter functions and their comparisons with existing classical CIC structures and one technique given in the literature. The effect of the compensation filter on the frequency response (reduction of the passband droop) is also shown. The novel cascaded-filter architecture has valuable benefits: wider passband range, higher insertion loss in stopband, as well as smaller values of integer coefficients of the impulse response.
TL;DR: This paper has extracted two types of geometrical features and a statistical crossing count feature with the help of horizontal, vertical, right diagonal, and left diagonal scan lines and centroid of the character to be recognized.
Abstract: This paper presents two novel geometrical feature extraction techniques for license plate (LP) characters recognition, written in English alphabets and numerals. A robust character recognition technique has to recognize different format, broken, and distorted characters by extracting invariant and discriminative character features. In this paper, we have extracted two types of geometrical features and a statistical crossing count feature with the help of horizontal, vertical, right diagonal, and left diagonal scan lines and centroid of the character to be recognized. For character recognition, we have used edit distance metric. The proposed technique can be enhanced to recognize any language scripts and is tested for Indian scripts. The proposed LP characters recognition technique is evaluated using 741 images of media-lab benchmark database, 49 images of Israeli vehicle LPs, and 110 images of proprietary Indian vehicle LPs having different environmental conditions and plate variations. The propos...
TL;DR: A new map-matching algorithm called street tracking algorithm (STA) is proposed to not only correct the position error, but also estimate the velocity and the heading of the navigation system.
Abstract: Most inertial navigation system/global positioning system (INS/GPS) navigation systems for vehicles estimate position, velocity, and heading information from the GPS, and dead reckoning such as INS using a Kalman filter. However, it may suffer from INS noise, GPS noise and, especially, GPS outage. Map-matching is an additional facility to reduce errors caused by GPS outage. Usually, it has to trade-off between the performance and the complexity. In this paper, we have proposed a new map-matching algorithm called street tracking algorithm (STA) to not only correct the position error, but also estimate the velocity and the heading of the navigation system. When the GPS signal is lost, the Kalman filter is put in prediction mode and the STA is enabled. The raw acceleration of inertial measurement unit measured in body frame is also brought directly to STA as an input. The experimental result has shown that when GPS signal is lost, we can control the position error at around 2.5 m, and the velocity er...
TL;DR: A synthetic shadow detection algorithm using combination of Hessenberg decomposition (HD) and principal component analysis (PCA) is proposed to improve the performance of shadow detection and demonstrates the efficiency and effectiveness of this algorithm in the intelligent transportation systems.
Abstract: Shadow removing is an important issue in performance of intelligent transportation systems. Moving shadows cause confusion and errors in moving object detection, since they cannot be removed from foreground using commercial background subtraction methods. In this paper, a synthetic shadow detection algorithm using combination of Hessenberg decomposition (HD) and principal component analysis (PCA) is proposed. The HD and PCA are applied to improve the performance of shadow detection. At first, the background image is obtained using moving average method and adaptive background estimation. The moving objects in the foreground image can be accurately obtained via the background subtraction method. In this algorithm, the candidate shadow region is estimated by using HD. With regard to ability of HD in the decomposition of foreground image into two parts as shadow and object, we should calculate the HD of foreground image and determine the shadow and object regions. In this procedure, some parts of veh...
TL;DR: In this paper, an ultrawideband (UWB) antenna with switchable band-notch for cognitive radio applications is presented. But the proposed antenna has a simple structure and compact size of 18 × 18 mm2.
Abstract: This paper presents an ultrawideband (UWB) antenna with switchable band-notch for cognitive radio applications. The proposed antenna has a simple structure and compact size of 18 × 18 mm2. The designed antenna consists of a rectangular radiation patch with a rectangular-shaped element (p) etched on it. Also two rectangular-shaped parasitic elements (g1, g2) are embedded on the ground plane that is very critical to achieve the band-notch in wireless local-area network (WLAN) band. One ideal switch (SW) is inserted between the two rectangular parasitic elements on the ground plane. The function of the antenna can be changed by tuning status of the SW that make the notch band in the WLAN band (5.15–5.825 GHz). The UWB antenna is used for spectrum sensing in cognitive radio and the switchable band-notched antenna with filtering characteristic for reconfigurable operation. Also, a good agreement is found between the simulated and the measured reconfigurable antenna properties.
TL;DR: In this paper, a planar integrated ultra-wideband (UWB)/frequency-reconfigurable narrowband monopole antenna is proposed, which can operate from wideband to narrowband by activating PIN diode switches in the structure.
Abstract: A single-port compact planar integrated ultra-wideband (UWB)/frequency-reconfigurable narrowband monopole antenna is proposed. Reconfigurability is achieved by inserting a varactor-diode tuned bandpass filter into the feed line of the UWB antenna. The antenna operation is changed from wideband to narrowband by activating PIN diode switches in the structure. Good tunability obtained within a wide sensing band of 2.2–6 GHz is significant for cognitive radio applications.
TL;DR: In this article, the authors investigated the impact of wind generators on power system stability and showed that flexible alternating current transmission system (FACTS) devices have significant influence on system performance, especially series one to increase the stability of the system.
Abstract: Reduction in fossil fuels and environmental aspect of them has led to the increasing need to the renewable energies such as wind power systems and other distributed generators (DGs) all over the world. With growing usage of wind energy in power systems, impact of wind generators on power system stability becomes more important than before. Since flexible alternating current transmission system (FACTS) devices have significant influence on system performance, especially series one to increase the stability of the system, in this work, thyristor-controlled series capacitor (TCSC) has been used. In this paper, also wind and other DGs as a hybrid energy production system are used and stabilization of power system using TCSC is investigated. Finally, it has been shown that, in addition to TCSC, other DGs are also used in maintaining the quality of supply, power system security and stability.
TL;DR: A dynamic data replication strategy to enhance the performance of software system is shown and to identify the suitable file to replicate and to decide respective number of replicas, popularity degree and replica factor are calculated.
Abstract: Information technology systems deployed by enterprises should not only fulfil their business functionalities but also cater to Quality of Service concerns such as Availability, Scalability, and Performance. To enhance the system performance, the system availability is an important factor and to improve the system availability, one of the strategies is replicating the frequently accessed data to multiple suitable locations which is a practical choice as the users can access the data from a nearby site. This is, however, not the case for replicas which must have a preset number of copies on several locations. How to decide a sensible number and right location for replicas have become an important issue in cloud computing. In this paper, we show a dynamic data replication strategy to enhance the performance of software system. To identify the suitable file to replicate and to decide respective number of replicas, we calculate popularity degree and replica factor. We use the fuzzy logic system to iden...
TL;DR: The proposed single input fuzzy logic controller (SIFLC) offers a significant reduction in rule inferences and simplifies the tuning of control parameters and the execution time of SIFLC is found to be lesser than CFLC.
Abstract: This paper describes the application of single input fuzzy logic controller (SIFLC) for three-phase shunt active power filter. The advantage of the fuzzy logic controller is that it does not require mathematical modelling of the system. The application of two-input fuzzy logic controller to three-phase shunt active power filter is reported in literature. But the two-input fuzzy logic controller needs large set of rules for optimum performance. The SIFLC reduces conventional two-input fuzzy logic controller to single input fuzzy logic controller. The SIFLC offers a significant reduction in rule inferences and simplifies the tuning of control parameters. An SIFLC is designed for three-phase two-level active power filter. A shunt active power filter with SIFLC is simulated for nonlinear load in the MATLAB Simulink environment. The hysteresis controller is used to generate the switching pulses. The simulated response with SIFLC is found to be better than conventional fuzzy logic controller (CFLC). Als...
TL;DR: This paper has designed and implemented a connectivity-based cross-layer opportunistic forwarding protocol for mobile wireless sensor networks and exhibits 22% improvement in energy consumption compared to energy efficient opportunistic routing (EEOR) and also significant improvements for other performance parameters.
Abstract: Mobile wireless sensor networks (MWSNs) consist of many sensor nodes that are randomly distributed in the environment to gather information. In MWSNs, the transmission path is affected due to node mobility and node failures. Routing protocols in MWSNs must adjust to topology changes and should determine the path with minimum overheads. Some of the existing works on the opportunistic routing minimize the energy consumption, but have large overheads and duplicate packet transmissions. In this paper, we have designed and implemented a connectivity-based cross-layer opportunistic forwarding protocol for mobile wireless sensor networks. We estimate the expected energy consumption cost for forwarding the data using prioritized forwarder list and node's connectivity metric. Connectivity metric signifies the ability of node to partition the network on its failure. To reduce retransmissions, we implement forwarding agreement mechanism among the nodes in the forwarder list, if the desired relay node has mov...