International Journal of Scientific Engineering and Technology Research: 2015

Fuzzy Logic Control Based DTC-SVM Adaptive Stator Flux Observer For Induction Motors

Fuzzy Logic Control Based DTC-SVM Adaptive Stator Flux Observer For Induction Motors
Authors:C. ASHOK KUMAR, S. UMA MAHESWARI, C. SUBBA RAMI REDDY

Abstract: A combination of Direct Torque Control (DTC) and Space Vector Modulation (SVM) for an Induction Motor (IM) drive is defined in this paper. A two-level SVPWM inverter is delivered to the induction motor drive. Using IM model in the stator D-Q axes reference frame. The inverter voltage is achieved based on input- output feedback linearization control. This paper signifies a Fuzzy Logic Controller (FLC) for the proposed system. The inputs to the fuzzy logic controller are the variables of speed error and change of speed error whereas the output is change in switching torque. The effectiveness and validity of the proposed control approach, attained from the variable methods those are DTC-SVM and FUZZY LOGIC CONTROL are compared by simulation results.

Keywords: Direct Torque Control (DTC), Adaptive Stator Flux Observer Feedback Linearization, Robust, Space Vector Modulation, And Fuzzy Logic Control.

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Personalized QoS Ranking Prediction Framework for Cloud Services

Personalized QoS Ranking Prediction Framework for Cloud Services
Authors:A. AMARESWARI, S. SIVASKANDHA, CH. RAJAKISHORE

Abstract: Building prime quality cloud applications become associate degree in real time needed analysis downside in cloud computing technology. Non-functional performance of cloud services is often represented by Quality of Service (QoS). To accumulate QoS values, real-world usage of services candidates are typically needed. At this time, there\'s no framework that may permit users to estimate cloud services and rank them supported their QoS values. This paper intends to framework and a mechanism that measures the standard and ranks cloud services for the users. Cloud Rank framework by taking the advantage of past service usage experiences of different users. So it will avoid the time overwhelming and dear world service invocation. This man oeuvre determines the QoS ranking directly mistreatment the two customized QoS ranking prediction approach i.e., CloudRank1 and CloudRank2. These algorithms certify that the active services are accurately satisfied. The inside purpose is ranking prediction of consumer facet QoS properties, that doubtless have completely different values for dissimilar users of the similar cloud service. It estimates every and each one the someone services at the user-side and rank the services supported the discovered QoS values.

Keywords: Quality of Service (QoS).

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Optimal Route Query Processing on Temporal Constraints Using BFS Algorithm

Optimal Route Query Processing on Temporal Constraints Using BFS Algorithm
Authors:E. SREEJA, N. SANDEEP CHAITANYA

Abstract: Given a set of spatial believability DS, commemoration of which is connected with total data, e.g., restaurant, pub, and so forth, the ideal boulevard concern finds the shortcut path that begins from the worry, and spreads a client detailed set of classes. The client should determine fragmentary conformity stipulations in the midst of modified classes, e.g., a restaurant must be gone by before a pub. Past arrangement has concentrated on a fitting case zone the worry contains without a doubt the change of all classifications to be gone to. What's more, we quarrel how the proposed strategies can be acclimatized to affirmation an option of the ideal boulevard inquiries, in which the course just needs to canopy a subset of the acclimated classifications. Broad investigations, application both outright and built modified works sets, avow that the proposed arrangements are capable and reasonable, and beat supreme systems by abundant edges.

Keywords: Computations, Significant, Acknowledgement

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Calculate Future for Mobile Social System using Cloud Computing

Calculate Future for Mobile Social System using Cloud Computing
Authors:JAGADISH SHARMA UPADHYAYULA, D.SRINIVAS

Abstract: The recent cloud computing technology, with its rich resources to compensate for the limitations of mobile devices and connections, can potentially provide an ideal platform to support the desired mobile services. In this paper, we calculate Features for Mobile-Social TV System using Cloud Computing (CloudMoV) is proposed. This system effectively utilizes both PaaS (Platform-as-a-Service) and IaaS (Infrastructure-as-a-Service) cloud services to offer the living-room experience of video watching to a group of disparate mobile users who can interact socially while sharing the video. A surrogate, performs efficient stream transcoding that matches the current connectivity quality of the mobile user is introduced. In this paper, we propose the design of a Cloud-based, novel Mobile Social TV system (CloudMoV). The system effectively utilizes both PaaS (Platform-asa-Service) and IaaS (Infrastructure-as-a-Service) cloud services to offer the living-room experience of video watching to a group of disparate mobile users who can interact socially while sharing the video. To guarantee good streaming quality as experienced by the mobile users with time-varying wireless connectivity, we employ a surrogate for each user in the IaaS cloud for video downloading and social exchanges on behalf of the user. In cloud mobile social TV, mobile users can import a live or on-demand video to watch from any video streaming site and invite their friends to watch the video concurrently, and chat with their friends while enjoying the video. It therefore blends viewing experience and social awareness among friends on the move. Social interactions among the users, in terms of spontaneous textual exchanges, are effectively achieved by efficient designs of data storage with BigTable and dynamic handling of large volumes of concurrent messages in a typical PaaS cloud. These various designs for flexible transcoding capabilities, battery efficiency of mobile devices and spontaneous social interactivity together provide an ideal platform for mobile social TV services.

Keywords: Computers And Information Processing, Mobile Computing, Communications Technology, TV, Mobile TV.

INTRODUCTION

There has been an rapid reinvention in the smartphones [30] by combining the features of a mobile phone with those of another popular consumer device, such as a personal digital assistant (PDA), a media player, a digital camera, and/or a GPS navigation unit. Modern smartphones include all of those features plus the features of a laptop, including web browsing, Wi-Fi, and third party applications and accessories, multiple microprocessor core and gigabyte RAMs. The most popular smartphones today are powered by Google's Android and Apple's iOS and the wide deployment of 3G broadband cellular networks. Many mobile social or media applications have emerged, truly gaining mass acceptance and are still impeded by the limitations of the current mobile and wireless technologies, among which battery lifetime and unstable connection bandwidth are the most difficult ones.

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Improved Power Quality for Renewable Power Generation Systems Presence of Non-Linear Loads

Improved Power Quality for Renewable Power Generation Systems Presence of Non-Linear Loads
Authors:A. NAGENDRA BABU, M. RAMA MOHAN RAO

Abstract: The performance analysis of four-leg voltage-source inverter using a Fuzzy logic control scheme is presented. The use of a four-leg voltage-source inverter allows the reduction of current harmonic components, as well as unbalanced and Negative sequence currents generated by single-phase nonlinear loads. A comparison of the proposed method against the conventional proportional integral is illustrated with inverter topologies through simulation results and a clear advantage of the fuzzy logic control can be observed.

Keywords: Active Power Filter, Current Control, Predictive Control, Four-Leg Converters, Fuzzy Controller.

INTRODUCTION

DG’s affects power quality due to its nonlinearity. The non-uniform nature of power generation directly affects voltage regulation and creates voltage distortion in power systems. This new scenario in power distribution systems will require more sophisticated compensation techniques. Although active power filters implemented with three-phase four-leg voltage-source inverters (4L-VSI) have already been presented in technical literature. The primary contribution of this paper is Fuzzy logic controller designed and implemented specifically for this application. Traditionally, active power filters have been controlled using a predictive control technique, such as fuzzy logic or adaptive, for the current as well as for the dc-voltage loops. Fuzzy controllers use the non-linear model, which is closer to real operating conditions compare to predictive control. An accurate model obtained using fuzzy controller improves the performance of the active power filter, especially during transient operating conditions, because it can quickly follow the current-reference signal while maintaining a constant dcvoltage. The mathematical model of the 4L-VSI and the principles of operation of the proposed predictive control scheme, including the design procedure. The complete description of the selected current reference generator implemented in the active power filter is also presented.

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A New Strategy to Control Reactive Power of a PMS Wind Generator with Matrix Converter

A New Strategy to Control Reactive Power of a PMS Wind Generator with Matrix Converter
Authors:C. JAYA KRISHNA, K. MEENENDRANATH REDDY, G. VENKATA SURESH BABU

Abstract: In this paper, a new strategy is proposed to increase the maximum achievable grid-side reactive power of a matrix converter-fed PMS wind generator. Unlike conventional back-to-back converters in which a huge dc-link capacitor makes the control of the generator and grid-side converters nearly independent, a matrix converter control the generator and grid-side quantities simultaneously. Matrix converter is a direct AC-AC converter topology that is able to directly convert energy from an AC source to an AC load without the need of a bulky and limited lifetime energy storage element. Due to the significant advantages offered by matrix converter, such as adjustable power factor, capability of regeneration and high quality sinusoidal input/output waveforms, matrix converter has been one of the AC–AC topologies that receive extensive research attention for being an alternative to replace traditional AC-DC-AC converters in the variable voltage and variable frequency AC drive applications. Different methods for controlling a matrix converter input reactive power is investigated. It is shown that in some modulation methods, the grid-side reactive current is made from the reactive part of the generator-side current. In other modulation techniques the grid side reactive current is made from the active part of the generator-side current. In the proposed method, which is based on a generalized SVD (singular valued decomposition) modulation method, the grid side reactive current is made from both active and reactive parts of the generator-side current. In existing strategies, a decrease in generator speed and output active and reactive power will decrease the grid-side reactive power capability. A new control structure is proposed which uses the free capacity of the generator reactive power to increase the maximum achievable grid-side reactive power. Simulation results for a case study show an increase in the grid-side reactive power at all wind speeds if the proposed method is employed.

Keywords: Permanent Magnet Synchronous Generator (PMSG), Matrix Converter, Reactive Power Control, Singular Value Decomposition (SVD) Modulation, Space Vector Modulation (SVM).

INTRODUCTION

In an integrated power system, efficient management of active and reactive power flows is very important. Quality of power supply is judged from the frequency and voltage of the power supply made available to the consumers. While frequency is the measure of balance between power generated (power available) and MW demand impinged on the system, the voltage is indicative of reactive power flows. In a power system, the ac generators and EHV and UHV transmission lines generate reactive power. Industrial installations whether small or large as also the irrigation pump motors, water supply systems draw substantial reactive power from the power grid. The generators have limited defined capability to generate reactive power- this is more so in respect of large size generating units of 210 MW/500 MW capacity. Generation of higher reactive power correspondingly reduces availability of useful power from the generators. During light load conditions, there is excess reactive power available in the system since the transmission lines continue to generate the reactive power...

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Novel Carry Select Adder with Low Power Considerations

Novel Carry Select Adder with Low Power Considerations
Authors:AVUTHU VINOD KUMAR REDDY, AVUTHU SRIKANTH REDDY, AYYAGARI RAMYA

Abstract: The CSLA is used in many computational systems to alleviate the problem of carry propagation delay by independently generating multiple carries and then select a carry to generate the sum. However, the CSLA is not area efficient because it uses multiple pairs of Ripple Carry Adders (RCA) to generate partial sum and carry by considering carry input, then the final sum and carry are selected by the multiplexers (mux). The basic idea of this work is to use Binary to Excess-1 Converter (BEC) instead of RCA in the regular CSLA to achieve high speed and low power consumption.

Keywords: Low Power VLSI; Carry Select; RCA; BEC; VLSI.

INTRODUCTION

The major speed limitation in any adder is in the production of carries and many authors have considered the addition problem. The basic idea of the proposed work is using n-bit Binary to Excess-1 Converters (BEC) to improve the speed of addition. This logic can be implemented with Carry Select Adder to Achieve Low Power and Area Efficiency. The proposed 32-bit Carry Select Adder compared with the Carry Skip Adder (CSKA) and Regular 32-bit Carry Select Adder. The CSLA is used in many computational systems to alleviate the problem of carry propagation delay by independently generating multiple carries and then select a carry to generate the sum.

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Mitigation of Harmonics in Seven Level Inverter by using PSO Algorithm

Mitigation of Harmonics in Seven Level Inverter by using PSO Algorithm
Authors:B.RAJITHA

Abstract: In nowadays the multilevel inverters are increased due to their ability to generate high quality output wave forms with low switching frequency. The different multilevel inverter structures are Cascaded H-Bridge, diode clamped and flying capacitor multilevel inverter. A Cascaded H-bridge Inverter (CHB) is a multilevel topology which is formed from the series connection of H-bridge cells. In this paper the Selective harmonic elimination pulse width modulation strategy is eliminating low-order harmonics by solving nonlinear equations. The selective harmonic elimination method (SHE-PWM) at fundamental frequency switching scheme has been implemented using the Particle Swarm Optimization (PSO) Algorithm that produces all possible solution sets when they exist. In comparison with other suggested methods, the proposed technique has many advantages such as: it can produce all possible solution sets for any numbers of multilevel inverter without much computational burden; speed of convergence is fast etc. This paper is to reduce the total harmonic distortion (THD) and elimination of selective lower order harmonics such as 5thand 7th order with minimum harmonic distortion and obtain desired fundamental voltage. The results prove that the PSO algorithm converges successfully to the global solution faster than other algorithms. The simulation will be obtained by using MATLAB/SIMULINK.

Keywords: Multilevel Inverters, Selective Harmonic Elimination (SHEPWM), Cascaded H-Bridge, Particle Swarm Optimization.

INTRODUCTION

In recent years, Multilevel Inverters have received more attention because of their ability to generate high quality output waveforms with low switching frequency. Multilevel Inverters have been considered as an optimum choice to provide better quality power to the load. In Multilevel Inverters the desired output voltage is achieved by Suitable low combination of multiple low dc voltage sources used at the input side. As the number of dc sources increases the output voltage will be pure closer to sinusoidal waveform. In this paper, an attempt has been made to improve the quality of power. There are three types of conventional structures for multilevel inverters such as diode clamped multilevel inverter, flying capacitor multilevel inverter and cascaded multilevel inverter. There are many popular methods are used to reduce the harmonics in order to get an effective results. The methods for high switching frequency are Sinusoidal PWM and Space Vector PWM. For low switching frequency methods are space vector modulation and selective harmonic elimination. The spwm, svpwm techniques are don’t eliminate low order harmonics. So the selective harmonic mitigation (SHM-PWM) technique for generating pwm signals that can be eliminate selected lower order harmonics from voltage sources inverter.

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RDH (Reversible Data Hiding) in Encrypted Images by Reserving Room Before Encryption

RDH (Reversible Data Hiding) in Encrypted Images by Reserving Room Before Encryption
Authors:DURGA S PATIL, DR.SUDHIR S KANADE

Abstract: Now a day, more attention is to reversible data hiding (RDH) in encrypted images as well as in audio and video, by using RDH method excellent property that the original image (cover) can be receives as it is recovered after embedded data is extracted also protecting the image content’s confidentiality. All previous methods embedding data into image by reversibly vacating room in the encrypted images, which may be result as some errors on data extraction and/or image restoration. That mean some secrete information is loss in data extraction also degraded quality of image. In this paper, we propose a new method by reserving room before encryption .By using the new RHD method improver’s efficiency of image. The proposed method improves efficiency & quality encrypted image usually used in medical area, aromatic etc. The new Algorithm Used in novel RDH is reducing noise Effect.

Keywords: Reversible Data Hiding, Image Encryption, Novel Method Of RDH, Encryption Techniques, Difference Expansion, Histogram Shift.

INTRODUCTION

Reversible data hiding (RDH) is a technique in image processing area for encryption, by which the original cover can be losslessly recovered after the embedded message, is extracted. The RDH approach is widely used in medical science, defense field and forensic lab, where there is no degradation of the original content is allowed. Since more research RDH method in recently. In theoretical aspect ratedistortion model for RDH Kalker and Willems [2], through which they proved the rate-distortion bounds of RDH for memory less covers and proposed a recursive code construction which, however, does not approach the bound. The recursive code construction for binary covers and proved that this construction can achieve the rate-distortion bound as long as the compression algorithm reaches entropy, which establishes the equivalence between data compression and RDH for binary covers. Many RDH techniques have emerged in recent years. Fridrich et al [3] constructed a general framework for RDH for method. By first extracting compressible features of original cover and then compressing them lossless, spare space can be saved for embedding auxiliary data.

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A New Approach of Data Security using Steganography Technique

A New Approach of Data Security using Steganography Technique
Authors:MANOHAR N SAYYADPURKAR, C.G.PATIL

Abstract: Steganography is the art of hiding the existence of data in another transmission medium to achieve secret communication. It does not replace cryptography but rather boosts the security using its obscurity features. Steganography method used in this paper is based on biometrics. And the biometric feature used to implement steganography is skin tone region of images [1]. Here secret data is embedded within skin region of image that will provide an excellent secure location for data hiding. For this skin tone detection is performed using HSV (Hue, Saturation and Value) color space. Additionally secret data embedding is performed using frequency domain approach - DWT (Discrete Wavelet Transform), DWT outperforms than DCT (Discrete Cosine Transform). Secret data is hidden in one of the high frequency sub-band of DWT by tracing skin pixels in that sub-band. Different steps of data hiding are applied by cropping an image interactively cropping results into an enhanced security than hiding data without cropping i.e. in whole image, so cropped region works as a key at decoding side. This study shows that by adopting an object oriented steganography mechanism, in the sense that, we track skin tone objects in image, we get a higher security. And also satisfactory PSNR (Peak- Signal-to-Noise Ratio) is obtained.

Keywords: Biometrics; Skin Tone Detection; DWT; DCT; Cropping; Security; PSNR.

INTRODUCTION

In this highly digitalized world, the Internet serves as an important role for data transmission and sharing. However, since it is a worldwide and publicized medium, some confidential data might be stolen, copied, modified, or destroyed by an unintended observer. Therefore, security problems become an essential issue. Encryption is a well know procedure for secured data transmission [2]. Frequently used encryption methods include RSA, DES (Data encryption standard).Although encryption achieves certain security effects, they make the secret messages unreadable and unnatural or meaningless. These unnatural messages usually attract some unintended observers‟ attention. This is the reason a new security approach called “steganography” arises. As an example, the cover text [3]: “I‟m feeling really stuffy. Emily‟s medicine wasn‟t strong enough without another febrifuge.” Hides the sentence “Meet me at nine” If the reader retains the second letter of each word in sequence. In steganography secret message is the data that the sender wishes to remain confidential and can be text, images, audio, video, or any other data that can be represented by a stream of bits. The cover or host is the medium in which the message is embedded and serves to hide the presence of the message.

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A Novel Framework to Detect and Migrate Collaborative Attacks in the Cloud Network

A Novel Framework to Detect and Migrate Collaborative Attacks in the Cloud Network
Authors:N.BALARAJ, SAKSHI SIVA RAMAKRISHNA

Abstract: Security is an important issue in cloud environment. Attackers can explore vulnerabilities of a cloud system and compromise virtual machines to deploy further large scale Distributed Denial Of Service.(DDoS). To prevent vulnerable virtual machine from being compromised in cloud a multiphase distributed vulnerability detection, measurement and countermeasure selection mechanism called NICE have been proposed. These systems are used by number of organizations to detect the weaknesses threats and preventing them. For this purpose, these systems became an important part of the security in nearly every organization. The system and security evaluations demonstrate the efficiency and effectiveness of the proposed solution.

Keywords: Cloud Computing, Network Security, Intrusion Detection, Zombie Detection, Attack Graph.

INTRODUCTION

Users migrating to the cloud consider security as the most important factor. A recent Cloud Security Alliance (CSA) survey shows that among all security issues, abuse and nefarious use of cloud computing is considered as the top security threat, in which attackers can exploit vulnerabilities in clouds and utilize cloud system resources to deploy attacks. In traditional data centers, where system administrators have full control over the host machines, vulnerabilities can be detected and patched by the system administrator in a centralized manner. However, patching known security holes in cloud data centers, where cloud users usually have the privilege to control software installed on their managed VMs, may not work effectively and can violate the Service Level Agreement (SLA). Furthermore, cloud users can install vulnerable software on their VMs, which essentially contributes to loopholes in cloud security. The challenge is to establish an effective vulnerability/attack detection and response system for accurately identifying attacks and minimizing the impact of security breach to cloud users addressed that protecting ”Business continuity and services availability” from service outages is one of the top concerns in cloud computing systems.

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Enhanced Image Hiding in Audio Stegnography using Discrete Cosine Transform and Skin Detection

Enhanced Image Hiding in Audio Stegnography using Discrete Cosine Transform and Skin Detection
Authors:B.SREEDHAR, D.VIJENDRA KUMAR

Abstract: Now days, security is an important problem in hacking technologies such as internet, digital devices and so on. To solve the security problem, we can use one of the method called steganography. The paper presents the hiding security image into audio signal. For hiding image in audio, skin detection and discrete cosine transform are used. In audio steganography, hiding image is also called cover or host image. The process of hiding cover image into audio signal is called stego signal. The proposed method is effective and less time efficient. The experimental results shows the invisible image in audio signal after embedded step and recover the security image accurately without distortion at decoding stage.

Keywords: Skin Detection, DCT, Audio Data Hiding and Steganography.

INTRODUCTION

The Steganography word is come from the Greek words “stegos” meaning “cover” and the name “grafia” as “writing” defining it as “covered writing” [1]. Steganography definition of hiding information “in plain sight”. This technique relies on a message being encoded and hidden in a transport layer in such a way as to make the existence of the message unknown to an observer [2]. The notion of data hiding or steganography was first introduced with the example of prisoners' secret message by Simmons in 1983 [3]. Watermarking is similar to steganography. It is “the practice of imperceptibly altering a Work to embed a message about that Work” [4]. Steganography satisfy two requirements. The first requirement is transparency that is hostimage (image containing any some data) and stego image (image containing secret information) must be perceptually indiscernible. The second requirement is the high data rate of the encodedata [5]. In a computer based secret messages, audio Stenography system are embedded in digital audio. Used audio signal as a hostimage to audio Stenography .

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THD Reduction using 12-Pulse Converter for Vector Controlled Induction Motor Drive

THD Reduction using 12-Pulse Converter for Vector Controlled Induction Motor Drive
Authors:C. SUBBA RAMI REDDY, G.VENKATA LAKSHMI, P.RRAJESWARI

Abstract: In this paper, a novel autotransformer with a reduced kilovolt-ampere rating is presented for harmonic current reduction in twelve-pulse ac-dc converter-fed vector-controlled induction motor drives (VCIMDs). Different transformer arrangements for 12-pulse-based rectification are also studied and a novel harmonic mitigator capable of suppressing fifth, seventh, and 11th (most dominant harmonics) in the supply current is presented. The design procedure for the proposed autotransformer is presented to show the flexibility in the design for making it a cost-effective replacement suitable for retrofit applications, where presently a six-pulse diode bridge rectifier is being used. The effect of load variation on VCIMD is also studied to demonstrate the effectiveness of the proposed harmonic mitigator. A set of power-quality indices on input ac mains and on a dc bus for a VCIMD fed from different 12-pulse ac-dc converters is given to compare their performance.

Keywords: Autotransformer, Multipulse AC–DC Converter, Power-Quality Improvement, Vector-Controlled Induction Motor Drive (VCIMD).

INTRODUCTION

With the proliferation of power-electronic converters, the majority of dc drives are being replaced by variable frequency induction motor drives. These variable frequency induction motor drives are generally operated in vector control [1], as it is an elegant way of achieving highperformance control of induction motors in a way similar to the dc motor. These vector-controlled induction motor drives (VCIMDs) are fed by an uncontrolled ac–dc converter which results in injection of current harmonics into the supply system. These current harmonics, while propogating through the finite source impedance, result in voltage distortion at the point of common coupling, thereby affecting the nearby consumers. Various methods based on the principle of increasing the number of pulses in ac–dc converters have been reported in the literature to mitigate current harmonics [2]–[4]. These methods use two or more converters, where the harmonics generated by one converter are cancelled by another converter, by proper phase shift. The autotransformer-based configurations [2] provide the reduction in magnetics rating, as the transformer magnetic coupling transfers only a small portion of the total kilovoltampere of the induction motor drive. These autotransformerbased schemes considerably reduce the size and weight of the transformer. Autotransformer-based 12-pulse ac–dc converters have been reported [4] for reducing the total harmonic distortion (THD) of the ac mains current. To ensure equal power sharing between the diode bridges and to achieve good harmonic cancellation, this topology needs interphase transformers and impedance-matching inductors, resulting in increased complexity and cost. Moreover, the dc-link voltage is higher, making the scheme nonapplicable for retrofit applications.

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A Novel Cascaded H-Bridge Multilevel Converter with Reduced Number of Switches

A Novel Cascaded H-Bridge Multilevel Converter with Reduced Number of Switches
Authors:M.VIJAYA, M.REDDY PRASANNA, C.SUBBA RAMI REDDY

Abstract: In this paper mainly focused on the design and implementation of new topology in a single phase five level cascaded H-bridge multilevel inverter by using only a five switches and two DC power source. The main objective of this paper is to increase number of levels with a low number of switches and sources at the output without adding any complexity to the power circuit.. The optimal structures of this topology are investigated for various objectives, such as minimum number of switches and capacitors, and minimum standing voltage on switches for producing maximum output voltage steps. A new algorithm for determination of dc voltage sources’ magnitudes has also been presented. The proposed topology results in reduction of the number of switches, losses, installation area, and converter cost. The operation and performance of the proposed multilevel converter has been verified by the simulation and experimental results of a single-phase 53-level multilevel converter.

Keywords: Bidirectional Switch, Full-Bridge Topology, Multilevel Converter, Sub Multilevel Converter.

INTRODUCTION

The Concept of multilevel converters was introduced in 1975 [2]. The term multilevel began with the three level converters [3]. A multilevel converter is a power electronic system that synthesizes a desired output voltage from several levels of dc voltages as inputs. With an increasing number of dc voltage sources, the converter output voltage waveform approaches a nearly sinusoidal waveform while using a fundamental frequency-switching scheme. Compared with the traditional two-level voltage converter, the primary advantage of multilevel converters is their smaller output voltage step, which results in high power quality, lower harmonic components, better electromagnetic compatibility, and lower switching losses. Numerous industrial applications have begun to require high power apparatus in recent years. Power electronic inverter become popular for various industrial drives applications. Recently, multilevel power conversion technology has been developing the area of power electronics very rapidly with good potential for further developments. As a result the most attractive applications of this technology are in the medium to high voltage ranges. A multilevel converter not only achieves high power rating, but also enables the use of renewable energy sources. Renewable energy sources such as photovoltaic, wind, and fuel cells can be easily interfaced to a multilevel converter system for a high power application proposed topology has less switches than that of [2] in symmetric topology. The H-bridge topology was followed by the diode-clamped converter that utilized a bank of series capacitors.

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Designing and Fabrication of Gearless Electric Car for Handicaps

Designing and Fabrication of Gearless Electric Car for Handicaps
Authors:ER.KANWAR J S GILL, VISHU GARG, JASPREET SINGH, JASPREET SINGH, DARSHPREET SINGH, SEHAJPREET SINGH, MANISH KUMAR, PRINCE BIDALIYA, UPENDERA KUMAR, DEEPAK MOUDGILL

Abstract: The development of internal combustion engine vehicles, especially automobiles, is one of the greatest achievements of modern technology. Automobiles have made great contributions to the growth of modern society by satisfying many of its needs for mobility in everyday life. The rapid development of the automotive industry, unlike that of any other industry, has prompted the progress of human society from a primitive one to a highly developed industrial society.[1] The automotive industry and the other industries that serve it constitute the backbone of the word’s economy and employ the greatest share of the working population. However, the large number of automobiles in use around the world has caused and continues to cause serious problems for the environment and human life. Air pollution, global warming, and the rapid depletion of the Earth’s petroleum resources are now problems of paramount concern. In recent decades, the research and development activities related to transportation have emphasized the development of high efficiency, clean, and safe transportation. Electric vehicles, hybrid electric vehicles, and fuel cell vehicles have been typically proposed to replace conventional vehicles in the near future. This paper describes the work done in designing and fabrication of gearless drive electric car which is meant specially for handicaps, not only limited to this feature this vehicle can be used as multiutility vehicle.

Keywords: Gearless, Electric Car, Handicaps, Multiutility, Designed, Fabricated.

INTRODUCTION

At present, all vehicles rely on the combustion of hydrocarbon fuels to derive the energy necessary for their propulsion. Combustion is a reaction between the fuel and the air that releases heat and combustion products. The heat is converted to mechanical power by an engine and the combustion products are released into the atmosphere. A hydrocarbon is a chemical compound with molecules made up of carbon and hydrogen atoms. Ideally, the combustion of a hydrocarbon yields only carbon dioxide and water, which do not harm the environment. Indeed, green plants “digest” carbon dioxide by photosynthesis. [2]Carbon dioxide is a necessary ingredient in vegetal life. Animals do not suffer from breathing carbon dioxide unless its concentration in air is such that oxygen is almost absent. Actually, the combustion of hydrocarbon fuel in combustion engines is never ideal. Besides carbon dioxide and water, the combustion products contain a certain amount of nitrogen oxides (NO2), carbon monoxides (CO), and unburned hydrocarbons (HC), all of which are toxic to human health. Highlight a section that you want to designate with a certain style, and then select the appropriate name on the style menu. The style will adjust your fonts and line spacing.

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Access Control in Cloud Computing Based on Broadcast Group Key Management

Access Control in Cloud Computing Based on Broadcast Group Key Management
Authors:UDDAGIRI SIRISHA, DR.S.MADHAVI

Abstract: In the most recent a few years, cloud computing has developed as a standout amongst the most powerful standards in the IT business, and has became a broad consideration from both the scholarly world and business. In cloud computing, Cloud File storage needs users to handover their valuable data to Cloud Providers (CP). Due to this situation, the security and privacy of the outsourced data by the users became an issue. Several plans for access control of outsourced data were proposed earlier, in that Attribute-Based encryption (ABE) is one. Later on, because of its difficult implementation over complex access control policies, we proposed an adaptable and fine-grained access control plan called hierarchical attribute-set-based encryption (HASBE) with a hierarchical structure of users. After that we joined the advantages of HASBE plan with a new plan called broadcast group key management (BGKM) that uses dynamic key generation based on identity attributes and public information. To deal with the access control of outsourced data in distributed or cloud computing, the implementation of this proposed plan i.e. HASBE with BGKM is proficient and easy.

Keywords: Cloud Computing, Access Control, Data Security, ABE, HASBE, BGKM.

INTRODUCTION

Cloud computing is novel model that is based on virtualization, parallel and distributed, utility processing, and administration arranged building design. In the most recent a few years, distributed or cloud computing has developed as a standout amongst the most powerful standards in the IT business, and has pulled in broad consideration from both the scholarly world and business. The profits of distributed or cloud computing incorporate lessened expenses and capital consumptions, expanded operational efficiencies, adaptability, quick time to market, et cetera. Various business distributed computing frameworks have been manufactured at distinctive levels. With these cloud computing frameworks, on one hand, undertaking clients no more need to put resources into fittings/programming frameworks or contract IT experts to keep up these IT frameworks, accordingly they spare cost on IT framework and human assets; processing utilities provided by cloud computing are consistently offered at a moderately low cost in a pay-as-you-utilize style. In spite of the fact that the extraordinary profits conveyed by cloud computing standards are energizing for IT organizations, scholarly scientists, and potential cloud clients, security issues in distributed computing get to be not kidding snags which, without being fittingly tended to, will anticipate cloud computing far reaching applications and use later on.

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Non-Frontal Low Resolution Face Image Recognition Based on Canonical Correlated Principal Component Analysis

Non-Frontal Low Resolution Face Image Recognition Based on Canonical Correlated Principal Component Analysis
Authors:KARTHIK.T, RAJENDRAPRASAD.D

Abstract: In video surveillance, the face recognition usually aims at recognizing a non-frontal low resolution face image from the gallery in which each person has only one high resolution frontal face image. Traditional face recognition approaches have several challenges, such as the difference of image resolution, pose variation and only one gallery image per person. This paper proposes a new method for face recognition in the case of “one sample per class” using one non-frontal LR input. FH features are super resolved from NFL input by the learnt nonlinear mappings in the coherent space. The nonlinear regression models from the specific non-frontal low resolution image to frontal high resolution features are learnt by radial basis function in subspace built by canonical correlation analysis. Extensive experiments on benchmark database show the superiority of our method.

Keywords: Canonical Correlation Analysis, Non-Frontal Face Recognition, Radial Basis Function, Super Resolution.

INTRODUCTION

Although human beings can easily detect and identify faces in a scene, it is very challenging for an automated system to achieve such objectives. Face recognition has drawn great attention in recent decades, due to its wide range commercial and law-enforcement applications [1]. The challenges become more profound when large variations exist in the face images at hand, e.g., variations in illumination conditions, viewing directions or poses, facial expression, aging, and disguises such as facial hair, glasses, cosmetics and scarves. Despite of these challenges, face recognition has drawn wide attention from researchers in areas of machine learning, computer vision, pattern recognition, neural networks, and so on. Super resolution methods are used for LR Face recognition [2], [3], [4], [5], [6]. In this paper, this work mainly focus on improving the recognition performance in the case where only a single face “snapshot” of LR is available.

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A Novel Approach for Fault Observability and Isolation in Distributed Power System using PMUs

A Novel Approach for Fault Observability and Isolation in Distributed Power System using PMUs
Authors:M.DINESH REDDY, SHAIK HAMEED

Abstract: In a Distributed Power System (DPS), the occurrence of line faults is very frequent due to natural threats to the lines and their ageing. In a big distributed network a fault is occurred at one corner part of the network shows a serious impact on the entire network by causing a severe deviation in its operation there by leading to shut-down of the entire network until or unless the fault was detected and isolated. In this project in order to resolve the above issues we proposed a novel algorithm for DPS security by replacing IEDs in former algorithm with Pharos Measurement Units(PMUs)which determines the occurrence of the faults based on the analysis of voltage and current phasors of Power Distribution Bus (PDB) lines. The method exploits the nodal voltage and mesh current analysis where the phase voltage, impedance and admittance matrices of the network and its dual circuit are developed and utilized for smooth detection and isolation of faults without network malfunction. In addition, this method not only detects and isolates the faults but also informs the same to the technical department for immediate correction. The PMUs are organized as independent region monitoring devices controlled by the control unit of Distributed Power System. The proposed algorithm is implemented and verified in MATLAB.

Keywords: Distributed Power System (DPS), IEDs, Pharos Measurement Units(PMUs).

INTRODUCTION

Faults and device failures affect the power quality in power systems and cause losses for both electric utilities and customers [1]. In distributed generation [4], safety and secure operation of the system highly rely on the level of power system operating condition monitoring. In traditional approaches the measurements provided by the remote terminal units (RTU) at the substations are sent to the control center. This data include real/reactive power in different lines as well as bus voltages and branch currents. The unmeasured states of the system are then estimated by state estimators that reside in the control center. Normal observability in power system is defined as knowing the voltage phasors of all the buses. Fault observability [18], on the other hand, is defined such that a system becomes fault observable when the voltage at two ends of each line and the current at any end of the line are determinable. In general, a system, which is observable in the normal condition, may not be observable for the fault condition. In this project the application of PMUs in fault location [15] is investigated and a method is proposed to effectively reduce the number of required PMUs [16] while retaining the accuracy of fault location [15]. Thus, fault observability [18] is the main focus in this work. In a big distributed network a fault is occurred at one corner part of the network shows a serious impact on the entire network by causing a severe deviation in its operation there by leading to shut-down of the entire network until or unless the fault was detected and isolated. This will lead to a heavy loss to the consumers and industries as it disturbs the production process. Unlike traditional AC distribution systems, protection has been challenging for DC systems.

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Spectrum Sensing Based on Enhanced Energy Detector in Cognitive Radio Communications

Spectrum Sensing Based on Enhanced Energy Detector in Cognitive Radio Communications
Authors:DEEPIKA.B, CH.USHA KUMAR

Abstract: Cognitive radio communication has emerged as an efficient mean of utilization of spectrum for wireless communication. In cognitive radio communication the energy detector logic for spectrum estimation is the most eminent part for estimation of used spectrum over unused spectrum. The estimation error rate for such a system is dependent on the probability based hypothetical estimation approach. Wherein conventional energy detectors make the probability estimation based on derived threshold, the error rate is purely dependent on the accuracy of the threshold limits. In this paper a bi-level threshold modeling is proposed. The bi-level estimation approach presents an approach for non-linearity factor consideration for secondary users in Cognitive Radio communication. The obtained simulative observation illustrates the significance of bilevel estimator logic over conventional estimator logic.

Keywords: Cognitive Radio, Spectrum Estimation, Energy Detector, Bi-Level Limits.

INTRODUCTION

Cognitive radio is an exciting emerging communication model which may be considered as a solution to inefficient usage of fixed allocated licensed frequency spectrum. Significant improvement in spectrum utilization can be achieved by allowing an unlicensed or secondary user (SU) to access a licensed frequency band when the licensed or primary user (PU) is absent. In cognitive radio, SU senses an idle frequency band of a PU, and if a band is found to be idle, SU may transmit over that band. But as soon as PU returns, SU must vacate the band immediately. This complete process requires accurate spectrum sensing to avoid harmful interference to PU. There have been a lot of spectrum sensing techniques. Among those energy detector gives an effective spectrum sensing performance. The energy detector is a very useful non-coherent detector used to detect the presence of PU. It detects the presence of a PU‟s signal by measuring its energy and comparing the measured energy with a predetermined threshold.

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Voltage Stability of Transmission System using Series Capacitor and Static VAR Compensator

Voltage Stability of Transmission System using Series Capacitor and Static VAR Compensator
Authors:CHANDRAMOULI.B, RATANSINGH ATKAR

Abstract: Today, The power system becomes more complicated and large, just to ensure enough energy for all activities. Due to this complexity, the power engineers would face problems like power system stability and power quality, among others. The Reactive power compensation plays an important role in the planning of a power system. This ensures a satisfactory voltage profile and a reduction in power and energy losses within the system. Reactive power also maximizes the real power transmission capability of transmission lines, while minimizing the cost of compensation. The transmission capacity can be increased by using certain compensation devices. Series capacitor and static VAR compensators can contribute to power systems voltage stabilities. Combining these two methods is the subject of this paper. Effect of the presence of series capacitor on static VAR compensator controller parameters and ratings required to stabilize load voltages at certain values are highlighted. Static VAR compensator rating and controller references and gains are found in order to stabilize load voltage at certain specified values. Interrelation between these two means parameters are highlighted. The focus of this paper is on the application of Static VAR Compensator with series capacitor to solve voltage regulation and power transfer capabilities.

Keywords: Static VAR Compensator (SVC), Thyristor Controlled Reactor (TCR), Automatic Voltage Regulator (AVR), Voltage Regulation, MATLAB.

INTRODUCTION

SVC is a mature thyristor based controller that provides rapid voltage control to support electric power transmission voltages during and immediately after major system disturbances. Since the advent of deregulation and the separation of generation and transmission systems in the electric power industry, voltage stability and reactive power-related system restrictions have become an increasingly growing concern for electric utilities. With deregulation came an “open access” rule to accommodate competition that requires utilities to accept generation and load sources at any location in the existing transmission system. This “open access” structure has challenged transmission owners to continually maintain system security, while at the same time trying to minimize costly power flow congestion in transmission corridors. When voltage security or congestion problems are observed during the planning study process, cost effective solutions must be considered for such problems [5]. Traditional solutions to congestion and voltage security problems were to install new costly transmission lines that are often faced with public resistance, or mechanically-switched capacitor banks that have limited benefits for dynamic performance due to switching time and frequency.

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Adaptive Slip Power Recovery System in Three Phase Slip Ring Induction Motor with Synchronous Speed

Adaptive Slip Power Recovery System in Three Phase Slip Ring Induction Motor with Synchronous Speed
Authors:RATANSINGH ATKAR, CHANDRAMOULI.B

Abstract: The research study takes a look at the impact slip rings power losses of three phase slip ring induction motor. The output slip power losses are more during speed control in two methods which we prefer in present days at Electrical industries and in Electrical Laboratory for speed control purpose. One is Doubly-fed method-The speed of the motor is controlled by three variable rheostat of same rating used at the end of output slip terminals of different phases. Second is converting AC slip power into DC-instead of mechanically varying the resistance, the equivalent resistance in the rotor resistance is definitely advantageous compared to Rheostatic controlled, but the problem of poor drive efficiency remains the same. To overcome these losses the 3rd method is designed named modified static Kramer drive system a bridge diode rectifier, a cyclo inverter and a step up transformer. The three phase out put frequency and voltage of synchronous power at slip could be stepped up and converted as same input voltage and frequency. This synchronous power is now fed into main supply to the motor. And motor speed could be controlled by using inverter and the problem of poor drive efficiency is increased.

Keywords: Power Loss Due To Heat, Synchronous Power, Poor Drive Efficiency, Insulation, Cyclo Inverter Synchronous Frequency.

INTRODUCTION

This research study has the impact of the principle of slip power recovery drive particularly to reduce the power losses at output terminals of slip ring induction motor due to the output. Slip power losses are more during speed control due to use of variable resistance (Rheostat) in previous methods. Previous works include the two methods named as Doublyfed: Machine speed control by rotor rheostat in which when output slip terminals were connected to each other with any coil when the motor was at full load. The speed of the rotors was controlled by these variable rheostat of same ratting used at the end of output slip terminals of different phases And the second method is Speed control by converting ac into dc and varying a rheostat: instead of mechanically varying the resistance the equivalent resistance in the rotor circuit can be varied statically by using a diode bridge rectifier and chopper. This electronic control of rotor resistance is definitely advantageous compared to rheostatic control method, but the problem of poor drive efficiency remains the same. The contribution of this paper is to overcome the losses which occur in previous methods. The slip power or synchronous power is converted into dc by diode bridge rectifier and the DC voltage is converted into AC by line commutated inverter and fed back to supply. As the slip power can flow only in one direction, modified static Kramer drive offers speed control below synchronous speed only and improves overall poor drive efficiency of the system.

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FIR High Speed VLSI Design for Area Efficient Parallel Digital Filter Structure for Low Power CMOS Voltage Mode SRAM Cell

FIR High Speed VLSI Design for Area Efficient Parallel Digital Filter Structure for Low Power CMOS Voltage Mode SRAM Cell
Authors:PADMA SILIVERI

Abstract: In this paper we propose a novel design of a low power static random access memory (SRAM) cell for high speed operations. The model adopts the voltage mode method for reducing the voltage swing during the write operation switching activity. Dynamic power dissipation increases when the operating frequency of the SRAM cell increases. In the proposed design we use two voltage sources connected with the Bit line and Bit bar line for reducing the voltage swing during the write “0” or write “1” operation. We use 90 nm CMOS technology with 1 volt of power supply. Simulation is done in Micro wind 3.1 by using BSim4 model. Dynamic power for different frequencies is calculated. We compare it with conventional 6-T SRAM cell. The simulation results show that the power dissipation is almost constant even the frequency of the proposed SRAM model increases. This justifies the reduction of the dynamic power dissipation for high frequency CMOS VLSI design.

Keywords: CMOS; Dynamic Power; SRAM; Voltage Mode; Voltage Swing.

INTRODUCTION

In today’s technology advancement world, Reduction of power consumption makes a device more reliable. The need for devices which dissipate minimum amount of power was a major driving force behind the development of CMOS technologies. Consequently, CMOS devices are best known for low power consumption. However, for minimizing the power requirements for a system, by knowing that CMOS devices may use less power than equivalent devices from other technologies does not do enough [1]. For high speed systems, Low power design has become an essential issue in VLSI design [2]. Normally, dynamic power dissipation dominates in most digital systems. Dynamic power dissipation depends on the switching frequency, supply voltage, and the output voltage swing. Reduction in the supply voltage is the most efficient approach to minimize the dynamic power dissipation. Unfortunately, lower supply voltage leads to degradation in performance dramatically [3]. Lower supply voltage decreases the threshold voltage which will increase the sub-threshold current or leakage current hence the static power dissipation increases. Also by Limiting the output voltage swing, dynamic power and delay can be reduced.

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MDC Based FFT-IFFT Processor for WiMax and 3GPP LTE Systems

MDC Based FFT-IFFT Processor for WiMax and 3GPP LTE Systems
Authors:R.BHANU PRAKASH, G.SRINIVASULU

Abstract: The IFFT/FFT algorithms are the prior choice for many real time processing systems due to their execution speed, flexibility and precision. The FFT/IFFT processor is widely used in various areas such as 3GPP LTE communications, speech and image processing, medical electronics and seismic processing, etc Specifically, in the modern technologies like WiMax and 4G communication systems (OFDM), FFT and inverse FFT play a very important role. Applications based on FFT such as signal and image processing require high computational power, plus the ability to choose the algorithm and architecture to implement it. Proposed method considerably decreases the chip area because the memory requirement usually dominates the chip area in an FFT/IFFT processor, by using the proposed memory scheduling, MDC architecture is proved suitable for FFT/IFFT processors in WiMax and LTE systems, because the butterflies and multipliers are capable of achieving a 100% utilization rate, meanwhile, the characteristics of simple control provided by MDC is maintained in the proposed design using Verilog language in Xilinx software.. This processor can be used in IEEE 802.16 WiMAX and 3GPP LTE applications. The processor was implemented with an UMC 90-nm CMOS technology.

Keywords: Fast Fourier Transform (FFT), Memory Scheduling, WiMAX, 3GPP LTE.

INTRODUCTION

Modern communication technologies IEEE 802.16 WiMax and LTE systems(4G) are capable of very high range of data transmission and reception. ie in terms of MBps and GBps. To process these range of data the demand for long length, high-speed and low-power FFT has increased. OFDM systems are used in these systems to transmit data with higher data rate and avoid Inter Symbol Interference (ISI). In an OFDM communication system, the broadband is partitioned into many orthogonal sub-carriers, in which data is transmitted in a parallel fashion, thus the data rate for each sub-carrier is lowered by a factor of N in a system with N sub-carriers. By this method, the channel is divided into many narrowband flat fading sub-channels. This makes the OFDM system more resistant to the multipath frequency selective fading than the single carrier communication system. The sub-carriers are totally independent and orthogonal to each other. The sub-carriers are placed exactly at the nulls in the modulation spectral of one another. The OFDM transmitter and receiver contain Inverse Fast Fourier Transform (IFFT) and Fast Fourier Transform (FFT), respectively.

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Enhanced Image Hiding in Audio Stegnography using Discrete Cosine Transform and Skin Detection

Enhanced Image Hiding in Audio Stegnography using Discrete Cosine Transform and Skin Detection
Authors:B.SREEDHAR, D.VIJENDRA KUMAR

Abstract: Now days, security is an important problem in hacking technologies such as internet, digital devices and so on. To solve the security problem, we can use one of the method called steganography. The paper presents the hiding security image into audio signal. For hiding image in audio, skin detection and discrete cosine transform are used. In audio steganography, hiding image is also called cover or host image. The process of hiding cover image into audio signal is called stego signal. The proposed method is effective and less time efficient. The experimental results shows the invisible image in audio signal after embedded step and recover the security image accurately without distortion at decoding stage.

Keywords: Skin Detection, DCT, Audio Data Hiding and Steganography.

INTRODUCTION

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