Comparative analysis of QCA adders

Authors: K Roopa, M Surya prakash

Abstract: Quantum-dot cellular automata (QCA) is a novel nanotechnology that gives an altogether higher computational speeds than conventional CMOS, in which polarization of electrons shows the digital transitions. This paper presents designing of adder circuits in light of quantum-cellular automata (QCA) nanotechnology, which offers an approach to execute rationale and all interconnections with just a single homogeneous layer of cells. . The quantum-dot cellular automata (QCA) approach represents one of the possible solutions in overcoming this physical limit, even though the design of logic modules in QCA is not always straightforward. QCA adders are basic building blocks for larger QCA computational units. Our work shown comparative analysis for for different parameters like area, power consumption of 128 bit QCA ripple-carry adder and 128 bit carry-look-ahead adders designed with mg gates. The proposed 128 Bit QCA adder is implemented on Xilinx ISE and designed using Verilog HDL.

Keywords: QCA-quantum cellular automata, mg gates, nano technology.

Design and Optimization of Laminated Hybrid Composite Cylinder with Stiffeners Subjected to Buckling Load

Authors: S Giriprasad, Dr S Srinivasa Rao, Dr M K. Naidu

Abstract: Fibre Reinforced Polymer composite (FRPC) materials have wide applications in aircraft and automobile structures due to their high specific stiffness and strength properties. FRPC materials traditionally designed and manufactured as multiply laminates consists of several unidirectional layers resulting in a material with spatially uniform stiffness/strength properties. The fibre orientation angle in most of the applications typically held fixed and mostly limited to unidirectional. By limiting each layer to have a constant orientation angle over the entire structural component cannot fully make use of the directional material properties offered by composite layers. The laminated cylindrical shells are being used in submarine, underground mines, aerospace applications and other civil engineering applications. Buckling is also important factor to decide the failure of the structure. Pressure vessels, submarines and long columns will tend to buckle. To avoid the buckling failure, large amount of material will be used, it results the higher weight of the structure. Generally cylindrical shells such as pressure vessels are manufactured by steel alloys. In present days to reduce the weight of the structures, these are manufacturing by composite materials like carbon epoxy, Glass epoxy. This study aims to increase the design load of laminated composite FRP cylinder under buckling load. Initially a hybrid laminate designed in Ansys workbench by considering six ply angles with all fibres oriented at zero degrees. Response surface optimization used to obtain different optimized fibre orientations in a laminate by considering output parameters as deformation and Inverse Reserve factor. The optimized fibre angles are applied to the Ring stiffened cylinder. The configuration that gives higher load multiplier will attain higher load carrying capacity. Ring stiffened cylinder modelled and Analysis performed in ansys workbench and materials considered are Epoxy carbon and Epoxy S-Glass. The results are compared with theoretical calculations.

Keywords: Fibre Reinforced Polymer composite, Cylinder, Buckling Load

Fuzzy C – Means based Automatic Reference Color Selection of an Image

Authors: Sarika.Uma Maheswari, K.Harikadevi

Abstract: Here we propose a fuzzy c-means automatic reference color selection of an image for the adaptive mathematical morphology (MM) method, and is specifically designed for color image segmentation applications. Because of the main advantages of being simple, in the past decade, it has contributed to the growing popularity of binary and gray-scale MM processing. However, the MM process typically neglects the details of reference color determination. Applying other ordering methods, which select only black as the reference color for sorting pixels, result in the problem in which the scope of the distance measurement is not optimal. The proposed Fuzzy c-means algorithm is used for determining the ideal reference color for MM and color image segmentation application and can be used for cluster based color segmentation. Due to this segmentation rate will be comparatively higher.

Keywords: Adaptive mathematical morphology; Color image segmentation; Kernel density estimation; Reference color selection; Region growing; Region merging.

Area and Delay Optimized Arithmetic Architectures of VLSI for ACT Design

Authors: Aithi Vamsi Krishna, Niddana Prabha

Abstract: The discrete cosine transform (DCT) is a widely-used and important signal processing tool employed in a plethora of applications. Typical fast algorithms for nearly-exact computation of DCT require floating point arithmetic, are multiplier intensive, and accumulate round-off errors. Recently proposed fast algorithm arithmetic cosine transform (ACT) calculates the DCT exactly using only additions and integer constant multiplications, with very low area complexity, for null mean input sequences. The ACT can also be computed non-exactly for any input sequence, with low area complexity and low power consumption, utilizing the novel architecture described. However, as a trade-off, the ACT algorithm requires 10 non-uniformly sampled data points to calculate the eight-point DCT. This requirement can easily be satisfied for applications dealing with spatial signals such as image sensors and biomedical sensor arrays, by placing sensor elements in a non-uniform grid. In this work, a hardware architecture for the computation of the null mean ACT is proposed, followed by a novel architecture that extend the ACT for non-null mean signals. All circuits are implemented and tested and synthesized using the Xilinx ISE14.7.


PR Controller based VSC for FRT Enhancement of HVDC Distribution Network

Authors: Konada Naga Ravi Kumar, Meesala Shobha

Abstract: This paper proposes a changed current point of confinement methodology (MCLS) and a recurrence hysteresis control (FHC) for enhancing the aggravation ride-through capacity of a VSC-HVDC interface providing aloof mechanical establishments. Since mechanical burdens are more delicate to voltage drops than recurrence deviations, it's fundamental to ensure the solidness of voltage amid extreme flaws. The advancement of the control techniques incorporates three stages. To begin with, the fundamental component that influences the air conditioner voltage in the latent mechanical framework is broke down so as to upgrade the voltage solidness all the more adequately. Besides, as indicated by the scientific outcomes, the MCLS is proposed to build the air conditioner voltage in transient conditions. Thirdly, keeping in mind the end goal to improve the MCLS have a control result, the FHC is added to the VSC controller with the MCLS, which can likewise additionally upgrade the air conditioner voltage of the detached framework. The reenactment tests under metallic single-stage and three-stage deficiencies are done in PSCAD/EMTDC, and the outcomes check the legitimacy of the control strategies.

Keywords: PR Controller, passive industrial installations, voltage stability, Voltage Source Converter (VSC), modified current limit strategy, frequency hysteresis control, SVPWM.

Reversible Implementation of Ternary Content Addressable Memory (TCAM) Interface with SRAM

Authors: M.Sowjanya, Yelithoti Sravana Kumar

Abstract: Ternary content addressable memory is a special type of memory which is used to search for logic 0, logic 1, and logic 'x. TCAM finds the application in various fields. The main application of TCAM is found in the Network Routers where searching operation is done using the Contents. The other applications of the TCAM are found in Intrusion Detect, image processing, Gene pattern searching bioinformatics. These types of memory are used in routers in order to perform the lookup table function in a single clock cycle. As the use of networks, typified by the Internet, has spread widely in recent years, attention has focused on TCAMs asa key device for increasing the speed of packet forwarding (packet data transfers) by networking equipment by enabling high-speed lookup of destinations, etc., for large volumes of information during packet data transfers. Reversible logic has gained its interest in recent years due to its ultra low power characteristics. The proposed concept is designed using the reversible logic gate. In Reversible logic gates, each and every computed information is stored, because of that there is no loss of data and loss of power. There are equal number of inputs and outputs in reversible gates and the information is reused in the circuit by avoiding the loss of information by not computing the information computed before. In the proposed method the Ternary CAM with SRAM interface is implemented using the Reversible Toffoli gate in place of Peres gate and the Ternary CAM is implemented for 4x4 TCAM array, which is capable of searching data of 4 bit wide and it has 16 individual cells of TCAM.

Keywords: TCAM, Garbage output, Quantum cost, Reversible logic, Content addressable memory, Power consumption

Direct Torque Control of Brushless DC Motor with Non-sinusoidal Back-EMF

Authors: T.Vamsee Kiran, M.Sunil Kumar

Abstract: Abstract—In this paper, a direct torque control (DTC) technique for brushless dc (BLDC) motors with non-sinusoidal back-EMF operating in the constant torque region is presented. This approach introduces a two-phase conduction mode as opposed to the conventional three-phase DTC drives. In this control scheme, only two phases conduct at any instant of time. Unlike conventional six-step PWM current control, by properly selecting the inverter voltage space vectors of the two-phase conduction mode from a simple look-up table at a predefined sampling time, the desired quasi-square wave current is obtained. Therefore, a much faster torque response is achieved compared to conventional PWM current control. In this paper, it is also shown that in the constant torque region under the two-phase conduction DTC scheme, the amplitude of the stator flux linkage cannot easily be controlled due to the sharp changes and the curved shape of the flux vector between two consecutive commutation points in the stator flux linkage locus. Furthermore, to eliminate the low- frequency torque oscillations caused by the non-ideal trapezoidal shape of the actual back-EMF waveform of the BLDC motor, a pre-stored back-EMF versus position look-up table is designed. As a result, it is possible to achieve DTC of a BLDC motor drive with faster torque response due to the fact that the voltage space vectors are directly controlled while the stator flux linkage amplitude is deliberately kept almost constant by ignoring the flux control in the constant torque region. Since the flux control along with PWM generation is removed, fewer algorithms are required for the proposed control scheme. A theoretical concept is developed and the validity and effectiveness of the proposed DTC scheme are verified through the simulations and experimental results. Index Terms—Direct torque control, brushless dc motor drives, non-sinusoidal back-EMF, two-phase conduction, fast torque response, low-frequency torque ripples.

Keywords: Direct torque control, brushless dc motor drives, non-sinusoidal back-EMF, two-phase conduction, fast torque response, low-frequency torque ripples.

Harmonic reduction of non-inverting buck – boost dc/dc converter by introducing LC filters in network

Authors: V Vijaya Lakshmi, V Chennakesavulu

Abstract: This paper displays an execution of versatile double current mode control (ADCMC) on non-altering buck-support converter. A confirmation of the converter operation with the proposed ADCMC has been performed in consistent state and amid the unsettling influences in the information voltage and the heap resistance and by presenting LC channels. The given recreation with LC channel can give preferable execution over customary converter comes about.

Keywords: Digital controller, duty–discontinuity, mode-transition technique, non-inverting buck-boost converter

A new topology Based 13-Level inverter with various PWM Techniques

Authors: Crucypriya Darshnibhimala, N Balakrishna

Abstract: When contrasted with routine inverter topologies like diode clasped and capacitor cinched inverters, the cascaded multilevel inverter has lesser music and also lower switching stress. The fell topology has more number of power changes prompting more prominent warmth misfortunes, bigger size, higher cost and more door drive hardware. The proposed configuration contains less number of switches and creates lesser harmonics in the yield voltage than the fell topology. A comparison between four distinct sorts of heartbeat width regulation (PWM)techniques, to be specific, In-stage mien (IPD), Anti-phase disposition (APD), Carrier Overlap (CO) and Variable Frequency (VF) PWM strategies, has been finished. The outcomes have been checked through reproduction contemplate in MATLAB/Simulink in order to choose the best PWM technique that gives minimum THD in the yield voltage. A LC channel has been outlined to improve the consonant profile.

Keywords: Multilevel inverter, PWM procedure, add up to harmonic distortion, LC channel.

A Fuzzy based MMC STSTCOM for Enhance Dynamic behavior of the Network

Authors: P Rangababu, V Chennakesavalu

Abstract: A fuzzy based controller is proposed to control the voltage and current of the DC System. The voltage and current control loops are with fuzzy controller is monitor and control the error. The current loop control, a nonlinear controller based on the passivity based control theory is used in this cascaded structure STATCOM for the first time. The dc capacitor voltage control, overall voltage control is realized by adopting fuzzy controller. Clustered balancing control is obtained by using active disturbances rejection controller (ADRC). Individual balancing control is achieved by shifting the modulation wave vertically which can be easily implemented in FPGA .The proposed system is providing good dynamic performance while compared with the conventional STATCOM topology because of its robust procedure.

Keywords: Fuzzy logic controller, Cost-of-energy, DFIG, loss dissipation, reactive power.
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