Cuckoo search (CS) is a recent swarm intelligence-based meta-heuristic optimisation algorithm that has shown excellent results for a broad class of optimisation problems in diverse fields. However, CS is generally com...
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Cuckoo search (CS) is a recent swarm intelligence-based meta-heuristic optimisation algorithm that has shown excellent results for a broad class of optimisation problems in diverse fields. However, CS is generally compute intensive and slow when implemented in software requiring large number of fitness function evaluations to obtain acceptable solutions. In this study, the authors present a problem specific parallel pipelined field programmable gate array-based accelerator to reduce execution time when solving complex optimisation problems. Experiments conducted on a large number of well-known benchmark functions revealed that the hardware approach offers a promising average speedup of 75x and 53x than software and GPU implementations, respectively.
This paper presents the design and testing of a newly developed field programmable gate array (FPGA) board for mobile robot research. The idea consists of interfacing the FPGA to a 16-bit digital signal controller (ds...
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This paper presents the design and testing of a newly developed field programmable gate array (FPGA) board for mobile robot research. The idea consists of interfacing the FPGA to a 16-bit digital signal controller (dsPIC). This idea enables the FPGA designs to communicate with the dsPIC through the integration of per-written driver modules to be used in a wide variety of digital and analog peripheral modules. It also allows the use of a high-performance digital signal processing core in many signal processing-based mobile robot applications. The proposed FPGA board allows users to develop, test, and deploy quick and cost-effective complete design solutions to control the entire robot system in various applications without the need for external components.
Point multiplication is required in every elliptic curve cryptosystem and its efficient implementation is essential. Koblitz curves are a family of curves defined over F-2m. allowing notably faster computation. We dis...
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Point multiplication is required in every elliptic curve cryptosystem and its efficient implementation is essential. Koblitz curves are a family of curves defined over F-2m. allowing notably faster computation. We discuss implementation of point multiplication on Koblitz curves with parallel field multipliers. We present a novel parallelization method utilizing point operation interleaving. FPGA implementations are described showing the practical feasibility of our method. They compute point multiplications on average in 4.9 mu s, 8.1 mu s, and 12.1 mu s on the standardized curves NIST K-163, K-233, and K-283, respectively, in an Altera Stratix II FPGA. (C) 2008 Elsevier B.V. All rights reserved.
A small-scale electric model vehicle is built with four in-wheel motors. A field programmable gate array is chosen as the control kernel for this electric vehicle system. Since this electric model vehicle has four in-...
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A small-scale electric model vehicle is built with four in-wheel motors. A field programmable gate array is chosen as the control kernel for this electric vehicle system. Since this electric model vehicle has four in-wheel driving motors without differential mechanism, it needs an electronic differential and well-designed control algorithm to manipulate the vehicle driving speed and orientation. Accurate mathematical model of this multi-input and multi-output electric vehicle system is difficult to establish for a model-based controller design. Here, the adaptive functional approximation control scheme is first employed to design the speed controller of each wheel for integrating with the Ackermann-Jeantand model-based electronic differential. A model reference adaptive-proportional-integral-derivative control is designed to manipulate the vehicle steering system. The experimental results show that the proposed adaptive functional approximation control and model reference adaptive-proportional-integral-derivative controllers can effectively monitor the wheel rotational speed and steering angle with rotational speed error and angular error less than 2r/min and 0.03 degrees, respectively. The induced electronic differential model successfully assisted the vehicle turning control and trajectory following control operations.
This paper describes the experimental performance of eigenbeam multi-input multi-output with orthogonal frequency division multiplexing (MIMO-OFDM) systems as measured in a testbed implemented with fieldprogrammable ...
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This paper describes the experimental performance of eigenbeam multi-input multi-output with orthogonal frequency division multiplexing (MIMO-OFDM) systems as measured in a testbed implemented with field programmable gate arrays (FPGAs). The FPGA-testbed, characterized by the software-defined radio (SDR) technique, offers 1/5-scale real time signal processing. Extensive experiments on the testbed confirm the basic operation and performance of eigenbeam, MIMO-OFDM with quadrature phase-shift keying (QPSK) and 16 quadrature amplitude modulation (QAM). From the packet error rate (PER) performance, we confirm that the eigenbeam 16QAM/MIMO-OFDM scheme with permutation matrix and three transmit antennas (M-t = 3) drastically improves the required carrier-to-noise power ratio (CNR) by approximately 5.6 dB over the scheme without eigenbeam with M-t = 2. Furthermore, to determine the impact of Doppler frequency f(d), we focus on the transmission interval between the MIMO channel estimation and data transmission. To suppress the required CNR degradation to within 1.5 dB, it is found that the eigenbeam 16QAM/MIMO-OFDM scheme with permutation matrix and M-t = 3 permits a transmission interval of approximately 68.5 ms when f(d) = 1 Hz for a 1/5-scale model.
This paper presents an application of model predictive control to the attitude dynamics of an underactuated spacecraft with two reaction wheels and zero angular momentum. Such a system cannot be stabilized by any smoo...
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This paper presents an application of model predictive control to the attitude dynamics of an underactuated spacecraft with two reaction wheels and zero angular momentum. Such a system cannot be stabilized by any smooth or continuous time-invariant feedback law. However, model predictive control has a remarkable ability to generate control laws that are discontinuous in the state and, as such, can be applied to this problem. The model predictive control formulation is analyzed in depth and shown to produce an asymptotically stabilizing controller, which is discontinuous and enforces constraints. Simulations on the full nonlinear model demonstrate that model predictive control can successfully control the attitude of an underactuated spacecraft when the attitude maneuvers are sufficiently small.
An electronic system for the real-time denoising of fluoroscopic images is proposed in this paper. Fluoroscopic devices use X-rays to obtain real-time moving images of patients and support many surgical interventions ...
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An electronic system for the real-time denoising of fluoroscopic images is proposed in this paper. Fluoroscopic devices use X-rays to obtain real-time moving images of patients and support many surgical interventions and a variety of diagnostic procedures. In order to avoid risks for the patient, X-ray intensity has to be kept acceptably low during the clinical applications. This implies that fluoroscopic images are corrupted by large quantum noise (Poisson-distributed). Real-time noise reduction can offer a better visual perception to doctors and possible further reductions of the dose. The proposed circuit implements a spatio-temporal filter optimized for the removal of the quantum noise while preserving video edges and the prompt response of the image to the introduction of new features in the field. The filter incorporates information on the dependence of the standard deviation of the noise on the local brightness of the image and performs a conditioned average operation. The proposed circuit is implemented on FPGA (field programmable gate array) device allowing the real time elaboration of video streams composed by frames with 1024 x 1024 pixel and uses an external DDR2 (Double Data Rate 2) memory for the storage and the reuse of the fluoroscopic frames needed by the filter. When implemented on StratixIV-GX70 FPGA the circuit is able to process up to 49 fps (frames per second) while using 80% of the logic resources of the FPGA. (C) 2014 Elsevier B.V. All rights reserved.
Solder joint resistance monitoring is important for electronic system prognostics and system health management. It is noted that the typical built-in self-test method of field programmable gate array (FPGA) solder joi...
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Solder joint resistance monitoring is important for electronic system prognostics and system health management. It is noted that the typical built-in self-test method of field programmable gate array (FPGA) solder joint based on charging and discharging of single capacitance has two main shortcomings of large power consumption and unavailability of the monitored pins in FPGA's functional design. In order to overcome these drawbacks, we propose an online measure method of FPGA solder joint resistance with the constraints of limited pin number and low power consumption in this paper. The model of our method is presented in detail, including external test circuit, internal test IP core and parameter determination. The validity of our proposal with low power consumption is upheld by theoretical studies. Furthermore, the corresponding platform of the novel method is built based on a Xilinx Spartan 6 FPGA, and the relative experiments are conducted. Meanwhile, the experiment results show that the method can be used to online measure the resistance of the solder joint of FPGA with lower power consumption than the typical built-in self-test method. (C) 2015 Elsevier Ltd. All rights reserved.
This brief presents an efficient architecture design for elementary-check-node processing in nonbinary low-density parity-check decoders based on the extended min-sum algorithm. This architecture relies on a simplifie...
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This brief presents an efficient architecture design for elementary-check-node processing in nonbinary low-density parity-check decoders based on the extended min-sum algorithm. This architecture relies on a simplified version of the bubble check algorithm and is implemented by the means of first-in-first-out. The adoption of this new design at the check node level results in a high-rate low-cost full-pipelined processor. A proof-of-concept implementation of this processor shows that the proposed architecture halves the occupied the field-programmablegatearray (FPGA) surface and doubles the maximum frequency without modifying the input/output behavior of the previous one.
The amount of noise present in the Fiber Optic Gyroscope (FOG) signal limits its applications and has a negative impact on navigation system. Existing algorithms such as Discrete Wavelet Transform (DWT), Kalman Filter...
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The amount of noise present in the Fiber Optic Gyroscope (FOG) signal limits its applications and has a negative impact on navigation system. Existing algorithms such as Discrete Wavelet Transform (DWT), Kalman Filter (KF) denoise the FOG signal under static environment, however denoising fails in dynamic environment. Therefore in this paper an Adaptive Moving Average Dual Mode Kalman Filter (AMADMKF) is developed for denoising the FOG signal under both the static and dynamic environments. Performance of the proposed algorithm is compared with DWT and KF techniques. Further, a hardware Intellectual Property (IP) of the algorithm is developed for System on Chip (SoC) implementation using Xilinx Virtex-5 field programmable gate array (Virtex-5FX70T-1136). The developed IP is interfaced as a Co-processor/ Auxiliary Processing Unit (APU) with the PowerPC (PPC440) embedded processor of the FPGA. It is proved that the proposed system is an efficient solution for denoising the FOG signal in real-time environment. Hardware acceleration of developed Co-processor is 65x with respect to its equivalent software implementation of AMADMKF algorithm in the PPC440 embedded processor. (C) 2013 Elsevier Inc. All rights reserved.
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