554 research outputs found

    A Modular Programmable CMOS Analog Fuzzy Controller Chip

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    We present a highly modular fuzzy inference analog CMOS chip architecture with on-chip digital programmability. This chip consists of the interconnection of parameterized instances of two different kind of blocks, namely label blocks and rule blocks. The architecture realizes a lattice partition of the universe of discourse, which at the hardware level means that the fuzzy labels associated to every input (realized by the label blocks) are shared among the rule blocks. This reduces the area and power consumption and is the key point for chip modularity. The proposed architecture is demonstrated through a 16-rule two input CMOS 1-μm prototype which features an operation speed of 2.5 Mflips (2.5×10^6 fuzzy inferences per second) with 8.6 mW power consumption. Core area occupation of this prototype is of only 1.6 mm 2 including the digital control and memory circuitry used for programmability. Because of the architecture modularity the number of inputs and rules can be increased with any hardly design effort.This work was supported in part by the Spanish C.I.C.Y.T under Contract TIC96-1392-C02- 02 (SIVA)

    Electronic neuroprocessors

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    The JPL Center for Space Microelectronics Technology (CSMT) is actively pursuing research in the neural network theory, algorithms, and electronics as well as optoelectronic neural net hardware implementations, to explore the strengths and application potential for a variety of NASA, DoD, as well as commercial application problems, where conventional computing techniques are extremely time-consuming, cumbersome, or simply non-existent. An overview of the JPL electronic neural network hardware development activities and some of the striking applications of the JPL electronic neuroprocessors are presented

    VLSI Design

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    This book provides some recent advances in design nanometer VLSI chips. The selected topics try to present some open problems and challenges with important topics ranging from design tools, new post-silicon devices, GPU-based parallel computing, emerging 3D integration, and antenna design. The book consists of two parts, with chapters such as: VLSI design for multi-sensor smart systems on a chip, Three-dimensional integrated circuits design for thousand-core processors, Parallel symbolic analysis of large analog circuits on GPU platforms, Algorithms for CAD tools VLSI design, A multilevel memetic algorithm for large SAT-encoded problems, etc

    FPGA design methodology for industrial control systems—a review

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    This paper reviews the state of the art of fieldprogrammable gate array (FPGA) design methodologies with a focus on industrial control system applications. This paper starts with an overview of FPGA technology development, followed by a presentation of design methodologies, development tools and relevant CAD environments, including the use of portable hardware description languages and system level programming/design tools. They enable a holistic functional approach with the major advantage of setting up a unique modeling and evaluation environment for complete industrial electronics systems. Three main design rules are then presented. These are algorithm refinement, modularity, and systematic search for the best compromise between the control performance and the architectural constraints. An overview of contributions and limits of FPGAs is also given, followed by a short survey of FPGA-based intelligent controllers for modern industrial systems. Finally, two complete and timely case studies are presented to illustrate the benefits of an FPGA implementation when using the proposed system modeling and design methodology. These consist of the direct torque control for induction motor drives and the control of a diesel-driven synchronous stand-alone generator with the help of fuzzy logic

    Development of FPGA based Standalone Tunable Fuzzy Logic Controllers

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    Soft computing techniques differ from conventional (hard) computing, in that unlike hard computing, it is tolerant of imprecision, uncertainty, partial truth, and approximation. In effect, the role model for soft computing is the human mind and its ability to address day-to-day problems. The principal constituents of Soft Computing (SC) are Fuzzy Logic (FL), Evolutionary Computation (EC), Machine Learning (ML) and Artificial Neural Networks (ANNs). This thesis presents a generic hardware architecture for type-I and type-II standalone tunable Fuzzy Logic Controllers (FLCs) in Field Programmable Gate Array (FPGA). The designed FLC system can be remotely configured or tuned according to expert operated knowledge and deployed in different applications to replace traditional Proportional Integral Derivative (PID) controllers. This re-configurability is added as a feature to existing FLCs in literature. The FLC parameters which are needed for tuning purpose are mainly input range, output range, number of inputs, number of outputs, the parameters of the membership functions like slope and center points, and an If-Else rule base for the fuzzy inference process. Online tuning enables users to change these FLC parameters in real-time and eliminate repeated hardware programming whenever there is a need to change. Realization of these systems in real-time is difficult as the computational complexity increases exponentially with an increase in the number of inputs. Hence, the challenge lies in reducing the rule base significantly such that the inference time and the throughput time is perceivable for real-time applications. To achieve these objectives, Modified Rule Active 2 Overlap Membership Function (MRA2-OMF), Modified Rule Active 3 Overlap Membership Function (MRA3-OMF), Modified Rule Active 4 Overlap Membership Function (MRA4-OMF), and Genetic Algorithm (GA) base rule optimization methods are proposed and implemented. These methods reduce the effective rules without compromising system accuracy and improve the cycle time in terms of Fuzzy Logic Inferences Per Second (FLIPS). In the proposed system architecture, the FLC is segmented into three independent modules, fuzzifier, inference engine with rule base, and defuzzifier. Fuzzy systems employ fuzzifier to convert the real world crisp input into the fuzzy output. In type 2 fuzzy systems there are two fuzzifications happen simultaneously from upper and lower membership functions (UMF and LMF) with subtractions and divisions. Non-restoring, very high radix, and newton raphson approximation are most widely used division algorithms in hardware implementations. However, these prevalent methods have a cost of more latency. In order to overcome this problem, a successive approximation division algorithm based type 2 fuzzifier is introduced. It has been observed that successive approximation based fuzzifier computation is faster than the other type 2 fuzzifier. A hardware-software co-design is established on Virtex 5 LX110T FPGA board. The MATLAB Graphical User Interface (GUI) acquires the fuzzy (type 1 or type 2) parameters from users and a Universal Asynchronous Receiver/Transmitter (UART) is dedicated to data communication between the hardware and the fuzzy toolbox. This GUI is provided to initiate control, input, rule transfer, and then to observe the crisp output on the computer. A proposed method which can support canonical fuzzy IF-THEN rules, which includes special cases of the fuzzy rule base is included in Digital Fuzzy Logic Controller (DFLC) architecture. For this purpose, a mealy state machine is incorporated into the design. The proposed FLCs are implemented on Xilinx Virtex-5 LX110T. DFLC peripheral integration with Micro-Blaze (MB) processor through Processor Logic Bus (PLB) is established for Intellectual Property (IP) core validation. The performance of the proposed systems are compared to Fuzzy Toolbox of MATLAB. Analysis of these designs is carried out by using Hardware-In-Loop (HIL) test to control various plant models in MATLAB/Simulink environments

    Comparison between Frame-Constrained Fix-Pixel-Value and Frame-Free Spiking-Dynamic-Pixel ConvNets for Visual Processing

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    Most scene segmentation and categorization architectures for the extraction of features in images and patches make exhaustive use of 2D convolution operations for template matching, template search, and denoising. Convolutional Neural Networks (ConvNets) are one example of such architectures that can implement general-purpose bio-inspired vision systems. In standard digital computers 2D convolutions are usually expensive in terms of resource consumption and impose severe limitations for efficient real-time applications. Nevertheless, neuro-cortex inspired solutions, like dedicated Frame-Based or Frame-Free Spiking ConvNet Convolution Processors, are advancing real-time visual processing. These two approaches share the neural inspiration, but each of them solves the problem in different ways. Frame-Based ConvNets process frame by frame video information in a very robust and fast way that requires to use and share the available hardware resources (such as: multipliers, adders). Hardware resources are fixed- and time-multiplexed by fetching data in and out. Thus memory bandwidth and size is important for good performance. On the other hand, spike-based convolution processors are a frame-free alternative that is able to perform convolution of a spike-based source of visual information with very low latency, which makes ideal for very high-speed applications. However, hardware resources need to be available all the time and cannot be time-multiplexed. Thus, hardware should be modular, reconfigurable, and expansible. Hardware implementations in both VLSI custom integrated circuits (digital and analog) and FPGA have been already used to demonstrate the performance of these systems. In this paper we present a comparison study of these two neuro-inspired solutions. A brief description of both systems is presented and also discussions about their differences, pros and cons

    Applications and implementation of neuro-connectionist architectures.

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    by H.S. Ng.Thesis (M.Phil.)--Chinese University of Hong Kong, 1996.Includes bibliographical references (leaves 91-97).Chapter 1 --- Introduction --- p.1Chapter 1.1 --- Introduction --- p.1Chapter 1.2 --- Neuro-connectionist Network --- p.2Chapter 2 --- Related Works --- p.5Chapter 2.1 --- Introduction --- p.5Chapter 2.1.1 --- Kruskal's Algorithm --- p.5Chapter 2.1.2 --- Prim's algorithm --- p.6Chapter 2.1.3 --- Sollin's algorithm --- p.7Chapter 2.1.4 --- Bellman-Ford algorithm --- p.8Chapter 2.1.5 --- Floyd-Warshall algorithm --- p.9Chapter 3 --- Binary Relation Inference Network and Path Problems --- p.11Chapter 3.1 --- Introduction --- p.11Chapter 3.2 --- Topology --- p.12Chapter 3.3 --- Network structure --- p.13Chapter 3.3.1 --- Single-destination BRIN architecture --- p.14Chapter 3.3.2 --- Comparison between all-pair BRIN and single-destination BRIN --- p.18Chapter 3.4 --- Path Problems and BRIN Solution --- p.18Chapter 3.4.1 --- Minimax path problems --- p.18Chapter 3.4.2 --- BRIN solution --- p.19Chapter 4 --- Analog and Voltage-mode Approach --- p.22Chapter 4.1 --- Introduction --- p.22Chapter 4.2 --- Analog implementation --- p.24Chapter 4.3 --- Voltage-mode approach --- p.26Chapter 4.3.1 --- The site function --- p.26Chapter 4.3.2 --- The unit function --- p.28Chapter 4.3.3 --- The computational unit --- p.28Chapter 4.4 --- Conclusion --- p.29Chapter 5 --- Current-mode Approach --- p.32Chapter 5.1 --- Introduction --- p.32Chapter 5.2 --- Current-mode approach for analog VLSI Implementation --- p.33Chapter 5.2.1 --- Site and Unit output function --- p.33Chapter 5.2.2 --- Computational unit --- p.34Chapter 5.2.3 --- A complete network --- p.35Chapter 5.3 --- Conclusion --- p.37Chapter 6 --- Neural Network Compensation for Optimization Circuit --- p.40Chapter 6.1 --- Introduction --- p.40Chapter 6.2 --- A Neuro-connectionist Architecture for error correction --- p.41Chapter 6.2.1 --- Linear Relationship --- p.42Chapter 6.2.2 --- Output Deviation of Computational Unit --- p.44Chapter 6.3 --- Experimental Results --- p.46Chapter 6.3.1 --- Training Phase --- p.46Chapter 6.3.2 --- Generalization Phase --- p.48Chapter 6.4 --- Conclusion --- p.50Chapter 7 --- Precision-limited Analog Neural Network Compensation --- p.51Chapter 7.1 --- Introduction --- p.51Chapter 7.2 --- Analog Neural Network hardware --- p.53Chapter 7.3 --- Integration of analog neural network compensation of connectionist net- work for general path problems --- p.54Chapter 7.4 --- Experimental Results --- p.55Chapter 7.4.1 --- Convergence time --- p.56Chapter 7.4.2 --- The accuracy of the system --- p.57Chapter 7.5 --- Conclusion --- p.58Chapter 8 --- Transitive Closure Problems --- p.60Chapter 8.1 --- Introduction --- p.60Chapter 8.2 --- Different ways of implementation of BRIN for transitive closure --- p.61Chapter 8.2.1 --- Digital Implementation --- p.61Chapter 8.2.2 --- Analog Implementation --- p.61Chapter 8.3 --- Transitive Closure Problem --- p.63Chapter 8.3.1 --- A special case of maximum spanning tree problem --- p.64Chapter 8.3.2 --- Analog approach solution for transitive closure problem --- p.65Chapter 8.3.3 --- Current-mode approach solution for transitive closure problem --- p.67Chapter 8.4 --- Comparisons between the different forms of implementation of BRIN for transitive closure --- p.71Chapter 8.4.1 --- Convergence Time --- p.71Chapter 8.4.2 --- Circuit complexity --- p.72Chapter 8.5 --- Discussion --- p.73Chapter 9 --- Critical path problems --- p.74Chapter 9.1 --- Introduction --- p.74Chapter 9.2 --- Problem statement and single-destination BRIN solution --- p.75Chapter 9.3 --- Analog implementation --- p.76Chapter 9.3.1 --- Separated building block --- p.78Chapter 9.3.2 --- Combined building block --- p.79Chapter 9.4 --- Current-mode approach --- p.80Chapter 9.4.1 --- "Site function, unit output function and a completed network" --- p.80Chapter 9.5 --- Conclusion --- p.83Chapter 10 --- Conclusions --- p.85Chapter 10.1 --- Summary of Achievements --- p.85Chapter 10.2 --- Future development --- p.88Chapter 10.2.1 --- Application for financial problems --- p.88Chapter 10.2.2 --- Fabrication of VLSI Implementation --- p.88Chapter 10.2.3 --- Actual prototyping of Analog Integrated Circuits for critical path and transitive closure problems --- p.89Chapter 10.2.4 --- Other implementation platform --- p.89Chapter 10.2.5 --- On-line update of routing table inside the router for network com- munication using BRIN --- p.89Chapter 10.2.6 --- Other BRIN's applications --- p.90Bibliography --- p.9
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