A. Costa

Bio: A. Costa is an academic researcher from University of São Paulo. The author has contributed to research in topics: Fuzzy electronics & Fuzzy logic. The author has an hindex of 6, co-authored 7 publications receiving 184 citations.

Hardware solutions for fuzzy control

Abstract: A large fraction of software designs using microcontrollers is today adopting fuzzy logic algorithms and this fraction is likely to increase in the future. Hardware implementation of fuzzy logic ranges from standard microprocessors to dedicated ASICs and each different approach is targeted to a different application domain or market area. In this paper, we present an overview of the computational complexity of the fuzzy inference process and the various techniques adopted for fuzzy control tasks, highlighting the tradeoffs that can guide a system designer toward correct choices according to application features and cost/performance issues. In addition, we detail three case studies of architectures that address three different market segments in the fuzzy hardware scenario: dedicated fuzzy coprocessors, RISC processors with specialized fuzzy support and application specific fuzzy ASICs. >

Fuzzy logic microcontroller

Abstract: We propose an architecture dedicated mainly to medium-range applications that demand computational power combined with low cost for the resulting hardware system (chip and board). Our architecture is a 16-bit processor with dedicated instructions and hardware for efficient support of fuzzy logic. To make the architecture effective for control applications developed with a traditional approach or with fuzzy logic, we equipped the processor with a microcontroller's general features. Our design accounts for application characteristics to provide efficient hardware support for fuzzy logic. To achieve this we first analyzed fuzzy control algorithms and derived a general model for fuzzy computation. In defining the model, we considered the large spectrum of possible inference methods, fuzzification and defuzzification mechanisms, and the operators used in control applications. On this basis, we defined the instruction set that supports this computational model and a proper architectural solution. We tested the system (composed of the software model and its hardware support) by simulating different sets of general-purpose and fuzzy control benchmarks.

A VLSI architecture for hierarchical motion estimation

Abstract: Motion estimation is the critical path in compression algorithms, and several dedicated hardware solutions have been proposed for its acceleration. In this paper we present an innovative VLSI architecture for motion estimation that combines a low implementation cost with real-time performance for videoconferencing and DTV standards. To minimize computational load and architecture requirements, we adopt a three-step hierarchical search algorithm, that provides a quality comparable with more expensive full-search techniques. The proposed solution focuses on architectural efficiency by employing a minimum set of functional units (three simple processing units, one minimum unit, and four programmable delay lines), still supporting real-time performance for videoconferencing standards. In addition we show how to combine parallel motion estimation units for backward-forward prediction (MPEG) and for higher throughput standards (DTV). >

Hardware design of asynchronous fuzzy controllers

Abstract: This paper presents a hardware approach to the design of fuzzy controllers which, by exploiting some peculiar characteristics of fuzzy logic computation, allows one to save power consumption and increase computing speed. We show that the computation involved in a fuzzy controller has some statistic features that can be exploited by asynchronous computation. This paper presents a quantitative study of the statistical properties of fuzzy computation. A design methodology is introduced, and two experimental applications are shown.

An optimized RISC instruction set for fuzzy applications

Abstract: Presents a general purpose RISC instruction set with specific support for fuzzy logic. The authors show the design methodology, the processor architecture and its performance with respect to other fuzzy processors. Tests show a remarkable advantage over other realizations. These results have been achieved by means of a particularly suited instruction set and special optimizations in the compilation task. >

FPGA Implementation of Embedded Fuzzy Controllers for Robotic Applications

Abstract: Fuzzy-logic-based inference techniques provide efficient solutions for control problems in classical and emerging applications. However, the lack of specific design tools and systematic approaches for hardware implementation of complex fuzzy controllers limits the applicability of these techniques in modern microelectronics products. This paper discusses a design strategy that eases the implementation of embedded fuzzy controllers as systems on programmable chips. The development of the controllers is carried out by means of a reconfigurable platform based on field-programmable gate arrays. This platform combines specific hardware to implement fuzzy inference modules with a general-purpose processor, thus allowing the realization of hybrid hardware/software solutions. As happens to the components of the processing system, the specific fuzzy elements are conceived as configurable intellectual property modules in order to accelerate the controller design cycle. The design methodology and tool chain presented in this paper have been applied to the realization of a control system for solving the navigation tasks of an autonomous vehicle.

A survey of recent advances in fuzzy logic in telecommunications networks and new challenges

Abstract: The use of fuzzy logic in telecommunication systems and networks is recent and limited. Fundamentally, Zadeh's fuzzy set theory provides a robust mathematical framework for dealing with "real-world" imprecision and nonstatistical uncertainty. Given that the present day complex networks are dynamic, that there is great uncertainty associated with the input traffic and other environmental parameters, that they are subject to unexpected overloads, failures and perturbations, and that they defy accurate analytical modeling, fuzzy logic appears to be a promising approach to address many important aspects of networks. This paper reviews the current research efforts in fuzzy logic-based approaches to queuing, buffer management, distributed access control, load management, routing, call acceptance, policing, congestion mitigation, bandwidth allocation, channel assignment, network management, and quantitative performance evaluation in networks. The review underscores the future potential and promise of fuzzy logic in networks. The paper then presents a list of key research efforts in the areas of fuzzy logic-based algorithms and new hardware and software architectures that are necessary both to address new challenges in networking and to help realize the full potential of fuzzy logic in networks.

Fuzzy Logic for Embedded Systems Applications

Abstract: Fuzzy Logic for Embedded Systems Applications, by a recognized expert in the field, covers all the basic theory relevant to electronics design, with particular emphasis on embedded systems, and shows how the techniques can be applied to shorten design cycles and handle logic problems that are tough to solve using conventional linear techniques. All the latest advances in the field aree discussed and practical circuit design examples presented.Fuzzy logic has been found to be particularly suitable for many embedded control applications. The intuitive nature of the fuzzy-based system design saves engineers time and reduces costs by shortening product development cycles and making system maintenance and adjustments easier. Yet despite its wide acceptance—and perhaps because of its name—it is still misunderstood and feared by many engineers. There is a need for embedded systems designers—both hardware and software—to get up to speed on the principles and applications of fuzzy logic in order to ascertain when and how to use them appropriately.Fuzzy Logic for Embedded Systems Applications provides practical guidelines for designing electronic circuits and devices for embedded systems using fuzzy-based logic. It covers both theory and applications with design examples.

Healthcare facilities management: state of the art review

Abstract: Following increases in national demands on healthcare facilities and services, healthcare facilities management (FM) has gradually matured to become an established research and development topic. This paper reviews the state of the art in the main domains related to healthcare FM and defines the central themes in the development of a healthcare FM model. FM, maintenance management and performance management are reviewed in a wider context, and the main domains of healthcare FM are discussed. The five salient topics included in healthcare FM are maintenance management, performance management, risk management, supply services management, and development. These five core domains are interrelated, and can be integrated using information and communications technology, which provides the desired environment required for the challenging decision making and development prevalent in healthcare FM.

Segmented picture coding method and system, and corresponding decoding method and system

Abstract: The invention relates to a method and system for coding segmented pictures, and to corresponding decoding method and system. In the coding system, a first sub-system defines the time evolution of said segmented pictures, or partitions, and a second one encodes both contours and textures of the regions of the successive partitions. The time evolution definition leads to a partition tree (PT) from which regions are extracted during an analysis step (AS) in order to form a decision tree (DT). A decision operation allows to select during a choice step (CS) distinct regions RS from various levels of said partition tree, in order to construct an optimal final partition (BFP) and, simultaneously, to choose the coding technique (BCT) that is the best one for each region of said optimal partition. Reciprocally the decoding method and system comprise means for defining the coding strategy chosen for each of said regions and decoding correspondingly the coded information.