Carlos J. Jiménez

Design and application of digital fuzzy controllers

This paper focuses on hardware implementations of fuzzy inference systems which provide low silicon cost, high operational speed and adaptability to different application domains. The architecture and basic building blocks of two fuzzy logic controllers are described and their functionality is illustrated with experimental results showing the capability of these systems to be applied as function approximators.

Xfuzzy: a design environment for fuzzy systems

Xfuzzy is a CAD tool that eases the development of fuzzy systems from their conception to their final implementation. It is composed of a set of modules and programs that share a common specification language and cover the different stages of the design process. Modules for describing, verifying and tuning the behavior of the system are integrated within the environment. In addition to these features, common to other fuzzy design tools, a relevant characteristic of Xfuzzy is that it includes several synthesis facilities for implementing the system on either software or hardware.

Prototyping of fuzzy logic-based controllers using standard FPGA development boards

This paper describes a design methodology for fuzzy logic-based control systems. The methodology employs hardware/software codesign techniques according to an a priori partition of the tasks assigned to the selected components. This feature makes it possible to tackle the control system prototyping as one of the design stages. In our case, the platform considered for prototyping has been a development board containing a standard microcontroller and an FPGA. Experimental results from an actual control application validate the efficiency of this methodology.

XFVHDL: a tool for the synthesis of fuzzy logic controllers

A tool for the synthesis of fuzzy controllers is presented in this paper. This tool takes as input the behavioral specification of a controller and generates its VHDL description according to a target architecture. The VHDL code can be synthesized by means of two implementation methodologies, ASIC and FPGA. The main advantages of using this approach are rapid prototyping, and the use of well-known commercial design environments like Synopsys, Mentor Graphics, or Cadence.

VHDL package for description of fuzzy logic controllers

The particular architecture of fuzzy systems has led to the introduction of specific simulators on the market, usually isolated from design environments. This article presents a VHDL package that allows high level descriptions and simulations of fuzzy controllers. The importance of this package to fuzzy hardware design lies not only in its portability to any VHDL simulator but also in that it allows verification of the simulation results of a particular system in a unique and standard simulation environment, from algorithm description level to RTL level (synthesizable) or logic gates. Finally, an example is included to demonstrate the package functionality.

A chromone from Zanthoxylum species

Abstract A new chromone was isolated from the bark of Zanthoxylum microcarpum and Z. valens and its structure determined by UV, IR, NMR and high resolution mass spectrometry as 5-hydroxy-7-methoxy-2-pentylchromone.

Hardware/software codesign methodology for fuzzy controller implementation

Describes a HW/SW codesign methodology for the implementation of fuzzy controllers on a platform composed of a general-purpose microcontroller and specific processing elements implemented on FPGAs or ASICs. The different phases of the methodology, as well as the CAD tools used in each design stage, are presented, with emphasis on the fuzzy system development environment Xfuzzy. Also included is a practical application of the described methodology for the development of a fuzzy controller for a dosage system.

Three phenylpropanoid glycosides from Mussatia

Abstract Three new phenylpropanoid glycosides, mussatioside I, mussatioside II and mussatioside III were isolated from the methanolic extract of the bark of a new Mussatia species. On the basis of the chemical and spectral evidence their structures were determined as [β-(4′-hydroxyphenyl)ethyl- O -β- D -glucopyranosyl(6 → 1)]- O -β- D -xylopyranosyl(1 → 3)-α- L -(4- O -t-cinnamoyl)rhamnopyranoside, [β-(4′-hydroxyphenyl)-ethyl- O -β- D -glucopyranosyl(6 → 1)]- O -β- D -xylopyranosyl(1 → 3)-α- L -(4- O -dimethylcaffeoyl)rhamnopyranoside and [β-(4′-hydroxyphenyl)ethyl- O -β- D -glucopyranosyl(6 → 1)]- O -β- D -xylopyranosyl(1 → 3)-α- L -(4- O - p -methylcoumaroyl)rhamnopyranoside, respectively. M. hyacinthina was also found to contain mussatioside I.

High radix implementation of Montgomery multipliers with CSA

Modular multiplication is the key operation in systems based on public key encryption, both for RSA and elliptic curve (ECC) systems. High performance hardware implementations of RSA and ECC systems use the Montgomery algorithm for modular multiplication, since it allows results to be obtained without performing the division operation. The aim of this article is to explore various modified structures of the Montgomery algorithm for high speed implementation. We present the implementation of a modified Montgomery algorithm with CSA and with different radix. In order to optimize the implementation regarding operation speed, we considered carry save adders structures and the Booth recoding scheme. The structure used in this paper simplifies the computation of the partial products avoiding the use of memories to store pre-calculated data for partial products which cannot be achieved by the shifting operation. The result shows that high-radix implementations are better for high speed applications.

A Programmable and Configurable ASIC to Generate Piecewise-Affine Functions Defined Over General Partitions

This paper presents a programmable and configurable architecture and its inclusion in an Application Specific Integrated Circuit (ASIC) to generate Piecewise-Affine (PWA) functions. A Generic PWA form (PWAG) has been selected for integration, because of its suitability to implement any PWA function without resorting to approximation. The design of the ASIC in a 90 nm TSMC technology, its integration, test and characterization through different examples are detailed in the paper. Furthermore, the ASIC verification using an ASIC-in-the-loop methodology for embedded control applications is presented. To assess the characteristics of this verification, the double-integrator, a usual control application example has been considered. Experimental results validate the proposed architecture and the ASIC implementation.