1 V CMOS subthreshold log domain PDM

A new CMOS circuit strategy for very low-voltage Pulse-Duration Modulators (PDM) is proposed. Optimization of voltage supply scaling below the sum of threshold voltages is based on Instantaneous Log Companding processing through the MOSFET operating in weak inversion. A 1 V VLSI PDM circuit for very low-voltage audio applications such as Hearing Aids is presented, showing good agreement between simulated and experimental data.Comisión Interministerial de Ciencia y Tecnología TIC97-1159, TIC99-1084European Union 2306

Novel active-compensated weighted summer

A summer amplifier with extended bandwidth is proposed. Compensation of the frequency characteristics is achieved by employing two operational amplifiers instead of external reactive components

On the Active Compensation of Operational Amplifier Based VCVS

A unified treatment of the active compensation for VCVS realized by operational amplifiers is presented. It is a summary of low-sensitivity circuit structures which can be either magnitude or phase compensated. The performance of such a circuits is discussed in detail. Experimental data for some of them are also included

Modeling of an aircraft fre extinguishing process with a porous medium equation.

The aim of this work is to provide a formulation of a non-linear difusion model in the form of a Porous Medium Equation (PME) with application to a fre extinguishing process in an aircraft engine nacelle. The work starts by describing some relevant publications currently related to fre suppression modelling methods with emphasis in the aerospace sector. The PME is then introduced highlighting some key relevant features (particularly the fnite speed of propagation) compared to the classical Heat Equation (HE). We will refer as u to the extinguisher or suppressor concentration in the media, which is postulated to be governed by a PME equation of the form: where Without losing generality and in virtue of the mass transfer application, we will consider that any solution is u ≥ 0. The set of equation and conditions expressed from (1) to (4) will be referred as problem P. From a mathematical perspective, the main areas of analysis are related to the existence of solutions, the obtaining of particular solutions as asymptotic approach and the application or particularization to a representative aircraft engine nacelle domain where a fre may happen.post-print3,45 M

Efficient state reduction methods for PLA-based sequential circuits

Experiences with heuristics for the state reduction of finite-state machines are presented and two new heuristic algorithms described in detail. Results on machines from the literature and from the MCNC benchmark set are shown. The area of the PLA implementation of the combinational component and the design time are used as figures of merit. The comparison of such parameters, when the state reduction step is included in the design process and when it is not, suggests that fast state-reduction heuristics should be implemented within FSM automatic synthesis systems

Efficient realization of a threshold voter for self-purging redundancy

The self-purging technique is not commonly used mainly due to the lack of practical implementations of its key component, the threshold voter. A very efficient implementation of this voter is presented which uses a decomposition technique to substantially reduce the circuit complexity and delay, as compared to alternative implementations.Comisión Interministerial de Ciencia y Tecnología TIC97-064

Dret i polítiques ambientals en la Comunitat Valenciana

El autor analiza principalmente la legislación de la Comunidad Valenciana relativa a espacios naturales y zonas de protección, y vedas y reservas de caza y pesca.L’autor analitza principalment la legislació de la Comunitat Valenciana relativa a espais naturals i zones de protección, i vedes i reserves de caça i pescaThe author focuses mainly on analysing the Valencian Community legislation on natural spaces and protection zones, as well as hunting and fishing closed seasons and reserves

La distribución competencial en materia de costas

Sobre la zona litoral hi ha una concurrència de competències que determina la necessitat d’integrar a la seva ordenació i gestió els interessos presents. Amb aquesta finalitat, la doctrina constitucional ha utilitzat els paràmetres de la cooperació i, si no n’hi havia, la determinació de la competència prevalent. En aquest context, l’ordenació del territori i del litoral per les comunitats autònomes, per les seves funcions de distribució d’usos i d’articulació de les visions sectorials i locals concurrents, es configura com l’instrument idoni per aconseguir-ne la gestió integral, que atengui tant la finalitats de la Llei de costes com els interessos autonòmics i municipals sobre aquesta. En aquest sentit, són diversos els títols estatals que condicionen aquesta competència autonòmica i que justifiquen el repartiment de funcions i les formes de col•laboració que preveu la Llei, entre els quals es poden considerar les facultats que deriven de la seva titularitat del domini, de la protecció del medi ambient litoral, la regulació de les condicions bàsiques per a l’exercici de drets i el compliment de deures constitucionals, i altres títols amb incidència sobre aquest espai.On the coastline, there is a conflict of powers which determines the need to coordinate existing interests in the planning and management of the coastal zone. For this reason, constitutional principles have employed cooperation parameters, and failing these, the prevailing competence has been determined. In this context, territorial and coastline planning by Spanish Autonomous Communities (AC) has been adopted as the ideal instrument to accomplish the coastline’s all-round management since AC decide on land use and coordinate sectorial and local competences. This instrument considers not only the objectives of the Coastal Law, but also the local and regional interests in it. In this sense, there are several state regulations that condition this regional competence and justify the assignment of tasks and the forms of collaboration as set out in the Law. Among them, it is necessary to consider the powers which are a result of the ownership of the domain, the protection of the coastal environment, the regulation of the basic conditions for the exercise of rights, the fulfilment of constitutional duties, and any other regulations which may affect this area.Sobre la zona litoral se da una concurrencia de competencias que determina la necesidad de integrar en su ordenación y gestión los intereses presentes. Para ello, la doctrina constitucional ha utilizado los parámetros de la cooperación y, en su defecto, la determinación de la competencia prevalente. En este contexto, la ordenación del territorio y del litoral por las Comunidades Autónomas, por sus funciones de distribución de usos y de articulación de las visiones sectoriales y locales concurrentes, se configura como el instrumento idóneo para lograr su gestión integral, que atienda tanto a la finalidades de la Ley de Costas como a los intereses autonómicos y municipales sobre la misma. En este sentido, son diversos los títulos estatales que condicionan esa competencia autonómica y que justifican el reparto de funciones y las formas de colaboración que prevé la Ley, entre los que cabe considerar las facultades que derivan de su titularidad del dominio, de la protección del medio ambiente litoral, la regulación de las condiciones básicas para el ejercicio de derechos y el cumplimiento de deberes constitucionales, y otros títulos con incidencia sobre este espacio

Benchmarking Particle Filter Algorithms for Efficient Velodyne-Based Vehicle Localization

Keeping a vehicle well-localized within a prebuilt-map is at the core of any autonomous vehicle navigation system. In this work, we show that both standard SIR sampling and rejection-based optimal sampling are suitable for efficient (10 to 20 ms) real-time pose tracking without feature detection that is using raw point clouds from a 3D LiDAR. Motivated by the large amount of information captured by these sensors, we perform a systematic statistical analysis of how many points are actually required to reach an optimal ratio between efficiency and positioning accuracy. Furthermore, initialization from adverse conditions, e.g., poor GPS signal in urban canyons, we also identify the optimal particle filter settings required to ensure convergence. Our findings include that a decimation factor between 100 and 200 on incoming point clouds provides a large savings in computational cost with a negligible loss in localization accuracy for a VLP-16 scanner. Furthermore, an initial density of ∼2 particles/m 2 is required to achieve 100% convergence success for large-scale (∼100,000 m 2 ), outdoor global localization without any additional hint from GPS or magnetic field sensors. All implementations have been released as open-source software

Travelling waves and instability in a Fisher-KPP problem with a non-linear advection and a high order diffusion.

pre-print594 K