SMT proof checking using a logical framework

Producing and checking proofs from SMT solvers is currently the most feasible method for achieving high confidence in the correctness of solver results. The diversity of solvers and relative complexity of SMT over, say, SAT means that flexibility, as well as performance, is a critical characteristic of a proof-checking solution for SMT. This paper describes such a solution, based on a Logical Framework with Side Conditions (LFSC). We describe the framework and show how it can be applied for flexible proof production and checking for two different SMT solvers, clsat and cvc3. We also report empirical results showing good performance relative to solver execution time.     

Effect of deep-trap level on transverse acoustoelectric voltage measurements

The effect of trapped charges on the transverse acoustoelectric voltage (TAV) is investigated with the aim of extending the use of TAV measurements to the study of semiconductors with high defect density. Even if surface acoustic wave frequencies are as high as 100 MHz, charge trapping can influence the TAV. This has been verified by two particular experiments performed on Si/SiO(2) structures with high density of interface states. A theoretical model is proposed to explain the effects of the presence of deep-trap levels on the TAV. Novel boundary conditions for the acoustoelectric equations are introduced and an approximate solution for the TAV amplitude is presented. The model is used to define a novel procedure for the determination of interface-states' density using TAV versus bias voltage measurements.     

Highly reliable and high-yield 1300-nm InGaAlAs directly modulated ridge fabry-Perot lasers, operating at 10-gb/s, up to 110/spl deg/C, with constant current swing

Transceivers for 300-m multimode links, based on a serial 10-Gb/s laser source and incorporating a receiver based on electronic dispersion compensation (EDC), are creating the first high-volume application for a 10-Gb Fabry-Perot (FP). A highly reliable and high-yield uncooled ridge FP laser is presented. The device shows excellent power characteristics in the 25/spl divide/150/spl deg/C temperature range with very high T/sub 0/ (95 K in the temperature range 0/spl divide/85/spl deg/C and still 78 K at 150/spl deg/C). Outstanding dynamic performances are also shown: 6 dB of extinction ratio can be achieved up to 110/spl deg/C by using a constant current swing of 50 mA. Because of their enhanced performances, these devices have enabled single temperature setting of the optical module, leading to a significant test cost reduction.     

Humidity‐Driven Mechanical and Electrical Response of Graphene/Cloisite Hybrid Films

Humidity‐driven and electrically responsive graphene/cloisite hybrid films are obtained by casting water dispersions of graphene oxide and cloisite Na⁺. Coupling hydrophilicity and a high water vapor barrier in a homogenous film enables to realize humidity‐driven actuators which exploit the water gradient generated across the film section under asymmetric exposure to humidity. The hybrid films are self‐standing, flexible, and exhibit fast humidity‐triggered bidirectional bending up to 75°, which is tuned by varying the relative amount of the two components. Up to 60% of the bending angle can be preserved at the steady state, providing a large and reliable response to humidity. Moreover, thermal treatment results in the reduction of graphene oxide, endowing the films with humidity‐dependent electrical conductivity, which increases from 1.5 × 10^?6 S at 20% relative humidity (RH) up to 2.7 × 10^?5 S at 90% RH. The films are used to realize a humidity‐sensitive electrical switching system in which the reversible actuation is due to water desorption induced by the Joule effect. Due to their ease of preparation and tunable properties, this new class of graphene‐based materials is suitable for the realization of humidity‐driven and electrically responsive actuators and sensors.     

Actinides AMS at CIRCE in Caserta (Italy)

The operation of Nuclear Power Plants and atmospheric tests of nuclear weapons performed in the past, together with production, transport and reprocessing of nuclear fuel, lead to the release into the environment of a wide range of radioactive nuclides, such as uranium, plutonium, fission and activation products. These nuclides are present in the environment at ultra trace levels. Their detection requires sensitive techniques like AMS (Accelerator Mass Spectrometry). In order to perform isotopic ratio measurements of the longer-lived actinides, e.g., of ²³⁶U relative to the primary ²³⁸U and various Pu isotopes relative to ²³⁹Pu, an upgrade of the CIRCE accelerator (Center for Isotopic Research on Cultural and Environmental Heritage) in Caserta, Italy, is underway. In this paper we report on the results of simulations aiming to define the best ion optics and to understand the origin of possible measurement background. The design of a high resolution TOF-E (Time of Flight-Energy) detector system is described, which will be used to identify the rare isotopes among interfering background signals.     

Kawashima condition and acceleration waves for binary nonreacting mixtures

Summary The existence of global smooth solutions for a binary nonreacting mixture of Grad type is proved by using the Kawashima condition. The propagation of acceleration waves is also investigated. The characteristic speeds and the amplitude equation are derived.     

Determination of the oil content in olives by the DSC technique

Differential scanning calorimetry (DSC) has been used to determine the oil content in dried olive pulp of Cassanese and Carolea tree cultivars and to follow their inoliation trends from September to January. DSC was performed by cooling samples of olive dried pulp from -10 to -60vv°C at 1vv°C/min and the amount of oil calculated from the peak area obtained. The enthalpy and temperature range of the crystallization peak for the pure oil were 61 J/g and -34 to -40vv°C for the first cultivar and 54 J/g and -35 to -42vv°C for the second one. The proposed DSC method is fast, specific, and reliable. It does not use solvents, requires smaller samples (<100 mg) than conventional solvent methods, and can detect real absence of water in the sample.     

Effects of distillery vinasses on vineyard yield and quality in the D.O.C "Oltrepò Pavese Pinot Nero"--Lombardy, Italy.

In a fifteen year old vineyard of Pinot Noir at a density of 5000 vines per hectares, located in the DOC zone Oltrepò Pavese, the influence of growing doses of distillery vinasses on vegetative growth, leaf mineral levels, grape yield and quality was tested in a four year period. Doses of vinasses were computed to apply 0 (test), 50, 100, 150 kg N ha(-1). Vinasses doses were factorially combined with three levels of urea (0, 50 and 100 kg N ha(-1)). In plots without vinasses supply, ureic nitrogen reduced the number of blind buds and increased the potential and actual bud fertility. The application of vinasses nitrogen had a similar result, even if ureic and vinasses nitrogen had no additive effects. The most profitable grape yield was obtained by application of 50 kg ha(-1) of nitrogen either in urea or in vinasses form. Highest vinasses supply improved the ripening levels of grapes increasing sugars and reducing acidity of juice. Results clearly show the possibility to use vinasses for proper vineyard fertilisation.     

Iterative multiuser detection, macrodiversity combining, anddecoding for the TDMA cellular uplink

A soft-input soft-output (SISO) multiuser detector (MUD) suitable for inclusion in iterative processing architectures is presented and applied to the detection of the coded time division multiple access (TDMA) cellular uplink. A SISO-MUD processor is located at each base station in the network, and adjacent base stations share information concerning the mobiles they serve. Because the MUD outputs are soft, they are suitable for postdetection macrodiversity combining. The combined signals are then passed to a SISO forward error correction (FEC) decoder, and the soft outputs are fed back to the multiuser detectors. Processing continues in an iterative fashion in accordance with the turbo principle. Simulation results are presented that indicate that use of such a scheme enables cellular systems to be overloaded with more than just one cochannel user per cell at the price of a minimal loss in signal-to-noise ratio (SNR). The proposed implementation assumes the availability of both perfect channel state information and a high capacity backhaul