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This systematic review addressed the following question: Which are the relations between L1 and/or L2 foundational and upper-level language skills, cognitive skills, high-order cognitive and self-regulation factors and L2-English reading comprehension skills in 11-to-19 year EFL secondary school students with different L1 language profiles? Following preferred reporting items for systematic reviews and meta-analyses guidelines, twenty-seven studies were included for a systematic synthesis of results in the light of the different grades of "family language distance" between L1 and L2-English (i.e., "close related" vs. "partially related" vs. "not related"). We found that several L1 and L2 language skills (e.g., vocabulary, morphological awareness), cognitive skills (e.g., working memory) and high-order factors as metacognitive knowledge were positively associated with L2-English reading comprehension, regardless of different language groups. Conversely, we found that several well-known predictors of text comprehension are neglected in the scientific literature on reading in L2. We discuss practical implications and key recommendations to support school and future research. [ABSTRACT FROM AUTHOR]

In modern railway automatic train protection and automatic train control systems, odometry is a safety relevant on-board subsystem which estimates the instantaneous speed and the travelled distance of the train; a high reliability of the odometry estimate is fundamental, since an error on the train position may lead to a potentially dangerous overestimation of the distance available for braking. To improve the odometry estimate accuracy, data fusion of different inputs coming from a redundant sensor layout may be used. The aim of this work has been developing an innovative localisation algorithm for railway vehicles able to enhance the performances, in terms of speed and position estimation accuracy, of the classical odometry algorithms, such as the ItalianSistema Controllo Marcia Treno(SCMT). The proposed strategy consists of a sensor fusion between the information coming from a tachometer and anInertial Measurements Unit(IMU). The sensor outputs have been simulated through a 3D multibody model of a railway vehicle. The work has provided the development of a custom IMU, designed by ECM S.p.a, in order to meet their industrial and business requirements. The industrial requirements have to be compliant with the European Train Control System (ETCS) standards: the European Rail Traffic Management System (ERTMS), a project developed by the European Union to improve the interoperability among different countries, in particular as regards the train control and command systems, fixes some standard values for the odometric (ODO) performance, in terms of speed and travelled distance estimation. The reliability of the ODO estimation has to be taken into account basing on the allowed speed profiles. The results of the currently used ODO algorithms can be improved, especially in case of degraded adhesion conditions; it has been verified in the simulation environment that the results of the proposed localisation algorithm are always compliant with the ERTMS requirements. The estimation strategy has good performance also under degraded adhesion conditions and could be put on board of high-speed railway vehicles; it represents an accurate and reliable solution. The IMU board is tested via a dedicatedHardware in the Loop(HIL) test rig: it includes an industrial robot able to replicate the motion of the railway vehicle. Through the generated experimental outputs the performances of the innovative localisation algorithm have been evaluated: the HIL test rig permitted to test the proposed algorithm, avoiding expensive (in terms of time and cost) on-track tests, obtaining encouraging results. In fact, the preliminary results show a significant improvement of the position and speed estimation performances compared to those obtained with SCMT algorithms, currently in use on the Italian railway network. [ABSTRACT FROM AUTHOR]

The availability of a reliable speed and travelled distance estimation is relevant for the efficiency and safety of automatic train protection and control systems. This paper investigates the main features of an innovative localization algorithm that integrates tachometers and inertial measurement units. Nowadays, the estimation is performed by an odometry algorithm that relies on wheel angular speed sensors. The objective is to increase the accuracy of the odometric estimation, especially in critical adhesion conditions, through sensor fusion techniques based on Kalman filter theory. The Italian company ECM S.p.A. has supported the project, providing a custom inertial measurement unit based on micro electro-mechanical system sensors for the on-track testing of the algorithm. The preliminary results show a significant improvement of the position and speed estimation performances compared to those obtained with SCMT (Italian acronym for ‘Sistema Controllo Marcia Treno’) algorithms, currently in use on the Italian railway network. A wide set of simulated test results, showing the improvement of the estimation process, is presented and discussed. An accurate train navigation that scarcely relies on information from the infrastructure will open a road map for the development of a more and more effective and efficient exploitation of the railway infrastructure. [ABSTRACT FROM PUBLISHER]

In modern railway Automatic Train Protection and Automatic Train Control systems, odometry is a safety relevant on-board subsystem which estimates the instantaneous speed and the travelled distance of the train; a high reliability of the odometry estimate is fundamental, since an error on the train position may lead to a potentially dangerous overestimation of the distance available for braking. To improve the odometry estimate accuracy, data fusion of different inputs coming from a redundant sensor layout may be used. Simplified two-dimensional models of railway vehicles have been usually used for Hardware in the Loop test rig testing of conventional odometry algorithms and of on-board safety relevant subsystems (like the Wheel Slide Protection braking system) in which the train speed is estimated from the measures of the wheel angular speed. Two-dimensional models are not suitable to develop solutions like the inertial type localisation algorithms (using 3D accelerometers and 3D gyroscopes) and the introduction of Global Positioning System (or similar) or the magnetometer. In order to test these algorithms correctly and increase odometry performances, a three-dimensional multibody model of a railway vehicle has been developed, using Matlab-Simulink™, including an efficient contact model which can simulate degraded adhesion conditions (the development and prototyping of odometry algorithms involve the simulation of realistic environmental conditions). In this paper, the authors show how a 3D railway vehicle model, able to simulate the complex interactions arising between different on-board subsystems, can be useful to evaluate the odometry algorithm and safety relevant to on-board subsystem performances. [ABSTRACT FROM PUBLISHER]

We have previously demonstrated that neuropeptide-EI, at high doses, stimulates the production of cAMP, in caudate putamen, through the activation of adenylate cyclase coupled to specific D1 receptors. The aim of the present work was to find evidences for a probable interaction between this neuropeptide and the dopamine D1 receptor in the mammalian central nervous system. The present data show that neuropeptide-EI, at high concentrations, affected both the maximum binding and the apparent affinity of [n-methyl-3H] (R)-(+)-8 chloro-2,3,4,5- tetrahydro-3-methyl-5-phenyl-1H-3-benzazepin-7-ol hemimaleate to the dopamine D1 receptor in a concentration-dependent manner. [ABSTRACT FROM AUTHOR]

A method is described for generating a precisely phase-controlled linear FM pulse of large time-bandwidth product T·W=N by digitally phase-modulating a square-wave carrier at frequency fo with phase jumps of magnitude π/m, where design parameters N and m are powers of 2. A parabolic function generator, which sequentially computes the square of the number of clock input pulses, furnishes modulation orders and is basically comprised of 2s+1 flip-flops (where 2s=m·N). Frequency of input pulses is m·W, where sweep bandwidth W has to be chosen smaller than 2fo/1+m. Phase quantization noise takes the place of 'linearity' and 'stability' concepts in analog linear FM generators, and its power can be controlled by design parameter m, with a reduction of 6 dB for each doubling of the value of m. Bandpass-filtering of the output-modulated signal gives, in many cases, a satisfactory signal-to-quantization noise ratio, even with m=2. [The system described was developed by the author and H. W. K. Kelly, now of Admiralty Research Laboratory, Teddington, England.] [ABSTRACT FROM AUTHOR]

A transparent circular array in monochromatic plane waves can be regarded as a 'linear spatial filter' in which the contour phase function f(φ-θ), due to a plane wave from direction θ, is the filter impulse response when the plane wave is represented by a delta function δ(φ-θ). The spatial frequency spectrum F(s) [the Fourier transform of f(φ)] is saddleshaped and limited to a bandwidth 2R/lgr;. The angle-spatial bandwidth product is then 4πR/λ, analogously to time-frequency bandwidth product. A spatial processing filter, of impulse response h(φ), can be put in 'series' to synthesize a desired directly function g(φ) at the output, whose spectrum G(s) satisfied the above bandwidth limitation. Function h(φ) is then obtainable as the inverse transform of H(s)=G(s)/F(s). Optimization of H(s) for maximum signal-to-background ratio for a signal source in isotropic monochromatic reverberation [describable at the array input as white (in s) noise] leads to a matched filter with H(s)=F(s)*/|F(s)|2 that whitens the spectrum measured at the contour and gives a processing gain of 4πR/λ. Then g(φ) is a sin x/x function. [ABSTRACT FROM AUTHOR]