Operator and organizational maintenance manual : receivers, radio R-1041/ARN and R-1041A/ARN.

"13 May 1963."

Field and depot maintenance manual : receivers, radio R-1041/ARN and R-1041A/ARN.

"18 November 1963."

Lives of eminent persons, consisting of Galileo, Kepler, Newton, Mahomet, Wolsey, Sir E. Coke, Lord Somers, Caxton, Blake, Adam Smith, Niebuhr, Sir C. Wren, and Michael Angelo.

The "Life of Sir Isaac Newton" is substantially a translation from that in the "Biographie universelle", by M. Biot. cf. note at head of article.

A printed hemispherical helical antenna for GPS receivers

A self-matched printed hemispherical helical antenna for potential use in global positioning system receivers is introduced. Unlike wired hemispherical helical antennas, its printed form renders it a much more stable and endurable structure and also easier for fabrication. The optimized antenna shows an impedance bandwidth of 6%, a 3-dB axial ratio bandwidth of 6%-7%, a return loss greater than 20 dB, and a gain of about 9 dB at the center frequency. The patterns of the antenna show a larger mainlobe in the upper half space with relatively small backlobes. Both theoretical and experimental results will be presented.

Advanced receivers for next generation wireless communication systems

Despite extensive progress on the theoretical aspects of spectral efficient communication systems, hardware impairments, such as phase noise, are the key bottlenecks in next generation wireless communication systems. The presence of non-ideal oscillators at the transceiver introduces time varying phase noise and degrades the performance of the communication system. Significant research literature focuses on joint synchronization and decoding based on joint posterior distribution, which incorporate both the channel and code graph. These joint synchronization and decoding approaches operate on well designed sum-product algorithms, which involves calculating probabilistic messages iteratively passed between the channel statistical information and decoding information. Channel statistical information, generally entails a high computational complexity because its probabilistic model may involve continuous random variables. The detailed knowledge about the channel statistics for these algorithms make them an inadequate choice for real world applications due to power and computational limitations. In this thesis, novel phase estimation strategies are proposed, in which soft decision-directed iterative receivers for a separate A Posteriori Probability (APP)-based synchronization and decoding are proposed. These algorithms do not require any a priori statistical characterization of the phase noise process. The proposed approach relies on a Maximum A Posteriori (MAP)-based algorithm to perform phase noise estimation and does not depend on the considered modulation/coding scheme as it only exploits the APPs of the transmitted symbols. Different variants of APP-based phase estimation are considered. The proposed algorithm has significantly lower computational complexity with respect to joint synchronization/decoding approaches at the cost of slight performance degradation. With the aim to improve the robustness of the iterative receiver, we derive a new system model for an oversampled (more than one sample per symbol interval) phase noise channel. We extend the separate APP-based synchronization and decoding algorithm to a multi-sample receiver, which exploits the received information from the channel by exchanging the information in an iterative fashion to achieve robust convergence. Two algorithms based on sliding block-wise processing with soft ISI cancellation and detection are proposed, based on the use of reliable information from the channel decoder. Dually polarized systems provide a cost-and spatial-effective solution to increase spectral efficiency and are competitive candidates for next generation wireless communication systems. A novel soft decision-directed iterative receiver, for separate APP-based synchronization and decoding, is proposed. This algorithm relies on an Minimum Mean Square Error (MMSE)-based cancellation of the cross polarization interference (XPI) followed by phase estimation on the polarization of interest. This iterative receiver structure is motivated from Master/Slave Phase Estimation (M/S-PE), where M-PE corresponds to the polarization of interest. The operational principle of a M/S-PE block is to improve the phase tracking performance of both polarization branches: more precisely, the M-PE block tracks the co-polar phase and the S-PE block reduces the residual phase error on the cross-polar branch. Two variants of MMSE-based phase estimation are considered; BW and PLP.

Modeling, Analysis and Performance Comparison of Two Direct Sampling DCSK Receivers under Frequency Nonselective Fading Channels

Two direct sampling correlator-type receivers for differential chaos shift keying (DCSK) communication systems under frequency non-selective fading channels are proposed. These receivers operate based on the same hardware platform with different architectures. In the first scheme, namely sum-delay-sum (SDS) receiver, the sum of all samples in a chip period is correlated with its delayed version. The correlation value obtained in each bit period is then compared with a fixed threshold to decide the binary value of recovered bit at the output. On the other hand, the second scheme, namely delay-sum-sum (DSS) receiver, calculates the correlation value of all samples with its delayed version in a chip period. The sum of correlation values in each bit period is then compared with the threshold to recover the data. The conventional DCSK transmitter, frequency non-selective Rayleigh fading channel, and two proposed receivers are mathematically modelled in discrete-time domain. The authors evaluated the bit error rate performance of the receivers by means of both theoretical analysis and numerical simulation. The performance comparison shows that the two proposed receivers can perform well under the studied channel, where the performances get better when the number of paths increases and the DSS receiver outperforms the SDS one.

Dise?o de un libro de comics para la ense?anza del movimiento uniforme y el movimiento naturalmente acelerado propuesto por Galileo

Se reconoce que el mecanicismo y la rigidez con la cual se est? ense?ando la f?sica en las escuelas, el cual deja un aprendizaje tan solo de f?rmulas y no de relaciones cualitativas. Para esto se considera el dise?o de un c?mic como material que brinda enormes posibilidades para la ense?anza y el aprendizaje de las ciencias y de la f?sica en particular. Se plantea dise?ar una propuesta para la ense?anza del movimiento uniforme y movimiento natural acelerado a trav?s de un comic y para esto se realizara la revisi?n de la tercera jornada del libro ?Dialogo Entre Dos Nuevas Ciencias? en donde se tratan los teoremas y axiomas del movimiento uniforme y el movimiento natural acelerado de una manera cualitativa y dialogada a trav?s de unos interlocutores.

Plan de entrenamiento y capacitación para el nuevo personal: proyecto Galileo de Schlumberger Surenco S.A.

Las empresas en su direccionamiento estratégico requieren de la estructuración de actividades para mantener control y orden sobre las capacitaciones llevadas a cabo al personal que ingresa a la compañía. En base a esto, se identificó que la empresa Schlumberger Surenco SA, dedicada a la prestación de servicios de petróleo y gas, no poseía un esquema claro de entrenamiento donde se presentaran no solo los conocimientos y objetivos del proyecto, sino detalles vitales para su desempeño dentro de las funciones al momento de su ingreso al proyecto de la compañía. De acuerdo a esta necesidad se decidió crear un Plan de Entrenamiento y Capacitación para el nuevo personal que ingresara en el área de compras también llamado Proyecto Galileo, teniendo en cuenta las necesidades de los mismos y la información que es base para iniciar el desarrollo de carrera dentro de la compañía. Para esto, fue necesario que los trabajadores con mayor trayectoria se reunieran y decidieran como sería la forma más óptima de capacitar a los nuevos ingresos de acuerdo a las habilidades y conocimientos de cada uno; se llegó a un consenso y se determinó que las personas capacitadoras se escogerían según su perfil y experiencia. Luego de identificar a las personas idóneas para las capacitaciones y los puntos clave a resaltar en los entrenamientos se procedió con la formulación de las estrategias para presentación del curso de inducción y la viabilidad de las mismas.

O papel da propriocepção no desenvolvimento da força muscular e da flexibilidade

Universidade Estadual de Campinas . Faculdade de Educação Física