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Catherine Theresa Desmarais

International Telemetering Conference Proceedings / October 17-20, 1988 / Riviera Hotel, Las Vegas, Nevada / With the acceptance of Mil-Std-1553B by vehicle and weapons industries a wealth of new information is available for vehicle testing. In the past, selected data was extracted and included in a standard PCM telemetry stream. But only the selected data was made available. In EA6B and in the proposed IRIG Standard, multiple Mil-Std-1553B data busses are combined with identifying control bits in a single PCM telemetry stream. All of the information traveling each bus is available to the ground station. These formats share a number of features. One is that for each Bus the Mil-Std-1553B word appears in the same order in the telemetry stream. Another is that individual data words do not depend on their position in the telemetry stream for identification, but they do depend on the control information associated with the current message to give meaning to the data words. An efficient approach is outlined for identifying, selecting and routing individual measurements, messages, and/or all Mil-Std-1553B bus information to processes and I/O devices in a data flow environment.

International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California / IRIG 106-86 Chapter 8 describes the standard for acquisition of MIL-STD-1553 traffic flow. All incoming words (command, status, or data) are transmitted and fill words are used to maintain continuous data output. If all incoming words are not needed, or if other data such as sampled analog data from transducers are also to be transmitted, then a different approach is warranted. Selected data from the avionics bus can be placed into predefined PCM words, eliminating the transmission of useless data, and optimizing the bandwidth available to a Class I telemetry system. The engineering considerations and constraints for avionics bus data acquisition and analysis will be explored in this paper.

No description available.

Short-term synaptic depression is the phenomena where repeated stimulation leads to a decreased transmission efficacy. In this thesis, the impact of synaptic depression on the responses and dynamics of network models of visual processing is investigated, and the coding implications are examined. I find that synaptic depression can fundamentally change the operation of previously well - understood networks, and explain temporal nonlinearities present in neural responses to multiple stimuli. Furthermore, I show, more generally, how nonlinear interactions can be beneficial with respect to neural coding. I begin chapter 1 with a short introduction. In chapter 2 of this thesis, the behaviour of a ring attractor network is examined when its recurrent connections are subject to short term synaptic depression. I find that, in the presence of a uniform background current, the activity of the network settles to one of three states: a stationary attractor state, a uniform state or a rotating attractor state. I show that the rotation speed can be adjusted over a large range by changing the background current, opening the possibility to use the network as a variable frequency oscillator or pattern generator, and use mathematical analysis to determine an approximate maximum rotation speed. Using simulations, I then extend the network into two - dimensions, and find a rich range of possible behaviours. Processing in the visual cortex can be non - linear: the response to two objects or other visual stimuli presented simultaneously is often less than the sum of the responses to the individual objects. A maximum function has in some cases been proposed to describe these competitive interactions. More recent data has emphasised that such interactions have temporal aspects as well, namely that the response to an initially presented stimulus can suppress the response to a stimulus presented subsequently, especially if the first stimulus is presented at high contrast. Chapter 3 of this thesis will present a simple neuronal network featuring synaptic depression which can account for much of the temporal aspects of this behaviour, whilst remaining consistent with older data and models. Furthermore, it will show how this model leads to several strong predictions regarding the processing of low contrast stimuli sequences, as well suggesting a link between response latency and suppression strength. The response of the model to a structured sequence of input stimuli also appears to anticipate future stimuli, and we predict that the magnitude of this stimulus anticipation will decrease as contrast is decreased. Following on from investigating the temporal aspects of responses to stimuli pairs, in chapter 4 this thesis examines an abstract model of how coding is impacted by non - linear interactions, for both structured and unstructured stimuli spaces. I find that non- linear methods of responding to pairs of stimuli presented simultaneously can have a beneficial effect on coding capacity, with linearly combined responses generally leading to the highest decoding errors rates. This thesis goes on to examine the interplay between this models noise assumptions and the decoding performance, and finds that many of the assumptions made can be weakened without changing, qualitatively, these findings. In chapter 5, this thesis examines layered networks of noisy spiking neurons with recurrent connectivity and featuring depressing synapses. The contrast dependent latency and spike count statistics of the model are analysed and are found to be strongly dependent on the parameters of the noise. The tuning of parameters for models containing noisy IF neurons is discussed, and an information theoretic approach to tuning is outlined which successfully reproduces earlier work in which noise was tuned to linearise the response of a spiking network. The approach is applied to maximise the ability of the network to filter rapid noise transients at low contrast. I finish the thesis with a short concluding chapter.

Syftet med denna studie var att med enkäter undersöka om alkoholintag, obehag vid kondomanvändning, bristande kommunikation och kunskap om kondomer och kondomanvändning är faktorer som spelar in vid kondomanvändning bland studenter vid ett universitet i Sverige. Kondom är idag det enda preventivmedel som skyddar mot könssjukdomar. Fram till dess att andra sätt att minska förekomsten av könssjukdomar finns tillgängliga är det viktigt att öka kondomanvändningen. Alkohol visade sig i denna studie inte ha någon koppling till grad av kondomanvändning, inte heller upplevda obehag vid kondomanvändning visade sig ha något samband med detta. Kunskap och grad av kondomanvändning visade sig i denna studie inte ha någon koppling till varandra. Undersökningen visade däremot på ett samband mellan kommunikation och i vilken utsträckning studenterna använder kondom. Enkätundersökningen visade att större delen av studenterna inte använder kondom vid sexuella kontakter, men en slutsats vi kan dra efter vår undersökning är att singelkillen på campus är den som är bäst på att använda kondom.

<p>Syftet med denna studie var att med enkäter undersöka om alkoholintag, obehag vid kondomanvändning, bristande kommunikation och kunskap om kondomer och kondomanvändning är faktorer som spelar in vid kondomanvändning bland studenter vid ett universitet i Sverige. Kondom är idag det enda preventivmedel som skyddar mot könssjukdomar. Fram till dess att andra sätt att minska förekomsten av könssjukdomar finns tillgängliga är det viktigt att öka kondomanvändningen. Alkohol visade sig i denna studie inte ha någon koppling till grad av kondomanvändning, inte heller upplevda obehag vid kondomanvändning visade sig ha något samband med detta. Kunskap och grad av kondomanvändning visade sig i denna studie inte ha någon koppling till varandra. Undersökningen visade däremot på ett samband mellan kommunikation och i vilken utsträckning studenterna använder kondom. Enkätundersökningen visade att större delen av studenterna inte använder kondom vid sexuella kontakter, men en slutsats vi kan dra efter vår undersökning är att singelkillen på campus är den som är bäst på att använda kondom.</p>

Introduction: Human papillomavirus (HPV) is the sexually transmitted etiologic agent of cervical cancer. While HPV infects both men and women, little is known about HPV infection in men. Specifically, knowledge of the prevalence of type-specific HPV infection and the distribution of these infections by anogenital anatomic site in men is incomplete. Evaluation of factors associated with HPV infection based on complete anogenital sampling and with HPV-16 antibody detection may lead to a better understanding of HPV transmission and prevention.Methods: A total of 493 asymptomatic men ages 18 to 40 years old were recruited in Tucson, Arizona, and Tampa, Florida, from 2003 to 2006. Eligibility requirements included having had sex with a woman within the past year and having no history of genital warts. Testing for HPV from anogenital swabs from six anatomic sites and semen was conducted by PCR and reverse line blot genotyping for 37 HPV types. Serum antibodies for HPV-16 were detected by ELISA. Self-administered demographic, health, and sexual history/behavior questionnaires were collected. HPV prevalence and type distributions by anatomic site were calculated, as was seroprevalence of HPV-16 antibodies. Multivariate logistic regression was used to identify independent risk factors for HPV infection at any anatomic site and for having HPV-16 antibodies.Results: HPV was detected in at least one sample for 303 (65.4%) men, with 29.2% of men having an oncogenic infection and 36.3% having a non-oncogenic infection. Multiple HPV types were detected in 27.2% of men. Factors associated with infection were a greater lifetime number of female sexual partners, currently smoking 10 or more cigarettes per day, lack of condom use, and more sexual partners in the past three months. HPV-16 antibodies were detected in the serum of 63 (12.8%) men, and detection was associated with increasing age and concurrent detection of HPV DNA in perianal or anal canal samples.Discussion: The combination of more complete anogenital sampling and sensitive HPV detection for 37 HPV types resulted in a higher HPV prevalence in asymptomatic men than previously reported. Smoking and condom use were the most important modifiable risk factors for HPV in men. These results have implications for research of HPV transmission.

La presente tesis doctoral abarca el área de los sistemas de medida de la potencia eléctrica basados en la teoría de la potencia eléctrica definida por el IEEE Std. 1459-2000, en sistemas trifásicos a cuatro hilos. Se analizan y se implementa un sistema de medidas digital basado en dicha teoría que permite medir cada uno de los términos propuestos en el IEEE Std 1459-2000 que representan los distintos fenómenos eléctricos eficientes y no eficientes que se pueden dar en este tipo de sistemas. Se realiza un análisis sobre las teorías de la potencia eléctrica más actuales y se analiza en profundidad la teoría de la potencia eléctrica definida en el IEEE Std 1459-2000 para los distintos tipos de sistemas eléctricos. Se aporta en la tesis una nueva descomposición de la potencia de desequilibrio definida en el IEEE Std 1459-2000, dando lugar a unos nuevos términos que cuantifican de forma independiente el desequilibrio provocado por los usuarios (cargas no equilibradas) y el desequilibrio debido a las tensiones de la red eléctrica. Se incluyen además unos nuevos factores de mérito que permiten cuantificar de una forma más eficiente cada uno de estos desequilibrios los cuales pueden ser incluidos en los equipos de medidas basados en dicha teoría para medir o penalizar a los usuarios. Para la implementación del sistema de medidas digital se propone en esta tesis la utilización de un sistema de sincronización capaz de sincronizarse con la componente fundamental y de secuencia positiva de las tensiones de red. El sistema de sincronización está compuesto por: un filtro pasabanda SOGI (Second Order Generalized Integrator), un sistema para la obtención de la secuencia positiva a través del método de la DSC (Delayed Signal Cancellation) y por un SPLL (PLL software). / Alfonso Gil, JC. (2010). Contribución a la mejora de los sistemas de medida basados en el IEEE Std 1459-2000 [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/8345 / Palancia