To gain insight into four highly ionized high-velocity clouds (HVCs) discovered by Sembach et al., we have analyzed data from the Hubble Space Telescope (HST) and Far Ultraviolet Spectroscopic Explorer (FUSE) for the PKS 2155-304 and Mrk 509 sight lines. We measure strong absorption in O VI and column densities of multiple ionization stages of silicon (Si II, III, and IV) and carbon (C II, III, and IV). We interpret this ionization pattern as a multiphase medium that contains both collisionally ionized and photoionized gas. Toward PKS 2155-304, for HVCs at -140 and -270 km s-1, respectively, we measure logN(O VI) = 13.80 ± 0.03 and logN(O VI) = 13.56 ± 0.06; from Lyman series absorption, we find logN(H I) = 16.37 -0.14+0.22 and 15.23-0.22+0.38. The presence of high-velocity O VI spread over a broad (100 km s-1) profile, together with large amounts of low-ionization species, is difficult to reconcile with the low densities, ne ≈ 5 × 10-6 cm-3, in the collisional/photoionization models of Nicastro et al., although the HVCs show a similar relation in N(Si IV)/N(C IV) versus N(C II)/N(C IV) to that of high-z intergalactic clouds. Our results suggest that the high-velocity O VI in these absorbers does not necessarily trace the warm-hot intergalactic medium but instead may trace HVCs with low total hydrogen column density. We propose that the broad high-velocity O VI absorption arises from shock ionization, at bow shock interfaces produced from infalling clumps of gas with velocity shear. The similar ratios of high ions for HVC Complex C and these highly ionized HVCs suggest a common production mechanism in the Galactic halo.

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper presents an analysis of various methods to address the reproduction of recorded Chapter 10 data in real-time. The standard IRIG 106 Chapter 10 recording format is quickly becoming the most commonly used data recording format in the community. As such, a lot of emphasis has been put on recording requirements including time-stamping, data multiplexing, etc. However, there are additional needs that must be considered when using Chapter 10 as the only permanent data record. It is often necessary to reproduce the original data stream exactly as it was recorded with all its timing characteristics. This paper presents various tradeoffs discovered while designing a real-time playback system for recorded chapter 10 data files. In particular, techniques such as just-enough buffering, data re-ordering, pre-processing, etc will be discussed.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Sensor technology is continually advancing to meet demands of a wide range of potential applications. Many of these applications could be better served by distributed sensing than by traditional centralized sensing. To support these emerging applications, it is important to design and develop a unified framework for communication and network infrastructure capable of supporting various sensing functions. A research prototype operating in the 915 MHz Industrial, Scientific, and Medical band (ISM band) has been developed as potentially the core component of this infrastructure. In this paper, we will present the design and optimization of the system, data processing procedures, system parameters, network protocols, and experimental results.

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Early quiescent galaxies at z similar to 2 are known to be remarkably compact compared to their nearby counterparts. Possible progenitors of these systems include galaxies that are structurally similar, but are still rapidly forming stars. Here, we present Karl G. Jansky Very Large Array (VLA) observations of the CO(1-0) line toward three such compact, star-forming galaxies (SFGs) at z similar to 2.3, significantly detecting one. The VLA observations indicate baryonic gas fractions. greater than or similar to 5 times lower and gas depletion timescales. greater than or similar to 10 times shorter than normal, extended massive SFGs at these redshifts. At their current star formation rates, all three objects will deplete their gas reservoirs within 100 Myr. These objects are among the most gas-poor objects observed at z > 2, and are outliers from standard gas scaling relations, a result that remains true regardless of assumptions about the CO-H-2 conversion factor. Our observations are consistent with the idea that compact, SFGs are in a rapid state of transition to quiescence in tandem with the buildup of the z similar to 2 quenched population. In the detected compact galaxy, we see no evidence of rotation or that the CO-emitting gas is spatially extended relative to the stellar light. This casts doubt on recent suggestions that the gas in these compact galaxies is rotating and significantly extended compared to the stars. Instead, we suggest that, at least for this object, the gas is centrally concentrated, and only traces a small fraction of the total galaxy dynamical mass.

Este trabalho apresenta o estudo de algumas moléculas do meio interestelar úteis para o levantamento do conteúdo de matéria orgânica do universo e para as condições pré-bióticas na Terra e em outros ambientes no universo. Utilizamos como objeto-teste a Nebulosa Cabeça de Cavalo, devido à sua geometria simples, à sua distância moderada até nós, ao seu campo de radiação ultravioleta bem conhecido resultante da iluminação por uma estrela próxima, $\\sigma$ Orionis, e por ter sido extensivamente estudada por diversos trabalhos. Desse modo, podemos investigar com segurança diversos processos físicos e químicos no meio interestelar. O principal instrumento utilizado neste trabalho foi o código PDR Meudon devido ao fato de que é amplamente utilizado por ser um dos programas de análise de dados de projetos recentes de astronomia, como o projeto Herschel, e por ser público. O código pode ser utilizado para modelizar com confiabilidade a Nebulosa Cabeça de Cavalo, visto que ela mesma é uma PDR (região de fotodissociação) prototípica. Atualizamos o setor de química do código para testar diversos cenários de formação de moléculas. Consideramos o impacto nas abundâncias derivadas das moléculas de várias suposições em relação ao estado do gás (modelos isocórico, isotérmico e isobárico), decidindo em favor de um modelo isobárico. Verificou-se o papel dos raios cósmicos e de vários conjuntos de dados das reações químicas. Obtivemos as abundâncias de várias moléculas, incluindo algumas de potencial importância pré-biótica: CN e seus íons, HCN, HNC, nitrilas e seus íons, hidretos de nitrogênio, benzeno. Investigamos o papel dos ânions e dos PAHs. Finalmente, exploramos canais de produção para heterocíclicos nitrogenados com relevância em astrobiologia: pirrol e piridina. As presentes simulações apresentaram como a exploração de uma pequena gama de possíveis canais de produção de heterocíclicos já resultou em abundâncias significativas para ao menos uma espécie de heterocíclicos nitrogenados, a piridina. Dessa forma, excursões sistemáticas pelos diversos canais de produção deverão revelar mais espécies para serem alvos de buscas. / This work presents the study of some molecules of the interstellar medium that are useful for the bookkeeping of the molecular content of the universe and for prebiotic conditions on Earth and in other environments in the universe. The Horsehead Nebula was chosen as test object, due to its simple geometry, its moderate distance to us, its well-known ultraviolet radiation field resulting from the star $\\sigma$ Orionis, and due the fact that it has been extensively studied in several works. In this way, we can safely investigate several physical and chemical processes on the interstellar medium. The main tool used in the present work was the Meudon PDR code due the fact that it is widely used as one of the legacy data analysis programs of current astronomy projects, e.g. the Herschel project, and it is public. The code can reliably model the Horsehead Nebula, since this nebula is a prototypic PDR (photodissociation region). We updated the chemical sector of the code in order to test several scenarios for molecule production. We considered the impact on the derived molecule abundances of several assumptions relative to the gas state (isochoric, isothermal and isobaric models), and the isobaric model was found to be the most plausible. We checked the role of cosmic rays and several datasets of chemical reactions. We derived the abundances of several molecules, including some of potential prebiotic importance: CN and their ions, HCN, HNC, nitriles and their ions, nitrogen hydrides, and benzene. We investigated the role of anions and PAHs. Finally, we explored production channels for astrobiologically relevant nitrogenated heterocycles: pyrrole and pyridine. This presents simulations show us how the exploration of a small quantities of possibles path of prodution of heterocycles resulted already in significants abundances at least one n-heterocycle specie, the pyridine. Thereby, systemact tours for the many productions paths should show more species to be targe of searches.

<p>This report is the written part of a bachelorthesis on the computer engineering program at</p><p>University of Halmstad. The project was a cooperate project that where done together with</p><p>Free2move Holding AB. Free2move is a company with eight employees in Sweden and four in</p><p>Malaysia. The company is today developing Bluetooth modules and RFID chips. The market for</p><p>this kind of products is growing very rapidly, last year it grew 71 percent. The most important</p><p>market for Free2move is to provide other developers with Bluetooth modules.</p><p>Free2move has recieved some inquiries from previous customers about a system that would allow</p><p>communication between two or more persons. After recieving this, Free2move started to evaluate</p><p>the grounds for such a protocol and also how the transmisison time slots should be distributed</p><p>among the parties. The result was planned to manage an infinite number of users and the possibility</p><p>for two users to talk simultaneously.</p><p>The goal of the project was to develop a prototype of a reciever with functionality according to a</p><p>specification and protocol developed by Free2move. One part of the project where to do a research</p><p>of the market to find suitable hardware for the reciever, at least a tranciever/reciever and a processor</p><p>with DA-converter. Factors such as pricing, power cousumption and size should be take in</p><p>consideration during the researchphase.</p><p>Free2move had explicity said that they where intrested in a microprocessor from Texas that had low</p><p>power comsumption and that we should concider takingthat one. The PIC microprocessor from</p><p>Micrichip was one of the other candidates. Since the specification of the protocol demanded a DAconverter</p><p>with 16 bit resouliton an external codec was neccesary to be implemented in to the</p><p>construction.</p><p>During the project negotiations about the structure and functionality of the protocol where still not</p><p>finished. This resulted in a turn in what the goal of this project was, and a new goal where set. The</p><p>goal where now to develop and construct a reciever and a transmitter and make a research of how</p><p>well diffrent kind of protocol would perform.</p>

The Bok globule B335 is a small molecular cloud in the solar neighbourhood near the galactic plane. The aim for this three-paper-study is to construct and analyze the extinction for this globule. The method we apply is to use the light from field stars behind the cloud in broadband filters ranging from UV to the mid-infrared. We have observations performed at the ESO telescopes at La Silla and Paranal as well as at the Nordic 2.5 m telescope at La Palma. Together with images and spectra from 2MASS-, ISO- and Spitzer-archives we are able to cover the wavelength range from 0.35 to 24 μm. An important tool to analyze these observations results in order to get the extinction is the grid of synthetic stellar atmospheric spectra provided by Hauschildt (2005). The extinction so received is a result in itself. From the analysis of the extinction wavelength dependence we derive properties of the dust, especially its composition and grain size distribution. By modeling the grain size distribution we are able to find the extinction from the reddening of the stars. We find that the extinction in the optical wavelength 0.35 to 2 μm range nicely follows the functional form described by Cardelli et al. (1989). Our result from the wavelength range redward of 2 μm show an extinction dependent on the part of the cloud examined. For the rim of the cloud we get an extinction similar to that reported earlier for the diffuse interstellar medium. From the central parts of the cloud, however, a higher extinction was found. Our grain size model contains a carbonaceous particle distribution and a silicate one. The result can be explained by depletion of carbon onto carbonaceous grains and also by carbon onto all grains including the silicates. Our modeling of the extinction and our classification of the background stars allow us to - determine the distance to the globule - estimate the gas column density ratio - estimate the mass of globule - get a handle on the dust conversion processes through the grain size distribution   From the water- and CO-ice spectra we are able to estimate the ice column densities. We find similar ice column densities for the two ices. The estimates differ, when calculated from band strengths or from Lorenz-Mie calculations of ice mantles on the grain size distribution, by a factor of two.

Den här undersökningen handlar om säkerhetsorganisationen ombord på fartygen hos Östersjöns tre största operatörer inom kryssningsbranschen. Syftet med undersökningen var att studera tre fartygs säkerhetsorganisationer och hur dessa verkar vid en nödsitation. Fokus låg på att undersöka vilka vitala funktioner som en säkerhetsorganisation är beroende av och hur säkerhetsorganisationen agerar om en eller flera vitala funktioner skulle falla bort. Den metod som användes var en kvalitativ undersökningsmetod i form av djupintervjuer med sju respondenter. Denna metod valdes för att ge respondenterna stor plats för att förmedla egna tankar och personliga erfarenheter. Resultatet visade att de vitala funktionerna en säkerhetsorganisation framför allt är beroende av är ledningsgruppen, maskingruppen och brandgrupperna. Säkerhetsorganisationerna säkerställer bortfall av de vitala funktionerna genom ett vice-system. De har även i ett förebyggande syfte valt att applicera en flexibilitet inom säkerhetsorganisationen som möjliggör omorganiseringar vid bortfall i en nödsituation.