935 resultados para Sounding rockets.


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The Delamtect was introduced to the Iowa Department of Transportation through a 1975 Federal Highway Administration demonstration project. The Delamtect is a small mobile unit for conducting a rapid bridge deck survey to determine the extent of delaminations (subsurface fractures). Comparison of the Delamtect with manual sounding methods and drilled cores has demonstrated its reliability. This research has shown the Delamtect to be a more effective, more economical and safer method of surveying bridge decks than manual sounding methods. The Delamtect can also be used to provide a measure of the bond within membrane systems.

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Between late spring and early fall, the development of storms is common in Catalonia. Despite the fact that they usually produce heavy showers of short duration, they can also involve severe weather with ice pellets or hail. While the latter usually affect inland regions, and there are numerous publications on these cases; the analysis of events affecting the coast and causing damage to public and private properties is not so well developed. The aim of this study is to provide additional thermodynamic indicators that help differentiate storms with hail from storms without hail, considering cases that have affected various regions of Catalonia, mainly coastal areas. The aim is to give more information to improve prognosis and the ability to detail information in these situations. The procedure developed involved the study of several episodes of heavy rainfall and hail that hit Catalonia during the 2003-2009 period, mainly in the province of Girona, and validated the proposal during the campaign of late summer and fall of 2009, as well as 2012. For each case, several variables related to temperature, humidity and wind were analyzed at different levels of the atmosphere, while the information provided by the radio sounding in Barcelona was also taken into account. From this study, it can be concluded that the temperature difference between 500 hPa and 850 hPa, the humidity in the lower layers of the atmosphere and the LI index are good indicators for the detection of storms with associated hail.

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Iowa has approximately 1000 bridges that have been overlaid with a nominal 2" of portland cement concrete. A Delamtect survey of a sampling of the older overlaid bridges indicated delaminations in several of them. Eventually these bridges as well as those that have not received an overlay must be programmed for rehabilitation. Prior to rehabilitation the areas which are delaminated must be identified. There are currently two standard methods of determining delaminated areas in bridge decks; sounding with a metal object or a chain drag and sounding with an electro-mechanical sounding system (Delamtect). Sounding with a metal object or chain drag is time consuming and the accuracy is dependent on the ear of the operator and may be affected by traffic noise. The Delamtect requires less field time but the graphical traces require that data reduction be done in the office. A recently developed method of detecting delamination is infrared thermography. This method is based on the temperature difference between sound and delaminated concrete. A contract was negotiated with Donohue and Associates, Inc. of Sheboygan, Wisconsin, to survey 18 p.c. concrete overlaid bridge decks in Iowa using the infrared thermography method of detecting delaminations.

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During the fieldwork in the medieval fortification of Ausa (Gipuzkoa), a vast amount of sherds from several pottery artifacts featured by a cylindrical body has been found out. They presumably had the same function in contexts dated from the first half of xiv century. Although it has not been possible to reconstruct any of these artefacts, the study of the sherds allows us to think that they would have formed some sort of big-sized horn. This high-sounding instrument, which has been frequently reproduced in iconographic references, does not have at this moment any direct parallelism in Hispanic contexts, despite being plentiful of references to similar objects in medieval ranges from Provence and Languedoc. By introducing these artefacts from different approaches, we aim to go over the scarce knowledge of these instruments, whose evidence lets us to believe in their widespread distribution all over the landscape in several material contexts from Medieval Ages.

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During the fieldwork in the medieval fortification of Ausa (Gipuzkoa), a vast amount of sherds from several pottery artifacts featured by a cylindrical body has been found out. They presumably had the same function in contexts dated from the first half of xiv century. Although it has not been possible to reconstruct any of these artefacts, the study of the sherds allows us to think that they would have formed some sort of big-sized horn. This high-sounding instrument, which has been frequently reproduced in iconographic references, does not have at this moment any direct parallelism in Hispanic contexts, despite being plentiful of references to similar objects in medieval ranges from Provence and Languedoc. By introducing these artefacts from different approaches, we aim to go over the scarce knowledge of these instruments, whose evidence lets us to believe in their widespread distribution all over the landscape in several material contexts from Medieval Ages.

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The oceanographic work realized during 10 days in the surroundings of the eruptive island of Trindade, 20º30'36" lat. S - 29º19'26" long. W, had as principal aim the determination of the insular plateau, whose knowledge was very insufficient. Thus were established some oceanographic stations and sounding lines were realized by means of an echobathymeter whose responses were initially verified with mechanical soundings obtaneid by means of a Thomson sounder. The insular plateau is very narrow and exhibits a sudden fall between the 100 and 120 m. depth line at 740 m. - 2950 m. from the coast. Its greatest depth is of 108,30 m. and its mean inclination is of 8,12%. The plateau of the island of Trindade is separated from that of the neighbouring group of Martim Yaz by great depths. The bottoms are rocky near the coast, the blocks having been produced by the rupture of the magmatic mass of the island. Further away from the coast, the size of the rocks gradually diminishes up to the fine sand thickness. In the litoral zone there are abundant tufts of living Lithothamnion with a rich associated flora and fauna, which partly covers the rocks themselves. Further off at sea, the spheres of the dead alga with its commensals are cimented together by sedimentation. The spheres are further broken up and become an integrating part of the sand. The results of the physical and chemical analyses of the sand bottoms are shown in tables 2 and 3. The coast is either of abrupt rocky walls falling down to sea level, or of shores, made of pebbles or of sand. Anyhow, there are frequently Lithothamnion terraces slightly inclinated towards the bottom (chemical analysis table 1).

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Operation Musketeer, a combined joint Anglo-French operation aimed at regaining control of the Suez Canal in 1956, has received much attention from scholars. The most common approach to the crisis has been to examine the political dimension. The political events that led Prime Minister Anthony Eden’s cabinet to decide to use military force against the wishes of their superior American ally and in the face of American economic pressure and a Soviet threat to attack Paris and London with rockets have been analysed thoroughly. This is particularly the case because the ceasefire and eventual withdrawal were an indisputable defeat of British policy in the Middle East. The military operation not only ruined Prime Minister Eden’s career, but it also diminished the prestige of Britain. It was the beginning of the end, some claim. The British Empire would never be the same. As the consequences of using force are generally considered more important than the military operations themselves, very little attention has been paid to the military planning of Operation Musketeer. The difference between the number of publications on Operation Corporate of the Falklands War and Operation Musketeer is striking. Not only has there been little previous research on the military aspects of Musketeer, the conclusions drawn in the existing works have not reached a consensus. Some historians, such as Correlli Barnett, compare Musketeer to the utter failures of the Tudor landings and Gallipoli. Among significant politicians, Winston Churchill, who had retired from the prime ministership only a year before the Suez Crisis, described the operation as “the most ill-conceived and ill-executed imaginable”. Colin McInnes, a well-known author on British defence policy, represents the middle view when he describes the execution as “far from failure”. Finally, some, like Julian Thompson, the Commander of 3 Commando Brigade during the Falklands War, rate the military action itself as being successful. The interpretation of how successful the handling of the Suez Crisis was from the military point of view depends very much on the approach taken and the areas emphasised in the subject. Frequently, military operations are analysed in isolation from other events. The action of a country’s armed forces is separated from the wider context and evaluated without a solid point of comparison. Political consequences are often used as validated criteria, and complicated factors contributing to military performance are ignored. The lack of comprehensive research on the military action has left room for an analysis concentrating on the military side of the crisis.

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Meandering rivers have been perceived to evolve rather similarly around the world independently of the location or size of the river. Despite the many consistent processes and characteristics they have also been noted to show complex and unique sets of fluviomorphological processes in which local factors play important role. These complex interactions of flow and morphology affect notably the development of the river. Comprehensive and fundamental field, flume and theoretically based studies of fluviomorphological processes in meandering rivers have been carried out especially during the latter part of the 20th century. However, as these studies have been carried out with traditional field measurements techniques their spatial and temporal resolution is not competitive to the level achievable today. The hypothesis of this study is that, by exploiting e increased spatial and temporal resolution of the data, achieved by combining conventional field measurements with a range of modern technologies, will provide new insights to the spatial patterns of the flow-sediment interaction in meandering streams, which have perceived to show notable variation in space and time. This thesis shows how the modern technologies can be combined to derive very high spatial and temporal resolution data on fluvio-morphological processes over meander bends. The flow structure over the bends is recorded in situ using acoustic Doppler current profiler (ADCP) and the spatial and temporal resolution of the flow data is enhanced using 2D and 3D CFD over various meander bends. The CFD are also exploited to simulate sediment transport. Multi-temporal terrestrial laser scanning (TLS), mobile laser scanning (MLS) and echo sounding data are used to measure the flow-based changes and formations over meander bends and to build the computational models. The spatial patterns of erosion and deposition over meander bends are analysed relative to the measured and modelled flow field and sediment transport. The results are compared with the classic theories of the processes in meander bends. Mainly, the results of this study follow well the existing theories and results of previous studies. However, some new insights regarding to the spatial and temporal patterns of the flow-sediment interaction in a natural sand-bed meander bend are provided. The results of this study show the advantages of the rapid and detailed measurements techniques and the achieved spatial and temporal resolution provided by CFD, unachievable with field measurements. The thesis also discusses the limitations which remain in the measurement and modelling methods and in understanding of fluvial geomorphology of meander bends. Further, the hydro- and morphodynamic models’ sensitivity to user-defined parameters is tested, and the modelling results are assessed against detailed field measurement. The study is implemented in the meandering sub-Arctic Pulmanki River in Finland. The river is unregulated and sand-bed and major morphological changes occur annually on the meander point bars, which are inundated only during the snow-melt-induced spring floods. The outcome of this study applies to sandbed meandering rivers in regions where normally one significant flood event occurs annually, such as Arctic areas with snow-melt induced spring floods, and where the point bars of the meander bends are inundated only during the flood events.

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Jacob Hindman (1789-1827) was an American military officer who was a captain of the Second U.S. Artillery during the War of 1812. He commanded troops at the battles at Fort George and Stony Creek in 1813, and in June of that year became the major of the Second Artillery. He remained in this position until May of 1814 when the regiment was merged with the Corps of Artillery. During the Niagara campaign in 1814, Hindman’s company commanders included Nathan Towson, Thomas Biddle, John Ritchie, and Alexander Williams. During the British attack on Fort Erie in August 1814, Hindman led an assault for which he later received a brevet promotion to lieutenant colonel for “gallant conduct in the defense of Fort Erie”. In 1815, he received an additional brevet for “meritorious services”. He is generally regarded as one of the most successful artillerists of the War of 1812. James Hall (1793-1868) served with the U.S. military as a second lieutenant in the Second Artillery during the War of 1812. He fought in the Battle of Lundy’s Lane and was General Brown’s messenger during the attack on Fort Erie. He left the military in 1818 and became a newspaper editor and author. His experiences during the War of 1812 provided material for two stories, The Bearer of Despatches and Empty Pockets. Much of his work sought to popularize the West and promote western authors.

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This paper develops a model of short-range ballistic missile defense and uses it to study the performance of Israel’s Iron Dome system. The deterministic base model allows for inaccurate missiles, unsuccessful interceptions, and civil defense. Model enhancements consider the trade-offs in attacking the interception system, the difficulties faced by militants in assembling large salvos, and the effects of imperfect missile classification by the defender. A stochastic model is also developed. Analysis shows that system performance can be highly sensitive to the missile salvo size, and that systems with higher interception rates are more “fragile” when overloaded. The model is calibrated using publically available data about Iron Dome’s use during Operation Pillar of Defense in November 2012. If the systems performed as claimed, they saved Israel an estimated 1778 casualties and $80 million in property damage, and thereby made preemptive strikes on Gaza about 8 times less valuable to Israel. Gaza militants could have inflicted far more damage by grouping their rockets into large salvos, but this may have been difficult given Israel’s suppression efforts. Counter-battery fire by the militants is unlikely to be worthwhile unless they can obtain much more accurate missiles.

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L’étude de « Tous les matins du monde», de Pascal Quignard, et ponctuellement, de « Terrasse à Rome», nous permettra d’examiner les relations entre cinéma et littérature d’un point de vue poétique et esthétique et d’approfondir l’approche intermédiale de la littérature. À l’aide de la théorie de la lecture d’Umberto Eco, nous montrerons comment l’encyclopédie filmique du lecteur peut le rendre réceptif à un effet-cinéma en littérature. Nous étudierons les indices implicites qui, ensemble, permettent de parler d’une esthétique filmique. Trois grands chapitres permettront d’étudier cela : vision, montage et univers sonore du texte. Cet angle d’approche devrait permettre de relire « Tous les matins du monde » suivant une perspective critique nouvelle, tout en approfondissant les recherches sur l’intermédialité.

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Dept.of Marine Geology & Geophysics, Cochin University of Sceince and Technology

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The main purpose of the thesis is to improve the state of knowledge and understanding of the physical structure of the TMCS and its short range prediction. The present study principally addresses the fine structure, dynamics and microphysics of severe convective storms.The structure and dynamics of the Tropical cloud clusters over Indian region is not well understood. The observational cases discussed in the thesis are limited to the temperature and humidity observations. We propose a mesoscale observational network along with all the available Doppler radars and other conventional and non—conventional observations. Simultaneous observations with DWR, VHF and UHF radars of the same cloud system will provide new insight into the dynamics and microphysics of the clouds. More cases have to be studied in detail to obtain climatology of the storm type passing over tropical Indian region. These observational data sets provide wide variety of information to be assimilated to the mesoscale data assimilation system and can be used to force CSRM.The gravity wave generation and stratosphere troposphere exchange (STE) processes associated with convection gained a great deal of attention to modem science and meteorologist. Round the clock observations using VHF and UHF radars along with supplementary data sets like DWR, satellite, GPS/Radiosondes, meteorological rockets and aircrafl observations is needed to explore the role of convection and associated energetics in detail.

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En la Enfermedad Coronaria (EC) existen factores genéticos, socioculturales, medioambientales y raciales adicionales a los factores de riesgo cardiovascular mayores que podrían influir en su presentación. Se desconoce el impacto de la raza en la severidad de la enfermedad coronaria en los pacientes extranjeros que son enviados a nuestro Servicio. Objetivos: Comparar la severidad de la EC multivaso en una población de pacientes de las Antillas y Nacionales, pareados por la escala Framingham. Metodología: Realizamos un estudio de corte transversal, comparando pacientes colombianos contra pacientes provenientes de las Antillas holandesas con similares factores de riesgo según escala de Framingham, catalogándolos por grupos de riesgo bajo, intermedio, alto y muy alto. Todos con EC severa multivaso documentada por angiografía coronaria desde enero del 2009 hasta Junio de 2011. Se excluyeron pacientes con antecedentes de intervención percutánea o quirúrgica previa. Resultados: Ingresaron 115 pacientes internacionales y 115 pacientes nacionales. La relación hombres/mujeres 3:1. La proporción de grupos de riesgo fue de bajo riesgo 2.5%, intermedio 15%, alto 19.3%, y muy alto 63.4%. El Syntax Score en pacientes nacionales fue 14.3+/-7.4 y en internacionales 22.2+/-10.5 p: 0.002. Conclusiones: En pacientes provenientes de las Antillas Holandesas, valorados en nuestra institución, se observó una mayor severidad de la enfermedad coronaria comparada con una población nacional con factores de riesgo similares. Estos hallazgos sugieren la influencia de la raza y factores genéticos en la severidad y extensión de la EC