Thesis (S.M.)--Massachusetts Institute of Technology, 2007. / Title from title screen (viewed Apr. 16, 2008). "June 2007." Includes bibliographical references (p. 137-138). Also issued in paper format.

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The theme of this work is an Allied Arctic convoy PQ 16 and its connection to history within the military, but political and military history of everyday life. For this voyage and its associated naval battle took place at the end of May 1942. In the seven chapters deals with both sailing alone group PQ 16, as well as the Allied naval strategy and tactics applied on the Arctic battlefield of World War II. In the context of interpreting the meaning convoys in terms of material assistance to the Soviet Union, the text includes a broader discussion of research on this issue globally, especially in connection with the frequent ideological load previous research on both sides of the warring blocks. Work is mainly based on unpublished archival sources from the UK, while also dealing with the possibilities of their analysis and interpretation in the context of research nautical history of the Second World War. The conclusion concerning the appraisal výzamu convoy PQ 16 as a major naval victory of the Allies. KEYWORDS World War II, naval war, allied arctic convoys, naval strategy

<p>Kretanje potiskivanog sklopa/sastava je njegova sposobnost da se premešta<br />nekom brzinom usled delovanja određene sile koja mu je pridodata.Ovu silu<br />stvaraju brodski propeleri i pri zadatoj brzini v=const ona treba da bude<br />jednaka sili otpora sredine-vode i vazduha.Iz tog razloga korisna sila koju<br />razvijaju propeleri broda-potiskivača pri plovidbi sa sastavom potisnica<br />pri v=const treba da savlada ne samo otpor svih potisnica u sastavu već i<br />sopstveni otpor broda. Za planere procesa vodnog prevoženja neophodno je,<br />osim poznavanja veličine otpora sredine pri plovidbi potiskivanih<br />sklopova i poznavanje redukovanih i specifičnih otpora pojedinih tipova<br />potiskivanih teretnjaka i sastva koje oni čine. Osim toga, predložene su<br />metode za proračun očekivanih brzina plovidbe u mirnoj vodi i očekivanih<br />vrednosti pokazatelja statičkog opterećenja utvrđenih na osnovu obavljenih<br />eksperimenata po pojedinim tipovima brodova i potiskivanih sastva. Takođe,<br />predloženi su novi tehnički i eksploatacioni pokazatelji za ocenu<br />ispravnosti rada potiskivača, koji do sada nisu primenjivani u Srbiji. Na<br />kraju disertacije prikazane su metode kojima se rešavaju praktični zadaci<br />prevoženja po različitimh brodovima potiskivačima i potiskivanim<br />sastavima.</p> / <p>Movement of convoy/pushed convoy is its ability to change place due to certain<br />force that drives it. This force is created by ship&rsquo;s propellers for given speed v=const<br />and it should be equal to resistance of surrounding water and air. This is the reason<br />why useful force created by ships propellers (thrust) created by propellers of pushboat<br />while navigating with a convoy at v=const needs to overcome not only the<br />resistance of barges but push-boat&rsquo;s resistance as well. For planers of transport<br />process it is necessary to know, besides the resistance of surroundings during<br />navigation of pushed convoys, the value of reduced and specific resistance for certain<br />types of barges and convoys that they form. Apart from that methods for calculation<br />of expected speeds of navigation, value of static load of engines based on<br />experimental research. Besides that new exploitation parameters for determination of<br />push-boat&rsquo;s work are proposed, which haven&rsquo;t been used in Serbia. At the end<br />dissertation presents methods to solve practical transportation tasks for different<br />ships with different convoys.</p>

Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / Nesta dissertação são avaliados os efeitos dinâmicos provenientes da travessia de comboios de veículos sobre o tabuleiro irregular de obras de arte rodoviárias de concreto armado. O modelo matemático empregado para simular o comportamento do sistema veículo-ponte considera a participação da massa e da rigidez das viaturas na definição das freqüências do sistema e, conseqüentemente, a força de interação entre os veículos e a ponte é afetada pela flexibilidade desta. A ponte é modelada a partir do emprego de elementos finitos de barra unidimensionais e discretizado com massas concentradas e flexibilidade distribuída. O modelo de veículo empregado baseia-se no veículo TB-12 preconizado pela norma brasileira NBR 7188. Este veículo é simulado por sistemas de massas, molas e amortecedores sendo descrito por graus de liberdade à translação e rotação no plano. As irregularidades da pista são definidas por um modelo não-determinístico com base na densidade espectral do pavimento. O carregamento sobre a ponte é constituído por sucessões de veículos deslocando-se com velocidade constante sobre a obra. Devido à própria natureza das irregularidades da pista e do comboio de veículos, atenção especial é concentrada na fase permanente da resposta do sistema. São estudadas as respostas de dois modelos estruturais existentes, com base em tabuleiros isostáticos, em concreto armado, com e sem balanços, em seção do tipo T e duplo T, respectivamente, em termos de deslocamentos e esforços nas seções onde ocorrem os efeitos máximos. As conclusões do trabalho versam sobre a influência da velocidade, espaçamento e do número de veículos, referentes a situações distintas de carregamento, no que tange a resposta dinâmica das pontes rodoviárias de concreto armado. A magnitude dos efeitos dinâmicos associados à interação dos veículos com o pavimento irregular também é investigada. / In this investigation the dynamic effects induced by the vehicles crossing on the irregular pavement surfaces of reinforced concrete highway bridge decks were evaluated. The mathematical model considered the participation of the mass and stiffness of the vehicles in the definition of the system natural frequencies. The vehicle-bridge mathematical model includes the interaction between the vehicles and bridge dynamical properties. The bridge deck was modelled using beam finite elements with concentrated masses and distributed stiffness. The vehicle model was based on the Brazilian code NBR 7188 standard vehicle TB-12. This vehicle was simulated as mass-spring-damper system and the degrees of freedom of these cars are defined as in plane vertical translations and rotations. The deck surface roughness was defined by a non-deterministic model based on the spectral density of the pavement. The moving load is formed by an infinite succession of vehicles equally spaced and with constant velocity. Only the steady-state response was considered. The dynamic response of two existing structural models corresponding to reinforced concrete highway bridge decks was investigated in terms of displacements and efforts. The conclusions have shown the influence of the velocity, spacing and number of vehicles on the bridges dynamic response. The magnitude of the response amplification due to the surface irregularities was investigated.

Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / Nesta dissertação são avaliados os efeitos dinâmicos provenientes da travessia de comboios de veículos sobre o tabuleiro irregular de obras de arte rodoviárias de concreto armado. O modelo matemático empregado para simular o comportamento do sistema veículo-ponte considera a participação da massa e da rigidez das viaturas na definição das freqüências do sistema e, conseqüentemente, a força de interação entre os veículos e a ponte é afetada pela flexibilidade desta. A ponte é modelada a partir do emprego de elementos finitos de barra unidimensionais e discretizado com massas concentradas e flexibilidade distribuída. O modelo de veículo empregado baseia-se no veículo TB-12 preconizado pela norma brasileira NBR 7188. Este veículo é simulado por sistemas de massas, molas e amortecedores sendo descrito por graus de liberdade à translação e rotação no plano. As irregularidades da pista são definidas por um modelo não-determinístico com base na densidade espectral do pavimento. O carregamento sobre a ponte é constituído por sucessões de veículos deslocando-se com velocidade constante sobre a obra. Devido à própria natureza das irregularidades da pista e do comboio de veículos, atenção especial é concentrada na fase permanente da resposta do sistema. São estudadas as respostas de dois modelos estruturais existentes, com base em tabuleiros isostáticos, em concreto armado, com e sem balanços, em seção do tipo T e duplo T, respectivamente, em termos de deslocamentos e esforços nas seções onde ocorrem os efeitos máximos. As conclusões do trabalho versam sobre a influência da velocidade, espaçamento e do número de veículos, referentes a situações distintas de carregamento, no que tange a resposta dinâmica das pontes rodoviárias de concreto armado. A magnitude dos efeitos dinâmicos associados à interação dos veículos com o pavimento irregular também é investigada. / In this investigation the dynamic effects induced by the vehicles crossing on the irregular pavement surfaces of reinforced concrete highway bridge decks were evaluated. The mathematical model considered the participation of the mass and stiffness of the vehicles in the definition of the system natural frequencies. The vehicle-bridge mathematical model includes the interaction between the vehicles and bridge dynamical properties. The bridge deck was modelled using beam finite elements with concentrated masses and distributed stiffness. The vehicle model was based on the Brazilian code NBR 7188 standard vehicle TB-12. This vehicle was simulated as mass-spring-damper system and the degrees of freedom of these cars are defined as in plane vertical translations and rotations. The deck surface roughness was defined by a non-deterministic model based on the spectral density of the pavement. The moving load is formed by an infinite succession of vehicles equally spaced and with constant velocity. Only the steady-state response was considered. The dynamic response of two existing structural models corresponding to reinforced concrete highway bridge decks was investigated in terms of displacements and efforts. The conclusions have shown the influence of the velocity, spacing and number of vehicles on the bridges dynamic response. The magnitude of the response amplification due to the surface irregularities was investigated.

Through the U.S. Lend-Lease program, President Franklin D. Roosevelt sought to keep Joseph Stalin's Red Army fighting Adolf Hitler's forces to prevent a separate peace and Nazi Germany's colonization of Soviet territory and strategic resources during the Second World War. Yet after the Red Army's 1943 counterattacks, Roosevelt unnecessarily increased Soviet Lend-Lease aid, oversupplying Stalin's soldiers with more armament than they required for the Soviet Union's defense and enabling their subsequent conquest of East Central Europe and large parts of East Asia. Roosevelt's underestimation of the Red Army's capabilities, his tendency to readily rely on Soviet-influenced advisers, and his unquestioning acceptance of Stalin's implicit threats to forge a separate peace all contributed to his excessive arming of Moscow from 1943 forward. Expanding on the findings of other scholars, this work identifies and explains the impact of the Brest-Litovsk Treaty on Roosevelt's reasoning, the key role of the Arctic convoys in delivering material to the Red Army, and how the unnecessary aid routes through Iran and Alaska resulted in the oversupplying of Stalin's troops. Had Roosevelt not opened these unnecessary routes, the Arctic convoys could have continued to sufficiently supply the Red Army's defensive efforts without empowering it to aggressively spread Communism at gunpoint.

The dissertation analyses the reliefs and paintings on thirty-one different tombs in Western Anatolia erected between 600 and 450 BC, in order to illuminate the ways in which non-Greek elites were identified on their memorials. The tombs from three areas are treated: Phrygia, Hellespontine Phrygia and Lydia, where the primary language groups were Phrygian, Mysian and Lydian. There is little literary evidence for these regions, and what there is tends to focus on political developments. Descriptions of people and society are few, and tend to represent them from an outside perspective, grouping them according to cultural characteristics which differentiate them from Greeks. It is clear, however, that the regions were important, prosperous places, controlled by illustrious grandees and land marked with a relatively high proportion of monumental tombs. Of these monumental tombs, there is a relatively high number decorated with striking and articulate images. There is much to be gained from examining the images on these tombs, as ‘indigenous’ sources for how elite Western Anatolians described themselves. Previous approaches to the tombs and their images have tended to look at them individually or in smaller groups, and to concentrate on the transmission and reception of Persian and Greek culture in the Achaemenid provinces. This dissertation contributes a broader comparative study of the decorated tombs, focussing on the kinds of statuses the images represent and the cultural forms these took. By comparing the various methods of self-representation, it clarifies patterns of identities in Western Anatolia and their relationship to historical circumstances. The dissertation is divided into five chapters. An introduction outlines the scope and sample, the historical background, previous studies of the monuments, the definition of ‘identity’ and the methods of analysis adopted here. Three case study chapters present the regions and the decorated monuments within them. A concluding chapter synthesises three aspects: social identities (roles and spheres of life represented); geographic and chronological patterns; and cultural affiliations and orientations. The dissertation concludes that a tension between Persian identities and local traditions is evident in some of the tomb images, which relates to the political upheavals in Western Anatolia and the Aegean at the time of the Persian Wars.