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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Anatomy of an Iron Age Roundhouse: The Cnip Wheelhouse Excavations, Lewis

Armit, Ian January 2006 (has links)
No / When tidal erosion on Cnip beach uncovered a well-preserved wheelhouse complex, it presented a rare opportunity to shed new light on this architectural phenomenon. This title sets out the results of the excavations, placing them in the wider context of the British and European Iron Age.
222

Aeolian dune development and evolution on a macro-tidal coast with a complex wind regime, Lincolnshire coast, UK

Montreuil, Anne-Lise January 2012 (has links)
Coastal foredunes are natural aeolian bedforms located landward of the backshore and which interact continuously with the beach. Traditionally, coastal dunes have been associated with onshore winds, however they can be found under more complex wind regimes where offshore winds are common such as the UK East coast, Northern Ireland and New Zealand. This research investigates the ways in which foredune-beach interactions occur under a complex wind regime at a range of overlapping temporal and spatial scales and is innovative in that it explicitly links small-scale processes and morphodynamic behaviour to large scale and long-term dynamics. The study area is the north Lincolnshire coast, East England. Detailed observations of airflow at three locations under varying wind regimes revealed considerable spatial variations in wind velocity and direction, however it was possible to determine a general model of how foredune topography deflected and modified airflow and the resultant geomorphological implications (i.e. erosion and deposition). During direct offshore and onshore winds, airflow remained attached and undeflected; and distinct zones of flow deceleration and acceleration could be identified. During oblique winds airflow was deflected to become more parallel to the dune crest. The field sites used are characterized by a seasonal erosion/accretion cycle and a series of increasingly complex models was developed and tested to determine whether it was possible to predict sand volume changes in the foredune-beach system based on a limited number of variables. The model predictions were tested against detailed digital terrain models at a seasonal timescale. The model prediction that best matched the observed (surveyed) sand volume changes included wind speed, direction, grain size, fetch effect controlled by beach inundation and angle of wind approach was accurate to within ±10% for 18 out of 48 tests at the seasonal scale and 6 out of 12 tests over periods of >5 years. A key variable influencing foredune-beach sand volume is the magnitude and frequency of storm surge events and this was not factored in to the model, but may explain the model-observation mismatch over the medium-term on two occasions. Over the past 120 years historical maps and aerial photographs indicate long-term foredune accretion of approximately 2 m year-1 at the three study sites (1891-2010). At this timescale, rates of coastal foredune accretion reflect the low occurrence of severe storm surges and suggest rapid post-storm recovery. The morphological response of the foredune-beach morphology is considered to be a combination of controlling and forcing factors. Process-responses within the system, associated with nearshore interactions and sediment transfer from the littoral drift, are compiled into a multi-scale morphodynamic model. Important to match appropriate dataset to scale of research question or management plan being explored. In the case of management, long-term records of past activity are necessary to predict the future but also to understand natural responses of system to short-term impact such as storm surge.
223

Dinâmica de cúspides praiais e fatores condicionantes: Massaguaçú, SP / Beach cusps dynamics and conditionig factors: Massaguaçú, SP

Santos, Hélio Teruo Hashizume dos 17 September 2015 (has links)
O presente trabalho tem por objetivo relacionar a ação das ondas incidentes no arco praial de Massaguaçú com a presença e o comportamento de feições morfológicas como as cúspides praiais. O conjunto de dados utilizados consiste em uma série de imagens provenientes do sistema Argus. Esse sistema utiliza cinco câmeras de alta resolução resultando em uma cobertura de 180° da zona costeira. A partir destas imagens realizou-se a digitalização das cúspides praiais encontrando-se duas linhas de cúspides, uma na face praial superior (CFS) e a outra na face praial inferior (CFI). Em conjunto com os dados de imagem foi analisado o clima de ondas atuantes durante o período. A presença de feições rítmicas foi alta no arco praial de Massaguaçú, sendo praticamente predominante na face praial superior. O espaçamento médio da CFS foi superior ao espaçamento da CFI e a alternância das condições atuantes foi determinante na redução do espaçamento assim como condições energéticas baixas. O aumento do espaçamento das cúspides ocorreu sob condições energéticas médias à altas e sob condições extremas observou tanto a destruição como o aumento das feições rítmicas. A interação entre o espraiamento e a morfologia existente, modulado pela variação do nível d\'água, foi um dos motores para a formação de cúspides em níveis inferiores enquanto que as condições extremas causaram sua destruição. / This study aims to relate the action of incident waves on Massaguaçú\'s beach with the presence and the behavior of morphological features such as beach cusps. The set of data used consists in a series of images from the Argus system. This system uses five high-resolution cameras resulting in a 180 ° coverage of the coastal zone. From these images, realize the presence of beach cusps lying in two rows on the beach face, one in the upper beach face (CFS) and the other in the lower beach face (CFI). At the same time with the image data the wave regime acting at Massaguaçú\'s beach was analyzed during the period. The presence of rhythmic features was almost constant Massaguaçú\'s beach face, nearly predominant on the upper beach face. The average spacing of CFS was greater than the spacing of the CFI and the interchange in active conditions was crucial in reducing the spacing as well as low energy conditions. The increased spacing of the cusps occurred under medium to high energy conditions and under extreme conditions both as increased and destruction of the rhythmic features were observed. The interaction between the swash motions and the existing morphology, modulated by varying the water level, was important for the formation of cusps at lower levels while the extreme conditions caused its destruction.
224

Dinâmica de cúspides praiais e fatores condicionantes: Massaguaçú, SP / Beach cusps dynamics and conditionig factors: Massaguaçú, SP

Hélio Teruo Hashizume dos Santos 17 September 2015 (has links)
O presente trabalho tem por objetivo relacionar a ação das ondas incidentes no arco praial de Massaguaçú com a presença e o comportamento de feições morfológicas como as cúspides praiais. O conjunto de dados utilizados consiste em uma série de imagens provenientes do sistema Argus. Esse sistema utiliza cinco câmeras de alta resolução resultando em uma cobertura de 180° da zona costeira. A partir destas imagens realizou-se a digitalização das cúspides praiais encontrando-se duas linhas de cúspides, uma na face praial superior (CFS) e a outra na face praial inferior (CFI). Em conjunto com os dados de imagem foi analisado o clima de ondas atuantes durante o período. A presença de feições rítmicas foi alta no arco praial de Massaguaçú, sendo praticamente predominante na face praial superior. O espaçamento médio da CFS foi superior ao espaçamento da CFI e a alternância das condições atuantes foi determinante na redução do espaçamento assim como condições energéticas baixas. O aumento do espaçamento das cúspides ocorreu sob condições energéticas médias à altas e sob condições extremas observou tanto a destruição como o aumento das feições rítmicas. A interação entre o espraiamento e a morfologia existente, modulado pela variação do nível d\'água, foi um dos motores para a formação de cúspides em níveis inferiores enquanto que as condições extremas causaram sua destruição. / This study aims to relate the action of incident waves on Massaguaçú\'s beach with the presence and the behavior of morphological features such as beach cusps. The set of data used consists in a series of images from the Argus system. This system uses five high-resolution cameras resulting in a 180 ° coverage of the coastal zone. From these images, realize the presence of beach cusps lying in two rows on the beach face, one in the upper beach face (CFS) and the other in the lower beach face (CFI). At the same time with the image data the wave regime acting at Massaguaçú\'s beach was analyzed during the period. The presence of rhythmic features was almost constant Massaguaçú\'s beach face, nearly predominant on the upper beach face. The average spacing of CFS was greater than the spacing of the CFI and the interchange in active conditions was crucial in reducing the spacing as well as low energy conditions. The increased spacing of the cusps occurred under medium to high energy conditions and under extreme conditions both as increased and destruction of the rhythmic features were observed. The interaction between the swash motions and the existing morphology, modulated by varying the water level, was important for the formation of cusps at lower levels while the extreme conditions caused its destruction.
225

Longshore currents near Cape Hatteras, NC

Smallegan, Stephanie M. 06 April 2012 (has links)
As part of a beach erosion field experiment conducted at Cape Hatteras, NC in February 2010, this study focuses on quantifying longshore currents, which are the basic mechanism that drives longshore sediment transport. Using video imagery, the longshore currents in view of a video camera are estimated with the Optical Current Meter technique and the nearshore morphology is estimated by analyzing breaking wave patterns in standard deviation images. During a Nor‟easter storm event on February 12 and 13, 2010, the video longshore currents are compared to in situ data and it is found that the currents are most affected by the angle of incidence of incoming waves, increasing in magnitude as the angle becomes more oblique due to a larger component of radiation stress forcing in the longshore direction. The magnitude of the radiation stress forcing, which is at least an order of magnitude larger than the surface wind stress, increases as wave height increases or tide level decreases, which causes more wave breaking to occur. The normalized standard deviation images show wave breaking occurring at an inshore and offshore location, corresponding closely to the locations of an inner and outer bar indicated in survey data. Using two profiles from the survey data, one profile that intersects a trough and one that intersects a terrace, the video currents are also compared to currents simulated in one-dimension using the circulation module, SHORECIRC, and the wave module, REF/DIF-S, as part of the NearCoM system. Although the simulated currents greatly underpredict the video currents when the flow is only driven by radiation stresses, a mean water level difference between the two profiles creates a longshore pressure gradient. Superimposing a pressure gradient forcing term into the longshore momentum balance that assumes an equilibrium state of the flow, the magnitude of the simulated currents are much larger than the magnitude of the video estimated currents. Using analytical solutions of simplified forms of the mass and momentum equations to determine the effects of accelerations on the flow, it is seen that the acceleration term greatly affects the flow due to the relatively large mean water level difference that acts over a relatively short distance. Therefore, the pressure gradient forcing term is modified to include the effects of accelerations. By including the two-dimensional effects of the acceleration in the one-dimensional model through the modified pressure gradient, the quasi two-dimensional model simulated currents are very similar to the video estimated currents, indicating that the currents observed in the video may be pressure gradient driven.
226

An hour or two using naval fiction in the United States history course /

Finch, Edward F. Holsinger, M. Paul, January 1999 (has links)
Thesis (D.A.)--Illinois State University, 1999. / Title from title page screen, viewed July 26, 2006. Dissertation Committee: M. Paul Holsinger (chair), Lawrence W. McBride, John B. Freed, Steven E. Kagle. Includes bibliographical references (leaves 225-239) and abstract. Also available in print.
227

An Engineering, Economic, and Political Approach to Beach Erosion Mitigation and Harbor Development: A Review of the Beach Communities of Camp Ellis, Maine, Wells, Maine, and Cape May, New Jersey

Cervone, Edmund January 2003 (has links) (PDF)
No description available.
228

Analýza procentuálního zastoupení a úspěšnosti různých druhů útočných úderů v beach volejbale. / Analysis of the percentage of success and different types of attacks in beach volleyball.

Novotný, Jiří January 2018 (has links)
Title: Analysis of percentage representation and success of various kinds of offensive hits in beach volleyball The aim of the work: The aim of the thesis is to find out the percentage success and representation of various offensive hits in the FIVB Beach volleyball World Tour series of men and women teams. Method: The research method was the observation of 24 videos during which I wrote down the necessary data in to a specially prepared chart. By observation and wrote down in to the chart has been gained necessary data for evaluation. Results: The results present the success and representaiton of various offensive hits in the men and women categories. They are summarized in text and charts. In addition, the results informed about the proportions of beach volleyball spike hits and beach volleyball technicals hits, or about representation of blocked offensive hits. The results also including comparison of individual performance levels in FIVB World Tour. Keywords: Beach volleyball, FIVB World Tour, offensive hit, hits analysis, gender comparsion
229

Beach Compaction Impact on Nesting Success of Loggerhead (Caretta caretta) Sea Turtles: A Comparison Between a Natural and Renourished Beach in Northern Broward County, Florida

Kleppan, Danielle R. 01 August 2013 (has links)
The beaches of Broward County, Florida are a prevalent nesting site for loggerhead (Caretta caretta) sea turtles, however extensive beach erosion is threatening critical nesting habitat. Beach renourishment, the process of transporting offshore or upland sediment onshore, is a widely used method of replenishing lost sand. However, renourishment can negatively affect sea turtle nesting habitat by increasing beach compaction; the resistance to applied pressure in pounds per square inch (psi). Increased sand compaction impedes the digging of the female which affects nesting success. The influence of beach compaction on sea turtle nesting patterns has never been previously examined over the course of a nesting season on Hillsboro and Deerfield Beach. Therefore, this study was designed to examine beach compaction data for Hillsboro, a mostly natural beach, and Deerfield, a completely renourished beach, during the 2010 nesting season and analyze the compaction data against 2010 nest and false crawl (FC, non-nesting emergence) data. Compaction readings were collected during every other week March-October using a soil compaction meter at every other street address along three beach positions, the dune base, mid-beach, and average high tide line (HTL); and at three depths, 15 cm, 30 cm, and 45 cm. Values were not statistically different throughout the season for each beach, so seasonal mean compaction values were used for each beach position and depth. Hillsboro compaction values were rarely over 500 psi (35 kg/cm2), even at 45 cm depth. Deerfield compaction values exceeded the 600 psi (42kg/cm2) measurement limit of the meter in approximately 60% of the compaction values at 30 cm or 45 cm depth. Sand compaction data was analyzed for any trends between beaches as well as within each beach. Historical data shows higher loggerhead nesting success, the number of nests/total number of crawls (including FC) x 100, on Hillsboro Beach than on Deerfield Beach. The average beach compaction values were compared to nesting success and to nest and FC density within each station area. There was a significant inverse relationship (p<0.05) between beach compaction and nesting success at each of the beach positions and depths, when both Hillsboro and Deerfield Beaches were analyzed together, except at the Mid 30 cm and Dune 45 cm depth. The strongest relationship for the combined beaches was at the HTL 15 cm depth (R2=0.3821, p<0.001). When Hillsboro was analyzed alone, beach compaction and nesting success was only significantly inversely related (R2=0.0875, p<0.02) at the HTL 15 cm depth. This demonstrates that while increased beach compaction may partially influence nesting success, there are likely other beach characteristics that contribute to nest site selection of loggerheads in Northern Broward County. The inverse relationship between Hillsboro mean beach compaction and nest density (nests per meter) was significant only at the HTL 15cm depth (p<0.002) and the inverse relationship between mean beach compaction and false crawl density (FC per meter) in Hillsboro was only significant at the Dune 15 cm (p<0.019) and the Dune 30 cm (p<0.038) depths. Although, increased beach compaction was expected to relate to higher FC density, FC density showed a significant inverse relationship to mean beach compaction at all Deerfield Beach positions and depths in and this suggests off-shore factors may be affecting nest site selection.
230

Determining The Impacts Of Beach Restoration On Loggerhead (caretta Caretta) And Green Turtle (chelonia Mydas) Nesting Patterns And Reproductive Success Along Florida's Atlantic Coast

Hays, Allison Whitney 01 January 2012 (has links)
Artificial beach nourishment, the most common method to mitigate coastal erosion in the United States, is also considered the most ecologically friendly alternative for shoreline stabilization. However, this habitat alteration has the potential to impact nesting marine turtles and developing hatchlings. The first objective of this study was to determine how nourishing beaches with two different design templates affects loggerhead (Caretta caretta) and green turtle (Chelonia mydas) nesting success, the ratio of nests to the total number of nests and non-nesting emergences, and reproductive success, the ratio of hatched and emerged hatchlings to the total number of eggs deposited. Two types of restoration designs exist along the southern Brevard County, FL coastline, which supports some of the highest density loggerhead and green turtle nesting worldwide. Since 2005, approximately 35 kilometers of beach have undergone 1) fullscale restoration (typically called nourishment), where sand was added above and below the mean high tide line (2005, 2010) or 2) dune restoration, where sand was placed on the dune (2005, 2006, 2008, 2009). To quantify the effects of these restoration types, we used a Before-After-ControlImpact-Paired Series (BACIPS) model, which tests for significance between the difference in nesting success rates at the impact (engineered) and control sites (natural beach) before and after restoration ( ). For loggerheads, there was a significant difference in after dune restoration during the years of construction (2005, 2006, 2008, and 2009; p

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