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<em></em>Svanenmärkning av lamparmaturWaldowsson, Sanna January 2008 (has links)
<p>This degree project has been performed on commission by Örsjöbelysning AB. The task has been to study alighting armature and compare it to the demands of The Swan Ecolabel. The task was also to recommend adjustments to improve the environmental adaption of the product to meet the demands of The Swan Ecolabel. Furthermore the task has been to gather documentation on the elements of the lighting armature. Such documentation is required to obtain The Swan Ecolabel. The Swan Ecolabel's vision is a sustainable society, in which future generations can benefit from the same conditions and opportunities as we ourselves do. Everyone nowadays is very aware of the environment and its importance, this has led to higher expectations on the industry. That is why the use of Ecolabels is getting more and more common. The Swan is one of the most well known brands in Sweden.</p><p>2008: Nr 8 Teknik</p>
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Sarconema eurycerca (Wehr) : the heartworm of swans and the role of Trinoton anserinum (F) as an intermediate hostCohen, Sharon January 1988 (has links)
All filarial nematodes of the family Onchocercidae are parasites of vertebrates and require intermediate insect hosts for completion of their life-cycles. Eighteen genera within this family are known to infect birds but very few of the associated intermediate hosts have been elucidated. Sarconema eurycerca (Wehr) is a filarial nematode of swans and geese. A recent study of S. eurycerca in American Whistling Swans (Cygnus c. columbianus ) has demonstrated that the intermediate insect host is a feather louse, Trinoton anserinum (Fabricius) (Seegar, 1977). The main aim of the present study was to investigate the relationship between S. eurycerca and British swans and to determine whether T. anserinum is the intermediate host of the parasite in this country. A total of 1128 swans (of all species) were examined from sites in Britain, Denmark and Iceland. Infected swans were detected by examining blood samples for larval stages of S. eurycerca (microfilariae) using a new sedimentation technique developed in the study. An overall incidence of 15.0% was recorded with a significantly higher proportion of juvenile swans being infected. The microfilariae of S. eurycerca exhibited a diurnal sub-periodic rhythm within the host, with maximum counts occurring between 11.00 and 19.00 hours in the peripheral blood supply. T. anserinum was found to satisfy all the attributes required of an intermediate insect host. As an obligate ectoparasite, T. anserinum has a close spatial and temporal relationship with the swan. T. anserinum appears to be capable of ingesting microfilarie of S. eurycerca whilst feeding on blood. All developing larval stages of S. eurycerca were found in T. anserinum and the louse was very mobile and capable of transmitting the nematode from one swan to another. Examinations were made of the nematode, its morphology and pathological effects on both heart tissue and blood components of the swan. Significantly higher lymphocyte percentages and lower eosinophil percentages, haematocrit and red blood corpuscle counts were recorded in swans infected with S. eurycerca.
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A dinâmica sedimentar e a caracterização de Zonas de Erosão Acentuada (ZEA) ao longo do arco praial de Massaguaçu, SP / The sediment dynamics and the characterization of erosional Hot Spot (EHS) in Massaguaçu beach, SPRogacheski, Carlos Eduardo 10 November 2010 (has links)
Nas últimas décadas, a praia de Massaguaçu vem sofrendo processos erosivos intensos, cujos segmentos possuem taxas de recuo acentuadas, denominadas Zonas de Erosão Acentuada (ZEAs). Partindo deste problema este trabalho se propôs a entender a dinâmica sedimentar do arco praial de Massaguaçu e das possíveis causas de formação e manutenção das ZEAs. A coleta de dados se baseou no levantamento batimétrico e do clima de ondas, bem como no levantamento sonográfico de varredura lateral e na coleta de amostras de sedimento de superfície da antepraia de Massaguaçu. Para processar os dados se optou pela aplicação da modelagem numérica utilizando o modelo SWAN (propagação de ondas em águas profundas) e o modelo SMC (módulos OLUCA, COPLA e EROS, que trabalham, respectivamente, com propagação de ondas em águas rasas, simulação de correntes e simulação de transporte sedimentar). Para a formulação da discussão foram selecionados os 6 (seis) casos que apresentaram as condições de ondas mais representativas. Tais casos mostraram que a dinâmica sedimentar e os processos costeiros responsáveis pela formação e manutenção das ZEAs são controlados por dois padrões distintos de ondas incidentes. O primeiro padrão está relacionado às ondas vindas de NE - E, que geram correntes longitudinais para o sul. Suas correntes longitudinais e transversais à costa são de baixa intensidade resultando em um transporte sedimentar e em variações da morfologia praial menos intensos, além de formar células de circulação em vórtices. O segundo padrão, por sua vez, está relacionado às ondas oriundas SSE - SE - ESSE, cujas correntes litorâneas longitudinais rumam ao norte. Tais correntes longitudinais e transversais à costa, apresentam uma intensidade maior, portanto o transporte sedimentar e as variações da morfologia ao longo do arco praial são maiores bem como as células de circulação em vórtices. Partindo desses resultados, percebeu-se que as ZEAs em Massaguaçu estão ligadas a um possível aumento na frequência e na intensidade das tempestades ao longo das últimas décadas e até o presente momento, não há mecanismos naturais que revertam esta retração da linha de costa. / Over the past decades in Massaguaçu beach has happening a strong erosion process with segments that have higher retreat rates, commonly termed as Erosional Hot Spots (EHSs). This research aims the understanding of the sedimentary dynamics along the Massaguaçu embayment and also the possible causes of the formation and maintenance of the EHSs. The methodology was separately on two steps. At first we collected bathymetry, wave and side-scan sonar data, and samples of the surface sediments from the shoreface of Massaguaçu beach. Later, to analyze majority data, we chose to use numerical modeling based on the SWAN model (propagation of waves in deep water) and SMC model (modules OLUCA, COPLA and EROS, that work respectively with the propagation of waves in shallow water, the simulation of currents and finally the simulation of sediment transport). After modeling, we were able to select the 6 (six) most representative wave conditions cases. Those results show that the control of the sediment dynamics and the coastal processes responsible for the formation and the maintenance of ZEA are based on the characteristics of the incident waves. On trying to explain that process, it was possible to recognize two distinct patterns. The first pattern observed is associated with the NE - E waves, generating longshore currents to the south. In this case, both the longshore and the crosshore currents are less intense, forming cells circulation in vortex, resulting in minor variations in sediment transport and beach morphology. The second pattern is related with the SSE - SE - ESE waves, generating longshore currents to the north. In this case both the longshore and the crosshore currents are more intense, although still with occurrence of forming cells circulation in vortex, resulting in a larger sediment transport and morphological changes along the beach. Finally, what we have seem was that the ZEAs in Massaguaçu are possibly linked to a potential increment on storms frequency and intensity over the past decades and unfortunately, at present, there is still no mechanism to recover this natural retreat of the coastline.
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A dinâmica sedimentar e a caracterização de Zonas de Erosão Acentuada (ZEA) ao longo do arco praial de Massaguaçu, SP / The sediment dynamics and the characterization of erosional Hot Spot (EHS) in Massaguaçu beach, SPCarlos Eduardo Rogacheski 10 November 2010 (has links)
Nas últimas décadas, a praia de Massaguaçu vem sofrendo processos erosivos intensos, cujos segmentos possuem taxas de recuo acentuadas, denominadas Zonas de Erosão Acentuada (ZEAs). Partindo deste problema este trabalho se propôs a entender a dinâmica sedimentar do arco praial de Massaguaçu e das possíveis causas de formação e manutenção das ZEAs. A coleta de dados se baseou no levantamento batimétrico e do clima de ondas, bem como no levantamento sonográfico de varredura lateral e na coleta de amostras de sedimento de superfície da antepraia de Massaguaçu. Para processar os dados se optou pela aplicação da modelagem numérica utilizando o modelo SWAN (propagação de ondas em águas profundas) e o modelo SMC (módulos OLUCA, COPLA e EROS, que trabalham, respectivamente, com propagação de ondas em águas rasas, simulação de correntes e simulação de transporte sedimentar). Para a formulação da discussão foram selecionados os 6 (seis) casos que apresentaram as condições de ondas mais representativas. Tais casos mostraram que a dinâmica sedimentar e os processos costeiros responsáveis pela formação e manutenção das ZEAs são controlados por dois padrões distintos de ondas incidentes. O primeiro padrão está relacionado às ondas vindas de NE - E, que geram correntes longitudinais para o sul. Suas correntes longitudinais e transversais à costa são de baixa intensidade resultando em um transporte sedimentar e em variações da morfologia praial menos intensos, além de formar células de circulação em vórtices. O segundo padrão, por sua vez, está relacionado às ondas oriundas SSE - SE - ESSE, cujas correntes litorâneas longitudinais rumam ao norte. Tais correntes longitudinais e transversais à costa, apresentam uma intensidade maior, portanto o transporte sedimentar e as variações da morfologia ao longo do arco praial são maiores bem como as células de circulação em vórtices. Partindo desses resultados, percebeu-se que as ZEAs em Massaguaçu estão ligadas a um possível aumento na frequência e na intensidade das tempestades ao longo das últimas décadas e até o presente momento, não há mecanismos naturais que revertam esta retração da linha de costa. / Over the past decades in Massaguaçu beach has happening a strong erosion process with segments that have higher retreat rates, commonly termed as Erosional Hot Spots (EHSs). This research aims the understanding of the sedimentary dynamics along the Massaguaçu embayment and also the possible causes of the formation and maintenance of the EHSs. The methodology was separately on two steps. At first we collected bathymetry, wave and side-scan sonar data, and samples of the surface sediments from the shoreface of Massaguaçu beach. Later, to analyze majority data, we chose to use numerical modeling based on the SWAN model (propagation of waves in deep water) and SMC model (modules OLUCA, COPLA and EROS, that work respectively with the propagation of waves in shallow water, the simulation of currents and finally the simulation of sediment transport). After modeling, we were able to select the 6 (six) most representative wave conditions cases. Those results show that the control of the sediment dynamics and the coastal processes responsible for the formation and the maintenance of ZEA are based on the characteristics of the incident waves. On trying to explain that process, it was possible to recognize two distinct patterns. The first pattern observed is associated with the NE - E waves, generating longshore currents to the south. In this case, both the longshore and the crosshore currents are less intense, forming cells circulation in vortex, resulting in minor variations in sediment transport and beach morphology. The second pattern is related with the SSE - SE - ESE waves, generating longshore currents to the north. In this case both the longshore and the crosshore currents are more intense, although still with occurrence of forming cells circulation in vortex, resulting in a larger sediment transport and morphological changes along the beach. Finally, what we have seem was that the ZEAs in Massaguaçu are possibly linked to a potential increment on storms frequency and intensity over the past decades and unfortunately, at present, there is still no mechanism to recover this natural retreat of the coastline.
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Phytoplankton ecology in the upper Swan River estuary, Western Australia: with special reference to nitrogen uptake and microheterotroph grazingRosser, S.M. Jane Horner January 2004 (has links)
Phytoplankton succession and abundance in estuaries is known to be influenced by the relative strengths of various seasonally changing physical and chemical factors. Previous studies of Swan River Estuary phytoplankton biomass and composition have identified salinity, temperature, rainfall and nutrients as the most important controlling factors. These conclusions are generally based on analysis of data from river length transects and depth integrated day-time sampling. They describe influences ,affecting whole system phytoplankton abundance and succession. Many of the typical seasonal bloom that develop are ephemeral and only extend over relatively small areas. The focus of this study is a single site, Ron Courtney Island, considered typical of the upper estuary region. This region of the estuary was chosen as representative of the section of river most influenced by allochthonous nutrient input. It has been the region of most frequent and intense algal blooms over the past decade. The factors, physical, biological or physiological, that have the greatest influence on controlling phytoplankton biomass under various ambient conditions for this system are determined. While previous studies have recognised the importance of nitrogen to phytoplankton growth in the Swan River Estuary, they have focused on NO;, with only anecdotal reference to the importance of the alternative nitrogen source, NH4+. This is the first study to explore the influence of different nitrogen source fluxes on phytoplankton biomass in the upper Swan River Estuary. The roles of physiological adaptation to, and preferences for, 'new' (NO,), recycled (NH4+) and organic (urea) nitrogen sources in relation to ambient nutrient levels are explored. / Specific uptake rates (v), normalised to chlorophyll a, for NO;, NH4+ and urea were 0.2 ± 0.04 - 1831.1 ± 779.19, 0.5 ± 0.26 - 1731.6 ± 346.67 and 3.0 ± 0.60 - 2241.2 ± 252.56 ng N μg Chla-1 respectively. Urea concentration (14.8 - 117.7 μg urea-N 1-1) remained relatively constant over the 12 month study period. Measured ambient specific uptake rates for urea represent between 27.5% and 40.4% of total N uptake over the annual period February 1998 -January 1999. Seasonal nitrate uptake over the same period constituted only 11.3% (±10.77%, n=12) to 24.4% (± 13.02%, n=12) with the highest percentage during winter, when nitrate levels are elevated. It is suggested that urea provides a nutrient intermediary over the spring - summer period during transition from autotrophic to heterotrophic dominated communities. Grazing ,and nitrogen recycling are intricately connected by simultaneously providing top-down biomass control and bottom-up nutrient supply. Zooplankton (> 44 μm) grazing has been shown to reduce up to 40% of phytoplankton standing stock at times. Microheterotrophs (<300 pm) can reduce phytoplankton biomass production by up to 100% (potential production grazed, 11.1% day' - 99.6 % day-1) over an annual cycle. This correlated to mean seasonal day-time grazing loss of 80.47 ± 3.5 ngN μg Chla-1 in surface waters and 20.17 ± 9.7 ngN μg Chla-1 at depth (4.5m). Night time grazing for surface and bottom depths resulted in similar nitrogen loss rates (13.03 ± 4.84 ngN μg Chla-1). / Uptake rates for nitrate (r2 0.501) and urea (r2 0.512), doing with temperature (r2 0.605) were shown to have the greatest influence on phytoplankton distribution over depth and time. This research emphasises the need for more detailed investigations into the physiology of nutrient uptake and the effects of nutrient fluxes on phytoplankton biomass and distribution. Further research into the roles of organic nitrogen and pico and nanoplankton in this system is recommended.
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The ecology of fish inhabiting the inter-tidal zone of Swan Bay, Victoria, Australia.Jessop, Rosalind Elinor, mikewood@deakin.edu.au January 1988 (has links)
Swan Bay is a shallow marine embayment of Port Phillip Bay, just north of Queenscliff, Victoria. It has been part of the Harold Holt Marine Reserves since 1977 and is a seagrass habitat. This study investigated the species of fish present in the inter-tidal zone of Swan Bay, collected information on their ecology, investigated the importance of Swan Bay compared to Port Phillip Bay as a nursery and/or breeding area and compared these results with those of similar seagrsss habitats.
Field work was carried out monthly over a two year period, from April 1981 to April 1983, using beach seine nets at Swan Bay and Portarlington.
Forty four species of fish were identified from Swan Bay and nineteen from Portarlington. Fish were most abundant during the summer and autumn months when seagrass growth was at a maximum and least abundant during winter due to the absence of seasonal residents and decreased numbers of permanent residents.
Swan Bay was found to be an important nursery ground for two commercially-caught species: the Yellow-eye Mullet and the King George Whiting. Juvenile Yellow-eye Mullet were more numerous in Swan Bay than at Portarlington. Smell juvenile King George Whiting were more abundant at Portarlington than in Swan Bay where older juveniles were more numerous.
The fish fauna of Swan Bay was found to be similar to western Port but the abundance of species varied. Atherinosome microstoma was the dominant species in terms of abundance and biomass. Diet was found to be different from that reported by Robertson (1979) at Western Port due to the different range of prey items.
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Tormentas de oleaje en el Mediterráneo: Física y Predicción.Bolaños Sánchez, Rodolfo 17 November 2004 (has links)
En la zona costera mediterránea se llevan a cabo una gran cantidad de actividades socioeconómicas. En estas áreas los eventos meteorológicos son un factor importante para su manejo y gestión. Esto ha generado la necesidad de mejorar el conocimiento y la predicción de eventos como las tormentas de oleaje. Por ello, se ha planteado como objetivo principal de esta tesis la caracterización y simulación numérica de tormentas de oleaje.La generación del oleaje es el resultado del sistema acoplado océano - atmósfera. Esta interface y los flujos de momentum entre ambas capas ha sido de interés y ha generado una gran cantidad de investigaciones. Un avance importante ha sido el desarrollo de los modelos de tercera generación de oleaje, capaces de predecir espectros de oleaje a partir de campos de viento. Estos modelos que constituyen la base de esta tesis, consideran el aporte de energía por el viento, la disipación e interacciones no lineales entre ondas.Para este trabajo se han utilizado los modelos WAM y SWAN junto con mediciones de oleaje en la costa catalana. Para forzar los modelos se han utilizado campos de vientos de los modelos atmosféricos MASS ARPEGE. Se han utilizado también datos de viento de estaciones meteorológicas costeras.El viento y oleaje en la franja costera catalana están caracterizados principalmente por componentes del este, noroeste y del sur. Para el caso de tormentas con impacto en la costa, las del este son las más intensas, pero las tormentas del Noroeste pueden generar condiciones de riesgo para la navegación.Se han descrito tormentas características de la costa catalana, considerando su dirección, duración, e intensidad. De manera paralela se han analizado mas detalladamente dos eventos particulares que se registraron en Noviembre 2001 y Marzo-Abril 2002. Ambas tormentas presentaron oleaje de componente principal del este y una cantidad importante de espectros bimodales. Esta característica no se había estudiado a detalle con anterioridad y se debe al oleaje swell del este y a la rotación de los vientos en la costa catalana para volverse del noroeste generando localmente un sistema de oleaje en esta dirección. Debido a esto, la anchura espectral se comporto de manera opuesta a la esperada, pero mostró ser un indicador de la complejidad del estado del mar por lo que se propone que sea utilizada en la estimación del coeficiente de arrastre.Se han utilizado los modelos de oleaje en diferentes situaciones: en un dominio idealizado, en los eventos de Noviembre y Marzo - Abril y durante el invierno 2002 -2003. Los resultados muestran diferencias entre modelos en tiempo y espacio. Utilizando el parámetro integrado de Hs el SWAN mostró un mejor comportamiento para la detección de tormentas. Sin embargo el espectro del WAM mostró en la mayoría de los casos aproximarse mas al espectro medido. Una parte de los errores registrados en los modelos durante las tormentas, se debieron a la mala simulación de la bimodalidad la cual a su vez se debe a una mala resolución espacial y temporal tanto de los modelos de viento como de oleaje. La correcta definición espacial de las islas en el mediterráneo mostró ser poco significante para la validación de las predicciones en la zona costera catalana.Finalmente debemos decir que a pesar de que este trabajo ha avanzado en el conocimiento del oleaje en la costa catalana y el comportamiento de los modelos, este solo es el principio y se debe de dar continuidad a este esfuerzo. Una manera (indispensable) es mejorando las observaciones disponibles e incluir medidas espaciales (satélite, por ejemplo) para la mejor descripción y validación de los modelos. / Many socio-economic activities take place on the Mediterranean coast. Meteorological events are an important factor for the proper management and administration of these activities in this area.This has inspired an improvement of knowledge and forecasting of environmental phenomena such as wave storms. Thus, the main objective of this dissertation is the characterisation and numerical simulation of wave storms.The generation of wind waves are the result of the coupled system which connects the air and the ocean. This layer, and its fluxes, have been of great interest and generated a large amount of research. The development of third generation wave models has been an important step. Such models are able to reproduce directional wave spectra from wind fields taking into consideration wind energy input, dissipation and non-linear interactions. These models are the basis of this dissertation.For this work, we have used the WAM and SWAN models, together with the wind and wave measures on the Catalan coast. The forcing winds came from the MASS and ARPEGE atmospheric models.The wind and waves on the Catalan coast are characterised by an east, northwest and south component. For coastal damage, the storms from the east cause the most severe coastal damage while the northwest storm can create risky conditions for navigation.Typical storms on the Catalan coast are described, taking into account the direction, duration, and significant wave height. Additionally, it was studied in detail two severe storms that were measured during November 2001 and March-April 2002. Both storms presented a mean eastern wave component, however, a large amount of bimodal spectra were found. This feature had not been studied before at this area and it is produced due to the wind rotation (to northwest) at the coast because of the orography. This produces a different behaviour of the spectral width than expected, but such a parameter was an indicator of the complexity of the sea state and thus it is proposed to apply it in the drag coefficient estimation.The wave models were applied under different situations: idealised domain, November 2001 and March-April storms and during a winter period. The results show differences between models in time and space. When considering significan wave height, the SWAN model showed a better behaviour for storm detection. However, the spectral shape was better predicted by WAM. Part of the errors were due to the bad simulation of bimodal features, and at the same time, this was produced by the coarse time and spatial resolution of wind and wave models.Finally we have to outline that this work is an advance in the knowledge of waves on the Catalan coast and the behaviour of the models. However, this is only the beginning and an effort should be made for the continuos development and improvement on this topic. A good start is by increasing the wind and wave measurements available including spatial measures, such as satellite, for the better description and model validation.
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Att styra säkerhet med siffror : En essä om (att se) gränserEngström, Diana January 2015 (has links)
Work, especially that in complex, dynamic workplaces, often requires subtle, local judgment with regard to timing of subtasks, relevance, importance, prioritization and so forth. Still, people in Nuclear Industry seem to think safety results from people just following procedures. In the wake of failure it can be tempting to introduce new procedures and an even stricter "rule following culture". None, or at least very little, attention is given to tacit knowledge and individual skills. I am aiming to highlight the inadequacy of putting too much trust in formalization and that reporting and trending of events will contribute to increased learning, an increased nuclear safety and an efficient operational experience. The ability to interpret a situation concrete depends on proven experience in similar situations, analogical thinking and tacit knowledge. In this essay I intend to problematize the introduction and use of so-called Corrective Action Program (CAP) and computerized reporting systems linked to CAP in the Nuclear Industry. What I found out is that the whole industry, from regulators to licensees, seems to be stuck in the idea that the scientific perspective on knowledge is the only "true" perspective. This leads to an exaggerated belief in that technology and formalized work processes and routines will create a safer business. The computerized reporting system will not, as the idea was from the beginning, contribute to increased nuclear safety since the reports is based on the trigger and not the underlying causes and in-depth analysis. Managing safety by numbers (incidents, error counts, safety threats, and safety culture indicators) is very practical but has its limitations. Error counts only uphold an illusion of rationality and control, but may offer neither real insight nor productive routes for progress on safety. The question is why the CAP, error counts and computerized reporting systems have had such a big impact in the nuclear industry? It rests after all, on too weak foundations. The answer is that the scientific perspective on knowledge is the dominating perspective. What people do not understand is that an excessive use of computerized systems and an increased formalization actually will create new risks when people lose their skills and ability to reflect and put more trust in the system than in themselves.
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The behavioural ecology of the whooper swan (Cygnus cygnus cygnus)Brazil, Mark Andrew January 1981 (has links)
The behaviour and ecology of Whooper Swans (Cygnus cygnus) were studied on the wintering grounds in Scotland and the summering grounds in Iceland, with a view to extending our general knowledge of the biology of this little studied species. Comparisons are drawn between feeding behaviour shown in terrestrial, freshwater and marine habitats. In Central Scotland Whooper Swans were found to feed mainly on agricultural land and to actively select stubble fields, where they fed on waste grain, from their arrival in autumn until mid-winter. They then changed to feeding on grass from mid-winter until their departure in the spring. They were found to have adopted an activity pattern similar to that of geese, i. e. they were diurnal and flew each morning and evening between a roost-site and a feeding site. The daily activity cycle of feeding varies between habitats, but the differences are not fully explained by functional requirements. The factors affecting the timing of morning and evening flights are discussed. The length of the feeding day increased with daylength and the level of feeding per hour increased so that more time was spent feeding in the spring than at any time during the winter. Although Whooper Swans were found to compensate to some extent for the shortness of winter days by departing to the roost later relative to sunset, it is suggested that it is in the spring when their energetic requirements are highest; they need to store enough energy for migration and breeding and/or moult. The percentage of birds head-up was found to decline curvi-linearly with increasing flock size while the percentage feeding increased. Since there was no apparent relationship between peck rate and flock size, birds in larger flocks gain from increased food intake. A seasonal change in flock size was noted in Central Scotland with larger flocks occurring more frequently between autumn arrival and mid-winter than from mid-winter to spring departure. Although other factors may be involved as well, it is suggested that the advantages of flocking to Whooper Swans may vary depending on whether the food is patchily distributed (waste grain), or relatively uniformly distributed (grass). Differences in the amount of time allocated to feeding and vigilance were analyzed according to age and breeding status, and seasonal changes are discussed. The breeding success of the Whooper Swan, measured using the percentage of cygnets and the mean brood size, was found to vary greatly from year to year. Measurements of mean brood size in Iceland during summer were found to correspond well with those in Scotland the following winter. A particularly poor breeding season in 1979, a year with a very late spring, was noted both in Iceland and on the wintering grounds in Scotland. Whooper Swans are monogamous and territorial. The female does most of the nest building and all of the incubation, while the male remains on the territory, usually either vigilant or feeding. The range of behaviours exhibited by males and females during the incubation and fledging are described and the time allocated to them is analyzed. Displays between adjacent territory holders are described for the first time. These displays were found to be commoner during the fledging period than during incubation. Females were also observed to take part in defence against intruders and it is suggested that an important role of the Whooper Swan's territory is to provide a safe feeding area for the family after hatching. Behavioural co-operation between mates helped to maintain a high degree of protection for the nest and cygnets. Cygnets maintained closer proximity to each other than to their parents and tended to associate with a single parent; usually the female. As cygnets aged, distances between them and from them to their parents increased and their parents spent more time feeding and less time vigilant. The behaviour of non-breeding birds is also described and it is suggested that non-breeders tend to moult in a separate flock from failed breeders. Moult and migration are also discussed in order to provide as full a picture as possible of the Whooper Swan's
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On the use of computational models for wave climate assessment in support of the wave energy industryHiles, Clayton E. 02 November 2011 (has links)
Effective, economic extraction of ocean wave energy requires an intimate under-
standing of the ocean wave environment. Unfortunately, wave data is typically un-
available in the near-shore (<150m depth) areas where most wave energy conversion
devices will be deployed. This thesis identities, and where necessary develops, ap-
propriate methods and procedures for using near-shore wave modelling software to
provide critical wave climate data to the wave energy industry. The geographic focus
is on the West Coast of Vancouver Island, an area internationally renowned for its
wave energy development potential.
The near-shore computational wave modelling packages SWAN and REF/DIF
were employed to estimate wave conditions near-shore. These models calculate wave
conditions based on the off-shore wave boundary conditions, local bathymetry and
optionally, other physical input parameters. Wave boundary condition were sourced
from theWaveWatchIII off-shore computational wave model operated by the National
Oceanographic and Atmospheric Administration. SWAN has difficulty simulating
diffraction (which can be important close to shore), but is formulated such that it
is applicable over a wide range of spatial scales. REF/DIF contains a more exact
handling of diffraction but is limited by computational expense to areas less than a
few hundred square kilometres. For this reason SWAN and REF/DIF may be used
in a complementary fashion, where SWAN is used at an intermediary between the
global-scale off-shore models and the detailed, small scale computations of REF/DIF.
When operating SWAN at this medium scale a number of other environmental factors
become important.
Using SWAN to model most of Vancouver Island's West Coast (out to the edge of
the continental shelf), the sensitivity of wave estimates to various modelling param-
eters was explored. Computations were made on an unstructured grid which allowed
the grid resolution to vary throughout the domain. A study of grid resolution showed
that a resolution close to that of the source bathymetry was the most appropriate.
Further studies found that wave estimates were very sensitive to the local wind condi-
tions and wave boundary conditions, but not very sensitive to currents or water level
variations. Non-stationary computations were shown to be as accurate and more
computationally efficient than stationary computations. Based on these findings it is
recommended this SWAN model use an unstructured grid, operate in non-stationary
mode and include wind forcing. The results from this model may be used directly to
select promising wave energy development sites, or as boundary conditions to a more
detailed model.
A case study of the wave climate of Hesquiaht Sound, British Columbia, Canada
(a small sub-region of the medium scale SWAN model) was performed using a high
resolution REF/DIF model. REF/DIF was used for this study because presence
of a Hesquiaht Peninsula which has several headlands around which diffraction was
thought to be important. This study estimates the most probable conditions at a
number of near-shore sites on a monthly basis. It was found that throughout the
year the off-shore wave power ranges from 7 to 46kW/m. The near-shore typically
has 69% of the off-shore power and ranges from 5 to 39kW/m. At the near-shore site
located closest to Hot Springs Cove there is on average 13.1kW/m of wave power, a
significant amount likely sufficient for wave power development.
The methods implemented in this thesis may be used by groups or individuals to
assess the wave climate in near-shore regions of the West Coast of Vancouver Island
or other regions of the world where wave energy extraction may be promising. It
is only with detailed knowledge of the wave climate that we can expect commercial
extraction of wave energy to commence. / Graduate
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