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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.
51

Sjöstridskrafter i fredsfrämjande operationer : En teoriprövande studie av Geoffrey Tills teori i Operation Sharp Guard och UNIFIL MTF448

Jönsson, Anna January 2018 (has links)
This research paper examines the advantages of deployment of naval forces in peace support operations. The study has been undertaken because the research on this subject is fairly limited. The research tends to be normative and traditional strategists are often focusing on the effect of naval force in terms of war. None of the writers on the subject dispute the use of naval force moreover, they tend to highlight the advantages of a naval force.   The purpose is to analyse the usefulness of a naval force in peace support operations. This has been achieved by testing Till´s theory of the inherently advantage of a naval force in a study of two cases, Operation Sharp Guard in the Adriatic Sea during the conflict in former Yugoslavia and the Swedish contribution to UNIFIL MTF448 in Lebanon. These two cases were selected in order to ascertain to what extent Till´s theory can explain the effect of naval force. Results of this analyse demonstrate the existence of sound arguments for the use of naval force in peace support operations and the empirics of the two cases are valid evidence for that. Naval force can sometimes even work as an enabler for ground troops and air force. The analysis shows furthermore that flexibility and strategic mobility was the two most distinguishing features of a naval force in both cases.
52

A Historical and Analytical Description of the South Florida Recreational Tournament Fishery for Broadbill Swordfish, Xiphias gladius

Brewer, Elaine J. 01 April 2011 (has links)
Swordfish (Xiphias gladius) are increasingly sought after by recreational anglers around the world. The Florida Straits in particular are an important breeding and nursery area for North Atlantic swordfish, as well as for being historical fishing grounds for both recreational and commercial swordfish fisheries. The recreational fishery for swordfish in southeastern Florida is categorized into two historical periods. The first period started in 1977 and consists of the first tournaments in the area to specifically target swordfish. Despite high initial catches, low catch numbers forced the tournament fishery to close in 1983. During the second period of the fishery (starting in 2000 to today) the tournament fishery for swordfish has reemerged. Data from a total of 98 swordfish tournaments (17 historic, 81 current) have been collected. For comparison, information has been gathered from 72 istiophorid billfish tournaments within the modern (second) period. These data were gathered from tournament directors, websites, and personal communication with participants of the tournaments. The tournaments studied took place on the east coast of Florida from Stuart south to Key West, with a majority being held between Lighthouse Point and Islamorada in the Florida Keys. Although participation correlates to the number of catches, catch per hour (CPH) remains on a slow although not significant decrease over time. The entry fees for these modern period swordfish tournaments range from $200-600, while those for the more exclusive billfish tournaments are tenfold swordfish entry costs. Similarly, awarded prize monies of billfish tournaments are tenfold and significantly larger than prize monies for swordfish tournaments. The average weight of landed swordfish has shifted slightly in both the historic and the modern periods. Despite the oscillation of catch numbers throughout the two time periods, the weight of caught swordfish remained roughly the same. This may be from the minimum length restrictions implemented in the modern time period, a regulation which did not exist during the tournaments of the historic period.
53

Trends in Incidence of Haematological Malignancies in Kenya: 2000-2013

Ogol, Linda Akinyi January 2016 (has links)
Introduction: Haematological malignancies (HMs) are a rare and diverse group of malignancies accounting for 9% of cancers globally. These group of malignancies differ by age, sex, subtypes, morphology and geography. The burden and the patterns of diversity of HMs is poorly understood in low and middle-income countries including Kenya. Aim: To analyse the time trends of incidence of haematological malignancies in Kenya by broad subtypes from 2000–2013 and to compare differences in trends of HMs between Nairobi and Uasin Gishu counties for the period 2007-2013. Methods: A retrospective study including all HMs for all ages and sex diagnosed in the period of 2000-2013. Information used was from two population based cancer registries; Eldoret and Nairobi cancer registry. Crude incidence rates were directly standardized with the world population to obtain the age-standardized rates (ASR). Sex rate ratios (SRR) and incident rate ratios (IRR) were then calculated to compare the number of excess cases between sexes and counties. Ms Excel and STATA13 software were used to conduct a time trend analysis of haematological malignancies by broad subtypes of non-Hodgkin lymphoma (NHL), Hodgkin lymphoma (HL), myeloma and leukaemia. Using the estimated annual percentage change (APC), increase or decrease in trends of HMs was determined. Results: In Kenya, the mean age at diagnosis for all HMs was 32 years. NHL was the most commonly diagnosed HM in Kenya accounting for 43.6% of the cases. The main basis of diagnosis for NHL and HL cases was by cytology while for myeloma and leukaemia was by histology. A male excess was noted in the NHL, myeloma and leukaemia cases with an exemption of a female excess in the HL cases. Trends in incidence of HMs in Kenya increased by 9.8% with the myeloma subtype contributing greatly to the observed increase. By counties, Uasin Gishu county reported a higher number of HM cases per 100000 than Nairobi county (Uasin Gishu-97.6 per 100000 and Nairobi-69.9 per 100000). On the contrary, Nairobi marked a higher increase in trends of HMs than Uasin Gishu county. Conclusion: Trends of haematological malignancies are increasing in Kenya and special attention needs to be given to these under-reported group of malignancies. Finally, this study does support the dire need for a national cancer registry in the country.
54

Hydrologické a hydraulické modelování jako podklad pro plánovací činnost obce – případová studie Lešany u Prostějova

Ulrich, Ondřej January 2019 (has links)
The diploma thesis is focused on the use of software based on an open-source license to determine scale and extent of the flood risk of municipality with the possibility of use for municipality spatial planning activities. The diploma thesis is divided into the theoretical and practical part. Theoretical part deals with issues related to flood wave, flood types, hydrologic and hydraulic modeling, land use documents, land use planning documents and flood control measures of non-technical and technical character with local purpose. In the practical part an analysis of the Lešany u Prostějova territory was carried out for the identification of critical sites from the point of view of the flash floods. The critical sites, also called the critical points, were further analyzed for determination of the scale and extent of the flood risk. At the end of the practical part the used analyses and models for municipal self-government are evaluated. Also, an idealized design of flood control measures and measures for water retention in the landscape are presented. All outputs are presented as maps and included in the annex of the diploma thesis.
55

IO-Link Wireless : Industrial communication protocol

von Hacht, Wilhelm, Solid, Viktor January 2022 (has links)
This thesis investigates two aspects of the protocol IO-Link Wireless (IOL-W), a wireless derivative of the widely established network protocol for industry automation IO-Link (IOL). There is an increasing interest in using wireless solutions within the automation industry. The IOL-W protocol is developed to meet the needs of a wireless protocol that can meet the stringent reliability requirements of industrial applications. The first investigated aspect is whether it is feasible to port existing IOL stacks to IOL-W. The second aspect investigates the possibility to establish IOL-W communication using a generic hardware board supporting Bluetooth Low Energy (BLE) and IEEE 802.15.4, specifically the nRF architecture manufactured by Nordic Semiconductor. The properties and mechanisms of the physical layer of IOL-W are thoroughly researched. Afterward, two open-source IOL stacks are examined as potential candidates for protocol porting. From that examination, the main conclusion is that for a commercial project, it is more feasible to invest in a native IOL-W stack. Porting an IOL stack to IOL-W would be immensely time-consuming since it is not enough only to replace the code responsible for handling the physical layer. One would also need to modify the system management module embedded within every hardware layer. Lastly, the nRF hardware is examined, focusing on its radio capabilities. Several problems arose with the radio configuration and the CRC capability of the nRF boards from the subsequent investigation and experiments; therefore, it is concluded that this particular hardware is inappropriate for implementing IOL-W. / Den här uppsatsen granskar två aspekter av protokollet IO-Link Wireless (IOL-W), en trådlös version av det etablerade protokollet IO-Link (IOL). Det finns ett ökat intresse för trådlösa lösningar i Automationsindustrin och IOL-W protokollet är utvecklat för att bemöta det ökade behovet av pålitlig trådlös industriell kommunikation. Den första aspekten granskar huruvida det är möjligt att konvertera en IOL stack till en IOL-W stack. Den andra aspekten utreder om det är möjligt att etablera IOL-W kommunikation med hårdvara designad för Bluetooth Low Energy (BLE) och IEEE 802.15.4, mer specifikt, nRF arkitekturen tillverkad av Nordic Semiconductor. Egenskaperna och mekanismerna av "physical layer" av IOL-W är grundligt undersökt. Två IOL stackar har granskats och det har undersökts huruvida det med rimlig arbetsinsats går att konvertera någon av dem till IOL-W stackar. Undersökningen kommer att huvudsakligen konstatera att, för ett kommersiellt projekt är det bästa alternativet att investera i en färdig IOL-W stack. Att konvertera en IOL stack till en IOL-W stack är en tidskonsumerande uppgift och kräver grundlig kännedom i både IOL och IOL-W, att ersätta dom nedre lagren av en IOL stack är inte en rekommenderad lösning, eftersom System management modulen kommer att behövas modifieras, då den är inbyggd i varje lager av abstraktions modellen. Till sist, kommer nRF hårdvaran att examineras, fokus kommer att ligga på radions förmåga och kompabilitet. Under projektet gång dök ett flertal problem upp med radio konfigurationen samt CRC förmågan, detta kommer att presenteras med flertalet granskningar och experiment. Slutsatsen av undersökningen blir att nRF hårdvaran inte är lämplig att använda som bas för en implementation av IOL-W.
56

Hydrological Modelling of Al Auja Earth Dam in the Lower Jordan Valley. / Hydrologisk modellering av Al Auja jorddammen i lägre Jordandalen.

Rimfors, Otto, Velichkin, Vadim January 2015 (has links)
In a populated region with very high potential evapotranspiration, where the rainwater falls only during the winter and mostly in the mountains, the need for sustainable water management and fair distribution is crucial. In the West Bank, Palestine, the main potable water source is a karst mountain aquifer system. Precipitation occurs usually in the form of rainfall in the mountainous regions during winter period and recharges the groundwater systems. The water either reaches the surface as spring water, or is extracted through pumped wells. But the scarcity of drinking water in Palestine is not due to lack of water resources or technical knowledge of water extraction but a direct consequence of Israeli policies, water management, breached water rights and the occupation of Palestinian territories. Because of such restrictions, ground water is not an option to provide more freshwater, instead it is suggested to collect rainwater runoff in reservoirs. In 2011, the first surface water dam was built in Palestine in Al Auja, just north of Ariha. It was built as an experimental project for future dams and is therefore a small earth fill dam which will be expanded to collect water also from an adjacent watershed, much larger than the current one. The purpose of this study is to determine how much bigger the reservoir needs to be to safely store the inflowing rainwater runoff in the future. This was achieved through hydrological modelling using the HEC-HMS software which is a physical based model. The data used in this study were: 25 m DEM, land use data, soil data (both from remote sense and field visit), river network map, precipitation data, location of the gauges and geological formations. Field visits and soil tests were also great contributions of insights and knowledge crucial for the project. Hourly time-series data for precipitation for the winters 2011-2012 and 2012-2013 and monthly evapotranspiration for 2010-2011 were used as input to the model. Water level data in Al Uja reservoir with 20 minutes intervals were used to evaluate the simulations. Simulations were first optimized for the current scenario to find sets of parameters that match the changes in water level in the dam reservoir. This was done both for single rainfall events as well as for the whole seasons. The parameters creating the most matching results were used in additional simulations with the adjacent watershed included. The difference in results between the simulations with the current watershed and the expanded one was used to answer how much more water the reservoir would have received during 2011-2012 and 2012-2013 if the larger watershed were included. The model results reveal that the reservoir should have been able to hold about three times as much water as today. Installation of an inflow meter is suggested for the future along with an evaluation of local climate change in precipitation and evapotranspiration.
57

Simulation of the upper Waimakariri River catchment by observed rain & radar reflectivity

Lu, Xiao Feng January 2009 (has links)
ModClark and Clark’s Unit Hydrograph (Clark’s UH) within HEC-HMS software are distributed and lumped models, respectively. Clark’s UH simulates the transformation and attenuation of excess precipitation, and requires time of concentration (Tc) and Storage Coefficient (R) parameters. ModClark transformation accounts for variations in travel time to catchment outlet from all regions of a catchment, and it additionally requires gridded representation of a catchment and Gridded cell-based input files. Four cases (three from observed rain, and one from radar reflectivity) of three chosen events were specifically chosen and examined for the comparison of simulation results with the same estimated initial parameters apart from different rainfall inputs. The Upper Waimakariri River Catchment was divided into ten subcatchments, and the HEC-HMS basin model parameters were estimated by using the physical/hydrological characteristics. However, ModClark transformation was unavailable because of an output error from converting ASCII to gridded Soil Conservation Service Curve Number (SCS CN) format by the conversion tool – ai2dssgrid.exe. Therefore, Mean Aerial Precipitation (MAP) for each subcatchment was calculated by Thiessen polygon method combined with an overlay analysis for grid-cell-based rainfall estimation from radar with geographic information system (GIS) tools. The automated calibration/optimisation procedure included in HEC-HMS package was applied to the cases which showed a deviation between simulation and observed flows. The purpose is to ‘optimise’ the initial estimates of parameters only in a mathematical-fit manner based on the observed flows from the only discharge gauge at Old Highway Bridge (OHB). The TC values calculated from the five equations vary in a relatively narrow range apart from the one from Bransby-Williams equation. Therefore, the values from all the other four equations were averaged and used as the initial TC input. The simulation results showed that there was a notable difference between observed and simulated hydrographs for some case studies even though TC, R, CN, and lag time were calibrated/optimised separately. Also, radar estimated rainfall and grid-based data storage system (DSS) need more investigations.
58

Science at sea : voyages of exploration and the making of marine knowledge, 1837-1843

Millar, Sarah Louise January 2017 (has links)
This thesis is about the historical geography of scientific knowledge production at sea. It focuses on three expeditions of exploration and discovery undertaken, respectively, by France, the United States of America, and Britain, that in the late 1830s sailed into the southern oceans. These voyages marked the last such expeditions to travel by sail alone and came before an acknowledged period of specialized interest in investigating the oceans and the marine environment, exemplified by the sailing of HMS Challenger in 1872. The expeditions share a commonality of period and of destination: their study together provides a hitherto overlooked opportunity to analyse practices of experimentation on, and investigation of, the natural history and physical properties of the marine environment that were integral to the construction of scientific knowledge about the oceans at that time. By attention to archival records, personal correspondence, diaries, published travel narratives and representations of marine phenomena in the form of illustrations, sketches, preserved specimens and displays of numerical material, this thesis examines quotidian shipboard practices to show how the production of scientific ‘facts’ was a matter of constant negotiation between people, weather, instruments and vessels – that occurred as a by-product of the running of the ship as well as of more defined programmes of study by civilian naturalists and naval staff. Informed by work in the history of science, Science and Technology Studies (STS) and Actor-Network Theory (ANT), this thesis highlights how attending to practice in the ambiguous, heterotopic space that was the expedition vessel can reveal the origins of a new, specialized, discipline: what I call here a proto-oceanography. This covers those scientific practices undertaken primarily at sea and from the ship: depth measurement, sea temperature and chemistry, the height of waves, collection of marine specimens and coastal topography, but not those primarily land-based activities such as astronomy, meteorology and terrestrial magnetism. By focusing on work carried out on board ship rather than on land, this thesis offers new insights into the practices of marine investigation and experimentation and the complexities of interrogating a space which was visualised primarily through instruments. This thesis examines how at-sea cultures of collection, measurement and representation can inform geographically nuanced analyses of the production of scientific knowledge.
59

Vliv prostorového rozložení sněhu na průběh povodní / Influence of spatial snow distribution on flood course

Kučerová, Dana January 2010 (has links)
For the purpose of hydrological forecasting on mountains' and sub-mountains' rivers is important knowledge of distribution of snow water equivalent in the watershed. Submitted thesis therefore deals with comparison of 9 interpolation methods in terms of quality of their forecasting when predicting snow depth and snow water equivalent in watershed Bystřice (127,6 km2 ), which is situated in the northwest of Bohemia in the Ore mountains. Point data of snow depth and snow water equivalent used in interpolation were sampled during an off- road measuring in 17. 2. 2010 at the 14 snow sampling locations. The interpolation methods were: (1) Thiessen's polygons, (2) inverse distance weighting, (3) global polynomial (4) local polynomial (5) radial basis functions, (6) ordinary kriging, (7) cokriging, (8) residual kriging and (9) orographic interpolation. Independent variable-altitude used in the calculation of snow depth and snow water equivalent was used only in the last three listed methods. Predictive ability of interpolation methods was evaluated by using cross-validation and visual comparison of predicted maps. The best prediction ability was provided by residual kriging and orographic interpolation. The geostatistical methods were next in the order. The method of Thiessen's polygons and inverse distance...
60

Vliv sněhové pokrývky na odtok vody z povodí v zalesněném a nezalesněném prostředí / Influence of snow cover on catchment outflow in wooded and unwooded environment

Hintnaus, Ivo January 2011 (has links)
This work deals with the evaluation of snow cover and snow spatial distribution in experimental Zbytinský and Tetřivči stream basin. Snow mesaurements were focused on snow depth and a snow water equivalent. Interpolation metods and detailed monitoring of rainfall-flow process were applied in the period of the winter half-year 2009 - 2011. The effects of geografic factors on spatial distribution of snow cover in the accumulation period and in the snow melting period were analysed. The analysis of physical geografic factors effect was focused on vegetation, exposure, slope, wind flow and shading. Results confirmed the strong effect of vegetation in the accumulation and snow melting period. Other physical geografic effects on spatial distribution of snow cover were not so significant. The model HEC-HMS was applied to determine the runoff in both stream basins. Simulations result in the winter half-year period reached good agreement between observed and simulated hydrographs. Effects of snow cover contribution to runoff in the snow melting period in wooded Tetřívčí stream basin and also in antropogenic Zbytinský stream basin were proved based on simulations of outflow and snow water equivalent. Key words: snow depth, snow water equivalent, HEC-HMS, Blanice River basin, Zbytinský stream, Tetřívčí stream

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