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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.
491

Návrh vakového jezu v Oslavanech / Design of Inflatable Weir in Oslavany

Kocman, Tomáš January 2013 (has links)
This thesis describes the current state of the river Oslava in Oslavany design and reconstruction of the existing fixed weir in the affected location. As a best alternative reconstruction of the existing fixed weir reconstruction was chosen the hard threshold floating weir inflatable weirs. The next part of the thesis describes the proposed solution, and the last part of the thesis deals with the assessment of the proposed solutions.
492

Druhá etapa přeložky I/9 Dubice – Dolní Libchava / The second phase shifting I/9 Dubice - Dolni Libchava

Belda, Miroslav January 2013 (has links)
Master's thesis will deal with the second phase of shifting I/9 Dubice - Dolni Libchava passing west of the Ceska Lipa with an approximate length of 3 km stretch. Estimated start-up of this section is in 2014. This project should build on in the future by-pass Ceska Lipa and Novy Bor, which is currently without funds for implementation by 2025. Traffic load after completion of the by-pass should be approximately 16500 vehicles / 24 hours in 2030. The section is designed in the category S 9.5 with optional solving two major intersections. This thesis will focus on reducing the cost of construction of the section.
493

Three essays in applied economics with panel data / Trois essais d'économie appliquée sur données de panel

Darpeix, Pierre-Emmanuel 01 October 2018 (has links)
Cette thèse se compose de trois articles empiriques appliquant à divers sujets des techniques d'économétrie sur données de panel. L'article principal étudie l'évolution de la transmission des prix des trois principales céréales (blé, maïs, riz) des marchés internationaux vers les producteurs domestiques pour 52 pays sur la période 1970-2013, et cherche à identifier les principaux facteurs expliquant l'hétérogénéité des pass-through. Le second article mesure l'élasticité du trafic aérien au produit intérieur brut dans le monde et met en évidence la grande stabilité de la relation tant dans le temps que d'une région à l'autre. Enfin, le troisième article modélise le mécanisme de fixation du taux de rendement servi par les assureurs français à leurs clients sur les produits d'assurance-vie. / This dissertation is composed of three empirical articles resorting to econometric methods in panel data analysis to address various research questions. The main article investigates the evolution of the level of price transmission for the three major cereals (wheat, maize and rice) from the international commodity markets down to the local producers for 52 countries between 1970 and 2013 while attempting to identify the main drivers of the heterogeneity in pass-through. The second article measures the elasticity of air-traffic to GDP around the world and demonstrates that the relationship is very stable across régions and through time. Eventually, the third article models the mechanisms through which French life-insurers set the rate of return they pay annually to their policyholders.
494

Determinants of investment activities : a comparative analysis of the BRICS and some selected SADC countries

Letsoalo, Lourence. January 2021 (has links)
Thesis (M. Com. (Economics)) -- University of Limpopo, 2021 / Investment as one of the main macroeconomic variables can ensure development of infrastructure and economic growth through increasing productivity and attracting investors. This study examined key determinants of investment activities by means of a comparative analysis between the SADC and BRICS groups during the period 2004- 2019. The key variables were the real exchange rate, real interest rate and trade openness. The analysis began by reporting unit roots tests, which paved way for employing Panel Autoregressive Distributive Lag (PARDL) methodology in the existence of different orders of integration. To estimate the long run relationship between the variables, we made use of the panel Johansen cointegration test, Pedroni test, Kao test and the Johansen Fisher cointegration test. Through the PARDL, the exchange rate and trade openness were found to be positive and statistically significant determinants of investment in SADC although statistically insignificant in the BRICS group. In addition, interest rates yielded insignificant results in the SADC region while, on the contrary, yielded a negative and statistically significant relationship in the BRICS group. The Granger causality test indicated a bi-directional causality in the exchange rate-investment and trade openness investment nexus for the SADC group while there was no causality in the BRICS group. It can be concluded that trade openness and exchange rate are key determinants of investment in the SADC region while interest rates are key in the BRICS group. It is therefore recommended that in order to attract investors and boost investment activities the SADC group need to focus more on exchange rate stability and trade openness while the BRICS group need to pay more attention to the flexibility of interest rates. This is beneficial on trading patterns, more for South Africa as it can be found in both groups.
495

Vyhledávací studie obchvatu města Hustopeče / Researching study of by-pass road of city Hustopeče

Tomešek, Zdeněk January 2012 (has links)
This graduation thesis deals about researching study of by-pass road of city Hustopeče, district of Břeclav, Southmoravian region. This city passes main road number 425, which should be connected with the by-pass road. The by-pass road will be designed as road of category S9,5/70 and will be situated west of the city. Terrain is undulated and composed of agricultural parcels. The main purpose of this by-pass road is significant burden of region traffic.
496

Revitalizace jezu ve Vranovicích na Svratce rybím přechodem / Revitalization of weir on Svratka river inVranovice with fish crossing

Jágr, Josef January 2012 (has links)
This present work deals with the design of revitalization measures for the weir in Uherčice (Vranovice) on the river Svratka. The current condition of weir constuction does not allow aquatic animals to migrate, weir constuction is transverse barrier. In this river section are found many fish species like barbel, vimba, nase and chub, for which is migration completely natural part of their behavior. There is concrete weir with a movable flap and on the right bank is located a small hydroelectric power plant. Close to hydroelectric power plant outlet is mouth of Šatava river. Weir revitalization consists of fish pass construction. Proposed fish pass is located on the right bank of the stream. There is a close-to-nature bypass channel that will ensure a continuity of water flow of already mentioned river Svratka between Věstonice lake and Rajhrad weir. Entrance to the fish pass will use a part of Šatava mount, then will continue in the artificial channel to the upstream part of Svratka river. Fish pass exit cannot breake the function of protective anti-flood embankment of Svratka river, hence there will be used block off construction. During condition of flooding will exist the possibility to shut down proposed fish pass.
497

Development of Acoustic Simulation Methods for Exhaust Systems / Utveckling av akustiska simuleringsmetoder för avgassystem

Friberg Femling, Christin January 2021 (has links)
Noise pollution is a growing concern due to its harmfulness to human health. Heavy vehicles powered by internal combustion engines stands for a major part of the environmental noise, why noise reduction is an increasing priority in enginve development. Within this study, an optimization problem is posed in order to minimize acoustic output without impairing the engine's overall performance. In our quest to diversify out noise reduction strategies, innovative ways of investigating this complex subject are essential. Here, we use simulations to investigate the possibility to reduce noise by component settings, as well as methods available to achieve that. Regarding the methods, the results indicates that a built in optimization tool within the simulation software used works well, despite the high complexity of the problem. A significant noise reduction is achieved when adjusting the settings of two of the parameters studied. This is a first attempt to tackle noise reduction in internal combustion engines by component settings. From the promising results, further improvements are expected as the simulation methods are refined and more components can be investigated accurately. / Bullerreducering är en allt viktigare fråga i samhället idag på grund av den negativa påverkan oljud kan ha på vår hälsa. Tunga fordon som driva av förbränningsmotorer står för den största delen av buller i vår omgivning, varför bullerreducering är ett alltmer prioriterat område vid utveckling av dessa motorer och fordon. I denna studie arbetar vi utifrån ett optimeringsproblem för att minimera ljudnivåerna utan att försämra motorns övergripande prestanda. I vår strävan att diversifiera strategier för bullerreducering behövs innovativa sätt att undersöka detta komplexa problem. Här används ett simuleringsverktyg för att undersöka möjligheterna att reducera ljudnivåerna genom att justera komponenternas beskaffenhet. Metoderna för att uppnå detta undersöks och utvärderas också. Resultaten pekar på ett inbyggt optimeringsverktyg i det simuleringsprogram som används hanterar optimeringsproblemet väl, trots dess höga komplexitet. En signifikant bullerreducering uppnås genom justering av inställningar hos två av de komponenter som undersökts. Detta är ett första försök att hantera bullerreducering inom förbränningsmotorer genom simulering av olika komponentinställningar. Med tanke på de lovande resultaten från denna första undersökning förväntas ytterligare förbättringar om simuleringsmodellen kan förfinas och fler komponenter kan undersökas.
498

Real-time Classification of Multi-sensor Signals with Subtle Disturbances Using Machine Learning : A threaded fastening assembly case study / Realtidsklassificering av multi-sensorsignaler med små störningar med hjälp av maskininlärning : En fallstudie inom åtdragningsmontering

Olsson, Theodor January 2021 (has links)
Sensor fault detection is an actively researched area and there are a plethora of studies on sensor fault detection in various applications such as nuclear power plants, wireless sensor networks, weather stations and nuclear fusion. However, there does not seem to be any study focusing on detecting sensor faults in the threaded fastening assembly application. Since the threaded fastening tools use torque and angle measurements to determine whether or not a screw or bolt has been fastened properly, faulty measurements from these sensors can have dire consequences. This study aims to investigate the use of machine learning to detect a subtle kind of sensor faults, common in this application, that are difficult to detect using canonical model-based approaches. Because of the subtle and infrequent nature of these faults, a two-stage system was designed. The first component of this system is given sensor data from a tightening and then tries to classify each data point in the sensor data as normal or faulty using a combination of low-pass filtering to generate residuals and a support vector machine to classify the residual points. The second component uses the output from the first one to determine if the complete tightening is normal or faulty. Despite the modest performance of the first component, with the best model having an F1-score of 0.421 for classifying data points, the design showed promising performance for classifying the tightening signals, with the best model having an F1-score of 0.976. These results indicate that there indeed exist patterns in these kinds of torque and angle multi-sensor signals that make machine learning a feasible approach to classify them and detect sensor faults. / Sensorfeldetektering är för nuvarande ett aktivt forskningsområde med mängder av studier om feldetektion i olika applikationer som till exempel kärnkraft, trådlösa sensornätverk, väderstationer och fusionskraft. Ett applikationsområde som inte verkar ha undersökts är det inom åtdragningsmontering. Eftersom verktygen inom åtdragningsmontering använder mätvärden på vridmoment och vinkel för att avgöra om en skruv eller bult har dragits åt tillräckligt kan felaktiga mätvärden från dessa sensorer få allvarliga konsekvenser. Målet med denna studie är att undersöka om det går att använda maskininlärning för att detektera en subtil sorts sensorfel som är vanlig inom åtdragningsmontering och har visat sig vara svåra att detektera med konventionella modell-baserade metoder. I och med att denna typ av sensorfel är både subtila och infrekventa designades ett system bestående av två komponenter. Den första får sensordata från en åtdragning och försöker klassificera varje datapunkt som antingen normal eller onormal genom att uttnyttja en kombination av lågpassfiltrering för att generera residualer och en stödvektormaskin för att klassificera dessa. Den andra komponenten använder resultatet från den första komponenten för att avgöra om hela åtdragningen ska klassificeras som normal eller onormal. Trots att den första komponenten hade ett ganska blygsamt resultat på att klassificera datapunkter så visade systemet som helhet mycket lovande resultat på att klassificera hela åtdragningar. Dessa resultat indikerar det finns mönster i denna typ av sensordata som gör maskininlärning till ett lämpligt verktyg för att klassificera datat och detektera sensorfel.
499

Separating, correlating, and exploiting anisotropic lineshapes for NMR structure determination in solids

Walder, Brennan J. 20 May 2015 (has links)
No description available.
500

Analog Implementation of DVM and Farrow Filter Based Beamforming Algorithms for Audio Frequencies

Miller, William H. 20 September 2018 (has links)
No description available.

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