This thesis examines the relationship between spot prices, futures prices, and ending stocks for storable commodities. We used Granger causality and DAGs to determine causal relationships and cointegration tests to determine long-run relationships. We use VAR/VECM and consider innovation accounting techniques to see how volatility in one market affects the price behavior and volatility in the other market. Results suggest that for agricultural commodities, innovations in futures price permanently increase the level of spot prices while accounting for much of spot price variance over time. For national oil, shocks to futures price decrease the level of spot price in the long run. In regional oil markets, there are transitory impulse responses. Futures price plays a small role in the volatility of spot prices for oil over time. Overall results are mixed, with oil suggesting futures markets may have a price stabilizing effect and agriculture commodities indicating spot price destabilization.

This report is a summary of the development of sensor integration for low-cost crash avoidance for over-land commercial trucks. The goal of the project was to build and test a system composed of low-cost commercially available sensors arranged on a truck trailer to monitor the environment around the truck. The system combines the data from each sensor to increase the reliability of the sensor using a probabilistic data fusion approach. A combination of ultrasonic and magnetoresistive sensors was used in this study. In addition, Radar and digital imaging were investigated as reference signals and possible candidates for additional sensor integration. However, the primary focus of this work is the integration of the ultrasonic and magnetoresistive sensors. During the investigation the individual sensors were evaluated for their use in the system. This included communication with vendors and lab and field testing. In addition, the sensors were modeled using an analytical mathematical model to help understand and predict the sensor behavior. Next, an algorithm was developed to fuse the data from the individual sensors. A probabilistic approach was used based on Bayesian filtering with a prediction-correction algorithm. Sensor fusion was implemented using joint a probability algorithm. The output of the system is a prediction of the likelihood of the presence of a vehicle in a given region near the host truck trailer. The algorithm was demonstrated on the fusion of an ultrasonic sensor and a magnetic sensor. Testing was conducted using both a light pickup truck and also with a class 8 truck. Various scenarios were evaluated to determine the system performance. These included vehicles passing the host truck from behind and the host truck passing vehicles. Also scenarios were included to test the system at distinguishing other vehicles from objects that are not vehicles such as sign posts, walls or railroads that could produce electronic signals similar to those of vehicles and confuse the system. The test results indicate that the system was successful at predicting the presence and absence of vehicles and also successful at eliminating false positives from objects that are not vehicles with overall accuracy ranging from 90 to 100% depending on the scenario. Some additional improvements in the performance are expected with future improvements in the algorithm discussed in the report. The report includes a discussion of the mapping of the algorithm output with the implementation of current and future safety and crash avoidance technologies based on the level of confidence of the algorithm output and the seriousness of the impending crash scenario. For example, irreversible countermeasures such as firing an airbag or engaging the brakes should only be initiated if the confidence of the signal is very high, while reversible countermeasures such as warnings to the driver or nearby vehicles can be initiated with a relatively lower confidence. The results indicate that the system shows good potential as a low cost alternative to competing systems which require multiple, high cost sensors. Truck fleet operators will likely adopt technology only if the costs are justified by reduced damage and insurance costs, therefore developing an effective crash avoidance system at a low cost is required for the technology to be adopted on a large scale.

The diploma project is involved in structure design of multipurpose house. It´s four floor building with one underground floor and flat roof. Structure system is reinforced concrete skeleton. Ceilings are solved as reinforced concrete slabs, spot supported by columns with circuit reinforcing beam.

The main goal of the diploma thesis is a proposal of alternative metal sheets joining technology which would replace the current technology of spot welding. Different variants have been proposed, and the one which suits the most, the technology of clinching, was compared to the existing one. The costs have been calculated and following results have been concluded: the return of investment of clinching press is about 2 years. In the case of handheld tongs it is 1 and a quarter of a year. Annual savings of clinching press are 234 485 Kč, and in the case of handheld tongs are 258 019 Kč.

In recent years two new diseases, brown spot and black pit, have been observed on potatoes in South Africa. Brown spot symptoms appear on the foliage as small brown lesions, whereas black pit symptoms appear on the tubers as small dark sunken lesions. In this study the causal organism of brown spot and black pit of potatoes in South Africa was determined. During initial isolation, one fungus and two bacteria were isolated, which were included in the trial. Only the treatments where the fungal isolate was used in inoculation resulted in the development of brown spot lesions. The causal organism of brown spot and black pit were identified as Alternaria alternata which is consistent with other research. To better understand the spread of Alternaria alternata between the plants and/or tubers a pot trial was conducted. It was observed that when planting an inoculated seed tuber brown spot may develop on foliage. But the daughter tubers harvested from plants infected with A. alternata will not necessarily develop black pit. Daughter tubers are most likely infected by A. alternata during harvesting and black pit lesions develop in high humidity in storage. Cultivar resistance is one of the most important measures in controlling plant diseases. Cultivar susceptibility of thirteen South African potato cultivars (Avalanche, Buffelspoort, BP1, Fabula, Fianna, Frodo, Hertha, Labadia, Lanorma, Mondial, Pentland Dell, Up-To-Date and Van Der Plank) was evaluated. Pot trials showed that all the evaluated cultivars are susceptible to infection by Alternaria alternata. Various crops (tomatoes, cabbage, mustard, wheat, oats, tobacco and maize) were assessed to determine the host range of Alternaria alternata (potato pathotype) in rotation crops in South Africa potato growing regions. Of the crops evaluated, the pathogen was able to infect only tomato crops. Only wheat, maize and oats can safely be used in the crop rotation in South Africa, as various potato pathogens attack cabbage, mustard and tobacco plants. This study will lead to a better understanding of brown spot and black pit diseases of potatoes in South Africa and globally. The study emphasise the need for further research which will help to reduce brown spot and black pit diseases of potato. / Dissertation (MSc Agric)--University of Pretoria, 2013. / gm2014 / Microbiology and Plant Pathology / unrestricted

Framträdande luftmaktsteorier förefaller i regel vara skrivna av stormaktsföreträdare. Ett implicit antagande att dessa teorier förutsätter betydande militär kapacitet och sofistikerad teknologi gör att de uppfattas som ”stormaktsteorier” som likt en klubba slår hårt mot motståndaren, med begränsad relevans för mindre stater som saknar stormakternas omfattande resurser. Luftmakt finns dock också i länder som kan betraktas som småstater. Även småstater kan – teoretiskt – antingen enskilt eller i en småstatsallians genom välriktade nålstick också skapa strategisk effekt med befintliga resurser.   Denna studie utmanar antagandet att luftmaktsteorier kan betraktas som antingen stormakts- eller småstatsteorier. Genom att pröva Robert Papes luftmaktsteori och Shaun Clarkes SPOT-paradigm i såväl stormakts- som småstatsperspektivet på ett gemensamt fall, Georgienkriget 2008 mellan Ryssland och Georgien, skapas ny kunskap om förklaringskraften hos respektive teori. Studien visar att Papes luftmaktsteori kan förklara stormakters användning av luftmakt, men belägg saknas för att den också kan förklara småstaters luftmaktsanvändning. Vidare saknas belägg för att Clarkes SPOT-paradigm kan förklara vare sig småstaters eller stormakters användande av luftmakt i det aktuella fallet. Däremot visar analysen att SPOT-paradigmet förutsätter ett visst mått av kvantitet och kvalitet, även hos småstater, för att omsättas i en skarp operation. Då ett mått på detta inte ges, bör SPOT-paradigmet främst betraktas som ett förhållningssätt till hur strategisk effekt kan skapas med tillgängliga resurser.

This diploma thesis deals with the problem of the criminalistic method of on-the-spot examination of the testimony, namely with particular questions of its theoretical definition as well as selected questions concerning its practical use within the activities of law enforcement authorities. The overall aim of this thesis is to give a comprehensive view of this institute and to present a detailed analysis of individual aspects of this method of forensic practice, as well as the subsequent identification of particular questions, problems and uncertainties that arise in this context. The first part focuses on the theoretical perspectives of the on-site examination of the testimony. Attention is brought to its process of constitution in Czechoslovak forensic science, its conceptual definition as well as differentiation from other methods of forensic practice. The second part of this thesis deals with selected practical questions related to the on- site examination of the testimony. In addition to the basic tactical principles elaborated by forensic theory, a substantial part of this chapter is devoted to the legal aspects of the on-site examination of the testimony, i.e. its legal regulation, its incorporation into the criminal justice system and possibilities of its use. This part also contains a...

As the demand for electricity increases throughout the globe while we want to reduce the use of fossil fuels, the need for renewable energy sources is bigger than ever. In countries where solar power makes up a large part of the total energy production, the overall electricity spot price level has become lower. This thesis investigates the underlying mechanism that drives the energy market, and in specific, how the solar power impacts the electricity spot price. We present results from studies made in other markets, and introduce a Regime Switching model for explaining the impact in Sweden. We show that an increase of photovoltaics power has a price lowering effect on the daily price pattern in price area SE3 and SE4.

Continuous improvement of image quality is one of the priorities in medical imaging. Therefore, development of a simulation tool allowing to generate realistic images would be of great value to understand better the impact of the components on the image quality metrics and to choose imaging set-ups or new design features to optimize output of existing systems and to prototype new ones and to formalize the link between objective and subjective image quality metrics. Therefore, the purpose of this project, was to contribute to adaptation and validation of an existing simulator for simulation of C-arm X-ray imaging. Firstly, the study of the existing simulation tool was performed to choose further development axes. Afterwards, preliminary estimations of simulation complexity by evaluating the number of photons for a given imaging examination were performed. Previous studies[1] showed the determining impact of focal spot on imaging performance (reducing the limiting spatial frequency in common examination conditions) of X-ray interventional imaging systems.  Therefore, the work focused on the improvements of source model, in particular realistic focal spot was defined and simulations of images with close-to-real sharpness were performed and compared to experimentally acquired images. Finally, a part of this project was dedicated to scatter study. An experimental set-up and "scatter map" analysis were designed to determine the scatter evolution as function of imaging field-of-view.  First simulations were also performed. [1] Samei, E., Ranger, N., MacKenzie, A., Honey, I., Dobbins, J. and Ravin, C. (2008). Detector or System? Extending the Concept of Detective Quantum Efficiency to Characterize the Performance of Digital Radiographic Imaging Systems 1. Radiology, 249(3), pp.926-937.

This licentiate thesis is concerned with residual stresses in aluminum alloy 6061-T6 resistance spot welded joint. Several topics related to mechanical strength of welded structures are treated such as; nugget size and microhardness and microstructures of weld zone and their influence on mechanical strength of welded structure, failure load measurement using tensile-shear test, resistance spot welding simulation, residual stress measurement by X-ray diffraction method and analysis effect of welding parameters on the mechanical strength and the residual stresses. To investigate the effect of resistance spot weld parameters on mechanical strength of welded structures, various welding parameters e.g. welding current, welding time and electrode force are selected to produce welded joints with different quality. According to the failure mode, the empirical equation was used to prediction of failure load base on nugget size and hardness of failure line. Microstructure study has been carried out to investigate microstructural changes in the welded joints. Microhardness tests are done to find hardness profiles due to microstructural changes and determine the minimum hardness. In addition, an electro-thermal-structural coupled finite element model and X-ray diffraction residual stress measurement have been utilized to analyze residual stresses distribution in weld zone. The electrical and thermal contact conductance, as mandatory factors are applied in contact area between electrode-workpiece and workpiece-workpiece to resolve the complexity of the finite element model. The physical and mechanical properties of the material are defined as thermal-dependent in order to improve the accuracy of the model. Furthermore, the electrodes are removed after holding cycle using the birth and death elements method. Moreover, the effect of welding parameters on maximum residual stress is investigated and a regression model is proposed to predict maximum tensile residual stresses in terms of welding parameters. The results obtained from the finite element analysis have been used to build up two back-propagation artificial neural network models for the residual stresses and the nugget size prediction. The results revealed that the neural network models created in this study can accurately predict the nugget size and the residual stresses produced in resistance spot weld. Using a combination of these two developed models, the nugget size and the residual stresses can be predicted in terms of spot weld parameters with high speed and accuracy. / <p>QC 20131014</p> / No