The growing use of computers in modern control systems has led to the develop- ment of complex dynamic systems known as hybrid systems, which integrates both discrete and continuous systems. Given that hybrid systems are systems that operates in real time allowing for changes in continuous state over time periods, and discrete state changes across zero time, their modelling, analysis and verification becomes very difficult. The formal verifications of such systems based on specifications that can guar- antee their behaviour is very important especially as it pertains to safety critical applications. Accordingly, addressing such verifications issues are important and is the focus of this thesis. In this thesis, in order to actualise the specification and verification of hybrid systems, Interval Temporal Logic(ITL) was adopted as the underlying formalism given its inherent characteristics of providing methods that are flexible for both propositional and first-order reasoning regarding periods found in hardware and software system’s descriptions. Given that an interval specifies the behaviour of a system, specifications of such systems are therefore represented as a set of intervals that can be used to gain an understanding of the possible behaviour of the system in terms of its composition whether in sequential or parallel form. ITL is a powerful tool that can handle both forms of composition given that it offers very strong and extensive proof and specification techniques to decipher essential system properties including safety, liveliness and time projections. However, a limitation of ITL is that the intervals within its framework are considered to be a sequence of discrete states. Against this back- drop, the current research provides an extension to ITL with the view to deal with verification and other related issues that centres around hybrid systems. The novelty within this new proposition is new logic termed SPLINE Interval Temporal Logic (SPITL) in which not only a discrete behaviour can be expressed, but also a continuous behaviour can be represented in the form of a spline i.e. the interval is considered to be a sequence of continuous phases instead of a sequence of discrete states. The syntax and semantics of the newly developed SPITL are provided in this thesis and the new extension of the interval temporal logic using a hybrid system as a case study. The overall framework adopted for the overall structure of SPITL is based on three fundamental steps namely the formal specification of hybrid systems is expressed in SPLINE Interval Temporal Logic, followed by the executable subset of ITL, called Tempura, which is used to develop and test a hybrid system specification that is written in SPITL and finally a runtime verification tool for ITL called AnaTempura which is linked with Matlab in order to use them as an integrated tool for the verification of hybrid systems specification. Overall, the current work contributes to the growing body of knowledge in hybrid systems based on the following three major milestones namely: i. the proposition of a new logic termed SPITL; ii. executable subset, Tempura, integrated with SPITL specification for hybrid systems; and iii. the development of a tool termed Ana Tempura which is integrated with Matlab to ensure accurate runtime verification of results.

There is a growing demand for miniature, high-precision components and devices with micro-scale features for applications in biomedical systems, aerospace structures, and energy storage/conversion systems. Mechanical micromachining has become a leading approach to address this demand. In micromachining, a micro-scale cutting tool, such as a micro-endmill with a diameter as small as 10 um, is rotated by an ultra-high-speed (UHS) spindle (speeds greater than 60,000 rpm, reaching up to 500,000 rpm) to mechanically remove the material from a workpiece. Although micromachining resembles the traditional computer numerically controlled (CNC) machining processes, the micron-scale cutting tools, ultra-high-speed (UHS) spindles, and considerably tighter tolerance requirements bring unique challenges to micromachining.

Dynamic adaptivity of a computer system is its ability to modify the behavior according to the environment in which it is executed. It allows the system to achieve better performance, but usually requires specialized architecture and brings more complexity. The thesis presents an analysis and design of a framework that allows simple and fluent performance-based adaptive development at the level of functions and methods. It closely examines the API requirements and possibilities of integrating such a framework into the Scala programming language using its advanced syntactical constructs. On theoretical level, it deals with the problem of selecting the most appropriate function to execute with given input based on measurements of previous executions. In the provided framework implementation, the main stress is laid on modularity and extensibility, as many possible future extensions are outlined. The solution is evaluated on a variety of development scenarios, ranging from input adaptation of algorithms to environment adaptations of complex distributed computations in Apache Spark.

An increased mortgage cap was introduced in 2010, and as of May 1st 2016 an amortization requirement was introduced in an attempt to slow down house price development in Sweden. Fluctuations in the house prices can significantly influence macroeconomic stability, and with house prices in Stockholm rising even more rapidly than Sweden as a whole makes the understanding of Stockholm’s dynamics very important, especially for policy implications. Stockholm house prices between the first quarter of 1996 and the fourth quarter of 2015 is therefore investigated using a Vector Error Correction framework. This approach allows a separation between the long run equilibrium price and short run dynamics. Decreases in the real mortgage rate and increased real financial wealth seem to be most important in explaining rising house prices. Increased real construction costs and increased real disposable income also seem to have an effect. The estimated models suggest that around 40-50 percent, on average, of a short-term deviation from the long-run equilibrium price is closed within a year. As of the last quarter 2015, real house prices are significantly higher compared to the long run equilibrium price modeled. The deviation is found to be around 6-7 percent.

M.Phil. (Engineering Management) / Please refer to full text to view abstract

Pseudorandom sequences have many applications in fields such as wireless communication, cryptography and built-in self test of integrated circuits. Maximal length sequences (m-sequences) are commonly employed pseudorandom sequences because they have ideal randomness properties like balance, run and autocorrelation. However, the linear complexity of m-sequences is poor. This thesis considers the use of one-dimensional Cellular Automata (CA) to generate pseudorandom sequences that have high linear complexity and good randomness. The properties of these sequences are compared with those of the corresponding m-sequences to determine their suitability. / Graduate

This thesis presents a robust nonlinear model predictive controller (RNMPC), nominal nonlinear model predictive controller (NMPC) and single-loop proportional-integral-derivative (PID) controllers that are applied to a nonlinear model of a run-of-mine (ROM) ore milling circuit. The model consists of nonlinear modules for the individual process units of the milling circuit (such as the mill, sump and cyclone), which allow arbitrary milling circuit configurations to be modelled easily. This study aims to cast a complex problem of a ROM ore milling circuit into an RNMPC framework without losing the flexibility of the modularised nonlinear model and implement the RNMPC using open-source software modules. The three controllers are compared in a simulations study to determine the performance of the controllers subject to severe disturbances and model parameter variations. The disturbances include changes to the feed ore hardness, changes in the feed ore size distributions and spillage water being added to the sump. The simulations show that the RNMPC and NMPC perform better than the PID controllers with regard to the economic objectives, assuming full-state feedback is available, especially when actuator constraints become active. The execution time of the RNMPC, however, is much too long for real-time implementation and would require further research to improve the efficiency of the implementation. / Thesis (PhD)--University of Pretoria, 2009. / Electrical, Electronic and Computer Engineering / unrestricted

This study estimates an energy sector model consisting of interfuel substitution model and an aggregate energy and non-energy input demand system that incorporates short-run and longrun structural adjustment parameters. The study finds that all fuels in the energy aggregate are Morishima substitutes and that there are significant sectoral variations in magnitude of the elasticities. This indicates that economic instruments should be considered for energy policy but such policies should take into account not only differences in technology used across sectors but also the systematic distribution of costs when the relative prices of fuels change. Estimates of long-run elasticities for aggregate input demands indicate that energy-capital input ratios adjust faster than labour-capital input ratios. This suggests that investment policy should take into consideration tradeoffs between environmental gains and employment implicit in the production structure of the Malawian economy as both capital and labour demands have dynamic interactions with energy in the long-run with potential significant cumulative impacts on the environment. Using results and gaps noted from the partial equilibrium analysis, the study also evaluated general equilibrium impacts of reducing fossil and biomass fuel use by production activities while investing in more hydroelectricity. The results show that carbon emissions and forest resource depletion due to energy use, respectively, can be reduced by imposing environmental taxes aimed at inducing a shift from biomass and fossil fuels to hydroelectricity. More significantly, there are at least three dividends from inducing a shift in the energy mix in that the economy can attain GDP at least equal to the value before imposition of environmental taxes in addition to reducing carbon emissions and deforestation. Further, redistributing the environmental tax revenues to reduce direct taxes on households leads to better income distribution. These findings have direct policy relevance to the contemporary challenges to sustainable development under the added burdens of climate change. Most importantly is what developing countries can do to strategically position themselves in global agreements on financing for climate change adaptation and mitigation. The general equilibrium estimate of direct environmental cost associated with the use of fossil and biomass fuels is close to the moderate estimate of social cost of deforestation in the National Environmental Action Plan (NEAP). This is significant because in the absence of estimates of damages of secondary impacts of both carbon emissions and deforestation, the optimal energy tax as inferred from the general equilibrium model corresponds to the annual growth rate in the economy’s energy intensity. In addition, since short-run to medium term environmental impacts are critical when data on secondary damages are unavailable, it would be prudent to target growth in intensities of use of fuels that contribute to the economy’s footprint on the environment. The study also proposes alternatives to carbon emission taxation that could complement the current legislation on land use by agricultural estates. / Thesis (PhD)--University of Pretoria, 2010. / Agricultural Economics, Extension and Rural Development / unrestricted

This thesis elaborates and suggests marketing communication activities of the project Mattoni FreeRun. The activities to be used in the project are also accompanied by suggestions and improvements, which may inspire the project management to communicate ideas. The main idea of the project is to activate Mattoni FreeRun runners together with the brand, which aims to combine running and water Mattoni in one indivisible community, which will be perceived among runners and will long continue in their minds. Project Mattoni FreeRun will try to point out through selected activities mutual and almost integral connection between running and water in daily active, but also ordinary people's lives. The main thrust of the project Mattoni FreeRun is for its existence with its partners (RunCzech, Addidas) and some people, the so-called "ambassadors" to create a running community that will spread the idea between themselves and the general public.

The Master's Thesis is focused on optimization of inbound logistics of Toyota Peugeot Citroën Automobile. The aim of the Master's Thesis is analysis of current status of logistics in TPCA and detailed observation and research of logistic processes and routes with emphasis on the planning system. Factors affecting the decision making during logistics planning and process of information searching were identified with special attention for milk-routes. First chapter describes development of logistics a specifics of logistics in automotive industry. Following chapter analyse current status of logistics, types of logistic routes a system of the planning. Third chapter propose options for logistics planning optimization with help of improved information source obtaining, study the suitability of used logistics routes and test possibilities of utilization of commercial software. Last chapter of thesis is comparing logistics of TPCA and Škoda Auto.