Controlling systems with uncertain dynamics is crucial in systems theory, especially for unmanned vehicles operating in challenging and unknown environments. One key application involves developing control methods to ensure collision-free trajectory tracking for unmanned surface vehicles (USVs) at sea. Modern control methods for such systems often encounter unwanted high-frequency oscillations, known as chattering, in the control signals. To address this, continuous approximations of discontinuous functions in the control law have proven effective in reducing chattering. This approach is integrated into a prescribed-performance control scheme, which has previously achieved asymptotic tracking for systems with uncertain dynamics. We employ Lyapunov stability analysis to determine if theoretical bounds for error performance can be smaller than the prescribed funnel functions when incorporating continuous approximations in a boundary-layer. For both first- and second-order systems, we show that system trajectories reach an arbitrarily small boundary-layer set in finite time. This allows us to derive a priori known error bounds that are smaller than the prescribed funnels. Simulations support the theoretical results, demonstrating a significant reduction in chattering while achieving asymptotic tracking errors two orders of magnitude smaller than the funnel functions.

La plaga Spodoptera frugiperda (Lepidopteroa: Noctuidae), es una especie polífaga que se encuentra difundida en todos los países americanos, provocando grandes pérdidas en los rendimientos de varios cultivos. La plaga Aphis craccivora causa daños a los cultivos anuales como alfalfa, habas, alcachofa, tomate y otros, al alimentarse de la savia, provoca deformaciones en los brotes tiernos y enrollamiento de las hojas y la muerte de la planta; asimismo, secreta una mielecilla que favorece el desarrollo de especies de hongos causantes de fumagina, afectando la fotosíntesis de la planta. Dentro de las alternativas de control con bajo impacto ambiental, se realizó la investigación para evaluar la susceptibilidad de estas dos plagas a la cepa Beauveria bassiana CBLE-265, producida por el Servicio Nacional de Sanidad Agraria (SENASA), con la finalidad de determinar la concentración letal al 50 % (CL50) y la concentración letal al 90 % (CL90) de la cepa frente a la plaga Spodoptera frugiperda y la plaga Aphis craccivora. Para definir las concentraciones se tuvo como base la dosis comercial del producto. Para la inoculación se asperjaron soluciones en diferentes concentraciones de Beauveria bassiana CBLE-265 con atomizadores manuales, a las larvas del I, II, y III estadío de Spodoptera frugiperda, después se colocaron en rejillas acrílicas con dieta artificial para su evaluación, mientras que para Aphis craccivora se asperjaron a las ninfas que estaban en maceteros con alfalfa para su evaluación. Utilizando el programa Probit se analizaron los datos de mortalidad del bioensayo a partir del 5to día hasta que lleguen a la etapa adulta, determinándose mediante proyecciones la concentración letal media y la concentración letal noventa. Para Spodoptera frugiperda estadío I, el valor del CL50 fue de 1,90 x 1024 conidias/g y el valor del CL90 fue de 2,30 x 1031 conidias/g, para estadío II, el valor del CL50 fue de 7,90 x 1024 conidias/g y el valor del CL90 fue de 9,10 x 1031 conidias/g. Para el estadio III, no se encontró letalidad con la cepa estudiada. Así como para las ninfas de Aphis craccivora no tuvo efecto alguno la cepa estudiada, por lo que se concluye que la cepa Beauveria bassiana CBLE-265 no es adecuada para el control de Plaga como Aphis Craccivora, no teniendo un efecto significativo. / -- The plague Spodoptera frugiperda (Lepidopteroa: Noctuidae), is a polyphagous species that is widespread throughout in all Americans countries, causing great losses in yields of several crops. The plague Aphis craccivora cause damage to the annual crops as alfalfa, beans, artichoke, tomato and others, by feeding on sap, causing deformations in the buds and the leaves curl and the death of the plant; also, excreted a honeydew that encourages the development of species of fungi causing fumagin, affecting the photosynthesis of the plant. Among the control alternatives with lower environmental impact, research was conducted to evaluate the susceptibility of these two plagues at the strain Beauveria bassiana CBLE-265, produced by the National Service of Agrarian Health (SENASA), in order to determine the LC50 and LC90 of the strain against the plague Spodoptera frugiperda and the plague Aphis craccivora. To define the concentrations was based on the commercial dose of the product. For inoculation were sprayed solutions at different concentrations of Beauveria bassiana CBLE-265 with manual spray to the larva of I, II and III stage of Spodoptera frugiperda, then placed in acrylic racks with artificial diet for its evaluation, whereas Aphis craccivora were sprayed at the nymphs, were in pots with alfalfa for its evaluation. Using the Probit program were analyzed mortality data from bioassay of the 5th day until they reach the adult stage, determined through projections the median lethal concentration and lethal concentration ninety. For stage I of Spodoptera frugiperda, the value of LC50 was 1,90 x 1024 conidia/g and the value of LC90 was 2,30 x 1031 conidia/g, for stage II, the value of LC50 was 7,90 x 1024 conidia/g and the value of LC90 was 9,10 x 1031 conidia/g. While for the nymphs of Aphis craccivora had no effect of the strain studied, so it is concluded that the strain of Beauveria bassiana CBLE-265 is not adequate to control both plagues, not having a significant effect.

The performance of a quadrotor can be significantly disturbed in presence of wind. In this paper, a simple-to-implement attitude controller is proposed to render a robust and accurate trajectory tracking in presence of disturbance and model uncertainties. The attitude controller design is based on Quantitative Feedback Theory (QFT). A fuzzy logic controller is further employed to provide satisfactory position trajectory tracking for the quadrotor. The performances of the controllers, in terms of disturbance rejection and trajectory tracking are experimentally studied. Finally, a flight scenario is performed to compare the performances of the designed QFT-Fuzzy control scheme with the ArduCopter controller. / May 2016

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science. Johannesburg, 2016. / The entomopathogenic nematodes (EPNs) have emerged as an important group of insect pests. The EPNs which comprise the Steinernema genus share symbiotic associations with Xenorhabdus bacteria. This research project focused on isolating and characterizing a novel and indigenous EPN isolate with its associated bacteria. The biological control potential of the nematode was investigated in the areas of host infectivity, infective juvenile recovery and progeny yield. These processes were investigated at three different factors. These included time, population size and temperature. The infectious abilities of the symbiotic bacteria were also evaluated without the contributions of the nematode partner at different bacterial doses, time intervals and temperature regimens. The genome of the bacteria was thereafter acquired through whole-genome sequencing and annotation techniques to elucidate the virulence mechanisms and genes involved in temperature adaptation. The species isolated in this investigation was novel. The species shared an 85 % maximum identity to and taxonomically grouped with the species Steinernema khoisanae. The two species shared a common ancestor but the extended branch length of the species under investigation substantiated its novelty. The EPNs infected hosts at different time intervals, population densities and temperature regimens. However, the EPNs performed these processes to different extents. Host mortality significantly increased with time. The EPNs also infected insect hosts at the two experimental temperatures. However, host mortality was higher at the temperature regimen of 20° C and lower at 30° C. Host infections were not significantly different at two tested population densities of 500 and 1000 infective juveniles. The levels of interaction between temperature and time and temperature population density were not statistically significant. The subsequent biological process of recovery was evaluated. The EPNs recovered at both population densities and temperature regimens. The infective juvenile recoveries were statistically insignificant at both population densities and temperature regimens. Since recovery was based on the mere presence of progeny infective juveniles, the percentages were high which contributed to the statistical insignificant findings. This also contributed to the non-significant interaction between population density and temperature. The last biological process investigated was the progeny yield of infective juveniles. The yields were significantly different between both population densities of infective juveniles and temperature regimens. Higher yields were obtained at the temperature regimen of 20° C and 25° C. Lower yields were obtained at 30° C. The unexpected finding was higher progeny yields obtained from the lower population densities of infective juveniles. This contributed to the significant interaction present between population density and temperature. The bacteria were thereafter molecularly characterized. The symbiotic bacteria shared a 99 % sequence similarity to the species Xenorhabdus sp. strain GDc328. It was interesting to observe the infectious abilities of the bacteria without contributions from the EPNs. This study was measured at different bacterial doses, time intervals and temperature regimens. Host mortality was achieved without contributions from the EPN. Host mortality significantly increased with bacterial dose and time. Host mortality was also significantly different between each temperature regimen. Higher mortalities were observed at 30° C and lower mortalities were observed at 20° C. The differences in the performance between the EPN-bacterial partnership and the bacteria alone were attributed to the manner in which adaptation occurred. Since the EPN-bacteria existed as a bi-partite entity, the partners evolved as a bi-partite complex. The bacteria were removed from the symbiosis and cultured individually. External factors may have re-shaped the performance of the bacteria at the different temperature regimens. To further understand the genetic mechanisms of temperature adaptation, host infectivity and symbiosis, the draft whole genome sequence of the bacteria was then acquired. The genome of the bacteria comprised several genes which encoded the flagella system of the bacteria. Also pairs of co-localized toxin-antitoxin genes were discovered. Temperature acclimatization was performed through different cold and heat shock proteins and lastly several molecular chaperones. The studies showed that the species Steinernema spp. and its associated symbiotic bacteria Xenorhabdus sp. strain GDc328 were good bio-pesticide candidates for application against endemic insect pests. / LG2017

CONTROL SYSTEMS IN FINANCIAL LAW RESUME JUDr. et Mgr. Lenka Veselá The proposed thesis deals with control systems, focusing on financial law. The theme of this work was chosen with regard to the current situation in society, taking into account the global economic crisis. Monitoring is an inseparable part of every well -functioning state therefore it is important to keep eye on this very rigorously and also address a further specifies control. Control is dynamically evolving topic that is still actual and cannot be found any area of human life, where it is not needed. As applied in a wide range of areas for this work was chosen just a part of law closer focusing on the area of financial law. Financial control, as presented in this work, is a broad definition of procedures for the control authorities in the individual sub-sectors of financial law. It can be defined as financial control in public administration, as well as a tax inspection, customs control, foreign exchange control in management. Financial control is also applied in the field of monetary law, fee law, banking law, etc. We could trace a system of financial control in all the various sub- sectors of the financial law. For this reason was chosen the view of the issue as to the control systems in financial law. The system is the set of all...

Increasing the efficiency and performance of internal combustion engines is always of interest in the automotive industry. One limiting factor to achieve this in gasoline combustion engines is the ignition timing which can not always be set where optimal ignition efficiency and performance is obtained. This is due to the knock phenomenon which is an abnormal combustion process that can damage the engine. Due to knock, a feedback controller which sets the ignition timing at the best possible value without the risk of harming the engine is required. In this thesis, a statistically driven knock intensity simulation environment based on the Burr Type XII distribution model was set up. In the simulation environment, different stochastic knock feedback controllers were implemented along with background noise estimation techniques used in the knock detection system. The feedback controllers were evaluated against the conventional knock controller commonly used in today’s engines in terms of ignition angle and transient response. The results from the simulation environment showed that a more advanced mean ignition angle can be achieved with stochastic based knock control strategies with the same knock-rate and without lessening the fast transient response achieved from the conventional strategy. To evaluate the results, some of the controllers were implemented in a four cylinder two-liter four stroke Volvo engine with similar results.

El presente proyecto de investigación se basa en el diagnóstico de un terminal portuario, en el que se propuso como herramienta de ingeniería la simulación de sistemas con el objetivo de cuantificar un ahorro significativo y lograr que el proceso de recepción y despacho de contenedores sea más eficiente. En el primer capítulo, se presenta la descripción de la metodología empleada para llevar a cabo una correcta simulación. Asimismo, explica 3 herramientas utilizadas para el diagnóstico como las estratégicas, de calidad y selección. Por último, menciona 2 casos de estudios que aplicaron la simulación de sistemas como propuesta de mejora. En el segundo capítulo, se describe la situación actual del terminal portuario. Asimismo, las herramientas estratégicas desarrolladas como el mapa de macro-procesos ,Balanced Scored Card y la matriz voz del cliente orientaron el enfoque del proyecto al área de operaciones, en especial al proceso de gestión de recepción y despacho de contenedores. Del mismo modo, se gestionaron los indicadores de dicho proceso a fin de plantear y seleccionar las causas raíces de sus problemas, mediante herramientas de calidad como Pareto, Ishikawa y los 5 porqués en los que se determinó que la sanción por multas por retener un camión más de 30 minutos dentro del terminal y el consumo innecesario de diésel de las maquinarias Rubber Tyred Gantry (RTG) son los más importantes. Finalmente, como herramienta de selección se emplea una matriz FACTIS, la que seleccionó la simulación de sistemas como la contramedida más relevante. En el tercer capítulo, se detalla la metodología empleada desde el proceso de recopilación de datos hasta la aplicación de la herramienta de optimización Optquest. Adicionalmente, se presenta la elaboración del modelo de simulación, así como la validación y el correcto análisis de resultados. La mejor alternativa de solución del modelo sugiere la compra de 2 balanzas y 2 garitas tanto de entrada como de salida. Finalmente, se describen 2 Quick Wins que están alineadas en reducir la estadía de un camión dentro del terminal y logar un consumo de diésel más eficiente a través de una buena señalización y un sistema de consumo híbrido. Por último, se realiza la evaluación técnica y económica. Por un lado, la primera indica que el tiempo dentro del terminal portuario mejorará en un 16.29%, cuantificado un ahorro anual de S/.514,403. Adicionalmente, el sistema de consumo híbrido presento un ahorro de S/.924, 218, es decir, 16.41% más eficiente frente al sistema actual. Por otro lado, la segunda sustenta la viabilidad del proyecto a través de un Valor Actual Neto de S/ 2, 761,271 y una tasa Interna de retorno del 18.75% en horizonte de 5 años. Finalmente, mostrando un periodo de recuperación de 3.09 años. / Tesis

La implementación de un sistema HVAC aplicado un centro de datos y telefonía, donde operan distintos equipos electrónicos que en conjunto son el medio principal de comunicación en determinada empresa, es un tema de suma importancia, ya que se hace uso de equipos de aire acondicionado obsoletos que operan ininterrumpidamente, lo que trae como consecuencia un alto consumo de energía y alto riesgo de fallo. Esta central está ubicada en una ciudad donde se presentan temperaturas elevadas de día y temperaturas adecuadas para el funcionamiento de los equipos de noche, característica del clima de este lugar que podría ser aprovechada para reducir costes en el consumo de energía. / Tesis

Liu Lu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 65-70). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.ii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- The Output Regulation Problem --- p.1 / Chapter 1.2 --- Control Design with Unknown High-frequency Gain Sign --- p.3 / Chapter 1.3 --- Contribution of the Thesis --- p.4 / Chapter 1.4 --- Thesis Outline --- p.5 / Chapter 2 --- Global Robust Stabilization of a Class of Nonlinear Systems --- p.6 / Chapter 2.1 --- Introduction --- p.7 / Chapter 2.2 --- Problem Formulation and Preliminaries --- p.8 / Chapter 2.3 --- Main Result --- p.11 / Chapter 2.4 --- An Example --- p.20 / Chapter 2.5 --- Application of Theorem 2.1 --- p.26 / Chapter 2.5.1 --- Chua's Circuit and Control Problem --- p.26 / Chapter 2.5.2 --- Solvability of the Control Problem --- p.28 / Chapter 2.5.3 --- Simulation Results --- p.32 / Chapter 2.5.4 --- Conclusion --- p.33 / Chapter 2.6 --- Conclusion --- p.36 / Chapter 3 --- Global Robust Output Regulation of Nonlinear Systems in Output Feedback Form --- p.39 / Chapter 3.1 --- Introduction --- p.40 / Chapter 3.2 --- Output Regulation Converted to Stabilization --- p.42 / Chapter 3.3 --- Main Result --- p.49 / Chapter 3.4 --- An Example --- p.55 / Chapter 3.5 --- Conclusion --- p.58 / Chapter 4 --- Conclusions --- p.62 / List of Figures --- p.64 / Bibliography --- p.65 / Biography

Chen Zhiyong. / "April 2005." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 205-215) / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.