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关键词： Motion control   Linear programming   Robust control   Algorithms   Dynamical systems   Optimization   Equilibrium   Controllers   Computer science   Mathematics  

摘要： In control engineering, models of the system are commonly used for controller design. A standard control design problem consists of steering the given system output (or states) towards a predefined reference. Such a problem can be solved by employing feedback control strategies. By utilizing the knowledge of the model, these strategies compute the control inputs that shrink the error between the system outputs and their desired references over time. Usually, the control inputs must be computed such that the system output signals are kept in a desired region, possibly due to design or safety requirements. Also, the input signals should be within the physical limits of the actuators. Depending on the constraints, their violation might result in unacceptable system failures (e.g. deadly injury in the worst case). Thus, in safety-critical applications, a controller must be robust towards the modelling uncertainties and provide a priori guarantees for constraint satisfaction. A fundamental tool in constrained control application is the robust control invariant sets (RCI). For a controlled dynamical system, if initial states belong to RCI set, control inputs always exist that keep the future state trajectories restricted within the set. Hence, RCI sets can characterize a system that never violates constraints. These sets are the primary ingredient in the synthesis of the well-known constraint control strategies like model predictive control (MPC) and interpolation-based controller (IBC). Consequently, a large body of research has been devoted to the computation of these sets. In the thesis, we will focus on the computation of RCI sets and the method to generate control inputs that keep the system trajectories within RCI set. We specifically focus on the systems which have time-varying dynamics and polytopic constraints. Depending upon the nature of the time-varying element in the system description (i.e., if they are observable or not), we propose different sets of algori

关键词： Clinical trials   Algorithms   Visual perception   Morphology   Signal processing   Electrocardiography   Consent   Heart rate   Statistical analysis   Biology   Computer science   Electrical engineering   Engineering   Pharmacology  

摘要： Electrocardiograms (ECGs), which capture the electrical activity of the human heart, are widely used in clinical practice for detecting cardiac pathologies, and notoriously difficult to interpret. Many commonly prescribed medications, including antihistamines, antibiotics and antidepressants, can produce a complication known as ‘drug-induced long QT syndrome (diLQTS)’, characterised by a prolongation of the QT-interval on the ECG. It is associated with a life-threatening arrhythmia known as Torsade de Points (TdP)—the leading cause of sudden cardiac death in young, otherwise healthy people. Self-monitoring for diLQTS could therefore save many lives, but detecting it on the ECG is difficult, particularly at high and low heart rates, even for clinicians who routinely read ECGs. Whilst there have been attempts to automate ECG interpretation for several decades, the accuracy of these methods remains limited. In particular, automated QT measurement algorithms have proved unsatisfactory for detecting LQTS. A major challenge for automated QT algorithms is identifying the precise end of the T-wave (the terminal point), especially when the T-wave’s morphology is abnormal. This thesis is the first work to examine the ability of laypeople to interpret an ECG for drug-induced QT-prolongation monitoring, devise a novel ECG visualisation technique to enable them to interpret it accurately, and exploit an understanding of the human visual perceptual process to improve automated QT-prolongation detection. The approach draws from the field of pre-attentive processing theory in human vision, showing through several experiments that using pseudo-colour to expose QTinterval duration on the ECG significantly improves laypeople’s accuracy in detecting diLQTS at risk of TdP regardless of heart rate and T-wave morphology. An understanding of how humans use pseudo-colour to interpret ECG data is combined with clinical knowledge that considers the morphology of the T-wave to develop a novel,

关键词： Genetic algorithms   Artificial intelligence   Computer science  

摘要： Agent-based simulation of herding in financial markets varies in the herding and market mechanism. Replication studies are a cornerstone of the scientific method although it is not applied very often. The research aims to obtain a greater understanding of herding and the related stylised facts, assess the herding models’ reproducibility, and find ways to improve reproducibility by replicating two herding models. The first herding mechanism factor (Tedeschi et al., 2012) controls the extent of the neighbour’s influence on the expected returns and hence on the trading decisions. The market mechanism is an artificial market where agents submit either ask or bid orders into the order book, and they trade between themselves. The second replicating herding mechanism (Lux and Marchesi, 2000) is based on transition probabilities to decide whether agents are fundamentalists, optimistic or pessimistic chartists. The market mechanism is demand and supply. The first replicating study fails to produce the original results, whereas the second does have similar findings to the original paper. The second model’s description is done by following the recent STRESS guidelines for specifying models. The guidelines help to cover everything needed for describing the second model. Then features from the STRESS and ODD guidelines are combined to give a slightly revised guideline with a defined structure. This is considered to give an improvement. Both models have fat tails, and only the second model has volatility clustering. The behaviour of the second model that gives the volatility clustering is called on-off intermittency. This is analysed in detail to understand how the model enters and leaves periods of high volatility. The conclusions are that randomness causes the model to move into high volatility, which happens when the percentage of noise traders is high, and the price effect in the model soon returns the model back to low volatility.

关键词： Computer science   Artificial intelligence  

关键词： Computer science   Microbiology   Bioinformatics  

摘要： Modeling of bacteria growth under different environmental conditions provides a useful tool to predict food and consumer goods safety. This study introduces a flexible, unique, and data-driven model to predict the bacteria growth under different pH conditions, using a one-to-many Long-Short-Term Memory (LSTM) model. When compared with a benchmark model the proposed model showed a good predictive power for different bacteria behaviors. In addition to its predictive ability, the model architecture is flexible and can be adapted for different bacteria behavior patterns without additional prior assumptions.

关键词： Artificial intelligence   Computer science  

关键词： Computer science   Information technology  

ISBN: (数字)9781119821700;9781119821731 ISBN: (纸本)9781786306654

摘要： Computers and the Internet are an undeniable and inextricable part of our daily lives. This book is for those who wish to better understand how this came to be. It explores the technological bases of computers, networks, software and data management, leading to the development of four “pillars” on which the essential applications that have a strong impact on individuals and society are based: embedded systems, Artificial Intelligence, the Internet, image processing and vision. We will travel to the heart of major application areas: robotics, virtual reality, health, mobility, energy, the factory of the future, not forgetting the major questions that this digitization can raise. This book is the author"s testimony after fifty years spent in environments that are very open to new technologies. It offers perspectives on the evolution of the digital world that we live in.

关键词： Vegetation   Precipitation   Humidity   Forest & brush fires   Decision trees   Time series   Sensors   Computer science   Forestry   Meteorology  

摘要： Every year, thousands of forest fires occur in Canada; these fires pose risks to people's lives, health, and property and incur huge fire suppression costs. Accurate prediction of fire occurrences at finer temporal and spatial resolutions could aid in deploying fire-fighting resources efficiently. Timely deployment of resources at precise locations could help control fires at an earlier stage, which would reduce damage. We propose an approach to predicting forest fire occurrences at hourly intervals in small rectangular regions across Saskatchewan. To make these predictions, we pre-pared a suitable dataset, trained three machine learning classification models, namely Decision Tree, K-Nearest Neighbor (KNN), and Hidden Markov Model (HMM), and evaluated them using six performance measures. The hourly weather, vegetation, and forest fire ignitions datasets were integrated, cleaned, and transformed into time series classification format, to form the forest reoccurrence (FFO) dataset. Any values missing from the instances were estimated using appropriate imputation techniques. To remove class imbalance from the FFO dataset, we applied a domain-specific under sampling approach. Predicting whether or not a fire will occur at the current hour at a given location is a binary classification problem. A model is used to predict a label, either fire or non-fire. The inputs to the model are, the weather conditions for the previous 24 hours and the current hour, as well as the vegetation type at the location. Predicting fire occurrences is an imbalanced learning problem because the ratio of non-fires to fires is very high. Our experiments studied the performance of machine learning classifiers as this ratio was increased. The experiments used two training regimes. With imbalanced training (IMB), the ratio is identical for the training and testing sets. With balanced training (BAL), the ratio for the training set is fixed at50:50 while the ratio for the testing set is varied. Our r

关键词： Plating   Design specifications   Recycling   Algorithms   Automobile sales   High speed   Electric vehicles   Optimization   Metallurgy   Flexibility   Computer science   Materials science   Transportation  

摘要： Electrically excited synchronous machines (EESMs) are becoming an alternative to permanent magnet synchronous machines (PMSMs) in electric vehicles (EVs). This mainly attributes to the zero usage of rare-earth materials, as well as the ability to achieve high starting torque, the effectiveness to do field weakening and the flexibility to adjust power factor provided by EESMs. Furthermore, in case of converter failure at high speed, safety can be improved by shutting down the field current in EESMs. The purpose of this study is to investigate the potential application of EESMs in EVs. To achieve this aim, several topics are covered in this study. These topics are studied to confront the challenges before EESMs could become prevalent and to maximumly use the advantages of EESMs for EV applications. In control strategies, the challenge is to properly adjust the combination of stator and field currentsso that high power factor and minimum copper losses can be achieved. To tackle this, control strategies are proposed so that reactive power consumption and total copper losses are minimized. With the proposed strategies, the output power is maximized along the torque-speed envelope and high efficiency in field-weakening is achieved. In dynamic current control, due to the magnetic couplings between field winding and stator winding, a current rise in one winding would induce an electromagnetic force (EMF) in the other. This introduces disturbances in dynamic current control. In this study, a current control algorithm is proposed to cancel the induced EMF and the disturbances are mitigated. In machine design, high starting torque and effective field weakening are expected to be achieved in the same EESM design. To realize this, some criteria need to be satisfied. These criteria are derived and integrated into the design procedure including multi-objective optimizations. A 48 V EESM is prototyped during the study. In experimental verification, a torque density of 10 N·m/L is a

关键词： Capital punishment   Death penalty   Prison   Penitentiary   Settler colonialism   Antebellum Wisconsin   Criminal law  

摘要： This dissertation explores the central importance of capital punishment in the development of a criminal justice system in Wisconsin – first as part of the Michigan Territory (1818-36), then as a separate U.S. territory (1836-48), and, finally, throughout its early years as a state (1848-60). During the 1820s and 1830s, capital cases involving both Indian and white defendants helped to define the boundaries of legal jurisdiction on a settler-colonial frontier. During the 1840s, challenges to capital punishment became intertwined with the politics of state building. During the early 1850s, a series of specific and often controversial developments, such as the execution of wife-murderer John McCaffary in August 1851 and the construction of the first state prison in February 1852, led to the abolition of capital punishment in July 1853. Rather than stemming from a rising tide of abolitionist sentiment inspired by the northeastern anti-capital punishment movement, the abolition of the death penalty in Wisconsin constituted a highly contingent modification of the state’s criminal code, enacted despite stubbornly persistent ambivalence on the issue among the people and politicians of Wisconsin. Abolition of the death penalty would not end debate over the state’s criminal justice system. Following a series of high-profile murders and lynchings in 1854 and 1855, a vocal coalition argued that the abolition experiment had already failed. Insisting that only a return of the gallows could restore law and order, these critics argued that the so-called enlightened reform – based on the premises that certainty of punishment was more important than severity and that reformation was more important than revenge – had proven unable to curb the spread of violence engulfing the state. Though calls for restoration would ultimately be unsuccessful, a growing fear of lawlessness convinced authorities in Milwaukee and other cities across Wisconsin to completely overhaul their law enforcemen