Real-time aerial vehicle detection and tracking with depth-aided vision sensing

We study the problem of detecting and tracking flying objects in real-time with color and depth images. We improve the sparse part-based representation learning approach by utilizing depth data from depth vision sensor to achieve much faster detection speed while maintain high detection accuracy. We revised some of algorithms presented in part-based representation method to get marginally better performance. Then we invented a novel data preprocessing method, which is based on edge detection and contour selection to generate possible vehicle locations before the image is processed by classifier. This approach can be applied to any object with distinguishable parts in relatively fixed spatial configurations, and our target here is the flying vehicle at indoor environment. Since flying objects tend to change poses and locations fast and frequently, the detection algorithm needs to run fast so that the tracking algorithm can keep on tracking the detected object. We also use hardware acceleration tools to further increase algorithm speed. The results of vehicle localization and tracking are shown and a critical evaluation of our approaches is also presented

Photoperiod effects on circadian rhythms and puberty onset in African catfish Clarias gariepinus

ABSTRACT Photoperiod manipulation is routinely used in the aquaculture industry with the aim to enhance growth by manipulating the timing of reproduction in several commercially important temperate fish species. However, there are clear gaps in our understanding of how photoperiod is perceived by the circadian axis and transmitted to the brain to alter reproduction. Furthermore, due to the wide range of environments inhabited by fish, it is unlikely that one single organization exists. It is therefore believed that comparative studies of temperate species “models” with tropical species such as the African catfish (Clarias gariepinus) that adapted to different environments characterized by weaker light signals can help in such an aim. A number of studies were therefore performed in this PhD project to expand our knowledge on circadian biology and environmental physiological effects in African catfish. The first aim was to characterize the circadian melatonin system in this species (chapter 3). Results clearly showed that the control of melatonin production by the pineal gland was very different in the African catfish as compared to temperate species such as salmon and trout. Indeed, melatonin production appeared to mainly depend on light stimuli perceived by the eyes as opposed to salmonids where light directly perceived by the pineal gland regulates its own melatonin production within photoreceptors. The main evidence was obtained in ophthalmectomised fish that were unable to synthesize and release melatonin into the blood circulation during the dark period. This was the first time that such a decentralized organisation, similar in a way to the mammalian system, was found in any teleost species. In vitro results also supported such findings as African catfish pineal glands in isolation were not able to normally produce melatonin at night as usually seen in all other fish species studied so far. This indirectly suggested that pineal gland photo-sensitivity might be different in this tropical species. Further studies were performed to better determine the amount of light that can be perceived by the African catfish pineal gland depending on light transmittance though the skull (where the pineal gland is located). Surprisingly, it appeared that catfish cranium act as a stronger light filter than in other species resulting in lower light irradiance of the pineal gland. This could explain, although it still needs to be further confirmed, why African catfish photic control of melatonin produced by the pineal would have evolved differently than in temperate species. The work then focused on better characterizing diel melatonin production and endogenous entrainment through exposure to continuous photic regimes (continuous light, LL or darkness, DD) (chapter 4). Daily melatonin profiles of fish exposed to 12L:12D photoperiod (routinely used in indoor systems) confirmed low melatonin production at day (<10 pg/ml) and increase at night (50 pg/ml) as reported in most vertebrate species studied to date. Interestingly, results also showed that melatonin production or suppression can anticipate the change from night to day with basal melatonin levels observed 45 mins prior to the switch on of the light. These observations clearly suggest the involvement of a clock-controlled system of melatonin secretion that is capable of anticipating the next photophase period. Furthermore, when constant light (LL) was applied, day/night melatonin rhythms were abolished as expected due to the constant photic inhibition of AANAT activity (e.g. one of the enzyme responsible for the conversion of serotonin into melatonin). However when fish were exposed to constant darkness (DD), a strong endogenous melatonin rhythm (maintained for at least 4 days and 18 days in catfish and Nile tilapia respectively) was found, demonstrating once again the presence of robust circadian oscillators in this species. The next aim of the doctoral project was then to investigate circadian behaviour of catfish through locomotor activity studies (Chapter 5). African catfish is again a very interesting “model” due to its reported nocturnal activity rhythmicity as compared to most other teleosts species. Locomotor activity is considered as a very useful tool to elucidate the mechanisms of circadian organization in both invertebrates and vertebrates circadian. Results first confirmed the nocturnal activity rhythms in the species. Furthermore, clear circadian endogenous rhythms were observed under constant light (LL) or darkness (DD) during several days before losing rhythmicity. Interestingly, the activity levels varied depending on the stocking density. Finally, the last aim of this project was to test the effects of a range of photoperiodic manipulations on growth performances, sexual development and reproductive performances in African catfish reared from eggs to puberty. Results did not show any differences at the early sages (up to 90 days post hatching) in growth performances nor mortality (high) between control 12L:12D and LL treatments. In contrast, during the juvenile-adult period (from 120 to 360 DPH), significant growth effects were observed, as previously reported in other catfish species, with fish under LL displaying lower growth rate, food consumption and feed conversion efficiency in comparison to most other treatments (12:12, LL, 6:6, 6:18, 12-LL and LL-12) especially 12l:12D. However, no major effects of the photoperiodic treatments were observed with all fish recruited into puberty and developing gonads although differences in the timing of gametogenesis could be observed, especially a delay (circa 2 months) in females exposed to short daylength (6L:18D and 6L:6D). As for egg quality, egg diameter was the only parameter to differ between treatments (slightly larger in egg batch from LL treated females). Overall, none of the photoperiodic regime suppressed maturation in African catfish as opposed to some temperate species. The work carried out during this PhD project clearly advanced our understanding of circadian rhythmicity, light perception and effects of photoperiod on physiology in a tropical species. Future studies are now required to further characterise the circadian system and link it to evolutionary trends within vertebrates

Bioactivity/cytotoxicity of micro-/nano-materials and novel development of fiber-optic probes for single cell monitoring

Manufactured nano-/micro-materials (MNMs) have been widely used and their interactions with niche biological environment are highly concerned for both of their biohazardous and bioactive effects, whereas no available comprehensive evaluations or regulations have been provided yet. This dissertation thus focuses on three major aspects: 1) fundamental toxicity understandings of a typical MNMs (zinc oxide nanoparticles), 2) bioactivity evaluations of representative bioactive MNMs, and 3) development of novel micro-probes for high spatial resolution monitoring. Firstly, the NP\u27s concentration, irradiation, hydrodynamic size, and the localized pH, ionic strength, NP zeta-potential as well as dissolved oxygen levels were found correlated with the production of hydroxyl radicals (•OH). Thus a novel physicochemical mechanism was hypothesized on •OH generation from ZnO NPs to cast light on cytotoxic mechanisms of MNMs. Secondly, silicate-/borate-based nano-/micro-sized glass fibers showed good rehabilitation capability and the underlying mechanisms were revealed as that quicker ion releasing and glass conversion (into hydroxyapatite (HA)) are the key to promote cell proliferation and migration, thus the wound-healing effect. Thirdly, several types of fiber-optic-based probes were developed to better cope with high spatial resolution, niche biological environmental detection. Up to date the best probe is able to acquire a pH resolution of up to ~0.02 pH unit within biologically relevant pH range of 6.17 - 8.11 with fast sensing time of ~5 seconds. Real-time monitoring of single live human cells were also demonstrated and validated in cytotoxic studies to detect early-onset of cell deterioration on different stages, indicating its powerful potent on studies that focusing on MNMs and single cells --Abstract, page iv

A Triplet Track Trigger for Future High Rate Collider Experiments

The Large Hadron Collider (LHC) will have a major upgrade, called the High Luminosity LHC (HL-LHC), after which the proton beams will collide with around 7 times the design luminosity of the LHC (L = 10^34 cm^-2 s^-1). There are also studies being conducted for a 100 km large circular hadron collider, called the hadron-hadron Future Circular Collider (FCC-hh), for the post LHC era. It aims to collide proton beams with sqrt{s} = 100 TeV and L ∼30 x 10^34 cm^-2 s-^1. High luminosities allow for a detailed study of elusive processes, for example, Higgs pair production, thus enabling direct measurement of the trilinear Higgs self-coupling (λ). In this regard, a generator level study is presented in the thesis using the HH->bbbb physics channel assuming trigger-less readout at FCC-hh. An average pile-up of〈μ〉~1000 (200) is expected at the FCC-hh (HL-LHC) within a vertex region of ∼10 cm. A vast pile-up complicates object reconstruction and forces trigger systems to increase the thresholds of trigger objects to satisfy bandwidth and storage limitations of an experiment. Hence, there is a need for a trigger that makes a smart selection of hard collision events from a sea of pile-up collisions at the earliest possible stage of a trigger system. Track triggers are attractive candidates for such demanding situations as they have a very good pointing resolution (unlike calorimeter triggers) in addition to a good momentum resolution. A new concept, the Triplet Track Trigger (TTT) is proposed to be used at the very first trigger level. It consists of three closely spaced highly granular pixel (preferably monolithic sensors) detector layers at large radii (∼1 m). It uses a very simple and fast track reconstruction algorithm, that can be easily implemented in hardware. TTT tracking performance studies are presented using full Geant4 simulation and reconstruction for the ATLAS Inner Tracker (at HL-LHC) and reference tracker of the FCC-hh. Very good momentum and z-vertex resolution allow grouping of TTT tracks into several bins along the beam-axis, where jet clustering algorithms run in parallel to form TTT-jets. The TTT allows for excellent pile-up suppression for the HH->bbbb multi-jet signature in〈μ〉= 1000 conditions of FCC-hh. A rate reduction from the 40 MHz bunch collision frequency to 1 MHz (4 MHz) is achieved for a trigger efficiency of ∼60% (80%). A corresponding rough estimate on S/sqrt{B} ∼16 (19) is obtained with negligible systematic uncertainties and total integrated luminosity of 30 ab^-1

Oxygen-Free Museum Cases

Describes the design and construction of an oxygen-free, hermetically sealed display and storage case developed by the Getty Conservation Institute for the long-term protection of environmentally sensitive objects

Modern Telemetry

Telemetry is based on knowledge of various disciplines like Electronics, Measurement, Control and Communication along with their combination. This fact leads to a need of studying and understanding of these principles before the usage of Telemetry on selected problem solving. Spending time is however many times returned in form of obtained data or knowledge which telemetry system can provide. Usage of telemetry can be found in many areas from military through biomedical to real medical applications. Modern way to create a wireless sensors remotely connected to central system with artificial intelligence provide many new, sometimes unusual ways to get a knowledge about remote objects behaviour. This book is intended to present some new up to date accesses to telemetry problems solving by use of new sensors conceptions, new wireless transfer or communication techniques, data collection or processing techniques as well as several real use case scenarios describing model examples. Most of book chapters deals with many real cases of telemetry issues which can be used as a cookbooks for your own telemetry related problems

e-Sanctuary: open multi-physics framework for modelling wildfire urban evacuation

The number of evacuees worldwide during wildfire keep rising, year after year. Fire evacuations at the wildland-urban interfaces (WUI) pose a serious challenge to fire and emergency services and are a global issue affecting thousands of communities around the world. But to date, there is a lack of comprehensive tools able to inform, train or aid the evacuation response and the decision making in case of wildfire. The present work describes a novel framework for modelling wildfire urban evacuations. The framework is based on multi-physics simulations that can quantify the evacuation performance. The work argues that an integrated approached requires considering and integrating all three important components of WUI evacuation, namely: fire spread, pedestrian movement, and traffic movement. The report includes a systematic review of each model component, and the key features needed for the integration into a comprehensive toolkit

Scheduling Optimization And Coordination With Target Tracking Under Heterogeneous Networks In Automated Guided Vehicles (AGVs)

Throughout the development of the multi-AGV systems, prevailing research directions contain improving the performance of individual AGV, optimizing the coordination of multiple AGVs, and enhancing the efficiency of communication among AGVs. Current researchers tend to pay attention to one research direction at a time. There is a lack of research on the overall AGV system design that tackles multiple critical design aspects of the system. This PhD research addresses four key factors of the AGV system which are AGV prototypes, target tracking algorithms, AGVs scheduling optimization and the communication of a multi-AGV system. Extensive field experiments and algorithm optimization are implemented. Comprehensive literature review is conducted to identify the research gap. The proposed solutions cover the following three aspects of the AGV system design including communication between AGVs, AGVs scheduling and computer vision in AGVs.        For AGV communication, a network selection optimization algorithm is presented. An improved method for preventing convolutional neural network (CNN) immune from backdoor attack to ensure a multi-AGV system's communication security is presented. Meanwhile, a transmission framework for a multi-AGV system is presented. Those methods are used to establish a safe and efficient multi-AGV system's communication environment. For AGV scheduling, a multi-robot planning algorithm with quadtree map division for obstacles of irregular shape is presented. In addition, a scheduling optimization platform is presented. These methods are used to make a multi-AGV system have a shorter time delay and decrease the possibility of collision in a multi-robot system.Meanwhile, a scheduling optimization method based on the combination of a handover rule and the A* algorithm is proposed. The system properties that may affect the scheduling performance are also discussed. Finally, the overall performance of the newly integrated scheduling system is compared with other scheduling systems to validate its superiority and shortcomings in different corresponding work scenarios. Computer vision in AGV is investigated in detail. To improve an individual AGV's performance, an improved Camshift Algorithm has been proposed and applied to AGV prototypes. Furthermore, three deep learning models are tested under specific environments. In addition, based on the designed algorithm, the AGV prototype is able to make a convergent prediction of the pixels in the target area after the first detection of the object. Relative coordinates of the target can be located more accurately in less time. As tested in the experiments, the system architecture and new algorithm lead to reduced hardware cost, shorter time delay, improved robustness, and higher accuracy in tracking.        With the three design aspects in mind, a novel method for real-time visual tracking and distance measurement is proposed. Tracking and collision avoidance functions are tested in the designed multi-AGV prototype system. Detailed design procedure, numerical analysis of the measurement data and recommendations for further improvement of the system design are presented

Mechatronic Systems

Mechatronics, the synergistic blend of mechanics, electronics, and computer science, has evolved over the past twenty five years, leading to a novel stage of engineering design. By integrating the best design practices with the most advanced technologies, mechatronics aims at realizing high-quality products, guaranteeing at the same time a substantial reduction of time and costs of manufacturing. Mechatronic systems are manifold and range from machine components, motion generators, and power producing machines to more complex devices, such as robotic systems and transportation vehicles. With its twenty chapters, which collect contributions from many researchers worldwide, this book provides an excellent survey of recent work in the field of mechatronics with applications in various fields, like robotics, medical and assistive technology, human-machine interaction, unmanned vehicles, manufacturing, and education. We would like to thank all the authors who have invested a great deal of time to write such interesting chapters, which we are sure will be valuable to the readers. Chapters 1 to 6 deal with applications of mechatronics for the development of robotic systems. Medical and assistive technologies and human-machine interaction systems are the topic of chapters 7 to 13.Chapters 14 and 15 concern mechatronic systems for autonomous vehicles. Chapters 16-19 deal with mechatronics in manufacturing contexts. Chapter 20 concludes the book, describing a method for the installation of mechatronics education in schools