Visual object tracking is the task of giving a unique ID to an object in a video frame, understanding whether it is present or not in a current frame and if it is present, precisely localizing its position. There are numerous challenges in object tracking, such as change of illumination, partial or full occlusion, change of target appearance, blurring caused by camera movement, presence of similar objects to the target, changes in video image quality through time, etc. Due to these challenges, traditional computer vision techniques cannot perform high-quality tracking, especially for long-term tracking. Almost all the state-of-the-art methods in object tracking use artificial intelligence nowadays, and more specifically, Convolutional Neural Networks. In this work, we present a Siamese based tracker which is different from previous works in two ways. Firstly, most of the Siamese based trackers takes the target in the first frame as the ground truth. Despite the success of such methods in previous years, it does not guarantee robust tracking as it cannot handle many of the challenges causing change in target appearance, such as blurring caused by camera movement, occlusion, pose variation, etc. In this work, while keeping the first frame as a template, we add five other additional templates that are dynamically updated and replaced considering target classification score in different frames. Diversity, similarity and recency are criteria to choose the members of the bag. We call it as a bag of dynamic templates. Secondly, many Siamese based trackers are vulnerable to mistakenly tracking another similar looking object instead of the intended target. Many researchers proposed computationally expensive approaches, such as tracking all the distractors and the given target and discriminate them in every frame. In this work, we propose an approach to handle this issue by estimate the next frame position by using the target's bounding box coordinates in previous frames. We use temporal network with past history of several previous frames, measure classification scores of candidates considering templates in the bag of dynamic templates and use tracker sequential confidence value which shows how confident the tracker has been in previous frames. We call it as robustifier that prevents the tracker from continuously switching between the target and possible distractors with this hypothesis in mind. Extensive experiments on OTB 50, OTB 100 and UAV20L datasets demonstrate the superiority of our work over the state-of-the-art methods.

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This report describes the study of a new approach to resolve pulse radar range bin ambiguity problem. The nature and the cause of the problem are discussed, and various methods presently used to solve this problem are presented. The report points out the disadvantages of these methods and, thus, introduces a new approach to resolve the radar range bin ambiguity problem by examining the reasonableness of the trajectory of the object being traced. Necessary algorithm and computer programs to support the study are given in Appendices I, II, and III.

No / Amblyopia results in a severe loss of positional information and in the ability to accurately enumerate objects (V. Sharma, D. M. Levi, & S. A. Klein, 2000). In this study, we asked whether amblyopia also disrupts the ability to track a near-threshold change in the trajectory of a single target amongst multiple similar potential targets. In the first experiment, we examined the precision for detecting a deviation in the linear motion trajectory of a dot by measuring deviation thresholds as a function of the number of moving trajectories (T). As in normal observers, we found that in both eyes of amblyopes, threshold increases steeply as T increases from 1 to 4. Surprisingly, for T = 1-4, thresholds were essentially identical in both eyes of the amblyopes and were similar to those of normal observers. In a second experiment, we measured the precision for detecting a deviation in the orientation of a static, bilinear "trajectory" by again measuring deviation thresholds (i.e., angle discrimination) as a function of the number of oriented line "trajectories" (T). Relative to the nonamblyopic eye, amblyopes show a marked threshold elevation for a static target when T = 1. However, thresholds increased with T with approximately the same slope as in their preferred eye and in the eyes of the normal controls. We conclude that while amblyopia disrupts static angle discrimination, amblyopic dynamic deviation detection thresholds are normal or very nearly so.

Von den frühen Tagen der Logfile-Analysen bis hin zur heutigen Verwendung von fortschrittlichen Tracking-Systemen wie Google Analytics hat sich die Nutzerverfolgung im Netz stetig weiterentwickelt. Doch während sie Websitebetreibern und Werbedienstleistern wertvolle Informationen liefert, wirft sie auch Fragen hinsichtlich des Privatsphäre- und Datenschutzes auf. Das Sammeln von persönlichen Daten und deren anschließende Verwendung ruft bei vielen Menschen Besorgnis hervor. Die Gesetzgeber reagieren darauf mit immer strengeren Datenschutzgesetzen, die das Aggregieren, Verarbeiten und Speichern von personenbezogenen Daten in der Webanalyse einschränken. Viele Unternehmen stehen daher vor der Herausforderung, ihre Tracking-Infrastruktur zu überdenken und an die Vorgaben anzupassen. Spätestens mit der bevorstehenden Abschaffung der sogenannten Third-Party-Cookies sind Websitebetreiber gezwungen, aktiv zu werden. Diese Arbeit zielt darauf ab, Tracking-Technologien und -Strategien hinsichtlich ihrer Zukunftssicherheit zu analysieren, um einen Kompromiss zwischen den Interessen der Gesetzgebung und den Anbietern sowie Nutzern von Tracking-Tools zu finden.:Inhaltsverzeichnis Abkürzungsverzeichnis 1. Einleitung 2. Datenschutzrechtliche Rahmenbedingungen 2.1 Geschichte des Datenschutzrechts 2.2 Die DSGVO: Auswirkungen und Grundsätze 2.3 Rechtliche Einordnung von Tracking-Technologien 3. Grundlagen des Webtrackings 3.1 Cookies 3.1.1 Funktionsweise 3.1.2 Unterscheidung nach Lebensdauer 3.1.3 Unterscheidung nach Quelle 3.1.4 Unterscheidung nach Nutzungsart 3.1.5 Third-Party-Cookies in der Kritik 3.2 Tracking-Pixel 3.3 Device Fingerprinting 3.4 Datenqualität in der Krise 4. Tracking-Strategien in der Praxis 4.1 CNAME-Cloaking 4.1.1 Implementierung 4.1.2 Risiken 4.1.3 Datenschutzrechtliche Einordnung 4.2 Server Side Tracking 4.2.1 Tagging mit dem Google Tag Manager 4.2.2 Risiken 4.2.3 Datenschutzrechtliche Einordnung 4.3 Shynet 4.3.1 Implementierung und Quellcode-Analyse 4.3.2 Risiken 4.3.3 Datenschutzrechtliche Einordnung 5. Status Quo und Ausblick 5.1 Google Consent Mode v2 5.2 Browseranbieter 5.3 Cookie Pledge 5.4 E-Privacy-Verordnung 6. Fazit Literaturverzeichnis Abbildungsverzeichnis Eigenständigkeitserklärung

International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / This paper analyzes the multi-path effects on telemetry equipment when it tracks the low-elevation flying target. Based on bias-axis mono-pulse technique, real time attenuation memory recursive Least-Squares Estimate as well as synthetic application of multiple source data, a comprehensive tracking method is proposed to eliminate the antenna shaking and reduce angle error caused by the multi-path effects. The method has been verified by field test. And the goal of smooth tracking of the low elevation target is eventually reached.

International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / This paper describes a novel Radiating Antenna Digital Pattern Analysis Test system (RADPAT). The RADPAT system consists of a portable computer and a compact electronic module (EM) that interfaces to the antenna under test . The EM has standardized inputs and outputs that make it easy to adapt to any antenna or antenna system. In addition to functioning as a standard radiation pattern recorder, the RADPAT system can record conically scanning (CONSCAN), single channel monopulse, or sequential lobing patterns with only one sweep per axis . Since the radiation pattern is recorded digitally, it can automatically extract actual system data such as the error slope, crosstalk, 3 or 10 dB beamwidths, sidelobe levels, boresight shift, etc.. The briefcase size RADPAT system is portable, weighing only 18 lbs (8 kg). This can be a significant advantage for either verification of system parameters or for troubleshooting a component or system problem . Thus, the RADPAT system combined with a standard pattern receiver or a telemetry receiver can provide instantaneous, on-site evaluation of the radiation characteristics of an installed antenna system.

Precognition can be defined as an anomalous correlation between current cognitive activity and a future event. Using behavioural and physiological measures, a number of previous studies have reported evidence for unconscious precognition during a variety of task conditions. The current thesis presents five experiments that were designed to test for unconscious precognition in the visual attention system while participants were engaged in a short term visual memory task. Each trial consisted of a study and test phase. In the study phase, participants were required to memorise an array of four stimuli while their eye movements were recorded. After a brief retention interval, a probe stimulus was presented for a yes/no recognition test. Two conditions were employed and were randomly determined. In the old condition, the probe was a stimulus viewed during study, termed the target. In the new condition, the probe was a novel stimulus. Experiments tested for the presence of precognition by examining whether there was a difference in the degree to which visual attention was allocated to items during the study phase of old and new trials. Two further studies were also carried out involving simulations that aimed to establish the extent to which a previously described artefact, termed the expectation bias, may impact on the results. Experiment 1 suggested that participants spent more time attending to target stimuli in old compared to new trials, a result that appeared to provide evidence for precognition. However, the data was considered unreliable due to inadequate randomisation. An exact replication of Experiment 1 was carried out in Experiment 2 with adequate randomisation, but failed to find evidence for precognition. Experiment 3A was a further attempt to replicate the preliminary results of Experiment 1 using more extensive randomisation procedures while Experiment 3B explored the potential role of the probe stimulus in generating a precognitive effect. However, no support for the precognitive hypothesis was found in either experiment. A fully balanced design was employed in Experiment 4 in order to control for potential confounds such as position and saliency effects. The results supported the precognitive hypothesis and suggested that less attention was allocated to targets in the old condition. An exploratory analysis also examined the relationship between several standardised stimulus variables and the apparent precognitive effect observed in Experiment 4. The results revealed a suggestive relationship between the size of the effect and item ratings of familiarity and visual complexity. Simulations of an expectation bias in Experiments 5A and 5B together with post-hoc examination of the data from the current series of experiments suggest that this artefact is not a plausible explanation for the observed effects. The thesis ends with a discussion of several methodological issues that may impact on both the interpretation of positive results and the conclusions that may be reached from this body of data as a whole. Finally, suggestions for further work are made.

Digital Holography Microscopy (DHM) is a new 3D measurement technique that exists since Charge Coupled Devices (or CCD cameras) allow to record numerically high resolution images. That opens a new door to the theory of holography discovered in 1949 by Gabor: the door that masked the world of digital hologram processing. A hologram is a usual image but that contains the complex amplitude of the light coded into intensities recorded by the camera. The complex amplitude of the light can be seen as the combination of the energy information (squared amplitude modulus) with the information of the propagation angle of the light (phase of the amplitude) for each point of the image. When the hologram is digital, this dual information associated with a diffractive model of the light propagation permits to numerically investigate back and front planes to the recorded plane of the imaging system. We understand that 3D information can be recorded by a CCD camera and the acquisition rate of this volume information is only limited by the acquisition rate of the unique camera. For each digital hologram, the numerical investigation of front and back regions to the recorded plane is a tool to numerically refocus objects appearing unfocused in the original plane acquired by the CCD. This thesis aims to develop general and robust algorithms that are devoted to automate the analysis process in the 3D space and in time of objects present in a volume studied by a specific imaging system that permits to record holograms. Indeed, the manual processing of a huge amount of holograms is not realistic and has to be automated by software implementing precise algorithms. In this thesis, the imaging system that records holograms is a Mach-Zehnder interferometer working in transmission and studied objects are either of biological nature (crystals, vesicles, cancer cells) or latex particles. We propose and test focus criteria, based on an identical focus metric, for both amplitude and phase objects. These criteria allow the determination of the best focus plane of an object when the numerical investigation is performed. The precision of the best focus plane is lower than the depth of field of the microscope. From this refocus theory, we develop object detection algorithms that build a synthetic image where objects are bright on a dark background. This detection map of objects is the first step to a fully automatic analysis of objects present in one hologram. The combination of the detection algorithm and the focus criteria allow the precise measurement of the 3D position of the objects, and of other relevant characteristics like the object surface in its focus plane, or its convexity or whatever. These extra relevant measures are carried out with a segmentation algorithm adapted to the studied objects of this thesis (opaque objects, and transparent objects in a uniform refractive index environment). The last algorithm investigated in this research work is the data association in time of objects from hologram to hologram in order to extract 3D trajectories by using the predictive Kalman filtering theory. These algorithms are the abstract bricks of two software: DHM Object Detection and Analysis software, and Kalman Tracking software. The first software is designed for both opaque and transparent objects. The term object is not defined by one other characteristic in this work, and as a consequence, the developed algorithms are very general and can be applied on various objects studied in transmission by DHM. The tracking software is adapted to the dynamic applications of the thesis, which are flows of objects. Performance and results are exposed in a specific chapter.

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