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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
351

FULL-VIEW COVERAGE PROBLEMS IN CAMERA SENSOR NETWORKS

Li, Chaoyang 08 August 2017 (has links)
Camera Sensor Networks (CSNs) have emerged as an information-rich sensing modality with many potential applications and have received much research attention over the past few years. One of the major challenges in research for CSNs is that camera sensors are different from traditional scalar sensors, as different cameras from different positions can form distinct views of the object in question. As a result, simply combining the sensing range of the cameras across the field does not necessarily form an effective camera coverage, since the face image (or the targeted aspect) of the object may be missed. The angle between the object's facing direction and the camera's viewing direction is used to measure the quality of sensing in CSNs instead. This distinction makes the coverage verification and deployment methodology dedicated to conventional sensor networks unsuitable. A new coverage model called full-view coverage can precisely characterize the features of coverage in CSNs. An object is full-view covered if there is always a camera to cover it no matter which direction it faces and the camera's viewing direction is sufficiently close to the object's facing direction. In this dissertation, we consider three areas of research for CSNS: 1. an analytical theory for full-view coverage; 2. energy efficiency issues in full-view coverage CSNs; 3. Multi-dimension full-view coverage theory. For the first topic, we propose a novel analytical full-view coverage theory, where the set of full-view covered points is produced by numerical methodology. Based on this theory, we solve the following problems. First, we address the full-view coverage holes detection problem and provide the healing solutions. Second, we propose $k$-Full-View-Coverage algorithms in camera sensor networks. Finally, we address the camera sensor density minimization problem for triangular lattice based deployment in full-view covered camera sensor networks, where we argue that there is a flaw in the previous literature, and present our corresponding solution. For the second topic, we discuss lifetime and full-view coverage guarantees through distributed algorithms in camera sensor networks. Another energy issue we discuss is about object tracking problems in full-view coverage camera sensor networks. Next, the third topic addresses multi-dimension full-view coverage problem where we propose a novel 3D full-view coverage model, and we tackle the full-view coverage optimization problem in order to minimize the number of camera sensors and demonstrate a valid solution. This research is important due to the numerous applications for CSNs. Especially some deployment can be in remote locations, it is critical to efficiently obtain accurate meaningful data.
352

Multi-view hockey tracking with trajectory smoothing and camera selection

Wu, Lan 11 1900 (has links)
We address the problem of multi-view multi-target tracking using multiple stationary cameras in the application of hockey tracking and test the approach with data from two cameras. The system is based on the previous work by Okuma et al. [50]. We replace AdaBoost detection with blob detection in both image coordinate systems after background subtraction. The sets of blob-detection results are then mapped to the rink coordinate system using a homography transformation. These observations are further merged into the final detection result which will be incorporated into the particle filter. In addition, we extend the particle filter to use multiple observation models, each corresponding to a view. An observation likelihood and a reference color model are also maintained for each player in each view and are updated only when the player is not occluded in that view. As a result of the expanded coverage range and multiple perspectives in the multi-view tracking, even when the target is occluded in one view, it still can be tracked as long as it is visible from another view. The multi-view tracking data are further processed by trajectory smoothing using the Maximum a posteriori smoother. Finally, automatic camera selection is performed using the Hidden Markov Model to create personalized video programs. / Science, Faculty of / Computer Science, Department of / Graduate
353

Parallel Tomographic Image Reconstruction On Hierarchical Bus-Based And Extended Hypercube Architectures

Rajan, K 07 1900 (has links) (PDF)
No description available.
354

Temporal Closeness in Knowledge Mobilization Networks

Doan, William January 2016 (has links)
In this thesis we study the impact of time in the analysis of social networks. To do that we represent a knowledge mobilization network, Knowledge-Net, both as a standard static graph and a time-varying graph and study both graphs to see their differences. For our study, we implemented some temporal metrics and added them to Gephi, an open source software for graph and network analysis which already contains some static metrics. Then we used that software to obtain our results. Knowledge-Net is a network built using the knowledge mobilization concept. In social science, knowledge mobilization is defined as the use of knowledge towards the achievement of goals. The networks which are built using the knowledge mobilization concept make more visible the relations among heterogeneous human and non-human individuals, organizational actors and non-human mobilization actors. A time-varying graph is a graph with nodes and edges appearing and disappearing over time. A journey in a time-varying graph is equivalent to a path in a static graph. The notion of shortest path in a static graph has three variations in a time-varying graph: the shortest journey is the journey with the least number of temporal hops, the fastest journey is the journey that takes the least amount of time and the foremost journey is the journey that arrives the soonest. Out of those three, we focus on the foremost journey for our analysis.
355

Srovnání nástrojů pro animaci algoritmů / Comparison of algorithm animation tools

Čápek, Pavel January 2012 (has links)
The diploma thesis focuses on software tools which enable algorithm animation. In theoretical section of the work are introduced different ways how to present algorithms. Then the field of algorithm animation is described; it's history, development and current state. In the last part of theoretical section are shown possibilities how to use algorithm animation in teaching. Practical section of the thesis focuses on comparison of selected software tools. Selected tools are evaluated based on several criteria. The applications are then compared by multi-criteria decision making methods. Main goal of this thesis is to compare the selected software tools. Partial goals are to introduce advantages of using such applications compared to writing the algorithm in text form.
356

Development of a novel three-dimensional deformable mirror with removable influence functions for high precision wavefront correction in adaptive optics system

Huang, Lei, Zhou, Chenlu, Gong, Mali, Ma, Xingkun, Bian, Qi 27 July 2016 (has links)
Deformable mirror is a widely used wavefront corrector in adaptive optics system, especially in astronomical, image and laser optics. A new structure of DM-3D DM is proposed, which has removable actuators and can correct different aberrations with different actuator arrangements. A 3D DM consists of several reflection mirrors. Every mirror has a single actuator and is independent of each other. Two kinds of actuator arrangement algorithm are compared: random disturbance algorithm (RDA) and global arrangement algorithm (GAA). Correction effects of these two algorithms and comparison are analyzed through numerical simulation. The simulation results show that 3D DM with removable actuators can obviously improve the correction effects.
357

Neuronal Deep Fakes Data Driven Optimization of Reduced Neuronal Model

January 2020 (has links)
abstract: Neuron models that behave like their biological counterparts are essential for computational neuroscience.Reduced neuron models, which abstract away biological mechanisms in the interest of speed and interpretability, have received much attention due to their utility in large scale simulations of the brain, but little care has been taken to ensure that these models exhibit behaviors that closely resemble real neurons. In order to improve the verisimilitude of these reduced neuron models, I developed an optimizer that uses genetic algorithms to align model behaviors with those observed in experiments. I verified that this optimizer was able to recover model parameters given only observed physiological data; however, I also found that reduced models nonetheless had limited ability to reproduce all observed behaviors, and that this varied by cell type and desired behavior. These challenges can partly be surmounted by carefully designing the set of physiological features that guide the optimization. In summary, we found evidence that reduced neuron model optimization had the potential to produce reduced neuron models for only a limited range of neuron types. / Dissertation/Thesis / Doctoral Dissertation Neuroscience 2020
358

Algorithms for Computing Motorcycle Graphs

Yan, Lie 12 1900 (has links)
No description available.
359

Návrh antény PIFA pro GSM pásma / PIFA Antenna design for GSM band

Kollár, Marcel January 2011 (has links)
The main topic of this diploma thesis is a design of the PIFA antenna working in GSM bands. In the beginning there is a brief analysis of planar antennas. The thesis describes PIFA antenna and the techniques for minimization of dimensions of the antenna. Essential part of the thesis is dedicated to multicriterial optimalizaton of the antenna shape. The genetic algorithm programmed in the MATLAB enviroment cooperates with a full-wave solver CST to obrain desired impedance matching of the antenna its radiationt paterns. Also dimensions of the antenna can be minimized using the optimization procedure. Final part of the thesis compares measured data of the optimalized antenna with results obtained in CST Microwave Studio.
360

Nové digitální metody v procesu architektonického navrhování / New Digital Methods in Architecture Designing Process

Sirotek, Adam Unknown Date (has links)
The topic of this thesis is digital methods in process of architectonic designing, analysis, research and application of new methods. This thesis describes theoretical sources, which are useful for creating new digital methods. Thesis systematically describes existing methods and analyzes application on various projects. In thesis is also described research of new, own methods and preview of application.

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