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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.
61

Ownership Masks, Evolving Views and Cooperative Templates in Template Tracking

Angold, Alan January 2003 (has links)
A template tracker is a tracker based on matching a pre-initialised view of an object with the object's view in an image sequence. Using an error function, the intensity difference between the template view and the templated region in the image is measured. This error measure is used as the basis for a template alignment algorithm that will adjust the template's pose to more accurately register the template view with the view of the object in the image. Some significant problems present themselves with this simple tracker. Extraneous, or non-object, pixels within the template boundaries can cause bias in the registration of the template. Partial occlusions of the object's view in the image can also cause serious bias in the template's pose. Beyond simple occlusions there are transits of occlusions across an object. Occlusion transits are significant because over time they can occlude the entire object in an incremental fashion. If initially the template view is not completely known this kind of occlusion can easily cause a total tracking failure for an object. In this thesis three enhancements of the basic template tracker are proposed: Ownership Masks, Cooperative Templates, and Evolving Views. Ownership Masks are aimed at eliminating the extraneous pixels from the template view. Cooperative templates are used to separate the intensity probabilities when more than one template covers a pixel. Building upon both Ownership Masks and Cooperative Templates, Evolving Views update the template views when occlusion transits are a problem. With these enhancements we have been able to increase the accuracy of tracking objects where large portions of a template contain background pixels. Also occlusions and some types of unocclusions can be detected and discriminated. Finally, some failures in the basic tracker due to occlusion transits have been overcome.
62

Formulating Complex Queries Using Templates

Zhang, Hao 21 January 2009 (has links)
While many users have relatively general information needs, users who are familiar with a certain topic may have more specific or complex information needs. Such users already have some knowledge of a subject and its concepts, and they need to find information on a specific aspect of a certain entity, such as its cause, effect, and relationships between entities. To successfully resolve this kind of complex information needs, in our study, we investigated the effectiveness of topic-independent query templates as a tool for assisting users in articulating their information needs. A set of query templates, which were written in the form of fill-in-the-blanks was designed to represent general semantic relationships between concepts, such as cause-effect and problem-solution. To conduct the research, we designed a control interface with a single query textbox and an experimental interface with the query templates. A user study was performed with 30 users. Okapi information retrieval system was used to retrieve documents in response to the users’ queries. The analysis in this paper indicates that while users found the template-based query formulation less easy to use, the queries written using templates performed better than the queries written using the control interface with one query textbox. Our analysis of a group of users and some specific topics demonstrates that the experimental interface tended to help users create more detailed search queries and the users were able to think about different aspects of their complex information needs and fill in many templates. In the future, an interesting research direction would be to tune the templates, adapting them to users’ specific query requests and avoiding showing non-relevant templates to users by automatically selecting related templates from a larger set of templates.
63

Formulating Complex Queries Using Templates

Zhang, Hao 21 January 2009 (has links)
While many users have relatively general information needs, users who are familiar with a certain topic may have more specific or complex information needs. Such users already have some knowledge of a subject and its concepts, and they need to find information on a specific aspect of a certain entity, such as its cause, effect, and relationships between entities. To successfully resolve this kind of complex information needs, in our study, we investigated the effectiveness of topic-independent query templates as a tool for assisting users in articulating their information needs. A set of query templates, which were written in the form of fill-in-the-blanks was designed to represent general semantic relationships between concepts, such as cause-effect and problem-solution. To conduct the research, we designed a control interface with a single query textbox and an experimental interface with the query templates. A user study was performed with 30 users. Okapi information retrieval system was used to retrieve documents in response to the users’ queries. The analysis in this paper indicates that while users found the template-based query formulation less easy to use, the queries written using templates performed better than the queries written using the control interface with one query textbox. Our analysis of a group of users and some specific topics demonstrates that the experimental interface tended to help users create more detailed search queries and the users were able to think about different aspects of their complex information needs and fill in many templates. In the future, an interesting research direction would be to tune the templates, adapting them to users’ specific query requests and avoiding showing non-relevant templates to users by automatically selecting related templates from a larger set of templates.
64

Eye Tracking System

Lin, Jar-Way 21 July 2003 (has links)
¡@¡@It has been for a long time to develop systems of eye control, which are related to a variety of techniques, such as signal/image processing, characteristics of face identifying/tracking, action-mappings, etc. In terms of implementations, the acquisition of data can be done by either special instruments or by general devices. Such systems can be applied to many fields, for instance, military, medicine, entertainments, and other tasks that are fitted. And for the similar system, the performance differs due to the disparity of distinct situations and the way to use it. ¡@¡@In this thesis, we present a system that takes a sequence of images of a user as inputs, and then integrates methods of elliptical model of head, dual states of eyes, deformable templates, and the most yield filter to track the user¡¦s eyes. A coarse-to-fine strategy is used to rapidly locate the region of eyes and to get the information of eyes in order to translate into corresponding operations on machines. The experiment shows that our system is quite robust and fast so that it can help people who are unable to use physical body well.
65

Inquiry-based learning templates for creating online educational paths

Davis, Sarah Alice 30 October 2006 (has links)
Walden's Paths, created by the Center for the Study of Digital Libraries, provides a mechanism for leveraging student learning with the incredible amount of educational material on the web by organizing selected web pages into a structured learning activity. Applying specialized templates to the creation of Walden's Paths can aid a path author in creating pedagogically sound, Web-based activities, by assisting in the collection of information and organization of the activity. Authoring templates may be based on established educational frameworks, learning theories or specific activity type. This research project investigates how using pedagogically based templates affects the authoring process for paths created using Walden's Paths. A template based on the educational framework Inquiry-Based Learning was created and tested by a group of users to determine what effects the template has on creating paths as compared to creating similar paths using the existing Walden's Paths interface.
66

Effizient Programmieren mit der C++ Standard Template Library

Guenther, Marco 07 May 2003 (has links)
- Einführung in die Arbeit mit Templates - Vorstellung der in der STL enthaltenen Templates - Beispiele für deren Nutzung
67

Fabrication and Characterization of CIS/CdS and Cu2S/CdS Devices for Applications in Nano Structured Solar Cells

Jayaraman, Visweswaran 01 January 2005 (has links)
Nano structured solar cells provide an opportunity for increased open circuit voltages and and short circuit currents in solar cells due to quantum confinement of the window and absorber materials and an increase in the optical path length for the incident light. In this study, both bulk and nano heterojunctions of CIS/CdS and Cu2S/CdS devices have been fabricated and studied on plain glass substrates and inside porous alumina templates to compare their performance. The devices have also been characterized SEM, XRD and JV measurements. The J-V curves have also been analyzed for series resistance, diode ideality factor and reverse saturation current density.
68

Nuclei/Cell Detection in Microscopic Skeletal Muscle Fiber Images and Histopathological Brain Tumor Images Using Sparse Optimizations

Su, Hai 01 January 2014 (has links)
Nuclei/Cell detection is usually a prerequisite procedure in many computer-aided biomedical image analysis tasks. In this thesis we propose two automatic nuclei/cell detection frameworks. One is for nuclei detection in skeletal muscle fiber images and the other is for brain tumor histopathological images. For skeletal muscle fiber images, the major challenges include: i) shape and size variations of the nuclei, ii) overlapping nuclear clumps, and iii) a series of z-stack images with out-of-focus regions. We propose a novel automatic detection algorithm consisting of the following components: 1) The original z-stack images are first converted into one all-in-focus image. 2) A sufficient number of hypothetical ellipses are then generated for each nuclei contour. 3) Next, a set of representative training samples and discriminative features are selected by a two-stage sparse model. 4) A classifier is trained using the refined training data. 5) Final nuclei detection is obtained by mean-shift clustering based on inner distance. The proposed method was tested on a set of images containing over 1500 nuclei. The results outperform the current state-of-the-art approaches. For brain tumor histopathological images, the major challenges are to handle significant variations in cell appearance and to split touching cells. The proposed novel automatic cell detection consists of: 1) Sparse reconstruction for splitting touching cells. 2) Adaptive dictionary learning for handling cell appearance variations. The proposed method was extensively tested on a data set with over 2000 cells. The result outperforms other state-of-the-art algorithms with F1 score = 0.96.
69

Reikalavimų specifikavimo šablonais modelis ir jo programinis prototipas / Template based model for requirement specification and its prototype

Morkevičius, Albertas 23 June 2014 (has links)
Darbe pristatomas reikalavimų specifikavimo šablonais modelis. Aptariama aukštos kokybės reikalavimų proceso nauda kuriamoms sistemoms. Pateikiami išanalizuotų reikalavimų specifikacijos dokumento standartų ir reikalavimų inžinerijos programinių įrankių detalios analizės rezultatai. Pristatoma koncepcija geriau užtikrinanti reikalavimų identifikavimo ir specifikavimo kokybę - sumodeliuotas reikalavimų specifikacijos modelis, panaudojantis Volere reikalavimų surinkimo šabloną, pritaikant reikalavimų specifikavimo programinės įrangos įrankį Telelogic Doors. Sukurto prototipo pagalba, sistema automatizuoja reikalavimų surinkimo procesą, sumažindama 30 % vartotojo veiksmų, taip sudarydama didesnį vartotojo darbo našumą ir efektyvumą reikalavimų specifikavimo procese. / The main object of this thesis is to analyze requirements specification templates and requirements management tools and realize model prototype using requirements specification templates. There are analyze of requirements templates and requirements managing tools results in considering about a gain of high quality requirements process. To introduce a conception witch supports clearly requirement specification process – the model of Volere requirements specification template adopting Telelogic Doors requirements managing tool. Model realized in Doors using DXL - Doors eXtension Language. Created prototype reduce 30% of users activities and lets user to get more efficiency and productivity in requirements specification process.
70

Metal Nanoparticles/Nanowires Self-assembly on Ripple Patterned Substrate

Ranjan, Mukesh 07 October 2011 (has links) (PDF)
Plasmonic properties of self-assembled silver nanoparticles/nanowires array on periodically patterned Si (100) substrate are reported with special attention on the mechanism of nanoparticles self-assembly. The advantage of this bottom up approach over other self-assembling and lithographic methods is the flexibility to tune array periodicity down to 20 nm with interparticle gaps as low as 5 nm along the ripple. Ripple pattern have shallow modulation (~2 nm) still particles self-assembly was observed in non-shadow deposition. Therefore adatoms diffusion and kinetics is important on ripple surface for the self-assembly. PVD e-beam evaporation method used for deposition has proven to be superior to sputter deposition due to lower incident flux and lower atom energy. It was found that particles self-assembly largely dependent on angle of incidence, substrate temperature, and deposition direction due to ripple asymmetric tilt. Ostwald ripening observed during annealing on ripples substrate has striking dependency on ripple periodicity and was found to be different compared to Ostwald ripening on flat Si surface. In-situ RBS measurements of deposited silver on flat and rippled substrate confirmed different sticking of atoms on the two surfaces. The difference between maximum and minimum of the calculated local flux show a peak at an incidence angle of 70o with respect to surface normal. This explains the best alignment of particles at this angle of incidence compare to others. Self-assembled nanoparticles are optically anisotropic, i.e. they exhibit a direction dependent shift in LSPR. The reason of the observed anisotropy is a direction dependent plasmonic coupling. Different in plane and out of the plane dielectric coefficients calculated by modelling Jones matrix elements, confirms that nanoparticle/nanowire array are biaxial anisotropic (ex ¹ ey ¹ ez). The nanoparticles are predominantlyinsulating while nanowires are both metallic and insulating depending on the dimension. Silver nanoparticles/nanowires self-aligned on pre-patterned rippled substrate are presented for the first time as an active SERS substrate. Anisotropic SERS response in such arrays is attributed to different field enhancement along and across the ripples. Strong plasmonic coupling in elongated nanoparticles chain results in significantly higher SERS intensity then spherical nanoparticles/nanowires and non-ordered nanoparticles. Higher SERS intensity across the nanowires array in comparison to along the array (bulk silver) confirms electromagnetic field enhancement (hot-junction) is responsible for SERS phenomenon. Self-assembly of cobalt nanoparticle on ripple pattern substrate is also reported. Due to less adatom mobility and higher sticking cobalt self-assembly is possible only at much higher temperature. A strong uniaxial magnetic anisotropy was observed not observed for non ordered cobalt particles.

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