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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.
21

Digitally Modulated Light for Multiple Fluorescence Excitation in Capillary Electrophoresis Detection System

Wu, Dai-yang 14 February 2008 (has links)
This research has successfully developed a multiple fluorescence detection method for high throughput capillary electrophoresis detection using a digitally-modulated light source and a spectrum detection system. A commercial available LCD (liquid crystal device) projector is adoped to replace the spacially-filttered light source (Hg lamp) in a conventional fluorescence microscopy. The LCD projector can be digitally controlled by a computer to create the three primary colors of RGB (red, green, and blue) for fluorescence excitation in the analytes. The emitted light from the fluorescent samples is then collected using a UV-VIS-NIR spectrometer through a ultimode fiber. Delicate optical components, such as filter wheel or acousto-optic filtering system, for filtering different excitation light sources can be excluded with this simple and novel approach. In addition, the desired wavelength for the excitation light can be selected quickly and smoothly without vibration problems come with the mechanical optical components. Three fluorescent dyes (Atto 647N, Rhodamine B, Fluorescein) with different excitation and emission wavelength has been used to demonstrate the proposed digitally-modulated light source system for high throughput CE system. The optimal operation conditions for obtaining best detection signal-to-noise ratio for different fluorescence dyes are firstly determined. In addition, the current study proposes a mixed-color light (visually in purple) composed of two specific primary lights (red and blue) to simultaneously excite a mixed sample composed of two fluorescent dyes (Atto 647N and FITC). Separation and detection of the mixed fluoresce samples using a single excitation illumination using the proposed digital-modulated CE system is successfully demonstrated. Finally, a single-strand DNA biosample is used to confirmed the proposed system is feasible of adopting in the bio-analytical applications. The technique proposed in this study has shown its potential to be a high throughput CE detection system.
22

GSC-Based Equalizer for CP-Free SIMO OFDM Systems with Oblique Projector

Tan, Mu-Chen 08 August 2008 (has links)
In orthogonal frequency division multiplexing (OFDM) systems, when transmitted blocks of signal through the multipath channel, the present transmitted blocks of signal will be interfered by the previous one due to the effect of channel delay spread. In order to solve this problem, conventionally we introduce a guard interval in transmitted blocks of signal to avoid inter-block interference (IBI). The most popular methods of the guard interval insertion are zero-padding (ZP) and cyclic prefixing (CP). ZP insert the guard interval at the end of the transmitted blocks of signal, in which all elements are zeros. The length of this interval must be equal to or greater then the channel order. In this way we can avoid IBI, at the expense of lossing the orthogonality between subcarrier due to the multipath channel. However, we can use CP to cope whit this problem. In CP we copy the 25% length at the end of the transmitted blocks of signal, and put it in front of the transmitted block to suppress the inter-block interference and inter-carrier interference. In this thesis, we consider OFDM system without the guard interval, hence the received signal contains IBI and ICI. In our proposed scheme, we use an oblique projector (OB) to suppress IBI at first. Then we combine it with a generalized sidelobe canceller (GSC) based equalizer [1] for ICI supppression and demodulate the receiver signal. In computer simulations, we use the GSC-based equalizer with oblique projector to suppress IBI/ICI in the time-invariant channel and time-varying channel. As we will see, in the CP-free OFDM system, the oblique projector can suppress IBI exactly. Moreover we can get better performance in channel with larger order.
23

A CAMERA-BASED ENERGY RELAXATION FRAMEWORK TO MINIMIZE COLOR ARTIFACTS IN A PROJECTED DISPLAY

Sanders, Nathaniel 01 January 2007 (has links)
We introduce a technique to automatically correct color inconsistencies in a display composed of one or more digital light projectors (DLP). The method is agnostic to the source of error and can detect and address color problems from a number of sources. Examples include inter- and intra-projector color differences, display surface markings, and environmental lighting differences on the display. In contrast to methods that discover and map all colors into the greatest common color space, we minimize local color discontinuities to create color seamlessness while remaining tolerant to significant color error. The technique makes use of a commodity camera and highdynamic range sensing to measure color gamuts at many different spatial locations. A differentiable energy function is defined that combines both a smoothness and data term. This energy function is globally minimized through the successive application of projective warps defined using gradient descent. After convergence the warps can be applied at runtime to minimize color defects in the display. The framework is demonstrated on displays that suffer from several sources of color error.
24

Context-based innovative mobile user interfaces / Interfaces utilisateurs mobiles innovantes basées sur le contexte

Zhou, Yun 08 October 2012 (has links)
Avec le développement de différents capteurs et des dispositifs, l'informatique ne se limite plus à la mode bureautique. Cependant, l'interface utilisateur traditionnelle, utilisée sur l'ordinateur de bureau, n'est plus approprié pour l'informatique ubiquitaire. La complexité de l'environnement mobile demande la conception d'interfaces dédiées impliquant des techniques d'entrée et la sortie qui contiennent les nouvelles caractéristiques émergentes au-delà des techniques traditionnelles. L'une des solutions possibles pour permettre l'interaction omniprésente soit le nomadisme, soit la mobilité. Nous proposons trois interfaces liées à ces deux solutions: L'interface fixé dan l'environnement (abréviation de IEI en anglais), interface dépendante de l'environnement (EDI) et Interface Indépendante de l'environnement (EII). Tout d'abord, nous présentons globalement notre approche sur la conception de ces trois interfaces innovantes (IEI, EDI et EII), leurs configurations portées (dispositif d'affichage portée sur les lunettes plus caméra et dispositif d'affichage pico-projecteur plus caméra), des exemples réels d'utilisation et une évaluation préliminaire des techniques d'entrée de sélection pour prouver la faisabilité de nos prototypes. Par la suite, nous proposons sur les dispositifs portées, et seule les EDI et les EII seraient étudié plus en détail. Afin de concrétiser l'EDI et l'EII, nous proposons un continuum allant de l'interface physique, l'interface mixte physique-numérique, jusqu'à l'interface totalement numérique. Basé sur l'interface physique, nous proposons le système MobilePaperAccess qui sur le dispositif d'affichage portée sur les lunettes plus caméra permettant l'accès à l'information numérique à partir d'une interface imprimé du papier. Ce système est conçu pour valider nos concepts de l'EDI et de l'EII. Les deux types d'interfaces (EDI et EII) et trois techniques d'entrée (doigt, masque et carnet) ont été évaluées par les méthodes quantitatives et qualitatives avec ce système. Basé sur l'interface numérique projetée multi-échelle, le système PlayAllAround est sur dispositif d'affichage pico-projecteur plus caméra, et il pouvoir fournir un affichage à différentes tailles, à la plus petite, individuelle et portée, à la plus grande, partageable et publique. Pour la conception de ce système, nous proposons une décomposition de l'interface basée sur une de cellule de référence de taille fixé pourrait la mise à l'échelle de l'interface en fonctionne de la taille de projection. Le geste de sélection sur un vol et l'interface multi-échelle ont été évalués avec ce système. Les résultats de nos expériences ont montré que PlayAllAround fonctionne bien avec le geste de sélection sur un vol et l'interface multi-échelle. Pour aller plus loin, nous explorons les gestes de la main, y compris le geste stationnaire, le geste de pincement et le geste de fermeture du poing. Nous employons le geste de pincement et le geste de fermeture du poing comme entrée pour pointer, l'action de glisser-déposer et la action de tracer. Afin de satisfaire aux exigences de l'interaction dans la vie quotidienne, nous étudions comment l'utilisateur peut interagir avec ces gestes à l'arrêt ou en marchant. Nous comparons les interactions du geste de sélection sur un vol et geste de pincement dans trois situations que debout, assis et en marchant. En outre, l'évaluation de l'interface projetée, ainsi que la satisfaction sur le fonctionnement de la configuration porté sur la tête a été faite et discutée. Enfin, le long du continuum, nous continuons à étudier sur l'interface mixte par un dispositif pico-projecteur plus caméra dans le but de concrétiser les concepts de l'EDI et de l'EII. L'interface mixte contient une partie physique basée sur des marqueurs d'ARToolkit et une partie numérique projetée. […] / With the development of a wide variety of sensors and devices, computing is no longer limited to the desktop mode. However, the traditional user interface, used on the desktop computer, is no longer appropriate for ubiquitous computing. A sophisticated mobile environment re-quires dedicated design of interfaces, involving input and output techniques with new emerging features that go far beyond the capacities of traditional techniques. One of the solutions to enable ubiquitous interaction and end limitation of the desktop mode is nomadism, while another is mobility. We propose three interfaces related to these two solutions: In-environment interface (IEI), Environment Dependent Interface (EDI), and Environment Independent Interface (EII). We exclude IEI and mainly focus on wear-able interaction. This thesis aims to investigate research issues involved in the design, implementation and evaluation of EDI and EII. It presents our design approach to these three innovative interfaces (IEI, EDI and EII), their wear-able configurations (camera-glasses device unit and cam-era-projector device unit), real examples of use (including the Research Team Interaction Scenario), and both the quantitative and qualitative user studies and evaluations to prove the feasibility and usability of our prototypes. Our work is a many-sided investigation on innovative wearable interfaces, as well as input and output techniques, which will pave the way for future research into wearable interfaces.
25

Kubo–Greenwood electrical conductivity formulation and implementation for projector augmented wave datasets

Calderín, L., Karasiev, V.V., Trickey, S.B. 12 1900 (has links)
As the foundation for a new computational implementation, we survey the calculation of the complex electrical conductivity tensor based on the Kubo-Greenwood (KG) formalism (Kubo, 1957; Greenwood, 1958), with emphasis on derivations and technical aspects pertinent to use of projector augmented wave datasets with plane wave basis sets (BIlichl, 1994). New analytical results and a full implementation of the KG approach in an open-source Fortran 90 post-processing code for use with Quantum Espresso (Giannozzi et al., 2009) are presented. Named KGEC ([K]ubo [G]reenwood [E]lectronic [C]onductivity), the code calculates the full complex conductivity tensor (not just the average trace). It supports use of either the original KG formula or the popular one approximated in terms of a Dirac delta function. It provides both Gaussian and Lorentzian representations of the Dirac delta function (though the Lorentzian is preferable on basic grounds). KGEC provides decomposition of the conductivity into intra- and inter band contributions as well as degenerate state contributions. It calculates the dc conductivity tensor directly. It is MPI parallelized over k-points, bands, and plane waves, with an option to recover the plane wave processes for their use in band parallelization as well. It is designed to provide rapid convergence with respect to k-point density. Examples of its use are given.
26

Možnosti využití moderních technologií ve výuce ekonomických předmětů na SŠ / Possibilities of using modern technologies in teaching economics in secondary schools

Čejková, Lenka January 2015 (has links)
This thesis is thematically focused on the use of modern technology in economic education at secondary schools. The theoretical part discusses the issue of modernization of education, including the presentation of the Ministry of Education document Strategy digital education by 2020. Furthermore in the context of theoretical analyzed in detail the different types of modern technology and the last chapter of this part of this thesis deals with current projects, which are designed to support the modernization of education. In the empirical part of this thesis, analyzes a survey carried out among teachers of business subject at secondary schools and pupils at a secondary school as well. The aim of this section is to use the survey to determine attitudes of teachers and students to modern technologies. And then also examine the possibilities of new modern technologies in teaching business subjects.
27

Deskové hry na interaktivním stole / Board Games on Interactive Table

Svoboda, Petr January 2016 (has links)
This thesis focuses on the application of the tangible user interface and spatial augmented reality principals for playing board games. For this purpose, a system called interactive table was developed. It is both hardware and software solution. The hardware part solves the installation of a depth camera and a projector located above the table. The software solution deals with calibration of the depth camera and projector system using known procedures for camera calibration on the one hand, on the other hand it solves tasks from the field of computer vision. This perceptional part is the core of the whole thesis and for the purposes of playing board games it provides information about the location of the physical game object, physical game board and the calculations of mask for masking distracting objects. An educational application was developed for the purposes of demonstration of the system options. The interactive table offers new possibilities for playing board games in a real-world environment by the combination of the augmented reality elements with real-world objects and the related new user experience.
28

A Structured Light Based 3D Reconstruction Using Combined Circular Phase Shifting Patterns

Zhang, Yujia 11 July 2019 (has links)
No description available.
29

Image Analysis for Compliant Measurements and Calibration of Visual Projector Systems

Westberg, Daniel January 2023 (has links)
A realistic visualization that enhances a virtually authentic experience is the ambition of any visualization system in a simulator environment. But calibrating and maintaining a high quality visualization system entail large costs, resources and time. Hence, a soft- ware has been developed to facilitate the measuring of three useful metrics that lay the foundation for automatic calibration of visual projector systems. The software and associ- ated method conducts relevant measurements which are compatible with arbitrary surface shapes and can be utilized as an assurance of quality measurement tool. The measure- ments include absolute surface shape, absolute geometry and projector blending zone con- tributions. The implementation decrease manual complexity for users, adds environmen- tal flexibility, increase density of measurement points and is more cost and time efficient then existing methods. / <p>Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet</p>
30

Tunable Liquid Crystal Etalon and Photonic Devices

Dorjgotov, Enkh-Amgalan 15 July 2010 (has links)
No description available.

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