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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.
11

KONSTRUKTION AV FÄSTE TILL FÖNSTERLUCKA : Design of shutter attachment

Walfridsson, Rickard January 2008 (has links)
The task given by Balco AB was to redesign the productsystem ”vikglas utan ram” and to make the shutter able to go pass a corner. Today the shutter can only be moved sideways. A prototype to test the shutter concept will be made. The final product will be used in Balco AB:s existing product family as a new product or as a choice. The shutter solution shall give a feeling of quality and easiness to fit in. A few of the demands to achieve this goal is by using special made shutter attachments and the use of bearings. The new shutter attachment has to be safe, reliable and have a low noise level. / Uppgiften som beställdes av Balco AB gick ut på att omkonstruera deras ”vikglas utan ram” system för att få fönsterluckan att gå förbi ett balkonghörn. Idag kan luckan endast föras i sidled. En prototyp avsedd för att testa ut lucka förbi hörn konceptet skall utvecklas. Slutprodukten skall användas i Balco AB:s befintliga produktsortiment som en ny produkt eller som ett tillval. Lucklösningen skall inge en viss känsla av kvalité och smidighet för att passa in. Några av kraven som ställs för att uppnå denna känsla är bland annat specialdesignade infästen till luckan samt nyttjande av kullager. Den nya inästningsanordningen skall även vara säker och pålitlig samt ha en tyst arbetsgång.
12

3D mapping with iPhone / 3D-kartering med iPhone

Lundqvist, Tobias January 2011 (has links)
Today, 3D models of cities are created from aerial images using a camera rig. Images, together with sensor data from the flights, are stored for further processing when building 3D models. However, there is a market demand for a more mobile solution of satisfactory quality. If the camera position can be calculated for each image, there is an existing algorithm available for the creation of 3D models. This master thesis project aims to investigate whether the iPhone 4 offers good enough image and sensor data quality from which 3D models can be created. Calculations on movements and rotations from sensor data forms the foundation of the image processing, and should refine the camera position estimations. The 3D models are built only from image processing since sensor data cannot be used due to poor data accuracy. Because of that, the scaling of the 3D models are unknown and a measurement is needed on the real objects to make scaling possible. Compared to a test algorithm that calculates 3D models from only images, already available at the SBD’s system, the quality of the 3D model in this master thesis project is almost the same or, in some respects, even better when compared with the human eye.
13

Implementation of an Active Pixel Sensor with Shutter and Analog Summing in a 0.35um Process / Implementation av en ljussensor med aktiva pixlar, elektronisk slutare och analogsummering i en 0.35um process.

Johansson, Robert January 2003 (has links)
An integrated circuit for evaluation of APS technology has been implemented in a 0.35 um process. The APS features snapshot operation and the readout circuitry can carry out: CDS, DS, and analog summing all in one circuit that is fully programmable. The output from the chip is a differential analog signal, intended to be connected to a high-speed ADC on an evaluation board. The sensor is fully compatible with current IVP camera systems, hence, the evaluation board should be easy to design. Several small code snippets that illustrate different modes of readout have been outlined, to aid the evaluation of the chip. It should be fairly straightforward to convert these code snippetsinto actual camera code. Furthermore, some code to illustrate a possible application and a faster mode of CDS have been indicated. Six types of APs have been implemented. They differ regarding diode type and implementation of the sampling capacitor. Design instructions and models for hand calculation have been described. The models have in most cases been validated by simulations and it has been shown that a readout speed of 8 MHz is possible to obtain, even for a larger sensor than this test chip. The desired resolution of 8 bits cannot be obtained for high levels of illumination. However, for low levels of illumination a resolution as high as 10 bits is possible. The chip layout has been validated to a large extent and should result in a fully functional chip, if manufactured. However, in the eventuality that IVP decides to manufacture this chip it is recommended to use the newer CAD tools, not available to the author at the time of implementation, to check the chip design for DRC and LVS errors.
14

VO2 films as active infrared shutters

Johansson, Daniel January 2006 (has links)
An active optical shutter for infrared light (3-5 μm) has been designed, exploiting the phase transition in thermochromic vanadium dioxide (VO2). A spin coating processing route for VO2 films has been adapted to manufacture reproducible depositions onto sapphire (Al2O3) substrates. The VO2 films have been characterized by X-ray powder diffraction (XRPD) and infrared spectroscopy (FTIR), showing 55 % transmittance in the open mode and 0.1 % in the closed mode. The VO2 film temperature determines the operating mode of the shutter, and a resistive circuit of gold was deposited on top of the film for heating purposes. Switching times from the open to the closed mode down to 15 ms have been measured. This work is a part of a comprehensive project at the Swedish Defence Research Agency (FOI), aiming to improve active components for protection against lasers. The shutter within this work is at this stage an early prototype, and needs further development and complementary systems such as a control unit to be implemented in an optical system.
15

Characterization and growth of InGaN on ZnO(0001) substrate by Plasma-Assisted Molecular Beam Epitaxy

Yang, Chen-chi 12 July 2011 (has links)
This article describes that we grew InGaN ternary films by Plasma- Assisted Molecular Beam Epitaxy (PAMBE) on the ZnO substrate O-polar (0001) surface. Before we grew the films, we grew the InN films on the ZnO substrate to find out the interface reaction conditions. We used Double Crystal X-ray Diffraction (XRD) to analyze the diffraction peak of InGaN films after we grew them. We found it was very hard to grow the single content InGaN films by generally methods. We tried period shutter control method to grow films, and we succeeded to grow the single phase films. We analyzed the morphologies by AFM and SEM, the microstructures by TEM, the electric properties by Hall measurement, and the fluorescent characteristics by PL.
16

KONSTRUKTION AV FÄSTE TILL FÖNSTERLUCKA : Design of shutter attachment

Walfridsson, Rickard January 2008 (has links)
<p>The task given by Balco AB was to redesign the productsystem ”vikglas utan ram” and to make the shutter able to go pass a corner. Today the shutter can only be moved sideways. A prototype to test the shutter concept will be made. The final product will be used in Balco AB:s existing product family as a new product or as a choice. The shutter solution shall give a feeling of quality and easiness to fit in.</p><p>A few of the demands to achieve this goal is by using special made shutter attachments and the use of bearings. The new shutter attachment has to be safe, reliable and have a low noise level.</p> / <p>Uppgiften som beställdes av Balco AB gick ut på att omkonstruera deras ”vikglas utan ram” system för att få fönsterluckan att gå förbi ett balkonghörn. Idag kan luckan endast föras i sidled. En prototyp avsedd för att testa ut lucka förbi hörn konceptet skall utvecklas. Slutprodukten skall användas i Balco AB:s befintliga produktsortiment som en ny produkt eller som ett tillval. Lucklösningen skall inge en viss känsla av kvalité och smidighet för att passa in.</p><p>Några av kraven som ställs för att uppnå denna känsla är bland annat specialdesignade infästen till luckan samt nyttjande av kullager. Den nya inästningsanordningen skall även vara säker och pålitlig samt ha en tyst arbetsgång.</p>
17

Video stabilization and rectification for handheld cameras

Jia, Chao 26 June 2014 (has links)
Video data has increased dramatically in recent years due to the prevalence of handheld cameras. Such videos, however, are usually shakier compared to videos shot by tripod-mounted cameras or cameras with mechanical stabilizers. In addition, most handheld cameras use CMOS sensors. In a CMOS sensor camera, different rows in a frame are read/reset sequentially from top to bottom. When there is fast relative motion between the scene and the video camera, a frame can be distorted because each row was captured under a different 3D-to-2D projection. This kind of distortion is known as rolling shutter effect. Digital video stabilization and rolling shutter rectification seek to remove the unwanted frame-to-frame jitter and rolling shutter effect, in order to generate visually stable and pleasant videos. In general, we need to (1) estimate the camera motion, (2) regenerate camera motion, and (3) synthesize new frames. This dissertation aims at improving the first two steps of video stabilization and rolling shutter rectification. It has been shown that the inertial sensors in handheld devices can provide more accurate and robust motion estimation compared to vision-based methods. This dissertation proposes an online camera-gyroscope calibration method for sensor fusion while a user is capturing video. The proposed method uses an implicit extended Kalman filter and is based on multiple-view geometry in a rolling shutter camera model. It is able to estimate the needed calibration parameters online with all kinds of camera motion. Given the camera motion estimated from inertial sensors after the pro- posed calibration method, this dissertation first proposes an offline motion smoothing algorithm based on a 3D rotational camera motion model. The offline motion smoothing is formulated as a geodesic-convex regression problem on the manifold of rotation matrix sequences. The formulated problem is solved by an efficient two-metric projection algorithm on the manifold. The geodesic-distance-based smoothness metric better exploits the manifold structure of sequences of rotation matrices. Then this dissertation proposes two online motion smoothing algorithms that are also based on a 3D rotational camera motion model. The first algorithm extends IIR filtering from Euclidean space to the nonlinear manifold of 3D rotation matrices. The second algorithm uses unscented Kalman filtering on a constant angular velocity model. Both offline and online motion smoothing algorithms are constrained to guarantee that no black borders intrude into the stabilized frames. / text
18

Broms- och styrsystem för möbeljalusier

Swalbring, Johan January 2007 (has links)
This report is the result of a master thesis at the Department of Mechanical Engineering, Division of Industrial and Economical Development, at Linköping University of Technology. The project was carried out on behalf of Fanerami AB, Mjölby and includes 20 weeks of full time schedule work. Cabinets with vertical mounted roller shutters all share the same problem, namely weight balancing. A roller shutter has an equilibrium area where the sum of the different forces acting on the shutter equals zero. As the shutter leaves that area it will pick up speed as it falls towards the bottom. When the shutter hits the bottom of the cabinet there is a potential risk of getting fingers caught and in this project a solution to prevent this from happening was to be presented. In this project, three concepts have been generated with the following different purposes: •In concept 1 the risk of getting any fingers caught when the shutter closes was to be eliminated in an efficient and inexpensive way. •In concept 2 the roller shutter had to be balanced at all time providing the possibility to keep the cabinet open in any position. •The last and most challenging task was to create a remote controlled TV cabinet. The shutters were mounted horizontally and were to be opened simply by pushing the bottom either on the remote transmitter unit or the cabinet. The first concept uses a small oil damper, often seen in kitchen cabinets and drawers. The roller shutter applies pressure on the damper via a lever that transforms the shutter motion along a certain path to a smaller motion in the direction of the damper. By doing so, a smaller damper with higher pressure can be used. Dampers are available with several different pressures and can be mounted in five different positions; therefore the concept can be adjusted to fit almost any cabinet. Concept 2 consists of a thin cord winded around a wheel. The wheel is equipped with a spring that tightens when the cord is pulled in. The spring produces an equal and opposite force that holds the shutter in balance. As the wheel is mounted in the upper front of the cabinet, underneath the shutter, it will almost be invisible. The concept is easy to adjust to most cabinets by simply attach the shutter at different levels. In that way the spring will be tightened to equal the weight of the shutter. The design of the TV cabinet has been a working progress throughout the whole project. A couple of prototypes were produced before the final concept. The mechanical solution is based on two pinion rackets placed one on each side of a rotating pinion powered by a motor through a planetary gearbox. To control the cabinet Electronic Solutions AB developed an electronic system that made it possible to open and close the shutters with a remote control or a switch on the cabinet.
19

Visual Sampling with the EEG Alpha Oscillation

Alexander, Kevin Eugene 13 August 2020 (has links)
No description available.
20

Liquid Crystal Polarization Volume Hologram for Augmented Reality Applications

Feng, Xiayu 29 April 2021 (has links)
No description available.

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