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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.
91

Walk-A-Way : A Maya Plug-in for Walk Cycle Automation

Christiansson, Kajsa January 2009 (has links)
<p>In 3D and 2D animations walk cycles of characters appear very frequently and are an important way of expressing various aspects of the story told. However walk cycles are tedious and time consuming to animate. In this work an Autodesk MAYA plug-in has been developed, that aims at automating this process. The walk cycle plug-in can be highly beneficial for animators when creating convincing walk cycles in a fast and simple way. The plug-in calculates the right values for each phase in the walk cycle. The GUI of the plug-in makes it easy to provide the required input parameters. In addition, the plug-in allows the animation of a character to walk along a chosen path.</p>
92

Stereoscopy : Fooling the Brain into Believing There is Depth in a Flat Image

Johansson, Anders January 2009 (has links)
<p>Stereoscopy is a technique that can create an illusion of depth in a flat image. There are many different methods to do this, and here is explained some of the most common and popular ways, with a bigger focus on the anaglyphic method. Since stereoscopy is an old technique, the discovery of it by Charles Wheatstone is explained briefly. In Autodesk Maya 2009, a new stereoscopic plug-in was included which makes the creation of stereoscopic imagery easier. An animated project is made during the course of this research which takes advantage of and tests the functions of the new plug-in. The main purpose of the project is to create a stereoscopic movie which utilized the anaglyph stereoscopic technique. The result is rendered stereoscopic material that is edited with Adobe Premiere Pro to create anaglyphic imagery and a full color alternative using the Infitec technique.</p>
93

Plug-in for stereoscopic studio production using 3Ds Max

Nilsson, Linus January 2010 (has links)
<p>In this day and age when 3D cinema is ever increasing in popularity and 3D television sets on the verge of becoming a reality in our homes, the media production companies are interested in looking at how they can start producing stereoscopic format media for this exciting medium. This thesis proposes a solution to parts of the stereoscopic production pipeline by examining and proposing the extent of the requirements of a plug-in to aid in the setting up and rendering of stereo pairs and ultimately proposing such a plug-in and modifying it to suit the proposed requirements. With a high emphasis on ensuring that the plug-in is capable of producing enjoyable stereoscopic content, the plug-in is tested by rendering a demanding scene previously used in factual production work. The findings of these tests ultimately lead to the evaluation of the plug-ins usefulness as a tool for not only the production studio involved but for anyone interested in generating material for this exciting medium.</p>
94

Konceptframtagning av inspektionspluggar till flygmotorer

Roskvist, Jimmy, Rydell, Richard January 2009 (has links)
<p>This report describes the results of the project "Concept development of jet engine inspection plugs" carried out in the spring of 2008. The work was done at the department of product definition at the company Volvo Aero in Trollhättan. The objective of the work was to develop concepts for a "Volvo-unique" inspection plug. The work is part of Volvo Aero's focus on proprietary (self-developed) technologies. Inspection plugs can be found on virtually all aircraft engines and gas turbines. They are used during inspections with fiber optics done at regular intervals during engine operation. Since the inspection plugs are screwed in and out many times during the life of an engine, it is important that the handling (the assembly and disassembly) is simple. It is also very important that the plugs are properly fixed in position to prevent them from coming off during operation. The focus of the work was to develop proposals on how the assembly and fixing of plugs could be designed to simplify the handling and have adequate and simple function. The procedure during the work was to first study relevant theory and methods that could be used. Then development was carried out according to the first steps of the systematic design methods. These steps include product specifications, concept generation, evaluation and selection of concepts, and development of selected concept. During the implementation, a number of tools and methods, including QFD, FMEA and decision matrices were used. Out of 14 developed concepts, two were chosen for comparison with a leading rival. Both developed concepts turned out to outscore the competitor and the main difference was the cost of production. One of the concepts was considered to have advantages over the other and was consequently chosen for further development. Geometry, manufacturing, materials, sealing and misalignment were the focus areas of the development. CAD models were made of the various design ideas that were identified and one principal inspection plug was recommended for further development.</p>
95

Analysis and LQ-optimal control of infinite-dimensional semilinear systems : application to a plug flow reactor

Aksikas, Ilyasse 07 December 2005 (has links)
Tubular reactors cover a large class of processes in chemical and biochemical engineering. They are typically reactors in which the medium is not homogeneous (like fixed-bed reactors, packed-bed reactors, fluidized-bed reactors,...) and possibly involve diferent phases (liquid/solid/gas). The dynamics of nonisothermal axial dispersion or plug flow tubular reactors are described by semilinear partial differential equations (PDE's) derived from mass and energy balances. The main source of nonlinearities in such dynamics is concentrated in the kinetics terms of the model equations. Like tubular reactors many physical phenomena are modelled by partial differential equations (PDE's). Such systems are called distributed parameter systems. Control problems of these systems can be formulated in state-space form in a way analogous to those of lumped parameter systems (those described by ordinary differential equations) if one introduces a suitable infinite-dimensional state-space and suitable operators instead of the usual matrices. This thesis deals with the synthesis of optimal control laws with a view to regulate the temperature and the reactant concentration of a nonisothermal plug flow reactor model. Several tools of linear and semilinear infinite-dimensional system theory are extended and/or developed, and applied to this model. On the one hand, the concept of asymptotic stability is studied for a class of infinite-dimensional semilinear Banach state- space systems. Asymptotic stability criteria are established, which are based on the concept of strictly m-dissipative operator. This theory is applied to a nonisothermal plug flow reactor. On the other hand, the concept of optimal Linear-Quadratic (LQ) feedback is studied for class of infinite-dimensional linear systems. This theory is applied to a linearized plug flow reactor model in order to design an LQ optimal feedback controller. Then the resulting nonlinear closed-loop system performances are analyzed. Finally this control design strategy is extended to a large class of first-order hyperbolic PDE's systems.
96

A framework for flexible integration in robotics and its applications for calibration and error compensation

To, Minh Hoang 06 1900 (has links)
Robotics has been considered as a viable automation solution for the aerospace industry to address manufacturing cost. Many of the existing robot systems augmented with guidance from a large volume metrology system have proved to meet the high dimensional accuracy requirements in aero-structure assembly. However, they have been mainly deployed as costly and dedicated systems, which might not be ideal for aerospace manufacturing having low production rate and long cycle time. The work described in this thesis is to provide technical solutions to improve the flexibility and cost-efficiency of such metrology-integrated robot systems. To address the flexibility, a software framework that supports reconfigurable system integration is developed. The framework provides a design methodology to compose distributed software components which can be integrated dynamically at runtime. This provides the potential for the automation devices (robots, metrology, actuators etc.) controlled by these software components to be assembled on demand for various assembly applications. To reduce the cost of deployment, this thesis proposes a two-stage error compensation scheme for industrial robots that requires only intermittent metrology input, thus allowing for one expensive metrology system to be used by a number of robots. Robot calibration is employed in the first stage to reduce the majority of robot inaccuracy then the metrology will correct the residual errors. In this work, a new calibration model for serial robots having a parallelogram linkage is developed that takes into account both geometric errors and joint deflections induced by link masses and weight of the end-effectors. Experiments are conducted to evaluate the two pieces of work presented above. The proposed framework is adopted to create a distributed control system that implements calibration and error compensation for a large industrial robot having a parallelogram linkage. The control system is formed by hot-plugging the control applications of the robot and metrology used together. Experimental results show that the developed error model was able to improve the 3 positional accuracy of the loaded robot from several millimetres to less than one millimetre and reduce half of the time previously required to correct the errors by using only the metrology. The experiments also demonstrate the capability of sharing one metrology system to more than one robot.
97

The Practical PEV: Removing Barriers to Plug-In Electric Vehicle Charging and Ownership

Parry, Stephen 01 May 2011 (has links)
The paradigm of personal transportation is changing. Electric vehicles are here. The arrival of the Tesla Roadster, Nissan Leaf, and Chevy Volt has changed the way in which we have to think about the energy that fuels our transportation needs. As PEVs find their way into garages this year and especially in the coming years, the neighborhood, city, state, and regional electric infrastructure will take on a new importance for many people as their interactions with it become significantly more complex and intimate as a result of regular electric vehicle charging.
98

各種自動車の総合評価と持続可能なシステム

Sano, Mitsuru, 佐野, 充 12 1900 (has links)
No description available.
99

Konceptframtagning av inspektionspluggar till flygmotorer

Roskvist, Jimmy, Rydell, Richard January 2009 (has links)
This report describes the results of the project "Concept development of jet engine inspection plugs" carried out in the spring of 2008. The work was done at the department of product definition at the company Volvo Aero in Trollhättan. The objective of the work was to develop concepts for a "Volvo-unique" inspection plug. The work is part of Volvo Aero's focus on proprietary (self-developed) technologies. Inspection plugs can be found on virtually all aircraft engines and gas turbines. They are used during inspections with fiber optics done at regular intervals during engine operation. Since the inspection plugs are screwed in and out many times during the life of an engine, it is important that the handling (the assembly and disassembly) is simple. It is also very important that the plugs are properly fixed in position to prevent them from coming off during operation. The focus of the work was to develop proposals on how the assembly and fixing of plugs could be designed to simplify the handling and have adequate and simple function. The procedure during the work was to first study relevant theory and methods that could be used. Then development was carried out according to the first steps of the systematic design methods. These steps include product specifications, concept generation, evaluation and selection of concepts, and development of selected concept. During the implementation, a number of tools and methods, including QFD, FMEA and decision matrices were used. Out of 14 developed concepts, two were chosen for comparison with a leading rival. Both developed concepts turned out to outscore the competitor and the main difference was the cost of production. One of the concepts was considered to have advantages over the other and was consequently chosen for further development. Geometry, manufacturing, materials, sealing and misalignment were the focus areas of the development. CAD models were made of the various design ideas that were identified and one principal inspection plug was recommended for further development.
100

Optimization of a plug-in hybrid electric vehicle

Golbuff, Sam 22 May 2006 (has links)
A plug-in hybrid electric vehicle (PHEV) is a vehicle powered by a combination of an internal combustion engine and an electric motor with a battery pack. The battery pack can be charged by plugging the vehicle into the electric grid or from using excess engine power. A PHEV allows for all electric operation for limited distances, while having the operation and range of a conventional hybrid electric vehicle on longer trips. A PHEV design with design parameters electric motor size, engine size, battery capacity, and battery chemistry type, is optimized with minimum cost as a figure of merit. The PHEV is required to meet a fixed set of performance constraints consisting of 0-60 mph acceleration, 50-70 mph acceleration, 0-30 mph acceleration in all electric operation, top speed, grade ability, and all electric range. The optimization is carried out for values of all electric range of 10, 20, and 40 miles. The social and economic impacts of the optimum designs in terms of reduced gasoline consumption and carbon emissions reduction are calculated. Argonne National Laboratorys Powertrain Systems Analysis Toolkit is used to simulate the performance and fuel economy of the PHEV designs. The costs of different PHEV components and the present value of battery replacements over the vehicles life are used to determine the designs drivetrain cost. The resulting optimum PHEVs are designs using lead acid battery type. The optimum design parameter values are all determined by a single controlling performance constraint. The PHEV designs show a 63% to 80% reduction in gasoline consumption and a 53% to 47% reduction in CO2 emissions. The PHEV designs have an annual gas savings of $696 to $643 per year over the average sedan meeting the 27.5 mpg CAFE standards.

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