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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.
181

Inkludering - för vem? : Inkludering i klassrum och fritidshem sett utifrån tre olika perspektiv

Östling, Henrik January 2016 (has links)
In this essay I have examined the inclusion in the school, specifically in the classroom and leisure time center. Inclusion means briefly that all students, regardless of their capability for school work, should be part of the planned teaching, and also be able to assimilate the knowledge that is intended to be conveyed. During my years as an educator in classroom and after-school center I've seen how this inclusion is very complicated to implement and sometimes impracticable. I have investigated how inclusion works and how it does not work in both the classroom and in the leisure time center. I have done this by examining the inclusion from three different perspectives: student´s, educator´s and school´s. I show and discuss how different inclusion can be perceived depending on which perspective you look from. I also describe how inclusion is shaped, both positively and negatively, by external factors, so-called framework factors. I discuss how these framework factors provide or do not provide educational opportunities and how they condition the educator´s practice. Opportunities that sometimes are taken advantage of and sometimes overlooked.
182

UTTR BEST TELEMETRY SOURCE SELECTOR

Rigley, Kenneth H., Wheelwright, David H., Fowers, Brandt H. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / The UTTR (Utah Test & Training Range) offers the largest over land test and training airspace in the continental United States. It provides excellent telemetry data processing capability through a number of TM (telemetry) sites. Selecting the best source of telemetry data for optimum coverage from these many sites can be very involved and challenging for ground station personnel. Computer-based best source selection automates this process, thereby increasing accuracy and efficiency. This paper discusses the capabilities of the BTSS (Best Telemetry Source Selector), its background, design and development, applications, and future at the UTTR.
183

The outcome of relapsed and residual clubfeet treated with the Taylor Spatial Frame

Botha, Adriaan Hendrik, Du Toit, Jacques, Lamberts, Robert P. 12 1900 (has links)
Thesis (MMed)--Stellenbosch University, 2014. / No abstract available
184

Stiffness and fatigue behavior of cross frames for steel bridge applications

Battistini, Anthony David 06 November 2014 (has links)
Cross frames are critical for the stability of straight and curved steel bridges. Conventional cross frames are often fabricated from steel angles which are welded to gusset plates through one leg only. Due to this eccentric connection, these angles have substantial bending at the connection that can reduce the member stiffness and can potentially decrease fatigue performance. Because of the low buckling strength, cross frames with angle diagonals are often designed as tension-only systems, therefore increasing the necessary steel to be an effective brace. Improved behavior may result if concentric members are utilized. The increased buckling strength of tubes and double angles results in effective members in both compression and tension, and a single diagonal cross frame can provide effective bracing; however, a suitable connection must be developed. Tubes are often connected by slotting the tube in the center and welding to a gusset plate, which requires precise fabrication. Two proposed solutions that would connect easily to the ends of the member and seal the end of the tube include a steel casting and a T-stem connection. The dissertation studies the development of a steel casting for use in cross frame design and evaluates the performance of the various details described herein in regards to stiffness, strength, and fatigue. Additionally, the dissertation covers the behavior of single angle X and K frame configurations. To date, the determination of the single angle fatigue detail has been largely based on component tests only. The project incorporated full-scale cross frame fatigue tests to fully examine the interaction of the cross frame members with the overall structure. Results from currently used details and proposed connections provide insight to the live load behavior of these braces and multiple recommendations are made to improve the fatigue life. The project examined the stiffness behavior of current and proposed cross frame layouts with large-scale laboratory tests and computational modeling. From these results, a case study compares the fatigue analysis of a commercial structural software package to the stress ranges obtained in a three-dimensional finite element model. Suggestions on how to properly model the cross frames are given. / text
185

Use of Cast Modular Components for Concentrically Braced Steel Frames

Federico, Giovanni January 2012 (has links)
Cast modular components have been under development for earthquake resistant steel structures. These concepts take advantage of the versatility in geometry afforded with the casting process to create components specifically configured for ductile behavior. Two systems were developed as part of this dissertation research: (1) the Cast Modular Ductile Bracing system (CMDB); (2) the Floating Brace system (FB).The CMDB system makes use of cast components introduced at the ends and the center of the brace to produce a special bracing detail with reliable strength, stiffness and deformation capacity. The system takes advantage of the versatility in geometry offered by the casting process to create configurations that eliminate non-ductile failure modes in favor of stable inelastic deformation capacity. This thesis presents analytical research performed to determine the buckling strength and buckling direction of the bracing element based on the geometries of the cast components. Limiting geometries are determined for the cast components to control the buckling direction. Design formulas for buckling strength are proposed. The Floating Brace system is a new lateral bracing concept developed for steel special concentric braced frames. The concept uses a set of special plate details at the end of the brace to create a stiff, strong and ductile lateral bracing system. The plates are arranged such that some provide direct axial support for high initial stiffness and elimination of fatigue issues for daily service wind loads. The remaining plates are oriented transverse to the brace and thus provide ductile bending response for the rare earthquake event, in which the axial plates become sacrificial. The main bracing member and cast pieces remain elastic or nearly elastic. Thus, following the seismic event, the plates can be replaced. In this thesis, analytical studies using nonlinear finite element analysis are performed to determine the optimum: (a) relative strength of the end connection to the brace; and (b) ratio of strength between axial and transverse plates. Design equations are provided. Prototypes for each concept were developed. Castings were created. Large scale laboratory physical testing was performed as experimental verification (proof of concept) for the two systems.
186

Fire resistance of earthquake damaged reinforced concrete frames

Ab. Kadir, Mariyana Aida January 2013 (has links)
The topic of structural damage caused by fires following an earthquake (FFE) has been discussed extensively by many researchers for over a decade in order to bring the two fields closer together in the context of performance based structural engineering. Edinburgh University, Heriot-Watt University, Indian Institute of Technology Roorkee (IIT Roorkee) and Indian Institute of Science initiated a collaboration to study this problem under a UK-India Engineering Research Initiative (UKIERI) funded project. The first construction of a single-storey reinforced concrete frame at IIT Roorkee was completed in summer 2011; this is known as the Roorkee Frame Test 1 throughout this thesis. This thesis presents the modelling of the Roorkee Frame Test 1 using the finite element method and assesses the capability of the numerical methodologies for analysing these two sequential events. Both two and three dimensional finite element models were developed. Beam and shell elements were chosen for the numerical modelling, which was carried out using the general purpose finite element package ABAQUS (version 6.8). The variation in material properties caused by these two types of loading, including strength and stiffness degradation, compressive hardening, tension stiffening, and thermal properties, is implemented in the numerical modelling. Constitutive material calculations are in accordance with EC4 Part 1.1, and all loading is according to IS 1893:2002 Part 1 (Indian Standard). The time-temperature curve used in the analysis is based on data from the test carried out. The behaviour of the Roorkee Frame Test 1 when subjected to monotonic, cyclic lateral loading followed by fire is presented. The capacity of the frame when subjected to lateral loading is examined using a static non-linear pushover method. Incremental lateral loading is applied in a displacement-controlled manner to induce simulated seismic damage in the frame. The capacity curve, hysteresis loops and residual displacements are presented, discussed and compared with the test results. The heat transfer analysis using three dimensional solid elements was also compared against temperature distributions recorded during the Roorkee frame fire test. Based on the smoke layer theory, two emissivity values were defined. In this study, the suitability of numerical modelling using ABAQUS to capture the behaviour of Roorkee frame test is examined. The results from this study show that the 3D ABAQUS model predicted more reliable hysteresis curves compared to the 2D ABAQUS model, but both models estimated the lateral load capacity well. However neither model was able to simulate the pinching effect clearly visible in the hysteresis curves from the test. This was due to noninclusion of the bond slip effect between reinforcing bars and concrete. The residual displacement obtained at the end of the cyclic lateral loading analysis from the 2D ABAQUS model is higher than that seen in the test. However, the result in the 3D ABAQUS model matched the trend obtained in the test. The both columns appear to stiffen under the heating and the residual displacement seems to recover slightly. Lateral displacements, obtained in the thermo-mechanical analysis of the numerical models, show that thermal expansion brings the frame back towards its initial position. Finally, correlation studies between analytical and experimental results are conducted with the objective to establish the validity of the proposed model and identify the significance of various effects on the local and global response of fire resistance earthquake damaged of reinforced concrete frames. These studies show that the effect of tension stiffening and bond-slip are very important and should always be included in finite element models of the response of reinforced concrete frame with the smeared crack model when subjected to lateral and thermal loading. The behaviour of reinforced concrete frames exposed to fire is usually described in terms of the concept of the fire resistance which defined in terms of displacement limit. This study shows the global displacement of the frame subjected to fire recover slightly due to the thermal expansion during the heating.
187

Shrinking the Cost of Telemetry Frame Synchronization

Ghuman, Parminder, Bennett, Toby, Solomon, Jeff 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / To support initiatives for cheaper, faster, better ground telemetry systems, the Data Systems Technology Division (DSTD) at NASA Goddard Space Flight Center is developing a new Very Large Scale Integration (VLSI) Application Specific Integrated Circuit (ASIC) targeted to dramatically lower the cost of telemetry frame synchronization. This single VLSI device, known as the Parallel Integrated Frame Synchronizer (PIFS) chip, integrates most of the functionality contained in high density 9U VME card frame synchronizer subsystems currently in use. In 1987, a first generation 20 Mbps VMEBus frame synchronizer based on 2.0 micron CMOS VLSI technology was developed by Data Systems Technology Division. In 1990, this subsystem architecture was recast using 0.8 micron ECL & GaAs VLSI to achieve 300 Mbps performance. The PIFS chip, based on 0.7 micron CMOS technology, will provide a superset of the current VMEBus subsystem functions at rates up to 500 Mbps at approximately one-tenth current replication costs. Functions performed by this third generation device include true and inverted 64 bit marker correlation with programmable error tolerances, programmable frame length and marker patterns, programmable search-check-lock-flywheel acquisition strategy, slip detection, and CRC error detection. Acquired frames can optionally be annotated with quality trailer and time stamp. A comprehensive set of cumulative accounting registers are provided on-chip for data quality monitoring. Prototypes of the PIFS chip are expected in October 1995. This paper will describe the architecture and implementation of this new low-cost high functionality device.
188

Please, Read the Comments: Exploring the Racial Dialectic of Online Racial Discourse

Ukpabi, Ifeanyichukwu U 15 December 2016 (has links)
More people than ever before are living significant portions of their social lives online due to advancements in internet technology. Over the last few years, we have begun to see the most public discussions of racism increasingly occur online, to be later embedded in the public’s consciousness. It is therefore important for race critical scholars to observe how digital spaces affect racial discourse in the United States. Utilizing a race critical perspective, I explore comment section reactions to counter-framing articles to examine contemporary racial discourse. Through a discourse analysis, I find that counter-framing articles initiate the racial dialectic by inviting white racial frames, thereby structuring contemporary racial discourse. My research suggests race critical scholars should explore the internet as a racialized institution and a site of racial contestation. Race critical theorist must begin to grapple with how such a racialized institution will alter the experiences of racism in social life.
189

Assessing the Roof Structure of the Breeding Barn Using Truss Member Resonant Frequencies

Maille, Nathan James 17 June 2008 (has links)
The motivation for this research was to apply methods of vibrations testing in order to determine axial loads in the pin-ended truss members of the Breeding Bam. This method of vibrations testing was necessary in order to determine the in-situ axial loads of the truss members in the bam. Other common methods, such as strain gauges, were not useful for this application. This is because strain gauges can only detect changes in strain and therefore only changes in load. However due to the size and weight of the roof at the Breeding Bam, significant axial loads are produced in the truss members. This in-situ axial load due to the dead load of the roof is a significant portion of any additional loading and cannot be ignored. The ultimate goal of determining the axial loads in the truss members was to develop a model for the roof structure of the bam that accurately predicts axial loads in the truss members over a range of loading conditions. Developing such a model was important in order to make a structural assessment ofthe Breeding Bam's roof structure. In order to determine the axial loads in the truss members, acceleration time histories of the individual truss members were collected using wireless accelerometers provided by MicroStrain of Williston, Vermont. Using the Fourier transform, power spectral densities were produced from the raw acceleration time histories. It was from these plots that the resonant frequencies of the truss members were determined. Knowing the resonant frequencies for a member and the beam vibration equation developed for pin-ended members, the axial load of the truss member were calculated. This process was done for each wrought iron truss member for three separate loading conditions. The purpose of this was to provide enough experimental data so that it could be compared with predictions of several proposed frame models of the bam's roof structure. Ultimately a model was chosen that best predicted the axial loads in the truss members based upon the three loading combinations tested. Using this frame model, an assessment of the bam's roof structure could be made.
190

Frames for Hilbert spaces and an application to signal processing

Thompson, Kinney 02 May 2012 (has links)
The goal of this paper will be to study how frame theory is applied within the field of signal processing. A frame is a redundant (i.e. not linearly independent) coordinate system for a vector space that satisfies a certain Parseval-type norm inequality. Frames provide a means for transmitting data and, when a certain about of loss is anticipated, their redundancy allows for better signal reconstruction. We will start with the basics of frame theory, give examples of frames and an application that illustrates how this redundancy can be exploited to achieve better signal reconstruction. We also include an introduction to the theory of frames in infinite dimensional Hilbert spaces as well as an interesting example.

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