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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.
1

Programming Code-Modulator and Demodulation-Decoder Suited to PCM Systems

Daqing, Huang 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1989 / Town & Country Hotel & Convention Center, San Diego, California / In order to suit the development of computer telemetry systems, we have developed the intelligent code-modulator and demodulation-decoder. In hardware, they consist of a monolithic processor and some high-integrated devices. Different code or decode ways and several subcarrier modulation or demodulation systems can be varied by carrying out corresponding software programs. In this paper, the equipments' hardware constructions and software cnarts and their main principles are presented.
2

Monolithic 3D integration of asynchronous systems

Lohith, Penmetsa Neela 12 January 2015 (has links)
The goal of this thesis is to study the impact of 3D integration on asynchronous circuits and explore the benefits in power, performance and area compared to traditional two dimensional integration. To enable this study we develop a fully automated asynchronous design methodology and 3D integration flows for asynchronous circuits. This study is also a first one to explore the mutual benefits of asynchronous circuits and 3D integration.
3

Subsídios para projeto e execução de revestimentos em granilite / Contribution for the design and execution of terrazzo flooring

Francelino, Patrícia Rocha de Oliveira 25 April 2012 (has links)
Esta dissertação apresenta um estudo sobre os revestimentos em granilite levando-se em consideração as características do material, de seus materiais constituintes e os processos de produção e execução desse revestimento. Ressalta patologias recorrentes nesse tipo de revestimento, em especial fissurações e desplacamentos. Para estudar a problemática da fissuração e encontrar uma alternativa para que não ocorra, foram produzidos três modelos em granilite com características distintas, que visaram avaliar o comportamento de granilites com e sem solidarização. Para o estudo do sistema solidarizado foram executados: um quadro de 16 \'M POT.2\' e quatro quadros de 2,25 \'M POT.2\' moldados sobre argamassa comumente utilizada como regularização de revestimentos. Para a dessolidarização foi utilizada argamassa mista de cimento e cal com baixo módulo de elasticidade e baixa resistência mecânica, servindo como camada de regularização. Os quadros solidarizados apresentaram fissuras de maneira generalizada e demonstraram que os granilites em sistemas solidarizados fissuram com a fissuração do material a ele monolitizado. Para o quadro dessolidarizado, de 16 \'M POT.2\', o sistema se mostrou eficaz para a não ocorrência de fissuras, apresentando resultados positivos. / This dissertation presents the terrazzo flooring considering the characteristics of the material, constituent materials and the process of production and execution of this covering. Emphasize the recurring pathologies of this type of covering, especially cracking and caused by deficient adherence at the interface zone. To study the problem of cracking and find an alternative that does not occur, it was produced three models in terrazzo with distinct characteristics, that aimed to evaluate the behavior of solidarized and dessolidarized terrazzo. For the study of this monolithic system it was executed: a board of 16 \'M POT.2\' and four boards of 2,25 \'M POT.2\' casted over a mortar commonly used as covering regularization. These boards presented cracks in a generalized way and showed that terrazzo in the monolithic systems open cracks with the material that is monolithically attached to them. For the non-monolithic board, of 16 \'M POT.2\', the system was effective for the absence of cracks, showing positive results. For the non-monolithic system it was used a mixed mortar of cement and lime with low elasticity modulus and low mechanical resistance, serving as a layer of regulation.
4

Subsídios para projeto e execução de revestimentos em granilite / Contribution for the design and execution of terrazzo flooring

Patrícia Rocha de Oliveira Francelino 25 April 2012 (has links)
Esta dissertação apresenta um estudo sobre os revestimentos em granilite levando-se em consideração as características do material, de seus materiais constituintes e os processos de produção e execução desse revestimento. Ressalta patologias recorrentes nesse tipo de revestimento, em especial fissurações e desplacamentos. Para estudar a problemática da fissuração e encontrar uma alternativa para que não ocorra, foram produzidos três modelos em granilite com características distintas, que visaram avaliar o comportamento de granilites com e sem solidarização. Para o estudo do sistema solidarizado foram executados: um quadro de 16 \'M POT.2\' e quatro quadros de 2,25 \'M POT.2\' moldados sobre argamassa comumente utilizada como regularização de revestimentos. Para a dessolidarização foi utilizada argamassa mista de cimento e cal com baixo módulo de elasticidade e baixa resistência mecânica, servindo como camada de regularização. Os quadros solidarizados apresentaram fissuras de maneira generalizada e demonstraram que os granilites em sistemas solidarizados fissuram com a fissuração do material a ele monolitizado. Para o quadro dessolidarizado, de 16 \'M POT.2\', o sistema se mostrou eficaz para a não ocorrência de fissuras, apresentando resultados positivos. / This dissertation presents the terrazzo flooring considering the characteristics of the material, constituent materials and the process of production and execution of this covering. Emphasize the recurring pathologies of this type of covering, especially cracking and caused by deficient adherence at the interface zone. To study the problem of cracking and find an alternative that does not occur, it was produced three models in terrazzo with distinct characteristics, that aimed to evaluate the behavior of solidarized and dessolidarized terrazzo. For the study of this monolithic system it was executed: a board of 16 \'M POT.2\' and four boards of 2,25 \'M POT.2\' casted over a mortar commonly used as covering regularization. These boards presented cracks in a generalized way and showed that terrazzo in the monolithic systems open cracks with the material that is monolithically attached to them. For the non-monolithic board, of 16 \'M POT.2\', the system was effective for the absence of cracks, showing positive results. For the non-monolithic system it was used a mixed mortar of cement and lime with low elasticity modulus and low mechanical resistance, serving as a layer of regulation.
5

Artifical intelligence applied to MMIC layout

Robinson, Jayne Helen January 1995 (has links)
No description available.
6

Influence of coloring techniques and cement opacity on the optical properties of high translucent monolithic zirconia

Yang, Chao-Chieh January 2017 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Background: With the improvement of CAD/CAM technology and translucency of zirconia material, the full contour zirconia crown was introduced to offer dentists a metal free, high strength, and acceptable esthetic prosthesis option. In addition, it is claimed that it is possible to make a full contour high translucent zirconia crown close to natural tooth color by using coloring liquid. However, there is little information in the literature regarding the effect of coloring techniques and cement color on the optical properties of high translucent zirconia. Objective :1) To evaluate the effect of the coloring liquid technique on the resulting optical properties of a monolithic high translucent zirconia 2) To evaluate the cumulative effect of the cement color on the resulting optical properties of a monolithic high translucent zirconia. Alternative hypothesis: There is a significant difference in optical properties between the high translucent monolithic zirconia ceramics with different color staining technique. In addition, the use of shaded resin cement has an effect on the final optical properties of high translucent monolithic zirconia ceramics. Materials and methods: 35 specimens of high translucent zirconia (11mm x11mm) with thickness 1mm was divided into 5 groups according coloring technique, as follows: no color, submerge, two layers of painting, four layers of painting, and six layers of painting. All specimens were measured for the Δ E, transparent parameter (TP), and opalescence parameter(OP) by spectrophotometer (CM-2600D) after firing. Forty-two specimens of high translucent zirconia (11mm x11mm) with thickness 1mm were divided into three groups according to cement color, as follows: clear, opaque, and A2. After firing and cementing with ND4 resin Block. The Δ E, TP and OP will be measured by spectrophotometer. Statistics: The data were analyzed with significant level set at 0.05 one way ANOVA followed by pair-wise group comparisons using Fisher’s Protected Least Significant Differences. Result: 1) The shade of cement significantly affected the mean value of ΔE of E-max CAD and BruxZir high translucent zirconia restoration. Using opaque cement combined with E-max CAD resulted in color difference that was above the clinically perceptible level (ΔE> 3.7). 2) With more layers of staining liquid application, the ΔE and value decreased. The six-layered group showed lowest mean delta ΔE value of 22 (0.78). ΔE was significantly different among groups (p<0.0001). The submerged group showed higher ΔE than the all painting groups. Conclusions: Based on the results of the study, the colors of BruxZir high translucent zirconia and E-max CAD restorations were affected by the shade of cement, whereas white opaque resin cement resulted in BruxZir high translucent zirconia more yellowish. The results of the study demonstrated that the staining technique has an influence on value and final color of Lava-Plus high translucent. Therefore, it is recommended to consider staining technique as one of the influential factors on the final color of zirconia crowns.
7

A Load-to-Fracture and Strain Analysis of Monolithic Zirconia Cantilevered Frameworks

Alshahrani, Faris 28 December 2016 (has links)
No description available.
8

The effect of microscopic residual stress on the deformation of polycrystals

James, Karen Elizabeth January 2001 (has links)
No description available.
9

Monolithic frequency filter designs based on a sampled-data analogue wave filter approach

Reekie, Henry M. January 1981 (has links)
Frequency filters are widely used in communications systems today. Historically they have been constructed from inductors, capacitors and resistors and such circuits are well understood. However they suffer from the disadvantages of large physical size and high cost. A monolithic realisation of frequency filters would greatly reduce the cost of systems in which filters are used and would increase their reliability in hostile environments. In this thesis a novel approach to the realisation of sampled-data monolithic frequency filters is presented. The method is based on the use of sampled analogue signals and is related to the wave digital filter in its design techniques. The eventual monolithic realisation in NMOS technology is in the form of a switched-capacitor structure. While the main body of the research is concerned with the implementation of filters which are based on distributed prototype networks, some work on integratable filters which are based on lumped element prototypes is also presented. For either type the design model is exact and the resulting filter is optimally insensitive to parameter variations. The filters are implemented using a technique which ensures that performance is limited by capacitor ratios, which are moderate as compared with alternative published approaches. A prototype integrated circuit suitable for use in the audio frequency band has been designed to demonstrate the validity of the approach for the filters based on distributed prototypes and contains. filters of third, fifth and seventh order. Results are presented for these filters and also for a pseudobandpass filter which uses the periodicity of the prototype distributed network. The seventh order filter had a cut-off frequency of one eighth of the filter sample rate and achieved a stop band attenuation of well over 70dB An implemetation of a wave filter based on a lumped element prototype is also described and results are presented. This work is expected to form the basis of a novel implemetation of bandpass filters. The responses achieved for all the wave filters constructed show excellent agreement with the theory.
10

Effect of glazes on mechanical and physical properties of various full contour zirconia materials subjected to low temperature degradation

Suleiman, Muad Mohamed A. 11 August 2022 (has links)
OBJECTIVES: To evaluate different surface treatment effects on physical and mechanical properties of various types of zirconia subjected to hydrothermal aging. MATERIALS AND METHODS: This is an in vitro study on four different types of monolithic zirconia material: VITA-Zahnfabrik VITA-YZ T, VITA-YZ HT, VITA-YZ ST, VITA-YZ XT. A total of 240-disc specimens were prepared by core-drilling and sectioned with a diamond blade. Specimens were sintered according to the manufacturer’s recommendations. Half of the specimens in each group were then glazed and subjected to low temperature degradation. Three different locations were evaluated for surface roughness each group of the four different materials by using Mitutoyo SJ-201 contact profilometer with a 5μm diamond stylus tip. A Bruker D2 Phaser diffractometer was used for X-ray diffraction (XRD) measurements. Crystallographic phase identification and analysis were performed through Rietveld refinements on XRD raw data. Biaxial flexural strength was determined and the fractography was analyzed. Descriptive data such as surface roughness, crystallographic phase contents, and flexural strength were indicated as mean and standard deviation (SD). Statistical analysis was performed using multi-way ANOVA and linear regression model followed by the post hoc Tukey tests. RESULTS: All VITA YZ zirconia non-glazed control specimens showed higher means of biaxial flexural strength values compared to glazed specimens. VITA YZ HT specimens showed the highest mean of biaxial flexural strength in this study with values of 781 – 1305 MPa. On the other hand, VITA YZ XT expressed the lowest mean of biaxial flexural strength values of 466 – 972 MPa. The surface roughness of monolithic VITA YZ materials was statistically significantly low for the various zirconia materials. Aging of various zirconia materials showed statistically significant effect of aging on glazed specimens was not statistically significant. There was no significant difference in the tetragonal phase content of all VITA YZ materials (p > 0.05). There was significant difference in the cubic phase content of all VITA YZ materials (p < 0.05). On the other hand, aging process as well as the interaction between the material type and aging had no significant effect on the cubic phase content of YZ specimens (p > 0.05). There was significant difference in the rhombohedral phase of all VITA YZ materials as well as aging process (p < 0.05). CONCLUSIONS: Biaxial flexural strength was significantly affected by glazing, type of material, treatment protocol. Biaxial flexural strength was significantly affected by the interaction between type of material and treatment protocol, glazing and type of material. The VITA YZ ST control had the lowest surface roughness among all the groups. The difference was statistically significant. The type of material, aging, and the interaction effect between the material and aging were significantly different for XRD in non-glazed material. The VITA YZ T showed the lowest mean of yttrium oxide (Y2O3) molecular fraction. On the other hand, YZ XT showed the highest mean of Yttrium oxide (Y2O3) molecular fraction.

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