Since the last three decades, several studies have been conducted related to improvement in bearing capacity of pavements, embankments, and shallow foundations resting on geosynthetic reinforced soil. Most of the work has been carried out on single layer soil e.g., sand or clay layer only. Very few studies are available on a double layer soil system; but no study is available on the local soil of Carbondale, Illinois. The present study investigates the physical and engineering properties of a local soil and commonly available sand and improvement in the bearing capacity of a local soil for a rectangular footing by replacing top of the local soil with sand layer and placing geogrids at different depths. Seven tests on the model footing were performed to establish the load versus settlement curves of unreinforced and reinforced soil supporting a rectangular foundation. The improvement in bearing capacity is compared with the bearing capacity of the local soil and double layer unreinforced soil system. The test results focus on the improvement in bearing capacity of local soil and double layer unreinforced soil system in non-dimensional form i.e., BCR (Bearing Capacity Ratio). The results obtained from the present study show that bearing capacity increases significantly with the increasing number of geogrid layers. The bearing capacity for double layer soil increases, by placing three inch sand layer at the top of local soil, was not significant. The bearing capacity of the local soil increased at an average of 7% with three inches sand layer. The bearing capacity for the double layer soil increases with an average of 16.67% using one geogrid layer at interface of soils (i.e., local soil and sand) with u/B equal to 0.67. The bearing capacity for the double layer soil increases with an average of 33.33% while using one geogrid in middle of sand layer having u/B equal to 0.33. The improvement in bearing capacity for double layer soil maintaining u/B equal to 0.33 and h/B equal to 0.33; for two, three and four number geogrid layer were 44.44%, 61.11%, 72.22%, respectively. The results obtained from this research work may be useful for the specific condition or similar type of soil available anywhere to improve the bearing capacity of soil for foundation and pavement design.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22342号 / 医博第4583号 / 新制||医||1042(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 松田 道行, 教授 松田 秀一, 教授 安達 泰治 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

A recent focus in the biomedical engineering field has been on developing models of in-vivo tissue responses to help better predict aortic wall mechanics, through numerical methods and simulation, towards improved prediction of aortic wall rupture. The structural influence of both collagen and elastin, integral components within the aortic wall, has been studied and is largely understood, but the contribution of glycosaminoglycans (GAGs) is still unclear. While it has been suggested that the swelling properties of GAGs may participate in the regulation of residual stresses in the aortic wall, whether or not GAGs affect the mechanical properties of the aortic wall is completely unknown. The present study was divided into two experiments: Experiment 1 (n=9) utilized planar biaxial testing to characterize arterial wall mechanics in native porcine aortas. The results of Experiment 1 highlight: (i) decreased tissue thickness moving distally, away from the heart; (ii) increased stiffness from the ascending aorta to the thoracic descending aorta; (iii) no difference in morphometry or stress-strain behaviour between samples excised from the anterior, posterior, and/or left and right lateral walls. Experiment 2 (n=8) employed identical testing parameters to characterize partial and fully enzymatically GAG-depleted tissue, to determine the influence of this macromolecule on aortic wall mechanics. The results of Experiment 2 highlight: (i) GAG content in the porcine aorta does not affect tissue mechanical properties measured from biaxial testing; (ii) enzymatic removal of GAGs does not influence morphometric parameters, including thickness and area. These findings will contribute to improving the fundamental understanding of aortic tissue mechanics by helping to determine the relationship between spatial dependency and mechanical response, and the relationship between individual aortic wall constituents and the overall mechanical behaviour of the aorta.

No description available.

No description available.

The introduction of ionization under ambient conditions has greatly simplified mass spectrometric analysis. Over past decade, ambient ionization mass spectrometry (MS) methods have revolutionized the way complex samples are analyzed under environmental conditions without requiring, in most cases, any sample pretreatment. Ambient ionization MS gained popularity among other analytical techniques due to its simplicity and its suitability for analysis of small and large molecules. However, ambient ionization methods can suffer from low accuracy and sensitivity due to matrix effects and interferences within complex samples, as well as from poor ionization efficiency. Matrix effects in ambient ionization are usually caused by ion suppression and may depend on different factors, e.g. matrix-to-analyte concentration ratios, proton affinities of analyte and matrix species. To overcome these challenges, in this thesis we present a new approach where a probe is used both as a direct sampling device and as an efficient ambient ionization source. This approach leverages high surface area gold electrodes, fabricated through low-cost bench-top fabrication methods and functionalized using self-assembled alkyl thiol monolayers, as functional conductive sampling probes (FCSPs) for the extraction and concentration of analytes from a sample solution. FCSPs loaded with the targeted analytes were then used to demonstrate a new and highly efficient ionization approach, called Primary Ion Mass Spectrometry Source (PIMSS). In this approach, following capture, the bound analytes are directly desorbed into the mass spectrometer, where ionization is achieved solely through the extraction voltage applied to the probe. 3D-printing was used to design an interface to couple FCSPs to the mass spectrometer. In this work, we discuss a detailed method development and optimization stage and present capabilities of the proposed assay. / Thesis / Master of Science (MSc)

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2014-08-12T13:22:56Z No. of bitstreams: 1 dissertacao andreia assis carvalho.pdf: 1800077 bytes, checksum: 9621151283f1dec9c48115c5ac9df906 (MD5) / Made available in DSpace on 2014-08-12T13:22:56Z (GMT). No. of bitstreams: 1 dissertacao andreia assis carvalho.pdf: 1800077 bytes, checksum: 9621151283f1dec9c48115c5ac9df906 (MD5) Previous issue date: 2010-02-18 / The use of composite resin (CR) in dental restorations is a common practice, however, in the oral environment, these polymers are subject to hygroscopic and hydrolytic effects, and strength of occlusion and mastication. This study aimed to evaluate in vitro the influence of different light sources, energy densities and polymerization techniques on sorption, solubility and biaxial flexural strength (RFB) of an RC. 240 specimens were fabricated (2mm x 8 MMO) RC (Esthet-X), shade A2. Two groups were obtained, depending on the instrument used: halogen lamp and light emitting diodes (LED) and subdivided according to the energy density (16 J/cm2 and 20 J/cm2), polymerization (conventional pulse I stopped and interrupted pulse II) and type of permeant (water and ethanol 75%). The methodology for the development of sorption and solubility test was based on ISO 4049:2000. Then the specimens were tested for RFB (ASTM F 394-78). We used ANOVA and Tukey test for parametric data and Kruskal-Wallis and Mann-Whitney test for data nãoparamétricos (? = 0.05). It was observed that in general there was no statistically significant differences when comparing the sources of light and the polymerization techniques (p> 0.05). Energy density of 16 J/cm2 and pulse interrupted technique II was possible to observe that the LED generated higher values of sorption and solubility of the halogen light and, in the conventional technique, lower RFB (p> 0.05 ). The ethanol produced higher values of sorption and solubility, and lower RFB compared with water. In general, light sources, energy densities and polymerization techniques did not influence the values of sorption, solubility and RFB / O uso de resina composta (RC) em restaurações odontológicas são uma prática frequente, entretanto, no meio bucal, esses polímeros estão sujeitos a efeitos higroscópicos e hidrolíticos, além de forçaa da oclusão e mastigação. Este trabalho teve como objetivo avaliar, in vitro, a influência de diferentes fontes de luz, densidades de energia e técnicas de polimerização na sorção, solubilidade e resistência flexural biaxial (RFB) de uma RC. Foram confeccionados 240 espécimes (2mm x 8 mmØ) de RC (Esthet-X), cor A2. Dois grupos foram obtidos, em função do aparelho utilizado: lâmpada halógena e luz emitida por diodo (LED); e subdivididos de acordo com a densidade de energia (16 J/cm2 e 20 J/cm2), técnica de polimerização (convencional, pulso interrompido I e pulso interrompido II) e tipo de permeante (água deionizada e etanol 75%). A metodologia utilizada para o desenvolvimento do teste de sorção e solubilidade foi baseada na ISO 4049:2000. Em seguida, os espécimes foram testados quanto à RFB (ASTM F 394-78). Foram utilizados os testes ANOVA e Tukey para os dados paramâtricos e os testes Kruskal-Wallis e Mann-Whitney para os dados não paramétricos ( =0,05). Foi observado que, em geral, não houve diferenças estatisticamente significantes quando comparados as fontes de luz e as técnicas de polimerização (p>0,05). Na densidade de energia de 16 J/cm2 e na técnica por pulso interrompido II foi possível observar que o LED gerou maiores valores de sorção e solubilidade do que a lâmpada halógena e, na técnica convencional, menores valores de RFB (p>0,05). O etanol gerou maiores valores de sorção e solubilidade, e menores de RFB quando comparado com a água. Em geral, as fontes de luz, densidades de energia e técnicas de polimerização não influenciaram nos valores de soção, solubilidade e RFB

Infolge des Herstellungsprozesses textiler Bewehrungen ergeben sich unterschiedliche Materialeigenschaften in den beiden Hauptrichtungen (Schuss und Kette). Diese Unterschiede entstehen durch verschiedene Einflussfaktoren, z. B. aus dem Verbundverhalten oder der Querschnittsform der Rovings. Um das Tragverhalten des anisotropen Verbundwerkstoffes Textilbeton experimentell untersuchen zu können, müssen mögliche Einflüsse aus dem Versuchsaubau möglichst gering gehalten werden, bzw. – falls unvermeidbar – in ihrer Wirkung qualitativ und quantitativ bestimmt und bei der Auswertung der Versuchsergebnisse berücksichtigt werden. Auf der Grundlage der durchgeführten umfangreichen experimentellen Untersuchungen wird eine qualitative Bewertung des Versuchsstandes sowie der verwendeten berührungslosen Messtechnik, der Nahbereichsphotogrammetrie, vorgenommen.

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Neste trabalho é apresentado um estudo do efeito da tensão mecânica uniaxial e biaxial no ruído de baixa frequência nos transistores SOI planares e tridimensionais (MuGFETs de porta tripla) com diferentes orientações cristalográficas, além de um estudo das características analógicas nos transistores planares e tipo MuGFET de porta tripla. Nos transistores planares, o estudo do ruído de baixa frequência demonstrou uma melhora para os transistores tensionados no regime de saturação, independente do comprimento de canal, entretanto para a região linear, a tensão mecânica somente reduziu o ruído para um comprimento de canal pequeno (160nm). Nas características analógicas, foi utilizado o recurso da simulação numérica bidimensional para obtenção dos resultados. Os resultados mostram que os transistores tensionados são capazes de promover um melhor desempenho na transcondutância, na ordem de um aumento no mínimo de 40% , indicando para comprimentos longos de canal (910 nm) uma aumento de 56% para tensão mecânica biaxial e o oposto para a uniaxial (45%) (160 nm): entretanto, na condutância de saída, a tensão mecânica de forma geral promove uma maior degradação, aumento de 3% para um transistor uniaxial e aumento de 105% para o transistor biaxial. No ganho intrínseco de tensão, mais uma vez os transistores tensionados melhoraram de desempenho: contudo, neste caso, melhor resultado foi para o transistor biaxial, chegando a 5 dB de ganho. Nos transistores de porta tripla, a análise do ruído foi realizada nos transistores tensionados e convencionais operando em saturação e, de forma geral, a tensão mecânica piora o ruído de baixa frequência em uma ordem de grandeza para o transistor estreito, ocorrendo apenas uma melhora quase imperceptível num transistor largo ou quase planar. Na análise do ruído para os transistores rotacionados para a região linear, apresentaram dependência 1/f, com o ruído governado pela flutuação do número de portadores associado à flutuação na mobilidade: a tensão mecânica piora o ruído, entretanto, adicionando a rotação do substrato, ocorre uma melhora do ruído devido à redução das armadilhas de interface, ocasionando numa melhor interface lateral. Para dispositivos largos, o plano de topo sofre um aumento da concentração das armadilhas, piorando a interface superior devido a rotação do substrato, resultando um pior ruído. Nas características analógicas, os transistores de MuGFETs de porta tripla com tensão mecânica e substrato rotacionado foram estudados, onde a rotação do substrato em 45º mais a presença da tensão mecânica promoveram uma piora nos resultados, principalmente na transcondutância, onde a piora variou de 45 % até 15 %, para um dispositivo estreito (20 nm ) e um largo (870 nm). / This work presents a study of the uniaxial and biaxial mechanical stress effect on low frequency noise in planar and three-dimensional SOI transistors (triple gate) with different crystal orientation, and an study of analog parameters in planar and for triple gate MuGFET. In planar transistor, the study of low frequency noise showed an improvement in low frequency noise for strained transistors in saturation regime, regardless of the channel length, however for the linear regime, the mechanical stress only reduced the noise in a small channel length (160nm). In the analog characteristics was used the feature of two-dimensional numerical simulation for the expansion of the results. The results shows that the strained transistors are capable to promoting a better performance in transconductance in a order at least 40%, indicating for a long channel lengths (910nm) an improvement of 56% in favor of biaxial stress and the opposite to uniaxial (45%) (160nm), however in the output conductance, the mechanical stress promotes higher degradation, ranging from 3% to uniaxial transistor and 105% for biaxial transistor. The intrinsic voltage gain, the strained transistors improved the performance, but in this case a best result was found for the biaxial strain reaching 5 dB. In triple gate transistors, the analysis of noise was performed on strained and conventional operating in saturation, and generally the worsening of mechanical stress on the low frequency noise in a order of magnitude for the marrow transistor, occurring only barely perceptible improvement seen in wider transistor or quasi-planar. The noise analysis for rotated transistors in linear region, showed a 1/f noise characteristic governed by the carrier number of fluctuations associated with fluctuations in mobility, the mechanical stress worsens the noise, however, by adding the substrate rotation occurs improves noise due to reduction of interface traps leading to a better sidewall interface. For larger devices the top plane suffer an increase of interface traps, worsening the top interface due to rotation of the substrate, causing a worse noise. In the analog characteristics, the triple gate MuGFETs transistors with mechanical stress and rotated substrate were studied, where the rotation of the substrate in 45º plus mechanical stress promoted a worsening of the results, particularly in the transconductance, where the worsening ranged from 45% up to 15% for a narrow device (20 nm) and a large (870 nm).