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The continuing growth of Internet-connected devices presents exciting opportunities for future technology. These Internet of Things (IoT) products are being manufactured and interleaved with many everyday activities, which is creating a larger security concern. Sensors will collect previously unimaginable amounts of private and public data and transmit all of it through an easily observable wireless medium in order for other devices to perform data analytics. As more and more devices are produced, many are lacking a strong security foundation in order to be the "first to market." Moreover, current security techniques are based on protocols that were designed for more-capable devices such as desktop computers and cellular phones that have ample power, computational ability, and memory storage. Due to IoT's technological infancy, there are many security challenges without proper solutions. As IoT continues to grow, special considerations and protections must be in place to properly secure this data and protect the privacy of its users. This dissertation highlights some of the major challenges related to IoT and prioritizes their impacts to help identify where gaps are that must be filled. Focusing on these high priority concerns, solutions are presented that are tailored to IoT's constraints. A security feature-based framework is developed to help characterize classes of devices to help manage the heterogeneous nature of IoT devices and networks. A novel physical device authentication method is presented to show the feasibility in IoT devices and networks. Additional low-power techniques are designed and evaluated to help identify different security features available to IoT devices as presented in the aforementioned framework. / Doctor of Philosophy / The Internet has been gaining a foothold in our everyday lives. Smart homes, smart cars, and smart cities are becoming less science fiction and more everyday realities. In order to increase the public’s general quality of life, this new Internet of Things (IoT) technological revolution is adding billions of devices around us. These devices aim to collect unforeseen amounts of data to help better understand environments and improve numerous aspects of life. However, IoT technology is still in its infancy, so there are still many challenges still remaining. One major issue in IoT is the questionable security for many devices. Recent cyber attacks have highlighted the shortcomings of many IoT devices. Many of these device manufacturers simply wanted to be the first in a niche market, ignoring the importance of security. Proper security implementation in IoT has only been done by a minority of designers and manufacturers. Therefore, this document proposes a secure design for all IoT devices to be based. Numerous security techniques are presented and shown to properly protect the data that will pass through many of these devices. The overall goal for this proposed work aims to have an overall security solution that overcomes the current shortfalls of IoT devices, lessening the concern for IoT’s future use in our everyday lives.

This study focuses on conducting a benchmarking analysis for light wheeled and tracked robotic vehicles. Vehicle mobility has long been a key aspect of research for many organizations. According to the Department of Defense vehicle mobility is defined as, "the overall capacity to move from place to place while retaining its ability to perform its primary mission"[1]. Until recently this definition has been applied exclusively to large scale wheeled and tracked vehicles. With new development lightweight ground vehicles designed for military and space exploration applications, the meaning of vehicle mobility must be revised and the tools at our disposal for evaluating mobility must also be expanded. In this context a significant gap in research is present and the main goal of this thesis is to help fill the void in knowledge regarding small robotic vehicle mobility assessment. Another important aspect of any vehicle is energy efficiency. Thus, another aim of this study is to compare the energy needs for a wheeled versus tracked robot, while performing similar tasks. The first stage of the research is a comprehensive review of the state-of-the-art in vehicle mobility assessment. From this review, a mobility assessment criterion for light robots will be developed. The second stage will be outfitting a light robotic vehicle with a sensor suite capable of capturing relevant mobility criteria. The third stage of this study will be an experimental investigation of the mobility capability of the vehicle. Finally the fourth stage will include quantitative and qualitative evaluation of the benchmarking study. / Master of Science

Concrete undergoes volumetric changes throughout its service life. These changes are a result of applied loads and shrinkage. Applied loads result in an instantaneous recoverable elastic deformation and a slow, time dependent, inelastic deformation called creep. Creep without moisture loss is referred to as basic creep and with moisture loss is referred to as drying creep. Shrinkage is the combination of autogeneous, drying, and carbonation shrinkage. The combination of creep, shrinkage, and elastic deformation is referred to as total strain. The prestressed concrete beams in the Chickahominy River Bridge have been fabricated with a lightweight, high strength concrete mixture (LTHSC). Laboratory test specimens have been cast using the concrete materials and mixture proportions used in the fabrication of the bridge beams. Two standard cure and two match cure batches have been loaded for 329 and 251 days, respectively. Prestress losses are generally calculated with the total strain predicted by the American Concrete Institute Committee 209 recommendations, ACI 209, or the European design code, CEB Model Code 90. Two additional models that have been proposed are the B3 model by Bazant and Baweja, and the GL2000 model proposed by Gardner and Lockman. The four models are analyzed to determine the most precise model for the LTHSC mixture. Only ACI 209 considered lightweight aggregates during model development. GL2000 considers aggregate stiffness in the model. ACI 209 was the best predictor of total strain and individual time dependent deformations for the accelerated cure specimens. CEB Mode Code 90 was the best predictor of total strain for the standard cure specimens. The best overall predictor of time dependent deformations was the GL2000 model for the standard cure specimens. / Master of Science

O crescimento econômico acarreta na necessidade de aumento de capacidade de rodovias existentes. Quando localizadas em meia-encostas, muitas vezes estão vinculadas a ocorrências de instabilidade de modo que obras de aumento da capacidade geram grande impacto. O objetivo desta pesquisa é avaliar o aumento de capacidade de um trecho da Rodovia ERS/122, minimizando os impactos através da definição da seção-tipo com dimensões mínimas, segurança para o usuário, e utilização de um material leve como aterro a ser construído na meia encosta. O principal material avaliado para utilização como aterro são restos de pneus triturados, já encontrados no mercado atual. A avaliação desta solução de aterro em meia encosta decorre principalmente do fato de evitar desmontes de rocha que ocasionariam a interrupção do tráfego em uma importante rodovia do estado. Aliado a isso, é baixa a ocorrência de solos de boa qualidade no trecho, de modo que o aterro é geralmente realizado com materiais rochosos de ocorrência local ou materiais importados. A possibilidade de diminuir a utilização de um material nobre a ser explorado na natureza, juntamente com a utilização de materiais que ainda não possuem 100% de destinação adequada, aliada ao baixo peso específico e adequada resistência ao cisalhamento, incentivaram a realização dos estudos. Ensaios de resistência ao cisalhamento e comportamento de compressão foram realizados para avaliar os parâmetros geotécnicos, a fim de obter um modelo geomecânico. Devido aos resultados de teste satisfatórios, tem sido considerado possível o uso de tais materiais. Os parâmetros obtidos em condições de confinamento foram aceitáveis para aterros de rodovias especialmente quando as aparas de pneus foram misturadas com agregados rochosos. Seu uso como um material de aterro pode ser incentivado, a fim de reduzir o uso de rochas naturais, para obter uma utilização adequada de restos de pneus e para gerar uma maior estabilidade dos aterros com a substituição de solos com comportamento geotécnico pobre. Isto é conseguido principalmente pela diminuição do peso do aterro, pela melhoraria das condições de drenagem e pela definição de uma seção transversal geometricamente segura. / Economic growth leads to the need to increase the capacity of existing highways. When crossing natural slopes often are linked to occurrences of instability so that increased work capacity generate big impact. The objective of this research is to evaluate the increase in capacity of a highway stretch ERS / 122, minimizing impacts by setting the standard section with minimum dimensions, but safe for the user, using a lightweight material as fill. The main material evaluated for use as embankment is shredded tire debris, already found on the market. The evaluation of this embankment solution on natural slopes is mainly to avoid rock blasting which would interrupt the traffic on this important State highway. As there is few occurrences of good quality soil near the construction sites, the fills are usually built with local or imported rock materials. The ability to reduce the use of rock to be exploited from nature by the use of recycled materials combined with its low specific weight and adequate shear strength encouraged this study. Tests of shear strength and compression behavior were carried out to evaluate geotechnical parameters in order to obtain a geomechanical model. Due to satisfactory test results the use of such materials has been considered possible. The parameters obtained on confined conditions were acceptable for road fills especially when scrab tires were mixed with rock aggregates. Its use as an embankment material can be incentivatedf in order to reduce the use natural rocks, to obtain an adequate use for tire scraps and to generate a greater stability for embankments as replacement of soils with poor geotechnical behavior. This is achieved mainly by decreasing landfill weight, improving the drainage conditions and definition of geometrically safe embankment cross-section.

Este trabalho tem por objetivo o estudo da viabilidade da utilização de cerâmica vermelha para a confecção de agregados leves de argila calcinada para utilização em concretos estruturais. Inicialmente, foram coletadas amostras de solo de cinco diferentes empresas produtoras de cerâmica vermelha do estado de São Paulo. As massas cerâmicas foram caracterizadas por meio das técnicas de limites de liquidez (LL) e plasticidade (LP), análise granulométrica, análise química e difração de raios X (DRX). Os corpos de prova confeccionados com essas massas cerâmicas, queimados à temperatura de 900ºC, foram caracterizados por meio da avaliação da retração linear, absorção de água, porosidade aparente, massa específica aparente, expansão por umidade e resistência à compressão. Após a caracterização dos corpos de prova de cerâmica vermelha, foram escolhidas duas amostras para a confecção dos agregados leves de argila calcinada. Em seguida, foram confeccionados corpos de prova de concreto com agregados leves de argila calcinada, argila expandida e brita. Os corpos de prova de concreto leve foram caracterizados pelos ensaios de slump, massa específica fresca, teor de ar incorporado, resistência à compressão, resistência à tração, módulo de deformação, retração por secagem, absorção de água, índice de vazios e massa específica aparente. Os resultados desta pesquisa indicaram a viabilidade da produção de agregados leves de argila calcinada para utilização em concretos e os valores da massa específica (1.555 a 1.785 kg/m³) e da resistência à compressão (18,0 a 55,8 MPa) apresentaram-se em um patamar intermediário entre os valores observados para concretos com argila expandida e com basalto. / This paper aims the study the viability of using red ceramic to make calcined clay lightweight aggregates in order to use in structural concrete. At first, soil sample were collected from five different red ceramic producing companies from São Paulo State. Liquid and plastic techniques, particle size analysis, chemical analysis and X-ray diffraction (XRD) were used to characterize ceramic masses. The specimens made from these ceramic masses, burned at the temperature of 900ºC, were characterized by evaluating of linear shrinkage, water absorption, apparent porosity, specific mass, moisture expansion and compressive strength. After the red ceramic specimens characterization, two samples were chosen for the manufacture of calcined clay lightweight aggregates. After that, concrete specimens with calcined clay lightweight aggregate, expanded clay and basalt were made. These concrete specimens were characterized by slump test, fresh specific mass, incorporated air content, compressive strength, tensile strength, modulus of elasticity, water absorption, voids and bulk density. Results of this research indicated the viability of production of calcined clay lightweight aggregate for concrete utilization and the specific mass values (1.555 and 1.785 Kg/m³) and the compressive strength values (18,0 to 55,8 MPa) presented at a intermediated level between those observed for the expanded clay and basalt.

This thesis evaluates the use of High Strength Lightweight Concrete (HSLW) in bridge girders for the I-85 Ramp "B" Bridge crossing SR-34 in Cowetta County, Georgia. This bridge consisted of four spans; all girders were constructed using lightweight expanded slate aggregate. Spans 2 and 3 had a design strength of 10,000 psi, and span 2 was chosen for this research. The BT-54 girders were 107 ft 11½ inches in length. The prestressing strands used in these girders were 0.6 in diameter, grade 270, low relaxation strands. Material properties and member properties were tested. All 5 girders of span 2 were instrumented with vibrating wire strain gages at midspan, as well as with DEMEC inserts for transfer length measurements and with a deflection measurement system. Transfer length measurements found the transfer length of the girders to be 23% less than the values suggested by AASHTO and ACI equations. The deflection measurements showed 4.26 inches of camber at 56-days while the girders were stored at Standard Concrete Products. The camber measurements matched theoretical predictions within 5%. Mechanical property tests found the concrete to be within all design requirements. A stiffness, load test was performed on each of the 5 girders at Standard Concrete Products. The average stiffness value of 8.428 x 106 kip ft2 is recommend for use by GDOT engineers in designing the deck and road profile. This thesis discusses all short term findings from construction to the end of storage. A later report will address long term issues such as creep and shrinkage, as well as the performance of the girders as part of the bridge.

O crescimento econômico acarreta na necessidade de aumento de capacidade de rodovias existentes. Quando localizadas em meia-encostas, muitas vezes estão vinculadas a ocorrências de instabilidade de modo que obras de aumento da capacidade geram grande impacto. O objetivo desta pesquisa é avaliar o aumento de capacidade de um trecho da Rodovia ERS/122, minimizando os impactos através da definição da seção-tipo com dimensões mínimas, segurança para o usuário, e utilização de um material leve como aterro a ser construído na meia encosta. O principal material avaliado para utilização como aterro são restos de pneus triturados, já encontrados no mercado atual. A avaliação desta solução de aterro em meia encosta decorre principalmente do fato de evitar desmontes de rocha que ocasionariam a interrupção do tráfego em uma importante rodovia do estado. Aliado a isso, é baixa a ocorrência de solos de boa qualidade no trecho, de modo que o aterro é geralmente realizado com materiais rochosos de ocorrência local ou materiais importados. A possibilidade de diminuir a utilização de um material nobre a ser explorado na natureza, juntamente com a utilização de materiais que ainda não possuem 100% de destinação adequada, aliada ao baixo peso específico e adequada resistência ao cisalhamento, incentivaram a realização dos estudos. Ensaios de resistência ao cisalhamento e comportamento de compressão foram realizados para avaliar os parâmetros geotécnicos, a fim de obter um modelo geomecânico. Devido aos resultados de teste satisfatórios, tem sido considerado possível o uso de tais materiais. Os parâmetros obtidos em condições de confinamento foram aceitáveis para aterros de rodovias especialmente quando as aparas de pneus foram misturadas com agregados rochosos. Seu uso como um material de aterro pode ser incentivado, a fim de reduzir o uso de rochas naturais, para obter uma utilização adequada de restos de pneus e para gerar uma maior estabilidade dos aterros com a substituição de solos com comportamento geotécnico pobre. Isto é conseguido principalmente pela diminuição do peso do aterro, pela melhoraria das condições de drenagem e pela definição de uma seção transversal geometricamente segura. / Economic growth leads to the need to increase the capacity of existing highways. When crossing natural slopes often are linked to occurrences of instability so that increased work capacity generate big impact. The objective of this research is to evaluate the increase in capacity of a highway stretch ERS / 122, minimizing impacts by setting the standard section with minimum dimensions, but safe for the user, using a lightweight material as fill. The main material evaluated for use as embankment is shredded tire debris, already found on the market. The evaluation of this embankment solution on natural slopes is mainly to avoid rock blasting which would interrupt the traffic on this important State highway. As there is few occurrences of good quality soil near the construction sites, the fills are usually built with local or imported rock materials. The ability to reduce the use of rock to be exploited from nature by the use of recycled materials combined with its low specific weight and adequate shear strength encouraged this study. Tests of shear strength and compression behavior were carried out to evaluate geotechnical parameters in order to obtain a geomechanical model. Due to satisfactory test results the use of such materials has been considered possible. The parameters obtained on confined conditions were acceptable for road fills especially when scrab tires were mixed with rock aggregates. Its use as an embankment material can be incentivatedf in order to reduce the use natural rocks, to obtain an adequate use for tire scraps and to generate a greater stability for embankments as replacement of soils with poor geotechnical behavior. This is achieved mainly by decreasing landfill weight, improving the drainage conditions and definition of geometrically safe embankment cross-section.

O crescimento econômico acarreta na necessidade de aumento de capacidade de rodovias existentes. Quando localizadas em meia-encostas, muitas vezes estão vinculadas a ocorrências de instabilidade de modo que obras de aumento da capacidade geram grande impacto. O objetivo desta pesquisa é avaliar o aumento de capacidade de um trecho da Rodovia ERS/122, minimizando os impactos através da definição da seção-tipo com dimensões mínimas, segurança para o usuário, e utilização de um material leve como aterro a ser construído na meia encosta. O principal material avaliado para utilização como aterro são restos de pneus triturados, já encontrados no mercado atual. A avaliação desta solução de aterro em meia encosta decorre principalmente do fato de evitar desmontes de rocha que ocasionariam a interrupção do tráfego em uma importante rodovia do estado. Aliado a isso, é baixa a ocorrência de solos de boa qualidade no trecho, de modo que o aterro é geralmente realizado com materiais rochosos de ocorrência local ou materiais importados. A possibilidade de diminuir a utilização de um material nobre a ser explorado na natureza, juntamente com a utilização de materiais que ainda não possuem 100% de destinação adequada, aliada ao baixo peso específico e adequada resistência ao cisalhamento, incentivaram a realização dos estudos. Ensaios de resistência ao cisalhamento e comportamento de compressão foram realizados para avaliar os parâmetros geotécnicos, a fim de obter um modelo geomecânico. Devido aos resultados de teste satisfatórios, tem sido considerado possível o uso de tais materiais. Os parâmetros obtidos em condições de confinamento foram aceitáveis para aterros de rodovias especialmente quando as aparas de pneus foram misturadas com agregados rochosos. Seu uso como um material de aterro pode ser incentivado, a fim de reduzir o uso de rochas naturais, para obter uma utilização adequada de restos de pneus e para gerar uma maior estabilidade dos aterros com a substituição de solos com comportamento geotécnico pobre. Isto é conseguido principalmente pela diminuição do peso do aterro, pela melhoraria das condições de drenagem e pela definição de uma seção transversal geometricamente segura. / Economic growth leads to the need to increase the capacity of existing highways. When crossing natural slopes often are linked to occurrences of instability so that increased work capacity generate big impact. The objective of this research is to evaluate the increase in capacity of a highway stretch ERS / 122, minimizing impacts by setting the standard section with minimum dimensions, but safe for the user, using a lightweight material as fill. The main material evaluated for use as embankment is shredded tire debris, already found on the market. The evaluation of this embankment solution on natural slopes is mainly to avoid rock blasting which would interrupt the traffic on this important State highway. As there is few occurrences of good quality soil near the construction sites, the fills are usually built with local or imported rock materials. The ability to reduce the use of rock to be exploited from nature by the use of recycled materials combined with its low specific weight and adequate shear strength encouraged this study. Tests of shear strength and compression behavior were carried out to evaluate geotechnical parameters in order to obtain a geomechanical model. Due to satisfactory test results the use of such materials has been considered possible. The parameters obtained on confined conditions were acceptable for road fills especially when scrab tires were mixed with rock aggregates. Its use as an embankment material can be incentivatedf in order to reduce the use natural rocks, to obtain an adequate use for tire scraps and to generate a greater stability for embankments as replacement of soils with poor geotechnical behavior. This is achieved mainly by decreasing landfill weight, improving the drainage conditions and definition of geometrically safe embankment cross-section.

Este trabalho tem por objetivo o estudo da viabilidade da utilização de cerâmica vermelha para a confecção de agregados leves de argila calcinada para utilização em concretos estruturais. Inicialmente, foram coletadas amostras de solo de cinco diferentes empresas produtoras de cerâmica vermelha do estado de São Paulo. As massas cerâmicas foram caracterizadas por meio das técnicas de limites de liquidez (LL) e plasticidade (LP), análise granulométrica, análise química e difração de raios X (DRX). Os corpos de prova confeccionados com essas massas cerâmicas, queimados à temperatura de 900ºC, foram caracterizados por meio da avaliação da retração linear, absorção de água, porosidade aparente, massa específica aparente, expansão por umidade e resistência à compressão. Após a caracterização dos corpos de prova de cerâmica vermelha, foram escolhidas duas amostras para a confecção dos agregados leves de argila calcinada. Em seguida, foram confeccionados corpos de prova de concreto com agregados leves de argila calcinada, argila expandida e brita. Os corpos de prova de concreto leve foram caracterizados pelos ensaios de slump, massa específica fresca, teor de ar incorporado, resistência à compressão, resistência à tração, módulo de deformação, retração por secagem, absorção de água, índice de vazios e massa específica aparente. Os resultados desta pesquisa indicaram a viabilidade da produção de agregados leves de argila calcinada para utilização em concretos e os valores da massa específica (1.555 a 1.785 kg/m³) e da resistência à compressão (18,0 a 55,8 MPa) apresentaram-se em um patamar intermediário entre os valores observados para concretos com argila expandida e com basalto. / This paper aims the study the viability of using red ceramic to make calcined clay lightweight aggregates in order to use in structural concrete. At first, soil sample were collected from five different red ceramic producing companies from São Paulo State. Liquid and plastic techniques, particle size analysis, chemical analysis and X-ray diffraction (XRD) were used to characterize ceramic masses. The specimens made from these ceramic masses, burned at the temperature of 900ºC, were characterized by evaluating of linear shrinkage, water absorption, apparent porosity, specific mass, moisture expansion and compressive strength. After the red ceramic specimens characterization, two samples were chosen for the manufacture of calcined clay lightweight aggregates. After that, concrete specimens with calcined clay lightweight aggregate, expanded clay and basalt were made. These concrete specimens were characterized by slump test, fresh specific mass, incorporated air content, compressive strength, tensile strength, modulus of elasticity, water absorption, voids and bulk density. Results of this research indicated the viability of production of calcined clay lightweight aggregate for concrete utilization and the specific mass values (1.555 and 1.785 Kg/m³) and the compressive strength values (18,0 to 55,8 MPa) presented at a intermediated level between those observed for the expanded clay and basalt.