The purpose of this thesis was to assess the repeatability and reproducibility of two high-speed macrotexture measuring systems. The first portion of the study collected macrotexture measurements using the two high-speed systems on the Virginia Smart Road facility and validated the reproducibility of the mean profile depth (MPD) measurements with reference CT Meter measurements. The various data sets were then compared with each other. The objective was to determine whether the two systems are collecting repeatable and reproducible data. The analysis showed that the two high-speed systems investigated have good repeatability (0.105 mm for the Ames and 0.113 mm for the SCRIM) when measuring the average MPD of the sections investigated. The two systems produce measurements that are highly-correlated (Ames R2 = 0.9591 and SCRIM R2 = 0.9157) with the reference ones obtained with the CT Meter. While the Ames systems, with the data processed using the Virginia Tech filter, measures MPD values that are very close to those of the CT Meter, with a virtually zero systematic bias. The SCRIM obtains slightly lower readings. The differences are thought to be due to the filtering of the raw pavement elevation measurements used by the SCRIM processing software to eliminate dropout and spikes in the laser measurements. / Master of Science

Spam is an increasing menace in email: 90% of email is spam, and over 90% of spam is sent by botnets---networks of compromised computers under the control of miscreants. In this dissertation, we introduce email spam filtering using network-level features of spammers. Network-level features are based on lightweight measurements that can be made in the network, often without processing or storing a message. These features stay relevant for longer periods, are harder for criminals to alter at will (e.g., a bot cannot act independently of other bots in the botnet), and afford the unique opportunity to observe the coordinated behavior of spammers. We find that widely-used IP address-based reputation systems (e.g., IP blacklists) cannot keep up with the threats of spam from previously unseen IP addresses, and from new and stealthy attacks---to thwart IP-based reputation systems, spammers are reconnoitering IP Blacklists and sending spam from hijacked IP address space. Finally, spammers are "gaming" collaborative filtering by users in Web-based email by casting fraudulent "Not Spam" votes on spam email. We present three systems that detect each attack that uses spammer behavior rather than their IP address. First, we present IP blacklist counter-intelligence, a system that can passively enumerate spammers performing IP blacklist reconnaissance. Second, we present SpamTracker, a system that distinguishes spammers from legitimate senders by applying clustering on the set of domains to which email is sent. Third, we analyze vote-gaming attacks in large Web-based email systems that pollutes user feedback on spam emails, and present an efficient clustering-based method to mitigate such attacks.

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Pavement structural condition plays a critical role in the rate of pavement deterioration, yet most state highway agencies' network-level decision-making processes are primarily based on surface distresses. Despite the limitations of the traditional structural condition measuring devices, some states have experimented with stationary deflection devices for network-level applications. Over the past decade, continuous deflection devices have become capable of measuring the network-level pavement structural condition information. However, since the traffic speed deflection devices use newer technology, there is a need for guidelines on how the state agencies could make use of this information for pavement management decision-making. This dissertation developed processes and enhanced tools to incorporate the pavement structural condition from the TSD into Virginia's network-level pavement management process This first part of the study developed pavement deterioration models for a subset of road networks in Virginia, to show that the pavement structural condition as measured by the TSD has an impact on the rate of deterioration of the surface condition. A structural condition matrix was then developed to augment the treatment selection process currently used by VDOT. Application of the augmented matrix on the tested Interstate network resulted in reducing the percentage of the network requiring CM and increasing the percentage requiring PM and RM. The second part of the study investigated the possibility of using pavement deflection measurements obtained from the TSD for network-level structural evaluation of pavements in Virginia. The study reported that the structural condition obtained with the TSD can replace the structural condition obtained from the FWD that is currently used in the VDOT PMS. The effective structural number (SNeff) calculated from the TSD and FWD had similar distribution, and the calculated consistency between the TSD SNeff and FWD SNeff was higher than the consistency between the SNeff from two repeated sets of FWD measurements. The third part of the study simulated the network level decision-making approaches based on both the structural condition parameter and the surface condition parameter, considering cases with and without the pavement treatment interval. The study reported that network-level decisions based on the pavement surface condition alone can result in significantly different treatment selection, compared to decisions based on the pavement structural condition. The study reported savings of 9% and 11% for cases with and without considering the pavement treatment intervals, using decision-making based on the structural condition. / Doctor of Philosophy / Pavement structural condition plays a critical role in the rate of pavement deterioration, yet most state highway agencies' network-level decision-making processes are primarily based on surface distresses. Despite the limitations of the traditional structural condition measuring devices, some states have experimented with stationary deflection devices for network-level applications. Over the past decade, continuous deflection devices have become capable of measuring the network-level pavement structural condition information. However, since the traffic speed deflection devices use newer technology, there is a need for guidelines on how the state agencies could make use of this information for pavement management decision-making. This dissertation developed processes and enhanced tools to incorporate the pavement structural condition from the TSD into Virginia's network-level pavement management process' This first part of the study developed pavement deterioration models for a subset of road networks in Virginia, to show that the pavement structural condition as measured by the TSD has an impact on the rate of deterioration of the surface condition. A structural condition matrix was then developed to augment the treatment selection process currently used by VDOT. Application of the augmented matrix on the tested Interstate network resulted in reducing the percentage of the network requiring CM and increasing the percentage requiring PM and RM. The second part of the study investigated the possibility of using pavement deflection measurements obtained from the TSD for network-level structural evaluation of pavements in Virginia. The study reported that the structural condition obtained with the TSD can replace the structural condition obtained from the FWD that is currently used in the VDOT PMS. The effective structural number (SNeff) calculated from the TSD and FWD had similar distribution, and the calculated consistency between the TSD SNeff and FWD SNeff was higher than the consistency between the SNeff from two repeated sets of FWD measurements. The third part of the study simulated the network level decision-making approaches based on both the structural condition parameter and the surface condition parameter, considering cases with and without the pavement treatment interval. The study reported that network-level decisions based on the pavement surface condition alone can result in significantly different treatment selection, compared to decisions based on the pavement structural condition. The study reported savings of 9% and 11% for cases with and without considering the pavement treatment intervals, using decision-making based on the structural condition.

Infrastructure systems are critical to sustaining and improving economical growth. Poor condition of infrastructure systems results in lost productivity and reduces the quality of life. Today's global economy forces governments to sustain and renew infrastructure systems already in place in order to remain competitive and productive (GAO, 2008). Therefore, civil engineers and policymakers have been quite interested in the overall quality of the highways and bridges throughout the US (Miller, 2007). Transportation networks are essential parts of the Nation's infrastructure systems. Deterioration due to age and use is the main threat to the level of service observed in surface transportation networks. Thus, highway agencies throughout the United States strive to maintain, repair and renew transportation systems already in place (Miller, 2007). A recent disaster, the collapse of the Minneapolis I-35 W Bridge, once again revealed the importance of infrastructure preservation programs and resulted in debates as to how state departments of transportation (DOTs) should and can preserve the existing infrastructure systems. Therefore, it is essential to establish effective maintenance programs to preserve aging infrastructure systems. The major challenge facing the state highway maintenance managers today is to preserve the road networks at an acceptable level of serviceability subject to the stringent yearly maintenance and rehabilitation (M&R) budgets. Maintenance managers must allocate such limited budgets among competing alternatives, which makes the situation even more challenging. Insufficient use of available smart decision-making tools impedes eliciting effective and efficient maintenance programs. Hence, this thesis presents the development and implementation of a network-level pavement maintenance optimization model which can be used by maintenance managers as a decision-making tool to address the maintenance budget allocation issue. The network-level optimization model is established with the application of the Linear Programming algorithm and is subject to budget constraints and the agencies' pavement performance goals in terms of total lane-miles in each pavement condition state. This tool is developed with Microsoft Office Excel. The tool can compute the optimal amount of investment for each pavement treatment type in a given funding period. Thus, the model enables maintenance managers in highway agencies to develop alternative network-level pavement maintenance strategies through an automated and optimized process rather than using what-if analysis. / Master of Science

Digital supply chain twins (DSCT) are often considered as one of the most promising technologies to efficiently and proactively manage increasingly complex international logistics networks in the future. Despite the recognition of the potential, the concrete development of digital twins of logistics networks is still in earlier stages in practice. Most twins focus on mapping digital twins of logistics assets or sites rather than elevating the technology to a network level. Building on the Nominal Group Technique among 18 logistics managers this study seeks to investigate the requirements of successful DSCT implementation at a network level. The study shows that while there are various technological requirements that need to be created for the development, it is also DSCT-specific intra- and inter-organizational requirements that influence the successful implementation and use of DSCTs.

With the growing need to maintain roadway systems for provision of safety and comfort for travelers, network level decision-making becomes more vital than ever. In order to keep pace with this fast evolving trend, highway authorities must maintain extremely effective databases to keep track of their highway maintenance needs. Florida Department of Transportation (FDOT), as a leader in transportation innovations in the U.S., maintains Pavement Condition Survey (PCS) database of cracking, rutting, and ride information that are updated annually. Crack rating is an important parameter used by FDOT for making maintenance decisions and budget appropriation. By establishing a crack rating threshold below which traveler comfort is not assured, authorities can screen the pavement sections which are in need of Maintenance and Rehabilitation (M&R). Hence, accurate and reliable prediction of crack thresholds is essential to optimize the rehabilitation budget and manpower. Transition Probability Matrices (TPM) can be utilized to accurately predict the deterioration of crack ratings leading to the threshold. Such TPMs are usually developed by historical data or expert or experienced maintenance engineers' opinion. When historical data are used to develop TPMs, deterioration trends have been used vii indiscriminately, i.e. with no discrimination made between pavements that degrade at different rates. However, a more discriminatory method is used in this thesis to develop TPMs based on classifying pavements first into two groups. They are pavements with relatively high traffic and, pavements with a history of excessive degradation due to delayed rehabilitation. The new approach uses a multiple non-linear regression process to separately optimize TPMs for the two groups selected by prior screening of the database. The developed TPMs are shown to have minimal prediction errors with respect to crack ratings in the database that were not used in the TPM formation. It is concluded that the above two groups are statistically different from each other with respect to the rate of cracking. The observed significant differences in the deterioration trends would provide a valuable tool for the authorities in making critical network-level decisions. The same methodology can be applied in other transportation agencies based on the corresponding databases.

O senso de urgência para a preservação do planeta e a gestão responsável das organizações, ocupa uma posição de destaque no início do século XXI, na agenda de corporações, escolas de negócios, governos e organizações sem fins lucrativos. O Principles for Responsible Management Education (PRME) surgiu em 2007, como uma resposta à demanda de organizações participantes do Pacto Global da ONU (UN Global Compact), para a formação de líderes responsáveis e compromissados com o desenvolvimento sustentável. Atualmente a iniciativa PRME tem uma estrutura composta por aproximadamente 700 escolas de negócios, distribuídas em 85 países. Apesar de ser uma rede com mais de 10 anos de existência, com alcance global, nenhuma pesquisa até então investigou o PRME sob o enfoque das redes interorganizacionais e suas variáveis determinantes de efetividade. O objetivo geral desta pesquisa é verificar se o PRME é uma rede interorganizacional efetiva no nível da rede inteira, identificando as relações lógicas das suas características. Uma primeira análise qualitativa de conteúdo investiga documentos institucionais do PRME em busca da comprovação de sua efetividade, posteriormente, são analisados os relatórios de progresso individuais de membros exemplares, chamados PRME Champions, para a avaliação das variáveis que contribuem positivamente para a efetividade no nível da rede. Seis proposições são extraídas da revisão da literatura para serem discutidas empiricamente. As contribuições desta pesquisa são o fornecimento de subsídios teórico-empíricos sobre governança aos stakeholders de redes em busca de efetividade, em especial ao PRME, e a ampliação da compreensão no campo teórico sobre redes interorganizacionais. A pesquisa demonstra efeitos positivos do modo de governança, da estrutura, do funcionamento e do contexto sobre a efetividade no nível da rede inteira. Os dados apresentaram como determinantes da efetividade da rede os seguintes aspectos: existência de controle por organizações externas, organização, sistema de reuniões, agenda escrita, a transparência na comunicação à comunidade externa, o relacionamento dos gestores da rede com agentes externos, a liderança ativa, a liderança em rede, a estabilidade do ambiente, a presença de cultura cívica e o senso de colaboração e cooperação. A existência de comitê de direção, planejamento conjunto da rede, regras formalizadas e a negociação das direções da rede com stakeholders, exercem efeito moderado sobre a efetividade da rede. / The sense of urgency for the preservation of the planet and responsible management of organizations occupies a prominent position in the early 21st century, on the agenda of corporations, business schools, governments, and non-profit organizations. The Principles for Responsible Management Education (PRME) emerged in 2007 as a response to the demand of participating UN Global Compact organizations for the education of responsible and committed leaders in sustainable development. Currently, the PRME initiative has a structure composed of about 700 business schools, distributed in 85 countries. Despite being a network with more than 10 years of existence, with global reach, none research investigated the PRME under the approach of interorganizational networks and their determinants of effectiveness. The general aim of this research is to verify if the PRME is an effective interorganizational network at the whole network level, identifying the logical relations of its characteristics. A first qualitative content analysis investigates PRME institutional documents to prove its effectiveness, and then the individual progress reports of exemplary members, called the PRME Champions, are analyzed for the evaluation of variables that contribute to the effectiveness at the network level. Six propositions are drawn from the literature review to be discussed empirically. The contributions of this research are the provision of theoretical and empirical subsidies on governance to network stakeholders in search of effectiveness, the PRME in particular, and expansion of understanding in the theoretical field on interorganizational networks. Research shows positive effects of governance, structure, functioning, and context on effectiveness at the whole network level. The data presented as determinants of the network effectiveness the following aspects: the existence of external control, meeting organization, written agenda, transparency in communication to the external community, active leadership, network leadership, the relationship of network managers with external agents, the presence of civic culture, and the sense of collaboration and cooperation. The existence of a steering committee, joint planning of the network, formalized rules, and the negotiation of network directions with stakeholders, has a moderate effect on the network effectiveness.