VictorJuiz/thesis huggingface dataset:
Lightweight scheduling and information delivery in wireless networks [electronic resource]

As inherently distributed computational systems, wireless sensor networks rely critically on coordination between nodes to effectively sense, interpret and deliver environmental data. Wireless nodes face significant battery and computational limitations, so a strategy of lightweight and low-communication task coordination is critical to maintaining the longevity and efficient operation of the network. The challenge is to solve network-wide coordination problems, such as scheduling, routing and aggregation, using simple, local operations, such as gossiping, local broadcasting and neighborhood leader election. While each node performs a simple local task, these actions can be carefully aggregated to achieve the desired global solution. In this thesis, we study two key decentralized coordination problems: scheduling and information delivery. In scheduling, where coordination among nodes occurs at the neighborhood level, the problem is for nodes to select timeslots for their actions that do not interfere with those chosen by other nodes in the neighborhood. We employ simple, randomized and rapidly converging iterative algorithms that seek to stagger node behavior while relying as little as possible on potentially expensive inter-node communication. In information delivery, the problem is to build and maintain a delivery infrastructure that enables information dissemination from sources to sinks in the network. Here, we think of the coordination as occurring over longer distances in the network, enabling the required infrastructure to be built in an efficient, decentralized fashion. We employ information delivery "backbones'', like connected dominating sets and hierarchical trees, and show how they can be quickly and easily built and maintained, even when users are mobile and link dynamics affect the network topology.

Advisor: Guibas Leonidas J. primary advisor. Thesis advisor
Plotkin Serge A. advisor. Thesis advisor
Roughgarden Tim advisor. Thesis advisor
Linking Geostatistics with Basin and Petroleum System Modeling: Assessment of Spatial Uncertainties

Basin and Petroleum System Modeling covers a large spatial and temporal interval. Many of the input parameters are highly uncertain. While probabilistic approaches based on Monte Carlo simulations have been used to address some uncertain parameters, the impact of spatial uncertainties remains unexplored. Facies map is one of the key modeling inputs since all the rock properties are wrapped into facies definition. Many techniques had been developed for facies modeling in reservoir characterization regime. These methods can be applied directly in basin modeling. In particular Multi-point Geostatistical Method had been proven to be very effective in modeling categorical variables. Another important spatial parameter is the structure model. Present day structure model is the starting point for reconstruction the deposition history. In this work we first conducted the traditional uncertainty analysis in basin modeling. Then the impact of facies distribution and structure uncertainty from time-to-depth conversion were studied. It is shown that facies distribution has great impact on the oil accumulation and different geological interpretations give quite different results. Structure uncertainty from time-to-depth conversion has less impact in this case because the target area is quite homogeneous and it is expected that structure uncertainty is still the first order uncertainty sources in basin modeling.

Keywords:  Department of Energy Resources Engineering
School of Earth Energy &amp; Environmental Sciences
Thesis
Advisor: Mukerji Tapan
Living the middle life, secular priests and their communities in thirteenth-century Genoa [electronic resource]

Secular priests occupied a central place within thirteenth-century European society, carrying out important duties within the institutional Church, as well as participating in the lay and religious communities around them. This dissertation uses secular sources--the private registers of public notaries--to show that priests in the port city of Genoa entered into economic, spiritual, and social transactions with a wide range of people. In doing so, they built complex and durable relationships that provided ample opportunities for the exchange of ideas and values with the women, men, and other clerics with whom they shared their lives. If a major trend in scholarship on the Middle Ages over the past seventy years has been to emphasize the religiosity of lay people's everyday world, then this dissertation looks the other direction, to explore the so-called secularity of religious institutions and their priests. Ultimately, the notarial registers prove that Genoa's priests were not mere facilitators of lay religiosity or agents of ecclesiastical power; rather they played a multivalent role in the intermediary space between "lay" and "religious" communities. Chapter One provides an overview of Genoa's ecclesiastical structure and demonstrates how private notarial registers can provide useful perspectives on secular priests' lives. Chapter Two investigates how priests' participation in the real estate and credit markets helped weave them into the fabric of Genoese neighborhoods. Chapter Three uses the notarial registers to show priests carrying out their core professional duties: tending to the health of souls in their communities. Chapter Four demonstrates priests' important intermediary position by examining their service as executors, agents, arbiters, and judges. Chapter Five explores how secular priests embodied the Genoese Church overseas in Genoa's network of trading settlements around the Mediterranean and Black Seas. Finally, the Conclusion considers the broader contours of priests' social networks, identifying trends that cut across the heuristic boundaries that structure earlier chapters. It also summarizes the value of the private registers as sources for ecclesiastical and clerical history.

Keywords: History.
Advisor: Miller Kathryn A.
Buc Philippe
Findlen Paula advisor. Thesis advisor
Looking for leveraging [electronic resource] : teacher utilization of a residential science camp to enhance their capacity to teach science

Abstract This study investigated how teachers leverage a multi-day, residential, environmental education program to expand their capacity to teach science through creation of pedagogical links between the classroom and the program. The notion of leveraging was characterized by the presence of identifiable teaching and learning goals constructed by the teacher; the creation of links that supported embedding of the program into a deliberate, purposeful sequence of classroom curriculum; and the creation of links under a subject-matter based conceptual umbrella. Seven case studies were performed that examined the school environment, influences on the teacher, and goals articulated by teachers for the program. Pedagogical links created by the teacher between the program and the classroom were analyzed to determine the teachers' motivations and whether the links reflected the characteristics of leveraging. A cross-case analysis was performed to detect trends in teacher practice. Only one out of seven cases exhibited the three characteristics of leveraging and analysis showed that this teachers' practice did expand his capacity to teach science. Influences that appeared to positively impact leveraging practice included teacher autonomy, academic training in science, and willingness to adopt the program curriculum as critical to his student learning goals, and to adapt the program to meet his teaching goals. The role of the program provider is also discussed as well as the location of the program within an intersection of informal and formal education.

Keywords: Education.
Advisor: Osborne Jonathan primary advisor. Thesis advisor
Shavelson Richard J.
Ardoin Nicole M. (Nicole Michele) advisor. Thesis advisor
Low frequency noise in advanced CMOS technology [electronic resource]

The main topic of this thesis is to investigate the CMOS scaling impacts on low-frequency noise properties. Such effects come from size (channel length/width) scaling, adoption of advanced doping profiles (halo pocket implantation), incorporation of alternative gate oxide (high-[Kappa]) and channel materials (SiGe). Device-level simulation capabilities have been developed to investigate low-frequency noise behavior. The numerical model is based on the impedance field method; it accounts for a trap-induced carrier number fluctuation and a Hooge mobility fluctuation. Simulations based on such models have been conducted for high-[Kappa], SiGe and small gate area transistors, and the results have been correlated with experimental data, which reveals the important role of the CMOS scaling in the low-frequency noise behavior. In the study of high-[Kappa] gate dielectric it is found that carrier number fluctuation becomes the dominant noise source and the non-uniform trap energy distribution is critical to explain low frequency noise behavior. The negative impact of substrate halo doping on the low frequency noise is also studied quantitatively. Low frequency noise characteristics of Si/SiGe/Si hetero-channel MOSFETs (SiGe MOSFETs) are discussed; the study has been obtained in terms of the noise level dependence on gate bias, drain currents, and body bias, revealing the important role of the dual channels in the low-frequency noise behavior of Si/SiGe/Si hetero-channel devices. Low frequency noise characteristics in small gate area MOSFETs are studied in detail. Due to the ever decreasing gate area, the number of charge carriers in a MOSFET channel is continually going down, and single-electron low frequency noise phenomena (random telegraph noise, RTN) becomes visible, which is quite different from 1/f noise in standard MOSFETs. It is found that random telegraph noise is directly linked to Positive Bias Temperature Instability (PBTI): PBTI and RTN originate from the same physical process, charge trapping in the high-[Kappa] dielectric. The correlation between Id- and Ig-RTN is clearly observed. Ig-RTN is directly related to physical trapping or de-trapping and the Id-RTN reflects sensitivity to charge trapping as determined by gm. This dissertation has explored advanced TCAD simulations to overcome obstacles in low frequency noise and explained a comprehensive view and the underlying physics for low frequency noise in advanced CMOS technology.

Keywords: Electrical Engineering
Advisor: Dutton Robert W. primary advisor. Thesis advisor
Murmann Boris advisor. Thesis advisor
Nishi Yoshio
Low-latency and robust peer-to-peer video streaming [electronic resource]

Peer-to-peer (P2P) systems have emerged as a promising and cost-effective transport solution for streaming video to a group of users in the Internet. In the P2P architecture, users not only consume video, but also forward it to other users. Thus, P2P systems scale better than client-server systems as users bring resources to the system. The challenge is to achieve low-latency and robust video dissemination by overcoming a number of adversarial aspects and challenges -- peer dynamics, heterogeneous uplink bandwidth of peers, heterogeneous hardware and capabilities of peers, and peer-wise connection restrictions due to NATs/firewalls. This dissertation presents Stanford Peer-to-Peer Multicast (SPPM), a P2P video streaming system. SPPM is designed to achieve low-latency and robust streaming by constructing an overlay of multiple complementary trees and dynamically rearranging the position of peers by Active Overlay Management in a distributed fashion. Next, we extend SPPM for providing playback control to users by time-shifted streaming. To perform time-shifted streaming, peers store past portions of video and forward them to other users when requested, thereby reducing server load. To further alleviate server load, we propose fast prefetching, by which peers can disseminate content quickly. Finally, we present a way to accommodate mobile users. Video transcoding is often required to adapt video for the mobile users. We propose interleaved distributed transcoding (IDT), which allows a video stream to be transcoded at multiple peers that are more capable than mobile users. IDT is shown not only to reduce computation required at a peer but also to achieve higher error resilience in case of peer failure or packet loss.

Keywords: Electrical Engineering.
Advisor: Girod Bernd primary advisor. Thesis advisor
Baccichet Pierpaolo advisor. Thesis advisor
Tobagi Fouad A.
Magnetic coupled spin-torque device [electronic resource] : spin-based non-volatile logic device and applications

Power consumption has become the key constraint in electronics design, since the MOSFET threshold voltage (Vth) and hence the supply voltage (Vdd) can no longer be scaled. This trend calls for new device concepts such as Spintronic devices that are fundamentally different from CMOS. However, the MOSFET-type Spintronics transistor has not been demonstrated yet due to the technical difficulties in injecting, transporting and detecting spin information. In this work, I present an alternative Spintronics logic device, Magnetic Coupled Spin Torque Device (MCSTD), which is free from spin-injection, transport and detection problems. It leverages spin-torque transfer effect and magnetic dipole coupling between spin-torque devices to modulate its magnetization reversal energy barrier. Its device switching speed, signal inversion and signal level restoration capabilities will be discussed. For device-to-device level spin communication, MCSTD uses a novel interconnection technique that efficiently converts spin (or magneto-resistance) information to current amplitude difference information, which is then converted back to spin information at the subsequent gates. In micro-magnetic simulations, MCSTD-based NAND, NOR, XOR gates and a three-stage ring oscillator have been demonstrated to estimate realistic device speed and power consumption. The fabrication of 20nm gap MCSTDs has been successfully completed and demonstrated the input dependent switching voltage modulation, i.e., switching voltage of MCSTD gate depends on the magnetic orientations of the input spin-torque devices. The amount of voltage shifts ranged between 40~300mV, which is well above thermal fluctuations. Non-volatility in logic device such as MCSTD opens up very unique potential applications in future power management techniques and smart sensor technologies. For example, MCSTDs can replace SRAMs and pass gate transistors in reconfigurable logics such as Field Programmable Gate Array (FPGA). Instant-on/off nature of MCSTD enables low overhead system-level power gating scheme for embedded devices. Also, MCSTD can be used as a magnetic sensor with in-situ logic operations for error-resilient DNA microarray sensors. This work also explored other disruptive low-power device and system solutions such as Graphene nano-ribbon /Carbon nanotube based heterojunction Tunneling FET (Chap.8) and Error Resilient System Architecture for Probabilistic Applications (Chap.9).

Keywords: Electrical Engineering
Advisor: Harris J. S. (James Stewart)
Peumans Peter
White Robert M.
Magnetic nanoparticle-based technologies for lab-on-a-chip applications [electronic resource]

Lab-on-a-Chip devices are attractive for medical diagnostics due to their ability to perform laboratory tasks on small scales. This manuscript explores magnetic nanoparticle-based technologies for low-power, remote actuation in Lab-on-a-Chip systems. Two specific applications -- microfluidic pumping and cell separation -- are investigated. First, chemistry-independent microfluidic pumping using magnetic nanoparticles suspended within a fluid has been demonstrated. Magnetic circuits to generate magnetic field gradients for actuating superparamagnetic nanoparticles in fluids have been fabricated, and changes in fluid velocities when the magnetic circuits are applied have been measured. Results show that the fluid velocity in a microchannel increases 30 [mu]m/sec when a magnetic field gradient of ~3 T/m is applied, and 10 -- 70 [mu]m/sec when a magnetic field gradient of ~5 T/m is applied. The magnetic, optical, and mechanical properties of a magnetic polymer that is composed of SU-8 polymer embedded with nickel nanoparticles (SU8-Ni) have also been characterized. Results show the SU8-Ni composites exhibit weak ferromagnetic behavior and saturate at magnetic fields around 0.2 T, the transmittance of light through SU8-Ni decreases with increasing Ni concentrations, and SU8-Ni has a Young's modulus that is 30 times lower and a hardness that is 1400 times lower than that of bulk Ni. A torsional microactuator made of SU8-Ni has been fabricated to demonstrate its use for magnetic actuation, and a model of the SU8-Ni based on deflection experiments of the actuator has been developed. Micropillars made of SU8-Ni have been fabricated for capturing and concentrating breast cancer cells in microchannels. Magnetic field gradients up to 10,000 T/m have been predicted for an SU8-Ni pillar that is 100 [mu]m tall, 100 [mu]m in diameter, and composed of 12.5% Ni by weight. Experimental results show the SU8-Ni micropillars capture magnetic bead-bound cells when an external magnet is applied and release the cells when the magnet is removed.

Keywords: Electrical Engineering
Advisor: Howe Roger Thomas primary advisor. Thesis advisor
Field Leslie
Pruitt Beth advisor. Thesis advisor
Wang Shan advisor. Thesis advisor
Magnetohydrodynamics, magnetogenesis, and magnetorotational instabilities with adaptive mesh refinement [electronic resource]

While the presence of magnetic fields seems ubiquitous in cosmic structures of all scales, the mechanisms of their formation are still debated. Using the adaptive mesh refinement (AMR) code Enzo, we touch on three major topics in the study of magnetic fields in computational astrophysics. We first describe the features of magnetohydrodynamic algorithms, and develop a technique to computationally maintain the divergence free nature of the magnetic field in an AMR hierarchy. Second, we analyze the generation of magnetic seed fields in protogalaxy formation via a plasma physics phenomenon called the Biermann Battery, and discuss its dependence on turbulence during large scale structure formation in the early universe. Finally, we discuss the magnetorotational instability that causes the saturation of magnetic field generation in differentially rotating objects such as accretion disks. We adapt the shearing box, a local 3D simulation of differentially rotating disks, to the AMR formalism and analyze the resolution and simulation box size dependence of these instabilities.

Keywords: Applied Physics
Advisor: Abel Tom G.
Petrosian Vahe primary advisor. Thesis advisor
Blandford Roger D. advisor. Thesis advisor
Making global warming green [electronic resource] : climate change and American environmentalism, 1957-1992

"Making Global Warming Green: Climate Change and American Environmentalism, 1957-1992" investigates how global climate change became a major issue in American environmental politics during the second half of the 20th Century. The dissertation focuses on the complex institutional, political, and professional relationships between scientists studying climate and America's professional environmentalists during this tumultuous period. Throughout the early history of global warming, the geographical and chronological scales of climatic and atmospheric change transcended the existing legal and regulatory mechanisms of American environmental politics. Only scientists had the technology and expertise to recognize threats to these novel components of the environment, and their exclusive access all but forced them into a prominent role as environmental advocates. But scientists' particular forms of advocacy often reflected the values and interests of their disciplines more than they did the middle-class quality-of-life concerns at the center of the mainstream American environmental movement. Scientists framed climate change in terms of development and natural resources, and they sought to influence elites in government and at international scientific organizations more than they worked to mobilize the American public. As American environmentalists began to take up the fight against global warming in the 1980s and '90s, they too found themselves trading in the language of scientific consensus and government-sponsored global solutions rather than the locally focused, middle-class consumer values originally at the heart of the movement. More than just a political history of global warming, this research presents a new history of American environmentalism that takes into account the science and politics of an issue that has emerged in the twenty-first century as one of our greatest challenges.

Keywords: History.
Advisor: White Richard
Proctor Robert
Riskin Jessica advisor. Thesis advisor
Managing the quality of cost-per-click traffic [electronic resource]

Traffic quality is critical to the security and viability of an online advertising network's business. As such, how might an advertising network detect and avoid paying for low-quality traffic? The online advertising market can be modeled as a large, multiplayer game with three classes of players: publishers, advertisers and advertising networks. We focus on cost-per-click (CPC) traffic, and identify two distinct-but-related aspects of click quality: validity and targetedness. Validity refers to whether a click-through is legitimate, whereas targetedness refers to the likelihood that valid clicks become conversions. We study three techniques that influence traffic quality on a network, namely filtering, predictive pricing and revenue sharing. We begin by asking whether it is in an advertising network's interest to filter (i.e., ensure traffic validity) in the first place. This question has been a topic of intense debate in the industry. Our analysis shows definitively that networks do, indeed, have a strong incentive to aggressively filter out invalid traffic. We then consider how a network might use predictive pricing and revenue sharing to attract targeted, high-conversion-rate traffic. We show that effective usage of predictive pricing can yield a competitive edge for a network, and that targetedness has a quantifiable impact on profits. Finally, we study how validity and targetedness can be managed together. What is the relation between filtering, predictive pricing and revenue sharing? We derive efficient, tractable algorithms for computing near-optimal traffic management policies, and also propose strategies to combat publisher click inflation. Perhaps the most important lessons learned from our work are that a) in the online advertising business, traffic quality has a direct impact on profits, and b) traffic quality is often more important than quantity.

Keywords: Electrical Engineering
Advisor: Garcia-Molina Hector primary advisor. Thesis advisor
Saberi Amin advisor. Thesis advisor
Ullman Jeffrey D.