Increasing PM2.5 (particulate matter smaller than 2.5 micrometers) poses a significant health risk to people. Understanding variables critical to PM2.5 spatial and temporal variation is a first step towards protecting vulnerable populations from exposure. Previous studies investigate variables responsible for PM2.5 variation but have a limited temporal span. Moreover, although land-use classes are often taken into account, the vertical environment's influence (e.g., buildings, trees) on PM2.5 concentrations is often ignored and on-road circle buffers are used. To understand variables most critical to PM2.5 concentration variation, an air pollution sensor and GPS unit were affixed to a bicycle to sample for variables over three seasons (spring, summer, fall). Samples were taken on a route during the weekdays at four targeted hours (7AM, 11AM, 3PM, and 7PM) and joined with meteorological data. 3D morphology was assessed using LiDAR data and novel wind-based buffers. Wind speed only, wind direction only, and wind speed and direction buffers were computed and compared for their performance at capturing micro-scale urban morphological variables. Zonal statistics were used to compute morphological indicators under different wind assumptions in seasonal ordinary least squares regression models. A comprehensive wind and buffer performance analysis compares statistical significance for spatial and temporal variation of PM2.5. This study identifies the best wind parameters to use for wind-based buffer generation of urban morphology, which is expected to have implications for buffer design in future studies. Additionally, significant exposure hotspots for UNT students to PM2.5 pollution are identified.

Parameter estimation of respiratory infection surveillance dynamics commonly utilize data aggregated over space and time. However, estimates derived from aggregated data may fail to account for biologically meaningful spatiotemporal heterogeneity of effects or to identify where and when transmissions occur. This dissertation shows that high-resolution temporal and spatial data can improve our understanding of heterogeneity while producing more valid and precise estimates of transmission parameters (e.g., contagiousness), behavioral trends (e.g., face mask utilization), and intervention effects (e.g., at-home test distribution). In three projects, we evaluate spatiotemporal heterogeneity in the context of two major respiratory pathogens: Tuberculosis and SARSCoV-2. First, in project one, we identify disease transmission hotspots from a tuberculosis case surveillance system in Greater Vitória, Brazil. Utilizing a human mobility model and recently developed method to quantify disease transmission, we overcome multiple methodological constraints that often obscure spatially and temporally accurate transmission measurements. We estimate that two cities in Greater Vitória, Vila Velha (reproductive number = 1.05, 95%CI: 1.03–1.07) and Vitória (reproductive number = 1.04, 95%CI: 1.02–1.06), help sustain tuberculosis transmission in the entire region and may be effective targets for intervention, while Cariacica (reproductive number = 0.95, 95%CI: 0.94–0.97) fell below the critical threshold of 1 required to sustain transmission alone. Next, in project two, we utilize interrupted time series methods to estimate the effect of mask mandates on mask adherence using a nationally representative digital health survey on masking and a comprehensive database of pandemic-related government policies. The analysis focuses on improving previous attempts at measuring the effectiveness of mask mandates at the state level, by utilizing county-level exposure and outcome data. We find that mask mandates were associated with a large heterogeneity of effects, ranging from increasing masking approximately 8% in counties with low levels of prior masking to 1% or lower change in masking in places like the Northeast U.S. where masking levels were already high. Last, in project three, we leverage the same nationally representative digital health survey to understand at-home testing patterns in the United States. We utilize two different economic measures of resource allocation and a regression model with autoregressive integrated moving average errors to examine if the Covidtests.gov government program reduced at-home testing inequities. We show that Covidtest.gov did increase at-home testing across all demographics; however, income-, geographic- and race-based disparities in at-home test utilization were heightened during periods when the program was active. Specifically, the regression results estimate that Theil’s T, an economic metric used here to measure at-home testing disparities, was 53% (95%CI: 6%–121%) higher for household income, 214% (95%CI: 86%–429%) higher for race, and 90% (95%CI: 23%–193%) higher for geography during Covidtest.gov dissemination periods. Disparities were not elevated for age. Together, these three projects demonstrate the substantial role that high-resolution data can play in improving our understanding of respiratory infection surveillance and informing effective public health interventions.

Mesoscale models are needed to predict the effect of changes to the microstructure of plastic-bonded explosives on their shock initiation and detonation behaviour. This thesis describes the considerable progress that has been made towards a mesoscale model for two HMX-based explosives PBX9501 and EDC37. In common with previous work in the literature, the model is implemented in hydrocodes that have been designed for shock physics and detonation modelling. Two relevant physics effects, heat conduction and Arrhenius chemistry, are added to a one-dimensional Lagrangian hydrocode and correction factors are identified to improve total energy conservation. Material models are constructed for the HMX crystals and polymer binders in the explosives, and are validated by comparison to Hugoniot data, Pop-plot data and detonation wave profiles. One and two-dimensional simulations of PBX9501 and EDC37 microstructures are used to investigate the response of the bulk explosive to shock loading. The sensitivity of calculated temperature distributions to uncertainties in the material properties data is determined, and a thermodynamic explanation is given for time-independent features in temperature profiles. Hotspots are widely accepted as being responsible for shock initiation in plastic-bonded explosives. It is demonstrated that, although shock heating of crystals and binder is responsible for temperature localisation, it is not a feasible hotspot mechanism in PBX9501 and EDC37 because the temperatures generated are too low to cause significant chemical reaction in the required timescales. Critical hotspot criteria derived for HMX and the binders compare favourably to earlier studies. The speed of reaction propagation from hotspots into the surrounding explosive is validated by comparison to flame propagation data, and the temperature of the gaseous reaction products is identified as being responsible for negative pressure dependence. Hotspot size, separation and temperature requirements are identified which can be used to eliminate candidate mechanisms in future.

在全球WLAN產業發展迅速的現在，如何能將PWLAN服務快速地商業化，是目前推展WLAN產業最重要的一項課題。目前PWLAN產業尚未建立明確的產業規則，其價值鏈與價值活動都仍在渾沌未明、不斷變動的狀態中，PWLAN業者同時從事多個相關的價值活動的情況相當常見，整體產業動態非常模糊。 在2003年時，已有超過全球80％比例的WLAN硬體設備是在台灣製造的，但是在PWLAN產業的發展推廣方面，卻是起步較晚的。本論文即是希望能夠研究討論國內外PWLAN產業的發展態勢，藉由研究國外公司的發展經驗與競合狀況，再整合國內外學者專家的意見與研究報告，提出PWLAN產業的整體性分析研究與建議，提供台灣PWLAN產業中各從事不同價值活動單元企業的一個營運參考與發展依據。 在最後結論與建議的部分，簡單整理如下： 1.PWLAN產業之發展必須從提升需求與強化供給兩方面做起； 2.而PWLAN業者面臨強大的競爭壓力，在經營上必須步步為營； 3.需注意無線網路為人詬病的安全性問題； 4.注意產業主導權的爭奪； 5.政府角色對台灣PWLAN產業發展的影響力不容小覷； 6.需建立漫遊機制； 7.可能會出現業者間的併購行為； 8.雙網整合的趨勢明顯。

La recombinaison méiotique initiée en prophase I de méiose génère soit des crossing-over (COs), qui sont des échanges réciproques entre segments chromosomiques, ou des conversions géniques non associées aux COs (NCOs). Les deux types d'événements se produisent dans de petites régions (moins de 10 kilobases) appelées points chauds, qui sont distribuées de manière non homogène le long des chromosomes. L'objectif de ma thèse était la caractérisation d'un point chaud de recombinaison méiotique (nommée 14a) chez Arabidopsis thaliana (i) dans différentes accessions (ii) dans le mutant msh4, un gène impliqué dans la formation des COs. Dans les deux hybrides ColxLer et ColxWs (i) 14a a un taux très élevé de COs 0,85% et 0,49%, respectivement (ii) Les COs sont regroupés dans deux petites régions de quelques kilobases, 14a1 et 14a2 avec une distribution de type gaussienne observée aux points chauds décrits dans d'autres espèces (iii) 14a1 est aussi un point chaud de NCO avec un taux aussi élevé que celui des COs (0,5%) dans ColxLer (iv) un biais de l'initiation de recombinaison a été trouvé dans 14a1 aussi bien pour les COs que les NCOs dans le fond génétique ColxLer.Une réduction de la fréquence de CO a été observée dans le mutant msh4 dans le fond génétique ColxLer à 14a1 et 14a2 (6,4% et 18,7% par rapport au sauvage). Cela confirme le rôle précédemment connu de la protéine MSH4 impliqué dans la formation de CO. La fréquence de NCO à 14a1 est similaire à celle observéedans le fond sauvage. Le rôle des H3K4 histones trimethyltransferase d’Arabidopsis dans la recombinaison méiotique (comme précédemment observé comme Set1 chez S. cerevisiae ou PRDM9 chez les mammifères) a également été étudiée. Aucun des dix gènes d’histones méthyltransférase étudié n'a montré de rôle dans la méiose. Cela pourrait être dû à (i) une forte redondance de la fonction entre les protéines (ii) une autre histone méthyltransférase en charge de l'étiquetage des points chauds de recombinaison méiotique (plus de 29 putatif histone méthyltransférase ont été identifiés dans le génome d'Arabidopsis!) (iii) contrairement à S. cerevisiae, les souris et l'homme, un autre mécanisme de contrôle épigénétique de la recombinaison méiotique. / Meiotic recombination initiated in prophase I of meiosis generates either crossovers (COs), which are reciprocal exchanges between chromosome segments, or gene conversion not associated to crossovers (NCOs). Both kinds of events occur in narrow regions (less than 10 kilobases) called hotspots, which are distributed non-homogenously along chromosomes. The aim of my PhD was the characterization of a hotspot of meiotic recombination (named 14a) in Arabidopsis thaliana (i) across different accessions (ii) in msh4 mutant, a gene involved in CO formation. In both ColxLer and ColxWs hybrids (i) 14a had a very high rate of COs 0.85% and 0.49%, respectively (ii) COs clustered in two small regions of a few kilobases, 14a1 and 14a2 with typical Gaussian curve distribution observed in other organisms (iii) 14a1 was also a hotspot of NCO with high rate (0.5%) in ColxLer (iv) a bias of recombination initiation at 14a1 CO and NCO hotspot was found in ColxLer. A reduction of CO frequency was observed in msh4 mutant in ColxLer background at 14a1 (6.4%) and 14a2 (18.7%) compared to wild type. This confirmed previously known role of MSH4 protein in CO formation. Frequency of NCO at 14a1 was similar to wild type. The role of putative Arabidopsis histone H3K4 trimethyltransferase in meiotic recombination as previously observed like Set1 in S.cerevisiae or PRDM9 in mammals (mice and human) was also studied. None of ten putative histone methyltransferase genes was involved in meiosis. This could be due to (i) a strong redundancy of function between gene products (ii) another histone methyltransferase in charge of labeling meiotic recombination hotspots (more than 29 putative histone methyltransferase have been identified in the Arabidopsis genome!) (iii) contrary to S. cerevisiae, mice and humans, another mechanism for epigenetic control of meiotic recombination

Investigations of the textile industry and apparel sector often reveal unethical behaviours towards workers and lack of transparency in the value chain.  As consumers are getting more conscious and the external pressure and demand for more sustainable clothing increases, companies need to implement management systems to control their operations and ensure actions are socially responsible. The Social Life Cycle Assessment (S-LCA) methodology published by the United Nations Environment Programme in 2009 are suggested to measure positive and negative social impacts on stakeholders along a products entire life cycle, from cradle to grave. The methodology is still under development and no methods have yet been standardized or internationally recognized.   To contribute to the development of the S-LCA and its practical use in real world situations, the present study aims to evaluate the applicability of existing methodologies and tools by applying them to a cotton shirt from a small company in Sweden. The case study was performed by conducting an S-LCA following the four phases: Goal and scope; Life Cycle Inventory; Life Cycle Impact Assessment and; Life Cycle Interpretation. Generic country-level data and organisation specific data were collected through questionnaires, document review and desktop screening, while two different assessment tools were tested for the different data types. For generic country-level data, a Social Hotspot Assessment framework developed for this study, was applied and evaluated. For organisation specific data the existing Subcategory Assessment Method (SAM) was subject for feasibility evaluation.   The S-LCA conduction involved several application issues that affect the perceived applicability and feasibility of the methods. Problems identified relate to the definition of system boundaries and uncertainties in the choice of appropriate and relevant indicators. The major problems refer to data collection both in terms of availability and quality issues both with regards to the inventory and assessment phase. Further, in the assessment and interpretation phase uncertainties regarding assessment criteria’s and aggregation of results evolved when using the framework for identifying hotspots, affecting the reliability of the results.   Despite the identified issues, it is evident that it is possible to conduct and finalise a Social Hotspot Assessment using the methodology. However, based on the reliability issues of the results and the effort it requires, it is concluded that the applied framework is not feasible for smaller clothing companies with limited resources. The assessment of organisation specific data by applying SAM, is considered incomplete and identified issues reflect the incompatibility of the method and are thus not considered applicable or feasible for smaller companies.

A new apatite (U-Th)/He (AHe) dataset from subvertical transects collected in the Teton and Gallatin Ranges in the Teton-Yellowstone region provides insight for the slip history and length of the Teton fault. Along the northernmost segment of the Teton fault, inverse thermal history modeling of AHe data from Eagles Rest Peak yield a ~9 Ma age for onset of fault slip. This age supports previous interpretations that Mount Moran may be the true center of the Teton fault. This refined interpretation coupled with lengthdisplacement fault scaling analysis and previous estimates of total fault displacement (~6 km) indicates that the Teton fault may extend 50-90 km north of Mount Moran. However, this new data precludes the possibility that the Teton and East Gallatin faults represent the same structure. Yet, because these systems share a similar structure trend and initial slip ages (13 Ma and 16 Ma, respectively), they may still be related at a larger scale. To the south, the Teewinot transect yields the oldest onset age of ~32 Ma, however a >500 m vertical data gap in this transect leads us to cautiously interpret the results of this model, particularly as this age conflicts with four other transects along-strike.

While 3D stacked multi-processor technology offers the potential for significant computing advantages, these architectures also face the significant challenge of small, localized hotspots with very large heat fluxes due to the placement of asymmetric cores, heterogeneous devices and performance driven layouts. In this thesis, a new thermal management solution is introduced that seeks to maximize the performance of microprocessors with dynamically managed power profiles. To mitigate the non-uniformities in chip temperature profiles resulting from the dynamic power maps, solid-liquid phase change materials (PCMs) with an embedded heat spreader network are strategically positioned near localized hotspots, resulting in a large increase in the local thermal capacitance in these problematic areas. Theoretical analysis shows that the increase in local thermal capacitance results in an almost twenty-fold increase in the time that a thermally constrained core can operate before a power gating or core migration event is required. Coupled to the PCMs are solid state coolers (SSCs) that serve as a means for fast regeneration of the PCMs during the cool down periods associated with throttling events. Using this combined PCM/SSC approach allows for devices that operate with the desirable combination of low throttling frequency and large overall core duty cycles, thus maximizing computational throughput. The impact of the thermophysical properties of the PCM on the device operating characteristics has been investigated from first principles in order to better inform the PCM selection or design process. Complementary to the theoretical characterization of the proposed thermal solution, a prototype device called a "Composite Thermal Capacitor (CTC)" that monolithically integrates micro heaters, PCMs and a spreader matrix into a Si test chip was fabricated and tested to validate the efficacy of the concept. A prototype CTC was shown to increase allowable device operating times by over 7X and address heat fluxes of up to ~395 W/cm2. Various methods for regenerating the CTC have been investigated, including air, liquid, and solid state cooling, and operational duty cycles of over 60% have been demonstrated.

As the semiconductor technology roadmap further extends, the development of next generation silicon systems becomes critically challenged. On the one hand, design and manufacturing closures become much more difficult due to the widening gap between the increasing integration density and the limited manufacturing capability. As a result, manufacturability issues become more and more critically challenged in the design of reliable silicon systems. On the other hand, the continuous scaling of feature size imposes critical issues on traditional interconnect materials (Cu/Low-K dielectrics) due to power, delay and bandwidth concerns. As a result, multiple classes of new materials are under research and development for future generation technologies. In this dissertation, we investigate several critical Computer-Aided Design (CAD) challenges under advanced nanolithography and nanophotonics technologies. In addressing these challenges, we propose systematic CAD methodologies and optimization techniques to assist the design of high-yield and high-performance integrated circuits (IC) with low power consumption. In Very Large Scale Integration (VLSI) CAD for nanolithography, we study the manufacturing variability under resolution enhancement techniques (RETs) and explore two important topics: (1) fast and high fidelity lithography hotspot detection; (2) generic and efficient manufacturability aware physical design. For the first topic, we propose a number of CAD optimization and integration techniques to achieve the following goals in detecting lithography hotspots: (a) high hotspot detection accuracy; (b) low false-positive rate (hotspot false-alarms); (c) good capability to trade-off between detection accuracy and false-alarms; (d) fast CPU run-time; and (e) excellent layout coverage and computation scalability as design gets more complex. For the second topic, we explore the routing stage by incorporating post-RET manufacturability models into the mathematical formulation of a detailed router to achieve: (a) significantly reduced lithography-unfriendly patterns; (b) small CPU run-time overhead; and (c) formulation generality and compatibility to all types of RETs and evoling manufacturing conditions. In VLSI CAD for nanophotonics, we focus on three topics: (1) characterization and evaluation of standard on-chip nanophotonics devices; (2) low power planar routing for on-chip opto-electrically interconnected systems; (3) power-efficient and thermal-reliable design of nanophotonics Wavelength Division Multiplexing for ultra-high bandwidth on-chip communication. With simulations and experiments, we demonstrate the critical role and effectiveness of Computer-Aided Design techniques as the semiconductor industry marches forward in the deeper sub-micron (45nm and below) domain. / text

This dissertation analyzes the spatial distribution and kinematics of the Late Cenozoic Basin and Range (BR) and cross normal fault (CF) systems and their related graben basins around the Snake River Plain (SRP), and investigates the spatio-temporal patterns of lavas that were erupted by the migrating Yellowstone hotspot along the SRP, applying a diverse set of GIS-based spatial statistical techniques. The spatial distribution patterns of the normal fault systems, revealed by the Ripley's K-function, display clustered patterns that correlate with a high linear density, maximum azimuthal variation, and high box-counting fractal dimensions of the fault traces. The extension direction for normal faulting is determined along the major axis of the fractal dimension anisotropy ellipse measured by the modified Cantor dust method and the minor axis of the autocorrelation anisotropy ellipse measured by Ordinary Kriging, and across the linear directional mean (LDM) of the fault traces. Trajectories of the LDMs for the cross faults around each caldera define asymmetric sub-parabolic patterns similar to the reported parabolic distribution of the epicenters, and indicate sub-elliptical extension about each caldera that may mark the shape of hotspot’s thermal doming that formed each generation of cross faults. The decrease in the spatial density of the CFs as a function of distance from the axis of the track of the hotspot (SRP) also suggests the role of the hotspot for the formation of the cross faults. The parallelism of the trend of the exposures of the graben filling Sixmile Creek Formation with the LDM of their bounding cross faults indicates that the grabens were filled during or after the CF event. The global and local Moran’s I analyses of Neogene lava in each caldera along the SRP reveal a higher spatial autocorrelation and clustering of rhyolitic lava than the coeval basaltic lava in the same caldera. The alignment of the major axis of the standard deviational ellipses of lavas with the trend of the eastern SRP, and the successive spatial overlap of older lavas by progressively younger mafic lava, indicate the migration of the centers of eruption as the hotspot moved to the northeast.