Calculation of Sensitivity Coefficients Using CMAQ-DDM for Individual Airport Emissions in the United States

The Community Multiscale Air Quality (CMAQ) model instrumented with the Direct Decoupled Method in three dimensions (DDM-3D), an advanced method for sensitivity analysis of chemical transport models, is used to quantify individual impacts of large and mid-size US airports on ambient air quality. Sensitivity coefficients are generated for six precursor species groups, allowing estimations of ozone and PM2.5 concentrations from each of 66 individual airports. Airports were divided into groups, minimizing interference and allowing more airports to be analyzed while keeping total simulation runtimes as low as possible. Chorded aviation activity data from the Aviation Environmental Design Tool (AEDT) were used to generate speciated emissions along flight tracks during landing and takeoff (LTO) activities. Sensitivity grids were generated for ozone and primary and secondary components of fine particulate matter for the 66 airports in the domain. Emissions from these airports account for 61% of flights and 77% of fuel burn in the 2005 AEDT inventory; sensitivities from these airports account for 73% of total aviation LTO PM2.5 sensitivities and 57% of total aviation LTO ozone sensitivities in the domain. Aircraft LTO operations for all airports in the domain were found to be responsible for an increase in annual average PM2.5 concentrations of 2.4E-3 ug/m3 nationwide (0.038% of PM2.5 concentrations from all sources), with this level climbing to as high as 0.025 ug/m3 near major airports. Ozone concentrations displayed an annual domain average 8-hr max sensitivity of 1.8E-2 ppbv (0.036% of ozone concentrations from all sources). Sensitivity to PM2.5 precursor emissions from individual airports was often far-reaching. Thirteen airports produced total PM2.5 sensitivities in excess of 1E-3 ug/m3 at 250km, and 52 airports produced sensitivities in excess of 1E-4 ug/m3 at the same distance; sensitivities at these distances tend to be primarily composed of secondary species, while sensitivities closer to airports are balanced more evenly between primary and secondary species. Spatially-resolved estimation of PM2.5 from NAS-wide aircraft LTO operations was calculated to be responsible for an excess all-cause mortality of 131 (95% CI: 121--142) deaths per year. These individual airport sensitivities will be used in the future to generate further estimates of current health and economic impacts of aviation activity, and to inform policy decisions regarding growth and operations in the aviation sector.Master of Scienc

Evaluating Inter-Agency Vehicle Headway Adherence Using AVL Data

A frequent source of frustration for riders of public transit is irregularity in arrival times of the transport vehicles. The use of GPS-based automatic vehicle locator (AVL) services in conjunction with web devices and smart signage can mitigate some of the uncertainty involved in waiting for the transit vehicles and can be used to minimize wait times at the stop; however, regularly unreliable vehicle arrivals can over time impede the use of public transit as a viable alternative to other forms of transportation. A number of factors, including land use, traffic patterns, policy, rolling stock and loading rates influence the tendency of buses to experience headway irregularity. We seek to identify factors associated with the gapping and bunching of buses—identified through gathered AVL data—at a number of cities in the US. By comparing these factors between different transit agencies, I hope to determine if the rates of gapping and bunching are more closely associated with local factors (e.g., land use or ridership) or by latent, agency-wide factors.Master of City and Regional Plannin

Junior Recital: Jared Leach, jazz guitar

This recital is presented in partial fulfillment of requirements for the degree Bachelor of Music in Performance. Mr. Leach studies jazz guitar with Trey Wright.https://digitalcommons.kennesaw.edu/musicprograms/1495/thumbnail.jp

Carbon Free Boston: Transportation Technical Report

Part of a series of reports that includes: Carbon Free Boston: Summary Report; Carbon Free Boston: Social Equity Report; Carbon Free Boston: Technical Summary; Carbon Free Boston: Buildings Technical Report; Carbon Free Boston: Waste Technical Report; Carbon Free Boston: Energy Technical Report; Carbon Free Boston: Offsets Technical ReportOVERVIEW: Transportation connects Boston’s workers, residents and tourists to their livelihoods, health care, education, recreation, culture, and other aspects of life quality. In cities, transit access is a critical factor determining upward mobility. Yet many urban transportation systems, including Boston’s, underserve some populations along one or more of those dimensions. Boston has the opportunity and means to expand mobility access to all residents, and at the same time reduce GHG emissions from transportation. This requires the transformation of the automobile-centric system that is fueled predominantly by gasoline and diesel fuel. The near elimination of fossil fuels—combined with more transit, walking, and biking—will curtail air pollution and crashes, and dramatically reduce the public health impact of transportation. The City embarks on this transition from a position of strength. Boston is consistently ranked as one of the most walkable and bikeable cities in the nation, and one in three commuters already take public transportation. There are three general strategies to reaching a carbon-neutral transportation system: • Shift trips out of automobiles to transit, biking, and walking;1 • Reduce automobile trips via land use planning that encourages denser development and affordable housing in transit-rich neighborhoods; • Shift most automobiles, trucks, buses, and trains to zero-GHG electricity. Even with Boston’s strong transit foundation, a carbon-neutral transportation system requires a wholesale change in Boston’s transportation culture. Success depends on the intelligent adoption of new technologies, influencing behavior with strong, equitable, and clearly articulated planning and investment, and effective collaboration with state and regional partners.Published versio

Generalized Sums over Histories for Quantum Gravity II. Simplicial Conifolds

This paper examines the issues involved with concretely implementing a sum over conifolds in the formulation of Euclidean sums over histories for gravity. The first step in precisely formulating any sum over topological spaces is that one must have an algorithmically implementable method of generating a list of all spaces in the set to be summed over. This requirement causes well known problems in the formulation of sums over manifolds in four or more dimensions; there is no algorithmic method of determining whether or not a topological space is an n-manifold in five or more dimensions and the issue of whether or not such an algorithm exists is open in four. However, as this paper shows, conifolds are algorithmically decidable in four dimensions. Thus the set of 4-conifolds provides a starting point for a concrete implementation of Euclidean sums over histories in four dimensions. Explicit algorithms for summing over various sets of 4-conifolds are presented in the context of Regge calculus. Postscript figures available via anonymous ftp at black-hole.physics.ubc.ca (137.82.43.40) in file gen2.ps.Comment: 82pp., plain TeX, To appear in Nucl. Phys. B,FF-92-

Entanglement over global distances via quantum repeaters with satellite links

We study entanglement creation over global distances based on a quantum repeater architecture that uses low-earth orbit satellites equipped with entangled photon sources, as well as ground stations equipped with quantum non-demolition detectors and quantum memories. We show that this approach allows entanglement creation at viable rates over distances that are inaccessible via direct transmission through optical fibers or even from very distant satellites.Comment: 5+3 pages, 3+2 figure

The Genetics of Pneumothorax.

A genetic influence on spontaneous pneumothoraces-those occurring without a traumatic or iatrogenic cause-is supported by several lines of evidence: 1) pneumothorax can cluster in families (i.e., familial spontaneous pneumothorax), 2) mutations in the FLCN gene have been found in both familial and sporadic cases, and 3) pneumothorax is a known complication of several genetic syndromes. Herein, we review known genetic contributions to both sporadic and familial pneumothorax. We summarize the pneumothorax-associated genetic syndromes, including Birt-Hogg-Dubé syndrome, Marfan syndrome, vascular (type IV) Ehlers-Danlos syndrome, alpha-1 antitrypsin deficiency, tuberous sclerosis complex/lymphangioleiomyomatosis, Loeys-Dietz syndrome, cystic fibrosis, homocystinuria, and cutis laxa, among others. At times, pneumothorax is their herald manifestation. These syndromes have serious potential extrapulmonary complications (e.g., malignant renal tumors in Birt-Hogg-Dubé syndrome), and surveillance and/or treatment is available for most disorders; thus, establishing a diagnosis is critical. To facilitate this, we provide an algorithm to guide the clinician in discerning which cases of spontaneous pneumothorax may have a genetic or familial contribution, which cases warrant genetic testing, and which cases should prompt an evaluation by a geneticist

On the isolated points in the space of groups

We investigate the isolated points in the space of finitely generated groups. We give a workable characterization of isolated groups and study their hereditary properties. Various examples of groups are shown to yield isolated groups. We also discuss a connection between isolated groups and solvability of the word problem.Comment: 30 pages, no figure. v2: minor changes, published version from March 200

Mechanism of imidazolium ionic liquids toxicity in Saccharomyces cerevisiae and rational engineering of a tolerant, xylose-fermenting strain

Additional file 3. Fermentation profiles of Y133 and Y133-IIL in the presence of 1 % [BMIM]Cl at pH 6.5 and pH 5.0, and either aerobic or anaerobic conditions (n = 3, Mean ± S.E, except n = 2 for Y133 pH 6.5 anaerobic 72 h)