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Assessing the Distributional Assumptions in One-Way Regression ModelKasturiratna, Dhanuja 02 June 2006 (has links)
No description available.
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FACTORS AFFECTING THE NEGATIVE DENSITY AREA RELATIONSHIP OF THE WHITE-FOOTED MOUSE (PEROMYSCUS LEUCOPUS)Wilder, Shawn Michael 07 July 2003 (has links)
No description available.
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An Ab-Initio Study on the Chemical Modification of Raman Spectra of Organic Adsorbates on Semiconductor SurfacesKuhlman, Andrew 03 July 2014 (has links)
No description available.
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Denisty functional theory investigations of the ground- and excited-state chemistry of dinuclear organometallic carbonylsDrummond, Michael L. 06 January 2005 (has links)
No description available.
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Effect of Hydraulic Conductivity Heterogeneity on the Movement of Dense and Viscous Fluids in Porous MediaHawkins, Jared B. 15 December 2011 (has links)
No description available.
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High-density housing, low density turnoutRichards, Sophie Marie 25 September 2022 (has links)
Municipal electorates across America are vocal, unrepresentative networks. With lower turnout rates than state and national elections, the local electoral process disproportionately elects white, older, home-owning officials. Voting and elected bodies align demographically, thus leading to a policy that disproportionately reflects the interests of white, older, home-owning voters (Levine Einstein, Ornstein, & Palmer, 2019). This cycle is problematic because it halts the passage of policy that reflects the interest of historically underrepresented voters: young people and people of color. I argue that, for local races, campaign methods disproportionately mobilize the social networks that white, older, home-owning voters belong to. Members of these groups disproportionately occupy low-density housing-building types that can be accessed and mobilized by all campaigns. I suggest a relationship exists between housing density and turnout, with voters residing in low-density housing
participating at higher rates in local elections. Therefore, local races have smaller budgets and fewer reserves to invest in mobilizing voters residing in high-density housing. To assess this relationship, I compare housing density - whether a voter
lives in low density or high-density housing - and individual voting records from 2017 to 2021 across four municipalities in Massachusetts: Cambridge, Boston, Somerville, and Worcester. I expect to find that compared to voters living in low-density housing, those residing in high-density housing - disproportionately young voters and voters of color - are turning out at lower rates in local elections than in the 2018 Midterm and 2020 Presidential Elections. To change this cycle, scholars must pay more attention to the role housing density plays in inhibiting local mobilization efforts, and campaigns must collaborate to mobilize voting members of all social networks, especially those residing in high-density housing.
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Driver Behaviour Modelling: Travel Prediction Using Probability Density FunctionUglanov, Alexey, Kartashev, K., Campean, Felician, Doikin, Aleksandr, Abdullatif, Amr R.A., Angiolini, E., Lin, C., Zhang, Q. 10 September 2021 (has links)
No / This paper outlines the current challenges of driver
behaviour modelling for real-world applications and presents the novel
method to identify the pattern of usage to predict upcoming journeys
in probability sense. The primary aim is to establish similarity between
observed behaviour of drivers resulting in the ability to cluster them
and deploy control strategies based on contextual intelligence and datadriven
approach. The proposed approach uses the probability density
function (PDF) driven by kernel density estimation (KDE) as a probabilistic
approach to predict the type of the upcoming journey, expressed
as duration and distance. Using the proposed method, the mathematical
formulation and programming algorithm procedure have been indicated
in detail, while the case study examples with the data visualisation are
given for algorithm validation in simulation. / aiR-FORCE project, funded as Proof of Concept by the Institute of Digital Engineering
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Stand Density Management for Optimal Volume ProductionAllen, Micky Gale II 22 July 2016 (has links)
The relationship between volume production and stand density, often termed the 'growth-density relationship', has been studied since the beginnings of forestry and yet no conclusive evidence about a general pattern has been established. Throughout the literature claims and counterclaims concerning the growth-density relationship can be found. Different conclusions have been attributed to the diverse range of definitions of volume and stand density among problems with study design and other pitfalls. Using data from two thinning studies representing non-intensively and intensively managed plantations, one spacing trial, and one thinning experiment a comprehensive analysis was performed to examine the growth-density relationship in loblolly pine. Volume production was defined as either gross or net periodic annual increment of total, pulpwood, or sawtimber volume. These definitions of volume production were then related to seven measures of stand density including the number of stems per hectare, basal area per hectare, two measures relative spacing and three measures of stand density index. A generalized exponential and power type function was used to test the hypothesis that volume production follows either an increasing or unimodal pattern with stand density. These patterns were tested using all combinations of the six definitions of volume production and the seven measures of stand density. Significance of the parameters indicated that different patterns existed depending on the type of management (intensive vs. non-intensive), if thinning is performed, and depending on the definitions of growth and density. The growth-density pattern was generally the same between gross and net production although different patterns emerged when comparing total, pulpwood, and sawtimber volumes. The definitions of stand density which used diameter as a measure of average tree size were more highly correlated with volume production and produced similar patterns while the number of stems per hectare was the least correlated. Further analysis was performed to evaluate Langsaeter's hypothesis which states that volume production is constant and optimal across a wide range of stocking. A mixed-model approach was used to test the equality in mean volume production across a range of planting densities and thinning intensities. To account for the effects of age, the equality in mean volume production was tested separately across a range of ages from 8 to 25 years within the spacing trial data and across a range of one to six years since thinning within the thinning experiment. A multiple comparison test indicate that pattern of volume production and stocking is highly related to the two stages of self-thinning. In young stands, within the distance-independent mortality stage, volume production increases with increasing planting density and therefor increasing stocking. During the distance-dependent mortality stage the assumption of constant and optimal volume production across a wide range of stocking is generally correct. However when mortality began to reduce canopy closure to the point that the residual stand could not recover gaps in the canopy a decline in volume production occurred resulting in a decreasing relationship with increasing stocking. Finally, a system of equations were constructed to describe volume production at the individual tree and stand levels. From this model it was determined that stand level volume production follow an increasing pattern with stand density. / Ph. D.
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Enzymatic fuel cells via synthetic pathway biotransformationZhu, Zhiguang 11 June 2013 (has links)
Enzyme-catalyzed biofuel cells would be a great alternative to current battery technology, as they are clean, safe, and capable of using diverse and abundant renewable biomass with high energy densities, at mild reaction conditions. However, currently, three largest technical challenges for emerging enzymatic fuel cell technologies are incomplete oxidation of most fuels, limited power output, and short lifetime of the cell.
Synthetic pathway biotransformation is a technology of assembling a number of enzymes coenzymes for producing low-value biocommodities. In this work, it was applied to generate bioelectricity for the first time. Non-natural enzymatic pathways were developed to utilize maltodextrin and glucose in enzymatic fuel cells. Three immobilization approaches were compared for preparing enzyme electrodes. Thermostable enzymes from thermophiles were cloned and expressed for improving the lifetime and stability of the cell. To further increase the power output, non-immobilized enzyme system was demonstrated to have higher power densities compared to those using immobilized enzyme system, due to better mass transfer and retained native enzyme activities.
With the progress on pathway development and power density/stability improvement in enzymatic fuel cells, a high energy density sugar-powered enzymatic fuel cell was demonstrated. The enzymatic pathway consisting of 13 thermostable enzymes enabled the complete oxidation of glucose units in maltodextrin to generate 24 electrons, suggesting a high energy density of such enzymatic fuel cell (300 Wh/kg), which was several folds higher than that of a lithium-ion battery. Maximum power density was 0.74 mW/cm2 at 50 deg C and 20 mM fuel concentration, which was sufficient to power a digital clock or a LED light.
These results suggest that enzymatic fuel cells via synthetic pathway biotransformation could achieve high energy density, high power density and increased lifetime. Future efforts should be focused on further increasing power density and enzyme stability in order to make enzymatic fuel cells commercially applicable. / Ph. D.
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The Impact of Computational Methods on Transition Metal-containing SpeciesWang, Jiaqi (Physical chemistry researcher) 12 1900 (has links)
Quantum chemistry methodologies can be used to address a wide variety of chemical problems. Key to the success of quantum chemistry methodologies, however, is the selection of suitable methodologies for specific problems of interest, which often requires significant assessment. To gauge a number of methodologies, the utility of density functionals (BLYP, B97D, TPSS, M06L, PBE0, B3LYP, M06, and TPSSh) in predicting reaction energetics was examined for model studies of C-O bond activation of methoxyethane and methanol. These species provide excellent representative examples of lignin degradation via C-O bond cleavage. PBE0, which performed better than other considered DFT functionals, was used to investigate late 3d (Fe, Co, and Ni), 4d (Ru, Rh, and Pd), and 5d (Re, Os, and Ir) transition metal atom mediated Cβ -O bond activation of the β–O–4 linkage of lignin. Additionally, the impact of the choice of DFT functionals, basis sets, implicit solvation models, and layered quantum chemical methods (i.e., ONIOM, Our Own N-layered Integrated molecular Orbital and molecular Mechanics) was investigated for the prediction of pKa for a set of Ni-group metal hydrides (M = Ni, Pd, and Pt) in acetonitrile. These investigations have provided insight about the utility of a number of theoretical methods in the computation of thermodynamic properties of transition metal hydrides in solution. As single reference wavefunction methods commonly perform poorly in describing molecular systems that involve bond-breaking and forming or electronic near-degeneracies and are typically best described with computationally costly multireference wavefunction-based methods, it is imperative to a priori analyze the multireference character for molecular systems so that the proper methodology choice is applied. In this work, diagnostic criteria for assessing the multireference character of 4d transition metal-containing molecules was investigated. Four diagnostics were considered in this work, including the weight of the leading configuration of the CASSCF wavefunction, C02; T1, the Frobenius norm of the coupled cluster amplitude vector related to single excitations and D1, the matrix norm of the coupled cluster amplitude vector arising from coupled cluster calculations; and the percent total atomization energy, %TAE. This work demonstrated the need to have different diagnostic criteria for 4d molecules than for main group molecules.
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