607 research outputs found
Developing a kiln treatment schedule for sanitizing black walnut wood of the walnut twig beetle
No full text2012 Summer.Includes bibliographical references.Geosmithia morbida is a fungus that causes numerous cankers on branches and trunks of walnut tree species (Juglans spp.), hence the common name "Thousand Cankers Disease" (TCD), which results in widespread morbidity and ultimately, tree mortality. This fungus is vectored by the walnut twig beetle (Pityophthorus juglandis) that feeds aggressively in the bark. Subsequently, cankers develop around the beetle galleries in the phloem. TCD is currently a major concern in Colorado. The beetle and fungus have been identified and confirmed in three states within the native distribution of black walnut trees; if the fungus expands beyond the quarantined counties and throughout the native range of black walnut (J. nigra), it could have devastating impacts on the nut and timber production industries. Black walnut wood products are valuable for their strength properties and rich dark color. Developing a protocol for heat-treating black walnut lumber and logs with bark intact is important so that they can be sanitized and then safely used. The purpose of this research was to determine whether the International Plant Protection Convention (IPPC) International Standards for Phytosanitary Measures (ISPM-15) standards and United States Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS), Plant Protection and Quarantine (PPQ) Treatment T314-a/c regulations are sufficient to kill live beetles in the bark. The thermotolerance of the walnut twig beetles was evaluated by subjecting walnut twig beetle populations at all stages (including eggs, larvae, pupae and adults) to a series of time and temperature regimens. This experiment was conducted from October 2011 to February 2012 by heating walnut twig beetle-infested black walnut wood in a laboratory oven. The heat-treatments were developed based on the ISPM-15 standards and USDA APHIS PPQ Treatment T314-a/c regulation standards centered on internal wood temperature. The treatments ranged from 42°C to 71.1°C (108°F to 160°F) and lasted between 30 and 120 minutes. The ability of adult beetles to emerge was used to evaluate if the treatment was successful. Results from the emergence trials showed that adults were able to survive up to 48°C (118°F) but no survival of any stage of beetle development was detected at 50.1°C (122°F) when wood samples were heated for 30 minutes. Results suggest that walnut twig beetle survival is variable depending on heating conditions, and an internal wood temperature of 56°C (133°F) for 30 minutes should be considered the minimum for safe treatment of walnut lumber and wood with intact bark
Rupp, Jacob F. (Death, 1886-11-06)
No full textAddress: 89 David St.Age at death: 63 yrs137/Pg.15/1886/MW M/Germany/Dr. M. Koehler/Meyer/Walnut HillsOriginal record filed in drawer labeled 'Runk-Ryan'
Applications Of Gabor And Wavelet Expansions To The Radon Transform
No full text. We investigate the relationship between the Radon transform and certain phase space localization functions, namely the continuous Gabor and wavelet transforms. We derive inversion formulas for the Radon transform based on the Gabor and wavelet transform. Some of these formulas give a direct reconstruction of f or of \Delta 1=2 f from the Radon transform data. Others show how the Gabor and wavelet transforms of f or \Delta 1=2 f can be recovered directly from the Radon transform data. We suggest ways in which these formulas can lead to efficient reconstruction algorithms and can be applied to noise reduction in reconstructed images. in Probabilistic and Stochastic Methods in Analysis with Applications, J. S. Byrnes, et al., eds. Kluwer Academic Publishers, Boston, 187--205 (1992). Reprinted with permission of Kluwer Academic Publishers. 0. Introduction. This paper is a report of joint work being undertaken by the author together with Carlos Berenstein of the University of Maryland..
Human Impacts on Forest Biodiversity in Protected Walnut-Fruit Forests in Kyrgyzstan
No full textWe used a spatially explicit model of forest dynamics, supported by empirical field data and socioeconomic data, to examine the impacts of human disturbances on a protected forest landscape in Kyrgyzstan. Local use of 27 fruit and nut species was recorded and modeled. Results indicated that in the presence of fuelwood cutting with or without grazing, species of high socioeconomic impor- tance such as Juglans regia, Malus spp., and Armeniaca vulgaris were largely eliminated from the landscape after 50–150 yr. In the absence of disturbance or in the presence of grazing only, decline of these species occurred at a much lower rate, owing to competi- tive interactions between tree species. This suggests that the current intensity of fuelwood harvesting is not sustainable. Conversely, cur- rent grazing intensities were found to have relatively little impact on forest structure and composition, and could potentially play a positive role in supporting regeneration of tree species. These results indicate that both positive and negative impacts on biodiversity can arise from human populations living within a protected area. Potentially, these could be reconciled through the development of participatory approaches to conservation management within this reserve, to ensure the maintenance of its high conservation value while meeting human needs
Nonperiodic Sampling of Bandlimited Functions on Unions of Rectangular Lattices
No full textIt is shown that a function f 2 L p [\GammaR; R], 1 p ! 1, is completely determined by the samples of f on sets = [ m i=1 fn=2r i g n2Z where R = P r i , and r i =r j is irrational if i 6= j, and of f (j) (0) for j = 1; : : : ; m \Gamma 1. If f 2 C m\Gamma2\Gammak [\GammaR; R], then the samples of f on and only the first k derivatives of f at 0 are required to completely determine f . Higher dimensional analogues of these results, which apply to functions f 2 L p [\GammaR; R] d and C m\Gamma2\Gammak [\GammaR; R] d , are proven. The sampling results are sharp in the sense that if any condition is omitted, there exist nonzero f 2 L p [\GammaR; R] d and C m\Gamma2\Gammak [\GammaR; R] d satisfying the rest. It is shown that the one dimensional sampling sets correspond to Bessel sequences of complex exponentials which are not Riesz bases for L 2 [\GammaR; R]. A signal processing application in which such sampling sets arise naturally is described in deta..
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Balancing ammonia and alkalinity for nitrification at Walnut Creek Wastewater Treatment Plant
No full texttextThe Walnut Creek Wastewater Treatment Plant in Austin, Texas, has recently experienced increasing influent ammonia concentrations. Nitrification, the biological process used to treat ammonia, consumes alkalinity, which makes it difficult to properly treat ammonia while still maintaining the pH above the required discharge level of pH 6. Operators have looked to the addition of chemicals to supplement alkalinity; one creative alkalinity source was CaCO₃ solids, which are generated by the lime-softening process at Davis Water Treatment Plant. In 2011, the utility began transferring solids to Walnut Creek and immediately noticed improvements in both the nitrification efficiency and the effluent pH. However, undissolved solids accumulated at Walnut Creek and had a detrimental effect on the biosolids treatment efficiency at Hornsby Bend Biosolids Management Plant. Ultimately the costs of the poor biosolids treatment forced the utility to examine an alternative alkalinity source. The objective of this thesis is to help Walnut Creek optimize the use of various alkalinity sources to find a long-term solution that will improve the alkalinity and ammonia balance for adequate nitrification. Analysis of the plant’s influent characteristics suggested that industrial users, especially the semiconductor industry, are major contributors of ammonia and sulfate to the wastewater. A theoretical modeling based on chemical equilibrium predicted that using the CaCO₃ solids would provide a maximum alkalinity benefit of 47 mg/L as CaCO₃. Experimental dissolution jar tests were conducted to verify the model predictions and estimate the kinetics of dissolution. Results from these tests showed no significant dissolution of CaCO₃, and that the solids remained unchanged throughout the test. These results indicate that CaCO₃ solids are not recommended to provide alkalinity at Walnut Creek. Finally, the use of Mg(OH)₂ for alkalinity was employed at Walnut Creek and allowed operators to reduce the blowers that provide aeration. To quantify this observation, bubbling column tests were conducted to measure differences in the oxygen transfer rate at various Mg(OH)₂ concentrations. However experimental results did not match the expectations, so future work is required.Civil, Architectural, and Environmental Engineerin
Ostracoda and associated fauna of the Lower Walnut Formation (Lower Cretaceous) of Travis with Williamson Counties, Texas
No full textThe Lower Walnut Formation (Middle Albian) of the Fredericksburg Division (Comanchean Series) in south-central Texas has a very abundant and diverse shallow marine ostracode fauna. Collections of Ostracoda from five measured sections in Travis and Williamson Counties contain twenty-four species belonging to eighteen genera, including Cythereis. Cytherella. Eocytheronteron. Asciocythere and Neocythere. Systematic descriptions of the ostracode fauna are presented, including thirteen new species. Within the Lower Walnut Formation, six facies have been recognized, based on microfaunal, megafaunal and lithological data presented in this paper. The associations of ostracodes and foraminifers, their diversity, and relative and absolute abundances, document these facies. Each facies formed under different paleoenvironmental conditions that are associated with a shallow, carbonate shelf. There is one marker horizon, based on ostracodes, which contains the only known occurrence of Bairdiidae in the Lower Walnut Formation in Travis and Williamson Counties. At the generic level, the ostracode assemblage of the Lower Walnut Formation is similar to the assemblages of the European Aptian, Barremian and Hauterivian Stages. The Lower Walnut species show greater affinity to Aptian species than to those of the Albian.Earth and Atmospheric Sciences, Department o
Theory and design of M-channel maximally decimated quadrature mirror filters with arbitrary M, having the perfect-reconstruction property
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Local inversion of the Radon transform in even dimensions using wavelets
No full text. We use the theory of the continuous wavelet transform to derive inversion formulas for the Radon transform on L 1 " L 2 (R d ). These inversion formulas turn out to be local in even dimensions in the following sense. In order to recover a function f from its Radon transform in a ball of radius R ? 0 about a point x to within error ffl, we can find ff(ffl) ? 0 such that this can be accomplished by knowing the projections of f only on lines passing through a ball of radius R+ ff(ffl) about x. We give explicit a priori estimates on the error in the L 2 and L 1 norms. in Proceedings of the Conference: 75 Years of the Radon Transform (Vienna, 1992), International Press Co., Ltd., 38--58 (1994). 0. Introduction. Given a function f defined on R d , its Radon transform, Rf , is defined by R ` f(s) = Z ` ? f(s` + y) dy; where ` 2 S d\Gamma1 and s 2 R. Rf(`; s) is the integral of f on the hyperplane in R d defined by fx: hx; `i = sg. The backprojection operator is given by..
What Are Kinship Terminologies, and Why Do We Care? A Computational Approach to Analyzing Symbolic Domains
No full textKinship is a fundamental feature and basis of human societies. We describe a set of computational tools and services, the Kinship Algebra Modeler, and the logic that underlies these. These were developed to improve how we understand both the fundamental facts of kinship, and how people use kinship as a resource in their lives. Mathematical formalism applied to cultural concepts is more than an exercise in model building, as it provides a way to represent and explore logical consistency and implications. The logic underlying kinship is explored here through the kin term computations made by users of a terminology when computing the kinship relation one person has to another by referring to a third person for whom each has a kin term relationship. Kinship Algebra Modeler provides a set of tools, services and an architecture to explore kinship terminologies and their properties in an accessible manner
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