POLICY ISSUES RELATED TO SMALL-SCALE PART-TIME FARMS IN THE NORTHEAST

Agricultural and Food Policy,

Jackknife Estimator of Species Richness with S-PLUS

An estimate of the number of species, S , usually called species richness by ecologists, in an area is one of the basic statistics used to ascertain biological diversity. Traditionally ecologists have used the number of species observed in a sample, S_0 , to estimate S , realizing that S_0 is a lower bound for S . One alternative to S_0 is to use a nonparametric procedure such as jackknife resampling. For species richness, a closed form of the jackknife estimator is available. Typically statistical software contains only the traditional iterative form of the jackknife estimator. The purpose of this article is to propose an S-PLUS function for calculating the noniterative first order jackknife estimator of species richness and some associated plots and statistics.

Ultraschnelle Relaxation optisch angeregter Elektronen in kleinen Übergangsmetallclustern

In the present dissertation the relaxation dynamics of optically excited electrons in free Ni3, Pd3, Pd4, Pd7, and Pt3 has been investigeted. By means of femtosecond pump-probe photoelectron spectroscopy the electronic relaxations in these small transition metal clusters could be observed for the first time in real-time . A quantitative analysis of the data reveals inelastic electron-electron relaxation times in the order of magnitude of 10 to 100 femtoseconds . These unexpected short electronelectron- scattering times are caused by the relatively large density of states in the vicinity of the highest occupied cluster orbital. This large density of states results from the narrow bandwidth of the partially filled d-levels in the transition metal clusters . Other aspects for the enhancement of inelastic electron-electron scattering are the spread of the electronic levels by vibrational broadening and the spill-out of the s/p-electron wave functions intensifying the Coulomb-interaction between the electrons

A monostrain test apparatus

Test apparatus is designed for determining tensile strength, modulus of elasticity, elongation, and thermal coefficient of contraction or expansion of uniformly shaped plastics, adhesives, and foam materials over temperature range of 700 to 90 K (800 to -300). Tests may be used in design quality control, and in evaluation of new adhesives and plastic materials

Assessing hemlock woolly adelgid induced decline and susceptibility using hyperspectral technologies

The ultimate goal of this study was to provide the scientific framework for using narrow band hyperspectral instruments to assess early hemlock decline and susceptibility to the introduced hemlock woolly adelgid (HWA). To this end, spectral data from an ASD FieldSpec Pro was used to develop a 6-term linear regression equation, which predicted a detailed decline rating (0--10) with an R2 of 0.71 and RMSE of 0.591. To scale up this method to a remote sensing platform, NASA\u27s Airborne Visible Infrared Imaging Spectrometer (AVIRIS) was used to create a hemlock abundance map, correctly identifying hemlock dominated pixels (\u3e40% basal area) with 88% accuracy. Reflectance at a chlorophyll sensitive wavelength (683nm), coupled with a water band index (R970/900), was able to predict decline with 85% accuracy. The extreme accuracy at the low (0--4) end of the range indicated that these wavelengths might be used to assess early decline, before visual symptoms are apparent. Because instruments like AVIRIS have the capability to map foliar chemistry, the identification of links between HWA dynamics and foliar chemistry may be used to map relative susceptibility. To this end, we employed a three-tiered approach examining resistant vs. susceptible hemlock species, foliar chemistry vs. colonization success and regional foliar chemistry vs. HWA population levels. We found that HWA resistant hemlock species demonstrated higher concentrations of Ca and P, and lower concentrations of N and K. Regardless of host species, successful colonization of uninfested hemlocks was associated with higher N, and lower Ca and P concentrations. Regionally, higher concentrations of Ca, Mn, N and P were correlated with higher HWA densities. We hypothesize that higher N and K concentrations may have a palatability effect, driving HWA population levels, while higher concentrations of Ca and P may act as deterrents to more severe infestations. These results indicate that by using hyperspectral remote sensing instruments, it is possible to identify the very early stages of hemlock decline and map relative susceptibility to HWA on a landscape scale. Such tools are instrumental in targeting management activities and ultimately controlling the HWA outbreak

Joint acoustic full-waveform and gravity inversion - development and synthetic application to a salt dome = Simultane Inversion akustischer Wellenformen und gravimetrischer Daten - Entwicklung und Anwendung auf einen Salzdom

Die seismische full-waveform inversion (FWI) genießt in jüngster Zeit wegen ihres hohen Auflösungsvermögens und der Fähigkeit auch hochgradig heterogenen Untergrund aufzulösen immer größere Beliebtheit. Seismische Geschwindigkeitsmodelle können in der Regel zuverlässig bestimmt werden, wohingegen immer noch große Schwierigkeiten bei der Inversion nach der Dichte bestehen. Dies liegt zum einen an der geringen Sensitivität seismischer Wellen in Bezug auf Dichtevariationen und zum anderen an trade-off Effekten zwischen den involvierten Parametern. Außerdem ist die Interpretation der seismischen Amplituden grundsätzlich mehrdeutig, da neben der Dichte auch Effekte wie Dämpfung, Anisotropie und Rauschen eine Rolle spielen. Die klassische Schwereinversion leidet dagegen an inhärenter Mehrdeutigkeit, da die Schwere ein Potentialfeld darstellt, und weist nur eine Auflösbarkeit im langwelligen Bereich auf. Um diese Einschränkungen zu überwinden führen wir eine gemeinsame Inversion von Druckseismogrammen und Schweresignalen durch. Dabei benutzen wir weder empirische Beziehungen noch Kriterien, die auf strukturellen Ähnlichkeiten basieren. Als Testmodell für einen Rekonstruktionstest benutzen wir einen Salzdom, der in einige Sedimentschichten eingebettet ist. Das rekonstruierte Dichtemodell der gemeinsamen Inversion enthält kurzwellige Informationen über die Sedimentschichten, welche nicht in den Resultaten der reinen Schwereinversion enthalten sind. Im Vergleich zu der reinen FWI leidet die gemeinsame Inversion weniger an gegenläufigen Abhängigkeiten zwischen den unterschiedlichen Parametern. Außerdem erklärt das finale Dichtemodell die pseudo-observierten Schweresignale fast perfekt. Dies ist bei der reinen FWI nicht der Fall. Abschließend ist zu sagen, dass die Integration von Schweredaten in der Tat die trade-off Effekte zwischen der P-Wellengeschwindigkeit und der Dichte verringern kann und dass außerdem eine höhere Auflösung des Dichtemodelles im Vergleich zu der reinen Schwereinversion erreichbar ist. Unsere Inversionsstrategie erlaubt es, eine vertrauenswürdigere Interpretation von Dichteverteilungen durchzuführen als es die individuellen Methoden gewährleisten

Shape Bonding method

The present invention is directed to a method of bonding at least two surfaces together. The methods step of the present invention include applying a strip of adhesive to a first surface along a predefined outer boundary of a bond area and thereby defining a remaining open area there within. A second surface, or gusset plate, is affixed onto the adhesive before the adhesive cures. The strip of adhesive is allowed to cure and then a second amount of adhesive is applied to cover the remaining open area and substantially fill a void between said first and second surfaces about said bond area. A stencil may be used to precisely apply the strip of adhesive. When the strip cures, it acts as a dam to prevent overflow of the subsequent application of adhesive to undesired areas. The method results in a precise bond area free of undesired shapes and of a preferred profile which eliminate the drawbacks of the prior art bonds

Femtosecond x-ray absorption spectroscopy of spin and orbital angular momentum in photoexcited Ni films during ultrafast demagnetization

We follow for the first time the evolution of the spin and orbital angular momentum of a thin Ni film during ultrafast demagnetization, by means of x-ray magnetic circular dichroism. Both components decrease with a 130 +/- 40 fs time constant upon excitation with a femtosecond laser pulse. Additional x-ray absorption measurements reveal an increase in the spin-orbit interaction by 6 +/- 2 % during this process. This is the experimental demonstration quantifying the importance of spin-orbit mediated processes during the demagnetization