2,514 research outputs found
MEASURING QUALITY OBJECTIVELY AND NONDESTRUCTIVELY
Discusses the various tests currently used to measure quality of fruits and vegetables.Agribusiness,
The far field diffraction pattern for corner reflectors with complex reflection coefficients
The far field diffraction pattern of a geometrically perfect corner reflector is examined analytically for normally incident monochromatic light. The states of polarization and the complex amplitudes of the emerging light are expressed through transformation matrices in terms of those of the original incident light for each sextant of the face in a single coordinate system. The analytic expression of the total diffraction pattern is obtained for a circular face. This expression consists of three component functions in addition to the basic Airy function. The coefficient of each function is expressed in terms of complex coefficients of reflectance of the reflecting surface. Some numerical results for different reflecting surfaces, including total internal reflection, are presented. The iso-intensity contours of the diffraction pattern evaluated from the analytical expressions for an uncoated solid corner reflector are also presented along with the photographs of the pattern
Geologic application of thermal inertia imaging using HCMM data
Three test sites in the western US were selected to discriminate among surface geologic materials on the basis of their thermal properties as determined from HCMM data. Attempts to determine quantitatively accurate thermal inertia values from HCMM digital data met with only partial success due to the effects of sensor miscalibrations, radiative transfer in the atmosphere, and varying meteorology and elevation across a scene. In most instances, apparent thermal inertia was found to be an excellent qualitative representation of true thermal inertia. Computer processing of digital day and night HCMM data allowed construction of geologically useful images. At some test sites, more information was provided by data than LANDSAT data. Soil moisture effects and differences in spectrally dark materials were more effectively displayed using the thermal data
Cosmological test of the Yilmaz theory of gravity
We test the Yilmaz theory of gravitation by working out the corresponding
Friedmann-type equations generated by assuming the Friedmann-Robertson-Walker
cosmological metrics. In the case that space is flat the theory is consistent
only with either a completely empty universe or a negative energy vacuum that
decays to produce a constant density of matter. In both cases the total energy
remains zero at all times, and in the latter case the acceleration of the
expansion is always negative. To obtain a more flexible and potentially more
realistic cosmology, the equation of state relating the pressure and energy
density of the matter creation process must be different from the vacuum, as
for example is the case in the steady-state models of Gold, Bondi, Hoyle and
others. The theory does not support the cosmological principle for curved space
K =/= 0 cosmological metrics
Manufacture of cream cheese involving the use of dry skim milk
Caption title.Digitized 2006 AES MoU
Evaluation of thermal data for geologic applications
Sensitivity studies using thermal models indicated sources of errors in the determination of thermal inertia from HCMM data. Apparent thermal inertia, with only simple atmospheric radiance corrections to the measured surface temperature, would be sufficient for most operational requirements for surface thermal inertia. Thermal data does have additional information about the nature of surface material that is not available in visible and near infrared reflectance data. Color composites of daytime temperature, nighttime temperature, and albedo were often more useful than thermal inertia images alone for discrimination of lithologic boundaries. A modeling study, using the annual heating cycle, indicated the feasibility of looking for geologic features buried under as much as a meter of alluvial material. The spatial resolution of HCMM data is a major limiting factor in the usefulness of the data for geologic applications. Future thermal infrared satellite sensors should provide spatial resolution comparable to that of the LANDSAT data
In-flight radiometric calibration of the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS)
A reflectance-based method was used to provide an analysis of the in-flight radiometric performance of AVIRIS. Field spectral reflectance measurements of the surface and extinction measurements of the atmosphere using solar radiation were used as input to atmospheric radiative transfer calculations. Five separate codes were used in the analysis. Four include multiple scattering, and the computed radiances from these for flight conditions were in good agreement. Code-generated radiances were compared with AVIRIS-predicted radiances based on two laboratory calibrations (pre- and post-season of flight) for a uniform highly reflecting natural dry lake target. For one spectrometer (C), the pre- and post-season calibration factors were found to give identical results, and to be in agreement with the atmospheric models that include multiple scattering. This positive result validates the field and laboratory calibration technique. Results for the other spectrometers (A, B and D) were widely at variance with the models no matter which calibration factors were used. Potential causes of these discrepancies are discussed
The relation of dry skim milk to several of the physical and chemical properties of cream cheese
Publication authorized June 28, 1934."The data presented in this bulletin were taken from a paper submitted by the junior author in partial fulfillment of the requirements for the degree of Master of Arts in the Graduate School of the University of Missouri, 1933"--P. [3].Includes bibliographical references (page 40)
Pharmacokinetics and tumor dynamics of the nanoparticle IT-101 from PET imaging and tumor histological measurements
IT-101, a cyclodextrin polymer-based nanoparticle containing camptothecin, is in clinical development for the treatment of cancer. Multiorgan pharmacokinetics and accumulation in tumor tissue of IT-101 is investigated by using PET. IT-101 is modified through the attachment of a 1,4,7,10-tetraazacyclododecane-1,4,7-Tris-acetic acid ligand to bind ^(64)Cu^(2+). This modification does not affect the particle size and minimally affects the surface charge of the resulting nanoparticles. PET data from ^(64)Cu-labeled IT-101 are used to quantify the in vivo biodistribution in mice bearing Neuro2A s.c. tumors. The ^(64)Cu-labeled IT-101 displays a biphasic plasma elimination. Approximately 8% of the injected dose is rapidly cleared as a low-molecular-weight fraction through the kidneys. The remaining material circulates in plasma with a terminal half-life of 13.3 h. Steadily increasing concentrations, up to 11% injected dose per cm^3, are observed in the tumor over 24 h, higher than any other tissue at that time. A 3-compartment model is used to determine vascular permeability and nanoparticle retention in tumors, and is able to accurately represent the experimental data. The calculated tumor vascular permeability indicates that the majority of nanoparticles stay intact in circulation and do not disassemble into individual polymer strands. A key assumption to modeling the tumor dynamics is that there is a “sink” for the nanoparticles within the tumor. Histological measurements using confocal microscopy show that IT-101 localizes within tumor cells and provides the sink in the tumor for the nanoparticles
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