LANDSAT-4 thematic mapper Modulation Transfer Function (MTF) evaluation

A power spectrum (PS) analysis technique was used to compare thematic mapper (TM) A and P-tape data for a Washington, DC scene in two orthogonal directions, along scan and along track. The resulting effective modulation transfer functions (MTF) between the A and P data are repeatable from area to area and consistent with theoretical expectations. The average x-direction (along scan) MTF calculated with the PS technique is compared to the MTF of the cubic convolution resampling function used to create P data from A data. The two curves are nearly identical, indicating that the major factor affecting the image quality of P data relative to A data is the cubic convolution resampling

LANDSAT-4 Thematic Mapper Modulation Transfer Function (MTF) evaluation

The Modulation Transfer Function (MTF) for thematic mapping (TM) bands 3, 4, 5 and 7 is reliably estimated with the San Mateo Bridge target in the 12/31/82 scene. These results are to be compared with those from the 8/12/83 scene. Bands 1, 2 and 6 are to be analyzed with a different target possessing greater contrast. This may be possible with the underflight data comparison currently underway. The registration of this data to the TM image of 8/12/83 for a region arround the Stockton sewage pond east of San Francisco has begun. This particular approach has the advantage that the full two-dimensional MFT will be measured instead of the MFT in only one azimuth as reported

MTF analysis of LANDSAT-4 Thematic Mapper

The spatial radiance distribution of a ground target must be known to a resolution at least four to five times greater than that of the system under test when measuring a satellite sensor's modulation transfer function. Calibration of the target requires either the use of man-made special purpose targets with known properties, e.g., a small reflective mirror or a dark-light linear pattern such as line or edge, or use of relatively high resolution underflight imagery to calibrate an arbitrary ground scene. Both approaches are to be used in addition a technique that utilizes an analytical model for the scene spatial frequency power spectrum is being investigated as an alternative to calibration of the scene

Multispectral Resource Sampler (MPS): Proof of Concept. Literature survey of atmospheric corrections

Work done in combining spectral bands to reduce atmospheric effects on spectral signatures is described. The development of atmospheric models and their use with ground and aerial measurements in correcting spectral signatures is reviewed. An overview of studies of atmospheric effects on the accuracy of scene classification is provided

A study of the energy loss spectra induced by impact of 23-125 keV protons on helium atoms

Results of a study of the inelastic energy loss spectra induced by the impact of protons on gaseous helium at energies of 25 to 125 keV are reported. The spectra were obtained by sending an accelerated beam of protons through a chamber containing the helium target gas, mass-analyzing the forward-scattered beam, then decelerating the beam to a low, well-defined energy for energy analysis and detection. The accelerating potential was varied to produce the spectra. An energy resolution of 2 eV was obtained. Apparent differential cross sections and absolute total cross sections were obtained from the spectra. Total cross sections for the sum of the 1¹S-2¹P excitations in the helium atom are reported, along with estimates of the relative contributions of each. Total ionization cross sections, total cross sections for inelastic scattering, apparent energy distributions of ejected electrons, and partial ionic stopping powers are also reported. The excitation cross sections show excellent agreement with recent calculations on the coupled-state approximation, but show little or no agreement with calculations on the distortion and first Born approximations. No other experimental data on these excitation cross sections are available for comparison. The ionization cross sections show good agreement with results obtained by other methods and show fair agreement with the first Born approximation at high impact energies. The apparent energy distributions of ejected electrons fall below the results of direct measurements and show poor agreement with the available Born and classical theories. The total cross sections for inelastic scattering show agreement with theory similar to that found in the case of ionization. No other experimental data on total inelastic cross sections are reported in the literature. The partial ionic stopping powers fall below the total stopping powers, the differences increasing at lower impact energies, whee charge exchange is more probable. This behavior is consistent with the difference in definition of the two quantities --Abstract, pages ii-iii

Evaluation of ERTS-1 image sensor spatial resolution in photographic form

There are no author-identified significant results in this report

Apollo 9 multiband photography experiment 5065 Interim post-flight calibration report

Camera and filter postflight spectrum analysis for Apollo 9 multiband photography experimen

Montana Canvas Tent Structure Design

Montana Canvas is one of the premier tent building companies in the world. Their product line includes backcountry tents, wall tents, and large scale shipping tarps. Currently they are looking to expand their product line to include large party tents of up to 60’ in width. Eric Schowengerdt and Nick Morales, both Mechanical Engineering students at Montana Tech, have both designed fixtures and verified several of the fixtures already in use by Montana Canvas. These fixtures were put through finite element analysis on a computer and many static hand calculations, which simulated the loading on them from 120 mph to 85 mph wind conditions. This report will outline the processes used to determine the max loading area, alternative solutions to the structure, and finite element analysis on the structure

Energy-loss Spectra And Collision Cross Sections For Impact Of 20-120-keV Positive Ions On Molecular Nitrogen

Inelastic energy-loss spectra induced by impact of H+, H2+, and Ar+ on N2 have been measured at incident ion energies of 20-120 keV, with an energy resolution of about 2 eV. Prominent peaks are observed at energy losses of 9.5 and 13.8 eV. The first of these is well resolved and is attributed to excitation of the Lyman-Birge-Hopfield (LBH) system of N2. The peak at 13.8 eV is believed due primarily to excitation of the bu1 band of the Worley-Jenkins series. The locations of these features on the energy-loss scale do not agree with results of the electron impact work of others and, in general, show trends with projectile velocity that are consistent with an assumed enhancement of excitation to higher vibrational states with the heavier particles. Collision cross sections for excitation of the two peaks are presented, as well as the total ionization cross section and the cross section for total inelastic processes in the case of proton impact. © 1970 The American Physical Society

A Heavy-ion Energy Loss Spectrometer

A high-resolution system for the measurement of the energy loss spectra of 20-250 keV heavy ions incident on gas targets is described. The high resolution is obtained by decelerating the ion beam to a low, well-defined energy before performing the energy analysis. The energy loss spectrum is determined by changing the accelerator energy to compensate for energy lost in collisions with the gas atoms. The system is arranged so that normal fluctuations in the accelerator\u27s power supply do not affect the energy resolution. The resolving power of the system is 2.5x104. The primary proton beam has a detected WHM of 2 V at 50 kV. An energy loss spectrum is shown for which the collision-excited 11S-21P transition in helium is clearly resolved. © 1969 The American Institute of Physics