A Comparison of Photointerpretive and Digital Production Methods for Four Key Remote Sensing-Based Information Products

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Evaluating Teaching Ability Through the Use of Student Questionnaires

At present there are three general methods of measuring teaching ability. The oldest method is the subjective scheme, whereby certain individuals rate teachers according to their own impressions of the teaching situation. With the introduction of objective testing techniques, the teacher was judged in still another way, that is by the measure of residual gain of the students. At present the most practical method is the combination of the subjective and objective methods. ..

Efficacy of various waveforms to support geolocation

This thesis investigates the impact of various waveform parameters on the ability to estimate accurately the position of the source of a known data-less emission that is visible to multiple simultaneous collectors. It provides an overview of the basic geolocation problem and identifies various parameters affecting geolocation accuracy, showing those that are affected by the waveform and those that are not. Performance estimates are provided for detecting the signal and for estimating the time and frequency of arrival (TOA and FOA) of the signal, which are the key measure of a waveform's ability to support geolocation. Several exemplar waveforms are chosen to illustrate the effects of various waveform parameters, and the performance of these example waveforms is verified through software simulations. Results show for additive white Gaussian noise (AWGN) interference that accuracy of estimates is predominantly determined by the transmit power (i.e., received SNR), signal bandwidth (for TOA), and signal duration (for FOA). For a given SNR, occupied bandwidth, and total duration, a waveform can be "shaped" in the time and frequency domains to improve performance relative to a reference direct sequence spread spectrum (DSSS) signal. Software simulations confirm theoretical performance estimates. This thesis summarizes the effects of various waveform parameters on geolocation performance, demonstrates these by modeling exemplar waveforms, and provides software that can be used to simulate performance.http://archive.org/details/efficacyofvariou109454754Naval Research Laboratory, Washington, D.C. author (civilian).Approved for public release; distribution is unlimited

Systems analysis for the development of small resource recovery systems: research and development needs. Final report

The technologies that should be developed to make small-scale solid waste processing facilities attractive and viable for small municipalities with solid waste between 50 and 250 tons per day are identified. Research and development needs for refuse derived fuel systems, thermal systems, and biological processes are listed. Selected research and development needs discussed for mechanical processing systems are: develop data bank for low-cost, low-energy shredder options; develop performance data for shredders applied after separation; develop data bank for Trommel performance; and identification and evaluation of low-cost materials separation equipment. Selected research and development needs discussed for thermal systems are: emission levels from solid/waste/to/energy systems; determination of the theoretical efficiencies for thermal processing systems; boiler erosion/corrosion evaluation for systems firing refuse derived fuel; optimization of feed and ash handling systems; refractory life and maintenance requirements; development of 5- to 20-TPD systems; and optimization studies of control systems for small modular incinerators. Selected research and development needs discussed for biological processing systems are: optimum design and operation to maximize gas recovery rates and investigate process configuration alternatives for anaerobic digesters

Systems analysis for the development of small resource recovery systems: description of solid waste modular simulator. Final report

The technologies that should be developed to make small-scale solid waste processing facilities attractive and viable for small municipalities with solid waste between 50 and 250 tons per day are identified. The resource recovery systems investigated were divided into three categories: mechanical separation, thermal and thermochemical energy recovery, and bioconversion processes. This report describes the Solid Waste Modular Simulator (SWIMS), a computer program for simulating the performance of solid waste processing/resource recovery systems. The current program data enables the simulation of systems with design throughput rates of 100 and 200 TPD of solid waste. Systems with larger throughput capacities can also be simulated by supplying the program with their performance data. The main line of this program is basicaly an accounting routine which totals the costs, revenues, and mass balances for all components in a simulated waste processing line. In addition, the main line controls the input of all information required to execute the program and the output of the resultant system performance data. (MCW