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Functional forms specifying the diffusion characteristics for turbulent flow in the atmosphere are developed, based on the similarity theory of the surface boundary layer. Descriptors of concentration and vertical spread for a continuous point source near the earth's surface are developed. Comparison to other treatises and to observational data both support the approach and confirm the accuracy of the method taken herein. (Author)

A lightweight half megawatt average power pulse forming network (PFN) designed a store 4 kilojoules (kJ) at 40 kilovolts has been developed. The energy storage system produces a 10 microsecond pulse at a repetition rate of 125 hertz and has a one ohm impedance. It is designed to operate adiabatically for durations of 60 seconds. A lifetime capability of over 400,000 pulses has been demonstrated. (Author)

A solar power radiacmeter (breadboard) design is described, based on a miniature (18 cc) ionization chamber and low power, solid-state (Field Effect Transistor, FET) electrometer. Power demand for this instrument, including DC converter, is approximately 5 mW. Preliminary experiments with a 20 sq cm silicon solar cell panel and pen light (AA size) rechargeable (NiCd) battery suggest feasibility of this approach. Solar power intake and dissipation is discussed for experiments conducted. (Author)

The procedure and theory for determining wind profiles from radiance measurements obtained by vertical temperature profile sounders on polar orbiting meteorological satellites are presented. The use of the wind profiles from 15 to 30 km altitude in the generation of nuclear fallout prediction on the battlefield is discussed. Comparisons of winds obtained with this technique with profiles obtained from radiosonde measurements have been made for 33 sets of data. Results of these comparisons indicate that the winds derived from radiance measurements are sufficiently accurate to satisfy the Army's requirements for wind data, in the 15 to 30 km altitude range, for nuclear fallout prediction. (Author)

This report describes the mathematical information, input data, and results of a methodology and two life-cycle requirements models for comparing computer architectures with respect to life-cycle costs: the Top Down (TD) model and the Bottom-Up (BU) model. The methodology and models were formulated to help the Army and Navy select a single computer architecture for a software-compatible family of military computers for the 1980's. Three candidate architectures were compared: The IBM System/370, the Digital Equipment Corporation PDP-11, and the Interdata 8/32., See also Volume 8, AD-A049 485.

One of the primary reasons for adopting the architecture of an existing successful computer family as the architecture for a future Military Computer Family is the potential utility of the existing support software base. As such, the evaluation of the amount of support software for each of the three finalist architectures was deemed to constitute a very important factor in the overall selection process. This paper details the software evaluation process utilized as well as the quantitative results of that process. (Author), See also Volume 6, AD-A049 487.

This volume presents the evaluation of the Computer Family Architecture (CFA) candidate machines via a set of test programs. The measures used to rank the computer architectures were S, the size of the test program, and M and R, two measures designed to estimate the principle components contributing to the nominal execution speed of the architecture. The S, M, and R measurements are discussed in detail in this report, but the following numbers are the most important, summary results of our evaluation process. These results are the composite performance of the candidate architectures for the set of 12 test programs specified by the CFA committee. Each test program was coded from two to four times on each architecture to minimize the effect of programmer variability. Analysis of Variance procedure was used to determine the overall relative performance of the three computer architectures., See also Volume 4, AD-A049 483.

Within the period September 1968 to September 1975, six balloon-borne experiments were conducted under the title of 'STRATospheric COMPosition (STRATCOM) Experiments.' The initial experiments (September 1968 and September 1969) were designed to measure the temperature variation near an altitude of 50 km that were to be associated with the diurnal stratospheric tide. Requirements by the Department of Defense for information concerning stratospheric composition, as well as measurements of national interest to the possible pollution of the stratosphere by the Super Sonic Transport and by chlorofluorocarbons, gradually increased the number, types, and complexity of measurements conducted during each successive experiment. This composite report presents, in one publication, the related results obtained from the various experiments comprising the STRATCOM VI-A and VI-B payloads as determined by the various experimenters. The results, coupled with the ECOM Report 'Correlation of Selected Atmospheric Composition Parameters for the Mid-Latitude September Stratosphere,' are representative of the correlated multi-instrument approach of the STRATCOM Program to the experimental study of the stratosphere, backed by chemical kenetic theory and atmospheric modeling.

Accurate predictive models are required for design, testing, and field use of high energy laser systems. The success of these models for transmission predictions including linear and nonlinear effects is made possible only by the availability of a good atmospheric parameter data base which must include turbulence, crosswind, gaseous absorption, and aerosol extinction. A review is given herein of the status of this data base for White Sands Missile Range, the effects recent measurements made by the Atmospheric Sciences Laboratory have on high energy laser transmission predictions, and facility capabilities available with plans to resolve remaining problem areas. (Author) No attempt is made to select the best laser source, but several effects are discussed which may have direct bearing on such a choice. (Author)

The Defense Civil Preparedness Agency (DCPA) has a requirement for a shelter dosimeter, a standby instrument for monitoring gamma ray doses in the event of an atomic war or a nuclear disaster. Its most important requirement is dependability without reliance on external components such as power sources. Radiation-induced darkening of optical fiber has been utilized to construct such a dosimeter in which the dose dependent darkening of glass fibers is read visually by means of a dose-calibrated gray scale. (Author)

Two sound ranging algorithms are examined by observing their behavior in a basic controlled environment. The consistency of both is verified under a variety of meteorological regimes and a selection of arrival time accuracies. The advantages and shortcomings of each are discussed. In particular, possible compromise between timing accuracy and integrity of meteorological data is evidenced. Field applicability may prove feasible. (Author)

Powders composed of spheroidal particles 0.5-0.6 micrometer average size have been synthesized by rapidly quenching melts in the system lithium carbonate-boron oxide-iron oxide. The flow characteristics of the powders are adequate to fabricate Li-ferrite ceramic bodies by arc-plasma-spraying (APS) the powders. Post annealing leads to densification and grain growth with concomitant decrease in coercive force and increase in magnetization and remanence. Inversions in x-ray diffraction line intensity disappears with APS and annealing, yielding expected cation distribution. The inadvertent introduction of zinc accounts for the observed inverse relationship between magnetic moment and Curie temperature. The synthetic powder process requires further refinement to improve powder flow characteristics. (Author), Presented at the Annual Conference on Magnetism and Magnetic Materials (23rd) 8-11 Nov 77, Minneapolis, MN.

The Computer Family Architecture (CFA) Selection Committee was formed to evaluate computer architecture candidates for the purpose of selecting one as the basis for a family of software-compatible military computers. The military spends billions yearly for developing computer systems for tactical and strategic applications. The proliferation of incompatible computer instruction sets aggravates the problems of software development maintenance, documentation and training. A demonstrated approach to mitigating this problem is for the military to adopt a well-known, proven instruction-set architecture which can be implemented in advanced technologies as a family of software-compatible computers. Important benefits of this approach include open competition among military computer vendors to build CFA computers using their own hardware production techniques and the availability of a large, mature set of software development tools and associated programmer expertise. In pursuit of the CFA goals, a joint Army/Navy effort instituted to select a CFA and develop a Military Computer Family (MCF) using the CFA. An Army/Navy Selection Committee representing 10 Army and 17 Navy organizations was formed to evaluate and select architectures for the CFA. The CFA Selection Committee Final Report (Volumes II through IX) describes the work of the Selection Committee performed over the period October 1975 through August 1976. (Author), See also Volume 2, AD-A049 457.

This investigation describes analytical and experimental results obtained on a C-band ferrite limiter which utilizes a YIG rod inserted along the longitudinal axis of a coupled dielectric resonator bandpass structure. This device is aimed at providing receiver front-end protection for communication systems such as the AN/GRC-144 which operate in a dense, high signal power environment. By utilizing a long, thin, single crystal YIG rod instead of YIG spheres, the limiter dynamic range has been extended from 20 dB to 35 dB. The threshold power varies from 5 dBm at 4.4 GHz to 15 dBm at 5.0 GHz with an insertion loss of less than 1.0 dB across the band. (Author)

The emission properties of thin film tin-oxide cold cathodes are reported. Indications of the relative effect of doping concentrations and thickness on emission properties are also included. Empirical analysis of the emission data is made and utilized to indicate the possible emission mechanism. Based on the results obtained during the course of this study, comments are given on this emitter's potential as a practical cold cathode for low and medium power microwave tubes. (Author)

An Army/Navy Computer Family Architecture (CFA) Selection Committee, comprising ten Army and seventeen Navy Organizations was organized by the Naval Research Laboratory and the Army Electronics Command in 1975 to select a proven, well-known computer architecture to be the basis of a Military Computer Family (MCF). The Selection Committee met five times in the period between October, 1975, and August, 1976 and evaluated nine computer architecture candidates in accordance with criteria established by the Committee. The Committee applied a preliminary screening process to select three candidates (IBM S/370, DEC PDP-11, and Inter-data 8/32) for more intensive evaluation. This final evaluation process considered experimentally determined architectural efficiency, support software availability, life cycle cost, and architecture licensing. As a result of this process, the Committee ranked the three architecture finalists., See also rept. no. ECOM-4526 dated Aug 77, AD-A049 468.

The Computer Family Architecture (CFA) final selection process was divided into four phases: (1) Data Review. Data developed by the CFA Selection Committee in connection with initial absolute/quantitative criteria, architecture test results, support software evaluation, licensing terms/conditions and life cycle cost analyses were reviewed and summarized. (2) Manufacturer's Presentation. Representatives of each finalist were invited to give brief presentations about future plans for their architecture. Questions from the Committee probed areas of concern. (3) Discussion. The discussion centered around contributing factors, both pro and con, to the selection of each architecture. (4) Summation. Each Architecture Subcommittee chairman provided a summation of the case for selection of his architecture., See also Volume 9, AD-A049 486.

This volume describes the process of automatically gathering architectural data from the benchmark programs. Formal descriptions of the candidate architectures were written and run under a simulator. Assembly listings of the benchmark programs were used to generate simulation command files containing absolute code. These command files were then used to initialize the simulated memory. The result of the simulated benchmarks were collected into a data base for post-processing. Automating the data collection process not only eliminated tedious and potentially error prone hand calculations, but also provided the means to gather dynamic program behavior information that would be almost impossible to calculate manually. (Author), See also Volume 5, AD-A049 484.

The selection of initial candidate computer architectures to be evaluated by the CFA Committee was begun with letters from NRL and ECOM to 21 Navy and 15 Army commands, laboratories, system centers, and project managers, soliciting proposals for candidates architectures. These inquiries were followed by discussions at the first two CFA meetings and resulted in an initial set of nine computer architectures: (1) AN/GYK-12, (2) AN/UYK-7, (3) AN/UYK-20, (4) Burroughs 6700, (5) Data General NOVA (ROLM-1664), (6) IBM System/370, (7) DEC PDP-11, (8) SEL 32, and (9) Interdata 8/32. In order to begin the evaluation process and reduce the number of candidate architectures for more intensive examination and benchmarking, a set of absolute and quantitative criteria were developed. The result of this initial ranking and screening process was to narrow the list of candidates to three machines., See also Volume 3, AD-A049 482.

This volume describes various issues confronted by the Computer Family Architecture (CFA) Selection Committee in its search for a standard military computer architecture. This discussion of issues reveals the difficult nature of the Committee's task. Further, it demonstrates the sources of the Committee's confidence in its final recommendations. The motivation for including this data in the final Committee report derives from the Committee's experience in bringing new Committee members 'up to speed' and in describing progress to non-participants. Invariably, newcomers raised questions with which the Committee had already dealt at length. Eleven issues of premise and thirteen issues of procedure are discussed in detail. Each issue is presented as a question. Its significance is discussed and the impact of the Committee's decision relevant to the issue is described. The decision of the Committee is stated and supporting rationale provided. (Author), See also Volume 1, AD-A049 468.

The utility of thermal winds computed from satellite thermal sounder observations is investigated. The investigation is in terms of the downrange distance and radial lines used for construction of nuclear fallout predictions. Empirical estimates of the accuracies of these quantities are obtained by comparisons with the same quantities determined from radiosonde data. Sixty sets of colocated satellite and radiosonde observations were used in these evaluations. For each comparison, corresponding fallout predictions were computed for a range of assumed nuclear yields between 100 kilotons and 5 megatons. Thermal winds derived from the satellite data were used at the upper altitude. Tie-on altitudes of 15 and 10 km were used. RMS differences between the predictands derived from the two methods of determining winds yielded values of less than 5 degrees for the radial lines and less than 3 percent for the downrange distance when the 15 km tie-on was used. When the 10 km values were used for tie-on, RMS values for radial line differences varied from 3 to 9.5 degrees, while those for downrange distance varied between 0 and 7.5 percent.

The frequency- or immittance-temperature anomalies occurring in quartz crystal resonators are called activity dips. Testing for their presence can represent a considerable addition to the manufacturing cost. An electronic method is described that is rapid, simple, and well adapted to microprocessor control. It makes use of the fact that the desired mode of vibration is shifted in frequency by a variable series capacitor, while interfering modes that cause activity dips are nearly unaffected. (Author)

A simple procedure is presented for normalizing satellite spectral radiance measurements taken at zenith angle theta to corresponding values which would have been observed at zero zenith angle. From simulated data for the DMSP SSH sounder, it is shown that the variation of observed radiance with zenith angle is approximately linear when taken as a function of the square root of the secant of the angle. This relationship is employed to develop the correction formula. (Author)

Field testing of hermetic and plastic encapsulated semiconductors has shown that ceramic dual-in-line packages (DIP) are superior than most plastic packages. Hermetic flat packs, however, are poorer than most plastic packages and a device fabricated with a trimetal interconnection metallization and an epoxy novolac encapsulant can be as good as ceramic DIPs. Silicone encapsulated devices are usually the poorest performers. Devices tested in the storage condition have, in some cases, poorer results than their equivalent, which have been biased. This can be attributed to reduction of the relative humidity at the chip surface due to a higher temperature produced by the power dissipation of the device. In general, in this field test program, plastic devices have not performed as poorly as had been expected. Newer devices, which include CMOS circuits and integrated circuits fabricated with various tape-chip carrier processes, are beginning evaluation. Results from tests on these units will be a good yard stick in assessing the reliability of semiconductors in the future.

Excess time delays of transionospheric radio signals introduce ranging errors in satellite-navigation and radar systems, which are directly proportional to the total electron content (tec) along the propagation path. Correlations of TEC values (based on linear regression analysis) at Fort Monmouth, NJ (40.18 deg. N, 74.06 deg. W) Richmond, FL (25.60 deg. N, 80.40 deg. W) were previously determined. The correlation analysis was performed at monthly and daily intervals for winter periods during the quiet phase of the solar cycle.

The feasibility of constructing a single integrated functional device in a dielectric waveguide cavity has been demonstrated. This device is a self-oscillating mixer and antenna consisting of a negative resistance diode imbedded in a high-resistivity dielectric such as silicon or Al2O3, with one end of the resonant cavity tapered. This taper serves as an antenna or a coupling element into a standard metal waveguide. Tests have been made at Ku-Band and at V-Band, and it has been found that when used as a receiver, the overall noise figure is in the order of 10 to 12 dB, including the IF amplifiers. These receivers also provide large bandwidths. The device is simple in construction which predicts low cost and ease in manufacturing. Applications are suggested based on noise figures, minimum detectable sensitivities, and RF power capabilities for systems requiring small size and low cost. These include communications, expendable Electronic Warfare (EW) sensors, radar and short-range terminal homing. These devices may lead to future developments in low-cost millimeter-wave integrated circuits in which entire sections of precision machined metal waveguide structures are eliminated. (Author)

The conditions of formation from the oxides of single crystal and polycrystal-line cerium magnesium aluminate have been established. The fluorescence spectra of these compounds in the near ultraviolet and the quantum efficiency of the conversion of 200-300 nm radiation have been measured. The possibility of using cerium magnesium aluminate in polycrystalline and single crystal configurations in a personal radiation detector is discussed. (Author)

AT-cut quartz plate resonators are usually edge mounted. For precision applications, and especially where ruggedness is required, a four-point mount is necessary. This report investigates those mounts consisting of two pairs of diametric attachments. For this class of mount a locus is found for the angles of attachment of the circular plate with respect to the crystallographic axes such that radially directed edge forces are compensated. One point on the locus is found to be particularly frequency insensitive to mounting errors, and defines the optimum setting for the four-point mount. (Author)

The discharge, gain and oscillator characteristics of transversely excited CO2 gas mixes was investigated under pulsed and CW conditions. A 1.6 mm square channel having a segmented upper electrode structure and a solid copper electrode with dielectric sidewalls formed the discharge chamber. Resistive loading of the individual discharge segments precluded arcing and insured glow discharges. However, the discharges were not wall confined except at pressures below 100 Torr, thereby reducing wall cooling and complete volumetric excitation. For low pressures a large fraction of the energy was deposited in the cathode fall region. At higher pressures the luminous glow discharge column narrowed and the ratio of the power dissipated in the cathode fall region decreased. However, the total power and power densities deposited in this region increased. The high electric fields and gas temperatures in this region dissociate and ionize molecules thereby limiting sealed-off lifetimes. Diffusion of heat into the adjoining gas creates turbulence and limits the gain. Detailed analysis of the negative aspects of the cathode fall region and nonuniform volume excitation suggests those areas where improvement is most essential. Certain improvements can be obtained by revising the construction of these devices. It remains essential, however, to limit the negative aspects of the cathode fall region and the Malter effect is suggested as one possible means of accomplishing this. (Author)

The Obukhov dynamic similarity of flows hypothesis for the surface boundary layer of the atmosphere has been reevaluated with respect to an arbitrary variable rather than a constant in the diabatic influence function. A literature search revealed that estimates of the so-called constant beta ranged from 0.6 beta 17, suggesting that beta was indeed a variable. Analysis of 103 wind and temperature profiles extracted from the literature led to the conclusion that no constant exists for the log plus linear profile form for thermally stratified stable flow and that the critical value of the gradient Richardson number is unity. (Author)

Contents: Nonlinear Stress/Strain Phenomena, Resonator Design and Measurement, Crystal Filters and Material Properties, Theory and Design of Resonators (Including Quartz Watch Crystals), Resonator Processing Techniques, Frequency Generation and Measurement, Surface Wave Devices, Frequency and Time - Synchronization, Distribution and Application, Remote Synchronization, Atomic and Molecular Frequency Standards.

Precision frequency control requirements for future digital communication systems require improved crystal resonator performance in a number of aspects. Accordingly, the potential of doubly rotated quartz cuts has begun to be explored. In the neighborhood of the SC-cut (YX omega L) phi/theta, phi approximately equals 21.9 degrees, theta approximately equals +33.9 degrees, a variety of effects having their bases in nonlinear elasticity have been shown, or are predicted, to be improved with respect to corresponding AT-cut values. The static frequency-temperature behavior also shows improvement. This report concerns the force-frequency effect, thus far not investigated in any detail for doubly rotated quartz plate vibrators. It relates initial stress produced by mounting supports to resonance frequency changes; it contributes to long-term aging, and is related to the frequency excursions produced in shock and vibration environments. In-plane diametric forces applied to the periphery of vibrating plates produce frequency changes that depend upon the azimuth angle psi in the plane of the plate. For the IT-cut at phi = 19.1 degrees, the maximum value was found previously to be only about one-third that of the AT-cut. This points to a reduced coefficient at the SC-cut as well. Measurements of the force-frequency effect coefficients have now been extended to doubly rotated quartz plates. Also given are charts of the mode spectra in the region of the thickness modes, and the modal temperature coefficients.

A fabrication facility for the preparation of Trichloroethylene/Oxide (TCE/O2) over the temperature range of 850 C - 1200 C is described. The TCE/02 oxide films obtained were of good quality, and uniform in the thickness range of 150-1500 angstrom. Electrical parameters such as Qss and Qo, were found to be at acceptable levels communsurate with values normally obtained in hydrochloric acid grown oxides or ultra-clean thermally grown oxides. (Author)

A magnesium/manganese dioxide cell has been developed for direct heating of field rations under short-circuit conditions. Although fast and convenient, the cell has the disadvantage of producing considerable hydrogen gas during its operation, thereby presenting a potential explosion hazard. This report deals with an electrochemical analysis of the hydrogen evolution problem in the magnesium/manganese dioxide heater cell and with the exploration of aluminum alloys as low-gassing substitutes for magnesium in such a cell. The results reveal that, in the early period of discharge of a magnesium cell, most of the hydrogen is produced at the anode. Gas production becomes more significant at the cathode during the latter period of cell discharge. The use of an aluminum alloy anode of a particular composition greatly reduces the problem of gassing at the anode and completely eliminated gassing at the cathode. (Author)

The imaginary part of the complex compliance matrix, denoted as the fluency, is defined, and the elements are computed for alpha-quartz. Its application to low frequency vibrators is discussed. The role of motional time constants in characterizing resonator behavior is also described and applied to the minus 18.5 degree bar. (Author)

Arc plasma spray techniques have previously been developed for fabricating low microwave frequency non-reciprocal ferrite phase shifters, 3 GHz to 6 GHz. Currently, spraying techniques are being developed for the arc plasma fabrication of ferrite phasers for millimeter frequencies 35 GHz to 95 GHz. It is expected that the arc plasma process will have a significant impact on the cost of millimeter phasors, since they are difficult and expensive to fabricate by conventional techniques. Also, arc plasma millimeter phasors are expected to produce an improved device performance. However, for the arc plasma process to be suitable for fabricating millimeter phasors, new techniques and modifications of arc plasma spraying procedures were required. This report presents the techniques developed and the device performance of arc plasma fabrication 35 GHz non-reciprocal ferrite phasors. Projected costs and future fabrication concepts are also presented. (Author)

This report is concerned with the development of data generating programs and analytical models to facilitate the structural analysis of antenna mast and tower structures subjected to static and dynamic loadings. The programs generate the data cards necessary to define the structure geometry and material properties of typical masts and towers for the NASA Structural Analysis Program (NASTRAN). The automatic data generating program for masts can be used to model any mast of constant cross section and can handle any number of cable tie points and anchor points; deform cards to duplicate cable pretension are also generated as well as the force cards needed for representing a uniform wind type pressure. The automatic data generator for towers generates a series of tower stages and considers four (4) variations of tower geometry, three (3) possible base conditions and any number of sides greater than two (2). This program was designed for towers with regular generation properties and equal side lengths, but a separate program enables some variations in side length to be considered. In order to provide an economical but efficient NASTRAN model for analyzing antenna towers, three models, with varying degrees of exactness were investigated using several NASTRAN rigid formats for analysis. The capabilities and limitations of these models, with respect to the rigid formats considered, was studied. (Author)