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There is an attempt to demonstrate that the computation of joint density functions of apparent radiance (as opposed to their direct measurement) is not an unreasonable task.

Initial test results on the experimental tube and associated apparatus are described together with certain changes suggested by the test results. Problems connected with making S-9 photocathodes by the atomic beam cesiation method have delayed angular distributon measurements. A tube is described which was built for experiments to correlate photoelectric properties with impurity concentrations in photocathodes as determined by Hall effect measurements. Certain theoretical aspects of the angular energy distribution are discussed.

A U. S. Coast Guard HC-130B aircraft was flown on a parallel track pattern while within range of a high accuracy tracking radar, and the navigational performance of the aircraft while using only certain specified aids was observed. The aids used were LF and UHF radiobeacons, the aircraft's doppler radar, a transponder for the aircraft's search radar, and an inertial guidance system.

The development and results of tests of 3 different arc configurations are presented. A doublering electrode arc unit, when discharging into the atmosphere, provided 40% utilization of theAVAILABLE ELECTRICAL POWER. This ac arc head was subsequently operated in conjunction with the previously constructed vac um system to establish subatmospheric test conditions in the plasma stream. It was found that this arc configurationvacuum system combination resulted in reduced thermal efficiencies. (Author)

Recent advances in electric are research and development allow stable high-temperature environments to be obtained over extended periods of time in the laboratory. By making use of the known relationships between temperature and conductivity in such are discharges and by experimentally measuring the current density, electron density, and temperature, the effective cross section of atoms which impede the electron flow can be determined. Thus, atom-electron collision cross sections can now be measured in the interesting energy range of 1 to 2 ev, lower than heretofore possible using conventional beam apparatus. Techniques involved in making the necessary spectroscopic and electrical measurements are given, and results obtained for three gases (argon, helium, and nitrogen) are presented. These results are then used to determine several of the transport properties for these partially ionized gases.

Experiments and analyses, emphasizing diagnostics (local temperature distributions), have been applied to cross-flow, axial-flow, and seeded plasma configurations. Application of a unique optical system, which permits radiation from the arc to be observed simultaneously at eleven azimuthal angles about the arc column, has permitted the determination of the local temperature distribution for this non-circular (in cross-section) configuration. High speed data acquisition techniques have been applied to determine the local temperatures during the dynamic response of voltage pulsed axial-flow plasmas. The tests carried out upon the cross-flow arc have also detailed the cross-sectional shape and arc profile.

A number of recent advances in finite element theory and computer technology are combined into a computer program for analyzing structures and cavities in rock. The program applies to general three-dimensional structures, considers nonlinear material properties, including joints, anisotropic and time- dependent material properties, gravity loading and sequence of construction or excavation. The computer program is applied to the analysis of deflections in the back of a chamber which was excavated in argillaceous quartzite at the Caladay Project, Osburn, Idaho. Auxiliary calculations were performed to help develop a viscoelastic model of argillite from in situ measurements. The final, three-dimensional calculation involves excavation and viscoelastic deformation and the results are compared with measurements., See also Volume 2, AD0761649.

The report shows how input is prepared for a computer program for rock-structure interaction., See also Volume 1, AD0761648 and Volume 3, AD0761650.

The computer program of this report is on a seven-track magnetic tape which is unlabeled, even parity, external BCD and is written at 556 BPI. The tape has constant record sizes, each record being 1920 characters long (24-80 column card image per record). An end of file mark follows the last record on the tape. Volume 2 of this report is entitled, 'User's Guide to a Computer Program for Analytic Modeling of Rock-Structure Interaction.' Volume 1, entitled, 'Analytic Modeling of Rock-Structure Interaction,' contains the theoretical basis of the computer programs and applications. Both Volumes are available from DDC-TC and NTIS. (Author), See also Volume 1, AD-761 648, and Volume 2, AD-761 649. INcludes Volume 3, Computer Program, AD-761 650.

A number of recent advances in finite element theory and computer technology are combined into a computer program for analyzing structures and cavities in rock. The program applies to general three-dimensional structures, considers nonlinear material properties, including joints, anisotropic and time- dependent material properties, gravity loading and sequence of construction or excavation. Example problems, demonstrating the ability of the program to reproduce idialized situations having closed-form, analytic solutions are solved.

The results of six sonobuoy wide angle reflection profiles in the Southern Chukchi Sea show that from 200 to 700 meters of unconsolidated sediments with acoustic velocities less than 2 km/sec overlay 1-1 1/2 kilometers of sandstones and shales with velocities in the range of 2.1 to 2.8 km/sec. A higher velocity formation of approximately 4 km/sec was found at two of the six stations. These results show that extensive deposition, as well as marine erosion, has played an important role in making the Chukchi Sea floor the flat feature that it is today. (Author)

The free lateral vibration of a simply-supported metallic beam under axial creep deformation is considered. The constitutive law is formulated with stress power functions in the primary and secondary creep terms; the instantaneous linear elastic deformation is also included. For better physical visualization, a nonlinear Maxwell-Kelvin model is used to represent the constitutive law. A reduction to various special models is also obtained. It is assumed that the initial stress is much greater than the increments of stress caused by the oscillation, and a perturbation technique is employed. In the present study, the perturbation essentially results in replacing a nonlinear viscoelastic problem by an equivalent linear viscoelastic problem. Analytical solutions for the Maxwell-Kelvin model and for the special models are obtained. Numerical results for a stainless steel and an aluminum alloy are also presented and discussed. (Author), Prepared in cooperation with Westinghouse Electric Corp., East Pittsburgh, Pa. and Lockheed Missiles and Space Co., Sunnyvale, Calif.

The report presents a complete description of the programming aspects of the GEOPS program. Written in FORTRAN IV for the IBM-7094 computer, the program utilizes full core storage and ten magnetic tapes during its execution. The glossary of symbols contains all those eimportant to the computational logic. Program flow is described both from an overall and from an individual routine viewpoint. Compilation procedures, computational logic, and input-output specifications are presented. The reader should, at any time, have reference to an actual listing of the program. Two associated, supplementary programs, an equinox tape generator and an input data pre-processor, are also described in this report. (Author)

A detailed mathematical description is presented associated with the computer program which will recursively obtain minimum variance estimates of orbital parameters, geopotential coefficients, station locations, and tracking systems error model coefficients from measurements taken by diverse electronic and optical tracking systems.

The operation of an xisting subatmospheric plasma arc facility was characterized to assist the user in selecting the proper simulation conditions for materials test application. Eight principal test conditions were established within the operating limits of the arc, and the pertinent parameters describing the thermal environment were determined and tabulated. Subsequently, the hypersonic re-entry conditions corresponding to the thermal environment of the test conditions were computed and plotted on a velocity-altitude chart. In addition, an arc unit with water-cooled, non-consumable electrodes was developed to reduce contamination of the arc plasma. This arc, having double-ring electrode configuration, will generate plasma with a net average enthalpy of 8000 Btu/lb. The final phase concerned testing various materials under different exposure conditions. (Author)

The influence of parametric variations of through-flow velocity and of arc current upon the local temperature distribution (and associated cross-sectional shape) of a steady-state, 1.1 atmosphere Argon cross-flow arc have been determined experimentally. Forced convection, at constant current, exerts profound influence upon the plasma. Isotherm distributions, obtained in a horizontal plane 4.94 mm above the anode (electrode spacing = 11.2 mm), indicate the pattern changes from that corresponding to the flow about a heated, blunt body (at low speeds) to that about a heated, highly streamlined body (at high speeds). The cross-section is noncircular, with major axis in the direction of flow. (Author), Sponsored in part by Grants NIH-FR-00126 and NSF-GP-7318. See also report dated May 68, AD-676 041.

Results of time-resolved spectroscopic temperature measurements in small regions of a turbulent laboratory arc plasma generator are described. Techniques and instrumentation for carrying out time-resolved measurements are described. The effects of arc turbulence on apparent spectroscopic temperatures determined by conventional spectroscopic methods are demonstrated. The errors in average temperature measured by conventional spectroscopy as compared with the true average temperature in the same region of the arc determined by timeresolved spectroscopy are appreciable. No simple way was found to find true average temperatures in a turbulent arc plasma from apparent, conventional spectroscopic, average values. (Author)

A radially directed load is suddenly applied to a portion of the outer surface of a circular cylindrical shell which responds in a state of plane strain. An analytical solution for the resulting dynamic response is obtained within the context of linear elasticity theory, Flugge shell theory, and an 'improved' shell theory. A comparison of the analytical solutions and numerical results for a specific loading indicate that the improved theory is far superior to the Flugge Theory in terms of predicting both the magnitude and characteristics of the response. However, as expected, neither shell theory can satisfactorily predict the wave character of the initial response.

The investigation considers axial wave motion in rods of circular cross-section and compares the predictions of elementary rod theory (as characterized by the wave equation) with those of an improved theory which accounts for longitudinal as well as radial motions. Three specific cases are considered in detail: (a) wave motion in two bonded, semi-infinite rods composed of different materials, (b) wave motion in a rod of finite length bonded at each end to two semi-infinite rods composed of a different material, and (c) dynamic response of a rod of finite length, fixed at one end and suddenly loaded at the other end. Considerable differences in the predictions of the two theories are observed under certain conditions. (Author)

The acceleration environment produced by the Western Gear Model 4010 High Amplitude Vibration Machine was surveyed at even fundamental frequencies from 2 to 20 cps at two levels of acceleration, 1 G and 2 G. The frequency components of the motion up to 50 cps were determined by a M-H 9050 Automatic Wave Analyzer and are presented in the form of harmonic distributions for each fundamental. The 'total distortion figure' and 'overall distortion figure' are used as measures of the fidelity with which the acceleration wave approximates a pure sine wave of the fundamental frequency. The data dictated that the 1 G acceleration was more distorted than the 2 G and that at both levels the distortion increased with frequency. (Author)