| Cavitation Inception in Separated Flows |
DEC 1981 |
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| Authors:
Joseph Katz; CALIFORNIA INST OF TECH PASADENA
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 | The phenomenon of cavitation was studied on four axisymmetric bodies whose boundary layers underwent a laminar separation and a subsequent turbulent reattachment. The conditions for cavitation inception and desinence were determined and several holograms were recorded just prior to and at the onset of cavitation. The population of microbubbles and the nature of the subsequent development of visible cavitation was determined from the reconstructed image. Cavitation inception occurred in the ... |
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| One-Way Coherent Imaging through a Distorting Medium Using Four-Wave Mixing |
23 NOV 1981 |
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| Authors:
Amnon Yariv; Thomas L. Koch; CALIFORNIA INST OF TECH PASADENA
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| Submicron Systems Architecture Project |
NOV 1981 |
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| Authors:
Charles L. Seitz; Carver A. Mead; Lennart Johnson; Randal Bryant; Jim Kajiya; CALIFORNIA INST OF TECH PASADENA
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| This project is concerned with the architecture, design, and testing of VLSI Systems. The principal activities in this report period include: The Tree Machine; COPE, The Homogeneous Machine; Computational Arrays; Switch-Level Model for MOS Logic Design; Testing; Local Network and Designer Workstations; Self-timed Systems; Characterization of Deadlock Free Resource Contention; Concurrency Algebra; Language Design and Logic for Program Verification. |
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| Electron Hopping versus Molecular Diffusion as Charge Transfer Mechanisms in Redox Polymer Films |
23 SEP 1981 |
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| Authors:
Daniel A. Buttry; Fred C. Anson; CALIFORNIA INST OF TECH PASADENA
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| Bistability and Negative Resistance in Semiconductor Lasers |
08 SEP 1981 |
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| Authors:
Ch. Harder; K. Y. Lau; A. Yariv; CALIFORNIA INST OF TECH PASADENA
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| Demonstration of the Use of VLSI Design Rules, Standards, and Interfaces |
01 SEP 1981 |
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| Authors:
Carver Mead; CALIFORNIA INST OF TECH PASADENA
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| For abstract see AD-A100 583. |
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| Waiting-Time Behavior in a Nonlinear Diffusion Equation |
13 AUG 1981 |
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| Authors:
William L. Kath; Donald S. Cohen; CALIFORNIA INST OF TECH PASADENA
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| Conducting and Magnetic Polymers |
09 AUG 81 |
8 pages |
| Authors:
Robert H. Grubbs; Dennis A. Dougherty; CALIFORNIA INST OF TECH PASADENA
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 | Unsaturated polymeric materials with interesting electronic, optical and magnetic properties are being prepared. The major route to these materials is through the Ring Opening Polymerization (ROMP) of highly unsaturated monomers. The ROMP of substituted cyclooctatetraene and methylenecyclobutenes has been the major route to such materials. Materials with tailored electronic and physical properties have resulted from these studies. A recent development has been the synthesis of a precursor polymer for a ... |
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| Interferometric Microwave Polarimetry as a Tool for Short-Term Solar Flare Prediction |
AUG 1981 |
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| Authors:
G. J. Hurford; CALIFORNIA INST OF TECH PASADENA
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| The purpose of this study is to look at a data base of interferometric solar microwave data in order to identify, evaluate and interpret preflare microwave signatures, with reference to their possible role in the short-term prediction of solar flares. Reserving the second half of this data base for verification of tentative results, 27 major flares were selected using optical, soft x-ray OR microwave flux criteria for which good quality ... |
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| The Application of Ion Implantation to Compound Formation |
JUL 1981 |
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| Authors:
James W. Mayer; Marc-A. Nicolet; J. O. McCaldin; CALIFORNIA INST OF TECH PASADENA
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| Contents: Solid-Phase Epitaxial Growth (SPEG); Radioactive Si Tracer Technique; Redistribution of Impurities in Silicide Formation; Ion Mixing; Very Thin Films, and 400 kV Ion Implantation System. |
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| Propagation of Shock Waves through Nonuniform and Random Media, |
JUL 1981 |
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| Authors:
B. Sturtevant; L. Hesselink; B. S. White; V. Kulkarny; C. Catherasoo; CALIFORNIA INST OF TECH PASADENA
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| A study of the propagation of shock waves through random media, which was described in the 12th International Shock Tube Symposium, has been continued. A diagnostic technique is described in which shadowgraph motion pictures of the plane shock wave can be used to study the changed that occur in the distribution of spatial scales in the medium. The growth of large fluctuations in the amplitude of acoustic shocks has been ... |
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| A Tunable Narrowband Optical Filter via Phase Conjugation by Nondegenerate Four-Wave Mixing in a Doppler-Broadened Resonant Medium |
22 JUN 1981 |
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| Authors:
Joseph Nilsen; Amnon Yariv; CALIFORNIA INST OF TECH PASADENA
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| Bistability and Pulsations in CW Semiconductor Lasers with a Controlled Amount of Saturable Absorption |
15 MAY 1981 |
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| Authors:
Ch. Harder; K. Y. Lau; A. Yariv; CALIFORNIA INST OF TECH PASADENA
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| Submicron Systems Architecture. |
05 May 1981 |
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| Authors:
Charles L Seitz; Carver Mead; CALIFORNIA INST OF TECH PASADENA
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| An assembly language has been defined for the tree machine and its instruction set. The language supports both the notation proposed and used by Sally Browning and the notation proposed and used by Marina Chen in her work on HARMOS. The assembly language contains pseudo instructions for the definition of the interconnections in the logical tree and the logical name of the ports. Macro definition and expansion features are included. ... |
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| Seismic Design of Liquid Storage Tanks |
APR 1981 |
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| Authors:
Medhat A. Haroun; George W. Housner; CALIFORNIA INST OF TECH PASADENA
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| A simple and sufficiently accurate method for estimating the seismic response of cylindrical liquid storage tanks is presented. A mechanical model, which takes into account the deformability of the tank wall is examined; it is based on the results of a finite element analysis of the liquid-shell system. The parameters of such a model are displayed in charts that facilitate the calculations of the effective masses, their centers of gravity, ... |
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| Narrow-Band Optical Filter through Phase Conjugation by Nondegenerate Four-Wave Mixing in Sodium Vapor |
30 MAR 1981 |
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| Authors:
Joseph Nilsen; Natalie S. Gluck; Amnon Yariv; CALIFORNIA INST OF TECH PASADENA
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| Demonstration of the Use of VLSI Design Rules, Standards, and Interfaces |
01 MAR 1981 |
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| Authors:
Carver Mead; CALIFORNIA INST OF TECH PASADENA
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| For complete abstract, see AD-A100 583. |
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| Phonon Reflection at Noble Gas Interfaces, |
Mar 1981 |
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| Authors:
PETER TABOREK; David L Goodstein; CALIFORNIA INST OF TECH PASADENA
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| High resolution phonon reflection spectra from thin films of noble gases condensed onto a sapphire substrate at 2 K are presented. Phonon reflection signals from films of helium, neon, argon, krypton and xenon are found to be essentially identical, suggesting that quantum effects play no role. We argue, however, that the conventional interpretation of a change in the signal as due to heat escaping from the system cannot be valid ... |
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| Experimental Investigation on the Effects of Chemical Heat Release in the Reacting Turbulent Plane Shear Layer |
JAN 1981 |
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| Authors:
A. K. Wallace; CALIFORNIA INST OF TECH PASADENA
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| A chemically reacting shear layer between various gases was investigated in a new type of blow-down wind tunnel. The gas streams were inert (helium, nitrogen or argon), but carried up to 10% concentration of reactants, one being ozone and the other nitric oxide. The resulting reaction, 03 + NO yields N02 + 02, was essentially diffusion limited and spontaneous, enabling the temperature rise to be varied at will from zero ... |
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| High-Resolution Interferometric Spectrophotopolarimetry. |
JAN 1981 |
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| Authors:
A. L. Fymat; CALIFORNIA INST OF TECH PASADENA
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| Charge-Coupled Device (CCD) Trackers for High-Accuracy Guidance Application. |
JAN 1981 |
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| Authors:
P. M. Salomon; CALIFORNIA INST OF TECH PASADENA
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| Two New Bifurcation Phenomena |
1981 |
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| Authors:
Herbert B. Keller; CALIFORNIA INST OF TECH PASADENA
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| Electronic Properties of Heterojunctions |
1981 |
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| Authors:
J. O. McCaldin; T. C. McGill; CALIFORNIA INST OF TECH PASADENA
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| Work under this contract was primarily concerned with experiments on so-called lattice-matched Schottky barrier interfaces and with theory of superlattices. These are both rather idealized cases of semiconductor interfaces, simplifying some of the complexities of the general interfaces and affording new insights. (Author) |
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| THEORETICAL STUDIES OF THE NONLINEAR INFRARED PROPERTIES OF p-TYPE SEMICONDUCTORS. |
1981 |
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| Authors:
R. B. James; CALIFORNIA INST OF TECH PASADENA
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| Demonstration of the Use of VLSI Design Rules, Standards, and Interfaces |
01 DEC 1980 |
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| Authors:
Carver Mead; CALIFORNIA INST OF TECH PASADENA
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| For complete abstract, see AD-A100 583. |
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| Path Following Near Bifurcation. |
Nov-1980 |
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| Authors:
D W Decker; H B keller; CALIFORNIA INST OF TECH PASADENA
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| Demonstration of the Use of VLSI Design Rules, Standards, and Interfaces |
01 SEP 1980 |
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| Authors:
Carver Mead; CALIFORNIA INST OF TECH PASADENA
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| Topics reported include: Task 1--Consultation from fabrication lines, CMOS-SOS and NMOS-Si gate test-chips, Geometrical design rules, Speed and timing rules, and Testability rules; and Task 2--CIF/APPLICON, CALMA conversion software, and Circuit design. |
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| Electromagnetic Propagation in Multimode Optical Fibers, Excited by Sources of Finite Bandwidth. |
15 AUG 1980 |
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| Authors:
C. H. Papas; CALIFORNIA INST OF TECH PASADENA
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| The dependence of the temporal width of the impulse response on the length z of a two-mode optical fiber is examined. This quantity, which is proportional to z in the absence of mode coupling and to z in the presence of weak random coupling among the guided modes, possesses a different dependence in the case of a deterministic resonant-coupling model, appropriate for describing a rather general class of actual situations. ... |
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| improved ultrasonic detection using the analytic signal magnitude |
AUG 80 |
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| Authors:
Paul M. Gammell; CALIFORNIA INST OF TECH PASADENA
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| an alternative to rectification is proposed for detection of an ultrasonic signal for medical or nondestructive evaluation applications. with this technique the envelope of the ultrasonic waveform is obtained by calculation of the magnitude of the complex analytic signal. an implementation, particularly suited for digital data processing, is presented which utilizes a fast fourier transform for computation of the quadrature component of the received signal using the hilbert transform. an ... |
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| Base Isolation for Torsion Reduction in Asymmetric Structures Under Earthquake Loading |
JUL 1980 |
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| Authors:
David M. Lee; CALIFORNIA INST OF TECH PASADENA
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| This paper examines the effectiveness of a bilinear hysteretic base isolation system in lowering the shear forces and torques generated in a structure by two-way, translatory ground motions. The study is restricted to single-story, three-dimensional structures having asymmetries in both horizontal directions and being excited by the El Centro (May 1940) earthquake motions. It is shown that with base isolation the structural torques are drastically reduced, even if the structural ... |
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| Estimating Inelastic Response Spectra From Elastic Spectra |
JUL 1980 |
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| Authors:
W. D. Iwan; CALIFORNIA INST OF TECH PASADENA
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| Inelastic displacement response spectra are determined for a broad class of single-degree-of-freedom hysteretic structures. Based on these spectra, effective linear period and damping parameters are defined as a function of ductility. A simple empirical formula is derived which may be used to estimate the mid-period range inelastic response spectrum of a general hysteretic structure given the linear response spectrum of the excitation. The estimates obtained from this formula are compared ... |
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| On Electromagnetic Waves in Chiral Media |
JUN 1980 |
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| Authors:
D. L. Jaggard; A. R. Mickelson; C. H. Papas; CALIFORNIA INST OF TECH PASADENA
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| The propagation of electromagnetic waves through chiral media, i.e., through composite media consisting of macroscopic chiral objects randomly embedded in a dielectric is analyzed. The peculiar effects that such media have on the polarization properties of the waves are placed in evidence. To demonstrate the physical basis of these effects a specific example, chosen for its analytical simplicity, is worked out from first principles. (Author) |
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| Steady-State and Transient Electromagnetic Coupling through Slabs |
JUN 1980 |
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| Authors:
G. Franceschetti; C. H. Papas; CALIFORNIA INST OF TECH PASADENA
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| The problem of electromagnetic transmission through a slab where transmitting and receiving antennas are at finite distances from the slab is of concern. The mathematical formulation of the problem is quite general. A detailed solution is presented for the case of a highly conducting slap exposed to sinusoidal and transient excitations. A discussion is given of the conditions under which measurements with source and receiver at finite distances are equivalent ... |
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| On the Application of Symmetrization to the Transmission of Electromagnetic Waves through Small Convex Apertures of Arbitrary Shape |
JUN 1980 |
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| Authors:
D. L. Jaggard; C. H. Papas; CALIFORNIA INST OF TECH PASADENA
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| The transmission of an electromagnetic wave through a small aperture in a perfectly conducting screen is examined from the viewpoint of symmetrization. (Author) |
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| Strong Ground Motions for the Homestead Valley, California, Earthquake Inferred From a Water Tank 'Seismoscope' |
MAY 1980 |
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| Authors:
John E. Ebel; Robert L. Hill; James C. Pechmann; CALIFORNIA INST OF TECH PASADENA
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| The water tank 'seismoscope' appears to have left a very complete record of one of the Homestead Valley earthquakes. The scratches made by the tank on its steel pads indicate that most of the movement of the tank was due to an earthquake centered on the portion of the Homestead Valley fault where the maximum surface displacement was found. The seismic moment of this event was 7 x 10 + ... |
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| Visualization of Impact Damage of Composite Plates by Means of the Moire Technique |
APR 80 |
54 pages |
| Authors:
W. G. Knauss; C. D. Babcock; H. Chai; CALIFORNIA INST OF TECH PASADENA
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| The results of a program to determine the phenomenological aspects of the propagation damage due to low velocity impact on heavily loaded graphite- epoxy composite laminates are described. The main tool of this investigation is high speed photography coupled with the moire fringe technique. High speed moire' motion records of the impacted specimens are presented. The test results provide information on the time scale and sequence of the failure process. ... |
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| Visualization of Impact Damage of Composite Plates by Means of the Moire Technique, |
APR 80 |
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| Authors:
W. G. Knauss; C. D. Babcock; H. Chai; CALIFORNIA INST OF TECH PASADENA
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| The results of a program to determine the phenomenological aspects of the propagation damage due to low velocity impact on heavily loaded graphite- epoxy composite laminates are described. The main tool of this investigation is high speed photography coupled with the moire fringe technique. High speed moire motion records of the impacted specimens are presented. The test results provide information on the time scale and sequence of the failure process. ... |
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| Structural Identification Using Linear Models and Earthquake Records |
MAR 1980 |
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| Authors:
James L. Beck; Paul C. Jennings; CALIFORNIA INST OF TECH PASADENA
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| The problem of determining linear models of structures from seismic response data is investigated using ideas from the the theory of system identification. The approach is to determine the optimal estimates of the model parameters by minimizing a selected measure-of-fit between the responses of the structure and the model. Because earthquake records are normally available from only a small number of locations in a structure, and because of noise in ... |
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| Structural Identification in the Frequency Domain from Earthquake Records |
MAR 1980 |
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| Authors:
Graeme H. McVerry; CALIFORNIA INST OF TECH PASADENA
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| A method has been developed to identify the parameters of the lower modes of a linear, time-invariant model of a structure from its recorded earthquake response. The identification is performed by selecting the parameters to obtain a least squares fit over a specified frequency band between the unsmoothed, complex-valued finite Fourier transform of the recorded acceleration response and the corresponding transform calculated from the response of the model. By including ... |
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| Real-Time Image Processing via Four-Wave Mixing in a Photorefractive Medium, |
21 JAN 1980 |
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| Authors:
Jeffrey O. White; Amnon Yariv; CALIFORNIA INST OF TECH PASADENA
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| Polymer Attached Catalysts. |
07 JAN 1980 |
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| Authors:
Robert H. Grubbs ; CALIFORNIA INST OF TECH PASADENA
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| Monomers containing two ligand groups separated by either flat aromatic groups or long alkyl chains were prepared. These materials were use to make polymers in with nickel(II) or phi-rhodium(I) halides were used to link the monomer units. The major part of the study used 1,12-bis(diphenylphosphino)-dodecane as the monomer unit. Polymethylmethacrylate-Pt composites were evaluated as oxidation catalysts and as electrode coatings. (Author) |
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| Use of Thermal-Inertia Properties for Material Identification. |
1980 |
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| Authors:
John P. Schieldge; Anne B. Kahle; Ronald E. Alley; Alan R. Gillespie; CALIFORNIA INST OF TECH PASADENA
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| A knowledge of the thermal inertia of the Earth's surface can be used in geologic mapping as a complement to surface reflectance data as provided by Landsat. Thermal inertia, a body property, cannot be determined directly but can be inferred from radiation temperature measurements made at various times in the diurnal heating cycle, combined with a model of the surface heating processes. We have developed such a model and applied ... |
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| Steady State and RF Properties of Proximity Effect Weak Links. |
20 DEC 1979 |
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| Authors:
R. P. McNamara; J. E. Mercereau; CALIFORNIA INST OF TECH PASADENA
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| A detailed experimental examination of the dc critical supercurrent density, j sub c, and the microwave (nonzero voltage) supercurrent, j sub mu, has been made in proximity effect thin film weak links at temperatures above the transition temperature of the link material. These results were correlated with measured dimensional and superconducting parameters of the thin films and the link via a Ginzberg-Landau (GL) formalism. In the steady state, j sub ... |
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| Structure of a Linear Array of Uniform Vortices |
23 NOV 1979 |
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| Authors:
P. G. Saffman; R. Szeto; CALIFORNIA INST OF TECH PASADENA
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| Base Isolation Systems for Earthquake Protection of Multi-Storey Shear Structures |
NOV 1979 |
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| Authors:
D. M. Lee; I. C. Medland; CALIFORNIA INST OF TECH PASADENA
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| This paper is a study of the effectiveness of a wide range of bilinear hysteretic isolation systems in shielding multi-storey 2-D shear structures from earthquake excitations. Important parameters of the isolation system are identified and their effect on structure response noted. It is shown that isolation systems can be constructed which allow the structure proper to remain purely elastic even during very strong ground motions. It is further shown that ... |
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| Intradune Flats of the Algodones Chain, Imperial Valley, California |
OCT 1979 |
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| Authors:
Robert P. Sharp; CALIFORNIA INST OF TECH PASADENA
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| A striking characteristic of the southeastern part of the remarkably linear northwest-southeast Algodones Dunes chain is a succession of regularly spaced, wholly enclosed flats exposing the alluvial substrate. Each flat is bounded on the northwest by a high active slip face of sand and on the southeast by a more gently inclined deflated sand slope, suggesting that the flats are moving southeasterly along the chain axis. Measurements over a 12-yr ... |
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| The Deployment of Strong-Motion Earthquake Instrument Arrays |
SEP 1979 |
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| Authors:
Wilfred D. Iwan; CALIFORNIA INST OF TECH PASADENA
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| The International Workshop on Strong-motion Earthquake Instrument Arrays was held during 2-5 May 1978 in Honolulu, Hawaii. The goal of the workshop was to develop a workable plan for the possible future deployment of dense strong-motion arrays with primary emphasis on ground motion studies. Topics considered by the workshop included: favourable array locations, the design of arrays for source mechanism and wave propagation studies, the design of arrays for local ... |
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| Leading Edge Flutter of Supercavitating Hydrofoils. |
MAY 1979 |
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| Authors:
C. Brennen; K. Oey; C. D. Babcock; CALIFORNIA INST OF TECH PASADENA
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| This document represents the results of experiments and analysis of the phenomenon of leading edge flutter which has been observed to occur for supercavitating hydrofoils. The experiments confirmed the existence of such a single degree of freedom flutter involving chordwise bending and indicated that for long, natural (or vapor-filled) cavities the reduced flutter speed U sub F/omega sub FC was in the range 0.15 to 0.23. Secondary effects observed were ... |
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| The Effective Period and Damping of a Class of Hysteretic Structures |
MAY 1979 |
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| Authors:
Wilfred D. Iwan; Nathan C. Gates; CALIFORNIA INST OF TECH PASADENA
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| This paper presents the results of a numerical investigation in which the maximum response of 6 hysteretic systems is calculated for an esemble of 12 earthquakes. Inelastic response spectra are constructed for a range of response ductility. An effective linear period and damping are calculated for each system ductility by determining those parameters which minimize an RMS response spectrum error. Conclusions are presented concerning the effects of deterioration, stiffness degradation, ... |
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| A Comparative Mechanophysiological Study of Fish Locomotion with Implications for Tuna-Like Swimming Mode, |
30 MAR 1979 |
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| Authors:
Theodore Y. Wu; George T. Yates; CALIFORNIA INST OF TECH PASADENA
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| An interdisciplinary study is continued to investigate the energetics and hydrodynamics of fish swimming involving transfer of biochemical energy through the rate of muscular working to the final stage of delivering the hydrodynamical power. Comparison between the drag coefficient and the power coefficient available for swimming, converted from data on metabolic rate with estimated muscle efficiency and hydromechanical efficiency, indicates their dependence on the Reynolds number according to a well ... |
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Reports by Corporate Author
