Two notes on perturbation theory. 1 - Interchange theorems and the variation principle. 2 - PV in a different notation
Interchange theorems and variational principle in perturbation theory
Epstein, S. T.↗
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LM and CSM S-band antenna tracking studies. Electronics assembly interchangeability study. Volume 1 - Small signal analysis
Small signal characteristics and estimated limits of interchangeable electronics assembly for Apollo tracking antenna system
Robinson, L. H., Jr.↗
Empirical determination of radiation interchange factors Final report
Techniques for measuring radiant interchange factors relative to spacecraft thermal design
Bobco, R. P.↗
Surface roughness effects on radiant energy interchange
Surface roughness effects on thermal radiant energy interchange between opaque interacting surfaces formulated for unequal temperature adjoint plates
Hering, R. G.↗
Radiation interchange factors Quarterly report, 7 Jun. - 1 Sep. 1968
Empirical and analytical techniques for determining thermal radiation interchange factors
Source record↗
Experimental determination of radiative interchange factors - Analytical basis and exploratory measurements
Total radiative interchange kernel measurements, describing remote excitation/detection
Bobco, R. P.↗
Laboratory method for assessing homogeneity and interchangeability of thermocouple wires
Laboratory method assessing homogeneity and interchangeability of thermocouple wires, considering thermoelectric properties of widely separated wire from same spool
Powell, R. L.↗
Connector interchangeability
The application is discussed of the general rules of ANSI Y14.5 in designing connectors for interchangeability, and lowering costs. The general rules are applied to actural connector designs, and existing specifications are identified that (1) reject better quality products than those accepted, (2) accept products which should be rejected, and (3) impose unnecessary, nonfunctional costly requirements.
Berilla, T.↗
Accretion onto magnetized neutron stars - Structure and interchange instability of a model magnetosphere
A self-consistent model is analyzed for the spherical infall of weakly magnetized plasma into the magnetosphere of a slowly rotating, strongly magnetized neutron star. It is shown that spherical infall is probably a good approximation for X-ray sources which accrete from a stellar wind. The location of the standoff shock which halts the hypersonic infall is estimated along with the emission from the shocked layer. The location of the equilibrium magnetopause and the structure of the magnetic field within it are calculated; it is found that the magnetic poles are true cusps and that the entry of gas due to equilibrium flow across a cusp is almost certainly dominated by the interchange instability near the magnetic equator. The energy principle is applied to derive necessary conditions for the occurrence of this instability. The results indicate that the strong magnetic-pressure gradient stabilizes the gas unless moderately strong radiative cooling takes place and that the cooled plasma enters the magnetosphere as long filaments capable of moving between field lines. The rate at which the equilibrium magnetopause can 'absorb' mass and momentum is derived, the validity of the approximations employed is discussed, and the likely evolution of the sinking filaments is outlined to show that the spatial distribution of the plasma is determined mainly by the dynamics and thermodynamics of the filaments rather than the magnetic-field structure.
Arons, J.↗
Interchangeable spring modules for inertia measurements
Operation of inertia balance is simplified by packaging set of balance springs in interchangeable modules. They are held in place in balance pedestal by just two fasteners, making removal and replacement fast and simple. With them, balance can be readied in less than 15 minutes, in contrast to more than 2 hours by previous method.
Mcnamara, J. W.↗
Simulation and evaluation of the Sh-2F helicopter in a shipboard environment using the interchangeable cab system
The operation of the SH-2F helicopter from the decks of small ships in adverse weather was simulated using a large amplitude vertical motion simulator, a wide angle computer generated imagery visual system, and an interchangeable cab (ICAB). The simulation facility, the mathematical programs, and the validation method used to ensure simulation fidelity are described. The results show the simulator to be a useful tool in simulating the ship-landing problem. Characteristics of the ICAB system and ways in which the simulation can be improved are presented.
Paulk, C. H., Jr.↗
Sample interchange of MST radar data from the Urbana radar
As a first step in interchange of data from the Urbana mesosphere-stratosphere-troposphere (MST) radar, a sample tape has been prepared in 9-track 1600-bpi IBM format. It includes all Urbana data for April 1978 (the first month of operation of the radar). The 300-ft tape contains 260 h of typical mesospheric power and line-of-sight velocity data.
Bowhill, S. A.↗
Interchangeable Tools for Remote Manipulators
Report presents concepts and specifications for set of interchangeable end-effector tools used on remotely operated manipulator to work on satellites in orbit. Tools make urgent repairs, do routine maintenance, transfer fluids, construct and assemble satellites, and deploy and retract appendages. With modifications, tool concepts and systematic approach to tool design applicable to such terrestrial uses as industrial robots, manually operated tools, and safety equipment. Report discusses concept for tool-storage system that holds tools securely when not used but kept accessible to manipulator.
Cody, J. C.↗
Interchange of electronic design through VHDL and EIS
The need for both robust and unambiguous electronic designs is a direct requirement of the astonishing growth in design and manufacturing capability during recent years. In order to manage the plethora of designs, and have the design data both interchangeable and interoperable, the Very High Speed Integrated Circuits (VHSIC) program is developing two major standards for the electronic design community. The VHSIC Hardware Description Language (VHDL) is designed to be the lingua franca for transmission of design data between designers and their environments. The Engineering Information System (EIS) is designed to ease the integration of data betweeen diverse design automation systems. This paper describes the rationale for the necessity for these two standards and how they provide a synergistic expressive capability across the macrocosm of design environments.
Wallace, Richard M.↗
The nonlinear breakup of a magnetic layer - Instability to interchange modes
Motivated by considerations of the solar toroidal magnetic field, the behavior of a layer of uniform magnetic field embedded in a convectively stable atmosphere is studied. Since the field can support extra mass, such a configuration is top-heavy and thus instabilities of the Rayleigh-Taylor type can occur. For both static and rotating basic states, the evolution of the interchange modes (no bending of the field lines) is followed by integrating numerically the nonlinear compressible MHD equations. The initial Rayleigh-Taylor instability of the magnetic field gives rise to strong shearing motions, thereby exciting secondary Kelvin-Helmholtz instabilities which wrap the gas into regions of intense vorticity. The subsequent motions are determined primarily by the strong interactions between vortices which are responsible for the rapid disruption of the magnetic layer.
Cattaneo, F.↗
Peripheral Equipment Interchanges Bytes Of Data
Method for conversion of data formats between incompatible computers reduces conversion time by 80 percent. Transposes high and low bytes of word so data from computer A match storage format of computer B. Two interface circuit boards convert data. Such boards ordinarily used for communication between computers. In format-conversion application, cable connecting boards modified so high-8-bit and low-8-bit data lines interchanged with result data words in proper format for computer B.
Aguilar, Robert B.↗
Interchangeable end effector tools utilized on the protoflight manipulator arm
A subset of teleoperator and effector tools was designed, fabricated, delivered and successfully demonstrated on the Marshall Space Flight Center (MSFC) protoflight manipulator arm (PFMA). The tools delivered included a rotary power tool with interchangeable collets and two fluid coupling mate/demate tools; one for a Fairchild coupling and the other for a Purolator coupling. An electrical interface connector was also provided for the rotary power tool. A tool set, from which the subset was selected, for performing on-orbit satellite maintenance was identified and conceptionally designed. Maintenance requirements were synthesized, evaluated and prioritized to develop design requirements for a set of end effector tools representative of those needed to provide on-orbit maintenance of satellites to be flown in the 1986 to 2000 timeframe.
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Directory interchange format manual, version 3.0
The Directory Interchange Format (DIF) is a data structure used to exchange directory level information about data sets among information systems. The format consists of a number of fields that describe the attributes of a directory entry and text blocks that contain a descriptive summary of and references for the directory entry. All fields and the summary are preceded by labels identifying their contents. All values are ASCII character strings. The structure is intended to be flexible, allowing for future changes in the contents of directory entries.
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