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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 199 records · Page 11
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Solar permitting, inspection, and interconnection cycletimes and requirements

Twenty three small-to-large residential, commercial, and industrial PV installers submitted project-level data for analysis, which included timestamps for major components of the permitting, inspection, and interconnection process as well as contract and installation dates. NREL calculated median timelines for these processes across the authorities having jurisdiction (AHJs) and utilities represented in the data. Also included are relevant permitting requirements for AHJs and interconnection process requirements for utilities. This dataset represents the underlying results shown in the Solar Time-based Residential Analytics and Cycle time Estimator (SolarTRACE) viewer. This dataset has been reviewed but errors may exist, and it may not be comprehensive. Errors in the sources (e.g., AHJ permitting requirements lists from data partners) may be duplicated in the dataset.

14 SOLAR ENERGY↗
NASA NTRS1972

Interconnections for fluidic circuits

Circuit elements are grouped on functional basis in rectangular two-dimensional planar arrays or modules. Another interconnection method brings all connections out to module edge. For smaller fluidic circuits, manifold and interconnections are fabricated as single blocks. Advantages of methods are given.

Mangion, C.↗
NASA NTRS1972

Manufacture and quality control of interconnecting wire hardnesses, Volume 1

A standard is presented for manufacture, installation, and quality control of eight types of interconnecting wire harnesses. The processes, process controls, and inspection and test requirements reflected are based on acknowledgment of harness design requirements, acknowledgment of harness installation requirements, identification of the various parts, materials, etc., utilized in harness manufacture, and formulation of a typical manufacturing flow diagram for identification of each manufacturing and quality control process, operation, inspection, and test. The document covers interconnecting wire harnesses defined in the design standard, including type 1, enclosed in fluorocarbon elastomer convolute, tubing; type 2, enclosed in TFE convolute tubing lines with fiberglass braid; type 3, enclosed in TFE convolute tubing; and type 5, combination of types 3 and 4. Knowledge gained through experience on the Saturn 5 program coupled with recent advances in techniques, materials, and processes was incorporated.

Source record↗
NASA NTRS1972

Development of automatic through-insulation welding for microelectric interconnections

The capability to automatically route, remove insulation from, and weld small-diameter solid conductor wire is presented. This would facilitate the economical small-quantity production of complex miniature electronic assemblies. An engineering model of equipment having this capability was developed and evaluated. Whereas early work in the use of welded magnet wire interconnections was concentrated on opposed electrode systems, and generally used heat to melt the wire insulation, the present method is based on a concentric electrode system and a wire feed system which splits the insulation by application of pressure prior to welding. The work deals with the design, fabrication, and evaluation testing of an improved version of this concentric electrode system. Two different approaches to feeding the wire to the concentric electrodes were investigated. It was concluded that the process is feasible for the interconnection of complex miniature electronic assemblies.

Arnett, J. C.↗
NASA NTRS1974

Solar cell welded interconnection development program

Parallel gap welding and ultrasonic bonding techniques were developed for joining selected interconnect materials (silver, aluminum, copper, silver plated molybdenum and Kovar) to silver-titanium and aluminum contact cells. All process variables have been evaluated leading to establishment of optimum solar cell, interconnect, electrodes and equipment criteria for obtainment of consistent high quality welds. Applicability of nondestructive testing of solar cell welds has been studied. A pre-weld monitoring system is being built and will be utilized in the numerically controlled parallel gap weld station.

Katzeff, J. S.↗
NASA NTRS1976

Stability of interconnected dynamical systems described on Banach spaces

New stability results for a large class of interconnected dynamical systems (also called composite systems or large scale systems) described on Banach spaces are established. In the present approach, the objective is always the same: to analyze large scale systems in terms of their lower order and simpler subsystems and in terms of their interconnecting structure. The present results provide a systematic procedure of analyzing hybrid dynamical systems (i.e., systems that are described by a mixture of different types of equations). To demonstrate the method of analysis advanced, two specific examples are considered.

Rasmussen, R. D.↗
NASA NTRS1981

Panel C report: Standards needed for the use of ISO Open Systems Interconnection - basic reference model

The use of an International Standards Organization (ISO) Open Systems Interconnection (OSI) Reference Model and its relevance to interconnecting an Applications Data Service (ADS) pilot program for data sharing is discussed. A top level mapping between the conjectured ADS requirements and identified layers within the OSI Reference Model was performed. It was concluded that the OSI model represents an orderly architecture for the ADS networking planning and that the protocols being developed by the National Bureau of Standards offer the best available implementation approach.

Source record↗
NASA NTRS1982

Method for sequentially processing a multi-level interconnect circuit in a vacuum chamber

The processing of wafer devices to form multilevel interconnects for microelectronic circuits is described. The method is directed to performing the sequential steps of etching the via, removing the photo resist pattern, back sputtering the entire wafer surface and depositing the next layer of interconnect material under common vacuum conditions without exposure to atmospheric conditions. Apparatus for performing the method includes a vacuum system having a vacuum chamber in which wafers are processed on rotating turntables. The vacuum chamber is provided with an RF sputtering system and a DC magnetron sputtering system. A gas inlet is provided in the chamber for the introduction of various gases to the vacuum chamber and the creation of various gas plasma during the sputtering steps.

Routh, D. E.↗
NASA NTRS1984

Monolithic microwave integrated circuits: Interconnections and packaging considerations

Monolithic microwave integrated circuits (MMIC's) above 18 GHz were developed because of important potential system benefits in cost reliability, reproducibility, and control of circuit parameters. The importance of interconnection and packaging techniques that do not compromise these MMIC virtues is emphasized. Currently available microwave transmission media are evaluated to determine their suitability for MMIC interconnections. An antipodal finline type of microstrip waveguide transition's performance is presented. Packaging requirements for MMIC's are discussed for thermal, mechanical, and electrical parameters for optimum desired performance.

Bhasin, K. B.↗
NASA NTRS1984

Effect of Interfacial characteristics of metal clad polymeric substrates on electrical high frequency interconnection performance

Etched metallic conductor lines on metal clad polymeric substrates are used for electronic component interconnections. Significant signal losses are observed for microstrip conductor lines used for interconnecting high frequency devices. At these frequencies, the electronic signal travels closer to the metal-polymer interface due to the skin effect. Copper-teflon interfaces were characterized by scanning electron microscopy (SEM) and Auger electron spectroscopy (AES) to determine the interfacial properties. Data relating roughness of the copper film to signal losses was compared to theory. Films used to enhance adhesion are found, to contribute to these losses.

Bhasin, K. B.↗
NASA NTRS1987

Rupture testing for the quality control of electrodeposited copper interconnections in high-speed, high-density circuits

Printed Wiring Multilayer Board (PWMLB) structures for high speed, high density circuits are prone to failure due to the microcracking of electrolytic copper interconnections. The failure can occur in the foil that makes up the inner layer traces or in the plated through holes (PTH) deposit that forms the layer to layer interconnections. It is shown that there are some distinctive differences in the quality of Type E copper and that these differences can be detected before its use in a PWMLB. It is suggested that the strength of some Type E copper can be very low when the material is hot and that it is the use of this poor quality material in a PWMLB that results in PTH and inner layer microcracking. Since the PWMLB failure in question are induced by a thermal stress, and since the poorer grades of Type E materials used in these structures are susceptible to premature failure under thermal stress, the use of elevated temperature rupture and creep rupture testing is proposed as a means for screening copper foil, or its PTH equivalent, in order to eliminate the problem of Type E copper microcracking in advanced PWMLBs.

Zakraysek, Louis↗
NASA NTRS1987

A covariance analysis algorithm for interconnected systems

A covariance analysis algorithm for propagation of signal statistics in arbitrarily interconnected nonlinear systems is presented which is applied to six-degree-of-freedom systems. The algorithm uses statistical linearization theory to linearize the nonlinear subsystems, and the resulting linearized subsystems are considered in the original interconnection framework for propagation of the signal statistics. Some nonlinearities commonly encountered in six-degree-of-freedom space-vehicle models are referred to in order to illustrate the limitations of this method, along with problems not encountered in standard deterministic simulation analysis. Moreover, the performance of the algorithm shall be numerically exhibited by comparing results using such techniques to Monte Carlo analysis results, both applied to a simple two-dimensional space-intercept problem.

Cheng, Victor H. L.↗
NASA NTRS1987

Open System Interconnection - NASA program communications of the future

Open Systems Interconnection (OSI) standards are being developed by the ISO and the Consultative Committee on International Telephone and Telegraph with the support of industry. These standards are being developed to allow the interconnecting of computer systems and the interworking of applications such that the applications can be independent of any equipment manufacturer. Significant progress has been made, and the establishment of government OSI standards is being considered. There is considerable interest within NASA in the potential benefits of OSI and in communications standards in general. The OSI standards are being considered for possible application in the Space Station onboard data management system. The OSI standards have reached a high level of maturity, and it is now imperative that NASA plan for future migration to OSI where appropriate.

Brady, Charles D.↗
NASA NTRS1988

Surface emitting lasers for optical circuitry - Optical interconnect technology

Surface emitting (SE) lasers and their application in VLSI optical interconnect networks are considered. In particular, the advantages provided by SE lasers in optical interconnect circuits and monolithic integration are discussed. Some of the requirements, such as wavelength stability, power dissipation, emission angle, size, etc., are compared with respect to conventional laser diodes. It is noted that the operation of SE lasers will be critically dependent on the properties of the feedback reflectors. Experimental measurements of reflection spectra on AlGaAs/GaAs multilayer reflectors and InAlAs/InGaAs etalons formed with molecular beam epitaxy (MBE) are presented.

Yu, P. K. L.↗
NASA NTRS1989

Hybrid interconnection structures for real-time parallel processing

The use of hybrid interconnection structures that combine link connections and bus connections for real-time parallel processing is discussed. Idealistic parallel computation models for two real-time computing applications are described with attention given to a tightly coupled network model for object tracking and a network model for image processing. Consideration is given to the following different interconnection structures: the crossbar, the hypercube, the circular linked array, and the bus array.

Kim, K. H.↗
NASA NTRS1991

Five-Segment Interconnection For Electromigration Tests

Proposed integrated-circuit conductive pattern intended for use in electromigration lifetime testing of interconnection lines of integrated circuits. Designed for collection of statistics on electromigration from smallest possible area. Includes 5 interconnection segments with Kelvin voltage taps, with total of 12 contact pads, and provides for simultaneous measurements on all of segments. Attempts to minimize thermal gradients within each segment and conforms to guidelines on electromigration test structures promulgated by National Institute of Standards and Technology (NIST).

Hannaman, David J.↗
NASA NTRS1992

Comparative evaluation of optical waveguides as alternative interconnections for high performance packaging

A detailed comparison between optical and electrical interconnections is presented, with emphasis on advantages and drawbacks of optical link utilization. The impact of attenuation, dispersive degradation, and fan out on signal integrity is discussed. Reflections from discontinuities are taken into account in the section on fan out. According to our results, there is no obvious advantage of using optical interconnections for the distribution of digital signals containing significant frequency components in excess of 10 GHz, unless substantial distances are involved, for which low dispersion optical waveguides could provide a solution. The implementation of a polyimide optical waveguide in the MCNC package is discussed.

Schacham, S. E.↗