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Standard

Global eLoran User Equipment Interface Standard

2018-12-18
WIP
SAE1012
There are numerous GNSS user equipment interface standards in use that provide some form of timing and/or positioning information. This document incorporates their essential content into a uniform array that will enable seamless interoperation with eLoran.
Standard

Global eLoran User Equipment Interface Standard for Timing

2019-04-16
WIP
SAE1012/1
There are numerous GNSS user equipment interface standards in use that provide some form of timing and/or positioning information. This document incorporates their essential content into a uniform array that will enable seamless interoperation with eLoran.
Standard

Standard for Interfacing Resilient GNSS Receivers

2019-04-18
WIP
SAE1014
This standard defines how a resilient GNSS receiver provides enough information for an alternative PNT source to be selected when the GNSS receiver does not meet the required levels of accuracy, availability, integrity, or continuity even when the GNSS signals are subject to interference
Technical Paper

Antiwear Properties and Applications of Thin Hard Coatings

1996-04-01
91A106
Different techniques, like PVD, CVD, ion implantation, are increasingly used to produce thin film layers of ceramic compounds to modify the surface properties of metals, carbides, ceramics or polymeric components for specialized conditions or in severe conditions of use. Carbides, nitrides, oxides, etc. have been deposited on the most varied supports to solve problems of high temperature, erosion, corrosion, diffusion and conductivity or electrical resistance. The fields of thin hard coating applications are: tools, dies, punches, mechanical components (for antiwear deposits), structures (for anticorrosion), optics (reflecting or absorbing layers) and microelectronics. In this paper we will present the principal characteristics of different thin hard coating layers and processes, and the principal applications in the anti-wear field.
Technical Paper

Graphitic Foam Thermal Management Materials for Electronic Packaging

2000-04-02
2000-01-1576
The goal of this program is to utilize the recently developed high conductivity carbon foam for thermal management in electronics (heat exchangers and heat sinks). The technique used to fabricate the foam produces mesophase pitch-based graphitic foam with extremely high thermal conductivity and an open-celled structure. The thermal properties of the foam have been increased by 79% from 106 to 187 W/m·K at a density of 0.56 g/cm3 through process optimization. It has been demonstrated that when the high-thermal-conductivity graphitic foam is utilized as the core material for the heat exchanger, the effective heat transfer can be increased by at least an order of magnitude compared to traditional designs. A once-through-foam core/aluminum-plated heat exchanger has been fabricated for testing in electronic modules for power inverters.
Technical Paper

Advanced Lithium Solid State Battery Developments

2000-04-02
2000-01-1588
This paper presents a summary of a recent conference entitled Advanced Lithium Solid State Batteries Workshop that was held on July 13–15, 1999. The conference was sponsored by the Department of Energy's Office of Advanced Automotive Technologies, and the Office of Basic Energy Sciences' (BES) Division of Chemical Sciences. This paper presents a summary of the results and recommendations from the conference, including: A review of current research on solid state electrolytes and their interfaces with an emphasis on both applied and basic studies. The research includes theoretical studies of solid polymer electrolytes (SPEs), lithium ion transport in SPEs, and simulations of the electrolyte–cathode interface. Experimental results are presented on ion transport phenomena in SPEs (NMR and X–ray) and mechanical stresses on electrodes, among other topics.
Technical Paper

The Use of Chemiluminescence for the Ranking of Lubricants in Terms of Oxidation Stability

2000-06-19
2000-01-1812
In this study, a chemiluminescence apparatus (CL), ATLAS CL–400, was employed to measure the oxidation induction time (OIT) of various types of lubricants. Results of OIT obtained for base oils and industrial oils were compared to that obtained from standardized methods requiring larger expenditures of sample and/or analysis time. Some exploratory tests were also run on engine oils having increased expected performance. The technique was found to be very good for the ranking of lubricants since the relative oxidation stability of the products studied has been successfully evaluated by chemiluminescence (CL). This method was shown to be a good tool for oil formulation optimization.
Technical Paper

The Magnesium Hatchback of the 3-Liter Car: Processing and Corrosion Protection

2000-03-06
2000-01-1123
The hatchback of Volkswagen's 3 liter car (3 l fuel consumption per 100 km) consists of an inner component of die casting magnesium (AM50) covered with an aluminum panel from the outside. This hybrid design requires a new manufacturing process: The pre-coated magnesium part will be bonded and folded with the bare aluminum part. Corrosion protection is provided by an organic coating system which both protects against general corrosion and galvanic corrosion. The corrosion of the Al / Mg sandwich has been examined with hybrid samples which are similar to the hatchback. Several powder coatings (epoxy resin, polyester resin, hybrid resin), wet paints and cathodic electro-coating paints of different thicknesses and compositions have been applied to the magnesium part. They show that only powder coating provides adequate protection. Galvanic corrosion at the points of attachment of the hatchback might be possible (for example the bolted joint of the hinge).
Technical Paper

Simulation and Visualization of Some Processes Concerning Gases Transport Properties and Gaseous Fuel Combustion, Starting from the Molecular Collision Theory

2000-03-06
2000-01-1080
Starting from the molecular collision theory, the goals of this study are the simulation and visualization of some processes related to gases transport properties and gaseous fuel combustion, like: formation of Maxwell distribution function, diffusion, thermal diffusion, heat conductivity, heat transfer to the walls, spark ignition, autoignition, wall ignition, laminar flame propagation and two wall quenching. The simulation program replaces the molecules with a certain number of spheres (100-2700). Each specie is simulated with a determined type of sphere characterized by mass, speed, diameter and a specific color for the identification on the screen. The spheres moves inside a two-dimensional space. The collisions between spheres are elastic. The activation energy condition must be achieved during a collision involving two molecules in order to have chemical reaction.
Technical Paper

Thermal Barrier Coatings for Monolithic Ceramic Low Heat Rejection Diesel Engine Components

2000-03-06
2000-01-1236
The future of maintaining a superior mobile military ground vehicle fleet rests in high power density propulsion systems. As the U.S. Government desires to convert its powerplant base to heavy fuel operation, there arises the opportunity to incorporate new advanced materials into these heavy fuel engines. These newer materials serve the purpose of decreasing powerplant weight and develop new component designs to take advantage of improved strength and temperature capability of those materials. In addition, the military continues the effort for a non-watercooled Low Heat Rejection (LHR) diesel engine. This type of engine demands the use of ceramic and advanced ceramic composite material hardware. Furthermore, today's higher pressure fuel injection systems, coupled with reduced air/fuel ratio as a means of increasing horsepower to size and weight, will require thermal protection or change in material specification for many of the engine's components.
Technical Paper

The Determination of Thermal Properties of Engine Combustion Chamber Deposits

2000-03-06
2000-01-1215
Thermal conductivity and thermal diffusivity of combustion chamber deposits in an s. i. engine and a diesel engine were determined by measuring thickness, response time to a radiation pulse, time-varying deposit surface temperature and deposit-wall interface temperature. The results show that, for the s. i. engine deposits formed with a stoichiometric mixture of unleaded gasoline, the thermal conductivity is hardly influenced by engine load, speed and equivalence ratio, and that thermal diffusivity depends on equivalence ratio, but hardly depends on engine load and speed. The test result with unleaded gasoline containing lubricating oil indicates that the thermal properties are sensitive to the lubricating oil content and depend considerably on engine load. The thermal properties of diesel deposit are the first data that have been presented.
Technical Paper

An Overview of the Thermal Verification and Testing of Integral and Artemis Satellites

2000-07-10
2000-01-2497
Integral (INTErnational Gamma Ray Astrophysics Laboratory) is an ESA observatory scientific satellite to be used for gamma ray astronomy, while Artemis (Advanced Relay and TEchnology MISsion) is an ESA program to be used for data relay and technology demonstration. Both programs have been recently submitted to a System Environmental test campaign including extensive Thermal Balance tests with Solar Simulation performed in the Large Solar Simulation (LSS) chamber at ESTEC Noordwijk in 1998. Alenia Spazio, who has the role of Prime Contractor for both programs at Torino and Rome premises respectively for Integral and Artemis, is responsible of the Thermal Control of the satellites and the relevant verification aspects.
Technical Paper

INTEGRAL Spectrometer Thermal Balance Test

2000-07-10
2000-01-2498
This paper describes the thermal balance test which has been performed on the spectrometer SPI Structural and Thermal Model (INTEGRAL project) from August 27th to September 17th 1999. Main SPI modes have been simulated in order to qualify the instrument thermal control. MLI efficiency has been measured, as well as thermal conductance to the payload module (PLM). For this, a specific thermal adaptator (a mechanical frame and two aluminum plates regulated by two cryostats) has been developed and will also be used for thermal vacuum tests of the SPI Flight Model. This thermal adaptator and its behavior during thermal balance test are described.
Technical Paper

Advanced Space Suit Insulation Feasibility Study

2000-07-10
2000-01-2479
For planetary applications, the space suit insulation has unique requirements because it must perform in a dynamic mode to protect humans in the harsh dust, pressure and temperature environments. Since the presence of a gaseous planetary atmosphere adds significant thermal conductance to the suit insulation, the current multi-layer flexible insulation designed for vacuum applications is not suitable in reduced pressure planetary environments such as that of Mars. Therefore a feasibility study has been conducted at NASA to identify the most promising insulation concepts that can be developed to provide an acceptable suit insulation. Insulation concepts surveyed include foams, microspheres, microfibers, and vacuum jackets. The feasibility study includes a literature survey of potential concepts, an evaluation of test results for initial insulation concepts, and a development philosophy to be pursued as a result of the initial testing and conceptual surveys.
Technical Paper

“Derivation of Conduction Heat Transfer in Thin Shell Toroids”

2000-07-10
2000-01-2487
This paper presents the derivation of the equations for circumferential, longitudinal and radial heat transfer conductance for a thin shell toroid or a segment of the toroid. A thin shell toroid is one in which the radius to thickness ratio is greater than 10. The equations for the surface area of a toroid or of a toroidal segment will also be derived along with the equation to determine the location of the centroid. The surface area is needed to determine the radial conductance in the toroid or toroidal segment and the centroid is needed to determine the heat transfer center of the toroid or toroidal segment for circumferential and longitudinal conductance. These equations can be used to obtain more accurate results for conductive heat transfer in toroid which is a curved spacecraft components. A comparison will be made (1) using the equations derived in this paper which takes into account the curvature of the toroid (true geometry) and (2) using flat plates to simulate the toroid.
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