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This SAE Standard specifies a message set, and its data frames and data elements specifically for use by applications intended to utilize the 5.9 GHz Dedicated Short Range Communications for Wireless Access in Vehicular Environments (DSRC/WAVE, referenced in this document simply as “DSRC”), communications systems. Although the scope of this Standard is focused on DSRC, this message set, and its data frames and data elements have been designed, to the extent possible, to also be of potential use for applications that may be deployed in conjunction with other wireless communications technologies. This Standard therefore specifies the definitive message structure and provides sufficient background information to allow readers to properly interpret the message definitions from the point of view of an application developer implementing the messages according to the DSRC Standards.

The 2018 Ultimate GD&T Pocket Guide explains the most common rules, symbols, and concepts used in geometric dimensioning and tolerancing. This one-of-a-kind reference guide includes more than 100 detailed examples to illustrate concepts. Numerous charts for quick reference provide explanations of each GD&T symbol, modifier, and more. This valuable on-the-job resource clarifies how to interpret standard-compliant technical drawings that use ASME Y14.5-2018.

The term “3 inch ice shapes” has assumed numerous definitions throughout the years. At times it has been used to generally characterize large glaze ice accretions on the major aerodynamic surfaces (wing, horizontal stabilizer, vertical stabilizer) for evaluating aerodynamic performance and handling qualities after a prolonged icing encounter. It has also been used as a more direct criterion while determining or enforcing sectional ice shape characteristics such as the maximum pinnacle height. It is the authors’ observation that over the years, the interpretation and application of this term has evolved and is now broadly misunderstood. Compounding the situation is, at present, a seemingly contradictory set of guidance among (and even within) the various international regulatory agencies resulting in an ambiguous set of expectations for design and certification specialists.

Accurate measurement of countersinks in curved parts has always been a challenge. The countersink reference is defined relative to the panel surface which includes some degree of curvature. This curvature thus makes accurate measurements very difficult using both contact and 2D non-contact measurements. By utilizing structured light 3D vision technologies, the ability to very accurately measure a countersink to small tolerances can be achieved. By knowing the pose of the camera and projector, triangulation can be used to calculate the distance to thousands of points on the panel and countersink surface. The plane of the panel is then calculated using Random Sample Consensus (RANSAC) method from the dataset of points which can be adjusted to account for panel curvatures. The countersink is then found using a similar RANSAC method.

This work describes the definition and implementation of a dedicated system (hardware and software) for the quantitative evaluation of the anthropometrics and morphological parameters of the back shape. This was applied to the digital 3D analysis of subjects affected by spinal pathologies. In fact in clinical practice it is needed to have a repeatable and easy method to frequent non invasive screening of the rib system records a 3D model of the back shape standard and automated procedure. Its clinical validation is presented.

This SAE Recommended Practice which defines the terms and tabulates the limits of the characteristics for various protective devices used in conjunction with 400-cycle ground power for civil aircraft is intended to assist the airlines in standardizing on 400-cycle protective systems. The limits found to be acceptable in the civil aircraft industry are presented.

This SAE Standard specifies the test methods, dimensions, and requirements for single core 60 V cables intended for use in road vehicle applications where the nominal system voltage ≤60 V DC (25 V AC). It also specifies additional test methods and/or requirements for 600 V cables intended for use in road vehicle applications where the nominal system voltage is >60 V DC (25 V AC) to ≤600 V DC (600 V AC). Where practical, this standard uses ISO 6722 for test methods, dimensions, and requirements. This standard covers ISO conductor sizes which usually differ from SAE conductor sizes. It also covers the individual cores in multicore cables. See ISO 6722 for “Temperature Class Ratings”.

This Standard specifies the test methods, dimensions, and requirements for single-core 60 V cables intended for use in road vehicle applications where the nominal system voltage ≤ 60 V DC (25 V AC). It also specifies additional test methods and/or requirements for 600 V cables intended for use in road vehicle applications where the nominal system voltage is > 60 V DC (25 V AC) to ≤ 600 V DC (600 V AC). Where practical, this standard uses ISO 6722 for test methods, dimensions, and requirements. This standard covers ISO conductor sizes which usually differ from SAE conductor sizes. It also covers the individual cores in multi-core cables. See ISO 6722 for “Temperature Class Ratings”.

The trend of the 2 wheel vehicle obliges to define accurate methodology for analysing each aspect of the vehicle design. The paper will present the definition process of simple, easy to reproduce, cheap tests for the Electric System, and for the components of it, describing the obtainable results. It will be presented which tests are significant, and which variable must acquired, and the method for organizing the data according to the desired study target aim. As example of the System Approach is proposed the analysis of the Electric Generator Power Unit, it will be presented and described the reason why it could be convenient to install a Lundell Generator.

Nowadays quasi-3D approaches are included in many commercial and research 1D numerical codes, in order to increase their simulation accuracy in presence of complex shape 3D volumes, e.g. plenums and silencers. In particular, these are regarded as valuable approaches for application during the design phase of an engine, for their capability of predicting non-planar waves motion and, on the other hand, for their low requirements in terms of computational runtime. However, the generation of a high-quality quasi-3D computational grid is not always straightforward, especially in case of complex elements, and can be a time-consuming operation, making the quasi-3D tool a less attractive option. In this work, a quasi-3D module has been implemented on the basis of the open-source CFD code OpenFOAM and coupled with the 1D code GASDYN.

Within the frame of a series of initiatives aimed at improving effectiveness of its aircraft design and analysis capabilities, the Military Division of Daimler-Benz Aerospace (Dasa) is developing MIDAS, a multidisciplinary integration framework for a suite of numerical codes suitable to quickly and still accurately assess aircraft performance. As MIDAS specifically targets support of configurational studies in a Conceptual and Preliminary Design environment, peculiar requirements such as scope, range of applicability, and robustness of the system components, reliability of results, care-free operability, and fast response times have to be properly addressed.

A process for simultaneously optimizing the mechanical performance and minimizing the weight of an automotive body-in-white will be developed herein. The process begins with appropriate load path definition though calculation of an optimized topology. Load paths are then converted to sheet metal, and initial critical cross sections are sized and shaped based on packaging, engineering judgment, and stress and stiffness approximations. As a general direction of design, section requirements are based on an overall vehicle “design for stiffness first” philosophy. Design for impact and durability requirements, which generally call for strength rather than stiffness, are then addressed by judicious application of the most recently developed automotive grade advanced high strength steels. Sheet metal gages, including tailored blanks design, are selected via experience and topometry optimization studies.

Airline tenants at Dallas/Fort Worth International Airport (DFW Airport) use deicing/anti-icing chemicals, as may be needed, to maintain wintertime operations. DFW Airport has implemented best management practices for pollution prevention measures relating to deicing/anti-icing activities. However, as the planes leave the deicing pads, deicing/anti-icing fluids can drip from the planes onto the runways, taxiways, and ramp areas. As planes take off, the fluids can also shear off onto Airport property. During winter storm events, these deicing/anti-icing fluids are flushed off the runways, etc., with the stormwater. Stormwater containing deicing/anti-icing fluids can discharge through outfalls into Trigg Lake located in the southwestern part of the DFW Airport property.

The results of an empirical study comparing the deceleration performance characteristics of several passenger cars is presented. Three definitions of average coefficient of friction are developed and utilized as a basis for comparison of the performance of the vehicles. In addition, the percent energy dissipation before skid mark initiation for each vehicle is also presented and compared. The interpretation of skid marks utilizing a site specific skid test with a dissimilar vehicle is then discussed from the perspective of accident reconstruction.

Combustion in modern spark-ignition (SI) engines is increasingly knock-limited with the wide adoption of downsizing and turbocharging technologies. Fuel autoignition conditions are different in these engines compared to the standard Research Octane Number (RON) and Motor Octane Numbers (MON) tests. The Octane Index, OI = RON - K(RON-MON), has been proposed as a means to characterize the actual fuel anti-knock performance in modern engines. The K-factor, by definition equal to 0 and 1 for the RON and MON tests respectively, is intended to characterize the deviation of modern engine operation from these standard octane tests. Accurate knowledge of K is of central importance to the OI model; however, a single method for determining K has not been well accepted in the literature.

Camera sensors that are made of silicon photodiodes and used in ordinary digital cameras are sensitive to visible as well as Near-Infrared (NIR) wavelength. However, since the human vision is sensitive only in the visible region, a hot mirror/infrared blocking filter is used in cameras. Certain complimentary attributes of NIR data are, therefore, lost in this process of image acquisition. However, RGB and NIR images are captured entirely in two different spectra/wavelengths; thus they retain different information. Since NIR and RGB images compromise complimentary information, we believe that this can be exploited for extracting better features, localization of objects of interest and in multi-modal fusion. In this paper, an attempt is made to estimate the NIR image from a given optical image. Using a normal optical camera and based on the compressed sensing framework, the NIR data estimation is formulated as an image recovery problem.

An Ideal Adiabatic analysis of a Stirling cryocooler with multiple expansion stages has been presented previously. In this analysis the compression space and the various expansion spaces are adiabatic, the heat exchangers are isothermal and the regenerators are ideal. This paper is an extension of that analysis to evaluate the enthalpy losses associated with the interstage regenerators. The regenerator effectiveness is defined in terms of the total unidirectional heat flow from the regenerator matrix to the working gas. A new definition of regenerator figure-of-merit is proposed for the intermediate expansion stages based on a stage energy balance, and its evaluation and uses in design are discussed. The analysis of a typical three expansion stage cryocooler is presented.

An optimization technique has been developed on the Flight Design System (FDS) which examines available target and instrument constraints to determine an optimal target launch time for maximum instrument viewing in a cooperative launch scenario. By definition, a cooperative launch is a coordinated mission between an orbiting viewing instrument and a target which is launched from the ground at a time specified by instrument viewing requirements. The technique is designed to evaluate instrument constraints such as range and slewing rate limitations and analyze them parametrically with the relative target launch time to determine the effect on the instrument viewing period. Using the FDS, this technique can be utilized in a real-time situation by updating the instrument's position and re-evaluating applicable parameters to obtain an updated target launch time.

This work aims to introduce a multiaxial fatigue criterion for hard metals. The model is based on the definition of a fatigue damage operator, which contains information on the fatigue solicitation provided by the stress history. Numerical aspects associated with the determination of such fatigue damage operator are presented. An assessment of the proposed fatigue model shows that the predictions obtained are in good agreement with experimental results published in the literature for a number of different materials.

Throughout the manned-space programs of the National Aeronautics and Space Administration (NASA), significant data has been gathered regarding how humans live and work in the environment encountered in space. Recording operational experience helps avoid duplication of errors, can improve the design of equipment and procedures, and can provide valuable insight into human-machine and human-environment interfaces. Several sources contain valuable information about living and working in space, but are in an uncoordinated paper format. A relational database, called the Operational Experience Database, has been constructed to electronically store and organize human factors information from the Skylab and Space Shuttle missions. The taxonomy used to organize this database builds on the one used for the Skylab human-machine experiments. This information can be used by NASA engineers and operations personnel to remedy design problems, or expand on design successes.