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This method of gaging alignment of nut slots allows equal variations for location of the cotter pin hole in the bolt and location of slots in the nut. To inspect the nut, the slotted gage is inserted through the nut hole from the bearing surface of the nut. Alignment of slots is considered satisfactory if the gage pin can be slipped into the gage and nut slots without interference.

Round head bolts are made in two body styles: (a) A full size body, with a maximum diameter somewhat greater than the nominal diameter (not an SAE Standard except for ribbed neck bolts, Table 3); and (b) an undersize body, with a minimum diameter approximating the pitch diameter of the thread and a maximum diameter never exceeding nominal (SAE standard for all types except ribbed neck bolts). The body diameter of either style may be exceeded by a reasonable swelling or fin under the head, or under corners of the square necks, to the extent that serviceability is not affected.

Optical fiber has begun replacing copper in avionic networks. So far, however, it has been mainly restricted to non-critical applications (video transmission to the flight deck, IFE?). In order to take advantage of the high-bandwidth, low weight, no EMI properties of optical fibers in all data transmission networks, it will be necessary to improve the testing. One part of the puzzle, which is still missing, is the self-test button: the possibility to check the network and detect potential failures before they occur. The typical testing tool of a technician involved in optical fiber cables is the ?light source ? optical power meter? pair. With this tool, one can measure the insertion loss of the fiber link. A second important parameter, the return loss at each optical connector, is not analysed. In addition, this is only a global measurement, which does not allow the detection of possible weak points.

The System Architecture Virtual Integration (SAVI) program is a collaboration of industry, government, and academic organizations within the Aerospace Vehicle System Institute (AVSI) with the goal of structuring a new integration process that relies on a single-truth architectural framework. The SAVI approach of Integrate, then Build provides a modern distributed development environment which arrests the propagation of requirements errors through the development life cycle. It does so by capturing design assumptions and shared properties of the system design in an authoritative, annotated architectural model. This reference model provides a common, analyzable framework for confirming that system requirements remain complete, consistent, and correct at all levels of system decomposition. Core concepts of SAVI include extensive use of model-based system engineering tools and use of a single-truth reference architectural model.

In recent years, all major microprocessor manufacturers are transitioning towards the deploymenet of multiple processing cores on every chip. These multi-core architectures represent the industry consensus regarding the most effective utilization of available silicon resources to satisfy growing demands for processing and memory capacities. Porting off-the-shelf software capabilities to multi-core architectures often requires significant changes to data structures and algorithms. When developing new software capabilities specifically for deployment on SMP architectures, software engineers are required to address specific multi-core programming issues, and in the ideal, must do so in ways that are generic to many different multi-core target platforms. This talk provides an overview of the special considerations that must be addressed by software engineers targeting multi-core platforms and describes how the Java language facilitates solutions to these special challenges.

Translating service information into multiple human natural languages is a major expense for multinational corporations. Indeed corporations spend significant amounts to reduce their translation expense by managing the reuse text and its translation. The new frontier in reducing translation expense is translation avoidance, eliminating text through using illustrations and animations to communicate. Presenter Arnold Taube

The Java language is now the most popular programming language for the creation of new software capabilities. Its popularity has resulted in signficant economies of scale, with Java adopted as the primary language of instructional within many university curriculums, an abundance of reusable Java software components and Java software development tools available both from commercial suppliers and as open source technology, a large pool of competent Java developers from which to recruit staff, and a general willingness by senior staff software engineers to invest the effort required to learn this new programming language and technology. This talk describes the special approaches recommended for the use of Java in safety-critical deployments. The talk surveys the current state of the draft JSR-302 Safety Critical Java Specification and describes related experiences with commercially available technologies based on the constraints of early JSR-302 design discussions.

All Semi Vendors do have multi core CPUs in their portfolio and adding new devices every day. This is the only possibility to grow performance and fulfill Moore's law. Multi core offers a wide variety of possibilities to reduce hardware complexity, reduce power consumption, shrink board space, expand functionality and performance. On the other hand the software complexity goes up and this directly affects the ability to achieve a certified system. The main trend as of today and in the future is the rising number of cores in a single chip and the increasing functionality of the software. As this trend does not stop at safety critical systems, the System/Solution Architects have to question themselves how to guarantee data integrity, robustness, robust portioning, avoid multi point of failures and race conditions. This presentation will highlight ideas, do's and don'ts for those who will design a safety critical multi Core system today or in the near future.

Probabilistic methods are used in calculating composite part design factors for, and are intended to conservatively compensate for worst case impact to composite parts used on space and aerospace vehicles. The current method to investigate impact damage of composite parts is visual based upon observation of an indentation. A more reliable and accurate determinant of impact damage is to measure impact energy. RF impact sensors can be used to gather data to establish an impact damage benchmark for deterministic design criteria that will reduce material applied to composite parts to compensate for uncertainties resulting from observed impact damage. Once the benchmark has been established, RF impact sensors will be applied to composite parts throughout their life-cycle to alert and identify the location of impact damage that exceeds the maximum established benchmark for impact.

With the increase of functions in the next generation of aircrafts, it has become very important to address reconfigurability. The bottom line is that space and weight available for critical computers in an aircraft remain mostly unchanged. These new functions imply more computation power and so more redundant elements for safety. CPU power has been increased but the latest evolution with the new multi-core CPU's introduces additional difficulties in terms of certification. IMA first generation was the first answer to address some of these problems by enabling the concentration of several certified critical functions in the same physical computer. However, up to now, such implementations were very static and did not scale very well with the increase of functions need for the next generation aircraft. That?s why the avionics industry is looking for improvement of existing solutions and must work on what would be the next generation of IMA (IMA-NG).

With the growing use of carbon fiber composite structure in Aircraft Manufacturing, the challenge of drilling carbon fiber stacked with Titanium has become a focus point. Due to the abrasive nature of the carbon fiber (CF), cutting tool life is relatively short when drilling carbon fiber stalked with Titanium. A common drill wear indicator is exit burr formation in the Titanium. As drilling tools wear due to the abrasive nature of the CF, the exit burr in the in the Titanium increases. This study seeks to understand the factors that lead to tool wear and exit burr formation. A correlation may be made relating drilling thrust forces with exit burr formation. Different cutting tools geometries and materials are studied using a high speed camera to attempt to understand the factors influencing exit burr formation. Findings are optimized and tested. Decreasing exit burr in the drilling of CF and Titanium may increase tool life thereby reducing tool costs to airframe manufacturers.

The Pennsylvania State University is one of 16 North American universities that participated in the EcoCAR advanced vehicle technology competition (http://www.ecocarchallenge.org/). A series-hybrid-electric vehicle based on a General Motors crossover SUV platform has been designed, built and tested for this purpose. The powertrain features a 1.3 L turbodiesel engine running on a B20 fuel system, a 75kW generator directly coupled to the engine and advanced lithium-ion batteries. In this paper, the vehicle architecture and control strategy are detailed and performance predictions (e.g., acceleration, fuel consumption and emissions) are presented. This includes discussion of the development process that led to the selected designs. The predicted performance is compared with data obtained on a chassis dynamometer and during on-road measurements over specified drive cycles. Presenter Shawn Getty

Since 2006 Oak Ridge National Labs (ORNL) and the Pacific Northwest National Labs (PNNL) have conducted research of injection molded long glass fiber thermoplastic parts funded by U.S. DOE. At DOE's request, ACC's Plastics Division Automotive Team and USCAR formed a steering committee for the National Labs, whose purpose was to provide industry perspective, parts materials and guidance in processing. This ACC affiliation enabled the plastics industry to identify additional key research requirements necessary to the success of long glass fiber injection molded materials and their use in the real world. Through further cooperative agreements with Autodesk Moldflow and University of Illinois, a new process model to predict both fiber orientation distribution and fiber length distribution is now available. Mechanical property predictive tools were developed and Moldflow is integrating these models into their software.

The need for light-weighting of automotive structures has spurred on a tremendous amount of interest in and development of low cost carbon fiber composite materials and manufacturing. This presentation provides a description of the commercial carbon fiber concept compared to traditional aerospace and specialty carbon fiber products. A specific update is presented on the development and commercialization of new low cost carbon fiber based on lignin / PAN precursor technology. The second focus of the presentation is on carbon fiber composite manufacturing processes, including carbon SMC, RTM, prepregs, and thermoplastic processes. Advantages and disadvantages of these processes are discussed, especially related to low cost manufacturing. Presenter George Husman, Zoltek Companies Inc.

Biofuel usage is increasingly expanding thanks to its significant contribution to a well-to-wheel (WTW) reduction of greenhouse gas (GHG) emissions. In addition, stringent emission standards make mandatory the use of Diesel Particulate Filter (DPF) for the particulate emissions control. The different physical properties and chemical composition of biofuels impact the overall engine behaviour. In particular, the PM emissions and the related DPF regeneration strategy are clearly affected by biofuel usage due mainly to its higher oxygen content and lower low heating value (LHV). More specifically, the PM emissions and the related DPF regeneration strategy are clearly affected by biofuel usage due mainly to its higher oxygen content and lower low heating value, respectively. The particle emissions, in fact, are lower mainly because of the higher oxygen content. Subsequently less frequent regenerations are required.

The ISO 26262, titled "Road vehicles - Functional safety," is a Functional Safety standard that gives a guidance to reduce the risks to tolerable level by providing feasible requirements and processes. This standard is an adaptation of the Functional Safety standard IEC 61508 for Automotive Electrical/Electronic and programmable electronic Systems. The standard covers the development of safety-related electrical, electronic and programmable electronics systems in the road vehicles. It will have a significant impact on the way such systems are designed, developed, integrated and validated for safety. Functional safety of embedded systems has become an integral part in automotive engineering activities due to the recently released safety standard ISO 26262. One main challenge is to perform development activities compliant to the standard and provide the respective documentation.

In this project funded by the Bayerische Forschungsstiftung two fundamental investigations had been carried out: first a new N-rich liquid ammonia precursor solution based on guanidine salts had been completely characterized and secondly a new type of side-flow reactor for the controlled catalytic decomposition of aqueous NH3 precursor to ammonia gas has been designed, applied and tested in a 3 liter passenger car diesel engine. Guanidine salts came into the focus due to the fact of a high nitrogen-content derivate of urea (figure 1). Specially guanidinium formate has shown extraordinary solubility in water (more than 6 kg per 1 liter water at room temperature) and therefore a possible high ammonia potential per liter solution compared to the classical 32.5% aqueous urea solution (AUS32) standardized in ISO 22241 and known as DEF (diesel emission fluid), ARLA32 or AdBlue®. Additionally a guanidine based formulation could be realized with high freezing stability down to almost ?30 °C (?