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Simulation of avionics equipment is essential due to the complex nature of its development and integration process. Throughout the development process, executable component models are used to demonstrate the feasibility and the compliance of the system design with respect to its functional requirements. In later development phases, there is the need for system integration tests where a mix of real and simulated equipment is used to verify the overall system behavior. Since Boeing 777 and Airbus A380 programs, IMA1 technology has entered several civil aircraft systems. In recent programs like Boeing 787 and Airbus A350 the number of IMA components has significantly increased. In this paper we present a simulation model for a new IMA component - the common Remote Data Concentrator (CRDC)2, which is developed by Thales-Diehl for the Airbus A350 XWB. Building simulation models of IMA components is in general a challenging task due to their complexity on both software and hardware level.

The objective of the work discussed within this paper is to present a modeling methodology to assess thermal management system (TMS) concepts for aircraft to determine adequacy in meeting thermal requirements and constraints for the duration of the flight1. To accomplish this, an analysis tool that has the capability to investigate steady state and transient thermal hydraulic conditions on a component to system-wide level is employed. This is achieved by simulating the conditions within a cooling network to provide temperature, pressure and mass flow rate distributions, as well as the temperature of surrounding engine and airframe structures. With today's reduced budgets, new aircraft systems will be less common and retrofitting existing high performance aircraft will become more common. Pushing these technologies to their thermal limits is resulting in cooling requirements that were not present or even contemplated during their original designs.

Overloading of trucks can easily cause damage to roads, bridges and other transportation facilities, and accelerate the fatigue loss of the vehicles themselves, and accidents are prone to occur under overload conditions. In recent years, various countries have formulated a series of management methods and governance measures for truck overloading. However, the detection method for overload behavior is not efficient and accurate enough. At present, the method of dynamic load identification is not perfect. No matter whether it is the dynamic weight measurement method of reconstructing the road surface or the non-contact dynamic weight measurement method, little attention is paid to the difference of different vehicles. Especially for different vehicles, there should be different load limits, and the current devices are not smart enough.

Searching the Location-Based Service (LBS) on the Internet, such as Yellow Pages, has the advantage to have the most updated information, for free (at least for the moment). Due to a number of limitations, mobile users still encounter many troubles when they use wireless device to perform online LBS searching. Providing a convenient access to the online LBS information for those wireless users is a challenging problem and also a business opportunity. In this paper, we focus on building intelligent agents to provide online LBS via wireless Internet accessing. Such an agent, based on address identification, can analyze the content of certain Web pages (ex. Yellow Pages) to search desired LBS information. We propose an ontology-based conceptual information retrieval approach combined with tree structure matching and the nearest neighbor methods to perform this task.

LBS (location-based service) is an important component of navigation assistance systems. Modern onboard devices employ CD-based or DVD-based data storage. In this paper, we are interested in techniques that can be used to build agents for searching and accessing online LBS information. Such agents must be capable of content-based analysis, as most LBS information provided by text in a Web page cannot be easily classified and identified by a keyword search engine. We propose an ontology-based conceptual information retrieval method to perform real-time online LBS information access. The proposed method allows the automatic identification of addresses as structural knowledge through graph matching. Location-based information can then be retrieved and extracted on the basis of addresses: the abundant location-based services provided by YellowPages are an example.

This study was undertaken to identify methods of unique identification of commercial vehicles at the roadside for slow and high-speed electronic screening purposes. It is a comprehensive look at available and emerging technologies, focusing on the needs of the Federal Highway Administration’s Office of Motor Carrier and Highway Safety (OMCHS) and the States. The study included both a needs assessment and a technology evaluation. A preliminary list of 22 technologies was developed that appeared to have some applicability to the task of roadside identification of commercial vehicles. As the technology evaluation progressed, five of these technologies (optical character recognition, radio frequency identification, barcode, image capture, and voice recognition) emerged as demonstrating the greatest potential for roadside identification of commercial vehicles. These five technologies were evaluated in some detail, and recommendations were developed.

Both the electrical portion of the powertrain and the rising number of auxiliary systems will considerably increase the electrical power requirements in future vehicles. In addition, multiple voltage supply levels will enhance the complexity of the electrical distribution system (EDS), while strict cost, weight, packaging, and safety constraints must be upheld, posing serious design challenges in terms of robustness, reliability and energy efficiency. Currently, a self-contained integral test or evaluation of the EDS is normally not applied. For such a purpose, quantitative quality criteria are introduced here which allow a comparative assessment of an EDS by addressing the dynamic and static stability of the supply voltage, the reliability of the fusing system, and the ability to provide the required electrical power. The presented approach uses both precisely-defined test scenarios and a comprehensive EDS test bench.

As manufacturers of air-cooled diesel engines, the company of Klöckner-Humboldt-Deutz (KHD) undertook the rather rapid development of a multifuel engine on the basis of a proved mass-produced, air-cooled unit. Being equal in output, this new engine had to run on all fuels and fuel mixtures obtainable at gasoline stations without any modifications being necessary. Preferably, it had to be produced by means of the same manufacturing facilities as the series engine and features a maximum number of identical parts. The solution to the problem involves supplementing the series engine with a high-tension ignition system employing a special spark plug in the direct vicinity of the injection nozzle. This spark plug can be subsequently installed following the rework of standard parts. By using the same basic setting of injection and ignition for all fuels, it is possible to attain absolutely knock-free combustion, with a gentle compression curve and a minimum of cyclic pressure variations.

This paper describes the use of a new probe for direct measurement of particle velocity for an acoustic intensity survey of a test engine at Ricardo UK. The new probe includes both a pressure and a particle velocity transducer in a single package [2], utilising the miniature hot wire principle. This probe enables near-field direct measurement of the acoustic intensity on a test powertrain, and is referred to here as the ‘P-U’ (Pressure- Velocity) Probe. The new technique has significant advantages over the traditional pressure differential acoustic intensity technique that include a wider frequency bandwidth, better rejection of the reverberant sound field and the ability to easily and safely take measurements over a wider range of engine operating conditions. The use of the method for noise source identification is described and the test results are shown to compare well with those obtained from the traditional pressure differential acoustic intensity technique.

As part of the development of a New SAE Recommended Practice for Brake Natural Frequency and Damping Measurements, the US Working Group on Brake NVH conducted a series of Round Robin tests and developed detailed recommendations for such measurements. The results of these tests are summarized in this paper. Initial results showed that there were difficulties with the identification of the types of modes being measured. However, when the results were carefully categorized, the measured natural frequencies agreed quite well. The measured damping coefficients showed much larger variations. In some instances, differences of more than 200% were found between testers. The steps taken to improve the consistency of results and subsequent Round Robin tests are described.

The vehicle overload seriously jeopardizes traffic safety and affects traffic efficiency. At present, the static weighing station and weigh-in-motion station are both relatively fixed, so the detection efficiency is not high and the traffic efficiency is affected; the on-board dynamic weighing equipment is difficult to be popularized because of the problem of being deliberately damaged or not accepted by the purchaser. This paper proposes an efficient, accurate, non-contact vehicle overload identification method which can keep the road unimpeded. The method can detect the vehicle overload by the relative distance (as the characteristic distance) between the dynamic vehicle's marking line and the road surface. First, the dynamics model of the vehicle suspension is set up. Then, the dynamic characteristic distance of the traffic vehicle is detected from the image acquired by the calibrated camera based on computer vision and image recognition technology.

This paper presents a free-form optimization method for achieving a desired stiffness in the shape design of automotive sheet metal structures. A squared error norm of displacements at loaded points is introduced as an objective functional in the formulation of a distributed-parameter shape identification problem. The shape gradient function theoretically derived for this problem is applied to the non-parametric free-form optimization method for shells that was developed by one of the authors. With this method, an optimal arbitrarily formed shell, or a shell with optimal curvature distribution can be obtained without any shape parameterization. The calculated results show the effectiveness and the practical utility of the proposed method for controlling stiffness when designing sheet metal structures.

Dynamic load analysis for qualifying aerospace structures often requires that the analytical based modal models have modes which have been verified or derived directly from a normal mode identification test. Normal modes are the characteristic solution of a lumped parameter eigenvalue problem, and including measured normal modes in loads analysis assures the correct contribution of each mode in forming the linear combinations of the modal response. The difficulty in testing for normal modes is that most structures are not truly linear and have physical limitations which prevent placing the exciters in the ideal locations needed to isolate and define normal modes. A normal mode test approach utilizing multiple exciter inputs was successfully used on a TRW spacecraft. Several testing and analysis techniques were utilized and compared. The approach demonstrates the need for multiple indicators to assure confidence in testing.

Battery models are often applied to describe the dynamic characteristics of batteries and can be used to predict the state of the battery. Due to the process of charging and discharging, the battery heat generation will cause the inhomogeneity between inner battery temperature and surface temperature. In this paper, a novel battery impedance model, which takes the impact of the battery internal temperature gradient on battery impedance into account, is proposed to improve the battery model performance. Several experiments are designed and conducted for pouch typed battery to investigate the electrochemical impedance spectroscopy (EIS) characteristics with the artificial temperature gradient (using a heating plate). Experimental results indicate that the battery internal temperature gradient will influence battery EIS regularly.

Current methods of machine calibration and software compensation focus on either the joint motion errors (classic machine tool software compensation) or the geometric errors between the joints (robot calibration). However, both types of errors have a significant impact on the volumetric accuracy of a machine tool or robot. We have developed a calibration method that simultaneously identifies joint motion errors and geometric errors in a machine or robot with an arbitrary number and arrangement of links using a laser tracker. The simultaneous identification of all error sources decreases measurement time, with a typical calibration for a moderate sized machine taking about four hours and 200-500 measurements. The model presented is based on a mathematically minimal parametric model of the machine. Parameter identification is done in a statistically significant way, resulting in both the “best-fit” values for the parameters and the statistical confidence in those values.

Forty billion dollars are lost each year due to the failure of various components in a vast array of electronic devices. These failures result in downtime for part replacement, product liability issues, and critical safety ramifications. Many of the failures are caused by corrosion due to the migration of moisture or solder flux through leak paths inherent in electronic connectors and other parts, typically at the interface between metal leads and plastic housings into which they are molded. All industry standard approaches to preventing these failures have severe limitations and drawbacks. The approaches include discarding parts that fail a leak test, employing elaborate hermetically sealed encasements, or applying surface sealants. Each method of solving the problem creates other problems: costly high scrap rates, heavy, bulky assemblies, or introduction of a foreign material through surface sealants.

Despite the fact that Transfer Path Analysis (TPA) is a well known and widely used NVH tool it still has some hindrances, the most significant being the huge measurement time to build the full data model. For this reason the industry is constantly seeking for faster methods. The core concepts of a novel TPA approach have already been published in a paper at the ISMA 2008 Conference in Leuven, Belgium. The key idea of the method is the use of parametric models for the estimation of loads. These parameters are frequency independent as opposed to e.g. the classical inverse force identification method where the loads have to be calculated separately for each frequency step. This makes the method scalable, enabling the engineer to use a simpler model based on a small amount of measurement data for quick troubleshooting or simply increase accuracy by a few additional measurements and using a more complex model.

15 years of NVH applications make Transfer Path Analysis (TPA) appear a commodity tool. But despite the fact that TPA is today successfully used in a large variety of applications in automotive and mechanical industries, its main bottleneck remains the huge measurement time to build the full TPA model. This paper presents a new TPA method that provides a good compromise between path accuracy and measurement time. The method is also referred to as OPAX. The key idea of OPAX is the use of simplified parametric load models with limited number of model parameters. The main advantage of this is that one should measure only a small amount of FRF data to identify the operational loads. This drastically reduces measurement time and efforts. In addition to this, the OPAX method does not require mount stiffness data and allows a simultaneous identification of structural and acoustic paths.

It is apparent that a new generator and regulator design is needed to supply the additional electrical loads and meet the requirements for durability, reliability, and environmental protection on earthmoving equipment. The author discusses the d-c and alternator type systems which have been used to supply electrical needs. A detailed analysis of the integral charging system is presented. This system overcomes many of the shortcomings of the present electrical systems and, because it has a minimum number of moving parts, it is potentially the most reliable charging system in use on heavy duty equipment.

The relatively rare occurrence of injury or fatality in fuel-fed fires has received considerable attention in automotive safety rulemaking and products liability litigation. The literature related to fatalities associated with fire is confirmed by recent FARS data, and there are no reliable field data which confirm a need for further injury-reducing effect related to FMVSS 301. NHTSA has acknowledged this by removing crash fire rulemaking from its priorities plan. The police-reported crash fire data now available must be supplemented with in-depth investigation by trained teams before informed judgements can be made regarding further safety improvements with respect to crash fire injury.