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Vehicle Accident Analysis and Reconstruction Methods, Second Edition

Thoroughly revised, this new edition builds on the original exploration of accident analysis, reconstruction, and vehicle design. Enhanced with new material and improved chapters on key topics, an expanded glossary of automotive terms, and a bibliography at the end of the book providing further reading suggestions make this an essential resource reference for engineers involved in litigation, forensic investigation, automotive safety, and crash reconstruction. ...Designed for the experienced practitioner, this new book aims to help reconstruction specialists with problems they may encounter in everyday analysis. The authors demonstrate how to take the physics behind accidents out of the idealized world and into practical situations. ...The authors demonstrate how to take the physics behind accidents out of the idealized world and into practical situations. Real-world examples are used to illustrate the methods, clarify important concepts, and provide practical applications to those working in the field.
Technical Paper

Sensitivity of Accident Reconstruction Calculations

A number of simplistic formulae, based on particle dynamics, energy, and momentum methods are routinely employed by accident reconstructionists to calculate vehicle speeds immediately prior to impact. It is almost always the case that scene evidence and other information regarding important variables involved in such equations must either be estimated or can be measured only in an approximate way. ...Example problems illustrate the difficulties faced by accident reconstructionists as they grapple with incomplete and/or estimated values for important variables, and with the inherent sensitivity of some of the calculations to seemingly small variations in variable magnitudes.
Journal Article

Automatic Transmission Gear Ratio Optimization and Monte Carlo Simulation of Fuel Consumption with Parasitic Loss Uncertainty

An enterprise approach for vehicle fleet balancing of fuel consumption objectives based upon selection of automatic transmission gearing strategy is presented. Monte Carlo simulations for the influence of parasitic loss uncertainty for the automatic transmissions selected from the generalized DOE were conducted to determine the range of fuel consumption that might be realized in production. ...Automatic transmission gearing parameter selection was unaffected by the variation introduced by the Monte Carlo simulations, but did show fuel consumption performance to vary upwards of 9 g CO2/km depending on applications and to have a direct impact on powertrain operating parameters.
Technical Paper

Particulate Matter Formation Dynamics as Investigated by Ultra-Accelerated Quantum Chemical Molecular Dynamics Coupled with Canonical Monte Carlo Method

Suppression or reduction of soot emissions is an important goal in the development of automotive engines for environmental and human health purposes. A better understanding at the molecular level of the formation process of soot particles resulting from collision and aggregation of smaller particles made of Polycyclic Aromatic Hydrocarbon (PAH) is needed. In addition to experiments, computational methods are efficient and valuable tools for this purpose. As a first step in our detailed computational chemistry study, we applied Ultra-Accelerated Molecular Dynamics (UAQCMD) and Canonical Monte-Carlo (CMC) methods to investigate the nucleation process. The UA-QCMD can calculate chemical reaction dynamics 107 times faster than conventional first principle molecular dynamics methods, while CMC can calculate equilibrium properties at various temperatures, pressures, and chemical compositions.
Technical Paper

On the Development of a Comprehensive Hazard Modeling Tool through Distributed Simulation: Learning from the Columbia Space Shuttle Accident

Although there was no human casualty reported, the outcome of this accident could have been much different. In this paper, we investigate the use of distributed simulation and information fusion to better predict the effects, in terms of expectations of casualties (EC), of the different hazards produced by an accidental or instructed loss of such a vehicle.
Technical Paper

Application of Signal Reconstruction to On-Road Emissions Testing

Data was taken from these analyzers and passed, off-line, through the reconstruction filter. In addition, part of the Federal Urban Driving Schedule was simulated on the chassis dynamometer and emissions data collected from the test vehicle.
Technical Paper

Signal Reconstruction Applied to a Fast Response Flame Ionisation Detector

The Fast-response Flame Ionisation Detector is used to measure levels of un-burnt hydrocarbons in the cylinder and exhaust of engines. Its fast response allows uHC emission processes to be resolved within an engine cycle. This paper describes a method for obtaining even greater detail by post-processing the output of the device using a Finite-Impulse Response (FIR) digital filter. The specification of the filter can be obtained by understanding the flow regimes within the sampling system. Examples from in-cylinder and exhaust sampling are presented with suggestions for implementation and further improvement.
Technical Paper

Performance of a Non-Lacerative Windshield in Case of Accident and Under Environmental Conditions

The four-layer laminated Securiflex windshield has been tested in simulated collisions at the Wayne State University up to 40 mph Barrier Equivalent Velocities, to demonstrate that it causes no laceration. has been exposed to usual and extreme environmental conditions to demonstrate its serviceability in field use. The new windshield consists of a conventional laminated construction (glass/high penetration resistant interlayer/glass) combined with a 0.5 mm innerlayer of plastic. Glass is used on the outer surface of the windshield to withstand the abrasion and scratching of sand, windshield wipers and cleaning. The laminated construction prevents penetration and provides a pocket or cushion action to decelerate the head without injury. The innerlayer is made of a special plastic film which protects the face of the occupants against laceration and eye injury during head impact.
Technical Paper

Reconstruction of the Cylinder Pressure from Vibration Measurements for Prediction of Exhaust and Noise Emissions in Ethanol Engines

There are growing demands for condition monitoring of IC engines, and therefore any method in order to improve the performance of the engines ought to be evaluated. This paper proposes a new approach for the prediction and optimisation of noise and exhaust emissions in IC engines. The idea is to reconstruct the cylinder pressure from vibration measurements on the engine surface by using the complex cepstrum method [3, 4]. The reconstructed cylinder pressure is further used as input in Multivariate models, based on cylinder pressure, for estimating noise and exhaust emissions. This paper demonstrates the applicability of the method for modelling of noise and exhaust emissions
Journal Article

Neutron Transport Models and Methods for HZETRN and Coupling to Low Energy Light Ion Transport

Both models are compared to the Monte Carlo codes HETC-HEDS and FLUKA, and the DC model is shown to agree closely with the Monte Carlo results. ...Both models are compared to the Monte Carlo codes HETC-HEDS and FLUKA, and the DC model is shown to agree closely with the Monte Carlo results. Finally, it is found in the development of either model that the decoupling of low energy neutrons from the light ion (A≤4) transport procedure adversely affects low energy light ion fluence spectra and exposure quantities.
Technical Paper

Stochastic Approach to Spacecraft Thermal Control Subsystem

To perform this type of analysis the stochastic theory and the Monte Carlo method are used. This will be applied to the critical periods like worst case determination, sensitivity analysis, design limits or test correlation.
Technical Paper

Parametric Investigation of Ice Shedding from a Business Jet Aircraft

This methodology combines experimental aerodynamic characteristics of ice fragments, computational fluid dynamics, trajectory analysis and the Monte Carlo method to provide probability maps of shed particle footprints at desired locations. ...Trajectories of a rectangular plate shed from the wing and windshield of a generic business jet are presented in this paper. Monte Carlo simulations for two aircraft speeds, three angles of attack and one yaw angle are also included to demonstrate the effect of shed location and initial particle orientation on plate trajectory path. ...In most of the Monte Carlo simulations, however, it was found that a considerable amount of fragments may collide with the fuselage.
Technical Paper

Uncertainties in Measurements of Emissions in Chassis Dynamometer Tests

Data from one steady state propane injection test and a transient driving cycle are used to compare results from our analysis and Monte Carlo simulation. It is found that the Monte Carlo simulation shows good agreement with the results from the uncertainty analysis. ...A computer generated Monte Carlo simulation is used to validate the present analysis. Data from one steady state propane injection test and a transient driving cycle are used to compare results from our analysis and Monte Carlo simulation.
Technical Paper

Limitations of Real-Time Engine-Out NOx Estimation in Diesel Engines

In our paper we analyze the effect of input uncertainty on the accuracy of engine-out NOx estimates via a numerical Monte Carlo simulation and show that this effect can be significant. Even though our model is based on an in-cylinder pressure sensor, this sensor is limited in its capability to reduce the effect of other measured inputs on the model.