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Early-stage hot-electron generation has injected electrons into the shallow trench isolation (STI) edge above the drift region that has caused the linear-region drain current to increase in the first moment of the stress of P-LDMOS transistors. The studies have shown that the amount of current increase has depended on the distance from the maximum impact ionization generation rate point to the STI.

Despite the unprecedented popularity of separation chromatography, the measurement of coeluting isomeric chemicals remains an extremely difficult task. We developed an analytical scheme capable of measuring two coeluting isomers using a single chromatographic column and a gas chromatography/tandem mass spectrometry system. The protocol utilized two product ion fragments generated from a common parent ion associated with the isomers for quantitation. The utility of the analytical scheme was demonstrated with the measurements of several pairs of coeluting polychlorinated biphenyl (PCB) isomers in standard solutions and fish liver samples. Best results were given when a set of stringent constraints for the abundance ratio of the two product ion fragments was satisfied. Analyses of seven fish liver samples collected from nearshore San Diego, CA, indicated that the domain that had been previously reported to comprise PCB 153 and PCB 168 actually contained PCB 153 only. Although only a selected number of PCB congeners were examined, the results presented indicate that the analytical scheme has the potential to be used to determine the concentrations of all chromatographically coeluted isomers.

A method for solving inclusions of the form 0 (subset) F(x) is discussed. By using a concept of derivative for multifunctions, a multifunction's derivative is defined by means of a proper tangent cone to its graph. A new concept of tangent cone is provided. After describing a solution to the inclusion through an iterating method, an open mapping theorem for multifunctions different from the results are presented.

Electromechanical coupling coefficients of piezoelectric elements are determined using the Berlincourt et al. formula for a uniform electrostatic state and Mason's formula for near resonance frequencies. Analysis of the methods is given along with mention of a third formula. The third formula is applicable for both static and dynamic electrostatic state. The results of the third formula are seen to be in good agreement with the formulas of Berlincourt and Mason.

This paper presents a graph theory-based approach to optimum type synthesis of vehicle suspension mechanisms using an expert system. Kinematic chain isomorphism is identified, using an extended degree method to facilitate the enumeration of kinematic structures. Rules representing design criteria and the flow value theory based on energy loss calculation are incorporated in the rule base to evaluate and select mechanisms among those that are enumerated in the database. Statistical variance calculation serves to complement the flow value theory. A new method called the extended flow value method is devised for isomorphism checking of labeled graphs. In the spirit of increasing emphasis on the riding quality of vehicles, several novel suspension configurations are created to ensure maintenance ease and vibration damping efficiency.

Byline: K. Aekbote, L. Zhao, M. Maltarich, J. Cheng, C.C. Chou, K.H. Yang This paper describes the development of a new door subsystem sled test methodology to simulate the occupant responses in NHTSA's 75° oblique pole side impact test mode using SID-IIs and ES-2re dummies. This sled subsystem test methodology consists of a door sled oriented at 75°, with the dummy on a seat located at the same distance from the door as in full-vehicle test, to simulate gap closure for evaluating side airbags. The door sled is accelerated to an initial velocity of 20 mph and then impacts the stationary pole. From the onset of door contact with the pole, the velocity of door sled is decelerated following the non-struck side velocity of the vehicle by means of VIA decelerator. The validation of the test methodology with both SID-IIs and ES-2re dummies is presented by comparing their respective responses between the sled subsystem and full-vehicle tests.

Byline: K. Aekbote, J. Cheng, C. Wang, C.C. Chou, K.H. Yang This paper describes in detail the comparison of structural responses and their effect on occupant responses between the moving deformable barrier and oblique pole test modes, including the test protocol, dummies and injury metrics. The temporal sequence of events that takes place in each of these test modes are presented in light of the primary momentum exchanges and the underlying physics. Furthermore, the key factors that affect dummy responses in each of these test modes are identified and summarised. Additionally, a brief conceptual framework to understand overall vehicle and occupant dynamics is presented. Vehicle crash dynamics covers the analyses of vehicle effective mass, vehicle lateral stiffness and structural analysis using momentum and energy conservation, for design and development of vehicle structure and simulation of structural responses using sub-system test/CAE methodology. Occupant dynamics focuses on analysis of dummy's body regions including head, neck, thorax, pelvis and upper leg to develop countermeasures and better understand the effectiveness of side restraints such as airbags.

Byline: A. Deb, C.C. Chou Computer-aided engineering (CAE), based on techniques like finite element modeling and analysis, can be considered as the backbone for designing complex systems such as automobiles. However, for highly nonlinear problems such as automotive crashworthiness and occupant safety design, a major problem is posed in terms of computational efficiency, modelling efforts, and model quality. For a design engineer, thus, judicious employment of various tools such as statistical regression analysis, lumped parameter modeling, and detailed finite element-based simulation can be the key for achieving an optimised design in a competitive design cycle. The current study highlights a hybrid methodology resulting from the application of these various techniques in an integrated manner for front impact safety design of vehicle platforms. In particular, new regression models are presented and the hybrid approach is demonstrated with an aluminium-intensive vehicle using LS-DYNA for detailed frontal US-NCAP analysis.

The Isotopic Composition of Methane in Polar Ice Cores ATMOSPHERIC METHANE IS A greenhouse gas second only to CO.sub.2 in its effect on global temperatures: the atmospheric warming associated with [...]

The electromechanical properties of an asymmetric piezoelectric/elastic laminated actuator were investigated using electroelasticity analysis. The axial expansion-bending coupled motion of the device was divided into quasi-axial expansion and quasi-bending by its physical significance of vibration modes. Results show good agreement between theoretical and experimental data, indicating the validity of the laminated specimen.