A Novel Drive Cycle Simulation Model for Gasoline Engines to Investigate Bandwidth Coverage of Emission Performance and Fuel Consumption with Engine Control Parameters

The presented work is offering an investigation how the bandwidth of vehicle specific attributes is impacting engine control parameter requirements for warmup control of the catalytic converter, aiming to ease the development process by providing mathematical means for an automatic generation of control settings. For the specific purpose, a novel drive cycle simulation approach is developed, focusing on emission performance and fuel consumption of a gasoline engine. Steady state and quasi steady state measurements are collected to quantify the impact of modifications to control parameters on emission concentration, exhaust gas temperature and engine torque, especially directly after a cold start. A run-time efficient simulation model, based on polynomial equations is set up to generically describe the identified physical and chemical effects. Control system dynamics, warmup effects, control parameter modifications and the interactions of control settings with each other and with engine temperature are considered. A catalytic converter model which is developed in an accompanying work is incorporated to establish comparability of results to vehicle measurements. The model has been extensively correlated to measurement data. Measurement and model are agreeing very well with differences being discussed in detail. To visualize bandwidth dependencies, the model is used to quantify the relationship of vehicle attributes, control modifications and engine performance measures by a linear modulation of the corresponding parameters. Multiple physical and chemical effects are identified that impact the overall emission result independently from each other. While the sensitivity to changing control parameters and vehicle specific attributes is found to vary significantly in magnitude, trends are comparable on the NEDC and WLTC profile. II Transferring the obtained results into mathematical relationships, an offline optimization of engine control parameters based on vehicle specific attributes is attempted which is additionally taking practical feasibility into account. It is demonstrated that a single set of control parameters is fulfilling emission requirements of an entire pre-defined product portfolio without significantly sacrificing fuel economy or robustness. The novel methodology is proposed to be implemented into a standard development process, both for handling product complexity as well as to optimize product cost by actively incorporating controls optimization into hardware design and system layout during an early stage of the development process. Given the consistency and transparency of results, the established methodology is offering significant potential for further academic studies

Hypothesis For Prediction Of Stimulant Drug Effectiveness Utilizing Sensory Integrative Diagnostic Methods

Despite extensive research, there has been no way to predict before drug administration which children with attention deficit hyperactivity disorder (ADHD) will respond to medication intended to calm them. A drug trial is the current method used. This paper discusses the action of stimulant medications and presents a hypothesis as to why they work on some children and not others. Sensory integration theory, particularly on vestibular system measures, that involves differential diagnosis of certain types of ADHD children, is used to explain why some children respond to stimulant medications

Prediction of Methylphenidate (Ritalin) Responsiveness Through Sensory Integrative Testing

Seventeen children previously judged to be good or poor responders to methylphenidate (Ritalin) were tested on sensory integrative measures while in the off-drug state. The tester was unaware of the children\u27s drug response category. Results showed that children who were poor responders to Ritalin showed prolonged scores on and an adverse reaction to the Southern California Postrotary Nystagmus Test and had poorer equilibrium reactions and lower double tactile stimuli scores than the children judged good responders to Ritalin. These findings suggest that it might be possible to identify good and poor responders to Ritalin before the medication is given, something not previously thought possible. The current method for making this distinction is through a drug trial. These findings also indicate that there are at least two discernible types of hyperactivity associated with attention deficit disorders (ADD) that are theoretically related to differences in vestibular processing: one related to underaroused or overinhibited lower brain centers, and another related to deficient inhibition from higher brain centers. The good responders to Ritalin appear to be the underaroused group, the same population that responds to sensory integrative occupational therapy techniques. This implies that perhaps occupational therapy could be used to reduce the medication needs of these children

Detecting and Outlining Potential Wildfire Areas via Satellite Imagery

Services that track wildfire spread and trajectory can provide such information and issue related alerts. The information obtained from current services is often stale and ineffective in helping people determine whether they are likely to be harmed by the fire. Moreover, such information is not in a form that lay persons can easily grasp, thus making it difficult for them to derive actionable insight from the received information. This disclosure describes techniques to leverage satellite imagery to automatically detect and outline the boundaries of large fires. The outlined boundaries are updated regularly and surfaced as appropriate within various pertinent applications and platforms such as in digital maps, virtual assistant interfaces, search results, social media, etc

Improved Hc2 in Bulk-Form Magnesium Diboride by Mechanical Alloying With Carbon

High energy milling of MgB2 pre-reacted powder renders the material largely amorphous through extreme mechanical deformation and is suitable for mechanically alloying MgB2 with dopants including carbon. Bulk samples of milled C and MgB2 powders subjected to hot isostatic pressing and Mg vapor annealing have achieved critical fields in excess of 32T and critical current density approaching 10^6 A/cm^2.Comment: 13 pages, 3 figures references updated, typos corrected, numerical error correcte

Modification of intergrain connectivity, upper critical field anisotropy, and critical current density in ion irradiated MgB2 films

We study the effect of 100 MeV Silicon and 200 MeV Gold ion irradiation on the inter and intra grain properties of superconducting thin films of Magnesium Diboride. Substantial decrease in inter-grain connectivity is observed, depending on irradiation dose and type of ions used. We establish that modification of sigma band scattering mechanism, and consequently the upper critical field and anisotropy, depends on the size and directional properties of the extrinsic defects. Post heavy ion irradiation, the upper critical field shows enhancement at a defect density that is five orders of magnitude less compared to neutron irradiation. The critical current density however is best improved through light ion irradiation.Comment: 18 pages, 4 figures, submitte

Very high upper critical fields in MgB2 produced by selective tuning of impurity scattering

We report a significant enhancement of the upper critical field $H_{c2}$ of different $MgB_2$ samples alloyed with nonmagnetic impurities. By studying films and bulk polycrystals with different resistivities $\rho$, we show a clear trend of $H_{c2}$ increase as $\rho$ increases. One particular high resistivity film had zero-temperature $H_{c2}(0)$ well above the $H_{c2}$ values of competing non-cuprate superconductors such as $Nb_3Sn$ and Nb-Ti. Our high-field transport measurements give record values $H_{c2}^\perp (0) \approx 34T$ and $H_{c2}\|(0) \approx 49 T$ for high resistivity films and $H_{c2}(0)\approx 29 T$ for untextured bulk polycrystals. The highest $H_{c2}$ film also exhibits a significant upward curvature of $H_{c2}(T)$, and temperature dependence of the anisotropy parameter $\gamma(T) = H_{c2}\|/ H_{c2}^\perp$ opposite to that of single crystals: $\gamma(T)$ decreases as the temperature decreases, from $\gamma(T_c) \approx 2$ to $\gamma(0) \approx 1.5$. This remarkable $H_{c2}$ enhancement and its anomalous temperature dependence are a consequence of the two-gap superconductivity in $MgB_2$, which offers special opportunities for further $H_{c2}$ increase by tuning of the impurity scattering by selective alloying on Mg and B sites. Our experimental results can be explained by a theory of two-gap superconductivity in the dirty limit. The very high values of $H_{c2}(T)$ observed suggest that $MgB_2$ can be made into a versatile, competitive high-field superconductor.Comment: An updated version of the paper (12/12/2002)that was placed on cond-mat on May 7 200

Synthesis and Properties of c-axis Oriented Epitaxial MgB2 Thin Films

We report the growth and properties of epitaxial MgB2 thin films on (0001) Al2O3 substrates. The MgB2 thin films were prepared by depositing boron films via RF magnetron sputtering, followed by a post-deposition anneal at 850C in magnesium vapor. X-ray diffraction and cross-sectional TEM reveal that the epitaxial MgB2 films are oriented with their c-axis normal to the (0001) Al2O3 substrate and a 30 degree rotation in the ab-plane with respect to the substrate. The critical temperature was found to be 35 K and the anisotropy ratio, Hc2(parallel to the film) / Hc2(pendicular to the film), about 3 at 25K. The critical current densities at 4.2 K and 20 K (at 1 T perpendicular magnetic field) are 5x10E6 A/cm2 and 1x10E6 A/cm2, respectively. The controlled growth of epitaxial MgB2 thin films opens a new avenue in both understanding superconductivity in MgB2 and technological applications.Comment: 10 pages, 6 figure