Sensor Simulation and position calibration for the CMS pixel detector

In this paper a detailed simulation of irradiated pixel sensors was used to investigate the effects of radiation damage on charge sharing and position determination. The simulation implements a model of radiation damage by including two defect levels with opposite charge states and trapping of charge carriers. We show that charge sharing functions extracted from the simulation can be parameterized as a function of the inter-pixel position and used to improve the position determination. For sensors irradiated to Phi=5.9x10^14 n/cm^2 a position resolution below 15 um can be achieved after calibration.Comment: Presented at the 14th Int. Workshop on Vertex Detectors (Vertex 2005), November 7-11 2005, Chuzenji Lake, Nikko, Japan. 4 pages, 1 figur

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Nitric oxide conversion in a spark-ignited natural gas engine

A large percentage of stationary engine applications are natural gas fueled. The cleanest of these large bore engines currently produce on the order of one gram of NOx per brake-horsepower hour (g/bhp-hr) of work done. The goal of this work is to reduce these emissions to 0.1 g/bhp-hr levels. Selective NOx Recirculation (SNR) is a technology which will help achieve these 0.1 g/bhp-hr levels. SNR has been proven in gasoline and diesel engines, with up to 90% NOx conversion rates being achieved, but not much is known about its overall efficiencies when used with natural gas engines. This technique involves adsorbing NOx from an exhaust stream, then selectively desorbing the NOx into a concentrated NOx stream, which is fed back into the engine, thereby converting a percentage of the concentrated NOx into harmless gases. Understanding the NO conversion process plays a major role in optimizing the SNR technology. The NO conversion process was modeled using CHEMKIN, a chemical kinetic solver. The results showed decreasing the air-fuel ratio of the engine to slightly rich operation and adding EGR could increase the experimentally measured NO conversion of approximately 20% up to 90%

Some Choctaw sentence structures

From the introduction: Being somewhat familiar with Longacre\u27s case grammar approach to clause analysis, (Longacre, 1974), I felt it would be helpful to apply his sentence level techniques to the study of Choctaw. Longacre presents a binary, eight-part framework within which he groups all the various types of sentence combinations. [...] I chose to concentrate on the first four deep structures which find their counterparts in formal logic. Basically, conjoining and alternation are non-sequential deep structures while temporal and implication are sequential