Generic canonical form of pairs of matrices with zeros

We consider a family of pairs of m-by-p and m-by-q matrices, in which some entries are required to be zero and the others are arbitrary, with respect to transformations (A,B)--> (SAR,SBL) with nonsingular S, R, L. We prove that almost all of these pairs reduce to the same pair (C, D) from this family, except for pairs whose arbitrary entries are zeros of a certain polynomial. The polynomial and the pair (C D) are constructed by a combinatorial method based on properties of a certain graph.Comment: 13 page

Real-Time Measurement of Thin Film Thickness During Plasma Processing

An in situ single point two-color laser interferometer is used to monitor in real-time the thickness of thin transparent films during processing. The instantaneous change of film thickness is determined by comparing the measured laser reflection interference to that calculated by a model. The etch or deposition rates of the film are determined within 1–2 seconds. The film thickness is also determined in real-time from the phase difference of the reflected laser intensity between the two laser colors. Use of two-color laser interferometry improves the accuracy of the calculated etch or growth rates of the film considerably. Moreover, the two colors provide a clear distinction between film etching and deposition, which may often occur during the same process, and can not be determined by a single color interferometer. The uniformity of the film's etch or deposition rates across the substrate is monitored by an in situ full-wafer image interferometer. The combined use of these two sensors provide instantaneous information of the film thickness, etch or growth rates, as well as time averaged uniformity of the process rates. This diagnostic setup is very useful for process development and monitoring, which is also suitable for manufacturing environment, and can be used for real-time process control.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45461/1/11088_2004_Article_412642.pd

Plasma Characterization of Hall Thruster with Active and Passive Segmented Electrodes

Non-emissive electrodes and ceramic spacers placed along the Hall thruster channel are shown to affect the plasma potential distribution and the thruster operation. These effects are associated with physical properties of the electrode material and depend on the electrode configuration, geometry and the magnetic field distribution. An emissive segmented electrode was able to maintain thruster operation by supplying an additional electron flux to sustain the plasma discharge between the anode and cathode neutralizer. These results indicate the possibility of new configurations for segmented electrode Hall thruster

Forensic interviewing of mentally disordered suspects: The impact of interview style on investigation outcomes.

The investigative interviewing of a vulnerable suspect is a complex and difficult task. Current best practice advocates for the use of open questions in order to elicit a free recall. However, those with mental health conditions have limited cognitive abilities that relate to free recall and episodic memory, and there is emerging evidence that suggests open questions may not always be most suitable for the vulnerable interviewee. As such, the present study examined the impact of two different interview models (best practice v modified interview) on the amount and accuracy of investigation relevant information obtained within an experimental vulnerable ‘suspect’ sample. Participants engaged in two tasks; a minor transgression and a matched non-transgression. Each participant was then subject to either a best practice (containing largely open questions) or a modified interview (containing largely closed questions). Vulnerable participants provided a significantly higher and more accurate amount of investigation relevant information during the modified interview rather than the best practice interview. In addition, participants that have mental health conditions sought more clarifications during the best practice interviews. The type of interview did not impact upon the level of vulnerability displayed. Our findings challenge current best practice in that vulnerable participants performed worse in interviews containing more open questions than closed questions. These findings add to the emerging evidence base that vulnerable individuals may require an alternative method of questioning, including the use of closed questions as ‘scaffolding’ during an investigative interview