Dynamical consistency in hierarchical supervisory control

A hierarchical control theory is presented founded upon the trace-dynamical consistency property, which is an extension of the notion of dynamical consistency (DC) to the supervisory case of automata with disablable transitions. Partitions of a system state space are considered for which both the trace-DC and the (non-blocking) in-block controllability (IBC) conditions hold; it is shown that low-level non-blocking controllable languages project up to such languages in the high-level system, and that, when the (non-blocking) IBC condition also holds, high-level non-blocking controllable languages map down to such languages in the low-level system. It is demonstrated that the resulting pairs of low-level and high-level languages satisfy a version of the hierarchical consistency condition found in the existing language-based hierarchical supervisory control theory. The structures produced in the formulation of hierarchical control in this paper permit efficient regulator design (and, in particular, repeated re-design) for hierarchy-compatible language specifications; such specifications consist of low-level languages whose maximal controllable sublanguages are realizable by a combination of a high-level (possibly history-dependent) regulator and a set of (state-dependent) low-level regulators (specified block-wise). An algorithm is proposed which facilitates the construction of (non-blocking) IBC partitions of systems with vocalized states. Examples are presented, including a material transfer line with re-entrant flow and a double queue     

Microstructure and Crystallography of Titanium Nitride Whiskers Grown by a Vapor–Liquid–Solid Process

Titanium nitride whiskers having diameters of 0.5 to 1.5 μm and aspect ratios in the range of 20 to 50 have been produced by a new commercially scalable vapor–liquid–solid process. Electron microscopy studies have shown that most of the whiskers can be classified into two types based upon structure and morphology. The whiskers of one type are single crystals and have a growth direction of (100). Whiskers of the second type are comprised of two crystals having a common (110) growth direction. Both types have smooth surfaces and relatively few internal defects. Additionally, a small percentage of whiskers have considerable internal structure related to significant magnesium impurities.     

Sunflower and safflower seeds and oils

Summary Chemical analyses of sunflower and safflower seeds, the hulled seed, and the hulls and oils have been made. The 28 samples of sunflower seed, representing four varieties grown at seven locations, contained an average of 29% oil which was composed chiefly (51 to 68%) of linoleic acid glycerides. The eight varieties of safflower seeds grown at Huntley, Montana, contained an average of 33% oil, with an average content of 78% linoleic glycerides. Data on the amounts of ash, nitrogen, sugar, as well as oil, are presented for the whole seeds and their fractions. Paper presented at the 19th fall meeting of the American Oil Chemists’ Society, Chicago, Nov. 7–9, 1945. This is one of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U. S. Department of Agriculture.     

Stress-induced structural changes in La-doped BiFeO3–PbTiO3 high-temperature piezoceramics

High-temperature piezoelectric polycrystalline ceramics of the system (1 ? x)(Bi_1?yLa_y)FeO₃-xPbTiO₃ (BF–PT), which are mixed phase in their consolidated state, have been investigated by in situ neutron diffraction during the application of uniaxial compressive stress. It is suggested that the achievable strain in BF–PT is largely generated by straining of the rhombohedral phase. The results of the neutron diffraction measurements are compared and discussed with respect to the measured macroscopic ferroelastic constitutive behavior for various compositions of BF–PT.     

Progress in the development of a high average power ultra-broadbandinfrared radiation source

This paper describes numerical and analytical studies on the optimization of the ultra-broadband infrared (IR) source, a novel high average-power device. The main objective of current studies was the reduction of weight, size, and cost of the system by devising a scheme to generate the two closely spaced radiation lines with a single laser driver instead of the two CO₂ transversely excited atmospheric pressure (TEA) lasers envisioned in the initial work. By inducing the modulation instability in nonlinear media, we have obtained as good or better results as in our previous studies but with one of the TEA lasers replaced by a very low-power driver that provides the seed radiation for the excitation of the instability. Even more importantly, we have demonstrated that the second high peak-power TEA laser can be replaced by a compact, light weight, low peak-power driver by focusing the radiation to a tighter spot. The average power of the source is maintained at the previous level by operating at higher duty factor. In the new low-peak-power operating regime, the output spectrum is very similar to that of the high-power regime, provided that the ratio of the peak power to the nonlinear length that scales proportionally to the area of the laser spot remains fixed     

A principal components analysis of dynamic spatial memory biases.

Research has shown that spatial memory for moving targets is often biased in the direction of implied momentum and implied gravity, suggesting that representations of the subjective experiences of these physical principles contribute to such biases. The present study examined the association between these spatial memory biases. Observers viewed targets that moved horizontally from left to right before disappearing or viewed briefly shown stationary targets. After a target disappeared, observers indicated the vanishing position of the target. Principal components analysis revealed that biases along the horizontal axis of motion loaded on separate components from biases along the vertical axis orthogonal to motion. The findings support the hypothesis that implied momentum and implied gravity biases have unique influences on spatial memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Graphene synthesis by ion implantation

We demonstrate an ion implantation method for large-scale synthesis of high quality graphene films with controllable thickness. Thermally annealing polycrystalline nickel substrates that have been ion implanted with carbon atoms results in the surface growth of graphene films whose average thickness is controlled by implantation dose. The graphene film quality, as probed with Raman and electrical measurements, is comparable to previously reported synthesis methods. The implantation synthesis method can be generalized to a variety of metallic substrates and growth temperatures, since it does not require a decomposition of chemical precursors or a solvation of carbon into the substrate.     

The dyadic nature of social information processing in boys' reactive and proactive aggression.

The correlation between boys' social cognitions and their aggressive behavior toward peers was examined as being actor driven, partner driven, or dyadic relationship driven. Eleven groups of 6 familiar boys each (N?=?165 dyads) met for 5 consecutive days to participate in play sessions and social-cognitive interviews. With a variance partitioning procedure, boys' social-cognitive processes were found to vary reliably across their dyadic relationships. Furthermore, mixed models regression analyses indicated that hostile attributional biases toward a particular peer were related to directly observed reactive aggression toward that peer even after controlling for actor and partner effects, suggesting that these phenomena are dyadic or relationship oriented. On the other hand, the relation between outcome expectancies for aggression and the display of proactive aggression appeared to be more actor driven and partner driven that dyadic. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fluorescent tissue site-selective lanthanide chelate, Tb-PCTMB for enhanced imaging of cancer.

In-vivo and in-vitro investigations indicate that a newly developed polyazamacrocyclic chelate of Tb(III) has superior properties for use as an abnormal tissue marker. In addition to tissue selectivity, this molecule is unique because of its low toxicity, attractive fluorescent properties, rapid pharmokinetics, and relatively high water solubility. The complex Tb-3,6,9-tris(methylene phosphonic acid n-butyl ester)-3,6,9,15-tetraazabicyclo[9.3.1]-pentadeca-1(15),11,13 -triene (Tb-PCTMB) has also been shown to exhibit strongly shifted emission (delta lambda--280 nm), moving the detection frequency away from autofluorescence backgrounds, and good quantum efficiencies (phi = 0.51), providing high brightness. Fluorescence imaging was used to quantify Tb-PCTMB at the picomolar level in tissues and to show the significant difference in affinity for the chelate by adenocarcinoma cells HT-29 versus normal epithelial cells (IEC-6). Topical application, or lavage introduction, under endoscopy was used to instill a millimolar aqueous solution of Tb-PCTMB into a dimethylhydrizene-treated Sprague Dawley rat large intestine containing a suspect growth. Subsequent in vitro fluorescence detection and standard histological evaluation confirmed enhanced uptake by adenocarcinoma tissue. Semiquantitative signal interrogation was employed to show the potential for using Tb-PCTMB as a contrast enhancement marker for disease detection.     

Medical Data Mining on the Internet: Research on a Cancer Information System

This paper discusses several data mining algorithms and techniques thatwe have developed at the University of Arizona Artificial Intelligence Lab.We have implemented these algorithms and techniques into severalprototypes, one of which focuses on medical information developed incooperation with the National Cancer Institute (NCI) and the University ofIllinois at Urbana-Champaign. We propose an architecture for medicalknowledge information systems that will permit data mining across severalmedical information sources and discuss a suite of data mining tools that weare developing to assist NCI in improving public access to and use of theirexisting vast cancer information collections.