Structured Parallel Architecture for Displacement MIMO Kalman Equalizer in CDMA Systems

A reduced complexity MIMO Kalman equalizer architecture is proposed in this brief by jointly considering the displacement structure and the block-Toeplitz structure. Numerical matrix-matrix multiplications with O(F³) complexity are eliminated by simple data loading process, where F is the spreading factor. Finally, an iterative Conjugate-Gradient based algorithm is proposed to avoid the inverse of the Hermitian symmetric innovation covariance matrix in Kalman gain processor. The proposed architecture not only reduces the numerical complexity from O(F²) to O(Flog₂F) per chip, but also facilitates the parallel and pipelined VLSI implementation in real-time processing     

Poly(amidoamine) dendrimers as nanoscale diffusion probes in sol-gel films investigated by total internal reflection fluorescence spectroscopy

Three generations of poly(amidoamine) dendrimers were dye-labeled and chemically modified to have terminal carboxyl groups and used as variably sized probes to study diffusion in thin sol-gel films. Total internal reflection fluorescence spectroscopy experiments, both correlation and concentration-jump measurements, were employed to measure the relative populations and effective diffusion coefficients of dendrimers in the films. For films prepared from small (27-nm) silica particles, larger dendrimers could be completely excluded from penetrating the sol-gel structure. In films made of larger (150-nm) particles with correspondingly larger pores, concentration-jump experiments showed that larger dendrimers are excluded from more of the intraparticle pore space than small dendrimers. Similarly, fluorescence-correlation measurements showed that the diffusion of smaller dendrimers exhibited greater tortuosity than larger dendrimers in the interparticle pores of the film. The smaller dendrimers explore a greater volume of smaller, more convoluted pores, whereas larger dendrimers penetrate a smaller volume of larger, more open pores.     

A review of autoimmune disorders anecdotally linked to mammary implants

Autoimmune disorders lead to a sequence of tissue reactions and damage that may produce diffuse, systemic signs and symptoms. Litigants in many breast implants trials have claimed their autoimmune disorders (rheumatoid arthritis, scleroderma, and SLE) were from a causal relationship with mammary implants. Science suggests environmental factors, such as vinyl chloride, and hereditary factors may account for some of the prevalence of these disorders, however the exact cause remains a mystery and brings into question the claims being brought by litigants regarding implants.     

The depolymerization of low molecular weight poly(chloroacetaldehydes)

Stability of low molecular weight (D.P. < 300) polychloral has been found to be a function of the amine used as the polymerization initiator. The polymer produced with diethylamine unzips much more rapidly than that made with triethylamine. This investigation also showed that ester endcaps provide little protection from amine-induced depolymerization. The amine-initiated copolymer of chloral and dichloroacetaldehyde behaves anomalously in that it is unstable in the presence of normally inert organic solvents. Mechanisms are proposed to account for these observations.     

Comparison of one-way and shuttle-avoidance performance of gerbils and rats.

Compared the avoidance probability of 10 male and 10 female Long-Evans rats and an equal number of gerbils in a l-way and in a shuttle task. Rats in the shuttle task, especially males, had lower avoidance probabilities than gerbils possibly reflecting a species difference in the response hierarchy in the shuttle task. It is suggested that the lower avoidance probabilities of rats may be attributable to the displacement of the flight response by other species-specific defense reactions (SSDRs) induced by the impossibility in the shuttle task of physically escaping the site of noxious stimulation. The uniformity of gerbil avoidance probability across sex and task suggests that the impossibility of fleeing the location of noxious stimuli does not alter the hierarchy of SSDRs in the gerbil. (17 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On the dynamics and control of through-plane water distributions in PEM fuel cells

We provide a semi-analytic solution to simplify an experimentally validated numeric realization of a two-phase, reaction-diffusion, distributed parameter model of the through-plane water distributions as they evolve inside polymer electrolyte membrane (PEM) fuel cell gas diffusion layers. The semi-analytic solution is then analyzed for stability and to gain insight into the dynamics of the equilibrium (steady-state) water distributions. Candidate distributions for vapor and liquid water are then identified which allow maximum membrane hydration while simultaneously avoiding voltage degradation that results from anode liquid water accumulation (flooding). The desired anode water distributions could be maintained via control of the anode channel conditions (boundary value control) with the ultimate goal to maximize the hydrogen utilization and prolong fuel cell life.     

An application example of the NBS robot control system

The National Bureau of Standards, Industrial Systems Division, has designed The Robot Control System where high level goals are decomposed through a succession of levels, each producing strings of simpler commands to the next lower level. The bottom level generates the drive signals to the robot, gripper, and other actuators. Each control level is a separate process with a limited scope of responsibility, independent of the details at other levels, thus providing a foundation for future modular, “plug compatible” hardware and software for robotics and other real-time sensory interactive control applications.To aid in specifying the required task decomposition and task processing, a programming language and program developing environment have been implemented. Programs at each control level are expressed as state tables, and the programming environment permits the generation, editing, emulation, and evaluation of these state tables. The control system is completely interactive, allowing the system to run freely, or be single-stepped to any level of detail.This paper describes the first application of The NBS Robotol Control System in a realistic factory environment, fully integrated with a workstation control system, database system, safety computer, gripper control system, vision system, and network.     

Citation context analysis and aging patterns of journal articles in molecular genetics

To compare citation history and contextual importance, eleven highly cited articles, 4 slowly aging (Type 1) and 7 quickly aging (Type 2), were ranked using an aggregate citation context measure, the Mean Utility Index. Based on citations in late (PY 6 & 7) source articles, methods papers consistently ranked higher than papers cited for research results and theoretical implications, and Type 1 methods papers ranked above all Type 2 papers. A Type 1 paper representing an important theoretical concept could not be distinguished from Type 2 papers using citation context alone.     

Static two-dimensional aperture coding for multimodal, multiplex spectroscopy

We propose a new class of aperture-coded spectrometer that is optimized for the spectral characterization of diffuse sources. The instrument achieves high throughput and high spectral resolution by replacing the slit of conventional dispersive spectrometers with a more complicated spatial filter. We develop a general mathematical framework for deriving the required aperture codes and discuss several appealing code families. Experimental results validate the performance of the instrument.