Isotropic subbundles of TM⊕T∗MTM\oplus T^*M

We define integrable, big-isotropic structures on a manifold $M$ as subbundles $E\subseteq TM\oplus T^*M$ that are isotropic with respect to the natural, neutral metric (pairing) $g$ of $TM\oplus T^*M$ and are closed by Courant brackets (this also implies that $[E,E^{\perp_g}]\subseteq E^{\perp_g}$). We give the interpretation of such a structure by objects of $M$, we discuss the local geometry of the structure and we give a reduction theorem.Comment: LaTex, 37 pages, minimization of the defining condition

Coupling Poisson and Jacobi structures on foliated manifolds

Let M be a differentiable manifold endowed with a foliation F. A Poisson structure P on M is F-coupling if the image of the annihilator of TF by the sharp-morphism defined by P is a normal bundle of the foliation F. This notion extends Sternberg's coupling symplectic form of a particle in a Yang-Mills field. In the present paper we extend Vorobiev's theory of coupling Poisson structures from fiber bundles to foliations and give simpler proofs of Vorobiev's existence and equivalence theorems of coupling Poisson structures on duals of kernels of transitive Lie algebroids over symplectic manifolds. Then we discuss the extension of the coupling condition to Jacobi structures on foliated manifolds.Comment: LateX, 38 page

Effects of injection pressure on network throughput

©2006 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.Recent parallel systems use multiple injection ports and various injection policies, but little is known about their impact on network performance. This paper evaluates the influence that these injection interfaces have on maximum sustained throughput in adaptive cut-through torus networks by modeling the number of injection queues (1 or 4), and the allocation of new packets to those queues. Network evaluations for medium to large size 2D tori show that designs with multiple injection ports do not improve performance under uniform traffic. On the contrary, they result in more pressure from the injection interface to acquire the scarce network resources of an already clogged system. Interestingly, for small networks, a single injection FIFO queue, with the HOLB it entails, indirectly provides the much needed injection control. For networks with thousands of nodes and multiple injection channels, as those being implemented in current massively parallel processors, this implicit form of congestion control is not enough. In such systems, restrictive injection policies are required to prevent routers from being flooded with new packets for loads beyond saturation.C. Izu, J. Miguel-Alonso, J.A. Gregori

Efficiency and throughput advances in continuous roll-to-roll a-Si alloy PV manufacturing technology: Annual technical progress report: 22 June 1998--21 June 1999

This document reports on work performed by Energy Conversion Devices, Inc. (ECD) during Phase 1 of this subcontract. During this period, ECD researchers: (1) Completed design and construction of new, improved substrate heater; (2) Tested and verified improved performance of the new substrate heater in the pilot machine; (3) Verified improved performance of the new substrate heater in the production machine; (4) Designed and bench-tested a new infrared temperature sensor; (5) Installed a prototype new infrared temperature sensor in the production machine for evaluation; (6) Designed a new rolling thermocouple temperature sensor; (7) Designed and bench-tested a reflectometer for the backreflector deposition machine; (8) Designed and bench-tested in-line non-contacting cell diagnostic sensor and PV capacitive diagnostic system; (9) Installed the in-line cell diagnostic sensor in the 5-MW a-Si deposition machine for evaluation; (10) Demonstrated a new low-cost zinc metal process in the pilot back reflector machine; and (11) Fully tested a new cathode design for improved uniformity

On the design of a high-performance adaptive router for CC-NUMA multiprocessors

Copyright © 2003 IEEEThis work presents the design and evaluation of an adaptive packet router aimed at supporting CC-NUMA traffic. We exploit a simple and efficient packet injection mechanism to avoid deadlock, which leads to a fully adaptive routing by employing only three virtual channels. In addition, we selectively use output buffers for implementing the most utilized virtual paths in order to reduce head-of-line blocking. The careful implementation of these features has resulted in a good trade off between network performance and hardware cost. The outcome of this research is a High-Performance Adaptive Router (HPAR), which adequately balances the needs of parallel applications: minimal network latency at low loads and high throughput at heavy loads. The paper includes an evaluation process in which HPAR is compared with other adaptive routers using FIFO input buffering, with or without additional virtual channels to reduce head-of-line blocking. This evaluation contemplates both the VLSI costs of each router and their performance under synthetic and real application workloads. To make the comparison fair, all the routers use the same efficient deadlock avoidance mechanism. In all the experiments, HPAR exhibited the best response among all the routers tested. The throughput gains ranged from 10 percent to 40 percent in respect to its most direct rival, which employs more hardware resources. Other results shown that HPAR achieves up to 83 percent of its theoretical maximum throughput under random traffic and up to 70 percent when running real applications. Moreover, the observed packet latencies were comparable to those exhibited by simpler routers. Therefore, HPAR can be considered as a suitable candidate to implement packet interchange in next generations of CC-NUMA multiprocessors.Valentín Puente, José-Ángel Gregorio, Ramón Beivide, and Cruz Iz

Distance-hereditary embeddings of circulant graphs

©2003 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.In this paper we present a distance-hereditary decomposition of optimal chordal rings of 2k2 nodes into a set of rings of 2k nodes, where k is the diameter. All the rings belonging to this set have the same length and their diameter corresponds to the diameter of the chordal ring in which they are embedded. The members of this embedded set of rings are non-disjoint and preserve the minimal routing of the original circulant graph. Besides its practical consequences, our research allows the presentation of these optimal circulant graphs as a particular evolution of the traditional ring topology.Carmen Martinez, Beivide Beivide, Jaime Gutierrez, [Maria] Cruz Iz

Illuminating cell signaling with genetically encoded FRET biosensors in adult mouse cardiomyocytes.

FRET-based biosensor experiments in adult cardiomyocytes are a powerful way of dissecting the spatiotemporal dynamics of the complicated signaling networks that regulate cardiac health and disease. However, although much information has been gleaned from FRET studies on cardiomyocytes from larger species, experiments on adult cardiomyocytes from mice have been difficult at best. Thus the large variety of genetic mouse models cannot be easily used for this type of study. Here we develop cell culture conditions for adult mouse cardiomyocytes that permit robust expression of adenoviral FRET biosensors and reproducible FRET experimentation. We find that addition of 6.25 µM blebbistatin or 20 µM (S)-nitro-blebbistatin to a minimal essential medium containing 10 mM HEPES and 0.2% BSA maintains morphology of cardiomyocytes from physiological, pathological, and transgenic mouse models for up to 50 h after adenoviral infection. This provides a 10-15-h time window to perform reproducible FRET readings using a variety of CFP/YFP sensors between 30 and 50 h postinfection. The culture is applicable to cardiomyocytes isolated from transgenic mouse models as well as models with cardiac diseases. Therefore, this study helps scientists to disentangle complicated signaling networks important in health and disease of cardiomyocytes

An Implementation of K-NN Classification Algorithm for Detecting Impersonators in Online Examination Environment

The online examination platforms also known as computer-based testing (CBT) platforms for conducting mass-driven examinations over computer networks to eliminate certain issues such as delay in marking, misplacement of scripts, monitoring, etc., associated with the conventional Pen and Paper Type (PPT) of examination have also been bedeviled with the issue of impersonation commonly associated with the PPT system. The existing online examination platforms rely on passive mechanisms such as the CCTV system and the human invigilators for monitoring the examination halls against cheating and impersonation. The proposed model integrates some level of intelligence into existing online examination prototype by designing and developing an intelligent agent service that could assess students against impersonation threat in an online examination environment using the K-Nearest Neighbor (K-NN) machine learning classification technique considering the level of accuracy and response time in answering the questions. A total of 3,083 dataset was downloaded from an online repository; 80% (2,466) of the dataset was used for training the model, while 20% (617) dataset was used in testing the model to enable the model detect unseen data correctly. Results showed that the developed model has a 99.99% accuracy rate, precision, recall and f-score

Maternal and neonatal vitamin D status at birth in black South Africans

Background. Vitamin D deficiency (VDD) in pregnant women has been associated with adverse pregnancy and neonatal outcomes. 25-hydroxyvitamin D (25(OH)D) levels are affected by numerous factors, including vitamin D intake, skin pigmentation, latitude and season of the year; they therefore vary by race and country. Vitamin D status in pregnant women and their offspring in South Africa (SA) is not well established.Objectives. To assess vitamin D status by measuring serum 25(OH)D in pregnant black SA women and their offspring in Johannesburg (latitude 26°S) and to assess whether vitamin D status is affected by maternal HIV infection.Methods. We prospectively enrolled pregnant women and their healthy neonates, and measured 25(OH)D in maternal and cord blood at delivery. Pregnant women were stratified by their HIV status. Predictors of maternal and neonatal VDD (levels <30 nmol/L) were assessed using multiple logistic regression analysis.Results. A total of 291 pregnant women and their healthy neonates were enrolled over a 21-month period. Mean (standard deviation) maternal and cord blood 25(OH)D levels were 57.0 (29.7) and 41.9 (21.0) nmol/L and the prevalence of VDD was 15.9% and 32.8%, respectively. On average, concentrations of 25(OH)D in cord blood were ~80% of those in the mother. There was no association between cord 25(OH)D and gestational age, but levels were associated with birth weight (p<0.001). There were no differences in maternal or cord blood 25(OH)D levels between those HIV-infected or uninfected. The predictor of VDD in mothers was giving birth in winter (odds ratio (OR) 2.87, 95% confidence interval (CI) 1.47 - 5.61), and in neonates the predictors were maternal age (OR 16.5, 95% CI 1.82 - 149), being born in winter (OR 3.68, 95% CI 2.05 - 6.61), being born by caesarean section (OR 4.92, 95% CI 1.56 - 15.57) and being of low birth weight (OR 1.99, 95% CI 1.13 - 3.50).Conclusions. Among black SA women delivering in Johannesburg, about one in six mothers and one in three neonates have 25(OH)D levels indicative of VDD. Maternal HIV status appears not to affect levels of 25(OH)D in either the mother or her neonate. Research on the effects of VDD on the outcomes of pregnancy and the best methods to combat the high prevalence of VDD in women of childbearing age in the SA context is required

Analysis of network-on-chip topologies for cost-efficient chip multiprocessors

Abstract not availableMarta Ortín-Obón, Darío Suárez-Gracia, María Villarroya-Gaudó, Cruz Izu, Víctor Viñals-Yúfer