A simple demonstration of the existence of the jordan canonical form for any square matrix

All the demonstrations known to this author of the existence of the Jordan Canonical Form aresomewhat complex - usually invoking the use of new spaces, and what not. These demonstrationsare usually too difficult for an average Mathematics student to understand how he or she can obtainthe Jordan Canonical Form for any square matrix. The method here proposed not only demonstratesthe existence of such forms but, additionally, shows how to find them in a step by step manner. I donot claim that the following demonstration is in any way “elegant” (by the standards of elegance infashion nowadays among mathematicians) but merely simple (undergraduate students taking a fistcourse in Matrix Algebra would understand how it works).

Accurate modeling of parallel scientific computations

Scientific codes are usually parallelized by partitioning a grid among processors. To achieve top performance it is necessary to partition the grid so as to balance workload and minimize communication/synchronization costs. This problem is particularly acute when the grid is irregular, changes over the course of the computation, and is not known until load time. Critical mapping and remapping decisions rest on the ability to accurately predict performance, given a description of a grid and its partition. This paper discusses one approach to this problem, and illustrates its use on a one-dimensional fluids code. The models constructed are shown to be accurate, and are used to find optimal remapping schedules

Knee kinematics of total knee replacement patients: pre and post operative analysis using computer generated images

This project aims to show a comparison of knee kinematics in pre- and post-operative knee replacement surgery, using computer animation to represent a patient specific model of the knee joint interactions under every day conditions

Proteomics reveals that a high-fat diet induces rapid changes in hypothalamic proteins related to neuronal damage and inflammation

Peer reviewedPublisher PD

Designed-in security for cyber-physical systems

An expert from academia, one from a cyber-physical system (CPS) provider, and one from an end asset owner and user offer their different perspectives on the meaning and challenges of 'designed-in security.' The academic highlights foundational issues and talks about emerging technology that can help us design and implement secure software in CPSs. The vendor's view includes components of the academic view but emphasizes the secure system development process and the standards that the system must satisfy. The user issues a call to action and offers ideas that will ensure progress

High pressure cosmochemistry applied to major planetary interiors: Experimental studies

The overall goal of this project is to determine properties of the H-He-C-N-O system, as represented by small molecules composed of these elements, that are needed to constrain theoretical models of the interiors of the major planets. Much of our work now concerns the H2O-NH3 system. This project is the first major effort to measure phase equilibria in binary fluid-solid systems in diamond anvil cells. Vibrational spectroscopy, direct visual observations, and X-ray crystallography of materials confined in externally heated cells are our primary experimental probes. We also are collaborating with the shockwave physics group at Lawrence Livermore Laboratory in studies of the equation of state of a synthetic Uranus fluid and molecular composition of this and other H-C-N-O materials under planetary conditions

Examining affective structure in chickens: valence, intensity, persistence and generalization measured using a conditioned place preference test

When measuring animals’ valenced behavioural responses to stimuli, the Conditioned Place Preference (CPP) test goes a step further than many approach-based and avoidance-based tests by establishing whether a learned preference for, or aversion to, the location in which the stimulus was encountered can be generated. We designed a novel, four-chambered CPP test to extend the capability of the usual CPP paradigm to provide information on four key features of animals’ affective responses: valence, scale, persistence and generalization. Using this test, we investigated the affective responses of domestic chickens (Gallus gallus domesticus) to four potentially aversive stimuli: 1. Puffs of air; 2. Sight of (robotic) snake; 3. Sprays of water; 4. Sound of conspecific alarm calls. We found conditioned avoidance of locations associated with the air puffs and water sprays (Friedman’s χ2(3) = 13.323 p > .005; χ2(3) = 14.235 p > .005), but not with the snake and alarm calls. The scale of the learned avoidance was similar for the air puff and water spray stimuli, but persistence and generalization differed. We conclude that the four chambered CPP test can have a valuable role to play in making multi-feature measurements of stimulus-generated affective responses, and we highlight the value of such measurements for improving our understanding of the structure of affect in chickens and other animals

Loi de position ou durée vocalique?

Cet article défend la « loi de position », selon laquelle les voyelles françaises en syllabe fermée tendent à s’ouvrir, et les voyelles en syllabe ouverte, à se fermer, contre les arguments de Y.-C. Morin, pour qui la qualité des voyelles françaises se rapporte surtout à leur longueur en français moyen. Il est admis que si elle rend mieux compte du vocalisme de certains parlers français que la thèse de Morin, la soi-disante « loi » admet beaucoup d’exceptions en français académique. On peut pourtant dire la même chose de l’hypothèse Morin, et la « loi » se situe d’ailleurs sur un plan différent, puisqu’elle se rapporte au devenir de la langue, plutôt qu’à son état contemporain.The "loi de position", according to which French vowels tend to open in closed syllables, and close in open ones, is defended against Y.-C. Morin's view that the quality of French vowels is above all related to their length in Middle French. It is admitted that although the "law" accounts more satisfactorily for the vowel-system of some French parlers, there are still many exceptions to it in contemporary standard French. However, the same is true of Morin's hypothesis, and in any case, the "law" operates on a different plane, since it relates to a continuing movement within the language, rather than to its present state