3,321 research outputs found
ARTMAP-DS: Pattern Discrimination by Discounting Similarities
ARTMAP-DS extends fuzzy ARTMAP to discriminate between similar inputs by discounting similarities. When two or more candidate category representations are activated by a given input, features that the candidate representations have in common are ignored prior to determining the winning category. Simulations illustrate the network's ability to recognize similar inputs, such as STAR and START, in a noisy environment.National Science Foundation (IRI-94-01659); Office of Naval Research (N00014-95-1-0409, N00014-95-1-0657
Group algebras and enveloping algebras with nonmatrix and semigroup identities
Let K be a field of positive characteristic p, let R be either a group
algebra K[G] or a restricted enveloping algebra u(L), and let I be the
augmentation ideal of R. We first characterize those R for which I satisfies a
polynomial identity not satisfied by the algebra of all 2-by-2 matrices over K.
Then we examine those R for which I satisfies a semigroup identity (that is, a
polynomial identity which can be written as the difference of two monomials).Comment: 11 pages. Written in LaTeX2
An Investigation of Void Fraction in the Stratified/Annular Flow Regions in Smooth, Horizontal Tubes
Refrigerants R134a and R410A have been used for void fraction measurements in smooth
horizontal tubes with diameters between 4mm and 7mm. Quality and mass flux were varied from
5% to 90% and 75 kglm2-s to 700 kglm2-s, respectively. Two test loops, one for condensing
flows at 35C and the other for evaporating flows at 5C, were used in the investigation. Results
show that near the transition from annular to stratified flow void fraction changed from viscousinertial
dependence to gravitational-inertial dominated dependence. An important feature
observed is the annular flow region's relative insensitivity to mass flux while the border region
between annular and stratified flows is characterized by strong mass flux dependence.Air Conditioning and Refrigeration Project 7
The impact of CoRoT on close binary research
The space experiment CoRoT will provide continuous monitoring and high
accuracy light curves of about sixty thousand stars. Selected binary systems
will be observed in the Additional Program frame as targets of long and
continuous pointed observations. Moreover, thousands of new binaries will
certainly be detected and hundreds of them will have extremely accurate light
curves. This will allow studies of fine effects on the light curves, monitoring
of stellar activity and, in combination with ground-based observations, will
provide exquisite determination of stellar parameters.
Among the new discoveries of interesting systems of special value will be
those of low mass binaries.Comment: 6 pages, 2 figures, contribution to "Colse binaries in the 21th
century", Syros (Greece), June 2005. To be published by Ap&S
Monoxenic culture of the slug parasite Phasmarhabditis hermaphrodita (Nematoda : Rhabditidae) with different bacteria in liquid and solid phase
Seize isolats bactériens, représentant treize espÚces, ont été testés pour leur capacité à maintenir la croissance de #Phasmarhabditis hermaphrodita en culture monoxénique sur agar, en boßte de Petri. Tous les isolats permettent la croissance de #P. hermaphrodita, mais la capacité de reproduction varie considérablement suivant les différentes bactéries. Cinq espÚces de bactéries ayant permis une croissance vigoureuse de #P. hermaphrodita ont été utilisées pour son élevage en milieu liquide. Toutes permettent la croissance et la reproduction du nématode mais des différences significatives se produisent en ce qui concerne le nombre total de nématodes et celui des #dauer larvae formées. Les différences entre les chiffres totaux ne sont pas significativement différentes de celles observées dans le cas de culture en boßtes de Petri. En milieu liquide, #Providencia rettgeri paraßt produire les meilleurs rendements en #dauer larvae. Tant en milieu solide que liquide, la croissance monoxénique de #P. hermaphrodita$ est meilleure sur des milieux à base de rognon de porc que sur des milieux ne comportant que des éléments entiÚrement solubles. (Résumé d'auteur
ATTENUATION OF GROUND REACTION FORCES IN DISMOUNTS FROM TEH BALANCE BEAM
Epidemiological studies have documented the incidence of injuries in female gymnasts . In comparison to other sports, the incidence of injury in gymnastics is high relative to other sports. One epidemiology study prompted the author to state that "...women's gymnastics should he recognized as a hazardous sport." To understand the etiology 01 injury, researchers have identified injuries by sites, types and/or events (floor, uneven bars, vault, and balance beam). Dismounts, considered an element 01 all events, have drawn attention as an injury mechanism. Studies have shown he dismount, especially when gymnasts attempt to "stick" their lauding, to be a major component of the incidence of injury. This study investigated ground reaction forces in the dismount from the balance beam under two styles (stick and roll-out of the landing). Attenuation of relatively high impact forces through modification of landing may be used, at minimum, in practices to reduce the exposure to gymnasts to this physical contraindication. Subjects were 23 female gymnasts who ranged in age (118 to 201 months, mean=158.8, SD=23.7) and level (5 to 10). Each subject was asked to perform two types of dismounts (roundoff and barani) from a balance beam and to land each dismount with two the different styles onto a mot adhered to a force platform. AU subjects had ground reaction forces for both styles of the roundoff. and 14 subjects had ground reaction forces for both styles of the barani dismount. Table 1 contains a summary of the ground reaction forces as a percentage of body weight. Our results indicate that vertical ground reaction forces are significantly reduced by rolling out of the landing
Evacuation planning in the Auckland Volcanic Field, New Zealand: a spatio-temporal approach for emergency management and transportation network decisions
Auckland is the largest city in New Zealand (pop. 1.5 million) and is situated atop an active monogenetic volcanic
field. When volcanic activity next occurs, the most effective means of protecting the people who reside and work
in the region will be to evacuate the danger zone prior to the eruption. This study investigates the evacuation
demand throughout the Auckland Volcanic Field and the capacity of the transportation network to fulfil such a
demand. Diurnal movements of the population are assessed and, due to the seemingly random pattern of
eruptions in the past, a non-specific approach is adopted to determine spatial vulnerabilities at a micro-scale (neighbourhoods).
We achieve this through the calculation of population-, household- and car-to-exit capacity ratios. Following
an analysis of transportation hub functionality and the susceptibility of motorway bridges to a new eruption,
modelling using dynamic route and traffic assignment was undertaken to determine various evacuation attributes
at a macro-scale and forecast total network clearance times. Evacuation demand was found to be highly correlated
to diurnal population movements and neighbourhood boundary types, a trend that was also evident in the evacuation
capacity ratio results. Elevated population to evacuation capacity ratios occur during the day in and around
the central city, and at night in many of the outlying suburbs. Low-mobility populations generally have better than
average access to public transportation. Macro-scale vulnerability was far more contingent upon the destination of
evacuees, with favourable results for evacuation within the region as opposed to outside the region. Clearance
times for intra-regional evacuation ranged from one to nine hours, whereas those for inter-regional evacuation were
found to be so high, that the results were unrealistic. Therefore, we conclude that, from a mobility standpoint, there
is considerable merit to intra-regional evacuation
Best practice for collar deployment of tri-axial accelerometers on a terrestrial quadruped to provide accurate measurement of body acceleration
Background: Tri-axial accelerometers are frequently deployed on terrestrial quadrupedal mammals using collars, because they are easy to fit and are thought to have minimal impact on the subject. Collar-attached devices are not fixed to the body and can move independently of the body. This may result in inaccurate measures of acceleration, reducing the accuracy of measured body movement. We determined the effect of collar size and collar weight on acceleration measured by a collar-mounted accelerometer on a quadruped mammal. The aim was to suggest best practice for sizes and weights of collars on which to deploy tri-axial accelerometers. Using pygmy goats, Capra aegagrus hircus, which were trained to walk at different speeds (0.8â3.0 km/h) on a treadmill, we measured body acceleration using a collar-mounted tri-axial accelerometer, with different collar sizes (individual neck circumference +â1 cm to +â9 cm) and collar weight (0.4% to 1.2% of individual weight). Results: There was a significant effect of collar size, collar weight and walking speed on measured acceleration. Measured acceleration was less accurate and more variable when collars were looser and heavier. To measure body acceleration more accurately, we found that collar size should be within 5 cm or 16% of an individualâs neck circumference when it was heavy (up to 1.2% of animalâs body weight) or within 7 cm (33%) of neck circumference if the collar was light (up to 0.6% of animal body weight). Conclusion: We suggest that not only reporting collar size and weight for welfare purposes, but it is also important to consider these aspects for scientific rigour, to ensure data are collected as accurately as possible. We provide guidelines for researchers fitting collar-attached devices to ensure a higher degree of accuracy of recorded body acceleration
Recommended from our members
Rapid Casing Corrosion in High Temperature Liquid Dominated Geothermal Fields
Downhole logging and workover operations on 12-20 year old wells in several high temperature, liquid-dominated geothermal fields in New Zealand has shown that severe corrosion has commonly occurred in the production casing string where this is unprotected by larger diameter casings. To date corrosion products from only one well have been examined in detail. These indicate that corrosion attack commences at the outer casing wall and continues at a rate as great as 0.8mm/year. Rapid corrosion has been attributed to neutral or slightly acid high bicarbonate waters formed by the absorption of steam and gas into shallow aquifers not directly connected to the deeper, high chloride reservoir
Disentangling effective temperatures of individual eclipsing binary components by means of color-index constraining
Eclipsing binary stars are gratifying objects because of their unique
geometrical properties upon which all important physical parameters such as
masses, radii, temperatures, luminosities and distance may be obtained in
absolute scale. This poses strict demand on the model to be free of systematic
effects that would influence the results later used for calibrations, catalogs
and evolution theory. We present an objective scheme of obtaining individual
temperatures of both binary system components by means of color-index
constraining, with the only requirement that the observational data-set is
acquired in a standard photometric system. We show that for a modest case of
two similar main-sequence components the erroneous approach of assuming the
temperature of the primary star from the color index yields temperatures which
are systematically wrong by ~100K.Comment: 6 pages, 3 figures, 1 table; to appear in proceedings of the Close
Binaries in the 21st Century conference in Syros, Greec
- âŠ