When sharing information, a common tactic for reducing the cost of choosing recipients is to form
named groups
of users. These groups are then selected as recipients in lieu of or in addition to ...users. However, keeping named groups up to date is a difficult and error-prone task when conducted manually. Past schemes automating this task make different tradeoffs and can be distinguished based on several factors including the types of named groups they consider, whether they evolve a specific group or a set of multiple groups, and how integrated they are with techniques for predicting initial groups. We analyze these approaches and identify a design space of potential evolutionary approaches. Using this analysis, we introduce a novel approach for automatically suggesting a sub-type of evolution, evolutionary growth. This approach (a) requires no prior knowledge of which groups change, (b) composes, and therefore interoperates, with an existing engine for recommending named groups, and (c) extracts groups from the social graph of multiple types of applications regardless of whether the graph are explicit or derived implicitly from message communication. Our evaluation considers social graphs created using explicit and implicit connections, and identifies the conditions under which the approach outperforms baseline techniques.
The authors previously prepared a model of coherent acoustic reflection loss at the ocean surface by combining a model of surface roughness loss with determination of surface incidence angle that ...accounted for the refractive effects of a uniformly stratified distribution of wind-driven bubbles. Originally, the surface roughness loss was based on a second-order small-slope approximation and the surface incidence angle was obtained using an exact solution for propagation of the incident acoustic plane wave in a layer of particular sound-speed variation. In this paper, the previous solution for surface incidence angle is simplified with the assumption that the grazing angle at the bottom of the layer is small. An approximate solution for the surface grazing angle is found in terms of grazing angle below the layer and a polynomial series in a derived parameter, which in turn is a function of wind speed and acoustic frequency. This determination of surface angle is combined with a simplified model of surface roughness loss to produce a complete model suitable for use with ray-type transmission calculations or hand calculations. The resulting model permits the prediction of the coherent surface reflection loss with only wind speed and frequency as input parameters. Results from the use of this approximated model with a Gaussian beam acoustic propagation code are compared with predictions based on Monte Carlo parabolic equation transmission calculations for surface ducted scenarios including various levels of roughness. The zones of validity of the model are considered at length.
Agricultural drainage water is a complex mixture of dissolved and suspended chemical species and may contain a wide variety of microorganisms. The application of membrane systems for desalination of ...agricultural drainage (AD) water requires careful consideration of feed water quality, suitable membrane selection and operating conditions. In order to evaluate the potential applicability of low-pressure reverse osmosis (RO) to the treatment of AD water, a diagnostic approach to membrane selection and process evaluation was undertaken in support of a pilot field study in the California San Joaquin Valley. Five candidate membranes were evaluated in a diagnostic laboratory membrane system which provided an initial selection based on salt rejection and product water flux performance for model salt solutions of univalent and divalent cations. Biofouling potential of the selected membranes was also evaluated using two standards strains of bacteria. Preliminary pilot plant performance, based on the selected membranes, was encouraging and has provided the basis for long-term pilot plant testing at higher recoveries to assess the impact of fluctuating AD water feed composition.
The accurate modeling of underwater acoustical reflection from a wind-roughened ocean surface is a challenging problem. Some complicating factors are the presence of near-surface bubbles and the ...potential for shadowing of acoustical energy by parts of the surface itself. One essential factor, which is the subject of this paper, is the specular reflection of coherent plane waves at an ocean-like rough surface. We tested the accuracy of one rough surface reflection model, the small-slope approximation (SSA) approach as used by Williams (J. Acoust. Soc. Amer., vol. 116, no. 4, pp. 1975-1984, Oct. 2004), for scenarios for which scattering was entirely in the vertical plane. The SSA model was used to compute values of the coherent plane wave reflection loss per bounce for wind speeds between 5 and 12.5 m/s, frequencies between 1.5 and 9 kHz, and grazing angles between about 1 ° and 10 ° . These values were compared to those obtained from a Monte Carlo approach based on the parabolic equation (PE) method, where realistic ocean surfaces were generated based on the Pierson-Moskowitz spectrum for ocean surface heights. The SSA model compared favorably with the more rigorous PE method for most of the range of parameters considered. An approximation to the SSA model was derived for application to grazing angles less than particular values, and this approximation was shown to compare well with results from PE modeling.
To examine the comparative efficacy of 3 common measures of traumatic brain injury (TBI) severity for predicting inpatient outcomes upon hospital discharge.
Acute brain injury rehabilitation unit at ...level 1 trauma center.
100 patients with TBI.
Retrospective analysis of injury severity, demographic, and outcome data.
Glasgow Coma Scale (GCS) at admission, time to follow commands (TTC), duration of posttraumatic amnesia (PTA), and Functional Independence Measure at hospital discharge.
A hierarchal multiple regression revealed that duration of PTA was a significant and powerful unique predictor of Functional Independence Measure scores at discharge (β = -0.46, P = .001), while TTC (β = 0.26, P = .056) and GCS (β = 0.16, P = .143) were not. These effects were present even after controlling for age, gender, educational level, racial/ethnic minority status, cause of injury, history of substance abuse, and neurosurgical intervention.
Although clinicians often use GCS scores and TTC when assessing acute TBI severity and during treatment formulation, this study provides evidence that duration of PTA may be a more meaningful predictor of patients' functional levels at discharge.
Coppicing is a commonly used management intervention to increase structural diversity in woodlands, but coppiced trees are vulnerable to browsing by deer. We investigated the effect of coppicing ...hazel stools at different heights on the survival of trees, and also the species richness of the ground flora. Plots were cut at experimental heights of 0.7 m and 0.8 m, with plots cut at 1.2 m and ground level as controls. All the stools cut at 1.2 m were alive five years after cutting. In the plots cut at 0.7 and 0.8 m, some shoots were eaten by deer but less than 10% of stools died. Less than 5% of stools in the plot cut at ground level survived. After 7–8 years, coppicing at 0.7 m and 0.8 m supported a higher species richness of angiosperm ground flora than either of the control heights. We conclude that high-level coppicing offers a costeffective opportunity to achieve a rotation frequency that increases tree survival and supports a diverse coppice-woodland angiosperm flora.
Cracks in Multilayer Capacitors are often latent defects, which are not recognized in production, but can cause substantial problems in field. Therefore it is important to find possibilities to ...detect those candidates before delivering electronic equipment.
In this work, cracked capacitors were characterized by electrical parameter testing and by piezoelectric spectroscopy. As a new method, sound emission spectroscopy was employed as indicator for latent defects and correlated with electrical data and physical analysis. The results show that sound emission used on a statistical basis and piezoelectric response might be effective to screen latent defects in electronic control units.
Green Anoles (Anolis carolinensis) are comprised of red-dewlapped (RD) forms that are found throughout the southeastern USA and a gray-dewlapped (GD) form that is restricted to southwest Florida. ...Prior research has shown that RD A. carolinensis produce headbob displays of three distinct types that differ primarily in their temporal patterns. Based on known morphological, physiological, and genetic differences between GD and RD populations, we hypothesized that these populations also would differ in headbob display structure. To test this hypothesis we quantified 440 displays from 39 males (24 GD and 15 RD) and assigned displays to type using numerical decision criteria. Although comparison of the same display types between GD and RD males revealed differences in the durations of several homologous display units (i.e., bobs or interbob pauses), only one unit differed following statistical correction for multiple comparisons. By taking into account all display variation in both populations simultaneously, however, discriminant function analysis correctly assigned display units with high accuracy to population and display type. Nevertheless, differences in unit durations often were greater between two RD populations occurring within Florida than they were between our GD and RD study populations. Thus, despite our demonstration of differences in the display temporal structure between GD and RD forms of A. carolinensis, these differences appear to be no greater in magnitude than those observed between RD populations.
A measurement is presented of the inclusive neutral current e±p scattering cross section using data collected by the H1 experiment at HERA during the years 2003 to 2007 with proton beam energies Ep ...of 920, 575, and 460 GeV. The kinematic range of the measurement covers low absolute four-momentum transfers squared, 1.5 GeV2<Q2<120 GeV2, small values of Bjorken x, 2.9⋅10−5<x<0.01, and extends to high inelasticity up to y=0.85. The structure function FL is measured by combining the new results with previously published H1 data at Ep=920 GeV and Ep=820 GeV. The new measurements are used to test several phenomenological and QCD models applicable in this low Q2 and low x kinematic domain.
The Windsor Report maintains that any member church of the Anglican Communion which unilaterally takes any action presupposing that homosexual unions are morally permissible is in contempt of the ...bonds of affection and communion in the Anglican Church. The Report offers only one reason for this claim which survives initial scrutiny: that the issue of the morality of homosexuality is not adiaphora, a matter on which orthodox Christians may reasonably disagree. But by any defensible standard, the morality of homosexuality is adiaphora. Therefore, the Anglican Communion has no grounds for complaint if a member church puts forward, for reception within its own province, a proposal for such action. Furthermore, there is a monumental difficulty with the Report's demand that member churches ought at least to consult with the wider Communion before accepting such a proposal. PUBLICATION ABSTRACT
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