618 research outputs found
A METHOD FOR EVALUATING WORK GROUP PRODUCTIVITY PRODUCTS
Numerous software products claiming to improve work group productivity are making
their way into the marketplace. How is a manager to decide whether or not to invest in
these products? This paper proposes a suitable method of formulating the evaluation
problem for work group application products. The issue of normal software evaluation
is considered first. Then group work is described and contrasted with individual work
activities. A two-level evaluation strategy consisting of broad coverage and detailed
analysis is introduced. Detailed analysis consists of functional performance,
administration, and fit applied across task, group and communications domains.
Examples, drawn from some of the products demonstrated at this Symposium, are used
to illustrate how this methodology may be applied.Information Systems Working Papers Serie
Riodinid butterfly fauna (Lepidoptera) of the Cosñipata Region, Peru: Annotated checklist, community structure, and contrast with Lycaenidae
A team of experienced lepidopterists sampled the butterfly fauna of Peruâs Cosñipata Region from 400 to 4,000 m elevation for more than a decade (7,440 field person-hours) and supplemented this samÂple with data from museum specimens and the scientific literature. An annotated checklist of Cosñipata Riodinidae (Lepidoptera: Papilionoidea) documents 398 species, which represents 29% of the world RioÂdinidae fauna. For each, it lists sample abundance, adult behavior, elevation, and temporal distribution. In the fieldwork sample, 75 species (20.9%) were sampled once and 39 (9.8%) were not encountered (collected or imaged by others). A riodinid species of median abundance was sampled an average of once every 826 field person-hours. Sampled sex ratios were 81.2% male, but were not statistically higher in species in which male perching behavior was observed. We document examples of conspicuous geographic variation in the time of male perching behavior. Species richness is greatest at low elevation and at the transition between the dry and wet seasons. There is little evidence that the community is composed of species restricted to narrow elevational bands or restricted in the adult stage to a single season. Compared with Lycaenidae, Riodinidae are significantly more restricted to lowland habitats and were sampled 2.5 times as frequently with a mean number of individuals per species more than twice as great as that of Lycaenidae
A METHOD FOR EVALUATING WORK GROUP PRODUCTIVITY PRODUCTS
Numerous software products claiming to improve work group productivity are making
their way into the marketplace. How is a manager to decide whether or not to invest in
these products? This paper proposes a suitable method of formulating the evaluation
problem for work group application products. The issue of normal software evaluation
is considered first. Then group work is described and contrasted with individual work
activities. A two-level evaluation strategy consisting of broad coverage and detailed
analysis is introduced. Detailed analysis consists of functional performance,
administration, and fit applied across task, group and communications domains.
Examples, drawn from some of the products demonstrated at this Symposium, are used
to illustrate how this methodology may be applied.Information Systems Working Papers Serie
Dynamics of a Quantum Reference Frame
We analyze a quantum mechanical gyroscope which is modeled as a large spin
and used as a reference against which to measure the angular momenta of
spin-1/2 particles. These measurements induce a back-action on the reference
which is the central focus of our study. We begin by deriving explicit
expressions for the quantum channel representing the back-action. Then, we
analyze the dynamics incurred by the reference when it is used to sequentially
measure particles drawn from a fixed ensemble. We prove that the reference
thermalizes with the measured particles and find that generically, the thermal
state is reached in time which scales linearly with the size of the reference.
This contrasts a recent conclusion of Bartlett et al. that this takes a
quadratic amount of time when the particles are completely unpolarized. We now
understand their result in terms of a simple physical principle based on
symmetries and conservation laws. Finally, we initiate the study of the
non-equilibrium dynamics of the reference. Here we find that a reference in a
coherent state will essentially remain in one when measuring polarized
particles, while rotating itself to ultimately align with the polarization of
the particles
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Session B5: Efficiency of a Nature-Like Bypass Channel at Rodley Weir, River Aire
Abstract:
Man-made physical barriers (weirs) have disrupted longitudinal connectivity in many river systems around the world for centuries. Impacts of weirs on fish communities centers on the reduced ability of fish to perform upstream migrations. To counter the potential effects these structures are having on fish communities, a number of fish pass designs have been developed to ease passage around potential barriers. To monitor the effectiveness of a recently constructed nature like bypass on the River Aire, Passive Integrated Transponder (PIT) systems were installed to observe movements of brown trout (Salmo trutta). The array consists of four swim through antennas, two at either end of the pass so that swimming direction could be determined. A total of 111 wild brown trout were caught, PIT tagged and released 380 m downstream of the fish pass entrance. In total 57 brown trout (51%) were detected on the most downstream loop, and of these 49 successfully entered the pass (86%). Thirtyeight of these successfully exited the pass in an upstream direction (78%). Further analysis found that a select number of fish used the pass as an area of refuge during high flows. The possible reasons for these findings are discussed in relation to flow, temperature, time of day, season and fish size. This information is important to improve our understanding of fish pass performance, thus informing future best practice guidance of fish passage designs
Synthetic strategies for preparing BEDT-TTF derivatives functionalised with metal ion binding groups
The syntheses of BEDT-TTF (ET) derivatives with potential metal ion binding pyridyl, bipyridyl and terpyridyl groups are achieved either by stepwise construction of the organosulfur core or via reactions of hydroxymethyl-ET for which a cheap and efficient four step route is reported. The tosylate of hydroxymethyl-ET, reported for the first time, undergoes nucleophilic substitutions with pyridyl, bipyridyl- and terpyridyl-thiolates to give new donors. The X-ray crystal structures of two substituted ET derivatives show considerable deviation of the organosulfur donor system from planarity by bending about the short molecular axis of the ET group
SDSS J115517.35+634622.0: A Newly Discovered Gravitationally Lensed Quasar
We report the discovery of SDSSJ115517.35+634622.0, a previously unknown
gravitationally lensed quasar. The lens system exhibits two images of a quasar, with an image separation of 1{\farcs}832 \pm 0.007 . Near-IR
imaging of the system reveals the presence of the lensing galaxy between the
two quasar images. Based on absorption features seen in the Sloan Digital Sky
Survey (SDSS) spectrum, we determine a lens galaxy redshift of .
The lens is rather unusual in that one of the quasar images is only
0{\farcs}22\pm0{\farcs}07 () from the center of the
lens galaxy and photometric modeling indicates that this image is significantly
brighter than predicted by a SIS model. This system was discovered in the
course of an ongoing search for strongly lensed quasars in the dataset from the
SDSS.Comment: 18 pages, 6 figures. Accepted for publication in A
Functional MRI Evaluation of Multiple Neural Networks Underlying Auditory Verbal Hallucinations in Schizophrenia Spectrum Disorders.
Functional MRI studies have identified a distributed set of brain activations to be asso ciated with auditory verbal hallucinations (AVH). However, very little is known about how activated brain regions may be linked together into AVH-generating networks. Fifteen volunteers with schizophrenia or schizoaffective disorder pressed buttons to indicate onset and offset of AVH during fMRI scanning. When a general linear model was used to compare blood oxygenation level dependence signals during periods in which subjects indicated that they were versus were not experiencing AVH ( AVH-on versus AVH-off ), it revealed AVH-related activity in bilateral inferior frontal and superior temporal regions; the right middle temporal gyrus; and the left insula, supramarginal gyrus, inferior parietal lobule, and extranuclear white matter. In an effort to identify AVH-related networks, the raw data were also processed using independent component analyses (ICAs). Four ICA components were spatially consistent with an a priori network framework based upon published meta-analyses of imaging correlates of AVH. Of these four components, only a network involving bilateral auditory cortices and posterior receptive language areas was significantly and positively correlated to the pattern of AVH-on versus AVH-off. The ICA also identified two additional networks (occipital-temporal and medial prefrontal), not fully matching the meta-analysis framework, but nevertheless containing nodes reported as active in some studies of AVH. Both networks showed significant AVH-related profiles, but both were most active during AVH-off periods. Overall, the data suggest that AVH generation requires specific and selective activation of auditory cortical and posterior language regions, perhaps coupled to a release of indirect influence by occipital and medial frontal structures
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CMIP6 skill at predicting interannual to multi-decadal summer monsoon precipitation variability
Monsoons affect the economy, agriculture, and human health of two thirds of the world's population. Therefore, predicting variations in monsoon precipitation is societally important. We explore the ability of climate models from the 6th phase of the Climate Model Intercomparison Project (CMIP6) to predict summer monsoon precipitation variability by using hindcasts from the Decadal Climate Prediction Project (Component A). The multi-model ensemble-mean shows significant skill at predicting summer monsoon precipitation from one year to 6-9 years ahead. However, this skill is dependent on the model, monsoon domain, and lead-time. In general, the skill of the multi-model ensemble-mean prediction is low in year 1 but increases for longer-lead times and is largely consistent with externally forced changes. The best captured region is northern Africa for the 2-5- and 6-9-year forecast lead times. In contrast, there is no significant skill using the ensemble-mean over East and South Asia and, furthermore, there is significant spread in skill among models for these domains. By sub-sampling the ensemble we show that the difference in skill between models is tied to the simulation of the externally forced response over East and South Asia, with models with a more skilful forced response capable of better predictions. A further contribution is from skilful prediction of Pacific Ocean temperatures for the South Asian summer monsoon at longer lead-times. Therefore, these results indicate that predictions of the East and South Asian monsoons could be significantly improved
Ecological Speciation Promoted by Divergent Regulation of Functional Genes Within African Cichlid Fishes
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