2,359 research outputs found
Managerial communication competences for knowledge hybridization and innovations: a framework for effective knowledge transfer in MNE hotel operating in Athens, Greece
Investigating the impact of business alignment on job gratification in an organization: the case of a university in Egypt
The role of leadership competencies in supporting the Al Nahda University for becoming a learning organization: a new qualitative framework of the DLOQ
Data Mining in Electronic Commerce
Modern business is rushing toward e-commerce. If the transition is done
properly, it enables better management, new services, lower transaction costs
and better customer relations. Success depends on skilled information
technologists, among whom are statisticians. This paper focuses on some of the
contributions that statisticians are making to help change the business world,
especially through the development and application of data mining methods. This
is a very large area, and the topics we cover are chosen to avoid overlap with
other papers in this special issue, as well as to respect the limitations of
our expertise. Inevitably, electronic commerce has raised and is raising fresh
research problems in a very wide range of statistical areas, and we try to
emphasize those challenges.Comment: Published at http://dx.doi.org/10.1214/088342306000000204 in the
Statistical Science (http://www.imstat.org/sts/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Moderating Effects of Dynamic Managerial Capabilities on Heterogeneous Workplaces: A Case Study of Private Banks in Egypt
Are routine investigations in acute paediatric admissions justified?
Aim: To assess the appropriateness of investigations and their impact on management of acute paediatric admissions. Method: All investigations performed within the first six hours in all consecutive paediatric admissions (n=138) over a 6 week period, in a teaching general hospital, were recorded retrospectively and the results were analysed for normality/ abnormality and effect on patient management. Results: Out of a total of 480 emergency investigations performed on 89 patients, the complete blood count, electrolytes and chest X-rays were the three investigations most likely to be deranged and influenced management in 5% (n=3), 25% (n=8) and 46% (n=6) of subjects with an abnormal result, respectively. Impact on management was more evident on analysing a subgroup admitted with mild gastroenteritis, in whom serum electrolytes were abnormal in 50% (n=19), and 42% (n=8) of these needed a change in their management. Conclusion: Rationalising the number of investigations in acute paediatric admissions would result in less discomfort to children and in a significant cost benefit.peer-reviewe
Bandwidth enhancement : correcting magnitude and phase distortion in wideband piezoelectric transducer systems
Acoustic ultrasonic measurements are widespread and commonly use transducers exhibiting
resonant behaviour due to the piezoelectric nature of their active elements, being designed
to give maximum sensitivity in the bandwidth of interest. We present a characterisation of
such transducers that provides both magnitude and phase information describing the way in
which the receiver responds to a surface displacement over its frequency range. Consequently,
these devices work efficiently and linearly over only a very narrow band of their overall
frequency range. In turn, this causes phase and magnitude distortion of linear signals. To
correct for this distortion, we introduce a software technique, which considers only the input
and the final output signals of the whole systemwhich is therefore generally applicable to any
acoustic system. By correcting for the distortion of the magnitude and phase responses, we
have ensured the signal seen at the receiver replicates the desired signal. We demonstrate a
bandwidth extension on the received signal from 60-130 kHz at -6dB to 40-200 kHz at -1dB
in a test system. The linear chirp signal we used to demonstrate this method showed the
received signal to be almost identical to the desired linear chirp. Such systemcharacterisation
will improve ultrasonic techniques when investigating material properties by maximising the
accuracy of magnitude and phase estimations
Indications of a late-time interaction in the dark sector
We show that a general late-time interaction between cold dark matter and
vacuum energy is favoured by current cosmological datasets. We characterize the
strength of the coupling by a dimensionless parameter that is free to
take different values in four redshift bins from the primordial epoch up to
today. This interacting scenario is in agreement with measurements of cosmic
microwave background temperature anisotropies from the Planck satellite,
supernovae Ia from Union 2.1 and redshift space distortions from a number of
surveys, as well as with combinations of these different datasets. We show that
a non-zero interaction is very likely at late times. We then focus on the case
in a single low-redshift bin, obtaining a nested one parameter
extension of the standard CDM model. We study the Bayesian evidence,
with respect to CDM, of this late-time interaction model, finding
moderate evidence for an interaction starting at , dependent upon the
prior range chosen for the interaction strength parameter . For this case
the null interaction (, i.e.CDM) is excluded at 99% c.l..Comment: version to appear in PRL, 6 pages, 6 figure
Differential Responses of Targeted Lung Redox Enzymes to Rat Exposure to 60 or 85% Oxygen
Rat exposure to 60% O2 (hyper-60) or 85% O2 (hyper-85) for 7 days confers susceptibility or tolerance, respectively, of the otherwise lethal effects of exposure to 100% O2. The objective of this study was to determine whether activities of the antioxidant cytosolic enzyme NAD(P)H:quinone oxidoreductase 1 (NQO1) and mitochondrial complex III are differentially altered in hyper-60 and hyper-85 lungs. Duroquinone (DQ), an NQO1 substrate, or its hydroquinone (DQH2), a complex III substrate, was infused into the arterial inflow of isolated, perfused lungs, and the venous efflux rates of DQH2 and DQ were measured. Based on inhibitor effects and kinetic modeling, capacities of NQO1-mediated DQ reduction (Vmax1) and complex III-mediated DQH2 oxidation (Vmax2) increased by ∼140 and ∼180% in hyper-85 lungs, respectively, compared with rates in lungs of rats exposed to room air (normoxic). In hyper-60 lungs, Vmax1 increased by ∼80%, with no effect on Vmax2. Additional studies revealed that mitochondrial complex I activity in hyper-60 and hyper-85 lung tissue homogenates was ∼50% lower than in normoxic lung homogenates, whereas mitochondrial complex IV activity was ∼90% higher in only hyper-85 lung tissue homogenates. Thus NQO1 activity increased in both hyper-60 and hyper-85 lungs, whereas complex III activity increased in hyper-85 lungs only. This increase, along with the increase in complex IV activity, may counter the effects the depression in complex I activity might have on tissue mitochondrial function and/or reactive oxygen species production and may be important to the tolerance of 100% O2 observed in hyper-85 rats
Modeling and applications of the focus cue in conventional digital cameras
El enfoque en cámaras digitales juega un papel fundamental tanto en la calidad de la imagen como en la percepción del entorno. Esta tesis estudia el enfoque en cámaras digitales convencionales, tales como cámaras de móviles, fotográficas, webcams y similares. Una revisión rigurosa de los conceptos teóricos detras del enfoque en cámaras convencionales muestra que, a pasar de su utilidad, el modelo clásico del thin lens presenta muchas limitaciones para aplicación en diferentes problemas relacionados con el foco. En esta tesis, el focus profile es propuesto como una alternativa a conceptos clásicos como la profundidad de campo. Los nuevos conceptos introducidos en esta tesis son aplicados a diferentes problemas relacionados con el foco, tales como la adquisición eficiente de imágenes, estimación de profundidad, integración de elementos perceptuales y fusión de imágenes. Los resultados experimentales muestran la aplicación exitosa de los modelos propuestos.The focus of digital cameras plays a fundamental role in both the quality of the acquired images and the perception of the imaged scene. This thesis studies the focus cue in conventional cameras with focus control, such as cellphone cameras, photography cameras, webcams and the like. A deep review of the theoretical concepts behind focus in conventional cameras reveals that, despite its usefulness, the widely known thin lens model has several limitations for solving different focus-related problems in computer vision. In order to overcome these limitations, the focus profile model is introduced as an alternative to classic concepts, such as the near and far limits of the depth-of-field. The new concepts introduced in this dissertation are exploited for solving diverse focus-related problems, such as efficient image capture, depth estimation, visual cue integration and image fusion. The results obtained through an exhaustive experimental validation demonstrate the applicability of the proposed models
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