31 resultados para 3-LEVEL SYSTEMS


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Bit level systolic array structures for computing sums of products are studied in detail. It is shown that these can be sub-divided into two classes and that, within each class, architectures can be described in terms of a set of constraint equations. It is further demonstrated that high performance system level functions with attractive VLSI properties can be constructed by matching data flow geometries in bit level and word level architectures.

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We address the propagation of a single photon pulse with two polarization components, i.e., a polarization qubit, in an inhomogeneously broadened "phaseonium" \Lambda-type three-level medium. We combine some of the non-trivial propagation effects characteristic for this kind of coherently prepared systems and the controlled reversible inhomogeneous broadening technique to propose several quantum information processing applications, such as a protocol for polarization qubit filtering and sieving as well as a tunable polarization beam splitter. Moreover, we show that, by imposing a spatial variation of the atomic coherence phase, an effcient quantum memory for the incident polarization qubit can be also implemented in \Lambda-type three-level systems.

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Microbeams have undergone a renaissance since their introduction and early use in the mid 60s. Recent advances in imaging, software and beam delivery have allowed rapid technological developments in microbeams for use in a range of experimental studies. The resurgence in the use of microbeams since the mid 90s has coincided with major changes in our understanding of how radiation interacts with cells. In particular, the evidence that bystander responses occur, where cells not directly irradiated can respond to irradiated neighbours, has brought about the evolution of new models of radiation response. Although these processes have been studied using a range of experimental approaches, microbeams offer a unique route by which bystander responses can be elucidated. Without exception, all of the microbeams currently active internationally have studied bystander responses in a range of cell and tissue models. Together these studies have considerably advanced our knowledge of bystander responses and the underpinning mechanisms. Much of this has come from charged particle microbeam studies, but increasingly, X-ray and electron microbeams are starting to contribute quantitative and mechanistic information on bystander effects. A recent development has been the move from studies with 2-D cell culture models to more complex 3-D systems where the possibilities of utilizing the unique characteristics of microbeams in terms of their spatial and temporal delivery will make a major impact.

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The concurrent validity of a 1 minute walk test at a child's maximum walking speed was assessed in children with bilateral spastic cerebral palsy (BSCP). The distance covered during the 1 minute walk test was compared with the children's gross motor function as assessed by the Gross Motor Function Measure (GMFM). Twenty-four male and 10 female children with CP (mean age 11y, range 4 to 16y) participated in the study. Gross Motor Function Classification System (GMFCS) levels were; level I (n=3), level II (n=17), level III (n=10), and level IV (n=4). Participants had clinical diagnoses of symmetrical diplegia (n=19), asymmetrical diplegia (n=14), and quadriplegia (n=1). Results showed a significant correlation between GMFM score and the distance covered during the 1 minute walk (r=0.92; p<0.001). There was also a significant decrease in the distance walked with increasing GMFCS level (p<0.001). We concluded that the 1 minute walk test is a valid measure for assessing functional ability in children with ambulatory BSCP. Its cost-effectiveness and user friendliness make it a potentially useful tool in the clinical setting. Further study needs to address its reliability and ability to detect change over time.

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We draw an explicit connection between the statistical properties of an entangled two-mode continuous variable (CV) resource and the amount of entanglement that can be dynamically transferred to a pair of noninteracting two-level systems. More specifically, we rigorously reformulate entanglement-transfer process by making use of covariance matrix formalism. When the resource state is Gaussian, our method makes the approach to the transfer of quantum correlations much more flexible than in previously considered schemes and allows the straightforward inclusion of the effects of noise affecting the CV system. Moreover, the proposed method reveals that the use of de-Gaussified two-mode states is almost never advantageous for transferring entanglement with respect to the full Gaussian picture, despite the entanglement in the non-Gaussian resource can be much larger than in its Gaussian counterpart. We can thus conclude that the entanglement-transfer map overthrows the

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We introduce a tool for the quantitative characterization of the departure from Markovianity of a given dynamical process. Our tool can be applied to a generic N-level system and extended straightforwardly to Gaussian continuous-variable systems. It is linked to the change of the volume of physical states that are dynamically accessible to a system and provides qualitative expectations in agreement with some of the analogous tools proposed so far. We illustrate its predictive power by tackling a few canonical examples.

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We present grizP1 light curves of 146 spectroscopically confirmed Type Ia supernovae (SNe Ia; 0.03 < z < 0.65) discovered during the first 1.5 yr of the Pan-STARRS1 Medium Deep Survey. The Pan-STARRS1 natural photometric system is determined by a combination of on-site measurements of the instrument response function and observations of spectrophotometric standard stars. We find that the systematic uncertainties in the photometric system are currently 1.2% without accounting for the uncertainty in the Hubble Space Telescope Calspec definition of the AB system. A Hubble diagram is constructed with a subset of 113 out of 146 SNe Ia that pass our light curve quality cuts. The cosmological fit to 310 SNe Ia (113 PS1 SNe Ia + 222 light curves from 197 low-z SNe Ia), using only supernovae (SNe) and assuming a constant dark energy equation of state and flatness, yields w = -1.120+0.360-0.206(Stat)+0.2690.291(Sys). When combined with BAO+CMB(Planck)+H0, the analysis yields ΩM = 0.280+0.0130.012 and w = -1.166+0.072-0.069 including all identified systematics. The value of w is inconsistent with the cosmological constant value of -1 at the 2.3σ level. Tension endures after removing either the baryon acoustic oscillation (BAO) or the H0 constraint, though it is strongest when including the H0 constraint. If we include WMAP9 cosmic microwave background (CMB) constraints instead of those from Planck, we find w = -1.124+0.083-0.065, which diminishes the discord to <2σ. We cannot conclude whether the tension with flat ΛCDM is a feature of dark energy, new physics, or a combination of chance and systematic errors. The full Pan-STARRS1 SN sample with ∼three times as many SNe should provide more conclusive results.

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We have collected initial evidence that tidal interaction between a late-type star and its close-in, massive planet can lead to a spin-up of the host star. We propose to explore this further by studying a small sample of proper motion pairs in which one of the stars is orbited a Hot Jupiter. We will determine if the gyrochronal age is different for the two stars, which would indicate a tidal spin up of the planet host star. We propose to observe 3 such systems with XMM, and to perform similar Chandra observations of 3 more systems with angular separations

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The fundamental controls on the initiation and development of gravel-dominated deposits (beaches and barriers) on paraglacial coasts are particle size and shape, sediment supply, storm wave activity (primarily runup), relative sea-level (RSL) change, and terrestrial basement structure (primarily as it affects accommodation space). This paper examines the stochastic basis for barrier organisation as shown by variation in gravel barrier architecture. We recognise punctuated self-organisation of barrier development that is disrupted by short phases of barrier instability. The latter results from positive feedback causing barrier breakdown when sediment supply is exhausted. We examine published typologies for gravel barriers and advocate a consolidated perspective using rate of RSL change and sediment supply. We also consider the temporal variation in controls on barrier development. These are examined in terms of a simple behavioural model (BARCH) for prograding gravel barrier architecture and its sensitivity to such controls. The nature of macroscale (102–103 years) gravel barrier development, including inherited characteristics that influence barrier genesis, as well as forcing from changing RSL, sediment supply, headland control and barrier inertia, is examined in the context of long-surviving barriers along the southern England coastline.

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BACKGROUND: Despite the fact that outreach and early warning systems (EWS) are an integral part of a hospital wide systems approach to improve the early identification and management of deteriorating patients on general hospital wards, the widespread implementation of these interventions in practice is not based on robust research evidence. OBJECTIVES: The primary objective was to determine the impact of critical care outreach services on hospital mortality rates. Secondary objectives included determining the effect of outreach services on intensive care unit (ICU) admission patterns, length of hospital stay and adverse events. SEARCH STRATEGY: The review authors searched the following electronic databases: EPOC Specialised Register, The Cochrane Central Register of Controlled Trials (CENTRAL) and other Cochrane databases (all on The Cochrane Library 2006, Issue 3), MEDLINE (1996-June week 3 2006), EMBASE (1974-week 26 2006), CINAHL (1982-July week 5 2006), First Search (1992-2005) and CAB Health (1990-July 2006); also reference lists of relevant articles, conference abstracts, and made contact with experts and critical care organisations for further information. SELECTION CRITERIA: Randomised controlled trials (RCTs), controlled clinical trials (CCTs), controlled before and after studies (CBAs) and interrupted time series designs (ITS) which measured hospital mortality, unanticipated ICU admissions, ICU readmissions, length of hospital stay and adverse events following implementation of outreach and EWS in a general hospital ward to identify deteriorating adult patients versus general hospital ward setting without outreach and EWS were included in the review. DATA COLLECTION AND ANALYSIS: Three review authors independently extracted data and two review authors assessed the methodological quality of the included studies. Meta-analysis was not possible due to heterogeneity. Summary statistics and descriptive summaries of primary and secondary outcomes are presented for each study. MAIN RESULTS: Two cluster-randomised control trials were included: one randomised at hospital level (23 hospitals in Australia) and one at ward level (16 wards in the UK). The primary outcome in the Australian trial (a composite score comprising incidence of unexpected cardiac arrests, unexpected deaths and unplanned ICU admissions) showed no statistical significant difference between control and medical emergency team (MET) hospitals (adjusted P value 0.640; adjusted odds ratio (OR) 0.98; 95% confidence interval (CI) 0.83 to 1.16). The UK-based trial found that outreach reduced in-hospital mortality (adjusted OR 0.52; 95% CI 0.32 to 0.85) compared with the control group. AUTHORS' CONCLUSIONS: The evidence from this review highlights the diversity and poor methodological quality of most studies investigating outreach. The results of the two included studies showed either no evidence of the effectiveness of outreach or a reduction in overall mortality in patients receiving outreach. The lack of evidence on outreach requires further multi-site RCT's to determine potential effectiveness.

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For many applications of emotion recognition, such as virtual agents, the system must select responses while the user is speaking. This requires reliable on-line recognition of the user’s affect. However most emotion recognition systems are based on turnwise processing. We present a novel approach to on-line emotion recognition from speech using Long Short-Term Memory Recurrent Neural Networks. Emotion is recognised frame-wise in a two-dimensional valence-activation continuum. In contrast to current state-of-the-art approaches, recognition is performed on low-level signal frames, similar to those used for speech recognition. No statistical functionals are applied to low-level feature contours. Framing at a higher level is therefore unnecessary and regression outputs can be produced in real-time for every low-level input frame. We also investigate the benefits of including linguistic features on the signal frame level obtained by a keyword spotter.

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Territorial politics and the statewide party, Regional Studies. The literature on political parties has been affected by a national bias. However, the multilevel nature of party organizations deserves one's attention because parties have responded as well as contributed to the rise in regional authority across most Western democracies. This paper considers statewide parties from a double perspective: as organizations subject to a range of pressures in a multilevel environment, and as actors influencing multilevel political systems. It concludes with a call for stronger links between traditional areas of party and policy research and multilevel party research and for more comparative data collection on multilevel parties and policy positions.

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A bit-level systolic array system for performing a binary tree Vector Quantization codebook search is described. This consists of a linear chain of regular VLSI building blocks and exhibits data rates suitable for a wide range of real-time applications. A technique is described which reduces the computation required at each node in the binary tree to that of a single inner product operation. This method applies to all the common distortion measures (including the Euclidean distance, the Weighted Euclidean distance and the Itakura-Saito distortion measure) and significantly reduces the hardware required to implement the tree search system. © 1990 Kluwer Academic Publishers.