14,736 research outputs found
Limited sensitivity analysis of ARAIM availability for LPV-200 over Australia using real data
Current availability of Advanced Receiver Autonomous Integrity Monitoring (ARAIM) for LPV-200 in aviation is experimentally investigated using real navigation data and GPS measurements collected at 60 stations across Australia. ARAIM algorithm and fault probabilities were first discussed. Availability sensitivity analysis due to changes in the elevation mask angle and the error model parameters URA, URE, and nominal biases for integrity and accuracy used for computation of the protection level is presented. It is shown that incorporation of other GNSS constellation with GPS in ARAIM is needed to achieve LPV-200 Australia wide. The inclusion of BeiDou with GPS at two tests sites in Western and Eastern Australia demonstrates the promising potential of achieving this goal
Refraction of dispersive shock waves
We study a dispersive counterpart of the classical gas dynamics problem of
the interaction of a shock wave with a counter-propagating simple rarefaction
wave often referred to as the shock wave refraction. The refraction of a
one-dimensional dispersive shock wave (DSW) due to its head-on collision with
the centred rarefaction wave (RW) is considered in the framework of defocusing
nonlinear Schr\"odinger (NLS) equation. For the integrable cubic nonlinearity
case we present a full asymptotic description of the DSW refraction by
constructing appropriate exact solutions of the Whitham modulation equations in
Riemann invariants. For the NLS equation with saturable nonlinearity, whose
modulation system does not possess Riemann invariants, we take advantage of the
recently developed method for the DSW description in non-integrable dispersive
systems to obtain main physical parameters of the DSW refraction. The key
features of the DSW-RW interaction predicted by our modulation theory analysis
are confirmed by direct numerical solutions of the full dispersive problem.Comment: 45 pages, 23 figures, minor revisio
Higher-order squeezing for the codirectional Kerr nonlinear coupler
In this Letter we study the evolution of the higher-order squeezing, namely,
th-order single-mode squeezing, sum- and difference-squeezing for the
codirectional Kerr nonlinear coupler. We show that the amount of squeezing
decreases when , i.e. the squeezing order, increases. For specific values of
the interaction parameters squeezing factors exhibit a series of
revival-collapse phenomena, which become more pronounced when the value of
increases. Sum-squeezing can provide amounts of squeezing greater than those
produced by the th higher-order () squeezing for the same values of
interaction parameters and can map onto amplitude-squared squeezing. Further,
we prove that the difference-squeezing is not relevant measure for obtaining
information about squeezing from this device.Comment: 13 pages, 3 figure
Bis(5-methyl-1-phenyl-1H-1,2,3-triazole-4-carboxylic acid) monohydrate
The crystal structure of the title compound, 2C10H9N3O2·H2O, synthesized from azidobenzene and ethyl acetylacetate, is stabilized by O—H⋯O and O—H⋯N hydrogen bonds
Photonic Localization of Interface Modes at the Boundary between Metal and Fibonacci Quasi-Periodic Structure
We investigated on the interface modes in a heterostructure consisting of a
semi-infinite metallic layer and a semi-infinite Fibonacci quasi-periodic
structure. Various properties of the interface modes, such as their spatial
localizations, self-similarities, and multifractal properties are studied. The
interface modes decay exponentially in different ways and the modes in the
lower stable gap possess highest spatial localization. A localization index is
introduced to understand the localization properties of the interface modes. We
found that the localization index of the interface modes in the upper stable
gap will converge to two slightly different constants according to the parity
of the Fibonacci generation. In addition, the localization-delocalization
transition is also found in the interface modes of the transient gap.Comment: 20 pages, 5figure
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An Open-Label, Multicenter, Phase I, Dose Escalation Study with Phase II Expansion Cohort to Determine the Safety, Pharmacokinetics, and Preliminary Antitumor Activity of Intravenous TKM-080301 in Subjects with Advanced Hepatocellular Carcinoma.
Lessons learnedTKM-080301 showed a favorable toxicity profile at the studied dose.TKM-080301 targeting PLK1 through small interfering RNA mechanism did not demonstrate improved overall survival in patients with advanced hepatocellular carcinoma compared with historical control. Preliminary antitumor activity as shown in this early-phase study does not support further evaluation as a single agent.BackgroundPolo-like kinase 1 (PLK1) is overexpressed in hepatocellular carcinoma (HCC). Knockdown of PLK1 expression by PLK1 small interfering RNA (siRNA) in an HCC cell line showed reduced expression in RNA-induced silencing complex and a reduction in cell proliferation.MethodsA 3 + 3 dose escalation plus expansion cohort at the maximum tolerated dose (MTD) was implemented. Patients with HCC, Eastern Cooperative Oncology Group (ECOG) performance status ≤2, and Child-Pugh score A received TKM-080301 as an intravenous infusion once every week for 3 consecutive weeks, repeated every 28 days.ResultsThe study enrolled 43 patients. The starting dose of TKM-080301 was 0.3 mg/kg, and MTD was declared at 0.75 mg/kg. Following the development of grade 4 thrombocytopenia in two subjects on the expansion cohort, the MTD was redefined at 0.6 mg/kg. Four patients did not have any evaluable postbaseline scan. Of the other 39 subjects who had received at least 0.3 mg/kg, 18 subjects (46.2%) had stable disease (SD) by independent RECIST 1.1 criteria. By Choi criteria, eight subjects (23.1%) had a partial response (PR). For 37 assessable subjects, with 2 subjects censored, median progression-free survival (PFS) was 2.04 months. Median survival for the whole study population was 7.5 months.ConclusionTKM-080301 was generally well tolerated. In this early-phase study, antitumor effect for TKM 080301 was limited. Further evaluation as a single agent in large randomized trials is not warranted
A new WPAN Model for NS-3 simulator
International audienceWireless sensor networks are one of the most challenging topics in research world due to the nature of the wireless communication and the constraints related to the sensor’s components. However, this field knows a very fast progress and new technologies are involved. One of the hottest trends of the future WSN is the I/WoT ‘Internet/Web of Things’. For the wireless medium access and radio transmission (MAC and PHY), I/WoT has chosen the IEEE 802.15.4 standard. Some researchers have proposed simulation models to analyze this standard in different simulation environment. In this paper we propose a new WPAN model for the NS-3 simulator. This model implements most of the IEEE 802.15.4 standard feature and modes of operations. Furthermore, a 6LoWPAN Model is used to incorporate the IEEE 802.15.4 into the IPv6 architecture by interfacing the IPv6 model of NS-3 with our new IEEE 802.15.4 standard model. Thus, we believe that this WPAN work can be seen as a foundation for future I/WoT simulation on NS-3
Maintaining real-time precise point positioning during outages of orbit and clock corrections
The precise point positioning (PPP) is a popular positioning technique that is dependent on the use of precise orbits and clock corrections. One serious problem for real-time PPP applications such as natural hazard early warning systems and hydrographic surveying is when a sudden communication break takes place resulting in a discontinuity in receiving these orbit and clock corrections for a period that may extend from a few minutes to hours. A method is presented to maintain real-time PPP with 3D accuracy less than a decimeter when such a break takes place. We focus on the open-access International GNSS Service (IGS) real-time service (RTS) products and propose predicting the precise orbit and clock corrections as time series. For a short corrections outage of a few minutes, we predict the IGS-RTS orbits using a high-order polynomial, and for longer outages up to 3 h, the most recent IGS ultra-rapid orbits are used. The IGS-RTS clock corrections are predicted using a second-order polynomial and sinusoidal terms. The model parameters are estimated sequentially using a sliding time window such that they are available when needed. The prediction model of the clock correction is built based on the analysis of their properties, including their temporal behavior and stability. Evaluation of the proposed method in static and kinematic testing shows that positioning precision of less than 10 cm can be maintained for up to 2 h after the break. When PPP re-initialization is needed during the break, the solution convergence time increases; however, positioning precision remains less than a decimeter after convergence
Examining Dense Data Usage near the Regions with Severe Storms in All-Sky Microwave Radiance Data Assimilation and Impacts on GEOS Hurricane Analyses
Many numerical weather prediction (NWP) centers assimilate radiances affected by clouds and precipitation from microwave sensors, with the expectation that these data can provide critical constraints on meteorological parameters in dynamically sensitive regions to make significant impacts on forecast accuracy for precipitation. The Global Modeling and Assimilation Office (GMAO) at NASA Goddard Space Flight Center assimilates all-sky microwave radiance data from various microwave sensors such as all-sky GPM Microwave Imager (GMI) radiance in the Goddard Earth Observing System (GEOS) atmospheric data assimilation system (ADAS), which includes the GEOS atmospheric model, the Gridpoint Statistical Interpolation (GSI) atmospheric analysis system, and the Goddard Aerosol Assimilation System (GAAS). So far, most of NWP centers apply same large data thinning distances, that are used in clear-sky radiance data to avoid correlated observation errors, to all-sky microwave radiance data. For example, NASA GMAO is applying 145 km thinning distances for most of satellite radiance data including microwave radiance data in which all-sky approach is implemented. Even with these coarse observation data usage in all-sky assimilation approach, noticeable positive impacts from all-sky microwave data on hurricane track forecasts were identified in GEOS-5 system. The motivation of this study is based on the dynamic thinning distance method developed in our all-sky framework to use of denser data in cloudy and precipitating regions due to relatively small spatial correlations of observation errors. To investigate the benefits of all-sky microwave radiance on hurricane forecasts, several hurricane cases selected between 2016-2017 are examined. The dynamic thinning distance method is utilized in our all-sky approach to understand the sources and mechanisms to explain the benefits of all-sky microwave radiance data from various microwave radiance sensors like Advanced Microwave Sounder Unit (AMSU-A), Microwave Humidity Sounder (MHS), and GMI on GEOS-5 analyses and forecasts of various hurricanes
Информационные технологии в банковской системе
Almost all activities of the Bank subject to the domination systems. The system itself involves a procedure control, a set of interconnected elements, procedures, methods, and many similar concepts. When the Bank is recruiting employees, it applies to this particular system, which involves placing ads on job interviews, the definition of appropriate skills, discussion of working conditions and so on. This process is a slender organized system with its internal procedures and prescribed norms
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