Multi-Sensor Retrieval of Aerosol Optical Properties for Near-Real-Time Applications Using the Metop Series of Satellites: Concept, Detailed Description, and First Validation

The Polar Multi-Sensor Aerosol product (PMAp) is based on the synergistic use of three instruments from the Metop platform, GOME-2, AVHRR, and IASI. The retrieval algorithm includes three major steps: a pre-identification of the aerosol class, a selection of the aerosol model, and a calculation of the Aerosol Optical Depth (AOD). This paper provides a detailed description of the PMAp retrieval, which combines information provided by the three instruments. The retrieved AOD is qualitatively evaluated, and a good temporal as well as spatial performance is observed, including for the transition between ocean and land. More quantitatively, the performance is evaluated by comparison to AERONET in situ measurements. Very good consistency is also observed when compared to other space-based data such as MODIS or VIIRS. The paper demonstrates the ability of this first generation of synergistic products to derive reliable AOD, opening the door for the development of synergistic products from the instruments to be embarked on the coming Metop Second Generation platform. PMAp has been operationally distributed in near-real-time since 2014 over ocean, and 2016 over land.

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In Situ and Real Time Investigation of Directional Solidification of Al - Ni Alloys by Synchrotron Imaging

Materials Science Forum ◽

10.4028/www.scientific.net/msf.508.75 ◽

2006 ◽

Vol 508 ◽

pp. 75-80 ◽

Cited By ~ 1

Author(s):

Guillaume Reinhart ◽

Henri Nguyen-Thi ◽

J. Gastaldi ◽

Bernard Billia ◽

Nathalie Mangelinck-Noël ◽

...

Keyword(s):

Real Time ◽

Imaging Techniques ◽

Ni Alloys ◽

X Ray Imaging ◽

Major Interest ◽

Synchrotron Imaging ◽

Time Observation ◽

Real Time Observation ◽

Selection Of

Solidification is a dynamic phenomena and, as a consequence, it is of major interest to be able to investigate this process by in situ and real time observation. With synchrotron sources, this can be achieved by applying X-ray Imaging techniques (Radiography and Topography). Hence it is possible to follow the dynamical selection of solidification pattern on metallic alloys and to observe strain effects during growth process. In this paper, we present results obtained by using separately the two imaging techniques for the study of the microstructure formation during Al – Ni alloys solidification.

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An In-Flight Calibration Method for Near-Real-Time Humidity Measurements with the Airborne MOZAIC Sensor

Journal of Atmospheric and Oceanic Technology ◽

10.1175/2007jtecha975.1 ◽

2008 ◽

Vol 25 (5) ◽

pp. 656-666 ◽

Cited By ~ 13

Author(s):

Herman G. J. Smit ◽

Andreas Volz-Thomas ◽

Manfred Helten ◽

Werner Paetz ◽

Dieter Kley

Keyword(s):

Real Time ◽

Lower Stratosphere ◽

Potential Temperature ◽

Calibration Method ◽

Measured Temperature ◽

Humidity Measurements ◽

The Tropics ◽

Selection Of ◽

Good Agreement

Abstract A new in-flight calibration (IFC) method is described for the humidity sensor flown routinely since 1994 on the Measurement of Ozone and Water Vapor by Airbus In-Service Aircraft (MOZAIC) program’s aircraft. The IFC method corrects the potential drift of the sensor offset at zero relative humidity, which is the critical parameter in determining the uncertainty of the measurements. The sensor offset is determined from the measurements themselves as obtained during periods when the aircraft is flying in the lower stratosphere at or above the hygropause, where the H2O mixing ratio reaches well-defined minimum values of about 5 ppmv and the contribution of atmospheric H2O to the sensor signal is minimal. The selection of stratospheric data is achieved with the help of potential temperature, which can be calculated in situ from measured temperature and pressure. The IFC method is capable of providing humidity measurements in near–real time with an uncertainty of ±8% RH at the surface and ±7% RH in the upper troposphere. For validation, the IFC method was applied to 5 yr of archived raw signals from the MOZAIC aircraft. The resulting humidity data are in good agreement (within 2% RH) with the original MOZAIC data that used monthly pre- and postflight calibrations of the sensor. The standard deviation of the differences varies with altitude between ±4% and ±6% RH, which is comparable to the accuracy of the MOZAIC laboratory calibrations. Compared to MOZAIC operation based on monthly calibrations in the laboratory, the use of IFC will substantially reduce the efforts for maintenance and thus will enable operation of the sensor on a large fleet of in-service aircraft for near-real-time measurements of humidity in the troposphere. Because the IFC method will not work on aircraft that never enter the lower stratosphere, for example, aircraft that fly exclusively regional routes or in the tropics, regular offline calibrations will remain important for such aircraft.

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On the Selection of Architectures for Distributed Computer Systems in Real-Time Applications

IEEE Transactions on Nuclear Science ◽

10.1109/tns.1977.4328723 ◽

1977 ◽

Vol 24 (1) ◽

pp. 454-459 ◽

Cited By ~ 3

Author(s):

J. V. R. L'Archeveque ◽

G. Yan

Keyword(s):

Real Time ◽

Computer Systems ◽

Real Time Applications ◽

Distributed Computer Systems ◽

Selection Of

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Development of first generation in-situ pathogen detection system (Gen1-IPDS) based on NanoGene assay for near real time E. coli O157:H7 detection

Biosensors and Bioelectronics ◽

10.1016/j.bios.2013.10.056 ◽

2014 ◽

Vol 54 ◽

pp. 229-236 ◽

Cited By ~ 19

Author(s):

Kristi A. Mitchell ◽

Beelee Chua ◽

Ahjeong Son

Keyword(s):

Real Time ◽

Pathogen Detection ◽

First Generation ◽

Detection System ◽

E Coli

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Experimental Evaluation and Selection of Data Consistency Mechanisms for Hard Real-Time Applications on Multicore Platforms

IEEE Transactions on Industrial Informatics ◽

10.1109/tii.2013.2290585 ◽

2014 ◽

Vol 10 (2) ◽

pp. 903-918 ◽

Cited By ~ 12

Author(s):

Gang Han ◽

Haibo Zeng ◽

Marco Di Natale ◽

Xue Liu ◽

Wenhua Dou

Keyword(s):

Real Time ◽

Experimental Evaluation ◽

Data Consistency ◽

Multicore Platforms ◽

Real Time Applications ◽

Hard Real Time ◽

Selection Of

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Maintaining Consistency Over A Network in Real-Time Applications

10.23919/acc.1989.4790248 ◽

1989 ◽

Author(s):

Insup Lee ◽

Susan Davidson ◽

Victor Wolfe

Keyword(s):

Real Time ◽

Real Time Applications

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Probing the Dynamic Self-Assembly Behaviour of Photoswitchable Wormlike Micelles in Real Time

10.26434/chemrxiv.7098695 ◽

2018 ◽

Author(s):

Elaine A. Kelly ◽

Judith E. Houston ◽

Rachel Evans

Keyword(s):

Real Time ◽

Absorption Spectroscopy ◽

Self Assembly ◽

Uv Light ◽

Wormlike Micelles ◽

Tetraethylene Glycol ◽

Light Illumination ◽

First Time ◽

Dependent Processes

Understanding the dynamic self-assembly behaviour of azobenzene photosurfactants (AzoPS) is crucial to advance their use in controlled release applications such asdrug delivery and micellar catalysis. Currently, their behaviour in the equilibrium cis-and trans-photostationary states is more widely understood than during the photoisomerisation process itself. Here, we investigate the time-dependent self-assembly of the different photoisomers of a model neutral AzoPS, <a>tetraethylene glycol mono(4′,4-octyloxy,octyl-azobenzene) </a>(C8AzoOC8E4) using small-angle neutron scattering (SANS). We show that the incorporation of in-situUV-Vis absorption spectroscopy with SANS allows the scattering profile, and hence micelle shape, to be correlated with the extent of photoisomerisation in real-time. It was observed that C8AzoOC8E4could switch between wormlike micelles (transnative state) and fractal aggregates (under UV light), with changes in the self-assembled structure arising concurrently with changes in the absorption spectrum. Wormlike micelles could be recovered within 60 seconds of blue light illumination. To the best of our knowledge, this is the first time the degree of AzoPS photoisomerisation has been tracked in-situthrough combined UV-Vis absorption spectroscopy-SANS measurements. This technique could be widely used to gain mechanistic and kinetic insights into light-dependent processes that are reliant on self-assembly.

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Wave Forecasts in Muddy Coastal Environments: Model Development and Real-Time Applications

10.21236/ada630113 ◽

2004 ◽

Author(s):

Alexandru Sheremet ◽

Gregory W. Stone ◽

James M. Kaihatu

Keyword(s):

Real Time ◽

Model Development ◽

Coastal Environments ◽

Real Time Applications

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Network Selection in Wireless Heterogeneous Environment Based on Available Bandwidth Estimation

Recent Patents on Computer Science ◽

10.2174/2213275912666191018112959 ◽

2019 ◽

Vol 12 ◽

Author(s):

Kiran Ahuja ◽

Brahmjit Singh ◽

Rajesh Khanna

Keyword(s):

Real Time ◽

Estimation Error ◽

Network Selection ◽

Bandwidth Estimation ◽

Heterogeneous Environment ◽

Bootstrap Approximation ◽

Available Bandwidth ◽

Internet Connection ◽

Available Bandwidth Estimation ◽

Selection Of

Background: With the availability of multiple options in wireless network simultaneously, Always Best Connected (ABC) requires dynamic selection of the best network and access technologies. Objective: In this paper, a novel dynamic access network selection algorithm based on the real time is proposed. The available bandwidth (ABW) of each network is required to be estimated to solve the network selection problem. Method: Proposed algorithm estimates available bandwidth by taking averages, peaks, low points and bootstrap approximation for network selection. It monitors real-time internet connection and resolves the selection issue in internet connection. The proposed algorithm is capable of adapting to prevailing network conditions in heterogeneous environment of 2G, 3G and WLAN networks without user intervention. It is implemented in temporal and spatial domains to check its robustness. Estimation error, overhead, estimation time with the varying size of traffic and reliability are used as the performance metrics. Results: Through numerical results, it is shown that the proposed algorithm’s ABW estimation based on bootstrap approximation gives improved performance in terms of estimation error (less than 20%), overhead (varies from 0.03% to 83%) and reliability (approx. 99%) with respect to existing techniques. Conclusion: Our proposed methodology of network selection criterion estimates the available bandwidth by taking averages, peaks, and low points and bootstrap approximation method (standard deviation) for the selection of network in the wireless heterogeneous environment. It monitors real-time internet connection and resolves internet connections selection issue. All the real-time usage and test results demonstrate the productivity and adequacy of available bandwidth estimation with bootstrap approximation as a practical solution for consistent correspondence among heterogeneous wireless networks by precise network selection for multimedia services.

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