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International Workshop/Symposium on Distributed simulation and Real-Time Applications (DS-RT)

作者： Bin Wang Yanlong Zhai Zishuo Wang Han Zhang Duzheng Qing Beijing Engineering Research Center of Massive Language Information Processing and Cloud Computing Applications Bijing Institute of Technology Beijing China Science and Technology on Special System Simulation Laboratory Beijing Simulation Center China

ISBN: (纸本)9781509035069

Modeling and simulation has received significant attention over the years for its ability to understand and transform real world systems. With the increasing of complexity and scale of the simulated systems, more computational power is required. Parallel discrete event simulation(PDES) is an important technology to integrate parallel computing into modeling and simulation. Time synchronization algorithm is the core of PDES, which determines the correctness and efficiency of the simulation. Traditional conservative synchronization algorithms, such as Chandy-Misra-Bryant(CMB) null message algorithm, use null message to synchronize the state and avoid deadlock among logical processes(LPs). But hybrid simulation systems contains both continuous models and discrete models, continuously changing states is typically modeled using time steps in hybrid simulation system. Therefore, hybrid systems with large disparity in time step are very common in real simulation systems. However, current conservative synchronization algorithm has not been fully investigated for this type of simulation systems and will generate massive synchronization messages. This paper proposed an enhanced null message algorithm for hybrid simulation systems with large disparity in time step. It extended the CMB algorithm by adding simulation time in null message request messages. This could significantly reduce the number of synchronization messages. Experimental results showed that our synchronization algorithm outperforms the CMB algorithm by reducing a great number of synchronization messages.

关键词： Synchronization Computational modeling Atmospheric modeling Adaptation models system recovery Ports (Computers) Complex systems

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Sub-Rayleigh limit imaging via intensity correlation measurements

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Chinese Physics B 2015年第4期24卷 211-214页

作者：姚旭日李龙珍刘雪峰俞文凯翟光杰 Key Laboratory of Electronics and Information Technology for Space System Center for Space Science and Applied ResearchChinese Academy of Sciences University of Chinese Academy of Sciences

We demonstrate sub-Rayleigh limit imaging of an object via intensity correlation measurements. The image com- pletely unaffected by the disturbance of diffraction-limit is achieved under the condition that the imaging system has an appropriate field of view. The resolution of this sub-Rayleigh limit imaging system is only tied to the lateral resolution of the illumination light.

关键词： image forming and processing speckle

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Geoacoustic characterization using vector ship noise field in a hard-bottom environment

Geoacoustic characterization using vector ship noise field i...

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OCEANS

作者： Qun-yan Ren Li Ma Shengming Guo Shengchun Piao Tianjun Liao Key Laboratory of Underwater Acoustics Environment Chinese Academy of Sciences Beijing Science and Technology on Underwater Acoustic Laboratory Harbin Engineering University Harbin State Key Laboratory of Complex System Simulation Beijing Institute of System Engineering Beijing

ISBN: (纸本)9781509015276

This paper presents our preliminary geoacoustic inversion results of the ship noise data collected by a vector sensor in 2008, Dalian, China. For the at-sea measurement, a fishing boat was served as a passive source passed by the receiver boat deploying a vector sensor, which collected the pressure field and particle velocity components at three orthogonal directions of X, Y and Z. A batch inversion scheme is adapted to optimize a Bartlett type cost function that comprises the range-dependent sound propagation features. The results from the pressure, vertical particle velocity component and the combination of them are presented, which suggests the combination processing can provide better inversion results.

关键词： Marine vehicles Oceans Geoacoustic inversion Sediments Underwater acoustics

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Feature-oriented striation processing of the noise field due to a moving ship

Feature-oriented striation processing of the noise field due...

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OCEANS

ISBN: (纸本)9781509015276

The regular striations exhibited in broadband noise spectrogram due to a moving ship have been exploited for inverse problems in underwater acoustics, e.g., sediment geoacoustic characterization and source ranging. The enhancement of the underlying interference structure for striation extraction has been a hot topic for relative applications. In this paper, a straightforward method based on the low-frequency sound propagation characteristics is proposed to strengthen the main striation features. This method intuitively enhances the striation pattern by smoothing the resultant spectrogram along range (time) for each frequency bin. The method is applied to the ship noise data collected in 2008, Dalian, and then filtered by a multi-scale line filter, which demonstrate can greatly improve the quality of extracted striations than that of raw data. A hough transformation technique is applied to reconstruct the striation segment to estimate precise geometrical information that can be used for source range estimation.

关键词： Marine vehicles Spectrogram Time-frequency analysis Sediments Distance measurement Underwater acoustics

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simulation Analysis of Linear Pulse Object Prominence for Push-Broom Spectrometer in-Orbit

Simulation Analysis of Linear Pulse Object Prominence for Pu...

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International Symposium on Optoelectronic technology and Application 2016(OTA 2016)——Conf.9 Hyperspectral Remote Sensing Applications

作者： LI Yulun MENG Xin YANG Zhen MA Xiaoshan Key Laboratory of Electronics and Information Technology for Complex Aerospace System National Space Science CenterChinese Academy of Sciences

Visual interpretation is indispensible to hyperspectral image quality evaluation. Linear pulse objects, imaged at a width of 2, 3 pixels or even smaller, are sometimes recognizable or indistinct at ot

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The view growth pattern of user generated videos on YouTube

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International Journal of u- and e- Service, science and technology 2016年第6期9卷 433-444页

作者： Zhou, Renjie Xia, Dongchen Yin, Yuyu Zhang, Jilin Zhang, Wei College of Computer Science and Technology Hangzhou Dianzi University Hangzhou China Key Laboratory Complex System Modeling and Simulation Ministry of Education Hangzhou China

With the rapid development of social media, video sharing sites like YouTube are getting more and more attention. Discovering the view growth pattern have become interesting topics for researchers as well as advertisers, media companies. In this paper, we analyze two aspects about video view growth pattern of YouTube videos. Firstly, the pattern of aggregated view is studied. It is found that the aggregated view rate peaks in the first few days, and falls quickly in the following days, and then decrease slowly during the consecutive weeks. Finally, the view rate tends to be a constant on the long run. The aggregated view count after a period of two months can be fitted with a linear line. Secondly, the view growth pattern of individual video is explored. The results indicate that the majority of videos peak at the very beginning of videos’ lifetime, and the category of view sources causes the peak is different. The view count of individual video and the view count from each source item also stabilize after a period of two months, and we finally show the referring time and active period of each source item. © 2016 SERSC.

关键词： Growth rate

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The Evaluation Method of Equipment system of systems Based on Big Data Analysis

The Evaluation Method of Equipment System of Systems Based o...

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2015 International Conference on Automation,Mechanical Control and Computational Engineering(AMCCE 2015)

作者： Liu Dong Li Kang Science and Technology on Complex Electronic System Simulation Laboratory

ISBN: (纸本)9781510803084

In the evaluation of equipment system of systems(So S), equipment data has shown some new characters, such as big volume, wide range sources, and dynamic variance. The paper pointed out the idea to evaluate equipment So S based on big data analysis techniques. The outline of the method is provided from two points of view, namely the big data processing techniques and equipment So S evaluation methods. Based on big data, equipment So S efficiency evaluation, counter evaluation, and other deeper level applications, such as intelligence processing and situation analysis, can be made. The method is a new method in the equipment So S evaluation field.

关键词： equipment system of systems efficiency evaluation data analysis

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ACCESS: A visual to near-infrared spectrum of the hot jupiter WASP-43b with evidence of H2O, but no evidence of Na or K

arXiv

引用

arXiv 2019年

作者： Weaver, Ian C. López-Morales, Mercedes Espinoza, Néstor Rackham, Benjamin V. Osip, David J. Apai, Dániel Jordán, Andrés Bixel, Alex Lewis, Nikole K. Alam, Munazza K. Kirk, James McGruder, Chima Rodler, Florian Fienco, Jennifer Center for Astrophysics Harvard & Smithsonian 60 Garden St CambridgeMA02138 United States Max-Planck-Institut für Astronomie Königstuhl 17 Heidelberg69117 Germany Department of Earth Atmospheric and Planetary Sciences Kavli Institute for Astrophysics and Space Research Massachusetts Institute of Technology CambridgeMA02139 United States Department of Astronomy/Steward Observatory University of Arizona 933 N. Cherry Avenue TucsonAZ85721 United States Earths in Other Solar Systems Team NASA Nexus for Exoplanet System Science Las Campanas Observatory Carnegie Institution of Washington Colina el Pino Casilla 601 La Serena Chile Lunar and Planetary Laboratory University of Arizona 1640 E. Univ. Blvd TucsonAZ85721 United States Facultad de Ingeniería y Ciencias Universidad Adolfo Ibáñez Av. Diagonal las Torres 2640 Peñalolén Santiago Chile Millennium Institute for Astrophysics Av. Vicuña Mackenna 4860 Macul Santiago782-0436 Chile Department of Astronomy and Carl Sagan Institute Cornell University 122 Sciences Drive 14853 IthacaNY United States European Southern Observatory Alonso de Cordova 3107 Vitacura Santiago de Chile Instituto de Astrofísica Facultad de Física Pontificia Universidad Católica de Chile Av. Vicuña Mackenna 4860 Macul Santiago7820436 Chile IAU-Gruber

We present a new ground-based visual transmission spectrum of the hot Jupiter WASP-43b, obtained as part of the ACCESS Survey. The spectrum was derived from four transits observed between 2015 and 2018, with combined wavelength coverage between 5,300 Å-9,000 Å and an average photometric precision of 708 ppm in 230 Å bins. We perform an atmospheric retrieval of our transmission spectrum combined with literature HST/WFC3 observations to search for the presence of clouds/hazes as well as Na, K, Hα, and H2O planetary absorption and stellar spot contamination over a combined spectral range of 5,318 Å-16,420 Å. We do not detect a statistically significant presence of Na I or K I alkali lines, or Hα in the atmosphere of WASP-43b. We find that the observed transmission spectrum can be best explained by a combination of heterogeneities on the photosphere of the host star and a clear planetary atmosphere with H2O. This model yields a log-evidence of 8.26 ± 0.42 higher than a flat (featureless) spectrum. In particular, the observations marginally favor the presence of large, low-contrast spots over the four ACCESS transit epochs with an average covering fraction fhet = 0.27+0−0..4216, and temperature contrast ∆T = 132 K ±132 K. Within the planet's atmosphere, we recover a log H2O volume mixing ratio of −2.78−+11..3847, which is consistent with previous H2O abundance determinations for this planet. Copyright © 2019, The Authors. All rights reserved.

关键词： Near infrared spectroscopy

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Scientific exploration platform of the space science satellite operating system 14th

Scientific exploration platform of the space science satelli...

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14th International Conference on space Operations, spaceOps 2016

作者： Meng, Bai Tai, Hu Dalin, Li National Space Science Center CAS Beijing100190 China Harbin150001 China Satellite Mission Operation Laboratory No.1 Nanertiao Zhonguancun Haidian district Beijing China Key Laboratory of Integrated Avionics and Information Technology for Complex Aerospace System No.1 Nanertiao Zhonguancun Haidian district Beijing China

ISBN: (数字)9781624104268

ISBN: (纸本)9781624104268

Detection of space science satellite is quite different from the traditional application satellite. Special scientific application of space science missions, required mission operation systems to provide more common and related services for scientific applications. At the same time, in order to be able to effectively integrate the disparate, heterogeneous scientific exploration resources, you need a distributed scientific exploration platform. It adapts for many users, with convenient ways of website, computer client, IPAD, mobile phone client and other means, unified analysis of the demand for satellite missions. The paper presents the overall architecture of SOA (Service-Oriented Architecture) based distributed platform of scientific exploration program. The system platform supports space scientific plans made for satellites, including the scientific exploration satellites and scientific experimental satellites. It can meet the need of multi-task in space scientific detection with commonality and extensibility. © 2016, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Satellites

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Global and Brazilian carbon response to El Niño Modoki 2011-2010

arXiv

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arXiv 2017年

作者： Bowman, K.W. Liu, J. Bloom, A.A. Parazoo, N.C. Lee, M. Jiang, Z. Menemenlis, D. Gierach, M.M. Collatz, G.J. Gurney, K.R. Wunch, D. Jet Propulsion Laboratory California Institute of Technology PasadenaCA United States Joint Institute for Regional Earth System Science and Engineer University of California Los AngelesCA NASA Goddard Space Flight Center GreenbeltMD United States Ecology Evolution and Environmental Science Arizona State University TempeAZ United States National Center for Atmospheric Research BoulderCO United States Department of Physics University of Toronto Toronto Canada

The El Niño Modoki in 2010 lead to historic droughts in Brazil. We quantify the global and Brazilian carbon response to this event using the NASA Carbon Monitoring system Flux (CMS-Flux) framework. Satellite observations of CO2, CO, and solar induced fluorescence (SIF) are ingested into a 4D-variational assimilation system driven by carbon cycle models to infer spatially resolved carbon fluxes including net ecosystem exchange, biomass burning, and gross primary productivity (GPP). The global net carbon flux tendency, which is the flux difference 2011-2010 and is positive for net fluxes into the atmosphere, was estimated to be -1.60 PgC between 2011-2010 while the Brazilian tendency was -0.24 ± 0.11 PgC. This estimate is broadly within the uncertainty of previous aircraft based estimates restricted to the Amazonian basin. The biomass burning tendency in Brazil was -0.24 ± 0.036 PgC, which implies a near-zero change of the net ecosystem production (NEP). The near-zero change of the NEP is the result of quantitatively comparable increase in GPP (0.34 ± 0.20) and respiration in Brazil. Comparisons of the component fluxes in Brazil to the global fluxes show a complex balance between regional contributions to individual carbon fluxes such as biomass burning, and their net contribution to the global carbon balance, e.g., the Brazilian biomass burning tendency is a significant contributor to the global biomass burning tendency but the Brazilian net flux tendency is not a dominant contributor to the global tendency. These results show the potential of multiple satellite observations to help quantify the spatially resolved response of productivity and respiration fluxes to climate variability. Copyright © 2017, The Authors. All rights reserved.

关键词： Carbon

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