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improving multi-model Ensemble Forecasts of Tropical Cyclone intensity Using Bayesian model Averaging

Journal of meteorological Research 2018年第5期32卷 794-803页

作者： Xiaojiang SONG Yuejian ZHU Jiayi PENG Hong GUAN Key Laboratory of Research on marine Hazards Forecasting National Marine Environmental Forecasting Center Environmental modeling Center NOAA/NWS/NCEP i.m.systems group Inc. and NOAA/NWS/NCEP/EMC System Research group Inc. Colorado Springs CO 80901 and NOAA/NWS/NCEP/EMC

This paper proposes a method for multi-model ensemble forecasting based on Bayesian model averaging （BmA）, aiming to improve the accuracy of tropical cyclone （TC） intensity forecasts, especially forecasts of minimum surface pressure at the cyclone center （Pmin）＇ The multi-model ensemble comprises three operational forecast models： the Global Forecast System （GFS） of ncep, the Hurricane Weather Research and Forecasting （HWRF） models of ncep, and the integrated Forecasting System （iFS） of ECmWF. The mean of a predictive distribution is taken as the BmA forecast. in this investigation, bias correction of the minimum surface pressure was applied at each forecast lead time, and the distribution （or probability density function, PDF） of emin was used and transformed. Based on summer season forecasts for three years, we found that the intensity errors in TC forecast from the three models var-ied significantly. The HWRF had a much smaller intensity error for short lead-time forecasts. To demonstrate the proposed methodology, cross validation was implemented to ensure more efficient use of the sample data and more reliable testing. Comparative analysis shows that BmA for this three-model ensemble, after bias correction and distri-bution transformation, provided more accurate forecasts than did the best of the ensemble members （HWRF）, with a 5%-7% decrease in root-mean-square error on average. BmA also outperformed the multi-model ensemble, and it produced ＂predictive variance＂ that represented the forecast uncertainty of the member models. in a word, the BmA method used in the multi-model ensemble forecasting was successful in TC intensity forecasts, and it has the poten-tial to be applied to routine operational forecasting.

关键词： tropical cyclone Bayesian model average intensity bias correction forecast uncertainty ensemble forecast

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20 TO 30-DAY AND 30 TO 60-DAY OSCiLLATiONS iN ASSimiLATED GLOBAL DATASETS USiNG TRmm RAiNFALL OBSERVATiONS

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Journal of Tropical meteorology 2010年第3期16卷 210-220页

作者：陶丽杨松陆维松 Key Laboratory of meteorological Disaster of ministry of Education i.m.systems group at noaa/NESDiS Camp Springs

The influences of Tropical Rainfall measuring mission （TRmm） precipitation products on the structure and underlying physics of intraseasonal oscillation （iSO） are investigated with the U.S. National Aeronautics and Space Administration Goddard Earth Observing System model version 3 （GEOS-3） data assimilation system （DAS）. The strong iSO phase in the 1998 summer is apparently located in the Asian monsoon region and the east equatorial Pacific region. The eastward propagation is a dominant feature for the tropical iSO at 20 to 30-day oscillation while the northeastward propagation is the salient iSO at 30 to 60-day oscillation over the 10~N to 25~N belt region. it appears that the Kelvin wave structure is for the tropical 20 to 30-day oscillation. The tropical 30 to 60-day oscillation has the characteristics of the Kelvin-Rossby wave. The impact of satellite-derived precipitation （and its associated latent heating） on the iSO intensity is limited in the GEOS-3 assimilation system. However, its impact on the iSO spatial structures is obvious. Overall, the results demonstrate a better eastward propagation and a northward propagation of iSO with the TRmm precipitation simulation, indicating that latent heating is very important in exciting the equatorial iSO. Key words： 20 to 30-day oscillation; 30 to 60-day oscillation; GEOS data assimilation system; Kelvin wave; TRmm precipitation

关键词： infrared remote sensing retrieval atmospheric sounding profile mODiS AiRS

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Experimental investigation of spectral evolution in flash radiation by hypervelocity impact on aluminum plates

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Defence Technology（防务技术） 2024年第7期37卷 96-110页

作者： Xing Chen Yonggang Lu Zhiwen Li Zhonghua Cui institute of systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina Chongqing Qianwei Technology group Co. LtdChongqing 401121China

in this study,a series of hypervelocity impact tests were carried out based on a two-stage light gas gun,and the sequence spectrum and radiation evolution data of the impact products under different impact conditions were *** diameter of the projectile is 3-5 mm,the impact velocity is 3.13-6.58 km/s,and the chamber pressure is 0.56-990 *** spectrum of ejected debris cloud in the 250-310 nm band were obtained using a transient spectral measurement system and a multi-channel radiometer measurement *** test results reveal that the flash radiation intensity increases as a power function with the kinetic energy of the ***,the peak value of the line spectrum decreases as the chamber vacuum degree increases,while the radiation width gradually *** line spectrum in the spectral characterization curve corresponds to the ejected debris clouds splitting phase,which does not produce significant line spectrum during material fragmentation and is dominated by the continuum spectrum produced by blackbody *** will appear one or three characteristic peaks in the flash radiation time curve,the first and second peaks correspond to the penetration phase and the third peak corresponds to the expansion phase of the ejected debris clouds on the time scale,the first and second peaks are more sensitive to the chamber vacuum degree,and when the pressure is higher than 99 Pa,the first and second characteristic peaks will *** radiant heat attenuation of the flash under different impact conditions is significantly different,the attenuation exponent has a power function relationship with the impact velocity and the chamber vacuum degree,while the attenuation exponent has a linear relationship with the diameter of the projectile,the specific expression of the attenuation exponent is obtained by *** findings from this research can serve as a valuable reference for remote diagnostic technologies based on flash radiation characte

关键词： Hypervelocity impact Flash radiation Evolution Spectral characteristics Damage evaluation

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Satellite Data Assimilation of Upper-Level Sounding Channels in HWRF with Two Different model Tops

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Journal of meteorological Research 2015年第1期29卷 1-27页

作者：邹晓蕾翁富忠 Vijay TALLAPRAGADA 林琳张邦林吴陈锋秦正坤 Earth System Science interdisciplinary Center University of Maryland noaa Center for Satellite Applications and Research College Park noaa ncep Environmental modeling Center College Park i.m.systems group Inc.Rockville Xiamen meteorological Bureau Nanjing University of information Science & Technology

The Advanced microwave Sounding Unit-A（AmSU-A） onboard the noaa satellites noaa-18 and noaa-19 and the European Organization for the Exploitation of meteorological Satellites（EUmETSAT）met Op-A, the hyperspectral Atmospheric infrared Sounder（AiRS） onboard Aqua, the High resolution infra Red Sounder（HiRS） onboard noaa-19 and met Op-A, and the Advanced Technology microwave Sounder（ATmS） onboard Suomi National Polar-orbiting Partnership（NPP） satellite provide upper-level sounding channels in tropical cyclone environments. Assimilation of these upper-level sounding channels data in the Hurricane Weather Research and Forecasting（HWRF） system with two different model tops is investigated for the tropical storms Debby and Beryl and hurricanes Sandy and isaac that occurred in 2012. it is shown that the HWRF system with a higher model top allows more upper-level microwave and infrared sounding channels data to be assimilated into HWRF due to a more accurate upper-level background profile. The track and intensity forecasts produced by the HWRF data assimilation and forecast system with a higher model top are more accurate than those with a lower model top.

关键词： model top data assimilation satellite hurricane

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A framework of force of information influence and application for C4KiSR system

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Journal of systems Engineering and Electronics 2024年第2期35卷 430-443页

作者： mAO Shaojie DiAO Lianwang SUN Yu WANG Heng Yi Kan XU Xin mAO Xiaobin ZHANG Kecheng SHENG Long Science and Technology on information systems Engineering Laboratory The 28th Research Institute of China Electronics Technology Group CorporationNanjing 210007China Unit 94860 of the PLA Nanjing 210008China

The subversive nature of information war lies not only in the information itself, but also in the circulation and application of information. it has always been a challenge to quantitatively analyze the function and effect of information flow through command, control, communications, computer, kill, intelligence,surveillance, reconnaissance (C4KiSR) system. in this work, we propose a framework of force of information influence and the methods for calculating the force of information influence between C4KiSR nodes of sensing, intelligence processing,decision making and fire attack. Specifically, the basic concept of force of information influence between nodes in C4KiSR system is formally proposed and its mathematical definition is provided. Then, based on the information entropy theory, the model of force of information influence between C4KiSR system nodes is constructed. Finally, the simulation experiments have been performed under an air defense and attack scenario. The experimental results show that, with the proposed force of information influence framework, we can effectively evaluate the contribution of information circulation through different C4KiSR system nodes to the corresponding tasks. Our framework of force of information influence can also serve as an effective tool for the design and dynamic reconfiguration of C4KiSR system architecture.

关键词： information warfare command control communications computer kill intelligence surveillance reconnaissance(C4KiSR)system information circulation force of information influence information entropy

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TROPiCAL CYCLONE AmOS (2016) FORECASTiNG CHALLENGES: A mODEL'S PERSPECTiVE

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Tropical Cyclone Research and Review 2018年第3期7卷 172-178页

作者： TRACEY DORiAN BiLL WARD Yi-LENG CHEN i.m.systems group at noaa/ncep/emc College Park NWS Pacific Region Headquarters University of Hawai'i at mānoa

The tropical cyclone(TC)named Amos(2016)that impacted the Samoan islands on 23 April 2016 was a particularly dif f icult storm to *** the intensity changes and the track of Amos represent a signif icant challenge for forecasters and this is briefl y summarized in this *** forecasts initially indicated that the cyclone would track south of the Samoan ***,the forecasts generally changed to a direct hit over Samoa as a Category 4 storm at approximately 0000 U TC 24April based on model cycles initialized at 0000 UTC 23 *** Amos’central pressure dropped from 983 hPa to 957 hPa between 0000 UTC 21 April and 0000 UTC *** models did not pick up on this rapid intensif ication until the intensif ication had already begun around0000 UTC 21 *** models also struggled to capture the rapid weakening of TC Amos due to vertical wind shear that began 0000 UTC 24 April as the cyclone continued to move north of the *** of the initially ominous track forecasts for TC Amos to hit land,preparations for a Category 3 or Category 4 cyclone were underway in the Samoan islands and the population prepared for the *** the center of the storm moved north of the islands as a weaker storm than anticipated,the residents of the Samoan islands were both surprised and relieved that the cyclone only gave a"glancing blow"to the islands and that the impacts were not as bad as originally *** in-depth evaluation of this particular tropical cyclone helps to shed some light on model def iciencies and can be used to help determine future model changes.

关键词： evaluation of TC forecasts TC Amos Samoan islands

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Enhanced quantum resources via two distant atom-cavity systems under the influence of atomic dissipation

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Communications in Theoretical Physics 2024年第2期76卷 62-73页

作者： m Setodeh Kheirabady m K Tavassoly m Rafeie E Ghasemian Laser and Optics group Faculty of PhysicsYazd UniversityYazd 89195-741Iran Department of Electrical Engineering Faculty of Intelligent Systems Engineering and Data SciencePersian Gulf UniversityBushehrIran

Quantum resources such as entanglement and coherence are the holy grail for modern quantum technologies. Although the unwanted environmental effects tackle quantum information processing tasks, suprisingly these key quantum resources may be protected and even enhanced by the implementation of some special hybrid open quantum systems. Here, we aim to show how a dissipative atom-cavity-system can be accomplished to generate enhanced quantum *** do so, we consider a couple of dissipative cavities, where each one contains two effective two-level atoms interacting with a single-mode cavity field. in practical applications, a classical laser field may be applied to drive each atomic subsystem. After driving the system, a Bell-state measurement is performed on the output of the system to quantify the entanglement and coherence. The obtained results reveal that the remote entanglement and coherence between the atoms existing inside the two distant cavities are not only enhanced, but can be stabilized, even under the action of dissipation. in contrast, the local entanglement between two atoms inside each dissipative cavity attenuates due to the presence of unwanted environmental ***, the local coherence may show the same behavior as the remote ***, the system provides the steady state entanglement in various interaction regimes,particularly in the strong atom-cavity coupling and with relatively large detuning. more interestingly, our numerical analyses demonstrate that the system may show a memory effect due to the fact that the death and revival of the entanglement take place during the interaction. Our proposed model may find potential applications for the implementation of long distance quantum networks. in particular, it facilitates the distribution of quantum resources between the nodes of large-scale quantum networks for secure communication.

关键词： remote entanglement and coherence atomic dissipation steady state entanglement Bell-statemeasurement

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Transfer learning from synthetic data for open-circuit voltage curve reconstruction and state of health estimation of lithium-ion batteries from partial charging segments

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Energy and Ai 2024年第3期17卷 80-97页

作者： Tobias Hofmann Jacob Hamar Bastian mager Simon Erhard Jan Philipp Schmidt Chair of systems Engineering for Electrical Energy Storage University of BayreuthWeiherstraße 26Bayreuth95448BavariaGermany BmW group Petuelring 130Munich80809BavariaGermany

Data-driven models for battery state estimation require extensive experimental training data,which may not be available or suitable for specific tasks like open-circuit voltage(OCV)reconstruction and subsequent state of health(SOH)*** study addresses this issue by developing a transfer-learning-based OCV reconstruction model using a temporal convolutional long short-term memory(TCN-LSTm)network trained on synthetic data from an automotive nickel cobalt aluminium oxide(NCA)cell generated through a mechanistic model *** data consists of voltage curves at constant temperature,C-rates between C/30 to 1C,and a SOH-range from 70%to 100%.The model is refined via Bayesian optimization and then applied to four use cases with reduced experimental nickel manganese cobalt oxide(NmC)cell training data for higher use *** TL models’performances are compared with models trained solely on experimental data,focusing on different C-rates and voltage *** results demonstrate that the OCV reconstruction mean absolute error(mAE)within the average battery electric vehicle(BEV)home charging window(30%to 85%state of charge(SOC))is less than 22 mV for the first three use cases across all *** SOH estimated from the reconstructed OCV exhibits an mean absolute percentage error(mAPE)below 2.2%for these *** study further investigates the impact of the source domain on TL by incorporating two additional synthetic datasets,a lithium iron phosphate(LFP)cell and an entirely artificial,non-existing,cell,showing that solely the shifting and scaling of gradient changes in the charging curve suffice to transfer knowledge,even between different cell chemistries.A key limitation with respect to extrapolation capability is identified and evidenced in our fourth use case,where the absence of such comprehensive data hindered the TL process.

关键词： Lithium-ion battery State of health estimation Transfer learning OCV curve Partial charging Synthetic data

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Detection of Oscillations in Process Control Loops From Visual image Space Using Deep Convolutional Networks

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iEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 982-995页

作者： Tao Wang Qiming Chen Xun Lang Lei Xie Peng Li Hongye Su the Department of Electronic Engineering the School of InformationYunnan UniversityKunming 650091China DAmO Academy Alibaba GroupHangzhou 311100China the State Key Laboratory of industrial Control Technology Institute of Cyber-Systems and ControlZhejiang UniversityHangzhou 310027China

Oscillation detection has been a hot research topic in industries due to the high incidence of oscillation loops and their negative impact on plant *** numerous automatic detection techniques have been proposed,most of them can only address part of the practical *** oscillation is heuristically defined as a visually apparent periodic ***,manual visual inspection is labor-intensive and prone to missed *** neural networks(CNNs),inspired by animal visual systems,have been raised with powerful feature extraction *** this work,an exploration of the typical CNN models for visual oscillation detection is ***,we tested mobileNet-V1,ShuffleNet-V2,Efficient Net-B0,and GhostNet models,and found that such a visual framework is well-suited for oscillation *** feasibility and validity of this framework are verified utilizing extensive numerical and industrial *** with state-of-theart oscillation detectors,the suggested framework is more straightforward and more robust to noise and *** addition,this framework generalizes well and is capable of handling features that are not present in the training data,such as multiple oscillations and outliers.

关键词： Convolutional neural networks(CNNs) deep learning image processing oscillation detection process industries

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Evolutionary multi-Tasking Optimization for High-Efficiency Time Series Data Clustering

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Tsinghua Science and Technology 2024年第2期29卷 343-355页

作者： Rui Wang Wenhua Li Kaili Shen Tao Zhang Xiangke Liao Xiangjiang Laboratory Changsha 410205China College of systems Engineering National University of Defense TechnologyChangsha 410073China Ant group Co. Ltd.Hangzhou 310000China College of Computer Science and Technology NUDTChangsha 410073China

Time series clustering is a challenging problem due to the large-volume,high-dimensional,and warping characteristics of time series *** clustering methods often use a single criterion or distance measure,which may not capture all the features of the *** paper proposes a novel method for time series clustering based on evolutionary multi-tasking optimization,termed i-mFEA,which uses an improved multifactorial evolutionary algorithm to optimize multiple clustering tasks simultaneously,each with a different validity index or distance ***,i-mFEA can produce diverse and robust clustering solutions that satisfy various preferences of *** on two artificial datasets show that i-mFEA outperforms single-objective evolutionary algorithms and traditional clustering methods in terms of convergence speed and clustering *** paper also discusses how i-mFEA can address two long-standing issues in time series clustering:the choice of appropriate similarity measure and the number of clusters.

关键词： time series clustering evolutionary multi-tasking multifactorial optimization clustering validity index distance measure

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