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Journal of Meteorological Research 2017年第5期31卷 955-964页

作者： xiang li hongrang he chaohui chen ziqing miao shigang bai college of meteorology and oceanography pla university of science and technologyNanjing 211101 nanjing joint center of atmospheric research Nanjing 210009 pla troop 96219 Kunming 650200 pla troop 96319 Puning 515347

A convection-allowing ensemble forecast experiment on a squall line was conducted based on the breeding growth mode （BGM）. Meanwhile, the probability matched mean （PMM） and neighborhood ensemble probability （NEP） methods were used to optimize the associated precipitation forecast. The ensemble forecast predicted the precipita- tion tendency accurately, which was closer to the observation than in the control forecast. For heavy rainfall, the pre- cipitation center produced by the ensemble forecast was also better. The Fractions Skill Score （FSS） results indicated that the ensemble mean was skillful in light rainfall, while the PMM produced better probability distribution of pre- cipitation for heavy rainfall. Preliminary results demonstrated that convection-allowing ensemble forecast could im- prove precipitation forecast skill through providing valuable probability forecasts. It is necessary to employ new methods, such as the PMM and NEP, to generate precipitation probability forecasts. Nonetheless, the lack of spread and the overprediction of precipitation by the ensemble members are still problems that need to be solved.

关键词： convection-allowing ensemble forecast breeding growth mode (BGM) precipitation optimization prob-ability matched mean (PMM) neighborhood ensemble probability (NEP) Fractions Skill Score (FSS)

DR-IS: Dynamic Response Incremental Scheduling in Time-Sensitive Network

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China Communications 2024年第10期 28-42页

作者： Pei Jinchuan Hu Yuxiang Tian Le Li Ziyong pla Strategic Support Force Information Engineering University

Time-Sensitive Network(TSN) with deterministic transmission capability is increasingly used in many emerging fields. It mainly guarantees the Quality of Service(QoS) of applications with strict requirements on time and security. One of the core features of TSN is traffic scheduling with bounded low delay in the network. However, traffic scheduling schemes in TSN are usually synthesized offline and lack dynamism. To implement incremental scheduling of newly arrived traffic in TSN, we propose a Dynamic Response Incremental Scheduling(DR-IS)method for time-sensitive traffic and deploy it on a software-defined time-sensitive network *** the premise of meeting the traffic scheduling requirements, we adopt two modes, traffic shift and traffic exchange, to dynamically adjust the time slot injection position of the traffic in the original scheme,and determine the sending offset time of the new timesensitive traffic to minimize the global traffic transmission jitter. The evaluation results show that DRIS method can effectively control the large increase of traffic transmission jitter in incremental scheduling without affecting the transmission delay, thus realizing the dynamic incremental scheduling of time-sensitive traffic in TSN.

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Effects of Sea Spray Evaporation and Dissipative Heating on Intensity and Structure of Tropical Cyclone

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Advances in Atmospheric Sciences 2012年第4期29卷 810-822页

作者：程小平费建芳黄小刚郑静 Institute of Meteorology PLA University of Science and Technology 73061 troop of pla

To examine effects of sea spray evaporation and dissipative heating on structure and intensity of a real tropical cyclone, the sea spray flux parameterization scheme was incorporated into the fifth-generation Penn- sylvania State University National Center for Atmospheric Research Mesoscale Model （MM5）. Sensitivity tests were performed with varying the spray source function intensities and with and without dissipation heating. The numerical results indicate that sea spray evaporation increases the interfaeial sensible heat flux, which is increased by 16% for the moderate spray and 47% for the heavy spray, but has little effect on the interfaeial latent heat flux. The net effect of sea spray evaporation is to decrease the total sensible heat flux and to increase the total latent heat flux. The total enthalpy flux is increased by 1% and 12% with moderate and strong spray amounts, respectively. Consistent with these results, the intensity of the tropical cyclone is increased by 5% and 16% in maximum 10-m wind speed, respectively, due to sea spray evapora- tion. Sea spray evaporation and dissipative heating modify the tropical cyclone structure in important but complex ways. The effect of sea spray on the near-surface temperature and moisture depends on the spray amounts and its location within the tropical cyclone. Within the high-wind region of a tropical cyclone, the lower atmosphere becomes cooler and moister due to the evaporation of sea spray. However, the dissipative heating offsets the cooling due to sea spray evaporation, which makes the lower atmosphere warmer.

关键词： sea spray dissipative heat tropical cyclone

SPATIAL VARIATION OF WINTER SEA SURFACE TEMPERATURE IN NORTH PACIFIC AND ITS RELATION TO ATMOSPHERIC OSCILLATION MODES

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Journal of Tropical Meteorology 2012年第3期18卷 377-386页

作者：吕庆平张立凤朱坤 Institute of Meteorology PLA University of Science and Technology 92919 troop of pla

The spatial variation of sea surface temperature anomalies(SSTA) in the North Pacific Ocean during winter is investigated using the EOF decomposition *** first two main modes of SSTA are associated with Pacific Decadal Oscillation(PDO) mode and North Pacific Gyre Oscillation(NPGO) mode,***,the first mode(PDO) is switched to the second mode(NPGO),a dominant mode after *** mechanism of the modes' transition is *** the two oceanic modes are forced by the Aleutian Low(AL) and North Pacific Oscillation(NPO) modes,the AR-1 model is further used to examine the possible effect and mechanism of AL and NPO in generating the PDO and *** results show that compared to the NPO,the AL plays a more important role in generating the NPGO mode since the ***,both the AL and NPO affect the PDO mode since the 1980s.

关键词： North Pacific sea surface temperature sea level pressure climate mode variation

Passive target tracking with intermittent measurement based on random finite set

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Journal of Central South University 2014年第6期21卷 2282-2291页

作者：罗小波范红旗宋志勇付强 ATR Key Laboratory National University of Defense Technology pla No 96363 Troop

In the tracking problem for the maritime radiation source by a passive sensor,there are three main difficulties,i.e.,the poor observability of the radiation source,the detection uncertainty(false and missed detections)and the uncertainty of the target appearing/disappearing in the field of *** difficulties can make the establishment or maintenance of the radiation source target track *** incorporating the elevation information of the passive sensor into the automatic bearings-only tracking(BOT)and consolidating these uncertainties under the framework of random finite set(RFS),a novel approach for tracking maritime radiation source target with intermittent measurement was *** the RFS framework,the target state was represented as a set that can take on either an empty set or a singleton; meanwhile,the measurement uncertainty was modeled as a Bernoulli random finite ***,the elevation information of the sensor platform was introduced to ensure observability of passive measurements and obtain the unique target *** experiments verify the validity of the proposed approach for tracking maritime radiation source and demonstrate the superiority of the proposed approach in comparison with the traditional integrated probabilistic data association(IPDA)*** tracking performance under different conditions,particularly involving different existence probabilities and different appearance durations of the target,indicates that the method to solve our problem is robust and effective.

关键词： passive target tracking maritime target joint detection and tracking intermittent measurement random finite set poor observability

Characteristics of the Asian–Pacific Oscillation in Boreal Summer Simulated by BCC_CSM with Different Horizontal Resolutions

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Advances in Atmospheric Sciences 2016年第12期33卷 1401-1412页

作者： Yazhou ZHANG Zhijie LIAO Yaocun ZHANG Feng NIE School of Atmospheric Sciences Nanjing UniversityNanjing 210023 pla 61936 troop Haikou 571100

The summer Asian-Pacific Oscillation （APO） is a major teleconnection pattern that reflects the zonal thermal contrast between East Asia and the North Pacific in the upper troposphere. The performance of Beijing Climate Center Climate System Models （BCC_CSMs） with different horizontal resolutions, i.e., BCC_CSM1.1 and BCC_CSM1.1 （m）, in reproducing APO interannual variability, APO-related precipitation anomalies, and associated atmospheric circulation anomalies, is evaluated. The results show that BCC_CSMI.I（m） can successfully capture the interannual variability of the summer APO index. It is also more capable in reproducing the APO＇s spatial pattern, compared to BCC_CSMI.1, due to its higher horizontal resolution. Associated with a positive APO index, the northward-shifted and intensified South Asian high, strengthened extratropical westerly jet, and tropical easterly jet in the upper troposphere, as well as the southwesterly monsoonal flow over North Africa and the Indian Ocean in the lower troposphere, are realistically represented by BCC_CSM1.1 （m）, leading to an improvement in reproducing the increased precipitation over tropical North Africa, South Asia, and East Asia, as well as the decreased precipitation over subtropical North Africa, Japan, and North America. In contrast, these features are less consistent with observations when simulated by BCC_CSM1.1. Regression analysis further indicates that surface temperature anomalies over the North Pacific and the southern and western flanks of the Tibetan plateau are reasonably reproduced by BCC_CSM 1.1 （m）, which contributes to the substantial improvement in the simulation of the characteristics of summer APO compared to that of BCC_CSM1.1.

关键词： Asian-Pacific Oscillation BCC_CSM horizontal resolution simulation

Investigation of a semi-empirical load model of natural gas explosion in vented spaces

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Journal of Safety Science and Resilience 2021年第3期2卷 157-171页

作者： Shigang Yang Jiongwei Cai Ya Yang Qin Fang Qi Bao Senpei Wang National Defense College of Engineering Army Engineering University of PLANanjing 210007China 73021 troop of pla Hangzhou 310012China Naval Command College of pla Nanjing 210016China

Due to the influence of many factors,the overpressure-time history load model of vented gas explosions is difficult to describe and is not conducive to further structural *** on vented gas explosion test data,this paper obtains three typical overpressure-time history curves and puts forward a new semi-empirical model-double hump model that considers gas concentration and venting pressure,and gives a formula for peak pressure and overpressure-time history *** scientificity of the model is then verified by the total impulse in the *** model is able directly reflect the load characteristics,provide reference for calculating key parameters of a vented gas explosion and provide information on the structural response under the *** model thereby has the potential to help reduce the impact of gas explosion disasters.

关键词： Vented gas explosion Load model Overpressure-time history Gas concentration Venting pressure

Mature typhoon “cloud gyro” model and numerical simulation study

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Science China Earth Sciences 2020年第5期63卷 749-756页

作者： Xiaogang HUANG Xiangcheng LI Xiaoping CHENG Chenxi ZHANG Juli DING College of Meteorology and Oceanography National University of Defense TechnologyNanjing 211101China pla troop 92664 Haiyang 265100China

Due to the coarse temporal resolution of the best track databases for typhoons,some small-scale characteristics of typhoon motion have been *** order to reveal the fine features of typhoon motion,the dense cloud within the radius of maximum wind(RMW)of mature typhoons,defined as a“cloud gyro”that simultaneously spins around its own rotational axis and precesses around the vertical axis,is approximated to a rigid *** on the principles of gyrodynamics,the derived mathematical model of a typhoon track indicates that typhoon movement is composed of translational motion governed by the steering flow and superimposed precessional motion that manifests as the inherent characteristics of typhoon tracks,especially with the external *** temporal resolution numerical simulation of a real case verifies the conclusion of this study,which is that the smaller the RMW,the larger the tangential wind speed or the larger the external torque,and the more obviously precessional motion manifests.

关键词： Mature typhoon Cloud gyro Precession angular velocity

Range anomaly suppression based on neighborhood pixels detection in ladar range images

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Journal of Systems Engineering and Electronics 2013年第1期24卷 68-75页

作者： Mingbo Zhao Jun He Zaiqi Lu Qiang Fu Automatic Target Recognition Key Laboratory School of Electronic Science and EngineeringNational University of Defense Technology No.93246 troop of the pla

Research on the range anomaly suppression algorithm in laser radar （ladar） range images is significant in the application and development of ladar. But most of existing algorithms cannot protect the edge and linear target well while suppressing the range anomaly. Aiming at this problem, the differences among the edge, linear target, and range anomaly are analyzed and a novel algo- rithm based on neighborhood pixels detection is proposed. Firstly, the range differences between current pixel and its neighborhood pixels are calculated. Then, the number of neighborhood pixels is detected by the range difference threshold. Finally, whether the current pixel is a range anomaly is distinguished by the neighbor- hood pixel number threshold. Experimental results show that the new algorithm not only has a better range anomaly suppression performance and higher efficiency, but also protects the edge and linear target preferably compared with other algorithms.

关键词： image processing range anomaly suppression neigh-borhood p xe s detection linear target laser radar (ladar).

Application of Gaussian Weight to Improve Perturbation Features of Convection-Permitting Ensemble Forecast Based on Local Breeding of Growing Modes

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Journal of Meteorological Research 2021年第3期35卷 490-504页

作者： Kun LI Chaohui CHEN Hongrang HE Ru YANG Yi LI Yongqiang JIANG College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073 pla troop 95112 Foshan 528000

Local breeding of growing modes(LBGM)is a method used to generate initial condition perturbation(ICP)for convection-permitting ensemble *** weights(EWs)are usually presumed in LBGM during the localization of ICP,without considering different contributions of the grid points within the local *** address this problem,Gaussian weights(GWs)are proposed in this study,which can accommodate the varied influences of the grids inside the local radius on the central grid through a Gaussian ***,two convection-permitting ensemble forecast experiments based on LBGM with GWs and EWs are compared and analyzed respectively for two squall line *** results showed that the use of the GWs intensified the local characteristics of the ICP and made the distribution of the ICP fields more *** energy spectrum of the ICP indicated that there could be more large-scale information in the ICP by using the *** addition,mesoscale information also improved *** forecast of nonprecipitation variables,GWs improved the relationship between the root-mean-square error and the spread and contributed to the forecasting accuracy of wind,temperature,geopotential height,and *** the precipitation forecast,GWs simulated the precipitation structure successfully and provided better probability forecasting during the evolution of the two squall line processes than the EWs.

关键词： local breeding of growing modes(LBGM) convection-permitting ensemble Gaussian weight(GW) initial condition perturbation(ICP)