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Study on video intelligent early warning and tracking system based on ARM
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作者 刘岩松 Xu Yihong Xing jianping 《High Technology Letters》 EI CAS 2016年第3期266-272,共7页
The protrusion of the planning of numerical intelligent early-warning and tracking system in this study which can ease triggerman's work strength,lay the next generation intelligence supervision system foundation ... The protrusion of the planning of numerical intelligent early-warning and tracking system in this study which can ease triggerman's work strength,lay the next generation intelligence supervision system foundation and expand effectively the video resources use etc. In the numerical intelligent early-warning matrix sub-system,the authors have designed a kind dual-core system which includes both ARM and DSP,and designed detailedly traffic dynamics affairs early-warning arithmetic which bases on that system. And then,this system will carry quickly on fixing the right position of license plate,correcting the inclination degree of license plate,and thinning it to get the number of this license and severity grade. Secondly,in the rotated dome camera sub-system,the authors have designed three-dimensional trajectory mathematical model which makes use of a fuzzy PID controller to achieve the high- speed track. At last,Simulation shows that the proposed control method has high profile tracking precision,accuracy and robustness of the disturbance. 展开更多
关键词 embedded dual-core system intelligent early warning accident recognition tracking and monitoring simulation
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Sand-dust storms in China: temporal-spatial distribution and tracks of source lands 被引量:11
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作者 QIU Xin-fa1, ZENG Yan2, MIAO Qi-long2 (1. Urban & Resource Department, Nanjing University, Nanjing 210009, China 2. Department of Environmental Science, Nanjing Institute of Meteorology, Nanjing 210044, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第3期253-260,共9页
Sand-dust storm is a special natural disaster that frequently occurs in deserts and their surrounding areas. With the data published onSurface Meteorological Monthly Bulletin andSurface Chart during 1971–1996, the te... Sand-dust storm is a special natural disaster that frequently occurs in deserts and their surrounding areas. With the data published onSurface Meteorological Monthly Bulletin andSurface Chart during 1971–1996, the temporal-spatial distribution and annual variation of sand-dust storms are analyzed on the basis of the case study of atmospheric processes. Furthermore, the tracks and source areas of sand-dust storms are determined with the aid of GIS. The results show that except some parts of Qinghai Province and Inner Mongolia as well as Beijing, sand-dust storms decrease apparently in time and space in recent decades in China. Sand-dust storms occur most frequently in spring, especially in April. According to their source areas, sand-dust storms are classified into two types, i.e., the inner-source and outer-source sand-dust storms. Most of the outer-source sand-dust storms move along the north and west tracks. The north-track outer-source sand-dust storms always intrude into China across the Sino-Mongolian border from Hami, a city in the eastern part ofXinjiang, to Xilin Gol, a league in Inner Mongolia, while the west-track ones intrude into China from both southern and northern Xinjiang. The source lands of inner-source sand-dust storms concentrate in the Taklimakan Desert and its surrounding areas in southern Xinjiang, southern part of the Junggar Basin in north of Xinjiang, the Hexi Corridor in western Gansu Province, the dry deserts of Inner Mongolia and the Qaidam Basin in Qinghai. 展开更多
关键词 sand-dust storm temporal-spatial distribution TRACKS source lands
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SAMPLE OPTIMIZATION OF ENSEMBLE FORECAST TO SIMULATE TROPICAL STORMS(MERBOK, MAWAR, AND GUCHOL) USING THE OBSERVED TRACK 被引量:1
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作者 LI Ji-hang GAO Yu-dong +1 位作者 WAN Qi-lin ZHANG Xu-bin 《Journal of Tropical Meteorology》 SCIE 2020年第1期14-26,共13页
Nowadays,ensemble forecasting is popular in numerical weather prediction(NWP).However,an ensemble may not produce a perfect Gaussian probability distribution due to limited members and the fact that some members signi... Nowadays,ensemble forecasting is popular in numerical weather prediction(NWP).However,an ensemble may not produce a perfect Gaussian probability distribution due to limited members and the fact that some members significantly deviate from the true atmospheric state.Therefore,event samples with small probabilities may downgrade the accuracy of an ensemble forecast.In this study,the evolution of tropical storms(weak typhoon)was investigated and an observed tropical storm track was used to limit the probability distribution of samples.The ensemble forecast method used pure observation data instead of assimilated data.In addition,the prediction results for three tropical storm systems,Merbok,Mawar,and Guchol,showed that track and intensity errors could be reduced through sample optimization.In the research,the vertical structures of these tropical storms were compared,and the existence of different thermal structures was discovered.One possible reason for structural differences is sample optimization,and it may affect storm intensity and track. 展开更多
关键词 ensemble forecast sample optimization tropical storm observed track
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Real-time lane departure warning system based on principal component analysis of grayscale distribution and risk evaluation model 被引量:4
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作者 张伟伟 宋晓琳 张桂香 《Journal of Central South University》 SCIE EI CAS 2014年第4期1633-1642,共10页
A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and... A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and then each search bar was tracked using Kalman filter between frames. The lane detection performance was evaluated and demonstrated in ways of receiver operating characteristic, dice similarity coefficient and real-time performance. For lane departure detection, a lane departure risk evaluation model based on lasting time and frequency was effectively executed on the ARM-based platform. Experimental results indicate that the algorithm generates satisfactory lane detection results under different traffic and lighting conditions, and the proposed warning mechanism sends effective warning signals, avoiding most false warning. 展开更多
关键词 lane departure warning system lane detection lane tracking principal component analysis risk evaluation model ARM-based real-time system
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OBJECTIVE CLASSIFICATION OF THE TRACKS OF TROPICAL STORMS IN THE BAY OF BENGAL 被引量:2
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作者 林志强 边巴扎西 +1 位作者 文胜军 周振波 《Journal of Tropical Meteorology》 SCIE 2015年第3期222-231,共10页
An objective analysis of tropical cyclone tracks is performed, with which the tracks of 131 tropical storms(TSs) in 1972-2011 are separated into three types that move west-, north- and northwestward, denoted as Types ... An objective analysis of tropical cyclone tracks is performed, with which the tracks of 131 tropical storms(TSs) in 1972-2011 are separated into three types that move west-, north- and northwestward, denoted as Types A, B and C, respectively. Type A(21 TSs and 16% of total) has the origin in the southwestern Bay of Bengal, with the TS in a unimodal distribution as its seasonal feature, occurring mainly in autumn; 18 of the 21 TSs(taking up 90%) land mostly on the western Bay coast(west of 85°E); 5% of Type-A TSs attains the wind speed of >42.7 to 48.9 m/s. Type A has little or no effect on Tibet. Type B(74 TSs, 56.6% of the total) has its preferable origin in the central Bay of Bengal, with the TS in a bimodal distribution as its seasonal pattern. This type denotes the travel in the north in spring,with the landfall of 67 of the 74 TSs(accounting for 91%) mainly on the middle coast of the Bay(85° to 95°E), and19% of the TSs reaching the wind velocity of >42.7 to 48.9 m/s, which exert great effect on Tibet and it is this TS track that gives strong precipitation on its way through this region. Type C(36 TSs, 27.5% of the total) has its main origin in the southern part of the bay, and these TSs are formed largely in autumn, moving in the northwest direction,and 23 of the 36 TSs(64%) land mostly on the western Bay coast, lasting for a longer time, with almost no impact upon Tibet. 展开更多
关键词 Bay of Bengal tropical storm storm track objective analysis Tibetan Plateau
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Synchronization of Radar Observations with Multi-Scale Storm Tracking 被引量:2
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作者 杨洪平 Jian ZHANG Carrie LANGSTON 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第1期78-86,共9页
The 3-D radar reflectivity data has become increasingly important for use in data assimilation towards convective scale numerical weather prediction as well as next generation precipitation estimation. Typically, refl... The 3-D radar reflectivity data has become increasingly important for use in data assimilation towards convective scale numerical weather prediction as well as next generation precipitation estimation. Typically, reflectivity data from multiple radars are objectively analyzed and mosaiced onto a regional 3-D Cartesian grid prior to being assimilated into the models. One multi-radar observations is the synchronization of all of the scientific issues associated with the mosaic of the observations. Since radar data is usually rapidly updated (-every 5-10 min), it is common in current multi-radar mosaic techniques to combine multiple radar' observations within a time window by assunfing that the storms are steady within the window. The assumption holds well for slow evolving precipitation systems, but for fast evolving convective storms, this assumption may be violated and the mosaic of radar observations at different times may result in inaccurate storm structure depictions. This study investigates the impact of synchronization on storm structures in multiple radar data analyses using a multi-scale storm tracking algorithm. 展开更多
关键词 SYNCHRONIZATION RADAR multi-scale storm tracking
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Two Modes and Their Seasonal and Interannual Variation of the Baroclinic Waves/Storm Tracks over the Wintertime North Pacific 被引量:1
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作者 JIANG Yuxin TAN Benkui 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第9期1244-1254,共11页
In this study,a newly developed method,termed moving empirical orthogonal function analysis(MEOF),is applied to the study of midlatitude baroclinic waves over the wintertime North Pacific from 1979 to 2009.It is sho... In this study,a newly developed method,termed moving empirical orthogonal function analysis(MEOF),is applied to the study of midlatitude baroclinic waves over the wintertime North Pacific from 1979 to 2009.It is shown that when the daily,high-pass filtered(2–10 days) meridional wind at 250 h Pa is chosen as the variable of the MEOF analysis,typical features of baroclinic waves/storm tracks over the wintertime North Pacific can be well described by this method.It is found that the first two leading modes of the MEOF analysis,MEOF1 and MEOF2,assume quite different patterns.MEOF1 takes the form of a single wave train running in the east–west direction along 40°N,while MEOF2 is a double wave train pattern running in the east–west direction along 50°N and 30°N,respectively.The shift composites of various anomalous fields based on MEOF1 and MEOF2 assume typical baroclinic wave features.MEOF1 represents a primary storm track pulsing with an intrinsic time scale of two days.It shows significant "midwinter suppression" and apparent interannual variability.It is stronger after the mid-1990 s than before the mid-1990 s.MEOF2 represents a double-branch storm track,also with an intrinsic time scale of approximately two days,running along 50°N and 30°N,respectively.It shows no apparent seasonal variation,but its interannual and decadal variation is quite clear.It oscillates with larger amplitude and longer periods after the mid-1990 s than before the mid-1990 s,and is heavily modulated by El Ni n°o–Southern Oscillation(ENSO). 展开更多
关键词 baroclinic waves Pacific storm tracks MEOF analysis ENSO
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Interannual and Decadal Variability of the North Pacific Blocking and Its Relationship to SST, Teleconnection and Storm Tracks 被引量:1
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作者 黄菲 周发琇 钱筱丹 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2002年第5期807-820,共14页
Climalological features of mid-latitude blocking occurring over the North Pacific Ocean during 52 winters (December to February) of 1948/1949-1999/2000 are statistically analyzed based on NCEP/ NCAR reanalysis data. S... Climalological features of mid-latitude blocking occurring over the North Pacific Ocean during 52 winters (December to February) of 1948/1949-1999/2000 are statistically analyzed based on NCEP/ NCAR reanalysis data. Significant interannual variation with a period of about 3-7 years as well as decadal variability is found by wavelet analysis and power spectrum analysis. A decreasing trend of the 2-7 year bandscale-averaged variance occurs throughout the 52 years and an abrupt shift from a higher state to a lower state during the 1970s is also found, which suggests an interdecadal variation of the North Pacific blocking. The possible relationship between the variability of blocking and sea surface temperature (SST), storm tracks and teleconnection are shown using composite analysis. In strong blocking anomaly winter (SBW), the geopotential height anomaly at 500 hPa exhibits a typical PNA (Pacific-North American)-like wave-train pattern in the North Pacific. The storm tracks, representing the activity of transient eddies, extend northeastward to the western coast of North America along the mid latitudes of about 40°-50°N, with the SST anomaly exhibiting a Pacific decadal oscillation (PDO) mode at mid-latitude and a La Ni&#241;a-like pattern along the equator. Contrasting features appear in weak blocking anomaly winter (WBW). 展开更多
关键词 north Pacific blocking TELECONNECTION SST anomaly storm tracks
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Impacts of Oceanic Fronts and Eddies in the Kuroshio-Oyashio Extension Region on the Atmospheric General Circulation and Storm Track 被引量:2
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作者 Guidi ZHOU Xuhua CHENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第1期22-54,共33页
This paper reviews the progress in our understanding of the atmospheric response to midlatitude oceanic fronts and eddies,emphasizing the Kuroshio-Oyashio Extension(KOE)region.Oceanic perturbations of interest consist... This paper reviews the progress in our understanding of the atmospheric response to midlatitude oceanic fronts and eddies,emphasizing the Kuroshio-Oyashio Extension(KOE)region.Oceanic perturbations of interest consist of sharp oceanic fronts,temperature anomalies associated with mesoscale eddies,and to some extent even higher-frequency submesoscale variability.The focus is on the free atmosphere above the boundary layer.As the midlatitude atmosphere is dominated by vigorous transient eddy activity in the storm track,the response of both the time-mean flow and the storm track is assessed.The storm track response arguably overwhelms the mean-flow response and makes the latter hard to detect from observations.Oceanic frontal impacts on the mesoscale structures of individual synoptic storms are discussed,followed by the role of oceanic fronts in maintaining the storm track as a whole.KOE fronts exhibit significant decadal variability and can therefore presumably modulate the storm track.Relevant studies are summarized and intercompared.Current understanding has advanced greatly but is still subject to large uncertainties arising from inadequate data resolution and other factors.Recent modeling studies highlighted the importance of mesoscale eddies and probably even submesoscale processes in maintaining the storm track but confirmation and validation are still needed.Moreover,the atmospheric response can potentially provide a feedback mechanism for the North Pacific climate.By reviewing the above aspects,we envision that future research shall focus more upon the interaction between smaller-scale oceanic processes(fronts,eddies,submesoscale features)and atmospheric processes(fronts,extratropical cyclones etc.),in an integrated way,within the context of different climate background states. 展开更多
关键词 atmospheric response storm track oceanic front mesoscale eddy SUBMESOSCALE Kuroshio-Oyashio Extension
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Mean Flow–Storm Track Relationship and Rossby Wave Breaking in Two Types of El-Nino 被引量:1
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作者 LIU Chengji REN Xuejuan YANG Xiuqun 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第1期197-210,共14页
The features of large-scale circulation, storm tracks and the dynamical relationship between them were examined by investigating Rossby wave breaking (RWB) processes associated with Eastern Pacific (EP) and Centra... The features of large-scale circulation, storm tracks and the dynamical relationship between them were examined by investigating Rossby wave breaking (RWB) processes associated with Eastern Pacific (EP) and Central Pacific (CP) E1-Nifio. During EP E1-Nino, the geopotential height anomaly at 500 hPa (Z500) exhibits a Pacific-North America (PNA) pattern. During CP EI-Nifio, the Z500 anomaly shows a north positive-south negative pattern over the North Pacific. The anomalous distributions of baroclinicity and storm track are consistent with those of upper-level zonal wind for both EP and CP EI-Nino, suggesting impacts of mean flow on storm track variability. Anticyclonic wave breaking (AWB) oczurs less frequently in EP EI-Nino years, while cyclonic wave breaking (CWB) occurs more frequently in CP EI-Nino years over the North Pacific sector. Outside the North Pacific, more CWB events occur over North America during EP Ei-NiNo. When AWB events occur less frequently over the North Pacific during EP EI-Nino, Z500 decreases locally and the zonal wind is strengthened (weakened) to the south (north). This is because AWB events reflect a monopoie high anomaly at the centroid of breaking events. When CWB events occur more frequently over the North Pacific under CP EI-Nino conditions, and over North America under EP EI-Nino condition, Z500 increases (decreases) to the northeast (southwest), since CWB events are related to a northeast-southwest dipole Z500 anomaly. The anomalous RWB events act to invigorate and reinforce the circulation anomalies over the North Pacific-North America region linked with the two types of EI-Nino. 展开更多
关键词 central Pacific EI-Nino eastern Pacific El-Nifio large-scale circulation storm track Rossby wave breaking
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EXPERIMENTS TO TRACK STORMS USING MODERN OPTIMIZATION ALGORITHMS 被引量:1
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作者 李南 魏鸣 《Journal of Tropical Meteorology》 SCIE 2010年第3期280-291,共12页
Storm identification and tracking based on weather radar data are essential to nowcasting and severe weather warning. A new two-dimensional storm identification method simultaneously seeking in two directions is propo... Storm identification and tracking based on weather radar data are essential to nowcasting and severe weather warning. A new two-dimensional storm identification method simultaneously seeking in two directions is proposed, and identification results are used to discuss storm tracking algorithms. Three modern optimization algorithms (simulated annealing algorithm, genetic algorithm and ant colony algorithm) are tested to match storms in successive time intervals. Preliminary results indicate that the simulated annealing algorithm and ant colony algorithm are effective and have intuitionally adjustable parameters, whereas the genetic algorithm is unsatisfaetorily constrained by the mode of genetic operations Experiments provide not only the feasibility and characteristics of storm tracking with modern optimization algorithms, but also references for studies and applications in relevant fields. 展开更多
关键词 raw weather radar data storm identification and tracking optimization algorithms
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INFLUENCE ON NORTHERN PACIFIC STORM TRACK OF EQUATO-RIAL CENTRAL AND EASTERN PACIFIC SSTA DURING WINTER
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作者 朱伟军 孙照渤 +1 位作者 闵锦忠 彭加毅 《Journal of Tropical Meteorology》 SCIE 2000年第1期106-112,共5页
Singular value decomposition (SVD) is conducted of 15 winter tropical Pacific SST with 500 hPa filtered potential height variance over the northern Pacific storm track. It is shown that the first coupled mode obtained... Singular value decomposition (SVD) is conducted of 15 winter tropical Pacific SST with 500 hPa filtered potential height variance over the northern Pacific storm track. It is shown that the first coupled mode obtained depicts the effect on the track of SSTA over equatorial central and eastern Pacific. Further com-posite analysis indicates that the SSTA over there during winter can give rise to or invigorate PNA teleconnec-tion response pattern in 500 hPa height field which, in turn, exerts crucial influence on the interannual variabil-ity in vigor and east-west displacement of the Pacific storm track, especially over its central and eastern part. 展开更多
关键词 STORM track INTERANNUAL variability SVD analysis TELECONNECTION pattern
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The Linkage between Midwinter Suppression of the North Pacific Storm Track and Atmospheric Circulation Features in the Northern Hemisphere
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作者 Minghao YANG Chongyin LI +2 位作者 Xin LI Xiong CHEN Lifeng LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第3期502-518,共17页
The midwinter suppression(MWS) of the North Pacific storm track(NPST) has been an active research topic for decades. Based on the daily-mean NCEP/NCAR reanalysis from 1948 to 2018, this study investigates the MWS-rela... The midwinter suppression(MWS) of the North Pacific storm track(NPST) has been an active research topic for decades. Based on the daily-mean NCEP/NCAR reanalysis from 1948 to 2018, this study investigates the MWS-related atmospheric circulation characteristics in the Northern Hemisphere by regression analysis with respect to a new MWS index, which may shed more light on this difficult issue. The occurrence frequency of the MWS of the upper-tropospheric NPST is more than 0.8 after the mid-1980 s. The MWS is accompanied by significantly positive sea-level pressure anomalies in Eurasia and negative anomalies over the North Pacific, which correspond to a strengthened East Asian winter monsoon. The intensified East Asian trough and atmospheric blocking in the North Pacific as well as the significantly negative low-level air temperature anomalies, lying upstream of the MNPST, are expected to be distinctly associated with the MWS. However, the relationship between the MWS and low-level atmospheric baroclinicity is somewhat puzzling.From the diagnostics of the eddy energy budget, it is identified that the inefficiency of the barotropic energy conversion related to the barotropic governor mechanism does not favor the occurrence of the MWS. In contrast, weakened baroclinic energy conversion, buoyancy conversion, and generation of eddy available potential energy by diabatic heating are conducive to the occurrence of the MWS. In addition, Ural blocking in the upstream region of the MNPST may be another candidate mechanism associated with the MWS. 展开更多
关键词 midwinter suppression North Pacific storm track anomalous atmospheric circulation eddy energy budget
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Response of Flash Flood Early Warning Critical Rainfall to Storm Pattern in South Branch of Censhui Watershed
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作者 Changzhi Li Baozhao Yuan +2 位作者 Miao Zhang Changjun Liu Dongya Sun 《Journal of Environmental Science and Engineering(B)》 2015年第12期637-648,共12页
Critical rainfall estimation for early warning of rainstorm-induced flash flood is an inverse rainstorm-runoff process based on warning discharge threshold for a warning station of interest in a watershed. The key asp... Critical rainfall estimation for early warning of rainstorm-induced flash flood is an inverse rainstorm-runoff process based on warning discharge threshold for a warning station of interest in a watershed. The key aspects of critical rainfall include rainfall amount and rainfall duration. Storm pattern affects highly the estimation of critical rainfall. Using hydrological modeling technique with detailed sub-basin delineation and manual for design rainstorm-runoff computation, this study first introduced basic concept and analysis methods on critical rainfall for flash flood early warning, then, investigated the responses of flash flood warning critical rainfall to storm pattern. Taking south branch of Censhui watershed in China as an example, critical rainfall in case of typical storm patterns for early warning of rainstorm-induced flash flood were estimated at 3 warning stations. This research illustrates that storm pattern plays important role in the estimation of critical rainfall and enough attention should also be paid to storm pattern when making a decision on whether a warning to be issued or not. 展开更多
关键词 Flash flood early warning critical rainfall storm pattern response.
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Different response of North Pacific storm tracks in the upper and lower troposphere to jet strength
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作者 Chenming Ma Ming Bao 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第1期1-7,共7页
北太平洋风暴轴的深冬抑制表明风暴轴强度与斜压性之间的线性关系在冬季破裂,本研究基于1979-2019年冷季的再分析数据和拉格朗日跟踪算法,对比分析了高低层扰动的具体生长过程,结果表明太平洋急流的增强有利于高层扰动在急流核东北侧产... 北太平洋风暴轴的深冬抑制表明风暴轴强度与斜压性之间的线性关系在冬季破裂,本研究基于1979-2019年冷季的再分析数据和拉格朗日跟踪算法,对比分析了高低层扰动的具体生长过程,结果表明太平洋急流的增强有利于高层扰动在急流核东北侧产生,但却抑制其在西北太平洋的生成,在急流核上游产生的高层扰动在整个冷季都无法充分发展,只有在急流核下游产生的高层扰动才能正常生长且它们是构成高层太平洋风暴轴的主体,相比之下,低层扰动的生成区和生长区都与斜压区重合,并且它们的生成数量和局部增长率随着斜压性的增强而增强. 展开更多
关键词 深冬抑制 风暴轴 斜压性 生长过程 生成
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The Storm Tracks Response to Changes in Atmospheric Greenhouse Gas Concentration at the South of Brazil and Southwest Atlantic Ocean
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作者 Rose Ane Pereira De Freitas Fernanda Casagrande +2 位作者 Douglas Da Silva Lindemann Maria Angélica Gonçalves Cardoso Jeferson Prietsch Machado 《Atmospheric and Climate Sciences》 2019年第4期545-557,共13页
Here we investigate the ocean-atmosphere coupling and the contribution of the Sea Surface Temperature (SST) variations in: 1) Brazil-Malvinas Confluence (BMC) region, 2) Southwest Atlantic Ocean and 3) Southern Brazil... Here we investigate the ocean-atmosphere coupling and the contribution of the Sea Surface Temperature (SST) variations in: 1) Brazil-Malvinas Confluence (BMC) region, 2) Southwest Atlantic Ocean and 3) Southern Brazil. Numerical simulations of the ECHAM5/MPI-OM coupled ocean-atmosphere model were used to analyze the changes in the seasonal trajectory of the extratropical cyclones, in terms of intensification of physical mechanisms and implications for future scenarios. The numerical experiment for the future scenario considered an atmospheric CO2 concentration of approximately 770 ppm, which represents an increment of more than 350 ppm over the current values recorded by the Mauna Loa reference station. For this scenario, the results indicated a Storm Tracks (ST) displacement of 5° latitude toward south and changes of the meridional transport of sensible heat, close to 50°S. The increase in SST induces ST intensification and consequently an increase in the occurrence of extratropical cyclones. Overall, in the BMC region, we found a change in the pattern of cyclogenetic activity occurrence, with less frequent, but more intense events. On the Southern Brazilian region, the results of this study indicate increases in rainfall during summer months, whereas, a decrease in frequency and an increase in intensity were found for wintertime. We suggest that these changes could impact the climate dynamic of the Brazilian South coast, with a magnitude yet unknown. 展开更多
关键词 Storm Tracks Confluence Brazil-Malvinas Atlantic Ocean
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一次大暴雨中尺度短时强降水回波特征分析 被引量:2
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作者 洪丽霞 马中元 +2 位作者 洪俊 辛珂钰 范小军 《江西科学》 2024年第3期582-586,653,共6页
为了做好江西宜丰大暴雨天气的预警预报服务,使用常规天气图、宜丰自动站雨量、江西雷达拼图等资料,采用天气学、雷达气象学等原理,对2022年6月3日江西宜丰地区大暴雨过程进行分析。结果表明,通过对6月3日宜丰大暴雨年月日统计特征进行... 为了做好江西宜丰大暴雨天气的预警预报服务,使用常规天气图、宜丰自动站雨量、江西雷达拼图等资料,采用天气学、雷达气象学等原理,对2022年6月3日江西宜丰地区大暴雨过程进行分析。结果表明,通过对6月3日宜丰大暴雨年月日统计特征进行分析,1981—2022年宜丰每年大暴雨出现频次在0~2次,主要集中出现在6月份。宜丰此次大暴雨过程前期雨势不大,但由于云系发展和地形、环境等条件的影响,在6月3日08时小时雨强达到了65 mm,到了09时小时雨强达到最大的70 mm,造成了局地的超短时强降水。受低槽及低层切变东移影响,边界层及地面增温明显,动力抬升加强。850 hPa低涡东侧的切变线一直延伸至赣北北部,切变线南侧西南急流达到14 m/s,宜丰处在西南急流的左前方,同时地面辐合线稳定在宜丰附近并与低层切变耦合,导致辐合扰动加强,有利于强风暴在辐合线附近发生。回波形态为絮状回波带结构,絮状回波带包含着多个较强单体回波,影响宜丰的组合反射率CR回波最强达到50 dBZ,≥45 dBZ回波稳定在宜丰南部,为短时强降水的生成形成了非常有利的条件,随着回波顶高的升高,加强了该单体回波的降水效率,08时出现了小时雨强65 mm/h的超强降水。 展开更多
关键词 宜丰 短时强降水 雷达拼图回波特征 风暴跟踪信息
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医院传染病实时监控、预警和追踪管理系统的研发及应用效果追踪评价
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作者 钟土立 陈昂 +3 位作者 肖桐明 黄桑 陈珮莹 张文琪 《现代医院》 2024年第9期1439-1441,1445,共4页
目的通过研发“医院传染病实时监控、预警和追踪管理系统”,实现实时监测预警,生成报告卡,形成传染病个案追踪管理、全程闭环管理。方法选取2020年4月—2022年10月传染病报告22185例,与2022年11月—2024年5月传染病报告33640例,对比新... 目的通过研发“医院传染病实时监控、预警和追踪管理系统”,实现实时监测预警,生成报告卡,形成传染病个案追踪管理、全程闭环管理。方法选取2020年4月—2022年10月传染病报告22185例,与2022年11月—2024年5月传染病报告33640例,对比新的传染病预警管理系统上线前后19个月时间与上线前原传统传染病报告管理方式传染病报告管理情况,对比传染病报告率、传染病报告准确率、传染病报告及时性(时间)、传染病追踪成效、临床医务人员传染病报告满意度进行对比分析。结果新的医院传染病预警和追踪管理系统使用后,对传染病报告率、传染病报告准确率、传染病报告及时性、传染病追踪成效和临床医务人员传染病报告满意度成效对比差异均有统计学意义(P<0.05)。结论研发“医院传染病实时监控、预警和追踪管理系统”在传染病报告率、传染病报告准确率、传染病报告及时性、传染病追踪成效和临床医务人员传染病报告满意度成效均显著提高,具有实时、高效、准确的特点,预警和追踪管理效果良好,具有很好的推广价值。 展开更多
关键词 传染病 传染病预警 传染病追踪
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油气行业作业人员不安全行为智能预警方法探讨 被引量:2
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作者 胡瑾秋 陈传刚 +1 位作者 吴明远 胡洋柏 《世界石油工业》 2024年第2期83-90,共8页
油气行业涉及领域广,从业人员在作业过程中通常面临复杂的生产工艺、恶劣的工作环境及高强度的工作状态等,油气行业事故发生率常年居高不下,其中人为失误等事故原因所占比例超过70%。实现油气行业作业人员不安全行为的智能预警,对于减... 油气行业涉及领域广,从业人员在作业过程中通常面临复杂的生产工艺、恶劣的工作环境及高强度的工作状态等,油气行业事故发生率常年居高不下,其中人为失误等事故原因所占比例超过70%。实现油气行业作业人员不安全行为的智能预警,对于减少油气行业事故的发生具有重要意义。油气行业作业人员的不安全行为主要包括错误行为与安全隐患行为。针对作业人员的不安全行为识别和预警,目前主要采用人员检查、事后分析及视频监控等方法,但是上述方法分别存在无法实时识别作业人员的错误行为,无法识别和预警作业人员的安全隐患行为等。视线追踪技术是通过捕捉作业人员的注视点与注视时间的变化过程,从而判断作业人员当前工作状态的一项技术。该技术具有反应灵敏、准确度高、无死角与可穿戴等特点,在医疗健康、交通安全、心理学等领域均已有较好的应用。利用视线追踪技术在人员状态监测等方面的优势,将其引入到油气行业作业人员不安全行为的识别或预警方法研究,用以探讨在该领域实现作业人员不安全行为智能预警的可行性。 展开更多
关键词 油气行业 作业人员 不安全行为 视线追踪 智能预警
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基于HEC-RAS的陇南山地山洪灾害风险图优化研究
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作者 陶虎 方自刚 +1 位作者 樊娜娜 尚凯 《自然灾害学报》 CSCD 北大核心 2024年第4期34-47,共14页
短历时山洪是威胁陇南山地交通和村镇安全的重要灾害之一。为提高该地区防灾减灾能力,通过不同雨强计算出洪水淹没损失程度,利用洪水风险区划图指导当地群众预防山洪灾害具有重要的科学意义。基于HEC-RAS水文分析方法,结合GIS软件模拟... 短历时山洪是威胁陇南山地交通和村镇安全的重要灾害之一。为提高该地区防灾减灾能力,通过不同雨强计算出洪水淹没损失程度,利用洪水风险区划图指导当地群众预防山洪灾害具有重要的科学意义。基于HEC-RAS水文分析方法,结合GIS软件模拟了流域洪水淹没过程,以陇南山地蒲家沟为研究对象,在5、10、50、100 a一遇设计雨量条件下,综合考虑坡度、土地类型、损失率、水位和流速等多种因素,对传统洪水风险区划图进行优化。结果表明,相比传统方法绘制的风险区划图,优序图法优化后的风险区划图更加重视承灾体的受影响程度,且解决了传统风险区划图中小区域风险等级跨度大,风险等级难以定级的缺点。优化后的风险区划图,上中游无人区风险等级降低,下游人类活动区域风险等级更加明确。以马泉村王家咀为例,在50 a一遇的设计雨量下,传统方法绘制的风险区划图其划分结果涵盖5个风险等级,各区域面积差距不显著,难以确定最终的风险等级。而优序图法优化后的风险区划图划分结果更加集中,王家咀高风险区域面积不足中风险的4%,王家咀风险区域可以明确地定位到中风险。文中优序图法优化后的风险区划图在实用性和适应性上更具优势,可以为小流域山洪预警预报和防灾减灾工作提供帮助。 展开更多
关键词 山洪 设计暴雨 优序图法 山洪预警
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