期刊文献+
共找到24篇文章
< 1 2 >
每页显示 20 50 100
蒋介石与“五·二四”事件研究 被引量:1
1
作者 王永男 《台湾研究集刊》 CSSCI 北大核心 2017年第6期86-93,共8页
冷战时期,台美关系因"五·二四"事件遭遇挑战。"五·二四"事件爆发后,台美关系、接班人蒋经国、台湾国际"托管论"等因素均涉入其中,时刻影响着蒋介石的判断与决策。其中,台美关系一直是蒋介石处... 冷战时期,台美关系因"五·二四"事件遭遇挑战。"五·二四"事件爆发后,台美关系、接班人蒋经国、台湾国际"托管论"等因素均涉入其中,时刻影响着蒋介石的判断与决策。其中,台美关系一直是蒋介石处理该事件的主轴。为了稳固台美关系,实现"反攻大陆",蒋介石决定"祸引"中共。最终,蒋介石将案情定性为"匪谍"煽动案,并以政治强人的姿态全程控制与安排"匪谍"审理,使之得以"完满"解决。尽管如此,"五·二四"事件的发生对美台关系仍有创伤。 展开更多
关键词 蒋介石 “五·二四”事件 “暴动”
下载PDF
The Characteristics of Cloud-to-Ground Lightning Activity with Severe Thunderstorm Wind in South and North China 被引量:3
2
作者 YANG Xin-Lin SUN Jian-Hua 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第6期571-576,共6页
The characteristics of cloud-to-ground(CG) lightning activity with severe thunderstorm wind(STW) in South and North China are analyzed using CG lightning data, radar data, and serious weather reports. The percentage o... The characteristics of cloud-to-ground(CG) lightning activity with severe thunderstorm wind(STW) in South and North China are analyzed using CG lightning data, radar data, and serious weather reports. The percentage of positive CG(PCG) flashes with STW in North China is larger than that in South China. STW takes place during the period when the total CG and PCG density is increasing fastest. STW also occurs close to the high-value center of CG and PCG density. In North China, the CG and PCG density in the grid of STW maximizes approximately 20 minutes after the STW occurs; while in South China, the PCG density and percentage of PCG in the grid of STW maximizes about 10 minutes before the occurrence of STW. The high-value centers of CG density and PCG density in North China move slightly faster than those in South China, which is opposite to the rate of increasing CG activity. 展开更多
关键词 cloud-to-ground lightning severe thunderstorm wind severe convection
下载PDF
Statistical Analysis of Tropical Disturbances over the South China Sea During 1997-2006 被引量:1
3
作者 WANG Lei LAU Kai Hon 《Journal of Ocean University of China》 SCIE CAS 2011年第2期99-105,共7页
Tropical disturbances over the South China Sea (SCS) during the period of 1997-2006 are analyzed using the Tropical Storm and Hurricane WX products. A total of 158 tropical disturbances were formed over the SCS from 1... Tropical disturbances over the South China Sea (SCS) during the period of 1997-2006 are analyzed using the Tropical Storm and Hurricane WX products. A total of 158 tropical disturbances were formed over the SCS from 1997 to 2006, with 54 de-veloping tropical disturbances which developed into tropical depressions and 104 non-developing tropical disturbances which never developed into tropical depressions. The development rate of tropical disturbances into tropical depressions was 34.18% in these ten years. During the period of this study, total annual numbers of tropical disturbances and developing tropical disturbances over the SCS had significant decreasing trends; however, the development rate of tropical disturbances had an insignificant increasing trend. 展开更多
关键词 tropical disturbance South China Sea tropical cyclone
下载PDF
Investigating the initiation and propagation processes of convection in heavy precipitation over the western Sichuan Basin 被引量:3
4
作者 LI Qin YANG Shuai +1 位作者 CUI Xiao-Peng GAO Shou-Ting 《Atmospheric and Oceanic Science Letters》 CSCD 2017年第3期235-242,共8页
Heavy precipitation events occur often over the western Sichuan Basin in summer, near the transition zone between the Sichuan Basin and the steep terrain of the Tibetan Plateau. One such event -- a heavy precipitation... Heavy precipitation events occur often over the western Sichuan Basin in summer, near the transition zone between the Sichuan Basin and the steep terrain of the Tibetan Plateau. One such event -- a heavy precipitation process that occurred on 18-20 August 2010, with clear nocturnal peaks -- is chosen as a case to tentatively explore how the convection associated with convectivescale precipitation is initiated and propagated. By utilizing the vertical momentum equation from the viewpoint of separating perturbation pressure into dynamic and thermal parts, it is demonstrated that the vertical momentum is induced by the imbalance of several forces, including the dynamic/buoyant part of the perturbation pressure gradient force and the buoyancy force, with the latter dominating during the nocturnal-peak period. Although a negative value of the dynamic perturbation pressure gradient force partly offsets the positive buoyant forcing inside the strong updraft, the pattern of vertical motion tendency is largely attributable to its buoyancy because of its larger magnitude. Relative to the buoyancy component, the dynamic part of the vertical perturbation pressure gradient is also examined, revealing a smaller order of magnitude. Thus, it is the thermal effect that should be responsible for the initiation and propagation of convection. As for the convective-scale precipitation, it always presents a trailing morphology relative to the strong leading-side updraft. Furthermore, overlapping strong signals of vertical motion and its tendency point towards strong precipitation in the future. 展开更多
关键词 Heavy precipitation CONVECTION vertical momentum equation perturbation pressure equation
下载PDF
Assessing Post-Storm Forest Dynamics in the Pyrenees Using High-Resolution LIDAR Data and Aerial Photographs
5
作者 ángela BLáZQUEZ-CASADO José R.GONZáLEZ-OLABARRIA +3 位作者 Santiago MARTíN-ALCóN Ariadna JUST Mariló CABRé Lluís COLL 《Journal of Mountain Science》 SCIE CSCD 2015年第4期841-853,共13页
We evaluated how historical storm events have shaped the current forest landscape in three Pyrenean subalpine forests(NE Spain).For this purpose we related forest damage estimations obtained from multi-temporal aerial... We evaluated how historical storm events have shaped the current forest landscape in three Pyrenean subalpine forests(NE Spain).For this purpose we related forest damage estimations obtained from multi-temporal aerial photographic comparisons to the current forest typology generated from airborne Li DAR data, and we examined the role of past natural disturbance on the current spatial distribution of forest structural types.We found six forest structural types in the landscape: early regeneration(T1 and T2), young even-aged stands(T3), uneven-aged stands(T4) and adult stands(T5and T6).All of the types were related to the timing and severity of past storms, with early-regeneration structures being found in areas markedly affected in recent times, and adult stands predominating in those areas that had suffered lowest damage levels within the study period.In general, landscapes where high or medium levels of damage were recurrent also presented higher levels of spatial heterogeneity,whereas the opposite pattern was found in the less markedly affected landscape, characterized by thepresence of large regular patches.Our results show the critical role that storm regimes in terms of timing and severity of past storms can play in shaping current forest structure and future dynamics in subalpine forests.The knowledge gained could be used to help define alternative forest management strategies oriented toward the enhancement of landscape heterogeneity as a measure to face future environmental uncertainty. 展开更多
关键词 Storm regime Forest succession Forest structure Airborne Li DAR Spatial patterns Pyrenean Subalpine forests
下载PDF
ANALYSES OF INTRASEASONAL OSCILLATION CHARACTERISTICS OF FLOOD-CAUSING RAINSTORMS IN XIJIANG RIVER VALLEY DURING THE ANNUALLY FIRST RAINING SEASON IN THE PAST YEARS 被引量:1
6
作者 罗秋红 纪忠萍 +2 位作者 吴乃庚 蔡洁云 孙汉明 《Journal of Tropical Meteorology》 SCIE 2011年第2期136-146,共11页
Based on the daily precipitation data of nine stations representing the Xijiang River valley and the National Center for Environmental Prediction/National Center for Atmospheric Research (USA) reanalysis data, this st... Based on the daily precipitation data of nine stations representing the Xijiang River valley and the National Center for Environmental Prediction/National Center for Atmospheric Research (USA) reanalysis data, this study uses the wavelet analysis and band-pass filter methods to investigate the atmospheric intraseasonal oscillation characteristics of flood-causing rainstorms in the valley during the annually first raining seasons in 1968, 1994, 1998, 2002 and 2005. Results show that the daily precipitation in the valley exhibits significant quasi-biweekly (10 to 20 days) oscillations. The flood-causing rainstorms in the valley were mainly associated with the confluence of low-frequency warm and humid airflow in the lower latitudes and cold and dry airflow in the higher latitudes. The low-frequency vortexes were propagating or in control when this type of rainstorms took place over the valley, being favorable for the convergence of moisture at lower levels and thus vital to the formation of the rainstorms. 展开更多
关键词 rainstorms intraseasonal oscillation filter Xijiang River valley annually first raining season
下载PDF
Evaluation on the Thermal Stability and Hazards Behaviors of ADVN Using Green Thermal Analysis Approach
7
作者 Chi-Min Shu Yi-Hong Chang Chen-Wei Chiu 《Journal of Civil Engineering and Architecture》 2016年第3期280-290,共11页
ADVN (2,2'-Azobis (2,4-dimethyl) valeronitrile), a free radical initiator, is widely applied for the polymerization reaction of polymers in the chemical industries. When ADVN releases free radical during the deco... ADVN (2,2'-Azobis (2,4-dimethyl) valeronitrile), a free radical initiator, is widely applied for the polymerization reaction of polymers in the chemical industries. When ADVN releases free radical during the decomposition process, it can accompany abundant heat and huge pressure to increase the possibility of thermal runaway and hazard, causing unacceptable thermal explosion or fire accidents. To develop an inherently safer process for ADVN, the thermal stability parameters of ADVN were obtained to investigate thermal decomposition characteristics using a DSC (differential scanning calorimetry) and TG (thermogravimetry). We used various kinetic models to completely depict the kinetic behavior and determine the thermal safety parameters for ADVN. The green thermal analysis approach could be used to substitute for complicated procedures and large-scale experiments of traditional thermal analysis methods, avoiding environmental pollution and energy depletion. 展开更多
关键词 ADVN (2 2'-Azobis (2 4-dimethyl) valeronitrile) green thermal analysis approach kinetic models thermal runaway and hazard thermal safety parameters.
下载PDF
Characteristics of Clustering Debris Flows in Wenchuan Earthquake Zone 被引量:3
8
作者 MA Chao HU Kai-heng +1 位作者 ZOU Qiang TIAN Mi 《Journal of Mountain Science》 SCIE CSCD 2013年第6期953-961,共9页
Clustering debris-flow events, namely many debris flows simultaneously triggered by a regional rainstorm in a large-scale mountainous area,occurred in four regions of Wenchuan earthquake stricken areas in 2008 and 201... Clustering debris-flow events, namely many debris flows simultaneously triggered by a regional rainstorm in a large-scale mountainous area,occurred in four regions of Wenchuan earthquake stricken areas in 2008 and 2010. The characteristics of the clustering debris flows are examined with regard to triggering rainfall, formation process, and relationship with the earthquake by field survey and remote sensing interpretation. It is found that the clustering events occurred nearly at the same time with the local peak rainstorms, and the rainfall intensity-duration bottom limit line for clustering debris flows is higher than the worldwide line. It means that more rainfall is needed for the occurrence of the clustering debris flows. Four kinds of major formation processes for these debris flows are summarized: tributary-dominated, mainstreamdominated, transformation from slope failures, and mobilization or liquefaction of landslide. The four regions has a spatial correlation with the strongquake-influenced zone with the peak ground acceleration = 0.2 g and the seismic intensity > X. 展开更多
关键词 Clustering debris flows Wenchuanearthquake Rainfall threshold Formation process
下载PDF
Relationship between the Periodic Fluctuations of Pressure and Precipitation during a Rainstorm
9
作者 WU Li-Ji WEN Zhi-Ping HE Hai-Yan 《Atmospheric and Oceanic Science Letters》 CSCD 2015年第2期78-81,共4页
The relationship between periodic fluctuations of pressure and precipitation was investigated using the continuous wavelet transform and wavelet coherence transform methods for a rainstorm case that occurred during 19... The relationship between periodic fluctuations of pressure and precipitation was investigated using the continuous wavelet transform and wavelet coherence transform methods for a rainstorm case that occurred during 19–25 June 2005 in Guangdong Province, China. The results show that a period of 2–4 h existed in both pressure and precipitation fluctuations. Furthermore, this high frequency pressure fluctuation was closely related to the fluctuation of precipitation with a similar period, and the fluctuation of pressure was about two hours ahead of the precipitation fluctuation variation. Since the high frequency pressure fluctuation implies the existence of gravity wave activity, the results suggest that gravity wave activities with a 2–4 h period in the atmosphere exerted an important influence on precipitation during this rainstorm. 展开更多
关键词 heavy rainfall pressure fluctuation gravitywave
下载PDF
When Violence on Stage Becomes Real: My Name Is Rachel Corrie
10
作者 Susana Nicolas Roman 《Journal of Literature and Art Studies》 2011年第1期79-82,共4页
"Verbatim" is a kind of documentary theatre in which drama is made from the precise words spoken by people in evidence, witnessing or remembering. Raising political issues and controversial topics, My Name Is Rachel... "Verbatim" is a kind of documentary theatre in which drama is made from the precise words spoken by people in evidence, witnessing or remembering. Raising political issues and controversial topics, My Name Is Rachel Corrie (2005) is not just a moving play about violence in the Palestinian conflict. It is the real story of the murder of an American activist's fighting to denounce the genocide of innocent people. The problems of censorship that the play suffered in his premiere in New York remark the voice of a controversial play in Broadway's world. This paper will examine the images of violence present in the play and the value of the speaker as a real witness 展开更多
关键词 verbatim theatre VIOLENCE Israel-Palestinian conflict documentary theatre CENSORSHIP genocide
下载PDF
A Macaca mulatta model of fulminant hepatic failure 被引量:4
11
作者 Ping Zhou Jie Xia +6 位作者 Gang Guo Zi-Xing Huang Qiang Lu Li Li Hong-Xia Li Yu-Jun Shi Hong Bu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第5期435-444,共10页
AIM:To establish an appropriate primate model of fulminant hepatic failure (FHF).METHODS:We have,for the first time,established a large animal model of FHF in Macaca mulatta by intraperitoneal infusion of amatoxin and... AIM:To establish an appropriate primate model of fulminant hepatic failure (FHF).METHODS:We have,for the first time,established a large animal model of FHF in Macaca mulatta by intraperitoneal infusion of amatoxin and endotoxin.Clinical features,biochemical indexes,histopathology and iconography were examined to dynamically investigate the progress and outcome of the animal model.RESULTS:Our results showed that the enzymes and serum bilirubin were markedly increased and the enzyme-bilirubin segregation emerged 36 h after toxin administration.Coagulation activity was significantly decreased.Gradually deteriorated parenchymal abnormality was detected by magnetic resonance imaging (MRI) and ultrasonography at 48 h.The liver biopsy showed marked hepatocyte steatosis and massive parenchymal necrosis at 36 h and 49 h,respectively.The autopsy showed typical yellow atrophy of the liver.Hepatic encephalopathy of the models was also confirmed by hepatic coma,MRI and pathological changes of cerebral edema.The lethal effects of the extrahepatic organ dysfunction were ruled out by their biochemical indices,imaging and histopathology.CONCLUSION:We have established an appropriate large primate model of FHF,which is closely similar to clinic cases,and can be used for investigation of the mechanism of FHF and for evaluation of potential medical therapies. 展开更多
关键词 Fulminant hepatic failure Macaca mulatta BIOCHEMISTRY IMAGING PATHOLOGY
下载PDF
Wintertime Cyclone Activity and Its Relation to Precipitation over China 被引量:2
12
作者 CHEN Lei TAN Ben-Kui +1 位作者 Nils Gunnar KVAMSTΦ Ola M. JOHANNESSEN 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第5期387-393,共7页
The authors examined the variability in wintertime cyclone activity and storm tracks and their relation to precipitation over China for the period 1951-2006 using the observational data.Two apparent modes of variabili... The authors examined the variability in wintertime cyclone activity and storm tracks and their relation to precipitation over China for the period 1951-2006 using the observational data.Two apparent modes of variability were assumed for the cyclone activity and storm tracks.The first mode describes the oscillation in the strength of the storm tracks in East Asia,which significantly increased since the mid-1980s,whereas the second mode describes a seesaw oscillation in the storm track strength between the Central-Southeast China and northem East Asia.The storm tracks over the Central-Southeast China have increased since the late 1960s.The possible causes for the variation of the cyclone activity and storm tracks are also explored.It is shown that wintertime precipitation,which has increased since the mid-1980s,concentrates in Central-Southeast China.The enhancement may be caused by the first mode of variability of storm tracks,whereas the interannual variability of precipitation may be linked to the second mode of the storm track variability. 展开更多
关键词 CYCLONES PRECIPITATION winter East Asia monsoon
下载PDF
Tropical Cyclone Tilts Under Vertically Varying Background Flows:Preliminary Results Based upon TCM4 Simulations 被引量:1
13
作者 ZHENG Qikang LI Qingqing 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第5期1066-1074,共9页
The characteristics of tropical cyclone(TC) tilts under vertically varying background flows were preliminarily examined in this study based on numerical simulations with the Tropical Cyclone Model version 4(TCM4).The ... The characteristics of tropical cyclone(TC) tilts under vertically varying background flows were preliminarily examined in this study based on numerical simulations with the Tropical Cyclone Model version 4(TCM4).The tilt magnitudes presented a linearly decreasing tendency in the simulation with the environmental wind speed vertically varying throughout the troposphere and in the simulation with the vertical wind shear concentrated in the lower troposphere,while the vortex tilt showed a linearly increasing tendency in magnitude in the simulation where the vertical shear was concentrated in the upper troposphere.The change in tilt magnitude was found to be related to the evolution of the penetration depth near the eyewall.When the shear was concentrated in the lower troposphere,the vortex tended to tilt downshear right during the early integration and underwent more precession processes.When the shear was concentrated in the upper troposphere,the vortex rapidly tilted downshear left during the early simulation and vortex precession was less frequently observed.The storms simulated in all experiments were finally in downshear-left tilt equilibrium. 展开更多
关键词 tropical cyclone TILT vertical wind shear penetration depth
下载PDF
Full 2D Hydrodynamic Modelling of Rainfall-induced Flash Floods 被引量:6
14
作者 HUANG Wei CAO Zhi-xian +2 位作者 QI Wen-jun Gareth PENDER ZHAO Kai 《Journal of Mountain Science》 SCIE CSCD 2015年第5期1203-1218,共16页
Mountain catchments are prone to flash flooding due to heavy rainfall. Enhanced understanding of the generation and evolution processes of flash floods is essential for effective flood risk management. However, tradit... Mountain catchments are prone to flash flooding due to heavy rainfall. Enhanced understanding of the generation and evolution processes of flash floods is essential for effective flood risk management. However, traditional distributed hydrological models based on kinematic and diffusion wave approximations ignore certain physical mechanisms of flash floods and thus bear excessive uncertainty. Here a hydrodynamic model is presented for flash floods based on the full two-dimensional shallow water equations incorporating rainfall and infiltration. Laboratory experiments of overland flows were modelled to illustrate the capability of the model. Then the model was applied to resolve two observed flash floods of distinct magnitudes in the Lengkou catchment in Shanxi Province, China. The present model is shown to be able to reproduce the flood flows fairly well compared to the observed data. The spatial distribution of rainfall is shown to be crucial for the modelling of flash floods. Sensitivity analyses of the model parameters reveal that the stage and discharge hydrographs are more sensitive to the Manning roughness and initial water content in the catchment than to the Green-Ampt head. Most notably, as the flash flood augments due to heavier rainfall, the modelling results agree with observed data better, which clearly characterizes the paramount role of rainfall in dictating the floods. From practical perspectives, the proposed model is more appropriate for modelling large flash floods. 展开更多
关键词 Flash flood Full hydrodynamic model Spatial distribution RAINFALL
下载PDF
Storm in the Air: The Battle Over the 1992 Cable Act
15
作者 Samuel B. Hoff 《History Research》 2016年第3期121-133,共13页
Utilizing primary documents available at the George Bush Presidential Library, this study evaluates the veto record of President Bush using a case study as well as quantitative methods. The case study reviews the back... Utilizing primary documents available at the George Bush Presidential Library, this study evaluates the veto record of President Bush using a case study as well as quantitative methods. The case study reviews the background and fate of the only veto overridden during his term in office. It finds that the Bush White House had tried on several previous occasions to scrap the legislation, only to have it be reintroduced in each succeeding Congress. By 1992, when George Bush was running for reelection and in trouble politically, his team was unable to stave off defeat. The article likewise assesses the success of the Bush administration in its employment of the veto and compares the veto record of President Bush to previous and subsequent chief executives. 展开更多
关键词 VETO override PRESIDENT CONGRESS cable regulation 1992 Cable Act
下载PDF
The Scenes of the Obscene in Contemporary Turkish Art
16
作者 Elif Cimen 《Journal of Literature and Art Studies》 2014年第6期475-482,共8页
In contemporary Turkish art, topics or items considered obscene by society are being carried out by a number of artists with protest, agitation, anti-propaganda, or strike purposes. Issues that are often seen in socia... In contemporary Turkish art, topics or items considered obscene by society are being carried out by a number of artists with protest, agitation, anti-propaganda, or strike purposes. Issues that are often seen in social life such as domestic violence, honour killings, rape, gender discrimination, intolerance against minority groups generate some artists' main theme in their work. Certain circles do not show any reaction to such social wounds, or even support. These circles that have no discomfort in the existence of these wounds get disturbed when they face these social realities through artistic activities. These artists are subject to threats or even physical attacks by such groups. In this paper, Turkish artists, namely Sukran Moral, Taner Ceylan, and Nezaket Ekici who make use of such obscene scenes in their works, will be analyzed including their performances, reactions, and attitudes toward threats and attacks. 展开更多
关键词 obscenity in art obscene Turkish art contemporary art
下载PDF
Case study of ionospheric fluctuation over mid-latitude region during one large magnetic storm 被引量:10
17
作者 ZHANG DongHe MO XiaoHua +1 位作者 A Ercha HAO YongQiang 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第5期1198-1206,共9页
From Nov. 6 to 10, 2004, a large number of solar events occurred, which triggered many solar flares and coronal mass ejections (CMEs). These CMEs caused two large geomagnetic storms and continuous energy proton events... From Nov. 6 to 10, 2004, a large number of solar events occurred, which triggered many solar flares and coronal mass ejections (CMEs). These CMEs caused two large geomagnetic storms and continuous energy proton events. During this period, one large positive ionospheric storm happened over the East-Asian region on Nov. 8, 2004. On Nov. 10, 2004, a strong spread-F was observed by the ionosonde located in the mid-latitude region of East China and Japan, and the ionospheric fluctuation over the ionosonde stations derived from GPS observation was also obvious. In this report, the characteristics of the spatial distribution of the ionosphere fluctuation and its temporal evolution are studied using the parameter of the rate of total electron content (ROT) derived from dual-frequency GPS measurement. Strong fluctuating activity of the ionosphere was found over the mid-latitude region in the southern and northern hemispheres between longitudes of 100°E and 180°E during the magnetic storm period on Nov. 10, 2004, and a regular movement of the disturbing region was observed. In the end, the reason of the ionospheric fluctuation during this magnetic storm is analyzed. 展开更多
关键词 ionospheric irregularities ionospheric scintillation TEC GPS rate of TEC
原文传递
Investigation on very large scale motions(VLSMs) and their influence in a dust storm 被引量:9
18
作者 ZHENG XiaoJing ZHANG JingHong +2 位作者 WANG GuoHua LIU HongYou ZHU Wei 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第2期306-314,共9页
Based on the real-time synchronous measurements of the wind velocity,temperature,the PM10 concentration at 16 m and 47 m during a dust storm event,in which Reynolds number Re exceeds 6×106,this study reveals the ... Based on the real-time synchronous measurements of the wind velocity,temperature,the PM10 concentration at 16 m and 47 m during a dust storm event,in which Reynolds number Re exceeds 6×106,this study reveals the existence of the very large scale motions(VLSMs) during the stable stage both in the stream velocity and the temperature field at the two heights,whose streamwise scales reach up to 10 times the thickness of the boundary layer.The streamwise velocity and the PM10 concentration display a similar frequency corresponding to the peaks of their energy spectra,which implies that the VLSMs of streamwise flow have a significant role in dust transportation.In contrast,the salient deviations of the PM10 concentration at 47 m from the Gaussian distribution are revealed,which means that 47 m is not in the dust transportation layer,but is a region where the dust transportation layer and the outer flow intersect each other.Analysis demonstrates that the energy spectra of the PM10 concentrations at 16 m and 47 m display the "-1" scaling law feature,which has the same frequency range(0.001-0.1 Hz) as that of the wind velocity.This provides a new paradigm for the existence of the self-similarity scaling region in turbulent flow. 展开更多
关键词 high-Reynolds turbulence dust storm very large scale motions power spectrum field observation
原文传递
Large-eddy-simulation of 3-dimensional Rayleigh-Taylor instability in incompressible fluids 被引量:1
19
作者 王丽丽 李家春 谢正桐 《Science China Mathematics》 SCIE 2002年第1期95-106,共12页
The 3-dimensional incompressible Rayleigh-Taylor instability is numerically studied through the large-eddy-simulation ( LES) approach based on the passive scalar transport model. Both the instantaneous velocity and th... The 3-dimensional incompressible Rayleigh-Taylor instability is numerically studied through the large-eddy-simulation ( LES) approach based on the passive scalar transport model. Both the instantaneous velocity and the passive scalar fields excited by sinusoidal perturbation and random perturbation are simulated. A full treatment of the whole evolution process of the instability is addressed. To verify the reliability of the LES code, the averaged turbulent energy as well as the flux of passive scalar are calculated at both the resolved scale and the subgrid scale. Our results show good agreement with the experimental and other numerical work. The LES method has proved to be an effective approach to the Rayleigh-Taylor instability. 展开更多
关键词 Rayleigh-Taylor instability LARGE-EDDY-SIMULATION passive scalar turbulent mixing
原文传递
Tropical storm-forced near-inertial energy dissipation in the southeast continental shelf region of Hainan Island 被引量:5
20
作者 ZHANG ShuWen XIE LingLing +1 位作者 ZHAO Hui HOU YiJun 《Science China Earth Sciences》 SCIE EI CAS 2014年第8期1879-1884,共6页
Near-inertial motion is an important dynamic process in the upper ocean and plays a significant role in mass, heat, and energy transport across the thermocline. In this study, the dissipation of wind-induced near-iner... Near-inertial motion is an important dynamic process in the upper ocean and plays a significant role in mass, heat, and energy transport across the thermocline. In this study, the dissipation of wind-induced near-inertial energy in the thermocline is investigated by using observation data collected in July and August 2005 during the tropical storm Washi by a moored system at(19°35′N, 112°E) in the continental shelf region off Hainan Island. In the observation period, the near-inertial part dominated the observed ocean kinetic energy and about 80% of the near-inertial energy dissipated in the upper layer. Extremely strong turbulent mixing induced by near-inertial wave was observed in the thermocline, where the turbulent energy dissipation rate increased by two orders of magnitude above the background level. It is found that the energy loss of near-inertial waves in the thermocline is mainly in the large-scales. This is different from the previous hypothesis based on "Kolmogorov cascade" turbulence theory that the kinetic energy is dissipated mainly by small-scale motions. 展开更多
关键词 tropical storm Washi continental shelf region of Hainan Island near-inertial energy dissipation in thermocline
原文传递
上一页 1 2 下一页 到第
使用帮助 返回顶部