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The characteristic differences of tropical cyclones forming over the western North Pacific and the South China Sea

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Acta Oceanologica Sinica 2007年第4期26卷 29-43页

作者： YUAN Jinnan WANG Dongxiao LIU Chunxia huang Jian huang huijun Key Open Laboratory for Tropical Monsoon Guangzhou Institute of Tropical and Marine Meteorology China Meteorological Administration Guangzhou 510080 China Laboratory for Tropical Marine Environmental Dynamics South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

The best track dataset of tropical cyclones in the western North Pacific （WNP） and the South China Sea （SCS） from 1977 to 2005 during the satellite era, the NCEP/NCAR reanalysis dataset and the extended reconstructed sea surface temperature dataset are employed in this study. The main climatological characteristics of tropical cyclone formation over the WNP and the SCS are compared. It is found that there is obviously different for the locations of tropical cyclone origins, achieving the lowest central pressure and termination points between over the WNP and over the SCS. The annual number of tropical cyclones forming over the SCS is obviously less than over the WNP, and there is a significant negative correlation with the correlation coefficient being - 0.36 at the 5% significance level between over the WNP and over the SCS. The mean speed of tropical cyclone moving is 6.5 m/s over the WNP and 4.6 m/s over the SCS. The mean lowest central pressure of tropical cyclones is obviously weaker over the SCS than over the WNP. The tropical cyclone days per year, mean total distance and total displacement of tropical cyclone traveled over the WNP are all obviously longer than those over the SCS. Tropical cyclone may intensify to Saffir - Simpson hurricane scale 5 over the WNP, but no tropical cyclone can intensify to Saffir - Simpson hurricane scale 3 over the SCS. The changing ranges of the radii （R15,R16） of the 15.4 m/s winds them and the 25.7 m/s winds over the WNP are obviously wider than those over the SCS, and the median values of the radii over the WNP are also larger than those over the SCS. For the same intensity of tropical cyclones, both radii have larger medians over the WNP than over the SCS. The correlations of annual mean tropical cyclone size parameters between over the WNP and over the SCS are not significant. At the same time, the asymmetric radii of tropical cyclones over the WNP are different from those over the SCS.

关键词： characteristic differences tropical cyclone western North Pacific and South China Sea

Evaluation of the Global and Regional Assimilation and Prediction System for Predicting Sea Fog over the South China Sea

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Advances in Atmospheric Sciences 2019年第6期36卷 623-642页

作者： huijun huang Bin huang Li YI Chunxia LIU Jing TU Guanhuan WEN Weikang MAO Institute of Tropical and Marine Meteorology China Meteorological Administration National Meteorological Centre Ocean University of China Guangdong Meteorological Observatory

In the South China Sea, sea fog brings severe disasters every year, but forecasters have yet to implement an effective seafog forecast. To address this issue, we test a liquid-water-content-only(LWC-only) operational sea-fog prediction method based on a regional mesoscale numerical model with a horizontal resolution of about 3 km, the Global and Regional Assimilation and Prediction System(GRAPES), hereafter GRAPES-3 km. GRAPES-3 km models the LWC over the sea, from which we infer the visibility that is then used to identify fog. We test the GRAPES-3 km here against measurements in 2016 and 2017 from coastal-station observations, as well as from buoy data, data from the Integrated Observation Platform for Marine Meteorology, and retrieved fog and cloud patterns from Himawari-8 satellite data. For two cases that we examine in detail, the forecast region of sea fog overlaps well with the multi-observational data within 72 h. Considering forecasting for0–24 h, GRAPES-3 km has a 2-year-average equitable threat score(ETS) of 0.20 and a Heidke skill score(HSS) of 0.335,which is about 5.6%(ETS) and 6.4%(HSS) better than our previous method(GRAPES-MOS). Moreover, the stations near the particularly foggy region around the Leizhou Peninsula have relatively high forecast scores compared to other sea ***, the results show that GRAPES-3 km can roughly predict the formation, evolution, and dissipation of sea fog on the southern China coast.

关键词： sea fog operational GRAPES model southern China coast forecast evaluation

The characteristics of sea fog with different airflow over the huanghai Sea in boreal spring

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Acta Oceanologica Sinica 2010年第4期29卷 3-12页

作者： huang Jian WANG Xin ZHOU Wen huang huijun WANG Dongxiao ZHOU Faxiu Institute of Tropical and Marine Meteorology China Meteorological Administration Guangzhou 510080 China Guy Carpenter Asia-Pacific Climate Impact Centre School of Energy and Environment City University of Hong Kong Hong Kong China CAS key laboratory of tropical marine environmental dynamics South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China Department of meteorology Ocean University of China Qingdao 262003 China

Using the observations from ICOADS datasets and contemporaneous NCEP/NCAR reanalysis datasets during 1960-2002,the study classifies the airflows in favor of sea fog over the huanghai （Yellow） Sea in boreal spring （April-May） with the method of trajectory analysis,and analyzes the changes of proportions of warm and cold sea fogs along different paths of *** to the heat balance equation,we investigate the relationships between the marine meteorological conditions and the proportion of warm and cold sea fog along different airflow *** major results are summarized as follows.（1） Sea fogs over the huanghai Sea in spring are not only warm fog but also cold *** proportion of warm fog only accounts for 44% in April,while increases as high as 57% in May.（2） Four primary airflow paths leading to spring sea fog are *** are originated from the northwest,east,southeast and southwest of the huanghai Sea,*** occurrence ratios of the warm sea fog along the east and southeast airflow paths are high of 55% and 70%,while these along the southwest and northwest airflow paths are merely 17.9% and 50%.（3） The key physical processes governing the warm/cold sea fog are heat advection transport,longwave radiation cooling at fog top,solar shortwave warming and latent heat flux between airsea interfaces.（4） The characteristics of sea fog along the four airflow paths relate closely to the conditions of water vapor advection,and the vertical distribution of relative humidity.

关键词： spring sea fog over the huanghai Sea airflow paths water vapor flux heat advection vertical distribution of water vapor

不同波系配置的鼓包压缩面引起的激波/边界层干扰特性

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航空动力学报 2018年第2期33卷 372-382页

作者：王娇谭慧俊黄河峡南京航空航天大学能源与动力学院江苏省航空动力系统重点实验室南京210016

为了对不同波系配置的鼓包压缩面引起的锥形激波和来流边界层干扰的流场特性进行对比分析,分别以总偏转角相同的单锥、双锥和等熵锥等3种外锥流场为基准流场,在来流马赫数为2.0的条件下,采用流线追踪法设计了3种鼓包压缩面。在此基础上... 详细信息

为了对不同波系配置的鼓包压缩面引起的锥形激波和来流边界层干扰的流场特性进行对比分析,分别以总偏转角相同的单锥、双锥和等熵锥等3种外锥流场为基准流场,在来流马赫数为2.0的条件下,采用流线追踪法设计了3种鼓包压缩面。在此基础上,采用数值仿真的方法对这3种鼓包压缩面在不同马赫数下的三维激波/边界层干扰流场进行了对比分析,结果表明:相比于单锥鼓包,双锥和等熵鼓包流场中的涡量集中区明显减小,且涡核处的涡量值也有所降低;对于双锥和等熵鼓包,由于受到后续波系的干扰,其表面流动的拓扑结构不再呈现出锥形相似性;双锥与等熵鼓包具有和单锥鼓包相同的边界层排移能力,且这一能力不随来流马赫数的变化而变化。此外,采用多波系配置能提高鼓包外压缩系统的总压恢复系数,波系数目越多,提升的程度就越大,且这一优势在高马赫数下更加明显。

关键词： Bump进气道激波/边界层干扰波系配置边界层排移能力总压恢复系数

Bump进气道中鼓包诱导的激波/边界层干扰特性

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航空动力学报 2018年第1期33卷 97-107页

作者：王娇谭慧俊黄河峡南京航空航天大学能源与动力学院江苏省航空动力系统重点实验室南京210016

为了探索Bump进气道中鼓包诱导的锥形激波和机身发展而来的湍流边界层干扰问题,分析其气动优势,首先选取了半锥和半棱锥这两种与鼓包的流场结构具有一定相似性的构型作为参照,采用数值仿真方法,分别对这三类典型的三维激波/湍流边界层... 详细信息

为了探索Bump进气道中鼓包诱导的锥形激波和机身发展而来的湍流边界层干扰问题,分析其气动优势,首先选取了半锥和半棱锥这两种与鼓包的流场结构具有一定相似性的构型作为参照,采用数值仿真方法,分别对这三类典型的三维激波/湍流边界层干扰问题进行了流场分析。在此基础之上,设计了三个不同马赫数的鼓包,并研究了设计马赫数对鼓包流场特性的影响。结果表明:当三类构型的无黏激波强度相等时,半锥诱导产生的旋涡强度最强,鼓包次之,半棱锥最弱。尽管鼓包诱导的流场非常复杂,其干扰流场却呈现出准锥形相似的特性。虽然半锥对边界层的排移能力最强,但是综合考虑边界层排移能力及进气道出口流场畸变下,鼓包最具优势,这也是其被选为超声速进气道前缘压缩面的重要原因之一。此外,在设计状态下,适当增加设计马赫数能改善鼓包排移边界层的能力,但设计马赫数太高,边界层排移能力基本不变,反而使得进气道总压损失急剧增加。

关键词： Bump进气道激波/边界层干扰旋涡结构准锥形准则边界层排移能力

A blast-resistant and high-yielding rice variety Shuangchao 25

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Chinese Rice Research Newsletter 1991年第3期 1-2页

作者： huang huijun Liu Lixian ZHANG Junying ZHOU Hanqin huang Yaoxiang Rice Research Institute,Guangdong Academy of Agricultural Sciences (GAAS),Guangzhou 510640,China

Shuangchao 25 was derived from the cross ofShuanggui 36/Kang 2 in *** female parentwas a panicle-number type with quick growth andstrong-tiUering *** male parent was apanicle-weight type with Bl and BB *** segregated ... 详细信息

关键词： high A blast-resistant and high-yielding rice variety Shuangchao 25

A blast-resistant and high-yielding rice variety Shuangchao 25

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Rice Science 1991年第4期 1-2页

作者： huang huijun Liu Lixian ZHANG Junying ZHOU Hanqin huang Yaoxiang Rice Research Institute,Guangdong Academy of Agricultural Sciences (GAAS),Guangzhou 510640,China

关键词： high A blast-resistant and high-yielding rice variety Shuangchao 25

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闭环供应链MIS系统规划研究

科技管理研究 2011年第5期31卷 198-201页

作者：黄慧君杜兰南京理工大学经济管理学院江苏南京210094

运用系统论和信息系统规划的原理和方法理论,在闭环供应链管理特点和数据流程的基础上,进行闭环供应链MIS系统综合设计,给出了系统总体结构设计和关键功能模块分析。最后结合汽车行业闭环供应链特点,建立一种基于汽车产品生命周期的汽... 详细信息

运用系统论和信息系统规划的原理和方法理论,在闭环供应链管理特点和数据流程的基础上,进行闭环供应链MIS系统综合设计,给出了系统总体结构设计和关键功能模块分析。最后结合汽车行业闭环供应链特点,建立一种基于汽车产品生命周期的汽车行业闭环供应链管理信息系统的三层结构模型,即模型支撑层、系统执行层和汽车生命周期主线层,期望对汽车行业实施闭环供应链管理信息系统进行一些有益的探索,为其他行业提供参考。

关键词：闭环供应链管理信息系统汽车行业

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粒子束空间传输影响因素及应对方法

国防科技大学学报 2023年第2期45卷 138-145页

作者：任三孩邢艳军彭忠黄惠军北京跟踪与通信技术研究所北京100094 北京空间飞行器总体设计部北京100094 北京卫星环境工程研究所北京100094 西安空间无线电技术研究所陕西西安710100

全面分析了初始束流分布、发散度、能散度以及地磁场对粒子束空间传输的影响情况,并针对束流长距离传输的静电扩散和地磁偏转效应进行了数值建模及定量的数值仿真研究。结果表明,对于固定束流能量、流强粒子束,可通过增大初始半径削弱... 详细信息

全面分析了初始束流分布、发散度、能散度以及地磁场对粒子束空间传输的影响情况,并针对束流长距离传输的静电扩散和地磁偏转效应进行了数值建模及定量的数值仿真研究。结果表明,对于固定束流能量、流强粒子束,可通过增大初始半径削弱粒子束静电扩散效应达到设计要求;通过背景磁场精确预测,可准确控制束流方向精度。可以看出,研究带电粒子束本身的自洽行为以及与外场的作用,对带电粒子束流的产生、传输特性研究及工程化应用都有重要意义。

关键词：粒子束空间传输静电扩散地磁偏转