高纬电离层中非麦克斯韦分布等离子体的非相干散射谱的模拟

使用一个修正的双麦克斯韦分布函数，通过最小均方适应技术使它与高纬电离层Ｆ区中离子的非麦克斯韦速度分布函数相适配．结果表明，使用这样的分布函数可以简化非相干散射谱的计算，并有助于简化高纬地区电离层非相干散射谱的反演．     

不同地震序列类型的早期特征

本文研究了不同地地震列类型的早期特征。得到了利用地震序列第一天特征来判别地震类型的两个指标：地震频度Ｎ和震级级差△Ｍ。研究结果表明，这两项指标简单明了，使用方便，且具有较好的判别效果，对地震现场工作具有一定的意义。     

具有非合作连边的一般线性多智能体系统包含控制研究

本文研究了通信拓扑中具有非合作连边的一般线性多智能体系统的包含控制问题.系统中允许多个领导者的存在,这些领导者的状态可以通过它们与邻居领导者进行交互而动态地变化.采用最近邻居规则设计分布式控制协议,利用线性矩阵不等式技术和线性系统控制理论证明了跟随者的状态轨迹最终收敛到由领导者的状态轨迹及领导者相反轨迹生成的凸包中,成功解决了符号图上线性多智能体系统的包含控制问题.仿真结果验证了结论的正确性.     

Extended Impact of Cold Air Invasions in East Asia in Response to a Warm South China Sea and Philippine Sea

During boreal winter, the invasion of cold air can lead to remarkable temperature drops in East Asia which can result in serious socioeconomic impacts. Here, we find that the intensity of strong synoptic cold days in the East China Sea and Indochina Peninsula are increasing. The enhanced synoptic cold days in these two regions are attributed to surface warming over the South China Sea and Philippine Sea(SCSPS). The oceanic forcing of the SCSPS on the synoptic cold days in the two regions is veri...     

华南冬末春初降水变异关联主模态及机理

基于1951—2018年再分析资料和观测的降水量资料,采用联合经验正交函数分解的方法,分析了华南冬末春初(2、3月)降水年际变异特征,并讨论了相应的环流背景及物理机制。华南2、3月降水变异的第一关联主模态反映出全区2、3月同相变化,第二模态呈现反相变化。第一模态的降水异常与ENSO关联的热带海温异常分布有关,其导致的西太平洋异常反气旋的维持使得2、3月的降水持续出现同相异常。第二模态的降水异常与中高纬度的大气环流异常有关：2月表现为欧亚遥相关型,3月则表现为北极涛动型。第二模态2、3月位势高度异常型的转变分别与北大西洋的热通量的异常变化及平流层极涡信号的下传有关：当2月北大西洋热通量正异常显著时,500 hPa高度场呈现欧亚遥相关(EU)负位相的分布;平流层极涡异常信号在3月下传达到对流层低层,使得3月对流层极涡增强,有利于北极涛动(AO)正位相的形成。2、3月欧亚大陆上空分别在EU遥相关型和AO型环流异常的影响下,导致了华南地区上空的大气环流的辐合辐散异常,并最终造成2、3月华南的降水量反相异常的出现。     

江西德兴雷高雾金矿矿床成因及成矿阶段

金矿床赋存于金山矿田东侧中元古界浅变质岩系中,受韧性剪切带控制的变质热液型金矿,双桥群的浅变质岩系为矿源层。矿床经历区域变质成矿期和动力变质成矿期两个成矿阶段,浅变质岩系和北东向韧性剪切带是最主要的找矿标志。     

Flood simulation in the coastal lowlands of northern Jiangsu,China

The coastal lowlands in northern Jiangsu Province, China, is characterized by low relief and low water surface gradient in streams. The flooding stages are commonly lower than the high-tide level and the tidal range is relatively small. All these factors prohibit rapid discharge of floodwater and make the flood regimes here extremely sensitive to the sea level rise. The 1991 Plum Rain was examined, when precipitation was significantly higher than normal. The one-dimensional open-channel non-conservative flow model was used to simulate the stream flow in the channel network of studied area. GIS technology was used to delineate the maximum in undated area by analyzing the DEMs.     

An instructural system model of coastal management to the water related hazards in China

Coastal lowlands have large areas of hazard impact and relatively low capacity of prevention to the water related hazards, which have been indicated by the wide-spread flood hazards, high percentages of land with high flood vulnerability. Increasing propulation pressure and the shift of resources exploitation from land to sea will force more and more coastal lowlands to be developed in the future, further enhancing the danger of water-related hazards. In this paper, the coastal lowlands in the northern Jiangsu province, China, were selected as a case study. The Interpretation Structural Model (ISM) was employed to analyze the direct and indirect impacts among the elements within the system, and thereby, to identify the causal elements, middle linkages, their expression, and relations.     

Effects of vegetation cover on summer climate in China during 1982–2001

In this paper, we apply lagged correlation analysis to study the effects of vegetation cover on the summer climate in different zones of China, using NOAA/AVHRR normalized difference vegetation index (NDVI) data during the time period from 1982 to 2001 and climate data of 365 meteorological stations across China (precipitation from 1982 to 2001 and temperature from 1982 to 1998). The results show that there are positive correlations between spring NDVI and summer climate (temperature and precipitation) in most zones of China; these suggest that, when the vegetation cover increases, the summer precipitation will increase, and the lagged correlations show a significant difference between zones. The stronger correlations between NDVI in previous season and summer climate occur in three zones (Mid-temperate zone, Warm-temperate zone and Plateau climate zone), and this implies that vegetation changes have more sensitive feedback effects on climate in the three zones in China.     

冻藏龙眼果皮细胞膜透性、PPO活性和酚类物质含量的变化

将“油谭本”龙眼在 - 40℃条件下进行速冻 ,然后转入 - 18℃恒定低温冷库中冻藏 180d。测定了龙眼果实速冻时的冻结曲线、冻藏过程中果皮细胞膜渗透率、果皮内PPO的活性和总酚含量的变化情况。试验结果表明 ,- 40℃的冷冻温度即可满足速冻要求 ;冻藏可以有效地抑制果皮内PPO的活性 ,果皮细胞膜渗透率和总酚含量的变化较小 ,能够较好地保持果实的外观品质。