2005年川西"7.3"暴雨多普勒雷达回波个例分析

利用多普勒雷达的基本反射率图、径向速度图及相关资料,分析了7.3四川西部区域性暴雨天气过程,发现:就基本反射率而言,多普勒雷达与713数字化雷达所监测到的川西暴雨回波演变规律一致;径向速度图上,强降水区域存在明显的风向、风速的切变.     

大力提升工程设计企业的技术创新能力

设计是整个工程的灵魂,是科技成果转化为现实生产力的桥梁和杠杆,技术创新是带动工程建设技术进步的先导.工程设计企业要紧跟世界科技发展的步伐,在技术创新中追求可持续发展.转变观念是提升技术创新能力的先导,加大投入是提高创新能力的基础,人才资源是提高技术创新能力的核心,技术创新是企业增强核心竞争力的根本途径.     

星地时间比对的原理及实现

文章介绍了几种星地时间比对的方法并对几种方法的精度进行了简要分析。为验证分析的正确性，文章首先采用2002年10月GPS35卫星的伪距和SLR实测数据计算了星地钟差，然后将本文计算的星地钟差与IGS精密星地钟差进行了比较。通过比较分析发现：①利用伪距与卫星激光测距比对计算的星地钟差精度可以达到1．5ns；测定的星地钟差与实际的星地钟差不存在系统差。②利用伪距与卫星激光测距比对可以完成导航卫星钟与地面系统标准时钟的比对；该方法有助于分离导航卫星的坐标和钟差，便于对星地钟差的研究。     

The Thickness of Seismogenic Layer Under the Areas Surrounding the Ordos Block, Northern China

—?A seismic approach was used to calculate the thickness distribution of the seismogenic layer under the block Ordos in northern China. This block was chosen because of its stability, the complicated tectonics around its boundaries and the completeness of the data set. Several strong earthquakes occurred in this area in the 20^th century, with the largest one (Haiyuan, M= 8.4, 1920) in the southwest of the Ordos. Most of the large faults around the Ordos are strike-slip ones. The breaking point (i.e., the saturation of earthquake magnitudes M ^c ) of the self-similarity from small to large events based on the Gutenberg-Richter relation is calculated. Under the assumption of the L model which expresses that the offset is proportional to the length of the fault (Scholz, 1982, 1990, 1994), the thickness (W _c ) of the seismogenic layer is directly related to M ^c . To display smoothly the change of the thickness of the seismogenic layer and to ensure the reliability of the results, a moving cell of 150 events, with a moving step of 0.1 degree, was adopted. To take advantage of the existing data set, the “mean value method,” which is based on the latest complete data information to make the existing data set a `complete' one, was used to extrapolate it so that the data covers the whole time period. The results show that the average thickness of the seismogenic layer in the southwest, in the northwest and in the east of the Ordos is around 30, 9 and 17?km, respectively. The thickness generally decreases from the southwest to the northeast. This kind of spatial variation is in agreement with the maximum depth distribution of large amounts of microearthquakes, with the correlation coefficient to be about 0.88, and the Moho depth.     

西部地震资料主要处理技术研究

西部地区地表情况多样,资料品质较差,多属低信噪比资料。这对类资料,静校正叠前去噪及速度分析等技术是非常重要的基础工作。针对西部地区不同的资料采用相应的静校正方式,在叠前去噪方面,就FK域倾角滤波方法的应用上进行了改进,克服了该方法一些“蚯蚓化”、“假构造”等弊端,总结出一套切实可行的尤其是用于西部资料的去噪方法。并针对多次波的特点,采用时间域,频率域及τp域等多种方式进行多次压制,在西部资料的处理中取得了较好的效果。     

用年雨量和11月份气温作融安县倒春寒预报

用年雨量和１１月份气温作融安县倒春寒预报覃克星（融安县气象局５４５４００）１倒春寒预报指标融安属桂北山区,倒春寒是以３月２０日以后出现日平均气温≤１２．０℃且连续３ｄ或以上称为有倒春寒,反之为无倒春寒。经过分析,得出：融安降雨量偏少（即年雨量在１６０...     

强震概率增长时段判定法在粤东及邻区的应用

将强震概率增长时段判定法（ＴＩＰ－Ｍ８）应用于粤、闽、赣交界及近海地区,资料从１９８５至１９９５年底。绝大多数地震流函数异常显示,从１９９５年底起３年内该区将发生５．５级左右地震。１９９７年５月３１日发生的福建永安５．２级地震与此判断相符。     

螺旋CT的临床应用

探讨螺旋ＣＴ在临床应用价值,选择部分典型病例３０例,其中血客性病变或螺及血管的病变８例,骨病变２１例,胆道病变１例,扫描机为Ｐｈｉｌｉｐａ Ｔｏｍｏｓｃａｎ Ａｖｅｐ。血管成像为主的,选择２－５ｍｍ的准直器宽度和床速,１２ｍｍ间隔重建,其它病变选择５－７ｍｍ的准直器宽度和床速,２－３ｍｍ间隔重建,增强扫描使用６０％的碘造影剂８０－１２０ｍｌ,以脏静脑用高压注射器注入,速率３ｍｌ／ｓ,脑血管和腹腔建     

Pollen-based reconstruction of vegetation patterns of China in mid-Holocene

Biomization provides an important way to assign pollen taxa to biomes and to simulate palaeo-vegetation patterns, so that pollen data can be mapped to reconstruct biogeography and climate. The authors have tested the applicability of this procedure to assign modern pollen surface samples from China to biomes. The procedure successfully delineated the major vegetation types of China. When the same procedure was applied to 6 ka B. P. fossil pollen samples, the reconstructions showed that the forest zones were systematically shifted northwards ca. 300–500 km beyond their present northern limits in eastern China; the area of desert and steppe vegetation was reduced compared to the present in northwestern China; the area of tundra was reduced largely on the Tibetan Plateau. This research is a contribution to the project of BIOME 6000 in Pacific-Asian regions. Project supported by the Funding for Returned Students from the Overseas of the State Education Commission of China, the Postdoctoral Station, and State Pilot Laboratory of Coast & Island Development of Nanjing University, Financial support has also been provided by European Community (EV5V-CT95-0075) and by the Swedish Natural Science Research Council (G-AA/GU 09334-321).     

NUMERICAL STUDY ON THE EFFECTS OF SEA SURFACE TEMPERATURE ON TROPICAL CYCLONE INTENSITY-PART I:NUMERICAL EXPERIMENT OF THE TROPICAL CYCLONE INTENSITY RELATED TO SST *

In the context of a model of tropical cyclone intensity based on an improved meso-scale atmospheric model, numerical simulation is performed of the track and intensity variation of tropical cyclones(TC) arising from sea surface temperature(SST) variation over a specified sea region. Evidence suggests that the model is capable of modeling quite welt the track and intensity of TC:SST variation leads to an abrupt change in the cyclone intensity:the response of the cyclone to the abrupt SST change lasts 8-12 h.