中国分县生态承载力供需平衡空间格局分析(英文)

A balanced ecological carrying capacity and its understanding are important to achieve sustainable development for human kind.Here,the concept of ecological carrying capacity has been used for measuring the dependencies between human and nature.China’s ecological balance between supply and demand has become a global concern and is widely debated.In this study the ’Ecological Footprint’ method was used to analyze the supply-demand balance of China’s ecological carrying capacity.Firstly,the ecological supply and demand balance was calculated and evaluated,and secondly,the ecological carrying capacity index (ECCI) was derived for each county of China in 2007,and finally this paper systematically evaluated the ecological carrying capacity supply-demand balance of China.The results showed that ecological deficit appeared to be the main characteristic of ecological carrying capacity supply-demand balance in 2007 of China at county scale.In general,more than four-fifths of the Chinese population was concentrated in less than one-third of the land area and more than two-thirds of the land area was inhabited by less than one-fifth of the population.The spatial distribution of the ecological carrying capacity demand-supply was unbalanced ranging from significant overloading to affluence from southeastern to northwestern part of China.It appeared to be more dominant in regions located at coastal areas which are attracted by migrants and had a generally higher population density.Along with the rapid development and urbanization trends in China,ecological deficits in these regions will become more severe.     

新一代天气雷达负仰角探测能力分析

由于地球曲率的影响,当CINRAD.SA新一代天气雷达使用目前最低仰角同定为0.5°的模式探测时,探测肓区较大,对低层降水回波的探测能力严重不足.在实地展开试验的基础上,推导了负仰角探测时雷达最低探测高度计算公式,计算出仰角为0.5°、0°、-0.3°、-0.5°时不同探测距离上的雷达最低探测高度,对比分析不同仰角观测模式的主要雷达产品特点,探讨新一代天气雷达使用负仰角观测模式的局限性,提出了新一代天气雷达使用负仰角观测的建议.     

基于贝叶斯模型平均的全球洪水中长期预报评估研究

筛选全球5839个水文站逐日径流数据,采用超阈值采样法提取洪水发生频率及时间,将各季节最大日流量作为季节洪水量级,以优选的多个大尺度气候因子的最佳前置月份序列作为潜在预报因子,基于贝叶斯模型平均法构建全球尺度洪水中长期预报模型,并利用均方误差技术指数（MSESS）评价模型的预报效果。结果表明：全球范围内,洪水量级和频率模拟预报效果合格（0.6>MSESS>0.2）的水文站点占比分别为48%和28%;利用前置季节气候因子数据,驱动所构建的洪水中长期预报模型,有效预报了2020年鄱阳湖流域洪水量级将异常偏高。     

Hollow Cylinder Simulation Experiments of Galleries in Boom Clay Formation

In the context of nuclear waste disposal in clay formations, laboratory experiments were performed to study at reduced scale the excavation damaged zone (EDZ) induced by the construction of galleries in the Boom clay formation. For this purpose, thick-walled hollow cylindrical samples were subjected (after recovery of in situ stress conditions) to a decrease in the inner confining pressure aiming at mimicking a gallery excavation. X-ray computed tomography (XRCT) scans of the specimens were carried out through the testing cell before and after the mechanical unloading and allowed to quantify the displacements undergone by the clay as a result of the mechanical unloading. The deformation of the hollow cylinders and the inferred extent of the damaged zone around the central hole are found to depend on the orientation of the specimen with respect to the bedding planes and show a great similarity with in situ observations around galleries and boreholes at Mol URL in the Boom clay formation. In the experiments performed on samples cored parallel to the bedding, the damaged zone is not symmetrical with respect to the hole axis and extends more in the direction parallel to the bedding. It is the same for the radial convergence of the hole walls which is larger in the direction parallel to bedding than in the perpendicular one. In contrast, a test on a sample cored perpendicularly to the bedding did not show any ovalisation of the central hole after the mechanical unloading. These observations confirm the significance of the pre-existing planes of weakness (bedding planes) in Boom clay and the need for a correct consideration of the related mechanical anisotropy.     

合成孔径雷达干涉测量原理与应用

合成孔径雷达（SAR）是一种微波相干成像方法，应用不同波段的雷达信号可以对地球表面不同的散射特性成像。合成孔径雷达干涉（InSAR）是将两个不同轨道位置或不同时间获得的复数SAR数据进行相位差分处理，从这些差分干涉数据中可以提取特别有用的信息，用于绘制地形图，测量诸如地震、火山、冰川运动等造成的地形变，研究植被覆盖特性、洋流等。介绍了InSAR的基本原理与应用，并对影响干涉结果的一些重要因素进行了分析。     

大气折射对InSAR影响的定量分析

星载SAR重复轨道干涉利用不同时间观测的SAR影像数据形成干涉图，干涉相位中包含有成像几何、大气、地形以及地面形变等信息。为此，分析了干涉图中大气参数(气压、温度与相对湿度)对干涉相位的影响，计算了参数变化对干涉相位、高程与形变误差的影响量，并以图形方式描述了分析结果。     

Simulating Astrophysical Jets in Laboratory Experiments

Pulsed-power technology and appropriate boundary conditions have been used to create simulations of magnetically driven astrophysical jets in a laboratory experiment. The experiments are quite reproducible and involve a distinct sequence. Eight initial flux tubes, corresponding to eight gas injection locations, merge to form the jet, which lengthens, collimates, and eventually kinks. A model developed to explain the collimation process predicts that collimation is intimately related to convection and pile-up of frozen-in toroidal flux convected with the jet. The pile-up occurs when there is an axial non-uniformity in the jet velocity so that in the frame of the jet there appears to be a converging flow of plasma carrying frozen-in toroidal magnetic flux. The pile-up of convected flux at this “stagnation region” amplifies the toroidal magnetic field and increases the pinch force, thereby collimating the jet.     

映秀-北川断裂带北川段唐家湾滑坡活动历史与形成机制

以映秀-北川断裂带北川段唐家湾滑坡为研究对象,基于地形资料、多期遥感与航拍影像,结合¹⁴C测年的方法,细分了唐家湾滑坡的活动历史,分析了2016年唐家湾滑坡再次复活的主要控制因素。研究结果表明：（1）唐家湾斜坡历史上至少发生过四期滑动,其中第一期次滑坡发生在全新世以前;第二期次滑坡发生于全新世初期;第三期次滑坡发生在2008年汶川地震时期,系龙门山断裂带活动过程中产生的同震滑坡;第四期次滑坡分别发生在2016年和2018年,属于断裂带滑坡堆积体的再次局部复活;（2）2016年唐家湾滑坡的形成与断裂活动、河流侧蚀和水等因素有关,其中,上覆滑坡堆积体、下伏高陡基岩形成的二元斜坡结构,是唐家湾滑坡发生的决定性条件;断裂活动及其导致的浅地表最大主应力偏转是唐家湾滑坡变形的重要内因;（3）以唐家湾滑坡为例,初步讨论了基于地形条件控制的断裂带滑坡堆积体复活的地质模型,其形成演化表现为断裂带活动和河流侵蚀形成滑坡（或陡峭地形）→先期滑坡后壁（或陡峭地形）接受上部老滑坡堆积→二元斜坡结构控制下的老滑坡复活变形。该滑坡为研究地形控制断裂带滑坡复活提供了独特的案例,研究成果对于理解和评估该类滑坡,开展综合防治等方面具有重要的借鉴价值。