工程破坏区植被发育动态过程的研究 --以古尔班通古特沙漠为例

通过样方法及植被调查法,从纵向和横向两个不同方向对工程破坏后的沙地植被进行比较研究。在纵向上,由于植被恢复时间的不同,其恢复的程度也不同。植被恢复状况可明显的分3个阶段:定居前期(1～6a)主要以多年生羽叶三芒草和小半灌木绢蒿为主;中期(7～11a)主要以多年生小半灌木青杆沙蒿为主;后期(12～16a)主要生长着多年生麻黄及草本沙苔,地表出现大面积的生物结皮。在横向上,将恢复后期的植被与原始植被进行比较。通过对植被发育不同阶段过程中物种重要值、物种多样性、丰富度及生活型的变化等方面的调查,发现在不同阶段,各物种的重要值发生了不同的变化,物种多样性指数,均匀度指数,丰富度指数到后期均增大。     

香港世界地质公园晚侏罗世荔枝庄组岩石组合及其成岩地质过程解析

中国东南大陆晚侏罗世地层普遍缺失,仅零星见于个别地区,香港新界东北的荔枝庄组即为其一。荔枝庄组出露于香港世界地质公园沉积岩园区的荔枝庄地区,自下往上由火山岩—沉积岩—火山岩组合而成,沉积岩中发育大型包卷层理和滑塌构造等典型沉积构造,是香港地区最具代表性的晚侏罗世火山—沉积岩系。通过实测地层剖面研究,确定其成岩过程大体上可划分为早期普林尼式火山爆发、中期破火山口湖相沉积和晚期普林尼式火山爆发三个阶段,以湖相沉积作用为主、火山喷发作用为辅;受晚期火山岩浆活动的影响,沉积岩层普遍发生硅化或炭化。荔枝庄组独特的岩石组合与形成的古地理环境,为探讨中国东南大陆中生代火山活动—沉积作用方式与成岩过程,提供了难得的研究实例。     

伟晶岩型锂矿成矿构造背景研究

锂是银白色的、自然界最轻的金属,广泛应用于纺织、陶瓷、冶金、核能、新能源等领域,有“高能金属”、“21世纪的能源金属”之称。锂矿床按成因类型可分为内生和外生两种类型,内生型可具体分为花岗伟晶岩型、花岗岩型、云英岩型和岩浆热液型,外生型则包括盐湖型及地下卤水型（赵一鸣等,2004）。伟晶岩型锂矿主要开采锂辉石、透锂云母、锂云母、磷铝锂石等,是锂矿资源的重要来源。     

高建筑对周围建筑雷击保护距离的模拟

在已有先导连接参数化方案的基础上,选取近地面层为研究区域,保持方案中其他基本参量不变,通过改变闪电的空间形态,在同一建筑分布的背景下进行多次闪电模拟。研究多个建筑之间的屏蔽作用以及建筑雷击保护距离与建筑相关特征参数之间的关系,结果表明:高建筑对矮建筑具有屏蔽作用,并存在一个临界保护距离,当高、矮建筑高度分别为190 m和165 m,宽度均为20 m时,建筑之间的距离在12 m以内,矮建筑受高建筑完全保护不遭受雷击;建筑之间的距离超过12 m,矮建筑遭雷击次数明显增多。     

附有物理量和气象条件约束的光学卫星国土观测有效覆盖率评估

传统光学卫星国土观测覆盖评估建立在卫星对地理想覆盖的基础上,并未考虑卫星存储、星地数据传输、观测时长等物理量及观测区域气象因素对于覆盖性能的影响。本文针对光学遥感卫星的国土观测需求.建立国土观测有效覆盖能力评估指标体系,根据卫星数据存储能力、星地数据传输能力、卫星单圈最大观测时长、卫星观测太阳高度角等性能参数,提出了基于物理性能约束下的有效覆盖计算方法。根据气象台站历年气象数据,提出了气象约束因子的计算方法。综合考虑卫星物理性能约束与观测区域气象约束,计算光学遥感卫星对地观测有效覆盖能力。最后根据专家设计的光学遥感卫星国土观测有效覆盖能力评估指标权重,利用层次分析法(AHP)评估光学遥感卫星系统对于国土观测的需求满足程度。试验结果表明,本文方法对于国土观测有效覆盖的估算和评价结果更加精确,更接近于国土观测的实际应用需求,为对地观测有效覆盖能力评估提供了一种更为精确的可行方案。     

历史数据和强化学习相结合的低频轨迹数据匹配算法

针对低频(采样间隔大于1min)轨迹数据匹配算法精度不高的问题,提出了一种基于强化学习和历史轨迹的匹配算法HMDP-Q,首先通过增量匹配算法提取历史路径作为历史参考经验库;根据历史参考经验库、最短路径和可达性筛选候选路径集;再将地图匹配过程建模成马尔科夫决策过程,利用轨迹点偏离道路距离和历史轨迹构建回报函数;然后借助强化学习算法求解马尔科夫决策过程的最大回报值,即轨迹与道路的最优匹配结果;最后应用某市浮动车轨迹数据进行试验。结果表明:本文算法能有效提高轨迹数据与道路匹配精度;本算法在1min低频采样间隔下轨迹匹配准确率达到了89.2%;采样频率为16min时,该算法匹配精度也能达到61.4%;与IVVM算法相比,HMDP-Q算法匹配精度和求解效率均优于IVVM算法,16min采样频率时本文算法轨迹匹配精度提高了26%。     

基于热模拟实验的富有机质泥页岩成岩作用及演化特征

富有机质泥页岩蕴含丰富的油气资源,但成岩研究基础薄弱,已成为制约页岩油气勘探开发进程的重要因素。通过开展成岩热模拟实验,结合扫描电镜观察、流体成分测试及有机酸测试等实验测试手段,全面描述实验过程中所发生的水-岩化学反应,试图揭示泥页岩成岩过程及成岩演化规律。研究结果显示,有机质热演化过程中存在一个较宽的有机酸生成窗口,对孔隙流体性质具有重要影响;长石和方解石存在接力溶蚀现象,长石溶蚀高峰过后紧接着出现方解石溶蚀高峰,但方解石溶蚀窗较窄,此后出现方解石重新沉淀结晶;黏土矿物转化及长石的溶蚀过程中会产生大量自生微晶石英,成链状或簇状胶结泥页岩骨架。泥页岩地层作为一个相对封闭体系,各类成岩作用之间相互关联,相互影响,构成错综复杂的成岩体系,进一步增加其成岩作用研究难度。     

Status of Stratigraphy Research in China

Scientific research and productive practice for earth history are inseparable from the accurate stratigraphic framework and time framework. Establishing the globally unified, precise and reliable chronostratigraphic series and geological time series is the major goal of the International Commission on Stratigraphy(ICS). Under the leadership of the ICS, the countries around the world have carried out research on the Global Standard Stratotype-section and Points(GSSPs) for the boundaries of chronostratigraphic systems. In the current International Chronostratigraphic Chart(ICC), 65 GSSPs have been erected in the Phanerozoic Eonothem, and one has yet been erected in the Precambrian Eonothem. Based on the progress of research on stratigraphy especially that from its subcommissions, the ICS is constantly revising the ICC, and will publish a new International Stratigraphic Guide in 2020. After continual efforts and broad international cooperation of Chinese stratigraphers, 10 GSSPs within the Phanerozoic Eonothem have been approved and ratified to erect in China by the ICS and IUGS. To establish the standards for stratigraphic division and correlation of China, with the support from the Ministry of Science and Technology, the National Natural Science Foundation of China and the China Geological Survey, Chinese stratigraphers have carried out research on the establishment of Stages in China. A total of 102 stages have been defined in the "Regional Chronostratigraphic Chart of China(geologic time)", in which 59 stages were studied in depth. In 2014, the "Stratigraphic Chart of China" was compiled, with the essential contents as follows: the correlation between international chronostratigraphy and regional chronostratigraphy of China(geologic time), the distributive status of lithostratigraphy, the characteristics of geological ages, the biostratigraphic sequence, the magnetostratigraphy, the geological events and eustatic sea-level change during every geological stage. The "Stratigraphical Guide of China and its Explanation(2014)" was also published. Chinese stratigraphers have paid much attention to stratigraphic research in south China, northeast China, north China and northwest China and they have made great achievements in special research on stratigraphy, based on the 1:1000000, 1:250000, 1:200000 and 1:50000 regional geological survey projects. Manifold new stratigraphic units were discovered and established by the regional geological surveys, which are helpful to improve the regional chronostratigraphic series of China. On the strength of the investigation in coastal and offshore areas, the status of marine strata in China has been expounded. According to the developing situation of international stratigraphy and the characteristics of Chinese stratigraphic work, the contrast relation between regional stratigraphic units of China and GSSPs will be established in the future, which will improve the application value of GSSPs and the standard of regional stratigraphic division and correlation. In addition, the study of stratigraphy of the Precambrian, terrestrial basins and orogenic belts will be strengthened, the Stratigraphic Chart of China will be improved, the typical stratigraphic sections in China will be protected and the applied study of stratigraphy in the fields of oil and gas, solid minerals, etc. will be promoted. On the ground of these actions, stratigraphic research will continue to play a great role in the social and economic development of China.     

水库群供调水系统实时调度研究

以大连市复杂水库群供、调水系统为背景,在对系统特性分析的基础上,提出了系统实时调度框架及二层耦合结构模式,设计了以"总量控制、耦合嵌套、多维决策、滚动修正"为核心的实时调度流程。在径流预报方面,提出了基于超越概率的水库群供、调水系统长期入库径流预报方法,结合中期GFS(Global Forecasting System)数值预报技术对不同时段入库径流进行滚动预报。在调度模型方面,采用基于动态规划的建模求解新方法和常规调度方法,为调度决策提供参考。实例研究表明,建立的实时调度系统实现了滚动预报和滚动调度,具备了实时性;实现了宏观总控与局部调整相结合的调度目标,具备了调度决策不同时间尺度耦合嵌套特性,证明了系统的适用性。研究成果对于同类系统实时调度具有重要参考价值。