基于遥感影像的海岸线提取方法综述

近年来,全球气候变暖等原因导致海平面不断升高,人类对海岸带的开发也越来越频繁,海岸带的变化比以前更为活跃,因此精确快速地提取出海岸线并实时监测其变化对我国海岸带的开发规划与利用具有重要的意义。本文详细梳理了国内外利用光学遥感、微波遥感和雷达遥感手段提取瞬时水边线或理论海岸线的方法,对各种经典方法和一些近年来出现的新方法进行了分析和比较,并指出各种方法的适用情况和不足。最后,针对目前中国在此方面的研究现状给出了一些建议。     

室内位置云平台关键技术研究

针对室内定位普遍存在的连续性和可用性问题,该文研究搭建了位置服务私有云,实现了室内混合云定位关键技术。利用硬件资源虚拟化,实现了动态部署、弹性计算、按需调配的云计算服务。提出了信标节点校正和自主轨迹推算的混合云定位技术,改进了室内定位的连续性和可用性,定位精度达到了约2m。利用微服务管理调度技术及其云推送服务组件,解决了大规模用户在线服务和数据通信瓶颈。开发了大众位置服务云端软件和终端APP,集成了室内地图、混合云定位服务,实现了室内位置云服务。     

城市地下综合管线质检系统设计与实现

针对城市地下综合管线普查数据量大、内容多、质量要求高等特点,传统的检查手段难以满足高效准确地开展质量检验的问题,本文分析了地下综合管线数据特点,探讨了该类成果质量检查内容与方法。提出了一种内外业一体化地下管线质检系统的构建方案。系统由基于平板的外业快速巡查子系统和基于算子集群的内业全自动化质检子系统组成,采用数据库管理模式,两个子系统可以无缝对接。应用表明,利用该系统可以有效提高质检的信息化程度,提升质检工作效率,保障检查结果的准确可靠。     

基于指标权重分析的海洋生态文明绩效考核评价研究

海洋生态文明绩效评价工作日益被重视,构建一套既科学合理又易操作的海洋生态文明绩效评价系统十分必要。文章在已有海洋生态文明绩效评价指标体系基础上,分别采用主观赋权法层次分析法和客观赋权法主成分分析法,结合综合赋权法乘法合成归一法分析指标权重,重新构建海洋生态文明绩效评价模型。并提出下一步要结合实际数据对评价指标进行进一步优化筛选,考虑加入公众参与的内容,对评价模型使用不同的建模方法进行比较和改进,对评价结果进行成因分析,对评价模型进行更优化的系统设计并实现。以期为海洋生态文明绩效评价提供简单科学的方法。     

Analysis of DNA Methylation of <Emphasis Type="Italic">Gracilariopsis lemaneiformis</Emphasis> Under Temperature Stress Using the Methylation Sensitive Amplification Polymorphism (MSAP) Technique

Gracilariopsis lemaneiformis is an economically important agarophyte, which contains high quality gel and shows a high growth rate. Wild population of G. lemaneiformis displayed resident divergence, though with a low genetic diversity as was revealed by amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) analyses. In addition, different strains of G. lemaneiformis are diverse in morphology. The highly inconsistence between genetic background and physiological characteristics recommends strongly to the regulation at epigenetic level. In this study, the DNA methylation change in G. lemaneiformis among different generation branches and under different temperature stresses was assessed using methylation sensitive amplified polymorphism (MSAP) technique. It was shown that DNA methylation level among different generation branches was diverse. The full and total methylated DNA level was the lowest in the second generation branch and the highest in the third generation. The total methylation level was 61.11%, 60.88% and 64.12% at 15°C, 22°C and 26°C, respectively. Compared with the control group (22°C), the fully methylated and totally methylated ratios were increased in both experiment groups (15°C and 26°C). All of the cytosine methylation/demethylation transform (CMDT) was further analyzed. High temperature treatment could induce more CMDT than low temperature treatment did.     

Upper Paleozoic Marine Shale Characteristics and Exploration Prospects in the Northwestern Guizhong Depression,South China

Multiple sets of organic-rich shales developed in the Upper Paleozoic of the northwestern Guizhong Depression in South China. However, the exploration of these shales is presently at a relatively immature stage. The Upper Paleozoic shales in the northwestern Guizhong Depression, including the Middle Devonian Luofu shale, the Nabiao shale, and the Lower Carboniferous Yanguan shale, were investigated in this study. Mineral composition analysis, organic matter analysis(including total organic carbon(TOC) content, maceral of kerogen and the vitrinite reflection(Ro)), pore characteristic analysis(including porosity and permeability, pore type identification by SEM, and pore size distribution by nitrogen sorption), methane isothermal sorption test were conducted, and the distribution and thickness of the shales were determined, Then the characteristics of the two target shales were illustrated and compared. The results show that the Upper Paleozoic shales have favorable organic matter conditions(mainly moderate to high TOC content, type Ⅰ and Ⅱ_1 kerogen and high to over maturity), good fracability potential(brittleness index(BI) 40%), multiple pore types, stable distribution and effective thickness, and good methane sorption capacity. Therefore, the Upper Paleozoic shales in the northern Guizhong Depression have good shale gas potential and exploration prospects. Moreover, the average TOC content, average BI, thickness of the organic-rich shale(TOC 2.0 wt%) and the shale gas resources of the Middle Devonian shales are better than those of the Lower Carboniferous shale. The Middle Devonian shales have better shale gas potential and exploration prospects than the Lower Carboniferous shales.     

2001—2018年黄土高原植被覆盖人为影响时空演变及归因分析

基于2001—2018年的MODIS-NDVI和MODIS-LST以及土地利用、交通、人口等多种人文社会数据,通过温度植被干旱指数反映黄土高原土壤水分状况,利用残差法剔除土壤水分得到植被覆盖变化的人为影响,辅以趋势分析、Hurst指数、地理探测器等方法探讨了黄土高原植被覆盖的人为影响变化特征、未来变化趋势以及人为影响的...     

基于文本分析法的沙漠型5A级旅游景区游客感知与旅游行为研究

基于文本分析法,使用词频分析和语义网络分析6个5A级沙漠型旅游景区的在线评论内容。结果表明：（1）沙漠旅游正在向大众旅游发展,可以分为观光型旅游景区、过渡性旅游景区、综合性旅游景区3个阶段;（2）核心吸引物是自然资源,以“沙+水”模式为主,游客感知差异明显;（3）出游方式倾向于亲子游和自助游,孩子的旅游体验是亲子游中的关键,线上攻略是自助游游客获取信息的重要渠道,行程规划倾向于目的地景区组合,景区效率、收费、服务态度、游客数量与基础设施是影响旅游体验的重要因素。针对沙漠旅游提出了合理开发沙漠资源、重视景区间协调发展、综合发展景区功能、完善景区基础设施、提高景区服务质量的建议。     

2020年4月1日四川石渠5.6级地震总结

系统梳理2020年4月1日四川石渠5.6级地震震前地震活动异常特征、地球物理观测异常以及区域构造情况,结果如下:①地震活动:石渠5.6级地震震中区域属于历史弱震区,震前出现前兆震群,也是其前震活动;②地球物理观测:出现8项异常,其中形变5项,电磁3项,且电磁异常对于该地震具有预测意义;③综合方法:地震发生前,震中附近存...     

1：5万区域地质调查中第四纪地质的研究内容与图件表示原则及方法

随着国民经济建设中第四纪沉积物和环境研究的需要增多,第四纪地质研究在１：５万区域地质调查中逐渐得到重视,为满足不同部门的需要,第四纪地质图除传统的图件外,还包括第四纪资源图,第四纪环境地质图和第四纪灾害地质图三大类图件。其表示原则有两条,一是依服务的对象而定;二是根据研究的内容而定。