一体化进程对旅游经济的空间溢出效应——以长三角城市群为例

利用长三角城市群各地区2011—2018年的面板数据,在测算一体化指数基础上,借助空间杜宾模型揭示一体化进程对旅游经济的空间溢出效应。主要结论有：长三角城市群一体化指数在空间上分布不均衡,整体上呈现出从省会城市向周边递减的格局。空间杜宾模型能够较好地对一体化进程的溢出效应进行定量估算,从空间杜宾模型的估算结果看,长三角城市群一体化进程对旅游经济有着显著的溢出效应,本地一体化进程每提高1%,将促进周边地区旅游经济增加0.575%。就本地效应而言,一体化进程各维度对旅游经济具有显著的正向影响,基础设施一体化是其中较为重要的因素;就溢出效应而言,一体化进程各维度对旅游经济的影响均低于本地效应,基础设施一体化对周边地区的旅游经济有一定的负向影响。未来长三角城市群旅游业高质量发展一方面需要重视本地一体化,同时也要重视一体化的空间溢出效应,营造良好的周边环境,出台相关政策,加强区域间的协调与合作。     

The S receiver functions: synthetics and data example

Recently, the S receiver function method has been successfully developed to identify upper mantle interfaces. S receiver functions have the advantage of being free of S -wave multiple reflections and can be more suitable than P receiver functions for studying mantle lithosphere. However, because of specific ray geometry and interference of diverse phases, the S receiver function method has some technical difficulties and limitations. We use synthetic seismograms to demonstrate the feasibility and limitations of S receiver functions for studying mantle structures. Full-wavefield seismograms were calculated using the reflectivity method and processed to generate synthetic S receiver functions for S , SKS and ScS waves. Results show that S receiver functions can be obtained from waveforms of S , SKS and ScS waves. The synthetic S receiver functions for these incident waves show S -to- P converted phases at all discontinuities in the crust and upper mantle. Useful ranges of epicentral distances for calculation of S receiver functions are: 55°–85° for S , >85° for SKS and 50°–75° for ScS waves. We apply both the S and P receiver function methods to data recorded at broadband station YKW3 in Northwest Canada. The study shows that there is significant agreement among different receiver function methods, and demonstrates the usefulness of S receiver functions for imaging the mantle lithosphere.     

城市三维地质建模及其在城镇化建设中的应用

城市是建设在地质体之上的,这就注定城市的建设发展离不开地质工作的支撑。城市三维地质建模是三维信息技术在城市地质领域的一个典型应用,可大大提升城市地质调查成果的表达方式,提高城市地质资源环境的评价预测能力,对中国正在大力实施的城镇化建设具有重要支撑作用。对城市三维地质模型进行了分类,分析了城市三维地质模型的特点;研究了城市三维地质模型的构建,并对城市三维地质结构模型的构建进行了详细阐述;以北京市为例,给出了城市三维地质建模服务城市规划、地铁隧道选线施工、新城建设、重点工程选址、资源开发等方面的应用实例。     

The Formation and Evolution of Uvarovite in UHP Serpentinite and Rodingite and its Constraints on Chromium Mobility in the Oceanic Subduction Zone

The uvarovite-andradite and uvarovite-andradite-grossular solid-solution series are rare in nature. The discovery of uvarovite-andradite in serpentinite and rodingite from the ultra-high pressure (UHP) metamorphic belt in southwestern Tianshan provided an opportunity to investigate its behavior in the subduction zone. Uvarovite (defined as chromium-garnet) from serpentinite is homogeneous in a single grain, covering compositions in the uvarovite-andradite solid solution series of Adr58–66Uv33–41, with few grossular components. Uvarovite from rodingites contain various Cr2O3 contents (1.7–17.9 wt%) and mineral compositions being in the range of Adr21–31Uv41–50Grs22–37, Adr52–90Uv5–25Grs0–21 and Adr19–67Uv3–63Grs13–42. Discontinuous chemical variation of uvarovite from core to rim indicates that uvarovite formed by consuming andradite and chromite, which could provide Ca, Cr, Al and Fe. Raman signals of water were identified for uvarovite from both serpentinite and rodingite, with high water content in uvarovite from serpentinite. The high pressure mineral assemblage, as well as the association with perovskite, indicated that the studied uvarovite from serpentinite and rodingite was formed through high pressure metamorphism, during the subduction zone serpentinization and rodingitization. High alkaline and highly reduced fluids released from serpentinization or rodingitization in the oceanic subduction zone promote the mobility of chromium and enable its long-distance migration.     

云南禄劝县皎西乡土壤氡测量在易门-罗茨隐伏断裂研究中的应用

易门-罗茨断裂带是多期活动的大规模断裂带,以易门-罗茨断裂为主断裂。在禄劝县皎西一带,断裂带控制了南北向的串珠状第四系盆地,盆地内第四纪沉积物厚数米至数十米,主要的控盆隐伏断裂位置、特征难以确定。采用地质调查与土壤氡测量相结合的方法,查明了区内控盆隐伏断裂的位置、产状、宽度等。调查结果与地貌和区域构造特征吻合较好,因此认为,土壤氡测量适用于山间盆地内隐伏活动断裂的调查。     

叠层橡胶支座隔震结构地震响应的突变分析

为全面分析地震破坏过程中由非线性引起的,如突变和滞后效应等某些复杂特性,本文在现有的动力分析模型基础上引入了非线性恢复力,并用突变理论分析方法对改进后的模型进行分析,结果表明叠层橡胶支座参数的微小变化使响应振幅及其突变值、振幅响应的不稳定区域等特性产生明显变化,反映出隔震结构的地震响应特性对参数变化非常敏感。由于支座阻尼的耗能作用,当阻尼较大或激振力、非线性参数较小时,地震响应的突变现象消失,产生"伪线性"特性。     

SMA复合支座-巨型框架结构体系减震效果分析

在研究形状记忆合金（SMA）绞线-叠层橡胶复合支座基础上,本文提出了SMA复合支座-巨型框架减震结构体系,建立了SMA复合支座-巨型框架减震结构体系的计算模型和运动方程,研究了该结构的动力反应特性,并将其与普通巨型框架结构、应用普通橡胶支座巨型框架结构进行了非线性时程对比分析。结果表明,SMA复合支座-巨型框架减震结构体系能有效地减小结构的地震响应,同时避免了地震时主次结构之间产生碰撞破坏。     

2011年呼伦贝尔市闪电密度特征初探

利用2011年呼伦贝尔市9部ADTD型地闪定位仪提供的地闪观测资料,对呼伦贝尔市地闪发生时空分布特征进行分析。结果表明:云地闪中负闪约占92.62%;夏季地闪活动最强,春、秋两季次之,冬季最弱,地闪主要集中在7—8月;地闪的发展有明显的日变化,呈双峰双谷形式,地闪活动下午最活跃;闪电密度的空间分布与地形和下垫面的性质关系密切,地闪的大值中心位于南北走向的大兴安岭山脉东西两侧,白天地闪密度大值中心位于大兴安岭山脉与松嫩平原过渡区山坡上,而夜间地闪密度大值中心则位于呼伦贝尔高原与大兴安岭山脉的过渡区沙丘地带。     

城市三维地质建模及其在城镇化建设中的应用

城市是建设在地质体之上的,这就注定城市的建设发展离不开地质工作的支撑。城市三维地质建模是三维信息技术在城市地质领域的一个典型应用,可大大提升城市地质调查成果的表达方式,提高城市地质资源环境的评价预测能力,对中国正在大力实施的城镇化建设具有重要支撑作用。对城市三维地质模型进行了分类,分析了城市三维地质模型的特点;研究了城市三维地质模型的构建,并对城市三维地质结构模型的构建进行了详细阐述;以北京市为例,给出了城市三维地质建模服务城市规划、地铁隧道选线施工、新城建设、重点工程选址、资源开发等方面的应用实例。     

基于改进雨林模糊神经网络模型的页岩储层总有机碳含量评价方法

由于采用常规测井曲线评价页岩储层总有机碳含量的精度不高,泛化能力不强,需要大量样本。针对这些问题,改 进了神经网络算法,以增加模型的预测能力。利用模糊系统优化细胞神经网络结构,以增强其逻辑推理能力,提高其对模 糊数据的敏感性;选择能有效避免“虚拟碰撞”的雨林算法,并针对其存在的缺陷进行改进;利用改进雨林优化算法对网 络的初始权值阈值进行优化,避免网络陷入局部极小。分析测井特征曲线的物理意义,选择密度测井曲线与自然伽马能谱 测井曲线作为网络的输入,以总有机碳含量作为输出,通过70块岩心样本网络学习与26块岩心样本预测,证明了新网络模 型的优越性。结果表明,新模型回判将相对误差从23.189%减小到17.185%,预测相对误差由52.421%减小到15.158%,具 有更强的学习能力与泛化能力,更适用于页岩储层总有机质含量的测井评价。