中国旅游产业投资及旅游发展空间结构响应——基于2000~2015年旅游业三大核心部门数据的分析   总被引：2，自引：1，他引：1  

李涛  刘家明  朱鹤  龙飞  余文婷 《地理科学》2019,39(2):204-213

以旅游业三大核心部门（旅游饭店、旅游景区和旅行社）的固定资产和人力资源投资为研究变量,分析了2000~2015年中国旅游产业投资演化及旅游发展空间结构的响应。研究发现,中国旅游产业投资存在与旅游发展总体协调、省域空间分布不均、年际变化多样和部门差异明显的特征;省域旅游发展响应系数的变化,反映了中国旅游产业投资的“时间磨蚀效应”和“绩效累积效应”;在“空间牵引效应”作用下,中国旅游产业投资促进了中国旅游发展空间结构特征由离散型“核式极化”向连续型“域状扩散”转变。最后,提炼了旅游发展对旅游投资空间响应的实质：以投资为驱动,依据循环积累因果机制,促进区域旅游产业可持续增长。  相似文献   

鄂尔多斯盆地西南缘奥陶系深水牵引流沉积   总被引：4，自引：0，他引：4  

刘成鑫  高振中  纪友亮  吴晓龙 《海洋地质与第四纪地质》2005,25(2):31-36

深水牵引流沉积是沉积学中的一个重要研究领域，包括内潮汐、内波沉积和等深流沉积两大类，主要发育于海洋深水区。深水牵引流沉积的研究起步较晚，目前主要集中于现代深海沉积和野外露头研究，对深埋地下的古代深水牵引流沉积发现较少，其所具有的油气潜能还不被人们所认识。本文论述了鄂尔多斯盆地西南缘奥陶系内潮汐沉积、等深流沉积的特征和沉积类型。内潮汐沉积是在研究区首次发现，以灰色中一细砂岩为主，部分为粗粉砂岩，单层厚十余厘米至数十厘米，砂岩以普遍发育双向交错纹理为特征。等深岩丘主要由3种碳酸盐等深岩组成，即砂屑等深岩、粉屑等深岩和灰泥等深岩，共发育有4种层序样式。最后，阐明了其油气勘探意义，并分析了其潜在的油气勘探价值。  相似文献   

A new approach for modelling slip lines in geological materials with cohesive models   总被引：1，自引：0，他引：1  

T. Rabczuk  P.M.A. Areias 《国际地质力学数值与分析法杂志》2006,30(11):1159-1172

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X‐ray tomography of tsunami deposits: Towards a new depositional model of tsunami deposits          下载免费PDF全文

Simon Falvard  Raphaël Paris 《Sedimentology》2017,64(2):453-477

X‐ray computed microtomography is used to obtain high resolution imagery of a historical tsunami deposit in Andalusia, Spain (1755 Lisbon tsunami). The technique allows characterization of grain‐size distribution, structures, component analysis and sedimentary fabric of fine‐grained unconsolidated tsunami deposits at resolutions down to particle scale. The results are validated by comparing to data obtained using other techniques such as laser diffraction, anisotropy of magnetic susceptibility and X‐ray microfluorescence on the same deposits. Specific technical details such as sampling, scanning and image processing methods, and further improvements are addressed. The use of X‐ray computed microtomography provides new insights into the stratigraphy of the deposits and gives access to significantly more detailed view of key sedimentary features such as mudlines, rip‐up clasts, crude laminations, convolutions, floating outsized clasts and contacts between successive units. This analysis of the 1755 tsunami deposits using X‐ray computed microtomography allows the proposal of new hypotheses for the sedimentary processes forming tsunami deposits. Deposition by settling is limited and the section analysed here is dominated by a high shear stress leading to the development of traction carpets, with laminated mudlines corresponding to the basal frictional region of these carpets. The onset of the tsunami backwash is marked by a micro‐vortex resembling Kelvin–Helmoltz instabilities.  相似文献   

Compression–shear coupling rheological constitutive model of the deep-sea sediment     

Feng Xu  Jie Zhang  Wenbo Ma 《Marine Georesources & Geotechnology》2018,36(3):288-296

In deep-sea mining engineering, the compression–shear coupling effect of the sediment on the moving tracked mining vehicle must be considered, since it is proved to be existing in compression–shear creep test of the sediment simulant. Based on the endochronic theory, the compression–shear coupling rheological model is established by the definition of intrinsic time and calculation of deviatoric tensor, where the coupling rheological parameters can be obtained by the compression–shear creep test. For simulating sinkage and traction force of the moving tracked mining vehicle, the compression–shear coupling rheological model as well as compressive rheological model and direct shear rheological model (regardless of coupling rheological effect) is programmed and introduced into RecurDyn software (with only traditional elastic–plastic constitutive model) for comparison. Research results show that the sinkage is the largest, and the traction force is the smallest under the compression–shear coupling rheological model, which could better reflect the worse working situation. The compression–shear coupling rheological model could provide theoretical basis for optimal design and safety assessment of the tracked mining vehicle.  相似文献   

深海取样绞车牵引卷筒上钢缆张力分析   总被引：4，自引：2，他引：2  

翟庆光  聂杰  康岳伟 《海洋技术学报》2008,27(2):28-30

文中根据深海取样绞车的钢缆和牵引卷筒之间力的关系,利用微积分学原理,对钢缆在牵引卷筒上的张力变化进行了分析,建立了钢缆张力、钢缆与卷筒间的摩擦系数、钢缆在卷筒上的包角等参数之间的关系式,并通过实例对该关系式进行了验证。  相似文献   

遥控水下机器人脐带缆收放绞车设计及牵引力分析   总被引：1，自引：0，他引：1  

康守权  张奇峰 《海洋工程》2010,28(1)

脐带缆收放技术是有缆遥控水下机器人的一项关键技术,该技术直接影响水下机器人载体的收放及作业过程中脐带缆的安全。针对目前水下机器人收放系统中脐带缆收放技术的特点,给出了一种具有自动排缆、低张力缠绕、能够提供大牵引力和安全制动功能的紧凑新式脐带缆绞车方案,并对牵引绞车与储藏绞车之间脐带缆张力与牵引绞车的牵引力进行了理论分析,给出了二者之间的关系函数。  相似文献