南太行山东麓煤田瓦斯突出主控地质因素分析     

张明杰  侯明辉  付帅 《中国煤炭地质》2013,25(3)

根据南太行东麓二1煤层煤与瓦斯突出特征,应用煤与瓦斯突出综合假说,从煤层瓦斯生成、运移、储存的角度,分析研究了岩浆热液作用、地质构造、煤层埋深等因素对煤层煤质、煤层生烃能力、瓦斯含量和压力等煤层瓦斯参数及瓦斯突出因素的影响,确定岩浆热作用对瓦斯突出具有严重影响作用,地质构造、煤层埋深等因素对瓦斯突出具有中等影响作用和一般影响作用,该结论为地质勘探、矿井设计与生产规划、矿井瓦斯防治提供了理论依据.  相似文献   

An Uncertainty Quantification Framework for Studying the Effect of Spatial Heterogeneity in Reservoir Permeability on CO2 Sequestration     

Zhangshuan Hou  Dave W. Engel  Guang Lin  Yilin Fang  Zhufeng Fang 《Mathematical Geosciences》2013,45(7):799-817

A new uncertainty quantification framework is adopted for carbon sequestration to evaluate the effect of spatial heterogeneity of reservoir permeability on CO₂ migration. Sequential Gaussian simulation is used to generate multiple realizations of permeability fields with various spatial statistical attributes. In order to deal with the computational difficulties, the following ideas/approaches are integrated. First, different efficient sampling approaches (probabilistic collocation, quasi-Monte Carlo, and adaptive sampling) are used to reduce the number of forward calculations, explore effectively the parameter space, and quantify the input uncertainty. Second, a scalable numerical simulator, extreme-scale Subsurface Transport Over Multiple Phases, is adopted as the forward modeling simulator for CO₂ migration. The framework has the capability to quantify input uncertainty, generate exploratory samples effectively, perform scalable numerical simulations, visualize output uncertainty, and evaluate input-output relationships. The framework is demonstrated with a given CO₂ injection scenario in heterogeneous sandstone reservoirs. Results show that geostatistical parameters for permeability have different impacts on CO₂ plume radius: the mean parameter has positive effects at the top layers, but affects the bottom layers negatively. The variance generally has a positive effect on the plume radius at all layers, particularly at middle layers, where the transport of CO₂ is highly influenced by the subsurface heterogeneity structure. The anisotropy ratio has weak impacts on the plume radius, but affects the shape of the CO₂ plume.  相似文献   

从生态系统服务角度探究土地利用变化引起的生态失衡——以莱州湾海岸带为例     

李晓炜  侯西勇  邸向红  苏红帆 《地理科学》2016,36(8):1197-1204

以莱州湾海岸带为研究区,基于2000年、2005年、2010年和2014年多时相土地利用数据,应用生态系统服务价值评估,逐层剖析土地利用变化对生态系统服务失衡特征的影响。结果表明：莱州湾海岸带供水与空气组分调节服务呈负值,2000~2014年,生态系统服务总价值丧失43%（147亿美元/a）,生态系统服务多样性降低甚至丧失,呈向海性,围填海造成162亿美元生态损失。土地利用变化方式是造成生态失衡的主因,主要包括：交通工矿、盐田、养殖及城镇扩张,滩涂、河口湿地、耕地被侵占。滩涂和河口湿地减少,导致废物处理、栖息地、基因多样性、干扰调节、侵蚀防护服务丧失严重,交通工矿和城镇扩张,引起供水服务负效应加剧。  相似文献   

青海湖沉积柱Dinoflagellate藻类基因丰度变化及其古气候环境的指示意义          下载免费PDF全文

杨渐  蒋宏忱  吴耿  李高远  侯卫国  董海良 《盐湖研究》2016,24(1)

近年来,有学者通过古DNA方法成功地重建了海洋沉积记录中古微生物群落变化,并借此反演了当地古环境-气候变化。然而,此种方法对于陆地湖泊沉积记录是否适用仍然有待研究。本文采用聚合酶链式反应（PCR, Polymerase Chain Reaction）、变性梯度凝胶电泳（DGGE,Denaturing Gradient Gel Electrophoresis）与实时荧光定量聚合酶链式反应（Q-PCR,Quantitative PCR）相结合的综合分析技术手段,系统研究青海湖5.8米（时间跨度为～18500年）沉积柱dinoflagellate真核藻类多样性和丰度变化。研究结果显示青海湖Dinoflagellate藻18S rRNA基因序列主要与海洋型藻类Woloszynskia halophila和Scrippsiella hangoei相近（～98%序列相似性）。定量Q-PCR结果显示,每克沉积物含有dinoflagellate藻类18S rRNA基因丰度范围为2.27×103～8.55×106拷贝。另外,Dinoflagellate藻类18S rRNA基因丰度与总有机碳含量成显著正相关（r = 0.408,p = 0.0001）。对比分析揭示较高的藻类丰度对应高总有机碳含量和较低的可溶解性盐电导率;反之,较低的藻类丰度对应较高的可溶解性盐电导率和较低的总有机碳含量。在青海湖区,总有机碳指示着季风降雨变化并间接地指示着外源输入和湖泊营养状况变化,然而可溶性盐电导率则指示着湖泊盐度变化。综上所诉,青海湖沉积柱Dinoflagellate藻类丰度可能响应着历史时期湖泊营养状况和盐度波动情况。  相似文献   

Chlorinated organic contaminants in surface sediments from the Yangtze Estuary and nearby coastal areas,China   总被引：12，自引：0，他引：12  

Liu M  Yang Y  Hou L  Xu S  Ou D  Zhang B  Liu Q 《Marine pollution bulletin》2003,46(5):672-676

  相似文献   

2006年上半年全国生态气象监测与评估研究   总被引：2，自引：0，他引：2  

毛留喜  李朝生  侯英雨  钱拴  唐世浩 《气象》2006,32(12):88-95

为了对2006年上半年全国生态环境进行以气象条件为主要驱动因子的监测与评估，研究创建了基于植被第一性生产力（NPP）估算的生态气象监测与评估指数（EMI）模型。通过计算生态气象指数、划分生态气象等级，进行生态气象监测与评估。2006年上半年全国大部地区生态气象条件较差，平均生态气象优劣评价指数仅为-30；生态气象等级好、中、差的比例大约为2：45：53。对我国生态及生产起重要作用的林地、草灌、农田的生态气象等级在中等以上的面积较2005年上半年显著减少。1—6月平均生态气象指数在逐月降低，虽处于正常等级范围之内，但5、6月份处于临界状态已接近较差等级。其主要原因是持续干旱和低温冷害的影响，多起森林与草原火灾和大范围高频度的沙尘天气与生态状况互为因果。所构建的生态气象监测评估模型，有良好的理论基础和科技含量，也有较好的时空分辨能力，可以进行生态气象定量监测和评价，监测与评估结果科学、客观、合理，能够反映气象条件对生态环境的作用。  相似文献   

Real-time Solution of Atomic Clock Operating Parameters Based on Adaptive Kalman Filtering     

Hou Juan  Dong Shao-wu  Qu Li-li  Wang Ji-gang  He Zai-min 《Chinese Astronomy and Astrophysics》2013

The real-tine and accurate knowledge of the operation of an atomic clock is of great significance to satellite navigation and time keeping. In the light of the problems which exist in the real-time solution of the atomic clock operating parameters by means of the standard Kalman filtering, the method for applying the adaptive Kalman filtering model based on the prediction residual to the real-time solution of the clock parameters is proposed. An adaptive factor is constructed by the model based on the standard Kalman filtering model so that the accurate and reliable estimates of the operating parameters may be given rather fast after the frequency modulation or phase modulation of the atomic clock. Finally, in combination with the 3 computational examples of the work on the navigation and time keeping, the effectiveness of the method is verified.  相似文献   

Bifurcating families around collinear libration points   总被引：1，自引：0，他引：1  

X. Y. Hou  L. Liu 《Celestial Mechanics and Dynamical Astronomy》2013,116(3):241-263

The planar and the vertical Lyapunov families are two basic periodic families around the collinear libration points. The stability curves of these two families are given first, and then periodic families bifurcating from them are explored in detail. Several properties of these bifurcating families are found. This study follows a series of the authors’ publications on periodic families around the libration points in the restricted three-body problem.  相似文献   

High-order solutions of invariant manifolds associated with libration point orbits in the elliptic restricted three-body system   总被引：1，自引：0，他引：1  

Hanlun Lei  Bo Xu  Xiyun Hou  Yisui Sun 《Celestial Mechanics and Dynamical Astronomy》2013,117(4):349-384

High-order analytical solutions of invariant manifolds, associated with Lissajous and halo orbits in the elliptic restricted three-body problem (ERTBP), are constructed in this paper. The equations of motion of ERTBP in the pulsating synodic coordinate system have five equilibrium points, and the three collinear libration points as well as the associated center manifolds are unstable. In our calculation, the general solutions of the invariant manifolds associated with Lissajous and halo orbits around collinear libration points are expressed as power series of five parameters: the orbital eccentricity, two amplitudes corresponding to the hyperbolic manifolds, and two amplitudes corresponding to the center manifolds. The analytical solutions up to arbitrary order are constructed by means of Lindstedt–Poincaré method, and then the center and invariant manifolds, transit and non-transit trajectories in ERTBP are all parameterized. Since the circular restricted three-body problem (CRTBP) is a particular case of ERTBP when the eccentricity is zero, the general solutions constructed in this paper can be reduced to describe the dynamics around the collinear libration points in CRTBP naturally. In order to check the validity of the series expansions constructed, the practical convergence of the series expansions up to different orders is studied.  相似文献   

以“不变特征点集”为控制数据集的遥感图像自动化处理框架     

唐娉  郑柯  单小军  胡昌苗  霍连志  赵理君  李宏益 《遥感学报》2016,20(5):1126-1137

全球变化研究需要将多种传感器光谱波长接近的图像波段一起使用,以满足遥感应用对时间分辨率和区域覆盖的要求,这给遥感图像处理提出了新要求,涉及多传感器多时相数据几何定位一致性问题、辐射归一化问题及地类属性标识一致性问题以及高度自动化处理的问题。针对上述几方面问题,提出了一个基于"不变特征点集"IFPs(Invariant Feature Points set)作为控制数据集的区域级遥感图像自动化处理框架,将图像的几何空间、辐射值空间和类别属性值空间的时空对齐问题纳入到统一框架,提供了一种间接快速处理的手段和理念,并对构建IFPs的关键技术进行了综述。  相似文献