页岩气基础地质调查皖南地1井钻探施工技术

皖南地1井是部署在安徽省南陵县烟墩镇的一口页岩气基础地质调查井。文章详细介绍了该井的钻探施工工艺技术以及遇到复杂问题的处理方法,并对钻效进行了分析,提出了实现优质高效钻探的措施。项目的顺利实施,梳理了皖南地区地层层序,为页岩气储层理论推测提供了有力的实物数据支撑和验证。     

Geometric-constrained multi-view image matching method based on semi-global optimization

Targeting at a reliable image matching of multiple remote sensing images for the generation of digital surface models, this paper presents a geometric-constrained multi-view image matching method, based on an energy minimization framework. By employing a geometrical constraint, the cost value of the energy function was calculated from multiple images, and the cost value was aggregated in an image space using a semi-global optimization approach. A homography transform parameter calculation method is proposed for fast calculation of projection pixel on each image when calculating cost values. It is based on the known interior orientation parameters, exterior orientation parameters, and a given elevation value. For an efficient and reliable processing of multiple remote sensing images, the proposed matching method was performed via a coarse-to-fine strategy through image pyramid. Three sets of airborne remote sensing images were used to evaluate the performance of the proposed method. Results reveal that the multi-view image matching can improve matching reliability. Moreover, the experimental results show that the proposed method performs better than traditional methods.     

A geometric-based approach for road matching on multi-scale datasets using a genetic algorithm

Object matching is used in various applications including conflation, data quality assessment, updating, and multi-scale analysis. The objective of matching is to identify objects referring to the same entity. This article aims to present an optimization-based linear object-matching approach in multi-scale, multi-source datasets. By taking into account geometric criteria, the proposed approach uses real coded genetic algorithm (RCGA) and sensitivity analysis to identify corresponding objects. Moreover, in this approach, any initial dependency on empirical parameters such as buffer distance, threshold of spatial similarity degree, and weights of criteria is eliminated and, instead, the optimal values for these parameters are calculated for each dataset. Volunteered geographical information (VGI) and authoritative data with different scales and sources were used to assess the efficiency of the proposed approach. According to the results, in addition to an efficient performance in various datasets, the proposed approach was able to appropriately identify the corresponding objects in these datasets by achieving higher F-Score.     

基于优化经验模态分解和聚类分析的滑坡位移智能预测研究

针对三峡库区"阶跃式"滑坡的变形特征,提出了一种新的滑坡位移预测方法。以白水河滑坡ZG118和XD-01监测点位移数据为例,采用基于软筛分停止准则的经验模态分解(SSSC-EMD)将累计位移-时间曲线和影响因子时间序列自适应地分解为多个固有模态函数(IMF),并采用K均值(K-Means)聚类法对其进行聚类累加,得到有物理含义的位移分量(趋势性位移、周期性位移以及随机性位移)和影响因子分量(高频影响因子和低频影响因子)。使用最小二乘法对趋势性位移进行拟合预测;采用果蝇优化-最小二乘支持向量机(FOA-LSSVM)模型对周期性位移和随机性位移进行预测。将各位移分量预测值进行叠加处理,实现滑坡累计位移的预测。研究结果表明,所提出的(SSSC-EMD)-K-Means-(FOA-LSSVM)模型能够预测"阶跃式"滑坡的位移变化规律,且预测精度高于传统的支持向量机回归(SVR)、最小二乘支持向量机(LSSVM)模型;并通过改变训练集长度,进行单因素分析,发现其与预测精度之间呈正相关关系。     

GNSS控制网方案优化与数据处理分析

GNSS布设平面控制网已在工程项目中得到广泛应用.获得满意的平差结果的前提条件为:①高质量的基线数据;②约束GNSS控制网的已知点精度足够高,使得GNSS控制网的整体精度不受已知点约束而有明显改变;③优化的平差方案;④科学严密的平差模型.通过对某项目GNSS控制网的布设进行优化设计,并利用不同软件对观测数据进行处理分析...     

结构-功能耦合下的城市水系连通方案两阶段优化

传统水系连通方案编制主要以水系结构为主导,忽略了连通后对水系功能的影响,本文在进行城市水系布局时,将水系连通形状和连通功能两部分纳为一体来制定水系连通方案。基于中心性评价方法,提出河段重要性计算方法来定量刻画河段重要性;借助隶属度函数建立连通功能及其表征参数的函数关系,据此量化水系连通功能效果;以河网连通功能达标率和水系连通性满足度为优选目标,建立结构-功能耦合下的水系连通方案两阶段优化模型,优选最佳闸门联合调度方案。以清潩河许昌段为实例,优化原河网及不同水系连通情景的连通性。研究表明：经过优化后,原河网清潩河水系连通性总体较好,但护城河附近和饮马河的连通性较差;连通护城河和清泥河、连通饮马河和小洪河能极大地提升护城河附近和饮马河的水系连通性。     

Shape optimization of two-dimensional cavitators in supercavitating flows, using NSGA II algorithm

The reduction of energy consumption of high speed submersible bodies is an important challenge in hydrodynamic researches. In this paper, shape optimization of two-dimensional cavitators in supercavitating flows is studied. A two dimensional supercavitation potential flow passes a symmetric two dimensional cavitator, which is placed perpendicular to the flow in a channel of infinite length and immediately a cavity is formed behind the cavitator. This is because of the generation of a gas or vapor cavity between the body and the surrounding liquid due to the change in a high speed flow direction passing the cavitator. Drag force acting on this supercavitating body dictates the thrust requirements for the propulsion system, to maintain a required cavity at the operating speed. Therefore, any reduction in the drag force, by modifying the shape of the cavitator, will lead to decrease this force. This study concentrates on the optimization of two dimensional cavitators in order to decrease drag coefficient for a specified after body length and velocity in a potential flow. To achieve this goal a multi-objective optimization problem is defined to optimize cavitator shapes in supercavitating flow. The so-called NSGA II (Non-dominated Sorting Genetic Algorithm) algorithm is used as an optimization method. Design parameters and constraints are obtained according to supercavitating flow characteristics and cavitator modeling and objective functions are generated using Linear Regression Method. The obtained results are compared with other classic optimization methods, like the weighted sum method, for validation.     

支持向量机在海洋随机资料分析中的应用

在随机海洋资料的分析中,需要从大量的实际数据中提取出有用的信息来建立或检验各种海洋理论模型,因此我们要正确运用适当的手段来分析处理各种实际数据。文中简要介绍了数据挖掘中一项新的技术支持向量机,着重介绍了最优化问题的求解算法,以及如何应用于海洋资料的分析处理。     

一种两步抗差估计的设计及其解算

抗差估计的关键是选择适当的权函数和合理的调制因子,针对这两个重要问题,在研究当前调制因子取值方法的基础之上,提出了可动性调制因子这一新概念,并基于可动性调制因子、IGG方案权函数,设计了两步抗差估计。两步抗差估计解决了抗差估计中传统的调制因子、方差因子、初值三者取值时存在的一系列问题,尤其当三者取值不能协调配制时出现的秩亏问题,从而使抗差估计方法更具有实际意义和广泛意义。     

基于GPS和水准数据的微粒群算法联合反演祁连山北缘断裂三维滑动速率

将微粒群算法与位错理论模型相结合,采用中国地壳运动观测网络提供的青藏高原地区2001~2004年GPS测量数据和2000~2006年水准测量数据,通过常规定权和附有相对权比的方法对祁连山北缘断裂的三维滑动速率进行联合反演,并与蚁群算法反演结果进行对比。结果表明,微粒群算法收敛速度快、稳定性高,结合经典位错理论模型,是一种可以有效求解断层三维滑动速率反演问题的优化算法,在大地测量反演领域极具应用潜力。