路基边桩放样方法的深入探讨

逐渐趋近法是路基边桩放样的主要方法,但试算次数不确定,为了实现加速收敛,采用了Au-toCAD仿真模拟实地路基边桩放样的过程,对各种情况的收敛速度进行了比较,揭示了各种办法的优劣,并对逐渐趋近法放样路基边桩的步骤进行了总结。     

Seafloor sediment classification based on multibeam sonar data

The multibeam sonars can provide hydrographic quality depth data as well as hold the potential to provide calibrated measurements of the seafloor acoustic backscattering strength. There has been much interest in utilizing backscatters and images from multibeam sonar for seabed type identification and most results are obtained. This paper has presented a focused review of several main methods and recent developments of seafloor classification utilizing multibeam sonar data or/and images. These are including the power spectral analysis methods, the texture analysis, traditional Bayesian classification theory and the most active neural network approaches.     

沈阳地铁精密导线控制网成果分析

针对沈阳市地铁新、旧线路横跨两个坐标系统问题,笔者对同一套边长观测数据分别进行北京54、西安80两套坐标系统边长改化、平差,均取得良好成果,使地铁新旧控制成果可在54、80系统间随意比对,为地铁的旧点校正、安全贯通奠定了基础。     

基于3维激光扫描技术的滑坡体地形图制作研究

采用3维激光扫描技术快速采集滑坡体地形点云信息,并提取滑坡体微地貌信息,为滑坡监测提供基础技术支持。3维激光扫描技术的数据处理主要包括外业数据采集、点云数据配准、地貌数据获取与非地貌点云数据过滤、地形图生成等过程,并着重介绍其工作原理与处理方法。采用3维激光扫描技术能够高效准确实时的监测地质灾害,对预防灾害的发生提供了决策作用。     

A study on the temporal and spatial characteristics of droughts following earthquakes

According to the ＂jacking-up＂ theory, which relates the cause of earthquakes to outer core convection ascension bodies, the crust will gradually recover after an earthquake. In such cases, the crust is stretched, the underground temperature is reduced, precipitation decreases, and drought occurs. In this paper, precipitation is compared with ground temperature and seismic data to determine the spatial and temporal relationship between earthquakes and subsequent droughts. Our objective is to develop a new method of drought prediction. With a few exceptions in location, the analysis of the first drought to occur after the Ms 〉 7 earthquakes in mainland China and the adjacent areas since 1950 shows that droughts tended to occur in regions near earthquake epicenters and in the eastern regions of the epicenters at the same latitude within six months after the earthquakes. In addition, and the differences between the starting time of the earthquakes and the droughts nearly share the same probability of 0 to 6 months. After careful analysis of 34 Ms 〉 6.5 earthquakes occurring in western China from 1980 to 2011, we determined that a second drought tends to occur approximately six months following the first drought, indicating a quasi-half-year period. Moreover, the duration of the quasi-half-year fluctuation increases with the magnitude of earthquake, at approximately 2.5 years for Ms 6.5 earthquake and approximately 5 years for Ms 8 earthquake.     

Sensitivity of disease cluster detection to spatial scales: an analysis with the spatial scan statistic method

ABSTRACT

The spatial scan statistic method has been widely used for detecting disease clusters. Its results may be affected by scales, including the aggregation level of the input data and the population threshold used in the detection. Previous studies offered inconsistent findings, and few had considered both types of scales at the same time. Using 24 simulated datasets and two real disease datasets, we investigated the method’s sensitivity to the two types of scales. We aggregated the individual-level data into areal units of three levels, including county, town, and a 900 m grid. We detected clusters with three population thresholds, including 10%, 25%, and 50%. We used two measurements, distance between cluster centres and the Jaccard index, to quantify the consistency of clusters detected with different scale settings. We find: (1) the method is not greatly sensitive to the data aggregation level when the cluster is strong and in a place with high population density; (2) the method’s sensitivity to the population threshold is determined by the actual size of the true cluster; and (3) a regular grid with fine resolution is advantageous over the subjectively defined areal units. The process and findings may have broader meanings to similar spatial analyses.     

湖北省气象局网络安全系统设计

通过介绍湖北省气象局网络安全需求，分析了现有网络系统存在的安全弱点，利用目前主要的网络安全防御技术，设计了一个整体的网络安全系统，为湖北省气象局网络安全系统的后续建设和实施提供了具体的思路。     

基于Windows下溢出漏洞扫描技术的网络渗透分析与实现

网络渗透技术在信息安全领域里扮演着重要的角色。漏洞扫描技术是网络渗透最基本的技术之一，对目前流行的几种网络渗透技术进行了介绍，对漏洞扫描技术的分类和实现进行了分析，对Windows下的溢出漏洞扫描方法进行了研究，并就WinE000的PNP溢出漏洞（MS05-039）的扫描进行分析和代码实现。     

车载激光扫描数据的道路边界线提取方法

鉴于城市道路两侧具有路坎这一特点,结合车载激光扫描系统的轨迹数据将整体点云进行分块处理,从每一块点云中截取部分数据投影到相应的截面上;然后,对获取的截面数据进行分割处理提取伪扫描线,根据路坎的坡度以及高差特点从伪扫描线中识别出路坎点;最后,利用三次样条插值的方法对提取的道路路坎点进行插值处理,得到道路边界线。实验证明了该方法的可行性和有效性。     

邯邢地区京广铁路以东隐伏富铁矿资源潜力浅析

“邯邢式”铁矿是产于以奥陶系为主的灰岩和中性偏碱性为主的岩体形成的接触交代型富铁矿。通过深入研究,认为京广铁路以东获得的6个航磁异常,具有寻找隐伏的“邯邢式”富铁矿的潜力,应加大对该区寻找隐伏磁铁矿资源的力度。