The dynamics of natural pipe hydrological behaviour in blanket peat

Natural soil pipes are found in peatlands, but little is known about their hydrological role. This paper presents the most complete set of pipe discharge data to date from a deep blanket peatland in Northern England. In a 17.4‐ha catchment, we identified 24 perennially flowing and 60 ephemerally flowing pipe outlets. Eight pipe outlets along with the catchment outlet were continuously gauged over an 18‐month period. The pipes in the catchment were estimated to produce around 13.7% of annual streamflow, with individual pipes often producing large peak flows (maximum peak of 3.8 l s^?1). Almost all pipes, whether ephemerally or perennially flowing, shallow or deep (outlets > 1 m below the peat surface), showed increased discharge within a mean of 3 h after rainfall commencement and were dominated by stormflow, indicating good connectivity between the peatland surface and the pipes. However, almost all pipes had a longer period between the hydrograph peak and the return to base flow compared with the stream (mean of 23.9 h for pipes, 19.7 h for stream). As a result, the proportion of streamflow produced by the pipes at any given time increased at low flows and formed the most important component of stream discharge for the lowest 10% of flows. Thus, a small number of perennially flowing pipes became more important to the stream system under low‐flow conditions and probably received water via matrix flow during periods between storms. Given the importance of pipes to streamflow in blanket peatlands, further research is required into their wider role in influencing stream water chemistry, water temperature and fluvial carbon fluxes, as well as their role in altering local hydrochemical cycling within the peat mass itself. Enhanced piping within peatlands caused by environmental change may lead to changes in the streamflow regime with larger low flows and more prolonged drainage of the peat. Copyright © 2012 John Wiley & Sons, Ltd.     

基于概率完备震级评估首都圈地震台网检测能力

完备震级是评估区域地震台网检测能力的一个定量指标,本文采用能反映区域地震台网检测能力的时空分布细节特征的概率完备震级分析方法,对首都圈地震台网的检测能力进行了研究,通过对首都圈2002-2009共8年的地震目录和台站资料的分析处理,得到了首都圈地震台网的完备震级时空分布,据此对台网的检测能力进行了评估,并结合模拟结果探讨了提升台网检测能力的可能性.结果表明：首都圈地震台网的整体检测能力较强,北京地区的检测能力尤其突出,但部分区域检测能力仍有一定的提升空间;模拟结果表明,在东北、西北、西南等位置增加台站可能有助于进一步提高台网的检测能力.相关研究结果可能对未来首都圈地震台网的优化具有参考意义.     

北京测震台网台基背景噪声特征

利用Welch算法,选取北京市测震台网28个测震台站地震连续波形中不同时段的无震记录,计算其台基噪声功率谱并进行背景噪声特征的统计分析,结果表明:北京市测震台网各台基噪声背景优势频率各有特征,高低频段噪声功率谱曲线差异大。在1~20Hz频段内,北京地区的背景噪声高值区出现在中心城区附近,低值区出现在北部的琉璃庙、密云和南部的上方山等台站,主要受人为噪声影响;在0.008~0.1Hz频段内,北京所有地区差异不大。     

利用防火墙软件实现市、县局用户共享上网

介绍采用W inRoute F irewall软件实现市、县局用户共享上网的方法,使市县局用户既能共享网络资源,又能有效地保障网络安全。     

郑州市城区深部基岩层热储特征分析

通过对郑州市城区深部基岩层热储的岩性、构造、热源及盖层条件分析研究,总结了该区热储特征,并首次提出了断裂循环型带状热储构造网络体系的构思,这对该区今后深部基岩层热储的研究具有一定的参考意义。     

贵州省气象甚高频通信网最佳方案的研究

通过时在贵州山区组建甚高频通信网进行工程设计、方案试验、运行调整，确立了该通信网的最佳方案。所谓最佳方案，即要求该网的复盖率为１００％，中转环节最少、信号稳定可靠，既能进行话传，又能进行数传。目前，在山区组建这样的甚高频通信网及其实现的方法，在我国尚属先例。     

OpenMediaVault存储方案在智能网格预报业务中的应用

为满足智能网格天气预报业务的应用需求,设计并搭建NAS网络存储方案。方案基于Debian Linux操作系统,通过搭建虚拟机环境,使用Open MediaVault软件等技术开发而成。使用该网络存储方案可以将存储设备与服务器彻底分离,集中管理和共享数据,从而释放带宽,提高性能,大大降低存储成本,提高重要天气预报业务系统运行效率。     

Exploring the structure of the U.S. intercity passenger air transportation network: a weighted complex network approach

The U.S. airline network is one of the most advanced transportation infrastructures in the world. It is a complex geospatial structure that sustains a variety of dynamics including commercial, public, and military operations and services. We study the U.S. domestic intercity passenger air transportation network using a weighted complex network methodology, in which vertices represent cities and edges represent intercity airline connections weighted by average daily passenger traffic, non-stop distance, and average one-way fares. We find that U.S. intercity passenger air transportation network is a small-world network accompanied by dissortative mixing patterns and rich-club phenomenon, implying that large degree cities (or hub cities) tend to form high traffic volume interconnections among each other and large degree cities tend to link to a large number of small degree cities. The interhub air connections tend to form interconnected triplets with high traffic volumes, long non-stop distances, and low average one-way fares. The structure of the U.S. airline network reflects the dynamic integration of pre-existing urban and national transportation infrastructure with the competitive business strategies of commercial airlines. In this paper we apply an emerging methodology to representing, analyzing, and modeling the complex interactions associated with the physical and human elements of the important U.S. national air transport and services infrastructure.     

基于SXCORS网络的RTK技术在控制测量中的应用及精度分析

结合工程实例,对基于SXCORS网络的RTK技术在控制测量中与静态GPS、水准测量的数据进行了比较,对其精度进行了分析,得出了在有利条件下该技术的适用性。     

中国陆区S波分型与上地幔地震各向异性

本文利用中国大陆区共8个台站所观测到地震事件的S波数据，采用相关分析的手段以 观测数据重建的技术，进行了S波分裂参数－快慢波延迟时间与快波偏振方向的计算，并分析了S波分裂参数与中国陆区上地幔物质运动的相互关系，研究了结果表明，兰州台下的S波分裂时差最小，北京台下的最大，中国东部地区上地幔运动方向以西北向为主，西部地区以北偏西为优势。