常用通讯天线直击雷防护分析

从无线电通讯的原理和特点出发,结合多年防雷工程的施工经验,较系统地介绍了通讯天线直击雷防护的原理、避雷针的设计原则和设计方法以及避雷针的加工、架设方法和施工中的注意事项。     

泾阳4.8级地震前后泾阳地震台形变观测资料的异常分析

分析了泾阳地震台跨断层短水准及流动形变观测资料在 1998年 1月 5日泾阳MS4 .8地震前后的异常变化 .结果表明 ,该次地震前后泾阳台的形变资料出现了明显的短期异常及震后效应 .     

地震前兆数据传输与处理系统的建立

本文从地震前兆数据的传输、报文处理到进入数据库角度出发,介绍了在Ｗｉｎｄｏｗｓ环境下,应用Ｖｉｓｕａｌ Ｂａｓｉｃ、Ｆｏｘｐｒｏ数据库语言和计算机网络技术,实现地震前兆数据的多途径传输;完成报文分检与检错;报文的电报码转换为真实值及追加中等功能。并对建立的“地震前兆数据传输与处理系统”的系统技术思路、功能和特色做了一定介绍。     

Correcting the errors from variable sea salt retention and water of hydration in loss on ignition analysis: Implications for studies of estuarine and coastal waters

The standard technique of determining the concentrations of total suspended solids (TSSs), particulate inorganic matter (PIM), and particulate organic matter (POM) by filtration with glass fiber filters is subject to an error or bias from sea salt plus water of hydration retention, when applied to saline waters. The sea salt plus water of hydration retention by the filters occurs even after washing the filter with 300 ml of deionized water, a greater volume than any wash recommended in the literature. We determined that the mass retention on a glass fiber filter, at a given salinity, is essentially constant, no matter the volume of seawater passed through the filter. We also determined that the sea salt plus water of hydration retention on glass fiber filters is directly proportional to the salinity of the seawater filtered. Sea salt plus water of hydration retention causes an overestimate of TSS; sea salt retention causes an overestimate of PIM; volatilization of water of hydration causes an overestimate of POM. Thus a correction curve is required for sea salt and water of hydration errors in the determination of TSS and PIM. Corrected POM comes from the difference between the two. Also, filter blanks (procedural control filters), run with deionized (DI) water rather than the seawater sample, are required to correct for possible filter mass loss during the analysis. We demonstrate correction curves for sea salt plus water of hydration retention for Whatman GF/F filters, 47 mm diameter, utilizing the methods of the APHA Manual, Standard Methods for the Examination of Water and Wastewater. Application of other glass fiber filter types or an analytical technique differing significantly from that employed here requires a different correction curve for retention of sea salt and water of hydration. These methods can be used to reanalyze older data on PIM, POM, and TSS.We apply these corrections to PIM and POM data from the northern Gulf of Mexico and examine the interactions of these filter corrections with corrections for structural water volatilization from suspended clay minerals in the determinations of PIM and POM. We analyze published data on PIM and POM determinations and their application to remote sensing. We conclude that sea salt and water of hydration retention on filters has an adverse effect on remote-sensing algorithms inverting radiance reflectance to estimate concentrations of suspended matter.     

基于Eclipse的移动客户端地图浏览软件开发

本文在对移动客户端地图浏览软件研究调研的基础上,分析了现有移动手持设备地图浏览软件的功能及其开发技术,总结了Eclipse和Mobile SVG在移动设备上开发和应用的优势,并提出如何运用Eclipse、EclipseME及SVG Tiny构建3G手机上的地图应用。本文将J2ME、SVG技术融合到移动GIS中,以Eclipse为开发平台,SVG为地图表达语言,用XML描述属性信息,调研了手机客户端地图浏览器的基本功能,且在3G手机中实现了地图的浏览与简单的查询,并用模拟索引机制和序列化方法实现本地数据的有效管理。此方法对今后的移动地图服务有着广阔的应用前景。     

利用不规则载荷模型分析马家岭流动水准异常

通过环境调查等手段,收集整理马家岭水准观测场地周边环境变化参数及岩土力学参数,运用不规则二维载荷模型计算荷载引起的水准高差变化。结果显示,霍山大峡谷漂流场地停车场的建设对马家岭水准观测有一定影响,影响量约为0.77mm,与实际观测高差0.70mm接近,研究结果从定量模拟的角度证实了马家岭流动水准异常为环境荷载变化引起的地面高差变化。     

基于PDA的移动GIS开发

随着人们生活水平的不断提高,PDA以其体积小、能耗低、功能强、易开发等优势已经进入平民化阶段.目前,基于PDA的移动GIS开发和应用已成为越来越多GIS二次开发商和用户关注的焦点.本文首先介绍了PDA的定义、分类和主流操作系统,然后分析了移动GIS的特点,并对比了几种可视化开发语言,最后以一个实例来阐述基于PDA的移动GIS开发.     

The future that may (or may not) come: How framing changes responses to uncertainty in climate change communications

Communicating possible effects of climate change inevitably involves uncertainty. Because people are generally averse to uncertainty, this activity has the potential to undermine effective action more than stimulate it. The present research considered how framing climate change predictions differently might moderate the tendency for uncertainty to undermine individual action. Two studies (Ns = 88 and 120) show that higher uncertainty combined with a negative frame (highlighting possible losses) decreased individual intentions to behave environmentally. However when higher uncertainty was combined with a positive frame (highlighting the possibility of losses not materializing) this produced stronger intentions to act. Study 2 revealed that these effects of uncertainty were mediated through feelings of efficacy. These results suggest that uncertainty is not an inevitable barrier to action, provided communicators frame climate change messages in ways that trigger caution in the face of uncertainty.     

2019年丰南4.5级地震前后岩石圈磁场水平矢量动态演化特征

基于唐山及周边地区2018年4月—2020年9月连续6期的流动地磁观测资料,经过数据处理获得5期岩石圈磁场半年尺度的时空变化数据,再结合2019年12月5日丰南4.5级地震对震中附近岩石圈水平矢量时空演化特征进行分析。结果表明: ①在岩石圈磁场水平矢量动态演化过程中,丰南地震震中附近岩石圈磁场水平矢量异常出现在震前一年时期,且随着时间推移,岩石圈磁场水平矢量弱变区在空间上具有由东向西发展的演变过程。②丰南地震震中区域水平矢量模值在地震前后出现先减小后增大的反向变化,震前半年水平矢量模值最小,丰南地震发生于水平矢量模值反向增大的过程中。③根据亚失稳理论与岩石圈磁场水平矢量变化关系,在多期岩石圈磁场水平矢量存在方向变化和弱变的区域寻找潜在的异常区,再结合异常区水平矢量模值的动态演化,或许可以作为一种识别震前震磁前兆异常信息的方法。     

医学影像存储和通讯系统

本文叙述了PACS的发展和特点:DICOM3.0的现状;PACS的通讯和存储技术;并对PACS的效益进行评价和展望。