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1.
Assessing the health of and maintaining civil infrastructure has been an increased concern in the wake of natural disasters such as Hurricane Katrina in 2005 and the summer 2007 flood events in the UK. The variability of properties within geotechnical systems makes predictions of soil behavior extremely difficult, especially when soil models are not calibrated with field-measured performance. Unfortunately the current state of the art in geotechnical system health assessment is either based on very expensive monitoring systems for real-time information or on periodic measurement of ground surface displacements. Accordingly, a need has arisen for a system capable of in situ, real-time monitoring of levees, embankments, and other earthen structures. The work presented herein highlights the development of novel, affordable sensing technologies for use in a framework to monitor, manage and ensure the safety of geotechnical infrastructure. MEMS (micro-electro-mechanical systems)-based in-place inclinometer system, Measurand’s ShapeAccelArray (SAA), is now established as a sensing tool for simultaneous measurement of 3D soil acceleration and 3D ground deformation up to a depth of one hundred meters, with an accuracy of ±1.5 mm per 30 m. Each sensor array is connected to a wireless sensor node to enable real-time monitoring as well as remote sensor configuration. This system is now being further developed to include digitally integrated pore pressure measurement in the form of vibrating wire piezometers equipped with microprocessors (called SAAPs). The SAAPs are able to convert vibrating wire data to digital data downhole, and they integrate easily into the SAA system. In situ testing was conducted in a levee in England subjected to significant tidal loading (up to 6 m of fluctuation during spring tides) through collaboration with the European Union’s UrbanFlood project. In addition to the SAAs and SAAPs installed in three sections of the levee, the site was also instrumented with other sensors from Alert Solutions and TenCate, providing values for comparison. The likelihood of this levee to experience deformation and the density of instrumentation installed in the bank made this the ideal location to test the new SAAP system. The additional insight into subsurface behavior provided by the SAAPs is integral in the development of a comprehensive system for monitoring and management of civil infrastructure. The preliminary testing indicates the suitability of this new multi-parameter system for inclusion in a multi-scale monitoring and health assessment framework, which will be implemented in New Orleans, LA in 2012.  相似文献   

2.
地勘单位要吸引和留住人才,就要在事业、感情、待遇留人上下功夫.即营造鼓励人才干成事业、帮助人才干好事业、创造施展才华的社会氛围和环境;用来自领导的关心爱护之情,同事的团结友爱之情来拴住人心;为人才提供与其创新能力和贡献相适应的物质待遇,使人才充分享有实现自身价值的自豪感、贡献社会的成就感、得到社会承认的荣誉感.  相似文献   

3.
基岩裂隙水探寻是一项意义重大的研究课题,富水优势断裂的确定是其中的关键。文章详细论述了运用层次分析法寻找富水优势断裂并进行分级的实施方法。这一方法的实施可归纳为"两个前题条件,五个分析步骤,一个结果判断",两个前题条件为富水性功能分类和构建优势指标体系,五个分析步骤为构建层次分析结构模型、构造判断矩阵、层次单排序及其一致性检验、层次总排序、对象层权重总排序;一个结果判断为利用层次分析的结果进行断裂富水性分级,从而最终确定出富水优势断裂。此法为富水优势断裂的定量化评价提供了一种简洁、实用的新方法。   相似文献   

4.
我国直接为农业服务的磷、硫、钾矿资源总体形势不容乐观。针对各自资源特点,应采取不同的发展战略:磷——立足国内,有进有出,南出北进;硫——立足国内,适当进口,调整结构,必要储备;钾——稳定进口,国外开发,国内开发,国内找矿,四位一体,分三步走。为此建议:将磷、硫、钾纳入战略性矿产资源的范畴进行管理和规划;强化地勘队伍,加大找矿力度;增加投入,寻求新的突破;加大“走出去”的步伐;规范进出口秩序;国家在更高的层面进行宏观调控;拓宽为农业服务的新领域。  相似文献   

5.
《International Geology Review》2012,54(11):1042-1050
Minerals of the stibnite-antimonselite series, in close association with tiemannite, clausthalite, kullerudite, Se-bearing stibioluzonite, native gold, quartz, and barite, were discovered in Cambrian stratabound gold deposits at La'erma and Qiongmo, western Qinling, China. Based on S/(S + Se) ratios of microprobe analyses, the binary stibnite-antimonselite system is divided into four series: stibnite, Se-stibnite, S-antimonselite, and antimonselite. Micro-hardness of the stibnite series (Sb = 58.47 to 72.99 wt%, S = 11.86 to 28.76, and Se = 0.00 to 29.12) and the antimonselite series (Sb = 48.94 to 59.13 wt%, Se = 29.20 to 46.86, S = 1.99 to 11.43) is 101.26 and 103 kg/mm2, respectively. Representative reflectivities of the four series are (470 nm) Rg'= 42.62 to 47.62%, Rp' = 30.83 to 40.55%; (550 nm) Rg' = 41.84 to 46.75%, Rp'= 31.48 to 38.85%; (590 nm) Rg' = 42.25 to 46.63%, Rp' = 30.73 to 39.46%; (650 nm) Rg' = 43.30 to 46.48%, Rp' = 30.01 to 41.56%. Cell parameters obtained from two stibnite samples (containing 3 to 5% Se) are a = 1.1209 to 1.1212 nm, b = 1.1299 to 1.1303 nm, c = 0.3847 to 0.3849 nm; and those of S-antimonselite and antimonselite are a = 1.1591 to 1.1593 nm, b = 1.1724 to 1.1747 nm, and c = 0.3941 to 0.3984 nm.  相似文献   

6.
In this paper, the sequential extraction procedure was used for the selection of fractions of lead in seven stages corresponding to lead exchangeable, lead bounded to carbonates, to manganese oxides, to organic matters, to amorphous iron, and lead associated to crystallized iron, and to residuals. The vertical distributions of lead species were carried out in the soils related to good agriculture progress (GAP) of Chinese medical materials of Ligusticum chuanxiong Hort in Dujiangyan city and Wenchuan County, Sichuan Province. Based on those researches, it is found that the plant of Glycine Max (L.) Merr. has the character of lead enrichment and sorption, which is not reported in the literature. Using Glycine Max (L.) Merr. alternate planting with Ligusticum chuanxiong Hort is a valuable recommended in order to produce a high quality Chinese medical materials in order to eliminate the barrier on the beyond the lead limit for the import and export of Ligusticum chuanxiong Hort.  相似文献   

7.
三江地区含锡花岗岩Rb—Sr等时线年龄   总被引:7,自引:1,他引:7  
通过含锡花岗岩全岩Rb-Sr等时线年龄研究,哀牢山-金沙江锡矿带的含锡花岗岩形成于燕山中晚期(133~80Ma);临沧-左贡锡矿带的年龄范围648~370Ma,相当于徵江期到海西期;潞西-腾冲锡矿带,属于燕山晚期到喜山期(105~51Ma)。  相似文献   

8.
Landslide risk: some issues that determine societal acceptance   总被引:2,自引:1,他引:1  
This paper illustrates approaches to landslide risk acceptance in various parts of the world in the context of the willingness to accept that risk, the willingness to pay to reduce the risk, and the willingness to alter the environment in the process. These factors are interlinked using the ternary ??willingness diagram?? which is also used to demonstrate how such willingness may change over time and to compare a range of generic approaches to landslide remediation as well as different conceptual approaches to landslide risk management. The willingness construct is intended to provide a readily understood framework for infrastructure owners and operators, amongst others, to understand how their approach to risk management compares with those in other regions, countries and contexts. Issues relevant to the response of society and groups of individuals to landslide risk, its acceptance and management include cultural factors, regulation and planning, budgetary constraints, vehicular vulnerability, and the often limited size of the event footprint compared to the vulnerability shadow that is cast are also discussed.  相似文献   

9.
以云南小江典型岩溶流域为例,在GIS支持下,通过选择评价因子和建立评价模型对岩溶区的土地整理进行了生态评价。结果表明: 流域生态评价分值较高的土地面积较少,而生态评价分值较低的土地面积较大。分值在80~ 100的土地整理主要任务是在保护生态环境质量和耕地数量的前提下,加快流域经济结构的调整,提高土地利用的经济效益;分值在70~ 80的土地整理主要任务是耕地数量保护和质量保护并重,提高土地的生产能力,提高经济效益,同时防止水土流失及化肥、农药施用对地下水造成的非点源污染; 分值在60~ 70的土地整理主要任务是着重于生态环境的保护和重建以及立体农业的综合开发; 分值在60以下的土地整理主要任务是土地石漠化的治理。   相似文献   

10.
Based on the questionnaire survey, this paper analyzes China’s public perception of climate change in terms of several influence factors and some empirical findings are obtained. We find that some respondents are willing to take individual actions to address climate change, and they pay more attention to climate change or approve that climate change does harm to residents and society; meanwhile, they tend to have confidence in the government to deal with climate change or believe that fiscal and taxation policies are the effective policy measures. However, there are also other respondents unwilling to take actions and argue that climate change proves the natural consequences. Thus, in order to motivate the public to take actions, the paper suggests that the government should widespreadly disseminate relevant knowledge about climate change to the public and guide the work to address climate change and adopt proper fiscal and taxation policies.  相似文献   

11.
Mangrove forest stores large organic carbon stocks in a setting that is highly vulnerable to climate change and direct anthropogenic influences. As such there is a need to elucidate the causes and consequences of land use change on these ecosystems that have high value in terms of ecosystem services. We examine the areal pattern of land types in a coastal region located in southern Iran over a period of 14 years to predict future loss and gain in land types to the year 2025. We applied a CA–Markov model to simulate and predict mangrove forest change. Landsat satellite images from 2000 to 2014 were used to analyze the land cover changes between soil, open water and mangroves. Major changes during this period were observed in soil and water which could be attributed to rising sea level. Furthermore, the mangrove area in the more seaward position was converted to open water due to sea-level rise. A cellular automata model was then used to predict the land cover changes that would occur by the year 2025. Results demonstrated that approximately 21 ha of mangrove area will be converted to open water, while mangroves are projected to expand by approximately 28 ha in landward direction. These changes need to be delineated to better inform precise mitigation and adaptation measures.  相似文献   

12.
朱明善 《沉积学报》1988,6(3):78-88
本文据东海五口探井的559个碎屑矿物样资料,用主要重矿物的含量及其组合特征编绘了含量变化图,试图进行分层比较。位于西湖凹陷的平湖一井和玉泉1井重矿组合特征可比性较好;龙井2井三潭组以下与上两井缺少可比特点;灵峰1井除东海群外,其余地层与上列3井相比,差异是大的。  相似文献   

13.
湖南省探矿权、采矿权市场现状与发展对策   总被引:1,自引:0,他引:1  
探矿权、采矿权市场是社会主义市场经济的重要组成部分.培育和规范探矿权、采矿权市场不仅是实现矿产资源利用方式和管理方式转变的根本途径,更是推动矿业经济全面开放。走向健康有序发展的强大动力.湖南省的探矿权、采矿权市场还不发育,与我国市场体制的发展进程和其他各类市场的建设进程相比,很难适应入世的需要.在对湖南省探矿权、采矿权市场现状进行深入分析的基础上,提出了解放思想、整顿秩序、明确政策、加强勘探。严格规划、加强领导等项措施来培育和规范我省探矿权、采矿权市场.  相似文献   

14.
封闭体系有机质与有机碳氢氮恢复动力学研究   总被引:3,自引:0,他引:3  
在封闭体系的条件下,对典型的Ⅰ、Ⅱ、Ⅲ型干酪根在热演化过程中的损失进行生烃动力学研究,获得了Ⅰ、Ⅱ、Ⅲ型干酪根的总量、有机碳、氢以及氮质量损失动力学参数。用Kinetics软件计算了封闭体系干酪根有机碳丰度、氢碳原子比和氮碳原子比的恢复系数。认为在对高成熟—过成熟干酪根进行生烃评价时,Ⅰ、Ⅲ型干酪根残余有机碳丰度需要进行恢复,而Ⅱ型干酪根残余有机碳丰度不需要恢复。三种类型干酪根的氢碳原子比均需要进行恢复。  相似文献   

15.
Nutrient loading to estuaries with heavily populated watersheds can have profound ecological consequences. In evaluating policy options for managing nitrogen (N), it is helpful to understand current and historic spatial loading patterns to the system. We modeled N inputs to Narragansett Bay from 1850 to 2000, using data on population, human waste disposal, livestock, fertilizer, and atmospheric deposition. We found that total N loading to the bay increased 250% from 1850 to 2000, and 80% from 1900 to 2000. Loading to the upper bay increased far more than that to the lower bay, and the most important source shifted from non-point animal waste to human waste concentrated at sewage treatment facilities. We also modeled future N loads in 2015 under four management scenarios. Planned improvements in sewage treatment would reduce N loads 9% below business-as-usual, to the 1990 loading rate. Greater reductions, to circa 1900 rates of loading, may be possible.  相似文献   

16.
文章以金川和红原两组泥炭纤维素Δδ13C时间序列值的反向变化来指示西太平洋副热带高压活动变化.结果表明,在过去5000年中,西太平洋副热带高压的活动可分为4个阶段,即西太平洋副热带高压位置在2800~2200B.C.期间持续偏北,2200~600B.C.期间持续偏南,600B.C.~1200A.D.期间在北进与南移之间频繁波动,以及1200~1900A.D.期间再次持续偏北,它们导致降雨量在中国大陆上不同的分布.从约1900A.D.起西太平洋副热带高压的活动似乎又开始一个新的偏南阶段,值得进一步加强研究.  相似文献   

17.
湿陷性黄土增湿和减湿效应的探讨   总被引:1,自引:0,他引:1  
湿陷性黄土的湿陷性不是一成不变的。土中含水率的变化产生的增湿和减湿效应,对黄土湿陷性影响很大。进行黄土湿陷性评价时,应注意以动态的观点和方法综合分析、预测增湿和减湿效应的不利影响,以便采取有效的处理措施,消除工程事故隐患。  相似文献   

18.
中下扬子区二叠系露头层序地层研究   总被引:15,自引:1,他引:15  
按新近国际年代地层划分方案(ICS,2000),下扬子区二叠纪地层自下向上分为3统,9阶和相对应的华南传统6阶划分。二叠系从阿瑟尔阶至长兴阶(44Ma)共划分出14个三级层序,每个三级层序平均时限约为3.14Ma,其中“紫松阶”)相当阿瑟尔+2/3萨克马尔阶)1个(船山组中上部)、“隆林阶、(相当1/3萨克马尔阶+阿丁斯克阶)2个(分别对应船山组上部和梁山组或镇江组)、“栖霞阶”(相当库班甘德阶+1/3罗德阶)3个(栖霞组),“茅口阶”(相当于2/3罗德阶+沃德阶+卡皮丹阶)4个(孤峰组,茅口组,堰桥组,银屏组和武穴组),吴家坪阶2个(龙潭组或吴家坪组),长兴阶2个(长兴组或大隆组);共归并为4个层序组(sequence set)。  相似文献   

19.
高分辨率地震采集数据是构造解释和砂体预测的基础资料,其保真程度的高低直接影响到小构造和砂体预测的准确性。震源的激发、波的传播、检波器的接收和仪器记录各个环节对地震信息的保真度都有影响,地震采集每个环节的分析、研究对提高地震信息的保真度具有重要意义。  相似文献   

20.
《Applied Geochemistry》1998,13(4):415-420
The European Communities Bureau of Reference (BCR) and Chunguo sequential extraction procedures were employed to evaluate the retention of U and As by a soil contaminated with low level radioactive waste. Modifications were made to both procedures to optimize the measurement of soil and extractant samples using epithermal neutron activation analysis. Based on the BCR procedure, approximately 20% of the U appeared to be bound to the carbonate fraction, 10% to the mineral oxide fraction and 20% to the organic fraction. In the case of As, the majority was strongly bound in the residue fraction. The results obtained with the Chunguo procedure supported these conclusions to some extent, in that the majority of the U and As was found to be strongly bound to the soil in a manner consistent with its presence in the residue fraction.  相似文献   

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