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101.
Wagner José Barreto Ieda Scarminio Maria Cristina Solci Dílson Norio Ishikawa Melissa Tiemi Ogasawara Sônia Naomi Nomi Sônia Regina Giancoli Barreto 《洁净——土壤、空气、水》2007,35(3):239-245
Seventeen physical and chemical parameters were obtained from a hydroelectric reservoir located in a tropical region in the south of Brazil. Multivariate Principal Component Analysis (PCA) and Hierarchical Group Analysis (HGA) were used to identify the parameters discriminating the origin of water from the Tibagi and the Primeiro de Maio River, after it has passed the mixing region. The study was conducted during the dry and rainy seasons in July 2002 and February 2003 at three depths and three sampling sites located 0, 5, and 10 km away from the mixing region. The statistical methods showed to be appropriate for identifying the contribution of each tributary in the water mixing site of a complex water system. The most important discriminating parameter was the absorbance relation A(253 nm)/A(203 nm), followed by the concentrations of Fe(III), Mn(III), and Ni(II). An anthropogenic interference was found in the reservoir due to high Ni(II) and orthophosphate concentrations caused by a nearby town sewage discharge. The interference was more important during the dry periods due to the lower dispersion of the pollutants. Urgent initiatives should be taken from the state government to build treatment stations for the wastewater of the small cities around the Capivara hydroelectric reservoir to prevent the drinking water quality from deteriorating. 相似文献
102.
运用现代构造地质研究方法,对蔚县矿区构造特征及断裂构造发育规律进行了研究。并揭示了矿区构造成因机制及演化历史。 相似文献
103.
Robustness analysis of geodetic horizontal networks 总被引:2,自引:1,他引:2
104.
105.
运用最大树法模糊聚类分析,将台湾地区1936年至1989年间的35个地震事件分成了三类6型,并运用聚类结果对1990年至2000年的11个地震事件进行检验,得出了比较合理的检验结果,最后用聚类结果对台湾地区2001年的地震趋势进行了预测,得出了与其它手段一致的预报结果. 相似文献
106.
湖南省郴州市在经济发展中具备资源丰富,邻近发达的珠江三角洲地区,区位优势等众多有利条件,但同时也存在区内交通不便,经济基础薄弱等一些不利因素。为抓住所面临的大好机遇,作者提出了加快该区基础设施建设、软环境建设、重视科技、加强环境保护和发展旅游等5项对策,并提出了该区经济发展可持续模式;即产业结构优化模式和点轴开发空间布局,最后提出了进一步完善布局的建议。 相似文献
107.
This paper points to the need for seismic risk and vulnerability assessment of infrastructure systems, most notably tall structures and coastal facilities, in Kuwait and other Arabian Gulf countries. Building codes in the region currently lack seismic provisions, despite evidence of a potential threat from large-magnitude earthquakes originating from the southern part of the Zagros fold belt. The historical record of Iranian earthquakes that may have caused significant ground motion in the Gulf region is examined, as are reports of coastal damage from tsunamis. Various specific tasks, expected to constitute research priorities of a Joint Center for Risk Research, a cooperative research program involving Princeton and Kuwait Universities, are outlined. 相似文献
108.
Groundwater contamination: risk management and assessment for landfills in Mar del Plata, Argentina 总被引:3,自引:0,他引:3
This study presents a program for risk management in the contamination of groundwater resulting from leachate in landfills
at Mar del Plata (Argentina). The program includes prediction, prevention, monitory observation and mitigation as actions
that must be taken prior to, during, and after contamination occurs. This routine aids in the identification of weak points
and failures of the program for those who are in charge of making decisions, and will allow better use of limited financial
and technical resources based on planning, thus minimizing disconnected determinations.
Results of the prediction stage were confirmed through monitoring. The presence of a plume of contamination more than 100 m
from the landfill was shown, thus proving that implementation of a monitoring plan to follow the development of the contaminated
plume must be implemented, particularly in populated areas which depend on residential wells for their water supply.
Received: 8 May 2000 · Accepted: 14 August 2000 相似文献
109.
计算机仿真模型的灵敏度分析,是仿真建模中的重要研究内容,对实际系统的建立和优化具有重要意义。本文主要研究了在用蒙特卡洛方法仿真随机系统时,其仿真模型(输出)的灵敏度(导数、梯度、Hessian矩阵等),对系统性能函数和灵敏度的参数估计进行了探讨,并结合实际应用系统,对结论进行了分析比较。 相似文献
110.