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91.
SARS空间传播模式及其在疫情监控信息系统设计中的应用 总被引:4,自引:0,他引:4
在中国控制SARS(Severe Acute Respiratory Syndrome)疫情扩散与蔓延的大量科学实践活动基础上,从人地系统科学的理论和观点出发,提出了各种致病因子在人地互动过程中转移路径的逻辑模型,进而又提出了控制SARS疫情发展的人地互动逻辑模型。从后一个模型出发,把中国SARS疫情的发展规律归纳为5种传播模式,即异类病毒转移传播模式、家庭和社区接触传播模式、医院和门诊感染传播模式、市内随机扩散传播模式和飞点跳跃跨区传播模式。其中,跨区传播模式的影响最广泛、危害最巨大、控制起来最艰巨、复杂,是建立中国突发公共卫生事件应急机制、增强应急能力需要解决的主要问题和关键内容。为此,作者对中国的疫情控制应急机制及其实现提出了一些具体的看法和建议,包括对现有疫情系统进行技术改造和创新的建议,在全新运作机制和高技术基础上建立应急疫情监测控制信息系统的概念结构等内容。 相似文献
92.
介绍了基于ITU-T协议标准的数字化监视系统的特点、组成及功能,详细论述了系统实现的关键技术,描述了系统在电力设备远程监控中的应用。 相似文献
93.
Zhang Shaoquan Guan JieInsntute of Geophysics SSB Beijing China Beijing Mining Bureau Beijing China 《中国地震研究》1995,(1)
A sophisticated seismological method has been introduced to the study of mining tremors by the Institute of Geophysics,SSB in cooperation with the Beijing Mining Bureau of NCC.Achievements have been obtained in the following areas:modification of the seismic monitoring system,compilation of a software package for analysis of mining tremors,research on the mechanical model for mining tremors,classification of mining tremors and development of an expert system of tremor prediction. 相似文献
94.
Dmitri Rouwet Salvatore Inguaggiato Yuri Taran Nicholas Varley José A. Santiago S. 《Bulletin of Volcanology》2009,71(3):319-335
This study presents baseline data for future geochemical monitoring of the active Tacaná volcano–hydrothermal system (Mexico–Guatemala).
Seven groups of thermal springs, related to a NW/SE-oriented fault scarp cutting the summit area (4,100m a.s.l.), discharge
at the northwest foot of the volcano (1,500–2,000m a.s.l.); another one on the southern ends of Tacaná (La Calera). The near-neutral
(pH from 5.8 to 6.9) thermal (T from 25.7°C to 63.0°C) HCO3–SO4 waters are thought to have formed by the absorption of a H2S/SO2–CO2-enriched steam into a Cl-rich geothermal aquifer, afterwards mixed by Na/HCO3-enriched meteoric waters originating from the higher elevations of the volcano as stated by the isotopic composition (δD
and δ18O) of meteoric and spring waters. Boiling temperature fumaroles (89°C at ~3,600m a.s.l. NW of the summit), formed after the
May 1986 phreatic explosion, emit isotopically light vapour (δD and δ18O as low as −128 and −19.9‰, respectively) resulting from steam separation from the summit aquifer. Fumarolic as well as bubbling
gases at five springs are CO2-dominated. The δ13CCO2 for all gases show typical magmatic values of −3.6 ± 1.3‰ vs V-PDB. The large range in 3He/4He ratios for bubbling, dissolved and fumarolic gases [from 1.3 to 6.9 atmospheric 3He/4He ratio (R
A)] is ascribed to a different degree of near-surface boiling processes inside a heterogeneous aquifer at the contact between
the volcanic edifice and the crystalline basement (4He source). Tacaná volcano offers a unique opportunity to give insight into shallow hydrothermal and deep magmatic processes
affecting the CO2/3He ratio of gases: bubbling springs with lower gas/water ratios show higher 3He/4He ratios and consequently lower CO2/3He ratios (e.g. Zarco spring). Typical Central American CO2/3He and 3He/4He ratios are found for the fumarolic Agua Caliente and Zarco gases (3.1 ± 1.6 × 1010 and 6.0 ± 0.9 R
A, respectively). The L/S (5.9 ± 0.5) and (L + S)/M ratios (9.2 ± 0.7) for the same gases are almost identical to the ones calculated for gases in El Salvador, suggesting an
enhanced slab contribution as far as the northern extreme of the Central American Volcanic Arc, Tacaná. 相似文献
95.
Visualization of spatial patterns and temporal trends for aerial surveillance of illegal oil discharges in western Canadian marine waters 总被引:1,自引:0,他引:1
This paper examines the use of exploratory spatial analysis for identifying hotspots of shipping-based oil pollution in the Pacific Region of Canada’s Exclusive Economic Zone. It makes use of data collected from fiscal years 1997/1998 to 2005/2006 by the National Aerial Surveillance Program, the primary tool for monitoring and enforcing the provisions imposed by MARPOL 73/78. First, we present oil spill data as points in a “dot map” relative to coastlines, harbors and the aerial surveillance distribution. Then, we explore the intensity of oil spill events using the Quadrat Count method, and the Kernel Density Estimation methods with both fixed and adaptive bandwidths. We found that oil spill hotspots where more clearly defined using Kernel Density Estimation with an adaptive bandwidth, probably because of the “clustered” distribution of oil spill occurrences. Finally, we discuss the importance of standardizing oil spill data by controlling for surveillance effort to provide a better understanding of the distribution of illegal oil spills, and how these results can ultimately benefit a monitoring program. 相似文献
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99.
Peter Rogerson 《Journal of Geographical Systems》2005,7(1):101-114
When assessing maps consisting of comparable regional values, it is of interest to know whether the peak, or maximum value, is higher than it would likely be by chance alone. Peaks on maps of crime or disease might be attributable to random fluctuation, or they might be due to an important deviation from the baseline process that produces the regional values. This paper addresses the situation where a series of such maps are observed over time, and it is of interest to detect statistically significant deviations between the observed and expected peaks as quickly as possible. The Gumbel distribution is used as a model for the statistical distribution of extreme values; this distribution does not require the underlying distributions of regional values to be either normal, known, or identical. Cumulative sum surveillance methods are used to monitor these Gumbel variates, and these methods are also extended for use when monitoring smoothed regional values (where the quantity monitored is a weighted sum of values in the immediate geographical neighborhood). The new methods are illustrated by using data on breast cancer mortality for the 217 counties of the northeastern United States, and prostate cancer mortality for the entire United States, during the period 1968-1998.The research assistance of Ikuho Yamada is gratefully acknowledged. I also am grateful for the support of Grant 1R01 ES09816-01 from the National Institutes of Health, the support of National Cancer Institute Grant R01 CA92693-0, and the helpful comments made by the referees 相似文献
100.
分析了数字地籍调查工程监理的难点,提出了监理工作的一般内容和关键事项,通过监理实践表明项目的进度、质量等得到了有效控制。 相似文献