三面临空单薄破碎岩体帷幕灌浆设计与施工尝试

本文阐述了三面临空单薄破碎岩体帷幕灌浆的设计和施工方法，进而讨论和验证了该方法的合理性及效果，同时，本文还讨论了在类似条件下灌浆压力值的确定及施工工艺。工程经灌浆后十余年的检验，证明所采用的设计方案符合工程实际。     

Effect of altitude error on position precision of double-star position system

IntroductionDouble-Star is to use two stationary orbit satellitesto locate the target which is located in the overlayarea of the the satellites’wave-beam. The two sat-ellites can only supply two equations. In order toget the three-dimensional position of…     

哈依煤气工程管线GPS测量及数据处理

介绍哈依煤气工程管线ＧＰＳ控制网的布设、施测及观测数据处理,总结了长距离导线型ＧＰＳ控制网布设的可能性与经验。     

基于双正交小波的遥感图像融合研究

针对多光谱图像与全色图像融合中的光谱失真问题,采用一种双正交小波的方法进行融合。试验证明,该方法可以减少图像的失真问题,提高图像的空间分辨率,保留图像的边缘细节。     

从第三极到北极： 积雪变化研究进展

在全球气候变化背景下, 第三极和北极地区积雪是地表最活跃的自然要素之一, 其动态变化对气候环境和人类生活产生重要影响。通过回顾第三极和北极积雪研究进展, 阐述了降雪、 积雪范围、 积雪日数、 积雪深度和雪水当量在第三极和北极地区的时空分布特征和变化趋势。结果表明： 近50年, 特别是进入21世纪以来, 第三极和北极地区降雪比率均呈下降趋势; 积雪范围、 积雪日数、 积雪深度、 雪水当量总体均呈减小趋势, 融雪首日有所提前。同时就积雪变化对生态系统与气候系统的影响进行了论述, 评估了积雪的反馈作用。通过总结第三极和北极积雪变化研究进展, 凝练研究中存在的不足和未来发展趋势, 为提升积雪对气候变化及经济社会发展影响的认识提供重要科学支撑。     

Development of 57 novel polymorphic microsatellite markers in half-smooth tongue sole (Cynoglossus semilaevis)

Half-smooth tongue sole (Cynoglossus semilaevis) is a promising species for aquaculture in China.The wild population of C. semilaevis is under threat from environmental factors. Microsatellite markers are very suitable for assessing genetic diversity. Four microsatellite-enriched libraries of half smooth tongue sole (Cynoglossus semilaevis) were constructed,from which 57 polymorphic microsatellites were isolated and characterized.The polymorphism of these microsatellites was assessed by genotyping in 30 ind...     

祁连山区黑河流域季节冻土时空变化研究

季节冻土的时空变化对地—气水热交换、地表能量平衡、地表水文过程、生态系统及碳循环等有着非常重要的影响.利用黑河流域11个气象站40多年的气温数据和5 cm深度处的土壤温度数据,建立了月平均气温与土壤冻结天数之间的关系.同时应用月平均气温与冻结天数的相关关系和5 km网格化月平均气温及30 m分辨率的DEM数据,编制了黑河流域逐月季节冻土分布图,并按其空间分布特征,将逐月地表冻融状态划分为:完全冻结、不完全冻结和不冻结3种.系统研究了黑河流域2000-2009年逐月季节冻土分布及冻结概率的时空变化特征.在季节分配上,黑河流域完全冻结面积最大值出现在1月;不完全冻结面积最大值在11月;而不冻结面积最大值在6月和7月.在年际变化上,完全冻结状态的离差值在冷季变化大,暖季变化小;不完全冻结状态在一年的回暖期和降温初期,年际变化较大;不冻结状态分别在4月和10月变化较大.冻结概率在1月达到最大值,6月和7月降低到最小值.在空间分布上,黑河流域季节冻土的逐月分布与变化和冻结概率主要受海拔高度控制,纬度的影响次之.     

Spatial and Temporal Distribution and Variations in the Near-surface Soil Freezing Days across China, 1956-2006

Using surface soil daily minimum temperature from 845 meteorological stations across China, the long-term (1971-2000) mean and spatial distribution of the near-surface soil freezing days were estimated with annual values of the number of near surface soil freezing days. The time series for the number of freezing days were constructed and compared with air temperatures in the same period.Resultsshowed that long term mean value in the number of the near surface soil freezing days increased with the increasing latitudes and altitudes over China. Near-surface soils were frozen for more than 200 days in the Qinghai Tibet Plateau, northern Xinjiang and northeast of China. The boundaries of permafrost zones coincide with the contour of (220±10) days of near-surface soil freezing. Using the mean number of 15 days of near-surface soil freezing as criterion, we found that the southern boundary of seasonally frozen ground is around the 25°N line, and the regions south of 22°N are essentially unfrozen regions. The time series of the number of freezing days showed a significant linear trend with change with a slope of -0.22days/year over a period from 1956 through 2006. After the 1990s, the linear slope was up to -1.02 days / year, indicating that the rate of decrease in the number of near-surface soil freezing days has accelerated. Changes in the number of near surface soil freezing were in a negative correlation with air temperature, i.e., the number of near-surface soil freezing days decreases with increase in air temperature.Backgroundcolor represents the contour values of the departure of near-surface soil freezing days from the 1971-2000 mean; Black dashed line is the boundary of permafrost regions, red dashed line is the boundary between frozen and unfrozen ground regions in China     

基于ArcGIS Server的城市公共安全预警研究

城市公共安全是影响人类生存、生活的重要因素,建立一套行之有效的综合性的预警体系具有重要意义.以ArcGIS Server平台为基础,将WebGIS融合于城市公共安全中,设计出B/S模式的城市公共安全预警系统,并介绍系统的特色功能,最后展示系统的运行效果和努力方向.     

Major advances in studies of the physical geography and living environment of China during the past 70 years and future prospects

The natural environment provides material essentials for human survival and development. The characteristics,processes, regional differentiation and forcing mechanisms of the elements of the natural environment(e.g. geomorphology,climate, hydrology, soil, etc.) are the main objects of research in physical geography. China has a complex natural environment and huge regional differentiation and therefore it provides outstanding reserach opportunities in physical geography. This review summarizes the most important developments and the main contributions of research in the physical geography and human living environment in China during the past 70 years. The major topics addressed are the uplift of the Tibetan Plateau and the evolution of its cryosphere, the development of fluvial systems, the acidification of the vast arid region of the Asian interior, variations in the monsoon and westerly climate systems on multiple timescales, the development of lakes and wetlands, the watershed system model, soil erosion, past human-environment interactions, biogeography, and physical geographic zonality. After briefly introducing international research developments, we review the history of research in physical geography in China, focusing on the major achievements and major academic debates, and finally we summarize the status of current research and the future prospects. We propose that in the context of the national demand for the construction of an ecological civilization, we should make full use of the research findings of physical geography, and determine the patterns and mechanisms of natural environmental processes in order to continue to promote the continued contribution of physical geography to national development strategies, and to further contribute to the theory of physical geography from a global perspective.