【摘 要】
:
The permafrost development in the Qinghai-Tibet En-gineering Corridor (QTEC) is affected by natural environment changes and human engineering activities. Human engineering activities may damage the permafrost growing environment, which in turn impact thes
【机 构】
:
School of Land Science and Technology,China University of Geosciences(Beijing),Beijing 100083,China;
论文部分内容阅读
The permafrost development in the Qinghai-Tibet En-gineering Corridor (QTEC) is affected by natural environment changes and human engineering activities. Human engineering activities may damage the permafrost growing environment, which in turn impact these engineering activities. Thus high spa-tial-temporal resolution monitoring over the QTEC in the perma-frost region is very necessary. This paper presents a method for monitoring the frozen soil area using the intermittent coherence-based small baseline subset (ICSBAS). The method can im-prove the point density of the results and enhance the inter-pretability of deformation results by identifying the discontinu-ous coherent points according to the coherent value of time series. Using the periodic function that models the seasonal vari-ation of permafrost, we separate the long wavelength atmos-pheric delay and establish an estimation model for the frozen soil deformation. Doing this can raise the monitoring accuracy and improve the understanding of the surface deformation of the frozen soil. In this study, we process 21 PALSAR data acquired by the Alos satellite with the proposed ICSBAS technique. The results show that the frozen soil far from the QTR in the study area experiences frost heave and thaw settlement (4.7 cm to 8.4 cm) alternatively, while the maximum settlement along the QTR reaches 12 cm. The interferomatric syntnetic aperture radar (In-SAR)-derived results are validated using the ground leveling data nearby the Beiluhe basin. The validation results show the InSAR results have good consistency with the leveling data in displace-ment rates as well as time series. We also find that the deforma-tion in the permafrost area is correlated with temperature, hu-man activities and topography. Based on the interfering degree of human engineering activities on the permafrost environment, we divide the QTEC along the Qinghai-Tibet Railway into engi-neering damage zone, transition zone and natural permafrost.
其他文献
采用五孔探针流场测试系统对旋-喷管道式分解炉模型在不同截面风速下的流场进行测量,得到了各测点三维风速,绘制了分解炉在不同截面风速下的轴向、切向与径向速度分布图.结果表明:分解炉的流场主要受三次风的影响,三次风水平进入分解炉后分流为两股风,其中一股风螺旋向上运动,另一股风紧贴壁面先旋转向下运动,与烟室上升气流汇合后,再螺旋上升,并形成一处回流区;分解炉锥部与直筒缩口处存在喷腾效应;随着截面风速的增大,向下运动的三次风越显著,回流区域越大,缩口喷腾效应越明显.
背景rn轮胎式叉装机(简称叉装机)及其变形产品主要用于矿山搬运石材荒料、夹木材、装卸卷钢、集装箱旋转卸货等场合.叉装机占土方机械的市场份额相对较小,主要以厦门厦金机械股份有限公司、福建晋工机械有限公司、福建省威盛机械发展有限公司、龙工(福建)机械有限公司、龙工(上海)机械制造有限公司和广西柳工机械股份有限公司等为代表的生产厂家.早期市场上产品形式多样,出现标识混乱、功能互异,缺少检验依据,生产厂家和/或销售商与消费者纠纷较多.
具有持久疏水能力的控水型超低密度支撑剂是应对石油开采中高含水井或压裂施工中后期产出液高含水问题的关键材料.首先制备了结构致密和尺寸可控的轻质高强交联聚苯乙烯(CPS)微球,再通过氟树脂在CPS表面进行疏水覆膜改性,获得了疏水能力强且持久的、兼具高强度和超低密度的智能控水(LWC)微球.通过接触角测量仪监测LWC微球的疏水性和疏水稳定性,通过压力试验机和裂缝导流能力测试仪分别评价LWC微球的抗压强度和其对水、油的导流能力.结果表明:LWC微球的表观密度约1.047 g·cm-3,60 MPa闭合压力下的破碎
引言rn为确保工程项目建设水平有所提升,开展“工程项目管理”信息化工作显得尤为重要.目前集团型企业普遍建设综合管理平台,通过强化统一协同管理、移动应用,使各个业务板块实现信息互通并满足日常移动办公需求.笔者所在的福建省建筑科学研究院有限责任公司(以下简称福建建科院)也逐步着手整合企业现有的MIS系统(管理信息系统),以企业的管理、经营、考核为主线,形成“人、财、业务”完整的企业资源信息化应用架构.初步建立统一的数据规则,通过打通企业经营、生产、管理各个数据应用环节,沉淀关联数据形成企业数据资产[1].本文
采用乙二醇热还原法制备银纳米线,研究了溶液除氧、控制剂类型、反应时间和反应温度对其长径比的影响.结果表明:通过增加溶液除氧操作和引入三氯化铁控制剂,可以保护银孪晶不受O2/Cl-协同作用的刻蚀,大幅提高银纳米线的长度和纯度;在合适的反应时间和温度条件下获得了直径约100 nm、长度300~400μm、长径比达到3000~4000的超长银纳米线,为合成超高长径比银纳米线提供了一个简单高效的方案.
为研究碳纤维电加热材料表面的发热均匀性,设计了一种由碳纤维丝束与碳纤维布复合而成的碳纤维复合材料板,下侧基体部分为4层碳纤维布/环氧树脂预浸料,上侧发热功能部分为碳纤维发热丝/环氧树脂预浸料.实验研究了碳纤维丝布置间距与加热功率对复合板表面发热温度的影响,并在已有试验结果的基础上提出了复合板表面温度差拟合公式.结果表明:复合板表面的温度差受碳纤维丝布置间距影响较大,受到加热功率影响较小,拟合结果与试验结果相接近,该经验公式可为碳纤维丝束加热复合板的设计提供理论参考.
随着环境和能源问题的日益突出,在城市公共交通领域,节能、环保的纯电动客车日益受到人们的认可.驱动电机是纯电动客车的动力源,其性能直接影响着车辆行驶的安全与品质.在车辆起步、加速、高速行驶时,电机工作在大电流的状况下,电机控制器与电机内耗会急剧增加,释放大量的热量,如果得不到有效的冷却,电机控制器与电机内部温度就会急剧升高,影响驱动电机的输出功率、效率及寿命,严重妨碍驱动系统正常行驶.
前言rn城市地下综合管廊(以下简称管廊)是将电力、通信、燃气、供热、给排水等各种工程管线集于一体,统一在城市地下建立一个隧道空间管理,是保障城市运行的重要基础设施.管廊以环网的形式存在于城市地下,总长度可达上百公里,面对如此庞大的管廊网络,采用先进的信息化技术对管廊进行检测和监控是十分有必要的.地下综合管廊的监控包括对运行中的管线安全状况的监测,以及对地下综合管廊内部环境的检测,避免内部环境因素对设备管线的影响及对工作人员的伤害,从已建的地下综合管廊运营状况来看,国内在研究信息化监控方面与国际水平较接近,
This paper focuses on the influence of the disturb-ance rejection rate (DRR) and parasitic loop parameters on the stability domain of the roll-pitch seeker \'s guidance system. The DRR models of the roll-pitch seeker caused by different types of disturb
In order to improve the autonomous ability of un-manned aerial vehicles (UAV) to implement air combat mission, many artificial intelligence-based autonomous air combat mane-uver decision-making studies have been carried out, but these studies are often ai