Practice of Convergence Displacement Measurement of Surrounding Rock in Tongyu Tunnel

Tongyu tunnel has the following characteristicsuch as complex geological condition, deep depth, frequent water in flow, rock burst , high stress, etc., which seriously threaten the construction safety. In the tunnel construction, monitoring measurement is adopted strictly, especially for the convergence displacement measurement, and these data is processed in time to be turn back to the construction, then the stabilizationof the surroundingrock after being opened is known and the right measurement will be taken. The authors mainly introduce convergencedisplacementmeasurement technologyof the surrounding rocksand the theoryof data regression analysein the Tongyu Tunnel. the measurement result in Tongyu tunnel is shown, and it is expected to be reference to the similar engineer in future.     

Stress Measurement and Deformation Control of Support System in Shallow Light Railway Tunnel

Combined with the real example of monitoring pressure on the supporting system in the long span underground space of DK7+692 section at Jiao-Xin line of Chongqing light railway,it is set forth the methods about choosing the support system and its parameter,digging methods of underground space,measuring and testing methods for the stress of the support system;the testing results and variation pattern were analyzed for the stress of the initial supporting I-steel,axial stress of bolt,stress of shot-concrete,supporting pressure of temporary I-steel and stress of steel of the second lining,then,the reason for deformation of the support system induced by sharp increase of I-steel was determined.Based on this,considering the real problem,the construction plan and the support system is changed,the deformation of support system was under control and the danger was avoided,the informative construction and construction safety were realized.     

Application of GPS Technology in High-rise Building Axis Monitoring

In order to meet the modern construction demand,in this paper,with the project where the GPS technology used to monitor the axis of main teaching building of Chongqing University(verticality),the application of this technology is expounded.The result indicates,in high-rise construction,it is a kind of effective method to use GPS to control the axis.     

The Monitoring Measurements and Country Rock Control of NATM in Tunnel of Express Road during Construction

In this paper the author' s study on the monitoring measurement technique of NATM,the regularity and conditions of the country rock deformation are analysed based on the site measurement data in the west section of Zhongliangshan tunnel. The regression analysis of measure data for different measure lines of vavious country rock is done by the use of self-compiled CRAP program. The stability criterion for various rockmass and optimum time for primary and permanent support are provided. The conclusion available could conduct the theoretical research of NATM deeply as well as tunnel design and construction.     

New Sensing Technology Used in Bridge Deflection Automatic Monitoring

Deflection is one of the most important parameters in process of evaluating bridge's safety and developing structural health monitoring.The basic principles,characteristics and applied field of different sensing technologies in bridge deflection automatic monitoring are analyzed.And the corresponding measuring precision,measuring methods and applicability in different type bridges are also compared.The result shows that both high integration automatization and large scope measurement are developing directions in future.     

农产品安全生产和监控关键技术研究进展

基于“需求、亟待解决的问题、关键技术筛选”的思路,分析了中国农产品安全需求,提出了中国农产品安全生产和监控中存在的若干关键问题;归纳了作物新品种选育技术、农业投入品安全技术、现代设施农业技术、农产品安全监控信息化和智能化技术、农产品绿色贮藏技术、快速检测技术和农产品安全溯源技术在农产品安全生产和监控中的应用;并探讨了安全生产和监控关键技术在中国农产品领域的应用前景。     

Deformation Monitoring and Its Control in a Shallow buried Large span Tunnel Constructed Using the Pile Beam Arch Method

Deformation monitoring and control measures of a shallow buried large span tunnel constructed using the pile beam arch (PBA) method are described, taking the North Gongti Road Station of Beijing Metro line 10 as an example. Based on the monitoring datum, the crown settlement, convergence, ground settlement of the tunnel and the bridge foundation settlement are analyzed. The results show that (1) the PBA tunneling method can restrain the ground settlement and deformation of a shallow buried large span tunnel; (2) the depth, tunnel span and pilot tunnel construction may influence the deformation of a shallow buried large section tunnel significantly; and, (3) advanced conduit grouting, timely preliminary support and permanent lining construction can reduce the deformation effectively.     

遥感技术在烟草长势监测及估产中的应用进展

烟草长势信息是烟草生产管理的重要依据,全面了解遥感技术在烟草长势监测及估产中的应用进展,为利用遥感技术支撑科学化、精细化烟田管理提供科学参考。在对相关文献分析和归纳的基础上,从地面光谱、无人机遥感、卫星遥感3种尺度对目前遥感技术在烟草长势监测与估产方面的应用进行系统总结,并对进一步研究进行展望。(1)基于地面光谱对烟草的监测,主要是利用反射率光谱及其不同的变换形式、光谱指数和光谱位置变量估测其生理生化参量(氮、磷、钾、生物量、叶面积指数、叶绿素等),为诊断烟草生长、健康状况、成熟度提供依据,进一步实现烟草长势监测、估产与品质评定。(2)利用无人机遥感技术能够在小尺度上对作物的面积进行提取、监测长势及估产,但受搭载相机分辨率、地形、自身稳定性等影响,不能监测烟草的细微变化。(3)参考LandSat、SPOT、MODIS、HJ-1等光学遥感数据以及SAR数据,利用遥感影像融合、分类等技术能够实现对大面积烟田病害、长势进行监测和产量估计。结合多源、多平台遥感数据,对烟草的参数进行定量研究,并利用同化技术对大尺度上烟草生长过程进行动态监测,来探索烟草的最佳采收期是未来研究的重点。     

高超声速风洞进气道流量系数测量精度影响因素研究

进气道是飞行器动力装置的重要组成部分,准确测量进气道流量系数是进气道风洞试验的重要内容。对来流马赫数Ma=4.5,5.0和6.0状态下皮托管进气道开展流量系数测量研究,通过对比理论值和实测值,获取各状态流量系数修正系数。试验结果表明,随着来流马赫数增加,进气道流量系数与理论值偏差较明显,并逐渐增大。超声速风洞试验通常认为测量截面总温与来流总温相等,通过对测量截面总温与来流总温偏差以及测量截面流场畸变情况的分析,判断测量偏差主要是由测量截面总温等于来流总温的假设导致的。在高超声速风洞试验中,由于模型壁面热交换的存在,测量截面总温低于来流总温,进气道流量系数测量时需要进行总温修正,以提高流量测量精度。      

新型膜分离技术在现代农牧产品加工中的应用

介绍了膜技术的基本过程与特点,重点综述了各种膜分离过程在农牧产品加工不同行业中的应用情况,并对当前存在的问题和今后膜技术在该领域的应用进行了展望。     

气体射流冲击技术在果蔬干燥中的应用

干燥处理是果蔬加工的一项重要技术,气体射流冲击作为一种新型的干燥技术在果蔬干燥方面具有很强的优势。本文综述了目前果蔬干燥常用的技术方法及其优缺点,阐述了气体射流冲击干燥技术的原理、特点、影响因素和干燥工艺。与传统干燥方法相比较,气体射流冲击干燥技术具有对流换热系数大、干燥速度快、产品质量高、能耗低等优点,在果蔬干燥方面应用前景广阔。     

无人机遥感在森林资源监测中的应用研究进展

为了给森林资源监测中无人机遥感的应用研究提供依据,归纳了无人机遥感用于森林资源监测的技术流程,总结了在森林资源监测中常用的传感器类型,分析了无人机遥感在森林病虫害监测、林分树高测定、森林冠层结构与属性测定、树种组成识别、森林生物量测定中的应用和表现。得出通过无人机遥感搭载各种类型的传感器来收集森林信息,将是未来森林资源监测的一个重要方向;无人机遥感数字化、信息化、自动化提取森林结构参数将是无人机遥感用于森林资源监测中的发展趋势;此外,无人机遥感搭载多样化传感器以及传感器的小型化、商业化将进一步促进森林资源的精确监测。     

隧道式微波干燥处理对党参炔苷含量和菌落数的影响

采用隧道式微波干燥技术对党参进行灭菌处理,筛选适宜的灭菌工艺,并研究其对党参炔苷含量的影响。结果表明,微波干燥党参最优工艺为:料水质量比100∶15,传送带速度2.0 m/min,微波功率12 k W,载样量12.5 kg/m~2,党参灭菌工艺后菌落总数为3.1×10~3 CFU/g;高效液相色谱分析表明,隧道式微波灭菌技术对党参中有效成分党参炔苷无显著性影响。     

气味指纹分析技术在食品质控和风味研究的应用

着重以食用油、橙汁和奶制品为例,阐述了SensoryArrayFingerprinAtnalyzerMethod(气味指纹分析法)对食品所建立的新型质量控制和风味研究方法。经针对7种储存时间不同的食用油、脂(大豆油、菜籽油、猪油、牛脂、禽类脂、白色油脂、棕榈油)的过氧化值和酸价的分析模型的建立,展示了应用气味指纹分析技术(电子鼻)对食用油品质控制及抗氧化能力比较的新方法,对不同品质的橙汁(半年和一年半的鲜榨汁,和浓缩还原汁)、不同种类的鲜奶(灭菌全脂奶、灭菌半脱脂奶、半脱脂生奶和乳粉还原奶)和真伪某品牌奶粉的区分,表明该技术对复杂介质样品的品质变化具有独特的识别能力。分析结果表明,该分析技术具有以下优点:满意的分析灵敏度和重复性:传感器检测平均重复性为1.32%RSD(n=10),对同一样品测量的重复性为1.4%RSD(n=10),对所有油样的过氧化值和酸价测定具有良好的线性关系,平均相关系数为0.9984。不同品质样品之间区分指数DI的特异性明显(>90)。所有的数据通过化学计量学方法处理,并且该分析方法无需样品前处理。     

Reason and Precaution of Seepage in NATM Tunnel

On the basis of investigation on seepage in the Jinyunshan Tunnel and the Songjiagou No.1 Tunnel,the reasons of the seepage were analyzed and the cracking in concrete that led to seepage was studied by using the probability fracture mechanics.Finally,some suggestions of tunnel waterproofing were proposed.     

气味指纹分析技术在食品质控和风味研究的应用

着重以食用油、橙汁和奶制品为例,阐述了Sensory Array Fingerprint Analyzer Method(气味指纹分析法)对食品所建立的新型质量控制和风味研究方法.经针对7种储存时间不同的食用油、脂(大豆油、菜籽油、猪油、牛脂、禽类脂、白色油脂、棕榈油)的过氧化值和酸价的分析模型的建立,展示了应用气味指纹分析技术(电子鼻)对食用油品质控制及抗氧化能力比较的新方法,对不同品质的橙汁(半年和一年半的鲜榨汁,和浓缩还原汁)、不同种类的鲜奶(灭菌全脂奶、灭菌半脱脂奶、半脱脂生奶和乳粉还原奶)和真伪某品牌奶粉的区分,表明该技术对复杂介质样品的品质变化具有独特的识别能力.分析结果表明,该分析技术具有以下优点满意的分析灵敏度和重复性传感器检测平均重复性为1.32%RSD(n=10),对同一样品测量的重复性为1.4%RSD(n=10),对所有油样的过氧化值和酸价测定具有良好的线性关系,平均相关系数为0.998 4.不同品质样品之间区分指数DI的特异性明显(＞90).所有的数据通过化学计量学方法处理,并且该分析方法无需样品前处理.