非接触式围岩内部位移量测系统的试验研究

工程围岩内部位移的监控量测一直是一项费时费力的工作,特别是在工程断面大、量测距离远以及监测点供电困难等情况下,观测围岩内部位移尤为困难。为克服上述困难并提高监测效率,提出一套全新的非接触式围岩内部位移量测方案。方案通过将测点钻孔内的轴向位移转换为一种孔口转盘的旋转量,在该含有观测窗口的转盘下方装有环向灰度渐变膜片。通过望远光学摄像分析膜片反射光的强度,根据反射光强度模式的变化计算转盘旋转量,从而实现围岩内部位移的测量。通过室内标定试验,证实膜片的反射光强度模式与转盘转动角度之间有着很好的线性关系,通过建模,可有效提高围岩内部位移的分析精度。在龙门隧道工程现场对新量测方案进行验证,通过对比试验及围岩等级调查表明,量测结果与实际相符。新的围岩内部位移量测系统可实现非接触连续监测并达到工程测量精度要求。

新建地铁隧道下穿既有线车站安全影响分析

针对新建地铁隧道临近明挖及下穿暗挖条件下既有线车站的运营安全问题,以沈阳市新建九号线隧道下穿一号线(运营线路)为工程背景,通过数值模拟分析得出明挖及暗挖方案对既有线车站沉降及结构最大位移的影响均处于安全范围之内;制定既有线监控量测方案,结合自动化监测现场量测数据表明一号线铁西车站呈稳定状态,中洞破桩施工后局部断面已形成了明显的沉降槽,需要重视对变形区域的轨道平顺性的检测。自动化实时监测现场量测数据有利于及时掌握和提供地铁一号线对应区域在基坑明挖施工期及暗挖下穿期的状态信息,及时指导施工,起到了重要的地铁保护与安全保障的作用。

Roller Profile Online Measurement Based on Ultrasonic Circulation Pulse-echo Technology

In order to meet the high precision requirement of wide steel strip in industry field, a novel online measurement of roller profile based on sonic circulation and pulse-echo technology was introduced. All kinds of the factors influencing the accuracy of roller profile online measurement were analyzed in detail and error compensation analysis of system was accordingly presented. In order to reduce count error, field program gate array(FPGA) was introduced and a highprecision data acquisition system was designed based on digital phase-shift technology. Experiments indicate that the standard deviation of measure data was 7.27 μm, which showed the feasibility and validity of the proposed method, and realized the roll profile measurement with high precision.

Design of mobile sensing system for automatical measurement

Based on mobile devices as a solution for measurement faces interesting challenges, which involve poor human- computer interaction and limited computer capability. In this paper, we present the mobile sensing system （MSS） with func- tions of constructing, configuring and implementing measurement applications. MSS consists of a mobile device and a sensor probe, In the mobile device we install a pocket virtual instrument platform （PVIP）, which has object-oriented software ar- chitecture and can be configured through extensible markup language （XML） files. And these configuration files can be written to the probe. Therefore, the probe can produce the measurement of APP in the mobile device. This infrastructure has been illustrated by a sound signal acquisition task and a flexible force measurement task which are finished with an android smartphone and a probe. These examples suggest that MSS is reconfigurable, highly automatical and flexible.

A Modified Method for Measuring Root Iron Reductase Activity Under Normal Laboratory Conditions

Based on the strong chelating property of bathophenanthroline disulfonic acid (BPDS) with root chelate reductase activity is usually measured with a spectrophotometer using MES (2-morpholinoethanesulfonic acid) or HEPES (2-(4-(2-Hydroxyethyl)-1-piperazinyl) ethanesulfonic acid) buffer in the dark because of high autoreduction rate of in the presence of light. However, the exclusion of light is inconvenient, especially when analyzing a large number of samples. The objective of this study was to develop a new method for determination of root reductase activity under normal laboratory conditions using a suitable buffer composition and concentration to eliminate the autoreduction of A modified method using a Tris (2-amino-2-hydroxymethyl-1,3-propanediol) buffer at pH 7.5 instead of MES or HEPES buffer and a decreased FeEDTA (Fe ethylene diamine tetraacetic acid) concentration of 50 μmol L-1 was developed. The autoreduction of using the Tris buffer was undetectable for temperatures at 4 and 28 °C and was also much lower than that using the other buffers even with sunlight during measurement of reduction. Furthermore, the differences in reductase activity among 5 plant species and 14 red clover cultivars (Trifolium pratense L.) could be easily detected with the modified method. The method developed in this study to measure root Fe chelate reductase activity was not only effective and reliable but also easily managed under normal laboratory light conditions.

A new adaptive bending method using closed loop feedback control

As the competition from companies in low cost countries increases,the need for more automated production which reduces labour cost while improving product quality is required.A new rotary compression bending set-up with automated closed-loop feedback control is thus being developed.By transferring in-process measurement data into an algorithm for predicting springback and bend angle prior to the unloading sequence,the dimensional accuracy is improved.This work focuses on the development of this steering model.Since the method used does not increase cycle time,it is attractive for high-volume industrial applications.More than 150 bending tests of AA6060 extrusions were conducted to determine the capability of the technology.The results show that by activating the automated closed-loop feedback system,the dimensional accuracy of the bent parts is more than three times better than that obtained by traditional compression bending.Since the steering model permits the direct use of additional process data,such as instant wall thickness and cross sectional distortions,it is believed that extension of the measurement capabilities would improve the accuracy of the methodology even further.

Field-Based Automated Survey for Extracting Tree Inventory Attributes and 3-D Models in a Forested Area

Acquisition of tree inventory parameters such as tree position with respect to a local reference coordinate system, tree height, dbh （diameter breast height） and other associated tree attributes is a tedious process, time consuming, costly and labour intensive. An automatic collection and processing in the field could expedite the process of tree inventory survey and data management. The advent of handheld laser equipments such as the MDL LaserAce 300, should allow rapid acquisition of tree attributes. The instrument measures distances, differences in height and horizontal bearing automatically. This paper describes a study about the automated process of retrieving tree positions, their respective attributes and the creation of 3-D model （three-dimensional model）. A software developed in-house known as ASSIST （automated spatial survey information system） was utilized together with the MI）I, LaserAce 300, being the hardware component of the automated system. The capability of MDL LaserAce 9300 in extracting information regarding tree inventory attributes and the 3-D model encompassing the study area was investigated. The results were checked against the data sets acquired by a total station traversing and tacheometric survey respectively. The accuracy of the horizontal and vertical position of points gathered was critically assessed. The accuracy of the MDL LaserAce 300 was found to be less than ±2 m for both planimetric （horizontal） and vertical （height） in the construction of the 3-D model. The study demonstrates the effectiveness of a field-based automation system as a viable option to support forest application requirement.

A simple method to extract glacier length based on Digital Elevation Model and glacier boundaries for simple basin type glacier

Glacier length is a key morphological element that has many glaciological applications; however, it is often difficult to determine, especially for glaciers that cover larger spatial areas or those that exhibit frequent temporal change. In this paper, we describe a new Arc GIS-based method that can derive glacier flow lines for determining glacier length based on digital elevation model and glacier outlines. This method involves(1) extraction of the highest and lowest points on a glacier,(2) calculation of 10-m contour lines on the glacier from 10 m to 100 m height, and(3) connection of the midpoints of each contour line with the highest and the lowest points in order to create a flow line, which is subsequently smoothed. In order to assess the reliability of this method, we tested the algorithm's results against flow lines calculated using field measurements, analysing data from the Chinese Glacier Inventory, and manual interpretation. These data showed that the new automated method is effective in deriving glacier flow lines when contour lines are relatively large; in particular, when they are between 70 m and 100 m. Nonetheless, a key limitation of the algorithm is the requirement to automatically delete repeated and closed curves in the pre-treatment processes. In addition to calculating glacier flow lines for derivation of glacier length, this method also can be used to effectively determine glacier terminus change.

Proposal for a Project of Integration of IT Tools With Focus on Planning and Control of Operations on the Shop Floor

Manufacturing system, with high level of complexity and with a mix of semi-repetitive and repetitive products, to become productive, should seek the standardization of products and processes to obtain the optimization of use of production resources. However, it is necessary to measure the productivity, so that the system of measurement and control of manufacturing processes are an element critical as to ensure greater visibility of the flow＇s restrictions, minimized when detected properly. In this case, the automation of factory＇s measurement process can effectively contribute to ensuring the effectiveness of the function control of a manufacturing system. It is important to consider that the automation of the system of measurement and control of manufacturing processes, of complex environment, is heavily dependent of IT tools applied directly in the interface computational between the operation systems and the corporate systems. This heavy reliance, if exploited technically properly, allows that automation of the system of measurement and control of production makes the access to time real of availability of manufacturing process＇s data, such as processing time and setup time that it can export to a specialist software in programming production, for example, feasible. In this paper, the automation of the system of measurement and control of production is approached, in order to identify the main possibilities of the design of an information system capable to integrate the flow of information in an environment internal on manufacturing organizations, with emphasis in the digital manufacturing paradigm.

轨道交通地下桩基主动托换施工技术

桩基托换技术已经在国内各城市地铁施工中广泛采用,其有效地降低了施工成本和减少了拆迁纠纷,但鉴于国内目前主要使用桩基被动托换施工技术,对于主动托换的研究还较为少见,因此本项目的实施对于国内同类项目施工具有一定的指导意义。

业界信息

中国第三届PICMG技术年会在北京举行，第六届上海国际工业博览会召开自动化系统工程师资格认证工作正式启动，“江苏省制造业信息化示范工程工作交流研讨会”在无锡召开，“支持工业以太网与多协议转换技术的新型测控平台”通过鉴定……

经济实惠的Pentium M Solution PXI套装方案

凌华近日又推出一个Pentium M Solution PXI套装方案——PXI StarterⅡ。这个套装方案极为适用于计划将PXI系统引入量测自动化或数据采集系统的企业，它包含一个凌华科技最新推出的Pentium M PXI控制器PXI-3800和一个6槽3U PXI机箱PXIS-2506，操作简单，应用广泛，让您轻松架构数据采集系统，生产测试系统及自动测试设备。