The techniques introduced include the imaging of surface - opening cracks , the three dimensional scan of surface - opening cracks , and the imaging of internal defects using time domain or frequency domain signals 本文介绍数种利用弹性波建构混凝土缺陷影像的技术，包括表面裂缝影像法、表面裂缝三维扫描法，以及时间域和频率域的内部缺陷影像法。
In the method , two transducers were deposited by the two opposite sides of the test member in experiment . based on the attenuation of energy received after the pulse wave penetrates through the test surface , the interior faults can be detected 超声透射法通常采用两个换能器,分别布置在试件两侧,依据脉冲波穿透试件后的能量的变化来判断内部缺陷。
So monitoring partial discharge signals on - line and identifying the types of discharge look like very necessary . by doing so , weakness of insulation and the developing degree can be discovered in time , which can stop accidences 局部放电是导致绝缘劣化的重要因素，在线监测局部放电信号并识别放电类型，能够及时发现绝缘内部缺陷及放电发展程度，防止事故发生。
The context analyzed current detecting methods and proposed a new method to orient inner welding seam defect of intersecting joints in steel structure , according to the most typical construct characteristic of y joints in tubular structure 本文分析了现有的探伤方法,根据管结构中最有代表性的y型节点的构造特点,提出了一种在钢结构相贯节点中确定焊缝内部缺陷位置的新方法。
After the experiment of sample log was carried out . the software is correct and accurate . to distinguish the log internal defect by x - ray scanner provide the essential theory premise and technology for the design and application of wood flaw detecting and discerning 本论文研究的利用x射线测定原木内部缺陷的理论，为工业化木材缺陷计算机视频检测设备的设计与应用，提供了必要的理论前提和技术基础。
It built ultrasonic sound beam equation based on each construction parameter of tube - tube joints . the equation can orient the defect in the welding seam of complex tube - tube joints . through computer aid calculation , the location can be confirmed rapidly 以管-管节点的各结构参数为基础,建立了超声声束方程,通过该方程可以确定复杂的管-管节点焊缝中缺陷的方位,通过计算机辅助计算,可以快速确定焊缝内部缺陷位置。
In the process of metal plasticity forming , due to irrationality of process technology and mould design , it lead to external and interior failures on the product . the failures must induce mould to amend time amd time , even lead to the mould ' s discarding as useless 金属塑性成形过程中，往往由于加工工艺，模具设计的不合理等因素而导致产品出现表面缺陷或内部缺陷。缺陷的存在，必然造成模具的反复修改，甚至造成模具的报废。
In order to deal with effect of the high damping , focusing probe with focused sound field is used in testing . the image device of ultrasonic c - scanning , which has functions of ultrasonic testing , pc - based control , data collection , data storage , data processing and image displaying together , is applied in testing for the sake of visual testing result 为了克服高阻尼影响，采用了具有声束聚焦性能的聚焦换能器对不同形状的该种复合材料工件进行检测；为了得到直观的检测结果，运用了将超声检测与微机控制和微机进行数据采集、存贮、处理、图像显示集合在一起的超声c扫描成像技术，并得到了工件内部缺陷的横截面图。
It demonstrates the knowledge and application of geo - detective radar , as well as mainly elaborates on the principles of inspection of tunnel lining depth ( including depth of concrete as lining ; internal defects and the degree of compaction lining backward etc . ) ; combining the case practice in the inspection of depth and defects of many tunnels , it demonstrates the outstanding effect of geo - detective radar when it is applied to the inspection of tunnel lining depth 本文通过对探地雷达的认识和应用，重点论述了铁路隧道衬砌厚度的检测(包括衬砌混凝土的厚度、内部缺陷等等)的原理，通过对多座隧道衬砌厚度及缺陷的实际检测，论证了探地雷达在铁路隧道施工质量检测方面的应用是可行的和有效的，其作用是显著的。
By the increasing of temperature , liyco3 - xo4 was further changed into licoo2 and lixco1 - xo , and then licoo2 formed by the reaction of lixco1 - xo with li2o . the reaction that produces licoo2 is almost completely done at 700 , although some remaining li2o and li2co3 present as a partially amorphous film dispersed on the surface of licoo2 , which can accelerate the growth of licoo2 crystallites . however , when temperature is higher than 850 , some of licoo2 begin to decompose into the solid solution phase of liyco2 - yo2 and lixco1 - xo , and damaged its own crystal structure 制备licoo _ 2的合成反应中licoo _ 2的微结构不断发生变化，随着焙烧温度升高， co _ 3o _ 4晶粒逐渐减小， licoo _ 2晶粒和颗粒逐渐长大，晶格内部缺陷减少， licoo _ 2晶格趋于完整，在焙烧温度为850时licoo _ 2晶粒达到最大值；焙烧温度低于700 ，晶胞参数a随着焙烧温度上升而减小，晶胞参数c随着焙烧温度上升而增大；而高于700则晶胞参数基本保持不变。
