期刊文献+
共找到70篇文章
< 1 2 4 >
每页显示 20 50 100
光测方法在岩石力学实验观测中的应用述评 被引量:22
1
作者 马少鹏 赵永红 +2 位作者 金观昌 潘一山 王来贵 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2005年第10期1794-1799,共6页
综述了常用光测方法在岩石力学实验观测中的应用,总结了这些光测方法相对于岩石力学中常用的其他方法的特点。最后在分析岩石力学实验观测新趋势的基础上,指出发展一种以数字散斑相关方法(DSCM)为基础的岩石力学观测系统,将可以满足岩... 综述了常用光测方法在岩石力学实验观测中的应用,总结了这些光测方法相对于岩石力学中常用的其他方法的特点。最后在分析岩石力学实验观测新趋势的基础上,指出发展一种以数字散斑相关方法(DSCM)为基础的岩石力学观测系统,将可以满足岩石力学观测中的新的需要。 展开更多
关键词 岩石力学 实验 光测方法 变形场 数字散斑相关方法
下载PDF
实验力学中现代光学方法的发展与应用前景 被引量:11
2
作者 伍小平 《机械强度》 CAS CSCD 北大核心 1995年第2期20-25,54,共7页
对现代光测实验力学的发展做了简要的回顾。随着高新技术的发展,现代光学方法日趋方便和易于接受,特别是图像处理技术的发展,使现代光测方法的应用扩展到相当大的范围,在基础研究和工程应用方面都将发挥大的作用。
关键词 实验力学 现代光测方法 力学
下载PDF
高美古观测站大气消光系数测定的初步结果 被引量:5
3
作者 胡波 《天文学报》 CSCD 北大核心 2010年第4期422-431,共10页
大气消光系数的测定是天文观测台站一项很重要和基础的工作.介绍了利用新建的2.4 m望远镜在高美古观测站开展的消光系数测定等定标工作的初步结果.利用2009年4~5月对Landolt标准星场的2次测光观测,分别给出了UBVRI 5个波段的消光系数.... 大气消光系数的测定是天文观测台站一项很重要和基础的工作.介绍了利用新建的2.4 m望远镜在高美古观测站开展的消光系数测定等定标工作的初步结果.利用2009年4~5月对Landolt标准星场的2次测光观测,分别给出了UBVRI 5个波段的消光系数.此外,对该站点大气消光的成分情况进行了探讨.给出的结果与数年前高美古观测站选址时得到的大气消光系数基本一致,并与其它一些知名天文观测台站的消光数据进行了比较. 展开更多
关键词 大气效应 技术: 方法:数据分析
下载PDF
日本白光LED测量标准
4
《电源技术应用》 2010年第1期64-65,共2页
日本四团体共同制定的《照明用白色LED测光方法通则》为目前唯一针对照明用白光发光二极管(WLED)所制定的测量标准,本文将对其内容进行介绍及分析,以供读者及有关产、学、研部门参考。
关键词 量标准 LED 日本 二极管 方法 照明
下载PDF
建筑工程结构检测方法及重点
5
作者 刘少庆 《新材料·新装饰》 2022年第15期142-144,共3页
文章首先阐述了建筑工程结构检测的重要性,其次列举了建筑工程结构检测的具体方法,最后提出了建筑工程结构检测的重点,包括做好建筑结构的外观检测、加强建筑主体的强度检测,以期为相关的建筑工程结构检测提供借鉴。
关键词 建筑工程 结构检 方法
下载PDF
正确测光 拍出明暗适中的照片
6
《电脑应用文萃》 2005年第11期58-58,共1页
一次难得的旅行中,我们通常都会拍下许多照片来纪录美好的瞬间,但似乎总有一些珍贵的镜头因为照片画面太暗或者太亮而难如人意。其实想避免这个问题并不难,只要了解一定的测光方法和技巧,就能让你拍摄的照片不再明暗不均了。
关键词 方法 照片 明暗 镜头 拍摄
下载PDF
机动车灯光及信号装置测光实验室考查报告
7
作者 陈昌鸿 黄强 《灯与照明》 2006年第4期6-8,共3页
机动车(汽车、摩托车等)灯光照明装置(前照灯、前雾灯等)和光信号指示装置(前后位置灯、前后转向灯等)的配光性能是保证行车安全的一项重要指标,国家强制性安全标准对上述各类产品配光性能的要求、测试方法等作出了明确的规定。笔者在... 机动车(汽车、摩托车等)灯光照明装置(前照灯、前雾灯等)和光信号指示装置(前后位置灯、前后转向灯等)的配光性能是保证行车安全的一项重要指标,国家强制性安全标准对上述各类产品配光性能的要求、测试方法等作出了明确的规定。笔者在对重庆市部分重点摩托车生产企业测光实验室的考查中发现了诸多有关测量方法、测量仪器性能及测量仪器配置等方面值得探讨的问题,并对相关问题提出了改进建议。 展开更多
关键词 机动车灯照明装置 方法 量仪器
下载PDF
彗星的CCD成像观测
8
作者 周洪楠 黄克谅 《中国科学院上海天文台年刊》 2000年第S1期64-71,共8页
近年来 ,对一系列彗星进行的宽带或窄带CCD测光得到了许多有趣的结果 ,为深入地理解彗星的物理性质、结构、起源和演化等提供了丰富的信息。文中简要地介绍利用CCD成像观测在测量彗核的自转、大小、形状、质量和研究彗核的活动以及彗发... 近年来 ,对一系列彗星进行的宽带或窄带CCD测光得到了许多有趣的结果 ,为深入地理解彗星的物理性质、结构、起源和演化等提供了丰富的信息。文中简要地介绍利用CCD成像观测在测量彗核的自转、大小、形状、质量和研究彗核的活动以及彗发的形成和演化等方面的进展。 展开更多
关键词 彗星 方法:
下载PDF
环氧基玻璃纤维层合板力学性能的实验研究 被引量:1
9
作者 蒲琪 任传波 《山东理工大学学报(自然科学版)》 CAS 2003年第4期40-43,共4页
采用现代光测方法,对两种铺层方式的环氧基玻璃纤维层合板的力学性能进行了实验研究,实验揭示了两种铺层方式层合板的力学性能,给出弹性常数的计算公式和测定方法。
关键词 环氧基玻璃纤维层合板 力学性能 复合材料层合板 现代光测方法 弹性常数
下载PDF
小波变换用于数字图像相关法位移场的平滑处理 被引量:2
10
作者 唐晨 闫海青 +2 位作者 佟景伟 李鸿琦 张皞 《天津大学学报(自然科学与工程技术版)》 EI CAS CSCD 北大核心 2002年第5期577-580,共4页
基于小波多分辨率分析 ,对数字散斑相关法获得的位移场进行平滑处理 .将含噪声的位移场进行小波分解 ,获得在不同尺度上的小波系数 ;根据位移和噪声在频率上的区别 ,消除属于噪声的小波系数 ,从而实现噪声滤除 ;讨论了小波基的选择和去... 基于小波多分辨率分析 ,对数字散斑相关法获得的位移场进行平滑处理 .将含噪声的位移场进行小波分解 ,获得在不同尺度上的小波系数 ;根据位移和噪声在频率上的区别 ,消除属于噪声的小波系数 ,从而实现噪声滤除 ;讨论了小波基的选择和去除属于噪声的小波系数关键技术问题 .实验结果表明位移场的噪声得到了很好的滤除 .此方法尤其适用于非平稳位移场噪声的平滑处理 。 展开更多
关键词 小波变换 数字图像相关法 位移场 平滑处理 小波多分辨率分析 消噪处理 小波系数 实验力学方法
下载PDF
AN HIERARCHICAL OCCLUSION TEST ALGORITHM FOR GLOBAL ILLUMINATION SOLUTION
11
作者 孙济洲 吴奇 +1 位作者 邢昌玉 GrimsdaleRL 《Transactions of Tianjin University》 EI CAS 1998年第1期37-41,共5页
This paper presents an efficient hierarchical occlusion test algorithm to support the global illumination solution such as Ray Tracing and Radiosity. This method, which is based on a cone volume intersection examinati... This paper presents an efficient hierarchical occlusion test algorithm to support the global illumination solution such as Ray Tracing and Radiosity. This method, which is based on a cone volume intersection examination, can rapidly remove the irrelevant parts in a scene and find the vertices which fall into the shadow area of a given object. It is an effective alternative to the conventional shadow feeler method. 展开更多
关键词 global illumination RADIOSITY occlusion test Information Engineering
下载PDF
Identification of serum proteins discriminating colorectal cancer patients and healthy controls using surface-enhanced laser desorption ionisation-time of flight mass spectrometry 被引量:45
12
作者 Judith YMN Engwegen Helgi H Helgason +4 位作者 Annemieke Cats Nathan Harris Johannes MG Bonfrer Jan HM Schellens Jos H Beijnen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第10期1536-1544,共9页
AIM: To detect the new serum biomarkers for colorectal cancer (CRC) by serum protein profiling with surfaceenhanced laser desorption ionisation - time of flight mass spectrometry (SELDI-TOF MS). METHODS: Two ind... AIM: To detect the new serum biomarkers for colorectal cancer (CRC) by serum protein profiling with surfaceenhanced laser desorption ionisation - time of flight mass spectrometry (SELDI-TOF MS). METHODS: Two independent serum sample sets were analysed separately with the ProteinChip technology (set A: 40 CRC + 49 healthy controls; set B: 37 CRC + 31 healthy controls), using chips with a weak cation exchange moiety and buffer pH 5. Discriminative power of differentially expressed proteins was assessed with a classification tree algorithm. Sensitivities and specificities of the generated classification trees were obtained by blindly applying data from set A to the generated trees from set B and vice versa. CRC serum protein profiles were also compared with those from breast, ovarian, prostate, and non-small cell lung cancer. RESULTS: Mass-to-charge ratios (m/z) 3.1×10^3, 3.3× 10^3, 4.5×10^3, 6.6×10^3 and 28×10^3 were used as classitiers in the best-performing classification trees. Tree sensitivities and specificities were between 65% and 90%.Host of these discriminative m/z values were also different in the other tumour types investigated. M/z 3.3× 10^3, main classifier in most trees, was a doubly charged form of the 6.6× 10^3-Da protein. The latter was identified as apolipoprotein C-I. M/z 3.1×10^3 was identified as an N-terminal fragment of albumin, and m/z 28× 10^3 as apolipoprotein A-I. CONCLUSION: SELDI-TOF MS followed by classification tree pattern analysis is a suitable technique for finding new serum markers for CRC. Biomarkers can be identified and reproducibly detected in independent sample sets with high sensitivities and specificities. Although not specific for CRC, these biomarkers have a potential role in disease and treatment monitoring. 展开更多
关键词 PROTEOMICS Colorectal cancer BIOMARKER Sensitivity SPECIFICITY
下载PDF
A New Method for Measurement of Local Solid Flux in Gas-Solid Two-phase Flow 被引量:8
13
作者 鄂承林 卢春喜 +2 位作者 徐春明 高金森 时铭显 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第6期617-621,共5页
Previous works have shown that the suction probe cannot be used to accurately measure the upward and downward particle fluxes independently. A new method using a single optical probe to measure the local solid flux is... Previous works have shown that the suction probe cannot be used to accurately measure the upward and downward particle fluxes independently. A new method using a single optical probe to measure the local solid flux is presented. The measurement of upward, downward and net solid fluxes was carried out in a cold model circulating fluidized bed (CFB) unit. The result shows that the profile of the net solid flux is in good agreement with the previous experimental data measured with a suction probe. The comparison between the average solid flux determined with the optical measuring system and the external solid flux was made, and the maximum deviationturned out to be 22%, with the average error being about 6.9%. These confirm that the optical fiber system can be successfully used to measure the upward, downward and net solid fluxes simultaneously by correctly processing the sampling signals obtained from the optical measuring system. 展开更多
关键词 fluidized bed measuring method optical fiber probe local solid flux
下载PDF
Bending Modulus Measurement of Single High Performance Fiber 被引量:1
14
作者 刘宇清 胡超能 于伟东 《Journal of Donghua University(English Edition)》 EI CAS 2007年第2期151-156,共6页
The bending modulus property of high performance fiber is an important property for both polymer science and engineering. The measurement of the bending performance is, however, difficult because of the thin size of t... The bending modulus property of high performance fiber is an important property for both polymer science and engineering. The measurement of the bending performance is, however, difficult because of the thin size of the fiber. We have measured this property by the axial compression bending method where single fiber with suitable slenderness is compressed in the fiber axial direction to obtain the peak point of the force-displacement curve. Then the bending modulus and the flexural rigidity can be calculated by measuring the protruding length and diameter of fiber needles and the critical force, Pcr. The measured data show that the bending characteristics of all kinds of high performance fiber are dissimilar evidently. 展开更多
关键词 single fiber tending modulus high performancefiber
下载PDF
Novel fiber-optical interferometer with miniaturized probe for in-hole measurements 被引量:3
15
作者 Robert Schmitt Tilo Pfeifer +1 位作者 Frank Depiereux Niels Knig 《Optoelectronics Letters》 EI 2008年第2期140-142,共3页
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to en... Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible. 展开更多
关键词 纤维 干扰术 技术 方法
下载PDF
Optical molecular imaging for detection of Barrett's-associated neoplasia 被引量:3
16
作者 Nadhi Thekkek Sharmila Anandasabapathy Rebecca Richards-Kortum 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第1期53-62,共10页
Recent advancements in the endoscopic imaging of Barrett's esophagus can be used to probe a wide range of optical properties that are altered with neoplastic progression.This review summarizes relevant changes in ... Recent advancements in the endoscopic imaging of Barrett's esophagus can be used to probe a wide range of optical properties that are altered with neoplastic progression.This review summarizes relevant changes in optical properties as well as imaging approaches that measures those changes.Wide-field imaging approaches include narrow-band imaging that measures changes in light scattering and absorption,and autofluorescence imaging that measure changes in endogenous fluorophores.High-resolution imaging approaches include optical coherence tomography,endocytoscopy,confocal microendoscopy,and high-resolution microendoscopy.These technologies,some coupled with an appropriate contrast agent,can measure differences in glandular morphology,nuclear morphology,or vascular alterations associated with neoplasia.Advances in targeted contrast agents are further discussed.Studies that have explored these technologies are highlighted;as are the advantages and limitations of each. 展开更多
关键词 Barrett's esophagus Barrett's metaplasia DYSPLASIA Esophageal adenocarcinoma ENDOSCOPY Imaging
下载PDF
Synthesis and fluorescence properties of Tb(Ⅲ) complexes with pyridine-2,6-dicarboxylic acid derivatives 被引量:2
17
作者 唐瑞仁 郑由浒 顾国梁 《Journal of Central South University of Technology》 2008年第5期599-605,共7页
Two novel ligands named 4-styrylpyridine-2,6-dicarboxylic acid (4-SPDA) and 4-(4-(2-(2, 6-dicarboxypyridin-4-yl)- vinyl)styryl)pyridine-2,6-dicarboxylic acid(DSPDA) and their complexes with Tb(Ⅲ) were synthesized and... Two novel ligands named 4-styrylpyridine-2,6-dicarboxylic acid (4-SPDA) and 4-(4-(2-(2, 6-dicarboxypyridin-4-yl)- vinyl)styryl)pyridine-2,6-dicarboxylic acid(DSPDA) and their complexes with Tb(Ⅲ) were synthesized and characterized by infrared spectrometry, 1H nuclear magnetic resonance, elemental analysis and gas chromatograph-mass spectrometry. The ligand synthetic route was optimized. The fluorescence properties of the complex in solid state, in different kind of solvents and in solutions with different pH values were investigated in detail. The results show that the yields of DSPDA and 4-SPDA reach over 78% by Wittig-Horner reaction and other eight pyridine-2, 6-dicarboxylic acid derivatives with different substituents on pyridine ring, and their complexes with Tb(Ⅲ) are also obtained. The fluorescence intensities of the complexes with electron-donating groups are more intense than those of the complexes with electron-withdrawing groups on pyridine ring; fluorescence intensities of the complexes are the strongest in neutral solution (pH=7), and the less the dipole moment of solvent molecule is, the stronger the fluorescence intensity is. It is found that the two ligands (4-APDA and DSPDA) are the good sensitizers for Tb(Ⅲ) ion. 展开更多
关键词 Tb(Ⅲ) complexes pyridine-2 6-dicarboxylic acid derivatives SYNTHESIS fluorescence property
下载PDF
A new optimal approach to segmentation of 2D range scans to line sections 被引量:1
18
作者 张亮 蒋荣欣 陈耀武 《Journal of Central South University》 SCIE EI CAS 2009年第5期807-814,共8页
In order to obtain a compact and exact representation of 2D range scans,UKF(unscented Kalman filter) and CDKF(central difference Kalman filter) were proposed for extracting the breakpoint of the laser data. Line extra... In order to obtain a compact and exact representation of 2D range scans,UKF(unscented Kalman filter) and CDKF(central difference Kalman filter) were proposed for extracting the breakpoint of the laser data. Line extraction was performed in every continuous breakpoint region by detecting the optimal angle and the optimal distance in polar coordinates,and every breakpoint area was constructed with two points. As a proof to the method,an experiment was performed by a mobile robot equipped with one SICK laser rangefinder,and the results of UKF/CDKF in breakpoint detection and line extraction were compared with those of the EKF(extended Kalman filter) . The results show that the exact geometry of the raw laser data of the environments can be obtained by segmented raw measurements(combining the proposed breakpoint detection approach with the line extraction method) ,and method UKF is the best one compared with CDKF and EKF. 展开更多
关键词 line extraction breakpoint detection unscented Kalman filter central difference Kalman filter extended Kalman filter
下载PDF
Measurement of Rotatory Optics Element in Tensor Dielectric Matrix for Rotatory Optical Fiber
19
作者 刘敬浩 张晓帆 +1 位作者 李华舟 鲍振武 《Transactions of Tianjin University》 EI CAS 2005年第2期115-118,共4页
The rotatory optics element in the tensor dielectric coefficient matrix is an important para-(meter) for analyzing and calculating a rotatory optical fiber by electromagnetic theory. But the mea-(surement) of rotatory... The rotatory optics element in the tensor dielectric coefficient matrix is an important para-(meter) for analyzing and calculating a rotatory optical fiber by electromagnetic theory. But the mea-(surement) of rotatory optics element is difficult for the rotatory optical fiber. A simple principle and method for measuring rotatory optics element are put forward in this paper. Firstly by using electromagnetic theory it was demonstrated that the rotatory optics element has a simple linear relation with the rotatory angle, and then the rotatory optics element has a simple linear relation with the magnetic field strength (or bias current in the helix coil) . Secondly a measurement system for the rotatory optics element in the rotatory optical fiber was designed. Using the measurement system the rotatory element can be obtained by measuring the bias current simply. 展开更多
关键词 rotatory optics element tensor dielectric coefficient rotatory optic fiber polarized light
下载PDF
Application of Spatial Filtering Techniques in the Measurement of the Velocity 被引量:1
20
作者 LIPing MABaoming 《Semiconductor Photonics and Technology》 CAS 1998年第1期56-61,共6页
As one of the interesting optical techniques for measurements of the velocity,the spatial filtering method is treated briefly in this paper.We shown theoretical analysis and calculation of spatial filtering velocimetr... As one of the interesting optical techniques for measurements of the velocity,the spatial filtering method is treated briefly in this paper.We shown theoretical analysis and calculation of spatial filtering velocimetry,and discussed two-dimensional measurements of the velocity.About the data processing,we used A/D conversion and interfaced with a microcomputer,so that the data can be processed automatically by the microcomputer.The preliminary experiment was performed and the experimental results show the usefulness of the present method for measurements of the velocity. 展开更多
关键词 MEASUREMENT Spatial Filtering VELOCITY
下载PDF
上一页 1 2 4 下一页 到第
使用帮助 返回顶部