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Run off-on-out method and models for soil infiltrability on hill-slope under rainfall conditions

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Science china Earth Sciences 2006年第2期49卷 193-201页

作者： LEI Tingwu1,2. LIU Han1, PAN Yinghua3, ZHAO Jun2. ZHAO Shiwei2.& YANG Yonghui2.1. The key laboratory of Modern {2. Agriculture System Integration Research, College of Hydraulic and Civil Engineer-ing, china Agricultural university, Beijing 100083, china 2. state key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Yangling 712.00, china 3. Geographic and Resources Management College, Yantai Normal university, Yantai 2.402., china The key laboratory of Modern {2. Agriculture System Integration Research College of Hydraulic and Civil Engineering China Agricultural University Beijing China state key {2. of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Yangling China Geographic and Resources Management College Yantai Normal University Yantai China

The soil infiltrability of hill-slope is important to such studies andpractices as hydrological process, crop water supply, irrigation practices, and soil erosion. A newmethod for measuring soil infiltrability on hill-slope under rainfall condition with run off-on-outwas advanced. Based on water (mass) balance, the mathematic models for soil infiltrability estimatedfrom the advances of runoff on soil surface and the water running out of the slope were *** of 2.cases were conducted. Case Ⅰ was done under a rainfall intensity of 2. mm/h, at aslope gradient of about 0° with a runoff/on length (area) ratio of 1 : 1. Case Ⅱ was under arainfall intensity of 60 mm/h and a slope of 2.° with a runoff/on length (area) ratio of 1 : *** ring method was also used to measure the infiltrability for comparison purposes. Theexperiments were done with soil moisture of 10%. Required data were collected from laboratoryexperiments. The infiltrability curves were computed from the experimental data. The resultsindicate that the method can well conceptually represent the transient infiltrability process, withcapability to simulate the very high initial soil infiltrability. The rationalities of the methodand the models were validated. The errors of the method for the two cases were 1.82./1.39% and4.49%/3.52.% (Experimental/Model) respectively, as estimated by comparing the rainfall amount withthe infiltrated volume, to demonstrate the accuracy of the method. The transient and steadyinfiltrability measured with double ring was much lower than those with this new method, due towater supply limit and soil aggregates breaking down at initial infiltration stage. The method canovercome the short backs of the traditional sprinkler method and double ring method for soilinfil-traility. It can be used to measure the infiltrability of sloped surface underrainfall-runoff-erosion conditions, in the related studies.

关键词： Infiltrability, runoff-on-out, rainfall, sloped surface, model.

CMM/CAD集成系统中IGES后处理器的开发

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天津大学学报（自然科学与工程技术版） 2003年第1期36卷 38-42页

作者：徐昕刘书桂天津大学精密测试技术及仪器国家重点实验室天津300072

介绍了IGES文件结构.探讨了用IGES文件作为数据交换文件开发IGES后处理器,实现CMM(三坐标测量机)与CAD集成,从而使三坐标测量机智能化.说明了将IGES文件中目录条目段和参数数据段结合起来,对不同实体类型进行不同的处理,同时对组合实体... 详细信息

介绍了IGES文件结构.探讨了用IGES文件作为数据交换文件开发IGES后处理器,实现CMM(三坐标测量机)与CAD集成,从而使三坐标测量机智能化.说明了将IGES文件中目录条目段和参数数据段结合起来,对不同实体类型进行不同的处理,同时对组合实体和结构实体做出特殊处理的提取零件信息的方法.详细讨论了从IGES文件中提取信息和构成适用于三坐标测量机系统的输入数据的处理过程.

关键词： CMM/CAD集成系统 IGES后处理器三坐标测量机 IGES文件机械制造数据交换

measuring-basis-encrypted six-state quantum {2. distribution scheme

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Progress in Natural Science:Materials International 2006年第1期16卷 84-89页

作者： CHEN Pan1, DENG Fuguo1, WANG Pingxiao1 and LONG Guilu1,2.(key laboratory for Quantum Information and Measurements and Department of Physics, Tsinghua {2., Beijing 100084, china 2. key laboratory for Atomic and Molecular NanoSciences, Tsinghua {2., Beijing 100084, china) key laboratory for Quantum Information and Measurements Department of Physics Tsinghua University Beijing 100084 China key laboratory for Atomic and Molecular NanoSciences Tsinghua University Beijing 100084 China

A six-state quantum key distribution scheme with {2.-basis encryption technique, which is based on the six-state protocol and the MBE protocol, is proposed. In this modified six-state quantum key distribution protocol, Alice and Bob use a control key to synchronize the use of their {2.-basis so that they always use the same {2.-basis. This modified six-state quantum key distribution protocol retains the advantage of higher security and at the same time has a higher efficiency.

关键词： quantum key distribution measuring-basis encrypted six-state security.

Comparison Between MIR and NIR Spectroscopic Techniques for the Determination of Fat and Protein Contents in Milk

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Transactions of tianjin university 2007年第5期13卷 375-378页

作者：张学典常敏马真彭丹徐可欣 state key {2. of precision measuring Technology and instruments Tianjin University

To compare mid-infrared(MIR)and near-infrared(NIR)spectroscopies for the determination of the fat and protein contents in milk,the same sample sets with varying concentrations of fat and protein were measured in the MIR range of 3 2.0-700 cm-1 and NIR range of 9 000-4 000 *** spectral features in the two regions were *** MIR spectra of milk were characteristic due to the MIR inherent molecular specificity,whereas the NIR spectra were relatively characterless due to the NIR low *** least squares(PLS)regression models for fat and protein were developed by using both MIR and NIR *** data with no pretreatment gave better results than NIR *** square correlation coefficient(R2.and the root mean square error of prediction(RMSEP)were 0.98 and 0.10 g/dL for fat and 0.97 and 0.11 g/dL for *** NIR techniques,satisfactory results were not obtained with raw ***,NIR data after pretreatment gave similarly good results to the ones using MIR *** paper indicates that either of the MIR and NIR spectral methods is reliable for the determination of the fat and protein contents.

关键词： mid-infrared spectroscopy near-infrared spectroscopy milk fat protein

MEMS Test System Based on Virtual Instrument Technology

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Transactions of tianjin university 2007年第2期13卷 88-92页

作者：胡晓东栗大超郭彤胡春光胡小唐 state key {2. of precision measuring Technology and instruments Tianjin University

On account of the multiformity of MEMS devices, it is necessary to integrate with some optical measurement techniques for meeting static and dynamic unit test requirements. In this paper, an automated MEMS test system is built of some commercially available components and instruments based on virtual instrument technology. The system is integrated with stroboscopic imaging, computer micro-vision, microscopic Mirau phase shifting interferometry, and laser Doppler vibrometer, and is used for the measurement of full-view in-plane and out-of-plane geometric parameters and periodical motions and single spot out-of-plane transient motion. The system configuration and measurement methods are analyzed, and some applications of the measurement of in-plane and out-of-plane dimensions and motions were described. The measurement accuracy of in-plane dimensions and out-of-plane dimensional is better than 0.2.um and 5 nm respectively. The resolution of measuring in-plane and out-of-plane motions is better than 15 nm and 2.nm respectively.

关键词： MEMS optical measurement technique stroboscopic imaging virtual instrument dynamic test

MEMS Torsion-Mirror Actuators for Optical Switching or Attenuating Applications

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光学学报 2003年第S1期23卷 141-142页

作者： Wengang Wu, Dachao Li, Yong Yuan, Guizhen Yan, Yilong Hao, Shijiu Jin institute of Microelectronics, Peking university, Beijing 100871, china, Tel: 86-10-62.57163, Fax: 86-10-62.51789,E-mail: wuwg@*** {2. key laboratory of precision measuring Technology and instruments, tianjin university, tianjin 3.0072, china Institute of Microelectronics Peking University Beijing 100871 China state key {2. of precision measuring Technology and instruments Tianjin University Tianjin 300072 China

Novel MEMS torsion-mirror actuators with monolithically integrated fiber self-holding structures are fabricated, and investigated experimentally and theoretically. Their electromechanical and optical characteristics a... 详细信息

关键词： for in on PP MEMS Torsion-Mirror Actuators for Optical Switching or Attenuating Applications of Figure

Flatness and Profile Integration Control Model for Tandem Cold Mills

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Journal of Iron and Steel Research International 2012年第3期19卷 31-37页

作者： SHAN Xiu-ying1,2.3, LIU Hong-min1,2. JIA Chun-yu1,2. SUN Jian-liang1,2.(1. Engineering Research Center of Rolling Equipment and Complete Technology of Ministry of Education, Yanshan university, Qinhuangdao 066004, Hebei, china 2. {2. key laboratory of Metastable Materials Science and Technology, Yanshan university, Qinhuangdao 066004, Hebei, china 3. Hot Tandem Rolling Factory, Jinan Iron and Steel Co Ltd, Jinan 2.0101, Shandong, china) Engineering Research Center of Rolling Equipment and Complete Technology of Ministry of Education Yanshan University Qinhuangdao Hebei China state key {2. of Metastable Materials Science and Technology Yanshan University Qinhuangdao Hebei China Hot Tandem Rolling Factory Jinan Iron and Steel Co Ltd Jinan Shandong China

Using the effective matrix methods of flatness and profile control synthetically, the flatness and profile in- tegration control scheme for tandem cold mills is built in order to increase flatness and profile control precision of tan- dem cold mills. Corresponding control strategies are adopted for various control objectives of different stands and the coordination control strategies of various stands are given, which makes the on-line flatness control cooperate with on-line profile control and implements the parallel control of different stands. According to the measured flatness and profile data of some 1550 mm tandem cold mills, the control scheme is verified and the result indicates that the scheme has high flatness and profile control precision with steady and reliable control process. A new way and method is supplied for researching shade control of tandem cold mills.

关键词： flatness profile shape effective matrix tandem cold mill

Study on Laser Visual Measurement Method for Seamless Steel Pipe Straightness Error by Multiple Line- structured Laser Sensors

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Chinese Journal of Lasers 2001年第2期 10-13页

作者： SUN Changku LIU Yue LU Rongsheng YE Shenghua (state key {2. of precision measuring Technology and instruments, tianjin university, tianjin 3.0072, china)

An original non contact measurement method using multiple line structured laser sensors is introduced for seamless steel pipe straightness error is in this paper. An arc appears on the surface of the measured seamless steel pipe against a line structured laser source. After the image of the arc is accepted by a CCD camera, the coordinates of the center of the pipe cross section circle containing the arc can be worked out through a certain algorithm. Similarly, multiple line structured laser sensors are equipped parallel to the pipe. The straightness error of the seamless steel pipe, therefore, can be inferred from the coordinates of multiple cross section centers obtained from every line structured laser sensor.

关键词： seamless steel pipe straightness error line structured laser sensor

Environmental records of lacustrine sediments in different time scales:Sediment grain size as an example

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Science china Earth Sciences 2004年第10期47卷 954-960页

作者： CHEN Jing’an1, WAN Guojiang1, David Dian Zhang2. ZHANG Feng1 & HUANG Ronggui1 1. state key {2. of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002. china 2. Department of Geography and Geology, university of Hong Kong, Pokfulam Road, Hong Kong, china state key {2. of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang China Department of Geography and Geology University of Hong Kong Hong Kong China

Sediment grain size is a conventional proxy of climatic changes. Larger sediment grain size is often interpreted to indicate dry climate during lower lake level while smaller sedi- ment grain size implies wet climate during higher lake level. Through detailed study on sediment grain sizes in Lake Erhai and Lake Chenghai, this paper reveals the different indication signifi- cances of sediment grain sizes in different time scales, different resolution investigations. For long time-scale and low resolution (102. or 103a) studies, larger sediment grain size indicates lower lake level, smaller lake area and drier climate while smaller sediment grain size indicates higher lake level, larger lake area and wetter climate. For short time-scale and high resolution (a or 10a) studies, larger sediment grain size reflects more rainfall and wetter climate while smaller sediment grain size reflects less rainfall and drier climate. Environmental information revealed by lacustrine sediment records is often different in different time scales because of the variance of sedimentation resolution, sampling resolution and dating precision. Therefore, paleoclimate im- plications of environmental proxies in long time-scale and low resolution investigations could not be mechanically applied to short time-scale and high resolution studies. Only after synthetically analyzing the influence manner and extent of all factors on the sediment records in different time scales, can credible conclusions be obtained.

关键词： lacustrine sediment, environmental record, grain size, time scale.