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Temperature and Water Vapor weighting functions from Radiative Transfer Equation with Surface Emissivity and Solar Reflectivity

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Advances in Atmospheric Sciences 1994年第4期11卷 421-426页

作者：李俊 Cooperative Institute for Meteorological Satellite Studies Space Science and Engineering Center University of Wisconsin-Madison. Madison WI 53706 U.S.A.

Linearization of Radiative Transfer Equation (RTE) is the key step in physical retrieval of atmospheric temperature and moisture profiles from InfRared (IR) sounder observations. In this paper, the successive forms of temperature and water vapor mixing ratio component weighting functions are derived by applying one term variation method to RTE with surface emissivity and solar reflectivity contained. Retrivals of temperature and water vapor mixing ratio profiles from simulated Atmospheric Infrared Sounder (AIRS) observations with surface emissivity and solar reflectivity are presented.

关键词： Radiative Transfer Equation weighting function Retrieval

Impact localization of composite laminates based on weight function compensation localization algorithm of thin film sensors

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International Journal of Smart and Nano Materials 2023年第2期14卷 139-154页

作者： Ying Wang Hongmei Li Shaowei Lu Xingmin Liu Wei Li Xiaoqiang Wang Lu Zhang Qingxuan Wang College of Aerospace Engineering Shenyang Aerospace University(SAU)ShenyangChina College of Material Science and Engineering Shenyang Aerospace University(SAU)ShenyangChina

Composite structures are sensitive to impact damage in practical *** resistance change method(ERCM)is an ideal technique for damage monitoring of composite *** to the anisotropy of fiber-resin matrix composites,impact location monitoring is difficult,and research on impact location of fiber composite laminates(FRPs)is limited.A preparation method of MXene/CNT/CuNps thin film sensor is *** to the modeling simulation and theoretical calculation,the resistance change characteristics of the thin film sensor are obtained,the relationship between the impact distance and the resistance change is established,and the sensor array is designed.A three-point localization algorithm and a weight function compensation localization algorithm are proposed,which can improve the imaging accuracy of the impact *** impact point location was observed and analyzed using ultrasonic C-scan *** results show that the weight function compensation positioning algorithm can accurately locate the impact of the composite structure,and the error in the X direction is 7.1%,the error in the Y direction is 0.03%,which verifies the effectiveness of the method.

关键词： Electric resistance change method Mxene/CNT/CuNps film sensor damage localization weighting function

Dust collector localization in trouble of moving freight car detection system

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第2期14卷 98-106页

作者： Fu-qiang ZHOU Rong ZOU He GAO School of Instrumentation Science and Optoelectronics Engineering Beihang University

For a long time,trouble detection and maintenance of freight cars have been completed manually by *** realize the transition from manual to computer-based detection and maintenance,we focus on dust collector localization under complex conditions in the trouble of moving freight car detection *** mid-level features which are also named flexible edge arrangement(FEA) features,we first build the edge-based 2D model of the dust collectors,and then match target objects by a weighted Hausdorff distance *** difference is that the constructed weighting function is generated by the FEA features other than specified subjectively,which can truly reflect the most basic property regions of the 3D *** results indicate that the proposed algorithm has better robustness to variable lighting,different viewing angle,and complex texture,and it shows a stronger adaptive *** localization correct rate of the target object is over 90%,which completely meets the need of practical applications.

关键词： Hausdorff distance weighting function Trouble detection Rail transportation

Frequency-dependent friction in pipelines

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Chinese Physics B 2015年第3期24卷 230-236页

作者：蒋丹李松晶杨平赵天扬 School of Mechatronics Engineering University of Electronic Science and Technology of China School of Mechatronics Engineering Harbin Institute of Technology

A comprehensive study of modeling the frequency-dependent friction in a pipeline during pressure transients following a sudden cut-off of the flow is presented. A new method using genetic algorithms（GAs） for parameter identification of the weighting function coefficients of the frequency-dependent friction model is described. The number of weighting terms required in the friction model is obtained. Comparisons between simulation results and experimental data of transient pressure pulsations close to the valve in horizontal upstream and downstream pipelines are carried out *** validity of the parameter identification method for weighting function coefficients and the calculation method for the number of weighting terms in the friction model is confirmed.

关键词： frequency-dependent friction pipeline pressure transients weighting function

Simultaneous　Non-linear　Retrieval　of　Atmospheric　Temperature　and　Absorbing　Constituent　Profiles　from　Satellite　Infrared　Sounder　Radiances

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Advances in Atmospheric Sciences 1994年第2期11卷 128-138页

作者：李俊周风仙曾庆存 1. Academia Sinica Institute of Atmospheric Physics 100029 Beijing

Based on Zeng's theory (1974), a successive linearized form of radiative transfer equation (RTE) is derived for simultaneous retrieval of atmospheric temperature and absorbing constituent profiles from satellite infrared observations. It contains the temperature component weighting function and absorbing constituent (HZO, O3, CH4 etc.) component weighting functions. All these weighting functions reach maximum at their own 'optimum information levels', and make the remote sensing equations well-conditional. Then the atmospheric profiles are derived by Newton'snon-linear iteration method. Experiments of retrieval from both TIROS-N operational High Resolution infrared Sounder (HIRS) and the simulated Atmospheric infRared Sounder (AIRS) show an significant improvement.

关键词： Sounding weighting function Retrieval

H_∞ Autopilot Design for Autonomous Underwater Vehicles

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Journal of Shanghai Jiaotong university(Science) 2010年第2期15卷 194-198页

作者：冯正平 R. ALLEN School of Naval Architecture Ocean and Civil EngineeringShanghai Jiaotong University Institute of Sound and Vibration Research University of SouthamptonSouthampton SO17 1BJUnited Kingdom

The design approach of H∞ autopilot for autonomous underwater vehicles (AUVs) is proposed. Comprised by the three sub-controllers,i.e. speed,heading and depth controllers,the designed autopilot has advantage over existing H∞ control of AUVs. The overshoot in speed,heading and depth control systems under step commands is restricted by refining the weighting function for robust stability. The dynamic performance of heading and depth control systems is improved by feeding back yaw rate and pitch angle,respectively. To evaluate the design approach,it is then utilized to synthesize the autopilot for flight control of Subzero Ⅲ,a low cost test-bed for AUV control techniques. Both simulations and water trails verify the effectiveness of the design approach.

关键词： autonomous underwater vehicle (AUV) autopilot H∞ control weighting function

Comparison of two gap-metric-based weighting methods in multilinear model control 36

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Comparison of two gap-metric-based weighting methods in mult...

Trajectory Control: Directional MWD Inversely New Wellbore Positioning Accuracy Prediction Method

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作者： Jingjing Du College of Internet of Things Engineering Hohai Universtiy

ISBN: (纸本)9781538629185

A 1/δ gap metric based weighting method is proposed for multilinear model control of nonlinear systems, in which the gap metric is employed to formulate weighting functions for local controller combination. Comparisons between the proposed weighting method and another 1-δ gap metric based weighting method have been made. A CSTR system is studied to demonstrate the effectiveness of the proposed weighting method. Simulations demonstrate that the proposed weighting method has all the advantages of the 1-δ weighting method. But it is more effective than the 1-δ gap weighting method, and more sensitive to the tuning parameters, making it much easier to apply.

关键词： multilinear model control gap metric weighting function nonlinear system

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Journal of China University of Geosciences 2004年第4期15卷 425-433页

作者： Ahmed Abd Alaziz Ibrahim Tagwa Ahmed Musa Faculty of Engineering China University of Geosciences Wuhan 430074 China Engineering Faculty Sudan University of Science and Technology Sudan Faculty of Earth Resources China University of Geosciences Wuhan 430074 China Engineering Faculty Sudan University of Science and Technology Sudan

The deviation control of directional drilling is essentially the controlling of two angles of the wellbore actually drilled, namely, the inclination and azimuth. In directional drilling the bit trajectory never coincides exactly with the planned path, which is usually a plane curve with straight, building, holding, and dropping sections in succession. The drilling direction is of course dependant on the direction of the resultant forces acting on the bit and it is quite a tough job to hit the optimum target at the hole bottom as required. The traditional passive methods for correcting the drilling path have not met the demand to improve the techniques of deviation control. A method for combining wellbore surveys to obtain a composite, more accurate well position relies on accepting the position of the well from the most accurate survey instrument used in a given section of the wellbore. The error in each position measurement is the sum of many independent root sources of error effects. The relationship between surveys and other influential factors is considered, along with an analysis of different points of view. The collaborative work describes, establishes a common starting point of wellbore position uncertainty model, definition of what constitutes an error model, mathematics of position uncertainty calculation and an error model for basic directional service.

关键词： wellbore trajectory bit trajectory actual/planned path steerable directional tool measurement while drilling (MWD) logging while drilling (LWD) position uncertainty error accuracy prediction weighting function

关于矿体指标兼顾已知点距离与方向权函数估计方法的研究

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有色金属 1991年第3期43卷 7-11页

作者：汪云甲中国矿业大学

本文提出了一套新的估值权函数,这种权函数既考虑了已知点的分布状态,又考虑到了矿体指标的空间特性。通过相当多的实例计算与计算机模拟,得到了一些重要结论。

关键词： Orebody indexes(geological variables) weighting function Estimate Computer simulation