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Target rotation parameter estimation for ISAR imaging via frame processing

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红外与激光工程 2016年第3期45卷 7-17页

作者： Xuezhi Wang Yajing Huang Weiping Yang bill moran School of Electrical and Computer Engineering RMIT University School of Electronic Science and Engineering National University of Defense Technology

Frame processing method offers a model-based approach to Inverse Synthetic Aperture Radar(ISAR) imaging. It also provides a way to estimate the rotation rate of a non-cooperative target from radar returns via the frame operator properties. In this paper, the relationship between the best achievable ISAR image and the reconstructed image from radar returns was derived in the framework of Finite Frame Processing theory. We show that image defocusing caused by the use of an incorrect target rotation rate is interpreted under the FP method as a frame operator mismatch problem which causes energy dispersion. The unknown target rotation rate may be computed by optimizing the frame operator via a prominent point. Consequently, a prominent intensity maximization method in FP framework was proposed to estimate the underlying target rotation rate from radar returns. In addition, an image filtering technique was implemented to assist searching for a prominent point in practice. The proposed method is justified via a simulation analysis on the performance of FP imaging versus target rotation rate *** of the proposed method is also confirmed from real ISAR data experiments.

关键词： ISAR imaging frame theory frame processing target rotation rate radar waveforms

Taking the pulse of a plant:dynamic laser speckle analysis of plants

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红外与激光工程 2016年第9期45卷 7-18页

作者： Zhong Xu Wang Xuezhi Cooley Nicola Farrell Peter moran bill Department of Infrastructure Engineering University of Melbourne School of Electrical and Computer Engineering Royal Melbourne Institute Technology Higher Education-Primary Industy NMIT and Melbourne PolytechnicNMIT Epping Campus Department of Electrical and Electronic Engineering University of Melbourne

Ideally, to achieve optimal production in agriculture, crop stress needs to be measured in real-time, and plant inputs managed in response. However, many important physiological responses like photosynthesis are difficult to measure, and current trade-offs between cost, robustness, and spatial measurement capacity of available plant sensors may prevent practical in-field application of most current sensing techniques. This paper investigates a novel application of laser speckle imaging of a plant leaf as a sensor with an aim, ultimately, to detect indicators of crop stress: changes to the dynamic properties of leaf topography on the scale of the wavelength of laser light. In our previous published work, an initial prototype of the laser speckle acquisition system specific for plant status measurements together with data processing algorithms were developed. In this paper, we report a new area based statistical method that improves robustness of the data processing against disturbances from various sources. Water and light responses of the laser speckle measurements from cabbage leaves taken by the developed apparatus are exhibited via growth chamber experiments. Experimental evidence indicates that the properties of the laser speckle patterns from a leaf are closely related to the physiological status of the leaf. This technology has the potential to be robust, cost effective, and relatively inexpensive to scale.

关键词：磁光阵列光存储融合存储

Modeling and Classifying Surface Roughness via Laser Speckle Statistics

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Modeling and Classifying Surface Roughness via Laser Speckle...

2011 World Congress on Engineering and Technology(CET 2011)

作者： Peter Farrell bill moran Department of Electrical ＆ Electronic Engineering University of MelbourneAustralia

Laser speckle interferometry can be used to classify roughness level of a randomly textured surface,where the performance of classification is dominated by the statistical method *** this paper,a simulation model of laser speckle patterns based on coherent electromagnetic wave scattering from a purely randomly textured surface under various roughness levels is described and *** model enables efficient simulation methods to be used for the study of statistical properties of laser speckle patterns and understanding the relationship between speckle statistics and surface *** addition,an autocorrelation based analysis method is proposed to summarise the statistical signatures of various roughness levels parameterised by the amplitude of a Gaussian random *** presented statistical results,which are computed using simulated laser speckle patterns under two different measurement scenarios,show a consistent agreement with *** proposed analysis method is also demonstrated to be capable to accurately discriminate roughness class of a surface.

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来源： cnki会议评论

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利用红外成像技术的自动树冠温度估计

红外与激光工程 2011年第1期40卷 169-175页

作者：杨卫平王学知比尔.莫兰张焱张志龙阿什利.惠顿尼古拉.库尔利国防科技大学电子科学与工程学院湖南长沙410073 墨尔本大学电气与电子工程系墨尔本大学土地与环境学院

使用红外热像仪获取待测树冠图像,将树冠的光学图像与之配准,可采用彩色识别技术得到树叶的温度分布。这种处理的成功依赖于红外与光学图像配准,以及树叶区域精确提取的假设。实际上,简单的颜色识别算法无法正常工作。为此,提出了一种... 详细信息

使用红外热像仪获取待测树冠图像,将树冠的光学图像与之配准,可采用彩色识别技术得到树叶的温度分布。这种处理的成功依赖于红外与光学图像配准,以及树叶区域精确提取的假设。实际上,简单的颜色识别算法无法正常工作。为此,提出了一种新方法来解决温度的估计问题。潜在的树叶温度分布可以认为是两个可分离的温度密度的融合,结合颜色识别与高斯混合分布提取技术来对颜色进行识别。随后采用N-均值方法从估计的树叶温度分布中估计出参考树叶的温度,实验结果证明了算法的有效性。

关键词：树冠温度估计作物水应力指数(CWSI) 高斯混合分类数据融合颜色识别

Development of a six drillhead roof bolting machine

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International Journal of Mining Science and Technology 2017年第1期27卷 37-41页

作者： Kyslinger bill A. J.H.Fletcher&Co. HuntingtonWV25722USA

In underground mining, machine design is predominantly dictated by mine conditions and individual customer desires. In partnership with Foresight Energy, J. H. Fletcher & Company was tasked to design and manufacture a new roof bolting machine with six independent drilling apparatus on board capable of drilling and bolting the roof and ribs with material handling. The objective was to produce a machine capable of drilling and installing six bolts simultaneously with a limited number of operators. The goal of the mine is to decrease the time to bolt a cut to improve the safety level of the current roof bolting method, improve efficiency and to improve the bottom line cost of entry development. The customer wanted four drills at the front of the machine dedicated to installing roof bolts and then another two drills behind them dedicated to rib bolts. This dictated the requirement of latched controls, which would allow the operator to start drilling one hole and then latch the controls to be able to move on to the *** result of the design is a machine with a single platform and six independent masts with drillheads:four masts strictly for drilling and installing roof bolts on the front of the platform and two masts on the back of the platform for rib bolts. The controls at each operator's station include a latch control for drilling. The six-head roof bolter allows fewer operators to drill and install roof and rib bolts, which in turn lowers the miners' roof exposure per cut. This design reduces the operator's exposure from the inherent pinch points and rotary hazards once he has engaged the latch drilling. Therefore, the machine will help to decrease the time to bolt a cut, improving productivity while enhancing the ability to operate the machine safely.

关键词： Roof bolter MiningSix-head FletcherLatched Material handling

Design and analyses of open-ended pipe piles in cohesionless soils

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Frontiers of Structural and Civil Engineering 2016年第1期10卷 22-29页

作者： Yuan GUO Xiong (bill) YU Department of Civil Engineering Case Western Reserve University 2104 Adelbert Road Bingham 260 Cleveland OH 44106-7201USA

Large open-ended pipe pile has been found to be advantageous for use in transportation projects. The current design method, however, is not adequately developed. To close this practice gap, this paper first summarized different design methods for open-ended pipe piles in sandy soils. A major factor for all the design codes is to properly account for the formation and effects of soil plug. The comparison indicates that there is a large variation in the base capacity evaluation among different methods due to the complex behaviors of soil plug. To close the knowledge gap, discrete element method （DEM） was used to simulate the soil plugging process and provide insight on the plugging mechanism. The simulation results show that the arching effect significantly increases the internal unit shear resistance along pipe piles. The porosity distribution and particle contact force distribution from DEM model indicate a large stress concentration occurs at the bottom of the soil plug. Besides, nearly 90% of the plug resistance is provided by the bottom half portion of the soil column. The soil-pile friction coefficient has a significant effect on the magnitude of plug resistance, with the major transition occurred for friction coefficient between 0.3 and 0.4.

关键词： open-ended pipe pile soil plug DEM base capacity

Image analyses for video-based remote structure vibration monitoring system

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Frontiers of Structural and Civil Engineering 2016年第1期10卷 12-21页

作者： Yang YANG Xiong (bill) YU Department of Electrical Engineering and Computer Science Case Western Reserve University 10900 Euclid Avenue Bingham203d Cleveland OH 44106-7201 USA Department of Civil Engineering Case Western Reserve University 10900 Euclid Avenue Bingham 210 Cleveland OH 44106-7201 USA

Video-based vibration measurement is a cost-effective way for remote monitoring the health conditions of transportation and other civil structures, especially for situations where accessibility is restricted and does not allow installation of conventional monitoring devices. Besides, video-based system is global measurement. The technical basis of video-based remote vibration measurement system is digital image analysis. Comparison of the images allow the field of motion to be accurately delineated. Such information is important to understand the structure behaviors including the motion and strain distribution. This paper presents system and analyses to monitor the vibration velocity and displacement field. The performance is demonstrated on a testbed of model building. Three different methods （i.e., frame difference method, particle image velocimetry, and optical Flow Method） are utilized to analyze the image sequences to extract the feature of motion. The Performance is validated using accelerometer data. The results indicate that all three methods can estimate the velocity field of the model building, although the results can be affected by factors such as background noise and environmental interference. Optical flow method achieved the best performance among these three methods studied. With further refinement of system hardware and image processing software, it will be developed into a remote video based monitoring system for structural health monitoring of transportation infrastructure to assist the diagnoses of its health conditions.

关键词： structure health monitoring velocity estimation frame difference PIV optical-flow method

Physical science bill W. Tillery.

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2002年

作者： bill W. Tillery.

来源：畅想之星图书光盘版（南... 评论

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