检索结果-内蒙古大学图书馆

Formulation and validation of simulated data for the Atmospheric Infrared Sounder (AIRS)

IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 2003年第2期41卷 314-329页

作者： Fishbein, E Farmer, CB Granger, SL Gregorich, DT Gunson, MR Hannon, SE Hofstadter, MD Lee, SY Leroy, SS Strow, LL CALTECH Jet Prop Lab Pasadena CA 91109 USA Univ Maryland Baltimore Cty Dept Phys Baltimore MD 21205 USA

Models for synthesizing radiance measurements by the Atmospheric Infrared Sounder (AIRS) are described. Synthetic radiances have been generated for developing and testing data processing algorithms. The radiances are calculated from geophysical states derived from weather forecasts and climatology using the AIRS rapid transmission algorithm. The data contain horizontal variability at the spatial resolution of AIRS from the surface and cloud fields. This is needed to test retrieval algorithms under partially cloudy conditions. The surface variability is added using vegetation and International Geosphere Biosphere Programme surface type maps, while cloud variability is added randomly. The radiances are spectrally averaged to create High Resolution Infrared Sounder (HIRS) data, and this is compared with actual HIRS2 data on the NOAA 14 satellite. The simulated data underrepresent high-altitude equatorial cirrus clouds and have too much local variability. They agree in the mean to within 1-4 K, and global standard deviation agrees to better than 2 K. Simulated data have been a valuable tool for developing retrieval algorithms and studying error characteristics and will continue to be so after launch.

关键词： algorithm development atmospheric retrieval cloud scene modeling data simulation High Resolution Infrared Sounder (HIRS) satellite remote sensing

来源：评论

学校读者我要写书评

暂无评论

Tracking a convoy of multiple targets using acoustic sensor data

Tracking a convoy of multiple targets using acoustic sensor ...

引用

Conference on Acquisition, Tracking, and Pointing XVII

作者： Damarla, TR USA Res Lab Acoust Signal Proc Branch AMSRL SE SA Adelphi MD 20783 USA

ISBN: (纸本)0819449415

In this paper we present an algorithm to track a convoy of several targets in a scene using acoustic sensor array data. The tracking algorithm is based on template of the direction of arrival (DOA) angles for the leading target. Often the first target is the closest target to the sensor array and hence the loudest with good signal to noise ratio. Several steps were used to generate a template of the DOA angle for the leading target, namely, (a) the angle at the present instant should be close to the angle at the previous instant and (b) the angle at the present instant should be within error bounds of the predicted value based on the previous values. Once the template of the DOA angles of the leading target is developed, it is used to predict the DOA angle tracks of the remaining targets. In order to generate the tracks for the remaining targets, a track is established if the angles correspond to the initial track values of the first target. Second the time delay between the first track and the remaining tracks are estimated at the highest correlation points between the first track and the remaining tracks. As the vehicles move at different speeds the tracks either compress or expand depending on whether a target is moving fast or slow compared to the first target. The expansion and compression ratios are estimated and used to estimate the predicted DOA angle values of the remaining targets. Based on these predicted DOA angles of the remaining targets the DOA angles obtained from the MVDR or Incoherent MUSIC will be appropriately assigned to proper tracks. Several other rules were developed to avoid mixing the tracks. The algorithm is tested on data collected at Aberdeen Proving Ground with a convoy of 3, 4 and 5 vehicles. Some of the vehicles are tracked and some are wheeled vehicles. The tracking algorithm results are found to be good. The results will be presented at the conference and in the paper.

关键词： Sensors Detection and tracking algorithms Acoustics algorithm development Signal processing Data processing Signal to noise ratio Neodymium Analytical research Target acquisition

来源：评论

学校读者我要写书评

暂无评论

Multilevel test and validation of algorithms implemented in a SOPC VisionNode

Multilevel test and validation of algorithms implemented in ...

引用

Conference on Intelligent Robots and Computer Vision XXI

作者： Sluiter, A Hartmann, K Hasenmaier, B Rost, M Stieler, D Weihs, W Univ Siegen Ctr Sensor Syst D-57076 Siegen Germany

ISBN: (纸本)081945155X

This paper describes results of a tool development process and still on-going research program in multilevel algorithm design and validation for multisensor systems. Our work covers both the algorithm design process including the simulation efforts and the implementation of the algorithms into the sensor node prepared for real-time processing within a vision system network. The sensor node hardware is based on the System on Programmable Chip (SOPC)-Technology. This gives us the flexibility to interface different kinds of sensor elements (matrix-, line-sensors) and the processing-power to provide real-time possibilities in height data-rate applications. At the point today our hardware module for Vision applications also uses a CPU module. This results in a high flexibility concerning the communication efforts. Our design can provide the use of CPU-modules within the SOPC design also. Mapping algorithms into a distributed sensor network will be done in either a centralized or decentralized way. That means the algorithm will be running on one sensor node or a part of the algorithm is implemented on some others nodes within the network. Beginning at the design and simulation level different kind of levels are opened for optimization, test and validate the developed algorithm. We present the architectural framework that supports the multilevel test and validation process.

关键词： algorithm development Simulink Sensors Field programmable gate arrays Detection and tracking algorithms MATLAB Computer architecture Computer simulations Data communications Image processing

来源：评论

学校读者我要写书评

暂无评论

Wavelets analysis for the fast integration and derivation of a class of signals related to control systems

Wavelets analysis for the fast integration and derivation of...

引用

Wavelets - Applications in Signal and Image Processing X Conference

作者： Ageyev, A Gandelli, A Politecn Milan Dipartimento Elettrotecn I-20133 Milan Italy

ISBN: (纸本)0819450804

Wavelet transform is a powerful and useful mathematical tool for signal processing. In this paper detailed description of procedures for numerical integration and derivation in Haar domain has been done. These procedures are necessary both in control systems analysis, and, especially, for control design and development. A detailed comparison between classical methods of evaluation and the Haar way is presented and critically discussed.

关键词： Wavelet transforms Control systems Control systems design Wavelets Signal processing algorithm development Image processing Matrices Numerical integration Integration

来源：评论

学校读者我要写书评

暂无评论

Energy flux method for inspection of contact and VIA layer reticles

Energy flux method for inspection of contact and VIA layer r...

引用

Conference on Metrology, Inspection, and Process Control for Microlithography XVII

作者： Garcia, H Volk, W Xiong, YL Watson, S Yu, ZC Guo, Z Wang, LT KLA Tencor San Jose CA 95134 USA

ISBN: (纸本)0819448435

Contacts and VIAs are features whose integrity are very susceptible to reticle CD defects or in general, to defects that produce a change of total energy (flux) projected through the reticle. As lithography is extended beyond the 130nm node, the problem becomes more critical. Detecting and analyzing photomask critical dimension (CD) errors and semitransparent defects is vital for qualifying reticles to enable high IC wafer yield for the 90nm node. The current state of the art inspection methods are unable to meet the industry requirements for contact and via features. Using the TeraStar(TM) pattern inspection system's image computer platform, a new algorithm, TeraFlux(TM), has been implemented and tested for the inspection of small "closed" features. The algorithm compares the transmitted energy flux difference between a test contact (or a group of contacts) and a reference image for small closed features, such as, contacts, trenches, and cells on chrome and half-tone reticles. The algorithm is applicable to both clear and dark field reticles. Sensitivity characterization tests show that the new algorithm provides CD error detection to 6% energy flux variation with low false defect counts. We performed experiments to correlate the sensitivity performance of the new algorithm with wafer printability results. The results will be presented together with results of inspections results of programmed defect plates and production reticles.

关键词： Inspection Reticles Defect detection Critical dimension metrology Semiconducting wafers Image segmentation Lithography algorithm development Defect inspection Detection and tracking algorithms

来源：评论

学校读者我要写书评

暂无评论

Angle-based band selection for material identification in hyperspectral processing

Angle-based band selection for material identification in hy...

引用

Conference on algorithms and Technologies for Multispectral, Hyperspectral, and Ultraspectral Imagery IX

作者： Keshava, N MIT Lincoln Lab Lexington MA 02420 USA

ISBN: (纸本)0819449539

In this article we present a method for hyperspectral band selection that yields superior classification results while only using a subset of the available bands. The approach originates from a comprehensive physical and mathematical understanding of the distance metrics used to compare hyperspectral signals, and it exploits an exact decomposition of a common metric, the Spectral Angle Mapper (SAM), to select bands which increase the angular contrast between target classes. Using real spectroradiometer and sensor data collected by the HYDICE sensor, the technique significantly improves the discrimination performance for two spectrally similar classes, while using only a fraction of the available bands. The approach is extended to a hierarchical architecture for material identification using spectral libraries that is shown to outperform the traditional angle-based classifier which employs all available bands. Consequently, better material identification performance can be achieved using significantly fewer bands, thus introducing dramatic benefits for the design and utilization of spectral libraries.

关键词： Reflectivity Sensors Dimension reduction Baryon acoustic oscillations Optimization (mathematics) Binary data Distance measurement Detection and tracking algorithms algorithm development Pattern recognition

来源：评论

学校读者我要写书评

暂无评论

Multichannel modal liquid crystal wavefront corrector

Multichannel modal liquid crystal wavefront corrector

引用

19th Congress of the International-Commission-for-Optics

作者： Kotova, SP Clark, P Guralnik, IR Klimov, NA Kvashnin, MY Langlois, M Loktev, MY Love, GD Naumov, AF Rakhmatulin, MA Saunter, CJ Vdovin, GV Zayakin, OA Russian Acad Sci PN Lebedev Phys Inst Samara Branch Samara 443011 Russia

37-channel modal liquid crystal wavefront correctors with a 30 and 80 mm diameter aperture are developed. Optical response, voltage-phase and dynamic properties of the devices have been studied. The possibility of syn... 详细信息

ISBN: (纸本)0819445967

关键词： Wavefronts Liquid crystals Electrodes Monochromatic aberrations algorithm development Astronomy Interferometers Reflectivity Electronics Roads

来源：评论

学校读者我要写书评

暂无评论

Embedded real-time image processing hardware for feature extraction and clustering

Embedded real-time image processing hardware for feature ext...

引用

Conference on Acquisition, Tracking, and Pointing XVII

作者： Chiu, LH Chang, G PRINTRONIX INC Irvine CA USA

ISBN: (纸本)0819449415

Printronix, Inc. uses scanner-based image systems to perform print quality measurements for line-matrix printers. The size of the image samples and image definition required make commercial scanners convenient to use. The image processing is relatively well defined, and we are able to simplify many of the calculations into hardware equations and V code. The process of rapidly prototyping the system using DSP based 'c' code gets the algorithms well defined early in the development cycle. Once a working system is defined. the rest of the process involves splitting the task Lip for the FPGA and the DSP implementation. Deciding which of the two to use. the DSP or the FPGA, is a simple matter of trial benchmarking. There are two kinds of benchmarking: One for speed, and the other for memory. The more memory intensive algorithms should run in the DSP, and the simple real time tasks can use the FPGA most effectively. Once the task is split, we can decide which platform the algorithm should be executed. This involves prototyping all the code in the DSP, then timing various blocks of the algorithm. Slow routines can be optimized using the compiler tools. and if further reduction in time is needed, into tasks that the FPGA can perform.

关键词： Digital signal processing Field programmable gate arrays Image segmentation Feature extraction Image quality Image processing algorithm development Printing Prototyping Real time image processing

来源：评论

学校读者我要写书评

暂无评论

Regularization in the synthesis of host-based anomaly detectors

Regularization in the synthesis of host-based anomaly detect...

引用

Conference on System Diagnosis and Prognosis: Security and Condition Monitoring Issues III

作者： Michael, CC Cigital Labs Sterling VA 20166 USA

ISBN: (纸本)0819449679

The goal of host-based intrusion detection is to detect attacks against a sin-le information system. Many host-based intrusion detector systems - especially those that use anomaly detection - use training data to synthesize detectors automatically, that is, the detectors are classifiers created by machine learning algorithms. Regularization, which often improves the performance of machine learning algorithms, has not previously been applied to intrusion detector synthesis. This paper discusses regularization for machine learning-based intrusion detectors, showing how regularization can be accomplished for such systems and providing the results of an empirical evaluation.

关键词： Sensors Detection and tracking algorithms Machine learning Computer intrusion detection Databases algorithm development Evolutionary algorithms Error analysis Statistical analysis Computing systems

来源：评论

学校读者我要写书评

暂无评论

K-Means Re-Clustering - algorithmic options with quantifiable performance comparisons

K-Means Re-Clustering - algorithmic options with quantifiabl...

引用

Conference on Optical Engineering at the Lawrence-Livermore-National-Laboratory

作者： Meyer, A Paglieroni, D Astaneh, C Lawrence Livermore Natl Lab Livermore CA 94550 USA

ISBN: (纸本)081944801X

This paper presents various architectural options for implementing a K-Means Re-Clustering algorithm suitable for unsupervised segmentation of hyperspectral images. Performance metrics are developed based upon quantitative comparisons of convergence rates and segmentation quality. A methodology for making these comparisons is developed and used to establish K values that produce the best segmentations with minimal processing requirements. Convergence rates depend on the initial choice of cluster centers. Consequently, this same methodology may be used to evaluate the effectiveness of different initialization techniques.

关键词： Image segmentation Expectation maximization algorithms Image processing algorithms and systems algorithm development Image quality Spectral resolution Hyperspectral imaging Image classification Quantization Image processing

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：