检索结果-内蒙古大学图书馆

conference on Advanced Global communications Technologies for Astronomy II

作者： Vestrand, WT Borozdin, K Brumby, S Casperson, D Fenimore, E Galassi, M McGowan, K Perkins, S Priedhorsky, W Starr, D White, R Wozniak, P Wren, J Los Alamos Natl Lab Los Alamos NM 87545 USA

ISBN: (纸本)0819446246

The Rapid Telescopes for Optical Response (RAPTOR) experiment is a spatially distributed system of autonomous robotic telescopes that is designed to monitor the sky for optical transients. The core of the system is composed of two telescope arrays, separated by 38 kilometers, that stereoscopically view the same 1500 square-degree field with a wide-field imaging array and a central 4 square-degree field with a more sensitive narrow-field "fovea" imager. Coupled to each telescope array is a real-time data analysis pipeline that is designed to identify interesting transients on timescales of seconds and, when a celestial transient is identified, to command the rapidly slewing robotic mounts to point the narrow-field "fovea" imagers at the transient. The two narrow-field telescopes then image the transient with higher spatial resolution and at a faster cadence to gather light curve information. Each "fovea" camera also images the transient through a different filter to provide color information. This stereoscopic monitoring array is supplemented by a rapidly slewing telescope with a low resolution spectrograph for follow-up observations of transients and a sky patrol telescope that nightly monitors about 10,000 square-degrees for variations, with timescales of a day or longer, to a depth about 100 times fainter. In addition to searching for fast transients, we will use the data stream from RAPTOR as a real-time sentinel for recognizing important variations in known sources. All of the data will be publically released through a virtual observatory called SkyDOT (Sky Database for Objects in the Time Domain) that we are developing for studying variability of the optical sky. Altogether, the RAPTOR project aims to construct a new type of system for discovery in optical astronomy-one that explores the time domain by "mining the sky in real time".

关键词： optical transients Sky monitoring real-time processing data mining robotic telescopes distributed sensors

来源：评论

学校读者我要写书评

暂无评论

Objective evaluation of segmentation quality using spatio-temporal context

Objective evaluation of segmentation quality using spatio-te...

引用

IEEE International conference on image processing

作者： A. Cavallaro E.D. Gelasca T. Ebrahimi Swiss Federal Institute of Technology Lausanne Switzerland

In this paper, we propose an automatic method for the objective evaluation of segmentation results. The method is based on computing the deviation of the segmentation results from a reference segmentation. The discrepancy between two results is weighted based on spatial and temporal contextual information, by taking into account the way humans perceive visual information. The metric is useful for applications where the final judge of the quality is a human observer or the results of segmentation are otherwise processed in a human-like fashion. The proposed evaluation has been applied both to automatically provide a ranking among different segmentation algorithms and to optimally set the parameters of a given algorithm.

关键词： image segmentation Humans Video coding Video surveillance Virtual reality Algorithm design and analysis Testing

来源：评论

学校读者我要写书评

暂无评论

Progressive image transmission over a noisy channel using wavelet transform and channel optimized vector quantization

Progressive image transmission over a noisy channel using wa...

引用

IEEE International conference on image processing

作者： J.L. Perez-Cordoba V.G. Ruiz I. Garcia Dpto. Electrónica y Tecn. Computadores Granada University Granada Spain Dpto. Arq. de Computadores y Elect Almería University Almeria Spain

This paper studies a progressive image transmission technique over waveform channels. The channel optimized vector quantization codec (COVQ) (Farvardin and Vaishampayan 1991) is applied to the image wavelet coefficients creating a robust progressive image transmission technique that mitigates the effects of a noisy channel on the reconstructed image. In order to evaluate the performance of our proposal, a Gaussian and slow-fading Rayleigh channel model, with several different values of channel signal to noise ratio (CSNR) were simulated in our experiments. Examples show a significant visual improvement of our application compared to other progressive image transmission techniques.

关键词： image communication Wavelet transforms Vector quantization Codecs Wavelet coefficients Noise robustness image reconstruction Proposals Rayleigh channels Signal to noise ratio

来源：评论

学校读者我要写书评

暂无评论

Copyright protection of images using human visual masking on DCT-based watermarking

引用

IEEE Asia-Pacific conference on Circuits and Systems

作者： Y. Rangsanseri W. Thitimajshima Department of Telecommunications Engineering Engineering King Mongkut''s Institute of Technology Ladkrabang Bangkok Thailand School of Science and Technology Bangkok University Bangkok Thailand

In this paper a new watermarking algorithm for digital images operating in the frequency domain is presented: a sequence of pseudo-random real numbers is embedded in a selected set of DCT coefficients. After embedding, the watermark is adapted to the image to be signed by exploiting the masking characteristics of the Human visual System (HVS) in order to achieve watermark invisibility without diminishing its robustness. Experimental results demonstrate that the watermark is robust to several signal processing techniques and geometric distortions.

关键词： Copyright protection Humans Watermarking Robustness Signal processing algorithms Digital images Frequency domain analysis Discrete cosine transforms visual system Signal processing

来源：评论

学校读者我要写书评

暂无评论

Mesh-based error-scalable video object codec for variable bandwidth multimedia communications

Mesh-based error-scalable video object codec for variable ba...

引用

IEEE International conference on image processing

作者： S. Tran Minh J. Benois-Pineau K. Fazekas A. Gschwindt Department of Broadband Infocommunication Systems Budapest University슠of슠Technology슠and슠Economics Budapest Hungary LABRJ UMR CNRS University of Bordeaux 1 Talence France

The work introduces a complete chain of video object compression. The process is based on an automatic extraction of video objects from raw video. The recent MPEG-4 standard philosophy, including mesh models and wavelet-based compression are involved in the scheme. Constrained Delaunay meshes are used to represent articulated video objects in a flexible manner conveying shape and motion information. The wavelet transform is applied to residual errors for scalable and efficient compression. Results on MPEG-4 test sequences for very low bitrate video communications are encouraging.

关键词： Codecs Bandwidth Multimedia communication Video compression MPEG 4 Standard Data mining Shape Wavelet transforms Testing Bit rate

来源：评论

学校读者我要写书评

暂无评论

Use Pollaczek polynomials for analysis characteristics of radar target identification system

Use Pollaczek polynomials for analysis characteristics of ra...

引用

International conference on Microwaves, Radar and Wireless communications

作者： S.N. Yarmolik S.V. Shaliapin Military Academy of Republic of Belarus Belarus Republic of Belarus Minsk Republican research and production enterprise E2809CALEVKURPE2809D Military Academy of Republic of Belarus Belarus

An analytical method of calculating the recognition characteristics of a correlated normally distributed signal against correlated normally distributed background was developed. It is based on the representation of multidimensional probability density of a set of processing channels output signal by multidimensional series of Pollaczek (1950) polynomials. This approach allows one to obtain sufficient accuracy of approximation of probability density and analytical expression for M-dimensional integrals from probability density of recognition system output signals. The advantage of this method is that it allows one to estimate recognition quality when using multidimensional portraits taking into account interchannel correlation and the difference between the distribution law of a processing channels output signal and the normal one. The result given in the article have a relatively simple form and may be used to carry out scientific engineering designs.

关键词： Polynomials Radar Signal processing Character recognition Signal analysis Target recognition Multidimensional signal processing image analysis Design engineering Signal design

来源：评论

学校读者我要写书评

暂无评论

Genre-based search through biomedical images

Proceedings - International Conference on Pattern Recognitio...

引用

Proceedings - International conference on Pattern Recognition 2002年第1期16卷 271-273页

作者： Geusebroek, Jan-Mark Hoang, Minh Anh Van Gemert, Jan Worring, Marcel Intelligent Sensory Information Systems Faculty of Science University of Amsterdam Kruislaan 403 1098 SJ Amsterdam Netherlands

We exploit the retrieval of visual information from biomedical scientific publication databases. Therefore, we consider the use of domain specific genres to automatically subdivide large image databases into smaller, consistent parts. Combination with Latent Semantic Indexing on the picture captions allows for efficient retrieval of images in specific categories. We demonstrate our approach on a large collection of images with captions from the Elsevier Brain Research publications. Initial result demonstrate the power of the proposed combination. © 2002 IEEE.

关键词： image processing

来源：评论

学校读者我要写书评

暂无评论

Energy efficient wireless video communications for the digital set-top box

Energy efficient wireless video communications for the digit...

引用

IEEE International conference on image processing

作者： Y. Eisenberg C.E. Luna T.N. Pappas R. Berry A.K. Katsaggelos Department of Electrical and Computer Engineering Northwestern University Evanston IL USA

In the future, digital set-top boxes may serve as the primary access point for wireless home networks, enabling mobile users to use videoconferencing as well as streaming applications on hand-held devices. In this scenario, an important issue that must be addressed is the limited energy supply of a mobile device. This is of course a relevant issue for any wireless device. We focus on methods for efficiently utilizing transmission energy in wireless video communications. We present a general framework for the problem of minimizing the transmission energy required to provide an acceptable level of video quality. We discuss two special cases in which communication resources are adjusted simultaneously with the source coding parameters in order to provide (i) packet loss adaptation and (ii) transmission rate adaptation.

关键词： Energy efficiency Wireless communication Videoconference Source coding Propagation losses Delay Streaming media Mobile communication Wireless networks Video sequences

来源：评论

学校读者我要写书评

暂无评论

A weighted linear prediction method for near-field source localization

A weighted linear prediction method for near-field source lo...

引用

International conference on Acoustics, Speech, and Signal processing (ICASSP)

作者： Emmanuèle Grosicki Karim Abed-Meraim Laboratorie Traitement du Signal et de l'image Ecole Nationale Supérieure des TéIécommunications France

This paper deals with the near field source localization problem using the array output second order statistics (SOS). The range and angle parameters are estimated through a weighted linear prediction (LP) algorithm applied to a properly chosen array output correlation sequence. Detailed performance analysis and derivation of the optimal weightings are provided. Simulation results are finally presented to validate the theoretical analysis results and to assess the performance of the proposed method.

关键词： Logic gates Silicon

来源：评论

学校读者我要写书评

暂无评论

Optimal caching mechanism for JPEG 2000 communications

Optimal caching mechanism for JPEG 2000 communications

引用

European Signal processing conference (EUSIPCO)

作者： Marcela Iregui Philippe Chevalier Benoît Macq POMS unit Université Catholique de Louvain Belgium

In this paper we study an optimal transmission mechanism along with a memory caching strategy in a server-client architecture for large JPEG2000 (J2K) images browsing. The system takes advantage on the scalability introduced by J2K codestreams. The idea is that users accessing the server could navigate in a seamless way in one or several images. They could change the displaying requirements, ask for a desired resolution, quality or region of interest (ROI) with no need to receive the whole codestream. We propose a smart data streaming strategy to minimize the latency time and support interactive browsing. Our strategy takes into account several constraints as delays, memory, bandwidth, etc., for permitting fast adaptation to image browsing with optimal employment of resources.

关键词： image resolution Transform coding Abstracts Electronic mail Bismuth Programming Decoding

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：