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DCC 2005: data Compression Conference

作者： Huang, Bormin Ahuja, Alok Huang, Hung-Lung Schmit, Timothy J. Heymann, Roger W. Cooperative Institute for Meteorological Satellite Studies University of Wisconsin-Madison Madison WI 53706 United States NOAA National Environmental Satellite Data and Information Service Office of Research and Applications Madison WI 53706 United States NOAA National Environmental Satellite Data and Information Service Office of Systems Development Silver Spring MD 20910 United States

The compression of three-dimensional ultraspectral sounder data is a challenging task given its unprecedented size. We develop a fast precomputed vector quantization (FPVQ) scheme with optimal bit allocation for lossless compression of ultraspectral sounder data. The scheme consists of linear prediction, bit-depth partitioning, vector quantization, and optimal bit allocation. Linear prediction serves as a whitening tool to make the prediction residuals of each channel close to a Gaussian distribution, and then these residuals are partitioned based on bit depths. Each partition is further divided into several sub-partitions with various 2k channels for vector quantization. Only the codebooks with 2m codewords for 2 k-dimensional normalized Gaussian distributions are precomputed. A new algorithm is developed for optimal bit allocation among subpartitions. Unlike previous algorithms [19, 20] that may yield a sub-optimal solution, the proposed algorithm guarantees to find the minimum of the cost function under the constraint of a given total bit rate. Numerical experiments upon the NASA AIRS data show that the FPVQ scheme gives high compression ratios for lossless compression of ultraspectral sounder data. © 2005 IEEE.

关键词： data compression

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Appearance modeling under geometric context

Appearance modeling under geometric context

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International Conference on Computer Vision (ICCV)

作者： Jian Li S.K. Zhou R. Chellappa Center for Automation Research & ECE Department University of Maryland College Park MD USA Integrated Data Systems Department Siemens AG Corporate Research and Development Princeton NJ USA

We propose a unified framework based on a general definition of geometric transform (GeT) for modeling appearance. GeT represents the appearance by applying designed functionals over certain geometric sets. We show that image warping, Radon transform, trace transform, etc. are special cases of our definition. Moreover, three different types of GeTs are designed to handle deformation, articulation and occlusion and applied to fingerprinting the appearance inside a contour. They include the contour-driven GeT, the feature curve based GeT and selecting functionals to model the appearance inside the convex hull of the contour. A multi-resolution representation that combines both shape and appearance information is also proposed. We apply our approach to image synthesis and object recognition. The proposed approach produces promising results when applied to fingerprinting the appearance of human and body parts despite the challenges due to articulated motion and deformations

关键词： Solid modeling Context modeling Active appearance model Biological system modeling Shape Humans Fingerprint recognition Automation data systems Educational institutions

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Version management and historical queries in digital libraries

Version management and historical queries in digital librari...

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International Workshop on Temporal Representation and Reasoning (TIME)

作者： Fusheng Wang C. Zaniolo Xin Zhou H.J. Moon Integrated Data Systems Department Siemens AG Corporate Research and Development Princeton NJ USA Los Angeles Computer Science Department University of California Los Angeles CA USA

Historical information can be effectively preserved using XML and searched through powerful historical queries written in XQuery. Indeed, by storing the successive versions of a document in an incremental fashion, XML repositories and data warehouses can achieve (i) the efficient preservation of critical information, (ii) its representation using a temporally grouped data model and (iii) the ability of supporting historical queries on the evolution of documents and their contents using XQuery. The proposed approach can be applied uniformly to (a) XML document archives and (b) transaction time databases published in XML and queried in XQuery. Our case studies include the UCLA course catalog, W3C Xlink standards, and the CIA WorldFact Book, besides relational databases. The experience described here and in the work of Wang et al. (2005 and 2003) suggests that current standards provide reasonable support for temporal applications at the logical level, whereas many challenges remain at the physical level.

关键词： Software libraries XML History Relational databases data systems Educational institutions Moon Computer science data warehouses data models

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A coupled mode solution for acoustic propagation in a waveguide with stepwise depth variations

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The Journal of the Acoustical Society of America 2005年第S1期72卷 S59-S59页

作者： Richard B. Evans Ocean Data Systems Inc. 6000 Executive Boulevard Rockville MD 20852 Naval Ocean Research and Development Activity NSTL Station MS 39529

A coupled mode solution is formulated for the problem of acoustic propagation in a cylindrically symmetric ocean divided, in range, into a finite number of adjoining Pekeris waveguides of differing water depths. The problem is discretized by assigning a pressure release boundary condition at some large finite depth and including sufficient attenuation to exclude any significant energy returning to the water. This formulation includes backscatter from the depth variations of the waveguide and full cross coupling between a finite number of propagating and nonpropagating modes determined by the range and strength of the depth variations. Numerical results based on an implementation of this solution are presented. [Work supported by NORDA.]

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Climate reference network stations: Location, location, location...

Climate reference network stations: Location, location, loca...

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Combined Preprints: 84th American Meteorological Society (AMS) Annual Meeting

作者： Helfert, Michael R. Changery, Michael J. Easterling, David R. Janis, Michael J. Baker, Samuel M. Summer, Buford M. Graybeal, Daniel Y. Hubbard, Kenneth G. Redmond, Kelly T. May, Edwin L. NOAA National Climatic Data Center Asheville NC Southeast Regional Climate Center Department of Natural Resources Columbia SC Northeast Regional Climate Center Cornell University Ithaca NY High Plains Regional Climate Center University of Nebraska Lincoln NB Western Regional Climate Center Desert Research Institute Reno NV Short and Associates Inc. NOAA Office of Systems Development Washington DC Short and Associates Inc. NOAA Office of Systems Development Asheville NC National Climatic Data Center 151 Patton Avenue Asheville NC 28801

The United States Climate Reference Network (USCRN) goal is to document long-term climate behavior in accordance with the 1999 Climate Monitoring Principles certified by the National research Council. USCRN scientific success is based upon frontend careful and rigorous selection of appropriate instrument monitoring sites. The primary variables to be monitored are the air temperature and the precipitation. The secondary variables of solar radiation, wind velocity, and IR (skin) temperature are specificaily designed to support the precision and understanding of the primary instrument measurements. The Phase 1 plan is for about 100 USCRN stations to be deployed across the United States by the end of 2006. A secondary grid of 75 stations has been envisioned for Alaska, Hawaii, and perhaps Puerto Rico and the Virgin Islands. 49 USCRN stations are now operating. Two experimental stations are also operating in severe environments in Alaska. Criteria for USCRN sites targeted for operations during the next 50-100 years are very exacting. They exceed WMO standards for climate monitoring and station siting. This paper discusses primary climate station siting criteria: proper instrument and site exposures;land use and land tenure stability;avoidance of built-up areas and areas of future development;avoidance of agriculture, irrigated areas, and large artificial water bodies;regional climate representativiness with respect to temperature and precipitation;avoidance of localized microclimates, and consistent site maintenance and instrument recalibrations. Examples are given of sites and locations sensitive to climate change and of sites representing special circumstances and environments.

关键词： Weather information services

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Meanshift clustering for DNA microarray analysis

Meanshift clustering for DNA microarray analysis

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Proceedings of the IEEE Computational systems Bioinformatics Conference, CSB

作者： D. Barash D. Comaniciu Department of Computer Science Ben-Gurion University of the Negev Beersheba Israel Integrated Data Systems Department Siemens AG Corporate Research and Development Princeton NJ USA

Meanshift clustering is a well established algorithm that has been applied successfully in image processing and computer vision. Cluster centers are derived by local mode seeking identifying maxima in the normalized density of the data set. Recently, quantum clustering that highly resembles mean shift clustering has been proposed for analyzing microarray expression data. Quantum clustering is based on physical intuition derived from quantum mechanics. By an iterative process using a gradient descent procedure, the potential energy V belonging to the Hamiltonian of the time-independent Schrodinger equation develops minima that are identified with cluster centers. The analogies between the wavefunction in quantum clustering and the multivariate kernel density estimator in meanshift clustering are leading to closely related formulations. However, the approach towards the minima of the potential in quantum clustering needs to be performed unrelatedly to the formulation, by gradient descent steps. In contrast, in meanshift clustering the approach towards the maxima of the normalized density is performed by the meanshift vector that is derived by the formulation of the methodology. It points towards the direction of the maximum increase in the underlying density. Based on these observations, we propose implementing meanshift clustering to improve the efficiency of local mode seeking in analyzing expression data.

关键词： DNA data analysis Quantum mechanics Kernel Clustering methods Quantum computing Potential energy Computer science data systems Educational institutions

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Lossless data compression for infrared hyperspectral sounders - An overview

Lossless data compression for infrared hyperspectral sounder...

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Combined Preprints: 84th American Meteorological Society (AMS) Annual Meeting

作者： Huang, Bormin Huang, Hung-Lung Ahuja, Alok Chen, Hao Schmit, Timothy J. Heymann, Roger W. Coop. Inst. Meteorol. Satellite S. Space Science and Engineering Center University of Wisconsin-Madison Madison WI 53706 United States NOAA Natl. Environ. Satellite Data/I.S. Office of Research and Applications Madison WI 53706 United States Office of Systems Development Suitland MD 20746 United States CIMSS University of Wisconsin Madison

Hyperspectral sounding data requires accuracy for useful retrieval of atmospheric temperature, moisture, trace gases, clouds, aerosols and surface properties. Therefore, compression of hyperspectral sounding data is better to be lossless or near lossless. Given the large volume of three-dimensional hyperspectral data that will be generated by the hyperspectral sounders such as AIRS, CrIS, IASI, GIFTS and HES instruments, the use of robust data compression techniques will be beneficial to data transfer and archive. This paper reviews wavelet-based lossless data compression schemes for the 3D hyperspectral data using 3D integer wavelet transforms followed by 3D EZW and 3D SPIHT zerotree coding schemes. We extend both zerotree coding schemes to take on any size of satellite data, each of whose dimensions need not be divisible by 2N, where N is the layers of the wavelet decomposition being performed. The 2D wavelet-based JPEG-2000 compression scheme and some other prediction-based 2D lossless compression schemes such as CALIC and JPEG-LS are also investigated. Their compression ratios are presented.

关键词： Sounding apparatus

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A Review of Major Progresses in Mesoscale Dynamic research in China since 1999

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Advances in Atmospheric Sciences 2004年第3期21卷 497-504页

作者：周晓平陆汉城倪允琪谈哲敏 Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 Meteorological College PLA University of Science and Technology Nanjing 211101 Department of Atmospheric Sciences Nanjing University Nanjing 210093 Department of Atmospheric Sciences Nanjing University Nanjing 210093esoscale research conducted by Chinese meteorologists during the past four years is reviewed. Advances in theoretical studies include (a) mesoscale quasi-balanced and semi-balanced dynamics derived through scale analysis and the perturbation method which are suitable for describing mesoscale vortices (b) subcritical instability and vortex-sheet instability (c) frontal adjustment mechanism and the effect of topography on frontgenesis and (d) slantwise vorticity development theories the slantwise vortex equation and moist potential vorticity (MPV) anomalies with precipitation-related heat and mass sinks and MPV impermeability theorem. Prom the MPV conservation viewpoint the transformation mechanism between different scale weather systems is analyzed. Based on the data analysis a new dew-point front near the periphery of the West Pacific subtropical high is identified. In the light of MPV theory and Q-vector theory some events associated with torrential rain systems and severe storms are analyzed and diagnosed. Progress in mesoscale numerical simulation has been made in the development of meso-α meso-βvortices meso-γ-scale downbursts and precipitation produced by deep convective systems with MM5 and other mesoscale models.

Mesoscale research conducted by Chinese meteorologists during the past four years is reviewed. Advances in theoretical studies include (a) mesoscale quasi-balanced and semi-balanced dynamics, derived through scale analysis and the perturbation method which are suitable for describing mesoscale vortices; (b) subcritical instability and vortex-sheet instability; (c) frontal adjustment mechanism and the effect of topography on frontgenesis; and (d) slantwise vorticity development theories, the slantwise vortex equation, and moist potential vorticity (MPV) anomalies with precipitation-related heat and mass sinks and MPV impermeability theorem. Prom the MPV conservation viewpoint, the transformation mechanism between different scale weather systems is analyzed. Based on the data analysis, a new dew-point front near the periphery of the West Pacific subtropical high is identified. In the light of MPV theory and Q-vector theory, some events associated with torrential rain systems and severe storms are analyzed and diagnosed. Progress in mesoscale numerical simulation has been made in the development of meso-α, meso-β vortices, meso-γ-scale downbursts and precipitation produced by deep convective systems with MM5 and other mesoscale models.

关键词： mesoscale dynamics mesoscale numerical simulations observational data diagnoses

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Applying amorphous CoNbZr shield to improve the dielectric-breakdown voltages of the gap layers of narrow-gap read heads

Applying amorphous CoNbZr shield to improve the dielectric-b...

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International Conference on Magnetics (INTERMAG)

作者： K. Hoshino S. Odai M. Hatatani STR branch Office Central Research and Development Laboratory Hitachi Limited Kanagawa Japan Data Storage Systems Division Hitachi and Limited Kanagawa Japan

In this paper, the effect of the lower shield materials on the breakdown voltage of the lower insulating gap layer has been investigated. A hybrid shield CoNbZr layer on NiFe shield was applied ton the read , and the ... 详细信息

关键词： Amorphous materials Voltage Magnetic heads Dielectric measurements Electrodes Dielectrics and electrical insulation Dielectric substrates Testing Disk recording Hard disks

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Overview of the South China Sea Monsoon Experiment

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Advances in Atmospheric Sciences 2004年第3期21卷 343-360页

作者：丁一汇李崇银柳艳菊 National Climate Center China Meteorological Administration Beijing 100081 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 National Climate Center China Meteorological Administration Beijing 100081 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid DynamicsInstitute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029he present paper gives an overview of the key project " South China Sea Monsoon Experiment (SCSMEX)" operated by the Ministry of Science and Technology of China during the period of 1996-2001. The SCSMEX is a joint atmospheric and oceanic field experiment which aims to better understand the onset maintenance and variability of the summer monsoon over the South China Sea (SCS). It is a large-scale international effort with many participating countries and regions cooperatively involved in this experiment. With the field observation in May-August 1998 a large amount of meteorological and oceanic data was acquired which provides excellent datasets for the study of the SCS monsoon and the East Asian monsoon and their interaction with the ocean. The preliminary research achievements are as follows. (1) The earliest onset of the Asian monsoon over the SCS and Indo-China Peninsula has been well documented. Prom the viewpoint of the synoptic process its onset is closely related to the early rapid development of a twin cyclone to the east of Sri Lanka. The conceptual modei of the SCS monsoon onset in 1998 was put forward. The 50-year time series of the SCS monsoon onset date was also made. (2) Two major modes namely the 30-60-day and 10-20-day oscillations were ascertained. The influences of the abnormal SCS monsoon on the precipitation over eastern China and its modes were identifled. A strong (weak) monsoon over the SCS usually leads to less (more) precipitation over the middle and lower reaches of the Yangtze River

The present paper gives an overview of the key project ' South China Sea Monsoon Experiment (SCSMEX)' operated by the Ministry of Science and Technology of China during the period of 1996-2001. The SCSMEX is a joint atmospheric and oceanic field experiment which aims to better understand the onset, maintenance, and variability of the summer monsoon over the South China Sea (SCS). It is a large-scale international effort with many participating countries and regions cooperatively involved in this experiment. With the field observation in May-August 1998, a large amount of meteorological and oceanic data was acquired, which provides excellent datasets for the study of the SCS monsoon and the East Asian monsoon and their interaction with the ocean. The preliminary research achievements are as follows. (1) The earliest onset of the Asian monsoon over the SCS and Indo-China Peninsula has been well documented. Prom the viewpoint of the synoptic process, its onset is closely related to the early rapid development of a twin cyclone to the east of Sri Lanka. The conceptual modei of the SCS monsoon onset in 1998 was put forward. The 50-year time series of the SCS monsoon onset date was also made. (2) Two major modes, namely the 30-60-day and 10-20-day oscillations were ascertained. The influences of the abnormal SCS monsoon on the precipitation over eastern China and its modes were identifled. A strong (weak) monsoon over the SCS usually leads to less (more) precipitation over the middle and lower reaches of the Yangtze River basin, and more (less) precipitation in North China. (3) During the monsoon onset over the SCS, a wide variety of organized mesoscale convective systems (MCSs) were observed by a Doppler radar array deployed over the northern SCS. The relationship between large-scale circulations and MCSs during the monsoon onset process in 1998 was clearly revealed. It was suggested that there is a kind of positive feedback mechanism between large-scale circulations and

关键词： field experiment South China Sea monsoon low frequency oscillation (LFO) meso scale convective systems (MSCs) air-sea interaction numerical simulation

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