Inpainting of binary images using the Cahn-Hilliard equation.

Image inpainting is the filling in of missing or damaged regions of images using information from surrounding areas. We outline here the use of a model for binary inpainting based on the Cahn-Hilliard equation, which allows for fast, efficient inpainting of degraded text, as well as super-resolution of high contrast images.     

A nonparametric statistical method for image segmentation using information theory and curve evolution.

In this paper, we present a new information-theoretic approach to image segmentation. We cast the segmentation problem as the maximization of the mutual information between the region labels and the image pixel intensities, subject to a constraint on the total length of the region boundaries. We assume that the probability densities associated with the image pixel intensities within each region are completely unknown a priori, and we formulate the problem based on nonparametric density estimates. Due to the nonparametric structure, our method does not require the image regions to have a particular type of probability distribution and does not require the extraction and use of a particular statistic. We solve the information-theoretic optimization problem by deriving the associated gradient flows and applying curve evolution techniques. We use level-set methods to implement the resulting evolution. The experimental results based on both synthetic and real images demonstrate that the proposed technique can solve a variety of challenging image segmentation problems. Futhermore, our method, which does not require any training, performs as good as methods based on training.     

Calculation of the electric field enhancement for a degenerate diffusion process

The internal electric field produced by a constant source impurity diffusion is calculated using Fermi-Dirac statistics for the majority carrier. Numerical results indicate that treating the material as if it were nondegenerate always produces an underestimate in the electric field. The field enhancement factor which gives the ratio of the effective diffusion coefficient to the impurity diffusion coefficient valid for a degenerate diffusion process is clarified.     

Thermal denaturation of soy proteins as related to their dye-binding characteristics and functionality

The binding of Cresol Red and of Acid Orange 10 (in the absence and presence of urea) to unheated and progressively heated, defatted soy meal was compared with their NSI values, urease activities,in vitro digestibilities, unreactive lysine contents, and foaming and emulsifying capacities. These results suggested that increased amounts of Cresol Red and of Acid Orange 10 (in the presence of urea) bound to the heated samples were due to the progressive exposure of hydrophobic residues caused thermal denaturation. High statistical correlations were obtained between dye-binding, the duration of heating, and functional properties. Our results indicate that dye-binding has potential for predicting certain functional properties as well as for monitoring thermal denaturation of soy proteins.     

Construction of validated, non-redundant composite protein sequence databases

A strategy has been developed for the construction of a validated,comprehensive composite protein sequence database. Entries areamalgamated from primary source data bases by a largely automatedset of processes in which redundant and trivially differententries are eliminated. A modular approach has been adoptedto allow scientific judgement to be used at each stage of databaseprocessing and amalgamation. Source databases are assigned apriority depending on the quality of sequence validation andcommenting. Rejection of entries from the lower priority database,in each pairwise comparison of databases, is carried out accordingto optionally defined redundancy criteria based on sequencesegment mismatches. Efficient algorithms for this methodologyare embodied in the COMPO software system. COMPO has been appliedfor over 2 years in construction and regular updating of theOWL composite protein sequence database from the source databasesNBRF-PIR, SWISS-PROT, a GenBank translation retrieved from thefeature tables, NBRF-NEW, NEWAT86, PSD-KYOTO and the sequencescontained in the Brookhaven protein structure databank. OWLis part of the ISIS integrated data resource of protein sequenceand structure [Akrigg et al. (1988) Nature, 335, 745–746].The modular nature of the integration process greatly facilitatesthe frequent updating of OWL following releases of the sourcedatabases. The extent of redundancy in these sources is revealedby the comparison process. The advantages of a robust compositedatabase for sequence similarity searching and information retrievalare discussed.     

Structural Studies of Anomalous Behavior in the Silica-Alumina Gel System

This paper compares the structure ofAl₂O₃-SiO₂ xerogels prepared with Al₂O₃ contents ranging from 21 to 75 wt% (13 to 64 mol%). The 47 wt% Al₂O₃ xerogel (Al/Si ≅ 1) exhibits anomalously low surface area (≅1 m²/g) and skeletal density compared with other Al₂O₃-Si₂ compositions. Based on the results of nitrogen adsorption/condensation, helium displacement, high-resolution transmission electron microscopy (HRTEM), small-angle X-ray scattering (SAXS), and small-angle neutron scattering (SANS), we attribute the low surface area and skeletal density (density of the solid phase which is inaccessable to helium) to the formation of closed micropores, whereas the higher surface area materials exhibit a slightly coarser texture comprising open pores with radii of ≅1 nm. X-ray diffraction (XRD) and ²⁹SI and ²⁷Al magic-angle spinning nuclear magnetic resonance (MASNMR) indicate no anomalous behavior in the 47% sample on molecular length scales. HRTEM indicates the presence of a small fraction of crystallites which is supported by the SAXS results, but it is unknown if this crystallinity is related to low surface area. Low-field ¹H NMR spin-lattice relaxation measurements show that the physical structure of all of the 'wet' gels is similar implying that pore closure occurs during drying. Consistent with this idea, gel surface area and density increased significantly when the pore fluid (water) was replaced with a lower surface tension fluid (formamide, dioxane, ethanol. water/surfactant).     

朗讯重新定义服务概念

朗讯科技（中国）公司借上海“2005年中国国际信息通信展览会”之机,于2005年6月21日在沪举办了“2005通信服务高层论坛-朗讯服务解决方案研讨会”,邀请国内政府机构、运营商以及企业代表与来自国际知名运营商和朗讯全球服务部（IWS）的专家们一道,共同探讨通信业务和通信服务面临的挑战、未来发展方向以及相关的服务解决方案。     

Accelerating Machine-Learning Algorithms on FPGAs using Pattern-Based Decomposition

Machine-learning algorithms are employed in a wide variety of applications to extract useful information from data sets, and many are known to suffer from super-linear increases in computational time with increasing data size and number of signals being processed (data dimension). Certain principal machine-learning algorithms are commonly found embedded in larger detection, estimation, or classification operations. Three such principal algorithms are the Parzen window-based, non-parametric estimation of Probability Density Functions (PDFs), K-means clustering and correlation. Because they form an integral part of numerous machine-learning applications, fast and efficient execution of these algorithms is extremely desirable. FPGA-based reconfigurable computing (RC) has been successfully used to accelerate computationally intensive problems in a wide variety of scientific domains to achieve speedup over traditional software implementations. However, this potential benefit is quite often not fully realized because creating efficient FPGA designs is generally carried out in a laborious, case-specific manner requiring a great amount of redundant time and effort. In this paper, an approach using pattern-based decomposition for algorithm acceleration on FPGAs is proposed that offers significant increases in productivity via design reusability. Using this approach, we design, analyze, and implement a multi-dimensional PDF estimation algorithm using Gaussian kernels on FPGAs. First, the algorithm’s amenability to a hardware paradigm and expected speedups are predicted. After implementation, actual speedup and performance metrics are compared to the predictions, showing speedup on the order of 20× over a 3.2 GHz processor. Multi-core architectures are developed to further improve performance by scaling the design. Portability of the hardware design across multiple FPGA platforms is also analyzed. After implementing the PDF algorithm, the value of pattern-based decomposition to support reuse is demonstrated by rapid development of the K-means and correlation algorithms.     

Analysis of the Electromagnetic Signals of the Human Brain: Milestones, Obstacles, and Goals

Measuring the functioning of the human brain is one of the most formidable scientific/engineering endeavors ever undertaken. It is difficult to extract information about any particular processing function from brain electromagnetic signals (BEMS) since, at any instant, only a small fraction of the brain's hundreds of simultaneously active major systems might be performing processing related to the function being studied. With recent developments, a new era of research is dawning based on an interdisciplinary approach in which advanced signal processing methods are focused on increasingly more specific neuroanatomical, neurophysiological, and neuropsychological research questions and clinical applications. This brief review highlights the major accomplishments of the last several decades in human BEMS analysis and discusses obstacles to progress. Five main topics are addressed: 1) the historical problem of developing a computerized expert clinical electroencephalogram (EEG) system; 2) advances in signal processing methods, including primary analysis, feature extraction, and statistical hypothesis testing and pattern classification; 3) integrated computing systems for BEMS analysis; 4) biophysical, basic science, practical and conceptual obstacles to progress; and 5) the long-term goal of developing a device for measuring the functional integrity of major neural systems, and the related topic of neurocybernetics. Cutting-edge issues discussed include measurement and modeling of nonstationary event-related signals, characterization of spatial processes, single-trial signal detection, location of the sources of scalp-recorded field distributions, and studies of the functional significance of BEMS.     

Electrical impedance spectroscopy of the human prostate

Tissue electrical impedance is a function of its architecture and has been used to differentiate normal and cancer tissues in a variety of organs including breast, cervix, skin, and bladder. This paper investigates the possibility of differentiating normal and malignant prostate tissue using bioimpedance spectra. A probe was designed to measure impedance spectra over the range of 10 kHz to 1 MHz. The probe was fully characterized using discrete loads and saline solutions of different concentrations. Impedance spectra of five ex vivo prostates were measured in the operating room immediately following radical prostatectomy. Wilcoxon signed-rank tests were used to compare the normal and malignant findings. The impedance probe had a signal-to-noise ratio (SNR) > 84 dB across the entire spectrum and measured a tissue volume of approximately 46 mm(3). At 10 kHz, prostate conductivity (or) ranged from 0.232 S/m to 0.310 S/m for tumor and from 0.238 S/m to 0.901 S/m for normal tissue. At 1 MHz the ranges were 0.301 S/m to 0.488 S/m for tumor and 0.337 S/m to 1.149 S/m for normal. Prostate permittivity (epsilonr) ranged from 6.64 x10(4) to 1.25 x 10(5) for tumor and from 9.08 x 10(4) to 4.49 x 10(5) for normal tissues at 10 kHz. And, at 1 MHz the er ranges were 9.23 x 10(2) to 1.88 x 10(3) for tumor and 1.16 x 10(3) to 2.18 x 10(3) for normal tissue. Both sigma and epsilonr of tumor tissue were found to be significantly lower than that of normal tissue (P < 0.0001). Conductivity and permittivity are both higher in normal prostate tissues than they are in malignant tissue making them suitable parameters for tissue differentiation. This is in agreement with trends observed in other tissues reported in much of the literature. Expanded studies are needed to further validate this finding and to explore the biological mechanism responsible for generating the results.