35440485
Some spectral techniques in coding theory
Abstract Let ⨍ be a real-valued function on the n -dimensional linear space F n over F ={0,1} and let A be a linear transformation of F n into F m . The Walsh spectrum of the composite ⨍ ∘ A is obtained. In particular, the Walsh spectrum of the degenerated function of ⨍ is obtained. Certain known related results are generalized.
11048111
Modified Chinese remainder theorem and its application to proxy signatures
Chinese Remainder Theorem has been used for hundreds of years and has been applied to many domains such as integers and polynomials. An assumption made is that the component moduli are pairwise co-prime. In this paper, first we remove this assumption; then we give an algorithm to find whether a given system of congruent equations has a solution, and if so, how to find the solution in an efficient manner. Further we apply the modified Chinese Remainder Theorem to design proxy signatures.
13639457
On the independence of Boolean functions
Boolean functions are widely used because they can be used to precisely describe logical circuits. Properties of Boolean functions with respect to their applications to cryptography have been studied, but relationship between Boolean functions are rarely studied. This paper studies the independence of Boolean functions, gives necessary and sufficient conditions for judging whether two given Boolean functions are independent. Some enumeration formulae are given.
414035
Internet voting: concerns and solutions
Internet voting systems, catering to different requirements, have been widely implemented and used. Some have been successful, while others have experienced unexpected problems. This paper overviews the concerns of using Internet voting and tries to give solutions. Tradeoffs between the advantages and disadvantages of employing Internet voting are also addressed. A simple protocol is designed to show that technical problems identified in the literature can be solved fairly easily, though some seem subtle. This study reveals that the main concerns of adopting Internet voting for critical elections are not cryptographic tools, but hardware and software reliability, and social and political issues. After discussing possible concerns about Internet voting and possible solutions or comments, we propose steps to enable Internet voting to be adopted even for critical elections.
41090415
Correlation immunity and resiliency of symmetric Boolean functions
Correlation immunity of symmetric Boolean functions is studied in this paper. Lower bounds on the number of constructible correlation immune symmetric functions are given. Constructions for such new balanced functions are presented. These functions are also known as 1-resilient functions. In 1985, Chor et al. conjectured that the only 1-resilient symmetric functions are the exclusive-or of all n variables and its negation. This conjecture, however, was disproved by Gopalakrishnan, Hoffman and Stinson in 1993 by giving a class of infinite counterexamples, and they noted that it does not seem to extend any further in an obvious way. In this paper two more infinite classes of such examples are presented for n being even and being odd, respectively, and consequently one of the two open problems proposed by Gopalakrishnan et al., is addressed by constructing new symmetric resilient functions.
47400657
Construction of correlation immune Boolean functions
It is shown in this paper that every correlation immune Boolean function of n variables can be written as f(x) = g(xGT ), where g is an algebraic non-degenerate Boolean function of k (k ≤ n) variables and G is a generating matrix of an [n, k, d] linear code. It is known that the correlation immunity of f (x) is at least d − 1. In this paper we further prove when the correlation immunity exceeds this lower bound. A method which can theoretically search exhaustively all possible correlation immune functions is proposed, while constructions of higher order correlation immune functions as well as algebraic non-degenerate correlation immune functions are discussed in particular. It is also shown that many cryptographic properties of g can be inherited by the correlation immune function f (x) = g(xGT) which is an important property for choosing useful correlation immune functions.
15142715
A cokriging method for estimating population density in urban areas
Population information is typically available for analysis in aggregate socioeconomic reporting zones, such as census blocks in the United States and enumeration districts in the United Kingdom. However, such data mask underlying individual population distributions and may be incompatible with other information sources (e.g. school districts, transportation analysis zones, metropolitan statistical areas, etc.). Moreover, it is well known that there are potential significance issues associated with scale and reporting units, the modifiable areal unit problem (MAUP), when such data are used in analysis. This may lead to biased results in spatial modeling approaches. In this study, impervious surface fraction derived from Thematic Mapper (TM) imagery was applied to derive the underlying population of an urban region. A cokriging method was developed to interpolate population density by modeling the spatial correlation and cross-correlation of population and impervious surface fraction. Results suggest that population density can be accurately estimated using cokriging applied to impervious surface fraction. In particular, the relative population estimation error is � 0.3% for the entire study area and 10–15% at block group and tract levels. Moreover, unlike other interpolation methods, cokriging gives estimation variance at the TM pixel level. 2005 Elsevier Ltd. All rights reserved.
40872599
Timestamp consistency and trace-driven analysis for distributed parallel systems
A continuous stream of event data describing the progress of parallel program execution is realized for trace-driven analysis. Unfortunately, it is often the case that separate streams are produced independently by multiple processors in the system, and the logical order of events cannot be guaranteed due to discrepancy among local clocks. We present an integrated approach for timestamp consistency and performance analysis techniques for IBM SPn systems. The trace facility requires no source code modification, and can generate message passing and system events with minimal trace overhead. Trace-driven analysis tools are developed to extract useful information. Analysis results for NAS kernel benchmarks are reported.<<ETX>>
26391037
Adaptive Checkpointing and Rollback in Multiprocessor Systems
12036966
Literature mining and database annotation of protein phosphorylation using a rule-based system
MOTIVATION
A large volume of experimental data on protein phosphorylation is buried in the fast-growing PubMed literature. While of great value, such information is limited in databases owing to the laborious process of literature-based curation. Computational literature mining holds promise to facilitate database curation.


RESULTS
A rule-based system, RLIMS-P (Rule-based LIterature Mining System for Protein Phosphorylation), was used to extract protein phosphorylation information from MEDLINE abstracts. An annotation-tagged literature corpus developed at PIR was used to evaluate the system for finding phosphorylation papers and extracting phosphorylation objects (kinases, substrates and sites) from abstracts. RLIMS-P achieved a precision and recall of 91.4 and 96.4% for paper retrieval, and of 97.9 and 88.0% for extraction of substrates and sites. Coupling the high recall for paper retrieval and high precision for information extraction, RLIMS-P facilitates literature mining and database annotation of protein phosphorylation.
5461786
Analysis and Comparison of Geometric and Algebraic Multigrid for Convection-Diffusion Equations
The discrete convection-diffusion equations obtained from streamline diffusion finite element discretization are solved on both uniform meshes and adaptive meshes. Estimates of error reduction rates for both geometric multigrid (GMG) and algebraic multigrid (AMG) are established on uniform rectangular meshes for a model problem. Our analysis shows that GMG with line Gauss-Seidel smoothing and bilinear interpolation converges if $h\gg \epsilon^{2/3}$, and AMG with the same smoother converges more rapidly than GMG if the interpolation constant $\beta$ in the approximation assumption of AMG satisfies $\beta \ll (\frac{h}{\sqrt{\epsilon}})^{\alpha}, \hs{1mm} \mbox{where $ \alpha = \Big\{ {\begin{smallmatrix} 1, & {h < \sqrt \varepsilon, } \\ 2, & {h \ge \sqrt \varepsilon.} \\ \end{smallmatrix}}$}$ On unstructured triangular meshes, the performance of GMG and AMG, both as solvers and as preconditioners for GMRES, are evaluated. Numerical results show that GMRES with AMG preconditioning is a robust and reliable solver on both type of meshes.