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Dirty paper coding are relevant for wireless networks, multiuser channels, and digital watermarking. We show that the problem of dirty paper is essentially equivalent to some classes of constrained memories, and we explore the binary so-called nested codes, which are used for efficient coding and error-correction on such channels and memories. Keywords: dirty paper, constrained memory, nested codes, covering codes. [ABSTRACT FROM AUTHOR]

This paper is concerned with a multi-resolution tool for analysis of a time series aiming to detect abnormalities in various frequency regions. The task is treated as a kernel based novelty detection applied to a multi-level time series representation obtained from the discrete wavelet transform. Having a priori knowledge that the abnormalities manifest themselves in several frequency regions, a committee of detectors utilizing data dependent aggregation weights is build by combining outputs of detectors operating in those regions. [ABSTRACT FROM AUTHOR]

One of the simplest protocols for clock synchronization in wireless ad hoc and sensor networks is the converge-to-max protocol, which has the simple logic of adjusting each node's clock to be at least as large as any neighbor's. This paper examines the converge-to-max protocol, showing it to be stabilizing even when node clocks have skew, bounded domains, and dynamic communication links. [ABSTRACT FROM AUTHOR]

In this paper we extend the Least Squares Monte Carlo approach proposed by Longstaff and Schwartz for the valuation of American-style contingent-claims to the case of life insurance contracts. These contracts, in fact, often embed an American-style option, called surrender option, that entitles its owner to terminate early the contract and receive a cash amount, called surrender value. The additional complication arising in life insurance policies with respect to purely financial American contracts is that there is not a fixed date within which the option can be exercised, since its "maturity" is driven by mortality factors. This complication has been handled by very few papers, often at the cost of excessively simplified valuation frameworks. The aim of this contribution, that is not a specific valuation model but a methodological approach, is to allow a full exploitation of the flexibility inborn in Monte Carlo and quasi-Monte Carlo methods in order to deal with more realistic valuation frameworks. [ABSTRACT FROM AUTHOR]

Genetic programming has been used by Koza and many others to design electrical, mechanical, and mechatronic systems, including systems with both active and passive components. This work has often required large population sizes (on the order of ten thousand) and millions of design evaluations to allow evolution of both the topology and parameters of interesting systems. For several years, the authors have studied the evolution of multi-domain engineering systems represented as bond graphs, a form that provides a unified representation of mechanical, electrical, hydraulic, pneumatic, thermal, and other systems in a uni-fied representation. Using this approach, called the Genetic Programming/Bond Graph (GPBG) approach, they have tried to evolve systems with perhaps tens of components, but looking at only 100,000 or fewer design candidates. The GPBG system uses much smaller population sizes, but seeks to maintain diverse search by using "sustained" evolutionary search processes such as the Hierarchical Fair Competition principle and its derivatives. It uses stochastic setting of parameter values (resistances, capacitances, etc.) as a means of evolving more robust designs. However, in past work, the GPBG system was able to model and simulate only passive components and simple (voltage or current, in the case of electrical systems) sources, which severely restricted the domain of problems it could address. Thus, this paper reports the first steps in enhancing the system to include active components. To date, only three models of a transistor and one model of an operational amplifier (op amp) are analyzed and implemented as two-port bond graph components. The analysis method and design strategy can be easily extended to other models or other active components or even multi-port components. This chapter describes design of an active analog low-pass filter with fifth-order Bessel characteristics. A passive filter with the same characteristics is also evolved with GPBG. Then the best designs emerging from each of these two procedures are compared. [The runs reported here are intended only to document that the analysis tools are working, and to begin study of the effects of stochasticity, but not to determine the power of the design procedure. The initial runs did not use HFC or structure fitness sharing, which will be included as soon as possible. Suitable problems will be tackled, and results with suitable numbers of replicates to allow drawing of statistically valid conclusions will be reported in this paper, to determine whether interesting circuits can be evolved more efficiently in this framework than using other GP approaches.] [ABSTRACT FROM AUTHOR]

The Direct Anonymous Attestation (DAA) scheme provides a means for remotely authenticating a trusted platform whilst preserving the user's privacy. The protocol has been adopted by the Trusted Computing Group (TCG) in the latest version of its Trusted Platform Module (TPM) specification. In this paper we show DAA places an unnecessarily large burden on the TPM host. We demonstrate how corrupt administrators can exploit this weakness to violate privacy. The paper provides a fix for the vulnerability. Further privacy issues concerning linkability are identified and a framework for their resolution is developed. In addition an optimisation to reduce the number of messages exchanged is proposed. [ABSTRACT FROM AUTHOR]

In this paper, we present the Deployment Support Network (DSN), a new methodology for developing and testing wireless sensor networks (WSN) in a realistic environment. With an additional wireless backbone network a deployed WSN can be observed, controlled, and reprogrammed completely over the air. The DSN provides visibility and control in a similar way as existing emulation testbeds, but overcomes the limitations of wired infrastructures. As a result, development and experiments can be conducted with realistic in- and outdoor deployments. The paper describes the new concept and methodology. Additionally, an architecture-independent implementation of the toolkit is presented, which has been used in an industrial case-study. [ABSTRACT FROM AUTHOR]

The Shortest Common Supersequence Problem (SCSP) is a well-known hard combinatorial optimization problem that formalizes many real world problems. This paper presents a novel randomized search strategy, called probabilistic beam search (PBS), based on the hybridization between beam search and greedy constructive heuristics. PBS is competitive (and sometimes better than) previous state-of-the-art algorithms for solving the SCSP. The paper describes PBS and provides an experimental analysis (including comparisons with previous approaches) that demonstrate its usefulness. [ABSTRACT FROM AUTHOR]

In certain classes of chemical reaction networks (CRN), there may be two stable states. The challenge is to find a model of the CRN such that the stability properties can be predicted. In this paper we consider the problem of building a P-system designed to simulate the CRN in an attempt to determine if the CRN is stable or bistable. We found that for the networks in [2] none of the bistable CRN would have a bistable P-system by stoichiometry alone. The reaction kinetics must be included in the P-system model; the implementation of which has been considered an open problem. In this paper we conclude that a P-system for a CRN in m reactants and n products has at most 2(m2 + mn) membranes and 6(m2 + mn) rules. This suggests that P-system models of a chemical reaction network, including both stoichiometry and reaction kinetics can be built. [ABSTRACT FROM AUTHOR]

A comprehensive view of speech and voice technologies is now demanding better and more complex tools amenable of extracting as much knowledge about sound and speech as possible. Many knowledge-extraction tasks from speech and voice share well-known procedures at the algorithmic level under the point of view of bio-inspiration. The same resources employed to decode speech phones may be used in the characterization of the speaker (gender, age, speaking group, etc.). Based on these facts the present paper examines a hierarchy of sound processing levels at the auditory and perceptual levels on the brain neural paths which can be translated into a bio-inspired audio-processing architecture. Through this paper its fundamental characteristics are analyzed in relation with current tendencies in cognitive audio processing. Examples extracted from speech processing applications in the domain of acoustic-phonetics are presented. These may find applicability in speaker's characterization, forensics, and biometry, among others. [ABSTRACT FROM AUTHOR]

Spam is commonly defined as unsolicited email messages and the goal of spam filtering is to distinguish between spam and legitimate email messages. Much work has been done to filter spam from legitimate emails using machine learning algorithm and substantial performance has been achieved with some amount of false positive (FP) tradeoffs. In the case of spam detection FP problem is unacceptable sometimes. In this paper, an adaptive spam filtering model has been proposed based on Machine learning (ML) algorithms which will get better accuracy by reducing FP problems. This model consists of individual and combined filtering approach from existing well known ML algorithms. The proposed model considers both individual and collective output and analyzes them by an analyzer. A dynamic feature selection (DFS) technique also proposed in this paper for getting better accuracy. [ABSTRACT FROM AUTHOR]

Availability of computer resources is key factor limiting use of bioinformatics analyses as a result of the growing computational demands. Grid computing provides a way to meet these requirements. But it is complicated to build a grid for users. This paper describes an approach to solve this problem using Grid Service technologies. Building the grid based on accepted standards and platforms makes the development and deployment of the grid much easier. A bioinformatics grid computing environment (BioGrid) which consists of the distributed computing application for bioinformatics is presented in this paper. Based on this environment, we propose the architecture of bioinformatics applications which is delivered using Grid Services constructed with the Globus Toolkit 4. We developed a simple program which is defined as the client-server application with grid services. It provides users an approach of grid services to impose grid resources and customize their own grid applications. [ABSTRACT FROM AUTHOR]

Separated grid systems are becoming the new information islands when more and more grid systems are deployed. Grid interoperation is a direction to solve that problem. This paper introduces the implementation of data interoperation between ChinaGrid and SRB. The data interoperation between them is divided into two parts: data access from SRB to ChinaGrid and from ChinaGrid to SRB. Also this paper considers the issues about performance optimization. We get a satisfied experiment result through the optimization measures. [ABSTRACT FROM AUTHOR]

Scale space interest points capture important photometric and deep structure information of an image. The information content of such points can be made explicit using image reconstruction. In this paper we will consider the problem of combining multiple types of interest points used for image reconstruction. It is shown that ordering the complete set of points by differential (quadratic) TV-norm (which works for single feature types) does not yield optimal results for combined point sets. The paper presents a method to solve this problem using canonical sets of scale space features. Qualitative and quantitative analysis show improved performance over simple ordering of points using the TV-norm. [ABSTRACT FROM AUTHOR]

Yao's classical millionaires' problem is about securely determining whether x > y, given two input values x,y, which are held as private inputs by two parties, respectively. The output x > y becomes known to both parties. In this paper, we consider a variant of Yao's problem in which the inputs x,y as well as the output bit x > y are encrypted. Referring to the framework of secure n-party computation based on threshold homomorphic cryptosystems as put forth by Cramer, Damgård, and Nielsen at Eurocrypt 2001, we develop solutions for integer comparison, which take as input two lists of encrypted bits representing x and y, respectively, and produce an encrypted bit indicating whether x > y as output. Secure integer comparison is an important building block for applications such as secure auctions. In this paper, our focus is on the two-party case, although most of our results extend to the multi-party case. We propose new logarithmic-round and constant-round protocols for this setting, which achieve simultaneously very low communication and computational complexities. We analyze the protocols in detail and show that our solutions compare favorably to other known solutions. [ABSTRACT FROM AUTHOR]

Multivariate Cryptography has been an active line of research for almost twenty years. While most multivariate cryptosystems have been under attack, variations of the basic schemes came up as potential repairs. In this paper, we study the Internal Perturbation variation of HFE recently proposed by Ding and Schmidt. Although several results indicate that HFE is vulnerable against algebraic attacks for moderate size parameters, Ding and Schmidt claim that the cryptosystem with internal perturbation should be immune against them. However in this paper, we apply the recently discovered method of differential analysis to the Internal Perturbation of HFE and we find a subtle property which allows to disclose the kernel of the perturbation. Once this has been achieved, the public key can be inverted by attacking the underlying HFE provided the parameters were taken low enough to make the perturbed scheme of competitive performance. [ABSTRACT FROM AUTHOR]

This paper reviews the recent use of genetic programming to automatically synthesize human-competitive designs of complex structures in six engineering domains, namely analog electrical circuits, optical lens systems, controllers, antennas, mechanical systems, and quantum computing circuits. First, the paper identifies common features observed in the human-competitive results produced by genetic programming in the six domains and suggests possible explanations for the observed similarities. Second, the paper identifies the characteristics that make a particular domain amenable to the application of genetic programming for the automatic synthesis of designs. Third, the paper discusses certain domain-specific adjustments in technique that may increase the efficiency of the automated process in a particular domain. Fourth, the paper discusses several technique issues that have arisen in more than one domain. [ABSTRACT FROM AUTHOR]

We consider an extensional version, called qmTT, of the intensional Minimal Type Theory mTT, introduced in a previous paper with G. Sambin, enriched with proof-irrelevance of propositions and effective quotient sets. Then, by using the construction of total setoid à la Bishop we build a model of qmTT over mTT. The design of an extensional type theory with quotients and its interpretation in mTT is a key technical step in order to build a two level system to serve as a minimal foundation for constructive mathematics as advocated in the mentioned paper about mTT. [ABSTRACT FROM AUTHOR]

This paper gives a broad overview of the area of searching with errors and the related field of error-correcting coding. In the vast literature regarding this problem, many papers simultaneously deal with various sorts of restrictions on the searching protocol. We partition this survey into sections, choosing the most appropriate section for each topic. [ABSTRACT FROM AUTHOR]

This paper studies a gathering problem for a system of asynchronous autonomous mobile robots that can move freely in a two-dimensional plane. We consider robots equipped with inaccurate (incorrect) compasses which may point a different direction from other robots' compasses. A gathering problem is that the robots are required to eventually gather at a single point which is not given in advance from any initial configuration. In this paper, we propose several inaccurate compass models and give two algorithms which solve the gathering problem on these models. One algorithm is the first result dealing with the compasses whose indicated direction may change in every beginning of execution cycles of robots. It solves the problem when compasses point different at most π/8 from the (absolute) north. The other one solves the problem when the compasses never change its pointed direction and their difference is at most π/3 among robots. [ABSTRACT FROM AUTHOR]