ppxscal/embedding_network huggingface dataset:
Even and odd holes in cap-free graphs
Authors: Michele Conforti, Gérard Cornuéjols, Ajai Kapoor, Kristina Vušković
Venue: Journal of Graph Theory (1999)

It is an old problem in graph theory to test whether a graph contains a chordless cycle of length greater than three (hole) with a specific parity (even, odd). Studying the structure of graphs without odd holes has obvious implications for Berge's strong perfect graph conjecture that states that a graph G is perfect if and only if neither G nor its complement contain an odd hole. Markossian, Gasparian, and Reed have proven that if neither G nor its complement contain an even hole, then G is &beta;-perfect. In this article, we extend the problem of testing whether G(V, E) contains a hole of a given parity to the case where each edge of G has a label odd or even. A subset of E is odd (resp. even) if it contains an odd (resp. even) number of odd edges. Graphs for which there exists a signing (i.e., a partition of E into odd and even edges) that makes every triangle odd and every hole even are called even-signable. Graphs that can be signed so that every triangle is odd and every triangle is odd and every hole is odd are called odd-signable. We derive from a theorem due to Truemper co-NP characterizations of even-signable and odd-signable graphs. A graph is strongly even-signable if it can be signed so that every cycle of length &ge; 4 with at most one chord is even and every triangle is odd. Clearly a strongly even-signable graph is even-signable as well. Graphs that can be signed so that cycles of length four with one chord are even and all other cycles with at most one chord are odd are called strongly odd-signable. Every strongly odd-signable graph is odd-signable. We give co-NP characterizations for both strongly even-signable and strongly odd-signable graphs. A cap is a hole together with a node, which is adjacent to exactly two adjacent nodes on the hole. We derive a decomposition theorem for graphs that contain no cap as induced subgraph (cap-free graphs). Our theorem is analogous to the decomposition theorem of Burlet and Fonlupt for Meyniel graphs, a well-studied subclass of cap-free graphs. If a graph is strongly even-signable or strongly odd-signable, then it is cap-free. In fact, strongly even-signable graphs are those cap-free graphs that are even-signable. From our decomposition theorem, we derive decomposition results for strongly odd-signable and strongly even-signable graphs. These results lead to polynomial recognition algorithms for testing whether a graph belongs to one of these classes. &copy; 1999 John Wiley & Sons, Inc. J Graph Theory 30: 289&ndash;308, 1999
Improving classification performance of sonar targets by applying general regression neural network with PCA
Authors: Burcu Erkmen, Tülay Yıldırım
Venue: Expert Systems with Applications: An International Journal (2008)

The remote detection of undersea mines in shallow waters using active sonar is a crucial subject required to maintain the security of important harbors and cost line areas. The discrimination sonar returns from mines and returns from rocks on the sea floor by human experts is usually difficult and very heavy workload. Neural network classifiers have been widely used in classification of complex sonar signals due to its adaptive and parallel processing ability. In this paper, due to the advantages on fast learning and convergence to the optimal regression surface as the number of samples becomes very large, general regression neural network (GRNN) has been used to solve the problem of classification underwater targets. Principal component analysis (PCA) has been established as a feature extraction method to improve classification performance. Receiver operating characteristic (ROC) analysis has been applied to the neural classifier to evaluate the sensitivity and specificity of diagnostic procedures.
Comparing negative binomial and recursive partitioning models for fault prediction
Authors: Elaine J. Weyuker, Thomas J. Ostrand, Robert M. Bell
Venue: Proceedings of the 4th international workshop on Predictor models in software engineering (2008)

Two different software fault prediction models have been used to predict the N% of the files of a large software system that are likely to contain the largest numbers of faults. We used the same predictor variables in a negative binomial regression model and a recursive partitioning model, and compared their effectiveness on three large industrial software systems. The negative binomial model identified files that contain 76 to 93 percent of the faults, and recursive partitioning identified files that contain 68 to 85 percent.
Effect of carrier frequency offset and phase noise on WFMT systems
Authors: Roman M. Vitenberg
Venue: Proceedings of the 6th WSEAS International Conference on Signal, Speech and Image Processing (2006)

This paper presents an analysis of the effect of the carrier frequency offset and phase noise on a performance of Wavelet based Filtered Multi-Tone (WFMT) systems for a general AWGN channel. It is well known that the carrier frequency offset in OFDM System yields to significant degradation of the signal-to-noise ratio (SNR). Below I show that a novel WFMT modulation is less sensitive to the frequency offset and phase noise in communication channel than OFDM /DMT modulation. The simple expression for SNR degradation in WFMT Systems is developed on base of preceding papers, those examine the carrier frequency offset effect on OFDM performance. The better performance of WFMT system versus OFDM is illustrated by calculation of SNR degradation in OFDM and WFMT systems with the same bandwidth and number of FFT points.
Counting rational points on curves over finite fields
Authors: Ming-Deh Huang, D. Ierardi
Venue: Proceedings of the 1993 IEEE 34th Annual Foundations of Computer Science (1993)

We consider the problem of counting the number of points on a plane curve, given by a homogeneous polynomial F/spl isin/F/sub p/[x, y, z], which is rational over the ground field F/sub p/. More precisely, we show that if we are given a projective plane curve C of degree n, and if C has only ordinary multiple points, then one can compute the number of F/sub p/-rational points on C in randomized time (log p)/sup /spl Delta// where /spl Delta/=(degF)/sup O(1/). The complexity of this construction improves previously known bounds for this problem by at least an order of magnitude.
The policy continuum-Policy authoring and conflict analysis
Authors: Steven Davy, Brendan Jennings, John Strassner
Venue: Computer Communications (2008)

The policy continuum is a fundamental component of any policy-based management implementation for autonomic networking, but as of yet has no formal operational semantics. We propose a policy continuum model and accompanying policy authoring process that demonstrates the key properties that set a continuum apart from a non-hierarchical policy model. As part of the policy authoring process we present a policy conflict analysis algorithm that leverages the information model, making it applicable to arbitrary applications and continuum levels. The approach for policy conflict analysis entails analysing a candidate policy (either newly created or modified) on a pair-wise basis with already deployed policies and potential conflicts between the policies are fed back to the policy author. Central to the approach is a two-phase algorithm which firstly determines the relationships between the pair of policies and secondly applies an application specific conflict pattern to determine if the policies should be flagged as potentially conflicting. In this paper we present the formal policy continuum and two-phase conflict analysis algorithm as part of the policy authoring process, we describe an implementation where we demonstrate the detection of potential conflicts within a policy continuum.
A New Alignment Algorithm to Identify Definitions Corresponding to Abbreviations in Biomedical Text
Authors: Yun Xu, ZhiHao Wang, YuZhong Zhao, Yu Xue
Venue: Proceedings of the First International Workshop on Knowledge Discovery and Data Mining (2008)

The exploding growth of the biomedical literature presents many challenges for biological researchers. One such challenge is from the use of a great deal of abbreviations. Extracting abbreviations and their definitions accurately is very helpful to biologists and also facilitates biomedical text analysis. Among existing approaches, text alignment algorithms are simple, effective and require no training data. However, state of the art alignment algorithms could not identify the definitions of irregular abbreviations (e.g., ). We propose an algorithm analogous to pairwise sequence alignment, in which it is given a penalty score if there are two unmatched characters separately from the abbreviation and definition, and in this way some irregular abbreviations are found.
Tight competitive ratios for parallel disk prefetching and caching
Authors: Wing-Kai Hon, Rahul Shah, Peter J. Varman, Jeffrey Scott Vitter
Venue: Proceedings of the twentieth annual symposium on Parallelism in algorithms and architectures (2008)

We consider the natural extension of the well-known single disk caching problem to the parallel disk I/O model (PDM) [17]. The main challenge is to achieve as much parallelism as possible and avoid I/O bottlenecks. We are given a fast memory (cache) of size M memory blocks along with a request sequence Σ =(b1,b2,...,bn) where each block bi resides on one of D disks. In each parallel I/O step, at most one block from each disk can be fetched. The task is to serve Σ in the minimum number of parallel I/Os. Thus, each I/O is analogous to a page fault. The difference here is that during each page fault, up to D blocks can be brought into memory, as long as all of the new blocks entering the memory reside on different disks. The problem has a long history [18, 12, 13, 26]. Note that this problem is non-trivial even if all requests in Σ are unique. This restricted version is called read-once. Despite the progress in the offline version [13, 15] and read-once version [12], the general online problem still remained open. Here, we provide comprehensive results with a full general solution for the problem with asymptotically tight competitive ratios. To exploit parallelism, any parallel disk algorithm needs a certain amount of lookahead into future requests. To provide effective caching, an online algorithm must achieve o(D) competitive ratio. We show a lower bound that states, for lookahead L ≤ M, any online algorithm must be Ω(D)-competitive. For lookahead L greater than M(1+1/ε), where ε is a constant, the tight upper bound of O(√MD/L) on competitive ratio is achieved by our algorithm SKEW. The previous algorithm tLRU [26] was O((MD/L)2/3)-competitive and this was also shown to be tight [26] for an LRU-based strategy. We achieve the tight ratio using a fairly different strategy than LRU. We also show tight results for randomized algorithms against oblivious adversary and give an algorithm achieving better bounds in the resource augmentation model.
The MooDS protocol: a J2ME object-oriented communication protocol
Authors: Romain Pellerin
Venue: Proceedings of the 4th international conference on mobile technology, applications, and systems and the 1st international symposium on Computer human interaction in mobile technology (2007)

This paper describes MooDS, an object-oriented communication protocol dedicated to Java 2 Micro Edition (J2ME) based mobile phones. This protocol is used in GASP, an open source middleware enabling J2ME multiplayer gaming interactions. This paper enlightens the difficulty in developing mutiplayer games in heavily constrained environments, like the J2ME CLDC platform: small application memory footprint, lack of object serialization support, network protocol limitations, small bandwith and lack of client IP addressing support within cellular phone networks. This paper details how MooDS takes care of these constraints by providing an efficient object serialization protocol in order to reduce the amount of transmitted data and to increase the communication speed. Moreover, MooDS is compared with the available J2ME SOAP based protocol implementations, kSOAP2 and JSR172. This paper shows that MooDS obtains the best results in terms of encoding length, transmission delay, memory allocation and application code size, thus supplying a proper gaming interaction support, in particular for time critical multiplayer games.
Iterated clique graphs with increasing diameters
Authors: Claudson F. Bornstein_aff1n2, Jayme L. Szwarcfiter
Venue: Journal of Graph Theory (1998)

A simple argument by Hedman shows that the diameter of a clique graph G differs by at most one from that of K(G), its clique graph. Hedman described examples of a graph G such that diam(K(G)) = diam(G) + 1 and asked in general about the existence of graphs such that diam(Ki(G)) = diam(G) + i. Examples satisfying this equality for i = 2 have been described by Peyrat, Rall, and Slater and independently by Balakrishnan and Paulraja. The authors of the former work also solved the case i = 3 and i = 4 and conjectured that such graphs exist for every positive integer i. The cases i &ge; 5 remained open. In the present article, we prove their conjecture. For each positive integer i, we describe a family of graphs G such that diam(Ki(G)) = diam(G) + i. &copy; 1998 John Wiley & Sons, Inc. J. Graph Theory 28: 147&ndash;154, 1998
Enhancing the Security Promise of a Digital Time-Stamp
Authors: Pei-yih Ting, Fang-dar Chu
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications (2008)

In this paper we present a trusted time-stamping service which issues time-stamps with enhanced security by a practical forward-secure proxy signature mechanism. This signature scheme provides a way to verify the validity of the delegation from the trusted time source through the common PKI certification hierarchy. The forward-security of this signature scheme provides better protection against key-exposure attack when time-stamping server gets intruded. The design of this signature scheme is tied closely to the time-stamping service based on hierarchicaldistributed time sources. The signature scheme is implemented with standard RSA signature and verification algorithms. The computation of signing and verification in providing the forward-security feature is absorbed into the proxy scheme. Only delegation and key-updating require minor extra computation. In addition, one safety assumption made implicitly in Krawczyk's forward-secure signature scheme is identified and eliminated such that the security of our scheme outperforms its predecessor.
Modeling viral economies for digital media
Authors: Shan He, Renan G. Cattelan, Darko Kirovski
Venue: Proceedings of the 3rd ACM SIGOPS/EuroSys European Conference on Computer Systems 2008 (2008)

Financial efficiency is the premier performance measure for most systems. Existing economic ecosystems for distribution of multimedia leave a lot to be desired: client-server platforms do not scale well resulting in substantial operational costs, whereas peer-to-peer platforms cannot police copyright control and are thus notorious for not being able to capitalize on its vast delivery potential. In this paper, we introduce an economic model that aims at predicting financial performance of both client-server and viral distribution systems for multimedia. The model consists of several probabilistic components: a global scale-free viral network of users and a localized user-behavior model that abstracts marketing, pricing, and executed transactions. The model uses simulation to predict relative economic behavior. In order to showcase our model, we compared the popular "on-line store" distribution system to the recently proposed off-line incentive-based viral ecosystem for multimedia. We also constructed an efficient dynamic pricing scheme and evaluated its performance in considered multimedia distribution scenarios.
Evaluation of the residual packet-loss rate using packet-level FEC for delay-constrained media network transport
Authors: Xunqi Yu, James W. Modestino, Dian Fan
Venue: Proceedings of the 2nd international conference on Mobile multimedia communications (2006)

We propose a system model and an evaluation methodology to describe the performance of general delay-constrained packet-media transport over networks protected by packet-level FEC. Furthermore, we describe an algorithm to compute the residual packet-loss rate after FEC decoding in delay-constrained packet-media transmissions. Finally, we illustrate the influence of several key system parameters on the performance of FEC through specific examples.
Lagrange multipliers and maximum information leakage in different observational models
Authors: Pasquale Malacaria, Han Chen
Venue: Proceedings of the third ACM SIGPLAN workshop on Programming languages and analysis for security (2008)

This paper explores two fundamental issues in Language based security. The first is to provide a quantitative definition of information leakage valid in several attacker's models. We consider attackers with different capabilities; the strongest one is able to observe the value of the low variables at each step during the execution of a program; the weakest one can only observe a single low value at some stage of the execution. We will provide a uniform definition of leakage, based on Information Theory, that will allow us to formalize and prove some intuitive relationships between the amount leaked by the same program in different models. The second issue is Channel Capacity, which in security terms amounts to answering the questions: given a program and an observational model, what is the maximum amount that the program can leak? And which input distribution causes the maximum leakage? To answer those questions we will introduce techniques from constrained non-linear optimization, mainly Lagrange multipliers and we will show how they provide a workable solution in all observational models considered. In the simplest setting, i.e. under minimal constraints, we will show that channel capacity is achieved by any input distribution which induces a uniform distribution on the observables.
Encoding process algebraic descriptions of web services into BPEL
Authors: Antonella Chirichiello, Gwen Salaün
Venue: Web Intelligence and Agent Systems (2007)

Formal methods are helpful for many issues raised in the web services area. In this article, we advocate the use of process algebra as a first step in the design and development of executable web services. Verification tools can be used to validate the correct execution of these formal descriptions. We define some guidelines to encode abstract specifications of services-to-be written using these calculi into executable web services. As a back-end language, we consider BPEL as the orchestration language. We illustrate our approach through the development of a simple e-business application.
Routing performance analysis of human-driven delay tolerant networks using the truncated levy walk model
Authors: Seongik Hong, Injong Rhee, Seong Joon Kim, Kyunghan Lee, Song Chong
Venue: Proceeding of the 1st ACM SIGMOBILE workshop on Mobility models (2008)

The routing performance of delay tolerant networks (DTN) is highly correlated with the distribution of inter-contact times (ICT), the time period between two successive contacts of the same two mobile nodes. As humans are often carriers of mobile communication devices, studying the patterns of human mobility is an essential tool to understand the performance of DTN protocols. From measurement studies of human contact behaviors, we find that their distributions closely resemble a form of power-law distributions called truncated Pareto. Human walk traces has a dichotomy distribution pattern of ICT; it has a power-law tendency up to some time, and decays exponentially after that time. Truncated Pareto distributions offer a simple yet cohesive mathematical model to express this dichotomy in the measured data. Using the residual and relaxation time theory [17] [4], we apply truncated Pareto distributions to quantify the performance of opportunistic routing in DTN. We further show that Truncated Levy walk (TLW) mobility model [22] commonly used in biology to describe the foraging patterns of animals [25], provide the same truncated power-law ICT distributions as observed from the empirical data, especially when mobility is confined within a finite area. This result confirms our recent finding that human walks contain similar statistical characteristics as Levy walks [22].
Improving word-recognizers using an interactive lexicon with active and passive words
Authors: Per Ola Kristensson, Shumin Zhai
Venue: Proceedings of the 13th international conference on Intelligent user interfaces (2008)

The words a user is likely to write comprise the user's active vocabulary. This vocabulary is considerably smaller than the passive vocabulary of words a user reads. We explore an interactive adaptive lexicon method that separates a large lexicon into active and passive sets, and gradually expands and adapts the active set to reflect the user's active vocabulary. The adaptation is achieved through lightweight interaction as a by product of actual use. The effectiveness of the technique is demonstrated through a computational experiment and a user study.
Analysis of dynamic power management on multi-core processors
Authors: W. Lloyd Bircher, Lizy K. John
Venue: Proceedings of the 22nd annual international conference on Supercomputing (2008)

Power management of multi-core processors is extremely important because it allows power/energy savings when all cores are not used. OS directed power management according to ACPI (Advanced Power and Configurations Interface) specifications is the common approach that industry has adopted for this purpose. While operating systems are capable of such power management, heuristics for effectively managing the power are still evolving. The granularity at which the cores are slowed down/turned off should be designed considering the phase behavior of the workloads. Using 3-D, video creation, office and e-learning applications from the SYSmark benchmark suite, we study the challenges in power management of a multi-core processor such as the AMD Quad-Core Opteron" and Phenom". We unveil effects of the idle core frequency on the performance and power of the active cores. We adjust the idle core frequency to have the least detrimental effect on the active core performance. We present optimized hardware and operating system configurations that reduce average active power by 30% while reducing performance by an average of less than 3%. We also present complete system measurements and power breakdown between the various systems components using the SYSmark and SPEC CPU workloads. It is observed that the processor core and the disk consume the most power, with core having the highest variability.
Analyzing Multivariate Calibration Techniques for Glucose Level Prediction in Non-invasive Human Tongue Spectra
Authors: S. R. Naqvi, M. Saeed, N. Azeemi
Venue: Proceedings of the 2008 International Conference on Biocomputation, Bioinformatics, and Biomedical Technologies (2008)

Non-Invasive Glucose Monitoring devices use Multivariate Calibration (MC) methods to estimate glucose concentration in blood. The accuracy of methods depends on spectral data obtained from tongue-to-spectrometer interface. In this work we examine four widely used MC methods, they are: Classical Least Square (CLS), Inverse Least Square (ILS), Principal Component (PC) and Partial Least Square (PLS). We discuss the impact of factor selection on the prediction of response for first overtone transmission spectra collected across human tongues. Results are exposed for various Signal-to-Noise Ratio (SNR) and different factor values. We explicitly tackle the issue of low SNR in tongue-to-spectrometer interface. We show that CLS outperforms factor based regression techniques where SNR is as low as 30 dB. Our results are useful in calibration models that are used to predict vivo glycemia from human tongue spectra.