ppxscal/embedding_network huggingface dataset:
Shape recovery from turntable sequence using rim reconstruction
Authors: H. Zhong, W. S. Lau, W. F. Sze, Y. S. Hung
Venue: Pattern Recognition (2008)

This paper makes use of both feature points and silhouettes to deliver fast 3D shape recovery. The algorithm exploits object silhouettes in two views to establish a 3D rim curve, which is defined with respect to the two frontier points arising from two views. The images of this 3D rim curve in the two views are matched using cross-correlation technique. A 3D planar rim curve is then reconstructed using point-based reconstruction method. A set of 3D rim curves enclosing the object can be obtained from an image sequence captured under circular motion. Silhouettes are further utilized to check for mismatched rim points. The proposed method solves the problem of reconstruction of concave object surface, which is usually left unresolved in general silhouette-based reconstruction methods. In addition, the property of the reconstructed 3D rim curves allows fast surface extraction. Experimental results with real data are presented.
Differentials-based segmentation and parameterization for point-sampled surfaces
Authors: Yong-Wei Miao, Jie-Qing Feng, Chun-Xia Xiao, Qun-Sheng Peng, A. R. Forrest
Venue: Journal of Computer Science and Technology (2007)

Efficient parameterization of point-sampled surfaces is a fundamental problem in the field of digital geometry processing. In order to parameterize a given point-sampled surface for minimal distance distortion, a differentials-based segmentation and parameterization approach is proposed in this paper. Our approach partitions the point-sampled geometry based on two criteria: variation of Euclidean distance between sample points, and angular difference between surface differential directions. According to the analysis of normal curvatures for some specified directions, a new projection approach is adopted to estimate the local surface differentials. Then a k-means clustering (k-MC) algorithm is used for partitioning the model into a set of charts based on the estimated local surface attributes. Finally, each chart is parameterized with a statistical method -- multidimensional scaling (MDS) approach, and the parameterization results of all charts form an atlas for compact storage.
Computerized Segmentation and Classification of Breast Lesions Using Perfusion Volume Fractions in Dynamic Contrast-enhanced MRI
Authors: Sang Ho Lee, Jong Hyo Kim, Jeong Seon Park, Jung Min Chang, Sang Joon Park, Yun Sub Jung, Woo Kyung Moon
Venue: Proceedings of the 2008 International Conference on BioMedical Engineering and Informatics - Volume 02 (2008)

This study is designed to segment suspiciousregions using automatic computerized procedures andto classify kinetic patterns using commerciallyavailable three-time-points (3TP) method of computeraideddiagnosis. A novel evaluation method usingperfusion volume fractions is introduced for examiningmeaningful kinetic features in differentiation of benignand malignant breast lesions. Dynamic contrastenhancedMRI was applied to 24 lesions (12 malignant,12 benign). Thresholding for suspicious regions,region growing segmentation, hole-filling and 3Dmorphological erosion and dilation were performedfor extracting final lesion volume. The lesion sphericityand center distance of mass to surface area ratio(CDMSAR) were considered in the process ofautomatic segmentation. The kinetic patterns for eachlesion were classified into six classes by the 3TPmethod. Perfusion volume fraction for each class wascalculated in three partitions of whole, rim and corevolumes of a lesion. Receiver operating characteristiccurve (ROC) analysis was performed using theperfusion volume fractions. When using perfusionvolume fractions divided into rim and core lesionvolume, the classes having more improved accuracyappeared than using perfusion volume fractions withinwhole lesion volume. This result indicates that lesionclassification using local perfusion volume fractions ishelpful in selecting meaningful kinetic patterns fordifferentiation of benign and malignant lesions.
Visualizing decision process on spheres based on the even swap concept
Authors: Han-Lin Li, Li-Ching Ma
Venue: Decision Support Systems (2008)

The Even Swap method, originally outlined by Benjamin Franklin 230 years ago, is a rational way of finding the best alternative by evenly swapping decision criteria. This study develops a Decision Ball model to assist a decision maker in ranking alternatives and visualizing decision process based on the Even Swap concept. By viewing the moving trajectories of alternatives on spheres, a decision maker can specify trade-offs among criteria via the Even Swap process thus ranking alternatives more consistently.
Looking at the Class Associative Classification Training Algorithm
Authors: Fadi Thabtah, Qazafi Mahmood, Lee McCluskey
Venue: Proceedings of the Fifth International Conference on Information Technology: New Generations (2008)

Associative classification (AC) is a branch in data mining that utilises association rule discovery methods in classification problems. In this paper, we propose a new training method called Looking at the Class (LC), which can be adapted by any rule-based AC algorithm. Unlike the traditional Classification based on Association rule (CBA) training method, which joins disjoint itemsets regardless of their class labels, our method joins only itemsets with similar class labels during the training phase. This prevents the accumulation of too many unnecessary merging during learning, and consequently results in huge saving (58%-91%) with reference of computational time and memory on large datasets.
Joint frequency ambiguity resolution and accurate timing estimation in OFDM systems with multipath fading
Authors: Jun Li, Guisheng Liao, Shan Ouyang
Venue: EURASIP Journal on Wireless Communications and Networking (2006)

A serious disadvantage of orthogonal frequency-division multiplexing (OFDM) is its sensitivity to carrier frequency offset (CFO) and timing offset (TO). For many low-complexity algorithms, the estimation ambiguity exists when the CFO is greater than one or two subcarrier spacing, and the estimated TO is also prone to exceeding the ISI-free interval within the cyclic prefix (CP). This paper presents a method for joint CFO ambiguity resolution and accurate TO estimation in multipath fading. Maximum-likelihood (ML) principle is employed and only one pilot symbol is needed. Frequency ambiguity is resolved and accurate TO can be obtained simultaneously by using the fast Fourier transform (FFT) and one-dimensional (1D) search. Both known and unknown channel order cases are considered. Computer simulations show that the proposed algorithm outperforms some others in the multipath fading channels.
Closure and stable Hamiltonian properties in claw-free graphs
Authors: Stephan Brandt, Odile Favaron, Zdeněk Ryjáček
Venue: Journal of Graph Theory (2000)

In the class of k-connected claw-free graphs, we study the stability of some Hamiltonian properties under a closure operation introduced by the third author. We prove that (i) the properties of pancyclicity, vertex pancyclicity and cycle extendability are not stable for any k (i.e., for any of these properties there is an infinite family of graphs Gk of arbitrarily high connectivity k such that the closure of Gk has the property while the graph Gk does not); (ii) traceability is a stable property even for k = 1; (iii) homogeneous traceability is not stable for k = 2 (although it is stable for k = 7). The article is concluded with several open questions concerning stability of homogeneous traceability and Hamiltonian connectedness. &copy; 2000 John Wiley & Sons, Inc. J Graph Theory 34: 30&ndash;41, 2000
A New Dynamic Scheme for Efficient RTS Threshold Handling in Wireless Networks
Authors: Mostafa Mjidi, Debasish Chakraborty, Naoki Nakamura, Kazuhide Koide, Atushi Takeda, Norio Shiratori
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications (2008)

Wireless network is an essential and integral part of the ubiquitous environment. For efficient access control, two different transmission schemes are used: The Basic Carrier Sensing Multiple Access with Collision Avoidance (CSMA/CA) and Request-To-Send/ Clear-To-Send (RTS/CTS) handshaking. The RTS/CTS handshaking addresses the hidden terminal problem as well as reduces the chance of collision in case of higher node density and traffic. However, in networks with low density, basic scheme would lead to higher throughput due to its less overhead. Efficient switching between these two schemes is imperative to maximize the throughput. We have first investigated to find a meaningful threshold value according to the network situation. The proposed algorithm then dynamically adjusts RTS Threshold according to the packet delivery ratio, which is an indicator of network traffic and shows a significant improvement over existing CSMA/CA and RTS/CTS schemes. Our adaptive scheme performed even better when data rates increases. We verify our proposed scheme with extensive network simulation using ns-2.
You Installed Internet Security on Your Network: Is Your Company Safe?
Authors: Ryan Sherstobitoff, Pedro Bustamante
Venue: Information Systems Security (2007)

Cyber-crime and malware has evolved so drastically over the last two years that it is a challenge for an IT professional to stay on top of recent malware trends and technological advances in cyber-security. This paper provides a look from inside the antivirus laboratory at current malware attacks and technology developments for effective defenses.
A stopping criterion for active learning
Authors: Andreas Vlachos
Venue: Computer Speech and Language (2008)

Active learning (AL) is a framework that attempts to reduce the cost of annotating training material for statistical learning methods. While a lot of papers have been presented on applying AL to natural language processing tasks reporting impressive savings, little work has been done on defining a stopping criterion. In this work, we present a stopping criterion for active learning based on the way instances are selected during uncertainty-based sampling and verify its applicability in a variety of settings. The statistical learning models used in our study are support vector machines (SVMs), maximum entropy models and Bayesian logistic regression and the tasks performed are text classification, named entity recognition and shallow parsing. In addition, we present a method for multiclass mutually exclusive SVM active learning.
Kernels, regularization and differential equations
Authors: Florian Steinke, Bernhard Schölkopf
Venue: Pattern Recognition (2008)

Many common machine learning methods such as support vector machines or Gaussian process inference make use of positive definite kernels, reproducing kernel Hilbert spaces, Gaussian processes, and regularization operators. In this work these objects are presented in a general, unifying framework and interrelations are highlighted. With this in mind we then show how linear stochastic differential equation models can be incorporated naturally into the kernel framework. And vice versa, many kernel machines can be interpreted in terms of differential equations. We focus especially on ordinary differential equations, also known as dynamical systems, and it is shown that standard kernel inference algorithms are equivalent to Kalman filter methods based on such models. In order not to cloud qualitative insights with heavy mathematical machinery, we restrict ourselves to finite domains, implying that differential equations are treated via their corresponding finite difference equations.
Meta-Service Organization for a Pervasive University
Authors: Raphael Zender, Enrico Dressler, Ulrike Lucke, Djamshid Tavangarian
Venue: Proceedings of the 2008 Sixth Annual IEEE International Conference on Pervasive Computing and Communications (2008)

SOA services afford a uniform and transparent use of different devices with similar functionalities. In the last years a number of, mostly incompatible, SOA technologies have been established. Therefore, this advantage is no longer true. Indeed it is not required to support the specific device, but the concrete SOA technology. Furthermore, a transparent service discovery is prevented by device interconnections because many SOA technologies use IP multicasts for a service discovery. The discovery range is limited on the consumer's subnet as the most routers don't route multicasts.This article describes a service discovery approach, that is independent from concrete SOA technologies and device interconnections. That results in an increase of available services and the service discovery range.
An optimal algorithm for intersecting line segments in the plane
Authors: B. Chazelle
Venue: Proceedings of the 29th Annual Symposium on Foundations of Computer Science (1988)

The authors present the first optimal algorithm for the following problem: given n line segments in the plane, compute all k pairwise intersections in O(n log n+k) time. Within the same asymptotic cost the algorithm will also compute the adjacencies of the planar subdivision induced by the segments, which is a useful data structure for contour-filling on raster devices.
The formalism underlying EASYMAP: A precompiler for refinement-based exploration of hierarchical data organizations
Authors: Edgar G. Daylight, Arnout Vandecappelle, Francky Catthoor
Venue: Science of Computer Programming (2008)

In the computer science community, data structure design is mainly conducted at a high level of abstraction under the implicit assumption that the platform contains a monolithic memory. Exploiting platform-related knowledge such as available on-chip and off-chip memory sizes, the cache size, and the number of SDRAM banks is mainly conducted in the system engineering community when the refined data structure has already been chosen. A convergence of both communities is desirable since this can lead to powerful optimizations. To achieve the convergence mentioned above, data-related transformations have been researched extensively in the recent past. Many of these transformations have a direct and large impact on memory footprint, execution time and energy consumption. Unfortunately, however, the most effective transformations are applied manually (e.g. in C code) and these result in a very time-consuming and error-prone design process. To overcome this burden, our general research goal is to develop a computer-aided design tool, called EASY MAP, that helps the designer to correctly construct the C code of an efficient but difficult-to-understand data structure. The formal design of EASY MAP is the topic of this article with the emphasis on Cha, the internal language of EASY MAP. Cha is based on a novel extension of Separation Logic's spatial conjunction operator (*), allowing it to concisely describe access operations of an irregularly accessed complex data organization. Cha is the basic building block of EASY MAP; it serves the purpose of automating EASY MAP's refinement process and proving that it is correct by construction.
A matrix product accelerator for field programmable systems on chip
Authors: Paolo Zicari, Pasquale Corsonello, Stefania Perri, Giuseppe Cocorullo
Venue: Microprocessors Microsystems (2008)

This paper presents a novel architecture for matrix multiplication optimized to be integrated as a coprocessor unit with embedded processors in modern FPGAs. In contrast with previous proposals that accelerate just the matrix multiplication computation, the coprocessor here proposed has been purposely designed to exploit an efficient communication protocol for the data exchange between it and the host processor that significantly reduces the whole computational time. The complete system formed by a 32-bit RISC processor augmented by the proposed coprocessor unit has been hardware implemented. Such system can be easily used to accelerate matrix multiplication with virtually any matrix sizes. Simulation tests and measurements demonstrate that the system requires a number of clock cycles more than halved, with respect to competitive solutions.
Performance of a Strategy Based Packets Forwarding in Ad Hoc Networks
Authors: Marcin Seredynski, Pascal Bouvry, Mieczyslaw A. Klopotek
Venue: Proceedings of the 2008 Third International Conference on Availability, Reliability and Security (2008)

A reliable wireless ad hoc network has to be secured against a selfish behavior. In such a network environment nodes have no incentives to participate actively in packet forwarding. Thus, selfishness is a rational choice for network participants. In this paper we demonstrate how using a strategy based packet forwarding approach can increase throughput in such networks and at the same time can minimize the usage of resources of participating nodes. The strategy defines conditions under which packets are being forwarded. It is based on the notions of trust and activity of the node originating the packet. We demonstrate that selfish behavior becomes unattractive when a certain number of nodes are using this approach. A genetic algorithm (GA) is applied to evolve good strategies, while for evaluation purposes of the strategies a game theoretical model of the ad hoc network is used.
Heavy cycles passing through some specified vertices in weighted graphs
Authors: Jun Fujisawa, Kiyoshi Yoshimoto, Shenggui Zhang
Venue: Journal of Graph Theory (2005)

A weighted graph is one in which every edge e is assigned a nonnegative number, called the weight of e. The sum of the weights of the edges incident with a vertex &upsilon; is called the weighted degree of &upsilon;. The weight of a cycle is defined as the sum of the weights of its edges. In this paper, we prove that: (1) if G is a 2-connected weighted graph such that the minimum weighted degree of G is at least d, then for every given vertices x and y, either G contains a cycle of weight at least 2d passing through both of x and y or every heaviest cycle in G is a hamiltonian cycle, and (2) if G is a 2-connected weighted graph such that the weighted degree sum of every pair of nonadjacent vertices is at least s, then for every vertex y, G contains either a cycle of weight at least s passing through y or a hamiltonian cycle. AMS classification: 05C45 05C38 05C35. &copy; 2005 Wiley Periodicals, Inc. J Graph Theory
Fast scan algorithms on graphics processors
Authors: Yuri Dotsenko, Naga K. Govindaraju, Peter-Pike Sloan, Charles Boyd, John Manferdelli
Venue: Proceedings of the 22nd annual international conference on Supercomputing (2008)

Scan and segmented scan are important data-parallel primitives for a wide range of applications. We present fast, work-efficient algorithms for these primitives on graphics processing units (GPUs). We use novel data representations that map well to the GPU architecture. Our algorithms exploit shared memory to improve memory performance. We further improve the performance of our algorithms by eliminating shared-memory bank conflicts and reducing the overheads in prior shared-memory GPU algorithms. Furthermore, our algorithms are designed to work well on general data sets, including segmented arrays with arbitrary segment lengths. We also present optimizations to improve the performance of segmented scans based on the segment lengths. We implemented our algorithms on a PC with an NVIDIA GeForce 8800 GPU and compared our results with prior GPU-based algorithms. Our results indicate up to 10x higher performance over prior algorithms on input sequences with millions of elements.
The Product Engineering Class in the Software Safety Risk Taxonomy for Building Safety-Critical Systems
Authors: Janice Hill, Daniel Victor
Venue: Proceedings of the 19th Australian Conference on Software Engineering (2008)

When software safety requirements are imposed on legacy safety-critical systems, retrospective safety cases need to be formulated as part of recertifying the systems for further use and risks must be documented and managed to give confidence for reusing the systems. The SEI Software Development Risk Taxonomy [4] focuses on general software development issues. It does not, however, cover all the safety risks. The Software Safety Risk Taxonomy [8] was developed which provides a construct for eliciting and categorizing software safety risks in a straightforward manner. In this paper, we present extended work on the taxonomy for safety that incorporates the additional issues inherent in the development and maintenance of safety-critical systems with software. An instrument called a Software Safety Risk Taxonomy Based Questionnaire (TBQ) is generated containing questions addressing each safety attribute in the Software Safety Risk Taxonomy. Software safety risks are surfaced using the new TBQ and then analyzed. In this paper we give the definitions for the specialized Product Engineering Class within the Software Safety Risk Taxonomy. At the end of the paper, we present the tool known as the ‘Legacy Systems Risk Database Tool’ that is used to collect and analyze the data required to show traceability to a particular safety standard.
Towards a computer algebraic algorithm for flat output determination
Authors: Felix Antritter, Jean Lévine
Venue: Proceedings of the twenty-first international symposium on Symbolic and algebraic computation (2008)

This contribution deals with nonlinear control systems. More precisely, we are interested in the formal computation of a so-called flat output, a particular generalized output whose property is, roughly speaking, that all the integral curves of the system may be expressed as smooth functions of the components of this flat output and their successive time derivatives up to a finite order (to be determined). Recently, a characterization of such flat output has been obtained in the framework of manifolds of jets of infinite order that yields an abstract algorithm for its computation. In this paper it is discussed how these conditions can be checked using computer algebra. All steps of the algorithm are discussed for the simple (but rich enough) example of a non holonomic car.
NAF, OAF, or noncooperation: which protocol to choose?
Authors: Ahmed Saadani, Olivier Traoré
Venue: EURASIP Journal on Advances in Signal Processing (2008)

The two main Amplify and Forward cooperative protocols are the orthogonal (OAF) and the nonorthogonal one (NAF). In this paper, we consider a given source, N relays, a destination, and a channel realization and we try to resolve the following problem: what is the best way to communicate: without cooperation or using one of the two cooperative protocols? This is equivalent to a power-sharing problem on the cooperation frame between source and relays aiming to the short-term channel capacity maximization. The obtained solution shows that cooperative protocol choice depends only on the available power at the relays. However the decision to cooperate depends on the channel conditions. We show that our power allocation scheme with relay selection improves the outage probability compared to the selective OAF and the NAF protocols and has a significant capacity gain.