ppxscal/embedding_network huggingface dataset:
New upper bounds in Klee's measure problem
Authors: M. H. Overmars
Venue: Proceedings of the 29th Annual Symposium on Foundations of Computer Science (1988)

New upper bounds are given for the measure problem of V. Klee (1977) that significantly improve the previous bounds for dimensions greater than 2. An O(n/sup d/2/ log n, n) time-space upper bound to compute the measure of a set of n boxes in Euclidean d-space is obtained. The solution requires several novel ideas including application of the inclusion/exclusion principle, the concept of trellises, streaming, and a partition of d-space.
Anisotropic error control for environmental applications
Authors: Luca Dedè, Stefano Micheletti, Simona Perotto
Venue: Applied Numerical Mathematics (2008)

In this paper we aim at controlling physically meaningful quantities with emphasis on environmental applications. This is carried out by an efficient numerical procedure combining the goal-oriented framework [R. Becker, R. Rannacher, An optimal control approach to a posteriori error estimation in finite element methods, Acta Numer. 10 (2001) 1-102] with the anisotropic setting introduced in [L. Formaggia, S. Perotto, New anisotropic a priori error estimates, Numer. Math. 89 (2001) 641-667]. A first attempt in this direction has been proposed in [L. Formaggia, S. Micheletti, S. Perotto, Anisotropic mesh adaptation in computational fluid dynamics: application to the advection-diffusion-reaction and the Stokes problems, Appl. Numer. Math. 51 (2004) 511-533]. Here we improve this analysis by carrying over to the goal-oriented framework the good property of the a posteriori error estimator to depend on the error itself, typical of the anisotropic residual based error analysis presented in [G. Maisano, S. Micheletti, S. Perotto, C.L. Bottasso, On some new recovery based a posteriori error estimators, Comput. Methods Appl. Mech. Engrg. 195 (37-40) (2006) 4794-4815; S. Micheletti, S. Perotto, An anisotropic recovery-based a posteriori error estimator, in: F. Brezzi, A. Buffa, S. Corsaro, A. Murli (Eds.), Numerical Mathematics and Advanced Applications-ENUMATH2001, Proceedings of the 4th European International Conference on Numerical Mathematics and Advanced Applications, Springer-Verlag, Italia, 2003, pp. 731-741]. On the one hand this dependence makes the estimator not immediately computable; nevertheless, after approximating this error via the Zienkiewicz-Zhu gradient recovery procedure [O.C. Zienkiewicz, J.Z. Zhu, A simple error estimator and adaptive procedure for practical engineering analysis, Internat. J. Numer. Methods Engrg. 24 (2) (1987) 337-357; O.C. Zienkiewicz, J.Z. Zhu, The superconvergent patch recovery and a posteriori error estimates. Part 1: The recovery technique, Internat. J. Numer. Methods Engrg. 33 (1992) 1331-1364], the resulting estimator is expected to exhibit a higher convergence rate than the one in [L. Formaggia, S. Micheletti, S. Perotto, Anisotropic mesh adaptation in computational fluid dynamics: application to the advection-diffusion-reaction and the Stokes problems, Appl. Numer. Math. 51 (2004) 511-533]. As the broad numerical validation attests, the proposed estimator turns out to be more efficient in terms of d.o.f.'s per accuracy or equivalently, more accurate for a fixed number of elements.
Educational program in cardiac sounds
Authors: Gisele Grinevicius Garbe, Gustavo Freschi, Cristiano Acierno Varella, Daniel Lico dos Anjos Afonso, Rogério Furquim Mauad, Keith Chen de Christo, Monica Parente Ramos, Luiz Antonio Ribeiro de Moura, Daniel Sigulem
Venue: Proceedings of the 2007 Euro American conference on Telematics and information systems (2007)

Medical school has been through several modifications until it reached its current model. However, with its development and the introduction of new teaching techniques that aims to move students towards actual medical practice, instead of just delivering course content, some problems began to emerge. For example, in some situations, students cannot learn by a patient analysis because that could be considered an invasive process, involving high risk procedures and ethical issues. Nevertheless, the difficulties found in medical education cannot hinder the process of educating new doctors. Thus, it is necessary to use appropriate educational methods and technologies. An incipient technology is the utilization of multimedia educational programs, which integrate multimedia resources and offer the user an active participation in the learning process. An educational program, discussing the pathological and physiological aspects in cardiology, is in implementation on UNIFESP's distance education website, in which we are also going to assess the use of handheld computers, or PDAs, by health students. These devices are potentially useful in distance education and offer several benefits, being the reduced size its main feature.
Study and Computer Aided Analysis on a New Biomedical Auto-Suture Apparatus
Authors: Jeremy (Zheng) Li, Sharon Wang
Venue: Proceedings of the 2008 International Conference on BioMedical Engineering and Informatics - Volume 02 (2008)

This paper introduces a new biomedical apparatus for applying surgical clips to patients’ tissue or vessel. During surgical process, the apparatus jaw is placed around the vessel or tubular structure. As handles of apparatus are brought together, the clip is closed around the vessel to stop bleeding. As handles are released, a new surgical clip is automatically loaded into the apparatus jaw. Compared with current surgical clip apparatus, this new design provides some potential features to help surgeons’ operational procedure, i.e. new mechanism designed to prevent surgical clip from accidentally shooting out when loaded into jaws, enhanced structure installed to prevent jaws from twist that can sever tissues, special supporting feature configured to prevent unexpected jaw closure when extra side-load exerted, and etc. The system is also analyzed by computerized simulation to prove its feasible function with proper mechanical advantage. The preliminary clinician’s evaluation indicated the feasibility of this instrument.
Product Line Sigraphs
Authors: Daniela Ferrero
Venue: Proceedings of the The International Symposium on Parallel Architectures, Algorithms, and Networks (2008)

Intuitively, a signed graph is a graph in which every edge is labeled with a + or - sign. For each edge, its sign represents the mode of the relationship between the vertices it joins.In a signed graph, cycles can be naturally given the sign corresponding to the product of its edges. Then, a signed graph is called balanced when all the cycles have positive sign. Balanced signed graph have multiple applications in the field of social networks. Consequently, there is a significant amount of research in the problem of determining if a signed graph is balanced or not. In particular, some authors investigated extensions to signed graph of the line graph and studied under what circumstances the signed graphs obtained are balanced or not.This paper presents a new operation, which is also an extension to signed graphs of the line graph, with the property that applied to any signed graph always produces a balanced signed graph.
External bounds and step controllability of the linear interval system
Authors: L. T. Ashchepkov
Venue: Automation and Remote Control (2008)

The differential equations describing double-sided bounds of the fundamental matrix of solutions for the linear control system with variable interval coefficients are obtained. Based on those bounds, the controllability problem, i.e., the possibility to transfer the system from a given parallelepiped to another in finite time in the class of step (piecewise constant) controls, is examined. Sufficient conditions of controllability in the form of solvability of an auxilliary linear programming problem are established. This problem results in step control transferring a bundle of system trajectories from an initial parallelepiped to a minimal neighborhood of a final parallelepiped.
Correctness Criteria for Normalization of Semistructured Data
Authors: Scott Uk-Jin Lee, Jing Sun, Gillian Dobbie, Lindsay Groves, Yuan Fang Li
Venue: Proceedings of the 19th Australian Conference on Software Engineering (2008)

The rapid increase in semistructured data usage has lead to the development of various database systems for semistructured data. Web services and applications that utilize large amounts of semistructured data require data to remain consistent and be stored efficient. Several normalization algorithms for semistructured database systems have been developed to satisfy these needs. However, these algorithms lack the verification that would ensure that data and constraints among the data are not lost or corrupted during normalization. In this paper, we propose a set of correctness criteria for normalization of semistructured data, which require that functional dependencies are preserved, data is not lost, and spurious data is not created during normalization. We use the Z specification language to provide a precise and declarative definition of our criteria.
Privacy Improvement through Pseudonymity in Parlay X for Location Based Services
Authors: Nabil Ajam, Ahmed Bouabdallah
Venue: Proceedings of the Seventh International Conference on Networking (2008)

Privacy constitutes a great challenge for the spread of new services. In particular for Next Generation Network (NGN) services, operators and providers hold more sensitive information than traditional networks. NGN implies a new service layer, accessible by third parties through standardized interfaces. This newly proposed service architecture is not protected yet against privacy threat. We demonstrate that pseudonymity is an interesting and feasible solution in Parlay X gateway.Location-Based Services (LBS) make use of user positions, which are sensitive information, to provide more enhanced services. Different alternatives in cellular networks, exist to retrieve this information, they however don't offer the same privacy quality level. Those alternatives may cooperate to provide location information to service providers. The discontinuity of the privacy quality imperils the anonymity of users. In this paper, we propose a novel Privacy web service added to the Parlay X gateway of the service architecture to ensure user privacy through pseudonymity in location services. The architecture is based on the enhancement of standardized Parlay X web services. The new proposed web service could enforce the privacy provided by operator networks. A formal model of our approach is investigated.
Ranking Categorical Features Using Generalization Properties
Authors: Sivan Sabato, Shai Shalev-Shwartz
Venue: The Journal of Machine Learning Research (2008)

Feature ranking is a fundamental machine learning task with various applications, including feature selection and decision tree learning. We describe and analyze a new feature ranking method that supports categorical features with a large number of possible values. We show that existing ranking criteria rank a feature according to the training error of a predictor based on the feature. This approach can fail when ranking categorical features with many values. We propose the Ginger ranking criterion, that estimates the generalization error of the predictor associated with the Gini index. We show that for almost all training sets, the Ginger criterion produces an accurate estimation of the true generalization error, regardless of the number of values in a categorical feature. We also address the question of finding the optimal predictor that is based on a single categorical feature. It is shown that the predictor associated with the misclassification error criterion has the minimal expected generalization error. We bound the bias of this predictor with respect to the generalization error of the Bayes optimal predictor, and analyze its concentration properties. We demonstrate the efficiency of our approach for feature selection and for learning decision trees in a series of experiments with synthetic and natural data sets.
A model to blend renderings
Authors: Vincent Boyer, Dominique Sobczyk
Venue: Machine Graphics Vision International Journal (2006)

We propose a model to blend renderings. It consists in mixing different kind of rendering techniques in the same frame to enhance the visualisation of information on large scenes. This method can be implemented in real-time during the rendering process using the GPU programming. Moreover, the rendering techniques used and the key points defined by the user can be interactively changed. In this paper we present the model, a new non-photorealistic rendering technique and images produced by our method.
Validation of chlorophyll fluorescence derived from MERIS on the west coast of Canada
Authors: J. Gower, S. King
Venue: International Journal of Remote Sensing (2007)

MERIS on Envisat provides images of above-atmosphere spectral radiance in 15 bands of the baseline spectral band-set. This set includes three bands centered at 665, 681 and 709 nm, placed to measure the fluorescence emission from chlorophyll a in marine and fresh water phytoplankton at 685 nm, stimulated by ambient sun and sky light. We compare the observed fluorescence signal levels with measurements of extracted chlorophyll from research cruises and buoy data during 2002 and 2003, and with satellite estimates of chlorophyll from the blue to green ratio observed by MERIS. We present an average relation between fluorescence and surface chlorophyll concentration based on a simple model accounting for absorption of stimulating and emitted radiation by chlorophyll pigments, which gives a first-order fit to the observations.
Learning for control from multiple demonstrations
Authors: Adam Coates, Pieter Abbeel, Andrew Y. Ng
Venue: Proceedings of the 25th international conference on Machine learning (2008)

We consider the problem of learning to follow a desired trajectory when given a small number of demonstrations from a sub-optimal expert. We present an algorithm that (i) extracts the---initially unknown---desired trajectory from the sub-optimal expert's demonstrations and (ii) learns a local model suitable for control along the learned trajectory. We apply our algorithm to the problem of autonomous helicopter flight. In all cases, the autonomous helicopter's performance exceeds that of our expert helicopter pilot's demonstrations. Even stronger, our results significantly extend the state-of-the-art in autonomous helicopter aerobatics. In particular, our results include the first autonomous tic-tocs, loops and hurricane, vastly superior performance on previously performed aerobatic maneuvers (such as in-place flips and rolls), and a complete airshow, which requires autonomous transitions between these and various other maneuvers.
Requirements-based test case specification by using information from model construction
Authors: Christian Pfaller
Venue: Proceedings of the 3rd international workshop on Automation of software test (2008)

In model-based testing a test case specification is used to determine the set of test cases to be generated automatically. This paper introduces a requirements-based test case specification which uses information gathered by reasoning about the construction of the model. The basic idea is to reason about the motivation why an element of the model was introduced. This reasoning about model construction leads to specific restrictions of the model for every requirement; the restricted models are used for requirements-based test case generation. The paper gives a formal specification of the requirements-based test case specification TSpecREQ based on Mealy machines and outlines its usage in a development process where the requirements specifications given by various stakeholders are considered as well.
Using model transformation to support model-based test coverage measurement
Authors: Leila Naslavsky, Hadar Ziv, Debra J. Richardson
Venue: Proceedings of the 3rd international workshop on Automation of software test (2008)

Adoption of model-driven development is leading to increased use of models jointly with source code for software testing, by means of Model-Based Testing (MBT). MBT uses models to derive concrete test cases to test code. With MBT, test adequacy criteria are described in relation to the models. They are used to evaluate reliability of derived test cases and as predictor for determining when to stop testing. Hence, when concrete test cases are executed, it is important to measure coverage achieved with regards to the model, rather than only to the code. This places new challenges for testing activities, which include creation and maintenance of relationships between model and code elements. To deal with such challenge, we propose an approach that leverages model-to-text transformation traceability techniques to create relationships required to measure model coverage achieved with test cases executions. We illustrate the approach by applying it to a small ATM example.
Wavelet representation of differentially fed ANN
Authors: R. Manjunath, K. S. Gurumurthy
Venue: Proceedings of the 2nd WSEAS International Conference on Electronics, Control and Signal Processing (2003)

The discrete wavelet transform is a multi-scale signal representation. Here it is shown that coarse form is equivalent to the approximated output and fine part to the differentially fed output or hyper planes. The wave let coefficients represent differential feedback planes. In this paper an overview of multiresolution analysis in differentially fed neural networks is given. It has been shown that the network closely resembles multiresolution of wavelet transform.
A cooperative content delivery scheme for multimedia services in contents delivery networks
Authors: Heejin Roh, Youn-Woo Kim, Kwang Sun Ko, Young Ik Eom
Venue: Proceedings of the 2nd international conference on Ubiquitous information management and communication (2008)

Contents Delivery Networks (CDNs) have been introduced to deliver efficiently very large content to user with low cost. For this, various content delivery schemes such as the uncooperative pull-based scheme, the cooperative push-based scheme, and the cooperative pull-based scheme, have been studied in CDNs. However, these schemes hold the problems such as temporary service interruption, the increases of the average delivery time of content and the bottlenecks to the Internet backbone. In this paper, we propose the content delivery scheme called the cooperative hybrid-based scheme that enables efficient operation of limited resources. Through simulation, we confirmed the service without temporary interruption, the average delivery time of content improved by up to 8%, and the bottlenecks to the Internet backbone between ISPs reduced by up to 66%.
Flexible Key Assignment for a Time-Token Constraint in a Hierarchy
Authors: Hsing-Chung Chen, Shiuh-Jeng Wang, Jyh-Horng Wen, Chung-Wei Chen
Venue: Proceedings of the 2008 International Conference on Multimedia and Ubiquitous Engineering (2008)

A scheme, which uses flexible key management upon time-token constraint for a user hierarchy access control (UHAC) scheme, is proposed in this paper. For adapting the changeability in a UHAC system, we propose a technique of assigning independent time-token which is distributed by a trusted agency server to reply an authorized user for once secure ac-cess request. The key feature of the technique is to adapt some secure parameters in distributed time-token for responding to each legal access request. Further, all class keys will be updated proactively by the concept of proactive key management, which makes the advan-tage that is proven and free from the scenario of the collusive attack example which proposed by Yi et al. in [14].
A Two-Layered Deployment Scheme for Wireless Sensor Network based Location Tracking
Authors: Werner Kurschl, Wolfgang Gottesheim, Stefan Mitsch, Rene Prokop, Johannes Schönböck, Wolfgang Beer
Venue: Proceedings of the Fifth International Conference on Information Technology: New Generations (2008)

The tracking of objects and humans has recently received a lot of attention as a tool to improve business processes, occupational, and public safety. In wireless sensor networks location information is needed to put sensor readings into geographical context. In industrial environments wireless sensor networks can facilitate deployment of tracking applications as they can establish a standalone communication infrastructure (so called mesh networks). Nevertheless the communication infrastructure and thus the tracking applications rely on radio transmission. Therefore problems like ambiguous locations and the neighboring-room problem known from other radio-based tracking solutions may occur. We propose a two layered deployment scheme for wireless sensor networks to overcome these limitations. It consists of a robust communication layer and a flexible location layer, which enable per room accuracy. Such accuracy is sufficient for many types of tracking applications.
Security Analysis and Implementation of JUIT—Image Based Authentication System Using Kerberos Protocol
Authors: Nitin, Durg Singh Chauhan, Vivek Kumar Sehgal, Ankit Mahanot, Pallavi Singh, Sohit Ahuja, Utkarsh Shrivastava, Manisha Rana, Vineet Punjabi, Shivam Vinay, Nakul Sharma
Venue: Proceedings of the Seventh IEEE/ACIS International Conference on Computer and Information Science (icis 2008) (2008)

Secure environments protect their resources against unauthorized access by enforcing access control mechanisms. So when increasing security is an issue text based passwords are not enough to counter such problems. The need for something more secure along with being user friendly is required. This is where Image Based Authentication (IBA) comes into play. IBA encapsulates Kerberos Protocol, Version 5, and provides clients a completely unique and secured authentication tool to work on. This paper is a comprehensive study on the subject of using images as the password set and the implementation of Jaypee University of Information Technology (JUIT) IBA system called as JUIT-IBA. This tool provides a secure channel of communication between the communicating entities. The assortment of image set as client’s password aims at thwarting Brute Force attacks, Shoulder attack, and Tempest attack at the client side while the attacks at the server side can be averted by putting into practice Kerberos protocol. It also describes how our system works along with the evaluation of its performances in different computing environments.