ppxscal/embedding_network huggingface dataset:
A graph based routing algorithm for multi-hop cognitive radio networks
Authors: Yogesh R Kondareddy, Prathima Agrawal
Venue: Proceedings of the 4th Annual International Conference on Wireless Internet (2008)

Cognitive radio networks that allow dynamic spectrum access are considered spectrally more efficient than networks using fixed spectral allocation. These networks are characterized by dynamically changing channel sets at each node. The graph theoretic approach used in traditional multi-hop networks fails to efficiently model multi-hop cognitive radio networks and capture the required information for optimal routing. Hence, conventional graph-based routing protocols such as DSR or AODV cannot be used directly, for route discovery in such networks. In this paper, a unique multi-edge planar graph model for routing in such type of networks is proposed, which is quite simple and could be used in conjunction with any conventional graph-based routing protocol. The model is validated through simulations and the complexity of the model is shown to be lesser than an earlier layered graph model.
Geometric pattern matching for point sets in the plane under similarity transformations
Authors: Dror Aiger, Klara Kedem
Venue: Information Processing Letters (2009)

We consider the following geometric pattern matching problem: Given two sets of points in the plane, P and Q, and some (arbitrary) @d>0, find a similarity transformation T (translation, rotation and scale) such that h(T(P),Q)0 controls the approximation. Our approximation is on the size of the subset, B@?P, such that h(T(B),Q)(1-@e)|P| with high probability.
Integrating heterogeneous user interfaces in service oriented web applications
Authors: Matthias Tilsner, Adrian Fiech, Thomas Specht
Venue: Proceedings of the 2nd Canadian Conference on Computer Science and Software Engineering (2009)

Service Oriented Architecture (SOA) is a design framework that permits the developer to build complex applications from smaller modules called "services". When applying SOA to web applications, developers face several challenges. Among others, the heterogeneous user interfaces provided by these services must be adapted to fit into the larger application. This paper discusses approaches to automated adaptation of web application's layout and design. We review the range of web-based user interface modifications, suggest a technique that allows us the automated execution of the described steps and finally explore transparent integration of the modified user interfaces into a given web page flow (using a proxy server). Our approach relies on the proposed meta-language UDLD, which permits application providers to equip their user interfaces with semantic information about included components.
Identification of hysteretic behaviour of materials by using genetic algorithms
Authors: Veturia Chiroiu, Ligia Munteanu
Venue: Proceedings of the 10th WSEAS international conference on Automation & information (2009)

The paper is devoted to identification of the hysteresis behavior of nonlinear mesoscopic materials (NM) by using genetic algorithms. A NM material is an aggregate of grains which act as rigid vibrating units, while the contacts between them - the bond system constitute a set of interfaces that control the behavior of the material. The interfaces are mesoscopic, with a typical size of 1micrometer. In this paper we propose a friction contact model for the interface between moving grains that involve both tangential and normal relative motions. The proposed strategy is capable to predict the transition between stick, slip and separation of grains. The analysis of the hysteretic response of the NM material subjected to cyclic loading is given by application of the Preisach model and a genetic algorithm.
Non-metric multidimensional scaling (nmds) as a basis for a plant functional group classification and a bayesian belief network formulation for california oak woodlands
Authors: Maximo Alonso Valdes
Venue:  (2008)

One of the main goals of rangeland management is to sustain or obtain a specific plant community composition. Thus, rangeland management requires not only a good characterization of the plant community under management, but also a fairly good prediction of the response of that community to management actions. In this research on California oak woodlands we sampled 455 100-m transects both in the Coast Range and Sierra Nevada Foothill areas during the growing seasons of 2004 and 2005. Each transect site was characterized by its management history, disturbance frequency, soil characteristics and precipitation. Non-metrical multidimensional scaling (NMDS) and cluster analysis were combined to identify and classify the current most common plant communities. These communities and their canonical and spatial distribution were also analyzed using a plant functional group (PFG) approach. Finally, prior knowledge and observational data were combined in a Bayesian belief network to generate predictions about the woody species composition under different levels of precipitation and grazing. Our results indicate that the plant community composition on California oak woodlands is not a random assemblage of species. They also indicate that Quercus douglasii, Q. wislizeni and Pinus sabiniana are homogeneously distributed in the Coast Range and Sierra Nevada Foothills. Q. lobata and Q. kelloggii are mostly, and Q. agrifolia and Q. garryana are only present in the Coast Range. The distribution of the PFG's along precipitation and elevation gradients is not random. Evergreen species are located principally in the northern counties, whereas in the southern counties the predominant species are deciduous and adapted to dry conditions. Precipitation, soil available water capacity, elevation, slope and exposure are the most important variables in explaining the variability in the woody species composition. The probability of occurrence of Q. wislizeni, P. sabiniana, Q. kelloggii, and Q. garryana increases dramatically with precipitation. Grazing increases the probability of occurrence of Q. douglasii and Q. wislizeni; does not affect Q. lobata; and decreases the probability of finding P. sabiniana, Q. agrifolia, Q. garryana, and most of the shrubs. Further studies are needed to transform these patterns of distribution in quantitative rules of plant community assemblages. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Preemptive priority-based algorithms for fuzzy minimal cost flow problem: An application in hazardous materials transportation
Authors: Mehdi Ghatee, S. Mehdi Hashemi, M. Zarepisheh, E. Khorram
Venue: Computers and Industrial Engineering (2009)

This paper studies the minimal cost flow problem (MCFP) with fuzzy link costs, say fuzzy MCFP, to understand the effect of uncertain factors in applied shipment problems. With respect to the most possible case, the worst case and the best case, the fuzzy MCFP can be converted into a 3-objective MCFP. Applying a lexicographical ordering on the objective functions of derived problem, two efficient algorithms are provided to find the preemptive priority-based solution(s), namely p-successive shortest path algorithm and p-network simplex algorithm. In both of them, lexicographical comparison is used which is a natural ordering in many real problems especially in hazardous material transportation where transporting through some links jeopardizes people's lives. The presented schemes maintain the network structure of problem and so, they are efficiently implementable. A sample network is also given to illustrate the procedure and to compare the computational experiences with those of previously established works. Finally, the presented approach is applied to find an appropriate plan to transit hazardous materials in Khorasan roads network using annual data of accidents.
Multi-Fourier spectra descriptor and augmentation with spectral clustering for 3D shape retrieval
Authors: Atsushi Tatsuma, Masaki Aono
Venue: The Visual Computer: International Journal of Computer Graphics (2009)

We propose a new method of similarity search for 3D shape models, given an arbitrary 3D shape as a query. The method features the high search performance enabled in part by our unique feature vector called Multi-Fourier Spectra Descriptor (MFSD), and in part by augmenting the feature vector with spectral clustering. The MFSD is composed of four independent Fourier spectra with periphery enhancement. It allows us to faithfully capture the inherent characteristics of an arbitrary 3D shape object regardless of the dimension, orientation, and original location of the object when it is first defined. Given a 3D shape database, the augmentation with spectral clustering is done first by computing the p-minimum spanning tree of the whole data set, where p is a number usually much less than m, the size of the whole 3D shape data set. We then define the affinity matrix, which is a square matrix of size m by m, where each element of the matrix denotes the distance between two shape objects. The distance is computed in advance by traversing the p-minimum spanning tree. The eigenvalue decomposition is then applied to the affinity matrix to reduce dimensionality of the matrix, followed by grouping into k clusters. The cluster information is kept for augmenting the search performance when a query is given. With a series of benchmark data sets, we will demonstrate that our approach outperforms previously known methods for 3D shape retrieval.
A Personal Web Information/Knowledge Retrieval System
Authors: Hao Han, Takehiro Tokuda
Venue: Proceeding of the 2008 conference on Information Modelling and Knowledge Bases XIX (2008)

The Web is the richest source of information and knowledge. Unfortunately the current structure of Web pages makes it difficult for users to retrieve the information or knowledge in a systematic way. In this paper, using the tree approach, we propose a personal Web information/knowledge retrieval system for the extraction of structured parts from Web pages. First we get the layout pattern and paths of extraction parts of a typical Web page in target sites. Then we use the recorded layout pattern and paths to extract the structured parts from the rest of Web pages in target sites. We show the usefulness of our approach using the results of extracting structured parts of notable Web pages.
k-Anonymous data collection
Authors: Sheng Zhong, Zhiqiang Yang, Tingting Chen
Venue: Information Sciences: an International Journal (2009)

To protect individual privacy in data mining, when a miner collects data from respondents, the respondents should remain anonymous. The existing technique of Anonymity-Preserving Data Collection partially solves this problem, but it assumes that the data do not contain any identifying information about the corresponding respondents. On the other hand, the existing technique of Privacy-Enhancing k-Anonymization can make the collected data anonymous by eliminating the identifying information. However, it assumes that each respondent submits her data through an unidentified communication channel. In this paper, we propose k-Anonymous Data Collection, which has the advantages of both Anonymity-Preserving Data Collection and Privacy-Enhancing k-Anonymization but does not rely on their assumptions described above. We give rigorous proofs for the correctness and privacy of our protocol, and experimental results for its efficiency. Furthermore, we extend our solution to the fully malicious model, in which a dishonest participant can deviate from the protocol and behave arbitrarily.
Direct estimation of class membership probabilities for multiclass classification using multiple scores
Authors: Kazuko Takahashi, Hiroya Takamura, Manabu Okumura
Venue: Knowledge and Information Systems (2009)

Accurate estimation of class membership probability is needed for many applications in data mining and decision-making, to which multiclass classification is often applied. Since existing methods for estimation of class membership probability are designed for binary classification, in which only a single score outputted from a classifier can be used, an approach for multiclass classification requires both a decomposition of a multiclass classifier into binary classifiers and a combination of estimates obtained from each binary classifier to a target estimate. We propose a simple and general method for directly estimating class membership probability for any class in multiclass classification without decomposition and combination, using multiple scores not only for a predicted class but also for other proper classes. To make it possible to use multiple scores, we propose to modify or extend representative existing methods. As a non-parametric method, which refers to the idea of a binning method as proposed by Zadrozny et al., we create an &#x201c;accuracy table&#x201d; by a different method. Moreover we smooth accuracies on the table with methods such as the moving average to yield reliable probabilities (accuracies). As a parametric method, we extend Platt&#x2019;s method to apply a multiple logistic regression. On two different datasets (open-ended data from Japanese social surveys and the 20 Newsgroups) both with Support Vector Machines and naive Bayes classifiers, we empirically show that the use of multiple scores is effective in the estimation of class membership probabilities in multiclass classification in terms of cross entropy, the reliability diagram, the ROC curve and AUC (area under the ROC curve), and that the proposed smoothing method for the accuracy table works quite well. Finally, we show empirically that in terms of MSE (mean squared error), our best proposed method is superior to an expansion for multiclass classification of a PAV method proposed by Zadrozny et al., in both the 20 Newsgroups dataset and the Pendigits dataset, but is slightly worse than the state-of-the-art method, which is an expansion for multiclass classification of a combination of boosting and a PAV method, on the Pendigits dataset.
Paired professional development: a methodology for continued professional development in computer science
Authors: Walter M. Pharr, Christopher W. Starr, Caroline S. Starr
Venue: ACM SIGCSE Bulletin (2009)

We describe a study group methodology called paired professional development (PPD) for use by faculty members for continuing education. The methodology brings exactly two colleagues together for cooperative study within a topic area over an extended period of time. Paired professional development is grounded in the practice of study groups, collaborative learning and high-impact educational practices, and is similar to pair programming in structure and benefits.
Is there a best color space for color image characterization or representation based on Multivariate Gaussian Mixture Model?
Authors: Olivier Alata, Ludovic Quintard
Venue: Computer Vision and Image Understanding (2009)

The aim of this work is the evaluation of Multivariate Gaussian Mixture Model (MGMM) in different color spaces (RGB, L*a*b* and YC1C2 issued from IHLS). We have analysed the approach for the description of the color information in an image on the one hand and for the representation of a color image on the other hand. To achieve this goal we need an accurate estimation method of MGMM parameter set firstly and distances for evaluating MGMMs secondly. A SEMmean-EM procedure and two distances between color images and synthesized images are then proposed. First distance is based on normalized histograms and second distance is based on a psychovisual distance between two colors. To compute these distances, two methods for synthezising images are proposed from a direct procedure of site classification: for each site, sample a color from its associated multivariate Gaussian law or attribute the mean color. The conclusion of our study is that estimation accuracy is better using L*a*b* color space than using RGB or YC1C2 and discrimination performances based on the two distances are also better in L*a*b* color space. A comparison between different criteria for choosing the number of components in the mixture is also done. Integrated Completed Likelihood criterion may be used if one only needs to characterize color information and Bayesian Information Criterion or @f"@b"""m"""i"""n criterion may be used if one needs to characterize color information along with color spatial localization.
Knowledge distribution in e-maintenance activities
Authors: Anne Garcia, Daniel Noyes, Philippe Clermont
Venue: Proceeding of the 2008 conference on Collaborative Decision Making: Perspectives and Challenges (2008)

This communication deals with the implication of the intangible resources required to maintenance operations (knowledge and skill) and, more particularly, for their localization relative to the implementation site. The performance of the maintenance function is directly indexed with the availability of knowledge-related resources which are required. We study the performance effects of the local and external (via the e-service) knowledge distribution. A formulation of the problem is elaborated to evaluate the e-maintenance impact at these situations, preceding a step of optimization. A simulation tool is suggested in order to model e-maintenance situations and to evaluate the knowledge availability required to maintenance operations. We present the principle of the simulator with the implication of one actor of maintenance and with the combined implication of two actors.
A new approach for analyzing the limiting behavior of the normalized LMS algorithm under weak assumptions
Authors: Eweda Eweda
Venue: Signal Processing (2009)

This paper presents a new and simple approach to analyzing the limiting behavior of the normalized LMS algorithm under weak assumptions. No restrictions are made on the dependence between successive regressors, the dependence among the regressor elements, the length of the adaptive filter, or the distribution types of the filter input and the noise. The analysis holds for all values of the algorithm step-size in the range between 0 and 2. The analysis is carried out using a new performance measure, based on the time evolution of the component of the weight deviation vector in the direction of the regressor. This component is termed as the effective weight deviation since it is the only component that contributes to the excess estimation error at the output of the adaptive filter. The paper derives upper bounds for the long-term averages of the mean-square effective weight deviation, mean absolute excess estimation error, and of the mean-square excess estimation error. The analytical results of the paper are supported by simulations.
Analysis of antireciprocity on hall effect-structured gyrators
Authors: Dan George Tont, Mihaiela Iliescu, Gabriela Tont
Venue: Proceedings of the 10th WSEAS international conference on Mathematical and computational methods in science and engineering (2008)

The antireciprocity of the Hall transducer is a natural phenomenon and its results from investigation of transfer resistances. Is known that for a certain value of magnetic induction, in general, transfer resistances are not equal. In other words, Hall transducer is a passive non-reciprocal circuit. In certain circumstances, however, when Hall plate does have voltage zero, (constructively, electrodes are disposed on the same equipotential surface with zero inductance) transfer resistances are equal in value, but have opposite sign. In these cases we are talking about behavior of Hall transducer as antireciprocal circuit, respectively as a gyrator. Gyrators are a class of antireciprocal resistive two-ports. The paper focuses on the analysis of characteristics of driving point impedance for a lossy gyrator. For a gyrator, the ratio between short-circuit input resistance and open-circuit input resistance is always greater then unity. Based on the value of this ratio compared to unity, a new taxonomy of two-ports is proposed. The findings are concerning and the locus of the input equivalent impedance An assessment of Hall generator behavior regarded as a circuit element and particularly as a gyrator was performed by the means of experimentally validation Onsager-Casimir relation.
An evidential knowledge representation for drug-mechanisms and its application to drug safety
Authors: Ira Kalet
Venue:  (2008)

A major challenge to designers of informatics tools that help alert clinicians to potential drug-drug interactions (DDIs) is how to best assist clinicians when they must infer the potential risk of an adverse event between medication combinations that have not been studied together in a clinical trial. The central thesis of this dissertation is that DDI prediction using drug mechanism knowledge can help drug-interaction knowledge bases expand their coverage beyond what has been tested in clinical trials while avoiding prediction errors that occur when individual drug differences are not recognized. This dissertation describes a knowledge representation system, called the Drug Interaction Knowledge Base (DIKB), that uses a novel approach to linking and assessing evidence support for drug-mechanism assertions. The DIKB is the first knowledge-representation system we are aware of to use a computable model of evidence and a Truth Maintenance System to manage assertions in its knowledge-base. The novel approach to evidence management implemented in the DIKB enables its prediction accuracy and coverage to be optimized to a particular body of evidence; a feature that is very desirable for clinical decision support. The DIKB is also novel for its computable representation of the conjectures behind a specific application of evidence. These evidence-use assumptions enable the system to flag when a conjecture has become invalid and alert knowledge-base maintainers to the need to reassess their original interpretation of what assertions a piece of evidence supports. They are also used as evidence is input into the system to help identify a pattern, called a circular line of evidence support, that is indicative of fallacious reasoning by evidence-base curators. The DIKB has been shown capable of accurately predicting clinically-relevant DDIs using only pharmacokinetic drug-mechanism knowledge and development of the system has helped to identify and evaluate potential informatics solutions to the challenges of representing, synthesizing, and maintaining drug mechanism knowledge.
Providing two-dimensional tactile directional information with one-dimensional movement
Authors: Jani Lylykangas, Veikko Surakka, Jussi Rantala, Roope Raisamo
Venue: Proceedings of the World Haptics 2009 - Third Joint EuroHaptics conference and Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems (2009)

This paper presents a new approach to provide two-dimensional directional information mediated by the sense of touch. The basic idea was to test whether one-dimensional stimuli provided by a counterclockwise (CCW) and clockwise (CW) rotating leadscrew of a friction-based fingertip stimulator prototype can be perceived as two-dimensional directional information. Ten participants were asked to indicate the perceived direction of the stimuli in left-right (i.e., mediolateral) and forward-backward (i.e., anteroposterior) dimensions. The properties of 12 stimuli were varied, for example, by rotation direction (i.e., CCW and CW) and stimulus symmetry (i.e., symmetrical and asymmetrical). The results showed that left and right directions were perceived in accuracies of ≥ 90%. Forward and backward directions could be perceived above the chance level. Based on the results we suggest that the concept could be used successfully in presenting at least three directions (i.e., left, right, and backward). For navigation applications three directions would, in many cases, be sufficient, but by means of further studies it might be possible to provide information of all four main directions.