ppxscal/embedding_network huggingface dataset:
Organization detection for dynamic load balancing in individual-based simulations
Authors: Cyrille Bertelle, Antoine Dutot, Frédéric Guinand, Damien Olivier
Venue: Multiagent and Grid Systems (2007)

Large-scale individual-based simulations can benefit a lot from high performance computing environments. The benefit that can be hopped for depends greatly on a good load distribution among the processing resources together with the minimization of the communication overhead. However, minimizing both idle time and communication overhead requires the search for a trade-off. Inspired by complex systems, the approach described in this paper aims at minimizing the volume of data exchanged over the network between tasks of a distributed application, while balancing the load between available computing ressources. The method lies on the trail-laying trail-following paradigm used in algorithms based on artificial ants.
Comparison of different nano- and micro-focus X-ray computed tomography set-ups for the visualization of the soil microstructure and soil organic matter
Authors: S. Sleutel, V. Cnudde, B. Masschaele, J. Vlassenbroek, M. Dierick, L. Van Hoorebeke, P. Jacobs, S. De Neve
Venue: Computers Geosciences (2008)

This study explores the potential of different X-ray computed tomography (X-ray CT) set-ups for the discrimination of soil mineral matter, soil organic matter (OM) and the pore phase. Different X-ray sources, detectors and filtering methods were investigated. Use of a low-energy detector as well as a Cu-filter decreased the potential for phase segmentation in X-ray CT images of an artificial sand-OM mixture. A mid-range X-ray detector showed to hold more potential. Results obtained for an artificial sand-OM sample showed that an attenuation coefficient (AC) grey-value histogram-based single threshold was unsuitable for automated phase segmentation. A dual thresholding approach enabled a better separation of the different phases. Secondly, the minimal measurable pore size class in a clay loam soil aggregate was compared using micro-focus and state-of-the-art nano-focus X-ray CT. The resolution of the scanned images depends on the spot size of the X-ray source, the resolution of the detector and the magnification used. Reliable discrimination of pore and solid phases was expected to be limited by the X-ray tube's focal spot size to 2.5@mm, in contrast to the voxel size of 0.84@mm actually obtained using nano-focus CT. Although this study was limited in its extent, indications were found that more fine porosity is visible at higher resolutions and that large connected pore spaces may be observed. This fine porosity seems to be very locally autocorrelated. Further fundamental research into AC grey-value automated segmentation of OM from the mineral and pore phases, as well as the truly achievable minimal pore size class using artificial calibration samples, is necessary.
Nearly tight bounds for wormhole routing
Authors: A. Ranade
Venue: Proceedings of the 35th Annual Symposium on Foundations of Computer Science (1994)

We present nearly tight bounds for wormhole muting on Butterfly networks which indicate it is fundamentally different from store-and-forward packet routing. For instance, consider the problem of routing N log N (randomly generated) log N length messages from the inputs to the outputs of an N input Butterfly. We show that with high probability that this must take time at least /spl Omega/(log/sup 3/N/(log log N)/sup 2/). The best lower bound known earlier was /spl Omega/(log/sup 2/ N), which is simply the flit congestion an each link. Thus our lower bound shows that wormhole routing (unlike store-and-forward-routing) is very ineffective in utilizing communication links. We also give a routing algorithm which nearly matches our lower bound. That is, we show that with high probability the time is O(log/sup 3/ N log log N), which improves upon, the previous best bound of O(log/sup 4/ N). Our method also extends to other networks such as the two-dimensional mesh, where it is nearly optimal. Finally, we consider the problem of offline wormhole routing, where we give optimal algorithms for trees and multidimensional meshes.
Experimental and numerical characterization of a membrane material for orthotropic steel deck bridges: Part 1
Authors: T. O. Medani, X. Liu, M. Huurman, A. Scarpas, A. A. A. Molenaar
Venue: Finite Elements in Analysis and Design (2008)

Preliminary analyses have shown that membrane materials, connecting mastic asphalt surfacings to plates of orthotropic steel deck bridges, play an extremely important role in determining the structural response of these types of bridges. This necessitates search for a realistic representation of the behaviour of membrane materials. For this purpose, an extensive experimental program was carried out, and a non-linear constitutive model was developed to describe the behaviour of a membrane material. This is the first of two papers on characterization of the behaviour of a bituminous-based membrane material in an orthotropic steel deck bridge. In this paper, results of an experimental program executed on a membrane material will be presented. In this program, the TU-Delft four-point shear test was used to characterize the response of a membrane material to shear and normal forces. In particular, the influence of temperature, deformation rate and confinement on the shear strength, the shear stiffness and the deformation at failure are identified.
Extracting and composing robust features with denoising autoencoders
Authors: Pascal Vincent, Hugo Larochelle, Yoshua Bengio, Pierre-Antoine Manzagol
Venue: Proceedings of the 25th international conference on Machine learning (2008)

Previous work has shown that the difficulties in learning deep generative or discriminative models can be overcome by an initial unsupervised learning step that maps inputs to useful intermediate representations. We introduce and motivate a new training principle for unsupervised learning of a representation based on the idea of making the learned representations robust to partial corruption of the input pattern. This approach can be used to train autoencoders, and these denoising autoencoders can be stacked to initialize deep architectures. The algorithm can be motivated from a manifold learning and information theoretic perspective or from a generative model perspective. Comparative experiments clearly show the surprising advantage of corrupting the input of autoencoders on a pattern classification benchmark suite.
The fast scheme for document page segmentation in OCR using window and optimum image
Authors: Wichian Premchaiswadi, Phaisarn Sutheebanjard, Nuchree Premchaiswadi
Venue: Proceedings of the 5th WSEAS International Conference on Computational Intelligence, Man-Machine Systems and Cybernetics (2006)

This paper presents the speed-up method for document page segmentation which is one of the most important processes in an Optical Character Recognition (OCR) system. In this proposed scheme, a window size of 12 by 12 pixels is used to find a black pixel and its contour border. Then, the optimum image is created from these borders of characters where the 12×12 pixels of the original picture are represented by 1 pixel in the optimum image. Therefore, the number of pixels is reduced to 1/144 times the original image but still keeps the original image structure correctly. Finally, the optimum image is used for block extraction process to provide the faster work result. The experimental results show that the proposed scheme can significantly speed up the processing time of the document page segmentation process.
An asynchronous recurrent linear threshold network approach to solving the traveling salesman problem
Authors: E. J. Teoh, K. C. Tan, H. J. Tang, C. Xiang, C. K. Goh
Venue: Neurocomputing (2008)

In this paper, an approach to solving the classical Traveling Salesman Problem (TSP) using a recurrent network of linear threshold (LT) neurons is proposed. It maps the classical TSP onto a single-layered recurrent neural network by embedding the constraints of the problem directly into the dynamics of the network. The proposed method differs from the classical Hopfield network in the update of state dynamics as well as the use of network activation function. Furthermore, parameter settings for the proposed network are obtained using a genetic algorithm, which ensure a stable convergence of the network for different problems. Simulation results illustrate that the proposed network performs better than the classical Hopfield network for optimization.
Simulation, modelling and optimization for operative maintenance
Authors: Vasile Anghel, George Draghici
Venue: Proceedings of the 5th WSEAS International Conference on Computational Intelligence, Man-Machine Systems and Cybernetics (2006)

The paper proposes the achievement of a predictive maintenance conception for the operative maintenance through the prediction of the wear degree of the cryogenics dynamical systems having as variable the monitoring of the lubrication from oiling system of the components with dynamical function. The monitoring wear degrees knowing at a given moment of the dynamical components is determined through the fuzzy method the wear degree of the system formed from monitoring components.
REUs: undergraduate research experiences and funding
Authors: Joan Peckham, Fatma Mili, Daniela Stan Raicu, Ingrid Russell
Venue: Journal of Computing Sciences in Colleges (2008)

Researchers are sometimes daunted by the specter of bringing undergraduate students into their labs without compromising their research agenda, but still providing a meaningful educational experience for students. This panel brings together experienced undergraduate research mentors to discuss and explore the challenges, strategies, and benefits of robust research programs for undergraduates.
Secure and DoS-Resistant Code Dissemination in Wireless Sensor Networks Using Seluge
Authors: An Liu, Young-Hyun Oh, Peng Ning
Venue: Proceedings of the 7th international conference on Information processing in sensor networks (2008)

It is desirable and sometimes necessary to reprogram sensor nodes through wireless links after they are deployed, due to, for example,the need of removing bugs and adding new functionalities. The process of propagating a new code image to the nodes in a network is commonly referred to as code dissemination. In hostile environments, where there may be malicious attacks against wireless sensor networks, code dissemination faces threats from both external attackers and potentially compromised nodes. This demo will show how Seluge, asecure and DoS-resistant code dissemination system based Deluge, worksin wireless sensor networks. Our demo will consist of two parts: (1) ademo in an on-site small-scale network, and (2) a demo in a remote test-bed named WiSeNeT, which is physically deployed in Engineering Building II at North Carolina State University.
PST: a new evolutionary approach to topographic mapping
Authors: Massimo Buscema, Stefano Terzi
Venue: Proceedings of the 7th WSEAS International Conference on Evolutionary Computing (2006)

In this paper we approach the problem of Topographic Mapping. We introduce a new algorithm based on an evolutionary approach with very competitive performances in alternative to some algorithms found in literature. The Pick and Squash algorithm (P.S.T.) is also able to manage incomplete data and it is metric independent.
Positive periodic solutions of second-order nonlinear differential systems with two parameters
Authors: Jun Wu, Zhicheng Wang
Venue: Computers Mathematics with Applications (2008)

By employing the Deimling fixed point index theory, we consider a class of second-order nonlinear differential systems with two parameters (@l,@m)@?R"+^2@?{(0,0)}. We show that there exist three nonempty subsets of R"+^2@?{(0,0)}: @C, @D"1 and @D"2 such that R"+^2@?{(0,0)}=@C@?@D"1@?@D"2 and the system has at least two positive periodic solutions for (@l,@m)@?@D"1, one positive periodic solution for (@l,@m)@?@C and no positive periodic solutions for (@l,@m)@?@D"2. Meanwhile, we find two straight lines L"1 and L"2 such that @C lies between L"1 and L"2.
The influence of the peak location on the additivity of the high dimensional model representation
Authors: Caner Gülpinar, N. Abdulbaki Baykara, Metin Demiralp
Venue: Proceedings of the 12th WSEAS International Conference on Applied Mathematics (2007)

Mathematical modeling of physical systems are commonly faced situations. Solution depends on the quality of the modeling directly. Among the many techniques, High Dimensional Model Representation (HDMR) is a new method that brings great efficiency to the modeling of a system. Although Interpolation, Splines, Finite differences etc. are useful methods, they do not often give as good results as HDMR does. These methods need more reference points or nodes and higher order polynomials for better results, and this means higher cost calculations. However, HDMR offers new expansions, truncation of intended order, needed for less sample points etc.. Since HDMR is a modeling method based on optimization and projection operator theory, solving problems with differential equations, input - output systems require less calculations with high effectiveness. In addition, HDMR contains analysis of variance calculations. Hence, HDMR is also an effective method for statistics.
An Authentication Mechanism of Digital Contents in Pervasive Computing Environment
Authors: Eun-Gyeom Jang, Byoung-Soo Koh, Yong-Rak Choi
Venue: Proceedings of the 2008 International Conference on Information Security and Assurance (isa 2008) (2008)

Digital content services in Pervasive Computing Environment provide a vast range of information and rapidly. However, in this environment where various information flow the copyright infringement problems such as modification and fraudulent use of digital content without permission of copyright holder are increased. In this paper, we proposed an original digital content authentication method to protect the intellectual property from such infringements. The proposed mechanism sets the scope of content usage and limits the access privilege to digital content by copyright holder. The modification of digital content and its usage are act of copyright infringement. That is, modification of color and resolution out of the limited scope and partial modification or extraction are part of copyright infringement. Consequently, we proposed a mechanism which proves the fact of trespass by extracting and comparing the similarity of the original and the target content.
On the randomized complexity of volume and diameter
Authors: L. Lovasz
Venue: Proceedings of the 33rd Annual Symposium on Foundations of Computer Science (1992)

The authors give an O(n/sup 7/log/sup 2/n) randomised algorithm to approximate the volume of a convex body, and an O(n/sup 6/log n) algorithm to sample a point from the uniform distribution over a convex body. For convex polytopes the algorithm runs in O(n/sup 7/log/sup 4/n) steps. Several tools are developed that may be interesting on their own. They extend results of Sinclair-Jerrum (1988) and the authors (1990) on the mixing rate of Markov chains from finite to arbitrary Markov chains. They describe an algorithm to integrate a function with respect to the stationary distribution of a general Markov chain. They also analyze the mixing rate of various random walks on convex bodies, in particular the random walk with steps from the uniform distribution over a unit ball. In several previous positive and negative results, the problem of computing the diameter of a convex body behaved similarly as the volume problem. In contrast to this, they show that there is no polynomial randomized algorithm to compute the diameter within a factor of n/sup 1/4/.
Relevance thresholds in system evaluations
Authors: Falk Scholer, Andrew Turpin
Venue: Proceedings of the 31st annual international ACM SIGIR conference on Research and development in information retrieval (2008)

We introduce and explore the concept of an individual's relevance threshold as a way of reconciling differences in outcomes between batch and user experiments.
The design of natural interaction
Authors: Alessandro Valli
Venue: Multimedia Tools and Applications (2008)

This paper addresses the problem of the relationship between humans and technology-enhanced spaces and physical objects (later defined as artifacts). The class of cases here analyzed includes interactive digital signage, information kiosks, home media centers and interactive spaces whose purpose is the communication of a meaning. In this domain, complex interfaces are not needed, as common people interaction with information, content and media is in most cases extremely simple. The topic of specialized interfaces for expert users is not addressed here; the focus is on interfaces for the general public, whose main purpose is the basic fruition of digital information, although such information can be large and complex in its organization. This paper is centered on the need of conceiving computer sensing and information presentation as different aspects of the same interaction design problem, instead of separate research entities.
Intrusion Detection in Homogeneous and Heterogeneous Wireless Sensor Networks
Authors: Yun Wang, Xiaodong Wang, Bin Xie, Demin Wang, Dharma P. Agrawal
Venue: IEEE Transactions on Mobile Computing (2008)

Intrusion detection in Wireless Sensor Network (WSN) is of practical interest in many applications such as detecting an intruder in a battlefield. The intrusion detection is defined as a mechanism for a WSN to detect the existence of inappropriate, incorrect, or anomalous moving attackers. For this purpose, it is a fundamental issue to characterize the WSN parameters such as node density and sensing range in terms of a desirable detection probability. In this paper, we consider this issue according to two WSN models: homogeneous and heterogeneous WSN. Furthermore, we derive the detection probability by considering two sensing models: single-singing detection and multiple-sensing detection. In addition, we discuss the network connectivity and broadcast reachability, which are necessary conditions to ensure the corresponding detection probability in a WSN. Our simulation results validate the analytical values for both homogeneous and heterogeneous WSNs.
High Output Resistance and Wide Swing Voltage Charge Pump Circuit
Authors: Tian Xia, Stephen Wyatt
Venue: Proceedings of the 9th international symposium on Quality Electronic Design (2008)

This paper presents a new charge pump circuit to minimize the current mismatch. By connecting a common-gate and a common-source amplifier as the feedback voltage regulator, the highly matched charge pump currents are accomplished. Additionally, the proposed circuit has wide output voltage swing, which ensures its good performance under very low power supply.
The economy of collective attention for situated knowledge collaboration in software development
Authors: Yunwen Ye, Kumiyo Nakakoji, Yasuhiro Yamamoto
Venue: Proceedings of the 2008 international workshop on Cooperative and human aspects of software engineering (2008)

Because the knowledge required for the construction of a complex software system is often widely distributed among its members, programmers routinely engage in collaboration with each other to acquire knowledge resided in the heads of their peers to accomplish their own programming tasks. We call this kind of collaboration situated knowledge collaboration. Situated knowledge collaboration comes with costs and the costs vary depending on the communication mechanism used. To understand the cost-benefit structure of different communication mechanisms in support of situated knowledge collaboration, we propose the conceptual framework of collective attention economy. The analytic power of the conceptual framework is illustrated in the comparison of two communication mechanisms.
Strict majority functions on graphs
Authors: Michael A. Henning, Hugh R. Hind
Venue: Journal of Graph Theory (1998)

An opinion function on a graph G = (V, E) is a function f: V ➝ {-1, +1}. The vote of a vertex v is the sum of these function values over the closed neighborhood of v. A strict majority function on a graph G is an opinion function for which more than half of the vertices have a positive vote. The strict majority number of G is the minimum sum of the values in a strict majority function of G. We prove the conjecture of Cockayne and Mynhardt (Ars. Combin. 43 (1996), 235245) that every tree has strict majority number at most 2. We also prove that every graph has strict majority number at most 4. Both bounds are sharp. &copy; 1998 John Wiley Sons, Inc. J Graph Theory 28: 4956, 1998
Explicit stochastic predictive control of combustion plants based on Gaussian process models
Authors: Alexandra Grancharova, Juš Kocijan, Tor A. Johansen
Venue: Automatica (Journal of IFAC) (2008)

Energy production is one of the largest sources of air pollution. A feasible method to reduce the harmful flue gases emissions and to increase the efficiency is to improve the control strategies of the existing thermoelectric power plants. This makes the Nonlinear Model Predictive Control (NMPC) method very suitable for achieving an efficient combustion control. Recently, an explicit approximate approach for stochastic NMPC based on a Gaussian process model was proposed. The benefits of an explicit solution, in addition to the efficient on-line computations, include also verifiability of the implementation, which is an essential issue in safety-critical applications. This paper considers the application of an explicit approximate approach for stochastic NMPC to the design of an explicit reference tracking NMPC controller for a combustion plant based on its Gaussian process model. The controller brings the air factor (respectively the concentration of oxygen in the flue gases) on its optimal value with every change of the load factor and thus an optimal operation of the combustion plant is achieved.
Matching Policies with Security Claims of Mobile Applications
Authors: Nataliia Bielova, Marco Dalla Torre, Nicola Dragoni, Ida Siahaan
Venue: Proceedings of the 2008 Third International Conference on Availability, Reliability and Security (2008)

The Security-by-Contract (SxC) framework has been recently proposed to address the trust relationship problem of the current security model adopted for mobile devices. The key idea of SxC (similar to the one of Model-Carrying Code) is to augment mobile code with a claim on its security behavior (a contract) that could be matched against a mobile platform policy before downloading the code. The rational is that, thanks to SxC, a digital signature does not just certify the origin of the code but also bind together the code with a contract. In this paper we address one of the key issue of the SxC paradigm, namely the contract-policy matching problem, proposing a prototype for matching policies with security claims of mobile applications. This result can be considered a key step towards the achievement of the SxC main goal: provide a semantics for digital signatures on mobile code, thus being a step in the transition from trusted code to trustworthy code.