ppxscal/embedding_network huggingface dataset:
A review of physiological simulation models of intracranial pressure dynamics
Authors: Wayne Wakeland, Brahm Goldstein
Venue: Computers in Biology and Medicine (2008)

This paper reviews the literature regarding the development, testing, and application of physiology-based computer simulation models of intracranial pressure dynamics. Detailed comparative information is provided in tabular format about the model variables and logic, any data collected, model testing and validation methods, and model results. Several syntheses are given that summarize the research carried out by influential research teams and researchers, review important findings, and discuss the methods employed, limitations, and opportunities for further research.
Adaptive Optimization of Hospital Resource Calendars
Authors: I. B. Vermeulen, S. M. Bohte, S. G. Elkhuizen, J. S. Lameris, P. J. Bakker, J. A. Poutré
Venue: Proceedings of the 11th conference on Artificial Intelligence in Medicine (2007)

As demand for health care increases, a high efficiency on limited resources is necessary for affordable high patient service levels. Here, we present an adaptive approach to efficient resource usage by automatic optimization of resource calendars. We describe a precise model based on a case study at the radiology department of the Academic Medical Center Amsterdam (AMC). We model the properties of the different groups of patients, with additional differentiating urgency levels. Based on this model, we develop a detailed simulation that is able to replicate the known scheduling problems. In particular, the simulation shows that due to fluctuations in demand, the allocations in the resource calendar must be flexible in order to make efficient use of the resources. We develop adaptive algorithms to automate iterative adjustments to the resource calendar. To test the effectiveness of our approach, we evaluate the algorithms using the simulation. Our adaptive optimization approach is able to maintain overall target performance levels while the resource is used at high efficiency.
Three-Phase Inverse Design Stefan Problem
Authors: Damian Słota
Venue: Proceedings of the 7th international conference on Computational Science, Part I: ICCS 2007 (2007)

The method of the convective heat transfer coefficient identification in a three-phase inverse design Stefan problem is presented in this paper. The convective heat transfer coefficient will be sought in the form of a continuous function, non-linearly dependent on the parameters sought. A genetic algorithm was used to determine these parameters. The direct Stefan problem was solved via a generalized alternating phase truncation method. Stability of the whole algorithm was ensured by applying the Tikhonov regularization technique.
Analysis on Spatio-temporal Characteristics of Wintertime Planetary Wave in the Northern Hemisphere Based on 2D FFT
Authors: Xiuhong Wang, Weidong Yu
Venue: Proceedings of the 7th international conference on Computational Science, Part III: ICCS 2007 (2007)

To describe spatial and temporal characteristics of the activities of wintertime planetary waves in the northern hemisphere, their numbers and periods were precisely calculated, based on NCAR/NCEP reanalysis data. The objective variables include sea level pressure (SLP) and anomaly stream function at 850 hPa, 500 hPa and 200 hPa. 2D FFT and spectral analysis reveal that: (1) The wave numbers 1 and 2 dominate the perturbation pattern at 70°-80°N zonal belt. (2) The wave numbers 1, 2 and 3 dominate at 60°-70°N zonal belt. (3) The wave numbers 1-4 dominate at 50°-60°N zonal belt. The results accord fairly well with Rossby's classical trough formula and are of potential use for understanding the northern hemisphere large-scale oscillations.
Methods for Increasing Coverage in Wireless Sensor Networks
Authors: Sunggu Lee, Younggyu Yang
Venue: Proceedings of the 6th IFIP WG 10.2 international workshop on Software Technologies for Embedded and Ubiquitous Systems (2008)

In a Wireless Sensor Network, it is important to be able to maintain a sufficient level of coverage for a given target area. This paper addresses the problem of determining how many and where to place additional sensor nodes in order to increase the coverage from k to k + 1. Several possible candidate solution methods for this problem are proposed and evaluated using theoretical and simulation-based analysis.
Multilogistic regression by means of evolutionary product-unit neural networks
Authors: C. Hervás-Martínez, F. J. Martínez-Estudillo, M. Carbonero-Ruz
Venue: Neural Networks (2008)

We propose a multilogistic regression model based on the combination of linear and product-unit models, where the product-unit nonlinear functions are constructed with the product of the inputs raised to arbitrary powers. The estimation of the coefficients of the model is carried out in two phases. First, the number of product-unit basis functions and the exponents' vector are determined by means of an evolutionary neural network algorithm. Afterwards, a standard maximum likelihood optimization method determines the rest of the coefficients in the new space given by the initial variables and the product-unit basis functions previously estimated. We compare the performance of our approach with the logistic regression built on the initial variables and several learning classification techniques. The statistical test carried out on twelve benchmark datasets shows that the proposed model is competitive in terms of the accuracy of the classifier.
Hybrid Force and Position Control of Robotic Manipulators Using Passivity Backstepping Neural Networks
Authors: Shu-Huan Wen, Bing-Yi Mao
Venue: Proceedings of the 4th international symposium on Neural Networks: Advances in Neural Networks (2007)

This paper presents a method of force/position control by using the backstepping and passivity strict-feedback neural networks technique; passivity monitor can evaluate stability of a system based on the concept of passivity. The parameters estimation for the design is made by the neural networks technology, using the decouple method and matrix transforming technology, decomposing the robot system as the position subsystem and the force subsystem, then the control law of these subsystems are designed respectively. The results obtained are satisfactory by using hybrid force and position control, the error is negligible and the global stability of the system can also be obtained.
A characterization of flip-accessibility for rhombus tilings of the whole plane
Authors: Olivier Bodini, Thomas Fernique, Éric Rémila
Venue: Information and Computation (2008)

It is known that any two rhombus tilings of a polygon are flip-accessible, that is, linked by a finite sequence of local transformations called flips. This paper considers flip-accessibility for rhombus tilings of the whole plane, asking whether any two of them are linked by a possibly infinite sequence of flips. The answer turning out to depend on tilings, a characterization of flip-accessibility is provided. This yields, for example, that any tiling by Penrose tiles is flip-accessible from a Penrose tiling.
Combining Trust and Reputation Management for Web-Based Services
Authors: Audun Jøsang, Touhid Bhuiyan, Yue Xu, Clive Cox
Venue: Proceedings of the 5th international conference on Trust, Privacy and Security in Digital Business (2008)

Services offered and provided through the Web have varying quality, and it is often difficult to assess the quality of a services before accessing and using it. Trust and reputation systems can be used in order to assist users in predicting and selecting the best quality services. This paper describes how Bayesian reputation systems can be combined with trust modeling based on subjective logic to provide an integrated method for assessing the quality of online services. This will not only assist the user's decision making, but will also provide an incentive for service providers to maintain high quality, and can be used as a sanctioning mechanism to discourage deceptive and low quality services.
On the Computation of Elimination Ideals of Boolean Polynomial Rings
Authors: Yosuke Sato, Akira Nagai, Shutaro Inoue
Venue: Computer Mathematics: 8th Asian Symposium, ASCM 2007, Singapore, December 15-17, 2007. Revised and Invited Papers (2008)

In order to compute an eliminate portion of a given polynomial ideal by a Gröbner basis computation, we usually need to compute a Gröbner basis of the whole ideal with respect to some proper term order. In a boolean polynomial ring, we show that we can compute an eliminate portion by computing Gröbner bases in the boolean polynomial ring with the same coefficient ring that has the only variables which we want to eliminate. We also check the efficiency of our method through our implementation.
Constitutive Modelling of Endothelium Denudation for Finite Element Simulation of Angioplasty
Authors: Sébastien Delorme, Rouwayda El-Ayoubi, Patricia Debergue
Venue: Proceedings of the 4th international symposium on Biomedical Simulation (2008)

This study aims at characterizing and modelling the effect of mechanical factors on endothelial denudation during angioplasty, such as normal force between balloon and artery, stretching of arterial walls, and relative displacement between contacting surfaces. Friction damage was applied to porcine aorta samples with different contact forces, relative displacements, and biplanar stretching conditions. After the tests, endothelium denudation was quantified by isolating and counting the remaining endothelial cells. Using multiple-regression analysis, a constitutive model is proposed for integration in finite element software. This model will help optimize balloon and stent deployment conditions to minimize the amount of damage to the endothelium, and eventually to reduce the occurrence of restenosis.
A new method of oxide charges densities determination using charge-pumping technique in MOS structures
Authors: Hamid Bentarzi, Abdelkader Zitouni, Youcef Kribes
Venue: Proceedings of the 7th WSEAS International Conference on Microelectronics, Nanoelectronics, Optoelectronics (2008)

A Novel electrical method, using charge-pumping (CP) technique under bias thermal stress (BTS), has been described in this work. This technique is based on the measurement of the flat-band voltage before and after an applied voltage at high temperature through the use of charge-pumping current. The measured flat band shift, that may be due to effect of certain types of the oxide charges, may be used to detect these types of oxide charges and to determine their densities.
Supervised Gravitational Clustering with Bipolar Fuzzification
Authors: Umut Orhan, Mahmut Hekim, Turgay Ibrikci
Venue: Proceedings of the 4th international conference on Intelligent Computing: Advanced Intelligent Computing Theories and Applications - with Aspects of Artificial Intelligence (2008)

Data clustering is an important part of cluster analysis. Numerous semi-supervised or supervised clustering algorithms based on various theories have been developed, and new clustering algorithms continue to appear in the literature. The problem of common supervised clustering is to train a clustering algorithm to produce desirable clusters and complete clusters over datasets and learn how to cluster future sets of objects. In this paper, we have proposed an algorithm called Supervised Gravitational Clustering based on bipolar fuzzification. Traditional supervised clustering methods identify class-uniform clusters; but the offered method identifies class-multiform clusters with high probability densities. For this aim we have proposed two approaches: common effect and maximal effect. The first, common effect approach, calculates total effect of all class-centers over searching point. Also, this approach is basis for mapping of novel method. The second, maximal effect approach, determines class-centers with the strongest effect over searching point.
Tensor Space Models for Authorship Identification
Authors: Spyridon Plakias, Efstathios Stamatatos
Venue: Proceedings of the 5th Hellenic conference on Artificial Intelligence: Theories, Models and Applications (2008)

Authorship identification can be viewed as a text categorization task. However, in this task the most frequent features appear to be the most important discriminators, there is usually a shortage of training texts, and the training texts are rarely evenly distributed over the authors. To cope with these problems, we propose tensors of second order for representing the stylistic properties of texts. Our approach requires the calculation of much fewer parameters in comparison to the traditional vector space representation. We examine various methods for building appropriate tensors taking into account that similar features should be placed in the same neighborhood. Based on an existing generalization of SVM able to handle tensors we perform experiments on corpora controlled for genre and topic and show that the proposed approach can effectively handle cases where only limited training texts are available.
Watermarking, steganography and content forensics
Authors: Ingemar J. Cox
Venue: Proceedings of the 10th ACM workshop on Multimedia and security (2008)

Electronic watermarking is about 60 years old. However it was not until the beginning of the early 1990's that watermarking received widespread interest, due to concerns about piracy of digital content. In the subsequent decade, very significant progress has been made both in our theoretical understanding of digital watermarking and in its applications. In this talk we highlight some of the progress made and describe a number of current and possible watermarking applications. Steganography has a much longer history, dating back to at least the time of the ancient Greeks. While Shannon dismissed steganography as "primarily a psychological problem", the last decade has seen the application of information theory to steganography. Terrorist events at the beginning of the 21st century motivated further attention and very interesting results have been described. At first sight, digital watermarking and steganography would appear to share the same goals. However, while both seek to hide information within other information or content, there are very significant differences in the constraints that must be satisfied. For example, in digital watermarking being imperceptible is very important. However, in steganography being imperceptible is less important than being undetectable, since the original cover Work is not available for comparison. The similarities and differences between digital watermarking and steganography are highlighted here. Steganography spawns steganalysis, the art and science of detecting the presence of a steganographic message hidden in innocuous content. Recent research views steganalysis as a binary classification problem; is a hidden message present or absent? Classification is based on testing for statistical anomalies in features derived from the content. We will describe a variety of steganalysis algorithms, and discuss approaches to evaluating and benchmarking these algorithms. Content forensics shares similarities with steganalysis. At the simplest level, content forensics is often asked whether, for example, an image is authentic or has been tampered with. This problem can also be viewed as a binary classification problem and similar techniques can be applied. We will review recent work in content forensics and discuss their current limitations.
The Geometry of the Neighbor-Joining Algorithm for Small Trees
Authors: Kord Eickmeyer, Ruriko Yoshida
Venue: Proceedings of the 3rd international conference on Algebraic Biology (2008)

In 2007, Eickmeyer et al. showed that the tree topologies outputted by the Neighbor-Joining (NJ) algorithm and the balanced minimum evolution (BME) method for phylogenetic reconstruction are each determined by a polyhedral subdivision of the space of dissimilarity maps ${\mathbb R}^{n \choose 2}$, where n is the number of taxa. In this paper, we will analyze the behavior of the Neighbor-Joining algorithm on five and six taxa and study the geometry and combinatorics of the polyhedral subdivision of the space of dissimilarity maps for six taxa as well as hyperplane representations of each polyhedral subdivision. We also study simulations for one of the questions stated by Eickmeyer et al., that is, the robustness of the NJ algorithm to small perturbations of tree metrics, with tree models which are known to be hard to be reconstructed via the NJ algorithm.
Three-Dimensional Anisotropic Noise Reduction with Automated Parameter Tuning: Application to Electron Cryotomography
Authors: J. J. Fernández, S. Li, V. Lucic
Venue: Current Topics in Artificial Intelligence: 12th Conference of the Spanish Association for Artificial Intelligence, CAEPIA 2007, Salamanca, Spain, November 12-16, 2007. Selected Papers (2007)

This article presents an approach for noise filtering that is based on anisotropic nonlinear diffusion. The method combines edge-preserving noise reduction with a strategy to enhance local structures and a mechanism to further smooth the background. We have provided the method with an automatic mechanism for parameter self-tuning and for stopping the iterative filtering process. The performance of the approach is illustrated with its application to electron cryotomography (cryoET). CryoET has emerged as a leading imaging technique for visualizing the molecular architecture of complex biological specimens. A challenging computational task in this discipline is to increase the extremely low signal-to-noise ratio (SNR) to allow visualization and interpretation of the three-dimensional structures. The filtering method here proposed succeeds in substantially reducing the noise with excellent preservation of the structures.
Brain Organization and Computation
Authors: Andreas Schierwagen
Venue: Proceedings of the 2nd international work-conference on The Interplay Between Natural and Artificial Computation, Part I: Bio-inspired Modeling of Cognitive Tasks (2007)

Theories of how the brain computes can be differentiated in three general conceptions: the algorithmic approach, the neural information processing (neurocomputational) approach and the dynamical systems approach. The discussion of key features of brain organization (i.e. structure with function) demonstrates the self-organizing character of brain processes at the various spatio-temporal scales. It is argued that the features associated with the brain are in support of its description in terms of dynamical systems theory, and of a concept of computation to be developed further within this framework.
A Secure Routing Protocol for Wireless Embedded Networks
Authors: Cheng-Fu Liao, Yung-Feng Lu, Ai-Chun Pang, Tei-Wei Kuo
Venue: Proceedings of the 2008 14th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications (2008)

This paper presents a power-aware secure routing protocol for wireless embedded networks (WENs). We propose an efficient secure relay scheme called ESRS for ad-hoc-based embedded-network communications. ESRS is a two-phase scheme which includes end-to-end secure channel establishment and relay-behavior monitoring. With end-to-end secure channel establishment, the transmitted data will be protected under an end-to-end secure channel. A power-aware secure route will be also provided in this stage. Then attacks of routing are monitored and controlled in the monitoring phase. As the experimental results are shown, ESRS provides an efficient way to relay data securely for ad-hoc-based embedded network communications.
Multimedia Adaptation Decisions Modelled as Non-deterministic Operations
Authors: Fernando López, Dietmar Jannach, José M. Martínez, Christian Timmerer, Hermann Hellwagner, Narciso García
Venue: Proceedings of the 2008 Ninth International Workshop on Image Analysis for Multimedia Interactive Services (2008)

This paper describes how a multimedia adaptation framework can automatically decide the sequence of operations to be executed in order to adapt an MPEG-21 Digital Item to the MPEG-21 description of the usage environment in which it will be consumed. The main innovation of this work with respect to previous multimedia adaptation decision models is that in the proposed approach decisions can be made without knowing the exact behaviour of the operations that are going to be executed.
Cryptography Adapted to the New European Area of Higher Education
Authors: A. Queiruga Dios, L. Hernández Encinas, D. Queiruga
Venue: Proceedings of the 8th international conference on Computational Science, Part II (2008)

A new experience for teaching Cryptography to engineering students is shown. The aim is to give them a better understanding of secure and cryptographic algorithms by using Maple software, in a graduate-level course. In this paper we discuss how to structure, define, and implement a web-based course as a part of the traditional classes, according to the convergence of the European Higher Education Project. The proposed course facilitates the use of new Information and Communication Technologies.
What Might "Understand a Function" Mean?
Authors: James H. Davenport
Venue: Proceedings of the 14th symposium on Towards Mechanized Mathematical Assistants: 6th International Conference (2007)

Many functions in classical mathematics are largely defined in terms of their derivatives, so Bessel's function is "the" solution of Bessel's equation, etc. For definiteness, we need to add other properties, such as initial values, branch cuts, etc. What actually makes up "the definition" of a function in computer algebra? The answer turns out to be a combination of arithmetic and analytic properties.
Analysis of dynamic traffic grooming in realistic scenarios
Authors: Zoltán Zsóka, Balázs Farkas
Venue: Proceedings of the 1st international conference on Simulation tools and techniques for communications, networks and systems & workshops (2008)

IP over Optical networks are emerging as one of the future architectures to support the growth of the Internet by simplifying the the network structure and layering. Many evaluation works on these architectures, however, simply neglect the possible effects of a real network environment. In this paper we compare some overlay dynamic grooming algorithms in realistic scenarios from both the topology and traffic pattern point of view. As reference we present results where IP traffic is considered as constant bitrate sessions and highlight the differences between the models. Results show that the traffic model, scenario, and topology may have a larger effect than expected in grooming algorithms, specially when dynamic, reactive protocols are deployed.
Optimal sliding-mode control scheme for the position tracking servo control system
Authors: Jiang Jing
Venue: Proceedings of the 8th WSEAS International Conference on Robotics, Control and Manufacturing Technology (2008)

A new design approach of an optimal sliding-mode variable structure controller with integral compensation is presented for the position tracking servo control system in this paper. The method for obtaining switching function, integral gain and control function is also given. It can achieve accurate servo tracking in the presence of the disturbance and the plant parameter variation. Simulation results show that the new control algorithm exhibits the better control performance than the classical control method, and the rapidness and robustness of the system are improved. Moreover, its realization is simple and convenient.