37 results on '"Volkovich, Zeev"'
Search Results
2. Exploring Compressed Sensing for Proficient Cryptocurrency Mining
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Avros, Renata, Kesselman, Uri, and Volkovich, Zeev
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- 2024
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3. COVID-19 genomes classification using the Deep Impostors approach
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Avros, Renata, Avioz, Kfir, Avioz, On, and Volkovich, Zeev
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- 2023
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4. Deep Sentimental Analysis of the Arabic Medieval Documents
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Avros, Renata and Volkovich, Zeev
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- 2022
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5. A multi-criteria approach to optimization of acoustic feedback detection
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Ravve, Elena V. and Volkovich, Zeev
- Published
- 2021
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6. Application of N-Gram Based Distances to Genetic Texts Comparison
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Kirzhner, Valery and Volkovich, Zeev
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- 2021
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7. Patterning of writing style evolution by means of dynamic similarity
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Amelin, Konstantin, Granichin, Oleg, Kizhaeva, Natalia, and Volkovich, Zeev
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- 2018
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8. Indoor Navigation in Facilities with Repetitive Structures.
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Volkovich, Zeev, Ravve, Elena V., and Avros, Renata
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- *
INDOOR positioning systems , *NAVIGATION , *USER interfaces , *PASSENGER ships - Abstract
Most facilities are structured in a repetitive manner. In this paper, we propose an algorithm and its partial implementation for a cellular guide in such facilities without GPS use. The complete system is based on iBeacons-like components, which operate on BLE technology, and their integration into a navigation application. We assume that the user's location is determined with sufficient accuracy. Our main goal revolves around leveraging the repetitive structure of the given facility to optimize navigation in terms of storage requirements, energy efficiency in the cellular device, algorithmic complexity, and other aspects. To the best of our knowledge, there is no prior experience in addressing this specific aim. In order to provide high performance in real time, we rely on optimal saving and the use of pre-calculated and stored navigation sub-routes. Our implementation seamlessly integrates iBeacon communications, a pre-defined indoor map, diverse data structures for efficient information storage, and a user interface, all working cohesively under a single supervision. Each module can be considered, developed, and improved independently. The approach is mainly directed to places, such as passenger ships, hotels, colleges, and so on. Because of the fact that there are "replicated" parts on different floors, stored once and used for multiple routes, we reduce the amount of information that must be stored, thus helping to reduce memory usage and as a result, yielding a better running time and energy consumption. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Spotting Suspicious Academic Citations Using Self-Learning Graph Transformers.
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Avros, Renata, Haim, Mor Ben, Madar, Almog, Ravve, Elena, and Volkovich, Zeev
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TRANSFORMER models ,AUTODIDACTICISM ,GRAPH connectivity - Abstract
The study introduces a novel approach to identify potential citation manipulation within academic papers. This method utilizes perturbations of a deep embedding model, integrating Graph-Masked Autoencoders to merge textual information with evidence of graph connectivity. Consequently, it yields a more intricate model of citation distribution. By training a deep network with partial data and reconstructing masked connections, the approach capitalizes on the inherent characteristics of central connections amidst network perturbations. It demonstrates its ability to pinpoint trustworthy citations within the analyzed dataset through comprehensive quantitative evaluations. Additionally, it raises concerns regarding the reliability of specific references, which may be subject to manipulation. [ABSTRACT FROM AUTHOR]
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- 2024
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10. Assembly Function Recognition in Embedded Systems as an Optimization Problem.
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Avitan, Matan, Ravve, Elena V., and Volkovich, Zeev
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MATHEMATICAL optimization ,BINARY codes ,COMPUTER software development ,SET functions ,INTEGRATED software ,DEBUGGING - Abstract
Many different aspects of software system development and verification rely on precise function identification in binary code. Recognition of the source Assembly functions in embedded systems is one of the fundamental challenges in binary program analysis. While numerous approaches assume that the functions are given a priori, correct identification of the functions in binaries remains a great issue. This contribution addresses the problem of uncertainty in binary code in identification of functions, which were optimized during compilation. This paper investigates the difference between debug and optimized functions via modeling of these functions. To do so, we introduce an extensible model-centred hands-on approach for examining similarities between binary functions. The main idea is to model each function using a set of predetermined, experimentally discovered features, and then find a suitable weight vector that could give impact factor to each such a feature. After finding the weight vector, the introduced models of such desired functions can be identified in binary software packages. It means that we reduce the similarity identification problem of the models to a classical version of optimization problems with one optimization criterion. Using our implementation, we found that the proposed approach works smoothly for functions, which contain at least ten Assembly instructions. Our tool guarantees success at a very high level. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Literary writing style recognition via a minimal spanning tree-based approach
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Shalymov, Dmitry, Granichin, Oleg, Klebanov, Lev, and Volkovich, Zeev
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- 2016
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12. Modeling and visualization of media in Arabic
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Volkovich, Zeev, Granichin, Oleg, Redkin, Oleg, and Bernikova, Olga
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- 2016
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13. Text Classification Using a Novel Time Series based Methodology
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Volkovich, Zeev and Avros, Renata
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- 2016
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14. An Iterative Projective Clustering Method
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Avros, Renata, Frenkel, Zakharia, Toledano-Kitai, Dvora, and Volkovich, Zeev
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- 2015
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15. Detecting Pseudo-Manipulated Citations in Scientific Literature through Perturbations of the Citation Graph.
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Avros, Renata, Keshet, Saar, Kitai, Dvora Toledano, Vexler, Evgeny, and Volkovich, Zeev
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SCIENTIFIC literature ,STATISTICAL sampling ,TRUST ,SAMPLING (Process) ,STATISTICS - Abstract
Ensuring the integrity of scientific literature is essential for advancing knowledge and research. However, the credibility and trustworthiness of scholarly publications are compromised by manipulated citations. Traditional methods, such as manual inspection and basic statistical analyses, have limitations in detecting intricate patterns and subtle manipulations of citations. In recent years, network-based approaches have emerged as promising techniques for identifying and understanding citation manipulation. This study introduces a novel method to identify potential citation manipulation in academic papers using perturbations of a deep embedding model. The key idea is to reconstruct meaningful connections represented by citations within a network by exploring, to some extent, longer alternative paths. These indirect pathways enable the recovery of reliable citations while estimating their trustworthiness. The investigation takes a comprehensive approach to link prediction, leveraging the consistent behavior of prominent connections when exposed to network perturbations. Through numerical experiments, the method demonstrates a high capability to identify reliable citations as the core of the analyzed data and to raise suspicions about unreliable references that may have been manipulated. This research presents a refined method for tackling the urgent problem of citation manipulation in academic papers. It harnesses statistical sampling and graph-embedding techniques to evaluate the credibility of scholarly publications with a substantial assessment of the whole citation graph. [ABSTRACT FROM AUTHOR]
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- 2023
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16. Robust classifying of prokaryotic genomes
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Korenblat, Katerina, Volkovich, Zeev, and Bolshoy, Alexander
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- 2012
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17. A linguistic approach to classification of bacterial genomes
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Volkovich, Zeev, Kirzhner, Valery, Barzily, Zeev, Hosid, Sergey, and Korenblat, Katerina
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- 2010
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18. Electroencephalography functional connectivity—A biomarker for painful polyneuropathy.
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Topaz, Leah Shafran, Frid, Alex, Granovsky, Yelena, Zubidat, Rabab, Crystal, Shoshana, Buxbaum, Chen, Bosak, Noam, Hadad, Rafi, Domany, Erel, Alon, Tayir, Meir Yalon, Lian, Shor, Merav, Khamaisi, Mogher, Hochberg, Irit, Yarovinsky, Nataliya, Volkovich, Zeev, Bennett, David L., and Yarnitsky, David
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FUNCTIONAL connectivity ,RECEIVER operating characteristic curves ,ELECTROENCEPHALOGRAPHY ,POLYNEUROPATHIES - Abstract
Background and purpose: Advanced analysis of electroencephalography (EEG) data has become an essential tool in brain research. Based solely on resting state EEG signals, a data‐driven, predictive and explanatory approach is presented to discriminate painful from non‐painful diabetic polyneuropathy (DPN) patients. Methods: Three minutes long, 64 electrode resting‐state recordings were obtained from 180 DPN patients. The analysis consisted of a mixture of traditional, explanatory and machine learning analyses. First, the 10 functional bivariate connections best differentiating between painful and non‐painful patients in each EEG band were identified and the relevant receiver operating characteristic was calculated. Later, those connections were correlated with selected clinical parameters. Results: Predictive analysis indicated that theta and beta bands contain most of the information required for discrimination between painful and non‐painful polyneuropathy patients, with area under the receiver operating characteristic curve values of 0.93 for theta and 0.89 for beta bands. Assessing statistical differences between the average magnitude of functional connectivity values and clinical pain parameters revealed that painful DPN patients had significantly higher cortical functional connectivity than non‐painful ones (p = 0.008 for theta and p = 0.001 for alpha bands). Moreover, intra‐band analysis of individual significant functional connections revealed a positive correlation with average reported pain in the previous 3 months in all frequency bands. Conclusions: Resting state EEG functional connectivity can serve as a highly accurate biomarker for the presence or absence of pain in DPN patients. This highlights the importance of the brain, in addition to the peripheral lesions, in generating the clinical pain picture. This tool can probably be extended to other pain syndromes. [ABSTRACT FROM AUTHOR]
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- 2023
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19. Multiple levels of meaning in DNA sequences, and one more
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Trifonov, Edward N., Volkovich, Zeev, and Frenkel, Zakharia M.
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- 2012
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20. Large-scale genome clustering across life based on a linguistic approach
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Kirzhner, Valery, Bolshoy, Alexander, Volkovich, Zeev, Korol, Abraham, and Nevo, Eviatar
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- 2005
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21. Construction of the developing connecting tree.
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Kirzhner, Valery M., Ravve, Elena V., and Volkovich, Zeev
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TREES - Abstract
A problem of linking vertices (objects) by a connecting tree is studied under the condition that objects appear at different given times. In this case, the target function depends not only on the total length of the connecting tree but also on the times of constructing its fragments. This problem is shown to be NP-complete even when the linking is done without intermediate vertices. In this article, some necessary conditions of optimality of the developing connecting tree are formulated. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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22. Evaluating the number of different genomes in a metagenome by means of the compositional spectra approach.
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Kirzhner, Valery, Toledano-Kitai, Dvora, and Volkovich, Zeev
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CLUSTER analysis (Statistics) ,GENOMES ,PATTERN recognition systems ,ALGORITHMS ,METAGENOMICS ,SPECTRUM analysis - Abstract
Determination of metagenome composition is still one of the most interesting problems of bioinformatics. It involves a wide range of mathematical methods, from probabilistic models of combinatorics to cluster analysis and pattern recognition techniques. The successful advance of rapid sequencing methods and fast and precise metagenome analysis will increase the diagnostic value of healthy or pathological human metagenomes. The article presents the theoretical foundations of the algorithm for calculating the number of different genomes in the medium under study. The approach is based on analysis of the compositional spectra of subsequently sequenced samples of the medium. Its essential feature is using random fluctuations in the bacteria number in different samples of the same metagenome. The possibility of effective implementation of the algorithm in the presence of data errors is also discussed. In the work, the algorithm of a metagenome evaluation is described, including the estimation of the genome number and the identification of the genomes with known compositional spectra. It should be emphasized that evaluating the genome number in a metagenome can be always helpful, regardless of the metagenome separation techniques, such as clustering the sequencing results or marker analysis. [ABSTRACT FROM AUTHOR]
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- 2020
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23. Entropy "2"-Soft Classification of Objects.
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Popkov, Yuri S., Volkovich, Zeev, Dubnov, Yuri A., Avros, Renata, and Ravve, Elena
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ENTROPY (Information theory) , *PROBABILITY density function , *LINEAR programming , *COMPUTER simulation , *DISCRIMINANT analysis - Abstract
A proposal for a new method of classification of objects of various nature, named "2"-soft classification, which allows for referring objects to one of two types with optimal entropy probability for available collection of learning data with consideration of additive errors therein. A decision rule of randomized parameters and probability density function (PDF) is formed, which is determined by the solution of the problem of the functional entropy linear programming. A procedure for "2"-soft classification is developed, consisting of the computer simulation of the randomized decision rule with optimal entropy PDF parameters. Examples are provided. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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24. Detecting Non-Uniform Clusters in Large-Scale Interaction Graphs.
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Levtov, Nissan, Amberkar, Sandeep, Frenkel, Zakharia M, Kaderali, Lars, and Volkovich, Zeev
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- 2014
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25. A binomial noised model for cluster validation.
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Toledano-Kitai, Dvora, Avros, Renata, Volkovich, Zeev, Weber, Gerhard-Wilhelm, and Yahalom, Orly
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BINOMIAL theorem ,MATHEMATICAL models ,CLUSTER analysis (Statistics) ,ALGORITHMS ,PROBLEM solving ,PARAMETER estimation ,NUMERICAL analysis ,NEAREST neighbor analysis (Statistics) - Abstract
Cluster validation is the task of estimating the quality of a given partition of a data set into clusters of similar objects. Normally, a clustering algorithm requires a desired number of clusters as a parameter. We consider the cluster validation problem of determining the optimal ('true') number of clusters. We adopt the stability testing approach, according to which, repeated applications of a given clustering algorithm provide similar results when the specified number of clusters is correct. To implement this idea, we draw pairs of independent equal sized samples, where one sample in any pair is drawn from the data source and the other one is drawn from a noised version thereof. We then run the same clustering method on both samples in any pair and test the similarity between the obtained partitions using a general k-Nearest Neighbor Binomial model. These similarity measurements enable us to estimate the correct number of clusters. A series of numerical experiments on both synthetic and real world data demonstrates the high capability of the offered discipline compared to other methods. In particular, the use of a noised data set is shown to produce significantly better results than in the case of using two independent samples which are both drawn from the data source. [ABSTRACT FROM AUTHOR]
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- 2013
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26. On a Minimal Spanning Tree Approach in the Cluster Validation Problem.
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Barzily, Zeev, Volkovich, Zeev, Akteke-Öztürk, Başak, and Weber, Gerhard-Wilhelm
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SPANNING trees , *TREE graphs , *HYPOTHESIS , *NUMERICAL analysis , *GRAPH theory - Abstract
In this paper, a method for the study of cluster stability is purposed. We draw pairs of samples from the data, according to two sampling distributions. The first distribution corresponds to the high density zones of data-elements distribution. Thus it is associated with the clusters cores. The second one, associated with the cluster margins, is related to the low density zones. The samples are clustered and the two obtained partitions are compared. The partitions are considered to be consistent if the obtained clusters are similar. The resemblance is measured by the total number of edges, in the clusters minimal spanning trees, connecting points from different samples. We use the Friedman and Rafsky two sample test statistic. Under the homogeneity hypothesis, this statistic is normally distributed. Thus, it can be expected that the true number of clusters corresponds to the statistic empirical distribution which is closest to normal. Numerical experiments demonstrate the ability of the approach to detect the true number of clusters. [ABSTRACT FROM AUTHOR]
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- 2009
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27. Testing randomness via aperiodic words.
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Rukhin, Andrew L. and Volkovich, Zeev
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STATISTICS , *TRANSCENDENTAL numbers , *IRRATIONAL numbers , *ANALYSIS of covariance , *MATRICES (Mathematics) - Abstract
The properties of statistical procedures based on occurrences of aperiodic patterns in a random text are summarized. Accurate asymptotic formulas for the expected value of the number of aperiodic words occurring a given number of times and for the covariance matrix are given. The form of the optimal linear test based on these statistics is established. These procedures are applied to testing for the randomness of a string of binary digits originating from block ciphers, US government-approved random number generators or classical transcendental numbers. [ABSTRACT FROM AUTHOR]
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- 2008
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28. Multiagent Control of Airplane Wing Stability with "Feathers" under the Flexural Torsional Flutter.
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Shalymov, Dmitry, Granichin, Oleg, Ivanskiy, Yury, and Volkovich, Zeev
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AIRPLANE control systems ,AIRPLANE wings ,FEATHERS ,FLUTTER (Aerodynamics) ,WING-warping (Aerodynamics) ,EVALUATION methodology ,MULTIAGENT systems - Abstract
This paper proposes a novel method for the unbounded oscillation prevention of an aircraft wing under the flexural torsional flutter, an innovative multiagent attitude to control an aircraft wing with a surface consisting of managed rotating "feathers" (agents). Theoretical evaluation of the method demonstrates its high aptitude to avoid an aircraft wing's flexural-torsional vibrations via expansion of the model's ability to dampen the wing oscillations. It potentially allows increasing an aircraft's speed without misgiving of the flutter. A new way to control an aircraft wing based on the Speed-Gradient methodology is suggested to increase the maximal possible flight speed without a flutter occurrence. Provided experiments demonstrate the theoretical advantage of the multiagent approach to the "feathers" rotation control. [ABSTRACT FROM AUTHOR]
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- 2022
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29. Design of ℓ 1 New Suboptimal Fractional Delays Controller for Discrete Non-Minimum Phase System under Unknown-but-Bounded Disturbance.
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Ivanov, Dmitrii, Granichin, Oleg, Pankov, Vikentii, and Volkovich, Zeev
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DIFFERENCE equations ,PATTERN recognition systems ,IMAGE recognition (Computer vision) ,IMAGE processing ,LINEAR equations ,LINEAR matrix inequalities - Abstract
ℓ 1 -regularization methodologies have appeared recently in many pattern recognition and image processing tasks frequently connected to ℓ 1 -optimization in the control theory. We consider the problem of optimal stabilizing controller synthesis for a discrete non-minimum phase dynamic plant described by a linear difference equation with an additive unknown-but-bounded noise. Under considering the "worst" case of noise, the solving of these optimization problem has a combinatorial complexity. The choosing of an appropriate sufficiently high sampling rate allows to achieve an arbitrarily small level of suboptimality using a noncombinatorial algorithm. In this paper, we suggest to use fractional delays to achieve a small level of suboptimality without increasing the sampling rate so much. We propose an approximation of the fractional lag with a combination of rounding and a first-order fractional lag filter. The suggested approximation of the fractional delay is illustrated via a simulation example with a non-minimum phase second-order plant. The proposed methodology appears to be suitable to be used in various pattern recognition approaches. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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30. Emergent Intelligence via Self-Organization in a Group of Robotic Devices.
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Amelin, Konstantin, Granichin, Oleg, Sergeenko, Anna, and Volkovich, Zeev V.
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ARTIFICIAL intelligence ,COMPUTER science ,MULTIAGENT systems ,SWARM intelligence ,LOCAL mass media - Abstract
Networked systems control is a known problem complicated because of the need to work with large groups of elementary agents. In many applications, it is impossible (or difficult) to validate agent movement models and provide sufficiently reliable control actions at the elementary system components level. The evolution of agent subgroups (clusters) leads to additional uncertainty in the studied control systems. We focus on new decentralized control methods based on local communications in complex multiagent dynamical systems. The problem of intelligence in a complex world is considered in connection to multiagent network systems, including a system named airplane with feathers, load balancing, and the multisensor-multitarget tracking problem. Moreover, the new result concerning the emergency of intelligence in a group of robots is provided. All these methods follow the paradigm of the direct reaction of each element (agent) of the system to its sensory data of current situation observations and the corresponding data from a limited number of its neighbors (local communications). At the same time, these algorithms achieve a mutual goal at the macro level. All of the considered emergent intelligence appearances inspire the necessity to "rethink" the previously recognized concepts of computability and algorithm in computer science. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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31. Web Traffic Time Series Forecasting Using LSTM Neural Networks with Distributed Asynchronous Training.
- Author
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Casado-Vara, Roberto, Martin del Rey, Angel, Pérez-Palau, Daniel, de-la-Fuente-Valentín, Luis, Corchado, Juan M., Volkovich, Zeev, Granichin, Oleg, Toledano-Kitai, Dvora, and Crippa, Paolo
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INTERNET traffic ,TIME series analysis ,FORECASTING ,TRAFFIC estimation ,DEMAND forecasting ,WEB services ,RECURRENT neural networks - Abstract
Evaluating web traffic on a web server is highly critical for web service providers since, without a proper demand forecast, customers could have lengthy waiting times and abandon that website. However, this is a challenging task since it requires making reliable predictions based on the arbitrary nature of human behavior. We introduce an architecture that collects source data and in a supervised way performs the forecasting of the time series of the page views. Based on the Wikipedia page views dataset proposed in a competition by Kaggle in 2017, we created an updated version of it for the years 2018–2020. This dataset is processed and the features and hidden patterns in data are obtained for later designing an advanced version of a recurrent neural network called Long Short-Term Memory. This AI model is distributed training, according to the paradigm called data parallelism and using the Downpour training strategy. Predictions made for the seven dominant languages in the dataset are accurate with loss function and measurement error in reasonable ranges. Despite the fact that the analyzed time series have fairly bad patterns of seasonality and trend, the predictions have been quite good, evidencing that an analysis of the hidden patterns and the features extraction before the design of the AI model enhances the model accuracy. In addition, the improvement of the accuracy of the model with the distributed training is remarkable. Since the task of predicting web traffic in as precise quantities as possible requires large datasets, we designed a forecasting system to be accurate despite having limited data in the dataset. We tested the proposed model on the new Wikipedia page views dataset we created and obtained a highly accurate prediction; actually, the mean absolute error of predictions regarding the original one on average is below 30. This represents a significant step forward in the field of time series prediction for web traffic forecasting. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
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32. Cluster Flows and Multiagent Technology.
- Author
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Granichin, Oleg, Uzhva, Denis, and Volkovich, Zeev
- Subjects
GOAL (Psychology) ,INTERNAL auditing ,DYNAMICAL systems ,NONLINEAR systems - Abstract
Multiagent technologies provide a new way for studying and controlling complex systems. Local interactions between agents often lead to group synchronization, also known as clusterization (or clustering), which is usually a more rapid process in comparison with relatively slow changes in external environment. Usually, the goal of system control is defined by the behavior of a system on long time intervals. As is well known, a clustering procedure is generally much faster than the process of changing in the surrounding (system) environment. In this case, as a rule, the control objectives are determined by the behavior of the system at large time intervals. If the considered time interval is much larger than the time during which the clusters are formed, then the formed clusters can be considered to be "new variables" in the "slow" time model. Such variables are called "mesoscopic" because their scale is between the level of the entire system (macro-level) and the level of individual agents (micro-level). Detailed models of complex systems that consist of a large number of elementary components (miniature agents) are very difficult to control due to technological barriers and the colossal complexity of tasks due to their enormous dimension. At the level of elementary components of systems, in many applications it is impossible to verify the models of the agent dynamics with the traditionally high degree of accuracy, due to their miniaturization and high frequency of control actions. The use of new mesoscopic variables can make it possible to synthesize fewer different control inputs than when considering the system as a collection of a large number of agents, since such inputs will be common for entire clusters. In order to implement this idea, the "clusters flow" framework was formalized and used to analyze the Kuramoto model as an attracting example of a complex nonlinear networked system with the effects of opportunities for the emergence of clusters. It is shown that clustering leads to a sparse representation of the dynamic trajectories of the system, which makes it possible to apply the method of compressive sensing in order to obtain the dynamic characteristics of the formed clusters. The essence of the method is as follows. With the dimension N of the total state space of the entire system and the a priori assignment of the upper bound for the number of clusters s, only m integral randomized observations of the general state vector of the entire large system are formed, where m is proportional to the number s that is multiplied by logarithm N / s . A two-stage observation algorithm is proposed: first, the state space is limited and discretized, and compression then occurs directly, according to which reconstruction is then performed, which makes it possible to obtain the integral characteristics of the clusters. Based on these obtained characteristics, further, it is possible to synthesize mesocontrols for each cluster while using general model predictive control methods in a space of dimension no more than s for a given control goal, while taking the constraints obtained on the controls into account. In the current work, we focus on a centralized strategy of observations, leaving possible decentralized approaches for the future research. The performance of the new framework is illustrated with examples of simulation modeling. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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33. A Short-Patterning of the Texts Attributed to Al Ghazali: A "Twitter Look" at the Problem.
- Author
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Volkovich, Zeev
- Subjects
- *
CONVOLUTIONAL neural networks , *ATTRIBUTION of authorship , *SIGNAL processing - Abstract
This article presents an novel approach inspired by the modern exploration of short texts' patterning to creations prescribed to the outstanding Islamic jurist, theologian, and mystical thinker Abu Hamid Al Ghazali. We treat the task with the general authorship attribution problematics and employ a Convolutional Neural Network (CNN), intended in combination with a balancing procedure to recognize short, concise templates in manuscripts. The proposed system suggests new attitudes make it possible to investigate medieval Arabic documents from a novel computational perspective. An evaluation of the results on a previously tagged collection of books ascribed to Al Ghazali demonstrates the method's high reliability in recognizing the source authorship. Evaluations of two famous manuscripts, Mishakat al-Anwa and Tahafut al-Falasifa, questioningly attributed to Al Ghazali or co-authored by him, exhibit a significant difference in their overall stylistic style with one inherently assigned to Al Ghazali. This fact can serve as a substantial formal argument in the long-standing dispute about these manuscripts' authorship. The proposed methodology suggests a new look on the perusal of medieval documents' inner structures and possible authorship from the short-patterning and signal processing perspectives. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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34. Statistical Indicators of the Scientific Publications Importance: A Stochastic Model and Critical Look †.
- Author
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Klebanov, Lev B., Kuvaeva, Yulia V., and Volkovich, Zeev E.
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H-index (Citation analysis) ,STOCHASTIC models ,GEOMETRIC distribution ,SCIENTIFIC models ,DATA analysis ,STOCHASTIC processes - Abstract
A model of scientific citation distribution is given. We apply it to understand the role of the Hirsch index as an indicator of scientific publication importance in Mathematics and some related fields. The proposed model is based on a generalization of such well-known distributions as geometric and Sibuya laws. Real data analysis of the Hirsch index and corresponding citation numbers is given. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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- View/download PDF
35. Entropy-Based Approach for the Detection of Changes in Arabic Newspapers' Content.
- Author
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Bernikova, Olga, Granichin, Oleg, Lemberg, Dan, Redkin, Oleg, and Volkovich, Zeev
- Subjects
ARAB Spring Uprisings, 2010-2012 ,NEWSPAPER publishing ,NEWSPAPERS ,CURRENT distribution ,TIME series analysis ,MAGNETIC entropy - Abstract
A new method for the recognition of meaningful changes in social state based on transformations of the linguistic content in Arabic newspapers is suggested. The detected alterations of the linguistic material in Arabic newspapers play an indicator role. The currently proposed approach acts in an "online" fashion and uses pre-trained vector representations of Arabic words. After a pre-processing stage, the words in the issues' texts are substituted by vectors obtained within a word embedding methodology. The approach typifies the consistent linguistic template by the similarity of the embedded vectors. A change in the distributions of the issue-grounded samples indicates a difference in the underlying newspaper template. A two-step procedure implements the concept, where the first step compares the similarity distribution of the current issue versus the union of ones corresponding to several of its predecessors. A repeating under-sampling approach accompanied by a two-sample test stabilizes the sampling and returns a collection of the resultant p-values. In the second stage, the entropy of these sets is sequentially calculated, such that the change points of the time series obtained in this way indicate the changes in the newspaper content. Numerical experiments provided on the following issues of several Arabic newspapers published in the Arab Spring period demonstrate the high reliability of the method. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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- View/download PDF
36. Hidden ancient repeats in DNA: Mapping and quantification.
- Author
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Frenkel, Zakharia M., Barzily, Zeev, Volkovich, Zeev, and Trifonov, Edward N.
- Subjects
- *
TRINUCLEOTIDE repeats , *GENETIC code , *TANDEM repeats , *BACTERIAL genetics , *ESCHERICHIA coli , *SACCHAROMYCES cerevisiae , *ASCII (Character set) - Abstract
Abstract: We have shown, in a previous paper, that tandem repeating sequences, especially triplet repeats, play a very important role in gene evolution. This result led to the formulation of the following hypothesis: most of the genomic sequences evolved through everlasting acts of tandem repeat expansions with subsequent accumulation of changes. In order to estimate how much of the observed sequences have the repeat origin we describe the adaptation of a text segmentation algorithm, based on dynamic programming, to the mapping of the ancient expansion events. The algorithm maximizes the segmentation cost, calculated as the similarity of obtained fragments to the putative repeat sequence. In the first application of the algorithm to segmentations of genomic sequences, a significant difference between the natural sequences and the corresponding shuffled sequences is detected. The natural fragments are longer and more similar to the putative repeat sequences. As our analysis shows, the coding sequences allow for repeats only when the size of the repeated words is divisible by three. In contrast, in the non-coding sequences, all repeated word sizes are present. It was estimated, that in Escherichia coli K12 genome, about 35.5% of sequence can be detectably traced to original simple repeat ancestors. The results shed light on the genomic sequence organization, and strongly confirm the hypothesis about the crucial role of triplet expansions in gene origin and evolution. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
37. Nucleosome positioning patterns derived from human apoptotic nucleosomes.
- Author
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Frenkel ZM, Trifonov EN, Volkovich Z, and Bettecken T
- Subjects
- Amino Acid Motifs, Base Composition, Base Sequence, Chromatin Assembly and Disassembly, DNA chemistry, Humans, Nucleic Acid Conformation, Apoptosis, Nucleosomes chemistry, Nucleosomes metabolism
- Abstract
This communication reports on the nucleosome positioning patterns (bendability matrices) for the human genome, derived from over 8_million nucleosome DNA sequences obtained from apoptotically digested lymphocytes. This digestion procedure is used here for the first time for the purpose of extraction and sequencing of the nucleosome DNA fragments. The dominant motifs suggested by the matrices of DNA bendability calculated for light and heavy isochores are significantly different. Both, however, are in full agreement with the linear description YRRRRRYYYYYR, and with earlier derivations by N-gram extensions. Thus, the choice of the nucleosome positioning patterns crucially depends on the G + C composition of the analyzed sequences.
- Published
- 2011
- Full Text
- View/download PDF
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