ppxscal/embedding_network huggingface dataset:
Cv-nics: a lightweight solution to the correspondence problem
Authors: Randy K. Smith
Venue:  (2009)

In this dissertation, I present a novel approach for solving the correspondence problem using basic statistical classification techniques. While metrics such as Pearson's &rho; or cosine similarity would not be powerful enough to solve the correspondence problem directly, their performance can be enhanced by augmenting the scene with random color static via a projector. Over time, this noise increases the statistical independence of imaged points not in correspondence. This allows the reduction of the correspondence problem to a simple similarity search of temporal features. Extensive experiments have shown the approach to be as effective as more complex structured light techniques at producing very dense correspondence data for a variety of scenes. The approach differentiates itself from traditional structured lighting by not relying on known camera or projector geometries, and by allowing relatively lax capturing conditions. Due to the statistically oriented nature of the approach and unlike more recognition focused techniques, the approach is naturally amenable to quality assessment and analysis. This dissertation provides a background on the correspodence problem, presents empirical and analytical results regarding the new techinque, and reviews the related work in the literature. 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
Technical communique: Forced consensus in networks of double integrator systems with delayed input
Authors: Bo Yang, Huajing Fang
Venue: Automatica (Journal of IFAC) (2010)

This communique presents forced second-order consensus protocols with communication time-delays for the network of agents with double integrator dynamics and gives a measure of the robustness of the protocols to the communication time-delays. By employing a frequency domain method, it is proven that the forced consensus is achieved asymptotically for appropriate time-delay if the network is connected. Particularly, the maximum fixed time-delay that can be tolerated by the network is found. The forced consensus protocols are distributed in the sense that each agent only needs information from its neighboring agents, which reduces the complexity of connections between agents significantly. Numerical simulation results are provided to demonstrate the effectiveness and the sharpness of the theoretical results.
Improved trust-aware recommender system using small-worldness of trust networks
Authors: Weiwei Yuan, Donghai Guan, Young-Koo Lee, Sungyoung Lee, Sung Jin Hur
Venue: Knowledge-Based Systems (2010)

The trust network is a social network where nodes are inter-linked by their trust relations. It has been widely used in various applications, however, little is known about its structure due to its highly dynamic nature. Based on five trust networks obtained from the real online sites, we contribute to verify that the trust network is the small-world network: the nodes are highly clustered, while the distance between two randomly selected nodes is short. This has considerable implications on using the trust network in the trust-aware applications. We choose the trust-aware recommender system as an example of such applications and demonstrate its advantages by making use of our verified small-world nature of the trust network.
Modeling and simulation competency center for mature enterprises
Authors: Jorge Cordeiro Duarte, Mamede Lima-Marques
Venue: Proceedings of the International Workshop on Enterprises & Organizational Modeling and Simulation (2009)

Modeling and simulation (M&S) play a significant role in management and decision making in modern enterprises. New methods, techniques and tools have been arising to help organizations to succeed in M&S. We can find many cases of successfully application of M&S in organizations, but normally departmental efforts. Mature enterprises must have M&S managed and optimized efforts in all their departments. Enterprise wide M&S efforts are challenging and few enterprises succeed on it. This challenge is little explored in literature. Enterprise wide M&S is a complex and multidisciplinary effort and need an integrated view. This paper explores M&S enterprise wide efforts. It offers an integrated approach that links technical and behavioral aspects. It also recommends an enterprise competence center in order to organize and drive the modeling and simulation efforts.
Energy efficient all-to-all broadcast in all-wireless networks
Authors: Doina Bein, S. Q. Zheng
Venue: Information Sciences: an International Journal (2010)

All-to-all broadcast is a communication pattern in which every node initiates a broadcast. In this paper, we investigate the problem of building a unique cast tree of minimum total energy, which we call Minimum Unique Cast (MUC) tree, to be used for all-to-all broadcast. The MUC tree is unoriented and unrooted. We study three known heuristics for the minimum-energy broadcast problem: the Broadcast Incremental Power (BIP) algorithm, the Wireless Multicast Advantage-conforming Minimum Spanning Tree (WMA-conforming MST) algorithm, and the Iterative Maximum-Branch Minimization (IMBM) algorithm. Experimental results conducted on various types of networks are reported. We show that neither of these methods is best overall for building all-to-all broadcast trees.
On the complexity of finding gapped motifs
Authors: Morris Michael, François Nicolas, Esko Ukkonen
Venue: Journal of Discrete Algorithms (2010)

A gapped pattern is a sequence consisting of regular alphabet symbols and of joker symbols that match any alphabet symbol. The content of a gapped pattern is defined as the number of its non-joker symbols. A gapped motif is a gapped pattern that occurs repeatedly in a string or in a set of strings. The aim of this paper is to study the complexity of several gapped-motif-finding problems. The following three decision problems are shown NP-complete, even if the input alphabet is binary. (i) Given a string T and two integers c and q, decide whether or not there exists a gapped pattern with content c (or more) that occurs in T at q distinct positions (or more). (ii) Given a set of strings S and an integer c, decide whether or not there exists a gapped pattern with content c that occurs at least once in each string of S. (iii) Given m strings with the same length, and two integers c and q, decide whether or not there exists a gapped pattern with content c that matches at least q input strings. We also present a non-naive quadratic-time algorithm that solves the following optimization problem: given a string T and an integer q>=1, compute a maximum-content gapped pattern Q such that q consecutive copies of Q occur in T.
Admissible Rules of Łukasiewicz Logic
Authors: Emil Jeřábek
Venue: Journal of Logic and Computation (2010)

We investigate admissible rules of Łukasiewicz multi-valued propositional logic. We show that admissibility of multiple-conclusion rules in Łukasiewicz logic, as well as validity of universal sentences in free MV-algebras, is decidable (in PSPACE). 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
An evaluation of process warehousing approaches for business process analysis
Authors: Khurram Shahzad, Paul Johannesson
Venue: Proceedings of the International Workshop on Enterprises & Organizational Modeling and Simulation (2009)

Execution of a process model produces data that can be used for analysis and optimization of business processes. For several years, data warehouse (DW) technology has been used for analysis and decision making. A data warehouse developed for business processes is called a process warehouse. The capabilities of a process warehouse are seldom evaluated, since a generic framework that can be used for the evaluation is missing. Therefore, in this paper, we develop a generic framework called Process Analysis Framework (PAF) that can be used for evaluating analysis capabilities of a process warehouse. Furthermore, the framework has been used to evaluate various process warehousing approaches, collected through a comprehensive survey.
Research on integrating different methods of neural networks with case-based reasoning and rule-based system to infer causes of notebook computer breakdown
Authors: Shen-Tsu Wang, Wen-Tsann Lin
Venue: Expert Systems with Applications: An International Journal (2010)

Important issues for notebook computer companies include how to ascertain the problems of machines sent by customers, and then assigning those machines to the appropriate department for servicing; and how to maintain breakdown data to save both handling time and costs. However, in practical application, unreliable data decreases the model's accuracy, and thus, new methods are brought forward in rapid succession to increase accuracy when inferring causes of notebook computer breakdown. This study integrated several different methods, consisting of a neural network, with case-based reasoning (CBR) and a rule-based system (RBS) to propose a gradual model for inferring causes of notebook computer breakdown. It stressed that the model should have accuracy, elasticity, and transparent interpretability. The model contains three phases: data extracting, group indexing and knowledge creation. Initially, the data extraction phase uses a self-organizing map (SOM) and a revised learning vector quantization network method to reduce isomorphic data to similarity characteristic-based clustering, thus, improving data quality. Then, the group indexing phase establishes a clustering index prediction model based on a back-propagation network (BPN) and genetic algorithm (GA) to increase the efficiency of case selections. Then, the knowledge creation phase uses CBR and RBS to create a notebook computer breakdown case selection model to determine the breakdown cause. Finally, the experimental results show that data purification can actually improve the model's accuracy. The CBR with clustering index and rule-based reasoning has a better classification accuracy rate than either the CBR, without the clustering index and rule-based reasoning, or the traditional CBR, in addition, it provides a reference for inferring causes of notebook computer breakdown.
Hardware design of motion data decoding process for H.264/AVC
Authors: Kiwon Yoo, Kwanghoon Sohn
Venue: Image Communication (2010)

In H.264/AVC, motion data can be basically derived by the following two schemes: one is a typical spatial prediction scheme based on the DPCM and the other is a sophisticated spatiotemporal prediction scheme for the skipped motion data, formally referred to as a direct mode. We verified through instruction level profiling that when these schemes are combined with various H.264/AVC coding techniques, the computational burden to derive the motion data could be considerably aggravated. Specifically, its computational complexity amounts to maximally 55% of that of the overall syntax parsing process. In this paper, we aim at an efficient hardware design of the motion data decoding process for H.264/AVC, for which all the key design considerations are addressed in detail and respective rational answers are presented. As comparing the resulting hardware design with the processor-based solution, its effectiveness was clearly demonstrated. The proposed design was implemented with 43.2K logic gates and three on-chip memories of 3584 bits using Samsung Semiconductor's Standard Cell Library in 65nm L6LP process technology (SS65LP), and was capable of operating the H.264/AVC high-profile video bitstream of 1080p@60fps at 100MHz consuming 843@mW.
Reliable peers and useful resources: Searching for the best personalised learning path in a trust- and recommendation-aware environment
Authors: Vincenza Carchiolo, Alessandro Longheu, Michele Malgeri
Venue: Information Sciences: an International Journal (2010)

The evolution of the Web 2.0 and the intensive use of peer-to-peer networks allow us to access more and more information from disparate data sources than in the past, thus making life-long learning more effective. In this scenario, a critical issue still remains to be addressed: the reliability of resources, whether they can be recommended as useful and the reliability of peers, whether it is possible to trust them as providers. We propose to integrate these concepts with e-learning, proposing a model for searching for personalised and useful learning paths suggested by reliable (trusted) peers. We performed simulations on the Merlot data set enhanced with information extracted from Advogato, Epinions and Ariadne data sets, testing the efficiency and effectiveness of the proposed approach.
Feature selection algorithms to find strong genes
Authors: Paulo J. S. Silva, Ronaldo F. Hashimoto, Seungchan Kim, Junior Barrera, Leônidas O. Brandão, Edward Suh, Edward R. Dougherty
Venue: Pattern Recognition Letters (2005)

The cDNA microarray technology allows us to estimate the expression of thousands of genes of a given tissue. It is natural then to use such information to classify different cell states, like healthy or diseased, or one particular type of cancer or another. However, usually the number of microarray samples is very small and leads to a classification problem with only tens of samples and thousands of features. Recently, Kim et al. proposed to use a parameterized distribution based on the original sample set as a way to attenuate such difficulty. Genes that contribute to good classifiers in such setting are called strong. In this paper, we investigate how to use feature selection techniques to speed up the quest for strong genes. The idea is to use a feature selection algorithm to filter the gene set considered before the original strong feature technique, that is based on a combinatorial search. The filtering helps us to find very good strong gene sets, without resorting to super computers. We have tested several filter options and compared the strong genes obtained with the ones got by the original full combinatorial search.
The impact of DCF and PCF protocols in mobile WLANs
Authors: M. AL-Rousan, O. Abu-Rahmeh
Venue: International Journal of Modelling and Simulation (2008)

This paper presents a new analytical model to compute the performance of the IEEE802.11 standards. The model is simple, but nevertheless exceedingly accurate, which can be used to compute the throughput and delay for all access mechanisms supported by the IEEE802.11 standard. These mechanisms include the distributed coordination function (DCF), the DCF with RTS/CTS, and the point coordination function (PCF). Using the new model, we provide an extensive throughput and delay performance evaluation of the above mentioned access mechanisms, in the assumption of noisy channel and finite number of terminals. In addition, the evaluation study took into account the impact of the presence of "hidden stations" and the possibility of "capture" on the performance of wireless networks.
Nonlinear problem of active sound control
Authors: S. V. Utyuzhnikov
Venue: Journal of Computational and Applied Mathematics (2010)

We consider the problem of active sound control, in which some domain is protected from the field generated outside. The active shielding is realized via the implementation of additional sources in such a way that the total contribution of all sources leads to the wanted effect. Mathematically the problem is reduced to seeking the source terms satisfying some a priori described requirements and belongs to the class of inverse source problems. From the application standpoint, this problem can be closely related to active noise shielding and active vibration. It is important that along with unwanted field to be shielded a wanted field is accepted in the analysis. The solution to the problem requires only the knowledge of the total field at the perimeter of the shielded domain. For the first time the active shielding sources are obtained for the nonlinear statement of the problem. It is obtained via the theory of potentials, and the solution is represented in the form of a simple layer. For this purpose, the theory of Calderon-Ryaben'kii potentials is first extended to nonlinear formulations. In the solution, we also take into account the feedback of the secondary sources on the input data.
Robust static output feedback controller synthesis using Kharitonov's theorem and evolutionary algorithms
Authors: R. Toscano, P. Lyonnet
Venue: Information Sciences: an International Journal (2010)

This paper presents a simple but effective tuning strategy for robust static output feedback (SOF) controllers with minimal quadratic cost in the context of multiple parametric uncertainties. Finding this type of controller is known to be computationally intractable using conventional techniques. This is mainly due to the non-convexity of the resulting control problem, which has a fixed structure. To solve this kind of control problem easily and directly, without using any complicated mathematical manipulations, we utilize Kharitonov's theorem and an evolutionary algorithm (EA) for the resolution of the underlying constrained optimization problem. Using Kharitonov's theorem, a family of bounded, robustly stable static output feedback controllers can be defined and EA is used to select the controller that ensures a minimal quadratic cost within this family. The resulting tuning strategy is applicable to both stable and unstable systems, without any limitations on the order of the process to be controlled. A numerical study was conducted to demonstrate the validity of the proposed tuning procedure.
Secure transcoders for single layer video data
Authors: Nithin Thomas, David Redmill, David Bull
Venue: Image Communication (2010)

This paper considers the use of selective encryption systems for compressed video data that can support transcoding of the encrypted bit-streams without the need for decryption and re-encryption. The focus is on the use of the H.264 video codec. However, the concepts can be easily extended to any video coding standard. I-frame encryption encrypts only the intra frames, making it suitable for use with modified interframe transcoders that operate only on P and B frames. These interframe transcoders are found to offer improved performance for un-encrypted data, due to the temporal propagation of the higher quality of I-frames. The operations of both interframe open loop transcoding and Fast Pixel Domain Transcoding (FPDT) are unaffected by I-frame encryption yielding identical results. However, the lack of I-frame data causes a significant drift problem when I-frame encryption is used with a more complete Cascaded Pixel Domain Transcoder (CPDT). A modified CPDT is proposed, called Intra Block Copy (IBC) transcoding, which offers improved performance at the expense of a reduced range of possible output bitrates. Sign bit encryption systems such as Real-time Video Encryption Algorithm (RVEA) offer improved security compared to I-frame encryption. However transcoding this data can result in some sign bits being omitted causing a loss of cipher synchronization. A novel sign bit encryption technique called Synchronous Video Encryption Algorithm (SVEA) is proposed that preserves the cipher synchronization. While the operation of open loop transcoding systems is unaffected, the encryption interferes with the drift compensation in the more complex transcoders, leading to reduced performance.
Application of mother wavelet functions for automatic gear and bearing fault diagnosis
Authors: J. Rafiee, M. A. Rafiee, P. W. Tse
Venue: Expert Systems with Applications: An International Journal (2010)

This paper introduces an automatic feature extraction system for gear and bearing fault diagnosis using wavelet-based signal processing. Vibration signals recorded from two experimental set-ups were processed for gears and bearing conditions. Four statistical features were selected: standard deviation, variance, kurtosis, and fourth central moment of continuous wavelet coefficients of synchronized vibration signals (CWC-SVS). In this research, the mother wavelet selection is broadly discussed. 324 mother wavelet candidates were studied, and results show that Daubechies 44 (db44) has the most similar shape across both gear and bearing vibration signals. Next, an automatic feature extraction algorithm is introduced for gear and bearing defects. It also shows that the fourth central moment of CWC-SVS is a proper feature for both bearing and gear failure diagnosis. Standard deviation and variance of CWC-SVS demonstrated more appropriate outcome for bearings than gears. Kurtosis of CWC-SVS illustrated the acceptable performance for gears only. Results also show that although db44 is the most similar mother wavelet function across the vibration signals, it is not the proper function for all wavelet-based processing.
Real coded genetic algorithm for optimal parameters selection in circular Mellin feature extractors
Authors: V. S. Vyas, P. P. Rege
Venue: International Journal of Computers and Applications (2008)

Texture is an important clue in region-based segmentation of images. Robust rotation and scale-invariant texture are important for digital image libraries and multimedia databases. Texture feature extraction operators, which comprise linear filtering followed by postprocessing, are considered. The CMF (Circular Mellin Feature) represents the spectral decomposition of the image scene in the polar-log coordinate system and is invariant to both scale and orientation of the target texture pattern. CMFs are used for rotation and scale-invariant texture classification. The image and CMFs are correlated, due to which the unique shift invariance property of the correlator architecture is also coupled. CMFs are based on log polar coordinate system. In this paper we present Real coded Genetic Algorithm (RcGA) for the parameter selection of CMFs. The simple genetic algorithm (GA) is search algorithms based on the mechanics of natural selection and genetics. It involves copying and swapping partial strings of data. A modified genetic algorithm is the RcGA, which basically employs real value vectors for representation of the chromosomes, and is widely applied to many optimization problems.
Plane-based external camera calibration with accuracy measured by relative deflection angle
Authors: Chunhui Cui, King Ngi Ngan
Venue: Image Communication (2010)

In this paper, we present an efficient external calibration technique for a typical multi-camera system. The technique is very handy in practice using a simple planar pattern. Based on homography, three different pair-wise estimation algorithms are proposed to recover the rigid rotation and translation between neighboring cameras. By registering the accurate and reliable partial calibrated structures, the complete calibration of a multi-camera system can be accomplished. In order to evaluate and compare the calibration results for different camera setups, a novel accuracy metric is introduced based on the deflection angles of projection rays. Experimental results using both simulated and real data are presented to verify the validity and performance of the proposed method.