ppxscal/embedding_network huggingface dataset:
Ensemble of HMM classifiers based on the clustering validity index for a handwritten numeral recognizer
Authors: Albert Hung-Ren Ko, Robert Sabourin, Alceu de Souza Britto,  Jr.
Venue: Pattern Analysis Applications (2009)

A new scheme for the optimization of codebook sizes for Hidden Markov Models (HMMs) and the generation of HMM ensembles is proposed in this paper. In a discrete HMM, the vector quantization procedure and the generated codebook are associated with performance degradation. By using a selected clustering validity index, we show that the optimization of HMM codebook size can be selected without training HMM classifiers. Moreover, the proposed scheme yields multiple optimized HMM classifiers, and each individual HMM is based on a different codebook size. By using these to construct an ensemble of HMM classifiers, this scheme can compensate for the degradation of a discrete HMM.
Fast communication: Narrowband interference cancellation based on set-membership estimation in DCSK communication system
Authors: Yongquan Fan, Jiashu Zhang
Venue: Signal Processing (2009)

This paper presents set-membership estimation methods for narrowband interference cancellation (NBIC) in differential chaotic shift keying (DCSK) communication. Based on the boundedness of the chaotic carrier, two optimal bounding ellipsoid (OBE) algorithms are formulated, one with known and one with unknown interference parameters. Compared with the Kalman filter and recursive least-squares (RLS) algorithms, the proposed NBIC methods are computationally efficient due to the discerning update features that can estimate interfering signals with only a fraction of the observations. Simulation results illustrate that the proposed NBIC methods can suppress autoregressive (AR) or sinusoidal interference effectively.
Image Fusion for Enhanced Visualization: A Variational Approach
Authors: Gemma Piella
Venue: International Journal of Computer Vision (2009)

We present a variational model to perform the fusion of an arbitrary number of images while preserving the salient information and enhancing the contrast for visualization. We propose to use the structure tensor to simultaneously describe the geometry of all the inputs. The basic idea is that the fused image should have a structure tensor which approximates the structure tensor obtained from the multiple inputs. At the same time, the fused image should appear `natural' and `sharp' to a human interpreter. We therefore propose to combine the geometry merging of the inputs with perceptual enhancement and intensity correction. This is performed through a minimization functional approach which implicitly takes into account a set of human vision characteristics.
Search Engines: Information Retrieval in Practice, 1st edition
Authors: Bruce Croft, Donald Metzler, Trevor Strohman
Venue:  (2009)

KEY BENEFIT: Written by a leader in the field of information retrieval, this text provides the background and tools needed to evaluate, compare and modify search engines. KEY TOPICS: Coverage of the underlying IR and mathematical models reinforce key concepts. Numerous programming exercises make extensive use of Galago, a Java-based open source search engine. MARKET: A valuable tool for search engine and information retrieval professionals.
Wii all play: the console game as a computational meeting place
Authors: Amy Voida, Saul Greenberg
Venue: Proceedings of the 27th international conference on Human factors in computing systems (2009)

In this paper, we present results from a qualitative study of collocated group console gaming. We focus on motivations for, perceptions of, and practices surrounding the shared use of console games by a variety of established groups of gamers. These groups include both intragenerational groups of youth, adults, and elders as well as intergenerational families. Our analysis highlights the numerous ways that console games serve as a computational meeting place for a diverse population of gamers.
Studies of defect states of ZnO thin films under different annealing conditions
Authors: Hooyoung Song, Jae-Hoon Kim, Eun Kyu Kim
Venue: Microelectronics Journal (2009)

ZnO thin films were grown by the pulsed laser deposition technique on c-plane sapphire substrates at a substrate temperature of 500^oC with 1x10^-^4Torr ambient gas. After the deposition process, ZnO thin films were annealed at 1000^oC for 5min under N"2 or O"2 ambient gas, respectively. In the X-ray patterns, the (002) peak of the annealed sample was shifted from that of the as-grown sample, which indicates a reduced lattice constant of about 1%. Even though the X-ray diffraction patterns in the samples annealed under O"2 and N"2 annealing gases were almost the same, photoluminescence spectra showed the generation of a shallow level with a few meV, and deep-level states were generated at E"v+0.594eV. In addition, a defect state appeared at E"c-0.607eV, which originated from hydrogen plasma irradiation on the ZnO sample.
Behavior-driven visualization recommendation
Authors: David Gotz, Zhen Wen
Venue: Proceedings of the 13th international conference on Intelligent user interfaces (2009)

We present a novel approach to visualization recommendation that monitors user behavior for implicit signals of user intent to provide more effective recommendation. This is in contrast to previous approaches which are either insensitive to user intent or require explicit, user specified task information. Our approach, called Behavior-Driven Visualization Recommendation (BDVR), consists of two distinct phases: (1) pattern detection, and (2) visualization recommendation. In the first phase, user behavior is analyzed dynamically to find semantically meaningful interaction patterns using a library of pattern definitions developed through observations of real-world visual analytic activity. In the second phase, our BDVR algorithm uses the detected patterns to infer a user's intended visual task. It then automatically suggests alternative visualizations that support the inferred visual task more directly than the user's current visualization. We present the details of BDVR and describe its implementation within our lab's prototype visual analysis system. We also present study results that demonstrate that our approach shortens task completion time and reduces error rates when compared to behavior-agnostic recommendation.
Fast point multiplication on Koblitz curves: Parallelization method and implementations
Authors: Kimmo Järvinen, Jorma Skyttä
Venue: Microprocessors Microsystems (2009)

Point multiplication is required in every elliptic curve cryptosystem and its efficient implementation is essential. Koblitz curves are a family of curves defined over F"2"^"m allowing notably faster computation. We discuss implementation of point multiplication on Koblitz curves with parallel field multipliers. We present a novel parallelization method utilizing point operation interleaving. FPGA implementations are described showing the practical feasibility of our method. They compute point multiplications on average in 4.9@ms, 8.1@ms, and 12.1@ms on the standardized curves NIST K-163, K-233, and K-283, respectively, in an Altera Stratix II FPGA.
Approximated consistency for the automatic recording constraint
Authors: Meinolf Sellmann
Venue: Computers and Operations Research (2009)

We introduce the automatic recording constraint (ARC) that can be used to model and solve scheduling problems where tasks may not overlap in time and the tasks linearly exhaust some resource. Since achieving generalized arc-consistency for the ARC is NP-hard, we develop a filtering algorithm that achieves approximated consistency only. Numerical results show the benefits of the new constraint on three out of four different types of benchmark sets for the automatic recording problem. On these instances, run-times can be achieved that are orders of magnitude better than those of the best previous constraint programming approach.
Research on Channel Quantization Algorithm of Time Correlated Channels
Authors: Zhenjie Feng, Taiyi Zhang, Erlin Zeng
Venue: IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences (2008)

Focusing on time correlation of real communication channels, a channel quantization algorithm based on finite state vector quantization (FSVQ) is proposed. Firstly channels are partitioned into finite states, then codebooks corresponding to each state are constructed, which are used to quantize channels transferred from corresponding states. Further, the state transition function is designed to ensure the synchronization between transmitter and receiver. The proposed algorithm can achieve improved performance with the same feedback load compared with classical memoryless channel quantizer without consideration of the influence of time correlation. Simulation results verify the effectiveness of the proposed algorithm.
A Card-Handling Tool for Multimedia
Authors: Yoshihiro Ohmi, Kazuhisa Kawai, Hajime Ohiwa
Venue: Proceedings of the 1999 IEEE International Conference on Multimedia Computing and Systems - Volume 02 (1999)

The multimedia application system based on the card-handling is described. The card-handling is a useful method for knowledge representation, thinking and document writing. We have implemented a card-handling tool KJ-Editor that was specially considered to be easy to handle, and a user can operate on large working space. Moreover, it is expected that we can make flexible thinking and effective communication through using cards containing pictures or figures or through the oral presentation of the card-arrangement, and the spatial arranging has advantage of handling pictures and figures. Therefore, in order to handle the multimedia data, the framework of the tool was redesigned and a prototype system was realized. We also experimented on a requirement analysis using the prototype, and found an effectiveness of the system.
Modelling of Chaotic Time Series Using Minimax Probability Machine Regression
Authors: Jiancheng Sun
Venue: Proceedings of the 2009 WRI International Conference on Communications and Mobile Computing - Volume 01 (2009)

A state-of-the-art regression method called minimax probability machine is introduced to modelling the chaotic time series. Since the positive global Lyapunov exponents cause the errors in modelling of the chaotic time series to grow exponentially rapidly, a weighted term to the cost function is introduced to compensate this effect. Power spectrum and dynamic invariants involving Lyapunov exponents and correlation dimension are used as criterions to estimate the performance and then apply our method to the Lorenz system. The simulation results show that the proposed method can capture the dynamics of the chaotic time series effectively.
Dynamic response of a torsional micromirror to electrostatic force and mechanical shock
Authors: Faraz Khatami, Ghader Rezazadeh
Venue: Microsystem Technologies (2009)

In this paper dynamic characteristics of a capacitive torsional micromirror under electrostatic forces and mechanical shocks have been investigated. A 2DOF model considering the torsion and bending stiffness of the micromirror structure has been presented. A set of nonlinear equations have been derived and solved by Runge&#x2013;Kutta method. The Static pull-in voltage has been calculated by frequency analyzing method, and the dynamic pull-in voltage of the micromirror imposed to a step DC voltage has been derived for different damping ratios. It has been shown that by increasing the damping ratio the dynamic pull-in voltage converges to static one. The effects of linear and torsional shock forces on the mechanical behavior of the electrostatically deflected and undeflected micromirror have been studied. The results have shown that the combined effect of a shock load and an electrostatic actuation makes the instability threshold much lower than the threshold predicted, considering the effect of shock force or electrostatic actuation alone. It has been shown that the torsional shock force has negligible influence on dynamic response of the micromirror in comparison with the linear one. The results have been calculated for linear shocks with different durations, amplitudes, and input times.
Detecting low-profile scans in TCP anomaly event data
Authors: J. Treurniet
Venue: Proceedings of the 2006 International Conference on Privacy, Security and Trust: Bridge the Gap Between PST Technologies and Business Services (2006)

Anomalous connections in TCP traffic can be detected using a finite state machine model that reflects the progression of a TCP connection through a sequence of states via its control flags. Anomalies generated by this model can be associated with scanning activity. By storing these anomalies over time, it is possible to identify the presence of scanning activity by sorting the data with respect to source address, destination address and destination port. In particular, low-profile (slow and/or distributed) scans can be identified. The 1999 DARPA data was used to test the method, with no false negatives. Operational data was injected with crafted slow scan anomalies to test the false negative rate; all were successfully detected, along with numerous real scans. The storage requirements of the system are quite small, giving the ability to store scans for extremely long periods of time.
Report on the 4th international ERCIM workshop on software evolution and evolvability (Evol '08)
Authors: Michel Wermelinger, Paul Wernick, Ciarán Bryce
Venue: ACM SIGSOFT Software Engineering Notes (2009)

The 4th International ERCIM Workshop on Software Evolution and Evolvability (Evol '08) took place on 15-16 September 2008 in L'Aquila, co-located with the 23rd IEEE/ACM Conference on Automated Software Engineering (ASE). The workshop focused on research and practice related to the long-term evolution of software products. For the first time two separate events, devoted to practical and more abstract aspects of this area, combined into a single workshop which in its first iteration demonstrated the synergy hoped for from this combination.
Grid Deployment of Legacy Bioinformatics Applications with Transparent Data Access
Authors: Christophe Blanchet, Remi Mollon, Douglas Thain, Gilbert Deleage
Venue: Proceedings of the 7th IEEE/ACM International Conference on Grid Computing (2006)

Although grid computing offers great potential for executing large-scale bioinformatics applications, practical deployment is constrained by legacy interfaces. Most widely deployed bioinformatics were designed long before grid computing arose, and thus are created, tested, and validated in the familiar environment of a workstation. Most perform simple local I/O and have no facility for interfacing with a distributed system. Because of these limitations, users of bioinformatics applications are generally constrained to creating large local clustered systems in order to perform data analysis. In order to deploy these applications in wide-area grid systems, users require a transparent mechanism of attaching legacy interfaces to grid I/O systems. We have explored this problem by deploying several bioinformatics databases and programs for protein sequence analysis on the European EGEE grid. Using tools for transparent adaptation, we have connected legacy applications to the logical namespace provided by a replica manager, and compared the performance of remote access versus file staging. For common bioinformatics applications, we find that remote access has performance equal or better than simple file staging, with the added advantage that users are freed from stating the data needs of applications in advance.
Random Projections of Smooth Manifolds
Authors: Richard G. Baraniuk, Michael B. Wakin
Venue: Foundations of Computational Mathematics (2009)

We propose a new approach for nonadaptive dimensionality reduction of manifold-modeled data, demonstrating that a small number of random linear projections can preserve key information about a manifold-modeled signal. We center our analysis on the effect of a random linear projection operator &#x03a6;:&#x211d; N &#x2192;&#x211d;M , M<N, on a smooth well-conditioned K-dimensional submanifold &#x2133;&#x2282;&#x211d;N . As our main theoretical contribution, we establish a sufficient number M of random projections to guarantee that, with high probability, all pairwise Euclidean and geodesic distances between points on &#x2133; are well preserved under the mapping &#x03a6;. Our results bear strong resemblance to the emerging theory of Compressed Sensing (CS), in which sparse signals can be recovered from small numbers of random linear measurements. As in CS, the random measurements we propose can be used to recover the original data in &#x211d;N . Moreover, like the fundamental bound in CS, our requisite M is linear in the &#x201c;information level&#x201d; K and logarithmic in the ambient dimension N; we also identify a logarithmic dependence on the volume and conditioning of the manifold. In addition to recovering faithful approximations to manifold-modeled signals, however, the random projections we propose can also be used to discern key properties about the manifold. We discuss connections and contrasts with existing techniques in manifold learning, a setting where dimensionality reducing mappings are typically nonlinear and constructed adaptively from a set of sampled training data.
The Design of Expressive Cartoons for the Web - TINKY
Authors: Aldo Paradiso, Frank Nack, Georg Fries, Karlheinz Schuhmacher
Venue: Proceedings of the IEEE International Conference on Multimedia Computing and Systems - Volume 2 (1999)

Tinky is a design environment which allows the generation, modification and animation of 3D cartoon-faces, where the face model is not based on a set of independent parameters that control specific abstract muscle emulations, but is directed by a set of objects representing the elements of the face. In order to provide an easy to use authoring system producing standardised expressions and animations of web oriented cartoons, we adopt an object oriented approach for cartoon design and combine it with the authoring qualities of VRML and the standardised set of facial and body animation parameters defined by MPEG-4 SNHC. . We describe the underlying structure and functionality and provide design examples of the currently implemented system.
Modeling of a Vertical Cavity Surface Emitting Laser Containing a Multi-QW Heterostructure
Authors: N. N. Elkin, A. P. Napartovich, V. N. Troshchieva, D. V. Vysotsky
Venue: Numerical Analysis and Its Applications: 4th International Conference, NAA 2008, Lozenetz, Bulgaria, June 16-20, 2008. Revised Selected Papers (2009)

A vertical cavity surface emitting laser (VCSEL) is an object of numerical study in the present paper.The linear non-hermitian eigenvalue problem arises in the first stage when we consider a "cold" cavity and neglect changes of material characteristics induced by electromagnetic field. The round-trip operator technique and Krylov subspace methods were used for determination of eigenfunctions, which represent intra-cavity wave field distributions. Corresponding complex eigenvalues determine the wavelength shifts relative to reference value and threshold gains.The next stage of study relates to a case of a loaded cavity when self-consistent solving of a wave field equation and material equations is required. The eigenvalue problem for a non-linear operator must be solved to find the lasing electromagnetic field spatial profile and its frequency. The gain element of a typical VCSEL device comprises several quantum wells (QW). The charge carriers distributions in each of QW obey non-linear diffusion equation. The round-trip operator is a non-linear operator in this case, and its evaluation needs an iteration procedure. We propose the iteration procedure, which is applicable for a set of QW of any size and has computational costs growing linearly with number of QW.The computational procedures and results of calculations for a cylindrical VCSEL will be reported.
Computational issues associated with automatic calculation of acute myocardial infarction scores
Authors: J. B. Destro-Filho, S. J. S. Machado, G. T. Fonseca
Venue: EURASIP Journal on Advances in Signal Processing (2008)

This paper presents a comparison among the three principal acute myocardial infarction (AMI) scores (Selvester, Aldrich, Anderson-Wilkins) as they are automatically estimated from digital electrocardiographic (ECG) files, in terms of memory occupation and processing time. Theoretical algorithm complexity is also provided. Our simulation study supposes that the ECG signal is already digitized and available within a computer platform. We perform 1000 000 Monte Carlo experiments using the same input files, leading to average results that point out drawbacks and advantages of each score. Since all these calculations do not require either large memory occupation or long processing, automatic estimation is compatible with real-time requirements associated with AMI urgency and with telemedicine systems, being faster than manual calculation, even in the case of simple costless personal microcomputers.
Anonymity-Proof Voting Rules
Authors: Vincent Conitzer
Venue: Proceedings of the 4th International Workshop on Internet and Network Economics (2008)

A (randomized, anonymous) voting rule maps any multiset of total orders (aka. votes) over a fixed set of alternatives to a probability distribution over these alternatives. A voting rule f is false-name-proof if no voter ever benefits from casting more than one vote. It is anonymity-proof if it satisfies voluntary participation and it is false-name-proof. We show that the class of anonymity-proof neutral voting rules consists exactly of the rules of the following form. With some probability k f &thinsp;&isin;&thinsp;[0,1], the rule chooses an alternative uniformly at random. With probability 1&thinsp;&minus;&thinsp;k f , the rule first draws a pair of alternatives uniformly at random. If every vote prefers the same alternative between the two (and there is at least one vote), then the rule chooses that alternative. Otherwise, the rule flips a fair coin to decide between the two alternatives. We also show how the characterization changes if group strategy-proofness is added as a requirement.
Passages through time: chronicling users' information interaction history by recording when and what they read
Authors: Karl Gyllstrom
Venue: Proceedings of the 13th international conference on Intelligent user interfaces (2009)

The Passages system enhances information management by maintaining a detailed chronicle of all the text the user ever reads or edits, and making this chronicle available for rich temporal queries about the user's information workspace. Passages enables queries like, "which papers and web pages did I read when writing the 'related work' section of this paper?", and, "which of the emails in this folder have I skimmed, but not yet read in detail?" As time and interaction history are important attributes in users' recall of their personal information, effectively supporting them creates useful possibilities for information retrieval. We present methods to collect and make sense of the large volume of text with which the user interacts. We show through user evaluation the accuracy of Passages in building interaction history, and illustrate its capacity to both improve existing retrieval systems and enable novel ways to characterize document activity across time.