ppxscal/embedding_network huggingface dataset:
Lighting Direction Estimation in Perspective Shape from Shading by Genetic Algorithm
Authors: Chi Kin CHOW, Shiu Yin YUEN
Venue: Proceedings of the Fourth Canadian Conference on Computer and Robot Vision (2007)

In oblique shape from shading (SfS), the lighting (illumination) direction is essential for recovering the 3D surface of a shaded image. On the other hand, Fast Marching Methods (FMM) are SfS algorithms that use the mechanism of wave propagation to reconstruct the surface. In this paper, the estimation of lighting direction is addressed and we model it as an optimization problem. The idea is to minimize the inconsistency of wave propagation of FMM during the reconstruction. As the consistency of wave propagation is a multi-modal function, genetic algorithm (GA) is utilized to determine the lighting direction. Experimental results on four oblique SfSs with an unknown lighting direction are presented to demonstrate the performance of the proposed algorithm.
Key-dependent Message Security under Active Attacks--BRSIM/UC-Soundness of Symbolic Encryption with Key Cycles
Authors: Michael Backes, Birgit Pfitzmann, Andre Scedrov
Venue: Proceedings of the 20th IEEE Computer Security Foundations Symposium (2007)

Key-dependent message security, short KDM security, was introduced by Black, Rogaway and Shrimpton to address the case where key cycles occur among encryptions, e.g., a key is encrypted with itself. It was mainly motivated by key cycles in Dolev-Yao models, i.e., symbolic abstractions of cryptography by term algebras, and a corresponding soundness result was later shown by Adao et al. However, both the KDM definition and this soundness result do not allow the general active attacks typical for Dolev-Yao models and for security protocols in general. We extend these definitions so that we can obtain a soundness result under active attacks.We first present a definition AKDM as a KDM equivalent of authenticated symmetric encryption, i.e., it provides chosen-ciphertext security and integrity of ciphertexts even for key cycles. However, this is not yet sufficient for the desired soundness, and thus we give a definition DKDM that additionally allows limited dynamic revelation of keys.We show that this is sufficient for soundness, even in the strong sense of blackbox reactive simulatability (BRSIM)/UC and including joint terms with other operators. We also present constructions of schemes secure under the new definitions, based on current KDM-secure schemes. Moreover, we explore the relations between the new definitions and existing ones for symmetric encryption in detail, in the sense of implications or separating examples for almost all cases.
A Grid-based Parallel Approach of the Multi-Objective Branch and Bound
Authors: M. Mezmaz, N. Melab, E-G. Talbi
Venue: Proceedings of the 15th Euromicro International Conference on Parallel, Distributed and Network-Based Processing (2007)

The Branch and Bound (B&B) algorithm is one of the most used methods to solve in an exact way combinatorial optimization problems. This article focuses on the multi-objective version of this algorithm, and proposes a new parallel approach adapted to grid computing systems. This approach addresses several issues related to the characteristics of the algorithm itself and the properties of grid computing systems. Validation is performed by experimenting the approach on a bi-objective flow-shop problem instance that has never been solved exactly. Solving this instance, after several days of computation on a grid of more than 1000 processors, belonging to 7 distinct clusters, and the obtained results prove the e±ciency of the proposed approach.
Impulse noise reduction in medical images with the use of switch mode fuzzy adaptive median filter
Authors: Abdullah Toprak, İnan Güler
Venue: Digital Signal Processing (2007)

In this paper, a novel fuzzy adaptive median filter is presented for the noise reduction in MR images corrupted with heavy impulse (salt&pepper) noise. We propose a switch mode fuzzy adaptive median filter (SMFAMF) for removing highly corrupted salt&pepper noise without destroying edges and details in the image. The SMFAMF filter is an improved version of adaptive median filter (AMF) in order to reduce additive impulse noise in the images. The proposed filter can preserve details in the images better than AMF while suppressing additive salt&pepper or impulse type noises. In this paper, we placed our preference on bell-shaped membership function with adaptive parameters instead of triangular membership function without variable coefficients in order to observe better results. Experiments with the magnetic resonance (MR) image from healthy subject, an MR image having the opaque material, and an MR image having disease demonstrate the mean square error (MSE), root mean square error (RMSE), signal-to-noise ratio (SNR), and peak signal-to-noise ratio (PSNR) of the proposed method. The results show that the proposed method can be useful for MR images with impulse type noises.
Block motion estimation using wavelet filtering
Authors: H. F. Ates
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 04 (2000)

Block matching motion compensation achieves savings in residual error energy at the cost of motion vector bit rate. While this tradeoff has proven valuable for many video sequences, there are many obvious examples of blocks for which the cost of motion vectors is not offset by the gains of motion compensation. This paper proposes a multiresolution framework for motion compensated prediction that offers a richer set of options for trading off motion compensation accuracy against the cost of motion vectors. The method improves the prediction at motion boundaries and on covered/uncovered regions, while reducing the bit rate by using less accurate motion vectors in smoother regions. The new algorithm is compared to the full-search block matching in various simulations, and the results show that the algorithm achieves a 10 to 30% reduction in motion vector bit rate. These saving are particularly important in low bit rate applications where motion overhead constitutes a significant percentage of overall bit rate.
Using Tcl to rapidly develop a scalable engine for processing dynamic application logic
Authors: Greg Barish
Venue: Proceedings of the 6th conference on Annual Tcl/Tk Workshop, 1998 - Volume 6 (1998)

At Healtheon, we used Tcl to rapidly develop a scalable, high performance rule engine for processing dynamic application logic. The nature of our application requirements, plus the challenge of delivering robust software in a timely manner made Tcl an optimal overall choice in our deployment. We were able to improve rule processing performance by careful language construction and support for concurrent execution. We developed a mechanism for implementing data-driven language extensions, called rule concepts, which allowed us to present a customized language for each client, and encouraged rule reusability. Our experience with using Tcl in our application system was also representative of software engineering choices that small companies often make in pursuit of rapidly developing a well-balanced system solution.
Using the domain name system for system break-ins
Authors: Steven M. Bellovin
Venue: Proceedings of the 5th conference on USENIX UNIX Security Symposium - Volume 5 (1995)

The DARPA Internet uses the Domain Name System (DNS), a distributed database, to map host names to network addresses, and vice-versa. Using a vulnerability first noticed by P.V. Mockapetris, we demonstrate how the DNS can be abused to subvert system security. We also show what tools are useful to the attacker. Possible defenses against this attack, including one implemented by Berkeley in response to our reports of this problem, are discussed, and the limitations on their applicability are demonstrated. This paper was written in 1990, and was withheld from publication by the author. The body of the paper is unchanged, even to the extreme of giving the size of the Internet as 200,000 hosts. An epilogue has been added that discusses why it was held back, and why it is now being released.
Comparison of two architectures for implementation of the discrete cosine transform
Authors: I. Sundsbo
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1996. on Conference Proceedings., 1996 IEEE International Conference - Volume 06 (1996)

A new DCT architecture developed by Mou and Jutand (1991) is compared to an architecture based on distributed arithmetic with ROMs realized as random logic. Both architectures have been implemented in 0.8 /spl mu/m CMOS technology and optimized with different constraints on area and timing. The results reveal that for HDTV applications the design with distributed arithmetic is superior, with lower power consumption and less than half the chip area.
Blade-Vortex Interaction Airloads Prediction Using Multidisciplinary Coupling
Authors: Joon Lim, Mark Potsdam, Roger Strawn, Ben Sim, Tor Nygaard
Venue: Proceedings of the HPCMP Users Group Conference (2006)

Predictions of blade-vortex interaction (BVI) noise, using blade airloads obtained from a coupled aerodynamic, structural, and acoustics methodology, are presented. This methodology uses an iterative, loosely-coupled trim strategy for exchanging information between the computational fluid dynamics (CFD) code OVERFLOW-2 and the computational structural dynamics (CSD) and rotorcraft comprehensive code CAMRAD-II. Results are compared to the HART-II rotor baseline conditions. It is shown that this state-of-the-art CFD/CSD approach is able to capture BVI induced blade airloads and noise radiation characteristics. Predicted BVI airloads on the advancing and retreating sides agree well with the measured data. Although the BVI airloads and noise amplitudes are generally under-predicted, the CFD/CSD coupled methodology provides an overall noteworthy improvement over the lifting line aerodynamics with free-wake models typically used for CSD comprehensive analysis.
Edge Filtering Using Orientation Entropy
Authors: A. K. Das, P. K. Mitra, S. K. Ghosh, A. K. Ray
Venue: Proceedings of the International Conference on Computing: Theory and Applications (2007)

The paper introduces the concept of orientation entropy for quantifying the propensity of a pixel belonging to the edge. Intensity variation at a pixel is measured as an integral of a logarithmic function over all possible direction which represents the heterogeneity of intensity variation in the neighborhood of that point. This is unlike traditional edge filters which uses divergence operator considering the maximum intensity variation among all possible directions. The proposed entropic filter is found to provide visually superior edges for a number of benchmark images considered in our experiments.
Pervasive Personal Computing in an Internet Suspend/Resume System
Authors: Mahadev Satyanarayanan, Benjamin Gilbert, Matt Toups, Niraj Tolia, Ajay Surie, David R. O'Hallaron, Adam Wolbach, Jan Harkes, Adrian Perrig, David J. Farber, Michael A. Kozuch, Casey J. Helfrich, Partho Nath, H. Andres Lagar-Cavilla
Venue: IEEE Internet Computing (2007)

The Internet Suspend/Resume model of mobile computing cuts the tight binding between PC state and PC hardware. By layering a virtual machine on distributed storage, ISR lets the VM encapsulate execution and user customization state; distributed storage then transports that state across space and time. This article explores the implications of ISR for an infrastructure-based approach to mobile computing. It reports on experiences with three versions of ISR and describes work in progress toward the OpenISR version.
Approximate CFAR signal detection in strong low rank non-Gaussian interference
Authors: I. P. Kirsteins
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2001. on IEEE International Conference - Volume 05 (2001)

Recent work suggests that the performance of conventional Gaussian-based adaptive methods can degrade severely in correlated non-Gaussian interference. We have addressed this problem by developing a new generalized likelihood ratio test (GLRT) for detecting a signal in unknown, strong non-Gaussian low rank interference plus white Gaussian noise which does not need detailed knowledge of the non-Gaussian distribution. The optimality of the proposed GLRT detector is established using perturbation expansions of the test statistic to show that it is closely related to the UMPI (uniformly most powerful invariant) test for this problem. Computer simulations indicate that the new detector significantly outperforms standard adaptive methods in non-Gaussian interference and is robust.
An inverted computing curriculum: preparing graduates to build quality systems
Authors: A. J. LaSalle
Venue: Proceedings of the Frontiers in Education Conference,1997. on 27th Annual Conference. Teaching and Learning in an Era of Change. - Volume 01 (1997)

Employers of graduates of traditional computing curricula lament that new hires are unable to integrate into project teams, understand, develop or manage large systems, use software development tools, comply with industry and organizational standards, understand and practice quality precepts, or effectively communicate orally or in writing. By and large, traditional computing curricula produce graduates who are prepared to work alone on small projects that are rarely deployed. If we are to close the gap between the profile of the successful computing practitioner and the profile of the current graduate, some radical changes in curricula must be instituted. This paper describes current improvement efforts that are unfolding and experiences with transferring those efforts into the classroom.
A silence compression algorithm for multi-rate/dual-bandwidth MPEG-4 CELP standard
Authors: M. Serizawa
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 02 (2000)

This paper proposes a silence compression algorithm operating at multi-rates (MR) and with dual-bandwidths (DB), a narrowband and a wideband, for the MPEG-4 CELP standard. The MR/DB operations are implemented by a variable-frame-size/dual-bandwidth voice activity detection (VF/DB-VAD) module with domain conversions of the input signal, and a variable frame-size comfort noise generator (VF-CNG). The CNG module adaptively controls the power smoothing of the decoded signal to improve the coding quality. The algorithm also employs a dual-rate discontinuous transmission (DR-DTX) module to reduce an average transmission bit rate during silence periods. The subjective test results show that the proposed silence compression algorithm gives no degradation in coding quality for clean and noisy speech signals. These signals include about 20 to 30% nonspeech frames and the average transmission bit rates are reduced by 20 to 40%. The proposed algorithm has been standardized as a part of the ISO/IEC MPEG-4 CELP version 2.
Student Project Collaboration Using Wikis
Authors: Joseph Chao
Venue: Proceedings of the 20th Conference on Software Engineering Education & Training (2007)

A wiki is a web tool that allows users to easily create and edit web pages collaboratively. The ease-of-editing feature and accessibility from anywhere by anyone make wikis ideal for project collaboration. Although the wiki was introduced more than ten years ago, its use is relatively new in academia. This research explores the potential uses of wikis in Software Engineering, especially for software project team collaboration and communication. The author introduced wikis in a project-based software engineering course, and students soon discovered a number of innovative ways in which wikis can augment collaborative software development activities. A student survey indicates that vast majority of students found the wiki to be a good tool for project collaboration, and most of them plan to use wikis for future projects even if not required to do so.
Models and algorithms to determine cerebral activation using near infrared spectroscopy
Authors: Kambiz Alavi
Venue:  (2006)

The specific aims of this dissertation were to develop: (1) Correlations between experimental protocols and oxygenated, deoxygenated, and total hemoglobin concentrations in the brain; (2) Mathematical models to associate blood flow and oxygen consumption rate of the activated brain regions with measured hemodynamic changes; (3) A phantom that models brain vasculature compliance to validate developed mathematical models in a controlled setup. The primary imaging modality used in the experimentation phase of this research was near infrared spectroscopy. Previously published multimodality measurements were also used to validate the mathematical models.The single compartment Windkessel model was extended to describe flow-volume dynamics during long duration stimulus and include oxygen transport to tissue. An inductive multi-compartment model was developed which enables the estimation of compartmentalized hemodynamic changes with the modeling of measured oxy- and deoxyhemoglobin changes based on a pseudo-Bayesian framework for multimodality data. In addition, a solution to the single and multi-compartment deductive neurovascular model was also developed. This model defines the relationship between the presented stimulus and the neural activity it elicits which in turn gives rise to the vascular changes. Finally a vascular phantom was developed in the laboratory to validate the flow - volume relationships using compliant vasculature.
A Testbed with a Practical Smart Antenna for Directional MAC Protocols in Ad hoc Networks
Authors: Hikaru Mitsuhashi, Masahiro Watanabe, Sadao Obana, Masaki Bandai, Takashi Watanabe
Venue: Proceedings of the 21st International Conference on Advanced Information Networking and Applications Workshops - Volume 02 (2007)

Recently, several MAC protocols using directional antennas have been proposed for ad hoc networks, which are mainly evaluated by computer simulations. This paper develops a MAC protocol testbed called TRNC/ESPAR for ad hoc networks, which enables the evaluation of directional MAC protocols as well as omni-directional protocols. At first, we investigate the requirements for the testbed. Based on them, TRNC/ESPAR is designed to consist of ESPAR as a practical smart antenna, IEEE 802.15.4 as a wireless module, GPS and gyro modules to support a location dependant MAC. After describing the detail design, we investigate the basic performance of the testbed and implement CSMA/CA. Implementing one of directional MAC protocols with 4 nodes, DMAC shows that the protocol doubles the throughput compared with CSMA/CA because of SDMA effect but if the pair is too near DMAC throughput degraded in a real environment, which could not be found without the testbed.
Adjustable Approach for Collision Detection in Virtual Prototype Environments
Authors: Mauro Figueiredo
Venue: Proceedings of the Geometric Modelling and Imaging (2007)

Collision detection is an important task for the simulation of interactions in virtual assembly. This paper presents a novel collision detection algorithm that uses bounding volumes (BV) of different complexity to find intersecting surfaces interactively. This approach uses the surface knowledge available from the CAD model efficiently to build a hierarchical collision detection algorithm. This method also uses different types of bounding volumes with the advantage that is possible to choose the bounding volumes that are more suitable for each type of application. In this way, the user can allow the existence of different types of bounding volumes in simultaneous and he/her can adjust the selection of BVs to the most effective for the determination of intersecting surfaces.
Implementing a Professional Services Organization Using Type C Scrum
Authors: Brent Barton, Evan Campbell
Venue: Proceedings of the 40th Annual Hawaii International Conference on System Sciences (2007)

SolutionsIQ's Professional Services Division dramatically improved project quality and team productivity through the adoption of Scrum and Agile values, principles, and practices. The organization's original structure was typical of a consulting organization; functional silos (developers, testers, Project Managers) matrixed into project assignments. This model was misaligned with the team-based principals inherent in Scrum and Agile. This misaligned organizational structure created inefficiencies and obstacles (waste) in team and departmental function. In an effort to improve this misalignment, the authors designed and implemented an innovative organizational model based on Type C Scrum. This paper assumes the reader is generally familiar with Agile and Scrum basics, and provides a cursory definition of Type C; an advanced organization-wide extension of the simple Scrum project management wrapper. The paper provides a fairly detailed description of a specific instantiation of Scrum and Agile organizational design in a 400 person services business.
Byte me: a case for byte accuracy in traffic classification
Authors: Jeffrey Erman, Anirban Mahanti, Martin Arlitt
Venue: Proceedings of the 3rd annual ACM workshop on Mining network data (2007)

Numerous network traffic classification approaches have recently been proposed. In general, these approaches have focused on correctly identifying a high percentage of total flows. However, on the Internet a small number of "elephant" flows contribute a significant amount of the traffic volume. In addition, some application types like Peer-to-Peer (P2P) and FTP contribute more elephant flows than other applications types like Chat. In this opinion piece, we discuss how evaluating a classifier on flow accuracy alone can bias the classification results. By not giving special attention to these traffic classes and their elephant flows in the evaluation of traffic classification approaches we might obtain significantly different performance when these approaches are deployed in operational networks for typical traffic classification tasks such as traffic shaping. We argue that byte accuracy must also be used when evaluating the accuracy of traffic classification algorithms.
Semi-parametric optimization for missing data imputation
Authors: Yongsong Qin, Shichao Zhang, Xiaofeng Zhu, Jilian Zhang, Chengqi Zhang
Venue: Applied Intelligence (2007)

Missing data imputation is an important issue in machine learning and data mining. In this paper, we propose a new and efficient imputation method for a kind of missing data: semi-parametric data. Our imputation method aims at making an optimal evaluation about Root Mean Square Error (RMSE), distribution function and quantile after missing-data are imputed. We evaluate our approaches using both simulated data and real data experimentally, and demonstrate that our stochastic semi-parametric regression imputation is much better than existing deterministic semi-parametric regression imputation in efficiency and effectiveness.
New Attack Tricks Antivirus Software
Authors: Karen Heyman
Venue: Computer (2007)

With the advent of Web 2.0, hackers are using dynamic code obfuscation as a new way to spread malicious code and short-circuit the pattern-matching antivirus approach.
Space-Time Representation of Iterative Algorithms and the Design of Regular Processor Arrays
Authors: E. D. Kyriakis-Bitzaros, O. G. Koufopavlou, C. E. Goutis
Venue: Proceedings of the 1993 International Conference on Parallel Processing - Volume 03 (1993)

A novel space-time representation of iterative algorithms, which can be expressed in nested loop form and may include non-constant dependencies is proposed and a systematic methodology for their mapping onto regular processor arrays is presented. In contrast to previous design methodologies, the execution time of any variable instance is explicitly expressed in the Dependence Graph, by the construction of the Space-Time Dependence Graph (STDG). This approach avoids the uniformization step of the algorithm and the requirement for fully indexing the variables.