ppxscal/embedding_network huggingface dataset:
Decimation and SVD to estimate exponentially damped sinusoids in the presence of noise
Authors: S.-E. Fotinea
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2001. on IEEE International Conference - Volume 05 (2001)

A new state-space method for spectral estimation that performs decimation by factor two while it makes use of the full set of data available is presented. The proposed method, called DESE2, is based on singular value decomposition in order to estimate frequency, damping factor, amplitude and phase of exponentially damped sinusoids in the presence of noise. The DESE2 method is compared against some previously proposed methods for spectral estimation that lie among the most promising methods in the field of spectroscopy, where accuracy of parameter estimation is of utmost importance. Experiments performed on a typical simulated NMR signal prove the new method to be more robust, especially for low signal to noise ratio. The new method outperforms the other two not only by presenting lower failure rates but also by incorporating enhanced discriminative analysis while at the same time it benefits from the use of the full data set.
Effect of Medium Dispersivity on the Viscous Fingering Instability in Porous Media
Authors: Karim Ghesmat, Jalel Azaiez
Venue: Proceedings of the 21st International Symposium on High Performance Computing Systems and Applications (2007)

Flow processes that involve the displacement of a viscous fluid by a less viscous one often lead to a hydrodynamic instability known as viscous fingering. In this study the viscous fingering instability for anisotropic dispersive flows will be addressed. In order to understand the physics of the flow displacement, the basic equations of conservation of mass and momentum are solved for a two-dimensional porous medium. The linear stability of the flow is analyzed first. The flow is then modeled numerically using a highly accurate spectral method based on the Hartley transformation. The streamfunction and concentration fields are tracked using an iteration process for two dimensional flows in every time-step. In this study, different types of anisotropic dispersions are considered and their effects on finger patterns are examined. We will present physical discussion of how medium dispersivity affects hydrodynamics and could result in interesting instability schemes.
Ciphertext-Policy Attribute-Based Encryption
Authors: John Bethencourt, Amit Sahai, Brent Waters
Venue: Proceedings of the 2007 IEEE Symposium on Security and Privacy (2007)

In several distributed systems a user should only be able to access data if a user posses a certain set of credentials or attributes. Currently, the only method for enforcing such policies is to employ a trusted server to store the data and mediate access control. However, if any server storing the data is compromised, then the confidentiality of the data will be compromised. In this paper we present a system for realizing complex access control on encrypted data that we call Ciphertext-Policy Attribute-Based Encryption. By using our techniques encrypted data can be kept confidential even if the storage server is untrusted; moreover, our methods are secure against collusion attacks. Previous Attribute- Based Encryption systems used attributes to describe the encrypted data and built policies into user's keys; while in our system attributes are used to describe a user's credentials, and a party encrypting data determines a policy for who can decrypt. Thus, our methods are conceptually closer to traditional access control methods such as Role-Based Access Control (RBAC). In addition, we provide an implementation of our system and give performance measurements.
The Impact on Channel Correlation for MC-DS-CDMA System in Small-Scale Fading Environments
Authors: Joy Iong-Zong Chen
Venue: Wireless Personal Communications: An International Journal (2007)

In this research, the performance of an multi-carrier direct-sequence coded-division multiple-access (MC-DS-CDMA) system working in Nakagami fading channels with correlation characteristics is studied. In order to avoid the difficulty of explicitly obtaining the probability density function (pdf) for the signal-to-noise ratio (SNR) at the output of RAKE receiver, there is a pdf with the sum of Gamma will be varieties is applied in the derivative for bit error rate (BER) performance. Two cases, single- and multiple-user will be exemplified for validating the fact that the performance degradation of the MC-DS-CDMA is sensitive to the correlation coefficient of the fading channels. Besides, the assumption of partial band interference (PBI) between the subcarriers is considered in this evaluation.
Redundant features of design in blackboard (LMS) and user error
Authors: D. A. Quarless
Venue: ACM SIGCSE Bulletin (2007)

Assessment has become a ubiquitous and iterative activity of education. Instructional computing in its simplest terms involves the creation of integrated toolkits (resources) for use in the learning process. The increasing prevalence of Learning/Course Management Systems in higher education is providing some new opportunities to explore and assess the design of such systems in reaching their purpose as integrated platforms that create online learning environments. Certain web-based design features have some likeliness to result in user errors. Blackboard is such a case study.
Foundations of Autonomic Computing Development
Authors: Sam Lightstone
Venue: Proceedings of the Fourth IEEE International Workshop on Engineering of Autonomic and Autonomous Systems (2007)

The complexity of modern middleware, and software solutions, is growing at an exponential rate. Only self-managing, or autonomic computing technology can reasonably stem the confusion this complexity brings to bear on human administrators. While much has been published on "architecture" and "function" for producing such systems, little has been written about the engineering of self-managing systems as a distinct paradigm. In this paper we suggest a straw-man for engineering of autonomic systems that is based on two essential tracks: a set of engineering principles that should guide the planning of autonomic systems and their interfaces and secondly a set of mathematical foundations upon which such systems can best be constructed. These foundational attributes are intended to guide the thinking of R&D organizations pursuing the development of autonomic computing capability. The role of architecture and standards is also discussed, highlighting their role in inter-component management.
Thermally robust clocking schemes for 3D integrated circuits
Authors: Mosin Mondal, Andrew J. Ricketts, Sami Kirolos, Tamer Ragheb, Greg Link, N. Vijaykrishnan, Yehia Massoud
Venue: Proceedings of the conference on Design, automation and test in Europe (2007)

3D integration of multiple active layers into a single chip is a viable technique that greatly reduces the length of global wires by providing vertical connections between layers. However, dissipating the heat generated in the 3D chips possesses a major challenge to the success of the technology and is the subject of active current research. Since the generated heat degrades the performance of the chip, thermally insensitive/adaptive circuit design techniques are required for better overall system performance. In this paper, we propose a thermally adaptive 3D clocking scheme that dynamically adjusts the driving strengths of the clock buffers to reduce the clock skew between terminals. We investigate the relative merits and demerits of two alternative clock tree topologies in this work. Simulation results demonstrate that our adaptive technique is capable of reducing the skew by 61.65% on the average, leading to much improved clock synchronization and design performance in the 3D realm.
Concierge: a service platform for resource-constrained devices
Authors: Jan S. Rellermeyer, Gustavo Alonso
Venue: Proceedings of the 2nd ACM SIGOPS/EuroSys European Conference on Computer Systems 2007 (2007)

As mobile and embedded devices become widespread, the management and configuration of the software in the devices is increasingly turning into a critical issue. OSGi is a business standard for the life cycle management of Java software components. It is based on a service oriented architecture where functional units are decoupled and components can be managed independently of each other. However, the focus continuously shifts from the originally intended area of small and embedded devices towards large-scaled enterprise systems. As a result, implementations of the OSGi framework are increasingly becoming more heavyweight and less suitable for smaller computing devices. In this paper, we describe the experience gathered during the design of Concierge, an implementation of the OSGi specification tailored to resource-constrained devices. Comprehensive benchmarks show that Concierge performs better than existing implementations and consumes less resources.
Wireless Forensic Analysis Tools for Use in the Electronic Evidence Collection Process
Authors: Benjamin Turnbull, Jill Slay
Venue: Proceedings of the 40th Annual Hawaii International Conference on System Sciences (2007)

This paper discusses the need for both a series of electronic tools and procedural changes to the evidence collection process to accommodate the possibilities of wireless technologies. 802.11-based wireless technologies in particular pose an issue to the collection of electronic evidence, as devices that appear isolated may be wirelessly accessed during the collection phase, leading to after-seizure communications and a tampering of evidence in custody. Whilst forensic acquisition and analysis procedural guides are yet to discuss the acquisition of wireless devices, one of the core issues in collecting wireless devices is that there is no indication for the number or type of devices connected to a wireless network, should one exist in an area of interest. It is proposed that a series of forensic software tools be developed to aid in the detection, analysis and control of wireless networks that are in the process of being seized for forensic analysis. Through control of the wireless medium, information regarding connected devices may be gathered and methods to prevent communication between devices during and after evidence seizure are also examined.
Tool Support for BPEL Verification in ActiveBPEL Engine
Authors: Yi Qian, Yuming Xu, Zheng Wang, Geguang Pu, Huibiao Zhu, Chao Cai
Venue: Proceedings of the 2007 Australian Software Engineering Conference (2007)

The BPEL is designed for integrating and orches- trating web services and it provides the profound so- lution to model business process relying on web ser- vice platform. ActiveBPEL is a commercial-grade open source implementation engine for BPEL. In this pa- per, we describe the work on tool support for the BPEL verification in ActiveBPEL. We implement the algo- rithm of the mapping from BPEL to Timed Automata, and integrate it into the ActiveBPEL. By using model checker Uppaal engine, ActiveBPEL is enhanced and can verify the BPEL properties, such as deadlock and reachability. Moreover, those timed properties of BPEL specification can be checked in our framework as well. Some case studies are presented to show the usage of verification functionality in ActiveBPEL.
COMNET III: a network simulation laboratory environment for a course in communications networks
Authors: S. P. Ahuja
Venue: Proceedings of the 28th Annual Frontiers in Education - Volume 03 (1998)

COMNET III is a performance analysis tool for communications networks. It is used to model networks, their control algorithms and workload. COMNET III then simulates the operation of the network and provides measures of network performance. Students in data communications and networking courses can use COMNET III to model and simulate LANs, WANs and interconnections of various networks (Internets). Network simulations add a practical flavor to the course and enable students to observe the operation of an Internet comprising dissimilar networks and protocols.
Moving targets detection using sequential importance sampling
Authors: Gang Qian
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2001. on IEEE International Conference - Volume 03 (2001)

We present a new technique for detecting moving targets from image sequences captured by moving sensors. Feature points are detected and tracked through the image sequences. A validity vector is used to describe the consistency of the feature trajectories with sensor motion. By using the sequential importance sampling method, an approximation to the posterior distribution of the sensor motion and the validity vector is derived and the feature points belonging to the moving target are then segmented out. Real image examples are included.
An elliptic singularly perturbed problem with two parameters I: Solution decomposition
Authors: Lj. Teofanov, H. -G. Roos
Venue: Journal of Computational and Applied Mathematics (2007)

In this paper we consider a singularly perturbed elliptic problem with two small parameters posed on the unit square. Its solution may have exponential, parabolic and corner layers. We give a decomposition of the solution into regular and layer components and derive pointwise bounds on the components and their derivatives. The estimates are obtained by the analysis of appropriate problems on unbounded domains.
RFID Supplement for Mobile-Based Life Log System
Authors: Atsunori Minamikawa, Nobuhide Kotsuka, Masaru Honjo, Daisuke Morikawa, Satoshi Nishiyama, Masayoshi Ohashi
Venue: Proceedings of the 2007 International Symposium on Applications and the Internet Workshops (2007)

In this paper, we present a novel life log system, Life Pod, which collects user's activities by a mobile phone in the real world, and displays them in a blog like style. Engaging sensors installed in mobile phone and information attached to objects, users can easily record their daily activity anytime, anywhere. Implementation of RFID system to Life Pod also improves capturing information of real space.
Can pseudonymity really guarantee privacy?
Authors: Josyula R. Rao, Pankaj Rohatgi
Venue: Proceedings of the 9th conference on USENIX Security Symposium - Volume 9 (2000)

One of the core challenges facing the Internet today is the problem of ensuring privacy for its users. It is believed that mechanisms such as anonymity and pseudonymity are essential building blocks in formulating solutions to address these challenges and considerable effort has been devoted towards realizing these primitives in practice. The focus of this effort, however, has mostly been on hiding explicit identify information (such as source addresses) by employing a combination of anonymizing proxies, cryptographic techniques to distribute trust among them and traffic shaping techniques to defeat traffic analysis. We claim that such approaches ignore a significant amount of identifying information about the source that leaks from the contents of web traffic itself. In this paper, we demonstrate the significance and value of such information by showing how techniques from linguistics and stylometry can use this information to compromise pseudonymity in several important settings. We discuss the severity of this problem and suggest possible countermeasures.
Semantic model-driven architecting of service-based software systems
Authors: Claus Pahl
Venue: Information and Software Technology (2007)

Model-driven development is a software development framework that emphasises model-based abstraction and automated code generation. Service-based software architectures benefit in particular from semantic, ontology-based modelling. We present ontology-based transformation and reasoning techniques for layered semantic service architecture modelling. Integrated ontological layers support abstract domain modelling, architectural design, and interoperability aspects. Ontologies are beneficial due to their potential to formally define models, to allow reasoning about semantic models, and to automate transformations at all layers. Ontologies are suitable in particular for the Web Services platform due to their ubiquity within the Semantic Web and their application to support semantic Web services.
A Novel Photonic Container Switched Architecture and Scheduler to Design the Core Transport Network
Authors: Preetam Ghosh, Kalyan Basu, Sajal Das
Venue: IEEE Transactions on Computers (2007)

The ever-growing demand of network capacity has resulted in the inception of Optical Burst Switching (OBS), offering alloptical transmission, high-speed data rates, and format-transparent switching. However, the current OBS architecture is very complex, requiring costly fiber delay lines and quality-of-service (QoS) management techniques. In this paper, we propose a new OBS architecture based on photonic container switching to be deployed in the core network. We show that our architecture will solve most of the complexities of existing OBS mechanisms and, in fact, will make the core an all-optical zero-packet-loss network that will also guarantee equal QoS to all of the users. The packets are actually packed in fixed-size containers, which will be converted into an optical burst and transmitted through the network. Obviously, a major issue to solve in our architecture is the scheduler design that ensures zero packet loss and no optical-to-electrical switchings in the intermediate nodes. We devise a divide-and-conquer solution for the scheduler design problem and present some efficient algorithms for the same. We also analyze the performance of our algorithms under varying traffic conditions and network topologies to ascertain their efficiency and robustness.
Estimation of chirp signals by MCMC
Authors: Chung-Chieh Lin
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 01 (2000)

This paper considers the problem of parameter estimation of chirp signals by using the Bayesian methodology. The concept of "mirror points" for constant-amplitude chirp signals is introduced, and its effect on the overall multicomponent chirp parameter estimation performance assessed. By combining the chirpogram with a Markov chain Monte Carlo (MCMC) technique, it is shown that accurate estimates can be obtained for signals comprising many chirps. Simulation results demonstrate that the parameter estimates are in agreement with the CRLB for SNRs as low as 2 dB.
Just fast keying in the pi calculus
Authors: Martín Abadi, Bruno Blanchet, Cédric Fournet
Venue: ACM Transactions on Information and System Security (TISSEC) (2007)

JFK is a recent, attractive protocol for fast key establishment as part of securing IP communication. In this paper, we formally analyze this protocol in the applied pi calculus (partly in terms of observational equivalences and partly with the assistance of an automatic protocol verifier). We treat JFK's core security properties and also other properties that are rarely articulated and rigorously studied, such as plausible deniability and resistance to denial-of-service attacks. In the course of this analysis, we found some ambiguities and minor problems, such as limitations in identity protection, but we mostly obtain positive results about JFK. For this purpose, we develop ideas and techniques that should be more generally useful in the specification and verification of security protocols.
Enhanced Video Mosaicing using Camera Motion Properties
Authors: Pulkit Parikh, C. V. Jawahar
Venue: Proceedings of the IEEE Workshop on Motion and Video Computing (2007)

We propose a video mosaicing scheme which exploits the motion information, implicitly available in the video. The information about the camera motion is propagated to the homographies used for mosaicing. While some of the recent approaches make use of the information stemming from non-overlapping pairs of frames, the smoothness of the camera motion has gone largely under-capitalized. We present a technique which exploits this useful cue for refining homographies. Moreover, a generic framework which exploits the camera motion model, to relate homographies in a video, is also proposed. The analysis and results of the proposed algorithms demonstrate significant promise, in terms of accuracy and robustness.
Mining Workspace Updates in CVS
Authors: Thomas Zimmermann
Venue: Proceedings of the 29th International Conference on Software Engineering Workshops (2007)

The version control archive CVS records not only all changes in a project but also activity data such as when developers create or update their workspaces. Furthermore, CVS records when it has to integrate changes because of parallel development. In this paper, we analyze the CVS activity data of four large open-source projects GCC, JBOSS, JEDIT, and PYTHON to investigate parallel development: What is the degree of parallel development? How frequently do conflicts occur during updates and how are they resolved? How do we identify changes that contain integrations?
Context-dependent units for vocabulary-independent Spanish speech recognition
Authors: L. Villarrubia, L. H. Gomez, J. M. Elvira, J. C. Torrecilla
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1996. on Conference Proceedings., 1996 IEEE International Conference - Volume 01 (1996)

One of the most important issues in large-vocabulary speech recognition systems is the vocabulary-independence. In order to achieve this goal, modeling of vocabulary words by subwords units is mandatory. This paper studies the use of different subword units, comparing context-independent and context-dependent units (biphones, triphones and artificially generated triphones). From the experimental results we conclude the enormous importance of context dependence units and the good behaviour of biphone units compared to triphones for Spanish speech recognition considering the database limitations and the hardware restrictions in real systems. In order to consider the most important contextual effects in Castilian speech recognition we propose a new and simple approach based on the use of left and right-side biphones. Recognition results of 91.03% correct for vocabulary dependent data (448 surnames), and 89.6% correct for vocabulary independent data (955 surnames), using only 467 senones and 4 mixtures per state, on real telephone speech and speaker independent data are reported.
Personal recognition based on an image of the palmar surface of the hand
Authors: Tadej Savič, Nikola Pavešić
Venue: Pattern Recognition (2007)

This paper describes the design and development of a multimodal biometric personal recognition system based on features extracted from a set of 14 geometrical parameters of the hand, the palmprint, four digitprints, and four fingerprints. The features are extracted from a single high-resolution gray-scale image of the palmar surface of the hand using the linear discriminant analysis (LDA) appearance-based feature-extraction approach. The information contained in the extracted features is combined at the matching-score level. The resolutions of the palmprint, digitprint and fingerprint sub-images, the similarity/dissimilarity measures, the matching-score normalization technique, and the fusion rule at the matching-score level, which optimize the system performance, were determined experimentally. The biometric system, when using a system configuration with optimum parameters, showed an average equal error rate (EER) of 0.0005%, which makes it sufficiently accurate for use in high-security biometric systems.