ppxscal/embedding_network huggingface dataset:
Comparing Countermeasures against Interrupt-Related Covert Channels in an Information-Theoretic Framework
Authors: Heiko Mantel, Henning Sudbrock
Venue: Proceedings of the 20th IEEE Computer Security Foundations Symposium (2007)

Interrupt-driven communication with hardware devices can be exploited for establishing covert channels. In this article, we propose an information-theoretic framework for analyzing the bandwidth of such interrupt-related channels while taking aspects of noise into account. As countermeasures, we present mechanisms that are already implemented in some operating systems, though for a different purpose. Based on our formal framework, the effectiveness of the mechanisms is evaluated. Despite the large body of work on covert channels, this is the first comprehensive account of interrupt-related covert channel analysis and mitigation.
Enabling tracing Of long-running multithreaded programs via dynamic execution reduction
Authors: Sriraman Tallam, Chen Tian, Rajiv Gupta, Xiangyu Zhang
Venue: Proceedings of the 2007 international symposium on Software testing and analysis (2007)

Debugging long running multithreaded programs is a very challenging problem when using tracing-based analyses. Since such programs are non-deterministic, reproducing the bug is non-trivial and generating and inspecting traces for long running programs can be prohibitively expensive. We propose a framework in which, to overcome the problem of bug reproducibility, a lightweight logging technique is used to log the events during the original execution. When a bug is encountered, it is reproduced using the generated log and during the replay, a fine-grained tracing technique is employed to collect control-flow/dependence traces that are then used to locate the root cause of the bug. In this paper, we address the key challenges resulting due to tracing, that is, the prohibitively high expense of collecting traces and the significant burden on the user who must examine the large amount of trace information to locate the bug in a long-running multithreaded program. These challenges are addressed through execution reduction that realizes a combination of logging and tracing such that traces collected contain only the execution information from those regions of threads that are relevant to the fault. This approach is highly effective because we observe that for long running multithreaded programs, many threads that execute are irrelevant to the fault. Hence, these threads need not be replayed and traced when trying to reproduce the bug. We develop a novel lightweight scheme that identifies such threads by observing all the interthread data dependences and removes their execution footprint in the replay run. In addition, we identify regions of thread executions that need not be replayed or, if they must be replayed, we determine if they need not be traced. Following execution reduction, the replayed execution takes lesser time to run and it produces a much smaller trace than the original execution. Thus, the cost of collecting traces and the effort of examining the traces to locate the fault are greatly reduced.
Multitarget detection/tracking based on hidden Markov models
Authors: M. Nicoli
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 05 (2000)

In several remote sensing applications, multitarget detection/tracking (D/T) of the backscattered wavefields is a very demanding task. Wavefield signals, sampled by an array of sensors, can be described by an hidden Markov model (HMM). As a consequence, the time of delay (TOD) profiles for each of the wavefield (or target) can be estimated by any of the known methods for state-sequence estimation such as the Viterbi (VA) and the backward/forward (BFA) algorithms. Some assumptions, that arise in the wavefield separation problem, allow one to include some additional constraints that preserve the target/tracker association. When an improved resolution is required, the choice of the multitarget Viterbi algorithm (MVA) is mandatory even if its complexity increases exponentially.
Frames and orthonormal bases for variable windowed Fourier transforms
Authors: Neng-Tsann Ueng
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1996. on Conference Proceedings., 1996 IEEE International Conference - Volume 05 (1996)

The Gabor transform (or the windowed Fourier transform) is a widely used tool in signal processing. We generalize the windowed Fourier transform to the variable-windowed Fourier transform. This generalization brings the Gabor transform and the wavelet transform under the same framework. Using frame theory we characterize frames and orthonormal bases for the variable windowed Fourier series (VWFS). These characterizations are formulated explicitly in terms of window functions. Therefore they can serve as guidelines for designing windows for the VWFS. We introduce the notion of "complete orthogonal support" and, with the help of this notion, we construct a class of orthonormal VWFS bases for L/sup 2/(R/sup +/).
Joint MPEG-2 coding for multi-program broadcasting of pre-recorded video
Authors: I. Koo
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1999. on 1999 IEEE International Conference - Volume 04 (1999)

We developed a cost-effective operational system suitable for digital TV, video on demand, and high definition TV broadcast over satellite networks with limited bandwidth. This MPEG-2 based system is easy to implement and allows the joint video coding of multiple video programs. Compared to present broadcast operations and for the same level of picture quality, our system greatly increases the number of video streams transmitted in each channel. As a result, either a large number of transponders can be freed up to carry real-time broadcasting or the level of the transmitted picture quality can be significantly increased, By switching from tape storage to video server technology, the need for numerous (expensive) playback VTR systems at the headend is eliminated. In addition, the majority of the complete MPEG-2 encoders are replaced by much less complex MPEG-2 transcoders. All this means significant savings for the broadcast stations. In addition to the gain in bandwidth and the reduction in cost, our system speeds up the encoding process by six fold.
Cone constrained adaptive algorithms and multiple access interference cancellation
Authors: M. I. Doroslovacki
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1999. on 1999 IEEE International Conference - Volume 03 (1999)

A parameterization of the cone around a given vector in N-dimensional vector space is derived. Vectors obtained by changing the parameter values can not escape the cone. The constraint is useful when it is known that an optimal vector of filter coefficients is close in direction with the given vector. Adaptive filtering algorithms that use the steepest descent method and stochastic gradient approximation are developed for the case of filter coefficients constrained in the cone. There is no need for monitoring the constraint since it is always satisfied by the construction. Two optimization criteria are explicitly considered: the least mean square and constant modulus. The cone constrained constant modulus algorithm (CMA) is applied to the problem of user detection in a synchronous direct sequence code division multiple access system. Its convergence is compared with the plain CMA and back projection CMA. Under severe conditions the cone constrained CMA is the only one which locks to the desired user.
A Case Study: Applying Lyra in Modeling S60 Camera Functionality
Authors: Jukka Honkola, Sari Leppanen, Pasi Rinne-Rahkola, Martti Soderlund, Markku Turunen, Kimmo Varpaaniemi
Venue: Proceedings of the 14th Annual IEEE International Conference and Workshops on the Engineering of Computer-Based Systems (2007)

We present an application of a modeling method for distributed systems to a case study of mobile phone camera functionality based on an existing implementation. The modeling method, Lyra, utilizes formal definitions, in this case UML2 state machines, for behavior. We observe the industrial application of the models, for instance modeling conventions and tool support needed to enable it, and the application cases of model based testing and illustration of system properties.
An application experience with an implicitly parallel composition language
Authors: R. Jagannathan, Chris Dodd
Venue: Proceedings of the USENIX 1994 Very High Level Languages Symposium Proceedings on USENIX 1994 Very High Level Languages Symposium Proceedings (1994)

We describe our experiences with a very high-level parallel composition language (called GLU) that enables rapid construction of parallel applications using sequential building blocks (extracted from existing sequential applications) and their execution on diverse parallel computer systems. GLU is sufficiently rich to succinctly express different forms of parallelism -- from function parallelism to data parallelism and from pipeline parallelism to tree parallelism. We show by example how a typical sequential application can be converted to a parallel one in GLU and executed on different parallel systems. We also show how GLU has been used to convert two widely used, sequentially written, inherently parallel workstation applications -- the make utility and a raytracing system -- to parallel equivalents that can then be run much faster on a network of workstations.
Adoption of XP practices in the industry&mdash;A survey: Research Sections
Authors: Alexia N. Bowers, Raghvinder S. Sangwan, Colin J. Neill
Venue: Software Process: Improvement and Practice (2007)

Agile software development has recently become popular in the software industry. The methodologies in the Agile family are considered to be based on best practices. The most popular approach, Extreme Programming (XP), recommends certain best practices during the requirements gathering, implementation and testing phases of software development. In this paper, the authors analyze the best practices according to data from recent case studies and survey studies to see if and how they are followed. Metaphor was the least used practice, while unit testing was one of the most popular. Most of the practices varied across studies and projects. Agile software development is evolutionary in nature, so customizing the practices is still well within its sounds. Copyright &copy; 2007 John Wiley & Sons, Ltd.
The Architecture-Requirements Interaction
Authors: James A. Miller, Nazim H. Madhavji
Venue: Proceedings of the Sixth Working IEEE/IFIP Conference on Software Architecture (2007)

The interaction between software architecture (SA) and requirements engineering (RE) processes is generating interest within the research community. We explored the role of SA documentation in requirements decision-making. This paper describes the findings from this study.
Separation of cochannel signals using the parametric constant modulus algorithm
Authors: A. Rao
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1996. on Conference Proceedings., 1996 IEEE International Conference - Volume 05 (1996)

In an earlier paper, Rao and Kumaresan (see Proc. of the 29-th Asilomar Conf. on Sig., Sys., and Comp., 1995) proposed a new algorithm, called the parametric constant modulus algorithm (PCMA) to demodulate noiseless, synthetic as well as real-world, cochannel FM signals. They extend the PCMA to develop two new procedures. The first one addresses the problem of reserving two closely spaced noisy sinewaves (from a short data record). The second algorithm is applied to estimate the phase parameters of two superimposed noisy chirp signals; both algorithm's performance are compared with the Cramer-Rao bounds. The techniques described are of interest in wireless/military communications in the context of carrier frequency and Doppler estimation.
Automatic classification of QAM signals by neural networks
Authors: S. Taira
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 200. on IEEE International Conference - Volume 02 (2001)

In this paper, automatic classification of QAM signals including 64-state QAM and 256-state QAM is discussed. Three layer neural networks whose input data are the histogram distribution of instantaneous amplitude at symbol points are used for the classification. The evaluation of the classification performance is carried out for both cases in which the synchronization of symbol timing is assured at the receiver and not assured. Good classification results are obtained by the computer simulations at SNR/spl ges/10 dB. The influence of the number of symbol points which are used for the calculation of the histogram is also discussed. 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
Topology-Controlled Volume Rendering
Authors: Gunther H. Weber, Scott E. Dillard Hamish Carr, Valerio Pascucci, Bernd Hamann
Venue: IEEE Transactions on Visualization and Computer Graphics (2007)

Topology provides a foundation for the development of mathematically sound tools for processing and exploration of scalar fields. Existing topology-based methods can be used to identify interesting features in volumetric data sets, to find seed sets for accelerated isosurface extraction, or to treat individual connected components as distinct entities for isosurfacing or interval volume rendering. We describe a framework for direct volume rendering based on segmenting a volume into regions of equivalent contour topology and applying separate transfer functions to each region. Each region corresponds to a branch of a hierarchical contour tree decomposition, and a separate transfer function can be defined for it. The novel contributions of our work are 1) a volume rendering framework and interface where a unique transfer function can be assigned to each subvolume corresponding to a branch of the contour tree, 2) a runtime method for adjusting data values to reflect contour tree simplifications, 3) an efficient way of mapping a spatial location into the contour tree to determine the applicable transfer function, and 4) an algorithm for hardware-accelerated direct volume rendering that visualizes the contour tree-based segmentation at interactive frame rates using graphics processing units (GPUs) that support loops and conditional branches in fragment programs.
Decision-Oriented Modeling of Product Line Architectures
Authors: Deepak Dhungana, Rick Rabiser, Paul Grunbacher
Venue: Proceedings of the Sixth Working IEEE/IFIP Conference on Software Architecture (2007)

Understanding and modeling architectural variability is fundamental in product line engineering. Various extensions have been proposed to architecture description languages (ADLs) to deal with variability. Although these extensions are useful, we argue in this paper that decisions need to be treated as first-class citizens for modeling architectural variability. Decisions that have to be taken by different stakeholders during product derivation are an essential source to understand the variability at different levels (e.g., features, architecture, and implementation). We outline a decision-oriented approach to variability modeling and illustrate it with an example from our ongoing research collaboration with Siemens VAI.
Enhanced e-Services through Partnerships--Increasing the Value of Public Infrastructure Investments
Authors: Lasse Berntzen
Venue: Proceedings of the First International Conference on the Digital Society (2007)

this paper presents a conceptual model for collaboration between government, individuals and voluntary organizations to provide innovative digital services to the public. The government provides the necessary infrastructure, application software and basic content, with the opportunity for individuals and voluntary organizations to provide additional content. This approach makes it possible to deliver services of greater value to the public. Two Norwegian case examples are used to show the practical use of this conceptual model. The first case, "The Digital Inn", shows how the Norwegian National Archival Services use collaboration to enhance its service to genealogists. The second case describes "The Map Hostel", a project to better utilize geographic information systems by delivering new maps based on information collected by voluntary organizations and individuals.
On Circular Flows Of Graphs
Authors: Hong-Jian Lai, Rui Xu, Cun-Quan Zhang
Venue: Combinatorica (2007)

A sufficient condition for graphs with circular flow index less than 4 is found in this paper. In particular, we give a simple proof of a result obtained by Galluccio and Goddyn (Combinatorica, 2002), and obtain a larger family of such graphs.
A new scanning MEMS mirror
Authors: Z. F. Wang, W. Noell, M. Zickar, N. de Rooij, S. P. Lim
Venue: Microsystem Technologies (2007)

This paper introduces the development of a new MEMS-based optical mirror, which performs optical scanning function with discrete reflection angles in an out-of-plane configuration. The device was fabricated through Deep Reactive Ion Etching (DRIE) process on silicon-on-insulator (SOI) wafer, followed by assembly with two metalised glass dies. The optical mirrors can be tilted by electrostatic forces between the opposite electrodes on the SOI and glass dies. The most outstanding performance that can be expected from the device is the discrete and therefore, reliable tilting angle of the mirror, which is guaranteed by its unique mechanical structure and the electrostatically driven mechanism. In this paper, the working principle of the new MEMS mirror was presented, followed by the introduction of device design, mechanical simulation, microfabrication process, assembly solution, and some testing results. The potential application of this new MEMS mirror is for light beam scanning or optical sensing (detection).
Privtrans: automatically partitioning programs for privilege separation
Authors: David Brumley, Dawn Song
Venue: Proceedings of the 13th conference on USENIX Security Symposium - Volume 13 (2004)

Privilege separation partitions a single program into two parts: a privileged program called the monitor and an unprivileged program called the slave. All trust and privileges are relegated to the monitor, which results in a smaller and more easily secured trust base. Previously the privilege separation procedure, i.e., partitioning one program into the monitor and slave, was done by hand [18, 28]. We design techniques and develop a tool called Privtrans that allows us to automatically integrate privilege separation into source code, provided a few programmer annotations. For instance, our approach can automatically integrate the privilege separation previously done by hand in OpenSSH, while enjoying similar security benefits. Additionally, we propose optimization techniques that augment static analysis with dynamic information. Our optimization techniques reduce the number of expensive calls made by the slave to the monitor. We show Privtrans is effective by integrating privilege separation into several open-source applications.
Visual Modeling of Ontology Views for e-Sciences Using XSemantic Nets
Authors: R. Rajugan, Elizabeth Chang, Tharam S. Dillon
Venue: Proceedings of the Twentieth IEEE International Symposium on Computer-Based Medical Systems (2007)

Ontologies are the foundation of the Semantic Web (SW) and one of the keys necessary to its success. Conversely, e-Science domains are usually characterized by heterogeneous semistructured data models and formats. In recent years, building ontologies are gaining momentum in the e-Science domains to provide explanatory semantics in an agreed, yet shared encodings. Conversely, ontology views hold the promise of; (a) provide a manageable portion of a larger ontology for the localized applications and users, (b) enable precise extraction of sub-onlogies of a larger ontology that commits to the main ontology, (c) enable localized customization and usage of the portion of a larger ontology and (d) enable interoperability between large ontology bases and applications. Therefore, it is interesting to look at ontology views and their desired applications in the context of e-Sciences, as there exists no agreed upon standard, methodology or formalism to specify, define and materialize such ontology views. Thus, in this paper, we elaborate on our own research direction towards proposing a meaningful ontology view formalism and its associated semantics for the e- Science domain.
The Communication Complexity of Correlation
Authors: Prahladh Harsha, Rahul Jain, David McAllester, Jaikumar Radhakrishnan
Venue: Proceedings of the Twenty-Second Annual IEEE Conference on Computational Complexity (2007)

We examine the communication required for generating random variables remotely. One party Alice is given a distribution D, and she has to send a message to Bob, who is then required to generate a value with distribution exactly D. Alice and Bob are allowed to share random bits generated without the knowledge of D. There are two settings based on how the distribution D provided to Alice is chosen. If D is itself chosen randomly from some set (the set and distribution are known in advance) and we wish to minimize the expected communication in order for Alice to generate a value y, with distribution D, then we characterize the communication required in terms of the mutual information between the input to Alice and the output Bob is required to generate. If D is chosen from a set of distributions D, and we wish to devise a protocol so that the expected communication (the randomness comes from the shared random string and Alice's coin tosses) is small for each D \in¸ D, then we characterize the communication required in this case in terms of the channel capacity associated with the set D. Our proofs are based on an improved rejection sampling procedure that relates the relative entropy between two distributions to the communication complexity of generating one distribution from the other. As an application of these results, we derive a direct sum theorem in communication complexity that substantially improves the previous such result shown by Jain et al. [JRSb].
Visualization and Characterization of Stability Swings via GPS-Synchronized Data
Authors: George J. Cokkinides, A. P. Sakis Meliopoulos, George Stefopoulos, Ramiz Alaileh, Apurva Mohan
Venue: Proceedings of the 40th Annual Hawaii International Conference on System Sciences (2007)

This paper provides a methodology to characterize the accuracy of PMU data (GPS-synchronized) and the applicability of this data for monitoring system stability via visualization methods. GPS-synchronized equipment (PMUs) is in general higher precision equipment as compared to typical SCADA systems. Conceptually, PMU data are time tagged with precision better than 1 microsecond and magnitude accuracy that is better than 0.1%. This potential performance is not achieved in an actual field installation due to errors from instrumentation channels and system imbalances. Presently, PMU data precision from substation installed devices is practically unknown. On the other hand, specific applications of PMU data require specific accuracy of data. Applications vary from simple system monitoring to wide area protection and control to voltage instability prediction and transient stability monitoring. The paper focuses on the last application, i.e. transient stability monitoring. We propose an approach that is based on accurate evaluation of the system energy function (Lyapunov indirect method) and extraction of stability properties from the energy function. Specifically, we provide a methodology for determining the required data accuracy for the reliable real time estimation of the energy function. When the data meet these requirements, the estimated energy function can be visualized and animated providing a powerful visual tool for observing the transient stability or instability of the system.