ppxscal/embedding_network huggingface dataset:
Media-Driven Dynamic Scene Adaptation
Authors: B. Pellan, C. Concolato
Venue: Proceedings of the Eight International Workshop on Image Analysis for Multimedia Interactive Services (2007)

This paper presents a method to complement existing video, audio and image adaptation techniques in order to improve the perceived quality of interactive richmedia applications in streaming scenarios. This approach consists in dynamically adapting multimedia services at the presentation level according to medialevel adaptation decisions. First, an enhanced decision-taking engine decides on the best presentation form based on author constraints. Then, presentation updates dynamically modify the user display according to fluctuating environment constraints. A fine-grain control of the synchronization of these updates with adapted media streams is used to enable seamless switching of media bitstreams with different coding (transcoding) or switching to media streams with different modality (transmoding). This paper finally describes an application test-bed using MPEG-4 and MPEG-21 to implement the proposed adaptation approach and illustrates the user experience improvement.
A low probability of intercept signal detection receiver using quadrature mirror filter bank trees
Authors: T. C. Farrell
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1996. on Conference Proceedings., 1996 IEEE International Conference - Volume 03 (1996)

This paper describes a new type of spread spectrum intercept receiver. The receiver uses orthogonal wavelet techniques and a Quadrature Mirror Filter (QMF) bank tree to decompose a waveform into components representing the energy in rectangular "tiles" in the time frequency plane. By simultaneously examining multiple layers of the tree, the dimensions of concentrations of energy can be estimated with a higher resolution than is normally associated with linear transform techniques. This allows detection and feature extraction even when the interceptor has little knowledge of specific parameters of the signal being detected. For example, no prior knowledge of channelization or time segmentation is assumed. In addition, the receiver can intercept and distinguish between multiple signals.
An efficient solution method for relaxed variants of the nesting problem
Authors: Benny K. Nielsen
Venue: Proceedings of the thirteenth Australasian symposium on Theory of computing - Volume 65 (2007)

Given a set of irregular shapes, the strip nesting problem is the problem of packing the shapes within a rectangular strip of material such that the strip length is minimized, or equivalently the utilization of material is maximized. If the packing found is to be repeated, e.g., on a roll of fabric or a coil of metal, then the separation between repeats is going to be a straight line. This constraint can be relaxed by only requiring that the packing produced can be repeated without overlap. Instead of minimizing strip length one minimizes the periodicity of these repeats. We describe how to extend a previously published solution method (Egeblad, Nielsen & Odgaard 2006) for the nesting problem such that it can also handle the relaxation above. Furthermore, we examine the potential of the relaxed variant of the strip packing problem by making computational experiments on a set of benchmark instances from the garment industry. These experiments show that considerable improvements in utilization can be obtained.
Heuristics for Improving Cryptographic Key Assignment in a Hierarchy
Authors: Anne V. D. M. Kayem, Patrick Martin, Selim G. Akl
Venue: Proceedings of the 21st International Conference on Advanced Information Networking and Applications Workshops - Volume 01 (2007)

In hierarchical distributed systems, shared data access can be controlled by assigning user groups single cryptographic keys that allow high level users derive low level keys, but not the reverse. The drawback in this approach to key management is the requirement of replacing keys throughout the entire hierarchy whenever group membership changes, to preserve security. This paper presents two algorithms, based on a precedence tree graph model, that use a distance-based heuristic to minimize the cost of key assignment and replacement, respectively. In the average case, only the keys belonging to the group affected and its sub-tree are replaced. A complexity analysis and experimental results indicating performance improvements demonstrate the feasibility of the proposed algorithms.
Optimizing Multicast Performance in Large-Scale WLANs
Authors: Ai Chen, Dongwook Lee, Prasun Sinha
Venue: Proceedings of the 27th International Conference on Distributed Computing Systems (2007)

Support for efficient multicasting in WLANs can enable new services such as streaming TV channels, radio channels, and visitor's information. With increasing deployments of large-scale WLANs, such services can have a significant impact. However, for a solution to be viable, the mutlicast services must minimally impact the existing unicast services which are currently the core services offered by most WLANs. This paper focuses on three objective functions motivated by different revenue functions and network scenarios: maximizing the number of users (MNU), balancing the load among APs (BLA), and minimizing the load of APs (MLA). We show that these problems are NP-hard and present centralized approximation algorithms and distributed approaches to solve them. Using simulations we evaluate the performance of these algorithms. We observe that the number of users can be increased by up to 36:9%, and the maximum AP load and the total load can be reduced by up to 52:9% and 31:1%, respectively.
Behavioural Types for Service Integration: Achievements and Challenges
Authors: Antonio Brogi, Carlos Canal, Ernesto Pimentel
Venue: Electronic Notes in Theoretical Computer Science (ENTCS) (2007)

Increasing attention is being paid to the development of so-called behavioural types as a means to formally address the problem of ensuring the correct interoperation of software components as well as of Web services. The objective of this paper is to provide an insightful synthesis of the state-of-the-art in this area, both to summarise the main results achieved and to point out some important challenges to be faced for a real impact of these ideas in the software world.
REMAP-experiments with speech recognition
Authors: Y. Konig
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1996. on Conference Proceedings., 1996 IEEE International Conference - Volume 06 (1996)

We present experimental and theoretical results using a framework for training and modeling continuous speech recognition systems based on the theoretically optimal maximum a posteriori (MAP) criterion. This is in contrast to most state-of-the-art systems which are trained according to a maximum likelihood (ML) criterion. Although the algorithm is quite general, we applied it to a particular form of hybrid system combining hidden Markov models (HMMs) and artificial neural networks (ANNs) in which the ANN targets and weights are iteratively reestimated to guarantee the increase of the posterior probability of the correct model, hence actually minimizing the error rate. More specifically, this training approach is applied to a transition-based model that uses local conditional transition probabilities (i.e. the posterior probability of the current state given the current acoustic vector and the previous state) to estimate the posterior probabilities of sentences. Experimental results on isolated and continuous speech recognition tasks show an increase in the estimates of posterior probabilities of the correct sentences after training, and significant decreases in error rates in comparison to a baseline system.
Wrong Again!
Authors: Francis Sullivan
Venue: Computing in Science and Engineering (2007)

Contributing editor Francis Sullivan explores the issue of self-checking algorithms.
A Model Supporting Business Continuity Auditing and Planning in Information Systems
Authors: Emmanuele Zambon, Damiano Bolzoni, Sandro Etalle, Marco Salvato
Venue: Proceedings of the Second International Conference on Internet Monitoring and Protection (2007)

One of the main tasks of IT business continuity planning (BCP) is to guarantee that incidents affecting the IT infrastructure do not affect the availability of IT-dependent business processes beyond a given acceptable extent. Carrying out BCP of information systems is particularly challenging, because it has to take into consideration the numerous interdependencies between the IT assets typically present in an organization. In this paper we present a model and a tool supporting BCP auditing by allowing IT personnel to estimate and validate the Recovery Time Objectives (to be) set on the various processes of the organization. Our tool can be integrated in COBIT-based risk assessment applications. Finally, we argue that our tool can be particularly useful for the dynamic auditing of the BCP.
Analysis of spectral regrowth of weakly nonlinear power amplifiers
Authors: G. T. Zhou
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 05 (2000)

Power amplifiers (PAs) are important components in a wireless communications system. Linearity and efficiency are two desirable but conflicting requirements of a PA. All PAs exhibit varying degrees of nonlinearity which causes spectral regrowth and adjacent channel interference. Based on the behavior model of the PA and statistics of the input, it is possible to infer spectral regrowth in the output. Existing analytical results on spectral regrowth assume that the input is Gaussian, which is unrealistic for many digital communications signals. We derive a closed form expression between the covariance function (and hence the power spectrum) of the output and statistics of the input, based on a polynomial behavior model of the PA, without assuming that the input is Gaussian. Such analytical results are useful in finding optimal operating conditions of the PA so that maximum efficiency is achieved without violating the out-of-band emission requirement.
On The Chromatic Number Of Pentagon-Free Graphs Of Large Minimum Degree
Authors: Carsten Thomassen
Venue: Combinatorica (2007)

We prove that, for each fixed real number c > 0, the pentagon-free graphs of minimum degree at least cn (where n is the number of vertices) have bounded chromatic number. This problem was raised by Erd&#x0151;s and Simonovits in 1973. A similar result holds for any other fixed odd cycle, except the triangle for which there is no such result for c<1/3.
Optimal multiframe detection and tracking in digital image sequences
Authors: M. G. S. Bruno
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 05 (2000)

We present a Bayesian algorithm for optimal multiframe detection and tracking of small extended targets in two-dimensional (2D) finite resolution images. The algorithm integrates detection and tracking into a single framework using as data a sequence of cluttered sensor snapshots. Performance studies using Monte Carlo simulations show substantial improvements when the proposed Bayes tracker is compared to the association of a correlation filter and a linearized Kalman-Bucy filter. Likewise, there are significant detection performance gains of up to 6 dB in peak signal-to-noise ratio (PSNR) when the multiframe Bayes detector is compared to a single frame likelihood ratio test (LRT) detector.
Toward Building a Multi-level Robust Intrusion Detection Architecture for Distributed Mobile Networks
Authors: Geethapriya Thamilarasu, Ramalingam Sridhar
Venue: Proceedings of the 27th International Conference on Distributed Computing Systems Workshops (2007)

A robust intrusion detection architecture for a distributed wireless mobile network is of significant importance as it is necessary to secure these networks against malicious attacks and sustain availability of services to various applications. In this paper, we examine the limitations of a layered approach to security in mobile networks. We consider a detection framework that encompasses multiple layers of the node's protocol stack using cross-layer communications. We discuss the functional advantages of the parameter interactions in intrusion detection, with regard to a few parameters. We present the metrics that characterize an efficient detection system and analyze the benefits of a multi-level intrusion detection architecture.
An MS-DOS file system for UNIX
Authors: Alessandro Forin, Gerald R. Malan
Venue: Proceedings of the USENIX Winter 1994 Technical Conference on USENIX Winter 1994 Technical Conference (1994)

We have written DosFs, a new file system for UNIX that uses MS-DOS data structures for permanent storage. DosFs can be used anywhere a traditional UNIX file system can be used, and it can mount disks written by MS-DOS as regular UNIX partitions. DosFs can be used as the root partition, and exported by an NFS server. Our motivation for this work was efficient disk space utilization; DosFs provides from 30% to 80% better disk utilization than the 4.3 BSD Fast File System (FFS). In addition, we found that the disk block allocation algorithm used by DosFs lets us exploit large contiguous disk operations, providing a five-fold improvement over FFS for uncached operations. To the best of our knowledge, this is the first file system implementation that allows the user to specify the logical block size at mount time. A user can mount the same fileystem with a larger block size when file accesses tend to be sequential and a smaller one when they tend to be scattered. The MS-DOS structures were designed for a single-user system and do not support access control. We solved this problem with simple extensions that are backward-compatible with MS-DOS.
Discriminating image senses by clustering with multimodal features
Authors: Nicolas Loeff, Cecilia Ovesdotter Alm, David A. Forsyth
Venue: Proceedings of the COLING/ACL on Main conference poster sessions (2006)

We discuss Image Sense Discrimination (ISD), and apply a method based on spectral clustering, using multimodal features from the image and text of the embedding web page. We evaluate our method on a new data set of annotated web images, retrieved with ambiguous query terms. Experiments investigate different levels of sense granularity, as well as the impact of text and image features, and global versus local text features.
Improvement of MBSD by scaling noise masking threshold and correlation analysis with MOS difference instead of MOS
Authors: Wonho Yang
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1999. on 1999 IEEE International Conference - Volume 02 (1999)

The modified bark spectral distortion (MBSD) used for an objective speech quality measure, was presented previously. The MBSD measure estimates speech distortion in the loudness domain taking into account the noise masking threshold in order to include only audible distortions in the calculation of the distortion measure. Preliminary simulation results have shown improvement of the MBSD over the conventional BSD. The performance of the MBSD is improved by scaling noise masking threshold and comparing it to ITU-T Recommendation P.861 and MNB measures. Correlation analysis with MOS difference instead of MOS has been examined in order to evaluate objective speech quality measures.
Matrix algebraic selection of ARMA model order
Authors: K. Gerlach
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 01 (2000)

A matrix algebraic method of order selection is proposed for ARMA time series modeling for situations in which both inputs and outputs are observed in additive noise with known variances. Such situations include observational studies in which all observations-those of both inputs and outputs-are erred and controlled experiments in which outputs are observed with error while inputs are observed without error. The proposed method is based on the eigenvalue structure of the covariance matrices associated with the observed data and performs well for short data records at moderate SNRs.
A visual probe localization and calibration system for cost-effective computer-aided 3D ultrasound
Authors: Aziah Ali, Rajasvaran Logeswaran
Venue: Computers in Biology and Medicine (2007)

The 3D ultrasound systems produce much better reproductions than 2D ultrasound, but their prohibitively high cost deprives many less affluent organization this benefit. This paper proposes using the conventional 2D ultrasound equipment readily available in most hospitals, along with a single conventional digital camera, to construct 3D ultrasound images. The proposed system applies computer vision to extract position information of the ultrasound probe while the scanning takes place. The probe, calibrated in order to calculate the offset of the ultrasound scan from the position of the marker attached to it, is used to scan a number of geometrical objects. Using the proposed system, the 3D volumes of the objects were successfully reconstructed. The system was tested in clinical situations where human body parts were scanned. The results presented, and confirmed by medical staff, are very encouraging for cost-effective implementation of computer-aided 3D ultrasound using a simple setup with 2D ultrasound equipment and a conventional digital camera.
Performance Issues of a Superscalar Microprocessor
Authors: Steven Wallace, Nader Bagherzadeh
Venue: Proceedings of the 1994 International Conference on Parallel Processing - Volume 01 (1994)

Cache, dynamic scheduling, bypassing, branch prediction, and fetch efficiency are primary issues concerning performance of a superscalar microprocessor. This paper considers all these issues and shows their impact on performance by running our simulator on seventeen different programs. Our approach in handling branch prediction is shown to significantly decrease the bad branch penalty. Furthermore, results show that the average instruction fetch places an upper bound on speedup and is the most critical factor in determining overall performance. Its performance impact is greater than all other factors combined.
A collaborative multimedia, Web-based electronics course: project description and survey
Authors: S. Villareal
Venue: Proceedings of the 26th Annual Frontiers in Education - Volume 01 (1996)

Our interest, development and use of multimedia educational materials has proceeded mainly along two parallel paths. One path has emphasized computer-animated simulations, which are animations controlled by parameters set by the student. This approach enhances student learning by providing realistic visual feedback of qualitatively correct results. The second path emphasizes virtual instrumentation, which uses graphics and video-clip demonstrations via the Internet. This approach increases students' learning efficiency by providing them with simulated experiences with laboratory equipment and procedures before, during and after conventional laboratory activities. One major obstacle to any kind of materials development, especially multimedia development, is the issue of resources. To most effectively combine our existing materials, and to leverage limited resources, we have established a framework for a coalition of technology programs with similar goals and interests. A brief interest survey, sent to approximately 240 members of the Texas Junior College Teachers Association, shows that 30% of the respondents are already involved in multimedia development, 54% have Internet connectivity, and 77% are interested in participating in our collaborative efforts.
WTMR--A New Fault Tolerance Technique for Wireless and Mobile Computing Systems
Authors: Sarmistha Neogy
Venue: Proceedings of the 11th IEEE International Workshop on Future Trends of Distributed Computing Systems (2007)

During the last decade, much research has been done to evolve cost-effective techniques for fault tolerance of applications running on static distributed systems. With the advent of technology, wireless systems emerged by the end of the last decade, and received considerable attention as useful environments for mobile distributed systems. The requirements for designing fault tolerant techniques for the mobile computing systems have also come to the front. The objective of this paper is to study, analyse the effectiveness of (i) Triple Modular Redundancy (TMR) technique and (ii) checkpoint and recovery technique that may be used by wireless/mobile systems for tolerating faults. A WirelessTMR-(WTMR) Checkpointing technique is proposed in the paper that uses checkpointing technique to add fault tolerance to a fault tolerant TMR node in wireless system.
New techniques for geographic routing
Authors: Barbara Liskov
Venue:  (2006)

As wireless sensor networks continue to grow in size, we are faced with the prospect of emerging wireless networks with hundreds or thousands of nodes. Geographic routing algorithms are a promising alternative to tradition ad hoc routing algorithms in this new domain for point-to-point routing, but deployments of such algorithms are currently uncommon because of some practical difficulties. This dissertation explores techniques that address two major issues in the deployment of geographic routing algorithms: (i) the costs associated with distributed planarization and (ii) the unavailability of location information. We present and evaluate two new algorithms for geographic routing: Greedy Distributed Spanning Tree Routing (GDSTR) and Greedy Embedding Spring Coordinates (GSpring). Unlike previous geographic routing algorithms which require the planarization of the network connectivity graph, GDSTR switches to routing on a spanning tree instead of a planar graph when packets end up at dead ends during greedy forwarding. To choose a direction on the tree that is most likely to make progress towards the destination, each GDSTR node maintains a summary of the area covered by the subtree below each of its tree neighbors using convex hulls. This distributed data structure is called a hull tree. GDSTR not only requires an order of magnitude less bandwidth to maintain these hull trees than CLDP, the only distributed planarization algorithm that is known to work with practical radio networks, it often achieves better routing performance than previous planarization-based geographic routing algorithms. GSpring is a new virtual coordinate assignment algorithm that derives good coordinates for geographic routing when location information is not available. Starting from a set of initial coordinates for a set of elected perimeter nodes, GSpring uses a modified spring relaxation algorithm to incrementally adjust virtual coordinates to increase the convexity of voids in the virtual routing topology. This reduces the probability that packets will end up in dead ends during greedy forwarding, and improves the routing performance of existing geographic routing algorithms. The coordinates derived by GSpring yield comparable routing performance to that for actual physical coordinates and significantly better performance than that for NoGeo, the best existing algorithm for deriving virtual coordinates for geographic routing. Furthermore, GSpring is the first known algorithm that is able to derive coordinates that achieve better geographic routing performance than actual physical coordinates for networks with obstacles. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)