ppxscal/embedding_network huggingface dataset:
Prescription-based error concealment technique for video transmission on error-prone channels
Authors: Wen-Nung Lie, Tom C. -I. Lin
Venue: Journal of Visual Communication and Image Representation (2007)

In this article, a prescription-based error concealment (PEC) technique, based on a three-stage (diagnosis, prescription, and remedy) process, is proposed for video transmission on error-prone channels. A prescription is meant to be the best error concealment scheme among several pre-chosen ones, which are evaluated at encoder side for each MB. The collection of prescriptions for each frame is compressed and transmitted through a reliable channel to provide flexible and better error-recovery performance at decoder side. Experimental results show that the proposed PEC method is capable of achieving a PSNR improvement of up to 1.5dB, with respect to the best single-mode scheme, when video bit rate and PER (packet error rate) are up to 512kbps and 20%, respectively, whereas only a small amount of overheads (i.e., the coded prescriptions) is generated for reliable transmission.
Localization by harmonic structure and its application to harmonic sound stream segregation
Authors: T. Nakatani
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1996. on Conference Proceedings., 1996 IEEE International Conference - Volume 02 (1996)

Sound stream segregation is essential for understanding auditory events in the real-world. In this paper, we present a new method for sound stream segregation using harmonic structure and localization, or direction, in the horizontal plane. The direction of the sound source is determined by using the harmonic structure extracted from binaural inputs. The fundamental frequency of each sound is then refined by using the direction of its source. This paper discusses how the effectiveness of the harmonic-based stream segregation system (HBSS) is improved by incorporating the new method and presents the binaural HBSS (Bi-HBSS). In particular, experimental results show that the Bi-HBSS reduces the spectrum distortions and the fundamental frequency errors, compared with the HBSS and with a direction-based stream segregation system.
A Monte Carlo framework to evaluate context based security policies in pervasive mobile environments
Authors: Carlos Sanchez, Le Gruenwald, Mauricio Sanchez
Venue: Proceedings of the 6th ACM international workshop on Data engineering for wireless and mobile access (2007)

A pervasive mobile computing environment is typically composed of multiple fixed and mobile entities that interact autonomously with each other with very little central control. Many of these interactions may occur between entities that have not interacted with each other previously. Conventional security models are inadequate for regulating access to data and services, especially when the identities of a dynamic and growing community of entities are not known in advance. In order to cope with this drawback, entities may rely on context data to make security and trust decisions. However, risk is introduced in this process due to the variability and uncertainty of context information. Moreover, by the time the decisions are made, the context data may have already changed and, in which case, the security decisions could become invalid. In this paper, we propose a Monte Carlo based framework to evaluate context based security policies. In this framework, context data is modeled and risk in security decisions is measured.
Step-by-step error/erasure decoding Reed-Solomon codes
Authors: Tung-Chou Chen, Che-Ho Wei, Shyue-Win Wei
Venue: Proceedings of the The 8th International Conference on Communication Systems - Volume 01 (2002)

A step-by-step error/erasure decoding algorithm for Reed-Solomon codes is presented. Compared with the standard algebraic decoding, this step-by-step error/erasure decoding algorithm does not need to find the coefficients of the error location polynomial, to search the error locators, and to calculate the error evaluator and error/erasure polynomials for obtaining the error and erasure values. This algorithm can detect whether each received code symbol is an error or erasure location or not and then directly find the corresponding error or erasure value in the manner of symbol-by-symbol.
Teaching real-time with a scheduler simulator
Authors: A. N. Kumar
Venue: Proceedings of the Frontiers in Education Conference, 2001. 31st Annual - Volume 02 (2001)

In this paper we describe a scheduler simulator for real-time tasks, RTsim, that can be used as a tool to teach real-time scheduling algorithms. It simulates a variety of preprogrammed scheduling policies for single and multiprocessor systems and simple algorithm variants introduced by its user. Using RTsim students can conduct experiments that will allow them to understand the effects of each policy given different load conditions and learn which policy is better for different workloads. We show how to use RTsim as a learning tool and the results achieved with its application on the real-time systems course taught at the B.Sc. on Computer Science at Paulista State University-Unesp-at Rio Preto.
Hyperbolic balance laws: Riemann invariants and the generalized Riemann problem
Authors: Matania Ben-Artzi, Jiequan Li
Venue: Numerische Mathematik (2007)

The Generalized Riemann Problem (GRP) for a nonlinear hyperbolic system of m balance laws (or alternatively &#x201c;quasi-conservative&#x201d; laws) in one space dimension is now well-known and can be formulated as follows: Given initial-data which are analytic on two sides of a discontinuity, determine the time evolution of the solution at the discontinuity. In particular, the GRP numerical scheme (second-order high resolution) is based on an analytical evaluation of the first time derivative. It turns out that this derivative depends only on the first-order spatial derivatives, hence the initial data can be taken as piecewise linear. The analytical solution is readily obtained for a single equation (m&#x00a0;=&#x00a0;1) and, more generally, if the system is endowed with a complete (coordinate) set of Riemann invariants. In this case it can be &#x201c;diagonalized&#x201d; and reduced to the scalar case. However, most systems with m&#x00a0;>&#x00a0;2 do not admit such a set of Riemann invariants. This paper introduces a generalization of this concept: weakly coupled systems (WCS). Such systems have only &#x201c;partial set&#x201d; of Riemann invariants, but these sets are weakly coupled in a way which enables a &#x201c;diagonalized&#x201d; treatment of the GRP. An important example of a WCS is the Euler system of compressible, nonisentropic fluid flow (m&#x00a0;=&#x00a0;3). The solution of the GRP discussed here is based on a careful analysis of rarefaction waves. A &#x201c;propagation of singularities&#x201d; argument is applied to appropriate Riemann invariants across the rarefaction fan. It serves to &#x201c;rotate&#x201d; initial spatial slopes into &#x201c;time derivative&#x201d;. In particular, the case of a &#x201c;sonic point&#x201d; is incorporated easily into the general treatment. A GRP scheme based on this solution is derived, and several numerical examples are presented. Special attention is given to the &#x201c;acoustic approximation&#x201d; of the analytical solution. It can be viewed as a proper linearization (different from the approach of Roe) of the nonlinear system. The resulting numerical scheme is the simplest (second-order, high-resolution) generalization of the Godunov scheme.
SSL splitting: securely serving data from untrusted caches
Authors: Chris Lesniewski-Laas, M. Frans Kaashoek
Venue: Proceedings of the 12th conference on USENIX Security Symposium - Volume 12 (2003)

A popular technique for reducing the bandwidth load on Web servers is to serve the content from proxies. Typically these hosts are trusted by the clients and server not to modify the data that they proxy. SSL splitting is a new technique for guaranteeing the integrity of data served from proxies without requiring changes to Web clients. Instead of relaying an insecure HTTP connection, an SSL splitting proxy simulates a normal Secure Sockets Layer (SSL) [7] connection with the client by merging authentication records from the server with data records from a cache. This technique reduces the bandwidth load on the server, while allowing an unmodified Web browser to verify that the data served from proxies is endorsed by the originating server. SSL splitting is implemented as a patch to the industry-standard OpenSSL library, with which the server is linked. In experiments replaying two-hour access. log traces taken from LCS Web sites over an ADSL link, SSL splitting reduces bandwidth consumption of the server by between 25% and 90% depending on the warmth of the cache and the redundancy of the trace. Uncached requests forwarded through the proxy exhibit latencies within approximately 5% of those of an unmodified SSL server.
A Multi-dimensional Reputation System Combined with Trust and Incentive Mechanisms in P2P File Sharing Systems
Authors: Mao Yang, Qinyuan Feng, Yafei Dai, Zheng Zhang
Venue: Proceedings of the 27th International Conference on Distributed Computing Systems Workshops (2007)

Free-riders and fake files are two important problems in P2P file sharing systems. Previous works have always used incentive mechanisms and trust mechanisms to ad- dress them respectively. In real systems however, a trust mechanism without incentive would face lack of users' enthusiasm and thus cause sparse relationship of direct trust while an incentive mechanism without trust could induce users' bad behavior. A novel reputation system is proposed in this paper that combines trust and incentive mechanisms. It uses files' vote and retention time, down- load volume and users' rank to construct a more extensive direct trust relationship and calculates a user's reputa- tion with a multi-trust algorithm. It can identify fake files and provide service differentiation with reputation. Im- plementation and some security consideration in DHT are also discussed.
Application of MOKA methodology in generative model creation using CATIA
Authors: Wojciech Skarka
Venue: Engineering Applications of Artificial Intelligence (2007)

The paper presents the method of generative model creation in CATIA system. The method covers not only the very process of model creation in CATIA system but also the whole complexity of the process, beginning with knowledge identification and acquisition and finally with explanation system creation that facilitates and justifies the usage of generative model itself. The method, in one of its parts, uses MOKA methodology and in particular its informal knowledge model and knowledge representation for generative model, which is special for CATIA.
2007 Special Issue: Online design of an echo state network based wide area monitor for a multimachine power system
Authors: Ganesh K. Venayagamoorthy
Venue: Neural Networks (2007)

With deregulation and growth of the power industry, many power system elements such as generators, transmission lines, are driven to operate near their maximum capacity, especially those serving heavy load centres. Wide Area Controllers (WACs) using wide area or global signals can provide remote auxiliary control signals to local controllers such as automatic voltage regulators, power system stabilizers, etc. to damp out system oscillations. However, since the power system is highly nonlinear with fast changing dynamics, it is a challenging problem to design an online system monitor/estimator, which can provide dynamic intra-area and inter-area information such speed deviations of generators to an adaptive WAC continuously. This paper presents a new kind of recurrent neural networks, called the Echo State Network (ESN), for the online design of a Wide Area Monitor (WAM) for a multimachine power system. A single ESN is used to predict the speed deviations of four generators in two different areas. The performance of this ESN WAM is evaluated for small and large disturbances on the power system. Results for an ESN based WAM and a Time-Delayed Neural Network (TDNN)-based WAM are presented and compared. The advantages of the ESN WAM are that it learns the dynamics of the power system in a shorter training time with a higher accuracy and with considerably fewer weights to be adapted compared to the design-based on a TDNN.
Delay-Balanced Smart Repeaters for On-Chip Global Signaling
Authors: Roshan Weerasekera, Dinesh Pamunuwa, Li-Rong Zheng, Hannu Tenhunen
Venue: Proceedings of the 20th International Conference on VLSI Design held jointly with 6th International Conference: Embedded Systems (2007)

In this paper we propose a smart driver, whose drive strength is dynamically altered depending on the relative bit pattern, by partitioning it into a Main Driver and Assistant Driver. For a higher effective load capacitance both drivers switch, while for a lower effective capacitance the assistant driver is quiet. It is shown that in an UMC 0.18ìm technology the potential peak power saving, for typical global wire lengths, can be as much 18% with a 12% jitter reduction over a traditional repeater for a data rate of 1Gb/s.
A Multi-Resolution Compression Scheme for EfficientWindow Queries over Road Network Databases
Authors: Ali Khoshgozaran, Ali Khodaei, Mehdi Sharifzadeh, Cyrus Shahabi
Venue: Proceedings of the Sixth IEEE International Conference on Data Mining - Workshops (2006)

Vector data and in particular road networks are being queried, hosted, and processed by many application domains such as mobile computing. However, many hosting/ processing clients such as PDAs cannot afford this bulky data due to their storage and transmission limitations. In particular, the result of a typical spatial query such as window query is too huge for a transfer-and-store scenario. While several general vector data compression schemes have been studied by different communities, we propose a novel approach in vector data compression which is easily integrated within a geospatial query processing system. It uses line aggregation to reduce the number of relevant tuples and Huffman compression to achieve a multi-resolution compressed representation of a road network database. Our empirical results verify that our approach exhibits both a high compression ratio and fast query processing.
Using a large vocabulary continuous speech recognizer for a constrained domain with limited training
Authors: M. Siu
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1999. on 1999 IEEE International Conference - Volume 01 (1999)

How to train a speech recognizer with limited amount of training data is of interest to many researcher. We describe how we use BBN's Byblos large vocabulary continuous speech recognition (LVCSR) system for the military air-traffic-control domain where we have less than an hour of training data. We investigate three ways to deal with the limited training data: (1) re-configure the LVCSR system to use fewer parameters, (2) incorporate out-of-domain data, and, (3) use pragmatic information, such as speaker identity and controller function to improve recognition performance. We compare the LVCSR performance to that of the tied-mixture recognizer that is designed for a limited vocabulary. We show that the reconfigured LVCSR system outperforms the tied-mixture system by 10% in absolute word error rate. When enough data is available per speaker, vocal tract length normalization and supervised adaptation techniques can further improve performance by 6% even for this domain with limited training. We also show that the use of out-of-domain data and pragmatic information, if available, can each further improve performance by 1-3%.
Using end-user latency to manage internet infrastructure
Authors: J. Bradley Chen, Michael Perkowitz
Venue: Proceedings of the 2nd conference on Industrial Experiences with Systems Software - Volume 2 (2002)

Performance is a requirement for all interactive applications. For Internet-based distributed applications, the need is even more acute - users have a choice about where they browse, and if a site's performance frustrates them they may never return. The goal of this paper is to demonstrate the power of end-to-end latency measurements of actual site traffic for assuring the performance of Internet applications. We briefly describe a system for collecting true end-to-end latency measurements from real site traffic and describe how such measurements can be used to improve user experience. We give examples to show how to use such measurements to evaluate site performance, pinpoint failures, and elucidate capacity issues. We argue that, as services delivered via the Internet become both more widespread and more complex, accurate measurement of site performance is of vital importance for both maintaining and improving end-user experience.
Comprehending Aspect-Oriented Programs: Challenges and Open Issues
Authors: Giuseppe A. Di Lucca, Michael Smit, Bruce Fraser, Eleni Stroulia, H. James Hoover
Venue: Proceedings of the 15th IEEE International Conference on Program Comprehension (2007)

Aspect Oriented Programming (AOP) supports the encapsulation of concerns cutting across the logical design of object-oriented software, by introducing aspects as a new unit of code. Code fragments, defined within aspects, such as advice or inter-type declarations, can be composed together with traditional system units, such as classes in OO code, using quantification expressions that specify where such fragments are to be injected and executed. The introduction of aspect-orientation in object-oriented software development raises two interesting comprehension questions. First, is the comprehension of AO software more difficult than traditional objectoriented software? Second, can aspects support comprehension tasks of object-oriented developers?
Automatic Identification of Shot Body Region from Clinical Photographies
Authors: Hitoshi Iyatomi, Hiroshi Oka, Masaru Tanaka, Koichi Ogawa
Venue: Proceedings of the 35th Applied Imagery and Pattern Recognition Workshop (2006)

Administration of clinical photographs taken by commonly used digital camera often requires troublesome manual operation. In this paper, we made a prototype scheme of automatic photographed area identification from clinical images to help or reduce administration task. A total of 8047 clinical photographs taken in department of dermatology, Keio University Hospital, were classified into 11 categories; head, hair, upper limb, lower limb, trunk, palm, sole, back of hand, back of foot, finger & detent and genital; to meet request by several dermatologists and we developed separate linear classifiers for each body region. The developed classifiers achieved an 82.8% in sensitivity (SE) and an 82.0% of specificity (SP) in average. In addition, integration of these classifiers with consideration of the feature space of each body region improved SP of 2.3% and precision (PR) of 3.0% at a maximum when the classification threshold was set to around 75% in SE. The proposed scheme requires only photographs to identify the photographed area and therefore it can be easily applied for DICOM (digital image and communication in medicine) system that is commonly used in clinical practice or other medical database systems.
Adaptive paraunitary filter banks for principal and minor subspace analysis
Authors: S. C. Douglas
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1999. on 1999 IEEE International Conference - Volume 02 (1999)

Paraunitary filter banks are important for several signal processing tasks. We consider the task of adapting the coefficients of a multichannel FIR paraunitary filter bank via gradient ascent or descent on a chosen cost function. The proposed generalized algorithms inherently adapt the system's parameters in the space of paraunitary filters. Modifications and simplifications of the techniques for spatio-temporal principal and minor subspace analysis are described. Simulations verify one algorithm's useful behavior in this task.
Assuring Quality and Usability in Open Source Software Development
Authors: Henrik Hedberg, Netta Iivari, Mikko Rajanen, Lasse Harjumaa
Venue: Proceedings of the 29th International Conference on Software Engineering Workshops (2007)

This paper reviews literature on quality and usability assurance in open source software (OSS) development, focusing specifically on OSS that is targeted at a large user population, which does not consist only of OSS developers anymore. In this type of OSS development, the "naïve', non computer professional users should be taken into account and usability of OSS improved. Furthermore, software quality becomes a very relevant issue to be assured. We contrast OSS literature on quality and usability with prescriptive literatures derived from the fields of software engineering and human computer interaction. We present a summary of the current practices utilized to assure quality and usability in OSS development, and recommend practices to be used in this context. We also point out limitations in the existing research and suggest paths for future work.
A calibration and validation process (cavp) for complex adaptive system simulation
Authors: Donald E. Brown
Venue:  (2006)

The Calibration and Validation Process (CAVP) for Complex Adaptive System Simulation (CASS) iteratively calibrates constrained simulation agent parameter input sets to produce acceptable simulation measure of performance outputs as compared to target mean values. If all measures of performance are calibrated by a single input agent set, the CAVP validates complex adaptive system simulation. Using response surface methods and data mining techniques to guide each iteration to a better result, the CAVP will find an agent parameter input point (in multiple dimensions) that will validate a CASS if such a point exists. The CAVP provides an efficient method to calibrate CASS agent input parameters. It is an information-engineering based process that composite maps agent-based simulation outputs to agent parameter inputs (control variables) within a complex adaptive system simulation environment (exogenous variables). This process enables the simulation modeler to calibrate a set of agents against a standard of system output that has been derived either empirically or through expert opinion. Data is generated according to an efficient Nearly Orthogonal Latin Hypercube (NOLH) experimental design to reduce computation expense and efficiently search the constrained search space. The agent parameter inputs are constrained according to reasonable ranges, and the outputs are mapped buck to inputs through data mining techniques such as classification and regression trees, regression, and multiple response surface optimization. Further, the CAVP provides a means to adjudicate the validity of an agent-based simulation by comparing multiple response surfaces of measures of performance. The CAVP extends the capabilities of the Extended Response Surface Method by strengthening Step 5: Calibrate the simulation. The CAVP also presents a novel approach to agent-based simulation validation by determining the fitness of overall simulation output, and then using advanced data mining techniques to determine the influence of heterogeneous agent input parameters.