ppxscal/embedding_network huggingface dataset:
Lifelong learning and the virtual campus-a proposal for asynchronous learning
Authors: R. Ibieta
Venue: Proceedings of the 28th Annual Frontiers in Education - Volume 03 (1998)

Lifelong learning has traditionally been a challenge for highly specialized professions such as engineering, where the central core of knowledge tends to change continuously. Emerging technologies such as the Internet multimedia-based training, computer-based videoconferencing and others will facilitate the access to critical, data rich information by professionals all over the world increasing demand for this kind of learning will pose new challenges for learning institutions that are not prepared to serve this potential audience. This paper describes the state-of-the-art in distance learning technologies and the implications for both students and learning institutions interested in creating the "virtual campuses" of the future. 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
Utilizing rapid prototyping to enhance undergraduate engineering education
Authors: R. E. Stamper
Venue: Proceedings of the 30th Annual Frontiers in Education - Volume 02 (2000)

Rapid prototyping is a term used to describe a group of fabrication processes that are used to quickly create physical prototypes from CAD solid model data. University operated rapid prototyping equipment is often being used as part of research efforts or for the purpose of training students how to use rapid prototyping equipment. However, rapid prototyping technologies are also starting to be used to enhance the undergraduate engineering education experience by supporting other educational objectives. This paper discusses how a rapid prototyping machine was used in two different undergraduate mechanical engineering classes to add excitement and realism. The two classes are a design methodologies class for third year students and the senior mechanical engineering laboratory.
Remark on Algorithm 644
Authors: Masao Kodama
Venue: ACM Transactions on Mathematical Software (TOMS) (2007)

This remark details correction for errors in the functions which compute the modified Bessel function of the second kind and the log of the gamma function. In both cases these errors cause a loss of precision for a small range of values of the &nu; argument. These routines are used in the calculation of a number of other functions within the package whose accuracy is thus similarly affected.
Checking safety properties on-the-fly with the sweep-line method
Authors: Guy Edward Gallasch, Jonathan Billington, Somsak Vanit-Anunchai, Lars Michael Kristensen
Venue: International Journal on Software Tools for Technology Transfer (STTT) (2007)

The sweep-line state space method allows states to be deleted from memory during state exploration, thus alleviating the state explosion problem. Properties of the system (such as the absence of deadlocks) can then be verified on-the-fly. This paper presents an extension to the sweep-line method that allows on-the-fly checking of safety properties expressed as sequences of actions of the modelled system. This has been implemented in a prototype sweep-line library for Coloured Petri nets. We evaluate the prototype by applying it to the connection management procedures of the Datagram Congestion Control Protocol, a new Internet transport protocol.
Practical Camera Auto Calibration using Semidefinite Programming
Authors: Motilal Agrawal
Venue: Proceedings of the IEEE Workshop on Motion and Video Computing (2007)

We describe a novel approach to the camera auto calibration problem. The uncalibrated camera is first moved in a static scene and feature points are matched across frames to obtain the feature tracks. Mismatches in these tracks are identified by computing the fundamental matrices between adjacent frames. The inlier feature tracks are then used to obtain a projective structure and motion of the camera using iterative perspective factorization scheme. The novelty of our approach lies in the application of semidefinite programming for recovering the camera focal lengths and the principal point. Semidefinite programming was used in our earlier work [1] to recover focal lengths under the assumption of known principal points. In this paper, we relax the constraint of known principal point and do an exhaustive search for the principal points. Moreover, we describe an end-to-end system for auto calibration and present experimental results to evaluate our approach.
Closed-form phase retrieval of images from the zeros of 1-D signals obtained using the Good-Thomas FFT
Authors: S. Petroudi
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 04 (2000)

The 2-D discrete phase retrieval problem is to reconstruct an image defined at integer coordinates and having known finite spatial extent from the magnitude of its discrete Fourier transform. Most methods for solving this problem are iterative but not POCS, and they tend to stagnate. We have shown that a subband decomposition can be used to divide a large phase retrieval problem into smaller problems defined over subbands. However, these numerous smaller phase retrieval problems must be solved efficiently. This paper uses the Good-Thomas FFT to map the 2-D problem into a 1-D problem of reconstructing the signal formed by concatenating rows of the image with zero bands. The z-transform zeros of this 1-D signal are close enough to the unit circle to be found from local minima of the (known) DFT magnitude. The 1-D signal can then be reconstructed in closed form.
Role of prefiltering in unsupervised video segmentation
Authors: H. M. Karaca
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 04 (2000)

In this study, we address the problem of prefiltering before segmentation. Prefiltering is quite important since it simplifies the data, producing flat zones without computing the contour information (Salembier and Pardas, 1994). Morphological filters with reconstruction restore the contour of the components. However, covered and uncovered areas in moving objects may be connected during the reconstruction process. In this case, open-close by partial reconstruction filters remove those artifacts in the background. After that, the contours of the regions can be located by the watershed algorithm. Although the number of resulting regions at the end of watershed with open-close by partial reconstruction is more than local averaging, applying a premerging by comparing the difference of mean gray values to these regions results in less number and greater-sized regions. Therefore, open-close filtering makes merging of more regions possible.
Pseudo Real-Time System for Visualisation of 3D Scenes
Authors: Bo Tang, Djamel Ait-Boudaoud, Lik-Kwan Shark, Bogdan J. Matuszewski
Venue: Proceedings of the Geometric Modelling and Imaging (2007)

A novel pseudo real-time 3D visualisation system is proposed in this paper. The proposed system has been developed using the TI (Texas Instruments) DM642 EVM board which is a standalone Digital Media Processing board. The system also includes a stereo video capture module consisting of two PAL cameras and a 3D display unit for visualisation of 3D video input. The core algorithm utilises images captured from the cameras and generates 6 virtual in between views using interpolation techniques. The combined views (eight views of 2D images) are displayed on the 3D monitor using a proprietary method developed specifically for X3D monitors. The advantage of the proposed system is that real 3D impressions are able to be visualised in front of the 3D monitor in pseudo real-time without any special glasses. The proposed system has been evaluated on a number of real scenes. The limitations of our system will be discussed and the corresponding solutions will be given at the end of this paper.
Automatic Test Generation applied to a Vocal Service
Authors: Elisangela Rodrigues Vieira, Ana Cavalli
Venue: Proceedings of the Second International Conference on Systems (2007)

Telecommunication applications have been introduced in the domain of timed systems. It has required new models, methods and tools, able to lead with timed constraints in all phases of the system development. This paper concerns an automatic test generation applied to an industrial application furnished by France Telecom, where time constraints are taken into account. In our approach, systems are modeled with IF (Intermediate Format). IF is an intermediate model used to specify and validate asynchronous formal systems, based on communication timed automata. In order to optimize the test sequences generation, we use an algorithm called Hit-or-Jump. This algorithm has been efficiently used in test generations of protocols, services and timed systems, but until now it has been restricted to SDL specifications. This combined approach allows the use of known languages in the system specification (IF accepts specifications written in SDL or UML), and an efficient method to test generation based on test purposes.
Modeling complex contacts involving deformable objects for haptic interaction
Authors: Jing Xiao
Venue:  (2006)

Haptic interaction allows a human user to touch and feel objects in virtual or remote environments with the tactile feedback as if he/she is handling real objects. This is achieved by simulating the force/torque of the physical interaction and displaying the simulated force/torque via a force reflecting device. Haptic rendering involving deformable objects can be useful in many applications, from surgical simulation and training, to virtual prototyping, to tele-operation, etc. However, existing work is restricted to simplified task scenarios of limited scopes. The work of this dissertation aims to broaden the scope of deformable object modeling and advance the state of the art in haptic rendering involving deformable objects. Three approaches are introduced to modeling different types of contacts and interactions involving deformable objects in three different scenarios, which are inspired particularly by potential applications in surgical simulations and virtual assembly tasks. Contact forces/torques and shape deformation are modeled. These approaches have been implemented and tested in many examples. In all cases, real-time and physically realistic haptic interactions were achieved.
Mobile TV - To Live or Die by Content
Authors: Christer Carlsson, Pirkko Walden
Venue: Proceedings of the 40th Annual Hawaii International Conference on System Sciences (2007)

Mobile TV is described as a natural and evolutionary next step as mobile phones get more multimedia features. Mobile network operators expect mobile TV to support the adoption of 3G as they expect consumers to start shifting the use of mobile phones from simply communicating with each others to proactively searching for information. Here the logic is not very clear as TV basically is a broadcast medium for passive reception of content which is pre-selected, produced and transmitted and thus seems to be in contradiction with the aim at a proactive search for information. Then there is another question: do people want mobile TV and if so, when, where and what would they want to watch? We have conducted an empirical study among the participants in a pilot experiment with mobile TV in Finland in order to find out some reasons for a possible adoption and use of mobile TV.
An instantiable speech biometrics module with natural language interface: implementation in the telephony environment
Authors: J. Navratil
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 02 (2000)

This paper describes an implementation of the concept of conversational speech biometrics approach to personal authentication in the telephony environment. An application-independent module including a natural language-enabled part for verbal verification and identification and an acoustic speaker recognition engine for voice-print analysis are combined using a special verification/identification protocol which allows the application to adapt the session according to the dialog development and the query/command security. The results validate the feasibility and advantages of the concept of integrating the speaker and speech recognition technology. Users familiar with the system can log into the system with 2.7% or 3.2% false rejection and ca. 3/spl times/10/sup -11/% or 10/sup -6/% false acceptance rates in about 40 sec or 20 sec respectively. This makes speaker recognition for the first time deployable for high security applications even with today's technology-a claim that can't be made with other speaker recognition technology. The system has a client-server architecture and is suitable for various applications and platforms.
Probing TCP implementations
Authors: Douglas E. Comer, John C. Lin
Venue: Proceedings of the USENIX Summer 1994 Technical Conference on USENIX Summer 1994 Technical Conference - Volume 1 (1994)

In this paper, we demonstrate a technique called active probing used to study TCP implementations. Active probing treats a TCP implementation as a black box, and uses a set of procedures to probe the black box. By studying the way TCP responds to the probes, one can deduce several characteristics of the implementation. The technique is particularly useful if TCP source code is unavailable. To demonstrate the technique, the paper shows example probe procedures that examine three aspects of TCP. The results are informative: they reveal implementation flaws, protocol violations, and the details of design decisions in five vendor-supported TCP implementations. The results of our experiment suggest that active probing can be used to test TCP implementations.
Stability of the max-weight routing and scheduling protocol in dynamic networks and at critical loads
Authors: Matthew Andrews, Kyomin Jung, Alexander Stolyar
Venue: Proceedings of the thirty-ninth annual ACM symposium on Theory of computing (2007)

We study the stability of the max-weight protocol for combined routingand scheduling in communication networks. Previous work has shownthat this protocol is stable for adversarial multicommodity trafficin subcritically loaded static networks and for single-commoditytraffic in critically loaded dynamic networks. We show: The max-weight protocol is stable for adversarial multicommodity traffic in adversarial dynamic networks whenever the network is subcriticallyloaded. The max-weight protocol is stable for fixed multicommodity trafficin fixed networks even if the network is critically loaded. The latter result has implications for the running time of themax-weight protocol when it is used to solve multicommodity flowproblems. In particular, for a fixed problem instance we show thatif the value of the optimum solution is known, the max-weight protocolfinds a flow that is within a (1-ε)-factor of optimal in time O(1/ε) (improving the previous bound of O(1/ε2)). If thevalue of the optimum solution is not known, we show how to apply themax-weight algorithm in a binary search procedure that runs in O(1/ε) time.
The Efficiency of Periodic Rekeying in Dynamic Group Key Management
Authors: Tam Pham, Paul A. Watters
Venue: Proceedings of the Fourth European Conference on Universal Multiservice Networks (2007)

The efficiency of group key management is a key issue in secure group communications, since the group key must be renewed each time the group membership changes. This paper examines the performance of a periodic rekeying technique for the key management of groups that exhibit bursty behaviour. Experimental results demonstrate that this technique costs far fewer key generations than existing approaches, and is therefore more efficient in terms of computation. When the pre-processing of joining members can be performed during the rekeying period, this technique reduces the rekeying time at the end of the rekeying period to the lower bound.
High quality MELP coding at bit-rates around 4 kb/s
Authors: J. Stachurski
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1999. on 1999 IEEE International Conference - Volume 01 (1999)

A number of coding techniques have been reported to achieve near toll quality synthesized speech at bit-rates around 4 kb/s. These include variants of code excited linear prediction (CELP), sinusoidal transform coding (STC) and multi-band excitation (MBE). While CELP has been an effective technique for bit-rates above 6 kb/s, STC, MBE, waveform interpolation (WI) and mixed excitation linear prediction (MELP) models seem to be attractive at bit-rates below 3 kb/s. We present a system to encode speech with high quality using MELP, a technique previously demonstrated to be effective at bit-rates of 1.6-2.4 kb/s. We have enhanced the MELP model producing significantly higher speech quality at bit-rates above 2.4 kb/s. We describe the development and testing of a high quality 4 kb/s MELP coder.
Automatic generation of SCTP test cases in multiservice switching system
Authors: Hyun-jeong Lee, Nam-kyung Uhm, Young-il Choi, Byung-sun Lee, Kyung-pyo Jun
Venue: Integrated Computer-Aided Engineering (2002)

SCTP is a transport protocol that transfers SS7 signaling from PSTN to packet network using IP protocol, and can be used in many areas like TCP and UDP. CPN, the extended model of Petri Nets, is a graphical oriented language for design, specification, simulation and verification of systems. Design/CPN is a tool package that supports the use of CPN. In this paper, we propose a method to generate SCTP test cases automatically using Design/CPN. First, we explain how to transform an SCTP association state diagram into a CPN form, and then we explain how to generate test cases from an OG and descriptors resulting from Design/CPN. Using our method, we can generate test cases more conveniently without errors and get more improved test coverage than existing manual methods such as T-method, U-method, D-method and W-method. It could be used as the basis of the automatic test environment for telecommunication protocols.
Game Relations and Metrics
Authors: Luca de Alfaro, Rupak Majumdar, Vishwanath Raman, Marielle Stoelinga
Venue: Proceedings of the 22nd Annual IEEE Symposium on Logic in Computer Science (2007)

We consider two-player games played over finite state spaces for an infinite number of rounds. At each state, the players simultaneously choose moves; the moves determine a successor state. It is often advantageous for players to choose probability distributions over moves, rather than single moves. Given a goal (e.g., "reach a target state"), the question of winning is thus a probabilistic one: "what is the maximal probability of winning from a given state?". On these game structures, two fundamental notions are those of equivalences and metrics. Given a set of winning conditions, two states are equivalent if the players can win the same games with the same probability from both states. Metrics provide a bound on the difference in the probabilities of winning across states, capturing a quantitative notion of state "similarity". We introduce equivalences and metrics for two-player game structures, and we show that they characterize the difference in probability of winning games whose goals are expressed in the quantitative ì-calculus. The quantitative ì- calculus can express a large set of goals, including reachability, safety, and ù-regular properties. Thus, we claim that our relations and metrics provide the canonical extensions to games, of the classical notion of bisimulation for transition systems. We develop our results both for equivalences and metrics, which generalize bisimulation, and for asymmetrical versions, which generalize simulation.
Realizing Live Sequence Charts in SystemVerilog
Authors: Hai H. Wang, Shengchao Qin, Jun Sun, Jin Song Dong
Venue: Proceedings of the First Joint IEEE/IFIP Symposium on Theoretical Aspects of Software Engineering (2007)

The design of an embedded control system starts with an investigation of properties and behaviors of the process evolving within its environment, and an analysis of the requirement for its safety performance. In early stages, system requirements are often specified as scenarios of behavior using sequence charts for different use cases. This specification must be precise, intuitive and expressive enough to capture different aspects of embedded control systems. As a rather rich and useful extension to the classical message sequence charts, Live Sequence Charts (LSC), which provide a rich collection of constructs for specifying both possible and mandatory behaviors, are very suitable for designing an embedded control system. However, it is not a trivial task to realize a high-level design model in executable program codes effectively and correctly. This paper tackles the challenging task by providing a mapping algorithm to automatically synthesize SystemVerilog programs from given LSC specifications.
Distributed quota enforcement for spam control
Authors: Michael Walfish, J. D. Zamfirescu, Hari Balakrishnan, David Karger, Scott Shenker
Venue: Proceedings of the 3rd conference on Networked Systems Design & Implementation - Volume 3 (2006)

Spam, by overwhelming inboxes, has made email a less reliable medium than it was just a few years ago. Spam filters are undeniably useful but unfortunately can flag nonspam as spam. To restore email's reliability, a recent spam control approach grants quotas of stamps to senders and has the receiver communicate with a well-known quota enforcer to verify that the stamp on the email is fresh and to cancel the stamp to prevent reuse. The literature has several proposals based on this general idea but no complete system design and implementation that: scales to today's email load (which requires the enforcer to be distributed over many hosts and to tolerate faults in them), imposes minimal trust assumptions, resists attack, and upholds today's email privacy. This paper describes the design, implementation, analysis, and experimental evaluation of DQE, a spam control system that meets these challenges. DQE's enforcer occupies a point in the design spectrum notable for simplicity: mutually untrusting nodes implement a storage abstraction but avoid neighbor maintenance, replica maintenance, and heavyweight cryptography.
Blind closed-form array response estimation in wireless communication
Authors: Liang Jin
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1999. on 1999 IEEE International Conference - Volume 05 (1999)

A closed-form array response estimation (CARE) technique for blind source separation in wireless communication is developed. By exploiting the data structure of second-order statistics of the array output in the presence of multipath, we construct a signature matrix in such a way that its eigenvectors corresponding to non-zero eigenvalues are just the array response vectors. Thus a closed-form solution of array response can be obtained by eigen-decomposition. The theoretical analysis and the simulations show that the proposed method achieves array response estimation with little constraint on signal property and propagation environment such as scatters or angular spread. Moreover, the array considered here can be of arbitrary geometry and even uncalibrated.