ppxscal/embedding_network huggingface dataset:
Using a Floating Origin to Improve Fidelity and Performance of Large, Distributed Virtual Worlds
Authors: Chris Thorne
Venue: Proceedings of the 2005 International Conference on Cyberworlds (2005)

Large Virtual Worlds (VWs) are increasingly common in the computer graphics areas of simulation, games, geospatial or scientific visualisation. In such VWs, simulated motion of the viewpoint and other objects becomes jittery and lacking in realism when far from the world's origin. Shape and appearance of objects can also degenerate. Since these effects depend on position in space, they will be collectively termed Spatial Jitter (SJ). Traditional solutions to SJ embody the idea that viewpoint motion through the VW must involve a change of the viewpoint's coordinates. This notion of viewpoint motion increases design complexity and the processing overhead of code written to counter SJ. A Floating Origin (FO) approach is presented which floats the world's origin with the viewpoint when navigating a coninuous VW, eliminating SJ effects and lowering design and processing overhead. It ensures constant high fidelity in contrast to the continuously varying fidelity of conventional solutions.
GAP: a GPSS/FORTRAN package
Authors: Robert J. Wimmert
Venue: ACM SIGSIM Simulation Digest (1980)

The GAP package has been developed to permit the linking of standard GPSS models to a series of FORTRAN subprograms. Since the GAP subprograms are transparent to the user, knowledge of the FORTRAN language is not needed. GAP provides an easy mechanism to obtain, among other things, values from a number of standard statistical distributions, permits the loading of MSAVEVALUEs and other SNAs using data cards and provides statistical analysis of the GPSS model output. 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
Dealing with Emergent Properties in Embedded Systems
Authors: Iain Bate
Venue: Proceedings of the 11th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications (2005)

The development of many systems suffer from unexpected problems during development leading to time and cost penalties. A common situation that leads to problems is when components are integrated and un-anticipated features are formed. These features are often termed emergent properties. In this paper, a compositional approach is adopted where components are parameterised with extra information that can then be used to understand the implications of integration and mapping.
Fingerprint Verification Based on Fixed Length Square Finger Code
Authors: Pradeep M. Patil, Shekhar R. Suralkar, Hemant K. Abhyankar
Venue: Proceedings of the 17th IEEE International Conference on Tools with Artificial Intelligence (2005)

In this paper a novel method is presented for generation of a fixed length square finger code of size 16 × 16 × 4. It uses a set of Gabor filters for extracting fingerprint features from gray scale image cropped in the size of 128 × 128 pixels using its core point as the center. Experimental results show that the recognition rate based on the Euclidean distance between the two corresponding Gabor filter finger codes with verification accuracy of 93%. Since, the fingerprint matching is based on the Euclidean distance between two corresponding finger codes, it is extremely fast. This reveals that by setting the parameters to appropriate values, the finger code generated is more efficient and suitable than conventional methods for a small-scale fingerprint recognition system.
Dial-Up Internet Access: A Two-Provider Cost Model
Authors: Andrew M. Ross, J. George Shanthikumar
Venue: Queueing Systems: Theory and Applications (2005)

We present a cost model for splitting Internet dial-up traffic (which varies by time-of-day) between two large modem banks. One of the modem banks charges by the hour, the other charges for the peak number-in-system during the day. To study if the possible savings are enough to make the effort worthwhile, we formulate a clairvoyant ("perfect information") Integer Program that is equivalent to a network flow problem. This leads us to use a ceiling policy. In the stochastic control case, we use a Modified Offered Load (MOL) approximation to explore the properties of the system, and develop a square-root-type rule to set the ceiling in the homogeneous case. We also use simulation to determine an optimal ceiling when we cannot route individual calls precisely. We propose approximations that may be computed for any call duration distribution, and compare their answers to exact differential-equation procedures for Exponential call durations.
Parameter Optimization Problems for Multilayer Optical Coatings
Authors: P. I. Stetsyuk, A. B. Mitsa
Venue: Cybernetics and Systems Analysis (2005)

Two problems of finding optimal parameters for multilayer optical coatings are considered. They are formulated as multiextremal nonlinear programming problems with a complex objective function. Finding local extrema by first-order methods is discussed. The ways of calculating the gradient of the objective function depending on the number of layers in the optical coating are analyzed.
The Role of a Second Reservoir in an Open BCS Model
Authors: F. Bagarello
Venue: Open Systems Information Dynamics (2005)

In this paper we use the stochastic limit approach (SLA) in order to analyze some generalized versions of the open BCS model first introduced by Buffet and Martin and recently analyzed by the author using the SLA. In particular, considering different models, we discuss the role of a second reservoir interacting with the first one (but not with the system) in the computation of the critical temperature corresponding to the transition from a normal to a superconducting phase.
Peer-to-peer resource discovery in mobile Grids
Authors: Luciana dos S. Lima, Antônio T. A. Gomes, Artur Ziviani, Markus Endler, Luiz F. G. Soares, Bruno Schulze
Venue: Proceedings of the 3rd international workshop on Middleware for grid computing (2005)

Grids are likely to be the mainstay of distributed computing. Grid was firstly applied as a concept for sharing computing resources among wired nodes, but there has been a growing interest in extending this concept to mobile environments. Although significant work has been done towards mobile grids, much of it has followed centralized approaches based on infrastructure wireless networks. We believe that a less restrictive, decentralized approach that supports mobile collaboration in ad-hoc wireless networks can cater for novel grid applications. To address this issue, we propose a middleware architecture called MoGrid. MoGrid orchestrates the distribution of grid tasks among mobile devices in a peer-to-peer (P2P) fashion. In this paper, we focus on the P2P Discovery Protocol (P2PDP), which is a central element of our architecture. P2PDP aids in distributing tasks among the most resourceful devices, while mitigating the overhead of control messages exchanged among them. We describe a prototype implementation of our architecture and discuss some issues related to the adoption of P2PDP as an ad-hoc resource discovery mechanism in mobile grids.
A Simulation Study of TCP over the IEEE 802.15.3 MAC
Authors: Kwan-Wu Chin, Darryn Lowe
Venue: Proceedings of the The IEEE Conference on Local Computer Networks 30th Anniversary (2005)

This paper presents the impact of IEEE 802.15.3 MAC's channel time allocation methods on a TCP flow's performance. We show the importance of having super rate and appropriately sized channel time allocations (CTAs).
An analysis of computer anxiety among school teachers in a rural mississippi county
Authors: Argentini Anderson
Venue:  (2005)

This study addressed the lack of investigation of the presence of computer anxiety in rural school teachers. The primary purpose of this study was threefold: (1) to determine if computer anxiety exists in public elementary, middle, and secondary school teachers in a rural county in Mississippi, (2) to ascertain if there was a statistically significant relationship between computer anxiety of the teachers and the following demographic variables: age, gender, race, and educational level, and (3) to determine the ways these teachers use computers and computer applications in the classroom. A census design was used to gather the data from the Noxubee County School District. In order to gather the data, a 52 item questionnaire was developed&mdash;12 of the questions were standard demographical and computer use questions and the remaining 40 questions were a modified version of Oetting's (1983) Long Form Computer Anxiety Scale (COMPAS) Instrument. To analyze the data, two techniques were utilized&mdash;descriptive statistics and an Analysis of Variance. These techniques revealed that the majority of the rural school teachers surveyed used computers and applications for word processing and for research. The study also found that age, race, gender, and the level of educational attainment were not statistically significant predictors of computer anxiety in these teachers. From these results, it was concluded that appropriate training programs should be developed to help these teachers cope with computer anxiety. It was also concluded that these teachers should be trained in the ways that technology can be used in their work environment.
Delay and Throughput Analysis of IEEE 802.11e EDCA with Starvation Prediction
Authors: Paal E. Engelstad, Olav N. Osterbo
Venue: Proceedings of the The IEEE Conference on Local Computer Networks 30th Anniversary (2005)

An analytical model is proposed to describe the priority schemes of the Enhanced Distributed Channel Access (EDCA) mechanism of the IEEE 802.11e standard. EDCA provides class-based differentiated Quality of Service (QoS) to IEEE 802.11 WLANs. The main contribution of this paper opposed to other works is that the model predicts the full delay distribution through its z-transform. Furthermore, the mean delay, throughput and frame dropping probabilities of the different traffic classes are found in the whole range from a lightly loaded, non-saturated channel to a heavily congested, saturated medium. Moreover, the model describes differentiation based on different Arbitration Inter-Frame Space (AIFS) values, in addition to the other adjustable parameters (i.e. window-sizes, retransmission limits, transmission opportunity (TXOP) lengths etc.) also encompassed by previous models. AIFS differentiation is described by a simple equation that enables access points to predict at which traffic loads starvation of a traffic class will occur. The model is calculated numerically and validated against simulation results. We observed a good match between the analytical model and simulations.
On the security of group communication schemes based on symmetric key cryptosystems
Authors: Shouhuai Xu
Venue: Proceedings of the 3rd ACM workshop on Security of ad hoc and sensor networks (2005)

Many emerging applications in both wired and wireless networks, such as information dissemination and distributed collaboration in an adversarial environment, need support of secure group communications. There have been many such schemes in the setting of wired networks. These schemes can be directly adopted in, or appropriately adapted to, the setting of wireless networks such as mobile ad hoc networks (MANETs) and sensor networks. In this paper we show that the popular group communication schemes that we have examined are vulnerable to the following attack: an outsider adversary who compromises a legitimate group member could obtain some or all past group keys as well as the current group key; this is in sharp contrast to the widely-accepted belief that a such adversary can only obtain the current group key. This attack is very powerful also because it provides the adversary the following flexibility: since the adversary knows which members are the "most valuable" ones from its own perspective of view, compromise of any such member leads to the exposure of all the past and current group keys. This flexibility is particularly relevant in the setting of MANETs and sensor networks because they are typically deployed in a small area and the adversary can capture and compromise the easiest-to-obtain node. In order to deal with this powerful attack, we formalize two security models for stateful and stateless group communication schemes, respectively. We show that some practical methods can make a subclass of the group communication schemes immune to this attack at the following extra expense: at each rekeying event, a group member conducts logarithmically-many pseudorandom function evaluations.
Toward best maintenance practices in communications network management
Authors: Faouzi Kamoun
Venue: International Journal of Network Management (2005)

Best maintenance practices in communications networks management are benchmarking standards that, if carefully implemented, will enhance the integrity, reliability and maintenance costs of communications networks. This paper defines best maintenance practices in communications network management within a concise framework encompassing measurable performance-level goals as well as methods and procedures needed to achieve these goals. The best maintenance practice recommendations of this paper cover many segments of communications networks and services, including wireline and wireless networks as well as multiple network spaces and technologies. The paper also outlines certain recent trends in network maintenance and provides specific recommendations for action to be taken to ensure that best network maintenance practices are implemented and maintained.
A component-based development framework for supporting functional and non-functional analysis in control system design
Authors: Johan Fredriksson, Massimo Tivoli, Ivica Crnkovic
Venue: Proceedings of the 20th IEEE/ACM international Conference on Automated software engineering (2005)

The use of component-based development (CBD) is growing in the software engineering community and it has been successfully applied in many engineering domains such as office applications and in web-based distributed applications. Recently, the need of CBD is growing also in other domains related to dependable and embedded systems, namely, in the control engineering domain. However, the widely used commercial component technologies are unable to provide solutions to the requirements of embedded systems as they require too much resources and they do not provide methods and tools for developing predictable and analyzable embedded systems. There is a need for new component-based technologies appropriate to development of embedded systems. In this paper we briefly present a component-based development framework called SAVEComp. SAVEComp is developed for safety-critical real-time systems. One of the main characteristics of SAVEComp is syntactic and semantic simplicity which enables a high analyzability of properties important for embedded systems. We discuss how SAVEComp is able to provide an efficient support for designing and implementing embedded control systems by mainly focusing on simplicity and analyzability of functional requirements and of real-time and dependability quality attributes. In particular we discuss the typical solutions of control systems in which feedback loops are used and which significantly complicate the design process. We provide a solution for increasing design abstraction level and still being able to reason about system properties using SAVEComp approach. Finally, we discuss an extension of SAVEComp with dynamic run-time property checking by utilizing run-time spare capacity that is normally induced by real-time analysis.
Study and Applications of Data Mining to the Structure Risk Analysis of Customs Declaration Cargo
Authors: Li Yan-hai, Sun lin-yan
Venue: Proceedings of the IEEE International Conference on e-Business Engineering (2005)

In order to solve the confliction between rapid increasing of cargo quantities and the Customs limited inspection force, a study and application of data mining is used in the structure risk analysis of customs declaration cargo. The cluster method of data mining is used in this paper to divide the cargo into seven types, thus customs can put the mainly inspection force to the high risk level cargo. The results show that this kind of method can be used to reform the operation mode of Customs inspection.
Template semantics: a parameterized approach to semantics-based model compilation
Authors: Jianwei Niu
Venue:  (2005)

This dissertation discusses a parameterized approach to the compiling of model-based notations into input languages of formal-analysis tools, based on descriptions of the notations' semantics. The semantics of a model-based notation is complex, and formalizing it in a semantics-description language, such as structural operational semantics and higher-order logic, can be challenging and error-prone. We propose a new approach, called template semantics, to structure the semantics of model-based specification notations. We demonstrate how to use template-semantics descriptions to construct notation-specific model compilers, which ease the mapping of new notations or notation variants to analysis tools. The basic computation model of template semantics is a non-concurrent, hierarchical transition system (HTS), whose execution semantics are parameterized. Semantics that are common among notations, e.g., the concept of an enabled transition are captured in the template, and a notation's distinct semantics, e.g., which events can enable transitions, are specified as parameters. HTSs can be combined by composition operators to form more complex, concurrent specifications. We provide the template semantics of seven composition operators and some of their variants; the operators define how multiple HTSs execute concurrently and how they communicate and synchronize with each other by exchanging events and data. The definitions of these operators use the template parameters to preserve notation-specific behaviour in composition. By separating a notation's step semantics from its composition operators, we simplify the definitions of both.
Will Proposed Standard Make Mobile Phones More Secure?
Authors: Neal Leavitt
Venue: Computer (2005)

The Trusted Computing Group is working on a set of specifications that would integrate data security into smart phones' core operations rather than implementing security via add-on applications.
Open data acquisition: theory and experiments
Authors: David G. Stork
Venue:  (2005)

Decades of research have pointed to the need for large datasets in building intelligent systems. While recent improvements in storage and other technologies have led to an explosion of available data, these raw data are often inadequate by themselves for machine learning, and additional human-provided information is necessary. For example, in natural language processing, optical character recognition, and speech recognition, raw data can be easily collected, but they need to be manually labeled in order to train the pattern classifiers. Unfortunately, acquisition of such manual data has not scaled at the exponential rate of information technologies, and it has become the economic bottleneck in building many pattern recognition systems. Open data acquisition attempts to scale up the collection of such manual data by leveraging volunteers openly through the Web. This dissertation addresses the challenges of open data acquisition from such non-expert contributors. We first address the oft-overlooked issue of evaluating classifiers using noisy labels, and we derive tight upper and lower bounds to the true error rate under mild assumptions. In analyzing the training and evaluation of classifiers using noisy labels, we found that for many problem domains the larger volume of data can compensate for the increase in labeling noise. Specifically, we found that challenging problem domains with naturally medium to high error rates can benefit the most from open data acquisition. Open data acquisition can be even more effective by optimizing its labeling strategy in the same spirit as active learning. We find that the information-theoretic optimal labeling strategy is to sometimes leave some data samples unlabeled yet have some data samples labeled by multiple contributors. The optimal labeling strategy also tends to assign difficult samples to more skillful labelers while easier samples to less skillful labelers. By leveraging the power of ordinary people through the Web, open data acquisition is a promising approach to alleviate the data bottleneck in building intelligent machines.
Optimal Surface Segmentation in Volumetric Images-A Graph-Theoretic Approach
Authors: Kang Li, Xiaodong Wu, Danny Z. Chen, Milan Sonka
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2006)

Efficient segmentation of globally optimal surfaces representing object boundaries in volumetric data sets is important and challenging in many medical image analysis applications. We have developed an optimal surface detection method capable of simultaneously detecting multiple interacting surfaces, in which the optimality is controlled by the cost functions designed for individual surfaces and by several geometric constraints defining the surface smoothness and interrelations. The method solves the surface segmentation problem by transforming it into computing a minimum s{\hbox{-}} t cut in a derived arc-weighted directed graph. The proposed algorithm has a low-order polynomial time complexity and is computationally efficient. It has been extensively validated on more than 300 computer-synthetic volumetric images, 72 CT-scanned data sets of different-sized plexiglas tubes, and tens of medical images spanning various imaging modalities. In all cases, the approach yielded highly accurate results. Our approach can be readily extended to higher-dimensional image segmentation.
Mass Flow Measurements based on a Virtual Channel Concept
Authors: D. Sankowski, V. Mosorov, K. Grudzien
Venue: Proceedings of the 5th International Conference on Intelligent Systems Design and Applications (2005)

The development of the mass flow rate measurements in the industrial systems using a twin-planes electrical capacitance tomography (ECT) system is presented. The mass flow measurement is based on cross-section decomposition into homogenous regions and virtual channel is then defined as connecting of two homogenous regions of different sensor planes. The decomposition has been obtained by using a stochastic flow model. As a result the set of virtual channels is obtained instead the complex flow inside a single physical channel. The authors present the results of investigation for turbulent flow propagation using the virtual channel concept also.
SLP-based service management for dynamic ad-hoc networks
Authors: Stefan Penz
Venue: Proceedings of the 3rd international workshop on Middleware for pervasive and ad-hoc computing (2005)

The need for an efficient service management system in an ad-hoc network is obvious. Mobile nodes -- and with them the services they provide -- frequently enter and leave the network, imposing comparatively high dynamics that have to be considered for the design of communication protocols on nearly any network layer. In this paper we propose an ad-hoc service management system based on the Service Location Protocol (SLP) that not only allows the user to discover appropriate service providers, but also keeps him informed about the existence and the properties of alternative providers. With this information the user application is able to prepare and conduct service handovers in case of network or device failures. Moreover, it becomes possible to change to a more convenient provider when one becomes available.