ppxscal/embedding_network huggingface dataset:
Adaptive Filter for Delay Line Combination (DLC) Receivers
Authors: Jyh-Horng Wen, Hsi-Chou Hsu
Venue: Proceedings of the Communication Networks and Services Research Conference (2008)

Delay Line Combination (DLC) receivers have been proposed for time hopping impulse radio ultra wideband (TH-IRUWB) systems by Wen and Hsu. In that study, we also presented a non-data aided synchronization algorithm designated as ”timing with delay line combination” (TDLC) algorithm. Although channel estimation is unnecessary for the DLC receivers, the system performance is affected by the setting of the integration window length (Tw). By tracking the variance of estimated timing offsets of the TDLC algorithm for each Tw setting, it’s found that the minimum variance is obtained at a best Tw setting. However,the best Tw setting is various in different channel environments. To optimize the system performance, for example mean square error (MSE) and bit error rate (BER) of the DLC receivers,we propose a non-data aided adaptive algorithm named ”leastvariance” (LV) adaptive algorithm to estimate the best Tw settingfor all channel environments.
Adaptive Multiuser Channel Estimation using Reduced Kalman/LMS Algorithm
Authors: Amit Kumar Kohli, D. K. Mehra
Venue: Wireless Personal Communications: An International Journal (2008)

This paper presents an adaptive multiuser channel estimator using the reduced-Kalman least-mean-square (RK-LMS) algorithm. The frequency-selective fading channel is modeled as a tapped-delay-line filter with smoothly time-varying Rayleigh distributed tap coefficients. The multiuser channel estimator based on minimum-mean-square-error (MMSE) criterion is used to predict the filter coefficients. We also present its convergence characteristics and tracking performance using the RK-LMS algorithm. Unlike the previously available Kalman filtering algorithm based approach (Chen, Chen IEEE Trans Signal Process 49(7): 1523---1532, 2001) the incorporation of RK-LMS algorithm reduces the computational complexity of multiuser channel estimator used in the code division multiple access wireless systems. The computer simulation results are presented to demonstrate the substantial improvement in its tracking performance under the smoothly time-varying environment.
Stylized black and white images from photographs
Authors: David Mould, Kevin Grant
Venue: Proceedings of the 6th international symposium on Non-photorealistic animation and rendering (2008)

Halftoning algorithms attempt to match the tone of an input image despite lower color resolution in the output. However, in some artistic media and styles, tone matching is not at all the goal; rather, details are either portrayed sharply or omitted entirely. In this paper, we present an algorithm for abstracting arbitrary input images into black and white images. Our goal is to preserve details while as much as possible producing large regions of solid color in the output. We present two methods based on energy minimization, using loopy belief propagation and graph cuts, but it is difficult to devise a single energy term that both sufficiently promotes coherence and adequately preserves details. We next propose a third algorithm separating these two concerns. Our third algorithm involves composing a base layer, consisting of large flat-colored regions, with a detail layer, containing the small high-contrast details. The base layer is computed with energy minimization, while local adaptive thresholding gives the detail layer. The final labeling is tidied by removing small components, vectorizing, and smoothing the region boundaries. The output images satisfy our goal of high spatial coherence with detail preservation.
SeeMon: scalable and energy-efficient context monitoring framework for sensor-rich mobile environments
Authors: Seungwoo Kang, Jinwon Lee, Hyukjae Jang, Hyonik Lee, Youngki Lee, Souneil Park, Taiwoo Park, Junehwa Song
Venue: Proceeding of the 6th international conference on Mobile systems, applications, and services (2008)

Proactively providing services to mobile individuals is essential for emerging ubiquitous applications. The major challenge in providing users with proactive services lies in continuously monitoring their contexts based on numerous sensors. The context monitoring with rich sensors imposes heavy workloads on mobile devices with limited computing and battery power. We present SeeMon, a scalable and energy-efficient context monitoring framework for sensor-rich, resource-limited mobile environments. Running on a personal mobile device, SeeMon effectively performs context monitoring involving numerous sensors and applications. On top of SeeMon, multiple applications on the device can proactively understand users' contexts and react appropriately. This paper proposes a novel context monitoring approach that provides efficient processing and sensor control mechanisms. We implement and test a prototype system on two mobile devices: a UMPC and a wearable device with a diverse set of sensors. Example applications are also developed based on the implemented system. Experimental results show that SeeMon achieves a high level of scalability and energy efficiency.
Percutaneous bone biopsy. A new application for 3D navigation: A pilot study
Authors: M. Citak, D. Kendoff, T. Wanich, A. Pearle, H. Wübben, C. Krettek, T. Hüfner
Venue: Technology and Health Care (2007)

Computer Tomography (CT) guided percutaneous bone biopsy has been established as a minimally invasive method for the rapidly obtaining samples from osseous lesions for histological examination. With this method, an overall accuracy of 90% can be obtained without a significant radiation exposure. The aim of this study was to develop a navigated sleeve for the Jamshidi needle in order to perform navigated, percutaneous bone biopsies with the help of Iso-C-3D. Utilizing this navigated biopsy needle, the procedure was analyzed for several parameters including precision, total operating time, and level of radiation exposure. By using the Iso-C-3D navigation the total operating time was 11.7 min (8-14.3) and radiation exposure was 1.6 (0.67-2.12 min). This study demonstrates that navigated percutaneous bone biopsies can be obtained fast and with low radiation exposure. The feasibility of Iso-C-3D navigated bone biopsies is tempered by the requirement a rigidly fixed dynamic reference frame.
The standards-based architecture of the adaptive learning environment aLFanet
Authors: Olga C. Santos, Jesus G. Boticario, Carmen Barrera
Venue: Proceedings of the 4th WSEAS International Conference on Applied Informatics and Communications (2004)

aLFanet (IST-2001-33288) aims to build an adaptive eLearning management system that provides personalised eLearning based on the combination of different types of adaptation (e.g. learning routes, interactions in services, peer-to-peer collaboration, presentation, questionnaires). It integrates new principles and tools in the fields of Learning Design and Artificial Intelligence, following existing standards in the educational field (IMS-LD, IMS-CP, IEEE-LOM, IMS-LIP, IMS-QTI), multi-agents systems (FIPA) and multiplatform communications (SOAP, XML, WebDav). This intensive use of standards makes aLFanet reusable in terms of contents, functionality, pedagogical designs and learners' profiles. On the one hand, this system is designed in a flexible and modular way, which facilitates the integration of third parties developments. On the other hand, despite the static adaptation specified by the course authors at design time, dynamic adaptation is also provided by the system on runtime. To achieve this, aLFanet includes a two level hierarchy of multi-agent architectures that works autonomously to solve the adaptation tasks required. It implements a hybrid approach to build the models needed for the adaptation tasks. This approach combines knowledge-based methods and machine learning techniques in a multi-agent architecture.
Matrix decomposition problem is complete for the average case
Authors: Y. Gurevich
Venue: Proceedings of the 31st Annual Symposium on Foundations of Computer Science (1990)

The first algebraic average-case complete problem is presented. The focus of attention is the modular group, i.e., the multiplicative group SL/sub 2/(Z) of two-by-two integer matrices of determinant 1. By default, in this study matrices are elements of the modular group. The problem is arguably the simplest natural average-case complete problem to date.
A framework based measurements for evaluating an IS quality
Authors: Olfa Lamouchi, Amar R. Cherif, Nicole Lévy
Venue: Proceedings of the fifth on Asia-Pacific conference on conceptual modelling - Volume 79 (2008)

There is an increasing community of researchers trying to draw attention to the importance of evaluation issues. Some approaches can be followed to evaluate the quality of software, but gives no guidance on how to construct a high quality software product and on how to use in practice this model across evaluation process. IS are built upon Software, and the quality of Software effects, if not determine the quality of the IS. There are several difficulties of developing a comprehensive model of IS quality. The concepts, models and measures that work in other fields might be usefully applied to the IS field, but careful analysis and consideration should be given. This paper describes a practical method that can be used to evaluate the expected quality of IS. Our approach is focused on a direct evaluation of the quality of an IS. Our proposed IS quality model is considered as structured set of properties (such as reliability, maintainability, and so on). These properties are usually presented as a hierarchy of statements. The uppermost ones represent the most general properties, suitable to be understood by the widest variety of people, but very difficult to measure directly. The deeper we sink into this hierarchy, the more technical-audience-oriented and measurable properties are found. These finals properties need to be measured using metrics. For this purpose a metrics measurement-based framework is linked to the defined quality model.
Une approche robuste pour la prolongation de la dur&eacute;e de vie des r&eacute;seaux ad hoc multim&eacute;dias
Authors: J. M. Bahi, M. Eskandar, A. Mostefaoui
Venue: Proceedings of the 4th French-speaking conference on Mobility and ubiquity computing (2008)

In wireless ad hoc networks, nodes are energy constrained. As they communicate far off destinations using intermediate relays, it may not be in interest of a node to expend its energy in relaying and consequently reducing its own lifetime. On the other hand, if all nodes decide not to always accept relay requests, the network throughput will drop dramatically i.e., the lifetime of the whole network is reduced. Obviously, from a single node point of view, these two extreme attitudes are opposite to its interest. We addressed this issue by proposing a novel distributed approach that guarantees tasks affectation to nodes with regard to their energy constraints. The key idea behind is to guarantee to all nodes that they share tasks in function of their energy provisions. In this paper, we tackle the problem of nodes mobility and its impact on the behavior of our proposed approach. We evaluated the performance of our approach under several scenrios and showed that it still improves the network lifetime.
Proceedings of the 2nd international workshop on Ultra-large-scale software-intensive systems
Venue: International Conference on Software Engineering (2008)

It is our great pleasure to welcome you to the 2nd International Workshop on Ultra-Large-Scale Software-Intensive Systems -- ULSSIS'08. This year's workshop continues to provide a forum for the software engineering research community to come together to discuss emerging ideas in the area of Ultra-Large-Scale (ULS) Systems. The primary goal of this workshop is to make progress toward a research agenda and a set of promising research directions for ULS systems, and to build an international research community in this area.
Distributed Reasoning for Context-Aware Services through Design of an OWL Meta-Model
Authors: S. Verstichel, M. Strobbe, P. Simoens, F. De Turck, B. Dhoedt, P. Demeester
Venue: Proceedings of the Fourth International Conference on Autonomic and Autonomous Systems (2008)

A growing number of applications start using Semantic Web technologies. The base concept in this technology is the use of ontologies, allowing first-order logic reasoning engines to execute a number of semantic tasks, such as the validation and consistence checking of the underlying ontology. Because applications work in a distributed environment, e.g. the retrieval of sensor values, resulting in ever increasing amounts of data, there is a clear need for this reasoning process to be distributed. Additional concepts to enable this distributed reasoning are therefore needed. In this paper, we present a meta-model based on the same Semantic Technology. To facilitate distributed reasoning, an architecture supporting this meta-model has been developed as well. The paper will show that the proposed solution offers significant improvement in terms of the reasoning process response times.
Another note on cliques and independent sets
Authors: Fred Galvin
Venue: Journal of Graph Theory (2000)

Entringer, Goddard, and Henning studied graphs in which every vertex belongs to both an (m&thinsp;+&thinsp;1)-clique and an independent (n&thinsp;+&thinsp;1)-set; they proved that there is such a graph of order p if and only if $p\geq m+n+\sqrt{4mn}$. We give an alternative and slightly easier proof of this fact, relating it to combinatorial matrix theory. &copy; 2000 John Wiley & Sons, Inc. J Graph Theory 35: 173&ndash;175, 2000
Vision: testing of mechatronics software using agile simulation
Authors: Stephen P. Masticola, Michael Gall
Venue: Proceedings of the 3rd international workshop on Automation of software test (2008)

Mechatronics is the practice of creating systems that synergize electrical, mechanical, and software technology. With few exceptions, testing software that is embedded in mechatronics systems has historically been done only with the hardware in the loop (HIL). There are many disadvantages to HIL testing, including cost, schedule delays, and resource bottlenecks. Ironically, cost and schedule delays are also often seen by technical managers as impediments to simulating the mechatronics hardware. We present a vision for agile simulation, with the intent to lower the cost and time barriers of simulating mechatronics hardware to test software. Some key ideas include: focus on validating the software alone, rather than the entire system; doing the minimum amount of dynamic modeling needed to test the software; work even with legacy systems that might not have been designed with testability in mind; leverage existing tools wherever possible; support stubbing out the hardware using agile techniques such as refactoring and test-driven development.
Convex hull covering of polygonal scenes for accurate collision detection in games
Authors: Rong Liu, Hao Zhang, James Busby
Venue: Proceedings of graphics interface 2008 (2008)

Decomposing a complex object into simpler pieces, e.g., convex patches or convex polyhedra, is a well-studied geometry problem. A well constructed decomposition can greatly accelerate collision detection since intersections with and between convex objects are fast to compute. In this paper, we look at a particular instance of the convex decomposition problem which arises from real-world game development. Given a collection of polyhedral surfaces (possibly with boundaries, holes, and complex interior structures) that model the scene geometry in a game environment, we wish to find a small set of convex hulls such that colliding objects in the scene against such a set of convex hulls produces the same game behavior as colliding against the original surfaces. The vague formulation of the problem is due to the difficulty of defining the space accessible by the objects involved in the game play. Under reasonable assumptions, we arrive at a set of conditions for valid convex decomposition and develop a construction algorithm via greedy merging driven by patch compactness. We show that our validity conditions ensure valid collision-related game behavior. The effectiveness of our decomposition algorithm is demonstrated through real examples from game development. To the best of our knowledge, no previous convex hull decomposition or surface decomposition algorithms were designed to handle the type of models we consider or be able to compute a set of convex hulls that ensure accurate collision detection results.
AI TURNS FIFTY: REVISITING ITS ORIGINS
Authors: Roberto Cordeschi
Venue: Applied Artificial Intelligence (2007)

The expression "artificial intelligence" (AI) was introduced by John McCarthy, and the official birth of AI is unanimously considered to be the 1956 Dartmouth Conference. Thus, AI turned fifty in 2006. How did AI begin? Several differently motivated analyses have been proposed as to its origins. In this paper a brief look at those that might be considered steps towards Dartmouth is attempted, with the aim of showing how a number of research topics and controversies that marked the short history of AI were touched on, or fairly well stated, during the year immediately preceding Dartmouth. The framework within which those steps were taken was the development of digital computers. Earlier computer applications in areas such as complex decision making and management, at that time dealt with by operations research techniques, were important in this story. The time was ripe for AI's intriguingly tumultuous development, marked as it has been by hopes and defeats, successes and difficulties.
Hardening XDS-Based Architectures
Authors: Kim Wuyts, Riccardo Scandariato, Geert Claeys, Wouter Joosen
Venue: Proceedings of the 2008 Third International Conference on Availability, Reliability and Security (2008)

Healthcare is an information-intensive domain and therefore information technologies are playing an evergrowing role in this sector. They are expected to increase the efficiency of the delivery of healthcare services in order to both improve the quality and reduce the costs. In this context, security has been identified as a priority although several gaps still exist. This paper reports on the results of assessing the threats to XDS-based architectures. Accordingly, an architectural solution to the identified threats is presented.
Using measurements to support real-option thinking in agile software development
Authors: Zornitza Racheva, Maya Daneva
Venue: Proceedings of the 2008 international workshop on Scrutinizing agile practices or shoot-out at the agile corral (2008)

This position paper applies real-option-theory perspective to agile software development. We complement real-option thinking with the use of measurements to support midcourse decision-making from the viewpoint of the client. Our position is motivated by using empirical data gathered from secondary sources.
SAVE: static analysis on versioning entities
Authors: Bastian Braun
Venue: Proceedings of the fourth international workshop on Software engineering for secure systems (2008)

Insufficiently tested software releases provoque a competition between 'exploiters' versus 'patchers'. Developing secure software from scratch greatly reduces maintenance effort. The integration of regular security checks combined with patch proposals at development time enhances the system's usability and software quality. This paper presents a software development system including version control, security analysis and patching support. As a practical aspect, avoiding flaws becomes easier even for non security experts.
Adaptation architectures cross levels
Authors: Yuanyuan Song, Devendra Rai, Kevin Sullivan
Venue: Proceedings of the 2nd international workshop on Ultra-large-scale software-intensive systems (2008)

To design ULS systems with the adaptive capacity they will need to be viable, requires that we broaden our understanding of software architecture. It is not just the software that must adapt, but the human-technical systems that produce and operate it. The traditional notion of an architecture as an abstract description of software artifacts and processes in an ontology of computational components, connections, and behavioral properties will not suffice. An alternative ontology based on decisions, decision-making tasks, agents, dependences among decisions, and the structure of such dependences appears to be worth exploring.
Hall's theorem for hypergraphs
Authors: Ron Aharoni, Penny Haxell
Venue: Journal of Graph Theory (2000)

We prove a hypergraph version of Hall's theorem. The proof is topological. &copy; 2000 John Wiley & Sons, Inc. J Graph Theory 35: 83&ndash;88, 2000
An Information Criterion for Variable Selection in Support Vector Machines
Authors: Gerda Claeskens, Christophe Croux, Johan Van Kerckhoven
Venue: The Journal of Machine Learning Research (2008)

Support vector machines for classification have the advantage that the curse of dimensionality is circumvented. It has been shown that a reduction of the dimension of the input space leads to even better results. For this purpose, we propose two information criteria which can be computed directly from the definition of the support vector machine. We assess the predictive performance of the models selected by our new criteria and compare them to existing variable selection techniques in a simulation study. The simulation results show that the new criteria are competitive in terms of generalization error rate while being much easier to compute. We arrive at the same findings for comparison on some real-world benchmark data sets.
Path smoothing via discrete optimization
Authors: Michael D. Moffitt, David A. Papa, Zhuo Li, Charles J. Alpert
Venue: Proceedings of the 45th annual Design Automation Conference (2008)

A fundamental problem in timing-driven physical synthesis is the reduction of critical paths in a design. In this work, we propose a powerful new technique that moves (and can also resize) multiple cells simultaneously to smooth critical paths, thereby reducing delay and improving worst negative slack or a figure-of-merit. Our approach offers several key advantages over previous formulations, including the accurate modeling of objectives and constraints in the true timing model, and a guarantee of legality for all cell locations.
An empirical Lotka-Volterra system for competition dynamics in the telecommunication sector of Sri Lanka
Authors: A. W. Wijeratne, J. A. Karunaratne, Chuncheng Wang, Junjie Wei
Venue: International Journal of Business Information Systems (2008)

The objective of the present research is to build an empirical Lotka-Volterra system using real-time data and information from two telecommunication service providers of Sri Lanka. The temporal change in market share of the two service providers was modelled by logistic population growth equation of which the coefficients were used as initial values to developing the competition system. Results show that the mobile telecom service providers and the fixed telephone service providers of Sri Lanka are in the process of reaching long-run stable coexistence equilibrium where they would own 83% and 17% shares of the market, respectively. The experimental procedure applied in the present research shows a path to linking mathematical models and economic theories with real-time information to build empirical models that address contemporary issues in life sciences for decision making.