ppxscal/embedding_network huggingface dataset:
Designing and analyzing collaboration in a scripted game for vocational education
Authors: Raija Hämäläinen, Kimmo Oksanen, Päivi Häkkinen
Venue: Computers in Human Behavior (2008)

This study attempts to combine the technological possibilities of 3D-game environments and collaborative learning scripts. The study is a design experiment (N=64) with multiple data collection and analysis (quantitative and qualitative) methods. The aims were twofold: The aim was to develop a game environment to simulate issues of work safety in a vocational context and to answer the following questions on the basis of an empirical study: (1) What kind of activities did the scripted game environment generate among the players? (2) How did the least and the most successful groups differ in this respect despite the same scripted game environment? Findings indicated that scripted game environment enriched the learning activities by enabling aspects that would not have been possible in traditional classroom settings. The scripted game environment also helped the players proceed in the different phases. However, the groups differed in terms of results in the test, collaboration processes, and the type and quantity of discussion. Especially discussion differed between the groups with highest and lowest test scores.
Correlations between the plates' vibrations from the guitar's structure and the physical, mechanical and elastically characteristics of the composite materials
Authors: Ioan Curtu, Mariana Domnica Stanciu, Raimond Grimberg
Venue: Proceedings of the 9th WSEAS International Conference on Acoustics & Music: Theory & Applications (2008)

Due to the acoustic, aesthetic and processing properties (workability, finishing, joints) the wood and the ligno-cellulose composites are the most valued materials for the musical instruments' construction. The guitar is made up of a complex structure, formed by a vertical wall in a curve shape (technologically named "sides") and two faces made up of ligno-cellulose plates, so that it should be formed an acoustic box which amplifies the vibrations of strings. The acoustic quality is determined by the contribution of each element (shape, dimensions, the nature of the used material, the characteristics of the excitation forces etc). This paper focuses on dynamical behaviour of every element and the whole structure. Firstly, the plates were considered simple, with different inner ribs, with various thicknesses and variable elasticity. Secondly, the plates were modelled as an assembly forming the body of guitar. It had been analyzed the structural behaviour of the plates under free and forced vibrations and also the acoustic box. The modelling with FEM permitted the emphasizing of some aspects, such as: the plate's and the box's normal modes of vibrations, the magnitude of the vibrations' amplitudes, reaching the resonance frequency at different values from the acoustic domain of the structure etc. The results obtained had been compared to the ones obtained by other researchers with analytical, numerical and experimental methods. The obtained data refer to the Romanian guitars produced at S. C. Hora S. A. Reghin.
Estimation of the Fracture Toughness of Soft Tissue from Needle Insertion
Authors: Toufic Azar, Vincent Hayward
Venue: Proceedings of the 4th international symposium on Biomedical Simulation (2008)

A fracture mechanics approach was employed to develop a model that can predict the penetration force during quasi-static needle insertion in soft tissue. The model captures a mechanical process where the sharp needle produces a crack that is opened to accommodate the shaft of the needle. This process involves the interchange of energy between four distinct phenomena: the work done by the needle, the irreversible work of fracture, the work of friction, and the change in recoverable strain energy. From measurements made in vivo, porcine liver fracture toughness was estimated from the difference in penetration force between two consecutive insertions at the same location. The values obtained fall within a reasonable range and confirm the relevance of a computational model of needle insertion based on fracture mechanics.
Epistemological and Ontological Representation in Software Engineering
Authors: J. Cuadrado-Gallego, D. Rodríguez, M. Garre, R. Rejas
Venue: Proceedings of the 7th international conference on Computational Science, Part II (2007)

This paper provides an overview of how empirical research can be a valid approach to improve epistemological foundations and ontological representations in Software Engineering (SE). Despite of all the research done in SE, most of the results have not been yet been stated as laws, theories, hypothesis or conjectures, i.e., from an epistemological point of view. This paper explores such facts and advocates that the use of empirical methods can help to improve this situation. Furthermore, it is also imperative for SE experiments to be planned and executed properly in order to be valid epistemologically. Finally, this paper presents some epistemological and ontological results obtained from empirical research in SE.
Color Photo Denoising Via Hue, Saturation and Intensity Diffusion
Authors: Lei He, Chenyang Xu
Venue: Proceedings of the 5th international conference on Image Analysis and Recognition (2008)

This paper presents a new image denoising model for color photo noise removal. Unlike previous approaches, our algorithm is based on separating a color photo into hue, saturation, and intensity (HSI) components, and then processing each component with partial differential equations (PDE)-based diffusion flows. The hue and saturation denoising are implemented by a new weighted orientation diffusion and a modified curvature flow respectively. The intensity denoising is implemented with a PDE that is a combination of a gradient vector flow (GVF)-based filter and a fourth-order PDE filter. This combined technique provides a robust and accurate denoising process, i.e., it preserves edges well and at the same time overcomes the staircase effect in smooth regions. Experiments on color photos demonstrate the improved performance of the proposed model when compared with other recognized approaches and commercial software.
Reutilization of Partial LU Factorizations for Self-adaptive hp Finite Element Method Solver
Authors: Maciej Paszynski, Robert Schaefer
Venue: Proceedings of the 8th international conference on Computational Science, Part I (2008)

The paper presents theoretical analysis of the extension of the new direct solver dedicated for the fully automatic hp adaptive Finite Element Method. The self-adaptive hp-FEM generates in a fully automatic mode (without any user interaction) a sequence of meshes delivering exponential convergence of the numerical error with respect to the mesh size. The consecutive meshes are obtained by performing h, p or hp refinements. The proposed solver constructs an initial elimination tree based on the nested dissection algorithm executed over the initial mesh. The constructed elimination tree is updated each time the mesh is refined, by adding the elimination sub-tree related to the executed refinement. We propose a new strategy for reutilization of partial LU factorizations computed by the direct solver on the previous mesh, when solving a consecutive mesh from the sequence. We show that the number of LU factorizations that must be recomputed is linearly proportional to the number of singularities in the problem.
XML-Based Multi-agent Communication System Architecture
Authors: Longzhen Duan, Guang Zeng, Longjun Huang, Yuhua Feng
Venue: Proceedings of the 2008 Second International Conference on Genetic and Evolutionary Computing (2008)

Interactivity is the focus of the study in multi-agent system, and Agent Communication Language (ACL) is the base of interactivity and cooperation. Under the current environment of agent, the current mainstream communication language KQML and the shortcomings of the associate content language are analyzed. With the mainstream technology XML in WWW, the integration method between the XML language and KQML is proposed and on this basis, an XML-based agent communication architecture is designed to improve the efficiency of communication between agents.
Towards Heterogeneous Similarity Function Learning for the k-Nearest Neighbors Classification
Authors: Karol Grudziński
Venue: Proceedings of the 9th international conference on Artificial Intelligence and Soft Computing (2006)

In order to classify an unseen (query) vector q with the k-Nearest Neighbors method (k-NN) one computes a similarity function between q and training vectors in a database. In the basic variant of the k-NN algorithm the predicted class of q is estimated by taking the majority class of the q's k-nearest neighbors. Various similarity functions may be applied leading to different classification results. In this paper a heterogeneous similarity function is constructed out of different 1-component metrics by minimization of the number of classification errors the system makes on a training set. The HSFL-NN system, which has been introduced in this paper, on five tested datasets has given better results on unseen samples than the plain k-NN method with the optimally selected k parameter and the optimal homogeneous similarity function.
Extraction and representation of prosodic features for language and speaker recognition
Authors: Leena Mary, B. Yegnanarayana
Venue: Speech Communication (2008)

In this paper, we propose a new approach for extracting and representing prosodic features directly from the speech signal. We hypothesize that prosody is linked to linguistic units such as syllables, and it is manifested in terms of changes in measurable parameters such as fundamental frequency (F"0), duration and energy. In this work, syllable-like unit is chosen as the basic unit for representing the prosodic characteristics. Approximate segmentation of continuous speech into syllable-like units is obtained by locating the vowel onset points (VOP) automatically. The knowledge of the VOPs serve as reference for extracting prosodic features from the speech signal. Quantitative parameters are used to represent F"0 and energy contour in each region between two consecutive VOPs. Prosodic features extracted using this approach may be useful in applications such as recognition of language or speaker, where explicit phoneme/syllable boundaries are not easily available. The effectiveness of the derived prosodic features for language and speaker recognition is evaluated in the case of NIST language recognition evaluation 2003 and the extended data task of NIST speaker recognition evaluation 2003, respectively.
Student Modelling Based on Belief Networks
Authors: Jim Reye
Venue: International Journal of Artificial Intelligence in Education (2004)

Belief networks provide an important way to represent and reason about uncertainty - significant factors for modelling students. These networks provide a way of structuring such models, and allow a system to use a systematic approach when gathering information about the scope of the student's knowledge. This work also provides a theoretically-sound way to update the student model, based on the concept of a dynamic belief network. The relationship to related research is discussed. Finally, the paper describes why the barren node concept is important for computational efficiency in belief-net-based student models.
The Objects and Arrows of Computational Design
Authors: Don Batory, Maider Azanza, João Saraiva
Venue: Proceedings of the 11th international conference on Model Driven Engineering Languages and Systems (2008)

Computational Design (CD) is a paradigm where both program design and program synthesis are computations. CD merges Model Driven Engineering (MDE) which synthesizes programs by transforming models, with Software Product Lines (SPL) where programs are synthesized by composing transforma tions called features. In this paper, basic relationships between MDE and SPL are explored using the language of modern mathematics.Note: Although jointly authored, this paper is written as presented by Batory in his MODELS 2008 keynote.
Placement of multiple mobile data collectors in underwater acoustic sensor networks
Authors: Waleed Alsalih, Hossam Hassanein, Selim Akl
Venue: Wireless Communications Mobile Computing (2008)

We propose two schemes for routing and placement of mobile data collectors in underwater acoustic sensor networks (UASNs): the delay tolerant placement and routing (DTPR) and the delay constrained placement and routing (DCPR). As their names reveal, while the DTPR maximizes the lifetime of the network without any delay considerations, the DCPR maximizes the lifetime of the network with an upper bound on the maximum delay. Both schemes are based on a 3D architecture, in which on-the-surface data collectors gather data from underwater sensors and relay them to an on-shore sink. We divide the lifetime of the network into fixed length rounds and move the data collectors to new locations at the beginning of each round. These problems are formulated as integer linear programs (ILPs), and we use an ILP solver to find the optimal placement of data collectors together with the multi-hop routing paths to deliver data from underwater sensors to data collectors. Our work is a pioneering effort in the placement of mobile data collectors in three-dimensional UASNs. Comprehensive experiments show that our schemes prolong the lifetime of the network significantly as compared to other data collector placement schemes. Copyright &copy; 2008 John Wiley & Sons, Ltd.
Adaptive Dynamic Reaction to Automotive IT Security Incidents Using Multimedia Car Environment
Authors: Tobias Hoppe, Stefan Kiltz, Jana Dittmann
Venue: Proceedings of the 2008 The Fourth International Conference on Information Assurance and Security (2008)

Modern cars offer an increasingly powerful Multimedia environment. While also the potential for an application as Human Computer Interface (HCI) is growing, in this paper we concentrate on already existing possibilities for their use as Computer-Human-Interface (CHI) to communicate system security related information to the driver.After identifying the Intrusion Detection approach from desktop IT as a promising supplemental measure for the IT security of future automotive systems and successfully testing it in practice, in this paper we investigate about how such an automotive Intrusion Detection System (IDS) could communicate security-related information to the driver. We propose an adaptive dynamic concept to address the frequently changing environmental conditions in the automotive domain and discuss it using three exemplarily selected scenarios.
An Architecture-Centric Development Environment for Black-Box Component-Based Systems
Authors: Gerald Kotonya
Venue: Proceedings of the 2nd European conference on Software Architecture (2008)

Component-based software system development typifies traditional engineering philosophy by promoting the construction of systems from pre-fabricated software components. Underlying this philosophy is the promise of accelerated, low cost development and reliable software systems. However, the development strategy is hampered by the lack of practical methods and tools that support the reuse-driven paradigm embodied in black-box components. Current methods and tool environments provide poor support for the challenges posed by developing systems from off-the-shelf black-box components. These include poor support for: component discovery and verification, modelling and mapping requirements to component architectures, negotiation, architectural design and composition, and managing change. This paper describes an architecture-centric approach and environment for formulating, integrating and deploying black-box component-based systems. Practical experience of using the approach is illustrated with a real case study.
Fast track article: Exploiting users' social relations to forward data in opportunistic networks: The HiBOp solution
Authors: Chiara Boldrini, Marco Conti, Andrea Passarella
Venue: Pervasive and Mobile Computing (2008)

Opportunistic networks, in which nodes opportunistically exploit any pair-wise contact to identify next hops towards the destination, are one of the most interesting technologies to support the pervasive networking vision. Opportunistic networks allow content sharing between mobile users without requiring any pre-existing Internet infrastructure, and tolerate partitions, long disconnections, and topology instability in general. In this paper we propose a context-aware framework for routing and forwarding in opportunistic networks. The framework is general, and able to host various flavors of context-aware routing. In this work we also present a particular protocol, HiBOp, which, by exploiting the framework, learns and represents through context information, the users' behavior and their social relations, and uses this knowledge to drive the forwarding process. The comparison of HiBOp with reference to alternative solutions shows that a context-aware approach based on users' social relations turns out to be a very efficient solution for forwarding in opportunistic networks. We show performance improvements over the reference solutions both in terms of resource utilization and in terms of user perceived QoS.
Learn while you earn: two approaches to learning auction parameters in take-it-or-leave-it auctions
Authors: Archie C. Chapman, Alex Rogers, Nicholas R. Jennings
Venue: Proceedings of the 7th international joint conference on Autonomous agents and multiagent systems - Volume 3 (2008)

Much of the research in auction theory assumes that the auctioneer knows the distribution of participants' valuations with complete certainty. However, this is unrealistic. Thus, we analyse cases in which the auctioneer is uncertain about the valuation distributions; specifically, we consider a repeated auction setting in which the auctioneer can learn these distributions. Using take-it-or-leave-it auctions (Sandholm and Gilpin, 2006) as an exemplar auction format, we consider two auction design criteria. Firstly, an auctioneer could maximise expected revenue each time the auction is held. Secondly, an auctioneer could maximise the information gained in earlier auctions (as measured by the Kullback-Liebler divergence between its posterior and prior) to develop good estimates of the unknowns, which are later exploited to improve the revenue earned in the long-run. Simulation results comparing the two criteria indicate that setting offers to maximise revenue does not significantly detract from learning performance, but optimising offers for information gain substantially reduces expected revenue while not producing significantly better parameter estimates.
Cost Analysis of Current Grids and Its Implications for Future Grid Markets
Authors: Marcel Risch, Jörn Altmann
Venue: Proceedings of the 5th international workshop on Grid Economics and Business Models (2008)

Commercial Grid markets have been a topic of research for many years. Many claims about the advantages of trading computing resources on markets have been made. However, due to a lack of Grid computing offerings, these claims could not be verified. This paper analyzes the question whether using the Grid is financially advantageous, using the Amazon.com EC2 service as a reference. To perform this analysis, the costs of computing resources in different usage scenarios are calculated, if Grid resources and in-house resources are used. The comparison of the costs reveals that while the Grid is cheaper in the short term, it is not a good investment in the long term and, thus, the existence of a Grid economy will not lead to an end of ownership but rather to a reduction in in-house resources and more efficient resource usage.
Automated unit testing intelligent agents in PDT
Authors: Zhiyong Zhang, John Thangarajah, Lin Padgham
Venue: Proceedings of the 7th international joint conference on Autonomous agents and multiagent systems: demo papers (2008)

The Prometheus Design Tool (PDT) is an agent development tool that supports the Prometheus design methodology and includes features like automated code generation. We enhance this tool by adding a feature that allows the automated unit testing of agents that are built from within PDT.
Discontinuous feedback linearization sliding mode control of a synchronous generator machine and hydraulic turbine
Authors: David Hernández-Torres, Alberto J. Urdaneta
Venue: Proceedings of the 10th WSEAS International Conference on Automatic Control, Modelling & Simulation (2008)

A novel robust control technique is proposed for the control of synchronous machines operating in electric power systems. The Sliding Mode Control technique belongs to the Variable Structure Systems Theory. The control law used is unique, non-linear and besides, it is discontinuous. Its discontinuous nature allows the controller to enhance the robustness of the system; which means that the control is insensitive to model uncertainties as well as to external disturbances. The sliding mode control approach is applied together with the Feedback Linearization technique, which is used here to obtain a decoupled-reduced form of the system in terms of the output controlled variables and the control input. Two different control schemes using sliding mode control are proposed and applied to synchronous machines. The response is obtained using a complete high order model for the machine, taking in consideration the model of the hydraulic turbine. The analysis of the obtained results show that in both cases the system response to small as well as to large disturbances, show a significant advantage of the proposed control techniques over conventional linear control systems for the Automatic Voltage Regulation (AVR) and the Power System Stabilizer (PSS). Moreover, the analysis of the system response to parameter variations demonstrates the robust characteristic of the non-linear discontinuous controller. The advantages obtained with sliding mode control appear directly in the operational behavior of the system as a substantial improvement in the stability characteristics of the electric power system.
Trustworthy Digital Long-Term Repositories: The Nestor Approach in the Context of International Developments
Authors: Susanne Dobratz, Astrid Schoger
Venue: Proceedings of the 11th European conference on Research and Advanced Technology for Digital Libraries (2007)

This paper describes the general approach nestor --- the German "Network of Expertise in Long-Term Storage of Digital Resources" has taken in designing a catalogue of criteria for trustworthy digital repositories for long-term preservation and how this approach relates to internationalisation and standardisation of criteria and developments of evaluation methods to facilitate the audit and certification process.
On the Use of Symbolic Data Analysis to Model Communication Environments
Authors: Flavien Balbo, Julien Saunier
Venue: Proceedings of the 12th international workshop on Cooperative Information Agents XII (2008)

Recent research on multi-party communications shows how multi-agent communications can take advantage of the complexity of the human communication process. The salient point is the very nature of the communication channels which enable humans to focus their attention on ambient communications, as well as to direct their own communications. For multi-agent systems, the difficulty is the routing of messages according to both the needs of the sender and the needs of the (potential) recipients . This difficulty is compounded by the necessity of taking into account the context of this communication. This article proposes an architecture for the Environment as Active Support for Interaction model (EASI) which is based on a classification data model and supports multiparty communication. Our proposition has been implemented and the functional description of the environment is given.