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The objective of this research was to develop, assess and validate alternative boom designs that would allow containment and collection of oil spills in water at higher speeds than currently possible using conventional boom technologies. A comprehensive series of two- and three-dimensional CFD simulations and large-scale physical model experiments were conducted investigating the oil containment performance characteristics of several innovative boom concepts (and multiple variations thereof) at high speeds. Both the simulations and experiments considered varying quantities of low, medium, and high-viscosity oils. This paper discusses the physical scale model experiments in detail. The boom concepts investigated in this research included conventional designs with a single skirt and innovative designs incorporating ramps or permeable screen barriers to manage the oil slick at higher speeds. The extensive laboratory testing and computational modelling revealed that innovative boom designs are able to safely and effectively contain oil at speeds up to 3 knots or more. Effective high-speed booms will make it possible to contain and recover oil spilled into fast-flowing rivers, estuaries and coastal waters, and accelerate oil recovery operations in open water environments., 43rd AMOP Technical Seminar on Environmental Contamination and Response 2021, June 8-10, 2021, Virtual, Online, Canada

Existing relational database systems often suffer from rapid increases or significant variability of transactional workloads but lack support for scalability or elasticity. Database replication has been employed to scale workload performance but past approaches make various performance versus consistency tradeoffs and typically lack the mechanisms and policies for dynamically adding and removing replicas. This paper presents Hihooi, a replication-based middleware system that is able to achieve scalability, strong consistency, and elasticity for existing transactional databases. These features are enabled by (i) a novel replication algorithm for propagating database modifications asynchronously and consistently to all replicas at high speeds, and (ii) a new routing algorithm for directing incoming transactions to consistent replicas. Our experimental evaluation validates the high scalability and elasticity benefits offered by Hihooi, which form the key ingredients towards a truly auto-scaling system.

The vocational-technical education (V-TE) system has started a restructuring process recently especially in developing countries. In this study, the awareness level for renewable energy sources of individuals related with V-TE is investigated. Awareness survey for renewable energy sources is applied among the participants who are subdivided to different groups with respect to their gender, role in V-TE system and educational-social status. There is no statistically significant difference observed with respect to gender according to the results; (t((138)) = 0.027, p = 0.978 > 0.05). The participants are investigated in 5 different groups as "students in the Department of Electric and Energy (DEE) in Vocational School (VS)", "graduates from DEE in VS", "students in VS", "graduates from VS" and "parents of the students in VS". According to the One-Way ANNOVA test results (F-(4,F-135)=4.402, p = 0.002

The objective of the study was to test several bristle materials, which are designed for arctic brush skimmers, and find out the possible differences in their performance with two different oil type and in three temperatures. Additional objective was to clarify the possible correlation between the results from Wilhelmy plate experiments and macro-scale test results. The tests were performed in the collaboration with VTT and SYKE. Two test drums from both bristle materials were manufactured for the macro scale tests, one for marine diesel oil and one for heavy fuel oil. The design of the drums and bristles were predefined to enable the comparison of the results. The test program was two-fold; in the first phase totally 11 different materials were tested with the Wilhelmy plate method in order to determine the surface tension of the particular test oil with the bristle materials. According to the Wilhelmy plate measurements, two materials were selected for the macro-scale tests. The tests were carried out according to a specific test program particularly prepared for the macro-scale tests. All the tests were performed without water or ice, and depending on the oil type and temperature, each test was repeated 5 or 10 times. The results indicated that the differences in the oil pick-up rates were smaller with heavy fuel oil than with marine diesel oil, and different materials had diverse trends in the variation of the pick-up rates between the test runs. In addition, the correlation between the Wilhelmy plate experiments and the macro scale tests could be observed.

The objective of the study was to test several bristle materials, which are designed for arctic brush skimmers, and find out the possible differences in their performance with two different oil type and in three temperatures. Additional objective was to clarify the possible correlation between the results from Wilhelmy plate experiments and macro-scale test results. The tests were performed in the collaboration with VTT and SYKE. Two test drums from both bristle materials were manufactured for the macro scale tests, one for marine diesel oil and one for heavy fuel oil. The design of the drums and bristles were predefined to enable the comparison of the results. The test program was two-fold; in the first phase totally 11 different materials were tested with the Wilhelmy plate method in order to determine the surface tension of the particular test oil with the bristle materials. According to the Wilhelmy plate measurements, two materials were selected for the macro-scale tests. The tests were carried out according to a specific test program particularly prepared for the macro-scale tests. All the tests were performed without water or ice, and depending on the oil type and temperature, each test was repeated 5 or 10 times. The results indicated that the differences in the oil pick-up rates were smaller with heavy fuel oil than with marine diesel oil, and different materials had diverse trends in the variation of the pick-up rates between the test runs. In addition, the correlation between the Wilhelmy plate experiments and the macro scale tests could be observed.

In this work we present some guidelines and advices concerning preparation, presentation and writing of scientific and technical texts. Particular attention is given to college level reports. Some principles and effective examples are given.

This paper presents the findings from a study conducted to explore the current and future use of information visualization (IV) for digital libraries (DL). A series of query techniques and participatory design workshops were employed with the goal of actively involving users in identifying the key characteristics and applications of IV for DLs. The methodology employed, key findings and overall conclusions are presented and discussed.

Date of Conference: 9-12 Sept. 2014 Conference name: 43rd International Conference on Parallel Processing Workshops, 2014 The 1st International Workshop on High Performance Computing for Big Data (HPC4BD) is held on September 10, 2014 in concordance with 43rd International Conference on Parallel Processing (ICPP-2014). The workshop aimed to bring high performance computing (HPC) experts and experts from various application domains together to discuss their Big Data problems. There were four works accepted to be presented in this year's workshop. This foreword presents a summary of the them. © 2014 IEEE.

Engineering syllabi often lack courses covering occupational risk prevention. In Spain, professional competences are awarded along with the completion of a university degree. This means that new graduates are certified in areas in which they have received little or no training, such as occupational risk prevention. However, the academic reforms established by the Bologna Process, which strives to homogenize university degrees throughout Europe, compels European universities to design new syllabi. The main goal of this paper is to define a framework for including occupational risk-prevention education in the new engineering syllabi. This exploratory research applied the Delphi methodology to a panel of 59 experts, using questionnaires assessed with a four-point Likert scale through two rounds. A website supported the information flow. According to the experts who participated in this study, education and training in occupational risk-prevention is essential for improving the safety culture within a company or workplace. The experts concurred that this subject should be a separate mandatory course in all engineering degree programs. The participants recommended that an optional course should be considered only if a mandatory course is not approved. It was also deemed desirable to integrate occupational risk prevention as a cross-field subject in other technological courses, even if the curriculum already includes some related courses. © 2012 American Society of Civil Engineers.

In view of depleting fossil fuel resources and environmental concern, biodiesel couldpotentially replace petroleum-derived diesel. Aquatic toxicity of diesel and biodiesel has beenextensively studied over the past decades but little is still known about their toxicity in soilenvironment. The scope of this study was to evaluate the environmental impact of biodiesel,biodiesel blends and petroleum diesel in soil using direct contact toxicity assays. The selectedbiodiesels included canola-source biodiesel (B100 and B20). and tallow-source biodiesel (B100and B20), which were compared to petroleum ultra-low-sulfur based diesel (ULSD). Selectedstandard terrestrial toxicity tests included ryegrass Lolium perenne seedling emergence andgrowth, earthworm Eisenia fetida survival, and soil microbial dehydrogenase activity. Soilcharacterization included the quantification of total extractable materials (corresponding to the n-alkane range of C10-C34). Preliminary results indicate that: 1) canola and tallow B20 biodieselblends were less toxic to earthworm than ULSD; 2) canola and tallow B20 blends had similartoxic effects to ryegrass as ULSD; and 3) petroleum ULSD inhibited the DHA activity at allconcentrations tested, and B20 canola biodiesel had a deleterious effect on the DHA activity atthe lowest nominal loadings tested (1 and 10 ml/kg dry soil). Therefore, this study providesuseful toxicological data for the evaluation of potential adverse impact of biodiesel in theenvironment, such as an accidental release or spill. This project was funded by EnvironmentCanada and Natural Resources Canada and is part of the Advanced Fuels and Technologies forEmissions Reduction (AFTER) Program for energy research and development (PERD)., 35th AMOP Technical Seminar on Environmental Contamination and Response, 5 June 2012 through 7 June 2012, Vancouver, BC

Date of Conference: 15-18 Aug. 2011 Global Software Development (GSD) can be considered as the coordinated activity of software development that is not localized and central but geographically distributed. Designing an appropriate software architecture of a GSD system is important to meet the requirements for the communication, coordination and control of the distributed GSD teams. A common practice in software architecture design is to apply architectural views to model the design decisions for the various stakeholder concerns. Unfortunately, existing architectural viewpoint approaches are general-purpose and not directly dedicated towards GSD projects. In this paper we propose six architectural viewpoints that have been specifically defined to model GSD systems. The architectural viewpoints are based on a meta-model that has been derived after a thorough domain analysis of the GSD literature. © 2011 IEEE.

The CoMetS workshop aims to bring together leading researchers and practitioners from both the modeling and simulation (M&S) community and the collaborative environments community, in order to focus on innovative research contributions that address both the use of collaborative technologies in the field of M&S and the use of M&S methodologies and tools to address the design of collaborative systems. This paper reports on the motivations of the workshop and the organization of its first edition.

The growing importance of wireless communications has been driving the research and development of advanced network architectures to enable the cost-effective support of large numbers of users at very high data rates. In this context, the FUTON project aims to fulfil the objectives of the so-called 4th Generation (4G) wireless communications through an innovative Distributed Antenna System (DAS) with centralized signal processing. An overview of the FUTON concept is presented in this paper, with emphasis on the optical link design for radio-over-fiber communication providing the virtual-MIMO functionalities between multiple remote antenna units with a centralized processing site. Also, the units being fabricated for the final demonstration are described, and some preliminary measurements are presented. © 2010 IEEE.

A planar antenna that utilize surface waves (SWs) for leaky wave (LW) excitation is investigated. Specifically, a surface-wave launcher (SWL) is employed to excite cylindrical SWs which are bound to a grounded dielectric slab (GDS). By the addition of a grid of width-modulated printed strips, a high impedance surface (HIS) can be realized, providing appropriate conditions for LW radiation. A planar metallic grating lens is also included in the design of the antenna to achieve in phase leakage along the aperture. Far field beam pattern results suggest one-sided beam scanning between 22 and 24 GHz with reflection losses below 10 dB and gain values of 8.7 dBi at broadside. Such a printed or planar low-cost and low-profile LWA may be advantageous for radar systems and satellite communications.

In this paper we focus on explaining to humans the behavior of autonomous agents, i.e., explainable agents. Explainable agents are useful for many reasons including scenario-based training (e.g. disaster training), tutor and pedagogical systems, agent development and debugging, gaming, and interactive storytelling. As the aim is to generate for humans plausible and insightful explanations, user evaluation of different explanations is essential. In this paper we test the hypothesis that different explanation types are needed to explain different types of actions. We present three different, generically applicable, algorithms that automatically generate different types of explanations for actions of BDI-based agents. Quantitative analysis of a user experiment (n=30), in which users rated the usefulness and naturalness of each explanation type for different agent actions, supports our hypothesis. In addition, we present feedback from the users about how they would explain the actions themselves. Finally, we hypothesize guidelines relevant for the development of explainable BDI agents. © 2010 Springer-Verlag Berlin Heidelberg.

In this paper we focus on explaining to humans the behavior of autonomous agents, i.e., explainable agents. Explainable agents are useful for many reasons including scenario-based training (e.g. disaster training), tutor and pedagogical systems, agent development and debugging, gaming, and interactive storytelling. As the aim is to generate for humans plausible and insightful explanations, user evaluation of different explanations is essential. In this paper we test the hypothesis that different explanation types are needed to explain different types of actions. We present three different, generically applicable, algorithms that automatically generate different types of explanations for actions of BDI-based agents. Quantitative analysis of a user experiment (n=30), in which users rated the usefulness and naturalness of each explanation type for different agent actions, supports our hypothesis. In addition, we present feedback from the users about how they would explain the actions themselves. Finally, we hypothesize guidelines relevant for the development of explainable BDI agents. © 2010 Springer-Verlag Berlin Heidelberg.

We establish a surprisingly close relationship between universal Horn classes of directed graphs and varieties generated by so-called adjacency semigroups which are Rees matrix semigroups over the trivial group with the unary operation of reversion. In particular, the lattice of subvarieties of the variety generated by adjacency semigroups that are regular unary semigroups is essentially the same as the lattice of universal Horn classes of reflexive directed graphs. A number of examples follow, including a limit variety of regular unary semigroups and finite unary semigroups with NP-hard variety membership problems., 30 pages, 9 figures

In cognitive radio systems, secondary users can utilize multiple dispersed bands that are not used by primary users. In this paper, time delay estimation of signals that occupy multiple dispersed bands is studied. First, theoretical limits on time delay estimation are reviewed. Then, two-step time delay estimators that provide trade-offs between computational complexity and performance are investigated. In addition, asymptotic optimality properties of the two-step time delay estimators are discussed. Finally, simulation results are presented to explain the theoretical results., To appear at CAMSAP 2009

Information Hovering is a relatively new concept of information dissemination over a mobile set of peers. It naturally applies in many applications in Vehicular Ad-Hoc Networks, where useful information needs to be made available to all vehicles within a confined geographical area for a specific time interval. A straightforward approach, is to have all vehicles within the hovering area exchange messages with each other. However, this method does not guarantee that all vehicles within the hovering area will receive the message due to potential partitioning of the network in areas with low traffic density and/or low market penetration rate. In this work, we address the problem by applying probabilistic flooding schemes outside the hovering area. Informed vehicles outside the hovering area can serve as information bridges towards partitioned uninformed areas thus leading to high reachability.We consider a number of rebroadcast probability functions and we evaluate their performance using the microscopic simulation tool VISSIM. Our reference model represents a section of the road network in the cities of Bellevue and Redmond in Washington. The obtained results indicate that probabilistic flooding with a Gaussian like probability function outperforms other approaches by achieving high reachability values and a relatively small number of exchanged messages. © 2009 IEEE. Conference code: 79889 Cited By :6

Conference name: 2009 International Workshop Terahertz and Mid Infrared Radiation: Basic Research and Practical Applications Date of Conference: 3-6 November 2009 We review two metamaterial configurations, which are operating at the millimeter-wave scale, in terms of design, fabrication, and characterization. We observed both numerically and experimentally at around 100 GHz a narrow frequency band for which the metamaterial was low loss and had a negative index of refraction. We investigated flat and wedge shaped samples to support our characterization results. We analyzed the transmission band with respect to number of layers at the propagation direction and commented on the bulk nature of these metamaterials. Oblique response of the planar sample was also included in this study. Finally, we demonstrate a device, which yields a rather small angular width at the far field radiation pattern, and composed of a horn antenna and flat metamaterial slabs at the propagation direction. ©2009 IEEE.

IPAC (Integrated Platform for Autonomic Computing) aims at delivering a middleware and service creation environment for developing embedded, intelligent, collaborative, context-aware services in mobile nodes. IPAC relies on short range communications for the ad hoc realization of dialogs among collaborating nodes. Advanced sensing components leverage the context-awareness attributes of IPAC, thus rendering it capable of delivering highly innovative applications for mobile and pervasive computing. IPAC networking capabilities are based on rumour spreading techniques, a stateless and resilient approach, and information dissemination among embedded nodes. Spreading of information is subject to certain rules (e.g., space, time, price). IPAC nodes may receive, store, assesses and possibly relay the incoming content to other nodes. The same distribution channel is followed for the dissemination of new applications and application components that "join the IPAC world". © 2009 IEEE. Conference code: 78373 Cited By :1

Designing specifications for technically advanced instructional products, such as e-learning, simulations or simulators requires different kinds of expertise. The SLIM method proposes to involve all stakeholders from the beginning in a series of workshops under the guidance of experienced instructional designers. These instructional designers ensure that specifications are designed in a systematic, iterative, way based on instructional design and development models. The workshop participants, however, bring in all the necessary information and they take all the decisions. The SLIM method is geared towards the first phase of the instructional design process: designing a needs statement in the form of a first set of global user requirements. It has been used in eight case studies. The results of these case studies have led to improvements to the method and suggestions for further research. 1. Introduction 2. Problem and setting 3. Basic principles underlying the SLIM method 4. The SLIM method 4.1. Research questions 5. Case studies: method 5.1. Procedure 5.2. The cases 6. Case studies: results 6.1. Development of adequate needs statements 6.2. Iteration 6.3. The required amount of time 6.4. The number and kind of participants 6.5. The role of facilitators 7. Conclusions and recommendations 8. Future work Acknowledgements References

Designing specifications for technically advanced instructional products, such as e-learning, simulations or simulators requires different kinds of expertise. The SLIM method proposes to involve all stakeholders from the beginning in a series of workshops under the guidance of experienced instructional designers. These instructional designers ensure that specifications are designed in a systematic, iterative, way based on instructional design and development models. The workshop participants, however, bring in all the necessary information and they take all the decisions. The SLIM method is geared towards the first phase of the instructional design process: designing a needs statement in the form of a first set of global user requirements. It has been used in eight case studies. The results of these case studies have led to improvements to the method and suggestions for further research.

Date of Conference: 16-19 Oct. 2008 Conference name: 2008 IEEE Workshop on Machine Learning for Signal Processing One common problem in signal denoising is that if the signal has a blocky, in other words a piecewise-smooth structure, the denoised signal may suffer from oversmoothed discontinuities or exhibit artifacts very similar to Gibbs phenomenon. In the literature, total variation methods and some modifications on the signal reconstructions based on wavelet coefficients are proposed to overcome these problems. We take a novel approach by introducing principal curve projections as an artifact-free signal denoising filter alternative. The proposed approach leads to a nonparametric denoising algorithm that does not lead to Gibbs effect or so-called staircase type unnatural artifacts in the denoised signal. ©2008 IEEE.

Date of Conference: 22-24 October, 2007 Conference name: International Workshop on Engineering Societies in the Agents World. ESAW 2007: Engineering Societies in the Agents World VIII As the web services proliferate and complicate it is becoming an overwhelming job to manually prepare the web service compositions which describe the communication and integration between web services. This paper analyzes the usage of the Event Calculus, which is one of the logical action-effect definition languages, for the automated preparation and execution of web service compositions. In this context, abductive planning capabilities of the Event Calculus are utilized. It is shown that composite process definitions in OWL-S can be translated into Event Calculus axioms so that planning with generic process definitions is possible within this framework. © 2008 Springer-Verlag Berlin Heidelberg.

Date of Conference: 6-11 July 2008 Conference name: 2008 IEEE International Symposium on Information Theory A method is proposed, called channel polarization, to construct code sequences that achieve the symmetric capacity I(W) of any given binary-input discrete memoryless channel (B-DMC) W. The symmetric capacity I(W) is the highest rate achievable subject to using the input letters of the channel equiprobably and equals the capacity C(W) if the channel has certain symmetry properties. Channel polarization refers to the fact that it is possible to synthesize, out of N independent copies of a given B-DMC W, a different set of N binary-input channels such that the capacities of the latter set, except for a negligible fraction of them, are either near 1 or near 0. This second set of N channels are well-conditioned for channel coding: one need only send data at full rate through channels with capacity near 1 and at 0 rate through the others. The main coding theorem about polar coding states that, given any B-DMC W with I(W) > 0 and any fixed 0 < δ < I(W), there exist finite constants n1 (W, δ) and c(W, δ) such that for all n ≥ n1, there exist polar codes with block length N = 2n, rate R > I(W)-δ, and probability of block decoding error Pe ≤ cN-1/4. The codes with this performance can be encoded and decoded within complexity O(N log N). © 2008 IEEE.

This paper derives robust niiniinax estimators for a class of uncertain models. The uncertainty is described by a relative entropy constraint between the unknown joint distribution and a fixed nominal joint distribution. The maximization is addressed using variational methods, while the minimization is addressed using the concept of a sufficient statistic, which is an unnormalized version of the a posteriori density. The theory developed is applied to multipath fading wireless channels, to derive minimax envelope and phase estimates. Related results are also derived when the uncertainty shrinks to zero. © 2008 IEEE. 1238 1242

In this paper we present FailRank, a novel framework for integrating and ranking information sources that characterize failures in a grid system. After the failing sites have been ranked, these can be eliminated from the job scheduling resource pool yielding in that way a more predictable, dependable and adaptive infrastructure. We also present the tools we developed towards evaluating the FailRank framework. In particular, we present the FailBase Repository which is a 38GB corpus of state information that characterizes the EGEE Grid for one month in 2007. Such a corpus paves the way for the community to systematically uncover new, previously unknown patterns and rules between the multitudes of parameters that can contribute to failures in a Grid environment. Additionally, we present an experimental evaluation study of the FailRank system over 30 days which shows that our framework identifies failures in 93% of the cases. We believe that our work constitutes another important step towards realizing adaptive Grid computing systems. © 2008 IEEE. 291 298 Conference code: 73523 Cited By :2

Most of the fault identification problems in the Discrete Event Systems literature assume knowledge of the structure of the net system, including the nature (and behavior) of the possible faults. In this paper we deal with this problem within the framework of Petri nets by removing the requirement that the nature (and behavior) of the fault is known. In particular, we devise a way to identify the structure of the faulty transitions of the system given its language. Then, we generalize this procedure to unobservable faults, in which case the structure of the faulty system needs to be recognized from the knowledge of the structure of the fault-free system, and the projection of the faulty system language on the set of non-faulty events, that are assumed to be observable. ©2008 IEEE. 455 461

In this work, using a game-theoretic approach, cost-sensitive mechanisms that lead to reliable Internet-based computing are designed. In particular, we consider Internet-based master-worker computations, where a master processor assigns, across the Internet, a computational task to a set of potentially untrusted worker processors and collects their responses. Several game-theoretic models that capture the nature of the problem are analyzed and mechanisms that, for each given set of cost and system parameters, achieve high reliability are designed. Additionally, two specific realistic system scenarios are studied. These scenarios are a system of volunteering computing like SETI, and a company that buys computing cycles from Internet computers and sells them to its customers in the form of a task-computation service. Notably, under certain conditions, non redundant allocation yields the best trade-off between cost and reliability. © 2008 IEEE. 315 324 Sponsors: IEEE Comput. Soc. Technical Committee on Distributed Processing Akamai Technologies, Inc. International Research Institute on Autonomic Network Computing Conference code: 73523 Cited By :11

A test bed has been developed in which participants are tasked to work in simulated, scenario based, projects in which face-to-face and remote meetings of about 45 minutes have to be held. Measures on performance, team factors and remote aspects are automatically collected with electronic questionnaires. The sensitivity and reliability of these questionnaires are positively evaluated. The test bed is now ready to be used for evaluating how well meeting assistants support collocated meetings and videoconferencing. © 2008 Springer-Verlag Berlin Heidelberg.

A test bed has been developed in which participants are tasked to work in simulated, scenario based, projects in which face-to-face and remote meetings of about 45 minutes have to be held. Measures on performance, team factors and remote aspects are automatically collected with electronic questionnaires. The sensitivity and reliability of these questionnaires are positively evaluated. The test bed is now ready to be used for evaluating how well meeting assistants support collocated meetings and videoconferencing. © 2008 Springer-Verlag Berlin Heidelberg.

Self-organisation (self-optimisation, self-configuration, and self-healing) methods are a promising concept to automate wireless access network planning, deployment and optimisation. This paper contains a mind setting exercise. First the mechanisms for which self-organisation is anticipated to be effective and feasible are identified. Then technical and non-technical requirements that need to be taken into account for the successful development of self-organisation functionalities are discussed. Furthermore, a set of metrics and appropriate reference cases (benchmarks) are presented, which allow to do on one hand a quantitative comparison of the different algorithms developed for a given use case, and on the other hand to evaluate the gains from self-organisation by comparing self-organisation solutions with the case of manual network operations. © 2008 Springer Berlin Heidelberg.

Laughter is a highly variable signal, which can be caused by a spectrum of emotions. This makes the automatic detection of laughter a challenging, but interesting task. We perform automatic laughter detection using audio-visual data from the AMI Meeting Corpus. Audio-visual laughter detection is performed by fusing the results of separate audio and video classifiers on the decision level. This results in laughter detection with a significantly higher AUC-ROC than single-modality classification. © 2008 Springer-Verlag Berlin Heidelberg.

Motivated by security applications where the initial state of a system needs to be kept secret (opaque) to outside observers (intruders), we formulate, analyze and verify the notion of initial-state opacity in discrete event systems. Specifically, a system is initial-state opaque if the membership of its true initial state to a set of secret states remains opaque to an intruder who is modeled as an observer of the system activity through some projection map. In other words, based on observations through this map, the observer is never certain that the initial state of the system is within the set of secret states. To verify initial-state opacity, we address the initial-state estimation problem in discrete event systems via the construction of an initial-state estimator. This estimator captures estimates of the initial state of the system which are consistent with all observations obtained so far. We also analyze the properties and complexity of the initial-state estimator. ©2008 IEEE. 328 333

This paper introduces a formal method to aggregate over basic beliefs, in order to deduce aggregated or complex beliefs as often used in applications. Complex beliefs can represent several things, such as a belief about a period in which other beliefs held or the minimal or maximal certainty with which a belief held. As such they contain richer information than the basic beliefs they are aggregated from and can be used to optimize an agent's search through its memory and its reasoning processes. The developed method can also aggregate over aggregated beliefs, hence nested aggregations are possible. An implementation in Prolog demonstrates its operationality. © 2008 Springer-Verlag Berlin Heidelberg.

Realistic simulation of virtual characters is essential in many applications and particularly in computer games. Having a realistic simulation of an agent is a complex matter since there are many different ways in which the real equivalent would have responded in real life. In addition a human viewer is very accustomed to observing other humans so the slightest inconsistency will be picked up. The complexity of the task increases when we address the simulation of groups of virtual agents interacting amongst them. In this paper we argue that, given the current state of the art, example based methods provide a lot of promise in addressing the realistic simulation. We start by discussing the recently proposed example based methods and then continue to present a novel approach based on texture synthesis. Although it is still work in progress, some preliminary results indicate that this is a viable approach that could potentially achieve results not so easily reached with rule based methods. © 2008 Springer Berlin Heidelberg. 5277 LNCS 1 10 Sponsors: GATE project NLGD Festival of Games Conference code: 74866 Cited By :3

Self-organisation (self-optimisation, self-configuration, and self-healing) methods are a promising concept to automate wireless access network planning, deployment and optimisation. This paper contains a mind setting exercise. First the mechanisms for which self-organisation is anticipated to be effective and feasible are identified. Then technical and non-technical requirements that need to be taken into account for the successful development of self-organisation functionalities are discussed. Furthermore, a set of metrics and appropriate reference cases (benchmarks) are presented, which allow to do on one hand a quantitative comparison of the different algorithms developed for a given use case, and on the other hand to evaluate the gains from self-organisation by comparing self-organisation solutions with the case of manual network operations. © 2008 Springer Berlin Heidelberg.

Models and specifications can be used in the design of distributed applications to formally reason about their safety properties. However, the benefits of using formal methods are often negated by the ad hoc process of mapping the semantics of an abstract specification to algorithms designed to be executed on target distributed platforms. The challenge of formally specifying communication channels and correctly implementing them as algorithms that use realistic distributed system services is the focus of this paper. This work provides an original formal specification of an abstract asynchronous communication channel with support for dynamic creation and tear down of links between participating network nodes, and its implementation as an algorithm using Java sockets. The specification and the algorithm are expressed using the Input/Output Automata formalism, and it is proved that the algorithm correctly implements the specification, viz. that any externally observable behavior (trace) of the algorithm has a corresponding behavior of the specification. The approach presented here can be used to implement algorithms for dynamic systems, where communicating nodes may join, leave, and experience delays. The result is also of direct benefit to automated code generation, such as that implemented within the Input/Output Automata Toolkit at MIT. © 2008 IEEE. 211 219 Sponsors: IEEE Comput. Soc. Technical Committee on Distributed Processing Akamai Technologies, Inc. International Research Institute on Autonomic Network Computing Conference code: 73523 Cited By :2

We developed acoustic and lexical classifiers, based on a boosting algorithm, to assess the separability on arousal and valence dimensions in spontaneous emotional speech. The spontaneous emotional speech data was acquired by inviting subjects to play a first-person shooter video game. Our acoustic classifiers performed significantly better than the lexical classifiers on the arousal dimension. On the valence dimension, our lexical classifiers usually outperformed the acoustic classifiers. Finally, fusion between acoustic and lexical features on feature level did not always significantly improve classification performance. © 2008 Springer-Verlag Berlin Heidelberg.

The compound capacity of uncertain MIMO channels is considered, when the channel is modeled by a class described by an induced norm constraint. Within this framework, two types of classes are investigated, namely, additive and multiplicative uncertainties subject to a spectral norm constraint, using partial channel state information at the transmitter side. The compound capacity is defined as a maxmin of the mutual information, corresponding to the capacity of the class, in which the minimization is done over the class of channels while the maximization is done over the transmit covariance. Closed form solutions for the compound capacity of the classes are obtained while several properties related to transmit and received eigenvectors are presented. It is also shown that capacity of the class of channels is equal to the worst-case channel capacity, while establishing a saddle-point property. Additionally, explicit closed-from solutions are given for the capacity-achieving Tx covariance matrix and the worst-case channel uncertainty. The effect of uncertainty is shown to be equivalent to an SNR loss which is proportional to the size of the uncertainty of the channel matrix measured by the spectral norm. © 2008 IEEE. 2578 2582