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In this paper, we present an approach for adaptive replication to support fault tolerance. This approach uses a feedback control theory methodology within an adaptive replication infrastructure to determine replication degrees of replica groups. We implemented this approach in a multi-agent system to survive Byzantine failures. At the end of the paper, we also provide some experimental results to show the effectiveness of our approach. [ABSTRACT FROM AUTHOR]

Some systems discard messages that wait in the queue longer than a certain threshold. Identifying such messages and discarding them takes the processor a fixed amount of time. That time is considerably smaller than an average service time, but greater than zero, therefore the models for queuing systems with reneging do not apply. This paper provides a model for such queues. It describes a method of deriving exact formulas for the distribution of waiting times, and proposes simple, yet accurate approximations. The paper then analyzes the model and discusses the properties of such systems. [ABSTRACT FROM AUTHOR]

Under the assumption that packets are sufficiently interleaved and the sampling rate is small, we show in this paper that those characteristics of flows like the number of packets, volume, etc. obtained through deterministic 1-out-of-k packet sampling is equivalent to random packet sampling with rate p = 1/k. In particular, under mild assumptions, the tail distribution of the total number of packets in a given flow can be estimated from the distribution of the number of sampled packets. Explicit theoretical bounds are then derived by using technical tools relying on bounds of Poisson approximation (Le Cam's Inequality) and refinements of the central limit theorem (Berry-Essen bounds). Experimental results from an ADSL traffic trace show good agreement with the theoretical results established in this paper. [ABSTRACT FROM AUTHOR]

Network traffic measurements can provide essential data for network research and operation. While Internet traffic has been heavily studied for several years, there are new characteristics of traffic having not been understood well brought by new applications for example P2P. It is difficult to get these traffic metrics due to the difficulty to measurement traffic on line for high speed link and to identify new applications using dynamic ports. In this paper, we present a broad overview of Internet traffic of an operated OC-48 export link of a metro area network from a carrier with the method of measurement on-line. The traffic behaves a daily characteristic well and the traffic data of whole day from data link layer to application layer is presented. We find the characteristics of traffic have changed greatly from previous measurements. Also, we explain the reasons bringing out these changes. Our goal is to provide the first hand of traffic data that is helpful for people to understand the change of traffic with new applications. [ABSTRACT FROM AUTHOR]

For a broad class of polling models the evolution of the system at specific embedded polling instants is known to constitute a multi-type branching process (MTBP) with immigration. In this paper it is shown that for this class of polling models the vector ${\underline{X}}$ that describes the state of the system at these polling instants satisfies the following heavy-traffic behavior, under mild assumptions: 1$$ \label{eq01} (1-\rho){\underline {X}} \rightarrow_d {\underline {\gamma}}~\Gamma(\alpha, \mu)~~~~(\rho \uparrow 1), $$ where ${\underline {\gamma}}$ is a known vector, Γ(α, μ) has a gamma-distribution with known parameters α and μ, and where ρ is the load of the system. This general and powerful result is shown to lead to exact - and in many cases even closed-form - expressions for the Laplace-Stieltjes Transform (LST) of the complete asymptotic queue-length and waiting-time distributions for a broad class of branching-type polling models that includes many well-studied polling models policies as special cases. The results generalize and unify many known results on the waiting times in polling systems in heavy traffic, and moreover, lead to new exact results for classical polling models that have not been observed before. As an illustration of the usefulness of the results, we derive new closed-form expressions for the LST of the waiting-time distributions for models with a cyclic globally-gated polling regime. As a by-product, our results lead to a number of asymptotic insensitivity properties, providing new fundamental insights in the behavior of polling models. [ABSTRACT FROM AUTHOR]

In this paper we investigate the maximum message throughput of the ActiveMQ server in different application scenarios. We use this throughput as a performance criterion. It depends heavily on the installed filters and the message replication grade. In previous work, we have presented measurement results and an analytical model for simple filters. This work extends these studies towards more complex configuration options. It provides measurement results and analytical performance models for complex AND-, OR-, and IN-filters. The results are useful to understand the performance of JMS servers and help to dimension large distributed JMS-based systems. [ABSTRACT FROM AUTHOR]

This paper presents the results of a simulation study that assessed SIP based VOIP networks under overload. This work addresses the issue of network level congestion controls in SIP based telephony networks. The simulation network consists of Media Gateways and Call Controllers, each with internal overload detection and control mechanisms. The simulation includes SIP timers tuned to operate gracefully with PSTN interfacing protocols. The traffic model is SIP based VoIP calls not involving application server or media server interactions. This work demonstrates that combining external overload controls with internal overload controls reduces blocking and increases goodput across the overload levels that ranged from 1 to 4 times the engineered load. [ABSTRACT FROM AUTHOR]

The Multimedia Modeling Language (MML) is a platform-independent modeling language for model-driven development of interactive multimedia applications. Using models provides several advantages like well-structured applications and better coordination of the different developer groups involved in the development process. However, the creative tasks - like graphical design of the user interface and the design of media objects - are better supported by traditional informal methods and tools. In particular multimedia authoring tools such as Adobe Flash are well established for multimedia application development. In this paper we show how MML and authoring tools can be integrated by the example of Flash. Therefore we transform the MML models into code skeletons which can be directly loaded into the Flash authoring tool to perform the creative design tasks and finalize the application. In that way, the strengths of models and authoring tools are combined. The paper shows the required level of abstraction for the models, introduces a metamodel and a suitable code structure for the Flash platform, and finally presents the transformation. [ABSTRACT FROM AUTHOR]

The role of interface design is to enable communication between people and the technical product such as a cellular phone, computer, or PDA. To use the product successfully, the interface design should be easy to use. The objective of this paper is to create a practical and user-friendly interface design for a wireless device to control home appliances. In order to control home appliances with a cellular phone, the author suggests a natural (intuitive) interface design that is friendly and attractive to users, based on their experience, and effectively uses graphic elements such as layout, icon, color, and text. As part of this natural (intuitive) interface design, the author suggests using a wheel key to control a cursor system for navigating a cellular phone screen. A usability test was conducted to determine problems people have while using the prototype. The results of the usability test indicated that the user interface was successful, and participants were satisfied with the prototype. [ABSTRACT FROM AUTHOR]

We analyze and discuss human performance model for PBUI (Push-Based User Interface) in this paper. PBUI is a user interface method in which a user performs a desired task by selecting a target object that usually represents the task itself. The candidate objects are sequentially and automatically presented to the user by the system. When a target object is presented, user selects the target object by a simple action such as just pushing a button. In this paper, we propose human performance model of PBUI and discuss the characteristics of PBUI. We also evaluate performance of PBUI by comparing with GUI. [ABSTRACT FROM AUTHOR]

Early evaluation of interactive systems is currently the subject of numerous researches. Some of them aim at explicitly coupling design and evaluation by various software mechanisms. We describe in this paper two approaches of early evaluation exploiting new technologies and paradigms. The first approach is based on aspect oriented programming; the second one proposes an explicit coupling between agent-oriented architecture and evaluation agents. These two approaches are globally compared in this paper. [ABSTRACT FROM AUTHOR]

This paper reports the findings of an evaluation of an adaptive multimodal application for reading of rich digital talking books. Results are in accordance with previous studies, indicating no user perceived difference between applications with and without adaptivity. The NASA Task Load Index was also used and showed that users of the adaptive application reported less workload. Results also include a comparison between tasks executed with electronic support and tasks executed with print support, and also what specific features in the interface benefited the most from the use of visual and audio modalities. [ABSTRACT FROM AUTHOR]

This paper presents a tool that supports a scenario based expert evaluation method called DEPTH (usability evaluation method based on DEsign PaTterns & Heuristics criteria). DEPTH is a method for performing scenario-based heuristic usability evaluation of e-systems. DEPTH focuses on the functionality of e-systems and emphasizes on usability characteristics within their context. This can be done not only by examining not only the availability of a functionality within an e-system but also the usability performance of the supported functionality according to a specific context of use. The main underlying ideas of DEPTH are: i) to minimize the preparatory phase of a usability evaluation process and ii) to assist a novice usability expert (one who is not necessarily familiar with the genre of the e-system). Thus, we (re)use expert's knowledge captured in design patterns and structured as design pattern languages for the various genres of e-systems. This paper briefly describes the DEPTH method and presents the way a specially designed tool supports it along with the findings from an evaluation study. [ABSTRACT FROM AUTHOR]

This paper proposes a simple framework for implementing SBD. This framework consists of four elements: a basic story structure, an innovation acceleration field, a tool for expressing idea/describing scenario, and an activity theory-based tension detector/idea stimulator, and a process based on the Chinese traditional literature four-stage creation process. A case study is presented at the end of the paper to demonstrate the feasibility of the proposed framework. [ABSTRACT FROM AUTHOR]

This paper describes the development and piloting of a user-centered design method which enables participants to actively engage in a creative process to produce intuitive representations and inspire early design concepts for innovative mobile and ubiquitous applications. The research has been produced as part of the EC funded project PASION, aiming to enhance mediated communication in games and collaborative environments through the introduction of socio-emotional information cues, represented in meaningful yet abstract enough ways to accommodate variable thresholds of privacy. We describe our design research methodology, which combines analytical approaches, aiming to uncover participant's needs, desires and perceptions with creative, generative methods, with which participants inform and inspire the design process. [ABSTRACT FROM AUTHOR]

This paper presents two case studies of prototype evaluation as a tool for user needs elicitation for emerging technologies. In the first user evaluation, a high-fidelity virtual reality prototype is used. In the second one, a low-fidelity mixed reality prototype is used. Our results show that prototypes may be a powerful a tool for eliciting user-needs, but their potentiality depends on their fidelity. In our studies, users elicit more needs when working with the high-fidelity prototypes. Furthermore, the information collected in this case is richer and more useful for design. We discuss these results as well as some factors that could help stakeholders elicit a greater number of needs for emerging technologies. [ABSTRACT FROM AUTHOR]

Since the 1980s User-Centered Design (UCD) has been becoming popular in the ICT industry. It helps seek usable designs through a set of workflows, evaluation methods, and design approaches, which construct a comprehensive UCD framework. Along with its extensive utilizations, its pitfalls are also exposed in cost-benefit, robustness, and optimization respects. However, applying the Taguchi Method can remedy these pitfalls to gain robust optimal designs. This approach is feasible but less emphasized in the Human-Computer Interaction field. From a theoretical perspective, this paper depicts a practical approach to enhance UCD framework by adopting the Taguchi philosophy. Based on the analysis of the UCD framework and the Taguchi Method, it discusses key adaptation points for the Taguchi philosophy adoption in the UCD framework. As a result, the Taguchi-Compliant User-Centered Design (TC-UCD) framework is proposed in this paper. [ABSTRACT FROM AUTHOR]

The narration board is a powerful design tool to help translate user observation studies into a storytelling format. It helps to communicate design values and ideas among the design team via visualising user scenarios in its proper context during the early design stages. This paper aims to discuss the narration board as a design tool to help the design team conceptualise and visualise user scenarios interacting with future design concepts within its context of use. Second part of the paper discusses how narration boards assist in generating ideations and visualising final design concepts by interface designers. Twenty (20) design projects (N=20) were examined to study and quantify two important factors, i.e. the components of the narration board in relation with the attributes of the final design concepts. A non-parametric correlation test was used to study the correlation coefficient between scores of the two factors. The results show that there is a statistically significant positive correlation between components of the narration board and attributes of the final design concept. Those with higher scores of components in narration board tend to produce better final design concepts, and vice versa. [ABSTRACT FROM AUTHOR]

Designing for Chinese industries and the new China market has became a ‘hot‘ issue within the global and Chinese industrial design society. The characteristics of low labor costs and hard-working Chinese have had an effect on the rapid economic development within the region as a whole. The purpose of this paper is to analyze state of the art industrial development within Taiwan and Mainland China, and to evaluate the critical problems of industrial design development in both regions. Additionally to discover how Taiwan Chinese digital technology industries confront this situation with user-oriented design (UOD). This paper synthesizes six approaches to carry out an innovative product development framework of new product development procedures, with user oriented scenario predictions and experience innovation approach. These approaches not only generate original design data from a user's point of view, but furthermore make it much easier to get consensus from product development teams and really create innovative designs through interdisciplinary collaboration to create innovative cultural enterprises. [ABSTRACT FROM AUTHOR]

This paper focuses on the time period between September 2005 and September 2006 where HCI research experiments were deployed in a post-hurricane Katrina disaster area. This area stretched from the cities of Waveland and Bay St. Louis, Mississippi (the epicenter of hurricane Katrina) to shelters in Baton Rouge and Houston, Texas. The HCI experiments were constructed in order to understand immediate disaster aftermath issues of a population in context of activities, information and organizational needs. The use of a Participatory Design (PD) methodology, Ethnographic techniques, and design Probes were refined over the course of the longitudinal study. Field notes were created in an iterative process with individual participants over a course of time due to the impact of shock and cognitive issues early on. These field notes then influenced a set of personas that were iterated and used as a vehicle to gather and validate field research findings and people's needs within the disaster framework. The main goal of this paper is not to propose informational, organizational or technology solutions to the complex problems inherent in a disaster cycle, but to illustrate both the failure and success of using HCI methods in a post disaster situation. Therefore, a disaster cycle is outlined and described in this paper. Insights and thoughts regarding the Rescue and Recovery phases are described and notes where HCI as a practice may influence or contribute to these areas within the disaster cycle are outlined. The last part of the paper illustrates the first HCI experiment in the field and some of the iterations and findings from this practice. This first research study was undertaken at a grassroots level, yet this does not mean valuable information could not be gathered in further studies of governmental, NGOs, or businesses participating in planning, preparing or rescue and recovery efforts during a disaster. In fact, the opportunity to combine grassroots and governmental HCI research could offer immense benefits. However, as a grassroots initiative it is a level of inquiry without the constraints of political hierarchy. Given this, this paper focuses less on how HCI can be used in a more typical framework where a sponsor, such as a client and HCI worker are collaborating in HCI "workplace" research, and more on developing tools and methods within communities. [ABSTRACT FROM AUTHOR]

Engineering changes, whether it is desirable or undesirable, incur cost and delay in schedule. It should be avoided as much as possible and change management strategy should be chosen as to minimize the overall cost. This paper proposes a method to represent change propagation and formulate change absorbing problem into mathematical programming. Solution to the mathematical problem can lead to optimal change absorbing strategy that minimizes overall cost. [ABSTRACT FROM AUTHOR]

Brainstorming is a commonly used method for diffusion thinking in early design stage. While the communication between two participants is blocked with isolated communication boundaries, the ideas are often transferred via a propagated interaction process among design team participants. The paper describes an organization-communication method to study the interaction between designers and design teams using act/react characteristics of role-interplay. Adapting a role-play framework called DARIS; a particular controlling agent called Playwright Agent is developed and used for implementing the adaptive scripts. Furthermore, by simulating the interconnecting process among discrete communication boundaries, the interaction and controlling mechanism of Playwright Agent is also unleashed in the paper. The mechanism and the agent implementation of proposed framework, namely DARIS +  is shown to represent the interaction as well as their consequence. An example for describing how Playwright Agent works is also shown in the paper. [ABSTRACT FROM AUTHOR]

This paper presents several experiments carried out by the AmILAB research group of Tekniker in the framework of the WearIT@work project (EC IP 004216) on the use of wearable technology base solutions for the training process of workers in a manufacturing environment. The description includes both the initial work at the SKODA production facilities in Czech Republic and the experiments with local workers at Tekniker. As an introduction, the authors of this paper shortly describe current training processes at Skoda, and derive the potential benefits and risks of applying wearable computing technology. [ABSTRACT FROM AUTHOR]

We describe a role-based multiple view approach to support sharing and coordination of knowledge in geo-collaborative planning. The software coordinates multiple unshared role-specific views with one shared team view. The rationale for this approach is that: (1) it affords clear separation between role-specific and shared knowledge; (2) it leverages experts' knowledge to filter out role-specific details; and (3) it promotes implicit sharing of strategic knowledge (i.e. about roles). We illustrate the key features implemented in a prototype to evaluate this approach, describe design requirements extracted from a paper prototype study, and discuss relevant design issues. [ABSTRACT FROM AUTHOR]

This paper presents a couple of tool-sets that allows the management of group therapy sessions, for a single room with a large public display setting. These sessions involve several patients, a main therapist and eventually a second therapist. Information is created, exchanged and discussed between them during those sessions. All participants recur to different devices to perform their activities, from PDAs to PCs, through an interactive large display, if available. Devices are selected and tool-sets designed adequately for each setting and participant role. For the main therapist, the variant with an interactive large display, required the simultaneous usage of a complimentary devices, to cope with non-public aspects of the therapy. Preliminary evaluation rose interesting, one hand usage issues for that variant. [ABSTRACT FROM AUTHOR]

The mismatch between ‘traditional‘ educational model and the e-Learning has drawn the research attention on personalized instruction, one of the growing concerns in HCI. This paper presents a framework that can be used as a basis for the identification of an appropriate type of personalization. Our idea is that users who demonstrate particular learning styles, as identified in Felder-Silverman's learning style theory, require a specific e-learning environment that matches their learning preferences. In particular, the framework is formulated to investigate how the different modalities presenting e-Learning content will influence the students' learning quality and experience. The considered learning styles profile in this paper is typical for a science and technology domain student. Through this framework we expect that learning preferences of a certain type of learners could be better supported and consequently their improved learning performance. [ABSTRACT FROM AUTHOR]

This paper describes a multi-platform framework that supports a set of activities performed by both teachers and students within an educational context. The framework's main contribution lies on the possibility given to teachers to customize, according to various dimensions (e.g., content, user context, and subject), material that is later provided to students. On the other hand, students are allowed to accomplish their activities ubiquitously through mobile devices (e.g. PDAs). The second contribution however, is the ability that teachers gain to detect learning difficulties and problems faced by students while accomplishing their tasks even while away from classes and school. We describe the experiences that have been conducted and present some results that address both educational and human-computer interaction issues. [ABSTRACT FROM AUTHOR]

This paper discusses a sensory evaluation technique to find relationships between advertisements on Auto teller Machine (ATM) screen and users' financial preferences under the extended AIDMA model which represents Attention, Interest, Desire, Memory and Action. The basic three financial preferences are purchasing, savings and investment. Twenty assessors performed three steps of; checked by Marble Method and Correspondence Analysis with Supplementary Treatment thorough trial experimentation of e-Commerce. This survey, using ATM advertisements, clarified users' dynamic financial preference shifts through the e-Commerce influence. In conclusion, the purchasing and the investment groups shift to the saving group. In this tendency it is surmised that looking at full varieties of the catalogues in the e-Commerce influenced the financial preferences. This experimentation can be applied to the environment of the customer relationship management (CRM). [ABSTRACT FROM AUTHOR]

Mobile and ubiquitous systems designed to promote an increase in physical activity by harnessing social influence have so far had variable success. Taking a cardiac rehabilitation program as a specific health domain, in which physical inactivity is one of several targeted behaviours, the research described in this paper aims to elicit understanding of peer-involvement in health-related behavioural change and explore the potential for effective technological support. This paper introduces the technology probe Collabohab and discusses the accompanying methodological approach being adopted to establish insight into the important but so far little understood phenomenon of social support within health-related behavioural change. [ABSTRACT FROM AUTHOR]

User-centered design is not just about building nice-looking and usable interfaces, and software development is not just about implementing functionality that supports user tasks. This paper aims to build a tighter fit between human-computer interaction and software engineering practices and research by addressing what software and usability engineering practitioners can learn from each other regarding the impact of usability on software development. More specifically we aim to support usability people in helping developers to elicit requirements that can incorporate usability functions into software development. The paper shows what type of impact usability has on software models and suggests how this impact can be dealt with at the requirements elicitation and specification stages of the development cycle. [ABSTRACT FROM AUTHOR]

With the emergence of pervasive technology, pervasive games came into existence. Most are location-aware applications, played with a PDA or mobile phone. We argue that the interaction paradigm these games support, limits outdoor play that often involves spontaneous social interaction. This paper introduces a new genre of pervasive games we call Head Up Games. The paper describes these games and how they differ from current research prototypes of pervasive games. Also, it outlines their characteristics and illustrates our vision with Camelot, an outdoor game for children. [ABSTRACT FROM AUTHOR]

This paper introduces a novel kinesthetic interaction technique for interactive floors. The interaction techniques utilize vision-based limb tracking on an interactive floor - a 12 m2 glass surface with bottom projection. The kinesthetic interaction technique has been developed for an interactive floor implemented in a school square. The paper discusses the kinesthetic interaction technique and its potentials in the domain of learning applications: Kinesthetic interaction supports body-kinesthetic learning as argued in the learning literature. Kinesthetic interaction is fun and motivating thus encourages children to explore and learn. Kinesthetic interaction on large display surfaces supports collaborative, co-located play and learning through communication and negotiation among the participants. Finally, the paper discusses prospects and challenges in development of kinesthetic interaction for interactive floors. [ABSTRACT FROM AUTHOR]

Studies in video mediated collaboration are going beyond traditional measures of time on task and task accuracy by attempting to qualify specific aspect of users' experience. This paper explores users' sense of co-presence as the extent to which they feel co-present with their partner when building collaboratively a toy over a video conferencing system. A linguistic analysis of the way users are referring to remote objects and places has been conducted in order to investigate the correlation between co-presence score and the frequency of local and remote deixis. Our results indicate that co-presence score is positively correlated to the frequency of local deixis as reported previously [1] and negatively correlated to remote deixis. We conclude that the words used by users when referring to remote objects and places may indicate aspects of user's experience while engaged in remote collaboration. [ABSTRACT FROM AUTHOR]

This paper examines the use of surveys in measuring privacy concerns in ubiquitous computing environments. Two evaluation techniques are used to study the privacy concerns of sharing context information: a paper based survey and in-situ questionnaires. Results from the two techniques differ significantly, suggesting that surveys are not reliable in predicting privacy concerns regarding context-aware services. Further, the surveys are not consistently biased; for some information, people shared more in-situ than they predicted they would share in the survey, while for other types, they shared less. [ABSTRACT FROM AUTHOR]

This paper provides support for the use of motivational needs in identifying mobile phone uses and related features. Drawing on motivational human and usage space research, the findings of interviews and surveys, this paper proposes the Mobile phone Usage Space Model (MUSM). MUSM distinguishes between two groups of features by identifying necessary and additional features, thus focusing the designer's activity on motivational needs-driven design, rather than feature escalation that currently appears to dominate. [ABSTRACT FROM AUTHOR]

The beautification of a user interface resulting from model-to-model and model-to-code transformations in Model-Driven Architecture consists of performing manual changes to address user requirements which have not been supported during the transformations. These requirements may include customization, users' preferences, and compliance with corporate style guidelines. This paper introduces a beautification process into a user-interface model. This process includes a series of beautification operations based on a formal definition, as well as a constrained editor that enables designers to apply these beautification operations on a user interface. All manual changes done using these beautification operations are transformed into model-to-model transformations, thus reducing the problem of round-trip engineering. The paper also demonstrates that this process significantly reduces the number of manual changes performed on user interfaces of information systems, while preserving the quality properties induced by the transformations. [ABSTRACT FROM AUTHOR]

This paper analyzes the problem of evaluating elderly people's perception of assistive robots and domotic environments. Specifically, we focus on aspects related to the modalities in which interaction can occur between an elder user and an assistive robotic agent. Our work benefits from the products of project RoboCare, namely, a domestic environment in which sensors, intelligent software components and a domestic robot provide a set of cognitive support services for the elder user. This paper analyzes a number of evaluation criteria in detail, specifically related to the robot's aspect, the way in which it communicates with the user, and the perceived usefulness of its support services. Among these criteria, the paper proposes and reports an evaluation of the Proactive interaction modality (where the system takes the initiative) and On-demand interaction (in which the user explicitly requests a service). Users evaluate the On-demand support services in personal safety scenarios as particularly useful, and less so in scenarios which are not critical. The paper also provides a discussion which can be useful for the design of future assistive agents and robotic companions. [ABSTRACT FROM AUTHOR]

In this paper we present a new algorithm for automatic recognition of hand drawn sketches based on the Levenshtein distance. The purpose for drawing sketches in our application is to create graphical user interfaces in a similar manner as the well established paper sketching. The new algorithm is trainable by every user and improves the recognition performance of the techniques which were used before for widget recognition. In addition, this algorithm ay serve for recognizing other types of sketches, such as letters, figures, and commands. In this way, there is no modality disruption at sketching time. [ABSTRACT FROM AUTHOR]

This paper describes a novel browsing paradigm, taking benefit of the various types of links (e.g. thematic, temporal, references, etc.) that can be automatically built between multimedia documents. This browsing paradigm can help eliciting multimedia archives' hidden structures or expanding search results to related media. The paper intend to present a novel model for browsing any kind of multimedia archives and further focuses on an archive of meetings recordings, in order to illustrate the advantage of our method to perform cross-meetings and in general cross-documents browsing. First of all, the structure of meeting datasets is presented, describing in particular the media implied, the annotations used for cross-document linking and the major mining techniques integrated in this work. Then, the paper presents at a glance the visual browser we developed that combines searching and browsing by links. Further, the performances of the actual system are discussed, i.e. the automatic indexing and linking processes for the two different meeting corpora, as well as the access and browsing performances. Finally, the paper presents the major unsolved issues and our perspectives for future works. [ABSTRACT FROM AUTHOR]

This paper presents Manas, a Semiotic Engineering epistemic tool for the design of collaborative systems (CoSys) whose aim is to expand the designers' knowledge and awareness of their influence on groups and group dynamics. Manas has been developed to help designers represent their conception of computer-mediated communication and reflect upon some of its potential social effects, springing from user-system interaction, as well from user-user interaction (through the system). The paper illustrates how Manas can lead designers to reflect upon both the design problem and its proposed solution(s), which allows them to make more conscious decisions. Increased knowledge and awareness should then enhance the quality of CoSys design. [ABSTRACT FROM AUTHOR]

Currently, grouping in XQuery must be expressed implicitly with nested FLWOR expressions. With XQuery 1.1, an explicit group by clause will be part of this query language. As users integrate this new construct into their applications, it becomes important to have efficient evaluation techniques available to process even complex grouping conditions. Among them, the removal of distinct values or distinct nodes in the partitions defined by the group by clause is not well-supported yet. The evaluation technique proposed in this paper is able to handle duplicate removal in the partitions efficiently. Experiments show the superiority of our solution compared to state-of-the-art query processing. [ABSTRACT FROM AUTHOR]

This paper uses Participatory Semantics to explicate commitment. Information expresses the fact that a system is in a certain configuration that is correlated to the configuration of another system. Any physical system may contain information about another physical system. For the purposes of this paper, physical commitment is defined to be information pledgedabout physical systems (situated at a particular place and time). This use of the term physical commitment is currently nonstandard. Note that commitment is defined for whole physical system; not just a participant or process. Organizational and social commitments can be analyzed in terms of physical commitments. For example systems that behave as scientific communities can have commitments for monotonicity, concurrency, commutativity, pluralism, skepticism, and provenance. Speech Act Theory has attempted to formalize the semantics of some kinds of expressions for commitments. Participatory Semantics for commitment can overcome some of the lack of expressiveness and generality in Speech Act Theory. [ABSTRACT FROM AUTHOR]

Hierarchical structures have been widely used by human organizations because they provide the natural means to delegate tasks, to reduce communication lines and to control the activities performed into them. This has motivated the development of different approaches to automate many of the activities that take place in hierarchical organizations. Recent frameworks, such as Gaia, Aalaadin, HarmonIA and OperA, among others, have considered the agent paradigm to do so without taking into account that organizations are dynamic entities that evolve with the time and, consequently, agents must adapt to changes. Here we develop a model for flexible and open hierarchical organizations where agents can dynamically adapt themselves to organizational changes. [ABSTRACT FROM AUTHOR]

The viability of the application of the e-Institution paradigm for obtaining overall desired behavior in open multiagent systems (MAS) lies in the possibility of bringing the norms of the institution to have an actual impact on the MAS. Institutional norms have to be implemented in the society. The paper addresses two possible views on implementing norms, the so-called regimentation of norms, and the enforcement of norms, with particular attention to this last one. Aim of the paper is to provide a theory for the understanding of the notion of enforcement and for the design of enforcement mechanisms in e-Institutions. [ABSTRACT FROM AUTHOR]

Support for new forms of organization and social interaction requires understanding the influence of structure on behavior. Goal dependencies indicate some relationship between roles, through which actions can be coordinated. Social relationships determine different types of power links between roles. Efficient coordination requires that goal dependency and power structure are well tuned to each other. In this paper, we will investigate what is the exact nature of this relationship between roles in an organization and what are the consequences of different structure forms. We will also see what is the difference if the relations are not hierarchical but organized through a market or network structure. [ABSTRACT FROM AUTHOR]

Artificial Intelligence has contributed (formal) design models and software support tools to application areas such as architecture, engineering and software design This paper explores the effectiveness of applying design models to the area of organization (re)design. To that purpose a component-based model for (re)design of organizations is presented as a specialization of an existing generic design model. Using recently developed formalizations within Organization Theory organization models are described as design object descriptions, and organization goals as design requirements. A design process specification is presented that models the redesign process for an organization that adapts to changes in the environment. The formally specified and implemented approach to organization redesign thus obtained has been tested for a well-known historical case study from the Organization Theory literature. [ABSTRACT FROM AUTHOR]

Recently Gerald Ash has shown through case studies that event dependent routing is attractive in large scale multi-service MPLS networks. In this paper, we consider the application of Load Shared Sequential Routing (LSSR) in MPLS networks where the load sharing factors are updated using reinforcement learning techniques. We present algorithms based on learning automata techniques for optimizing the load sharing factors both from the user equilibrium and system optimum perspectives. To overcome the computationally expensive gradient evaluation associated with the Kuhn-Tucker conditions of the system optimum problem, we derive a computationally efficient method employing shadow prices. The proposed method for calculating the user equilibrium solution represents a computationally efficient alternative to discrete event simulation. Numerical results are presented for the performance comparison of the LSSR model with the user equilibrium and the system optimum load sharing factors in some example network topologies and traffic demands. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of designing tractable dynamic admission control and/or routing policies in a Markovian model of parallel multi-server loss queues with reneging, which seek to optimize performance objectives of concern. Such problems are relevant in a variety of systems that provide distributed telecommunication or computing services. The paper shows the direct applicability of the author's results in Niño-Mora (2002) [Dynamic allocation indices for restless projects and queueing admission control: a polyhedral approach. Math. Program. 93 361-413], where index policies based on restless bandits were developed in a broader setting. A well-grounded and tractable index policy for admission control and/or routing is thus proposed for the model of concern. Results of preliminary computational experiments are reported, showing that the proposed index policy is nearly optimal, and substantially outperforms conventional benchmark policies in the instances investigated. [ABSTRACT FROM AUTHOR]

This paper focus on optimal Call Admission Control (CAC) policy for an IEEE 802.16 Wireless MAN. This policy has two objectives: (i) statistically guarantee the QoS of UGS, rtPS and nrtPS connections, (ii) maximize the average revenue of the wireless link. To find such optimal policy, we model our CAC agent as a Constrained Semi-Markov Decision Process (CSMDP). To the best of our knowledge, the only algorithm able to compute the optimal control policy of a CSMDP is based on the Linear Programming (L.P.) approach. Unfortunately, a realistic CAC problem with a large states space is intractable with the L.P. algorithm. Our work presents two contributions. First, the proposition of an optimal CAC for Triple-Play services support over a 802.16 WMAN. Second, the presentation of an alternative iterative algorithm that can be used to overcome the difficulties faced by the L.P. approach. [ABSTRACT FROM AUTHOR]

This paper describes the rationale behind a user interface requirements management notation and a supporting tool suite. The notation is being developed to facilitate the design of interactions based on an account of non-functional requirements (NFRs), thus the acronym NfRn for the technique. NfRn is a graphical notation which is used to specify an interactive system's global execution context (GEC). The resulting depiction is referred to as the Global Execution Context graph (GECg). The GECg is a visual construction, which consists of nodes, representing interaction scenarios, and directed links representing scenario relationships designating alternate execution, concurrency, ordering, and set-oriented relationships between two scenario nodes. The technique is particularly useful for specifying certain NFRs - such as adaptability, adaptivity, scalability and portability - which are especially relevant for anytime, anywhere access. In the paper, we demonstrate the application of the technique in the context of an on-going research project aiming to build an ‘electronic village' of local interest in the region of Crete. [ABSTRACT FROM AUTHOR]