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This paper deals with discrete time, single-input single-output systems. A parametrization of a general class of adaptive controllers is given. Using this paramtrization it is shown that an adaptive controller based on the l1 optimal design strategy leads to a globally convergent adaptive scheme. The use of adaptive l1 controllers is motivated by the problem of robust adaptive control, and the results of this paper offer an alternative way of handling this problem.

Recent advances in space applications have necessitated the deployment of robotic systems in space. These systems have intrinsic features due to the nonholonomic constraints governing their motion. In this paper we discuss the presence of nonholonomic redundancy, as different from ordinary kinematic redundancy, in space robots. Nonholonomic redundancy can be utilized to increase the workspace of space robots. In this paper we present a path planning scheme using Liapunov functions in hierarchy for the utilization of nonholonomic redundancy.

The timing behavior of a real-time system depends not only on delays due to process synchronization, but also on the availability of shared resources. Most current real-time models capture delays due to process synchronization; however, they abstract out resource-specific details by assuming idealistic operating environments. On the other hand, scheduling and resource allocation algorithms used for real-time systems ignore the effect of process synchronization except for simple precedence relations between processes. To bridge the gap between these two disciplines, we have developed a formalism called Communicating Shared Resources, or CSR. This paper presents the priority-based process algebra called the Calculus for Communicating Shared Resources (CCSR), which provides an equational characterization of the CSR language. The computation model of CCSR is resource-based in that multiple resources execute synchronously, while processes assigned to the same resource are interleaved according to their priorities. CCSR possesses a prioritized strong equivalence for terms based on strong bisimulation. The paper also describes a producer and consumer problem whose correct timing behavior depends on priority.

The paper defines an operator for superimposition, in contrast to previous transformational views. It does so in the context of the multiparty interaction as the primitive for synchronization and interprocess communication in distributed programs. The operator is given a (structured) operational semantics, and some aspects of its methodological importance are discussed. The papers distills the essentials of superimposition, in contrast to other approaches where its role is mixed with other programming aspects. A simple example of its use is provided. Large design examples and more details are presented elsewhere.

Going back to the beginning of the eighties, there has been numerous accounts of model-generated information systems being touted as the silver bullet to attack problems regarding software productivity and quality (Balzer, 1985). The CASE-tools of the late eighties were oversold on their ‘complete’ code-generation capabilities. Today similar arguments are found relative to the use of OMG’s Model-driven Architecture (MDA) approach (Thomas, 2004), using and integrating UML models on computational independent, platform independent, and platform specific models. Also a number of other areas, including enterprise modeling, workflow modeling, ontologies, and Service Oriented computing are proposed by their proponents as the direction to go to achieve model-generated solutions for tomorrows business applications. In the newly started EU IST Integrated Project ATHENA (Athena, 2004), we are investigating all of these approaches in parallel, specifically to address problems of business and system interoperability across organizational borders. This paper will outline the different approaches, and illustrating how they can be combined to support integrated and parallel enterprise and IS development, within and across enterprise boundaries, by supporting the development and evolution of appropriate models of high quality The rest of the paper is organized as follows. Section 2 overviews briefly the different modeling approaches. Section 3 gives an overview of the ATHENA project, whereas Section 4 presents aspects of how to integrate enterprise and IS development by combining these different model-driven approaches. This is not finalized in the project, thus the views on this that is expressed are those of the author, not of the Athena project. Section 5 concludes the paper and describes shortly work ahead on this approach.

We study distributed algorithms for networks with undetectable fail-stop failures, assuming that all of them had occurred before the execution started. (It was proved that distributed agreement cannot be reached when a node may fail during execution.) Failures of this type are encountered, for example, during a recovery from a crash in the network. We study the problems of leader election and spanning tree construction, that have been characterized as fundamental for this environment. We point out that in presence of faults just duplicating messages in an existing algorithm does not suffice to make it resilient; actually, this redundancy gives rise to synchronization problems and also might increase the message complexity. In this paper we investigate the problem of making existing spanning tree algorithms fault-resilient, and still overcome these difficulties. Several lower bounds and optimal fault-resilient algorithms are presented for the first time.However, we believe that the main contribution of the paper is twofold: First, in designing the algorithms we use tools that thus argued to be rather general (for example, we extend the notion of token algorithms to multiple-token algorithms). In fact we are able to use them on several different algorithms, for several different families of networks. Second, following the amortized computational complexity, we introduce amortized message complexity as a tool for analyzing the message complexity.

This paper presents a behavioral preorder for relating partial process specifications to implementations and establishes that it is “adequate” in the following sense: one specification may be used to characterize all implementations of a network component that are correct for any network context exhibiting a particular interface. This property makes the preorder particularly suitable for reasoning compositionally about networks of processes. The paper also gives a sound and complete axiomatization for finite processes of the largest precongruence contained in this new preorder.

This paper studies range equations and matrices with range entries. Range equations and their solutions are generalizations of compositions for consecutive sets of integers. Consistency and reducibility of range equations are due to data dependant semantics and the restrictions set by the query response strategy in statistical databases. Having determined the probability that a random solution to a given range equation is reducible, this paper relates it to the extent of security affordable in statistical databases and further generalizes it to matrices with range entries.

This paper treats a practical method to generate assembly strategies applicable to part-mating tasks that are of particular interest. The difficulties in devising reliable assembly strategies results from various forms of uncertainty such as an imperfect knowledge of the parts being assembled and limitations of the devices performing the assembly. Our approach to cope with this problem is to have the robot learn the appropriate control response to measured force vectors, that is, the mapping between sensing data and corrective motion of robot, during task execution. In this paper, the mapping is acquired by using a learning algorithm and represented with a binary tree type database. Remarkable features of the proposed method are the use of a priori knowledge and accomplishment of the task with little human trouble. Experiments are carried out by taking account of practical production facilities. It is shown by experimental results that an ideal mapping is acquired effectively by using the proposed method and the assembly task is carried out smoothly.

Computer systems with good human-computer interfaces and interaction are generally designed using user centred design techniques in which the design is realised through iterative cycles of ‘design, test with users, redesign’. Until formal methods replace or reduce the need for user testing prototyping and testing tools will play a central part in human-computer interaction (HCI) design. This paper reviews two established paradigms known as ‘usability engineering’ and ‘contextual evaluation’ (also called ‘contextual inquiry’). The advantages and disadvantages of each are highlighted and then criteria for an ‘ideal’ evaluation tool are proposed. The paper ends with a brief discussion of an evaluation tool which fulfils many of these criteria.

This paper considers the semantics of coroutines and processes in block structured languages; in particular, the problem of existence of static and dynamic environments. It is shown that a definition of inaccessible module instances may result in an inconsistent meaning of some operations. Both an Algol-like language and a SIMULA-like language, (with pointers yet without coroutines), are proven to have well-defined semantics. The examples provided in this paper show that some coroutine and concurrent operations may, however, destroy the static environment.

This paper presents an advanced control system we developed for an articulated gripper. This articulated gripper was previously designed to achieve stable grasp of objects with various shapes and to impart compliant fine motions to the grasped object. In the control system of this device we introduced autonomous reasoning capabilities. Fine motion strategies, needed for mating or grasping, use inductive learning from experiments to achieve uncertainty and error recovery (on sensing, control and model). An overview of the articulated gripper's capabilities is provided for a better understanding of the programming environment we propose. For solving the problem of synthesis programs for fine motion planning we introduce declarative programming facilities in the controller through a time-sensitive expert system. The paper gives some details on the implementation of this expert system. Then we develop an heuristic procedure to obtain an implicit local model of contacts in complex assembly tasks. Finally, a specific example of this approach — a peg-in-hole operation — is outlined.

The paper considers a general multistage stochastic decision problem which contains Markovian decision processes and multistage stochastic programming problems as special cases. The objective functions, the constraint sets and the probability measures are approximated. Making use of the Bellman Principle, (semi) convergence statements for the optimal value functions and the optimal decisions at each stage are derived. The considerations rely on stability assertions for parametric programming problems which are extended and adapted to the multistage case. Furthermore, new sufficient conditions for the convergence of objective functions which are integrals with respect to decision-dependent probability measures are presented. The paper generalizes results by Langen(1981) with respect to the convergence notions, the integrability conditions and the continuity assumptions.

We investigate the parallel complexity of merging priority queues and double-ended priority queues (priority deques, for short). The implicit data structures that implement the queues studied in this paper are the heap, the twin-heap, the min-max heap, and the deap. It is known that heaps can be merged sequentially in sublinear time whereas merging min-max heaps requires linear sequential time. In this paper, we design efficient O(log n)-time parallel algorithms to merge two priority queue or deque structures of the same type on n and k elements (n≥k), respectively, which achieves the optimal speed-up. More precisely, two heaps of sizes n and k can be merged in O(log n) time with log k processors. Moreover, a related problem of splitting a heap on n elements into two heaps of sizes k and n−k is solved in O(log n) parallel time with log n processors, which also achieves the optimal speed-up. For the merge operation on priority deques, we show that the problem of merging twin-heaps can be solved in the same complexity as that for heaps both sequential and in parallel. Algorithms for merging two min-max heaps or two deaps of sizes n and k are demonstrated, which achieves a parallel time of O(log n) with k/log n+log k processors. The study of parallel solution to the problem of merging deaps also provides us with the first serial deap merging algorithm of time complexity O(k+log n·log k). The parallel computation model used in this paper is the EREW PRAM (Exclusive-Read Exclusive-Write Parallel Random Access Machine).

In this paper we take a new look at one of the basic principles of abstract data types. Due to this principle the domain of an abstract data type must be generated by the operations. In the initial algebraic approach as well as in the loose case with initial restrictions or data constraints this principle is satisfied because of initiality resp. free construction. Actually initiality makes sure that the data under consideration are not only generated but even freely generated by the operations. In this paper we do not consider free generation but only generation leading to the new concept of algebraic specifications with generating constraints.

This paper considers the development of security policy models for networks which can operate in a multilevel security environment. We outline an abstract security policy model which addresses the access control and information flow requirements in a multilevel network. The network security policy is formulated by drawing as much parallel as possible with the computer security policy. The model is defined and the associated security requirements are given and the model is used to prove that the security conditions are not violated by the defined network operations. In developing network security policies, it is necessary to relate them to specific layers of the network architecture. We conclude this paper by outlining another network security policy model with different network subjects and objects supported by different layers in the architecture.

Stabilization of an equilibrium solution of nonlinear control systems has been extensively studied. Many elegant and important results are now available. Most of these results make use of smooth feedback to provide stabilization only within a local region containing the equilibrium. In this paper, we consider a class of nonlinear control systems, that includes nonholonomic control systems, and hence is known to present stabilization difficulties using smooth feedback. There are good theoretical and practical reasons for using hybrid feedback controllers to achieve closed loop stabilization for this class of systems. This paper presents a summary of one such hybrid feedback control approach, that guarantees global asymptotic stability. The development is a step towards a synthesis of classical nonlinear control methodology and intelligent control methodology.

This paper concerns procedural semantics for a variety of ATMSs. Reiter & de Kleer view an ATMS as a kind of abduction in which the best explanation of a formula is defined as a minimal conjunction of hypotheses that explain the formula. However, they do not give any algorithm to compute such minimal explanations of a formula in their CMS that is a generalization of de Kleer's basic ATMS. In this paper, we use the notion of characteristic clauses to make precise definitions of the CMS and the ATMS and to produce a sound and complete abductive procedure based on an extension of linear resolution. By means of this abductive procedure, we give the CMS algorithms for computing minimal explanations in the interpreted approach and for updating them in the compiled approach. We then present algorithms for generating and updating labels of nodes in an extended ATMS that accepts non-Horn justifications and literal assumptions. Finally, how a variation of the abductive procedure can be used to answer queries for circumscription of ground theories is presented.

This paper briefly reports on progress in the design and performance of a mapping system that uses laser rangefinder input to construct elevation maps of rugged, natural terrain. The paper emphasizes performance; the rationale for the design is presented elsewhere. The performance of two rangefinders is considered, and found to be the most significant limitation on the constructed maps. In addition, the accuracy and precision of the maps are quantified.

This paper examines the problem of recognizing and optimizing a class of recurrences called bounded recurrences which are a generalization of the parallel prefix problem. I show how these recurrences can be executed concurrently and examine the problem of detecting them automatically. The contribution of this paper is a framework for representing information about recurrences and examination of some structural aspects of bounded recurrences. I also examine linear recurrences in some detail showing how to generate efficient code directly from source expressions.

The management of spatial data in applications such as graphics and image processing, geography as well as computer aided design (CAD) imposes stringent new requirements on spatial database systems, in particular on efficient query processing of complex spatial objects. In this paper, we propose a two-level, multi-representation query processing technique which consists of a filter and a refinement level. The efficiency of spatial query processing is improved considerably using the following two design paradigms: first, divide and conquer, i.e. decomposition of complex spatial objects into more simple spatial components such as convex polygons, triangles or trapezoids, and second, application of efficient and robust spatial access methods for simple spatial objects. The most powerful ingredient in our approach is the concept of object decomposition. Applied to the refinement level of spatial query processing, it substitutes complex computational geometry algorithms by simple and fast algorithms for simple components. In this paper, we present four different decomposition techniques for polygonal shaped objects. The second part of the paper consists of an empirical performance comparison of those techniques using real and synthetic data sets. The four types of decomposition techniques are compared to each other and to the traditional approach with respect to the performance of spatial query processing. This comparison points out that our approach using object decomposition is superior to traditional query processing strategies.

In this paper we briefly summarize a switching approach to adaptive control which has been investigated by the authors over the last ten years. In this approach, we do not carry out plant estimation, but rather we switch between a pre-defined set of controllers in accordance with an auxiliary switching signal. We consider both the stabilization problem, and the tracking and disturbance regulation problem. The advantage of this approach is that the amount of plant uncertainty which can be tolerated is typically larger than that tolerated by traditional estimator-based adaptive controllers. In this paper we give a brief overview of our work in this area as well as a brief sketch of the historical development.

This paper discusses the techniques used to hand-parallelize, for the Alliant FX/80, four Fortran programs from the Perfect-Benchmark suite. The paper also includes the execution times of the programs before and after the transformations. The four programs considered here were not effectively parallelized by the automatic translators available to the authors. However, most of the techniques used for hand parallelization, and perhaps all of them, have wide applicability and can be incorporated into existing translators.

In this paper we propose an extension, SEDatalog, of Datalog so that sets can be naturally constructed in logic programming. In SEDatalog, sets can be defined by statements so it has a strong capability in creating sets. Three deductive rules are also introduced in this paper, which make SEDatalog strong in deductions and programming even when sets are involved in deductions. The syntactical description and the semantical interpretation of SEDatalog are comprehensively discussed in detail. The soundness and completeness theorem of SEDatalog is proved, which provides a solid foundation of SEDatalog.

Negotiation is the highlight of e-commerce and artificial intelligence. This paper applies the idea of personality to BDI models and therefore attempts to present new negotiation architecture and to illustrate the protocol and algorithm. Through the experiments this paper analyses and proves that the personality (temperament) exerts great influence on concession rates in negotiation, and therefore affects the choices of negotiation strategy.

With the rapid growth of online information, a simple search query may return thousands or even millions of results. There is a need to help user to access and identify relevant information in a flexible way. This paper describes a methodology that automatically map web search results into user defined categories. This allows the user to focus on categories of their interest, thus helping them to find for relevant information in less time. Text classification algorithm is used to map search results into categories. This paper focuses on feature selection method and term weighting measure in order to train an optimum and simple category model from a relatively small number of training texts. Experimental evaluations on real world data collected from the web shows that our classification algorithm gives promising results and can potentially be used to classify search results returned by search engines.

In this paper we discuss uncertain reasoning and decision making. Our proposal is based on the knowledge we have and entirely formalized within the so called classical two valued logic, so it has a solid foundation. Basic notions of various items are defined formally; formulas of supporting degree for uncertain reasoning and supporting degree with safety for decision making are introduced. Evaluation of "weighted facts", which represents the different importance of facts, is clearly presented within our proposal without anything else. The relation between uncertain reasoning and decision making is discussed in detail. Examples in the paper are comprehensively exhibited, which shows that our proposal is reasonable and computer-operative.

Associative classification has aroused significant attention in recent years. This paper proposed a novel interestingness measure, named dilated chi-square, to statistically reveal the interdependence between the antecedents and the consequent of classification rules. Using dilated chi-square, instead of confidence, as the primary ranking criterion for rules under the framework of popular CBA algorithm, the adapted algorithm presented in this paper can empirically generate more accurate and much more compact decision lists.

This paper presents an approach that discovers clusters of Web pages based on Web log data and Web page contents as well. Most existing Web log mining techniques are access-based approaches that statistically analyze the log data without paying much attention on the contents of the pages. The log data contains various kinds of noise which can significantly influence the performance of pure access-based web log mining. The method proposed in this paper not only considers the frequence of page co-occurrence in user access logs, but also takes into account the web page contents to cluster Web pages. We also present a method of using information entropy to prune away irrelevant papges which improves the performance of the web page clustering.

This paper deals with structured grid generation using Floater’s parametrization algorithm for surface triangulation. It gives an outline of the algorithm in the context of structured grid generation. Then it explains how the algorithm can be used to generate a structured grid over a singular NURBS surface patch. This is an alternate method to the known carpeting method of reparametrization for structured grid generation over a NURBS surface patch. The paper also explains how to generate a structured grid over a four sided trimmed patch of a facetted surface using the parametrization algorithm. All the procedures are explained using examples.

In this paper, we describe a new technique for computing a triangular mesh surface approximation to a point cloud of unorganized 3D data points. We should point out that the problem of point cloud fitting should be distinguished from that of scattered data modeling [13] Even though many of the basic techniques and tools from CAGD and multivariate approximation theory apply to both problems, they are basically different. The term “scattered data” was coined by Schumaker in his 1976 paper [27] and there was a great deal of interest and published research on (mainly) bivariate problems in the 70s and 80s. With the advent of scientific visualization along with volume visualization in the 90s, there has been growing interest in trivariate scattered data modeling [19, 21] and interest in this area continues to grow. In many respects, the problem of scattered point cloud fitting is more difficult because it is

Many problems in areas such as computer graphics, scientific visualization, computational geometry, or image processing require the computation of a distance field. The distance field indicates at each point in space the shortest distance to a given object. Depending on the problem setting, the object is described either by a voxel attribute within a volume data set or by a surface representation such as a triangle mesh. The two cases require separate approaches, and only the case of the triangle mesh is studied in this paper. Often, the distance field is needed as a regular grid of samples. The samples can be computed either in image space or object space, referring to the outer loop of the algorithm, which iterates over all samples or all triangles of the mesh, respectively. Object space methods can be competitive, especially for higher resolutions. An ideal object space method would compute a generalized Voronoi diagram (GVD) of the mesh and then scan convert its cells. At each sample location, the distance to the Voronoi site associated with the cell would yield the field value. A practical method however, avoids the expensive GVD computation and instead works with bounding polyhedra for the Voronoi cells. In this paper, we propose a new type of bounding polyhedra. This reduces the number of polyhedra and simplifies their geometry. The choice of these bounding polyhedra pays off especially if scan conversion is run on graphics hardware.

We develop a theoretical framework for constructing guaranteed quality Delaunay meshes in parallel for general two-dimensional geometries. This paper presents a new approach for constructing graded meshes, i.e., meshes with element size controlled by a user-defined criterion. The sequential Delaunay refinement algorithms are based on inserting points at the circumcenters of triangles of poor quality or unacceptable size. We call two points Delaunay-independent if they can be inserted concurrently without destroying the conformity and Delaunay properties of the mesh. The contribution of this paper is three-fold. First, we present a number of local conditions of point Delaunay-independence, which do not rely on any global mesh metrics. Our sufficient conditions of point Delaunay-independence allow to select points for concurrent insertion in such a way that the standard sequential guaranteed quality Delaunay refinement procedures can be applied in parallel to attain the required element quality constraints. Second, we prove that a quadtree, constructed in a specific way, can be used to guide the parallel refinement, so that the points, simultaneously inserted in multiple leaves, are Delaunay-independent. Third, by experimental comparison with the well-known guaranteed quality sequential meshing software, we show that our method does not lead to overrefinement, while matching its quality and allowing for code re-use.

Some important research has been undertaken in recent years on knowledge management within the CSCW community, drawing attention to the inherently social properties of knowledge and how it is shared. Much of this work has demonstrated the complex and sophisticated needs of so-called knowledge workers, and the requirement for better understandings of knowledge sharing processes. The example we present in this paper is that of knowledge work in emergency calls at SOS Alarm in Sweden, currently of interest because of a planned new system that will allow for centre-to-centre case coordination and not only within the centre. What makes such a case interesting is that workers in this context face an unlimited variety of incidents that require interpretation, decision and coordination, many of which require the deployment of local knowledge and, as importantly, have to be dealt with in a timely fashion. In this paper we focus on how a number of people work to combine their knowledge and expertise in a time effective way.

One approach to the assessment of overall opinion polarity (OvOP) of reviews, a concept defined in this paper, is the use of supervised machine learning mechanisms. In this paper, the impact of lexical feature selection and feature generalization, applied to reviews, on the precision of two probabilistic classifiers (Naive Bayes and Markov Model) with respect to OvOP identification is observed. Feature generalization based on hypernymy as provided by WordNet, and feature selection based on part-ofspeech (POS) tags are evaluated. A ranking criterion is introduced, based on a function of the probability of having positive or negative polarity, which makes it possible to achieve 100% precision with 10% recall. Movie reviews are used for training and testing the probabilistic classifiers, which achieve 80% precision.

In this paper I present a multi-agent simulation model of the development of a city. The model, CityDev, is based on agents, goods and markets. Each agent (family, industrial firm, developer, etc.) produces goods by using other goods, and trades the goods in the markets. Each good has a price, and the monetary aspects are included in the simulation. When agents produce goods and interact in the markets, the urban fabric is built and transformed. The computer model (simulator) runs on a 3-D spatial pattern organized in cubic cells. In the present paper the model is described and results are shown.

This paper discusses the social significance, theoretical rationale and methodological and technological characteristics of complex artificial environments of the 21st century. It starts by identifying a social change, the essence of which is that cities and urbanism are growing in significance, to the extent that one can speak of a second urban revolution. The paper goes on to explore urban theory and the view that cities are complex, self-organizing, artificial environments, and that the theorization of their dynamics should start from the first principles of humans’ cognitive capabilities. Finally, the paper considers the methodologies of agent base, cellular automata and advanced virtual reality simulators as tools for studying cities as self-organizing complex environments.

This paper describes the development of strong-motion observation networks constructed by the National Research Institute for Earth Science and Disaster Prevention (NIED), Japan, in the last quarter of a century. In 1974 to 1975, we first constructed a down-hole array at the IWT station, where tri-axial negative feedback accelerometers were installed at the depths of 3,510m, 108m, and free surface, respectively. Since then NIED has continued to construct various kinds of strong-motion observation networks from 1976 to 1995 (first stage) and now has operated two nation-wide networks, K-NET and KiK-net (second stage). The aim of the present paper is to show the state-of-the-art of strong-motion observation networks in Japan.

A few years ago, Jeltsch and Moloney (2002) published a review on developments in vegetation modelling. They especially stressed the importance of space (in a two-dimensional sense) as a constituent of a dynamic analysis, and of using rules rather than mathematical equations as appropriate building blocks of ecological models. Case studies were communicated where the inclusion of space led to new insights into the functioning of ecological systems. Since then a large number of papers have been published that present and apply mathematical and simulation models to plant-ecological systems: from single populations in a small area to communities on a landscape scale, from pure data description to prediction and explanation, from matrix and Markov models to individual-based models, from grasslands to forests. This increase in the number and sophistication of model papers follows a trend established in the late 1980s. Due to the stimulating effect of published examples, modelling has become increasingly popular and an integrated part of many ecological projects. Models, presented in mathematical terms, or simply verbally or graphically, are an inevitable tool for the investigation of complex systems, e.g. ecological ones. They are a means of representing reality, as determined by observation or experiment, to formulate explanatory concepts and to make predictions on the future development of the recorded area of research, possibly under changing conditions. Models must stress features that are considered to be important and must neglect other ones; this is governed by the problem in question and also by subjective judgement. As models arise from an interaction between formulation of hypotheses on the one hand and observations or experiments on the other, i.e. from a loop between brain and reality, they can never be considered as definite. Reflection on the process of modelling, on kinds and purposes of models, on their role in the discovery process and on techniques in model building

The importance of speech dialogue systems in automotive environments drastically increased in the past years. More and more applications need to be controlled by the user. Using speech interfaces to do so can improve safety during driving. However, there are special requirements to the speech dialogue in such environments. This paper will outline some of them and propose solutions. As the major topic design issues concerning the integration of speech into graphical user interfaces are discussed and the GUIDE design tool will be introduced. GUIDE was developed as a tool for designing GUIs and was recently extended to allow the simultaneous integration of speech dialogue. As we will discuss in the paper, such an integrated design is extremely important for the development of natural and intuitive human machine interfaces.

Wireless connectivity and widespread diffusion of portable devices offer novel opportunities for users to share resources anywhere and anytime, and to form ad-hoc coalitions. Resource access control is crucial to leverage these ad-hoc collaborations. In pervasive scenarios, however, collaborating entities cannot be predetermined and resource availability frequently varies, even unpredictably, due to user/device mobility, thus complicating resource access control. Access control policies cannot be defined based on entity’s identities/roles, as in traditional access control solutions, or be specified a priori to face any operative run time condition, but require continuous adjustments to adapt to the current situation. To address these issues, this paper advocates the adoption of novel access control policy models that follow two main design guidelines: context-awareness to control resource access on the basis of context visibility and to enable dynamic adaptation of policies depending on context changes, and semantic technologies for context/policy specification to allow high-level description and reasoning about context and policies. The paper also describes the design of a semantic context-aware policy model that adopts ontologies and rules to express context and context-aware access control policies and supports policy adaptation.

In a future of smart, intelligent houses where multiple heterogeneous devices will be interconnected to provide new functionalities, to enhance user productivity and to ease everyday tasks, several issues will challenge the research community, including interoperability, communication, security, hardware and interfaces. The biggest challenge will probably be maintaining the focus on the user as the ultimate target of this intense research effort. The work presented in this paper, although in a small scenario, tries to maintain the user centrality in ambient intelligence by assisting people affected by degenerative diseases such as the Motor Neuron Disease in their everyday life at home. In particular, the paper proposes an eye/head-driven application that allows to control a domotic home through an almost-standard, already existing, house gateway. The ability to follow the user through all the stages of the disease, the adoption of low cost cameras for the tracking and the ability to easily control heterogeneous devices with a single “high-level” access point are the main innovation points.

[EN] Internet of Things (IoT) has introduced new applications and environments. Smart Home provides new ways of communication and service consumption. In addition, Artificial Intelligence (AI) and deep learning have improved different services and tasks by automatizing them. In this field, reinforcement learning (RL) provides an unsupervised way to learn from the environment. In this paper, a new intelligent system based on RL and deep learning is proposed for Smart Home environments to guarantee good levels of QoE, focused on multimedia services. This system is aimed to reduce the impact on user experience when the classifying system achieves a low accuracy. The experiments performed show that the deep learning model proposed achieves better accuracy than the KNN algorithm and that the RL system increases the QoE of the user up to 3.8 on a scale of 10., This work has been partially supported by the "Ministerio de Economia y Competitividad" in the "Programa Estatal de Fomento de la Investigacion Cientifica y Tecnica de Excelencia, Subprograma Estatal de Generacion de Conocimiento" within the project under Grant TIN2017-84802-C2-1-P. This work has also been partially founded by the Universitat Polite`cnica de Vale`ncia through the postdoctoral PAID-10-20 program.

The National Geospatial-Intelligence Agency (NGA) of the USA has embarked upon the development of a new Earth Gravitational Model (EGM), to support future realizations of NGA’s World Geodetic System. Current plans call for the development of the new EGM (EGM05) by the end of 2005. The new model will be complete to degree and order 2160, and aims at a ±15 cm global Root Mean Square (RMS) geoid undulation error requirement. The new model will combine optimally the gravitational information that is extracted from dedicated geopotential mapping satellite missions (CHAMP, GRACE), with the information contained within a global gravity anomaly database of 5′×5′ resolution. This paper describes the development of a Preliminary Gravitational Model (PGM2004 A). We developed PGM2004A by combining the GRACE-only model GGM02S, with a 5′×5′ global gravity anomaly database compiled by NGA. PGM2004A is complete to degree and order 2160, and is accompanied by propagated error maps at 5′×5′ resolution, accounting for the entire bandwidth of the model (from degree 2 to degree 2160), for various model-derived gravimetric quantities (Δg, N, ξ, η). We have evaluated PGM2004A through comparisons with independent data including GPS/Leveling data, astronomic deflections of the vertical over the conterminous US (CONUS), and altimeter data from TOPEX. The results of these comparisons indicate that the goal set for EGM05 is well within reach. We summarize in this paper our current status and technical accomplishments, and discuss briefly our next steps towards the development of EGM05.

This paper outlines the development of product analysis procedures for manufacture, service and environmental performance. The paper further describes how these procedures can be integrated to give a predictive assessment of the life cycle performance of products. This integration enables design teams to evaluate design proposals and effect design changes to meet the specific life cycle goals that are judged to be the most important for the particular product under consideration.

This paper deals with a cooperation form of highly directed multi-agent systems (DMAS), where a coordinated play takes more important role than conventional MAS. We propose a concept of subjective distance, which is a sense of distance subjectively perceived by a directed agent. This paper formulates the subjective distance and empirically verifies proposed concept with actual canoe polo players.

Neural networks, fuzzy controls, and evolutionary computation have been used for behavior learning of robots in unknown and/or dynamic environment [14]. However, it is very di cult to design the learning structure of a robot beforehand, because the dynamics of the environment is unknown. Consequently, the robot should have a high learning capability to deal with the spatio-temporal context of the facing environment. Therefore, this paper proposes a fuzzy spiking neural network (FSNN) [5] for behavior learning of a mobile robot. The Hebbian learning can be used for updating the weights of FSNN. Furthermore, the network topology should be adaptive to the environmental conditions, and so, a steady-state genetic algorithm (SSGA) is applied for deciding the network topology as a combinatorial optimization problem. In this paper, the part of fuzzy was omitted for space.

This paper discusses the principal reasons for, and prospective opportunities of, simulating financial markets using an architecture based on artificial agents. The paper then discusses in detail the design and architecture of a simulator for financial markets. The Gaia methodology was employed in the development of MAFiMSi (Multi-Agent Finanacial Market Simulator), a general-purpose finacial market simulator of a dealer-type market. MAFiMSi is implemented as a library of C++ classes that currently support a stand-alone market simulation.

SeaSpeak is “English for maritime communications.” It is a restricted, specially-designed dialect of English used in merchant shipping and accepted as an international standard. This paper discusses, in the context of SeaSpeak, two key problems in the formalization of any such restricted, specially-designed language, viz., representing the illocutionary force structure of the messages, and formalization of such reference-fixing devices from ordinary language as pointing and use of demonstratives. The paper conducts the analysis in terms of Kimbrough’s FLBC agent communication language.

This paper presents a fully formal integration of Jones’s logical theory of speech acts as signalling conventions with Kimbrough’s Formal Language for Business Communication (FLBC). The work is part of a larger programme of logicism in the context of electronic commerce. Speech acts are an especially apt subject for this programme because of their pervasiveness and importance in communication for all commerce, electronic or not. The paper demonstrates that the conventionist view of speech acts, embodied in Jones’s logical theory, fits naturally with Kimbrough’s FLBC and with the Basic Messaging Framework for business communications. Further, the paper provides an illustration of how the resulting integrated theory might be implemented in practice through logic programming.