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Abstract: This paper investigates the criteria for deciding whether two words are matrix equivalent. Certain upper diagonal matrices, generally referred to as the Parikh matrices, have been widely investigated because of their usefulness in computing the numbers of subword occurrences and thereby characterizing words by numbers. However, apart from the binary alphabet, not much is known about the properties of the matrix equivalent words, that is, words possessing the same matrix. The paper investigates both the general criteria, as well as the criteria valid in natural special cases. An exhaustive solution is obtained for ternary alphabets. [Copyright &y& Elsevier]

Abstract: This paper considers gossiping among mobile agents in graphs: agents move on the graph and have to disseminate their initial information to every other agent. We focus on self-stabilizing solutions for the gossip problem, where agents may start from arbitrary locations in arbitrary states. Self-stabilization requires (some of the) participating agents to keep moving forever, hinting at maximizing the number of agents that could be allowed to stop moving eventually. This paper formalizes the self-stabilizing agent gossip problem, introduces the quiescence number (i.e., the maximum number of eventually stopping agents) of self-stabilizing solutions and investigates the quiescence number with respect to several assumptions related to agent anonymity, synchrony, link duplex capacity, and whiteboard capacity. [Copyright &y& Elsevier]

Abstract: Automata theory provides two ways of defining an automaton: either by its transition system, defining its states and events, or by its language, the set of sequences (traces) of events in which it can engage. For many classes of automaton, these forms of definition have been proved equivalent. For example, there is a well-known isomorphism between regular languages and finite deterministic automata. This paper suggests that for (demonically) the non-deterministic automata (as treated in process algebra), the appropriate link between transition systems and languages may be a retraction rather than an isomorphism. A pair of automata, defined in the tradition of CCS by their transition systems, may be compared by a pre-ordering based on some kind of simulation or bisimulation, for example, weak, strong, or barbed. Automata defined in the tradition of CSP are naturally ordered by set inclusion of their languages (often called refinement); variations in ordering arise from different choices of basic event, including for example, refusals and divergences. In both cases, we characterise a theory by its underlying transition system and its choice of ordering. Our treatment is therefore wholly semantic, independent of the syntax and definition of operators of the calculus. We put forward a series of retractions relating the above-mentioned versions of CSP to their corresponding CCS transition models. A retraction is an injection that is (with respect to the chosen ordering) monotonic, increasing and idempotent (up to equivalence). It maps the nodes of a transition system of its source theory to those of a system that has been saturated by additional transitions. Each retraction will be defined by a transition rule, in the style of operational semantics; the proofs use the familiar technique of co-induction, often abbreviated by encoding in the relational calculus. The aim of this paper is to contribute to unification of theories of reactive system programming. More practical benefits may follow. For example, we justify a method to improve the efficiency of model checking based on simulation. Furthermore, we show how model checking of a transition network fits consistently with theorem-proving tools, which reason directly about specifications and designs that are expressed in terms of sets of sequences of observable events. [Copyright &y& Elsevier]

Abstract: It is known that linear-time temporal logic (LTL), which is an extension of classical logic, is useful for expressing temporal reasoning as investigated in computer science. In this paper, two constructive and bounded versions of LTL, which are extensions of intuitionistic logic or Nelson''s paraconsistent logic, are introduced as Gentzen-type sequent calculi. These logics, and , are intended to provide a useful theoretical basis for representing not only temporal (linear-time), but also constructive, and paraconsistent (inconsistency-tolerant) reasoning. The time domain of the proposed logics is bounded by a fixed positive integer. Despite the restriction on the time domain, the logics can derive almost all the typical temporal axioms of LTL. As a merit of bounding time, faithful embeddings into intuitionistic logic and Nelson''s paraconsistent logic are shown for and , respectively. Completeness (with respect to Kripke semantics), cut–elimination, normalization (with respect to natural deduction), and decidability theorems for the newly defined logics are proved as the main results of this paper. Moreover, we present sound and complete display calculi for and . In [P. Maier, Intuitionistic LTL and a new characterization of safety and liveness, in: Proceedings of Computer Science Logic 2004, in: Lecture Notes in Computer Science, vol. 3210, Springer-Verlag, Berlin, 2004, pp. 295–309] it has been emphasized that intuitionistic linear-time logic (ILTL) admits an elegant characterization of safety and liveness properties. The system ILTL, however, has been presented only in an algebraic setting. The present paper is the first semantical and proof-theoretical study of bounded constructive linear-time temporal logics containing either intuitionistic or strong negation. [Copyright &y& Elsevier]

Abstract: This paper discusses space–time tradeoffs associated with algorithms for the problem of detecting negative cost cycles in networks (NCCD). NCCD is one of the more ubiquitous problems in computer science and operations research, with applications ranging from program verification and real-time scheduling to image segmentation and shortest path identification. Typical algorithmic analysis, whether theoretical or empirical, focuses almost exclusively on the running time of the algorithm. However, there exist applications in which space is just as important a parameter as time is. This is especially true when the problem instances are very large, as is the case in program verification. Consequently, an algorithm that minimizes running time while ignoring the space overhead may be impractical. In this paper, we analyze a number of the more common algorithms for NCCD from the perspectives of both time and space, with a view towards providing a space–time tradeoff for the practitioner. All the algorithms discussed in this paper (with the exception of Network Simplex) run in time on a network with m arcs and n vertices; however, their space requirements range from (Stressing Algorithm) to (all the Bellman–Ford and Network Simplex variants). Our empirical results demonstrate that in the cases where space is paramount, the Stressing Algorithm is a useful alternative to the Bellman–Ford variants. [Copyright &y& Elsevier]

Abstract: In this paper, we describe EMADS, an extendible multi-agent data mining system. The EMADS vision is that of a community of data mining agents, contributed by many individuals, interacting under decentralised control to address data mining requests. EMADS is seen both as an end user application and a research tool. This paper details the EMADS vision, the associated conceptual framework and the current implementation. Although EMADS may be applied to many data mining tasks; the study described here, for the sake of brevity, concentrates on agent based data classification. A full description of EMADS is presented. [Copyright &y& Elsevier]

Abstract: In developing countries like India, the traffic on roads is highly heterogeneous in nature, with vehicles of widely varying static and dynamic characteristics. In this type of traffic, vehicles do not follow lane discipline and they move freely over the entire width of roadway based on availability of space. To study this type of complex traffic flow and associated vehicular interactions, simulation is considered as an effective tool. An object-oriented methodology (OOM) for heterogeneous traffic simulation is proposed in this paper with focus on mid-block and intersection flow modeling. The paper presents the basics and advanced features of object-oriented programming (OOP) in detail in the context of traffic flow. The sample C++ code is discussed in detail to demonstrate the implementation of OOP features, such as encapsulation, inheritance and polymorphism. The contribution of this research work is the development of software objects for various components such as vehicle, traffic, link and node. This software can be adopted for heterogeneous traffic simulation programs, in general. [Copyright &y& Elsevier]

Abstract: Many mobility models attempt to provide realistic simulation to many real world scenarios. However, existing mobility models, such as RPGM [X. Hong, M. Gerla, G. Pei, C. Chiang, A group mobility model for ad hoc wireless networks, in: Proceedings of ACM/IEEE MSWiM’99, Seattle, WA, August 1999, pp. 53–60] and others, fail to address many aspects. These limitations range from mobile node (MN) collision avoidance, obstacle avoidance, and the interaction of MNs within a group. Our research, the group force mobility model (GFMM) [S.A. Williams, D. Huang, A group force mobility model, Appeared at 9th Communications and Networking Simulation Symposium, April 2006], proposes a novel idea which introduces the concept of attraction and repulsion forces to address many of these limitations. Williams and Huang [A group force mobility model, Appeared at 9th Communications and Networking Simulation Symposium, April 2006] described some of the limitations and drawbacks that many models neglect. This model effectively simulates the interaction of MNs within a group, the interaction of groups to one another, the coherency of a group, and the avoidance of collision with groups, nodes, and obstacles. This paper provides an overview of GFMM and particularly illustrates the GFMM''s ability to avoid collision with obstacles, which is a vital property to posses in order to provide a realistic simulaition. We compare our model with the commonly used RPGM model and provide statistical assessments based on connectivity metrics such as link changed, link duration, and relative speed. All will be detailed and explained in this paper. [Copyright &y& Elsevier]

Abstract: Desk design and computer display height can affect posture and muscle activation during computer use. Amplitudes of postural variables and muscle activity during computer use do not explain the results from epidemiological studies of musculoskeletal discomfort and disorders related to computer use. The purpose of this study was to assess variability of posture and muscle activity during work with two computer display heights and book/paper, in conjunction with a curved desk designed to provide forearm support and a traditional, straight desk. 18 male and 18 female participants performed 10-min tasks involving keying, mousing, reading and writing in six desk/display conditions. 3D posture and surface emg were assessed for the final 2 min of each task. The curved desk resulted in greater postural and muscle activity variation, suggesting an advantage of this supportive surface over the straight desk. There was little difference in variability associated with the two display heights. However, greater variability of posture and muscle activity was evident with the book/paper condition. Non-touch typists had greater neck flexion variation. The design of information technology tasks and workstations can influence the short term variation in posture and muscle activity. Variation is influenced independently of mean postures and muscle amplitudes and therefore needs to be considered to adequately assess the risk of musculoskeletal disorders. [Copyright &y& Elsevier]

Abstract: This paper presents a methodology developed for a study to evaluate the state of the art of automated map generalization in commercial software without applying any customization. The objectives of this study are to learn more about generic and specific requirements for automated map generalization, to show possibilities and limitations of commercial generalization software, and to identify areas for further research. The methodology had to consider all types of heterogeneity to guarantee independent testing and evaluation of available generalization solutions. The paper presents the two main steps of the methodology. The first step is the analysis of map requirements for automated generalization, which consisted of sourcing representative test cases, defining map specifications in generalization constraints, harmonizing constraints across the test cases, and analyzing the types of constraints that were defined. The second step of the methodology is the evaluation of generalized outputs. In this step, three evaluation methods were integrated to balance between human and machine evaluation and to expose possible inconsistencies. In the discussion the applied methodology is evaluated and areas for further research are identified. [Copyright &y& Elsevier]

Abstract: This paper presents a testability enhancement technique suited for AND–EXOR based logic networks that facilitates easy detection of stuck-at and bridging faults by a universal test set. Both cascaded and tree implementations of the EXOR-part are considered. The AND–EXOR based circuit implemented with a cascaded EXOR-part requires a universal test set of size (2n +6) for an n-variable function implementation. For Generalized Reed–Muller (GRM) implementation, this test set detects all single stuck-at and bridging faults (both OR-type and AND-type) and also large number of multiple bridging faults. For an Exclusive-OR Sum-of-Products (ESOP) implementation, a few single bridging faults may remain untested under this test set, occurrence of which can be minimized by employing an appropriate design and layout technique. Next, it is shown that an AND–EXOR network with a tree-based EXOR-part can be tested for similar faults by a universal test set of size (2n +8). This paper also solves an open problem of designing a universal test for a tree-based AND–EXOR circuit. Since the EXOR-tree has depth of (), where s is the number of product terms in the given AND–EXOR expression, this tree-based design reduces the circuit delay significantly compared to cascaded EXOR implementation. In both the cases, the test set can be stored in a ROM on-chip for built-in self-test (BIST) purposes. For several benchmark circuits, the universal test set is found to be much smaller in size than the ATPG-generated test sets. [Copyright &y& Elsevier]

Abstract: Upward-closed sets of integer vectors enjoy the merit of having a finite number of minimal elements, which is behind the decidability of a number of Petri net related problems. In general, however, such a finite set of minimal elements may not be effectively computable. In this paper, we develop a unified strategy for computing the sizes of the minimal elements of certain upward-closed sets associated with Petri nets. Our approach can be regarded as a refinement of a previous work by Valk and Jantzen (in which a necessary and sufficient condition for effective computability of the set was given), in the sense that complexity bounds now become available provided that a bound can be placed on the size of a witness for a key query. The sizes of several upward-closed sets that arise in the theory of Petri nets as well as in backward-reachability analysis in automated verification are derived in this paper, improving upon previous decidability results shown in the literature. [Copyright &y& Elsevier]

Abstract: The 2-interval pattern problem, introduced in [Stéphane Vialette, On the computational complexity of 2-interval pattern matching problems Theoret. Comput. Sci. 312 (2–3) (2004) 223–249], models general problems with biological structures such as protein contact maps and macroscopic describers of secondary structures of ribonucleic acids. Given a set of 2-intervals and a model , the problem is to find a maximum cardinality subset of such that any two 2-intervals in satisfy , where is a subset of relations on disjoint 2-intervals: precedence , nest , and cross . The problem left unanswered at present is that of whether there is a polynomial time solution for the 2-interval pattern problem, when and all the support intervals of are disjoint. In this paper, we present a reduction from the clique problem to show that, in this case, the problem is NP-hard. The disjoint 2-interval pattern matching problem is to decide whether a disjoint 2-interval pattern (called the pattern) is a substructure of another disjoint 2-interval pattern (called the target). In general, the problem is NP-hard, but when there are restrictions on the form of the pattern, the problem can, in some cases, be solved in polynomial time. In particular, a polynomial time algorithm has been proposed (Gramm, WABI 2004 and IEEE/ACM TCBB 2004) for the case where the patterns are so-called crossing contact maps. In this paper we show that the problem is actually NP-hard and point out an error in the analysis of the above algorithm. 1 [1] The second part of this paper appeared in WABI’2006. [Copyright &y& Elsevier]

This paper presents a novel clustering method this is called extension genetic algorithm (EGA). The new method is a combination of extension theory and genetic algorithm (GA). In the past, we used the extension method in some clustering problems. With the method, we had to rely on experiences to set rules on classical domain and weight, which caused to increase two tedious and complicated steps in clustering processes. In order to improve this defect, the paper uses the EGA to find the best parameter of classical domain. Through the simulations, we prove that this new method can eliminate try and error adjustment of modeling parameters and increase the accuracy of clustering problems. Experimental results from three different examples, including two benchmark data sets and one practical application, verify the effectiveness and applicability of the proposed work. [Copyright &y& Elsevier]

Abstract: This paper is intended more to ask questions than give answers. Specifically, we consider models for labeling schemes, and discuss issues regarding the number of labels consulted vs. the sizes of the labels. Recently, quite a few papers studied methods for representing network properties by assigning informative labels to the vertices of a network. Consider a graph function on pairs of vertices (for example, can be the distance function). In an -labeling scheme, the labels are constructed in such a way so that given the labels of any two vertices and , one can compute the function (e.g. the graph distance between and ) just by looking at these two labels. Some very involved lower bounds for the sizes of the labels were proven. Also, some highly sophisticated labeling schemes were developed to ensure short labels. In this paper, we demonstrate that such lower bounds are very sensitive to the number of vertices consulted. That is, we show several constructions of such labeling schemes that beat the lower bounds by large margins. Moreover, as opposed to the strong technical skills that were needed to develop the traditional labeling schemes, most of our schemes are almost trivial. The catch is that in our model, one needs to consult the labels of three vertices instead of two. That is, a query about vertices and can access also the label of some third vertex ( is determined by the labels of and ). More generally, we address the model in which a query about vertices and can access also the labels of other vertices. We term our generalized model labeling schemes with queries. The main importance of this model is theoretical. Specifically, this paper may serve as a first step towards investigating different tradeoffs between the amount of labels consulted and the amount of information stored at each vertex. As we show, if all vertices can be consulted then the problem almost reduces to the corresponding sequential problem. On the other hand, consulting just the labels of and (or even just the label of ) reduces the problem to a purely distributed one. Therefore, in a sense, our model spans a range of intermediate notions between the sequential and the distributed settings. In addition to the theoretical interest, we also show cases that schemes constructed for our model can be translated to the traditional model or to the sequential model, thus, simplifying the construction for those models as well. For implementing query labeling schemes in a distributed environment directly, we point at a potential usage for some new paradigms that became common recently, such as P2P and overlay networks. [Copyright &y& Elsevier]

Abstract: In this paper, we show that it can be tested in polynomial time as to whether a scenario is an execution of a Petri net. This holds for a wide variety of Petri net classes, ranging from elementary nets to general inhibitor nets. Scenarios are given by causal structures expressing causal dependencies and concurrency among events. In the case of elementary nets and of place/transition nets, such causal structures are partial orders among transition occurrences. For several extended Petri net classes, the extension of partial orders to stratified order structures is considered. The algorithms are based on the representation of the non-sequential behavior of Petri nets by so-called token flow functions and a characterization of Petri net executions called token flow property. This property allows nontrivial transformations into flow optimization problems, which can be solved in polynomial time. The paper is a revised, consolidated and extended version of the conference papers [G. Juhás, R. Lorenz, J. Desel, Can I execute my scenario in your net?, in: G. Ciardo, P. Darondeau (Eds.), ICATPN, in: Lecture Notes in Computer Science, Springer, 2005, pp. 289–308; R. Lorenz, S. Mauser, R. Bergenthum, Testing the Executability of Scenarios in General Inhibitor Nets, in: ACSD, IEEE Computer Society, 2007, pp. 167–176] and includes parts of the habilitation thesis [R. Lorenz, Szenario-basierte Verifikation und Synthese von Perinetzen: Theorie und Anwendungen, Habilitation, 2006]. [Copyright &y& Elsevier]

Abstract: The -median problem on a tree is to find a set of vertices on that minimizes the sum of distances from ’s vertices to . In this paper, we study two generalizations of the 2-median problem, which are obtained by imposing constraints on the two vertices selected as a 2-median: one is to limit their distance while the other is to limit their eccentricity. Previously, both the best upper bounds of these two generalizations were [A. Tamir, D. Perez-Brito, J.A. Moreno-Perez, A polynomial algorithm for the -centdian problem on a tree, Networks 32 (1998) 255–262; B.-F. Wang, S.-C. Ku, K.-H. Shi, Cost-optimal parallel algorithms for the tree bisector problem and applications, IEEE Transactions on Parallel and Distributed Systems 12 (9) (2001) 888–898]. In this paper, we solve both in time. We also study cases when linear time algorithms exist for the two generalizations. For example, we solve both in linear time when edge lengths and vertex weights are all polynomially bounded integers. Furthermore, we consider the relaxation of the two generalized problems by allowing 2-medians on any position of edges, instead of just on vertices, and we give -time algorithms for them. A problem, named the tree marker problem, arises several times in our approaches to the two generalized 2-median problems, and we give an -time algorithm for this problem. We also use this algorithm to speedup an algorithm of Gupta and Punnen [S.K. Gupta, A.P. Punnen, Group center and group median of a tree, European Journal of Operational Research 65 (1993) 400–406] for the group median problem, improving the running time from to , where is the number of groups in the input. [Copyright &y& Elsevier]

Abstract: A good clustering method should provide flexible scalability on the number of dimensions as well as the size of a data set. This paper proposes a method of efficiently tracing the clusters of a high-dimensional on-line data stream. While tracing the one-dimensional clusters of each dimension independently, a technique which is similar to frequent itemset mining is employed to find the set of multi-dimensional clusters. By finding a frequently co-occurred set of one-dimensional clusters, it is possible to trace a multi-dimensional rectangular space whose range is defined by the one-dimensional clusters collectively. In order to trace such candidates over a multi-dimensional online data stream, a cluster-statistics tree (CS-Tree) is proposed in this paper. A k-depth node(k ⩽ d) in the CS-tree is corresponding to a k-dimensional rectangular space. Each node keeps track of the density of data elements in its corresponding rectangular space. Only a node corresponding to a dense rectangular space is allowed to have a child node. The scalability on the number of dimensions is greatly enhanced while sacrificing the accuracy of identified clusters slightly. [Copyright &y& Elsevier]

Abstract: Future many-core processor systems require scalable solutions that conventional architectures currently do not provide. This paper presents a novel architecture that demonstrates the required scalability. It is based on a model of computation developed in the AETHER project to provide a safe and composable approach to concurrent programming. The model supports a dynamic approach to concurrency that enables self-adaptivity in any environment so the model is quite general. It is implemented here in the instruction set of a dynamically scheduled RISC processor and many such processors form a microgrid. Binary compatibility over arbitrary clusters of such processors and an inherent scalability in both area and performance with concurrency exploited make this a very promising development for the era of many-core chips. This paper introduces the model, the processor and chip architecture and its emulation on a range of computational kernels. It also estimates the area of the structures required to support this model in silicon. [Copyright &y& Elsevier]

Abstract: The purpose of this paper is to show how the rewriting-logic-based Real-Time Maude language and tool can be used to formally model, simulate, and model check advanced wireless sensor network (WSN) algorithms. This is done by first proposing some general techniques for modeling and analyzing WSN algorithms, and then by showing how these techniques have been applied to the modeling, performance estimation, and model checking of the state-of-the-art optimal geographical density control (OGDC) density control algorithm. Wireless sensor networks in general, and the OGDC algorithm in particular, pose many challenges to their formal specification and analysis, including novel communication forms, spatial entities, time-dependent and probabilistic features, and the need to analyze both correctness and performance. We focus on Monte Carlo simulations to evaluate the performance of OGDC. Extensive simulations with up to 800 sensor nodes, and comparison with the ns-2 simulations of OGDC, indicate that Real-Time Maude simulations provide fairly accurate performance estimates of WSN algorithms. As a consequence, simulating the high-level Real-Time Maude model of a WSN algorithm eliminates the need for implementing it on a simulation tool to get a faithful estimate of its performance, while providing much greater flexibility in defining the appropriate simulation scenario; in addition, Real-Time Maude model checking can search for “corner case” bugs and evaluate best-case and worst-case performance. Some of the techniques presented in this paper are also used in an ongoing analysis effort of another state-of-the-art WSN algorithm. [Copyright &y& Elsevier]

Abstract: In this paper a proof outline logic is introduced for the partial correctness of multi-threaded object-oriented programs like in Java. The main contribution is a generalization of the Owicki& Gries proof method for shared-variable concurrency to dynamic thread creation. This paper also provides a formal justification of this generalization in terms of soundness and completeness proofs. [Copyright &y& Elsevier]

This paper presents a study carried out at the University of the Basque Country UPV/EHU with the aim of evaluating the CM-ED (concept map editor) with social education students. Concept mapping is a widely accepted technique that promotes meaningful learning. Graphically representing concepts of the learning domain and relationships between them helps students integrate new knowledge into their current cognitive structure. Due to the flexibility of computer-aided drawing graphs, several concept mapping tools have been developed and their use has been studied over the last few years. CM-ED is a multilingual and multimedia software program designed for drawing concept maps. Until recently, CM-ED had been mainly used and evaluated in computer science university degree. This paper represents a qualitative step in the evaluation of CM-ED: from technical students to students of more theoretical fields. The main characteristics of the CM-ED editor and the carried out study are presented in this paper. [Copyright &y& Elsevier]

Abstract: The recommendations described in this paper are a continuation of research previously reported in the Telematics and Informatics journal. This paper explains how the tourism organisations from sub-Saharan Africa can evolve their websites into marketing tools and how they can overcome the impediments to e-commerce adoption and usage. The recommendations also explain how the other major players within the economies of these countries can make the environment conducive for e-commerce development and growth so that the tourism organisations from this region can break into the lucrative international tourism market. The recommendations were tested by sending them to the African organisations and experts in e-commerce and tourism who have worked in, or are currently based in Africa, south of the Sahara. The results showed most organisations and experts who responded think that these recommendations will help African tourism organisations adopt and use e-commerce. African tourism organisations that intend to implement or are in the process of implementing e-commerce systems should follow the recommendations outlined in this paper to help sub-Saharan Africa reach its tourism potential. [Copyright &y& Elsevier]

Abstract: A new measure (C L) of spatial/structural landscape complexity is developed in this paper, based on the Levenshtein algorithm used in Computer Science and Bioinformatics for string comparisons. The Levenshtein distance (or edit distance) between two strings of symbols is the minimum of all possible replacements, deletions and insertions necessary to convert one string into the other. In this paper, it is shown how this measure can be applicable on raster landscape maps of any size or shape. Calculations and applications are shown on model and real landscapes. The main advantages of this measure for structural (spatial) landscape analysis are the following: it is easily applicable; it can be compared to its maximum value (depending on the grid resolution); it can be used to compare structural/spatial complexities between landscapes; it is applicable to raster landscape maps of any shape; and it can be used to calculate changes in landscape complexity over time. At the level of ecological practice, it may aid in landscape monitoring, management and planning, by identifying areas of higher structural landscape complexity, which may deserve greater attention in the process of landscape conservation. [Copyright &y& Elsevier]

Compression can be used to reduce the size of files and speeding up the transmission time over networks. However, not all compression techniques have the same features and capabilities to improve the performance of transmission over networks. This paper shows a comparison between different compression algorithms in order to improve the performance of web-services over the Internet. Nowadays, Service Oriented Architecture (SOA) being used heavily between applications as interaction between loosely coupled services, which are function independently. Therefore, fast and efficient services offered through the web services are needed. Enhancing performance of web services, would improve overall system's performance. As a result, compressing and reducing the size of SOAP messages traveling over the network, improves the webs-service performance. This paper compares the performance of web-services by compressing SOAP messages using Tagged Sub-optimal Code (TSC) and Huffman Encoding Algorithms. Experimental results show that web-services compressed using TSC speeds up the performance of web-services compared to normal web-services and web-services compressed using Huffman encoding. [ABSTRACT FROM AUTHOR]

Recommendation systems are information filtering tools that present items to users based on their preferences and behavior, for example, suggestions about scientific papers or music a user might like. Based on what we said and with the development of computer science that has started to take an interest in big data and how it is used to discover user interest, we have found a lot of research going on in the area of recommendation and there are powerful systems available. In the unsupervised learning domain, this paper introduces a novel method for creating a hybrid recommender framework that combines Collaborative Filtering with Content Based Approach and Self-Organizing Map neural network technique. By testing our system on a subset of the Movies Database, we demonstrate that our method outperforms state-of-the-art methods in terms of accuracy and precision, as well as improving the efficiency of the traditional Collaborative Filtering methodology. [ABSTRACT FROM AUTHOR]

A new school subject, Leaving Certificate Computer Science, was introduced in September 2018 into Irish schools in a period of curriculum reform and change. Drawing on concepts of teacher agency and learner agency, and viewed through a figurational sociology lens, this paper explored the realities of teaching LCCS and the role teacher agency and learner agency played in such enactment. Through a case study design, four teachers were interviewed in a focus group semi-structured manner. To delve deeper into the pedagogical approaches used in LCCS, a further one teacher and their nine students were interviewed. The findings highlight an influential relationship (positive and negative, encouraging and discouraging) between teachers' agentic decisions in their process of achieving teacher agency and the students process of achieving learner agency. The paper offers a figurational viewpoint of the relationship between teacher agency and learner agency through a constructed Figure. We explicitly argue that the responsibility should not be placed on the teacher and student in achieving agency (as a product) but it is a combination of the teacher and the students and the other interdependent relationships within their figurations, alongside contextual factors, and educational social processes, which determine the fluctuation of the process of achieving teacher and learner agency. The paper provides considerations for computer science teacher education. • Explores the relationship between teacher agency and learner agency in Computer Science subject. • Uses figurational sociology to further understand the process of achieving agency. • Qualitative research study. • Considerations provided for Computer Science teacher education. [ABSTRACT FROM AUTHOR]

• This paper reviews the Business-Management-orientated process mining (PM) literature. • PM case perspective and enhancement type deserve more attention. • PM potential should be more investigated in business functions beyond operations. • PM effectiveness in tactical and strategic decision making should be explored. • PM capabilities should tackle further sector-specific managerial issues. Process Mining is a new kind of Business Analytics and has emerged as a powerful family of Process Science techniques for analysing and improving business processes. Although Process Mining has managerial benefits, such as better decision making, the scientific literature has investigated it mainly from a computer science standpoint and appears to have overlooked various possible applications. We reviewed management-orientated literature on Process Mining and Business Management to assess the state of the art and to pave the way for further research. We built a seven-dimension framework to develop and guide the review. We selected and analysed 145 papers and identified eleven research gaps sorted into four categories. Our findings were formalised in a structured research agenda suggesting twenty-five research questions. We believe that these questions may stimulate the application of Process Mining in promising, albeit little explored, business contexts and in mostly unaddressed managerial areas. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a novel framework of error-correcting output coding (ECOC) addressing the problem of multi-class classification. By weighting the output space of each base classifier which is trained independently, the distance function of decoding is adapted so that the samples are more discriminative. A criterion generated over the Extended Pair Samples (EPS) is proposed to train the weights of output space. We first conduct empirical studies on UCI datasets to verify the presented framework with four frequently used coding matrixes and then apply it in RoboCup domain to enhance the performance of agent control. Color-based image segmentation is also tested in this paper. Experimental results show that our supervised learned decoding scheme improves the accuracy of classification significantly and betters the ball control of agents in a soccer game after learning from experience. Some properties still hold in the new framework: any classifier, as well as distance function, is still applicable. Besides, it is allowed in the new framework to implement nonlinear decoding processes using kernel tricks. [Copyright &y& Elsevier]

Abstract: The paper describes an application of artificial neural networks (ANN) for natural language text reasoning. The task of knowledge discovery in text from a database, represented with a database file consisting of sentences with similar meanings but different lexico-grammatical patterns, was solved with ANNs which recognize the meaning of the text using training files with limited dictionary. The paper features recognition algorithms of text meaning from a selected source using 3-layer ANNs. Tests of the new method have also been described. [Copyright &y& Elsevier]

Abstract: The hypercube is one of the most popular interconnection networks since it has simple structure and is easy to implement. Möbius cubes form a class of hypercube variants that give better performance with the same number of edges and vertices. In this paper, we consider embedding of meshes in Möbius cubes. The main results obtained in this paper are: (1) For , there exists a mesh that can be embedded in the -dimensional Möbius cube with dilation 1 and expansion 1. (2) For , there exists a mesh that can be embedded in the -dimensional Möbius cube with dilation 2 and expansion 1. (3) For , there are two disjoint meshes that can be embedded in the 0-type -dimensional Möbius cube with dilation 1. (4) For , there are two disjoint meshes that can be embedded in the 1-type -dimensional Möbius cube with dilation 2. Results of (1) and (3) are optimal in the sense that the dilations of the embeddings are 1. [Copyright &y& Elsevier]

Abstract: We study a generalized version of reversal bounded Turing machines where, apart from several tapes on which the number of head reversals is bounded by , there are several further tapes on which head reversals remain unrestricted, but size is bounded by (where denotes the input length). Recently [M. Grohe, C. Koch, N. Schweikardt, Tight lower bounds for query processing on streaming and external memory data, Theoretical Computer Science 380 (1–2) (2007) 199–217; M. Grohe, N. Schweikardt, Lower bounds for sorting with few random accesses to external memory, in: Proc. PODS’05, ACM Press, 2005, pp. 238–249], such machines were introduced as a formalization of a computation model that restricts random access to external memory and internal memory space. Here, each of the tapes with a restriction on the head reversals corresponds to an external memory device, and the tapes of restricted size model internal memory. We use to denote the class of all problems that can be solved by deterministic Turing machines that comply to the above resource bounds. Similarly, and , respectively, are used for the corresponding nondeterministic and randomized classes. While previous papers focused on lower bounds for particular problems, including sorting, the set equality problem, and several query evaluation problems, the present paper addresses the relations between the -classes and classical complexity classes and investigates the structural complexity of the -classes. Our main results are (1) a trade-off between internal memory space and external memory head reversals, (2) correspondences between the classes and “classical” time-bounded, space-bounded, reversal-bounded, and circuit complexity classes, and (3) hierarchies of -classes in terms of increasing numbers of head reversals on external memory tapes. [Copyright &y& Elsevier]

Abstract: Rabi and Sherman [M. Rabi, A. Sherman, An observation on associative one-way functions in complexity theory, Information Processing Letters 64 (5) (1997) 239–244; M. Rabi, A. Sherman, Associative one-way functions: A new paradigm for secret-key agreement and digital signatures, Tech. Rep. CS-TR-3183/UMIACS-TR-93-124, Department of Computer Science, University of Maryland, College Park, MD, 1993] proved that the hardness of factoring is a sufficient condition for there to exist one-way functions (i.e., p-time computable, honest, p-time noninvertible functions; this paper is in the worst-case model, not the average-case model) that are total, commutative, and associative but not strongly noninvertible. In this paper we improve the sufficient condition to . More generally, in this paper we completely characterize which types of one-way functions stand or fall together with (plain) one-way functions—equivalently, stand or fall together with . We look at the four attributes used in Rabi and Sherman’s seminal work on algebraic properties of one-way functions (see [M. Rabi, A. Sherman, An observation on associative one-way functions in complexity theory, Information Processing Letters 64 (5) (1997) 239–244; M. Rabi, A. Sherman, Associative one-way functions: A new paradigm for secret-key agreement and digital signatures, Tech. Rep. CS-TR-3183/UMIACS-TR-93-124, Department of Computer Science, University of Maryland, College Park, MD, 1993]) and subsequent papers–strongness (of noninvertibility), totality, commutativity, and associativity–and for each attribute, we allow it to be required to hold, required to fail, or “don’t care”. In this categorization there are potential types of one-way functions. We prove that each of these 81 feature-laden types stands or falls together with the existence of (plain) one-way functions. [Copyright &y& Elsevier]

Abstract: The paper describes a logical framework for handling uncertain spatial information, and merging it when it comes from multiple sources. For this purpose, we use a simple logical formalization for spatial ontologies and for property ontologies relative to different universes of discourse (these ontologies only involve subsumption and mutual exclusiveness relations), since spatial information typically associates properties to sets of parcels that are themselves described in terms of the spatial and/or property vocabularies appearing in the ontologies. Apart from the ontological information describing relations between vocabulary labels, we propose to represent a piece of spatial information as a pair, called “attributive formula”, associating a property formula to a set of parcels (represented by a spatial formula). A set of inference rules is given in order to be able to reason from these attributive pairs. Then, we examine how uncertainty can be encoded in attributive information, using possibilistic logic in a reified manner with respect to parcels. Another important issue pointed out in this paper is that there are two ways to link a property to an area. A first meaning is that the property is true everywhere in the area, a second meaning is that the property is at least true somewhere in the area. This distinction is necessary in order to be able to use both ontological information (which can be encoded by “everywhere” attributive-formulas) and attributive information (which contain the two kinds of attributive-formulas). Lastly, the paper studies how information fusion problems can be handled in the context of spatial data. The problems encountered do not come only from the uncertainty and the possible inconsistency of information as in any information fusion situations, but also from the fact that sources may use different space partitions and may not explicitly specify the somewhere or everywhere reading associated to the information. [Copyright &y& Elsevier]

Abstract: Dualization of a monotone Boolean function represented by a conjunctive normal form (CNF) is a problem which, in different disguise, is ubiquitous in many areas including Computer Science, Artificial Intelligence, and Game Theory to mention some of them. It is also one of the few problems whose precise tractability status (in terms of polynomial-time solvability) is still unknown, and now open for more than 25 years. In this paper, we briefly survey computational results for this problem, where we focus on the famous paper by Fredman and Khachiyan [On the complexity of dualization of monotone disjunctive normal forms, J. Algorithms 21 (1996) 618–628], which showed that the problem is solvable in quasi-polynomial time (and thus most likely not co-NP-hard), as well as on follow-up works. We consider computational aspects including limited nondeterminism, probabilistic computation, parallel and learning-based algorithms, and implementations and experimental results from the literature. The paper closes with open issues for further research. [Copyright &y& Elsevier]

Abstract: This paper studies local algorithms for autonomous robot systems, namely, algorithms that use only information of the positions of a bounded number of their nearest neighbors. The paper focuses on the spreading problem. It defines measures for the quality of spreading, presents a local algorithm for the one-dimensional spreading problem, proves its convergence to the equally spaced configuration and discusses its convergence rate in the synchronous and semi-synchronous settings. It then presents a local algorithm achieving the exact equally spaced configuration in finite time in the synchronous setting, and proves it is time optimal for local algorithms. Finally, the paper also proposes a possible algorithm for the two-dimensional case and presents partial simulation results of its effectiveness. [Copyright &y& Elsevier]

Abstract: In an earlier paper [Fukushima, K., & Tohyama, K. (2005). Analysis of optic flow: a neural network model. In ICONIP 2005, International Conference on Neural Information Processing (pp. 312–317); Tohyama, K., & Fukushima, K. (2005). Neural network model for extracting 98 optic flow. Neural Networks, 18(5–6), 549–556], we proposed a neural network extracting optic flow based on vector field hypothesis. We started discussion there, however, from the stage where local velocities of visual objects have already been extracted. This paper proposes a new mechanism of extracting local velocity from retinal images, and adds it to the previous network. The network has a hierarchical multilayered architecture. X- and Y-cells of the retina extract spatial and temporal contrast of brightness. The network contains several types of V1 cells, namely, S- C- and V-cells. S- and C-cells extract orientated edges. V-cells extract local velocities, based on the signals from Y- and S-cells. MT cells extract relative velocities between adjoining small visual fields. MST cells add the responses of MT cells to extract a specific optic flow, such as rotation and expansion/contraction. The difference in type of optic flow extracted by MST cells can be created simply by the difference in relative locations of inhibitory to excitatory areas in the receptive fields of MT cells. [Copyright &y& Elsevier]

Abstract: This paper deals with the inferrability of classes of E-pattern languages–also referred to as extended or erasing pattern languages–from positive data in Gold’s model of identification in the limit. The first main part of the paper shows that the recently presented negative result on terminal-free E-pattern languages over binary alphabets does not hold for other alphabet sizes, so that the full class of these languages is inferrable from positive data if and only if the corresponding terminal alphabet does not consist of exactly two distinct letters. The second main part yields the insight that the positive result on terminal-free E-pattern languages over alphabets with three or four letters cannot be extended to the class of general E-pattern languages. With regard to larger alphabets, the extensibility remains open. The proof methods developed for these main results do not directly discuss the (non-)existence of appropriate learning strategies, but they deal with structural properties of classes of E-pattern languages, and, in particular, with the problem of finding telltales for these languages. It is shown that the inferrability of classes of E-pattern languages is closely connected to some problems on the ambiguity of morphisms so that the technical contributions of the paper largely consist of combinatorial insights into morphisms in word monoids. [Copyright &y& Elsevier]

Abstract: In this paper, we study the inferability of term rewriting systems (trss, for short) from positive examples alone. Two classes of trss inferable from positive data are presented, namely, simple flat trss and linear-bounded trss. These classes of trss are rich enough to include many divide-and-conquer programs 1 [1] We use ‘programs’ and ‘systems’ interchangeably as trss are very similar to functional programs. In fact, the trss considered in this paper follow the so called constructor discipline and are essentially functional programs. like addition, doubling, logarithm, tree-count, list-count, split, append, reverse, etc. The classes of simple flat trss and linear-bounded trss are incomparable, i.e., there are functions that can be computed by simple flat trss but not by linear-bounded trss and vice versa. [Copyright &y& Elsevier]

Abstract: Physical-layer (pulse-coupled) techniques for distributed synchronization in wireless networks are attracting significant attention for their efficiency and scalability. In this paper, the model of pulse-coupled discrete Phase Locked Loops is reviewed and further investigated in two directions. At first, we extend the characterization of (frequency or phase) synchronous states and convergence conditions from homogeneous networks, where all the nodes have the same power constraints, to more general heterogeneous networks. Towards this goal, we build on recent results on algebraic graph theory for generally non-bidirectional graphs, and derive: (i) necessary and sufficient conditions for global synchronization of the network; (ii) closed-form expressions for the asymptotic values of frequency and phases, as a function of the network topology. In the second part of the paper, an application of pulse-coupled synchronization is considered, namely data collection in a sensor network. The energy efficiency of two medium access protocols for data collection from a set of randomly located sensors to an access point is compared: (i) basic ALOHA (which does not require time synchronization among the sensors); (ii) slotted ALOHA, where time synchronization is achieved via pulse-coupled clocks. Analysis shows that the energy spent for maintaining synchronization in slotted ALOHA pays off in terms of total energy consumption with respect to basic ALOHA provided that the number of sensors is sufficiently small. Moreover, the energy gain is proved to depend explicitly on the system load (in terms of packets /s), hardware and topology of the network. [Copyright &y& Elsevier]

Abstract: In this paper, we generalize the rectangular nonconforming Wilson element method proposed in [Z. Zhang, S. Zhang, Wilson element for the Reissner–Mindlin plate,Comput. Methods Appl. Mech. Engrg. 113 (1994) 55–65] for the Reissner–Mindlin plate problem to the general quadrilateral mesh and analyze the error. It is proved that this method converges at uniformly optimal rates with respect to both the energy and norms. These estimates improve those of [Z. Zhang, S. Zhang, Wilson element for the Reissner–Mindlin plate, Comput. Methods Appl. Mech. Engrg. 113 (1994) 55–65] in the sense that the requirement of regularity on the solution is dropped, and that the error estimate of this scheme is analyzed. The numerical examples at the end of this paper demonstrate the superiority of this method over the MITC4 [K.J. Bathe, E. Dvorkin, A four-node plate bending element based on Mindlin–Reissner plate theory and a mixed interpolation, Int. J. Numer. Methods Engrg. 21 (1985) 367–383]. [Copyright &y& Elsevier]

Abstract: Associative-classification is a promising classification method based on association-rule mining. Significant amount of work has already been dedicated to the process of building a classifier based on association rules. However, relatively small amount of research has been performed in association-rule mining from multi-label data. In such data each example can belong, and thus should be classified, to more than one class. This paper aims at the most demanding, with respect to computational cost, part in associative-classification, which is efficient generation of association rules. This task can be achieved using different frequent pattern mining methods. In this paper, we propose a new method that is based on the state-of-the-art tree-projection-based frequent pattern mining algorithm. This algorithm is modified to improve its efficiency and extended to accommodate the multi-label recurrent-item associative-classification rule generation. The proposed algorithm is tested and compared with A priori-based associative-classification rule generator on two large datasets. [Copyright &y& Elsevier]

Abstract: Adaptivity in process management systems is key to their successful applicability in practice. Approaches have been already developed to ensure system correctness after arbitrary process changes at the syntactical level (e.g., avoiding inconsistencies such as deadlocks or missing input parameters after a process change). However, errors may be still caused at the semantical level (e.g., violation of business rules). Therefore, the integration and verification of domain knowledge will flag a milestone in the development of adaptive process management technology. In this paper, we introduce a framework for defining semantic constraints over processes in such a way that they can express real-world domain knowledge on the one hand and are still manageable concerning the effort for maintenance and semantic process verification on the other hand. This can be used to detect semantic conflicts (e.g., drug incompatibilities) when modeling process templates, applying ad hoc changes at process instance level, and propagating process template modifications to already running process instances, even if they have been already individually modified themselves; i.e., we present techniques to ensure semantic correctness for single and concurrent changes which are, in addition, minimal regarding the set of semantic constraints to be checked. Together with further optimizations of the semantic checks based on certain process meta model properties this allows for efficiently verifying processes. Altogether, the framework presented in this paper provides the basis for process management systems which are adaptive and semantic-aware at the same time. [Copyright &y& Elsevier]

Abstract: The paper approaches the classical combinatorial problem of freeness of words, in the more general case of partial words. First, we propose an algorithm that tests efficiently whether a partial word is -free or not, for a given . Then, we show that there exist arbitrarily many -free infinite partial words, over a binary alphabet, containing an infinite number of holes, for . Moreover, we present an efficient algorithm for the construction of a cube-free partial word with a given number of holes, over a binary alphabet. In the final section of the paper, we show that there exists an infinite word, over a four-symbol alphabet, in which we can substitute randomly one symbol with a hole, and still obtain a cube-free word; we show that such a word does not exist for alphabets with fewer symbols. Further, we prove that in this word we can replace arbitrarily many symbols with holes, such that each two consecutive holes are separated by at least two symbols, and obtain a cube-free partial word. This result seems interesting because any partial word containing two holes with less than two symbols between them is not cube-free. Finally, we modify the previously presented algorithm to construct, over a four-symbol alphabet, a cube-free partial word with exactly holes, having minimal length, among all the possible cube-free partial words with at least holes. [Copyright &y& Elsevier]

Abstract: Katriel and Bodlaender [Irit Katriel, Hans L. Bodlaender, Online topological ordering, ACM Transactions on Algorithms 2 (3) (2006) 364–379] modify the algorithm proposed by Alpern et al. [Bowen Alpern, Roger Hoover, Barry K. Rosen, Peter F. Sweeney, F. Kenneth Zadeck, Incremental evaluation of computational circuits, in: Proceedings of the First Annual ACM–SIAM Symposium on Discrete Algorithms (SODA), 1990, pp. 32–42] for maintaining the topological order of the nodes of a directed acyclic graph while inserting edges and prove that their algorithm runs in time and has an lower bound. In this paper, we give a tight analysis of their algorithm by showing that it runs in time 1 [1] In this paper, we assume that . In fact, our analysis can be easily extended to prove that the algorithm runs in time without the assumption . . [Copyright &y& Elsevier]

Abstract: In this paper we present an empirical Bayes method for flexible and efficient independent component analysis (ICA). The method is flexible with respect to choice of source prior, dimensionality and constraints of the mixing matrix (unconstrained or non-negativity), and structure of the noise covariance matrix. Parameter optimization is handled by variants of the expectation maximization (EM) algorithm: overrelaxed adaptive EM and the easy gradient recipe. These retain the simplicity of EM while converging faster. The required expectations over the source posterior, the sufficient statistics, are estimated with mean field methods: variational and the expectation consistent (EC) framework. We describe the derivation of the EC framework for ICA in detail and give empirical results demonstrating the improved performance. The paper is accompanied by the publicly available Matlab toolbox icaMF. [Copyright &y& Elsevier]

Abstract: Feature transformation aims to reduce the effects of channel- and handset-distortion in telephone-based speaker verification. This paper compares several feature transformation techniques and evaluates their verification performance and computation time under the 2000 NIST speaker recognition evaluation protocol. Techniques compared include feature mapping (FM), stochastic feature transformation (SFT), blind stochastic feature transformation (BSFT), feature warping (FW), and short-time Gaussianization (STG). The paper proposes a probabilistic feature mapping (PFM) in which the mapped features depend not only on the top-1 decoded Gaussian but also on the posterior probabilities of other Gaussians in the root model. The paper also proposes speeding up the computation of PFM and BSFT parameters by considering the top few Gaussians only. Results show that PFM performs slightly better than FM and that the fast approach can reduce computation time substantially. Among the approaches investigated, the fast BSFT (fBSFT) strikes a good balance between computational complexity and error rates, and FW and STG are the best in terms of error rates but with higher computational complexity. It was also found that fusion of the scores derived from systems using fBSFT and STG can reduce the error rate further. This study advocates that fBSFT, FW, and STG have the highest potential for robust speaker verification over telephone networks because they achieve good performance without any a priori knowledge of the communication channel. [Copyright &y& Elsevier]

Abstract: This paper introduces a novel genetic algorithm whose features have been purposely designed to be suited to hardware implementation. This is distinct from previous hardware designs that have been realized directly from conventional genetic algorithm approaches. To be suitable for hardware implementation, we propose that a genetic algorithm should attempt to both minimize final layout dimensions and reduce execution time while remaining a valid implementation. Consequently, the new genetic algorithm specifically aims to keep the requisite silicon area to a minimum by incorporating a monogenetic strategy that retains only the optimal individual, resulting in a dramatic reduction in the memory requirement and obviating the need for crossover circuitry. The results given in this paper demonstrate that new approach improves on a number of existing hardware genetic algorithm implementations in terms of the quality of the solution produced, the calculation time and the hardware component requirements. [Copyright &y& Elsevier]

In this paper, we present a new technique for worst-case analysis of compression algorithms which are based on the Burrows–Wheeler Transform. We mainly deal with the algorithm proposed by Burrows and Wheeler in their first paper on the subject [M. Burrows, D.J. Wheeler, A block sorting lossless data compression algorithm, Technical Report 124, Digital Equipment Corporation, Palo Alto, California, 1994], called bw0. This algorithm consists of the following three essential steps: (1) Obtain the Burrows–Wheeler Transform of the text, (2) Convert the transform into a sequence of integers using the move-to-front algorithm, (3) Encode the integers using Arithmetic code or any order-0 encoding (possibly with run-length encoding). We achieve a strong upper bound on the worst-case compression ratio of this algorithm. This bound is significantly better than bounds known to date and is obtained via simple analytical techniques. Specifically, we show that for any input string , and , the length of the compressed string is bounded by where is the th order empirical entropy, is a constant depending only on and on the size of the alphabet, and is the standard zeta function. As part of the analysis, we prove a result on the compressibility of integer sequences, which is of independent interest. Finally, we apply our techniques to prove a worst-case bound on the compression ratio of a compression algorithm based on the Burrows–Wheeler Transform followed by distance coding, for which worst-case guarantees have never been given. We prove that the length of the compressed string is bounded by . This bound is better than the bound we give for bw0. [Copyright &y& Elsevier]

Abstract: This paper discusses how to bridge the gap between foresight research oriented to the long-term, and traditional market research oriented to the medium to short term, when applied to an early stage of a technology''s life cycle. It proposes using an integrating approach, i.e. a combination of methods and both foresight and traditional market research. A mix of complementary methods for the acquisition and analysis of data is presented in a case study. This helps to overcome the deficits of some qualitative foresight methods and quantitative methods often used in traditional market research and allows us to examine research results from the different methods applied both on their own and as a group. In the absence of a single fully-fledged and accepted economic approach, this paper argues that combined market research and foresight modules are the best possible approach for analyzing the economic potential of emerging technologies like nanotechnology. In the future, similar applications of such market foresight modules may be useful, for example, as elements of foresight. They will also be useful in studies of emerging technologies (e.g. converging technologies, cognitive science and Web 2.0) where traditional market research does not produce a realistic market assessment. [Copyright &y& Elsevier]