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The NHS England Radiotherapy Service Specification calls for routine use of patient-reported outcome measures (PROMs). However, barriers exist at patient, healthcare professional and service levels. The aim of the present study was to determine the current use of PROMs within radiotherapy services in England. The current attitudes, barriers and enablers to the implementation of PROMs in radiotherapy practice were evaluated and practical recommendations to inform future implementation were developed. A mixed-methods approach was adopted to obtain quantitative and qualitative data. An online questionnaire was developed and disseminated to all radiotherapy operational delivery network managers across England. The questionnaire consisted of 12 open and closed questions relating to PROMs use, with the option to provide free-text responses. Inductive thematic analysis was conducted on free-text comments, whereas descriptive statistics were used to analyse quantitative data. In total, 182 responses were received from 40 of the 50 radiotherapy providers, resulting in a response rate of 84%. The current use of PROMs was analysed, including rationale for use, tools used, format of PROMs collection and timing within the radiotherapy pathway. Most respondents indicated that PROMs were used in the context of clinical trials only. Through thematic analysis, four identical key themes were identified relating to both barriers and enablers to PROMs use; these included IT infrastructure, time, human/financial resources and training/education. A fifth theme, standardisation, was identified as a key enabler to PROMs use. Our findings show that outside of clinical trials, PROMs are not routinely used in radiotherapy services due to barriers identified at professional and service levels. Here we provide recommendations to mitigate the barriers identified and implement PROMs in radiotherapy, including training for healthcare professionals and standardisation of PROMs tools and storage. This study provides a key first step in driving PROMs implementation within radiotherapy services across England. • Outside of clinical trials, PROMs were not widely used within radiotherapy services. • Common PROMs used included QOL, anxiety/depression and urinary/bowel function tools. • PROMs are completed using either paper or electronic forms, by staff or patients. • Barriers include IT infrastructure, time, resources (staff/finances) and training. • Enablers included IT, time, resources, training and standardisation. [ABSTRACT FROM AUTHOR]

This is the second of two papers reporting the development of a spiritual care competency framework for pre-registration nurses and midwives as part of a PhD study using an embedded sequential mixed methods eclectic research design. The first paper outlines how 116 competency items were generated from an in-depth review of international literature, and offers a theoretical model to underpin development of the Framework. This paper reports how the Framework was developed. Method/Results: Five focus groups were held with stakeholders in Malta (chaplains/spiritual leaders, undergraduate nursing/midwifery educators, qualified nurses/midwives, parents/carers, patients/clients) to ensure that aspects of spirituality/spiritual care important to them, but not identified in the literature review, were included in the Framework. The resulting 55 competencies in seven domains formed the Delphi Questionnaire which was validated using a two round modified Delphi method involving experts from Malta. The final seven domain 54 item Framework demonstrated good to strong internal consistency, stability and a good fit with a six factor model. The Framework's greatest immediate contribution is in its ability to inform undergraduate nursing/midwifery spiritual care curriculum design and delivery. Further development of the Framework could assist in student selection ensuring that the 'art' of nursing/midwifery has parity with the 'science'. • This is the first pre-registration Spiritual Care Competency Framework for nurses/midwives. • It was developed using a rigorous embedded sequential mixed methods eclectic research design. • The Framework is informing design/delivery of spiritula care education programmes across Europe [ABSTRACT FROM AUTHOR]

This paper proposes a methodology for identifying data samples that are likely to be mislabeled in a c -class classification problem (dataset). The methodology relies on an assumption that the generalization error of a model learned from the data decreases if a label of some mislabeled sample is changed to its correct class. A general classification model used in the paper is OP-ELM; it also provides a fast way to estimate the generalization error by PRESS Leave-One-Out. It is tested on two toy datasets, as well as on real life datasets for one of which expert knowledge about the identified potential mislabels has been sought. [ABSTRACT FROM AUTHOR]

Finding heavy-elements (heavy-hitters) in streaming data is one of the central, and well-understood tasks. Despite the importance of this problem, when considering the sliding windows model of streaming (where elements eventually expire) the problem of finding L 2 -heavy elements has remained completely open despite multiple papers and considerable success in finding L 1 -heavy elements. Since the L 2 -heavy element problem doesn't satisfy certain conditions, existing methods for sliding windows algorithms, such as smooth histograms or exponential histograms are not directly applicable to it. In this paper, we develop the first polylogarithmic-memory algorithm for finding L 2 -heavy elements in the sliding window model. Our technique allows us not only to find L 2 -heavy elements, but also heavy elements with respect to any L p with 0 < p ≤ 2 on sliding windows. By this we completely “close the gap” and resolve the question of finding L p -heavy elements in the sliding window model with polylogarithmic memory, since it is well known that for p > 2 this task is impossible. We demonstrate a broader applicability of our method on two additional examples: we show how to obtain a sliding window approximation of the similarity of two streams, and of the fraction of elements that appear exactly a specified number of times within the window (the α -rarity problem). In these two illustrative examples of our method, we replace the current expected memory bounds with worst case bounds. [ABSTRACT FROM AUTHOR]

Smart City is a recent concept that is gaining momentum in public opinion, and thus, it is making its way into the agendas of researchers and city authorities all over the world. However, there is no consensus of what exactly is a smart city, and academic research is, at best, building applications in numerous silos. This paper explores the computer science and information technology literature about Smart City. Using data analysis techniques, we contribute to present the domain from an objective data-based point of view, aiming to highlight its major trends, and providing a single entry point for newcomers. • Smart city concept is rapidly evolving and gaining attention worldwide. • Most smart city publications remained uncited by related literature. • Smart people and economy applications present opportunities for future research. • Identifying most influential works and discussing existing and open issues [ABSTRACT FROM AUTHOR]

Informatics or computer science (the terms informatics and computer science are used as synonyms in this paper) in Austrian secondary schools is often considered “difficult” and “not interesting” because of mainly mathematical and economical contents. But informatics is much more; it is used in almost every part of the working life and can also cooperate with every subject at school. It offers a wide range of possibilities for COOL (COoperative Open Learning), an Austrian teaching model based on the Dalton Plan that provides also cooperation between different subject matters. Besides the COOL concept this paper describes some ideas for cooperation between informatics and foreign languages at secondary schools and at University level besides just ICT (Information and Communication Technology) or computer-assisted language learning. The presented tasks are part of the project “COOL Informatics” (according to COoperative Open Learning) that aims at developing COOL teaching material based on neurodidactical (Neurodidactics is a relatively young research field that combines the findings of brain research, pedagogy, cognitive psychology and other related fields.) principles for informatics and cross-curricular cooperation from primary school up to University. On the basis of the developed material the following main research questions of the project shall be examined in the course of the next school year: (1) Can COoperative Open Learning methods help to enhance learning? (2) Can learning be enhanced by considering neurodidactical principles in the design of teaching material and in the classroom? As the first test phase of the developed material is still in progress the evaluation is not available at the moment. But the first informal feedback of a vocational school and a programming course at the University shows that it is worth fostering COoperative Open Learning and cross-curricular cooperation. [Copyright &y& Elsevier]

Abstract: Cloud computing is actually a model for enabling convenient, limitless, on demand network access to a shared pool of computing resource. This paper describes some aspect of cloud architecture including cloud based information mechanism, especially useful in information system. Paper mention about the challenges and opportunities of cloud based model. At last we mental the main SWOT in respect of information delivery mechanism. [Copyright &y& Elsevier]

Abstract: Biology databases (bioDBs) play an ever-increasing role in the post-genome era for bioinformatics education. In order to handle the increasing demand for bioDBs in bioinformatics education, since Spring 2005, the College of Information Science and Technology (IST) at University of Nebraska at Omaha (UNO) has offered a course entitled “Database Search and Pattern Discovery” for seniors of our undergraduate Bioinformatics program (which is also available for graduate students majored in Compute Science program) on an annual base. This paper summarizes considerations behind development of this course, describes how the course is structured, reports our findings and observations, and raises issues of urgent tasks. The main objective of this paper is to exchange our thoughts of bioinformatics course development and solicit feedbacks and suggestions from colleagues working in bioinformatics education and related fields. [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: 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: Through experiments, this paper investigates the compatibility of information types with the diagnostic strategy in information aid. Compatibility with operator strategies is an important requirement for information aiding systems in nuclear power plants (NPPs). This paper used three typical types of information aids for MCR operators to investigate the effect of the aids on diagnostic strategies: “alarm (A),” “hypothesis on faults (H),” and “hypothesis on faults and expected symptoms (HS).” The experimental results indicate that the effectiveness of information aid types can vary, dependent on the strategies subjects employ. The results also show that the HS aid improved the diagnosis performance in the hypothesis-and-test strategy. [Copyright &y& Elsevier]

After reporting on characteristics, structure and contents of the specialised informatics-based curriculum for medical informatics (MI) at the University of Heidelberg/University of Applied Sciences Heilbronn, the paper describes the development during the last 5 years, and in particular a complementary health care oriented postgraduate program in ‘Health Information Management’ (IM). Furthermore, it outlines results of a study among the MI graduates, which aims to assess their job situation and to evaluate the curriculum from their viewpoint and so establishes a summary of 30 years of experience with the program. Finally, the paper discusses new challenges of the program, considering the results of the study, perspectives of health care provision in the next decade, content changes to be focused on and the growing competition in the field of programs for medical informatics. [Copyright &y& Elsevier]

The discovery and analysis of community structure in complex networks is a hot issue in recent years. In this paper, based on the fast greedy clustering algorithm CNM with the thought of local search, the introduction of the idea of node centrality and the optimal division of the central nodes and their neighbor nodes into correct communities, a new algorithm CNM-Centrality of detecting communities in complex networks is proposed. In order to verify the accuracy and efficiency of this algorithm, the performance of this algorithm is tested on several representative real-world networks and a set of computer-generated networks by LFR-benchmark. The experimental results indicate that this algorithm can identify the communities accurately and efficiently. Furthermore, this algorithm can also acquire higher values of modularity and NMI than the CNM, Infomap, Walktrap algorithms do. [ABSTRACT FROM AUTHOR]

In this paper, we present a new approach to server consolidation in heterogeneous computer clusters using Colored Petri Nets (CPNs). Server consolidation aims to reduce energy costs and improve resource utilization by reducing the number of servers necessary to run the existing virtual machines in the cluster. It exploits the emerging technology of live migration which allows migrating virtual machines between servers without stopping their provided services. Server consolidation approaches attempt to find migration plans that aim to minimize the necessary size of the cluster. Our approach finds plans which not only minimize the overall number of used servers, but also minimize the total data migration overhead. The latter objective is not taken into consideration by other approaches and heuristics. We explore the use of CPN Tools in analyzing the state spaces of the CPNs. Since the state space of the CPN model can grow exponentially with the size of the cluster, we examine different techniques to generate and analyze the state space in order to find good plans to server consolidation within acceptable time and computing power. [ABSTRACT FROM AUTHOR]

The advice complexity of an online problem describes the additional information both necessary and sufficient for online algorithms to compute solutions of a certain quality. In this model, an oracle inspects the input before it is processed by an online algorithm. Depending on the input string, the oracle prepares an advice bit string that is accessed sequentially by the algorithm. The number of advice bits that are read to achieve some specific solution quality can then serve as a fine-grained complexity measure. The main contribution of this paper is to study a powerful method for proving lower bounds on the number of advice bits necessary. To this end, we consider the string guessing problem as a generic online problem and show a lower bound on the number of advice bits needed to obtain a good solution. We use special reductions from string guessing to improve the best known lower bound for the online set cover problem and to give a lower bound on the advice complexity of the online maximum clique problem. [ABSTRACT FROM AUTHOR]

This paper presents a practical decision procedure for Propositional Projection Temporal Logic with infinite models. First, a set Prop l of labels l i , 0 ⩽ i ⩽ n ∈ N 0 , is used to mark nodes of an LNFG of a formula, and a node with l i is treated as an accepting state as in an automaton. Further, the generalized Büchi accepting condition for automata is employed to identify a path (resulting a word) in an LNFG as a model of the formula. In addition, the implementation details of the decision procedure and relevant algorithms including pre-processing, LNFG, circle finding algorithms are presented; as a matter of fact, all algorithms are implemented by C++ programs. [ABSTRACT FROM AUTHOR]

The Maximum Agreement Forest problem ( MAF ) asks for a largest common subforest of a collection of phylogenetic trees. The MAF problem on two binary phylogenetic trees has been studied extensively in the literature. In this paper, we present a group of fixed-parameter tractable algorithms for the MAF problem on multiple (i.e., two or more) binary phylogenetic trees. Our techniques work fine for the problem for both rooted trees and unrooted trees. The computational complexity of our algorithms is comparable with that of the known algorithms for two trees, and is independent of the number of phylogenetic trees for which a maximum agreement forest is constructed. [ABSTRACT FROM AUTHOR]

Given a connected outerplanar graph G of pathwidth p , we give an algorithm to add edges to G to get a supergraph of G , which is 2-vertex-connected, outerplanar and of pathwidth O ( p ) . This settles an open problem raised by Biedl [1] , in the context of computing minimum height planar straight line drawings of outerplanar graphs, with their vertices placed on a two-dimensional grid. In conjunction with the result of this paper, the constant factor approximation algorithm for this problem obtained by Biedl [1] for 2-vertex-connected outerplanar graphs will work for all outer planar graphs. [ABSTRACT FROM AUTHOR]

Highlights: [•] A new method for environmental impact assessment is proposed. [•] The proposed method is more effective by considering various types of uncertainty. [•] A new representation of uncertain information, called D numbers, is presented. [•] This paper provides a new framework for the environmental impact assessment. [Copyright &y& Elsevier]

Abstract: In particle swarm optimization (PSO), the particle position vectors denotes the potential solutions of the problem. The position vectors are updated from the information of the global best particle and the personal best particles. When all particles gather to one position, the search process does not evolve any more. For overcoming this diffculty, this paper focuses on the use of the second best particle information. The present algorithm uses second global best or second personal best particles in addition to first global best and first personal best particles. The present algorithms are compared with the original PSO algorithm in the solution problem of test functions. The results show that the use of the second best particles can improve the search performance of the original PSO algorithm. [Copyright &y& Elsevier]

Abstract: Automatic Text Summarization has been shown to be useful for Natural Language Processing tasks such as Question Answering or Text Classification and other related fields of computer science such as Information Retrieval. Since Geographical Information Retrieval can be considered as an extension of the Information Retrieval field, the generation of summaries could be integrated into these systems by acting as an intermediate stage, with the purpose of reducing the document length. In this manner, the access time for information searching will be improved, while at the same time relevant documents will be also retrieved. Therefore, in this paper we propose the generation of two types of summaries (generic and geographical) applying several compression rates in order to evaluate their effectiveness in the Geographical Information Retrieval task. The evaluation has been carried out using GeoCLEF as evaluation framework and following an Information Retrieval perspective without considering the geo-reranking phase commonly used in these systems. Although single-document summarization has not performed well in general, the slight improvements obtained for some types of the proposed summaries, particularly for those based on geographical information, made us believe that the integration of Text Summarization with Geographical Information Retrieval may be beneficial, and consequently, the experimental set-up developed in this research work serves as a basis for further investigations in this field. [Copyright &y& Elsevier]

Abstract: This paper proposes a framework to analyze the interdisciplinary collaboration in a coauthorship network from a meso perspective using topic modeling: (1) a customized topic model is developed to capture and formalize the interdisciplinary feature; and (2) the two algorithms Diversity Subgraph Extraction (DSE) and Constraint-based Diversity Subgraph Extraction (CDSE) are designed and implemented to extract a meso view, i.e. a diversity subgraph of the interdisciplinary collaboration. The proposed framework is demonstrated using a coauthorship network in the field of computer science. A comparison between DSE and Breadth First Search (BSF)-based subgraph extraction favors DSE in capturing the diversity in interdisciplinary collaboration. Potential possibilities for studying various research topics based on the proposed framework of analysis are discussed. [Copyright &y& Elsevier]

Abstract: Imagine a situation in which you had to design a physical agent that could collect information from its environment, then store and process that information to help it respond appropriately to novel situations. What kinds of information should it attend to? How should the information be represented so as to allow efficient use and re-use? What kinds of constraints and trade-offs would there be? There are no unique answers. In this paper, we discuss some of the ways in which the need to be able to address problems of varying kinds and complexity can be met by different information processing systems. We also discuss different ways in which relevant information can be obtained, and how different kinds of information can be processed and used, by both biological organisms and artificial agents. We analyse several constraints and design features, and show how they relate both to biological organisms, and to lessons that can be learned from building artificial systems. Our standpoint overlaps with in that we assume that a collection of mechanisms geared to learning and developing in biological environments are available in forms that constrain, but do not determine, what can or will be learnt by individuals. [Copyright &y& Elsevier]

Abstract: Since the concept of IFS-probability was proposed, the probability theory for IF-events has been constructed. In this paper the concepts of IVFS-probability and IVIFS-probability are proposed for the first time. And the representation theorem for IVFS-probability is given. Furthermore, the relationships between IFS-probability, IVFS-probability and IVIFS-probability are discussed. [Copyright &y& Elsevier]

Abstract: In a planar geometric network vertices are located in the plane, and edges are straight line segments connecting pairs of vertices, such that no two of them intersect. In this paper we study distributed computing in asynchronous, failure-free planar geometric networks, where each vertex is associated to a processor, and each edge to a bidirectional message communication link. Processors are aware of their locations in the plane. We consider fundamental computational geometry problems from the distributed computing point of view, such as finding the convex hull of a geometric network and identification of the external face. We also study the classic distributed computing problem of leader election, to understand the impact that geometric information has on the message complexity of solving it. We obtain an message complexity algorithm to find the convex hull, and an message complexity algorithm to identify the external face of a geometric network of processors. We present a matching lower bound for the external face problem. We prove that the message complexity of leader election in a geometric ring is , hence geometric information does not help in reducing the message complexity of this problem. [Copyright &y& Elsevier]

Abstract: Radio-frequency identification (RFID) uses non-contact data access mechanism to read or write tag data through the radio frequency transmitted by the readers. Currently, the RFID systems are applied in different areas. However, the data access rate of a RFID system could be interfered by the environment furnishings, barriers, deployment method, and number of readers. The system stability heavily depends on the experiences of the deployment engineers especially for the active readers. This paper proposes an intelligent deployment system for RFID readers. The system uses the furnished simulation of environment and the best deployment of readers to construct an automatic deployment system for the RFID readers. The former constructs a fuzzy interference model of barriers according to the materials and inference degree of the furnishings. The latter uses the reader cluster and genetic algorithm to establish the best deployment plan of readers. The experimental results show that the system can reduce the interference problem of reader deployment as well as improve the reliability and stability of the RFID systems. [Copyright &y& Elsevier]

Abstract: Transfer learning aims to solve the problem that the training data from a source domain and the test data from a target domain follow different distributions. The feature-based method and the case-based method have been widely used in transfer learning. In this paper we propose a knowledge transfer method based on feature representation mapping from the source domain to the target domain. We first construct a new feature subspace, then build a feature representation mapping function and re-weight the source domain and the target domain data to minimize the distance between different distributions. As a result, with the new feature representations in this subspace, we can apply standard machine learning methods to train classifier models in the source domain for use in the target domain. Importantly, different from many previously proposed methods, we combine the feature-based method and the case-based method to construct the knowledge transfer model for solving text classification problems. The experimental results show that our algorithm greatly improves the classification performance over the traditional learning algorithms. [Copyright &y& Elsevier]

Abstract: Watermark is some imperceptible information embedded into the work for later verification and thus it can be used to prove the originality or to protect the work from being illegally copied or modified. proposed a muteness-based watermarking method for audio file. Their method can successfully embed watermarking information into audio file such that the human ears cannot distinguish the covered work from the original one. To improve the efficiency, we proposed a watermarking method for audio files in this paper. By adjusting the length of mute period dynamically, the proposed method can achieve the goal of watermark embedding with little variation of the original work. Experiment has shown that our method has the advantages of efficiency and fidelity as compared with theirs. Furthermore, it does not require the original audio file to derive the embedded watermark. [Copyright &y& Elsevier]

Abstract: Data mining is the process of extracting desirable knowledge or interesting patterns from existing databases for specific purposes. Recently, the fuzzy and the object concepts have been very popular and used in a variety of applications, especially for complex data description. This paper thus proposes a new fuzzy data-mining algorithm for extracting interesting knowledge from quantitative transactions stored as object data. Each item itself is thought of as a class, and each item purchased in a transaction is thought of as an instance. Instances with the same class (item name) may have different quantitative attribute values since they may appear in different transactions. The proposed fuzzy algorithm can be divided into two main phases. The first phase is called the fuzzy intra-object mining phase, in which the linguistic large itemsets associated with the same classes (items) but with different attributes are derived. Each linguistic large itemset found in this phase is thought of as a composite item used in phase 2. The second phase is called the fuzzy inter-object mining phase, in which the large itemsets are derived and used to represent the relationship among different kinds of objects. An example is used to illustrate the algorithm. Experimental results are also given to show the effects of the proposed algorithm. [Copyright &y& Elsevier]

Abstract: In this paper, we present a new method for analyzing fuzzy risk based on a new method for ranking generalized fuzzy numbers. First, we present a new method for ranking generalized fuzzy numbers. It considers the areas on the positive side, the areas on the negative side and the heights of the generalized fuzzy numbers to evaluate ranking scores of the generalized fuzzy numbers. The proposed method can overcome the drawbacks of some existing methods for ranking generalized fuzzy numbers. Then, we apply the proposed method for ranking generalized fuzzy numbers to develop a new method for dealing with fuzzy risk analysis problems. The proposed method provides us with a useful way to deal with fuzzy risk analysis problems based on generalized fuzzy numbers. [ABSTRACT FROM AUTHOR]

Abstract: Text steam analysis is now of great importance and practical value today. It has several applications such as news group filtering, topic detection & tracking (TDT), user characterized recommendation etc. Clustering is one of the most important methods of analyzing text stream. However, most text stream clustering algorithms rarely consider the possible change of features during a long-time of clustering, which is usually the case, leading to unsatisfactory results of the clustering system. The paper mainly focuses on the problem of adaptive feature selection for clustering text stream. A validity index based method of adaptive feature selection is proposed, incorporating with which a new text stream clustering algorithm is developed. During the clustering process, threshold of cluster valid index is used to automatically trigger feature re-selection in order to ensure the validity of clustering. The experiment using Reuters-21578 text set as the text source shows that the clustering algorithm reaches reasonable results of high quality. [ABSTRACT FROM AUTHOR]

Abstract: An ontology is a formal conceptualization of a domain, specifying the concepts of the domain and the relations between them. It is however not a straight forward task to use this knowledge for information retrieval purposes. In this paper we describe the concept of an ontological profile, which is a semantic extension of an ontology where each ontology concept is given a description in terms of a vector of weighted keywords. An experiment has been conducted with a prototype search engine using ontological profiles for query expansion. The evaluation shows encouraging results compared to standard keyword based search. Furthermore, we describe the notion of context in an information retrieval setting and address how we can combine semantics and context in search based on query expansion. [Copyright &y& Elsevier]

Abstract: The structure of approximability classes by the introduction of approximation preserving reductions has been one of the main research programmes in theoretical computer science during the last thirty years. This paper surveys the main results achieved in this domain. [Copyright &y& Elsevier]

Abstract: In this paper, we present a generalized model for handling prioritized multicriteria decision making systems. First, we present a new method for handling prioritized multicriteria decision making problems, where the weights of the lower priority criteria of each alternative depend on whether each alternative satisfies the requirements of all the higher priority criteria or not. Then, we also present a generalized prioritized multicriteria decision making method for handling multicriteria decision making problems, where some criteria may have equal priority which can be aggregated by the ordered weighted averaging (OWA) operator or the weighted averaging method. The proposed methods can overcome the drawbacks of the methods presented in [Yager, R. R. (2004a). Modeling prioritized multicriteria decision making. IEEE Transactions on Systems, Man, and Cybernetics-Part B: Cybernetics, 34(6), 2396–2404]. The proposed methods can handle multicriteria decision making problems in a more intelligent and more flexible manner. [Copyright &y& Elsevier]

Abstract: It has been a decade since a tripod model of pharmacognosy – organism, biological activity, chemical structure – was proposed. Since then advances in all disciplines have taken science into the 21st century. What are the implications for pharmacognosy? In this paper we expand the previous model, adding a new module with focus on informatics to encompass results of new technical and theoretical advancements for drug discovery. [Copyright &y& Elsevier]

Abstract: A two-dimensional word is a function on with finite number of values. The main problem we are interested in is the periodicity of two-dimensional words satisfying some local conditions. In this paper we prove that every bounded centered function on the infinite rectangular grid is periodic. A function is called centered if the sum of its values in every ball is equal to 0. Similar results are obtained for the infinite triangular and hexagonal grids. [Copyright &y& Elsevier]

Abstract: Let be an arbitrary submonoid of the free monoid , and let be a variable length code (for short a code). is weakly -complete iff any word in is a factor of some word in [J. Néraud, C. Selmi, Free monoid theory: Maximality and completeness in arbitrary submonoids, Internat. J. Algebra Comput. 13 (5) (2003) 507–516]. Given a regular submonoid , and given an arbitrary code , we are interested in the existence of a weakly -complete code that contains . Actually, in [J. Néraud, Completing a code in a regular submonoid, in: Acts of MCU’2004, Lect. Notes Comput. Sci. 3354 (2005) 281–291; J. Néraud, Completing a code in a submonoid of finite rank, Fund. Inform. 74 (2006) 549–562], by presenting a general formula, we have established that, in any case, such a code exists. In the present paper, we prove that any regular circular code may be embedded into a weakly -complete one iff the minimal automaton with behavior has a synchronizing word. As a consequence of our result an extension of the famous theorem of Schützenberger is stated for regular circular codes in the framework of regular submonoids. We study also the behaviour of the subclass of uniformly synchronous codes in connection with these questions. [Copyright &y& Elsevier]

Abstract: The technique of determining a generating function for an unambiguous context-free language is known as the Schützenberger methodology. For regular languages, Elena Barcucci et al. proposed an approach for inverting this methodology based on Soittola’s theorem. This idea allows a combinatorial interpretation (by means of a regular language) of certain positive integer sequences that are defined by C-finite recurrences. In this paper we present a Maple implementation of this inverse methodology and describe various applications. We give a short introduction to the underlying theory, i.e., the question of deciding -rationality. In addition, some aspects and problems concerning the implementation are discussed; some examples from combinatorics illustrate its applicability. [Copyright &y& Elsevier]

Abstract: To any infinite word over a finite alphabet we can associate two infinite words and such that any prefix of (resp. ) is the lexicographically smallest (resp. greatest) amongst the factors of of the same length. We say that an infinite word over is fine if there exists an infinite word such that, for any lexicographic order, where . In this paper, we characterize fine words; specifically, we prove that an infinite word is fine if and only if is either a strict episturmian word or a strict “skew episturmian word”. This characterization generalizes a recent result of G. Pirillo, who proved that a fine word over a 2-letter alphabet is either an (aperiodic) Sturmian word, or an ultimately periodic (but not periodic) infinite word, all of whose factors are (finite) Sturmian. [Copyright &y& Elsevier]

Abstract: In this paper we consider several questions related to the defect theorem for sets of three and four words. We start by investigating how large systems of pairwise independent or pairwise non-equivalent equations over three unknowns possessing purely non-periodic solutions can be. In other words, we analyze how weak the cumulative defect effect of such systems is. Then, we investigate the maximal size of chains of equations over three or four words such that every time we add a new equation the set of solutions strictly decreases. [Copyright &y& Elsevier]