Showing papers in "Journal of Universal Computer Science in 2006"

Plagiarism - A Survey

Abstract: Plagiarism in the sense of "theft of intellectual property" has been around for as long as humans have produced work of art and research. However, easy access to the Web, large databases, and telecommunication in general, has turned plagiarism into a serious problem for publishers, researchers and educational institutions. In this paper, we concentrate on textual plagiarism (as opposed to plagiarism in music, paintings, pictures, maps, technical drawings, etc.). We first discuss the complex general setting, then report on some results of plagiarism detection software and finally draw attention to the fact that any serious investigation in plagiarism turns up rather unexpected side-effects. We believe that this paper is of value to all researchers, educators and students and should be considered as seminal work that hopefully will encourage many still deeper investigations.

The Transformation of the Web: How Emerging Communities Shape the Information we Consume

Abstract: To date, one of the main aims of the World Wide Web has been to provide users with information. In addition to private homepages, large professional information providers, including news services, companies, and other organisations have set up web-sites. With the development and advance of recent technologies such as wikis, blogs, podcasting and file sharing this model is challenged and community-driven services are gaining influence rapidly. These new paradigms obliterate the clear distinction between information providers and consumers. The lines between producers and consumers are blurred even more by services such as Wikipedia, where every reader can become an author, instantly. This paper presents an overview of a broad selection of current technologies and services: blogs, wikis including Wikipedia and Wikinews, social networks such as Friendster and Orkut as well as related social services like del.icio.us, file sharing tools such as Flickr, and podcasting. These services enable user participation on the Web and manage to recruit a large number of users as authors of new content. It is argued that the transformations the Web is subject to are not driven by new technologies but by a fundamental mind shift that encourages individuals to take part in developing new structures and content. The evolving services and technologies encourage ordinary users to make their knowledge explicit and help a collective intelligence to develop.

Health Monitoring and Assistance to Support Aging in Place

Abstract: To many people, home is a sanctuary. For those people who need special medical care, they may need to be pulled out of their home to meet their medical needs. As the population ages, the percentage of people in this group is increasing and the effects are expensive as well as unsatisfying. We hypothesize that many people with disabilities can lead independent lives in their own homes with the aid of at- home automated assistance and health monitoring. In order to accomplish this, robust methods must be developed to collect relevant data and process it dynamically and adaptively to detect and/or predict threatening long-term trends or immediate crises. The main objective of this paper is to investigate techniques for using agent-based smart home technologies to provide this at-home health monitoring and assistance. To this end, we have developed novel inhabitant modeling and automation algorithms that provide remote health monitoring for caregivers. Specifically, we address the following technological challenges: 1) identifying lifestyle trends, 2) detecting anomalies in current data, and 3) designing a reminder assistance system. Our solution approaches are being tested in simulation and with volunteers at the UTA's MavHome site, an agent-based smart home project.

A Modular Architecture for Nodes in Wireless Sensor Networks

Abstract: The growth of sensor networks during the last years is a fact and within this field, wireless sensor networks are growing particularly as there are many applications that demand the use of many nodes, even hundreds or thousands. More and more applications are emerging to solve several problems in data acquisition and control in different environments, taking advantage of this technology. In this context, hardware design of the sensor network node becomes critical to satisfy the hard constraints imposed by wireless sensor networks, like low power consumption, low size and low cost. Moreover, these nodes must be capable of sensing, processing and communicating physical parameters, becoming true smart sensors in a network. With this goal in mind, we propose a modular architecture for the nodes, composed of four layers: communication, processing, power supply and sensing. The purpose is to minimize the redesign effort as well as to make the node flexible and adaptable to many different applications. In a first prototype of the node, we present a node with a mixed design based on a microcontroller and an FPGA for the processing layer and Bluetooth technology for communications.

The Impact of Behavioral Monitoring Technology on the Provision of Health Care in the Home

Abstract: The lack of appropriate and accurate information on the ability of a frail individual to accomplish specific task oriented activities can place the individual at risk or result in the allocation of costly and unnecessary care. Although there have been previous attempts to use computer technology to obtain this information, they have proved to be costly and complex and therefore not widely used. However, a behavioral monitoring technology, based on smart-home and telemedicine applications, has been developed that obtains more accurate and timely information on the ability of frail individuals to accomplish specific tasks in their own residences than any other existing method. During a twelve month pilot study, this system has been used by care providers to assess the status of their clients, respond to immediate needs and alter overall care plans, thus resulting in better care and greater peace of mind for the individual.

Persian/Arabic Baffletext CAPTCHA.

Abstract: Nowadays, many daily human activities such as education, trade, talks, etc are done by using the Internet. In such things as registration on Internet web sites, hackers write programs to make automatic false registration that waste the resources of the web sites while it may also stop it from functioning. Therefore, human users should be distinguished from computer programs. To this end, this paper presents a method for distinction of Persian and Arabic-language users from computer programs based on Persian and Arabic texts. Our proposed algorithm is based on adding a background to the image of a meaningless Persian/Arabic randomly generated word. This method relies on the difficulty of automatic separation of background from Persian/Arabic writing, due to the presence of many diacritical dots and signs. In this method, the image of a random meaningless Persian or Arabic word is shown to the user and he is asked to type it. Considering that the presently available Persian and Arabic OCR programs cannot identify these words, the word can be identified only by a Persian or Arabic- language user. This method also can be used to prevent program attacks, resource waste and performance reduction. The proposed method has been implemented by the Java language. The generated words are tested, using ReadIris and Omnipage OCR systems. These OCR systems were unable to recognize these words.

Extension of CQL over Dynamic Databases

Abstract: CQL, Continuous Query Language is suitable for data stream queries. Sometimes it is better if the queries operate on relational databases and data streams simultaneously. The execution of a CQL query takes a long time (several hours, days or even more). It is not clear what kind of semantics is suitable for the user when the database is updated during the execution of a CQL query. In this paper we give a short description of CQL, a characterization of update-problems, and we offer possible suggestions for the semantic extension of CQL. After the expansion, the CQL would be suitable for solving much more practical problems. The parallel usage of continuous data streams and updatable databases would be settled.

Introducing the ITP Tool: a Tutorial

Abstract: We present a tutorial of the ITP tool, a rewriting-based theorem prover that can be used to prove inductive properties of membership equational specifications. We also introduce membership equational logic as a formal language particularly ad- equate for specifying and verifying semantic data structures, such as ordered lists, binary search trees, priority queues, and powerlists. The ITP tool is a Maude program that makes extensive use of the reflective capabilities of this system. In fact, rewriting- based proof simplification steps are directly executed by the powerful underlying Maude rewriting engine. The ITP tool is currently available as a web-based application that includes a module editor, a formula editor, and a command editor. These editors allow users to create and modify their specifications, to formalize properties about them, and to guide their proofs by filling and submitting web forms.

Visualization Services in a Conference Context: An Approach by RFID Technology

Abstract: Ambient Intelligent (AmI) vision is a new concept materialized by the Six Framework Program of the European Community. It involves three key technologies: Ubiquitous Computing, Ubiquitous Communications and Natural Interfaces. With the increase in context aware applications it is important to keep these technologies in mind. In this paper we present a context aware application in a conference site based on the identification process using RFID. Furthermore the highlights of this proposal are based on the "ws" concepts. Three environments are modelled applying the "who" to the "when" and "where" to reach the "what". In this sense certain services are offered to the conference attendees, some of which are characteristics of this technology and others are the result of a context aware application, the visualization services named "Mosaics of Information".

Information and Hybrid Architecture Model of the OCP Contextual Information Management System

Abstract: This paper describes OCP (Open Context Platform), a middleware which provides support for management of contextual information and merging of information from different sources. The host system is thus endowed with proactive capacities which, in turn, provide a certain environmental intelligence (8). The approach consists of a modelling of contextual information which is based on Semantic Web derived technologies and a description of the structured merging in the form of decision rules. The latter serve to classify situations of interest and subsequently to trigger off the relevant actions at each moment. Elsewhere, the underlying architecture in OCP is designed so that it can function both by centralizing all the contextual information from a central server and by distributing it among consumers and producers of this type of information.

A Multi-objective Genetic Approach to Mapping Problem on Network-on-Chip.

Abstract: Advances in technology now make it possible to integrate hundreds of cores (e.g. general or special purpose processors, embedded memories, application specific components, mixedsignal I/O cores) in a single silicon die. The large number of resources that have to communicate makes the use of interconnection systems based on shared buses inefficient. One way to solve the problem of on-chip communications is to use a Network-on-Chip (NoC)-based communication infrastructure. Such interconnection systems offer new degrees of freedom, exploration of which may reveal significant optimization possibilities: the possibility of arranging the computing and storage resources in an NoC, for example, has a great impact on various performance indexes. The paper addresses the problem of topological mapping of intellectual properties (IPs) on the tiles of a mesh-based NoC architecture. The aim is to obtain the Pareto mappings that maximize performance and minimize power dissipation. We propose a heuristic technique based on evolutionary computing to obtain an optimal approximation of the Pareto-optimal front in an efficient and accurate way. At the same time, two of the most widely-known approaches to mapping in mesh-based NoC architectures are extended in order to explore the mapping space in a multicriteria mode. The approaches are then evaluated and compared, in terms of both accuracy and efficiency, on a platform based on an event-driven trace-based simulator which makes it possible to take account of important dynamic effects that have a great impact on mapping. The evaluation performed on both synthesized traffic and real applications (an MPEG-4 codec) confirms the efficiency, accuracy and scalability of the proposed approach.

Operational/Interpretive Unfolding of Multi-adjoint Logic Programs

Abstract: Multi-adjoint logic programming represents a very recent, extremely flex- ible attempt for introducing fuzzy logic into logic programming. In this setting, the execution of a goal w.r.t. a given program is done in two separate phases. During the operational one, admissible steps are systematically applied in a similar way to classi- cal resolution steps in pure logic programming, thus returning a computed substitution together with an expression where all atoms have been exploited. This last expression is then interpreted under a given lattice during the so called interpretive phase, hence returning a value which represents the fuzzy component (truth degree) of the computed answer. On the other hand, unfolding is a well known transformation rule widely used in declar- ative programming for optimizing and specializing programs, among other applications. In essence, it is usually based on the application of operational steps on the body of program rules. The novelty of this paper consists in showing that this process can also be made in terms of interpretive steps. We present two strongly related kinds of unfolding (operational and interpretive), which, apart from exhibiting strong correct- ness properties (i.e. they preserve the semantics of computed substitutions and truth degrees) they are able to significantly simplify the two execution phases when solving goals.

Quality of Privacy (QoP) for the design of ubiquitous healthcare applications

Abstract: Privacy is a complex social process that will persist in one form or another as a fundamental feature of the substrate into which ubiquitous computing (ubicomp) is threaded. Hospitals are natural candidates for the deployment of ubicomp technology while at the same time face significant privacy requirements. To better understand the privacy issues related to the use of ubicomp we place our efforts in understanding the contextual information relevant to privacy and how its interplay shapes the perception of privacy in a hospital. The results indicate that hospital workers tend to manage privacy by assessing the value of the services provided by a ubicomp application and the amount of privacy they are willing to concede. For ubicomp applications to better deal with this issue we introduce the concept of Quality of Privacy (QoP) which allows balancing this trade-off in a similar way as that of Quality of Service (QoS) does for networking applications. We propose an architecture that allows designers to identify different levels of QoP based on the user's context. Finally, we identify the main privacy risks of a location-aware application and we extend its architecture exemplifying the use of QoP to manage those risks.

Sequential data assimilation: Information fusion of a numerical simulation and large scale observation data

Abstract: Data assimilation is a method of combining an imperfect simulation model and a number of incomplete observation data. Sequential data assimilation is a data assimilation in which simulation variables are corrected at every time step of observa- tion. The ensemble Kalman filter is developed for a sequential data assimilation and frequently used in geophysics. On the other hand, the particle filter developed and used in statistics is similar in view of ensemble-based method, but it has different properties. In this paper, these two ensemble based filters are compared and characterized through matrix representation. An application of sequential data assimilation to tsunami simu- lation model with a numerical experiment is also shown. The particle filter is employed for this application. An erroneous bottom topography is corrected in the numerical experiment, which demonstrates that the particle filter is useful tool as the sequential data assimilation method.

Pseudorandom Number Generation: Impossibility and Compromise

Abstract: Pseudorandom number generators are widely used in the area of simula- tion. Defective generators are still widely used in standard library programs, although better pseudorandom number generators such as the Mersenne Twister are freely avail- able. This manuscript gives a brief explanation on pseudorandom number generators for Monte Carlo simulation. The existing definitions of pseudorandomness are not sat- isfactorially practical, since the generation of sequences satisfying the definitions is sometimes impossible, somtimes rather slow. As a compromise, to design a fast and reliable generator, some mathematical indices are used as measures of pseudorandom- ness, such as the period and the higher-dimensional equidistribution property. There is no rigorous justification for the use of these indices as measures of pseudorandomness, but experiences show their usefulness in choosing pseudorandom number generators.

DS/CDMA Multiuser Detection with Evolutionary Algorithms

Abstract: This work analyses two heuristic algorithms based on the genetic evolution theory applied to direct sequence code division multiple access (DS/CDMA) com- munication systems. For different phases of an evolutionary algorithm new biological processes are analyzed, specially adapted to the multiuser detection (MuD) problem in multipath fading channels. Monte Carlo simulation results show that the detection based on evolutionary heuristic algorithms is a viable option when compared with the optimum solution (ML - maximum likelihood), even for hostile channel conditions and severe system operation. Additionally, a comparative table is presented considering the relation between bit error rate (BER) and complexity as the main analyzed figure of merit. Each algorithm complexity is determined and compared with others based on the required number of computational operations to reach de optimum performance and also the spent computational time.

Data Mining Methods for Discovering Interesting Exceptions from an Unsupervised Table

Abstract: In this paper, we survey efforts devoted to discovering interesting excep- tions from data in data mining. An exception differs from the rest of data and thus is interesting and can be a clue for further discoveries. We classify methods into exception instance discovery, exception rule discovery, and exception structured-rules discovery and give a condensed and comprehensive introduction.

Variations on Itai-Rodeh leader election for anonymous rings and their analysis in PRISM

Abstract: We present two probabilistic leader election algorithms for anonymous uni- directional rings with FIFO channels, based on an algorithm from Itai and Rodeh (Itai and Rodeh 1981). In contrast to the Itai-Rodeh algorithm, our algorithms are finite-state. So they can be analyzed using explicit state space exploration; we used the probabilistic model checker PRISM to verify, for rings up to size four, that even- tually a unique leader is elected with probability one. Furthermore, we give a manual correctness proof for each algorithm.

A Formal Architectural Description Language based on Symbolic Transition Systems and Modal Logic

Abstract: Component Based Software Engineering has now emerged as a discipline for system development. After years of battle between component platforms, the need for means to abstract away from specific implementation details is now recognized. This paves the way for model driven approaches (such as MDE) but also for the more older Architectural Description Language (ADL) paradigm. In this paper we present KADL, an ADL based on the Korrigan formal language which supports the following features: integration of fully formal behaviours and data types, expressive component composition mechanisms through the use of modal logic, specification readability through graphical notations, and dedicated architectural analysis techniques. Key Words: Architectural Description Language, Component Based Software Engineering, Mixed Formal Specifications, Symbolic Transition Systems, Abstract Data Types, Modal Logic Glue, Graphical Notations, Verification.

Why is Wikipedia so Successful? Experiences in Establishing the Principles in Higher Education

Abstract: Wikipedia [Wikipedia06] is a well known and very successful online-encyclopaedia. It is free, available in different languages and everybody is permitted to contribute. This results in a worldwide collaboration aiming at one target: Anybody can provide information for everybody. However, one interesting question would be whether this successful principle can be transferred to learning communities in higher education and how it could be achieved. This paper presents some experiences gained during the use of a Wiki-System during lectures on structural concrete at both the University of Applied Sciences FH Joanneum and Graz University of Technology. Our approach included a technical and didactical concept as well as accepted investigation methods. Presenting a full analysis of the implementation, this paper shows its general potential, the weakness of the principle and further future approaches.

EMI 2 lets: A reflective framework for enabling AmI

Abstract: An interesting new application domain for handheld devices may be represented by Ambient Intelligence (AmI), where they can be used as intermediaries between us and our surrounding environment. Thus, the devices, which always accompany us, will behave as electronic butlers who assist us in our daily tasks, by interacting with the smart objects (everyday objects augmented with computational services) in our whereabouts. In order to achieve such goal, this paper proposes an AmI-enabling framework providing two main functions: a) facilitate the development and deployment of smart objects and b) transform mobile devices into universal remote controllers of those smart objects.

Constraint Based Methods for Biological Sequence Analysis

Abstract: The need for processing biological information is rapidly growing, owing to the masses of new information in digital form being produced at this time. Old method- ologies for processing it can no longer keep up with this rate of growth. The methods of Artificial Intelligence (AI) in general and of language processing in particular can offer much towards solving this problem. However, interdisciplinary research between language processing and molecular biology is not yet widespread, partly because of the effort needed for each specialist to understand the other one's jargon. We argue that by looking at the problems of molecular biology from a language processing perspec- tive, and using constraint based logic methodologies we can shorten the gap and make interdisciplinary collaborations more effective. We shall discuss several sequence anal- ysis problems in terms of constraint based formalisms such Concept Formation Rules, Constraint Handling Rules (CHR) and their grammatical counterpart, CHRG. We pos- tulate that genetic structure analysis can also benefit from these methods, for instance to reconstruct from a given RNA secondary structure, a nucleotide sequence that folds into it. Our proposed methodologies lend direct executability to high level descriptions of the problems at hand and thus contribute to rapid while efficient prototyping.

A mechanism for solving conflicts in ambient intelligent environments

Abstract: Ambient Intelligence scenarios describe situations in which multitude of devices and agents live together. In this kind of scenarios is frequent to see the appearance of conflicts when modifying the state of a device as for example a lamp. Those problems are not as much of sharing of resources as of conflict of orders coming from different agents. This coexistence must deal also with the desire of privacy of the different users over their personal information such as where they are, what their preferences are or to whom this information should be available. When facing incompatible orders over the state of a device it turns necessary to make a decision. In this paper we propose a centralised mechanism based on prioritized FIFO queues to decide the order in which the control of a device is granted. The priority of the commands is calculated following a policy that considers issues such as the commander's role, command's type, context's state and commander-context and commander-resource relations. Finally we propose a set of particular policies for those resources that do not adjust to the general policy. In addition we present a model pretending to integrate privacy through limiting and protecting contextual information.

Reversible Karatsuba's Algorithm

Abstract: Karatsuba discovered the first algorithm that accomplishes multiprecision integer multiplication with complexity below that of the grade-school method. This al- gorithm is implemented nowadays in computer algebra systems using irreversible logic. In this paper we describe reversible circuits for the Karatsuba's algorithm and analyze their computational complexity. We discuss garbage disposal methods and compare with the well known Bennett's schemes. These circuits can be used in reversible com- puters which have the advantage of being very efficient in terms of energy consumption. The algorithm can also be used in quantum computers and is an improvement of pre- vious circuits for the same purpose described in the literature.

Restricting the view and connecting the dots: Dangers of a web search engine monopoly

Abstract: Everyone realizes how powerful the few big Web search engine companies have become, both in terms of financial resources due to soaring stock quotes and in terms of the still hidden value of the wealth of information available to them. Following the common belief that “information is power” the implications of what the data collection of a de-facto monopolist in the field like Google could be used for should be obvious. However, user studies show that the real implications of what a company like Google can do, is already ...

Course modeling for student profile based flexible higher education on the internet

Abstract: Higher education courses are increasingly created as student organized collections of interrelated modules. At the same time, frequent change of subject matter and knowledge in its background must be handled. Above and other factors created and recognized a need for efficient computer based course management. Conventional computer aided teaching methods are not suitable to organize, manage, and communicate the comprehensive course information any more. The authors considered an analogy with well- organized computer descriptions of interrelated objects in the form of comprehensive integrated models in product engineering. Modeling and management of information serve engineering activities during lifecycle of product. Relevant advanced characteristics of integrated product descriptions are process orientation, definition of application oriented building elements called as features, and assistance of decisions by knowledge representations. The authors considered higher education course as one kind of product and proposed a course model. They focused to integrating student, teacher, and institute demand driven characteristics of modeling. Model is developed for application by course procedures. While conventional virtual education systems concentrate to computer mediated distance education, the authors considered arbitrary mix of campus and distance styles of education. In this paper, the authors first give an introduction in their approach to classroom modeling by a comparison of conventional distance education, conventional virtual classroom, and the proposed model based virtual classroom. Next, functional elements of the proposed course modeling and components of virtual classroom are explained. Conflicts as consequences of inappropriate capability or breaking of human intent are analyzed. Following this, initial conditions for definition of course module and construction of course module using modification by features are detailed. Finally, future work for implementation of the modeling in an experimental system composed by professional product lifecycle management (PLM) system, configurable virtual teaching environment, its virtual classroom extension and virtual classroom extension to the engineering modeling system is concluded.

Multi-Objective Evolutionary Algorithms and Pattern Search Methods for Circuit Design Problems

Abstract: The paper concerns the design of evolutionary algorithms and pattern search methods on two circuit design problems: the multi-objective optimization of an Operational Transconductance Amplifier and of a fifth-order leapfrog filter. The experimental results obtained show that evolutionary algorithms are more robust and effective in terms of the quality of the solutions and computational effort than classical methods. In particular, the observed Pareto fronts determined by evolutionary algo- rithms has a better spread of solutions with a larger number of nondominated solutions when compared to the classical multi-objective techniques.

Ubiquitous computing and ambient intelligence: New challenges for computing

Abstract: The IST Advisory Group (ISTAG) of the European Union had a vision of \"Ambient Intelligence\" (AmI) in 1999. It refers to \" an exciting new paradigm of information technology, in which people are empowered through a digital environment that is aware of their presence and context sensitive, adaptive and responsive to their needs, habits, gestures and emotions \". In AmI the technology will become invisible, embedded, present whenever we need it, enabled by simple interactions, attuned to all our senses and adaptive to users and contexts (Scenarios for Ambient Intelligence). AmI proposes a shift in computing from the traditional computer to a whole set of devices placed around us providing users with an intelligent background. AmI involves three key technologies: Ubiquitous Computing integrating microprocessors into everyday objects; Ubiquitous Communication, which allows these objects to communicate with each other and with users; and finally, Natural Interfaces, which allows interacting with the environment in an easier and more personalized way. This special issue is aimed to join research efforts in these three technologies, although emphasis will be placed on the first one, which emerges directly from the seminal vision of Mark Weiser in the Xerox Lab. Nine papers have been selected to represent this area of research. The first one, \" Development of Ambient Intelligence Applications using Components and Aspects \" by Fuentes et al. focuses on applying aspect technologies to components in order to improve AmI application modularization. Their work presents the benefits of aspect technologies with regard to reusability and adaptability, by showing the limitations of a well-known component-based AmI middleware platform named PCOM. \" Quality of Privacy (QoP) for the Design of Ubiquitous Healthcare Applications \" by Tentori et al. describes a workplace study conducted in a hospital, aimed at understanding the privacy issues that hospital workers might face in a pervasive computing environment. From the results of the study the authors propose

A New System Dedicated to Real-time Cardiac Arrhythmias Tele-assistance and Monitoring

Abstract: More than 60,000 people die suddenly each year in France due to cardiac arrhythmias. The current techniques used to diagnose cardiac arrhythmias such as HOLTER, R.TEST and telemetry system are partially efficient owing to the limitation of the duration of monitoring. This paper presents a new system dedicated to real-time cardiac arrhythmias tele- assistance and monitoring. This system is generally composed of 4 main configurable elements: wireless ECG sensor, local access unit, remote centre server, and remote surveillance terminal. The main technical challenges of this system include three aspects: a real-time automatic ECG diagnostic algorithm, an embedded real-time multi-task operating system, and a real-time reliable telemedicine communication protocol. This paper gives our solutions to these problems and specifies the technical details. Currently, this system has been evaluated on thirty patients at the CHRU of Gabriel Montpied hospital (Clermont-Ferrand, France) and also been used to test the athletes' cardiac status during the physical exercises. The performance results show that this system meets fully the requirements of real-time cardiac monitoring and diagnosing application and can be used as a long-term cardiac healthcare equipment.

A Pervasive Multimodal Tele-Home Healthcare System

Abstract: This paper proposes a Human-centered Pervasive Computing System Model (HPC), a Layered Architectural Analysis and Design Method (LAAD) and a Waterfall Prototyping Process Model (WPP). Based on the HPC model and the LAAD method, a pervasive computing based multimodal tele-home healthcare system is designed and partly implemented using the Waterfall Prototyping Process. The design and implementation issues are discussed in more detail. Some testing results are presented.