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With the rapid development of embedded systems, battery life becomes a critical restriction factor. Dynamic voltage scaling (DVS) has been proven to be an effective method for reducing energy consumption of processors. This paper proposes an energy-saving algorithm under a task model (the MSPR model) where a task consists of multiple subtasks with different fixed priorities. This algorithm includes two parts. The first part is a static algorithm, which exploits the relationship among tasks to set the slowdown factors of subtasks. The second part is an algorithm that dynamically reclaims and reuses the slack time of precedent subtasks during the execution of tasks. To the best of our knowledge, this is the first work for energy-efficient scheduling under the complex periodic real-time task model where a task consists of multiple subtasks with different fixed priorities. Experimental results show this method can reduce energy consumption by 20%-80%, while guaranteeing the real-time requirements of systems. [ABSTRACT FROM AUTHOR]

In this paper, we study the problem of scheduling a set of n periodic preemptive independent hard real-time tasks on the minimum number of processors. We assume that the partitioning strategy is used to allocate the tasks to the processors and the EDF method is used to schedule the tasks on each processor. It is known that this scenario is NP-hard; thus, it is unlikely to find a polynomial time algorithm to schedule the tasks on the minimum number of processors. In this work, we derive a lower and an upper bound for the number of processors required to satisfy the constraints of our problem. We also compare a number of heuristic algorithms with each other and with the bounds derived in this paper. Numerical results demonstrate that our lower bound is very tight and it is very close to the optimal solution. [ABSTRACT FROM AUTHOR]

Efficient management of service level agreements which govern provision of service compositions remains a big challenge in the Web services environment. This paper reports innovative research aiming at supporting autonomous establishment of a set of interrelated service level agreements for service compositions. In this paper, an agent-based framework is proposed to exploit agent interaction and negotiation capabilities for achieving agreements on service provision. Based on this framework, this paper also discusses mechanisms for agents representing service consumers and providers to negotiate quality of service constraints for constituent services in a coordinated way, with a focus on achieving end-to-end quality of service requirements. [ABSTRACT FROM AUTHOR]

The interactive digital multimedia broadcasting stands for a convergence application between digital multimedia broadcasting service and wireless internet service. It develops MPEG-4 BIFS (Binary Format for Scene) technologies which is standard component of associated data service for DMB. In this paper, we propose system architecture of the interactive DMB, called the interaction manager. The interactive DMB facilitates to transmit interactive contents and user can easily use these contents by clicking or typing some additional information. The proposed interactive DMB system can capture and response user interaction information by using the return channel. In this paper, we are mainly focused on extracting the event data of the user interaction on the device. We suggest an analyzer to catch the user event and transform into a specific format for bidirectional DMB service system. [ABSTRACT FROM AUTHOR]

Pattern matching is one of the most performance critical components in network intrusion detection and prevention system, which needs to be accelerated by carefully designed architectures. In this paper, we present a highly parameterized multilevel pattern matching architecture (MPM), which is implemented on FPGA by exploiting redundant resources among patterns for less chip area. In practice, MPM can be partitioned to several pipelines for high frequency. This paper also presents a pattern set compiler that can generate RTL codes of MPM with the given pattern set and predefined parameters. One MPM architecture is generated by our compiler based on Snort rules on Xilinx FPGA. The results show that MPM can achieve 4.3Gbps throughput with only 0.22 slices per character, about one half chip area than the most area-efficient architecture in literature. MPM can be parameterized potential for more than 100 Gbps throughput. [ABSTRACT FROM AUTHOR]

This paper describes a metamodeling strategy of Service Level Agreements for Digital Video Broadcasting services based on Service Level Agreement Language(SLAng). The purpose of the paper is to provide a detailed analysis of SLAs in this domain and provide a motivation for modeling and automating their management. We also discuss why precise and machine readable SLAs can improve the levels of automation in SLA Management thereby reducing potential violations. The meta-modeling approach based on the Model Driven Architecture(MDA) described in this paper also simplifies the integration of a SLA Management systems with other infrastructure that delivers the service to the client. [ABSTRACT FROM AUTHOR]

We demonstrate in the paper that user movement has great influences on the system performance of mobile cellular networks. We also develop a system model to study to what extent the influences will be, with focusing on the user movement simulation. We concern the parameters that determine the system performance of mobile cellular networks. We show partially in this paper that these parameters vary while user movement changes, but the effects are interactive. Since handoff calls are given a higher priority over new calls and GC mechanism is employed, our analysis shows that a mature mobile cellular network should make use of user movement characteristics and dynamically adjust its reservation threshold of the handoff call requests. Extensive simulation results validate our analysis. [ABSTRACT FROM AUTHOR]

Recently, information communication market is reorganized focused on the digital convergence service used for integrating the communication, broadcasting and internet media by connecting the communication equipment, broadcasting equipment and computer via a network. The mobility support protocol enabling the effective handover between heterogeneous networks is emerged as the hot issue in relation with these next generation communication networks. In this paper, we are to suggest the MIH Vertical handover procedure required for the implementation of MIH over MIPv4 Low-Latency vertical handover by analyzing the handover performance in the overlap area between wireless networks using the vertical handover function of MIPv4 Mobile IP Technology of IETF and considering the expected problems. Also, we are to suggest the MIH L2-Trigger generation algorithm required for deciding the optimal handoff. We evaluate the vertical handover performance of MIPv4 low-latency in the overlap area between wireless networks by using the NS-2 and applying the IEEE 802.21 MIH (Media Independent Handover) based on the suggested technique and algorithm. [ABSTRACT FROM AUTHOR]

Architecting service-oriented systems is a complex design activity. It involves making trade-offs among a number of interdependent design decisions, which are drawn from a range of concerns by various software stakeholders. In order to achieve effective and efficient SOC design we believe a careful study of architectural styles that can form the reference architecture is important. Hence, this paper provides a study of architectural styles for the reference architecture of SOC-based software systems. We propose a classification scheme for the architecture styles. These architectural styles are extracted from existing research projects and industry practices based on our classification scheme. For all those identified styles, we present an evolution trend driven by engineering principles for Internet-scale systems. As a result, this paper moves the first step towards creating a Reference Architecture that can be utilised to provide sensible guidance on the design of Web services application architecture. [ABSTRACT FROM AUTHOR]

How to discover resource rapidly and exactly in distributed and heterogeneous grid environment is a key problem that affects grid computing performance. In this paper, the P2P method is used to improve scalability of resource discovery mechanism, and a decentralized resource discovery method with well scalability is presented, this method uses binary tree to manage data, each node in grid is responsible for managing a part of resource information. Experimental result shows that the method presented in this paper can resolve many problems that exist in centralized mechanism, such as poor scalability, heavy load on resource information server and single point failure. [ABSTRACT FROM AUTHOR]

The paper describes a transformational approach for the specification and formal verification of concurrent and real-time systems.At upper level, one system is specified using the timed process algebra RT-LOTOS. The output of the proposed transformation is a Time Petri net (TPN). The paper particularly shows how a TPN can be automatically constructed from an RT-LOTOS specification using a compositionally defined mapping. The proof of the translation consistency is sketched in the paper and developed in[1]. The RT-LOTOS to TPN translation patterns formalized in the paper are being implemented. in a prototype tool. This enables reusing TPNs verification techniques and tools for the profit of RT-LOTOS. [ABSTRACT FROM AUTHOR]

CE-ants (Cross Entropy ants) is a distributed, robust and adaptive swarm intelligence system for dealing with path management in communication networks. This paper focuses on strategies for adjusting the overhead generated by the CE-ants as the state of the network changes. The overhead is in terms of number of management packets (ants) generated, and the adjustments are done by controlling the generation rate of ants traversing the network. The self-tuned strategies proposed in this paper detect state changes implicitly by monitoring parameters and ant rates in the management system. Rate adaptation is done both in the network nodes and in the peering points of the virtual paths. The results are promising, and compared to fixed rate strategies the self-tuned strategies show a significant saving (70-85%) in number of packets, and has similar (even slightly better) data packet delay and service availability. The rate adaptation in network nodes provides fast restoration with short path detection times and hence also high service availability. The implicit self-tuned ant rate in the path endpoints improves the convergence time on link state events without flooding the network with management packets in steady state when these are not required. Keywords: Cross Entropy, swarm intelligence, CE-ants, network management, restoration time, service availability. [ABSTRACT FROM AUTHOR]

This paper ascribes a formal semantics to advice weaving in AspectJ. Since the version 1.1, AspectJ language is developed using bytecode weaving, which combines aspects and classes to produce ".class" files that run in a Java Virtual Machine (JVM). In AspectJ, advice weaving is done statically by inserting the advice functionality in some regions of the code. These regions are join points that are declared using pointcuts. In this paper, we focus only on static pointcuts, i.e., pointcuts that correspond directly to locations in the bytecode. AspectJ dynamic pointcuts such as target, this, and cflow are not in the focus of this paper. [ABSTRACT FROM AUTHOR]

This paper discusses a prototype desktop ambient display system known as the Ambient Workplace (AW) that is used to visualise some aspects of cooperation among a group of co-workers. The AW draws on the ambient technology paradigm by providing a visualisation that represents the interactions of the co-workers (either individuals or groups) in their peripheral attention zone. The paper discusses the development of a prototype system based on a series of indices and uses a maritime flags metaphor. The paper also presents some early results from a user study. [ABSTRACT FROM AUTHOR]

Software product families have found broad adoption in the embedded systems industry. Product family thinking has been prevalent in this context for mechanics and hardware and adopting the same for software has been viewed as a logical approach. During recent years, however, the trends of convergence, end-to-end solutions, shortened innovation and R&D cycles and differentiation through software engineering capabilities have lead to a development where organizations are stretching the scope of their product families far beyond the initial design. Failing to adjust the product family approach, including the architectural and process dimensions when the business strategy is changing is leading to several challenging problems that can be viewed as symptoms of this approach. This paper discusses the key symptoms, the underlying causes for these symptoms as well as solutions for realigning the product family approach with the business strategy. [ABSTRACT FROM AUTHOR]

This paper presents a framework for deploying software components over a distributed system by using the notion of dynamics between components. It enables an application to be composed of one or more mobile components that can be deployed to different computers when the application is being executed. The key idea behind the framework is to provide components with deployment policies corresponding to gravitational and repulsive forces. The polices control the relocation relation between two components. As a result, a federation of distributed components can be moved and changed over a distributed system in a self-organizing manner. This paper also presents a prototype implementation of the approach and its applications. [ABSTRACT FROM AUTHOR]

This paper addresses personalised cooperative mobile learning. Context, context-awareness and the application of context-awareness are considered. The development of a generic RDF context framework is presented, adaptability is considered and comparisons are drawn with related research. Context definitions are domain specific with each domain requiring specific contextual design. In this paper, the focus is the context definition for a student in the domain of higher education. A context reasoning ontology is introduced to provide support for intelligent context processing. The paper concludes that RDF/RDFS combined with OWL and Jena provides a basis for the creation of context, context reasoning with ontology enabling effective intelligent context processing. [ABSTRACT FROM AUTHOR]

E-learning has been adopted by more and more educational institutions to implement their new learning and teaching strategy around the world. Students can study their courses which could be run by different universities which run different e-learning platforms. A universal data integrated e-learning platform is essential to transparentise the significant difference among disparate data sources which are used by different e-learning systems. This paper proposes an effective data integration mechanism for e-learning system. At the same time security concerns are discussed. The workflow-based data integration approach is shown in this paper. [ABSTRACT FROM AUTHOR]

Context technology is a core component in cooperative mobile applications. Based on our research project "A Context Framework for Personalised Mobile Learning in Pedagogic Systems", this paper presents a semantic context model called "SmartContext", which includes a standardised context template, a context reasoning ontology and a context middleware to investigate a solution for supporting cooperative mobile learning. The integration of "SmartContext" with the current e-learning system in University of Central England is also included in this paper. [ABSTRACT FROM AUTHOR]

This paper presents an approach of multidisciplinary knowledge modeling for concurrent and collaborative design. Firstly, a method to acquire the knowledge from simulation and specification is studied. The knowledge is used to constitute concurrent and collaborative design model. Secondly, a concurrent and collaborative design algorithm is presented to solve the model. Finally, the method is demonstrated by a design example of bogie. The results prove that multidisciplinary knowledge modeling from simulation data and specification is feasible, and the proposed method can be applied in concurrent and collaborative design process. [ABSTRACT FROM AUTHOR]

This paper describes the extended quality function deployment (QFD) in life cycle design (LCD) based on the traditional QFD which is often used at the requirement analysis stage. By investigating QFD in the product life cycle design, the extended QFD is proposed with the theoretical frame. The extension begins with the analysis of requirement by adding environment and cost factors, instead of only customer requirements, as the input of the 1st level house of quality (HoQ). Accordingly, multi-target values are built in. In a sequential process of the LCD, the extension carries out requirement deployment, function deployment, equipment deployment, part deployment, cost deployment and reliability deployment. Finally, this paper reveals how to apply the extended QFD in LCD and how to choose and adjust HoQ for different products. [ABSTRACT FROM AUTHOR]

This paper presents an application framework for constructing sketch-based cooperative design (especially for distributed conceptual design) tools. Three key issues are addressed: (1) how to represent and store sketch document; (2) how does the system infer the designers' intention and help them to complete the design process; (3) how to implement the communication between the client and the server. Solutions to these problems are proposed in this paper. The framework has been implemented and tested on a variety of applications, for example, cooperative UML diagram design. The primary experiments demonstrate the efficiency of the proposed framework. [ABSTRACT FROM AUTHOR]

It is difficult to manage constraint information in cooperative design due to its variety and changeability. The concept of Constraint Information Visualization (CIV) in cooperative design and CIV framework comprising the CIV methodology are put forward to control cooperative design flow efficiently, detect constraint conflicts early and negotiate the contradiction under the support of visualization. On the basis of classification and representation of constraint information, this paper discusses the importance of CIV and its formalized description for cooperative design. The procedure of visual mapping and harmony evaluation is given in details. The main step of visual mapping is divided into classification mapping, structure and harmony mapping and detailed property mapping. Visual Mapping implements mapping from constraint information to visual representation with corresponding mapping modes. The concepts of local harmony and global harmony are also proposed for cooperation. An application of CIV verifies CIV methodology, which will direct a new way to implement complicated constraints management in cooperative design. [ABSTRACT FROM AUTHOR]

Hierarchical Mobile IPv6 (HMIPv6) has been proposed to accommodate frequent mobility of an MN and reduce the signaling load in the Internet. In this paper, we propose hierarchical management scheme for Mobile IPv6 where MAP (Mobility Anchor Point) has priority queues for faster processing location update procedure in HMIPv6 system. The performance analysis and the numerical results presented in this paper show that our proposal has superior performance to the hierarchical Mobile IPv6. [ABSTRACT FROM AUTHOR]

WSNs (Wireless Sensor Network) can employ a burst technique known as 802.11e TXOP (Transmission Opportunity) operation to send sensor data backlogged during the sleep period [1] and FEC (Forward Error Correction) techniques to resist against their high BER (Bit Error Rate) [2]. This paper extends the 802.11e evaluation model [3], [4] to accurately calculate the performance of two TXOP schemes such as BI (Basic Immediate ACK) and BB (Basic Block ACK) with FEC codes. The generalized model accounts for the effect of propagation errors negligible in wireless LANs, the impact of HOB (Head-Of-Block) collision, and the effect of adopting FEC codes. This paper evaluates this extended model over real WSN channels abstracted by Gilbert model. The numerical calculations over real WSN traces confirm that the inclusion of HOB collisions causes the throughput difference of BB by up-to 194% comparing to [3]. They also predicts a trade-off between the performance improvement and the overhead of FEC codes over WSN channels. [ABSTRACT FROM AUTHOR]

In this paper, a fault-tolerant control method is presented with an application to steer-by-wire (SBW) system. SBW is a network-based vehicle steering system in which the mechanical linkage and hydraulics are replaced by electrical motors and fieldbus networks. Since failure of a steering system may result in a catastrophic accident, SBW can be considered as a safety-critical embedded system for which very high level of dependability must be satisfied. This paper proposes an effective control strategy to tolerate faulty actuators. The proposed method has a simple structure to be implemented on low cost embedded processors. The reconfiguration strategy consists of two fold: i) a smart actuator of which embedded microprocessor provides the fast and accurate diagnostic information through a time-triggered fieldbus, and ii) an IMC-PID controller which is capable of tolerating the effect of faults based on the diagnostic information being sent from the smart actuator. Simulation results with a SBW model show that the proposed method can enhance the system dependability in the presence of faults without using any redundant actuators. [ABSTRACT FROM AUTHOR]

Recent research on embedded real-time systems has focused on dynamic power management for fault-tolerance or dependability. In this paper, we provide an adaptive checkpointing scheme for fixed priority-based DVS scheduling in dependable real-time systems. Since there are some trade-offs in selection of dynamic processor scaling in terms of energy consumption and task reliability, we provide an adaptive energy-aware scaling assignment scheme with the feasibility test for fixed-priority scheduling with checkpointing. In the provided scheme, we analyze the number of tolerable faults of a task and the optimal checkpointing interval in order to meet the deadline and guarantee its specified reliability. The feasibility analysis of the fixed priority-based scheduling algorithm in dependable real-time systems is provided as well. [ABSTRACT FROM AUTHOR]

In this paper, we consider a new packet scheduling algorithm for real time traffic in the high speed downlink packet access system that has been introduced for WCDMA system to providing high transmission rates. The objective of the design is to meet the maximum tolerable delay and consider the channel assigning based on the received SIR for real-time traffic users. The proposed scheduling algorithm shows that the users are ranked by the ratios of the bits in the buffer to the residual time for transmission, the ranked users are assigned channels based on the SIR value table and get service one by one. The simulation results show that the proposed algorithm can provide the lower packet drop rate for real time quality of service (QoS) requirement. [ABSTRACT FROM AUTHOR]

In recent years, fieldbuses have been more widely used in real-time distributed control systems. There are many international fieldbus protocol standards, but they are not interoperable among themselves. This paper proposes an integrated fieldbus network architecture based on a switched Ethernet which provides real-time communication features to the nodes in different fieldbuses. This paper also analyzes the schedulability conditions for real-time periodic messages on the switched Ethernet and an EDF (Earliest Deadline First)-based scheduling algorithm to support the real-time communication requirements of the periodic messages without any change in the principles of the switch. [ABSTRACT FROM AUTHOR]

Recently, the continuously growing capacity of FPGAs has enabled us to place floating-point arithmetic IPs on FPGAs. The required area for floating-point computations, however, is still high. This paper presents a case study on behavioral synthesis of double-precision floating-point adders and adder/subtracters for FPGAs. With function-level transformations, we design totally 15 adders and 21 adder/subtracters from addition and subtraction functions written in C. Our experimental results show that the circuit area is reduced by 58%, the execution time is shortened by 47% and the area-delay product is improved by 69%. Through the case study, we show the effectiveness of behavioral synthesis with function-level transformations for designing complex arithmetic circuits. [ABSTRACT FROM AUTHOR]

In this paper we describe a self-organising and self-managing system for a Cooperative Service Provisioning (CSP) of media transport and processing services. The term cooperative is used since we assume that CSP providers as well as users offer resources to be utilised for media delivery and processing based on an Overlay Network principle. The core building block of the proposed system is a Distributed Hash Table extended with a CSP specific indexing principle and recursive search algorithm. The task of QoS constraint verification for a requested service is distributed between participating nodes. In this paper we describe CSP based on a Content Addressable Network (CAN) [1] DHT. The resulting system is evaluated based on a theoretical analysis as well as simulations. [ABSTRACT FROM AUTHOR]

This paper proposes a strategy to determine how much a given network can affect the QoS parameters of another, by interference. In order to achieve this, a measurement campaign was carried out in two stages: firstly with a single AP and later with two APs separated by a distance less than three meters, using the same channel. After the measurement, an analysis of the results and a set of inferences were made by using Bayesian Networks, whose inputs were the experimental data, i.e. QoS metrics such as: throughput, jitter, packet loss, PMOS and physical metrics like power and distance. [ABSTRACT FROM AUTHOR]

The rVsAll rollback-recovery protocol assures that consistency models, called session guarantees, are provided for mobile clients and unreliable servers. The protocol is optimized according to the required consistency model by taking into account properties of session guarantees and integrating their consistency management with known rollback-recovery techniques: message-logging and checkpointing. We have proved the correctness of rVsAll protocol in terms of safety and liveness properties. These properties assert that clients access object replicas maintained by servers according to the required session guarantee regardless of server's failures, and state that each access operation issued by clients will eventually be performed (in a finite time), even in the presence of server's failures. In this paper, we show that the proposed protocol is also optimal, in the sense that, the consistent global checkpoint taken in rVsAll protocol contains the minimal number of operations indispensable to fulfill the required session guarantees after server's failure and its recovery. The paper presents the proof of the optimality property of the proposed protocol. [ABSTRACT FROM AUTHOR]

Network-on-Chip is an alternative paradigm to improve communication bandwidth compared to bus-based communication, and its performance degrades if there is no effective flow control method., Heterogeneous networks with very slow processing elements (PEs) especially need a flow control mechanism at the transport layer to prevent too much packet injection. In this paper, a credit-based end-to-end flow control (CB-EEFC) is implemented to control the network latency at high traffic loads. Simulation in mesh networks shows improved performance in latency and 0.5% up to 3% saturated throughput decrease with the CB-EEFC method. RTL gate level simulation shows that a network interface using CB-EEFC brings about a 31.4% increase in complexity compared to a network interface without CB-EEFC. [ABSTRACT FROM AUTHOR]

This paper focuses on parallel interactive applications ranging from scientific visualization, to virtual reality or computational steering. Interactivity makes them particular on three main aspects: they are endlessly iterative, use advanced I/O devices, and must perform under strong performance constraints (latency, refresh rate). In this paper, we propose an application description language based on a data flow and hierarchical component model to cope with the complexity of parallel interactive applications. It enables us to define highly generic components, enforcing the application maintainability and portability. An implementation on top of the FlowVR middleware is presented. [ABSTRACT FROM AUTHOR]

In this paper a high performance storage system for RDF documents is introduced. The system employs optimized index structures for RDF data and efficient RDF query evaluation. The index scheme consists of 3 types of indices. Triple index manages basic RDF triples by dividing original RDF graph into several sub-graphs. Path index manages frequent RDF path patterns for long path query performance enhancement. Context index is optional for context oriented RDF data and temporal RDF data. In this paper, we describe the organization of index structures, show the process of evaluating queries based on the index structures, and provide a performance comparison with exist RDF databases through several benchmark experiments. [ABSTRACT FROM AUTHOR]

To fulfill the application of wireless network in small area, this paper proposed a protocol for decentralized all-connected wireless network. This protocol is based on DS-CDMA with the ability of multi-user detection (MUD). And it has the characteristics of transmitting data in parallel, high network throughput and low communication error rate. In this paper, the process of the protocol is introduced, and an improved quasi-synchronous decorrelation multi-user detection algorithm is deduced in detail. And then, the protocol is simulated and the results are analyzed. [ABSTRACT FROM AUTHOR]

Multi-log2N networks architecture is attractive for constructing optical switches, and the related routing algorithms are critical for the operation and efficiency of such switches. Although several routing algorithms have been proposed for multi-log2N networks, a full performance comparison among them is not available by now. Thus, this paper is committed to such a comparison in terms of blocking probability, time complexity, hardware cost and load balancing capability. Notice that the load balance is important for reducing the peak power requirement of a switch, so we also propose in this paper two new routing algorithms for optical multi-log2N networks to achieve a better load balance. [ABSTRACT FROM AUTHOR]

Nowadays, collaborative product development has become a strategic necessity to develop high quality products at low cost and with quick response time to market demand. Past decades have seen significant advances to collaborative product development. However, Enterprises are still confronted with some problems. Firstly, the research in strategic level of collaborative product development is lacking. There are no formal processes and models for collaborative product development. On the other hand, the full alignment between information system and collaborative business is still missing. The information system cannot adapt to the fast changed business. This paper aims to provide the strategy and reference business model for collaborative product development. And then, to support the implementation of strategy and model, a workflow and web service based engineering collaboration portal is developed. The workflow is used to model and execute the collaborative product development processes, and the web service is the implementing technology of the portal. The combination of workflow and web service can fit the gap between business and information system and achieve on-demand business. [ABSTRACT FROM AUTHOR]

The paper is devoted to application of formal concept analysis and collaborative design in shipbuilding. Sourcing and shoring strategies of a Norwegian multinational design company is illustrated by a concept lattice. [ABSTRACT FROM AUTHOR]

This paper presents a document recommendation system based on clustering peer-to-peer networks. It's an unstructured P2P system. In this system each agent-peer can learn user's interest, then it helps user share and recommend documents with the other users. Since each peer in our P2P networks is a node, in order to cluster them, we import the concept of Group. Each group is composed of peers. The types of documents, which belong to a same group, are uniform. This paper presents how these peers help users to share and to recommend documents, and how they cluster into groups. Our experiment results show the advantages of the document recommendation system. [ABSTRACT FROM AUTHOR]

This paper is focused on differential conversion, which is a new approach to data transformation between different software systems. The strategy of differential conversion, which is built on a log of changes and identifier mapping, was introduced in CDVE 2006 in a purely theoretical paper entitled Data Exchange in CAD during Iterative Work with Heterogeneous Systems. A specific case study of differential conversion in use is elaborated in this text. It is about an intelligent bi-directional transformation between DWG and SVG. DWG is a proprietary CAD-format of the AutoCAD system, whereas SVG is an open, generic graphics format, based on XML. The implemented transformation allows usage of a model created in a CAD-system within a cooperative design intended for non-CAD users. It is useful not only for reading, but even for writing into the model and modifying it. Any changes made are returned back to the original model. The following case exemplifies the previously discussed strategy. For example, a project submitter, or another party in the review process, can use a normal, generic SVG editor for writing comments and proposals into the model. A solver can transform them back into the CAD-model, without other entities in the model being damaged. This case study describes differential export and import tools and takes note of the particular solutions of the log of changes and identifier mapping problems. It also describes the relationship to the original differential conversion proposal, discusses the particular implementation, and again generalizes into some design pattern for differential conversion implementation projects in the conclusion. [ABSTRACT FROM AUTHOR]

As the complexity of application system for enterprises, an important challenge is to dynamically schedule and integrate the heterogeneous and distributed services or activities to work cooperatively and efficiently. An effective technology to resolve the problem is grid service. A grid service built on both grid computing and web services technologies is an extended Web service. An application system for enterprises is a grid service composition that consists of a collection of grid services related by data and control flow. Therefore, there is a need for modeling and analyzing techniques and tools for reliable and effective grid service composition. The Petri net based method is an idea approach. In this paper, we use a colored dynamic timed Petri net (CDTPN) to model the grid service composition. The definition of CDTPN for grid service and an algorithm to construct a composite service are proposed. We give a definition of reachable service graph and an algorithm for constructing the reachable service graph of CDTPN. Finally, we discuss the correctness and effectiveness of the grid service composition by analyzing the reachable service graph. [ABSTRACT FROM AUTHOR]

Collaborative team members usually come from diverse disciplines; their demands for knowledge are also different from each other. This paper is mainly concerned with how to capturing designers' knowledge demands in collaborative team. With the view from workflow, designers' knowledge demand is modeled from three aspects, members, roles, and tasks' requirements for knowledge. Based on the model of knowledge demand, some intelligent mining methods are proposed so that designers' knowledge demand could be derived automatically. With the knowledge demand model, a knowledge supply system could be developed to realize: knowledge within an appropriate domain could be delivered to the proper user among the collaborative team. [ABSTRACT FROM AUTHOR]

One of the challenges for ubiquitous computing is to design systems that can be both understood by their users and at the same time understand the users themselves. As information and its meaning becomes more associated with the communities that provide and use it, how will it be possible to build effective systems for these users? We have been examining these issues via ethnographic analysis of the information and community supporting system that we have developed and employed at conference events. This paper presents initial analysis and suggests greater focus on the interaction between members of micro-communities of users in future ubicomp research. [ABSTRACT FROM AUTHOR]

Over the last decade, new information and communication technologies have lived a secret life. For individuals and institutions around the world, this constellation of mobile phones, personal computers, the internet, software, games, and other computing objects have supported a complex set of religious and spiritual needs. In this paper, I offer a survey of emerging and emergent techno-spiritual practices, and the anxieties surrounding their uptake. I am interested in particular in the ways in which religious uses of technology represent not only a critique of dominant visions of technology's futures, but also suggest a very different path(s) for ubiquitous computing's technology envisioning and development. [ABSTRACT FROM AUTHOR]

Although security has been recognized as an increasingly important and critical issue for software system development, most security requirements are poorly specified: ambiguous, misleading, inconsistent among various parts, and lacking sufficient details. In this paper, a framework for specifying unambiguous, interoperable security requirements and detecting conflict and undesirable emergent properties in collaborative systems is presented. The framework includes a core ontology representing hierarchical security requirements , an ontology-based security requirement specification process, a set of security requirement refining rules, an algorithm for automatic security requirement refinement and an analysis algorithm to detect inconsistent security requirements. In this paper, the specification and refinement of security requirements are emphasized. Keywords: Software security, security specification, hierarchical security requirements, framework, collaborative systems, ontology, requirement refinement algorithms [ABSTRACT FROM AUTHOR]

In this paper, we consider the selfish routing problem in non- cooperative wireless mesh networks where the capacity can be improved by transmitting over multiple radios simultaneously using orthogonal channels. The problem is that there are some agents who are in charge of their transmissions and each of them is selfish to minimize its own transmission cost without considering the overall performance of the network. But the embarrassment in wireless mesh networks is that the selfish agents perhaps may cause interference for the non-cooperation. We think that the game theoretic tools are helpful for the selfish agents to make feasible choices. We yield a sufficient condition of the existence of pure strategy Nash equilibrium in our Strong Transmission Game and prove it in this paper. Some simulations reveal the feasibility of our game theoretic approach. [ABSTRACT FROM AUTHOR]

This paper presents an autonomic group location update (GLU) scheme for next-generation mobile networks. The GLU scheme takes account of the cooperative ability of the Mobile Terminals(MTs) in next-generation mobile networks, thus employs an autonomic group formation method to report location update in groups. A Leader Mobile Terminal(LMT) is elected out of all Group Members(GMs) to perform the location update and administration tasks for the whole group. Not only the bandwidth is saved for the efficiency of group operation, but also the whole system energy consumption of location update is significantly reduced in respect that communication range is much shorter in group than to base station. A leader rotation algorithm based on a variable called prestige is also exploited to make it fair. Both analysis and simulation show that the GLU scheme greatly saves energy for MTs and with our leader rotation algorithm, fairness can be also achieved. [ABSTRACT FROM AUTHOR]

I/O-driven integration applications, such as EAI, B2Bi, home gateways, and heterogeneous devices integration, need a trustworthy integration framework to process a large volume of I/O-driven transactions with high performance and reliability. This paper proposes an integration framework for trustworthy transactions. This framework employs a design pattern, so-called, the Worker-Linker pattern, that is used for performance stability. According to our experimental results, the pattern helps the integration framework to control the heavy load after the saturation point. Moreover, this framework supports a number of mechanisms for trustworthy integration transactions. In this paper, we describe the mechanisms. [ABSTRACT FROM AUTHOR]