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This paper proposes a novel resource management framework that integrates Call Admission Control (CAC) and aggregate reservation of bandwidth for mobile networks in a scalable fashion. Our proposal avoids per-user reservation signaling overhead and takes into account the expected bandwidth to be used by calls handed off from neighboring cells within a prediction interval through the Trigg and Leach Method (an adaptive exponential smoothing technique). Our scheme is compared through simulations with the ACR (Adaptive Channel Reservation) scheme, a dynamic reservation-based proposal that uses GPS systems to extrapolate users' movement and to trigger reservations in the next predicted cell. The simulation results show that our proposal provides the best performance in terms of handoff dropping probability and can achieve similar levels of call blocking probability as compared to ACR. In addition, our proposal can grant an upper bound on handoff dropping probability even under very high loads. [ABSTRACT FROM AUTHOR]

This paper addresses the issue of multicast communication in scalable interconnection networks, using path-based scheme. Most existing multicast algorithms either assume a fixed network size, low dimensional networks or only consider the latency at the network level. As a consequence, most of these algorithms implement multicast in a sequential manner and can not scale well with the network dimensions or the number of nodes involved. Furthermore, most of these algorithms handle multicast communication with low throughput. In this paper, we propose a multicast algorithm for multidimensional interconnection networks, which is built upon our Qualified Groups QG multicast scheme for ensuring efficient communication irrespective of the network sizes/dimensions or the number of the destination nodes. Unlike the existing works, this study considers the scalability and latency at both the network and node levels so as to achieve a high degree of parallelism. Our results show that the proposed algorithm considerably improves the multicast message delivery ratio, throughput and scalability. [ABSTRACT FROM AUTHOR]

In this paper, we apply the hierarchical concept to the Care-of Prefix (CoP) scheme as HCoP and enhance HCoP with a novel Binding Update Tree (BUT) structure as HCoP-B for NEtwork MObility (NEMO) management of the nested mobile network. As compared to schemes such as Reverse Routing Header (RRH), Route Optimization using Tree Information Option (ROTIO) and HCoP with numerical performance evaluations, HCoP-B achieves the shortest handoff latency and significantly reduces the consumed network bandwidth of global binding update messages for route optimizations (RO) of all correspondent nodes (CN) after the nested mobile network hands over to a new AR. Consequently, HCoP-B resolves the RO storm problem. [ABSTRACT FROM AUTHOR]

Multiple non-overlapped channels are available in IEEE 802.11 but are rarely used today in wireless multi-hop networks. Wireless mesh network is a special type of multi-hop ad hoc network and is envisioned to provide high capacity and large coverage. In this paper, we propose a 2-hop clustering based multi-interface, multi-channel network architecture and design a novel channel assignment algorithm and routing metric. Channel assignment is composed of Inter-cluster Static Assignment and Intra-cluster Dynamic Assignment. Since traditional routing metrics, such as hop-count, may not perform well in multi-channel wireless networks, we propose the CDM routing metric, which combines hop-count, channel diversity and channel switching capability together. Simulation results show that our algorithms achieve up to 3.3 times higher end-to-end throughput. [ABSTRACT FROM AUTHOR]

Mobile SCTP (mSCTP) has been proposed to support transport layer mobility management. In this paper, we proposed a dynamic handover mechanism named Contention-based mSCTP (C-mSCTP) in the contention based wireless network. The handover strategy in C-mSCTP takes wireless bandwidth and the contention probability into account to set the primary path before transmitting data. The simulation results show that the C-mSCTP achieves much better performance in terms of transmission delay and throughput than mSCTP does. [ABSTRACT FROM AUTHOR]

In WDM mesh networks, low-speed data streams from individual users are combined, using the techniques of traffic grooming, for efficient utilization of the high bandwidth of a lightpath. The objective of traffic grooming is to minimize the cost of the network and/or to maximize the network throughput. Proposed solutions for this optimization problem are computationally intractable, even for networks of moderate size. In this paper, we have presented efficient Integer Linear Program (ILP) formulations for traffic grooming on mesh WDM networks, one for minimizing the congestion and the other to maximize the throughput of the network, with an assumption that the logical topology is specified. Unlike previous formulations, our formulations can be used for practical sized networks. We have simulated our formulations with networks up to 30 nodes, and with hundreds and even thousands of low-speed data streams and have shown that the formulations are able to generate optimal solutions within a reasonable amount of time. [ABSTRACT FROM AUTHOR]

By means of analysis and generalization of the hypercube and its variations of the same topological properties and network parameters, a family of interconnection networks, referred to as binary recursive networks, is introduced in this paper. This kind of networks not only provides a powerful method to investigate the hypercube and its variations on the whole, but also puts forth an effective tool to explore new network structures. A constructive proof is presented to show that binary recursive networks are Hamiltonian based on their recursive structures, and an approach to prove 4-pancyclicity of a subfamily of binary recursive networks is outlined. [ABSTRACT FROM AUTHOR]

A category of wireless sensor networks consists of lots of autonomous sensor nodes with limited power and few base stations with theoretically unlimited power. A number of redundant nodes are usually deployed densely in these types of networks in order to provide redundancy for sensing and communications. There is a challenge though of which nodes must be active and which ones must be asleep, without compromising the coverage and network connectivity. To get round this challenge, each node should somehow know the position of its immediate neighbors. Previous researches have impractically assumed the existence of a GPS module in each node, which is in direct contradiction with the main constraints of low cost and size of sensor nodes. This paper proposes an energy saving solution without requiring the nodes to possess any physical GPS. The goal is to minimize the number of active sensors with respect to coverage and connectivity. Each node decides locally by itself whether to be active or not. There is no need for any global synchronization between nodes. Simulation results show that the higher density of nodes in our proposed solution leads to better coverage, higher energy saving and longer network lifetime. [ABSTRACT FROM AUTHOR]

The monitor construct has been implemented in several concurrent and/or parallel programming languages for shared-memory system environments, Extensions of the monitor to support process synchronization in distributed systems have also been proposed. But, most existing work only provides the architecture design of the distributed monitor. There is no discussion about the algorithmic and implementation issues. Also, none of them consider how to implement conditional variables. In this paper, we present the design and implementation of a distributed monitor construct, named DisMoniC, for programming process synchronization in distributed systems. DisMoniC is generic in the sense that it can be used with any distributed mutual exclusion (DME) algorithm to implement exclusive access to the monitor operations. Time-efficient algorithms are proposed to implement conditional process synchronization in the distributed monitor. We also present performance evaluation of the proposed construct. [ABSTRACT FROM AUTHOR]

The performance of contiguous allocation strategies can be significantly affected by the distribution of job execution times. In this paper, the performance of the existing contiguous allocation strategies for 3D mesh multicomputers is re-visited in the context of heavy-tailed distributions (e.g., a Bounded Pareto distribution). The strategies are evaluated and compared using simulation experiments for both First-Come-First-Served (FCFS) and Shortest-Service-Demand (SSD) scheduling strategies under a variety of system loads and system sizes. The results show that the performance of the allocation strategies degrades considerably when job execution times follow a heavy-tailed distribution. Moreover, SSD copes much better than FCFS scheduling strategy in the presence of heavy-tailed job execution times. The results also show that the strategies that depend on a list of allocated sub-meshes for both allocation and deallocation have lower allocation overhead and deliver good system performance in terms of average turnaround time and mean system utilization. [ABSTRACT FROM AUTHOR]

To gain high performance computing or store large amount of data using inexpensive devices, grid system is one of the well-known solutions. In most cases, the grid can be categorized into two types: computational grid and data grid. Data grid is used for data intensive applications. In data grids, replication is used to reduce access latency and bandwidth consumption. Furthermore, it can also improve data availability, load balancing and fault tolerance. If there are many replicas, they may have coherence problems while being updated. In this paper, based on the aggressive-copy method, we propose a novel Greedy Pipeline-based Aggressive Copy (GPAC) protocol. The performance of pipelining dataset blocks and greedy sequencing in the GPAC can accelerate data replication speed in compared with previous works. Both analytical and experimental results show promising performance enhancements. [ABSTRACT FROM AUTHOR]

In 2003, Shim proposed an efficient ID-based authenticated key agreement protocol based on Weil pairings [1]. Sun et al. raised the potential of a man-in-the-middle attack in [2]. In 2004, Ryu et al. proposed an efficient ID-based authenticated key agreement protocol from pairings [3]. In 2005, however, Boyd et al. noted security problems of Ryu et al.'s protocol in [4]. In 2005, Yuan et al. also pointed out the same weakness [5] in Ryu et al.'s protocol. Then, they proposed a new protocol that combines Ryu et al.'s protocol with Shim's protocol. In this paper, we demonstrate that Shim's protocol does not provide KGC forward secrecy, then we propose a more efficient and secure protocol which does provide such security. As a result, our protocol does not need an additional ECC point-addition unlike Yuan et al.'s protocol and our's can generate two secure session key to perform the secure message transmission. [ABSTRACT FROM AUTHOR]

We have been developing a secure and reliable distributed storage system, which uses a secret sharing scheme. In order to efficiently store data in the system, this paper introduces an optimal share transfer problem, and proves it to be, generally, NP-hard. It is also shown that the problem can be resolved into a Steiner tree problem. Finally, through computational experiments we perform the comparison of heuristic algorithms for the Steiner tree problem. [ABSTRACT FROM AUTHOR]

The concept of XML views is proposed to integrate heterogeneous data sources in XML, and a global XML view can represent the distributed heterogeneous data sources as single XML document. XQuery is one of the standard query languages for searching XML data. How to process efficiently of global XQuery queries, which are written under a global XML view, emerges as a new research topic. Popular techniques of distributed query processing are based on decomposition, and static decomposition is one of the processing techniques for the traditional query language. However, XQuery has a complex syntax such as FOR clauses that are not supported by other query languages, and its structural complexity causes some considerations for the decomposition of global XQuery queries. In this paper, we propose a method to decompose a global XQuery query into local XQuery queries and to construct the result of the global XQuery query from the results of the local XQuery queries. [ABSTRACT FROM AUTHOR]

This paper describes formal verification and quantitative performance evaluation for validating of query pattern-based relational schema-to-XML Schema translation (QP-T) algorithm. Many translation algorithms such as FT, NeT, CoT, ConvRel, and VP-T have been introduced on structural and/or semantic aspect for exact and effective translation. However, conventional algorithms consider only explicit referential integrity specified by relational schema or limitations regarding on reflection of implicit referential integrity information. It causes several problems such as incorrect translation, abnormal relational model transition, and so on. The QP-T algorithm analyzes query pattern and extract implicit referential integrities by interrelationship of equi-join in user queries. The QP-T algorithm can make up for weak points of the VP-T algorithm and create more exact XML Schema as a result by using with VP-T algorithm together. [ABSTRACT FROM AUTHOR]

Network-on-chip (NoC) is being proposed as a scalable and reusable communication platform for future SoC applications. The NoC, somewhat, resembles the parallel computer network. However, the NoC design highly requires the certain satisfaction of latency, power consumption, and area constraints. The latency of the network relates much to throughput and power consumption. Moreover, the IPs and the network are heterogeneous. Hence, a certain mapping of IPs onto a certain architecture produces a certain value of network latency as well as power consumption. The change of mapping scheme leads to a significant change of the values of these constraints. The fact that if we want to maximize the system's throughput, the network latency also increases and if we minimize the network latency, the trade off is that the throughput will decrease. In this paper, we present an mapping scheme that does compromise between throughput maximization and latency minimization. This sub-optimal mapping is found using the spanning tree searching algorithm. The experiment architecture using here is Mesh based topology. We use NS2 to simulate and calculate the system throughput and system power consumption is calculated using Orion model. [ABSTRACT FROM AUTHOR]

SCSI RDMA Protocol (SRP) is used to build high performance Storage Area Networks (SANs) over InfiniBand, or SRP-based IB-SANs for short. The I/O read performance is critical for many read dominant applications, such as multimedia, remote sensing, data backup, etc. However, if I/O accesses focus on a specific storage device of an IB-SAN, the local I/O performance of single device could become the bottleneck, leaving the network performance under utilized. In this paper, we propose an SRP target mode called Target Disk Cache Assisted (tDCA) mode, which explores the file read-ahead feature and page cache of Linux to tackle the performance gap between storage devices and network. Experimental results show that this strategy improves the read performance in terms of throughput which is increased significantly for both random read with good locality and sequential read. [ABSTRACT FROM AUTHOR]

A coloring of a graph G = (V,E) is a partition of {V1,V2 ⋯ Vk} of V into k independent sets called color classes. A vertex v ∈ Vi is called a Grundy vertex if it is adjacent to at least one vertex in color class Vj, for every j < i. In the partial Grundy coloring, every color class contains at least one Grundy vertex. Such a coloring gives a partitioning of the graph into clusters for which every cluster has a clusterhead (the Grundy vertex) adjacent to some other clusters. Such a decomposition is very interesting for large distributed systems and networks. In this paper, we propose a distributed algorithm to maintain the partial Grundy coloring of any graph G when an edge is added [ABSTRACT FROM AUTHOR]

The Cell processor is a typical example of a heterogeneous multiprocessor-on-chip architecture that uses several levels of parallelism to deliver high performance. Closing the gap between peak performance and sustained performance is the challenge for software tool developers and the application developers. Image processing and media applications are typical "main stream" applications. In this paper, we use the Harris algorithm for detection of points of interest (PoI) in an image as a benchmark to compare the performance of several parallel schemes on a Cell processor. The impact of the DMA controlled data transfers and the synchronizations between SPEs explains the differences between the performance of the different parallelization schemes. These results will be used to design a tool for an efficient mapping of image processing applications on multi-core architectures. [ABSTRACT FROM AUTHOR]

Sparse matrix-vector multiplication (shortly SpMV) dominates the performance of many scientific and engineering applications. However, it tends to run much more slowly than its dense counterpart because the algorithms have poor temporal and spatial locality, the memory access patterns are irregular. Its performance depends heavily on both the nonzero structure of the sparse matrix and on the machine architecture. In this paper, we address the problem of implementing and optimizing SpMV on Imagine stream processor. We present three classes of implementation algorithms based on different key ideas, first two of which highlight different aspects of underlying stream architecture, and the third algorithm is inspired by the SpMV vector implementation. Then we discuss some critical optimizations. The experimental results over same benchmarks show we achieve up to an average 67 percent relative improvement over published evaluation. [ABSTRACT FROM AUTHOR]

In this paper a real and complex transportation problem including routing, scheduling and loading tasks is presented. Most of the related works only involve the solution of routing and scheduling, as a combination of up to five different types of VRPs (Rich VRP), leaving away the loading task, which are not enough to define more complex real-world cases. We propose a solution methodology for transportation instances that involve six types of VRPs, a new constraint that limits the number of vehicles that can be attended simultaneously and the loading tasks. They are solved using an Ant Colony System algorithm, which is a distributed metaheuristic. Results from a computational test using real-world instances show that the proposed approach outperforms the transportation planning related to manual designs. Besides a well-known VRP benchmark was solved to validate the approach. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new structured P2P overlay network, named SW-Uinta, where employs a non-deterministic caching strategy that allows for polylogarithmic search time while having only a constant cache size. Compared with deterministic caching strategies proposed by previous P2P systems, the non-deterministic caching strategy can reduce communication overhead for maintaining the routing cache table. Cache entries in the peer can be updated by subsequent queries rather than only by running stabilization periodically. A novel cache replacement scheme is used to improve lookup performance. We compare the performance of our system with that of other structured P2P networks such as Chord and Uinta. It shows that the SW-Uinta protocol can achieve improved object lookup performance and reduce maintenance cost compared with some other protocols. [ABSTRACT FROM AUTHOR]

In order to classify data with noises or outliers, Fuzzy support vector machine (FSVM) improve the generalization power of traditional SVM by assigning a fuzzy membership to each input data point. In this paper, an improved FSVM based on vague sets is proposed by assigning a truth-membership and a false-membership to each data point. And we reformulate the improved FSVM so that different input points can make different contributions to decision hyperplane. The effectiveness of the improved FSVM is verified in credit rating; the experiment results show that our method is promising. [ABSTRACT FROM AUTHOR]

Parallelism is one of the main sources for performance improvement in modern computing environment, but the efficient exploitation of the available parallelism depends on a number of parameters. Determining the optimum number of threads for a given data parallel loop, for example, is a difficult problem and dependent on the specific parallel platform. This paper presents a learning-based approach to parallel workload allocation in a cost-aware manner. This approach uses static program features to classify programs, before deciding the best workload allocation scheme based on its prior experience with similar programs. Experimental results on 12 Java benchmarks (76 test cases with different workloads in total) show that it can efficiently allocate the parallel workload among Java threads and achieve an efficiency of 86% on average. [ABSTRACT FROM AUTHOR]

Traffic sampling technology has been widely deployed in front of many high-speed network applications to alleviate the great pressure on packet capturing.Increasingly passive traffic measurement employs sampling at the packet level. Packet sampling has become an attractive and scalable means to measure flow data on high-speed links. However, knowing the number and length of the original flows is necessary for some applications. This paper provides a novel algorithm, Least Square Method(LSM), that uses flow statistics formed from sampled packet stream to infer the absolute frequencies of lengths of flows in the unsampled stream. The theoretical analysis shows that the computational complexity of this method is well under control, and the experiment results demonstrate the inferred distributions are as accurate as EM algorithm. [ABSTRACT FROM AUTHOR]

Java is widely applied into embedded devices. Java programs are compiled into Java bytecodes, which are executed into the Java virtual machine. The Java virtual machine is a stack machine and instruction folding is a technique to reduce the redundant stack operations. In this paper, a simple instruction folding algorithm is proposed for a Java processor named jHISC, where bytecodes are classified into five categories and the operation results of incomplete folding groups are hold for further folding. In the benchmark JVM98, with respect to all stack operations, the percentage of the eliminated P and C type instructions varies from 87% to 98% and the average is about 93%. The reduced instructions are between 37% and 50% of all operations and the average is 44%. [ABSTRACT FROM AUTHOR]

Network processors are specialized integrated circuits used to process packets in such network equipment as core routers, edge routers, and access routers. As predicted by Gilder's law, Internet traffic has doubled each year since 1997 and this trend is showing no signs of abating. Since all emerging network applications which require deep packet classification and security-related processing should be run at line rates and since network speed and network applications complexity continue increasing, future network processors should simultaneously meet two requirements: high performance and high programmability. Single processor performance will not be sufficient to support the requirements which will be imposed on future network processors. In this paper, we consider the CMP model as the baseline architecture of future network processors. We investigate the architectural implications of cache coherence protocols with network workloads on CMPs. Our results show that the token protocol which uses the tokens to control read/write permission of shared data blocks shows better performance than the directory protocol by a factor of 13.4%. [ABSTRACT FROM AUTHOR]

Almost all cryptographic file sharing systems need re-encryption when the sharing was revoked. These systems differ from each other only in the timing of re-encryption. As re-encryption is an expensive operation, it is significant to avoid re-encryption. The purpose of this paper is to advise a direction to avoid re-encryption and facilitate file sharing in cryptographic file sharing system. A Black-box model is set up to achieve this objective. In the model, FPGA or ASIC chips are used to act as the black-box as they have been extensively researched and applied in cryptography. Some applications of FPGA and ASIC in cryptography are detailed in this paper. Their feasibility to be functioned as the black-box is discussed. Also a software implementation on FPGA is attached with tested and effective performance. [ABSTRACT FROM AUTHOR]

The current storage models for Object-Oriented DataBase (OODB), which organize data as objects according to the Object-Oriented Data Model (OODM), are mainly established on the block storage devices. In this way, the storage manager does not have detailed knowledge of the characteristics of the underlying storage devices, and the storage subsystem does not have the semantic knowledge of the data stored in the block storage devices, so it is very difficult to implement some workload-dependent tasks such as data layout and caching. Furthermore, the storage subsystem of OODB has to organize the objects in the pages, which is not well-suited to the objects storage. In this paper, we present an Object-Based Storage Model (OBSM) for OODB by using the recently-standardized Object-based Storage Device (OSD) interface. OSD offloads the storage management into the storage device itself and provides an object interface to data, which brings more intelligence into the storage subsystem. In the first glance at using OBSD in OODB, we explore the methods to map OODM to OBSM including direct mapping, mapping clustering to collection and declustering a large object to a series of sub-objects, and analyze the benefits to the storage subsystem of OODB by using OBSM such as providing storage functionalities offloading, providing objects sharing pool, providing integrative object persistence. [ABSTRACT FROM AUTHOR]

In the fast-growing internet applications, email becomes more and more important in communication. SMTP attacks and spam have become one of the most serious problems. Particularly, the SMTP attacks and spam varies on email, for example spoofing address, illegal characters, sending in bulk, too many SMTP commands and so on. A single security technique is not enough to protect the system from these attacks and spam. In this paper, we propose a SMTP Intrusion Prevention System (SIPS) which bases on the concept of Stateful Protocol Anomaly Detection and Flow-based Inspection. SIPS is implemented by a finite state machine to inspect all coming email flows. It is according to the media type of email flow and their characteristics. On the test of a real email environment, our approach can prevent attacks on SMTP attack (mail bomb) average about 95.4% and spam average about 91.1%. [ABSTRACT FROM AUTHOR]

This paper proposes a novel scheme of group key management based on Jacobian Elliptic Chebyshev Rational Map, named Jacobian Group Key Management(JGKM). The scheme is more efficient than other group key managements since fewer re-keying messages are sent when group membership changes. Besides, it provides both forward and backward secrecy. Therefore, this proposal is helpful to deploy secure multicast over some networks with high latency or limited bandwidth such as wireless network. Furthermore, it fits both small-scale and large-scale groups. [ABSTRACT FROM AUTHOR]

An important issue in deploying a wireless sensor network (WSN) is to provide target coverage with high energy efficiency and fault-tolerance. In this paper, we study the problem of constructing energy-efficient and fault-tolerant target coverage with the minimal number of active nodes which form an m-coverage for targets and a k-connected communication subgraph. We propose two heuristic algorithms for m-coverage problem, and get the performance ratio of one heuristic. Then two heuristic algorithms are further proposed to solve the k-connected m-coverage problem. The simulation results demonstrate the desired efficiency of the proposed algorithms. [ABSTRACT FROM AUTHOR]

In this paper, by introducing knowledge of fuzzy mathematics, probability theory and gaming theory, a QoS unicast routing scheme with ABC supported is proposed based on small-world optimization algorithm. Under inaccurate network status information and imprecise user QoS requirement, the proposed scheme uses the range to describe the user QoS requirement and the edge parameter, introduces the user satisfaction degree function, the edge evaluation function and the path evaluation function, trying to find a QoS unicast path with Pareto optimum under Nash equilibrium on both the network provider utility and the user utility achieved or approached. Simulation results have shown that it is both feasible and effective with better performance. [ABSTRACT FROM AUTHOR]

In this paper, we propose a modulation multiplexing distributed space-time coding for two-user cooperative diversity in wireless network, in which the information of one user lies in the in-phase axis (I axis), while that of the other user lies in quadrature-phase axis (Q axis). Since two users share both time and frequency resource in cooperation sub-frame, the proposed scheme is more bandwidth efficient. We characterize performance of the proposed scheme in symmetric inter-user case. Simulation results show that the proposed scheme outperforms the amplify-to-forward cooperative system. Compared to the distributed space-time coding with time-division multiple accesses cooperative system, the proposed scheme achieves the same diversity gain but loses some coding gain. However, when the selection relay protocol is adopted for the proposed scheme, coding gain is also achieved. [ABSTRACT FROM AUTHOR]

The geographic routing technology is good for the self-organizing and large-scale Wireless Sensor Networks(WSNs), and the energy-limited sensor nodes require the energy used for routing to be minimum. In this paper a new energy-efficient geographic routing algorithm is proposed and it is distributed and based on the geographic routing, the topology characteristics of the network and the wireless communication energy model. The algorithm is based on the planarized graph (GG) of the network, it deals with the routing void by saving more face neighbors in every node, and selects the most energy-efficient nexthop node by using the energy-saving technologies including the Minimum Energy One-hop Neighbor Path Selection and the Optimal Face-neighbor Selection. The theoretical analysis and simulations show that the algorithm is feasible and more energy-efficient than many existed geographic routing algorithms. In the end , the means of face information maintenance are proposed. [ABSTRACT FROM AUTHOR]

Currently, people can collect information and share resources on the Internet through WiFi. The Voice over Internet Protocol (VoIP) supported by wireless technology has made Internet access more versatile and flexible than before. However, the more sessions established for communication, the longer the transmission delay and the higher the packet dropping rate. In this paper, an improved bandwidth utilization approach developed on the IEEE 802.11e standard is proposed. Experimental results show that this approach significantly improves a system's throughput as compared with 802.11b and other schemes. [ABSTRACT FROM AUTHOR]

This paper proposes a new method to find an absolute position by using ultrasonic sensors. In order to evaluate the performance of U-SAT (Ultrasonic Satellite system), the autonomous navigation performance of a mobile robot is tested. Experiments were performed in both cases that the mobile robot moves to the target point using relative positioning method in conjunction with U-SAT, which is, absolute positioning methods. The performance of U-SAT is evaluated accordingly with the results of the experiments. As a result, U-SAT could be effectively used as a pseudolites or pseudo-satellites to help a mobile robot navigate intelligently and autonomously in an indoor area. [ABSTRACT FROM AUTHOR]

Slowdown factors determine the extent of slowdown a computing system can experience based on functional and performance requirements. Dynamic Voltage Scaling (DVS), which adjusts the clock speed and supply voltage dynamically, is an effective technique in reducing the energy consumption of embedded real-time systems. We address the problem of computing static and dynamic slowdown factors in the FPPT algorithm. In this paper, Sufficient constraints have been identified for the feasibility of the task set using slowdown factors. We formulate this problem of computing the static slowdown factors for tasks as an nonlinear optimization problem to minimize the total energy consumption of the system. Our simulation experiments show on an average 17%~53% energy gains over FPPT scheduling policy. [ABSTRACT FROM AUTHOR]

Vertically stacked optical banyan (VSOB) is an attractive architect-ture for constructing banyan-based optical switches. Blocking analysis is an effective approach to studying network performance and finding a graceful compromise among hardware cost, blocking probability and crosstalk tolerance; however, little has been done on analyzing the blocking behavior of VSOB networks under crosstalk constraint. In this paper, we study the overall blocking behavior of a VSOB network under various degree of crosstalk, where an upper bound on the blocking probability of the network is developed. The upper bound depicts accurately the overall performance behavior of a VSOB network as verified by extensive simulation results and it agrees with the strictly nonblocking condition of the network. The derived upper bound is significant because it reveals the inherent relationship between blocking probability and network hardware cost, by which a desirable tradeoff can be made between them under various degree of crosstalk constraint. Also, the upper bound shows how crosstalk adds a new dimension to the theory of switching systems. In particular, our bound provides network developers an effective tool to estimate the maximum blocking probability of a VSOB network in which different routing algorithms can be applied with a guaranteed performance in terms of blocking probability and hardware cost. An important conclusion drawn from our work is that the hardware cost of VSOB networks can be reduced dramatically without introducing significantly high blocking probability considering the crosstalk. [ABSTRACT FROM AUTHOR]

A notable requirement of clusters is to maximize its processing performance. Lots of work in this area has been done to optimize the system performance by improving certain metric such as reliability, availability, security and so on. However, most of them assumes that the system is running without interruption and seldom considers the system's intrinsic characteristics, such as failure rate, repair rate and lifetime. In this paper, we study how to achieve high availability based on residual lifetime analysis for the repairable heterogeneous clusters with makespan constraints. First, we provide an availability model based on addressing the cluster's residual lifetime model. Second, we give an objective function about the model and develop a heuristic scheduling algorithm to maximize the availability the makespan constraint. At last, we demonstrate these advantages through the extensive simulated experiments. [ABSTRACT FROM AUTHOR]

Collaborative testing is an effective way of distributed interoperability in pursuit of automated testing. In this paper, a novel collaborative testing approach named Collaborative Automated Testing Framework (CATF) which meets the requirements of not only automated testing but also collaborative operation is proposed. Through the abstract analysis in terms of extended dynamic dataflow (DDF) model's viewpoint incorporating with UML2.0 profile of MDA, we design the framework with an automated engine working as a Finite State Machine (FSM). Particularly, as a approach to collaborative testing at a system level, CATF is implemented with component modules based on J2EE and verified to be of efficiency. [ABSTRACT FROM AUTHOR]

Mobile computing system using mobile Web Services now supports advanced methods for application integration through the Internet at distributed computing environments. Mobile Web Services on mobile networks is the foundation for ubiquitous healthcare that gives patients better medical services anytime and anywhere. However, available existing web contents are mainly used for desktops on wired networks, but are not yet compatible with mobile Web Services. In this paper, we suggested the cooperative mobile healthcare information support system. The designed system can achieve the advanced inquiring manner of medical information for collaborate diagnosis at both desktop and mobile machines, and also afford to support wider accessibility of users over wireless and wired network environments. [ABSTRACT FROM AUTHOR]

Recently an integrated multiplatform system aiming at offering travel service over several communication channels is under development. A set of cooperating systems in completely different platforms will work together to provide integrated services to the clients anywhere and anytime. The structure, communication environment, some special issues and implementation of the system are discussed in the paper. [ABSTRACT FROM AUTHOR]

This paper proposes a systematic approach to integrate domain-dependent design tools in artificial bone scaffolds process. Integrated solution of CAD modelling and properly analysis of biomedicine knowledge are utilized to design complicated bone scaffolds. FEA and CFD are comprehensively analyzed for the mechanical and internal micro circulation properties. A case study of a successful artificial bone scaffolds model demonstrates that the cooperative design methodology can facilitate the design in the multi-physics domain substantially. [ABSTRACT FROM AUTHOR]

Collaborative simulation technology is an important factor in improving the efficiency of complex product design. Although High Level Architecture (HLA)-based simulation technology can meet the needs for simulation in product design, it's also marked by many deficiencies. In this paper, we focus on the introduction of web services into HLA simulation system and propose a Web Services-Based HLA Collaborative Simulation Framework (WSHLA). The framework uses web services to encapsulate the invocations of HLA services and then make simulation system more interoperable and reusable. Firstly, the overall structure of WSHLA and the proxy, which acts on behalf of a federate and interacts with Runtime Infrastructure (RTI), are presented. Then, the detailed design and implementation process of WSHLA are discussed. Experimental results show that, using web services, the framework can make up for the deficiencies in HLA simulation system and ensure WSHLA-based collaborative simulation goes smoothly at the expense of some time. [ABSTRACT FROM AUTHOR]

In workflow and grid environment, the security challenges with the appearance of composite service increasingly become more severe than before especially to the traditional static access control model and dynamic authorization model. To solve these challenges, we presented a Dynamic Access Control Prediction mechanism for service workflow on the basis of Markov Chain. In fact, this prediction mechanism is only one part of the larger system, Composite-Service Authorization Prediction platform (CAP), which is totally composed of three key modules-— composite-service pre-processing, result feedback, and authorization prediction. In this paper, we present the design of its architecture as a whole. [ABSTRACT FROM AUTHOR]

The authors of this paper participated in the project Framework 6 Intelligent Cities and the Lincoln Institute of Land Policy Fellowship. One of the above project's goals was to develop and improve a Real Estate's Market Value, and the Pollution and Health Effects Analysis Decision Support System (RE-MVPHE-DSS). RE-MVPHE-DSS consists of a market value analysis, air and noise pollution, premises microclimate, health effects, voice stress analysis, complex determination of the weights of the criteria, cooperative decision making and multiple user subsystems. RE-MVPHE-DSS is briefly analysed in this paper. [ABSTRACT FROM AUTHOR]

Organizations are under increasing pressures to manage all of the personal data concerning their customers and employees in a responsible manner. With the advancement of information and communication technologies, improved collaboration, and the pressures of marketing, it is very difficult to locate personal data is, let alone manage its use. In this paper, we outline the challenges of managing personally identifiable information in a collaborative environment, and describe a software prototype we call SNAP (Social Networking Applied to Privacy). SNAP uses automated workflow discovery and analysis, in combination with various text mining techniques, to support automated enterprise management of personally identifiable information. [ABSTRACT FROM AUTHOR]

This paper describes how information visualization techniques can be used to monitor a web-based collaborative platform and to support workplace awareness by providing a global overview of the activities. An innovative prototype is described. Its originality relies on using some enclosure-based visualization methods in the context of activities monitoring, which is rather unusual. In addition, a new layout is described for representing data trees. The use of the system is illustrated with the case of a EU-funded Network of Excellence. [ABSTRACT FROM AUTHOR]

With the development of new web technologies, web-based collaborative applications, exemplified by office applications, are emerging to take advantage of web's attractive features. We propose to plug a collaborative engine into web-based office applications so that advanced collaboration capabilities can be seamlessly integrated without compromising or modifying their conventional capabilities. This engine lies on application-independent data addressing and operation models to be reusable for a wide range of diverse applications without being modified. In this paper, we present a data addressing model for web-based word processors, which complies with the model used by the engine and shall lay a good foundation for investigating data addressing models for other web-based applications. [ABSTRACT FROM AUTHOR]