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The actual situation is that partners in virtual organisations rely upon a great variety of tools, which are not integrated, difficult to use and often ineffective. High costs are sustained to train the people and acquire tools of different make as required by the OEMs. The objective of the proposed paper is to present a conceptual model of an integrated engineering environment specifically tailored to the needs of the suppliers operating in a design network. The focal point is to show how monitoring and control of projects in virtual organisations can be supported. Therefore a Quality Control Management (QCM) concept will be presented that is able to provide several services in order to trace and control project processes and performance in an effective, integrated, easy to understand and user-friendly way. The approach presented in the proposed paper is basing on the work carried out by the European funded research project E4 (Extended Enterprise management in enlarged Europe — EC Contract No. IST-FP6-027282). [ABSTRACT FROM AUTHOR]

In this paper we analyze the use of different types of statistical tests for the correlation of anomaly detection alerts. We show that the Granger Causality Test, one of the few proposals that can be extended to the anomaly detection domain, strongly depends on good choices of a parameter which proves to be both sensitive and difficult to estimate. We propose a different approach based on a set of simpler statistical tests, and we prove that our criteria work well on a simplified correlation task, without requiring complex configuration parameters. [ABSTRACT FROM AUTHOR]

Since the millennium, a quickly increasing number of research papers in the field of "computational trust and reputation" have appeared in the Computer Science literature. However, it remains hard to compare and evaluate the respective merits of proposed systems. We argue that rigorous use of formal probabilistic models enables the clear specification of the assumptions and objectives of systems, which is necessary for comparisons. To exemplify such probabilistic modeling, we present a simple probabilistic trust model in which the system assumptions as well as its objectives are clearly specified. We show how to compute (in this model) the so-called predictive probability: The probability that the next interaction with a specific principal will have a specific outcome. We sketch preliminary ideas and first theorems indicating how the use of probabilistic models could enable us to quantitatively compare proposed systems in various different environments. [ABSTRACT FROM AUTHOR]

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]

This paper presents a literature survey of operational research applications to manufacturing logistics decision-making. A total of 80 applications published in Interfaces were reviewed in order to identify the decisions supported, their horizon, and their system boundary. The references to the papers reporting on these applications are included in the paper. Most OR applications were found in short-term production planning and scheduling, plant location and physical distribution system design, production system design, and master planning. Other areas, such as supplier selection and business process design, had few or no applications. While the survey sample does not allow generalizations, the unequal distribution of applications suggests that there is a rather clearly defined set of decision areas that are regularly supported by operational research. Findings also suggest that not only operational, but also certain strategic decisions, such as plant location, plant capacity and equipment capacity, are supported by OR. Finally, a lack of applications crossing organisational boundaries has been identified. [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]

Organisations want nowadays more controlled processes and easily usable solutions, but achieving them requires winning many challenges. Radio Frequency Identification (RFID) based technology has been proposed for improving mobile solution workflows and usability. NFC (Near Field Communication) technology is based on integrating RFID on mobile devices. This paper identifies how NFC based systems could be used to improve mobile solution workflows and usability. The results of this study are based on the implementation of six pilot cases in 2005-2007. This paper concludes that use of NFC provides both advantages and disadvantages and, therefore, to estimate the potential of NFC, its pros and cons have to be weighed up for each case in question. This paper also concludes that only a comprehensive solution achieves the full potential of NFC from users' point of view. Considering mobile solution usability, this paper concludes that NFC based solutions are easy to use, but the small and limited keyboard of mobile devices poses challenges to the design of these solutions. NFC use poses new organizational challenges like need for the rest of the system to catch up and feeling of distrust from the user side. [ABSTRACT FROM AUTHOR]

Let consider n autonomous mobile robots that can move in a two dimensional plane. The gathering problem is one of the most fundamental tasks of autonomous mobile robots. In short, given a set of robots with arbitrary initial locations, gathering must make all robots meet in finite time at a point that is not predefined. In this paper, we study about the feasibility of gathering by mobile robots that have φ-absolute error dynamic compasses. While the direction of each local coordinate system is fixed in usual systems, the dynamic compass model allows the angle difference between a local coordinate system and the global coordinate system to vary with time in the range of [0, φ]. This paper proposes a semi-synchronous gathering algorithm for n robots with (π/2 − ε)-absolute error dynamic compasses, where ε is an arbitrary small constant larger than zero. To the best of our knowledge, the proposed algorithm is the first one that considers both inaccurate compass models and more than two robots. We also show the optimality of our algorithm. It is proved that for any φ ≥ π/2, there is no algorithm to gather two robots with φ-absolute error dynamic compasses. [ABSTRACT FROM AUTHOR]

We investigate an automatic tuning method for an eigensolver of a dense symmetric matrix. The aim of this paper is to investigate how to select the unrolling depth. To do this, we evaluate the performance of various unrolled reduction loops of the eigensolver for every matrix size from 3000 to 4000 on the Hitachi SR8000/F1 and on the IBM RS/6000 SP3. We also analyze the trend between Byte/Flop and performance for various patterns of loop unrolling. The result shows that the performance is degraded with higher depth of unrolling in some matrix sizes, where it does not occur with lower depth of unrolling. The result also shows that selection of the unrolling depth should be examined in the case of several matrix sizes. [ABSTRACT FROM AUTHOR]

The digital watermark is used for detection of digital image alteration. However, most of digital images are printed on the paper document for submitting. Once digital images are printed on the paper, it is hard to detect alteration of it. In this paper, the detection method of printed image alteration by using digital watermark is proposed. [ABSTRACT FROM AUTHOR]

In this paper we introduce the problem of watermark security for systems in which an implementation of a watermark detector is available to an attacker. This paper serves as an introduction to a keynote talk at IWDW 2006. This talk will review two homomorphic encryption methods, viz. Paillier and Goldwasser & Micali, and their application to secure detection of Quantization Index Modulation (QIM) watermarks. [ABSTRACT FROM AUTHOR]

The International Manufacturing Strategy Survey (IMSS) have collected data in 1992, 1996, 2000, and 2006. The paper does longitudinell studies on these data focussing on data relevant for Lean Management. We see that there has been an adoption of the Just in Time and Lean issues, but that there is still a way to go. [ABSTRACT FROM AUTHOR]

With the establishment of the AES the need for new block ciphers has been greatly diminished; for almost all block cipher applications the AES is an excellent and preferred choice. However, despite recent implementation advances, the AES is not suitable for extremely constrained environments such as RFID tags and sensor networks. In this paper we describe an ultra-lightweight block cipher, present. Both security and hardware efficiency have been equally important during the design of the cipher and at 1570 GE, the hardware requirements for present are competitive with today's leading compact stream ciphers. [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]

This paper presents an efficient scheme maintaining a separator decomposition representation in dynamic trees using asymptotically optimal labels. In order to maintain the short labels, the scheme uses relatively low message complexity. In particular, if the initial dynamic tree contains just the root, then the scheme incurs an O(log3n) amortized message complexity per topology change, where n is the current number of nodes in the tree. As a separator decomposition is a fundamental decomposition of trees used extensively as a component in many static graph algorithms, our dynamic scheme for separator decomposition may be used for constructing dynamic versions to these algorithms. The paper then shows how to use our dynamic separator decomposition to construct rather efficient labeling schemes on dynamic trees, using the same message complexity as our dynamic separator scheme. Specifically, we construct efficient routing schemes on dynamic trees, for both the designer and the adversary port models, which maintain optimal labels, up to a multiplicative factor of O(loglogn). In addition, it is shown how to use our dynamic separator decomposition scheme to construct dynamic labeling schemes supporting the ancestry and NCA relations using asymptotically optimal labels, as well as to extend a known result on dynamic distance labeling schemes. [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]

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 describes an efficient scheme of probabilistic packet marking. The main idea is to preserve the victims' IP addresses at the routers participating in the packet marking scheme, based on the precondition that a router won't begin to marking until it receives a signal from the victim. Then, the destination address field of IP header can be used to carry edge information without fragmenting, and the identification field can be used to check attack paths' validity under DDoS. We describe the scheme and discuss the number of packets required for reconstructing the attack paths, the number of false positives of attackers and the extra cost at routers in this paper. [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]

The virtual region-based P2P architecture was provided in this paper, which extended the proximity concept in overlay network. By virtual region it meant various related factors should be integrated into the design of P2P topology, such as peer interest, peer locality, and heterogeneity in peer capacity etc. But, the shared contents in P2P are vast and miscellaneous, it is very difficult to recognize the interest similarity among peers, dynamically form the interest region and direct peer to appropriate interest region. In this paper, the Jensen-Shannon Divergence (JSD) was used to characterize interest/semantic similarity among peers, and the interest region formation and location mechanism based on Dynamic Interest Landmark (DIL) was offered to facilitate to dynamically guide peers to join the appropriate interest region corresponding to peers' content semantic. Considering that interest region is composed of geographically sporadic peers, each interest region was organized according to peer proximity in underlying infrastructure. The theoretical and simulated results illustrated that our architecture can significantly reduce the query overhead, and improve the search performance. [ABSTRACT FROM AUTHOR]

With new channels and devices based on ubiquitous computing, UCommerce provides an environment where buyers and sellers are literally able to commerce anytime, anywhere, and anyway they like. In U-Commerce, a lot of opportunities are expectable in various industrial areas, and especially in insurance industry. In this paper, we propose new types of insurance services in U-Commerce. And as a new channel to practice it, we propose Well-Bing Store with three concepts: ‘Corporeal Insurance Product', ‘U-Cart', and ‘Health Examination'. And supportive processes in Well-Being Store are depicted in detail as well. By introducing Well-Being Store, we transform a physical place into an intelligent space which cares insured customers previously before they get sick. This is actualized by managing a list of foodstuffs in a U-Cart accordingly, and by keeping a health examination regularly with help of an insurance company and a hospital. [ABSTRACT FROM AUTHOR]

This paper presents a Path Swapping (PS) method which enables to enhance the security of Quasi Delay Insensitive Asynchronous Circuits against Power Analysis (PA) attack. This approach exploits the logical symmetries of the QDI asynchronous blocks, particularly its data-path redundancies, to make all electrical curves used when implementing a PA attacks useless. Indeed, the idea is to average the electrical signatures of a block by randomly exchanging its data-paths during processing. To be able to implement this approach, we adopted a formal model of QDI circuits. Firstly, this formal model enables the designer to formally verify the symmetry of all paths in order to apply a path swapping method. Secondly, it offers the possibility to model the electrical signature of QDI asynchronous circuits. Finally, applying DPA on this formal model allows us to evaluate, in an early phase of the design, the circuit's sensitivity to the relevancy of the approach. Electrical simulations performed on a DES crypto-processor confirm the efficiency of the technique. Keywords: QDI Asynchronous circuits, Power analysis, Path Swapping (PS). [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]

Access structure is a flexible mechanism for representing complex access control and authorization policies [1]. Numerous efforts have been devoted to the research of efficient schemes for implementing access structures in a scalable manner. Threshold closure was invented as an efficient way to implement access structures that represent complex authorization policies [4]. In essence, threshold closure is an efficient and scalable implementation of access structure using a reduced collection of threshold schemes [5]. A practical application of threshold closure was presented in [6] where the use of threshold closure for addressing the complex security needs of Grid Computing Systems was explained. One major deficiency of threshold closure is that a threshold closure generated from the corresponding access structure is not minimal in size, thus the collection of threshold schemes is not optimized for efficiency. In this connection, an operation called minimal covering was proposed to minimize the size of a threshold closure once it is formed from its corresponding access structure [4]. Unfortunately, the minimal covering of a threshold closure is no longer a threshold closure, thus is not scalable in terms of addition/deletion of access control rules. This paper presents a way for constructing minimal threshold closure. It defines a new structure called enhanced threshold closure. The paper proves that the enhanced threshold closure of an access structure is a threshold closure and is minimal, hence it is also called a minimal threshold closure. The paper also presents a mechanism for constructing minimal threshold closure from a basis access structure. Keywords: Access Control, Authorization, Threshold Schemes, Threshold Closure. [ABSTRACT FROM AUTHOR]

This paper proposes a novel simulation-modeling framework that combines discrete-event simulations with system-dynamics simulations. The former represents both operational processes inside of a supply-chain, and the later represents management environment outside of a supply-chain. Further, the paper also discusses modeling capabilities of the proposed framework for supply-chain systems in real world by using several example simulation models. [ABSTRACT FROM AUTHOR]

In a fast changing environment, enterprises need to constantly refine their processes in order to effectively meet the requirements needed for achieving on-demand collaboration in order to win new opportunities as a result of market evolution. This paper introduces the global and common Workflow for cross-enterprises collaboration. A problem that stems from the global Workflow is the need to integrate running ad hoc processes whose descriptions unpredictably change to accommodate the business agility. Through this paper, we propose an approach based on synchronization points between processes of two or more enterprises. These points act as mediators to interface ad hoc processes without considering their definitions at the design time neither their evolution during the execution. A case study, relating to eprocurement, will illustrate the introduced concepts. [ABSTRACT FROM AUTHOR]

This paper presents the results of investigation of selected problems concerning Lean Manufacturing Implementation at SMEs in México. The analysis is a result of survey conducted in a sample of 24 manufacturing enterprises and it has been supported by some Mexican governmental information sources as well as additional studies which have been conducted before. The paper presents also a preliminary proposal of a methodology of implementation of lean manufacturing and the model of lean manufacturing appropriate in Mexican industrial plants conditions. The findings of this research are the following: a)The most important problems related to Mexican manufacturing SMEs, b) The problems related to the implantation of lean manufacturing in Mexican SMEs [ABSTRACT FROM AUTHOR]

Improving manufacturing operations is an initiative that all manufacturing firms need to engage in to stay competitive. The needs and ways to improve differ between companies. A thorough understanding of the operating characteristics is required for successful improvement of manufacturing operations. By modeling the plant or manufacturing system in a simulation model and create operating characteristics curves, it is possible to investigate trade-offs and improvement potentials that otherwise would be impossible to quantify by other means of analysis. This paper describes how to manage such an approach by using a simulation model of a manufacturing plant to derive operating characteristic curves. The paper also describes how these operating characteristic curves can be used to improve plant performance. [ABSTRACT FROM AUTHOR]

Replay attacks are often the most costly attacks to thwart when dealing with off-chip memory integrity. With a trusted System-on-Chip, the existing countermeasures against replay require a large amount of on-chip memory to provide tamper-proof storage for metadata such as hash values or nonces. Tree-based strategies can be deployed to reduce this unacceptable overhead; for example, the well-known Merkle tree technique decreases this overhead to a single hash value. However, it comes at the cost of performance-killing characteristics for embedded systems - e.g. non-parallelizable hash computations on tree updates. In this paper, we propose an alternative solution: the Tamper-Evident Counter Tree (TEC-Tree). It allows for tamper-evident off-chip storage of the nonces involved in a replay countermeasure; TEC-Tree parallelizes the computations involved in both the authentication and tree update processes. Moreover, because our tree relies on block encryption, it provides data confidentiality at no extra cost. TEC-Tree is a deployable solution for memory integrity, with low performance hit and hardware cost. [ABSTRACT FROM AUTHOR]

This paper discusses the state-of-the-art fast software implementation of block ciphers on Intel's new microprocessor Core2, particularly concentrating on "bitslice implementation". The bitslice parallel encryption technique, initially proposed by Biham for speeding-up DES, has been successful on RISC processors with many long registers, but on the other side bitsliced ciphers are not widely used in real applications on PC platforms, because in many cases they were actually not very fast on previous PC processors. Moreover the bitslice mode requires a non-standard data format and hence an additional format conversion is needed for compatibility with an existing parallel mode of operation, which was considered to be expensive. This paper demonstrates that some bitsliced ciphers have a remarkable performance gain on Intel's Core2 processor due to its enhanced SIMD architecture. We show that KASUMI, a UMTS/GSM mobile standard block cipher, can be four times faster when implemented using a bitslice technique on this processor. Also our bitsliced AES code runs at the speed of 9.2 cycles/byte, which is the performance record of AES ever made on a PC processor. Next we for the first time focus on how to optimize a conversion algorithm between a bitslice format and a standard format on a specific processor. As a result, the bitsliced AES code can be faster than a highly optimized "standard AES" code on Core2, even taking an overhead of the conversion into consideration. This means that in the CTR mode, bitsliced AES is not only fast but also fully compatible with an existing implementation and moreover secure against cache timing attacks, since a bitsliced cipher does not use any lookup tables with key/data-dependent address. [ABSTRACT FROM AUTHOR]

In this paper we design renewable traitor tracing scheme for anonymous attack. When pirated copies of some copyrighted content or content decrypting key are found, a traitor tracing scheme could identify at least one of the real users (traitors) who participate in the construction of the pirated content/key. When traitors are identified, the renewable scheme can revoke and exclude the decryption keys used by the traitors during piracy. Moreover, the revocation information included in the newly released content needs not only to disallow traitors to playback the new content, but also provide new tracing information for continuous tracing. This trace-revoke-trace system is the first such system for anonymous attack. It poses new challenges over the trace-revoke system that has extensively studied in the literatures for the pirate decoder attack. We hope the technologies described in this paper can shed new insights on future directions in this area for academia research. [ABSTRACT FROM AUTHOR]

The paper explores one of the graphical authentication techniques as the possible solution to the most important problems of traditional passwords. The aim of this work is to bring together the technical (cryptological) and non-technical (psychological) awareness into the research on passwords (click passwords in this case). Security issues of any authentication mechanism (relying on knowledge) should not be considered without analysis of the human factor − since the users' human nature was identified as a source of major weaknesses of conventional authentication. The paper deals with techniques which reduce password space and make passwords guesses feasible. Four types of pictures areas (of graphical interfaces) were investigated in order to bring to light common vulnerabilities − three of them were identified as types, which the graphical keypads should avoid. Statistics exposing strong tendentiousness in click passwords selection were presented as well. Furthermore, the paper presents a discussion on several issues of title authentication with regard to traditional passwords and other graphical techniques. [ABSTRACT FROM AUTHOR]

In this paper, we propose Cloak—a new class of reliable timing channels—which is fundamentally different from other timing channels in several aspects. First, Cloak encodes a message by a unique distribution of N packets over X TCP flows. The combinatorial nature of the encoding methods increases the channel capacity largely with (N,X). Second, Cloak offers ten different encoding and decoding methods, each of which has a unique tradeoff among several important considerations, such as channel capacity and the need for packet marking. Third, the packet transmissions modulated by Cloak could be carefully crafted to mimic the normal TCP flows in a typical TCP-based application session. Although Cloak's basic idea is simple, we show in this paper how we tackle a number of challenging issues systematically. Our experiment results collected from PlanetLab nodes and a test bed suggest that Cloak is feasible under various network conditions and different round-trip delays. [ABSTRACT FROM AUTHOR]

This paper describes an identification and authentication protocol for RFID tags with two contributions aiming at enhancing the security and privacy of RFID based systems. First, we assume that some of the servers storing the information related to the tags can be compromised. In order to protect the tags from potentially malicious servers, we devise a technique that makes RFID identification server-dependent, providing a different unique secret key shared by each pair of tag and server. The proposed solution requires the tag to store only a single secret key, regardless of the number of servers, thus fitting the constraints on tag's memory. Second, we provide a probabilistic tag identification scheme that requires the server to perform simple bitwise operations, thus speeding up the identification process. The proposed tag identification protocol assures privacy, mutual authentication and resilience to both DoS and replay attacks. Finally, each of the two schemes described in this paper can be independently implemented to enhance the security of existing RFID protocols. [ABSTRACT FROM AUTHOR]

Coordination artifacts play a primary role in cooperation and, in particular, active artifacts allow for the development of flexible cooperative software systems. Their role with respect to ubiquitous-computing environments can be defined, exploited, and assessed according to different perspectives. This paper presents a notion of active artifact that relies on the seminal definition given in CSCW literature by Schmidt and Simone, and it is applied to a model for systems supporting ubiquitous-computing collaborative environments (CASMAS). A technique to configure and interact with such environments, i.e., the composition of devices' functionalities according to their high-level features, and services provided, is presented. A scenario is used as an in-depth example along the paper. The architecture of a system implementing the scenario using our reference middleware is presented. [ABSTRACT FROM AUTHOR]

In this paper we present concepts for and experiences with a Situated Public Display system deployed in a university setting. We identify the rate with which information is updated as an important property to distinguish different kinds of information. With a first slideshow based prototype it was very difficult for users to predict whether information was updated since they last looked. To solve this problem, we took a broader view and conducted a contextual inquiry to investigate how people deal with paper based posters. We deduced an information flow diagram that identifies roles of people and categories of posters and noticeboards. We identified actionables, that is, posters that offer people to take a specific action, as a special type of information to support. We identified two strategies, planning and opportunism, to deal with actionable information. We present a system using two kinds of displays, News Displays and Reminder Displays, to support both strategies. We show how auctions can be used for Reminder Displays to select those information chunks that are most important in a particular context. Finally, we present an evaluation and lessons from the deployment. [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]

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]

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]

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]

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]