We explain how network failures were caused by a natural disaster, describe the restoration steps that were taken, and present lessons learned from the recovery. At 21:26 on December 26th (UTC+9), 2006, there was a serious undersea earthquake off the coast of Taiwan, which measured 7.1 on the Richter scale. This earthquake caused significant damage to submarine cable systems. The resulting fiber cable failures shut down communications in several countries in the Asia Pacific networks. In the first post-earthquake recovery step, BGP routers detoured traffic along redundant backup paths, which provided poor quality connection. Subsequently, operators engineered traffic to improve the quality of recovered communication. To avoid filling narrow-bandwidth links with detoured traffic, the operators had to change the BGP routing policy. Despite the routing-level first aid, a few institutions could not be directly connected to the R&E network community because they had only a single link to the network. For these single-link networks, the commodity link was temporarily used for connectivity. Then, cable connection configurations at the switches were changed to provide high bandwidth and next-generation Internet service. From the whole restoration procedure, we learned that redundant BGP routing information is useful for recovering connectivity but not for providing available bandwidth for the re-routed traffic load and that collaboration between operators is valuable in solving traffic engineering issues such as poor-quality re-routing and lost connections of single-link networks.

Recently, technology roadmaps have been actively constructed by various organizations such as governments, industry segments, academic societies and companies [1]. While the common basic purpose of these roadmaps is sharing common recognition of the technology among stakeholders, there exists a specific role for each organization. One of the important roles of academic societies is to show the directions in which society is moving. The IEICE technical group on Concurrent System Technology (CST) established in 1993 stands at a turning point and needs to move forward in new directions after more than a decade of activities and contributions. However, neither top-down (market-pull/requirements-pull) nor bottom-up (technology-push) roadmapping is suitable for CST because CST is a kind of systems engineering. This paper proposes a new technology roadmapping methodology (middle-up-down technology roadmapping) for systems engineering and shows three future directions of CST and one roadmap for service systems that integrate CST and services science.

This paper investigates two issues of cellular engineering for cellular systems enhanced with two-hop fixed relay nodes (FRNs): spectrum partitioning and relay positioning, under the assumption of frequency reuse distance being equal to one. A channel-dependent spectrum partitioning scheme is proposed. According to this scheme, the ensemble mean of signal-to-interference-ratio on respective sets of links are taken into account to determine the bandwidths assigned to links connecting base station (BS) and FRNs, those connecting FRNs and mobile terminals (MTs) and those connecting BS and MTs. The proper FRN positioning is formulated as a constraint optimization problem, which tries to maximize the mean user data rate while at the same time ensures in probability 95% users being better served than in conventional cellular systems without relaying. It is demonstrated with computer simulations that FRN positioning has a strong impact on system performance. In addition, when FRNs can communicate with BS over line-of-sight channels the FRN enhanced cellular system with our proposed spectrum partitioning can remarkably outperform that with a known channel-borrowing based scheme and the conventional cellular systems without relaying. Simulation results also show that with proper FRN positioning the proposed spectrum partitioning scheme is robust against the unreliability of links connecting BS and FRNs.

This study initiates a systematic evaluation of web search engine performance using queries written in Thai. Statistical testing indicates that there are some significant differences in the performance of search engines. In addition to compare the search performance, an analysis of the returned results is carried out. The analysis of the returned results shows that the majority of returned results are unique to a particular search engine and each system provides quite different results. This encourages the use of metasearch techniques to combine the search results in order to improve the performance and reliability in finding relevant documents. We examine several metasearch models based on the Borda count and Condorcet voting schemes. We also propose the use of Evolutionary Programming (EP) to optimize weight vectors used by the voting algorithms. The results show that the use of metasearch approaches produces superior performance compared to any single search engine on Thai queries.

Several approaches have been studied to cope with the exceptional features of non-segmented languages. When there is no explicit information about the boundary of a word, segmenting an input text is a formidable task in language processing. Not only the contemporary word list, but also usages of the words have to be maintained to cover the use in the current texts. The accuracy and efficiency in higher processing do heavily rely on this word boundary identification task. In this paper, we introduce some statistical based approaches to tackle the problem due to the ambiguity in word segmentation. The word boundary identification problem is then defined as a part of others for performing the unified language processing in total. To exhibit the ability in conducting the unified language processing, we selectively study the tasks of language identification, word extraction, and dictionary-less search engine.

Web services (WS, hereafter) paradigm has attained such a relevance in both the academic and the industry world that the vision of the Internet has evolved from being considered as a mere repository of data to become the underlying infrastructure on which organizations' strategic business operations are being deployed [1]. Security is a key aspect if WS are to be generally accepted and adopted. In fact, over the past years, the most important consortiums of the Internet, like IETF, W3C or OASIS, have produced a huge number of WS-based security standards. Despite this spectacular growth, a development process that facilitates the systematic integration of security into all subprocesses of WS-based software development life-cycle does not exist. Eventually, this process should guide WS-based software developers in the specification of WS-based security requirements, the design of WS-based security architectures, and the deployment of the most suitable WS security standards. In this article, we will briefly present a process of this type, named PWSSec (Process for Web Services Security), and the artifacts used during the elicitation activity, which belongs to the subprocess WSSecReq aimed at producing a WS-based security requirement specification.

The specification of a Multi-Agent System (MAS) involves the identification of a large number of entities and their relationships. This is a non-trivial task that requires managing different views of the system. Many problems concerning this issue originate in the presence of contradictory goals and tasks, inconsistencies, and unexpected behaviours. Such troublesome configurations should be detected and prevented during the development process in order to study alternative ways to cope with them. In this paper, we present methods and tools that support the management of contradictions during the analysis and design of MAS. Contradiction management in MAS has to consider both individual (i.e. agent) and social (i.e. organization) aspects, and their dynamics. Such issues have already been considered in social sciences, and more concretely in the Activity Theory, a social framework for the study of interactions in activity systems. Our approach applies knowledge from Activity Theory in MAS, especially its base of contradiction patterns. That requires a formalization of this social theory in order to be applicable in a software engineering context and its adaptation to agent-oriented methodologies. Then, it will be possible to check the occurrence of contradiction patterns in a MAS specification and provide solutions to those situations. This technique has been validated by implementing an assistant for the INGENIAS Development Kit and has been tested with several case studies. This paper shows part of one of these experiments for a web application.

This paper reports an efficient Discrete Cosine Transform (DCT) processing method for images using a massive-parallel memory-embedded SIMD matrix processor. The matrix-processing engine has 2,048 2-bit processing elements, which are connected by a flexible switching network, and supports 2-bit 2,048-way bit-serial and word-parallel operations with a single command. For compatibility with this matrix-processing architecture, the conventional DCT algorithm has been improved in arithmetic order and the vertical/horizontal-space 1 Dimensional (1D)-DCT processing has been further developed. Evaluation results of the matrix-engine-based DCT processing show that the necessary clock cycles per image block can be reduced by 87% in comprison to a conventional DSP architecture. The determined performances in MOPS and MOPS/mm2 are factors 8 and 5.6 better than with a conventional DSP, respectively.

We survey traffic matrix models, whose elements represent the traffic demand between source-destination pair nodes. Modeling the traffic matrix is useful for multilayer Traffic Engineering (TE) in IP optical networks. Multilayer TE techniques make the network so designed flexible and reliable. This is because it allows reconfiguration of the virtual network topology (VNT), which consists of a set of several lower-layer (optical) paths and is provided to the higher layer, in response to fluctuations (diurnal) in traffic demand. It is, therefore, important to synthetically generate traffic matrices as close to the real ones as possible to maximize the performance of multilayer TE. We compare several models and clarify their applicability to VNT design and control. We find that it is difficult in practice to make an accurate traffic matrix with conventional schemes because of the high cost for data measurement and the complicated calculations involved. To overcome these problems, we newly introduce a simplified traffic matrix model that is practical; it well mirrors real networks. Next, this paper presents our developed server, the IP Optical TE server. It performs multilayer TE in IP optical networks. We evaluate the effectiveness of multilayer TE using our developed IP Optical server and the simplified traffic matrix. We confirm that multilayer TE offers significant CAPEX savings. Similarly, we demonstrate basic traffic control in IP optical networks, and confirm the dynamic control of the network and the feasibility of the IP Optical TE server.

One approach to accommodating IP traffic on a wavelength division multiplexing (WDM) network is to construct a logical topology, establishing a set of lightpaths between nodes. The lightpaths carry IP traffic but do not require any electronic packet processing at intermediate nodes, thereby reducing the load on those nodes. When the IP and WDM networks have independent routing functions, however, the lightpaths in the WDM network may not be fully utilized by the IP router. It is therefore necessary to integrate the two routing mechanisms in order to utilize resources efficiently and adapt to changes in traffic. In this paper, we propose an integrated routing mechanism for IP over WDM networks. The key idea is to first prepare a set of virtual-links representing the lightpaths that can be established by the WDM network, then calculate the minimum cost route on an IP network including those links. Our simulation results show that when traffic patterns do not change, the throughput of our method is almost the same as that of a logical topology optimally designed for a given traffic demand. When traffic patterns change, the throughput of our method is about 50% higher than that of the logical topology.

In this paper we focus on building a large scale keyword search service over structured Peer-to-Peer (P2P) networks. Current state-of-the-art keyword search approaches for structured P2P systems are based on inverted list intersection. However, the biggest challenge in those approaches is that when the indices are distributed over peers, a simple query may cause a large amount of data to be transmitted over the network. We propose in this paper a new P2P keyword search scheme, called "Proof," which aims to reduce the network traffic generated during the intersection process. We applied three main ideas in Proof to reduce network traffic, including (1) using a sorted query flow, (2) storing content summaries in the inverted lists, and (3) setting a stop condition for the checking of content summaries. We also discuss the advantages and limitations of Proof, and conducted extensive experiments to evaluate the search performance and the quality of search results. Our simulation results showed that, compared with previous solutions, Proof can dramatically reduce network traffic while providing 100% precision and high recall of search results, at some additional storage overhead.

Multipath routing employs multiple parallel paths between the source and destination for a connection request to improve resource utilization of a network. In this paper, we present an integrated design of multipath routing with delay constraints and failure survivability in MPLS networks. By combining the failure survivability schemes into the multipath routing algorithms, path protection or restoration policies will enable the network to accommodate link failures and at the same time achieve significant improvement on network resource utilization. We propose a number of multipath routing algorithms, working-backup path selection and bandwidth allocation schemes. We evaluate the performance of the proposed schemes in terms of call blocking probability, network resource utilization and load balancing factor. Extensive simulation results validate the effectiveness of the proposed schemes. In particular, we compare these multipath schemes to the existing failure recovery schemes that mostly focus on single path routing. The results demonstrate that the proposed integrated design framework can provide effective network failure survivability, and also achieve better load balancing and/or higher network resource utilization.

Accurate estimating or measuring the intake manifold absolute pressure plays an important role in automobile engine control. In order to achieve the real-time estimation of the absolute pressure, the high accuracy and high speed processing ability are required for automobile engine control systems. Therefore, in this paper, an analog method is discussed and a fully integrated analog circuit is proposed to simulate automobile intake systems. Furthermore, a novel behavioral macromodeling is proposed for the analog circuit design. With the analog circuit, the intake manifold absolute pressure, which plays an important role for the effective automobile engine control, can be accurately estimated or measured in real time.

Research has been actively proposed into how to specify requirements in the upper stream of software development. For example, the main research issues regarding Structured Analysis and Object Oriented Analysis methodologies include requirements elicitation, modeling, and validation of specifications to give a starting point for software development. At the same time, another area of research has emerged that recognizes the importance of guaranteeing requirements quality by goals. As the impact of IT penetrates to mobile devices, information appliances and automobiles, goal oriented requirements engineering (GORE) approaches for performance and safety in embedded systems have been proposed. Non-Functional Requirements (NFRs) such as business strategy, security and privacy, are now being formalized by Requirements Engineering (RE) technologies, because enterprise business is now heavily influenced by IT, for example in e-Business. As IT is fast becoming ubiquitous in society, the importance of Goal Orientation will increase as socio-technology enables visualization of the role of software in social systems. In this paper, we discuss the current states and trends of GORE from the viewpoints of both academia and industry.

Virtual Private Networks (VPNs) are overlay networks established on top of a public network backbone with the goal of providing a service comparable to Private Networks (PNs). The recently proposed VPN hose-model provides customers with flexible and convenient ways to specify their bandwidth requirements. To meet the specified bandwidth requirements, the Network Service Provider (NSP) must reserve sufficient bandwidth on the data transmission paths between each pair of endpoints in a VPN. In addition, the reliability of a VPN depends on the reliability of the data transmission paths. Italiano et al. proposed an algorithm that finds a set of backup paths for a given VPN (VPN tree) under the single-link failure model [1]. When a link failure is detected on a VPN tree, a backup path corresponding to the failed link can be activated to restore the disconnected VPN tree into a new one, thereby ensuring the reliability of the VPN. However, Italiano's algorithm cannot guarantee that the specified bandwidth requirement of the given VPN under the single-link failure model will be met. To address this issue, we propose a new backup path set selection algorithm called BANGUAD in this paper. In addition, the problem of establishing multiple bandwidth-guaranteed hose-model VPNs under the single-link failure model has not been investigated previously. However in this problem, bandwidth-sharing algorithms have the potential to improve the performance of a provisioning algorithm significantly. Therefore, we also propose a bandwidth sharing algorithm and three provisioning algorithms for establishing multiple bandwidth-guaranteed hose-model VPNs under the single-link failure model. Simulations that compare the performance of the proposed algorithms are reported.

This paper shows that the Surrounding Gate Transistor (SGT) can be scaled down to decananometer gate lengths by using an intrinsically-doped body and gate work function engineering. Strong gate controllability is an essential characteristics of the SGT. However, by using an intrinsically-doped body, the SGT can realize a higher carrier mobility and stronger gate controllability of the silicon body. Then, in order to adjust the threshold voltage, it is necessary to adopt gate work function engineering in which a metal or metal silicide gate is used. Using a three-dimensional (3D) device simulator, we analyze the short-channel effects and current characteristics of the SGT. We compare the device characteristics of the SGT to those of the Tri-gate transistor and Double-Gate (DG) MOSFET. When the silicon pillar diameter (or silicon body thickness) is 10 nm, the gate length is 20 nm, and the oxide thickness is 1 nm, the SGT shows a subthreshold swing of 63 mV/dec and a DIBL of -17 mV, whereas the Tri-gate transistor and the DG MOSFET show a subthreshold swing of 71 mV/dec and 77 mV/dec, respectively, and a DIBL of -47 mV and -75 mV, respectively. By adjusting the value of the gate work function, we define the off current at VG = 0 V and VD = 1 V. When the off current is set at 1 pA/µm, the SGT can realize a high on current of 1020 µA/µm at VG = 1 V and VD = 1 V. Moreover, the on current of the SGT is 21% larger than that of the Tri-gate transistor and 52% larger than that of the DG MOSFET. Therefore, the SGT can be scaled reliably toward the decananometer gate length for high-speed and low-power ULSI.

The Goal-Orientation is one of the key features in agent systems. This paper proposes a new methodology for multi-agent system development based on Goal Net model. The methodology covers the whole life cycle of the agent system development, from requirement analysis, architecture design, detailed design to implementation. A Multi-Agent Development Environment (MADE) that facilitates the design and implementation of agent systems is presented. A case study on an agent-based e-learning system developed using the proposed methodology is illustrated in this paper.

This paper describes a novel engineering change order (ECO) design method for large-scale, high performance LSIs, based on a patchwork-like partitioning technique. In conventional design methods, even when only small changes are made to the design after the placement and routing process, a whole re-layout must be done, and this is very time consuming. Using the proposed method, we can partition the design into several parts after logic synthesis. When design changes occur in HDL, only the parts related to the changes need to be redesigned. The netlist for the changed design remains almost the same as the original, except for the small changed parts. For partitioning, we used multiple-fan-out-points as partition borders. An experimental evaluation of our method showed that when a small change was made in the RTL description, the revised circuit part had only about 87 gates on average. This greatly reduces the re-layout time required for implementing an ECO. In actual commercial designs in which several design changes are required, it takes only one day to redesign.

This paper proposes a Generalized Traffic Engineering Protocol (GTEP). GTEP is a protocol that permits communication between a Path Computation Element (PCE) and a Generalized Multi-Protocol Label Switching (GMPLS) controller (CNTL). The latter is hosted by each GMPLS node; it handles GMPLS and MPLS protocols such as routing and signaling protocols as well as controlling the GMPLS node host. The PCE provides multi-layer traffic engineering; it calculates Label Switched Path (LSP) routes and judges whether a new lower-layer LSP should be established. GTEP functions are implemented in both the PCE and GMPLS router. We demonstrate a multi-layer traffic engineering experiment conducted with GTEP.

The increasing complexity and shorter life cycle of software have made it necessary to reuse software. Object-oriented development has not facilitated extensive reuse of software and it has become difficult to manage and understand modern object-oriented systems which have become very extensive and complex. However, components, compared with objects, provide more advanced means of structuring, describing and developing systems, because they are more coarse grained and have more domain-specific aspects than objects. In addition, they are also suited to a current distributed environment due to their reusability, maintainability and granularity. In this paper, we present a process of extracting components from object-oriented systems. We define some static metrics and guidelines that can be applied to transform object-oriented systems into component-based systems. Our process consists of two parts. First, basic components are created based on composition and inheritance relationships between classes. Second, the intermediate system is refined into a component-based system with our proposed static metrics and guidelines.