Service registration and discovery are functionalities central to any service-oriented architecture, and they are often provided by centralized entities in today's systems. However, there are advantages of scalability, robustness, as well as distribution of control and cost by further decentralization of these functionalities to all the participants in the system. Peer-to-peer networks are great enablers toward this goal as they are designed to be scalable and autonomic; redundancy and automatic reconfiguarion are built into these systems, enabling peers to form and maintain the network autonomously. This article describes a fully decentralized service directory infrastructure built on top of the peer-to-peer protocol Chord. Service registration is performed implicitly by embedding semantic information into the peer identifiers, grouping peers by service categories and forming islands on the ring topology. Service discovery is performed by sending queries and anycast messages to peers registered in the appropriate islands. The routing protocol is further modified to take advantage of the island topology, with reputation mechanism and multi-path routing implemented to avoid the threat of misbehaving peers dropping transit messages in the system. Simulations were performed to assess the efficacy of both the new routing scheme and misbehavior avoidance.

This paper presents a new technique for automatically synthesizing human walking motion. In the technique, a set of fundamental motion units called motion primitives is defined and each primitive is modeled statistically from motion capture data using a hidden semi-Markov model (HSMM), which is a hidden Markov model (HMM) with explicit state duration probability distributions. The mean parameter for the probability distribution function of HSMM is assumed to be given by a function of factors that control the walking pace and stride length, and a training algorithm, called factor adaptive training, is derived based on the EM algorithm. A parameter generation algorithm from motion primitive HSMMs with given control factors is also described. Experimental results for generating walking motion are presented when the walking pace and stride length are changed. The results show that the proposing technique can generate smooth and realistic motion, which are not included in the motion capture data, without the need for smoothing or interpolation.

This paper describes an approach to generating speech with emotional expressivity and speaking style variability. The approach is based on a speaking style and emotional expression modeling technique for HMM-based speech synthesis. We first model several representative styles, each of which is a speaking style and/or an emotional expression, in an HMM-based speech synthesis framework. Then, to generate synthetic speech with an intermediate style from representative ones, we synthesize speech from a model obtained by interpolating representative style models using a model interpolation technique. We assess the style interpolation technique with subjective evaluation tests using four representative styles, i.e., neutral, joyful, sad, and rough in read speech and synthesized speech from models obtained by interpolating models for all combinations of two styles. The results show that speech synthesized from the interpolated model has a style in between the two representative ones. Moreover, we can control the degree of expressivity for speaking styles or emotions in synthesized speech by changing the interpolation ratio in interpolation between neutral and other representative styles. We also show that we can achieve style morphing in speech synthesis, namely, changing style smoothly from one representative style to another by gradually changing the interpolation ratio.

In this paper, a semi-dynamic protection path configuration method is proposed for WDM optical networks. In the method, the protection path is established by connecting several sub-lightpaths from the source node to the destination node of the original working lightpath, as opposed to conventional path restoration method where a single protection lightpath between the source-destination pair performs restoration. The proposed method provides enhanced flexibility in protection path configuration and relieves the cost of spare capacity reservation. This paper also studies the effects of wavelength conversion capability of intermediate optical cross-connect nodes on protection path routing and spare capacity utilization. In terms of spare capacity utilization, the proposed method shows substantial reduction of spare capacity overhead compared with dedicated path restoration in all optical networks without wavelength conversion, and shows similar capacity efficiency compared with shared path restoration in opaque networks with full wavelength conversion capability. In terms of robustness, the proposed method shows nearly the same restoration ratio for double-link failure as that of dynamic restoration method.

This investigation proposes a fast wavelet-based color segmentation (FWCS) technique and a modified directional region-growing (DRG) technique for semantic image segmentation. The FWCS is a subsequent combination of progressive color truncation and histogram-based color extraction processes for segmenting color regions in images. By exploring specialized centroids of segmented fragments as initial growing seeds, the proposed DRG operates a directional 1-D region growing on pairs of color segmented regions based on those centroids. When the two examined regions are positively confirmed by DRG, the proposed framework subsequently computes the texture features extracted from these two regions to further check their relation using texture similarity testing (TST). If any pair of regions passes double checking with both DRG and TST, they are identified as associated regions. If two associated regions/areas are connective, they are unified to a union area enclosed by a single contour. On the contrary, the proposed framework merely acknowledges a linking relation between those associated regions/areas highlighted with any linking mark. Particularly, by the systematic integration of all proposed processes, the critical issue to decide the ending level of wavelet decomposition in various images can be efficiently solved in FWCS by a quasi-linear high-frequency analysis model newly proposed. The simulations conducted here demonstrate that the proposed segmentation framework can achieve a quasi-semantic segmentation without priori a high-level knowledge.

Suitably aggregated data burst enhances link utilization and reduces data processing complexity of optical transport networks rather than just transmitting each bursty input traffic from access networks. This data burst generation method is called as a burst assembly process and has two assembly parameters, timer and threshold, for regulating burst release time and burst size. Since the traffic characteristics of data burst generated at the burst assembler may affect network performance, the decision of burst assembly parameters should be carefully designed. Thus, in this paper we study the dimensioning burst assembly process to find the burst assembly parameter values satisfying target performance. For this purpose, we first analyze timer-based and threshold-based burst assembly processes, respectively. As constraints on the dimensioning burst assembly process, we consider the following performance metrics: 1) processing delay of control packet, 2) burst loss at control plane, and 3) link utilization. Based on these constraints, a decision mechanism of the burst assembly parameters is proposed. From numerical analysis, we suggest a possible lower boundary value for the burst assembly parameters satisfying the target burst loss rate and delay time at the control plane.

Particles several tens of nanometers in size were aligned in the desired positions in a controlled manner by using capillary force interaction and suspension flow. Latex beads 40-nm in diameter were aligned linearly around a 10-µm-hole template fabricated by lithography. Further control of their position and separation was realized using colloidal gold nanoparticles by controlling the particle-substrate and particle-particle interactions using an optical near field generated on the edge of a Si wedge, in which the separation of the colloidal gold nanoparticles was controlled by the direction of polarization.

We investigated the initial stage of Zn dot growth using near-field optical chemical vapor deposition. The dependence of the rate of Zn dot deposition on dot size revealed that the deposition rate was maximal when the dot grew to a size equivalent to the probe apex diameter. Such observed size-dependent resonance was in good agreement with theoretical results for dipole-dipole coupling with a Forster field between the deposited Zn dot and the probe apex.

This paper describes the characteristics of lithium-ion cells developed for stationary use, as in the case of stand-by sources in power systems. The effect of a cell-voltage-equalizing circuit developed for batteries of cells is also demonstrated. The tested lithium-ion cells were suitable to be charged by the constant-current, constant-voltage (CCCV) method and could be charged efficiently over a wide range of temperatures. They also showed good discharge performance with little dependence on the discharge current and temperature. Total capacity reduction of over 60% can be expected in batteries of lithium-ion cells. The cell-voltage-equalizing circuit was shown to be useful and necessary for batteries of lithium-ion cells in order to suppress deviations in the cell voltage and capacity loss.

Wireless Internet technologies have been developing and users are now able to access more information anywhere through small screen mobile devices. However, due to the limits of cost, bandwidth and screen size in a wireless environment, it is important to minimize interactions between a mobile user and his handheld device, as well as the amount of data transmitted. In this paper we present an interactive evolutionary approach for user-oriented Web search by using mobile devices. To verify this approach, a series of experiments has been conducted. The results show that our approach can allocate the information a user needs within only a few user-system interactions. It substantially reduces the number of retrieved pages a user has to visit. This is especially an important benefit to mobile users.

Modern telecom and signal relays have been optimized to carry and switch low signals and to withstand high dielectric strength. Recent designs have extremely small physical dimensions and are comparatively cheap. Small size and low cost also make this type of relay very attractive for industrial and automotive applications. For industrial and automotive applications performance characteristics other than low and stable contact resistance values are of importance. While, for industrial applications, safety aspects and inductive load switching characteristics are of major importance, in automotive applications, high switching currents, inductive and lamp loads and high ambient temperatures are essential. Tests were carried out in order to determine the limitations of small size relays. The results obtained clearly show the unexpectedly high load range which signal relays are able to cover. Despite their small size, these relays can handle switching loads up to several hundred volts and currents up to 5 A. On top of the high switching current there is high excess current capability, and relays can work at extreme ambient temperatures between -55 and more than +105 degrees C.

In an empowered Internet with end-to-end Quality of Service (QoS) facilities, it is essential for content servers to minimize reserved network resources to achieve a reduction in transmission cost for the use of QoS. Resource reservation usage charging forces customers to efficiently use network resources. In this paper, we analyze a model that optimizes the total cost when semi-elastic traffic flows are delivered in a client-server scenario. The client uses the proposed analytical model to easily control its buffer occupancy and to determine at any time if it is needed to utilize resource reservation or best-effort transmission mode.

In order to reduce the size of a wireless system, we propose a design theory for the broadband impedance matching circuit which connects an electrically small antenna (ESA) to a semiconductor amplifier. We confirmed its validity for the case of connection between a small slot loop antenna with a small radiation resistance of Ra =0.776 Ω and a semiconductor amplifier with high input impedance of ZL =321-j871 Ω with the aid of the simulations by the electrical circuits using transmission lines as well as the electromagnetic field (EM field) simulator. We also made experiments on this antenna with matching circuits using high temperature superconductor YBCO thin films on MgO substrates.

We propose a new call admission control (CAC) scheme for voice calls in cellular mobile communication networks. It is assumed that the rejection of a hand-off call is less desirable than that of a new call, for a hand-off call loss would cause a severe mental pain to a user. We consider the pains of rejecting new and hand-off calls as different costs. The key idea of our CAC is to restrict the admission of new calls in order to minimize the total expected costs per unit time over the long term. An optimal policy is derived from a semi-Markov decision process in which the intervals between successive decision epochs are exponentially distributed. Based on this optimal policy, we calculate the steady state probability for the number of established voice connections in a cell. We then evaluate the probability of blocking new calls and the probability of forced termination of hand-off calls. In the numerical experiments, it is found that the forced termination probability of hand-off calls is reduced significantly by our CAC scheme at the slight expense of the blocking probability of new calls and the channel utilization. Comparison with the static guard channel scheme is made.

We present a method of stabilizing a class of nonlinear systems which are not necessarily feedback linearizable. First, we show a new way of constructing a diffeomorphism to transform a class of nonlinear systems to the feedback linearized form with perturbation. Then, we propose a semi-globally stabilizing control law for nonlinear systems that are connected by a chain of integrator perturbed by arbitrary nonlinear terms. In our approach, we have flexibility in choosing a diffeomorphism where the system is not restricted to involutivity and this leads to reduction in computational burden and flexibility in controller design.

We demonstrated the transmission over 80 km at 10 Gb/s by using the amplifier and electroabsorption-modulator integrated laser diode. Tilt-facet antireflection window is implemented, inside of which a monitor photodiode is monolithically integrated for accurate power regulation. To better control the amplifier-input power and to reduce the feedback of the amplified spontaneous emission, an attenuator is incorporated by means of the inner-window. By amplifying the modulated signal and compensating modulator-chirp by gain-saturation in the amplifier, high power optical transmission is achieved from a device with -10 dB attenuation at total laser and amplifier currents of 200 mA.

We present and demonstrate a novel method of generating a π phase-alternated return-to-zero (RZ) signal together with pulse-amplitude equalization in a rational harmonic mode-locked fiber ring laser, by using a dual-drive Mach-Zehnder modulator. By adjusting the voltages applied to both arms of the modulator, amplitude-equalization and π phase shift can be achieved successfully at a 9.95 GHz repetition rate. The generated alternate-phase RZ signals show enhanced transmission performance in the single-mode fiber (SMF) links without dispersion compensation.

Web browsing task is based on depth-first searching scheme, so that searching relevant information from Web may be very tedious. In this paper, we propose personal browsing assistant system based on user intentions modeling. Before explicitly requested by a user, this system can analyze the prefetched resources from the hyperlinked Webpages and compare them with the estimated user intention, so that it can help him to make a better decision like which Webpage should be requested next. More important problem is the semantic heterogeneity between Web spaces. It makes the understandability of locally annotated resources more difficult. We apply semantic annotation, which is a transcoding procedure with the global ontology. Therefore, each local metadata can be semantically enriched, and efficiently comparable. As testing bed of our experiment, we organized three different online clothes stores whose images are annotated by semantically heterogeneous metadata. We simulated virtual customers navigating these cyberspaces. According to the predefined preferences of customer models, they conducted comparison-shopping. We have shown the reasonability of supporting the Web browsing, and its performance was evaluated as measuring the total size of browsed hyperspace.

In this paper, we propose a heuristic multicast routing algorithm, which minimizes the cost while satisfying both the wavelength required and hop length selection. The algorithm consists of two subproblems: the wavelength assignment & the routing path selection. For solving the wavelength assignment subproblem, an auxiliary graph is created where by the nodes and the links in the original network are transformed to the edges and the vertices, respectively, and the same availability wavelength of each edge is taken into a multicast group. Furthermore, for solving the routing path selection subproblem, the shortest-path routing strategy is adopted to choose transmission path between two multicast groups. Simulation results show that our algorithm performs much better than previously proposed algorithms with increasing call-connection probability by 28% and reducing the blocking probability by 52%.

In this paper, we generalize the theory of a convex set relaxation for the maximum weight stable set problem due to Grotschel, Lovasz and Schrijver to the generalized stable set problem. We define a convex set which serves as a relaxation problem, and show that optimizing a linear function over the set can be done in polynomial time. This implies that the generalized stable set problem for perfect bidirected graphs is polynomial time solvable. Moreover, we prove that the convex set is a polytope if and only if the corresponding bidirected graph is perfect. The definition of the convex set is based on a semidefinite programming relaxation of Lovasz and Schrijver for the maximum weight stable set problem, and the equivalent representation using infinitely many convex quadratic inequalities proposed by Fujie and Kojima is particularly important for our proof.