The (cinema) caption processing that adds descriptive text on a sequence of frames is an important video manipulation function that a video editor should support. This paper proposes an efficient MC-DCT compressed domain approach to insert the caption into the MPEG compressed video stream. It basically adds the DCT blocks of the caption image to the corresponding DCT blocks of the input frames one by one in the MC-DCT domain as in [6]. However, the strength of the caption image is adjusted in the DCT domain to prevent the resulting DCT coefficients from exceeding the maximum value allowed in MPEG. In order to adjust the strength of the caption image adaptively we need to know the exact pixel value of the input image. This is a difficult task in DCT domain. We propose an approximation scheme for the pixel values in which the DC value of a block is used as the expected pixel value for all pixels in that block. Although this approximation may lead to some errors in the caption area, it still provides a relatively high image quality in the non-caption area, whereas the processing time is about 4.9 times faster than the decode-captioning-reencode method.

Layering architecture of the Internet Protocol provides independent processing for each layer by concealing state information from each layer. Application Program Interface (API) is based on the idea of layering model. However, the idea disturbs efficient processing of applications requiring adaptation to network environment, such as context-aware applications in mobile computing. To address this need, this paper proposes MIBsocket designed as an integrated control and management system for general network information. Any variable information related to network is shared between each applications and operating system. MIBsocket detects and informs changes in network resources to applications. MIBsocket functions such as Get, Set, and Trap used in the application adapts dynamically to any environments. MIBsocket provides portability and facility for applications: it only requires a few modification to the operating system and its API has the same programmable interfaces as usual API's. MIBsocket does not interfere the current layering architecture, but it achieves remarkable improvement on the current model. We have measured costs of MIBsocket, and applied MIBsocket to the application named interface switching system which enables a mobile host to connect to the Internet anytime by switching interface depending on network environment. As a result, the costs of MIBsocket was found acceptable. The application shows that MIBsocket is useful for movement detection and reconfiguration of network resources in the mobile computing.

Linear adaptive digital filters are applied to various fields for their simplicity in the design and implementation. Considering many kinds of nonlinearities inherent in practical systems, however, nonlinear adaptive filtering will be more desirable. This paper presents a design method for multi-input single-output nonlinear adaptive digital filters using recurrent neural networks. Furthermore, in comparison with this method and the method based on the conventional linear theory, if the proposed method is used, better results can be obtained, and, it is possible that the learning efficiency is improved, because the parallel learning is carried out in this method. Finally, the results of computer simulation are presented to illustrate the effectiveness of the proposed method.

In this paper, a novel adaptive digital watermarking approach based upon human visual system model and fuzzy clustering technique is proposed. The human visual system model is utilized to guarantee that the watermarked image is imperceptible. The fuzzy clustering approach has been employed to obtain the different strength of watermark by the local characters of image. In our experiments, this scheme allows us to provide a more robust and transparent watermark.

This paper presents a digital reaction-diffusion system (DRDS)--a model of a discrete-time discrete-space reaction-diffusion dynamical system--for designing new image processing algorithms inspired by biological pattern formation phenomena. The original idea is based on the Turing's model of pattern formation which is widely known in mathematical biology. We first show that the Turing's morphogenesis can be understood by analyzing the pattern forming property of the DRDS within the framework of multidimensional digital signal processing theory. This paper also describes the design of an adaptive DRDS for image processing tasks, such as enhancement and restoration of fingerprint images.

This paper presents a method of MRAC (model reference adaptive control) for MIMO (multi-input multi-output) nonlinear systems using NNs (neural networks). The control input is given by the sum of the output of a model reference adaptive controller and the output of the NN (neural network). The NN is used to compensate the nonlinearity of plant dynamics that is not taken into consideration in the usual MRAC. The role of the NN is to construct a linearized model by minimizing the output error caused by nonlinearities in the control systems.

The formulation of the process of analog system design has been done on the basis of the control theory application. This approach generalizes the design process and produces different design trajectories inside the same optimization procedure. The problem of the optimal design algorithm construction is defined as the minimal-time problem of the control theory. The main equations for the proposed design methodology were elaborated. These equations include the special control functions that are introduced artificially to generalize the design problem. Optimal dependencies of the control functions give the possibility to reduce the total computer design time. This idea was tested with different optimization algorithms of the design process. Numerical results of some simple electronic circuit design demonstrate the efficiency of the proposed approach. These examples show that the traditional design strategy is not time-optimal and the potential computer time gain of the optimal design strategy increases when the size and complexity of the system increase.

This paper explores how to extend the dependency pair technique for proving termination of higher-order rewrite systems. We show that the termination property of higher-order rewrite systems can be checked by the non-existence of an infinite R-chain, which is an extension of Arts' and Giesl's result for the first-order case. It is clarified that the subterm property of the quasi-ordering, used for proving termination automatically, is indispensable.

This paper proposes a measure of coefficient quantization errors for linear discrete-time state-space systems. The proposed measure of state-space systems agrees with the actual output error variance since it is derived from the exact evaluation of the output error variance due to coefficient deviation. The measure in this paper is represented by the controllability and the observability gramians and the state covariance matrix of the system. When the variance of coefficient variations is very small, the proposed measure is identical to the conventional statistical sensitivity of state-space systems. This paper also proposes a method of synthesizing minimum measure structures. Numerical examples show that the proposed measure is in very good agreement with the actual output error variance, and that minimum measure structures have a very small degradation of the frequency characteristic due to coefficient quantization.

CRL (Communications Research Laboratory, Independent Administrative Institution Japan) is developing a road to vehicle multiple-service communication system based on RoF (Radio over Fiber) technology in a millimeter-wave frequency region of 36-37 GHz. In the experimental system, vehicle can receive three wireless services such as PHS (Personal Handy-phone System), ETC (Electronic Toll Collection system), SB (Satellite Broadcasting). In this paper, the system concept and experimental system configuration are introduced. Furthermore, SDR (Software Defined Radio) mobile terminal technology is mentioned and a new concept for a next generation mobile communication network system based on RoF is proposed.

This paper provides a new robust guaranteed cost controller design method for discrete parameter uncertain time delay systems. The result shows much tighter bound of guaranteed cost than that of existing paper. In order to get the optimal (minimum) value of guaranteed cost, an optimization problem is given by linear matrix inequality (LMI) technique. Also, the parameter uncertain systems with time delays in both state and control input are considered.

In two- or more-dimensional systems where the components of the sample data are strongly correlated, it is not proper to divide the input space into several subspaces without considering the correlation. In this paper, we propose the usage of the method of principal component in order to uncorrelate and remove any redundancy from the input space of the adaptive neuro-fuzzy inference system (ANFIS). This leads to an effective partition of the input space to the fuzzy model and significantly reduces the modeling error. A computer simulation for two frequently used benchmark problems shows that ANFIS with the uncorrelation process performs better than the original ANFIS under the same conditions.

An uplink synchronised CDMA system through transmission timing control at mobile users has been proposed to improve the uplink capacity. This Letter mathematically investigates its capacity, considering perfect fast TPC and two antenna diversity reception in a single cell environment and compares it with that of a conventional CDMA system.

This letter focuses on the design of a unified estimator for scheduled control in nonlinear systems with unknown parameter. An estimation law with a finite convergence time is formulated to compute the unknown scheduling parameter that drives a scheduled controller. This estimator can also be extended to the types of scheduled controllers addressed in the literature.

A model of interactive videoconference is proposed for investigating the interactivity of the videoconference. Through running a prototype videoconferencing system over ATM networks, we observed that the system stability would degrade abruptly if the interaction demand from conferees exceeds what the system control can support. By using the proposed model, we formulate the problem of achieving high interactivity and stability as maximizing interactivity by tuning system parameters subject to some stability constraints. Solving the problem is non-trivial since it involves unpredictable network delays. We thus develop practical approaches that can choose and dynamically adjust, according to the network condition, the values of system parameters to meet the stability constraints and improve the interactivity. Finally, we validate our approaches and provide guidelines on choosing the parameter values by conducting experiments and simulations.

This paper discusses the teletraffic characteristics of cellular systems using Dynamic Channel Assignment. In general, it is difficult to exactly and theoretically analyze the teletraffic characteristics of Dynamic Channel Assignment. Also, it is not easy to theoretically evaluate influence of mobility on the traffic characteristics. This paper proposes approximate techniques to analyze teletraffic characteristics of Dynamic Channel Assignment considering mobility. The proposed techniques are based on Clique Packing approximation.

This paper proposes a novel adaptive array configuration that reduces high-power co-channel interference (CCI) by utilizing the difference in arrival times between CCI and the desired signal in asynchronous TDD systems. The proposed adaptive array extracts only the CCI and employs pre-null steering for only the CCI by utilizing the fact that only the CCI arrives during the guard time in asynchronous TDD systems. Since the proposed adaptive array enables us to apply the Minimum Mean Square Error (MMSE) algorithm through synchronization with the desired signal using the output signal obtained by pre-null steering, high quality transmission can be achieved even in the presence of high-power CCI. Moreover, based on measurements using a fading simulator and field data, an adaptive array testbed exemplifying the proposed configuration is presented to show the reduction in the high-power CCI.

In this paper, we present a dynamic output feedback controller design technique for robust decentralized stabilization of uncertain large-scale systems with time-delay in the subsystem interconnections. Based on Lyapunov second method, a sufficient condition for the stability, is derived in terms of three linear matrix inequalities (LMI). The solutions of the LMIs can be easily obtained using efficient convex optimization techniques. A numerical example is given to illustrate the proposed method.

A knowledge gap between network operators and system developers in Network Management System (NMS) construction has widened. This has been caused by an expansion of supported business processes and increasingly sophisticated network management functions. This gap makes system development costly and time consuming. Function development, led by operators, is a promising solution to the problems caused by the gap. This type of development should not require an operator to know how to develop NMS. Standard objects may be used to meet this requirement and save time and the cost of NMS construction. However, they are not sufficient to design functions supporting some tasks that are for providing custom services. In this paper, we propose a partial extension package, composed of several object classes. This package is attached to the standard objects to design a custom function. Information processing in a new function can be added, and easily modified, using this package. This package specifies states that invoke the information processing. It also includes objects that add new data without changing standard objects. It makes use of several design patterns in order to weaken coupling to the standard objects. We have applied this package to two programs. One plans maintenance tasks schedules, the other sets threshold values for quality of service. We made use of software metrics to measure their performance in terms of flexibility. The results show that the proposed package continues to make it possible to reuse the standard objects, and makes it easy to modify the behavior of a new function.

Stand-alone photovoltaic (PV) power systems are potential power sources for telecommunications equipment especially equipment installed outdoors. To be practical, they must have a high conversion efficiency and a long lifetime. We have proposed a stand-alone photovoltaic power system that uses electric double-layer capacitors (EDLCs) and lead acid batteries as power storage devices. This system smooths out the fluctuations in power generated by the PV array by using the EDLC's charge-and-discharge power; this reduces the number of battery charge-and-discharge cycles. We simulated the system's operating characteristics and evaluated the photovoltaic array mismatching loss, system conversion loss, battery contribution factor, averaged battery state-of-charging, and maximum depth-of-discharging. The results show that the system is effective at reducing the mismatching loss and battery contribution factor, so the system efficiency is expected to be improved by using high conversion efficiency DC-DC converters. Moreover the system can maintain the averaged battery state-of-charging during operation. This indicates that smaller batteries can be used. The maximum depth-of-discharging can be kept lower than in the conventional system. Consequently, the proposed system should have a longer battery lifetime.