In this paper, we present a flexible distributed computing system in which it is very easy to add required computing components at any time. The system is an Internet-based solution, and mainly developed by Java and XML. Moreover, by implementing a new configuration of computing information that is setting up Public Information and Private Information, the system can accommodate various computing requests, and facilitate a flexible design. Additionally, to show the practical merit, as an example of signal processing, we presented how to apply our proposed system to selection of a suitable artificial neural network.

Self-stabilization is a theoretical framework of non-masking fault-tolerant distributed algorithms. In this paper, we investigate the Steiner tree problem in distributed systems, and propose a self-stabilizing heuristic solution to the problem. Our algorithm is constructed by four layered modules (sub-algorithms): construction of a shortest path forest, transformation of the network, construction of a minimum spanning tree, and pruning unnecessary links and processes. Competitiveness is 2(1-1/l), where l is the number of leaves of optimal solution.

Simply-typed term rewriting systems (STRSs) are an extension of term rewriting systems. STRSs can be naturally handle higher order functions, which are widely used in existing functional programming languages. In this paper we design recursive and lexicographic path orders, which can efficiently prove the termination of STRSs. Moreover we discuss an application to the dependency pair and the argument filtering methods, which are very effective and efficient support methods for proving termination.

In this paper, we propose a new counting scheme for m n contingency tables. Our scheme is a modification of Dyer and Greenhill's scheme for two rowed contingency tables. We can estimate not only the sizes of error, but also the sizes of the bias of the number of tables obtained by our scheme, on the assumption that we have an approximate sampler.

Concurrency in the computing systems using a deadlock avoidance strategy varies largely according to the way that resource usage plan of process is used in testing the possibility of deadlocks. If a detailed resource usage plan of process is to be taken into account, the deadlock avoidance problem is known to be NP-complete. A decomposition model to manage resources is proposed, where process is logically partitioned into a number of segments each of which uses at least one resource. It is shown that one of our deadlock avoidance algorithms achieves the best concurrency among the polynomial-bounded algorithms. We also present a heuristic algorithm that achieves concurrency close to the optimal one. Finally, we analyze concurrency of various algorithms.

Group multicasting is a generalization of multicasting whereby every member of a group is allowed to multicast messages to other members that belongs to the same group. The group multicast routing problem (GMRP) is that of finding a set of multicast trees with bandwidth requirements, each rooted at a member of the group, for multicasting messages to other members of the group. An optimal solution to GMRP is a set of trees, one for each member of the group, that incurs the least overall cost. This problem is known to be NP-complete and hence heuristic algorithms are likely to be the only viable approach for computing near optimal solutions in practice. In this paper, we derive a lower bound on the cost of an optimal solution to GMRP by using Lagrangean Relaxation and Subgradient Optimization. This lower bound is used to evaluate the two existing heuristic algorithms in terms of their ability to find close-to-optimal solutions.

This paper presents a novel wavelet compression technique to increase compression of images. Based on zerotree entropy coding method, this technique initially uses only two symbols (significant and zerotree) to compress image data for each level. Additionally, sign bit is used for newly significant coefficients to indicate them being positive or negative. Contrary to isolated zero symbols used in conventional zerotree algorithms, the proposed algorithm changes them to significant coefficients and saves its location, they are then treated just like other significant coefficients. This is done to decrease number of symbols and hence, decrease number of bits to represent the symbols used. In the end, algorithm indicates isolated zero coordinates that are used to change the value back to original during reconstruction. Noticeably high compression ratio is achieved for most of the images, without changing image quality.

In this paper, we propose a new method of automatic speech summarization for each utterance, where a set of words that maximizes a summarization score is extracted from automatic speech transcriptions. The summarization score indicates the appropriateness of summarized sentences. This extraction is achieved by using a dynamic programming technique according to a target summarization ratio. This ratio is the number of characters/words in the summarized sentence divided by the number of characters/words in the original sentence. The extracted set of words is then connected to build a summarized sentence. The summarization score consists of a word significance measure, linguistic likelihood, and a confidence measure. This paper also proposes a new method of measuring summarization accuracy based on a word network expressing manual summarization results. The summarization accuracy of each automatic summarization is calculated by comparing it with the most similar word string in the network. Japanese broadcast-news speech, transcribed using a large-vocabulary continuous-speech recognition (LVCSR) system, is summarized and evaluated using our proposed method with 20, 40, 60, 70 and 80% summarization ratios. Experimental results reveal that the proposed method can effectively extract relatively important information by removing redundant or irrelevant information.

A mobile ad hoc network (MANET) is characterized by multi-hop wireless links in the absence of any cellular infrastructure as well as by frequent host mobility. This paper proposes a SMPQ: Spiral-Multi-Path QoS routing protocol in a MANET, while the MAC sub-layer adopts the CDMA-over-TDMA channel model. This work investigates the bandwidth reservation problem of on-demand QoS routing in a wireless mobile ad-hoc network. The proposed approach increases the ability of a route to identify a robust path, namely a spiral-multi-path, from source host to destination host, in a MANET to satisfy certain bandwidth requirements. Two important contributions of the proposed spiral-multi-path are: (1) the spiral-multi-path strengthens route-robustness and route-stability properties and (2) the spiral-multi-path increases the success rate of finding the QoS route. Performance analysis results demonstrate that our SMPQ protocol outperforms other protocols.

The safety problem in access matrix models determines whether a given subject can eventually obtain access privilege to a given object. Generally speaking, the safety problem is, unfortunately undecidable. Not much is known about protection systems for which the safety problem is decidable, except for strongly constrained systems (e.g., monotonic systems). Therefore, we propose the Dynamic-Typed Access Matrix (DTAM) Model, which extends the Typed Access Matrix model of Sandhu by allowing the type of an object to change dynamically. The DTAM model has an advantage that it can describe non-monotonic protection systems for which the safety problem is decidable. In particular, with further restrictions, we can show that the problem becomes NP-hard. In this paper, we formally define the DTAM model and then discuss various aspects of it thoroughly.

This paper presents new results in the field of very low bitrate coding and compression using 3D informations. Contrary to prior art in model-based coding where 3D models have to be known, the 3D models are automatically computed from the original video sequence. The camera parameters and the scene content are supposed unknown and the video sequence is processed on the fly. A stream of 3D models is then extracted and compressed, using adapted compression techniques. We finally show the results of the proposed compression scheme, and the efficiency of this approach.

Davidson's scheme utilizes the order of basic blocks to embed a digital signature in a computer program. To preserve the function of the original program, additional jump instructions are inserted. This involves some overhead in both size and performance. In our implementation, the increase in size was between 9% and 24%. The performance of benchmark programs was 86-102% of the original.

A new approach for electronic sealed-bid auctions that preserve the privacy of losing bids is presented. It reduces the number of operations performed by the auctioneers to O(log ); previous protocols require O(N ) or O(N log ) where the number of bidders is N and that of available bidding prices is . Namely, the number of auctioneers' operations in our auction protocol is independent of the number of bidders. This feature offers strong advantages in massive auctions. We also propose a new scheme that checks the equality of two values without disclosing them. The scheme enhances our basic auction protocol, in terms of security and communication costs.

Data compression is popularly applied to computer systems and communication systems. Especially, lossless compression is applied to text compression. Since compressed data are very sensitive to errors, several error control methods for data compression using probability model, such as for arithmetic coding, have been proposed. This paper proposes to apply an unequal error protection, or a UEP, scheme to LZ77 coding and LZW coding. This investigates a structure of the compressed data and clarifies a part which is more sensitive to errors than the other by using theoretical analysis and computer simulation. The UEP scheme protects the error-sensitive part from errors more strongly than the others. Computer simulation says that the proposed scheme can recover from errors in the compressed data more effectively than the conventional methods.

This paper proposes a test generation method using several partly compacted test plan tables for RTL data paths. Combinational modules in data paths are tested using several partly compacted test plan tables. Each partly compacted test plan table is generated from each grouped test plan set and is used to test combinational modules corresponding to the grouped test plans. The values of control signals in a partly compacted test plan table are supplied by a test controller. This paper also proposes the architecture of a test controller which can be synthesized in a reasonable amount of time, and proposes a test plan grouping method to shorten test length for data paths under a test controller area constraint. Experimental results for benchmarks show that the test lengths are shortened by 4 to 36% with -9 to 8% additional test controller area compared with the test generation method using test plans.

This paper proposes complex form BandPass Sampling (BPS) that is suitable for the software radio. This BPS utilizes offset frequency sampling and quadrature component interpolation. Three types of BPS techniques are first reviewed, which shows effectiveness of the proposed BPS technique. The major advantages over the conventional BPS techniques are: i) free from the DC offset that is caused by the leak of the sampling clock harmonics into the received signal, and ii) reduction of alias by the complex number processing in the signal detection. Next, detailed description of the BPS operation shows that it requires real-time interpolation for the time alignment of the sampled quadrature component. Finally, computer simulation shows that the misalignment generates distortion, and that effective interpolation techniques can reduce the distortion level less than -60 dB even for wideband signals.

A novel method is presented to compute moments of high-speed VLSI interconnects, which are modeled as coupled RLC trees. Recursive formulae of moments of coupled RC trees are extended to those for coupled RLC trees by considering both self inductances and mutual inductances. Analytical formulae for voltage moments at each node are derived explicitly. The formulae can be efficiently used for estimating delay and crosstalk noise. The inductive crosstalk noise waveform can be accurately and efficiently estimated using the moment computation technique in conjunction with the projection-based order reduction method. Fundamental aspects of the proposed approach are described in details. Experimental results show the increased accuracy of the proposed method over that of the traditional ones.

In the hardware synthesis from a high-level language such as C, the bit length of variables is one of the key issues for the area and speed optimization. Usually, designers are required to optimize the bit-length of each variable manually using the time-consuming simulation on huge-data. In this paper, we propose an optimization method of the fractional bit length in the conversion from floating-point variables to fixed-point variables. The method is based on error propagation and the backward propagation of the accuracy limitation. The method is fully analytical and fast compared to simulation based methods.

Development of non-invasive techniques to measure blood sugar level is strongly required. The application of millimeter waves has a great potentiality to realize the measuring technique. Nevertheless, the practical method of the technique is not yet reported. In this paper, a new technique is proposed to measure blood sugar level using millimeter waves. The technique proposed here is very rapid and safety way to obtain blood sugar level.

Effects of the sample insertion holes of the TM010 mode cylindrical cavity are analyzed on the basis of rigorous analysis by the Ritz-Galerkin method. The measurement accuracy of complex permittivity is examined by comparing the values by the perturbation method with ones by the rigorous analysis. Charts of relative errors Δ ε/εp and Δ tan δ/tan δp are presented, which are useful to measure the complex permittivity accurately by the perturbation method. The present analysis extends the validity of the conventional perturbation method.