Queries to generate a map from geographic detabases are too large and complex for users to specify all components in it. Thematic parts of the map should be described by users as ad hoc queries. However, background parts of it should be inferred from users' queries corresponding to the thematic parts. Furthermore, it is important for the map systems to lead users' constructing their ad hoc queries and to infer visualization methods applied to the data retrieved by the ad hoc queries. This paper discusses a framework to infer supplemental queries and visualization methods in order to make the retrieval results into a feasible map using geographic domain hierarchical levels, geographic domain thesauruses and existing example queries. The framework allows users to know mismatches of components in queries, inappropriate queries for maps, and deriving candidates for additional components in queries.

As the Hypertext Transfer Protocol (HTTP) becomes more popular for network communication, network loads in areas with less developed network infrastructures will be an increasing problem. This paper presents a system which extends a WWW-server with a gateway to an RDBMS and a mail program, allowing for interactive query formulation together with return of potentially large query results by e-mail. These results can then be downloaded by the user when network loads are low.

Documents stored in a database system can have complex internal structure described by languages such as SGML. How to take advantage of this structure presents challenges for database system implementors. We classify the types of queries that need to be supported by SGML-conformant database systems. We then describe several data models that have been proposed for representing documents in a database system and discuss the support these models provide for SGML. Finally we consider query evaluation.

A 2-switch node network is one of the most fundamental structure among communication nets such as telephone networks and local area networks etc. In this letter, we prove that a problem of designing a 2-switch node network satisfying capacity conditions of switch nodes and their link, which we call 2-switch node network problem, is NP-complete.

The technique for estimating the parameters of multiple waves provides a convenient tool for analysis of multiple wave-fields and eventually for actual applications to mobile communications. Several algorithms have been proposed for those purposes. However, the best tactics to resolve multiple wave-fields are still imperfectly understood at present. This paper proposes a new method for estimating the angles and power levels of arrival waves based on the extended Kalman filter. A space-variable model which we call a spatial state equation is derived using array element locations and incident angles. It has been shown that by means of the model, the estimation of incident waves can be transformed into the problem of parameter identification in linear system which can be carried out by the extended Kalman filter conveniently. The algorithm is initiated directly by the signal received at each array element. The detailed procedure of an extended Kalman filter approach is given in the paper. The performance of the proposed approach is examined by a simulation study with two signals model. The simulation results show a good estimate performance, even in the case that two waves arrive from close directions.

This paper proposed a practical method of program validation for state-based reactive concurrent systems. The proposed method is of particular relevance to plant control systems. Plant control systems can be represented by extended state transition systems (e.g., communicating asynchronous transition systems). Our validation method is based on state space analysis. Since naive state space analysis causes the state explosion problem, techniques to ease state explosion are necessary. One of the most promising techniques is the partial order method. However, these techniques usually require some structural assumptions and they are not always effective for actual control systems. Therefore, we claim integration and harmonization of verification (i.e., state space analysis based on the partial order method) and simulation (i.e., conventional validation technique). In the proposed method, verification is modeled as exhaustive simulation over the state space, and two types of simulation management techniques are introduced. One is logical selection (pruning) based on the partial order method. The other is heuristic selection based on priority (a priori precedence) specified by the user. In order to harmonize verification (logical selection) and conventional simulation (heuristic selection), we propose a new logical selection mechanism (the default priority method). The default priority method which prunes redundant state generation based on default priority is in harmony with heuristic selection based on the user's priority. We have implemented a practical validation tool, Simulation And Verification Environment for Reactive Concurrent Systems (SAVE/RCS), and applied it to chemical plant control systems.

Due to the large and complex information processing systems, formal description methods are needed for specification of systems and their efficient and reliable designs. During the early stage of system design, it is often necessary to modify or change system requirements which may influence the whole system design. We have proposed a new flexible description methodology, which copes with the modifications or changes in the system requirements, in order to obtain the formal specification of the system. We have also shown that function requirements can be modeled by a Logical Petri Net (LPN), which is a kind of extended Petri Nets, in order to derive the formal specification. In this paper, we propose a verification method of system requirements that contain some kinds of logical errors. Further, we show a method to decompose and refine a requirement description hierarchically, and discuss how to derive a formal specification from a requirement description flexibly along our refinement method against the changes of the requirement description in the system.

Recently, some speech recognition methods using fusion of visual and auditory information have been researched. In this paper, a study on the mouth shape image suitable for fusion of visual and auditory information has been described. Features of mouth shape which are extracted from gray level image and binary image are adopted, and speech recognition using linear combination method has been performed. From results of speech recognition, the studies on the mouth shape features which are effective in fusion of visual and auditory information have been performed. And the effectiveness of using two kinds of mouth shape features also has been confirmed.

As Object-Oriented Database Systems (OODBS) play an increasingly important role in advanced database systems, OODBS performance becomes a significant issue. It is well known that there is a strong relationship between performance and the concurrency control algorithms employed by the Database Management System (DBMS). Class Granularity Locking (CGL) and Class Hierarchy Granularity Locking (CHGL) are proposed as the concurrency control algorithms for OODBS to minimize the locking overhead. However, their basic characteristics, including the licking overhead and concurrency, have not been extensively investigated and it is not known which one is most appropriate for the general case. In this paper, we construct a simulation model for OODBS and carry out several performance evaluation studies on these two Class-Hierarchy Locking protocols and the Non Class-Hierarchy Locking (NCL) protocol. The NCL protocal is a variation of the conventional two phase locking protocol being applied to OODBS data structures.

In this paper, we discuss an abstraction method for Petri nets based on an equivalence of firing sequences of a specified subnet or a specified subset of transitions. Specifically, a method is presented to generate an equivalent net which preserves firing sequences of a specified subnet or a specified subset of transitions. The abstraction can be applied to an efficient behavioral analysis of concurrent systems constructed by composition of modules such as communication networks and Flexible Manufacturing Systems (FMS).

Genetic Algorithm (GA) is the method of approaching optimization problem by modeling and simulating the biological evolution. As the genetic algorithm is rather time consuming, the use of a parallel genetic algorithm can be advantage. This paper describes new methods for fine-grained parallel genetic algorithm using a multiprocessor system FIN. FIN has a VLSI-oriented interconnection network, and is constructed from a viewpoint of fractal geometry so that self-similarity is considered in its configuration. The performance of the proposed methods on the Traveling Salesman Problem (TSP), which is an NP-hard problem in the field of combinatorial optimization, is compared to that of the simple genetic algorithm and the traditional fine-grained parallel genetic algorithm. The results indicate that the proposed methods yield improvement to find better solutions of the TSP.

In this paper, a pushdown automaton, with an infinite set of states as a partially ordered set (poset), is formulated, and its control problem of whether a given configuration can be transferred to another is discussed. For the controllability to be decidable, we take a condition the poset satisfies, that is, a condition that there are only finite number of states under the partial ordering between two given states. The control problem is decidable in polynomial time on condition the length of each pushed stack string is bounded by a constant in a given pushdown automaton. The motivation of considering the control problem comes up from the stack structure in implementing the SLD resolution deductions, in which the leftmost atom in each goal is selected and unified with some procedure name (that is, some head) of a definite clause, with the effect of the procedure name being replaced by the procedure bodies and unifications. Thus, the control problem is applied to describe the SLD resolution deductions of finite steps, by constructing a pushdown automaton model for a set of definite clauses, in which leftmost selection of atom in each goal forms a stack structure and substitutions affecting goals are interpreted as states. When constructing a pushdown automaton model for an SLD resolution deduction, algebraic properties of the idempotent substitution set, which are used in unifications, are examined and utilized. The quotient set of the idempotent substitution set per renamings is adopted to present the automaton model.

The coherence in the time movement of the spectral vector sequence is modelled by a vector linear predictor. Such a model of the stop consonant transition is used for discrimination of the places of articulation of/ba/,/dha/,/da/, and/ga/. The effect of cross-channel correlation in giving improved recognition performance and also in reducing the time asymmetry of the predictive recognizer is studied. The high recognition score of vector model and the considerable differnce in the forward reverse score of the scalar model than a vecter model is highlighted in this study on a speech data of a set of four speakers.

When signal subspace techniques, such as MuSIC, are used to locate a number of incident signals, an exhaustive search of the array manifold has to be carried out. This search involves the evaluation of a single cost function at a number of points which form a grid, resulting in quantization-error effects. In this paper a new algorithm is put forward to overcome the quantization problem. The algorithm uses a number of cost functions, and stages, equal to the number of incident signals. At each stage a new cost function is evaluated in a small number of "special" directions, known as characteristic points. For an N-element array the characteristic points, which can be pre-calculated from the array manifold curvatures, partition the array manifold into N-1 regions. By using a simple gradient algorithm, only a small area of one of these regions is searched at each stage, demonstrating the potential benefits of the proposed approach.

Scientific database systems for the analysis of genes and proteins are becoming very important these days. We have developed a deductive database system PACADE for analyzing the three dimensional and secondary structures of proteins. In this paper, we describe the statistical data classification component of PACADE. We implemented the component for cluster analysis and discrimination analysis. In addition, we enhanced the aggregation function in order to calculate the characteristic values which are useful for data classification. By using the cluster analysis function, the proteins are thereby classified into different types of structural characteristics. The results of these structural analysis experiments are also described in this paper.

An interactive painting system for generating calligraphy words is developed. Its significant advantage lies in effective rendering functions that synthesize kasure and nijimi textures due to the effects of brush and absorbent painting paper. The system enables users to generate high quality and realistic calligraphy words.

A new method is developed to generate fuzzy rules from numerical data. This method consists of two algorithms: Algorithm 1 is used to identify structures of the given data set, that is, the optimal number of rules of system; Algorithm 2 is used to identify parameter of the used model. The former is belonged to unsupervised learning, and the latter is belonged to supervised learning. To identify parameters of fuzzy model, we developed a neural network which is referred to as Unsymmetrical Gaussian Function Network (UGFN). Unlike traditional fuzzy modelling methods, in the present method, a) the optimal number of rules (clusters) is determinde by input-output data pairs rather than by only output data as in sugeno's method, b) parameter identification of ghe present model is based on a like-RBF network rather than backpropagation algorithm. Our method is simple and effective because it integrates fuzzy logic with neural networks from basic network principles to neural architecture, thereby establishing an unifying framework for different fuzzy modelling methods such as one with cluster analysis or neural networks and so on.

The interstitial hyperthermia is an invasive heating method applied by inserting the applicator into the human body. We have been studying on coaxial-slot antennas for interstitial microwave hyperthermia. The characteristics of the square antenna array were theoretically examined. Firstly, the basic structure of the antenna, and a simplified analysis model taking account of the effect of the boundary surface were explained. Then analysis was performed by using the moment method. Finally, the calculated results were discussed. The catheter thickness has much effect on the characteristics and must be considered both in designing and in using the antenna. When the array spacing was increased, the effective heating area became larger and more uniform. As the insertion depth was increased, the effective heating area was also enlarged.

Tilt margins for disk and lens for a magneto-optical (MO) head were studied for designing a disk system for use with objective lenses having numerical apertures (NA) of 0.55, 0.60, and 0.65. The tilt margins were examined to determine the aberration characteristics of objective lenses and bit error rate (BER) by recording and reproducing signal. In preparing the optical head for testing disk and lens tilt margins, the aberrations were measured by image processing from the CCD area sensor for the spot image of the focused beam, and BER dependencies on the tilting of lens and disk were obtained at the velocity of the outer diameter of the MO disk at the bit rate of 80-Mbps (1, 7 code modulation) recording. According to the aberration and BER characteristics, the limitation for effective wavefront aberration would be 0.05λ rms, the tilt margins corresponded to BER limitation at the level of 3*10-5. The disk margins for NA=0.55, 0.6, and 0.65 were 0.4, 0.2, and 0.1 degrees. The lens tilt margins for NA=0.55, 0.6, and 0.65 were 0.2, 0.1, and 0.05 degrees.

Tremendous progress has been made in magnetic data storage by applying theoretical considerations to technologies accumulated empirically through a great deal of research and development. In Japan, the recording demagnetization phenomenon was eagerly analyzed by many researchers because it was a serious problem in analogue signal recording such as video tape recording using a relatively thick magnetic recording medium. Consequently, perpendicular magnetic recording was proposed as a method for extremely high-bit-density recording. This paper describes the theoretical background which has resulted in the idea of perpendicular magnetic recording. Furthermore, the possibility of magnetic recording is discussed on the basis of the results obtained theoretically by magnetic recording simulators. Magnetic storage has the potential for extremely high-bit-density recording exceeding 1 Tb/cm2. We propose the idea of 'spinic data storage' in which binary digital data could be stored into each ferromagnetic single-domain columnar particle when the perpendicular magnetizing method is used.