By the location of a vanishing point of an object in a picture we can determine the spatial relationship between the object and the observer. In this paper we present a technique for determining its location by Hough transformation. As an application we present a method of calculating panned angle of the observer.

Convergence properties of adaptive algorithms are analyzed and compared with mutually by using the differential equation approach. Evaluations of the convergence rates of the algorithms are made by the eigenvalues of matrix coefficient which are relating to the radio environment and the guideline of adaptation. The result shows that the adaptive array under directional constraint is the most applicable to communications for fixed stations or stations in predictable motion despite of its slower convergence rate, because it requires only an approximated information about the desired signal. But, for a desired signal whose incident direction is unknown at the receiver, only the least-mean-square-error adaptive array can extract the desired signal from noisy environment, if a synchronization between the received desired signal and the internal reference signal is kept.

This paper shows the necessary and sufficient condition for an admittance matrix to be realized as a network composed of three reactance two-ports and two resistors connected in cascade.

Electrostatic drop forming characteristics of using a metal nozzle are compared with that of using glass nozzles. Taking the surface tension values of liquids as a parameter, we made experiments and concluded that the electroconductivity of liquids has prominent effects on drop formation for low surface tension liquids.

Error correcting and/or detecting codes have been successfully used to improve the reliability of computer memories. To improve for error control in memory systems organized to have b bits per package, a new class of linear codes for simultaneous error correction and error detection is given. We refer to a group of b bits as a byte. This paper provides a new type of byte error detecting codes to correct single bit errors and detect single byte errors (SEC-SbED codes), and to correct single bit errors and detect double bit errors and single byte errors (SEC-DED-SbED codes). Form these codes, this paper demonstrates a new class of rotational SEC-SbED codes and rotational SEC-DED-SbED codes that are optimal for LSI construction of their encoding-decoding circuitries. The decoders for the proposed codes require very small amounts of extra circuitry over that required for SEC-DED (Single Error Correcting - Double Error Detecting) codes. The decoding speed is very high-equal to that of SEC-DED codes.

A novel and efficient multiplication algorithm, called "duo-multiplication", is proposed. Two multiplications and the sum of their results are calculated directly, with the same number of operation steps as is required for the conventional single multiplication. The algorithm is derived from adjusting non-zero partial product generation timing in order to interleave one multiplication execution into the other multiplication execution. This timing adjustment is realized by utilizing the fact that any two algebraic numbers in two's complement representation can be transformed into a binary signed digit representation pair, in which the non-zero digits of one number do not overlap with those of the other number, without increasing total word length. As duomultiplication operation is fundamental on digital signal processing, the algorithm adoption doubles signal processing capability of a microprocessor.

A simple method of evaluating diversity effects in the design of land mobile radio systems is introduced, and power reduction and spectrum utilization are discussed. First the processes for determining transmitter power and frequency reuse distance, which are very important factors in system design, are derived. In this derivation, the probability of a fade below a given threshold level and the probability of co-channel interference are calculated for systems operating in Rayleigh fading and lognormal shadowing environments. The probabilities are presented by simple form applicable to system design. Then, based on the derivation, a method of evaluating diversity effects is shown by taking the case of selection diversity. The results show how these effects can be taken into account in system design.

The class of contour map patterns, for example, geographic elevation map and isobar map, is an important class of pictorial data. Its storage and retrieval management have serious implications in the context of a pictorial data bank organization. In this context, we propose the use of the global description of contour map, a string representation called GDCM, for the storage organization of contour maps. We first present a summary of the basic ideas and concepts that leads to the structural description of contour map and then formulate the global description. To take into consideration the frequencies of occurrence of contour clusters (GDCM symbols), we encode the GDCM, which serves as indexes to contour maps, with the Huffman coded GDCM symbols. After organizing the set of encoded GDCM strings into a digital tree for storing the contour maps, we discuss the resulting space and time complexity. We then apply the above ideas to the storage organization of weather maps and evaluate the space and time complexity of the resulting storage structure. The evaluated results indicate that our proposed storage structure for contour map is a viable one.

This paper describes a Method of recognizing Hangeul (Korean Characters) which is based on the structural analysis of characters. The experiment results obtained through computer simulation are given. In recognition of Hangeul composed of 24 basic character elements, we pay special attention to regular combinational rules for character formation. The recognition system is composed of three major processing parts: Extraction of character elements, Recognition of each character element and Syntactic reconstruction of a character based on the recognized character elements. The character elements which failed in the syntactic reconstruction are sent back to the character element extraction process again, providing the flexibility to adopt to the more advanced experiments. We first present the structure of Hangeul for feature extraction. Next, some processing algorithms are described and simulated. The experiment results demonstrate the effectiveness of the proposed recognition system.

In multi-carrier satellite communication systems, many modulated carriers have to be co-amplified through a TWTA (Traveling Wave Tube Amplifier). In such a case, the intermodulation due to the TWTA nonlinearities i.e., AM/AM and AM/PM conversions degrades that system performance. This paper analyzes the combined effects of the AM/AM and AM/PM conversions on the output properties of the TWTA using a quadrature nonlinear model. A general formula of the output autocorrelation function is derived as a function of the input autocorrelation function with an arbitrary input power spectrum. Based on this formula, the effects of the TWTA nonlinearities (both AM/AM and AM/PM conversions) on the output characteristics such as the output signal and intermodulation power, the intermodulation power spectral distribution, and the output signal-to-intermodulation ratio (SIMR) are theoretically evaluated.

Various calculations of derivatives, dealing with specific spaces, have been studied to define cubic splines. Some Modified 3-Point Methods have been proposed which would reduce the amount of calculations required. These methods enable us to preceive the result from a computer by lines. Some theorems that are useful for the discussion of local calculations are given and examples are executed to compare our methods with the original cubic spline functions. The results given in this paper have demonstrated a relation to the interactive computer graphics as well as the interpolation of data points.

What is required for the functional testing of modern high-density and fast IC and large scale integration (LSI) circuits is a method which has a time resolution in the subnanosecond region and a spatial resolution in the submicrometer region. Furthermore, the test probe must be easy to position on the circuit. To meet these requirements, a combined stroboscopic SEM-microcomputer test system has been developed. A microcomputer is used for striking the electron beam to a point of interest on the specimen surface, sampling and storing the signal waveforms, performing an operation of signal processing, and generating a data display or data output in numerics. Following a system description, application to a MOS LSI (4 k bit static random access memory-RAM) in the MHz regions is reported to demonstrate the efficiency of the system.

The authors implemented a directionally-constrained adaptive array system in an audio-frequency range. This system has a good prospect of applications since it does not require a rigorous a priori knowledge of the desired signal. Its algorithm contains matrix calculation, for which some technique has to be devised in implementation. For this, data are sampled and A-D converted so that the necessary processing for feedback control may be done by a microcomputer in digital form. The signal path remains in analog form, which will allow us to extend the system to higher frequency range. The performance of the system is demonstrated through the experiments. Effects of hardware errors are found: (1) Nulling behavior against the interference is not affected at all by virtue of the feedback control. (2) A little deviation from the constrained response to the desired signal is perceived. The behavior against a wideband interference is investigated analytically and experimentally. It was found that the final SIR becomes lower with wider frequency bandwidth.

Self-healing breakdowns of anodic Y2O3 films with the thickness of 500 to 2000 have been measured. The measurements reveal that the breakdown is a single-hole type and that the breakdown field, which is closely correlated to the anodizing field, is independent of the Y2O3 thickness. An ionic motion is considered to the effective in initiating the breakdown which forms a conducting channel through the Y2O3 film. The energy of the breakdown spot formation is calculated assuming the thermochemical evaporation process of the substances. It agrees well with the discharged energy of the specimen capacitor at the breakdown.

This paper deals with an elementary alternative approach to the notion of the principal partition of a matroid into strongly irreducible minors. This approach makes use of the matroid union theorem and the concept of the density of a matroid introduced in this paper. For a matroid M on S the density d(M)S/r(M). The principal partition of a matroid M on S is constructed by first constructing a partition of S called the P-sequence of M. On the resulting sub-sets irreducible minors are constructed. An irreducible minor is further partitioned into strongly irreducible minors by examining all its restrictions of density equal to its own. It is constructively shown that the P-sequence of a matroid M can be obtained by considering the intersections of sets of coloops of matroids obtained from M by repeated use of the matroid union () and the dualization (*) operator. It is shown that the principal partition for such matroids can be immediately constructed if the principal partition for the original matroid were given. Finally, efficient algorithms are outlined for constructing the principal partition.

The concept of essential minimality for closed sets of multiple-valued logical functions is introduced and studied. Principal results include: (1) any essentially minimal closed set can be generated by a single function and (2) the number of essentially minimal closed sets is finite.

Equivalent network approach has been applied to the guided wave problems in the dielectric thin-film waveguides for optical integrated circuits. The results by this approach for the rib waveguide and the optical strip waveguide agree well with the results by the numerical approaches.

Formal descriptions for constructing a Joel's permutation network are discussed. We show that a setting algorithm of the network can be described in terms of bipartite graphs. We then study a fast parallel algorithm for setting the network. We show that it can be implemented by a parallel computer with N processors in O((log2 N)2) time, where N is the size of permutations produced on the network.

Acoustic distributed feedback (ADFB) lasers with stripe active regions for current injections have been theoretically analysed. The theory is based on a coupled-mode analysis employing Bragg guided modes. The characteristic equation of oscillation for the two-dimensional DFB laser is derived in an explicit form. The mode spectra and the threshold gains for the onset of the oscillation of the ADFB laser are obtained, and the characteristics of the two-dimensional mode structure is discussed. Also discussed is the effect of complex photoelastic constants.

An experimental high pressurized ink-jet device is described for reproducing gray level pictures by the pulse-width modulation of picture signals. A reproduced picture with the resolution of about two lines/mm, and seven gray level is obtained for a facsimile test chart which is scanned with the scanning density of five lines/mm, and also a good reproduced picture is obtained for a halftone dot picture.