Abstract: A data processing method for specifying linear conversion for making the number of active S-box maximum, wherein a plurality of linear conversion candidates satisfying a restriction on a circuit for realizing linear conversion candidates are specified among the plurality of linear conversion candidates, linear conversion processing is performed based on a plurality of input data on each of the specified linear conversion candidates, a minimum value of the number of zeros arisen in processing results thereof (a so-called active S-box) is obtained, a linear conversion candidate making the minimum value largest is specified, and a linear conversion portion is configured based on the specified linear conversion candidate.

Abstract: According to the configuration of the present invention, the modulation clock signal is generated in accordance with a signal based on a random number, and a data processing timing is determined in accordance with the modulation clock signal to execute data processing. Accordingly, secret information analysis of an encryption key, a decryption key and the like through measurements of consumption powers in terms of a lapse time of a cryptographic processing apparatus for encrypting and decrypting data, i.e., cryptanalysis based on the power analysis, can be made difficult to thereby realize a cryptographic processing apparatus and method having a high security level.

Abstract: Information to be stored is input to a plurality of information carrier storage means that interact with each other. A unit amount of information carriers is added to a position selected from the information carrier storage means, and nonlinear diffusion of information carriers is executed from the selected information carrier storage means to its neighboring information carrier storage means, and at the same time, nonlinear dissipation is executed from the information carrier storage means. At that time, the dissipation amount is determined so that the amount adding the difference between the amount of addition and the amount of dissipation to the input representation does not exceed a predetermined threshold value. When equilibrium is confirmed as a result of judgement whether changes in amount of information carriers of each information carrier storage means has become small or not, the amount of information carriers stored in the information carrier storage means is output as a numerical value.

Abstract: A data processing method for specifying linear conversion for making the number of active S-box maximum, wherein a plurality of linear conversion candidates satisfying a restriction on a circuit for realizing linear conversion candidates are specified among the plurality of linear conversion candidates, linear conversion processing is performed based on a plurality of input data on each of the specified linear conversion candidates, a minimum value of the number of zeros arisen in processing results thereof (a so-called active S-box) is obtained, a linear conversion candidate making the minimum value largest is specified, and a linear conversion portion is configured based on the specified linear conversion candidate.

Abstract: The present invention provides a method for reliably carrying out an encryption level evaluation process in a common-key block encryption method. To be more specific, an algorithm of a key-scheduling part is expressed in terms of equations represented by vectors and a matrix, and non-linear transformation output values and initial values are eliminated from the matricial equation by carrying out a unitary transformation process in order to find all equations expressing linear relations among round keys. In accordance with the method, it is possible to comprehend all equations expressing linear relations among round keys in the common-key block encryption method without regard to the complexity of key scheduling and evaluate the encryption level of the common-key block encryption method on the basis of the derived equations expressing linear relations among round keys.

Abstract: A method and apparatus, which can transform one multidimensional information pattern into another multidimensional information pattern and inversely transform the multidimensional information pattern having been transformed. Forward transform and inverse transform of a multidimensional information pattern are made by inputting information carriers expressed by n-dimensional vectors (n is a natural number) to a number n of information carrier storing elements which are distributed over an m-dimensional space (m is a natural number) and have the function of holding information carriers in a real number value; repeating processing to apply a predetermined amount of information carriers to the information carrier storing elements and outputting information carriers expressed by n-dimensional vectors from the number n of information carrier storing means.

Abstract: An image processing apparatus capable of extracting widely viewed features of an entire image and speedily performing image processing, and a method and an information recording medium for such processing. Image data of an original image is obtained by imaging the entire original image with an image pickup unit at a time. An amplitude distribution of a signal is obtained from the image data by fast Fourier transform performed by a fast Fourier transform section of a signal processing unit. An amplitude replacement section replaces the amplitude distribution with a predetermined function using the distance from a center of a frequency plane as a parameter. An inverse fast Fourier transform section forms an image corresponding to the original image by inverse fast Fourier transform from a phase distribution of points obtained by the fast Fourier transform and from an amplitude distribution obtained by the above-described replacement.

Abstract: An image processing apparatus capable of extracting widely viewed features of an entire image and speedily performing image processing, and a method and an information recording medium for such processing. Image data of an original image is obtained by imaging the entire original image with an image pickup unit at a time. An amplitude distribution of a signal is obtained from the image data by fast Fourier transform performed by a fast Fourier transform section of a signal processing unit. An amplitude replacement section replaces the amplitude distribution with a predetermined function using the distance from a center of a frequency plane as a parameter. An inverse fast Fourier transform section forms an image corresponding to the original image by inverse fast Fourier transform from a phase distribution of points obtained by the fast Fourier transform and from an amplitude distribution obtained by the above-described replacement.

Abstract: An image processing apparatus capable of extracting widely viewed features of an entire image and speedily performing image processing, and a method and an information recording medium for such processing. Image data of an original image is obtained by imaging the entire original image with an image pickup unit at a time. An amplitude distribution of a signal is obtained from the image data by fast Fourier transform performed by a fast Fourier transform section of a signal processing unit. An amplitude replacement section replaces the amplitude distribution with a predetermined function using the distance from a center of a frequency plane as a parameter. An inverse fast Fourier transform section forms an image corresponding to the original image by inverse fast Fourier transform from a phase distribution of points obtained by the fast Fourier transform and from an amplitude distribution obtained by the above-described replacement.

Abstract: Information to be stored is input to a plurality of information carrier storage means that interact with each other. A unit amount of information carriers is added to a position selected from the information carrier storage means, and nonlinear diffusion of information carriers is executed from the selected information carrier storage means to its neighboring information carrier storage means, and at the same time, nonlinear dissipation is executed from the information carrier storage means. At that time, the dissipation amount is determined so that the amount adding the difference between the amount of addition and the amount of dissipation to the input representation does not exceed a predetermined threshold value. When equilibrium is confirmed as a result of judgement whether changes in amount of information carriers of each information carrier storage means has become small or not, the amount of information carriers stored in the information carrier storage means is output as a numerical value.

Abstract: A semiconductor laser using II-VI compound semiconductors and capable of emitting blue to ultraviolet light is disclosed. The semiconductor laser is configured to sandwich an active layer made of a Zn.sub.x Mg.sub.1-x S.sub.y Se.sub.1-y compound semiconductor where 0.ltoreq.x<1 and 0.ltoreq.y.ltoreq.1 excluding ranges of 1.2y-2.2x.gtoreq.1, 1.3y-3.9x.gtoreq.1, x.gtoreq.0, and y.ltoreq.1 by an n-type cladding layer and a p-type cladding layer from opposite sides.