Abstract: The present invention relates to a method for embedding a watermark into a black and white or color digital image [D(x)]. Basically the inventive method comprises the steps of transforming the digital image using a wavelet transform [WC(y)], transforming a watermark using discrete cosine transform (DCT), integrating the wavelet-transformed digital image with the DCT-transformed watermark [DW(x)+WC(y)] to insert the watermark into the image, and generating the watermarked image using inverse wavelet transform [D(x)?]. For color images, RGB mode is converted into YIQ mode using a conversion matrix and the wavelet transform is applied to the Y-, I-, Q-values. This inventive digital watermarking of a color image is found to be highly robust against lossy compression and other image processing operations, compared to conventionally known methods which are known to be unsuitable for watermarking color images.

Abstract: For the purpose of designing watermark to be robust against image modification such as geometric modification (rotating, cutting, enlarging/shrinking, etc.), compression, and blurring, the watermark is embedded in frequency domain after formed as 2 dimensional shape, for example radial or concentric shape. In detecting watermark, it is possible to effectively detect the watermark, by using relation to a generated watermark in case where the peak is detected.

Abstract: In embedding a watermark in a digital audio contents, a model using a minimum audible limit of the digital audio contents is generated and a series of pseudo random number is masked to generate the watermark to be inserted in the digital audio contents In order to extract the watermark embedded in the digital audio contents, an auditory psychological model having a minimum audible limit, which depends on the characteristic of frequency generated from the digital audio contents, is formed to generate the watermark from a series of pseudo random number. After generating the watermark, the length of the watermark is adjusted according to the relationship of a signal processing between the adjacent digital audio contents. By measuring the correlation between the watermark and digital audio contents, it is possible to detect whether the watermark is inserted or not.

Abstract: The object of the present invention is providing the apparatus and method for controlling playing and copying the digital audio contents by way of embedding the control code into and extracting the control code from the digital audio contents. To achieve the object of the invention, the present invention includes control code embedding apparatus which includes timing deciding part for distributing control code, control code embedding part and digital audio signal summing part, and control code extracting apparatus which includes distribution information collecting part, control code discerning part, and decoding/instruction generating part.

Abstract: The present invention provides a hydrogen-absorbing alloy system of ultra high capacity for electrode of secondary battery. In accordance with the present invention, the hydrogen-absorbing Ti alloy system is represented as a following general formula:Ti.sub.A Zr.sub.B V.sub.C Mn.sub.D Ni.sub.E M.sub.Fwherein, M represents at least one metal which is selected from the group consisting of Cr, Co, Fe, Cu, Al, Si, Hf, Nb, Mo and R.E., where R.E. represents at least one metal which is selected from the group of rare-earth elements consisting of La, Ce, Pr, Nd and Sm; and, A, B, C, D, E and F have atomic ratios ranging 0.2.ltoreq.A.ltoreq.0.35, 0.03.ltoreq.B.ltoreq.0.15, 0.15.ltoreq.C.ltoreq.0.4, 0.8.ltoreq.D.ltoreq.0.2, 0.13.ltoreq.E.ltoreq.0.35 and 0.ltoreq.F.ltoreq.0.1, respectively, with the proviso that A+B+C+D+E+F=1 and A+B.ltoreq.0.45.

Abstract: The present invention relates to a material for hydrogen-storage constituted by Ti-Mn alloy system which has a high hydrogen-storage capacity, plateau hydrogen dissociation equilibrium pressure, hypostoichiometric composition and crystal structure of C14. Ti-Mn alloy system for hydrogen-storage of the invention which has a C14 crystal structure, is represented as: Ti.sub.u Zr.sub.v Mn.sub.w Cr.sub.x V.sub.y X.sub.z, wherein, X is at least one of element selected from the group consisting of Fe, Al and Ni; u, v, w, x, y and z are mole numbers of each components; 0.7<u<1.0; 0<v<0.3; 1.0.ltoreq.w.ltoreq.1.3; 0.1.ltoreq.x.ltoreq.0.4; 0<y<0.3; 0.ltoreq.z.ltoreq.0.2; 0.7<u+v<1.0; 1.4.ltoreq.w+x.ltoreq.1.7; and, 1.3.ltoreq.w+x+y+z<2.0.

Abstract: The present invention provides a method of activation treatment of a Ni/MH secondary battery which comprises a step of immersing an electrode or battery in a solution or electrolyte and charging/discharging concurrently. In accordance with the activation treatment of a Ni/MH secondary battery by hot-charging method of the invention, the time required for activation treatment is remarkably saved and the activation process is carried out in a highly efficient manner, compared to the conventional methods of activation treatment.

Abstract: The present invention relates to a process for preparing an electrode for secondary battery employing hydrogen-storage alloy systems, more specifically, to a process for preparing an anode material for secondary battery which can be charged/discharged in an electrolyte and has a high discharge efficiency and energy density per unit weight, by sintering a mixture of hydrogen-storage alloy systems. An electrode for secondary battery of the present invention is prepared by the process which comprises the steps of: (i) mixing a hydrogen-storage alloy powder free of Ni with a hydrogen-storage alloy powder containing Ni over 30 atomic %; (ii) cold-pressing the mixed powder at a pressure of 5 to 15 ton/cm.sup.2 ; (iii) sintering the cold-pressed mixture in a quartz tube at 900.degree. C. for 5 to 15 min under a vacuum condition of 10.sup.-2 to 10.sup.-3 torr; and, (iv) quenching the sintered material.

Abstract: The present invention relates to a method of measuring residual capacity of a Ni/MH (nickel/metal hydride) cell by measuring the change in the electrical resistivity of a Ni/MH cell according to the change of the concentration of hydrogen in metal hydride. According to the present invention, a method for measuring residual capacity of a Ni/MH cell comprises the steps of measuring electrical resistivity of a first Ni/MH cell, and determining the residual capacity of the first Ni/MH cell (i) from a predetermined data of n-pairs of electrical resistivity values and residual capacity values of a second Ni/MH cell which has substantially the same composition as the composition of the first Ni/MH cell, or (ii) based on a predetermined functional relationship between the electrical resistivity and residual capacity of the second Ni/MH cell.

Abstract: A nickel/metal hydride secondary battery which exhibits a minimal amount of self-discharge, the secondary battery having battery cells in which the environment thereof is a gas environment of hydrogen gas or a hydrogen-inert gas mixture.