The velocity that an electrical signal transmits through an electric wire depends on the effective permittivity of the space around the wire. Therefore, when the permittivity of the space around the electric wire changes, propagation delay time changes. This change of the propagation delay time can be easily detected by a simple electronic circuit. The method of detecting the change of the effective permittivity around the electric wire is applicable to various sensing technique in any field. Since human body contains much water and the permittivity of water is very large, this method is especially useful to detect the movement of human body, and is applicable to monitoring breathing, pulse-beat, and so on.
Authors propose multimodal artifact metrics based on multimodal biometric systems. We believe that this technique can verify the authenticity of each artifact more accurately than the existing artifact metrics techniques and can make counterfeiting more difficult by attributing two or more characteristics extracted from different physical characteristics to the artifact. We focus on synthetic resin products (valuable cards) which are confirmed to be counterfeited and create card-shaped samples with two physical characteristics to prove the feasibility of the proposed technique. Results show that the feature information (i.e., sheet resistance and visible light image) extracted from the samples differed, which indicates that such features could be characteristic information and could be used to distinguish each sample.
A walk support system that can provide visually impaired users with information about objects touched by a cane. The goal of the proposed system is to identify five objects, i.e., two types of braille blocks, a pedestrian crossing, the floorboard of a train, and a train gateway, using a cane. Previous studied adopted electronic devices, e.g., RFID tags, to evaluate identification. Conversely, the proposed system employs phosphor powder, a chemical that can emit specific light wavelengths upon optical excitation. The proposed system does not require significant changes to the construction process of identified objects. The phosphor powder is mixed with the construction materials prior to construction. Thus, as compared with method using RFID tags, the proposed system does not require pre-calculation of the proper number and location of tags or changes to the construction method, which are needed for burying RFID tags. We created a specimen from a synthetic resin shaped like a braille block and observed the emission excited by an LED light source. Results demonstrated that more light emission could be observed when the weight percentage and power of the light increased and the distance between prove and the specimen decreased. The peak wavelength could also be seen even though the distance between the prove and specimen was increased. Thus, we confirmed that phosphor powder could be used as the guide object for the proposed walk support system.
We propose a method for generating wallpaper-group images that are generated geometric patterns in the lattices and seamlessly joined patterns between the lattices. The proposed method generates wallpaper-group images by an iterative process using contour line and Euclidean distance. Wallpaper-group images that are generated by the proposed method are characterized that can generate various patterns by the number of iterations. Through the experiment to generate grayscale wallpaper-group images in the image of 500 * 500 pixel size of 50 pixel interval, we verify various patterns by the number of iterations. In addition, by generating color wallpaper-group images which are assigned red, green and blue to three grayscale wallpaper-group images respectively, we also verify that the visual effect is improved.