The eating quality of rice is evaluated by six attributes such as appearance, flavor, stickiness, hardness, taste and overall judgement. Taste can be measured with a multichannel taste sensor which uses lipid membranes as the receptor part. The sensor responds to each food by changes in the electric potentials from eight kinds of lipid membranes. In this paper, we investigated the taste of rice with a multichannel taste sensor. Four kinds of foreign cultivated rites and six brands of domestic rices (Koshihikari, whose producing district differed from each other) were used as samples. Following results were obtained.
1) Each type of rice was distinguished by output patterns of eight electric potentials in the taste sensor.
2) Using principal component analysis applied to these data, rices were clearly classified into two groups of domestic and foreign ones, whereas rice produced in Australia was close to domestic rices.
3) Sensory evaluations of cooked rites were made, and the result, was found to correlate with outputs of the taste sensor.
4) Fresh rice was distinguished from rice, which was stored for one month in sunshine, using the taste sensor.

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This paper presents a study on discriminating material properties by touch sensors based on the neuro algorithm. The authors firstly pointt out that the multi-layer artificial neural network has good results for discriminating material properties. However, it exhausts tremendous time to get synapses by the standard learning method (SLM). To solve the problem, the authors propose an improved neuro algorithm with such process as dividing all samples into several groups, learning synapses within a group by the mean learning method (MLM), and learning synapses between groups by the simulated annealing.
In the paper, a numerical simulation is also described for verifying the proposed algorithm, from which good classification resulted for some materials such as iron, aluminum, copper, brass, rubber, wood and styrene foam. We think that the study is useful to developing an artificial skin tactile sensing system in the future.

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A computational model of echolocation was investigated for unambiguous measurement of the range and velocity of a moving object. Based on the time-frequency structures of echolocation sounds utilized by some species of 'FM bats', a linear-period modulated (LPM) signal was used in the model. Motivated by the study reported by P.A.Saillant et al., we introduce in this paper a new mechanism for motion parameter estimation by adopting a voting mechanism according to output phase values across a bank of constant-Q filters. Resultant histograms of the phase values along the the temporal axis provide a two-dimensional map in which a maximum peak of the histograms gives a clue to perceive the existence of an object and estimate the corresponding motion parameters. Experimental results of motion parameter estimation performed in air are presented in comparison with a conventional correlation detection of chirp signals. Regardless of the relatively small time-bandwidth product of the LPM sound used in the experiments, the estimation accuracy was better than 0.05[m/s] for velocity and about 0.3[mm] for range. In contrast, reliable results were not obtained because of the ambiguous property in parameter estimation if the time-frequency structure of chirp sounds was inappropriately designed.

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For extracting simple and informative measures for describing time-varying natures of musical sound and speech, we construct a wavelet energy distribution and orthogonally decompose instantaneous changing energy of it into three primary components: 1) loudness change, 2) pitch shift, and 3) timbre change according to the coherency in power magnification and frequency shift. The decomposition is performed in the time-frequency gradient space, and the power ratios of three components are transferred as signals to higher processing stages. Several experiments show that these signals have superior resolution and sensitivity for segmenting dynamical nature of speech, musical sounds, and so on.

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This paper describes a three-dimensional (3-D) inspection system for small 3-D and reflectance defects of an arbitrary surface. We fix a TV camera in front of the object, and along the viewing axis we move a random dot projector at a constant speed. After taking the first image sequence, we shift the object by a slight known amount, and take the second image sequence in the same way. Applying the spatio-temporal gradient method, we extract gradient patterns of surface depth and surface reflectance distributions. We applied this method to visual inspection and classification of fine surface defects such as cracks, flaws, stain, and rust. We show this system could detect up to 5μm flaws and 1% reflectance change from a 50cm distant measuring apparatus.

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A heat resistant capacitive sensor was developed to study the fracture dynamics of metallic materials at elevated temperatures by acoustic emission (AE) source inversion analysis. An amorphous alumina film of 3μm thickness was deposited on the stainless sensor core by an electron cyclotron resonance infrared laser physical vapor deposition (ECR-LPVD). Calibration according to the modified surface impulse deconvolution method revealed that the sensor measured the out-of-plane displacement of hot medium up to 873K with a sensitivity of 10⁷V/m.

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We have experimentally confirmed the film operation of an electrostatically-driven S-shaped film actuator in a liquid environment and investigated response time as the function of a micro-fluid-control device. The actuator has an S-shaped film element whose S-shape travels laterally by electrostatic force. We used a hand-made model of the actuator. Film operation was carried out during immersion in silicone oils of different viscosities. The film was able to be successfully operated by electrostatic force under all viscosity conditions. The film travel is separately discussed in two different regions, which are acceleration and terminal velocity motion. The terminal velocity of the S-bend was proportional to the square of the applied voltage and was inversely proportional to the viscosity of the silicone oil. The velocity was 90mm/s when the film driving voltage was 220V.

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