A method to measure the depth of open cracks in steel by laser ultrasound was developed. Surface waves were measured using a specimen with a slant slit whose depth varied continuously from 0 to 5 mm. The results showed that the time delay of the transmitted wave can be used to monitor the crack depth. When the specimen temperature was varied, the time delay varied because of the change in the propagation speed of the surface wave. In order to remove the effect of temperature change, a method using two surface waves was developed. The time delay of the reference wave, which only includes the effect of temperature change, was used to correct the time delay of the transmitted wave, which includes the effects of temperature change and crack depth. This method was shown to be effective in eliminating the effect of temperature change in the range from 25°C to 500°C

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In this paper, the architecture for high-sensitivity and wide-range CMOS temperature sensor circuits is presented. The proposed architecture consists of the PTAT circuit with the positive slope, the PTAT circuit with the negative slope and a subtractor. The concrete circuit based on the proposed architecture is designed, and evaluated through HSPICE with a set of device parameters of 0.18μm CMOS process. The simulations demonstrate a maximum temperature error of 2.3°C and the maximum current consumption of 28.7μA under the condition that the temperature range is from -20°C to 100°C, the sensitivity is 5.2mV/°C and V_DD=1.5V.

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A novel cavity resonator method was proposed for measuring the complex permittivity of dielectric plate and film in the millimeter-wave region. In this method, the dielectric plate with film was loaded at the end of the cavity resonator. The measurement principle and the measurement error of the dielectric film were discussed. The complex permittivities of dielectric films were measured at 30 GHz.

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In Japan, as the number of elderly persons increases, the demand for confirming the safety of these persons is also increasing. In order to confirm the safety of these elderly persons, various safety confirmation systems have been developed. One such example is a safety confirmation system which was developed to monitor the usage of an electric pot. In light of this, we developed a service system to confirm the safety of elderly persons by monitoring electric power consumption. This system cancels out the differences in electricity usage of each household from the differences in consumed power, making it unnecessary to conduct individual tuning. However, even this system cannot detect abnormalities in all cases. For example, our system could not detect abnormal states of elderly persons during times such as when they are bathing and sleeping. To overcome this we developed a new sensor system which is capable of monitoring situations, including when bathing, that until now have not been able to be successfully monitored. In this new system, we have also included a method to reduce quantity of detection data transmission by sorting information, depending on the degree of the emergency. The use of this new sensor system enabled us to pick up any blind spots that had not been monitored in safety confirmation during the monitoring of electric power consumption, and reduce the quantity of detection data transmission.

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The purpose of this study is to develop a wireless networked lighting system for office buildings, which can reduce the energy consumption while meeting users' lighting preferences. By using particle swarm optimization, the system is able to optimize the dimming ratio of luminaires according to the real time natural illumination and occupancy condition.
In this paper we make a prototype system and test the feasibility and efficiency of the system. The prototype consists of one wireless control module, three illumination sensors and four fluorescent lamps with dimming capacity. The illumination sensors collect and send the data to the control module. After the process of PSO (Particle Swarm Optimization), the module finally sets the power of the lamps according to the PSO result.
After real experiments in a certain designed office, it was proved that the system can successfully control the illuminations, and can save considerable energy.

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Authors proposed the machine control technique for manipulating man's condition by the iterative learning control (ILC) based on the biomedical signal. However, there was a possibility that ILC becomes unstable when the system with low repeatability like man was included in controlled object. Then, “Adaptive type ILC (ATILC)” that adjusted the learning gain according to the characteristic change of controlled object at each trial was newly proposed in this paper. The ATILC adjusts learning gain by using the model parameter after controlled object is modeled by first-order delay based on the time series of I/O in one trial of controlled object. Even if controlled system is accompanied by the property change, the output trajectory of controlled object follows to objective one by ATILC. The effectiveness of the proposed method was confirmed by simulation work by using the approximation model of biological signal.

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An experimental study to visualize and measure the concentration distribution of hydrogen gas flow using the Raman scattering was performed. A Nd:YAG laser of wavelength at 355 nm was used, and the beam pattern was transformed into a rectangle and a sheet beam was formed. The Raman scattered light was observed at a right angle with respect to the laser beam axis using a gated ICCD camera and an interference filter. Shadowgraph images were obtained at the same condition. The Raman scattering light image from atmospheric nitrogen was first acquired and the function of Raman scattering light acquisition and the background light suppression was confirmed. Next, images of the Raman scattering light image and shadowgraph of hydrogen gas discharged from a nozzle into the atmosphere were acquired. The two obtained Raman images were compared and the spatial concentration distribution of the flow of the hydrogen gas at different flow rates was calculated. This method is effective for visualizing the gas flow and measuring the concentration distribution of the Raman active molecules, such as hydrogen gas.

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Measurement techniques by aerial images are effective for the acquisition of spatial information. Aerial images are used for quick disaster recovery and prevention of second disaster in the time of a nature disaster. Although automatic change detection is suitable to overviewing wide-area broadly, an actual damage survey needs human interpretation of images eventually. Web Photogrammetry has been developed as a stereo view and measurement environment on a web browser. This system is enable to be used anywhere with no special knowledge and training of photogrammetry. This paper descript rapid mapping of disaster information on Web Photogrammetry.

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A way of large temperature coefficient on PTAT voltage generator is proposed. By stacking the proposed circuits, a PTAT voltage generator with large temperature coefficient can be realized. The PTAT voltage generator is analyzed by use of 4-terminal MOSFET model in subthreshold region based on the diffusion current. The temperature coefficient of measured value is compared with that of theoretical value.

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This paper discusses the analytical result of the glitch noise improvement in the multi-bit delta sigma D/A converter with Data-Weighted-Averaging (DWA). The DWA-DAC is effective for the improvement measure of SNR deterioration with element deviation. However, the DWA-DAC has the problem that the accuracy decreases by the glitch noise. The glitch noise occurs by the timing skew. So we propose to use RTZ waveform (fixed code) that is appropriate for the DWA-DAC. In this result, we obtain that the accuracy is able to improve 10dB when the timing-skew is 100ps.

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Design method of stacked NAND type FeRAM with 2-transistor type memory cell has been newly proposed. With newly introduced WL voltage generator which enables to compensate drain current variation caused by mis-alignment of the ferro-electric film removal mask 4F² small cell size has been successfully realized. 32 stage of stacked NAND type FeRAM is a promising candidate for realizing high reliability compared with the conventional stacked NAND type 1-transistor FeRAM.

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We propose Timing Group Division (TGD) for faster IEEE 802.15.4 throughput. Our proposal method splits terminals in some groups. All terminals on each group have both Timing Group Division delay and CSMA/CA delay. Terminals avoid packets collision using two kind of delays so that the system becomes faster than using only CSMA/CA system. When terminals divided into 2 groups or more, we confirmed faster communication from our actual experiment result. Our proposal method was able to communicate faster than the method using only CSMA/CA according to 16 end-devices actual experiment results, and became faster more than 40% over. Furthermore, we propose autonomously grouping method using RSSI for the autonomous decentralized network. Our proposal method using RSSI was able to faster than the method using only CSMA/CA according to actual experiment results, and became faster more than 25% over. Thus, we establish autonomously grouping method for TGD by our proposal method.

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Rate adaptation in wireless LANs is to select the most suitable transmission rate automatically according to channel condition. If the channel condition is good, a station can choose a higher transmission rate, otherwise, it should choose a lower but noise-resistant transmission rate. Since IEEE 802.11 does not specify any rate adaptation scheme, several schemes have been proposed. However those schemes provide low throughput or unfair transmission opportunities among stations especially when the number of stations increases. In this paper, we propose a rate adaptation scheme under which the transmission rate quickly closes and then stays around an optimum rate even in the presence of a large number of stations. Via simulation, our scheme provides higher throughput than existing ones and almost equal fairness.

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Retino-tectal projection is one of the pathways in visual information processing. During development, spontaneous electrical activity of superior colliculus (SC) probably plays an important role for proper network formation. In this study, SC slices were taken from new-born rats and cultured on microelectrode-array (MEA) substrates. Spontaneous activities of the cultured SC were recorded for four weeks. During the first week, most of the cultured SC slices generated sporadic spikes. These sporadic spikes gradually changed into periodic synchronized bursts. Spatially organized synchronized activity produced low frequency signals (local field potential: LFP). All of the test slices showed clear LFPs within three weeks. Large negative peaks were observed in the middle layer of the slices, while positive signals were obtained around the deep layers. Current source density (CSD) analysis revealed that middle layers acted as a current source and surface and deep layers were the sinks. These results suggested that layered structures of SC were well-maintained under the culture conditions and the cells in the middle layers played dominant roles in generating these periodic synchronized spontaneous activities.

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Deviation of driving behavior from usual could be a sign of human error that increases the risk of traffic accidents. This paper proposes a novel method for predicting the possibility a driving behavior leads to an accident from the information on the driving behavior and the situation. In a previous work, a method of predicting the possibility by detecting the deviation of driving behavior from usual one in that situation has been proposed. In contrast, the method proposed in this paper predicts the possibility by detecting the deviation of the situation from usual one when the behavior is observed. An advantage of the proposed method is the number of the required models is independent of the variety of the situations. The method was applied to a problem of predicting accidents by right-turn driving behavior at an intersection, and the performance of the method was evaluated by experiments on a driving simulator.

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This paper proposes a new online feature extraction method called Incremental Recursive Fisher Linear Discriminant (IRFLD) whose batch learning algorithm called RFLD has been proposed by Xiang et al. In the conventional Linear Discriminant Analysis (LDA), the number of discriminant vectors is limited to the number of classes minus one due to the rank of the between-class covariance matrix. However, RFLD and the proposed IRFLD can break this limit; that is, an arbitrary number of discriminant vectors can be obtained. In the proposed IRFLD, the Pang et al.'s Incremental Linear Discriminant Analysis (ILDA) is extended such that effective discriminant vectors are recursively searched for the complementary space of a conventional discriminant subspace. In addition, to estimate a suitable number of effective discriminant vectors, the classification accuracy is evaluated with a cross-validation method in an online manner. For this purpose, validation data are obtained by performing the k-means clustering against incoming training data and previous validation data. The performance of IRFLD is evaluated for 16 benchmark data sets. The experimental results show that the final classification accuracies of IRFLD are always better than those of ILDA. We also reveal that this performance improvement is attained by adding discriminant vectors in a complementary LDA subspace.

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The past recent years have witnessed more and more applications on image retrieval. As searching a large image database is often costly, to improve the efficiency, high dimensional indexes may help. This paper proposes an adaptive hybrid index (AHI) supported by a construction-and-extraction technique to support image retrieval. First, the image clusters are further partitioned into sub-clusters to reduce the overlap between clusters and indexed into an iDistance index. Then, the query sampling statistically extracts some sub-cluster from the iDistance index into a sequential file. Finally, the users' queries are accurately returned by searching both the iDistance index and the sequential file. It's proved that the proposed AHI never performs worse than the sequential scan. Particularly, the experimental results demonstrate that the proposed index AHI is beneficial and achieves better performance than some exiting methods. It is about 2 times faster than iDistance, almost three times than Omni-sequential, more than four times faster than sequential file and more than 10 times faster than M-tree on the benchmark images set. The effect of the proposed AHI is also investigated by our implemented content based images retrieval system.

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Recently, frequency-domain equalization for single-carrier transmission (SC-FDE) has been given much attention. For example, the enhanced mobile phone system, a SC-FDMA (Single-carrier frequency division multiple access) method using SC-FDE and multiple access will be adopted. However in previous research, there are many papers describing the features and advantages of SC-FDE based on a comparison of SC-FDE and orthogonal frequency-division multiplexing (OFDM) systems. In this technical note, we discuss single-carrier transmission equalization in the time-domain (SC-TDE) and SC-FDE in a unified way centered on the Wiener filter based on the minimum mean square error (MMSE) criterion. The reason to take up a Wiener Filter is that it is a basic filter based on the MMSE criterion. Also, we explain the basic principle of the SC-FDE and SC-FDMA in an organized and systematic way. Moreover, we point out the physical meaning of the Wiener solution in SC-FDE and relationship between SC-TDE and SC-FDE Wiener solutions. As a result, we show useful information and pointers, especially for when we want to replace existing SC-TDE technology with SC-FDE technology.

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The objective of this study is to assess physiological effect of the frequency of illumination in a visual search task by physiological indices. Three types of a fluorescent light were tested, which were operated with DC, high-frequency AC, and commercial AC. As a result, significant differences on central and sympathetic nervous systems' activity were confirmed depending on the types of illumination.

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This paper proposes a method for virtually trying clothes on without costly devices. The proposed method approximately acquires a deformation caused by a user's body shape from a 2D image of a marked cloth. Experiments showed the proposed method could reduce cloth size error for about a half of tested examinees.

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