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Object detection plays an important role in autonomous driving systems. LiDAR is widely used in autonomous driving vehicles and robots as a sensor for environmental perception. Recently, the development of computational power and deep learning technology makes it possible to classify and locate objects from LiDAR point cloud in a single end-to-end learnable network. However, objects are sparsely distributed in large point cloud field, and are always been partly scanned by LiDAR, which pose a challenge for accurate and rapid object positioning and classification from the raw point cloud. In this paper, we introduce a new single-shot refinement neural network for fast and accurate 3D object detection from the raw LiDAR point cloud. Firstly, we exploit self-attention mechanism in main object detection branch to enhance object feature representation. Secondly, we apply deformable convolution for learning adaptive receptive fields to fully capture the features of rotating and partially visible objects. Thirdly, an object refinement branch is introduced to produce a finer regression of objects upon the primary estimation from the main detection branch. All proposed modules have been proven to effectively improve the accuracy of object detection. Our method is evaluated on KITTI 3D detection benchmark and achieves state-of-the-art results while maintains real-time efficiency. Furthermore, real-time test in autonomous driving vehicle demonstrates that our method is robust to 16 channels LiDAR and can meet the demands of accuracy, efficiency, and visibility of object detection in various urban scenarios.

To evaluate hematological effects of direct current (DC) and alternating current (AC) extremely low frequency (ELF) electric field exposure, this study investigated red blood cell (RBC) movement in whole blood. Video images of RBCs were recorded under a microscope using specially designed electrode systems. Video analysis software was then used to measure the RBC velocity. The noise level and measurement system stability were confirmed based on results of a no-field exposure experiment. Using the electrode system to produce a non-homogeneous electric field, different movements were found to occur in DC and AC field exposure. The RBCs moved in the directions of the electric field and the gradient of field distribution, respectively, in the DC and AC fields. Dependences of the RBC velocity on the field strength were, respectively, linear and quadratic in the DC and AC fields. These results suggest that electrophoretic and dielectrophoretic movements were, respectively, dominant in the DC and AC fields. The magnitude of the electric field necessary to cause these effects was found to be 10

Using near-infrared (NIR) light with 700–1200 nm wavelength, transillumination images of small animals and thin parts of a human body such as a hand or foot can be obtained. They are two-dimensional (2D) images of internal absorbing structures in a turbid medium. A three-dimensional (3D) see-through image is obtainable if one can identify the depth of each part of the structure in the 2D image. Nevertheless, the obtained transillumination images are blurred severely because of the strong scattering in the turbid medium. Moreover, ascertaining the structure depth from a 2D transillumination image is difficult. To overcome these shortcomings, we have developed a new technique using deep learning principles. A fully convolutional network (FCN) was trained with 5,000 training pairs of clear and blurred images. Also, a convolutional neural network (CNN) was trained with 42,000 training pairs of blurred images and corresponding depths in a turbid medium. Numerous training images were provided by the convolution with a point spread function derived from diffusion approximation to the radiative transport equation. The validity of the proposed technique was confirmed through simulation. Experiments demonstrated its applicability. This technique can provide a new tool for the NIR imaging of animal bodies and biometric authentication of a human body.

Introduction Stress-related disorders, such as depression, psychosomatic disorders and anxiety neurosis, are common and increasing in the workplace. Aromas have ataractic and sedation effects on the parasympathetic nerves. They also affect the feelings of fatigue from stress by stimulating the central nervous system. The purpose of this study is to examine the effect of an olfactory stimulus on changes in a physiological index. Using aromas during the loading of stress, we measured beat-to-beat interval (R-R interval) times from electrocardio-gram (ECG) recordings. Methods The subjects in our study were 3 male medical university students (subjects’ codes were A, B and C). After assuming a relaxed seated position for 10 min, the subjects performed a mental arithmetic task for 60 min followed by relaxation for 30 min, and then a rest for 10 min. The mental arithmetic task is a method of adding numbers without using tools. Every subject performed both the control-load and aroma-load tests under the same protocol, while the ECG was measured. They smelled lavandula angustifolia during the aroma-load. Result We analysed the power spectrum of high and low frequencies. The P1 (low frequen-cy)/P2 (high frequency) was defined as the ratio of P1 to P2. There was no change in the P1/P2 of 2 out of 3 subjects by using the aroma. Subjects A and B could avoid mental stress by using the aroma during the mental arithmetic operation. Discussion In an analysis of the power spectrum in the R-R interval times, the high and low frequencies in the physiological index of stress loading suggest that the aromas have an effect on the autonomic nervous system. As the strain on sympathetic nerve was relaxed, we conclude that the aroma affected the sympathetic nerves. Thus, we conclude that the aroma affected a sympathetic nerve, relaxing the strain on it.

Insulation tests for the stator coil, which decides the motor life, are carried out once several years in power and industrial plant. In the case of high voltage (HV) motors, insulation failure may adversely affect plant operation. Hence, maintenance activities, including insulation tests, research on insulation deterioration, and online Partial Discharge (PD) monitoring, are actively pursued for HV motors.On the other hand, the maintenance of low voltage (LV) motors is restricted to breakdown maintenance (BDM) because (1) a large number of LV motors are in operation in plants and (2) maintenance activities are relatively more expensive than those for HV motors. In this paper, the results of a study on insulation deterioration detection for LV motors are presented. For the deterioration detection, the deference in Zero-Sequence current waveforms between normal conditions and fault conditions is analyzed. This method helps in decreasing the maintenance cost and in online insulation diagnosis for LV motors.

We propose a multielectrode circular position-sensitive device that does not have any discontinuity in the detection region and has multiple electrodes for current output. We have also manufactured a prototype device. The device has a circular detection region that consists of photodiodes radially aligned with regular pitch and a resistance line connecting the outer edges of the photodiodes. All of the photocurrent excited in the photodiodes flows into the resistance line and is extracted from the electrodes connected to the resistance line at even intervals. There is no insensitive region for current output in this device since the detection region and the resistance line are separated; thus, detection with high resolution is possible at every angular position. We conducted a simulation of the detection characteristics and will propose a computational method for the position that uses four-electrode outputs in this paper. We confirmed that it is effective in minimizing the error from both the simulation and the experiment. We will also propose a measurement system of absolute angle using this method, confirming an error of less than 0.1° in the computation results.

When the rectangular slit of an optical encoder projects an image, the containment of higher-order components in the projected image depends on the gap distance. Therefore, we performed the Fourier series expansion of the function describing Fresnel diffraction pattern to obtain a simple relational expression that can show the relation between the gap distance and the containment of each order component and then carried out an experiment to verify the obtained expression. Using this expression, we found that certain orders of the wave components disappear depending on the slit opening ratio and also that the use of a slit with an opening ratio smaller than 0.5 results in lesser distortion of the waveform over a wide range of gap values. Reduction of waveform distortion over such a wide range can prevent increment of errors caused by shaft displacement in the axial direction and assembly errors. Thus, robust performance of the encoder can be achieved. The results of this study are expected to be useful in the design of robust optical encoders.

We have developed a novel evaluation technique of the deterioration degree of insulators for breakers using a chemical analysis and the Mahalanobis–Taguchi (MT) method. It is possible to evaluate the deterioration degree with great accuracy and nondestructively on-site by this technique without the effect of humidity and external noise such as electromagnetic waves. The mechanism of the insulator's surface resistivity reduction was clarified, and it was found that the deterioration degree of insulators could be evaluated by this technique because a linear relationship existed between the results judged by the MT method and the actual measurement results for the surface resistivity. In comparison to electrical methods, such as partial electric discharge and megohmmeters, the evaluation accuracy has been improved by three digits and the range of the deterioration degree that could be evaluated was expanded by seven digits. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 168(1): 11–20, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20849

The authors have developed a remaining service life diagnostic technology for insulators, which are important parts involved in determining the service life of power distribution equipment. Application of chemical evaluation and the Mahalanobis–Taguchi (MT) method enabled them to diagnose the insulators' degree of deterioration with great accuracy and nondestructively onsite. The theory derives the threshold value of surface resistivity for electric discharge initiation calculated based on the diagnostic results from the MT method and the year in which the master curve of service life and the threshold value intersect. It was clarified that a remaining service life could be predicted by this technology, because there was a good relationship between the check examination results of electric discharge initiation in the laboratory and the results the authors found. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 167(2): 1–9, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20854

A new type of circular semiconductor position sensitive detector (PSD) called multi electrode circular PSD (ME-CPSD), which consists of a photosensitive region, a resister line, and 16 electrodes, is presented. The photosensitive region is in the shape of a ring, which is formed by the radial arrangement of long and narrow photodiodes. The outer ends of the photodiodes are connected to the continuous resistor line. Photoexcited carriers generated in the photodiode flow to the resistor line and are extracted by the multi electrode, which divides the resistor into 16 equal parts. The angular position of the light spot is calculated from the output current of the selected electrodes. Compared to conventional circular PSDs, the reliability of angular measurement is better, this is because the ME-CPSD does not have an undetectable region caused by unavoidable discontinuities in the structure of conventional circular PSDs. This device can not only measure the absolute angular position but also carry out a more precise angular measurement by selecting narrower electrode intervals. This device has the capability of realizing a high-precision noncontact angular measurement system with a simple construction.

We developed remaining service life diagnostic technology of phenol insulators for circuit breakers. Phenol insulators were analyzed by chemical evaluation such as ion concentration and coloration, and the results were diagnosed by the Mahalanobis-Taguchi system (MTS), which is a pattern information technology. Particularly effective items for diagnosis included ions of nitric acid, sulfuric acid, chloride, and calcium. Since there was a good relationship between the results diagnosed by MTS and the actual measurement results of surface resistivity, we found that applying MTS to the chemical evaluation results allowed deterioration diagnosis of phenol insulators instead of surface resistivity, which couldn't be measured on-site. Time was defined as the end of the service life when electrical discharge was initiated and remaining service life was predicted. The linear relationship (master curve of service life) was clarified between the real number value of elapsed time and the logarithmic value of surface resistivity at 50% RH, and remaining service life was predicted from the diagnosis results by MTS and the year in which the master curve and the threshold value intersect. Surface resistivity (threshold value) for electrical discharge initiation was derived from creepage distance, permittivity of phenol insulators, frequency, etc. We substantiated that the remaining service life of the phenol insulators could be predicted by this technology because a good relationship existed between the check examination results of the electric discharge initiation in the laboratory and the prediction results.

We developed deterioration diagnosis technique for bus Joint in Switchboards. Increase of contact resistance by deterioration of a bus joint causes a temperature rise. However, it is difficult to really measure a temperature rise by a minute change of contact resistance. That is a method to detect a change of contact resistance of a bus joint as a temperature fluctuation. We expect that a serious accident such as a short circuit is prevented beforehand by this technique.

In this paper, by using the Android mobile terminal, we make a application of performing autonomous driving control small electric car as the target. Small EV car (COMS) is treated as experimental subjects. This application will help the Elderly, driving poor people, fast, accurate to park the car and call the car coming for users easily. Moreover, it is also considered that it becomes possible to inform the vehicle information for users. For this study, it introduce that how making the communication system with the car. Also using Map management tool “Mapinfo” for design the path for a small electric vehicle, for example the path to/from parking place. On top of that, we seek a control method to safely autonomous driving on the basis of the data around the vehicle. Also for other cars and pedestrians traveling the parking lot, we aim to correspond to the safety and smooth.

Most switchboards are used for a long term of about 30 years. As for the switchboard, the situation of the use and maintenance is individually and greatly different. So the life-expectancy presumption technique of the switchboards has not been established. We executed the deterioration diagnosis for the switchboards that had been used for 30 years. We paid attention to the surface deterioration of the insulation materials that is the main element that decides the life-expectancy of the switchboards. We evaluated the life-expectancy presumtion technique of aged switchboards based on MTS (Mahalanobis Taguchi system) method. This technique attracts attention in recent years. And we confirmed the presumption result was corresponding to the result of the verification with temperature controlled bath actually.

Information technology is increasingly important in recent years for the development of our society. IT has brought many changes to everything in our society with incredible speed. Hence, when we investigate R & D themes or plan business strategies in IT, we must understand overall situation around the target technology area besides technology itself. Especially it is crucial to understand overall situation as time series to know what will happen in the near future in the target area. For this purpose, we developed a method to generate Multiple-phased trend maps automatically based on the Internet content. Furthermore, we introduced quantitative indicators to analyze near future possible changes. According to the evaluation of this method we got successful and interesting results.

A stacked CdZnTe semiconductor detector, which is able to detect the 6.13 MeV γ-rays from 16N, was prototyped and the response calculation was carried out by a Monte-Carlo simulation. The detector response was simulated by using the electron and photon transport code, EGS4 and taking into account the carrier trapping phenomena. The results of the response calculation agreed with the experimental data from the checking source of 137Cs and 60Co. The prototype's response and sensitivity to 16N were calculated by simulating an incident energy of 6.13 MeV . The source spectra were unfolded with the detector's response function obtained by simulation, and it indicated that the incident γ-ray energy and its intensity ratio was identified. We have acquired the potential to measure the γ-ray energy in the high energy region about 6 MeV with the stacked CdZnTe detector.

The prototype model of the stacked CdZnTe semiconductor detector, which is able to measure the 6.13MeV γ-ray from 16N, was fabricated. The prototype's response calculation was carried out by Monte-Carlo method. The result of the response calculation agreed with the experiment data of check sources of 137Cs and 60Co, and 16N which was measured at vicinity of the primary cooling water pipe of the nuclear reactor. The source spectra were unfolded with detector's response function obtained by simulation, and it is indicated that the incident γ-ray energy and its intensity ratio was identified and that the energy of 6MeV γ-ray could be measured by the prototype of the stacked detector.

Gas-insulated switchgears (GIS) are important equipment in electric-supply stations where advanced techniques for safety and maintenance are required. As a result, a system is being developed that can automatically monitor and diagnose a GIS in service. This article focuses on some problems concerning insulating functions of GIS to discuss a method of signal processing for partial discharge detection and position identification. For sensors, potential detectors were installed on flanges of the GIS. Focusing on the potential fluctuations measured by these detectors, an autoregressive model is designed for potential fluctuation in a state without any partial discharge. This model is called a normal state model. The difference was found between potential fluctuations measured during partial discharge and those of the normal state model. The index of whiteness test method of the residual random process is a useful parameter for representing this difference, and the use of this method allowed detection of partial discharge that could not be found at normal potential levels. These results indicate bright prospects for manufacturing a monitoring system that can detect deterioration in GIS insulation with a high sensitivity in an early stage and that also operates on-line.

The aim of this paper is the development of a bridge diagnosis system for daily bridge maintenance. The system includes the technology of wireless sensor network, signal processing, and structure analysis of a bridge. We collect the vibration data caused by external force such as wind pressure, running vehicles and etc through wireless sensor network and then use independent component analysis (ICA) and spectral analysis to analyze the data for extracting character frequency. The diagnosis technology is developed to understand the phenomena like deterioration and corrosion of a bridge through the measurement result. So the diagnosis system can evaluate the health condition of a bridge and conduct a comprehensive deliberation on repair and reinforcement work. We apply this diagnosis system to field experiments at Kokura, Kitakyushu city in Japan and successfully extract the character frequency of a bridge.

This paper focuses on maintaining a bridge's safety by developing a daily management system. And the purpose of this study is the development of the health monitoring system. It supports the maintenance by using sensor network and Independent Component Analysis (ICA) when there are some troubles in a bridge. The result of this study brings out the vibration behavior of the overall structure in a bridge. This vibration is caused by the external force such as wind pressure, and running vehicle. The character frequency was extracted from the analysis result using ICA and Spectral Analysis. Even if the vibration behavior caused by external force is very small in the bridge, ICA can detect the vibration response from the bridge. The actual sensor network system has been developed and the performance is demonstrated.

We have applied a remaining service life diagnostic technology to phenol insulators of power distribution equipment. Application of chemical evaluation and the Mahalanobis-Taguchi (MT) method enabled us to diagnose the insulators' degree of deterioration with great accuracy and nondestructively on-site. Time was defined as the end of service life when electrical discharge was initiated and a remaining service life was presumed from the diagnostic results by the MT method and the year in which the master curve of service life and the threshold value intersect. Surface resistivity (threshold value) for electrical discharge initiation can be calculated from creepage distance, permittivity, frequency, etc.. It was clarified that a remaining service life for phenol insulators could be presumed by this technology because there was a good relationship between the check examination results of electric discharge initiation in the laboratory and the presumption results.

In order to reinforce the research development power in the software-related sectors, it is necessary to clarify the methodology of formulating the R&D strategies. This paper focuses on the methodology of setting the themes for R&D. In order to promote R&D more effectively, we propose the NeXT model which consists of two stages: forecasting the priority areas based on the conflicts between near-future trends and verifying the priority areas. We have evaluated this methodology by comparing with the results of the 7-th Technology Foresight which was conducted using the Delphi method. The NeXT model comes in compliance with the characteristics of the current society in which the link between technology and society is stronger than ever before, and is applicable to a wide range of fields.

This paper focuses on maintaining a bridge's safety by developing a daily management system. And the purpose of this study is the development of the health monitoring system. It supports the maintenance by Independent Component Analysis (ICA) when there are some troubles in a bridge. The result of this study brings out the vibration behavior of the overall structure in a bridge. This vibration is caused by the external force such as heavy weight impact, wind pressure, and running vehicle. The character frequency was extracted from the analysis result using ICA and Spectral Analysis. When the vibration behavior caused by external force is very small in the bridge, ICA can detect the vibration response from the analysis result. Therefore, it is proved that the potential of detection was high by ICA.

In business or technology planning, it is strongly required to grasp the overall technology trends and predict what will happen in the near future. In this paper, we propose the method where we can detect and analyze the technology trends from the Internet resources.

A degradation diagnosis method that detects the degradation symptoms of electronic cards earlier and with higher sensitivity than previous techniques is presented. One type of degraded IC is obtained experimentally by applying a low surge voltage. For the case of the op-amps, there exists a quantitative relation between the degradation of the IC predicted from the increasing off-set current and the correlation with output noise. The root-mean-square value of the noise is an effective index of degradation detection. A method based on a measurement of the minimum value of supply voltage necessary to maintain the correct logical operation is effective in detecting degraded TTLs. An automatic instrument for degradation detection of electronic cards is developed, and its effectiveness is verified. >

Publisher Summary This chapter discusses the method of distinguishing the noises accumulated in the sensors at the time of radiation measurement from the signals. The study is confined to the noises and signals observed by the sensors. The types of these sensors are NaI scintillator, plastic scintillator, and Geiger–Mueller counter tube. As for the signal observed in each sensor, the waveform of voltage above a certain level is counted as a pulse signal. The voltage levels to be counted are given in every characteristic of sensor type, with the minimum voltage being NaI scintillator 0.3 V. More than 66.7% (0.2 V) of this voltage is subjected to analysis. There is no theoretical ground for determining the minimum voltage as a subject of analysis; the decision has been made entirely on the basis of experience. Furthermore, because voltages above 5.0 V are not feasible, any voltage above this level is discarded as a pulse signal. As for the negative voltage, it is not counted as a pulse signal, and therefore it is exempted from detailed study. However, signals below -0.2 V level will undergo a brief analysis to get their existence made clear. The surge waveform with pulse width below 10 ns is also excluded from the subject of analysis, because the counter fails to react to such short-time pulse signals because of their frequency characteristics.

To reinforce the research development power, it is necessary to clarify the methodology of formulating the R&D strategies. This paper focuses on the methodology of setting the themes for R&D. We propose the NeXT model, which consists of two stages: foresight of the priority areas based on the conflicts between near-future trends and verifying the priority areas. We show a method for calculating a Degree of Conflict using FURPS+ model. The NeXT model comes in compliance with the characteristics of the current society in which the link between technology and society is stronger than ever before.

Out-of-pile experiments were carried out to study the feasibility of the local sodium boiling detection by use of temperature, flow and acoustic noises. The studies showed that the temperature fluctuation transferred the information of local sodium boiling to the end of the bundle, but little to the outlet. A new anomaly detection method, which used the algorithm of whiteness test of the residual time series data of autoregressive model, especially using flow fluctuation, was effective detecting the anomaly such as local sodium boiling. On the other hand, acoustic noises with local sodium boiling became much higher than the background such as the mechanical and flow noises. A waveguide method, which was utilized for the present experiments, was useful for the boiling detection.

A technique to estimate the reduced scattering coefficient from spatially resolved backscattered light was developed using the solution of diffusion approximation. However, the diffusion approximation is valid in a scattering-dominant case. An exact solution for the reduced scattering coefficient was newly obtained using the special modification factor, which expands the applicability of the diffusion approximation to the case of absorption media such as the human blood. The validity of the simulation and the applicability of the proposed technique were verified with measurements using tissue and blood-simulating turbid media.