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To evaluate the diameter of lightning discharge column, a unique image observation system has been developed. The system utilizes a video camera and an array of multi-wires. The wire make the shadow in the image of the light source and from the light intensity profile of the shadow the width of the light source is estimated. By using the dummy light source, good agreement has been obtained in the light intensity profile between observed and the calculated. The resolution was evaluated and found that it is one order enhanced as that evaluated from the image width. The system was successfully utilized to observe the real lightning discharges.

A new type of high-speed streak camera was developed to observe the process of lightning discharge. The camera consists of a rotating quadrate pyramid mirror and a digital video camera. Using the camera we can observe the lightning discharge in all horizontal direction and continuous observation is available without using high-speed shutter synchronizing with lightning discharge. The visual range, the time resolution and the dead time of the camera were evaluated theoretically and experimentally. From the evaluation we found that the time resolution of less than ten μs is expected at maximum rotating speed of the mirror of 200s-1. The percentage of dead time was evaluated to be less than 50%. By using the camera, we have successfully observed the lightning discharges and from the observation we have evaluated the shape, and the duration of each lightning discharge.

To improve the purity of an intense pulsed ion beams a new type of pulsed ion beam accelerator named ≪bipolar pulse accelerator≫ (BPA) was proposed. To confirm the principle of the accelerator a prototype of the experimental system was developed. The system utilizes By type magnetically insulated acceleration gap and operated with single polar negative pulse. A coaxial gas puff plasma gun was used as an ion source, which was placed inside of the grounded anode. Source plasma (nitrogen) of current density ≈25 A/cm2, duration ≈1.5 μs was injected into the acceleration gap by the plasma gun. The ions are successfully accelerated from the grounded anode to the drift tube by applying negative pulse of voltage 240 kV, duration 100 ns to the drift tube. Pulsed ion beam of current density ≈170 A/cm2, duration ≈50 ns was obtained at 41 mm downstream from the anode surface. To evaluate the irradiation effect of the ion beam to solid material, amorphous silicon thin film of thickness ≈500 nm was used as the target, which was deposited on the glass substrate. The film was found to be poly crystallized after 4- shots of the pulsed nitrogen ion beam irradiation.

Micromachined active sliders based on head load/unload on demand systems is an interesting concept technology for ultra-high magnetic recording density of more than 100 Gb/in2. The active sliders that we proposed use PZT thin films as a microactuator and control the slider flying height of less than 10 nm. It is necessary to develop high performance microactuators in order to achieve active sliders operating at very low applied voltage. This paper describes the development of novel PZT thin films for active sliders. The sol–gel fabrication process for PZT thin films is developed and the fundamental characteristics for the PZT thin films are investigated. It is confirmed that the PZT thin films have good ferroelectric properties. Furthermore, novel thin film microactuators are proposed. The feature is that the sol–gel PZT thin films (thickness 540 nm) are deposited on the sputtered PZT thin films (thickness 300 nm) fabricated on bottom Pt/Ti electrodes. Therefore, the novel thin films consist of a thermal SiO2 layer and the sputtered and sol–gel PZT thin films layers sandwiched with upper Pt and bottom Pt/Ti electrodes on a Si slider material. Fabricating the diaphragm microactuator, the piezoelectric properties for the novel composite PZT thin films are studied. As a result, the piezoelectric strain constant d31 for the novel PZT thin films is identified to be 130 × 10−12 m/V. This value is higher than conventional monolithic PZT thin films and it is found that the novel composite PZT thin films have the good piezoelectric properties. This suggests the feasibility of realizing active sliders operating at lower voltage under about 10 V.

One hundred and sixty-one patients with pulmonary metastases were studied with CT. Six of them proved to have endobronchial (intraluminal) metastatic lesions by bronchoscopy. Retrospective analysis of the CT studies showed obstruction and/or narrowing of the bronchi in 5 cases while no lesion was observed in one patient. Although CT can not always demonstrate intraluminal lesions, it should be performed when an endobronchial metastasis from extrathoracic malignancy is seen by bronchoscopy because it will show hilar or mediastinal lymphadenopathy, or single or multiple pulmonary metastases other than the endobronchial lesion.

This paper addresses the problem on digital watermarking, called the data hiding problem that refers to embedment and extraction of hidden information in a given image with the highest possible reliability. The performance of a watermarking system is measured by the probability of error for the extracted information. We present a new solution which significantly improves the performance of additive watermarking in the spatial domain. The embedment considered in this paper selects the watermarked regions randomly depending on a secret key while it fixes the watermark. We construct an optimum decoding scheme which uses the differences of luminance components in extraction. Then, we prove that the proposed decoding scheme significantly improves the performance. The theoretical results are confirmed experimentally.

A new type of pulsed ion beam accelerator named "bipolar pulse accelerator" (BPA) has been proposed in order to improve the purity of intense pulsed ion beams. To confirm the principle of the BPA, we developed a bipolar pulse generator for the bipolar pulse experiment, which consists of a Marx generator and a pulse forming line (PFL) with a rail gap switch on its end. In this article, we report the first experimental result of the bipolar pulse and evaluate the electrical characteristics of the bipolar pulse generator. When the bipolar pulse generator was operated at 70% of the full charge condition of the PFL, the bipolar pulse with the first (-138 kV, 72 ns) and the second pulse (+130 kV, 70 ns) was successfully obtained. The evaluation of the electrical characteristics indicates that the developed generator can produce the bipolar pulse with fast rise time and sharp reversing time.

The paper presents a novel system to asses quickly the direction of thunderstorm by using a few field mills on the ground. As opposed to traditional methods using expensive radar systems to detect thundercloud movement, the presented method simply uses the electric waveforms detected by the field mills and, by using a neural network of suitable complexity, can determine the thundercloud's direction with reasonable accuracy. The neural system is trained with data obtained from the simulation of thundercloud dynamics using parameters observed through experiments. Through extensive testing, it is found that the presented system can reasonably track the direction of the thunderstorm as it propagates while dynamically changing its parameters, and, thus, offers the possibility of creating a practical system. Two types of neural networks are developed and their efficiencies compared.

To examine the effects of single and long-term administration of wheat albumin (WA) on blood glucose levels and blood glucose control, respectively.Randomly arranged crossover trial for single administration in healthy subjects and double-blinded randomized controlled trial for long-term administration (3 months) in diabetic patients. In vitro alpha-amylase inhibitory activity of WA was also determined.Central Research Laboratories of Nisshin Flour Milling Co. Ltd. (Saitama, Japan) for single administration and Aiwa Clinic (Saitama, Japan) for long-term administration.A total of 12 healthy adult male volunteers for the single administration and 24 type II outpatient diabetics with mild hyperglycemia for the long-term administration.Subjects took soups containing 0, 0.25, 0.5, and 1.0 g WA before test meals for single administration, and patients took soups with or without 0.5 g WA before every meal for the long-term (3 months) administration.In vitro alpha-amylase inhibitory activity of WA was 150 times that of wheat flour. In the single administration experiment, WA suppressed peak postprandial blood glucose levels in a dose-dependent manner: 31, 47, and 50% reduction after 0.25, 0.5, and 1.0 g administrations, respectively. In the long-term administration, 0.5 g of WA did not affect fasting blood glucose levels, whereas it reduced hemoglobin A1c levels. No significant adverse effects such as hypoglycemia or gastrointestinal disturbances were observed in the two experiments.In the treatment of type II diabetic patients, WA might be a useful functional food, which, with diet and exercise, could help to improve blood glucose control without any critical adverse effects.

Intense pulsed ion beams (PIB) are expected to be applied. for pulsed ion beam implantation to semiconductor since an anneal-less implantation process is expected. In the application the purity of the ion beam is very important, however, the purity of conventional PIB is very poor. To improve the purity a new type of PIB accelerator named "bipolar pulse accelerator (BPA)" is proposed. The accelerator consists of two acceleration gaps (first gap and post acceleration gap) and a drift tube placed between the gaps. High power bipolar pulse is applied to the drift tube to accelerate ions. In the accelerator intended ions are selectively accelerated and the purity of the ion beam is enhanced. As the first step of the development of the accelerator, magnetically insulated acceleration gap is developed. The gap has an ion source of coaxial gas puff plasma gun on the grounded anode and a negative pulse is applied to the cathode to accelerate ions. By using the plasma gun, ion source plasma (nitrogen plasma) of current density around 100 A/cm/sup 2/ is produced, which is injected to the anode. After the plasma injection, negative pulse of voltage 220 kV, duration 60 ns is applied to the cathode. In the paper, preliminary results of the experiment are described including the waveforms of the system and shadowgraph measurement. From the results principle of the acceleration of ion beam in the BPA is confirmed.

Two types of electrostatic linear accelerators (type A and B) are proposed as a substitute for an induction linac to accelerators a high current pulsed ion beam. In type A sufficiently long acceleration tubes compared to the ion beam is used, inside of which multi-stage acceleration gaps are placed. Square pulses are sequentially applied to the acceleration gaps where the beam is passing and compensating voltages are applied to the gaps where the beam is absent to realize multistage acceleration without increasing the beam potential. On the other hand, in type B, bi-directional pulses are utilized which are sequentially applied to the acceleration gaps to realize the multistage acceleration. Compared to ion beam induction linacs, the proposed accelerators are simple, low cost and a higher acceleration gradient is expected since magnetic cores or induction cells are not utilized. Electrical behaviors of both systems are numerically simulated and demonstrated. In addition, two types of pulse forming lines are proposed to produce bi-directional pulses for the type B accelerator. The performance of the lines was demonstrated numerically and experimentally.

In this paper, a new digital watermarking method for vector maps is proposed, where the watermark can be embedded in a set of polylines by using the discrete Fourier transform (DFT). The robustness against external attacks and visual degradation caused by embedding were evaluated, and the effectiveness of the watermarking was confirmed. Our watermarking method is especially robust against vertex reordering attacks and noise imposition on the vertex coordinates.

Summary form only given, as follows. Intense pulsed heavy ion beam (HIB) is expected to be applied for pulsed ion implantation to semiconductor since anneal-less process is expected. In the application the purity of the ion beam is very important. However, since the purity of HIB produced in the conventional pulsed power ion diodes are usually very poor and they are not possible to be used in those applications. To improve the purity of the ion beams new type of pulsed power ion accelerator is proposed. The concept of the accelerator is shown in the figure. The accelerator consists of two acceleration gaps (an ion source gap and a post acceleration gap) and a drift tube and a bipolar pulse is used to accelerate the ion beam. In the accelerator purity of the ion beam is expected to be enhanced. As the first step of the development of the accelerator, the characteristics of Br-type magnetically insulated diode was evaluated, which will be used as the 1st gap of the accelerator. An active ion source of carbon plasma gun and a surface flashover ion source were used in the diode. The ion current density, ion species, energy spectrum were evaluated by a Thomson parabola spectrometer, filtered ion pinhole camera, biased ion corrector. In the paper, the result of the experiment is described with the principle and the design concept of the proposed accelerator.

To improve the purity of the ion beams new type of pulsed power ion accelerator named “bipolar pulse accelerator” was proposed. The accelerator consists of two acceleration gaps (an ion source gap and a post acceleration gap) and a drift tube, and a bipolar pulse is applied to the drift tube to accelerate the beam. In the accelerator intended ions are selectively accelerated and the purity of the ion beam is enhanced. As the first step of the development of the accelerator, a Br-type magnetically insulated acceleration gap is developed. The gap has an ion source of coaxial gas puff plasma gun on the grounded anode and a negative pulse is applied to the cathode to accelerate the ion beam. By using the plasma gun, ion source plasma (nitrogen) of current density around 100 A/cm2 is obtained. In the paper, the experimental results of the evaluation of the ion beam and the characteristics of the gap are shown with the principle and the design concept of the proposed accelerator.

To apply an intense pulsed ion beams produced in plasma focus (PF) to material processing, characteristics of the beam was evaluated. In the experiment a Mather type PF was used which was pre-filled with N 2 (5.5 Pa) to produce nitrogen ions. To clarify the mechanism of the production of impurity ions, two types of anode (type A; rod type and has an anode tip on the top, type B; hollow shape top) were used. In both type peak discharge currents of 550 kA were obtained at 1.5 µs after the rise of the current. From the measurement by Thomson parabola spectrometer large quantity of copper ions were observed when type A is used and the purity for type A and type B were evaluated to be 26 % and 90 %, respectively. To enhance the energy and the charge state of the nitrogen ions the PF with type B anode was pre-filled with mixture of nitrogen and hydrogen (N 2 20, H 2 180 Pa). From the TPS measurement, multiply ionized nitrogen ions (N1−5+) of energy more than several MeV were observed with protons of maximum energy 1 MeV. Thin layer of amorphous silicon was irradiated by the ion beams produced in PF and we found that the layer was crystallized.

The characteristics of the ion beams produced in a plasma focus device were studied. In the experiment, a Mather-type plasma focus device was used which was prefilled with H2 at 2.3 Torr. Ion species and their energy spectra were evaluated with a Thomson parabola spectrometer. The particle pinhole image was obtained with an aluminum filtered particle pinhole camera. The ion current density was measured with a biased ion collector. From the measurement, the proton beam energy was found to be distributed from 0.15 MeV to 2 MeV. The particle pinhole image of the proton beam with an energy of more than 1 MeV has spotlike patterns. The ion current density of 2400 A/cm2 with a pulse width of 50 ns was observed on the axis at z=260 mm from the top of the anode. The peak power brightness of the proton beams was evaluated to be 18 GW/cm2/sr/keV, and the total power brightness was evaluated to be 20 TW/cm2/sr.

A new method was developed to differentiate the upper lobe from the middle lobe of the right lung with thin-section, high-resolution computed tomography. In the upper lobe, a medial subsegmental bronchus of an anterior segmental bronchus is always located lateral to the corresponding artery. In the middle lobe, a medial subsegmental bronchus of a lateral segmental bronchus and a superior and inferior subsegmental bronchus of a medial segmental bronchus are always located medial to the corresponding artery. In other words, the anatomic relationship between the subsegmental bronchi and the corresponding pulmonary arteries in the upper lobe is opposite to that in the middle lobe. One hundred seventeen cases, including 54 cases of lobar volume loss, were reviewed with this method, and in each case it was possible to differentiate the upper lobe from the middle lobe without the contiguous section analysis.

A new channel-doping technique for high-voltage depletion-mode double-diffused MOSFET (DMOSFET) is demonstrated. The technique that is used is channel doping performed at the surface of the laterally diffused body region in a self-aligned manner. Decrease of the breakdown voltage due to decrease of the threshold voltage is successfully prevented by using the new technique. A 1050-V DMOSFET was experimentally fabricated with a negative threshold voltage of -2 V.