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This correspondence presents a development of hybrid electric field meter methodology. This particular field meter can simultaneously measure the vertical and horizontal electric fields of the thundercloud. The additional horizontal electric field provides the useful information of the direction of thunderclouds. The capability of the apparatus was experimentally evaluated and has been confirmed that it has the satisfactory sensitivity to both components of electric field. Additionally, an instance of observation results of the cloud-to-ground and ground-to-cloud lightning discharge has been presented.

We analyze the experimental data for ϕ → f 0 ( 980 ) γ , ϕ → a 0 ( 980 ) γ , f 0 ( 980 ) → γ γ and a 0 ( 980 ) → γ γ decay widths in a framework where f 0 ( 980 ) and a 0 ( 980 ) are assumed to be mainly q q q ¯ q ¯ low mass scalar mesons and mixed with q q ¯ high mass scalar mesons. Applied the vector meson dominance model (VDM), these decays amplitudes are expressed by coupling parameters B describing the S ( q q q ¯ q ¯ scalar meson)– V (vector meson)– V (vector meson) coupling and B ′ describing the S ′ ( q q ¯ scalar meson)– V – V coupling. Adopting the magnitudes for B and B ′ as ∼ 2.8 GeV −1 and ∼ 12 GeV −1 , respectively, the mixing angle between a 0 ( 980 ) and a 0 ( 1450 ) as ∼ 9 ° , and the mixing parameter λ 01 causing the mixing between I = 0 q q q ¯ q ¯ state and q q ¯ state as ∼ 0.24 GeV 2 , we can interpret these experimental data, consistently.

This paper presents a three-dimensional lightning discharge mapping system using arrival-time difference of broadband VHF electromagnetic pulses (20–200 MHz) methodology. The system consists of four circular plate antennas; three of which are placed to form two perpendicularly crossed-short base lines, with the fourth located at some distance. The directions of the electromagnetic radiation sources are determined using perpendicularly aligned antennas whereas the 3-D positions are obtained using all the four antennas. Broadband pulses arrival time differences are estimated incorporating time-domain signal analysis and the least-squares error method is applied to the detected broadband pulses to estimate the time delay with the quadratic interpolation technique utilized to achieve the resolution less than 1 ns. In this paper, the implementation of the system along with the successful reconstruction of the lightning discharge progression in 2-D and 3-D space is described. Additionally, instances of observation results of the cloud-to-ground and ground-to-cloud lightning discharge have been presented.

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.

Following the re-establishment of the \sigma(600) and the \kappa(900), the light scalar mesons a_0(980) and f_0(980) together with the \sigma(600) and the \kappa(900) are considered as the chiral scalar partner of pseudoscalar nonet in SU(3) chiral symmetry, and the high mass scalar mesons a_0(1450), K^*_0(1430), f_0(1370) and f_0(1710) turned out to be considered as the L=1 q\bar{q} scalar mesons. We assume that the high mass of the L=1 q\bar{q} scalar mesons is caused by the mixing with the light scalar mesons. For the structure of the light scalar mesons, we adopted the qq\bar{q}\bar{q} model in order to explain the "scalar meson puzzle". The inter-mixing between the light scalar nonet and the high mass L=1 q\bar{q} nonet and the intra-mixing among each nonet are analyzed by including the glueball into the high mass scalar nonet., Comment: 16 pages, 5 figures

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.

Recently, a greater demand for stable supply of electric power has resulted from a higher standard of living. It becomes important that the causes and locations of ground faults in distribution lines be found early and defects be repaired as soon as possible. Therefore, a unit for recording the waveform I0 of ground fault's current and the waveform V0 of its voltage is installed in distribution substations. The establishment of a technology to distinguish fault causes automatically is being hastened. This paper presents a new classification method for ground fault waveforms, based on phase-plane trajectories for the current or voltage and their differential values. Examinations of ground fault waveforms based on real data show that the waveform of current I0 is more suitable than that of voltage V0 for the classification of waveforms at ground faults and that the trajectory of each of the three types of waveforms, such as sine waves, trapezoidal waves, and spikes, has all of the characteristics in its figure. It is also found from the distribution of 167 sampling points on the phase plane that any waveforms at a real ground fault may be classified into three characteristic point distributions, which gives the possibility of easy display for the classification of ground fault causes. © 1998 Scripta Technica. Electr Eng Jpn, 122(1): 8–16, 1998

We discuss the light-pseudoscalar-meson system and try to establish assignments for the various η(≈1400−1500) states found in recent experimental searches. Assuming a mixing model with ground-stateN andS basis states and a glueball basis stateG0, we fit data for the decays J/ψ→VP and J/ψ→γP and find that the physical glueball state ι is relatively pure, with a larger non-strangeN component thanS. Of the two states η(1420) and η(1490) we prefer the lower as a glueball, since the η(1490) does not have a strong ηππ coupling, which we expect for the glueball state ι. We also conjecture that the higher mass state η(1490) is a partner of the radially excited isospin zero state η(1295).

SUMMARY A method is presented for fitting a piecewise cubic polynomial to a sequence of geomagnetic data which contains oscillations such as Pi2 pulsations superposed on rapid background changes such as bay-type disturbances. The first step of smoothing is performed by a one-pass method with a piecewise cubic polynomial where the polynomial pieces are calculated as the data is scanned only once from left to right. The knots of the approximating piecewise cubic polynomial are determined successively using a modified Powell criterion which has a free parameter μ determining the degree of smoothing. As μ grows large, the approximating function becomes smoother and the oscillations with longer periods can be separated (μ= 1 corresponds to the original Powell criterion). If a rapid background change needs to be preserved in the smoothed data, the sum of squares of residuals is locally minimized in the neighbourhood of the rapid change as the second step. The proposed method which involves two steps is capable of separating the oscillations from the rapid background changes. Some examples of good separation are displayed.

The puzzle of scalar mesons is studied by considering the gluon effects on the masses of mesons and the mixing of scalar nonet with a glueball. The f0(1300) mass is raised to ∼1300 MeV by the gluon effects while retaining itsN-like character. The f0(975) may be a 0++ glueball which mixes with the f0(1300) appreciably.

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 toxicity and therapeutic effect of the ventriculolumber perfusion of 3-[(4-amino-2-methyl-5-pyrimidinyl)methyl-1-1(2-chloroethyl)-1-nitros our ea hydrochloride (ACNU) against subarachnoid dissemination of gliomas were studied. Twenty-one patients (6 patients with anaplastic glioma, 7 with glioblastoma and 8 with medulloblastoma or PNET) received ventriculolumber perfusion of ACNU when they were diagnosed as having subarachnoid dissemination. The course of perfusion and cumulative dose of ACNU was 10 times and 95 mg on average, respectively. Most of the patients received systemic chemotherapy in combination with perfusion therapy and some patients with radiotherapy. Response rate was 17% and median survival time after the diagnosis of dissemination was 12 months for anaplastic gliomas, 29% and 12 months for glioblastoma, and 88% and over 25 months for medulloblastoma and PNET. The ventriculolumber perfusion of ACNU was performed for prophylactic purpose in 7 patients with high risk at the early postoperative period in combination with conventional adjuvant therapy. The course of perfusion and cumulative dose of ACNU was 2.3 times and 21 mg on average, respectively. One patient developed subarachnoid dissemination and died 22 months after surgery. Other 6 patients survived without dissemination on median over 29 months after surgery. Side effects encountered were headache in 4 patients, nausea and vomiting in 5, a convulsion in 2, right facial weakness in 1, fecal incontinence in 3 and meningitis in 2. They were all temporary except for facial weakness occurred in one patient. These data suggest that the ventriculolumber perfusion of ACNU is a safe and useful in the treatment and prophylaxis against the subarachnoid dissemination of gliomas.

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.