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51.
SF6 gas has excellent dielectric strength and interruption performance. For these reasons, it has been widely used for gas‐insulated switchgear (GIS). However, use of SF6 gas has become regulated under agreements set at the 1997 COP3. Thus, investigation and development for GIS with a lower amount of SF6 gas are being carried out worldwide. Presently, SF6‐free GIS has been commercialized for the 24‐kV class. Air or N2 gas is used as the insulation gas for this GIS. On the other hand, SF6‐free GIS has not been commercialized for the 72‐kV‐class GIS. The dielectric strengths of air and N2 gas are approximately one‐third that of SF6 gas. To enhance the insulation performance of air and N2 we have investigated a hybrid gas insulation system which has the combined features of providing an insulation coating and suitable insulation gas. We have developed the world's first 72‐kV SF6‐free GIS. This paper deals with key technologies for SF6‐free GIS, such as the hybrid insulation structure, a bellows for the high‐pressure vacuum circuit breaker, a newly designed disconnector and spacer, and prevention of particle levitation. Test results of the 72‐kV high‐pressure air‐insulated GIS with the vacuum circuit breaker are described. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(4): 13–23, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20451  相似文献   
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PURPOSE: We investigated the possible use of acupuncture for the treatment of urinary incontinence caused by detrusor hyperflexia in patients with chronic spinal cord injury. METHOD: A total of 8 male chronic spinal cord injured patients with urinary incontinence were treated by acupuncture. Their ages ranged from 20 to 33 years (mean 27). The level of lesion was cervical in 4 and thoracic in 4. Detrusor hyperreflexia with uninhibited bladder contraction was confirmed by urodynamic studies in all of them. Acupuncture was performed using a disposable stainless needle (0.3 mm in diameter, 60 mm in length), which was inserted into bilateral BL-33 (Zhongliao) points and was rotated manually for 10 minutes. The treatment was conducted every week for 4 weeks. Urodynamic studies were repeated, immediately after the beginning of and a week after the completion of the treatment. Urinary symptoms were also checked before and after the treatment. RESULTS: No side effects were recognized throughout the treatment period. Among 8 patients, incontinence was controlled completely in 3 (38%) and partially in 3 (38%). The average maximum cystometric bladder capacity increased significantly, from 42.3 +/- 37.9 ml to 148.1 +/- 101.2 ml by the treatment (p < 0.05), while the average maximum bladder pressure was not changed. CONCLUSIONS: These data suggest that acupuncture could be a promising alternative for conventional therapies for urinary incontinence caused by detrusor hyperreflexia in patients with chronic spinal cord injuries.  相似文献   
53.
New device isolation process, called elevated field insulator (ELFIN) process, for ultrathin SOI devices with top silicon film less than 20 nm has been proposed and successfully demonstrated. In ELFIN process, gate oxidation and subsequent gate poly-Si deposition is followed by conventional STI process. ELFIN process has a field region elevated compared with active silicon region, leading to prevention of silicon edge from being wrapped around by gate poly-Si. It is found that thin-film SOI NMOSFETs with ELFIN process have better reverse narrow channel effect about 50% at W/sub G/=0.3 /spl mu/m than that with conventional shallow trench isolation (STI) process.  相似文献   
54.
Cardiac function was assessed in long-term survivors of malignant bone tumors who were treated according to Rosen's T5 or T10 protocol, both including doxorubicin. Thirty-one patients, age 10-45 years (median age 17.8 years) were evaluated 2.3-14.1 years (median 8.9 years) following completion of treatment. Cumulative doses of doxorubicin were 225-550 mg/m2 (median dose 360). The evaluation consisted of a history, physical examination, electrocardiogram (ECG), signal averaged ECG, 24-hour ambulatory ECG, echocardiography and radionuclide angiography. Eighteen of 31 (58%) patients showed cardiac toxicity, defined as having one or more of the following abnormalities: late potentials, complex ventricular arrhythmias, left ventricular dilation, decreased shortening fraction, or decreased ejection fraction. The incidence of cardiac abnormalities increased with length of follow-up (P< or = .05). No correlation could be demonstrated between cumulative dose of doxorubicin and cardiac status, except for heart rate variability. When adjusted to body surface area, the left ventricular posterior wall thickness (LVPW index) was decreased in all patients. The incidence of doxorubicin-induced cardiotoxicity is high and increases with follow-up, irrespective of cumulative dose. Life-long cardiac follow-up in these patients is warranted. The results of our study suggest that heart rate variability and LVPW index could be sensitive indicators for cardiotoxicity.  相似文献   
55.
InGaAlAs-InAlAs electroabsorption modulators are successfully fabricated using ruthenium (Ru)-doped semi-insulating (SI)-InP burying technology. A comparison of measured and calculated microwave characteristics reveals that there is no additional microwave loss because zinc diffusion is inhibited by the use of Ru-doped SI-InP layers. A small-signal electrooptical response with a -3-dB electrical bandwidth of over 50 GHz is demonstrated.  相似文献   
56.
This paper proposes a new method for image template matching that is based on the correlation between edge‐spins. The edge‐spin is defined by the direction of the change of edge directions between neighboring pixels. When an edge direction rotates to the left from an objective pixel to its right neighboring pixel, the edge‐spin has the value 1. When an edge direction rotates to the right, the edge‐spin has the value 0. The edge‐spin is a binary data that represents the rotation of the edge direction. The edge‐spin is supposed to be robust to the change of brightness because the edge direction is not influenced by the linear change of brightness. The experimental results show that the proposed method has the superior reliability for the matching about most inferior experimental conditions in comparison with the conventional image template matching methods. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 153(2): 45–51, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20184  相似文献   
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A 1.5 ?m InGaAsP buried-heterostructure laser amplifier having small optical-mode confinement was fabricated with a Fabry-Perot cavity configuration. Its signal gain, saturation output power and noise characteristics were studied and found to be superior to those for AlGaAs amplifiers, as a result of small optical-mode confinement.  相似文献   
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