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排序方式: 共有866条查询结果,搜索用时 31 毫秒
1.
Annals of Mathematics and Artificial Intelligence - The inner representation of deep neural networks (DNNs) is indecipherable, which makes it difficult to tune DNN models, control their training... 相似文献
2.
Electrical Breakdown Properties and Space Charge Formation in High Temperature Region in Ultraviolet Ray Irradiated PVC 下载免费PDF全文
Polyvinyl chloride (PVC) is the most popular insulating material for electric wiring instruments. However, an exothermic reaction above 150 °C may cause deterioration of the insulating properties of PVC. Therefore, it is important to clarify the heat degradation in PVC, not only to investigate the ignition of electrical wiring products but also to use electrical products safely. It is known that ultraviolet (UV) irradiation causes chemical deterioration of PVC and an increase in its conductivity. Generally, it has been thought that the electrical breakdown properties, electrical conduction, and insulating performance are affected by space charge accumulation in an insulating material. A high temperature pulsed electroacoustic (PEA) system usable up to 250 °C has been developed, and the PEA system can measure the space charge distribution and conduction current in the high temperature range simultaneously. In this investigation, the space charge distribution and conduction current were measured up to electrical breakdown in a non‐UV irradiated sample (normal PVC) and in 353 nm and 253 nm UV‐irradiated PVC samples in the range from room temperature to 200 °C in a DC electric field. In the short wavelength UV irradiated PVC sample (253 nm, 300 h), a deterioration of breakdown strength at 90 °C to 150 °C and negative packet‐like charges were observed at 60 °C and 100 °C, a positive charge accumulated in front of both the anode and cathode above 90 °C, and a higher electric field near the cathode side because the positive charge of the cathode side was greater. 相似文献
3.
Iwao Shimizu Yuji Naito Iwao Yamaguchi Katsuyuki Kaiho Hitoshi Mizoguchi Satoru Yanabu 《Electrical Engineering in Japan》2008,164(1):52-61
Using conventional high‐temperature superconducting wire, a model superconducting fault current limiter (SFCL) is made and tested. Solenoid coil using Bi2223 silver sheath wire is so made that inductance is as small as possible and a vacuum interrupter is connected in series to it. A conventional reactor coil is connected in parallel. When the fault current flows in this equipment, superconducting wire is quenched and current is transferred into the parallel coil because of voltage drop of superconducting wire. This large current in parallel coil actuates magnetic repulsion mechanism of vacuum interrupter. Due to opening of vacuum interrupter, the current in superconducting wire is broken. By using this equipment, current flow time in superconducting wire can be easily minimized. On the other hand, the fault current is also easily limited by large reactance of parallel coil. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 164(1): 52–61, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20315 相似文献
4.
Several types of reinforced Nb3Sn wires have been developed to prevent reduction of superconducting properties by applying a strong electromagnetic force. To fabricate a cryocooled magnet using those reinforced wires, we experimentally measured the minimum quench energy (MQE) under cryocooled conditions of some reinforced Nb3Sn wires. As a result, it became clear that thermal stability expressed as MQE was controlled by the temperature margin between the temperature of the operating condition and the transition temperature from superconductivity to normal. Using the FEM analysis, it was realized that the cause of the decline in thermal stability for the reinforced wires was the low thermal conductivity of the reinforced materials. 相似文献
5.
Saito M. Yoshitomi T. Hara H. Ono M. Akasaka Y. Nii H. Matsuda S. Momose H.S. Katsumata Y. Ushiku Y. Iwai H. 《Electron Devices, IEEE Transactions on》1993,40(12):2264-2272
A p-MOSFET structure with solid-phase diffused drain (SPDD) is proposed for future 0.1-μm and sub-0.1-μm devices. Highly doped ultrashallow p+ source and drain junctions have been obtained by solid-phase diffusion from a highly doped borosilicate glass (BSG) sidewall. The resulting shallow, high-concentration drain profile significantly improves short channel effects without increasing parasitic resistance. At the same time, an in situ highly-boron-doped LPCVD polysilicon gate is introduced to prevent the transconductance degradation which arises in ultrasmall p-MOSFETs with lower process temperature as a result of depletion formation in the p+-polysilicon gate. Excellent electrical characteristics and good hot-carrier reliability are achieved 相似文献
6.
7.
Satoru INOUE Kauuhide EGUCHI Tsunehiko IMAMOTO Mitsunori KlSHI 《Drying Technology》1992,10(3):679-714
In coating and gravure printing, an impinging jet nozzle with high thermal efficiency for drying of coated film was developed.
Trial production 0f 40 kinds of nozzle enables to develop a high-performance impinging jet nozzle with heat transfer coefficient 1.5 times larger than that of current slit nozzle, through measurement of heat transfer coefficient, visualizations of air flow and heat transfer, and measuremenu of jet velocity and turbulence distribution. The purpose of the trial production was to expand a range of high heat transfer and promote turbulence compared with the current nozzle.
Paying attention to mass transfer within gravure ink coated film, drying characteristic of the film was analyzed by numerical solution of a set of equations governing the drying process in which concentration dependencies 0f the diffusion coefficient and the equilibrium vapor pressure were considered.
Applying these analyses. an industrial scale dryer with excellent drying efficiency has finally been developed. 相似文献
Trial production 0f 40 kinds of nozzle enables to develop a high-performance impinging jet nozzle with heat transfer coefficient 1.5 times larger than that of current slit nozzle, through measurement of heat transfer coefficient, visualizations of air flow and heat transfer, and measuremenu of jet velocity and turbulence distribution. The purpose of the trial production was to expand a range of high heat transfer and promote turbulence compared with the current nozzle.
Paying attention to mass transfer within gravure ink coated film, drying characteristic of the film was analyzed by numerical solution of a set of equations governing the drying process in which concentration dependencies 0f the diffusion coefficient and the equilibrium vapor pressure were considered.
Applying these analyses. an industrial scale dryer with excellent drying efficiency has finally been developed. 相似文献
8.
Yamaoka M. Maeda N. Shinozaki Y. Shimazaki Y. Nii K. Shimada S. Yanagisawa K. Kawahara T. 《Solid-State Circuits, IEEE Journal of》2006,41(3):705-711
The power consumption of a low-power system-on-a-chip (SoC) has a large impact on the battery life of mobile appliances. General SoCs have large on-chip SRAMs, which consume a large proportion of the whole LSI power. To achieve a low-power SoC, we have developed embedded SRAM modules, which use some low-power SRAM techniques. One technique involves expanding the write margin; another is a power-line-floating write technique, which enables low-voltage write operation. The power-line-floating write technique makes it possible to lower the minimum operating supply voltage by 100 mV. The other techniques involve using a process-variation-adaptive write replica circuit and reducing leakage current. These techniques reduce active power during write operations by 18% and reduce active leakage of the word-line driver by 64%. The prototype SRAM modules achieve 0.8-V operation, and a 512-kb SRAM module achieves 48.4-/spl mu/A active leakage and 7.8-/spl mu/A standby leakage with worst-leakage devices. 相似文献
9.
Starting from an effective action for the order parameter field, we derive a coupled set of generalized hydrodynamic equations
for a Bose condensate in an optical lattice at finite temperatures. Using the linearized hydrodynamic equations, we study
the microscopic mechanism of the Landau instability due to the collisional damping process between the condensate and noncondensate
atoms. It is shown that the Landau criterion for the stability of a superfluid in a uniform system is modified due to the
presence of the periodic optical lattice potential. 相似文献
10.
We developed a noble technique for the fine-particle handling in plasmas. In this method a pair of point electrodes are introduced in the plasma, to which positive pulses are applied alternatively. When the pulse repetition period is shorter than the particle response time, the particles feel only time-averaged force because of their large mass. Spatial profile of the equivalent potential of the time-averaged force varies from a circle to an ellipse with an increase in the local discharge at the electrodes. The particles are eventually transported toward a middle point between two point-electrodes, being almost independent of their initial positions. This method is quite effective for converging fine particles in the plasma. 相似文献