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1.
Images stored in resist for soft X-ray lithography or microradiography were found to show a background noise which limits the resolution. This is due to the statistically variable spatial distribution of the photons incident on the resist surface. An estimate of the fundamental noise-limited resolution has been made from the experimental measurement of photon flux incident on the surface and the accurate development rate curves. Monochromatic radiation from a synchrotron source was used.  相似文献   
2.
A second-generation model of cubicletype gas-insulated switchgear (C-GIS) with composite insulation incorporating SF6 gas has been developed. The design does not require a gas process in field assembly; it has high reliability and its installation is more rapid; and a further reduction in size is achieved. The design principles are described in detail.  相似文献   
3.
The exponential expansion of the Internet and the widespread popularity of the World Wide Web give a challenge to experts on reliable and secure system design, e.g., e-economy applications. New paradigms are on demand and mobile agent technology is one of the features. In this paper, we propose a fault-tolerance execution model by using of mobile agents, for the purpose of consistent and correct performance with a required function under stated conditions for a specified period of time. Failures are classified into two classes based on their intrinsic different effects on mobile agents. For each kind of failure, a specified handling method is adopted. The introduction of exceptional handling method allows performance improvements during mobile agents’ execution. The behaviors of mobile agents are statistically analyzed through several key parameters, including the migration time from node to node, the life expectancy of mobile agents, and the population distribution of mobile agents, to evaluate the performance of our model. The analytical results give new theoretical insights to the fault-tolerant execution of mobile agents and show that our model outperforms the existing fault-tolerant models. Our model provides an effective way to improve the reliability of computer systems.  相似文献   
4.
In evaluating the uncertainty of the standard measuring system for lightning‐impulse high voltages, which is composed of a standard voltage divider, a digital recorder, and calibrators, step‐response tests of the standard voltage divider may be useful. In this paper, a convolution algorithm is employed to calculate the output impulse voltage waveforms from measured step‐response waveforms. The uncertainties of peak‐value measurement due to the influence of the nominal epoch, uncertainty of the peak‐value measurement due to dispersion of the AC scale factor, and uncertainty of the virtual front‐time measurement due to long‐term stability are evaluated. Furthermore, the error of the virtual front time of the output waveforms is discussed. The front part of the step‐response waveform, tT30%, does not influence the error of the virtual front time. Therefore, for the standard voltage divider, the step‐response parameters, that is, the experimental response time, partial response time, settling time, and overshoot, have almost nothing to do with the error of the virtual front time. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 180(2): 24–32, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21279  相似文献   
5.
Solid oxide fuel cells (SOFCs) are being researched around the world. In Japan, a compact SOFC system with rated alternative current (AC) power of 700 W has become available on the market, since the base load electricity demand for a standard home is said to be less than 700 W AC. To improve the generating efficiency of SOFC systems in the 700-W class, we focused on thermoelectric generation (TEG) technology, since there are a lot of temperature gradients in the system. Analysis based on simulations indicated the possibility of introducing thermoelectric generation at the air preheater, steam generator, and exhaust outlet. Among these options, incorporating a TEG heat exchanger comprising multiple CoSb3/SiGe-based TEG modules into the air preheater had potential to produce additional output of 37.5 W and an improvement in generating efficiency from 46% to 48.5%. Furthermore, by introducing thermoelectric generation at the other two locations, an increase in maximum output of more than 50 W and generating efficiency of 50% can be anticipated.  相似文献   
6.
We examined by light and electron microscopy the immature skeletal muscle fibers in the rat sciatic nerve regenerating within the silicone chamber 14 days after nerve transection. Small myelinated and nonmyelinated nerve fibers associated with Schwann cells from the proximal stump began to approach the midportion of the interstump zone. In the middle segment, fibroblasts or fibroblast-like mesenchymal cells and macrophages were observed everywhere in the newly formed matrix filled with exuded erythrocytes and fibrin clots. In addition to some fibroblast-like mesenchymal cells were closely apposed to each other. However, the proximal and distal segments contained immature muscle fibers with various amount of myofilaments and one or plural centrally located nuclei, thus indicating various phases of the early differentiation of skeletal muscle fibers similar to those observed during an early stage of developing muscle fibers. However, the precise origin of these skeletal muscle fibers remains to be determined.  相似文献   
7.
This paper proposes novel grounded and floating high order series and parallel immittance simulators using operational transconductance amplifiers (OTAs) and operational amplifiers (OAs) with a finite gain–bandwidth (GB) product. They are composed of active devices (OTAs and OAs) and resistances, and are suitable for monolithic implementation in either CMOS or bipolar technologies. They also realize both positive and negative high order immittances. The circuit characteristics can be electronically tuned by adjusting the transconductances of OTAs and the GB products of OAs. Any transfer functions are realizable using the proposed simulators. Two examples are shown, together with simulation results.  相似文献   
8.
9.
Based on a calculation for the Raman gain coefficient of the S0(2) transition in ortho-D2, we have demonstrated the generation of first Stokes waves in the 15-16-μm spectral region. Use of ortho-D enriched by a catalytic converter enabled us to realize efficient conversion at room temperature. Stokes energies as high as 400 mJ were obtained  相似文献   
10.
Certain strains of lactic acid bacteria present in commercial cheese starters, characterized by faint transparent colonies on an agar plate containing 1 mg kg −1 crystal violet (CVT), were identified as Lactococcus lactis subsp. (ssp) lactis biovar diacetylactis. The effect of citrate on the growth of these strains (CVT strains) in the presence of glucose was studied, in comparison with L. lactis strains. Molar growth yield from glucose (YG, g dry weight/mole of glucose consumed) for CVT strains grown on glucose plus citrate was significantly higher than the control (i.e. without citrate), but not for other L. lactis strains tested. Enhanced YG was also observed at a pH-controlled experiment, indicating that enhanced YG did not result from a buffering effect of citrate. CVT strains, in contrast to other strains of the same species, were shown to obtain enough energy to enhance YG on glucose–citrate mixtures.  相似文献   
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