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排序方式: 共有3546条查询结果,搜索用时 15 毫秒
101.
Yuichiro Ezoe Ikuyuki Mitsuishi Utako Takagi Masaki Koshiishi Kazuhisa Mitsuda Noriko Y. Yamasaki Takaya Ohashi Fumiki Kato Susumu Sugiyama Raul E. Riveros Hitomi Yamaguchi Shinya Fujihira Yoshiaki Kanamori Kohei Morishita Kazuo Nakajima Ryutaro Maeda 《Microsystem Technologies》2010,16(8-9):1633-1641
We are developing novel ultra light-weight and high-resolution X-ray micro pore optics for space X-ray telescopes. In our method, curvilinear micro pore structures are firstly fabricated by silicon deep reactive ion etching (DRIE) or X-ray LIGA processes. Secondly, side walls of the micro structures are smoothed by magnetic field assisted finishing and/or hydrogen annealing techniques for high reflectivity mirrors. Thirdly, to focus parallel X-ray lights from astronomical objects, these structures are elastically or plastically bent into a spherical shape. Fourthly, the bent structures are stacked to form a multi-stage X-ray telescope. In this paper, we report on fabrication and X-ray reflection tests of silicon and nickel X-ray mirrors using the DRIE and LIGA processes, respectively. For the first time, X-ray reflections were confirmed on both of the mirrors. Estimated rms roughnesses were 5 nm and 3 nm for the silicon and nickel mirrors, respectively. 相似文献
102.
Prediction of Human Behavior in Human--Robot Interaction Using Psychological Scales for Anxiety and Negative Attitudes Toward Robots 总被引:2,自引:0,他引:2
When people interact with communication robots in daily life, their attitudes and emotions toward the robots affect their behavior. From the perspective of robotics design, we need to investigate the influences of these attitudes and emotions on human-robot interaction. This paper reports our empirical study on the relationships between people's attitudes and emotions, and their behavior toward a robot. In particular, we focused on negative attitudes, anxiety, and communication avoidance behavior, which have important implications for robotics design. For this purpose, we used two psychological scales that we had developed: negative attitudes toward robots scale (NARS) and robot anxiety scale (RAS). In the experiment, subjects and a humanoid robot are engaged in simple interactions including scenes of meeting, greeting, self-disclosure, and physical contact. Experimental results indicated that there is a relationship between negative attitudes and emotions, and communication avoidance behavior. A gender effect was also suggested. 相似文献
103.
Yamamoto T Kato R Yamamoto HM Fukaya A Yamasawa K Takahashi I Akutsu H Akutsu-Sato A Day P 《The Review of scientific instruments》2007,78(8):083906
We have developed a technique for the anisotropic extension of fragile molecular crystals. The pressure medium and the instrument, which extends the pressure medium, are both made from epoxy resin. Since the thermal contraction of our instrument is identical to that of the pressure medium, the strain applied to the pressure medium has no temperature dependence down to 2 K. Therefore, the degree of extension applied to the single crystal at low temperatures is uniquely determined from the degree of extension in the pressure medium and thermal contractions of the epoxy resin and the single crystal at ambient pressure. Using this novel instrument, we have measured the temperature dependence of the electrical resistance of metallic, superconducting, and insulating materials. The experimental results are discussed from the viewpoint of the extension (compression) of the lattice constants along the parallel (perpendicular) direction. 相似文献
104.
A regenerative tin liquid microjet target was developed for a high average power extreme ultraviolet (EUV) source. The diameter of the target was smaller than 160 microm and good vacuum lower than 0.5 Pa was maintained during the operation. A maximum EUV conversion efficiency of 1.8% at the Nd:yttrium-aluminum-garnet laser intensity of around 2 x 10(11) Wcm(2) with a spot diameter of 175 microm (full width at half maximum) was observed. The angular distribution of the EUV emission remained almost isotropic, whereas suprathermal ions mainly emerged toward the target normal. 相似文献
105.
I Tanabe K Kusaba Z Nagasawa Y Tajima J Tadano N Fujisawa O Kato H Yamada 《Canadian Metallurgical Quarterly》1993,67(8):718-723
A recent nationwide increase in beta-lactams-resistant Streptococcus pneumoniae has attracted a great deal of attention. We studied the drug sensitivity of S. pneumoniae isolated from various clinical specimens in Saga Medical School Hospital between April 1988 and December 1991. To determine the drug sensitivity of the strains, we used a micro-dilution method and determined the MIC. Drug resistance was evaluated using MIC of ampicillin (ABPC) as a reference MIC, and the results were roughly classified into the following three groups: sensitive (< or = 0.1 microgram/ml), moderately resistant (0.2-3.13 micrograms/ml) and highly resistant (> or = 6.25 micrograms/ml). The isolation frequency was calculated on the basis of one strain from one patient. No strain of S. pneumoniae with high resistance against ABPC was found in 1988 (94 strains of S. pneumoniae were isolated) and 1990 (115 strains isolated), but one such strain (0.8%) was found among 129 strains isolated in 1989, and 2 such strains (2.4%) among 84 strains isolated in 1991. Moderately resistant strains were isolated at the frequencies of 12.8%, 15.5%, 22.6%, and 21.4% respectively, in 1988, 1989, 1990, and 1991. A sum of the frequencies of "moderately resistant" and "highly resistant" (2.4%) strains was 23.8% in 1991. The frequency of resistant strains is increasing and the intensity of resistance is also being elevated. 相似文献
106.
107.
108.
H. Sawa Y. Wakabayashi R. Tazaki T. Kakiuchi K. Kanoda R. Kato 《Journal of Low Temperature Physics》2006,142(3-4):355-360
Synchrotron X-ray high-resolution measurements have been performed to investigate the nature of the insulating state of a
quarter-filled quasi-one-dimensional conductor (DI-DCNQI)2Ag and the π-d interacted conductor (DBr-DCNQI)2Cu. The two-fold structure in the ground state of (DI-DCNQI)2Ag system consists of not only charge ordering columns but also monotonic charge dimerized columns caused by frustration among
DCNQI columns. On the other hand, Cu salt in the insulating phase realizes a commensurate structure where the Cu charge ordering
is coupled with the 3c-CDW in the insulator phase. The frustration among charged columns is restrained by the charge ordering
of the Cu ions. 相似文献
109.
Kato K. Kurimoto M. Shumiya H. Adachi H. Sakuma S. Okubo H. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2006,13(2):362-372
Functionally graded materials (FGM) have spatial distribution of a material property in order to achieve efficient stress control. An application of the FGM to a solid insulator (spacer) for a gaseous insulation system, like gas insulated switchgear, is expected to improve electric field (E-field) distribution around the spacer. In this paper, we describe the applicability of the FGM spacer to gas insulated power equipment. In the FGM spacer, we gave spatial distribution of dielectric permittivity to control the E-field distribution inside and outside the spacer. This paper includes following key results for the applications of the FGM. Firstly, E-field simulation results when applying the FGM by a finite element method are presented, in which we show the effective reduction of the maximum field strength by applying the FGM. Next, a fabrication technique of the FGM spacer sample with not only step-by-step but also continuous changes of permittivity is presented by use of centrifugal force. Finally, dielectric breakdown tests using FGM samples which are accurately controlled the spatial distribution of permittivity are carried out under lightning impulse voltage applications. The test result indicates the increase of breakdown voltage (BDV). From these results, we verified the applicability and the fabrication technique of FGM spacer for improvement of the dielectric strength in the gaseous insulation system. 相似文献
110.
The constant-ratio-coupled multi-grain digital synchronizer (CRC-MGsynchronizer) is proposed as a means for making high-speed connections with very low power consumption, both among multiple chips such as processors, controllers, and storage devices, and among on-chip modules. The synchronizer not only provides a wide range of operating frequencies, but is fast locking and only occupies a small area on chip. Therefore, it contributes to large reductions in power consumption and costs. It is suitable for use in various low-power systems (e.g., battery-hungry mobile appliances and low-cost consumer electronic products). Three major techniques were applied to the design: 1)a multi-grain structure for the delay elements, which greatly reduces the number of gates while facilitating locking in a very small number of clock cycles;2) constant-ratio-coupled (CRC) delay lines (measurement versus generation)for flexible selection of the input-output delay; and 3) a new lock stage decision circuit (LSDC) scheme, conferring excellent testability. Moreover,the architecture is all-digital, and thus it has high process portability. By applying these techniques to a DDR memory interface circuit for a mobile application processor fabricated in 130-nm technology, we were able to reduce power consumption by 42% and chip area by 65% compared with a conventional implementation. Furthermore, the novel design spans a frequency range covering 12 times the minimum frequency. 相似文献