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排序方式: 共有1313条查询结果,搜索用时 15 毫秒
101.
Daikoku M. Morita I. Taga H. Tanaka H. Kawanishi T. Sakamoto T. Miyazaki T. Fujita T. 《Lightwave Technology, Journal of》2007,25(1):139-145
In order to realize a future 100-Gb Ethernet (100 GbE) transport, 100-Gb/s transmission without 100-GHz-class electronics and optical time-division-multiplexing technique was demonstrated. By using a differential quadrature phase-shift-keying (DQPSK) modulation format and commercially available electronics, 2- and 50-km transmissions of 100-Gb/s signal were successfully achieved over a standard single mode fiber. The receiver sensitivity, chromatic dispersion, and differential group delay tolerances of 100-Gb/s DQPSK signal were also evaluated. Through these evaluations, the possibility of DQPSK modulation for future 100-GbE transport is verified 相似文献
102.
Wavelength-tunable ultra-flat optical frequency comb generation is demonstrated using only a conventional Mach-Zehnder modulator that is asymmetrically dual-driven by large-amplitude sinusoidal signals with different amplitudes. A 10 GHz-spaced frequency comb with a 10 dB bandwidth of 230 GHz was experimentally generated. In addition, 50 nm widely wavelength tunable operation was achieved. 相似文献
103.
Naonori Sakamoto Shunji Araki Masahiro Yoshimura 《Journal of the American Ceramic Society》2009,92(S1):S157-S161
Eutectic melt solidification is shown to avoid cracking during solidification by quenching an amorphous phase. Subsequent annealing results in micro/nanostructure ceramics. This strategy has been applied to HfO2 –Al2 O3 –GdAlO3 and Y2 O3 –CaO–Al2 O3 ternary systems that have deep eutectics. In most cases, ceramic materials cracks when they are solidified from melt due to the thermal stress accumulated on the grain boundaries, the large specific volume difference between the melt and the crystalline solid, etc. The main reason why this strategy works is that a eutectic composition yields an amorphous phase from the melts by rapid cooling and the amorphous phase enables to design crystallization without cracking by postannealing. Appropriate postannealing for the quenched amorphous enables to control the crystallization behavior from the amorphous phase, which yields nanostructured composites without cracking. For the HfO2 –Al2 O3 –GdAlO3 case, the melt solidification and postannealing yields a nanocomposite with high transparency due to reduced scattering of 5–10 nm crystallites. For the Y2 O3 –CaO–Al2 O3 case, a plate-shaped bulk composite is obtained without cracking by molding the melt and postannealing. 相似文献
104.
Sakamoto M. Cardinal M.R. Endriz J.G. Welch D.F. Scifres D.R. 《Electronics letters》1990,26(7):422-424
One cm wide monolithic laser diode arrays emitting around 810 nm with a 2 mm total aperture width have been characterised under CW conditions. CW operation up to 16 W has been achieved at a heatsink temperature of 70 degrees C. Several arrays have been lifetested at 10 W CW at a 20 degrees C heatsink temperature for a few thousand hours and have projected lifetimes of between 5000 and 17000 hours. The temperature dependence of the degradation rate was characterised, from which data an activation energy of 0.2 eV was obtained.<> 相似文献
105.
Satoshi Miyaguchi Shinichi Ishizuka Takeo Wakimoto Jun Funaki Yoshinori Fukuda Hirofumi Kubota Kenji Yoshida Teruichi Watanabe Hideo Ochi Tsuyoshi Sakamoto Masami Tsuchida Isamu Ohshita Teruo Tohma 《Journal of the Society for Information Display》1999,7(3):221-226
Abstract— A full-color 5.2-inch 1/4-VGA passive-matrix organic LED display has been developed, adopting selective deposition for the different emitting materials. The display features 320 (×3) × 240 pixels with an equivalent pixel size of 0.33 × 0.33 mm, white peak luminance of over 150 cd/m2, and power consumption of 6 W. 相似文献
106.
Hemophilia B is caused by a deficit or decreased activity of factor IX. Mutation in factor IX is made up of a majority of
amino acid substitutions. We examined the relation between the activation level of factor IX and the category of amino acid
substitution with regression analysis. As parameters, we used four physical-chemical parameters of amino acids and Dayhoff’s
PAM matrix. In addition, the average of the activation level with the same amino acid substitution was used for the analysis.
We analyzed the relationship between variations containing cysteine or factor IX’s seven regions and activity levels.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
107.
108.
109.
Masakazu Ejiri Haruo Yoda Hiroshi Sakou Yuzaburo Sakamoto 《Machine Vision and Applications》1989,2(3):155-166
Combining the knowledge-based processing with image processing is considered a key issue in the future of visual inspection of complex patterns such as multilayered semiconductor wafers. However, present technology restricts this combination, mainly because of the exhaustively long time usually required for each type of processing. To cope with this situation, a unique knowledge-directed image processing method is proposed, in which every image processing step is controlled in real time by parametric knowledge driven by design patterns. The resulting structure of the image processor is a pipeline, in which each piece of knowledge is embodied as a combination of a hardware processing unit and control unit. In this paper the types of knowledge and their implementation are explained, and an inspection machine for logic IC wafers based on this pipelined knowledgedirected image processing is introduced. 相似文献
110.
Shigemitsu Hatanaka Eisuke Sakamoto Naoki Mishima Akio Muramatsu 《Materials and Structures》2008,41(7):1235-1249
The strength and hardness of concrete slab surface is considered significantly affected by bleeding of concrete. It has been
reported that dewatering by vacuum processing is quite effective to obtain high density of concrete. The method, however,
has not been successfully used for the concrete work in the field of building construction, compared with that of civil engineering
works in Japan. In the present study, firstly the state of the art concerning vacuum dewatering method is reviewed and the
newly improved vacuum dewatering method is introduced. Then the effect of the proposed method on concrete properties of slab
is examined by a series of experiments in order to find more reasonable and effective way in the application of the proposed
method. 相似文献