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81.
Mohri A. Yamada A. Yoshida Y. Sato H. Takata H. Nakakimura K. Hashizume M. Shimotsuma Y. Tsuchihashi K. 《Solid-State Circuits, IEEE Journal of》1999,34(7):992-1000
A real-time system large-scale-integrated circuit (LSI) for digital video cassette recorder (DVCR) encoding/decoding and MPEG-2 decoding is implemented on a dual-issue RISC processor (DRISC) with dedicated hardware optimized for video-block processing. The DRISC achieves 972-MOPS software performance and can execute fixed-length data processing at the block level as well as processing at the macro-block level and above for the DVCR/MPEG-2. The dedicated hardware for variable-length coding/decoding can encode and decode codes for both the DVCR and the MPEG-2 by changing translation tables. The dedicated hardware for video-block loading can process video-block data transfers with half-pel operations. The LSI size is 7.7×7.2 mm2 in a 0.25-μm CMOS process 相似文献
82.
Takakuni Douseki Takeshi Yamada Junzo Yamada Kazuyuki Ito Kazuo Nishi 《Solar Energy Materials & Solar Cells》2001,67(1-4)
We have developed a mobile global positioning system (GPS) that operates on just photovoltaic (PV) cells. The system receives wireless signals from satellites and shows one's present location accurately on a map without the need for a battery. A PV display module, which combines a transparent LCD with a-Si PV cells and has a power generation function, is added to ordinary PV cells to increase the total amount of power generated. The PV display module enables 40% more power generation than a system without the module. 相似文献
83.
Abrupt changes in the cross-polarization discrimination (XPD) and cross-polar phase were observed in cross-polarization measurements at 4, 6, and 11 GHz on propagation paths with low elevation angles. These abrupt changes were always observed during thunder, though exact time-to-time correspondence with lightning strokes was not clear in the measurement. In most cases, these sudden changes occurred in the direction in which the distortion of polarization ellipse increases, and the rate of change in XPD was much faster than rain-induced depolarizations by an order of magnitude. Based on the simultaneous measurement of circular and linear polarizations at 11 GHz, it was also found that the differential phase shift component suddenly increased to as large as20deg to40deg upon occurrence of these XPD changes, which confirms that this phenomenon is attributed to the effect of ice particles. 相似文献
84.
The s-shaped growth curves of detected software errors can be observed in software testing. The delayed s-shaped and inflection s-shaped software reliability growth models based on a nonhomogeneous Poisson process are discussed. The software reliability growth types of the models are investigated in terms of the error detection rate per error. In addition, a viable method for the software quality assessment, which integrates the capture-recapture method and the models above, is discussed, and its application to actual test data is illustrated. 相似文献
85.
Far-infra-red photoconductivity measurements are used to study residual shallow donor species in InP bulk crystals grown by the synthesis, solute-diffusion technique. The observation of 1s-2p, m =+ 1 Zeeman transitions between the shallow donor-impurity states reveals that two dominant residual donors are included in the InP bulk crystals having carrier concentrations of less than 1 × 1015 cm?3 The donors are tentatively identified as Si and S. 相似文献
86.
Shota Yamada Yucheng Shang Iori Yamada Motohiro Tagaya 《Advanced Powder Technology》2019,30(5):1116-1119
Phosphonate-containing mesoporous silica (PMPS) spheres were successfully synthesized using diethyl(2-bromoethyl)phosphonate and non-ionic and cationic surfactants. The spherical PMPS particles with the mesopores were effectively formed under the basic condition through the hydrolysis and condensation reactions of tetraethoxysilane, even though the BET surface area of the particles decreased with increasing the added phosphonate amount. The hollow structures with the mesopores were obtained in the preferential amount of the phosphonate. 相似文献
87.
An electrochromic (EC) switchable mirror glass can change between a reflective state and a transparent state with voltage application. The conventional device has a multilayer of Mg4Ni/Pd/Al/Ta2O5/WO3/indium-tin oxide on a transparent substrate. A palladium thin film was used as the proton injection layer. For practical use, we attempted to reduce the amount of palladium thin film from the viewpoints of the reduction in total fabrication cost and the efficient use of resources. The thickness of the film was related to the optical switching properties of the device. Although the device with a 1-nm-thick palladium film showed a high transmittance of 63% in the transparent state, its low switching durability was not suitable for practical application.Moreover, we were able to adapt a palladium-based alloy (Pd0.8Ag0.2) which is a well-known hydrogen permeation membrane as the proton injection layer to reduce the amount of palladium thin film. As a result, we found that a 4-nm-thick Pd-Ag thin film has good adaptability to the EC switchable mirror. 相似文献
88.
N. Sasajima D. Lowe C. Bai Y. Yamada C. Ara 《International Journal of Thermophysics》2011,32(11-12):2696-2707
The Cr3C2?C peritectic fixed point was investigated to test its capability to serve as a practical high-temperature fixed point. An improved filling technique where C/C sheet works as a wick and graphite paper as a hopper was applied successfully, and the long-term stability of the peritectic cell was evaluated by means of radiation thermometry. The repeatability of the melting point in one day was 7 mK with a melting range of approximately 100 mK. The cell was aged for 7 days, and the evaluated 56 melting temperatures during this period all fall within 90 mK, with a standard deviation of 19 mK. X-ray transmission photos showed that the ingot was filled uniformly in the crucible. After the evaluation of long-term stability, no clear degradation of the ingot shape and no leakage of molten metal were observed. From these results, it can be concluded that the Cr3C2?C peritectic cell has good stability and robustness, and the new filling technique was established. The impurity effect on the Cr3C2?C peritectic cell was also investigated by adding tungsten powder to another cell as the impurity component. After the observation of melting and freezing plateaux, the cell was cut in half to analyze the microstructure by means of electron probe microanalysis (EPMA) and laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS). The high concentration of impurity was observed in the area of the chromium-rich domain (eutectic mixture of Cr7C3 and Cr3C2), which suggests that impurities were rejected from the Cr3C2 peritectic phase during the peritectic freezing and were accumulated in the Cr7C3?Cr3C2 eutectic phase. This explains why the impurity effect is more severe for the Cr7C3?Cr3C2 eutectic point than for the Cr3C2?C peritectic point. 相似文献
89.
90.
Aortic aneurysms are sometimes associated with enhanced-fibrinolytic-type disseminated intravascular coagulation (DIC). In enhanced-fibrinolytic-type DIC, both coagulation and fibrinolysis are markedly activated. Typical cases show decreased platelet counts and fibrinogen levels, increased concentrations of fibrin/fibrinogen degradation products (FDP) and D-dimer, and increased FDP/D-dimer ratios. Thrombin-antithrombin complex or prothrombin fragment 1 + 2, as markers of coagulation activation, and plasmin-α2 plasmin inhibitor complex, a marker of fibrinolytic activation, are all markedly increased. Prolongation of prothrombin time (PT) is not so obvious, and the activated partial thromboplastin time (APTT) is rather shortened in some cases. As a result, DIC can be neither diagnosed nor excluded based on PT and APTT alone. Many of the factors involved in coagulation and fibrinolysis activation are serine proteases. Treatment of enhanced-fibrinolytic-type DIC requires consideration of how to control the function of these serine proteases. The cornerstone of DIC treatment is treatment of the underlying pathology. However, in some cases surgery is either not possible or exacerbates the DIC associated with aortic aneurysm. In such cases, pharmacotherapy becomes even more important. Unfractionated heparin, other heparins, synthetic protease inhibitors, recombinant thrombomodulin, and direct oral anticoagulants (DOACs) are agents that inhibit serine proteases, and all are effective against DIC. Inhibition of activated coagulation factors by anticoagulants is key to the treatment of DIC. Among them, DOACs can be taken orally and is useful for outpatient treatment. Combination therapy of heparin and nafamostat allows fine-adjustment of anticoagulant and antifibrinolytic effects. While warfarin is an anticoagulant, this agent is ineffective in the treatment of DIC because it inhibits the production of coagulation factors as substrates without inhibiting activated coagulation factors. In addition, monotherapy using tranexamic acid in cases of enhanced-fibrinolytic-type DIC may induce fatal thrombosis. If tranexamic acid is needed for DIC, combination with anticoagulant therapy is of critical importance. 相似文献