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71.
Due to the recent popularization of mobile multimedia broadcasting, broadcasting continuous media data such as audio and video has attracted great deal of attention. In general continuous media data broadcasting, since clients have to wait to receive data before playing it, various schemes to reduce waiting time have been studied. Some reduce the waiting time by dividing the data into several segments and broadcasting preceding segments frequently with a single channel. However, by dividing the data into numerous segments and producing an effective broadcast schedule, the waiting time can be further reduced. In this paper, we propose a scheduling protocol to reduce waiting time with large-scale data segmentation. 相似文献
72.
Ishikura S. Kurumada M. Terano T. Yamagami Y. Kotani N. Satomi K. Nii K. Yabuuchi M. Tsukamoto Y. Ohbayashi S. Oashi T. Makino H. Shinohara H. Akamatsu H. 《Solid-State Circuits, IEEE Journal of》2008,43(4):938-945
We propose a new 2-port SRAM with a single read bit line (SRBL) eight transistors (8 T) memory cell for a 45 nm system-on-a-chip (SoC). Access time tends to be slower as a fabrication is scaled down because of threshold voltage (Vt) random variations. A divided read bit line scheme with shared local amplifier (DBSA) realizes fast access time without increasing area penalty. We also show an additional important issue of a simultaneous read and write (R/W) access at the same row by using DBSA with the SRBL-8T cell. A rise of the storage node causes misreading. A read end detecting replica circuit (RER) and a local read bit line dummy capacitance (LDC) are introduced to solve this issue. A 128 bit lines - 512 word lines 64 kb 2-port SRAM macro using these schemes was fabricated by a 45 nm bulk CMOS low-standby-power (LSTP) CMOS process technology [1]. The memory cell size is 0.597 mum2. This 2-port SRAM macro achieves 7 times faster access time without misreading. 相似文献
73.
Tajima T Sakata W Wada T Tsutsui A Nishimoto S Miyake M Takaguchi Y 《Advanced materials (Deerfield Beach, Fla.)》2011,23(48):5750-5754
A coaxial nanohybrid consisting of a single-walled carbon nanotube (SWCNT), fullerodendron, and SiO(2) shows high-efficiency light-driven hydrogen evolution from water. Upon visible light irradiation, SWCNT/fullerodendron/SiO(2) coaxial nanohybrid shows hydrogen evolution activity in the presence of methyl viologen (MV(2+)), benzyldihydronicotinamide (BNAH), and a colloidal polyvinyl alcohol(PVA)-Pt. 相似文献
74.
Dynamic deformation measurement with a large deformation is effectively performed by using virtual speckle patterns. The virtual
speckle pattern has been generally produced by using the operation based on Fourier transform. However, it takes a long calculating
time to produce a virtual speckle pattern, because the method requires Fourier transform operation at each pixel of CCD. In
the proposed method, virtual speckle patterns are produced by Carré algorithm without any operation by Fourier transform.
The method is applied to the in-plane deformation measurement in this paper. As the results, it is confirmed that the calculating
cost of virtual speckle patterns is improved remarkably, and that the measurement accuracy of the new method is also equal
to the ordinary methods. It is also confirmed that the proposed method will expand the use of the speckle interferometry based
on virtual speckle pattern technology. 相似文献
75.
76.
T Shuto K Hirohashi S Kubo H Tanaka T Tsukamoto T Yamamoto T Ikebe H Kinoshita 《Canadian Metallurgical Quarterly》1998,28(11):1124-1129
In an attempt to define better surgical strategies for patients with hepatocellular carcinoma (HCC), we conducted a retrospective analysis of 452 patients who underwent hepatic resection at our institute during a period of 15 years. The patients were divided into two groups: group A, comprising 188 patients who underwent hepatic resection before 1988, and group B, comprising 264 patients after 1989. These groups were compared clinicopathologically. The percentage of patients with Child's A disease but without cirrhosis, in group A was lower. The diameter of the resected tumor was larger in group A, and major hepatic resections and curative operations were more frequently performed in group A. In group B, there was less blood loss, the specimen weighed less, and the hospital mortality was lower. Although the tumor-free survival rates were similar between the two groups, the survival rate in group B was significantly better. While even minor hepatic resection accompanied by a lower rate of surgical margin-free surgery has contributed to making hepatic resection safer, it has not improved the tumor-free survival rate. Conversely, recent advances in imaging modalities used during follow-up for the early detection of recurrence and for planning multimodality treatment have contributed to increasing the survival rate. 相似文献
77.
A levitation method has been introduced which uses 8-shape levitation coils arranged on the vertical surface of the guideway. These coils can act as a guidance means as well as the levitation means. The characteristics of this system are examined using numerical examples and experimental data. The cables connecting right and left coils are not connected to a high-voltage power source unlike the usual guidance system which is combined with propulsion. Thus the electric insulation of the cables is not a problem at present. Numerical examples show that the levitation characteristics of the combined levitation and guidance system are almost the same as in the system without the guidance function, and that it attains reduced running resistance with necessary guidance stiffness obtained. A test run was done at Miyazaki Test Line equipped with coils of this type arranged about 120 m, and the results show stable running and balanced displacement which agrees with calculated values. 相似文献
78.
R Abe A Tsuchiya H Koie K Ono S Abo K Saito M Tsukamoto T Sato S Mori K Kikuchi 《Canadian Metallurgical Quarterly》1994,17(2):103-108
Social competence in subjects at risk for schizophrenia and affective disorder and in normal-comparison subjects was examined in childhood and adolescence. Based on interviews with the parents of the subjects and with the children and adolescents themselves, subjects at risk for schizophrenia had poorer overall social competence than subjects at risk for affective disorder and comparison subjects in early adolescence and adolescence but not in childhood. In analyses of specific aspects of social competence, the adolescents at risk for schizophrenia had significantly poorer peer relationships and decreased hobbies/interests than the adolescents at risk for affective disorder and the normal-comparison adolescents. With respect to school adjustment, however, the two groups of adolescent offspring of parents with psychiatric disorders had significantly poorer adjustment than the comparison adolescents but did not differ from each other on this measure. These results suggest that various aspects of poor social competence may precede the onset of schizophrenia and play an important role in its development. 相似文献
79.
Mammary aspergillosis was diagnosed in four flocks of dairy sheep, comprising a total of 1,750 ewes. These animals had been treated prophylactically by intramammary infusion with cloxacillin 5 months prior to lambing. Mammary aspergillosis with concomitant spread to the regional lymph nodes was present in these flocks in a percentage ranging from 2% to 36.4% of treated sheep. Pathologic, bacteriologic, and mycologic studies were performed in seven of the affected ewes. Some of them also had lung, kidney, and liver involvement. The pathologic reaction within lesions ranged from the acute to subacute type, dominated by necrosis and vasculitis with thrombosis, to the chronic granulomatous type, with macrophages and giant cells. The distribution of lesions and the presence of a remarkable vasculitis with fungal thrombi in the mammary gland suggested a hematogenous dissemination of the infection from this organ. Immunologic staining with monoclonal antibody MAb-WF-AF-1, which reacts specifically with Aspergillus hyphae, identified the causative agent in histologic sections of the different affected tissues. The etiologic diagnosis was further supported by the isolation of Aspergillus fumigatus in pure culture from affected tissues and from eight samples of mammary secretions. 相似文献
80.
Kumaki S. Takata H. Ajioka Y. Ooishi T. Ishihara K. Hanami A. Tsuji T. Watanabe T. Morishima C. Yoshizawa T. Sato H. Hattori S. Koshio A. Tsukamoto K. Matsumura T. 《Solid-State Circuits, IEEE Journal of》2002,37(3):450-454
A scalable single-chip 422P@ML MPEG-2 video, audio, and system encoder LSI for portable 422P@HL system is described. The encoder LSI is implemented using 0.13-μm embedded DRAM technology. It integrates 3-M logic gates and 64-Mb DRAM in an area of 99-mm2. The power consumption is suppressed to 0.7 W by adopting a low-power DRAM core. It performs real-time 422P@ML video encoding, audio encoding, and system encoding with no external DRAM. Furthermore, the encoder LSI realizes a 422P@HL video encoder with multichip configuration, due to its scalable architecture. This results in a PC-card size 422P@HL encoder for portable HDTV codec system 相似文献