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1.
Takauchi H. Tamura H. Matsubara S. Kibune M. Doi Y. Chiba T. Anbutsu H. Yamaguchi H. Mori T. Takatsu M. Gotoh K. Sakai T. Yamamura T. 《Solid-State Circuits, IEEE Journal of》2003,38(12):2094-2100
We describe a CMOS multichannel transceiver that transmits and receives 10 Gb/s per channel over balanced copper media. The transceiver consists of two identical 10-Gb/s modules. Each module operates off a single 1.2-V supply and has a single 5-GHz phase-locked loop to supply a reference clock to two transmitter (Tx) channels and two receiver (Rx) channels. To track the input-signal phase, the Rx channel has a clock recovery unit (CRU), which uses a phase-interpolator-based timing generator and digital loop filter. The CRU can adjust the recovered clock phase with a resolution of 1.56 ps. Two sets of two-channel transceiver units were fabricated in 0.11-/spl mu/m CMOS on a single test chip. The transceiver unit size was 1.6 mm /spl times/ 2.6 mm. The Rx sensitivity was 120-mVp-p differential with a 70-ps phase margin for a common-mode voltage ranging from 0.6 to 1.0 V. The evaluated jitter tolerance curve met the OC-192 specification. 相似文献
2.
Katsuta G. Muraoka K. Inoue N. Sakai S. Tsunekage T. Ando K. 《Power Delivery, IEEE Transactions on》1992,7(1):1-9
A fault section detection system that uses optical magnetic field sensors and instantly detects the section in which a ground fault occurred was developed for 66 kV underground multiterminal systems having Y-branch joint boxes. The optical magnetic field sensor, which is based on the Faraday effect in Bi-doped YIG ((BiYbGd)3Fe5O12) having a large Verdet constant, detects cable conductor currents of 0 to 2000 A with high precision with the use of a laminated magnetic ring core of silicon steel plates. Sensors and a fault section detector/indicator of a system are connected with optical fibers capable of nonrepeated transmission of over 6 km 相似文献
3.
Sakai T. Kobayashi K. Kubota S. Morikura M. Kato S. 《Selected Areas in Communications, IEEE Journal on》1995,13(2):285-290
Diversity combining methods for mobile satellite communication systems employing convolutional encoding and soft-decision Viterbi decoding are evaluated. Computer simulation clarifies that the pre-Viterbi-decoding maximal ratio combining method has better performance than other methods in Rician fading channels. The simulation results agree with the Pe (bit error probability) performance derived from the numerical analysis for slow fading using the approximate Pe performance of Viterbi decoding in AWGN (additive white Gaussian noise) channels and the probability density function of Rician fading. Applying this diversity method to the multi-beam mobile satellite communication systems, a satellite beam diversity reception scheme is proposed. A computer simulation result shows that the proposed scheme decreases the packet error rate of the control signals to less than 1/100 around the satellite beam boundary 相似文献
4.
5.
An inversion relationship is clarified between lightness and brightness, and also between chroma and colorfulness under nonuniform illumination with different illuminance levels (high and low) within the same visual field. Brightness (or colorfulness) of object color with low lightness (or chroma) under high illuminance level is perceived higher than that of another object color with high lightness (or chroma) under low illuminance level. Two color images are given for showing the inversion phenomena on brightness–lightness and colorfulness–chroma between object colors under different illuminance levels. These color images are useful for making researchers on color understand the differences in concept between brightness and lightness, and also between colorfulness and chroma. In particular, the concept of colorfulness is important, but difficult to understand. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 372–377, 2007 相似文献
6.
A novel elastic polymer containing 4,4′-bipyridinium salts with tetrakis[3,5-bis(trifluoromethyl)phenyl]borate as part of the main chain was synthesized. The cast film showed persistent and reversible colour changes due to photoinduced electron transfer upon excitation of an ion-pair charge-transfer band (ex >365 nm) in vacuo. The lifetime of the coloured state markedly depended on temperature. The optically written data were stored without decay below 0°C and were erased thermally at elevated temperatures. The colour changes were reversibly repeatable for many times. 相似文献
7.
We clarified the roles of IL-1 beta in peripheral neural regeneration after axotomy in a three-dimensional collagen gel culture system ranging from a single neurone to a dorsal root ganglion (DRG) explant with its associated nerve bundles. Application of 30 U/ml IL-1 beta to the culture systems clearly enhanced neural regeneration. This regeneration was evident in transected nerve terminals of DRG explants with or without associated nerve bundles, but not in dissociated single neurones. Neural survival was not affected by IL-1 beta in any of these culture systems. These results suggest that IL-1 beta stimulates surrounding non-neuronal cells to secrete neurotrophic factors, thus enhancing neurite regeneration from transected nerve terminals in cultured adult DRG explants. 相似文献
8.
BACKGROUND: Foot complications in diabetes incur huge human and medical costs. There is a high incidence of complicated diabetes mellitus in Far North Queensland, particularly in the indigenous communities. METHODS: An audit of 51 patients admitted to Cairns Base Hospital from July 1992 to December 1994 with diabetic foot complications requiring surgical intervention was performed. RESULTS: The majority of surgical procedures were for serious infections in neuropathic feet precipitated by minor trauma. Surgical procedures included debridement/drainage, minor amputation, major amputation and arterial bypass. Half of the patients required more than one procedure and/or multiple admissions. Average length of stay was 48 days. Indigenous patients were overrepresented in this audited group. CONCLUSIONS: Prevention or minimization of diabetic foot complications can be achieved only through improvement in education and vigilance at all levels of the treatment process from community to hospital. Special attention to the needs of indigenous communities with a high incidence of diabetes must be a feature of any future initiatives. 相似文献
9.
T Sakai A Konishi T Nishiyama T Higashizawa H Bito 《Canadian Metallurgical Quarterly》1998,47(8):998-1001
Effectiveness in visualization of the vocal cord during orotracheal intubation with McCoy (McC) compared with Macintosh (Min) and Miller (Mil) blades were investigated. After an institutional review board approval, 117 patients for elective surgery under general anesthesia requiring tracheal intubation were investigated. Five board certified anesthesiologists tried to visualize the vocal cord of a patient three times with the three different types of laryngoscope. Total of 351 intubation attempts were studied. The view obtained at laryngoscopy with each of the three blades was recorded as follows. Grade 1. If most of the glottis is visible. Grade 2. If only the posterior extremity of the glottis is visible. Grade 3. If no part of the glottis can be seen. Grade 4. If not even the epiglottis can be exposed. Eight-two Grade 1 views were obtained with McC, 72 with Mil and 47 with Min, respectively. Thirty-three Grade 2 views were obtained with McC, 36 with Min and 24 with Mil. Two Grade 3 views with McC, 34 with Min and 14 with Mil were obtained. Seven Grade 4 views were obtained with Mil. The grades of laryngeal visualization with McC were significantly lower than those with Min and Mil. 相似文献
10.
Akihiro Yamada Kuniko Kojima Koji Minami Hiroaki Sugiura Hiroshi Kida Kenji Samejima 《Journal of the Society for Information Display》2012,20(7):390-396
Stationary projectors mainly used in system applications have recently gained a wider application range, including general presentations in halls and large conference rooms and being used, for example, in digital signage and for monitoring purposes. Consequently, they are required to meet new market demands for durability, reliability, and flexibility in installation in addition to their conventional basic performance such as especially high brightness. To achieve especially high brightness, a new optical system with two lamps is proposed; the profile of the cover glass that prevents the glass from scattering is made aspherical, the profile of the beam‐combining mirror is improved with its position optimized, and the size of the incident plane of the integrator rod is made larger (1.1 times). These measures resulted in an optical system of an even higher efficiency with 7000 lm, which is the highest in its class (according to a June 2010 investigation). Also, the arrangement of two parallel lamps completely eliminated the effect of heat passing from one lamp to the other, which helped secure durability, reliability, and flexibility in installation. Furthermore, the combined use of the unique non‐telecentric optical system, adopted from the conventional single‐lamp model, helps maintain the class‐highest contrast ratio.1,2 相似文献