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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.
Haruo Mimura Ryusei Sato Yu Sasaki Yuichi Furuyama Akira Taniike Kazutoshi Yoshida Akira Kitamura 《International journal of molecular sciences》2008,9(10):1989-2002
Tributyltin (TBT) released into seawater from ship hulls is a stable marine pollutant and obviously remains in marine environments. We isolated a TBT resistant marine Pseudoalteromonas sp. TBT1 from sediment of a ship’s ballast water. The isolate (109.3 ± 0.2 colony-forming units mL−1) adsorbed TBT in proportion to the concentrations of TBTCl externally added up to 3 mM, where the number of TBT adsorbed by a single cell was estimated to be 108.2. The value was reduced to about one-fifth when the lysozyme-treated cells were used. The surface of ethanol treated cells became rough, but the capacity of TBT adsorption was the same as that for native cells. These results indicate that the function of the cell surface, rather than that structure, plays an important role to the adsorption of TBT. The adsorption state of TBT seems to be multi-layer when the number of more than 106.8 TBT molecules is adsorbed by a single cell. 相似文献
8.
This paper proposes an efficient method to develop requirement specifications for Plant Control Software (PCSW) using software-component-based prototypes. Prior to this proposal, domain analyses were conducted on existing PCSWs, and their functions were classified into “similar functions” and “individual functions”. Then PCSW Software Components (PSC: PCSW Software Component, PSCs: PCSW Software Components) were developed to correspond to these functions. PSCs as parameter-style components were developed in order to satisfy the clients’ (we define clients as owners, managers and operators of plants) requirements. A support environment for developing requirement specifications was developed. The environment consists of the Prototype Development Tool (PDT), the Behavior Check Simulator (BCS) and the Requirement Specification Development Tool (RSDT). The method consists of four steps. In the first step, PDT is used to define the parameters to customize PSCs and to compose a PCSW prototype by setting these parameters to PSCs. In the second step, BCS is used to execute the composed PCSW prototype and check its behavior and relevancy against the clients’ expectations. In the third step, steps 1 and 2 are repeated until the behavior of the PCSW prototype satisfies the clients’ requirements. Finally, a requirement specification is developed from the PCSW prototype which fully reflects the clients’ requirements. In order to evaluate the proposed method, it has been applied in five development cases. A Requirement Coverage of 91%, a Requirement Revision Rate of 6%, a PSC Reuse Rate of 92% and a LOC Reuse Rate of 83% have been achieved. In addition, a reduction of 55% in the amount of time required to develop requirement specifications has been achieved. These results indicate that the proposed method has sufficient capability to develop an exhaustive and an adequate PCSW requirement specification. And the developed PSCs have sufficient functions and capability to compose PCSW prototypes, and the support environment is capable of shortening the time taken to develop requirement specifications. 相似文献
9.
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
10.
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