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51.
A new frequency divider, called differential injection locking, is proposed. The proposed divider has no transistor stacking to suppress the performance degradation due to supply voltage reduction. It is shown that the proposed frequency divider achieves 2 GHz with 1 V supply voltage and 540 /spl mu/W power consumption. 相似文献
52.
On‐Line Detection Of State‐Of‐Charge In Lead Acid Battery Using Radial Basis Function Neural Network
To realize a stable supply of electric power in an automobile, an accurate and reliable detection method of SOC (state‐of‐charge) in a lead acid battery is required. However the dynamics of the battery is very complicated. The characteristics of the battery greatly change due to its degradation. Moreover a automobile has many driving patterns, which are unknown beforehand. Thus it is not easy to detect the SOC analytically. In this paper, to overcome this problem, a new on‐line SOC detection method with a radial basis function neural network is proposed. In order to increase the detection accuracy of degraded batteries, physical values related to the degradation degree are used as input signal in the neural network. The detection accuracies for different sized batteries and various degradation states are investigated. 相似文献
53.
Chemically derived epitaxial thin films of YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// (YBCO) are fabricated on [001]LaAlO/sub 3/ substrates by the metalorganic-deposition (MOD) process, which has advantages of high quality, nonvacuum, low-cost, and large-scale production of high-T/sub c/ superconducting films. The MOD-derived YBCO films have a sharp transition at the critical temperature (90.4 K) and a high-quality film with a surface resistance of 0.13 m/spl Omega/ (30 K, 9.98 GHz) is obtained. As a microwave application, simple and compact bandpass filters (BPFs) using /spl lambda//4 coplanar-waveguide. stepped-impedance resonators are demonstrated on the YBCO films. A two-stage Chebyshev BPF of center frequency of 5.731 GHz, bandwidth of 135 MHz, and insertion loss of 0.29 dB with little input power dependency in a power range less than 10 dBm is realized on the film. 相似文献
54.
Takakazu Yamamoto Kouichi ShiraishiMahmut Abla Isao YamaguchiL.“Bert” Groenendaal 《Polymer》2002,43(3):711-719
Neutral and non-doped poly(3,4-ethylenedioxythiophene), PEDOTh(Ni), and its hexyl derivative, PEDOTh-C6(Ni), have been prepared by organometallic dehalogenation polycondensation of 2,5-dichloro-3,4-ethylenedioxythiophene and its hexyl derivative with a zerovalent nickel complex. PEDOTh-C6(Ni) was soluble in organic solvents and 1H NMR data indicated that it had an Mn of 11,000. MALDI-TOF mass analysis of PEDOTh(Ni) gave Mn and Mw of about 1700 and 2400, respectively. PEDOTh-C6(Ni) showed a UV-Vis absorption peak at 546 nm in CHCl3. Electrochemical oxidation of PEDOTh-C6(Ni) started at about −0.40 V vs Ag+/Ag and gave a peak at 0.20 V vs Ag+/Ag. Chemical and electrochemical oxidation (or p-doping) of PEDOTh-C6(Ni), both in solutions and in a solid state, led to weakening of the original π-π∗ peaks and rise of new peak(s) in a region of 800-1500 nm. The p-doping of PEDOTh-C6(Ni) caused not only a decrease in the intensity of 1H NMR signals of the bridging ethylene hydrogens but also a decrease in that of the hexyl side chain, suggesting a strong interaction of the p-dopant with the side chain. NMR data of poly(3-methoxythiophene-2,5-diyl) also supported an assumption that p-doping brings about a severe change in electronic state of the substituent attached to the polythiophene main chain. PEDOTh(Ni) had a density of 1.71 g cm−3; the molecular packing mode of PEDOTh(Ni) is discussed based on the density of the polymer and its XRD data. 相似文献
55.
M Katsuragi K Yamamoto T Tashiro H Nishihara K Toudou 《Canadian Metallurgical Quarterly》1993,34(12):2182-2184
A myocardial 201TI SPECT examination was conducted both prior to and following surgery of two adult patients with an anomalous left coronary artery originating from the pulmonary artery (Bland-White-Garland syndrome). In this syndrome, the anterior wall is usually affected first. Preoperative examination demonstrated an inferoposterior perfusion defect. In both patients, the right coronary artery was markedly dilated, and a significant left-to-right shunt formation was observed. Both patients were diagnosed as possibly having coronary steal syndrome. A prolonged inadequate blood supply to the right coronary region may cause inferoposterior cardiomyopathy. In the postoperative examination, myocardial perfusion markedly improved in one patient whose preoperative SPECT showed redistribution in a delayed scan. Thallium-201 SPECT was therefore found to be useful in assessing both the preoperative and postoperative myocardial perfusion. 相似文献
56.
C Abe S Hirano K Wakazono T Mase R Yamamoto M Matsufuji N Sakata N Agata H Iguchi M Ishizuka 《Canadian Metallurgical Quarterly》1995,17(5-6):175-180
Cytogenin, 8-hydroxy-3-hydroxymethyl-6-methoxyisocoumarin, has low cytotoxicity on murine and human tumour cells in vitro. It augments or suppresses phagocytosis of macrophages and lymphocyte proliferation. It has been reported that cytogenin has a potent inhibitory effect clinically on adjuvant arthritis in Lewis rats and on type II collagen-induced arthritis in DBA/1J mice. Our experimental findings provide evidence that cytogenin has beneficial effects on spontaneous polyarthritis in MRL/1 mice and pristane-induced arthritis in DBA/1J mice. The results suggest that the mode of the anti-arthritic action of cytogenin is different from those of NSAIDs; although the precise mode of action remains unclear, cytogenin may become an excellent therapeutic agent for rheumatoid arthritis. 相似文献
57.
Parameters affecting the frequencies of transformation and co-transformation with synthetic oligonucleotides in yeast. 总被引:7,自引:0,他引:7
T Yamamoto R P Moerschell L P Wakem D Ferguson F Sherman 《Yeast (Chichester, England)》1992,8(11):935-948
Factors influencing the direct transformation of the yeast Saccharomyces cerevisiae with synthetic oligonucleotides were investigated by selecting for cyc1 transformants that contained at least partially functional iso-1-cytochrome c. Approximately 3 x 10(4) transformants, constituting 0.1% of the cells, were obtained by using 1 mg of oligonucleotide in the reaction mixture. Carrier, such as heterogeneous oligonucleotides, enhanced transformation frequencies. Transformation frequencies were dramatically reduced if the oligonucleotides had a large number of mismatches or had terminally located mismatches. Transformation with oligonucleotides, but not with linearized double-strand plasmid, was efficient in a rad52- strain, suggesting that the pathway for transformation with oligonucleotides is different from that with linearized double-strand plasmid. We describe a procedure of co-transformation with two oligonucleotides, one correcting the cyc1 defect of the target allele in the host strain, and the other producing a desired amino acid alteration elsewhere in the iso-1-cytochrome c molecule; approximately 20% of the transformants obtained by co-transformation contained these desired second alterations. 相似文献
58.
59.
Koga H. Yamamoto H. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2005,51(4):1546-1555
This correspondence is concerned with asymptotic properties on the codeword length of a fixed-to-variable length code (FV code) for a general source {X/sup n/}/sub n=1//sup /spl infin// with a finite or countably infinite alphabet. Suppose that for each n /spl ges/ 1 X/sup n/ is encoded to a binary codeword /spl phi//sub n/(X/sup n/) of length l(/spl phi//sub n/(X/sup n/)). Letting /spl epsiv//sub n/ denote the decoding error probability, we consider the following two criteria on FV codes: i) /spl epsiv//sub n/ = 0 for all n /spl ges/ 1 and ii) lim sup/sub n/spl rarr//spl infin///spl epsiv//sub n/ /spl les/ /spl epsiv/ for an arbitrarily given /spl epsiv/ /spl isin/ [0,1). Under criterion i), we show that, if X/sup n/ is encoded by an arbitrary prefix-free FV code asymptotically achieving the entropy, 1/nl(/spl phi//sub n/(X/sup n/)) - 1/nlog/sub 2/ 1/PX/sup n/(X/sup n/) /spl rarr/ 0 in probability as n /spl rarr/ /spl infin/ under a certain condition, where P/sub X//sup n/ denotes the probability distribution of X/sup n/. Under criterion ii), we first determine the minimum rate achieved by FV codes. Next, we show that 1/nl(/spl phi//sub n/(X/sup n/)) of an arbitrary FV code achieving the minimum rate in a certain sense has a property similar to the lossless case. 相似文献
60.
Relatively uniform polymeric microspheres, the coefficients of variation being close to 10%, were obtained by the BPO-initiated suspension polymerization of styrenic monomers. Unlike the conventional stirred-tank system, a particular microporous glass membrane (SPG) provided uniform monomer droplets continuously when monomer was allowed to permeate through the micropores. The monomer droplets were suspended in an aqueous solution containing the stabilizing agents, transferred to a stirred vessel, and polymerized. Up to 10μm spheres, of a far narrower size distribution than those obtained by conventional microsuspension polymerization spheres, were obtained. The initial droplet size and distribution were retained with the successful suppression of secondary particle nucleation by the addition of hydroquinone in the aueous phase. Crosslinked polystyrene spheres were also synthesized in the presence of various low-molecular-weight diluents. While a good solvent, toluene, was not so effective; poor solvents, n-heptane and n-heptane, easily yielded the microporous structure, the specific surface area being as high as 160 m2/g. © 1994 John Wiley & Sons, Inc. 相似文献