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51.
Xixian Chen Suzuki M. Miki N. Nagai N. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1995,41(5):1409-1417
To reduce the system initialization time in high-speed full-duplex data transmission over two-wire lines, we propose an efficient full-duplex fast training algorithm which can simultaneously estimate the impulse responses of echo paths and channels at both ends. Two mutually orthogonal periodic sequences are designed and used to co-estimate the near echo, the far echo with bulk delay, and the channel response. The new algorithm can reduce the tap-setting time to half of that required by the traditional half-duplex fast training schemes. The effects of channel noise and symbol rate offset between two ends are examined in terms of both mean-square error (MSE) and signal-to-noise ratio (SNR). Both the theoretical analysis and computer simulation show that there are three degrading factors due to symbol rate offset. The SNR is inversely proportional to the sum of the estimated coefficients, the half period of the training sequences, and the square of symbol rate offset. If the far-signal-to-channel-noise ratio is 30 dB, then the degradation is significant when the symbol rate offset is more than 10 -4. If it is 40 dB, then the degradation is significant when the symbol rate offset is above 3×10-5 相似文献
52.
Y Nagai T Azuma M Funauchi M Fujita M Umi M Hirano T Matsubara S Ueno 《Canadian Metallurgical Quarterly》1998,157(1):52-59
This study examined the effect of thyrotrophin-releasing hormone (TRH) administration on thermoregulation in the newborn. Twin lambs were either delivered near-term by caesarean section or born vaginally at term. Colonic temperature, O2 consumption, CO2 production, breathing and heart rates, plus plasma thyroid hormone and nonesterified fatty acid (NEFA) concentrations and thermogenic activity (i.e. GDP binding) of brown adipose tissue (BAT) were measured. In caesarean section delivered lambs colonic temperature decreased rapidly after birth, a response that was greater in the group designated for TRH treatment, in which colonic temperature fell to below 36.0 degrees C at 80 min of life, prior to TRH administration. At this age colonic temperature had been restored to a mean of 38.70 degrees C in controls. TRH had no influence on the composition or thermogenic activity of BAT. The incidence of shivering was not influenced by TRH, but treated lambs maintained a higher rate of O2 consumption and ventilation compared with controls after colonic temperature had been restored to 38.56 degrees C. TRH appeared to promote fat oxidation as O2 consumption remained unchanged and CO2 production declined by a greater rate in treated lambs, resulting in a lower respiratory quotient compared to controls. Heart rate and plasma concentrations of NEFA increased following TRH administration although this did not result in values greater than controls. Normothermic lambs born vaginally had BAT with a greater thermogenic activity, higher plasma thyroid hormone and NEFA concentrations compared with caesarean section delivered lambs, but a thermogenic response was not observed to TRH despite a rise in thyroid hormone concentrations. In conclusion, TRH can improve thermoregulation, an effect that could be linked to an increase in fat oxidation. 相似文献
53.
Lung from male and female rats fasted for 4 days were used. Phospholipid, phosphatidylcholine and its molecular species were
analyzed in lungs from these rats and effects of fasting upon the biosynthesis of phosphatidylcholine in lungs from both sexes
were determined using radioactive choline. The molecular species of phosphatidylcholine in both male and female rats did not
differ with fasting except the monoenoic species. Incorporation of choline into phosphatidylcholine in both male and female
rats significantly increased after fasting, but distribution of radioactivity in phosphatidylcholine yielded similar values
in each group. These results suggest that the decrease of saturated phosphatidylcholine content after fasting may be not due
to specific change in saturated phosphatidylcholine. 相似文献
54.
A case of the "Burnett" syndrome complicated by acute renal insufficiency is reported. Hemodialysis and normalization of the diet helped in the end to eliminate both the milk-alkali syndrome and renal insufficiency. 相似文献
55.
Hiroshi Nagai Yoshiki Takebayashi Hiroyasu Mitani 《Metallurgical and Materials Transactions A》1981,12(3):435-442
The isothermal oxidation resistance in air at 1273, 1323, and 1373 K of Fe-20Cr alloys with 1 wt pct dispersoid of Y203, La2O3, A12O3, TiO2, SiO2, Cr2O3 and without dispersoid prepared by a conventional sintering and rolling procedures was examined. It was found that SiO2 dispersoid reduced, while A12O3 dispersoid slightly increased the oxidation resistance. The dispersoids of TiO2 and Cr2O3 showed no beneficial effect on the oxidation resistance except for the oxidation after 10 h at 1373 K. The oxidation behavior
after 10 h at 1373 K was rather complex including accelerated oxidation. The beneficial effect of La2O3 and Y2O3 dispersoids was excellent at all temperatures. The oxidation rates during the early stage of oxidation for the alloys with
dispersoid were apparently dependent on the type of the dispersoid. There was no evidence that dispersoid accumulated at the
scale-alloy interface. Comparison of results obtained for the oxidation of the alloys prepared by a powder metallurgical procedure
with results for the alloys by arc-melting procedure indicated that the grain size of the alloy is an important factor for
reduction of oxidation rate but does not seem to be critical, because the grain size of the alloys with dispersoid was not
dependent on the type of the dispersoid. Ion Microanalyses of the Cr2O3 scale formed after 1 h oxidation at 1373 K showed an interesting feature in that all the dispersed elements were incorporated
in the scale and the iron content of the scale was lower on the alloys which exhibited better oxidation resistance. 相似文献
56.
The tropospheric particle extinction-to-backscatter ratio, the depolarization ratio, and the water-vapor mixing ratio were measured by use of a Raman lidar and a polarization lidar during the Asian dust seasons in 2001 and 2002 in Tsukuba, Japan. The apparent (not corrected for multiple-scattering effects) extinction-to-backscatter ratios (Sp) showed a dependence on the relative humidity with respect to ice (RHice) obtained from the lidar-derived water-vapor mixing ratio and radiosonde-derived temperature; they were mostly higher than 30 sr in dry air (RHice < 50%), whereas they were mostly lower than 30 sr in ice-supersaturated air (RHice > or = 100%), where the apparent extinction coefficients were larger than 0.036 km(-1). Both regions showed mean particle depolarization ratios of 20%-22%. Comparisons with theoretical calculations and the previous experiments suggest that the observed dependence of Sp on RHice is attributed to the difference in the predominant particles: nonspherical aerosols (mainly the Asian dust) in dry air and cloud particles in ice-supersaturated air. 相似文献
57.
The aim of this study is to develop an estimation method for a shape space. In this work, “shape space” means a nonlinear subspace formed by a class of visual shapes, in which the continuous change in shapes is naturally represented. By using the shape space, various operations dealing with shapes, such as identification, classification, recognition, and interpolation can be carried out in the shape space. This paper introduces an algorithm based on a generative model of shapes. A higher-rank of the self-organizing map (SOM2) is used to implement the shape space estimation method. We use this method to estimate the shape space of artificial contours. In addition, we present results from a simulation of omnidirectional camera images taken from mobile robots. Our technique accurately predicts changes in image properties as the robot’s attitude changes. Finally, we consider the addition of local features to our method. We show that the inclusion of local features solves the correspondence problem. These results suggest the potential of our technique in the future. 相似文献
58.
A Phytol‐Enriched Diet Activates PPAR‐α in the Liver and Brown Adipose Tissue to Ameliorate Obesity‐Induced Metabolic Abnormalities 下载免费PDF全文
59.
Masayuki Nagai Tatsuya Saeki Tadashi Nishino 《Journal of the American Ceramic Society》1990,73(5):1456-1460
Hydroxyapatite and Cl− -containing hydroxyapatite powders are prepared and characterized. Reversible substitution of CO2- 3 for OH− at the surface is presumed to be responsible for the sensor function. The role of Cl− , which is necessary to realize the sensor function and is incorporated during soaking treatment, is considered as follows. It may reduce the strain caused by the incorporation of CO2- 3 (which is larger than OH− ), and, hence, promote the reversible substitution reaction. This behavior is presumed because Cl− -containing hydroxyapatite samples exhibit sensor characteristics typical of CO2 without any treatment. 相似文献
60.
Atsushi Yoshida Sho Ohata Tatsuhiro Mori Ryuji Tada Pavla Dagsson-Waldhauserová 《Aerosol science and technology》2016,50(3):1-4
Copyright © 2016 American Association for Aerosol Research 相似文献