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971.
Knowledge of the camera trajectory, which may be determined from the motions between consecutive frames of a video clip, can be used to register images for constructing image mosaics. We discuss a mosaic-based positioning framework for building photo-mosaics and concurrently utilizing them for improved positioning. In this approach, the mosaic is directly exploited in bounding the accumulation of position errors as we integrate the incremental motions of the camera. It is also shown that two earlier closed-form solutions for the estimation of motion directly from spatio-temporal image gradients, as for most gradient-based techniques based on the application of linear(ized) image motion constraint equations, are corrupted with systematic biases. These can be reduced significantly by incorporating the higher-order terms. We propose recursive methods to solve the new nonlinear constraint equations, and investigate the performance of the new solutions in a number of experiments with synthetic and real data 相似文献
972.
用铁屑微电池原理深度处理了医院废水 ,分析了废水pH、铁屑用量、反应时间对处理效果的影响。结果表明 ,最佳的反应条件为 :废水进水pH为 3.5 ,铁屑用量为 12 .5 % ,常温反应 80min。 相似文献
973.
Zhong-Quan Qu Shuai Wang Cheng-Lin Xu XiaoYu Zhang Ming-Guo Sun Chun-Lan Jin National Astronomical Observatories/Yunnan Astronomical Observatory Chinese Academy of Sciences Kunming zqqu@vip.km.net Graduate School of the Chinese Academy of Sciences Beijing 《中国天文和天体物理学报》2005,5(4):426-432
We analyze the spectral line broadening of those magneto-sensitive lines in solar magnetized atmospheres. The broadening at the line wings is due to the increase of the effective width of energy levels involved in Zeeman splitting, and the broadening at the line core also originated in Zeeman splitting under the condition that the Zeeman components are mixed. Therefore, the magnetoinduced or Zeeman broadening take effects on the whole line. The observed Stokes parameter data in a sunspot and outside it acquired by Solar Stokes Spectrum Telescope (S3T) are analyzed for the demonstration of this mechanism, and the Zeeman broadening rates are calculated for FeI6302.5 under some assumptions. Our result shows that the broadening is increased as the magnetic field strength becomes stronger, but the rate of increase at the line core is decreased as the field strength increases, while the rate at the wing does not show such an obvious regularity. The broadening is more effective in the line core than in the wings. 相似文献
974.
975.
The spatial division of industries of the pearl river delta in the 1990s: Characteristics and trends
The article analyzed the spatial division of industries of the Pearl River Delta (PRD) in the 1990s, a period that witnessed
the deepening of the reform and opening policies and continued rapid development of the region. By adopting the index of specialization,
the extent of specialization, its change and its spatial distribution in the region are measured and demonstrated. The research
revealed that, despite the trend of more balanced development of the secondary sector between the PRD and the rest of the
province, in the PRD, it is the unbalanced development that dominated and the spatial division of the secondary sector has
been shaped. The tertiary industry has also been experiencing unbalance development and the spatial division of the tertiary
sector has been emerging, its extent of concentration appearing even more evident than that of the secondary sector. The author
also discussed the linkage between the spatial division of the two sectors. In the end of the paper, the trends of the spatial
division of the industries in the PRD are forecasted.
Foundation item: Under the auspices of the National Natural Science Foundation of China (No. 49831030).
Biography: XU Yong-jian (1972 – ), female, a native of Changsha City, Ph. D.. Her research interest includes urban geography. 相似文献
976.
977.
Song Guo-xuan Yan Hao-jian Xu Tong-qi Zhu Shi-chang 《Chinese Astronomy and Astrophysics》1981,5(3):332-336
We have found an interior solution of the Einstein equation containing a vector graviton field under a special mass distribution. 相似文献
978.
979.
Three varieties of goldfish, the Red-dragon, the Red-carassius and the Eggfish, were used to demonstrate the influence of nucleus and cytoplasm on the phenotypic expression and their mutual interaction after nuclear transplantation. Fishes from these combinations could not only develop normally but also reach sexual maturity.The characteristics of fishes after first transplantation (N_1) were fundamentally of the nuclear donor variety e. g. the combination of nucleus of Red-dragon with cytoplasm of Redcarassius was very much similar to Red-dragon. The male fish of N_1 mated with female Red-dragon gave offsprings with characters fundamentally like the Reddragon too.If these blastulae were used as nuclear donor and transplanted their nuclei into Red-carassius cytoplasm again, we got the N_2. There were more single tailed fishes in this category with the character of the Red-earassius. When the male fish of N_2 mated with the Reddragon, more single tailed and atypical single tailed fishes appeared in their offsprings. This indicated that the changed characteristics in N_2 was inheritable.If proceeded in this manner again and again, more and more single tailed and atypical single tailed fishes appeared in N_3 and N_4 and their offsprings when mated with Red-dragon. The effect of cytoplasm changed not only the phenotypic characters of the combination, but also the genetic information to next generation. Those influence was additive too. 相似文献
980.
A midlatitude squall line passed over the array of the Cooperative Convective Precipitation Experiment (CCOPE) on 1 August
1981. The structure and evolution of the squall line, and the correlations of the storm with surface thermodynamics and kinematic
fields are investigated, mainly by using radar and surface mesonet data in CCOPE. The storm-wide precipitation efficiency
is also estimated.
The squall line was of an obvious process of metabolism. Thirty-four cells formed successively in front of the primary storm
and eventually merged into it during the period 1700-2010 MDT. The newest cells formed near surface equivalent potential temperature
maxima, and near surface moisture flux convergence zones or/ and the “temperature break lines”. The thunderstorm rainfall,
with the precipitation efficiency of 54%, lags 25-30 min behind the moisture flux convergence on the average. 相似文献