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81.
本文在Kantorovich型定理的条件下,给出了一种半离散Newton型分裂方法的存在性收敛性定理. 相似文献
82.
通过热失重(TGA)测试,研究了不同阻燃剂改性PP的热分解动力学,结果表明阻燃剂APP、MQ树脂的介入能不同程度提高了改性PP的分解活化能,其中APP改性PP活化能可达500 kJ.mol-1,说明阻燃性能的提高可能归因于无卤阻燃剂促成了改性PP分解活化能的提高。 相似文献
83.
文章分析了当前以平衡与截裁为代表的大系统降维理论,鉴于其内容不尽完善,因此基于系统运动模态的特征,在科技与哲理的辩证分析基础上,建立了大系统派生模态理论和组合降维模型。对于工程实际中的系统响应曲线,提出了基于局域波分解的大系统派生模态提取策略实现系统降维。仿真结果表明,基于模态和图形的协同算法应用简便,并可获得较高精度的降维模型。 相似文献
84.
LI Qiang School of Physics Science Technology Xinjiang University Urumqi China 《中国科学E辑(英文版)》2009,(7)
Nanostructured Fe40Ni40P14B6 alloy ingots of 3―5 mm in diameter could be synthesized by a metastable liquid state spinodal decomposition method. For undercooling T> 260 K, the microstructure of the undercooled specimen had exhibited liquid state spinodal decomposition in the undercooled liquid state. The microstructure could be described as two intertwining networks with small grains dispersed in them. For undercooling T>290 K, the overall microstructure of the specimen changed into a granular morphology. T... 相似文献
85.
提出了一种鲁棒性数字水印和脆弱性数字水印相结合的复合式水印算法,具有较好的双重保护性能,即用于版权认证方面的鲁棒性数字水印和用于图像内容保护的脆弱性数字水印.首先,对原始图像进行DDWT和SVD变换在频域中嵌入鲁棒性数字水印;然后,在空域中嵌入脆弱性数字水印.仿真实验表明,该算法具有很好的应用前景. 相似文献
86.
The sulfur tolerance of a barium-containing NOx storage/reduction trap was investigated using infrared analysis. It was confirmed that barium carbonate could be replaced by barium sulfate by reaction with low concentrations of sulfur dioxide (50 ppm) in the presence of large concentrations of carbon dioxide (10%) at temperatures up to 700 °C. These sulfates could at least be partially removed by switching to hydrogen-rich conditions at elevated temperatures. Thermodynamic calculations were used to evaluate the effects of gas composition and temperature on the various reactions of barium sulfate and carbonate under oxidizing and reducing conditions. These calculations clearly showed that if, under a hydrogen-rich atmosphere, carbon dioxide is included as a reactant and barium carbonate as a product then barium sulfate can be removed by reaction with carbon dioxide at a much lower temperature than is possible by decomposition to barium oxide. It was also found that if hydrogen sulfide was included as a product of decomposition of barium sulfate instead of sulfur dioxide then the temperature of reaction could be significantly lowered. Similar calculations were conducted using a selection of other alkaline-earth and alkali metals. In this case calculations were simulated in a gas mixture containing carbon monoxide, hydrogen and carbon dioxide with partial pressures similar to those encountered in real exhausts during switches to rich conditions. The results indicated that there are metals such as lithium and strontium with less stable sulfates than barium, which may also possess sufficient NOx storage capacity to give sulfur-tolerant NOx traps. 相似文献
87.
针对电网运行可靠性评估计算量大,但又要求计算时间短的问题,提出了一种基于分布式计算的电网运行可靠性评估算法。该算法采用改进的状态选择和分析方案,解决了计算终端间随机数序列的关联性问题,有效地降低了通信量,提高了计算速度。基于该算法编制的评估软件已通过RTS-24系统和某省级电网的实际运行测试,测试结果表明,该算法不仅能够有效评估电网运行可靠性,而且计算速度随计算终端数增加呈一定倍数提高。 相似文献
88.
Results of studying thermal decomposition of ammonium perchlorate (AP) samples in the original form and after irradiation
by γ-quanta of 60Co by methods of differential scanning calorimetry and dynamic thermogravimetry with heating rates b = 0.1–0.3 K/sec are described. Irradiation is performed in air at a temperature of 298 ± 2 K and a dose rate of ≈0.2 Gy/sec
in the range of absorbed doses D = 0–150 kGy. Preliminary irradiation is demonstrated to lead to substantial transformations of the pattern of thermal decomposition
of ammonium perchlorate in the dynamic regime of heating: the single-stage process of decomposition of non-irradiated samples
proceeding at b = 0.107 K/sec in the temperature range of 625 to 743 K is replaced by a multistage process. At D = 150 kGy, exothermal transformations accompanied by noticeable losses of sample mass are observed starting from 473 K. Within
experimental errors, the total thermal effect of AP decomposition is found to be independent of the absorbed dose and amounts
to −1150 kJ/kg on the average.
__________
Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 6, pp. 69–74, November–December, 2007. 相似文献
89.
提出一种新的基于多分辨率奇异值分解( MSVD)图像融合算法。算法对源图像进行MSVD处理,使其分解为互不相关的平滑和细节分量,并对平滑分量进行多层次的分解与处理。类似于小波变换,多分辨率奇异值分解的基本思想是在平滑分量的每一层上用奇异值分解( SVD)来取代滤波,最终利用融合规则对图像进行MSVD融合。利用5种评价算子来评价算法,得到的融合效果很好。与基于小波分解的算法相比,算法计算简单、实时性突出,对复杂、高像素图像处理更简单方便。 相似文献
90.
Image decomposition refers to the splitting of an image into two or more components.In this paper,a clean image is separated into two parts:one is the cartoon component,consisting only of geometric structure,and the other is the oscillatory component,consisting of texture.Three parts for noisy image are considered:cartoon,texture,and noise.To better decompose an image,we propose two new variational models.In our models,two adaptive regularization terms are introduced.The two regularization terms are determined by an adaptive function which can discriminate the cartoon and texture of an image automatically.Experimental results illustrate the efectiveness of the proposed models for image decomposition. 相似文献