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51.
丁锦萍 《山西化工》2002,22(1):31-33
介绍了国外利用天然气生产油口的生产工艺,探讨了山西省利用丰富的煤层气资源发展合成油的可能性和优势,并提出了相应的发展建议。  相似文献   
52.
Adjusting parameters iteratively is a traditional way of training neural networks, and the Rough RBF Neural Networks (R-RBF-NN) follows the same idea. However, this idea has many disadvantages, for instance, the training accuracy and generalization accuracy etc. So how to change this condition is a hot topic in Academics. On the basis of Extreme Learning Machine (ELM), this paper proposes a Weighted Regularized Extreme Learning Machine (WRELM), taking into account both minimizing structured risk and weighted least-squares principle, to train R-RBF-NN. The traditional iterative training method is replaced by the minimal norm least-squares solution of general linear system. The method proposed in this paper, increasing controllability of the entire learning process and considering the structured risk and empirical risk, can improve the performance of learning and generalization. Experiments show that it can reach a very superior performance in both time and accuracy when WRELM trains the Rough RBF Neural Networks in pattern classification and function regression, especially in pattern classification, which can improve the generalization accuracy more than 3.36 % compared with ELM. Obviously, the performance of the method proposed in this paper is better than the traditional methods.  相似文献   
53.
Sparse representation provides a new method of generating a super-resolution image from a single low resolution input image. An over-complete base for sparse representation is an essential part of such methods. However, discovering the over-complete base with efficient representation from a large amount of image patches is a difficult problem. In this paper, we propose a super-resolution construction based on multi-space sparse representation to efficiently solve the problem. In the representation, image patches are decomposed into a structure component and a texture component represented by the over-complete bases of their own spaces so that their high-level features can be captured by the bases. In the implementation, a prior knowledge about low resolution images generation is combined to the typical base construction for high construction quality. Experiment results demonstrate that the proposed method significantly improves the PSNR, SSIM and visual quality of reconstructed high-resolution image.  相似文献   
54.
The benefit of using the geometry image to represent an arbitrary 3D mesh is that the 3D mesh can be re-sampled as a completely regular structure and coded efficiently by common image compression methods. For geometry image-based 3D mesh compression, we need to code the normal-map images while coding geometry images to improve the subjective quality and realistic effects of the reconstructed model. In traditional methods, a geometry image and a normal-map image are coded independently. However a strong correlation exists between these two kinds of images, because both of them are generated from the same 3D mesh and share the same parameterization. In this paper we propose a predictive coding framework, in which the normal-map image is predicted based on the geometric correlation between them. Additionally we utilize the strong geometric correlation among three components of normal-map image to improve the predicting accuracy. The experimental results show the proposed coding framework improves the coding efficiency of normal-map image, meanwhile the realistic effect of a 3D mesh is significantly enhanced.  相似文献   
55.
针对机龄较长的A320飞机多次重复出现DEU B或DEU B 300 RH等故障信息,难以排除故障,本文将研究空客排故手册TSM和图解目录手册IPC中的排故信息,以及编码译码计算机软件和硬件的情况,判断故障的原因,彻底解决这一故障,提高航空器的可靠性,控制维修成本。最终,在大量研究之后,发现是编码译码计算机在互换性和混装性方面出了问题,并经过系统设备优化升级、手册修改等措施,取得了预期的效果。  相似文献   
56.
随着现代社会的进步,科学技术取得了飞速发展,计算机网络得到了大量普及,极大地促进了社会生产和人们生活水平的提高,对社会的整体发展起着至关重要的作用.本次研究将从网络维护、管理的意义和应注意的问题出发,对网络网络维护与管理相关策略进行深入分析和探究.  相似文献   
57.
Lithium manganese oxides LiMn2O4 and rare earth elements doped LiNd0.01Mn1.99O4 were synthesized by microwave method. The structure and the electrochemical performances of the samples were characterized. XRD data shows both samples exhibit the same pure spinel phase. But due to the introduction of Nd3+ ion into the unit cell, the lattice parameter of the Nd-doped spinel was larger than that of the undoped one. The two samples had a similar morphology including small particle size and homogeneous particle distribution as tested by SEM. The cyclic voltammmetry and constant-current charge-discharge tested that Nd-doped spinel displayed a better reversibility and cycleability.  相似文献   
58.
The structure of benzoxazines is similar to that of phenolic resin through thermal self‐curing of the heterocyclic ring opening reaction that neither requires catalyst nor releases any condensation byproduct. These polybenzoxazine resins have several outstanding properties such as high thermal stability and high glass transition temperature. To better understand the curing kinetics of this copolybenzoxazine thermosetting resin, dynamic and isothermal differential scanning calorimetry measurements were performed. Three models, the Kissinger method, the Flynn–Wall–Osawa method, and the Kamal method, were used to describe the curing process. Dynamic kinetic activation energies based on Kissinger and Flynn–Wall–Osawa methods are 72.11 and 84.06 KJ/mol, respectively. The Kamal method based on an autocatalytic model results in a total order of reaction between 2.66 and 3.03, depending on curing temperature. Its activation energy and Arrhenius preexponential are 50.3 KJ/mol and 7959, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 730–737, 2005  相似文献   
59.
动态硫化和非硫化型炭黑填充NBR/PVC共混物的性能   总被引:2,自引:0,他引:2  
  相似文献   
60.
不同线密度粘胶原丝及其碳纤维的结构性能对比   总被引:1,自引:0,他引:1  
用Weibull分析处理 10mm长的 4种不同线密度粘胶原丝和相应碳纤维的单丝断裂强度 ,得到原丝线密度、强度分布和碳纤维强度的对应关系。采用透射电镜 (TEM )和小角X散射 (SAXS)分析粗旦原丝 ,发现孔洞较多 ,并存在大于 70nm的大孔洞。截面和表面照片也揭示出细旦原丝截面相对规整 ,表面较光滑 ,粗旦原丝则反之。结果表明 ,原丝线密度小 ,截面形状圆整 ,缺陷少 ,所制得的碳纤维强度高。  相似文献   
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