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991.
Desulphurization of fifteen US coals of rank ranging from anthracite to sub-bituminous B and five high-temperature chars by carbon monoxide and other gases and gas mixtures between 400 and 600 °C has been studied. The sulphur content of the parent coals ranged between 3.0 and 7.3% and that of the chars between 1.3 and 3.8% by weight. A comparison between air, nitrogen, carbon monoxide, and steam-carbon monoxide mixtures as desulphurizing gases shows the order of desulphurizing ability as . 相似文献
992.
Summary A water insoluble azo-containing polyelectrolyte (PEAPB6P-AC) was successfully fabricated into multilayer films based on the layer-by-layer adsorption technique by using N, N-dimethylformamide (DMF) as the assembling media. The multilayer growth and structure were studied with UV-vis spectroscopy, and the multilayer surface were imaged with Atomic Force Microscopy and compared with that fabricated in water. The results show that assembling PEAPB6P-AC in DMF can effectively eliminate the hydrophobic aggregation of the azo units and consequently results in a much smoother multilayer surface than that fabricated in water. This improvement to the layer-by-layer adsorption technique, which can avoid some major difficulties faced when assembling hydrophobic polyelectrolytes in aqueous solutions, seems to be a versatile way to fabricate high quality multilayer films when using the hydrophobic even water-insoluble polyelectrolytes as assembling units. 相似文献
993.
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995.
Li-Jia Li Hao Su Yongwhan Lim Li Fei-Fei 《International Journal of Computer Vision》2014,107(1):20-39
It is a remarkable fact that images are related to objects constituting them. In this paper, we propose to represent images by using objects appearing in them. We introduce the novel concept of object bank (OB), a high-level image representation encoding object appearance and spatial location information in images. OB represents an image based on its response to a large number of pre-trained object detectors, or ‘object filters’, blind to the testing dataset and visual recognition task. Our OB representation demonstrates promising potential in high level image recognition tasks. It significantly outperforms traditional low level image representations in image classification on various benchmark image datasets by using simple, off-the-shelf classification algorithms such as linear SVM and logistic regression. In this paper, we analyze OB in detail, explaining our design choice of OB for achieving its best potential on different types of datasets. We demonstrate that object bank is a high level representation, from which we can easily discover semantic information of unknown images. We provide guidelines for effectively applying OB to high level image recognition tasks where it could be easily compressed for efficient computation in practice and is very robust to various classifiers. 相似文献
996.
Lianhang Ma Hao Huang Qinming He Kevin Chiew Zhenguang Liu 《Journal of Intelligent Information Systems》2014,43(1):183-203
Local community detection aims at finding a community structure starting from a seed which is a given vertex in a network without global information, such as online social networks that are too large and dynamic to ever be known fully. Nonetheless, the existing approaches to local community detection are usually sensitive to seeds, i.e., some seeds may lead to missing of some true communities. In this paper, we present a seed-insensitive method called GMAC and its variation iGMAC for local community detection. They estimate the similarity among vertices by investigating vertices’ neighborhoods, and reveal a local community by maximizing its internal similarity and minimizing its external similarity simultaneously. Extensive experimental results on both synthetic and real-world data sets verify the effectiveness of our algorithms. 相似文献
997.
石油钻采机械用橡胶气囊的研制 总被引:1,自引:0,他引:1
橡胶气囊是石油钻采设备上常用的一种刹车装置。介绍了橡胶气囊的模具设计、铜气嘴的处理、排气槽的加工布置等整个研制过程。经试验,生产制作的橡胶气囊完全达到设计要求。 相似文献
999.
This paper presents a data-driven modeling and optimization method for cavity filters, according to a limited amount of measurement data. In the method, a model that reveals the effect of mechanical structure on electrical performance of cavity filters is firstly developed by an improved algorithm, which can increase the modeling accuracy of small data set by incorporating multi-kernel and prior knowledge into the framework of linear programming support vector regression. Then, an approach to optimize the structure of cavity filters is formulated by using the developed data-based model, and the obtained results can assist the fabrication of the same filter in the future. Some experiments from a synthetic example and a practical application of cavity filter have been carried out, and the experimental results confirm the effectiveness of the method. The model is particularly suited to a computer-aided manufacturing of volume-producing filters, and the proposed algorithm shows great potential in some applications where the experimental data are very few and the prior knowledge is available. 相似文献
1000.