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1.
Fine-grained few-shot learning is a difficult task in image classification. The reason is that the discriminative
features of fine-grained images are often located in local areas of the image, while most of the existing few-shotlearning image classification methods only use top-level features and adopt a single measure. In that way, the localfeatures of the sample cannot be learned well. In response to this problem, ensemble relation network with multi-level measure (ERN-MM) is proposed in this paper. It adds the relation modules in the shallow feature space tocompare the similarity between the samples in the local features, and finally integrates the similarity scores from thefeature spaces to assign the label of the query samples. So the proposed method ERN-MM can use local details andglobal information of different grains. Experimental results on different fine-grained datasets show that the proposedmethod achieves good classification performance and also proves its rationality. 相似文献
2.
Jie Gao Zhikai Li Mei Dong Weibin Fan Jianguo Wang 《Frontiers of Chemical Science and Engineering》2020,14(5):847
Coal-based ethanol production by hydration of ethylene is limited by the low equilibrium ethylene conversion at elevated temperature. To improve ethylene conversion, coupling hydration of ethylene with a potential ethanol consumption reaction was analyzed thermodynamically. Five reactions have been attempted and compared: (1) dehydration of ethanol to ethyl ether ( ), (2) dehydrogenation of ethanol to acetaldehyde ( ), (3) esterification of acetic acid with ethanol ( ), (4) dehydrogenation of ethanol to ethyl acetate ( ), and (5) oxidative dehydrogenation of ethanol to ethyl acetate ( ). The equilibrium constants and equilibrium distributions of the coupled reactions were calculated and the effects of feed composition, temperature and pressure upon the ethylene equilibrium conversion were examined. The results show that dehydrogenation of ethanol to acetaldehyde has little effect on ethylene conversion, whereas for dehydrogenation of ethanol to acetaldehyde and ethyl acetate, ethylene conversion can be improved from 8% to 12.8% and 18.5%, respectively, under conditions of H2O/C2H4 = 2, 10 atm and 300°C. The esterification of acetic acid with ethanol can greatly enhance the ethylene conversion to 22.5%; in particular, ethylene can be actually completely converted to ethyl acetate by coupling oxidative dehydrogenation of ethanol. 相似文献
3.
1 IntroductionWiththerapiddevelopmentofInternet,thenetworkisbecominglargerandmorecomplex ,whichcallsformoresophisticatednetworkmanage mentstrategiestobeadoptedinordertoguaranteeadequatelevelsofperformance .Confrontedwiththepresentstatusofnetworkmanagement,manyschol arsmakegreateffortstoinventnewapproachesforthepurposeofimprovingtheperformanceofnet workmanagement.MobileAgenttechnologiesandtheirapplicationtonetworkmanagementaread vancedunderthisbackground .Althoughalotofworkhasstilltobedone ,t… 相似文献
4.
A 320×240 CMOS image sensor is demonstrated,which is implemented by a standard 0.6 μm 2P2M CMOS process.For reducing the chip area,each 2×2-pixel block shares a sample/hold circuit,analog-to-digital converter and 1-b memory.The 2×2 pixel pitch has an area of 40 μm×40 μm and the fill factor is about 16%.While operating at a low frame rate,the sensor dissipates a very low power by power-management circuit making pixel-level comparators in an idle state.A digital correlated double sampling,which eliminates fixed pattern noise,improves SNR of the sensor, and multiple sampling operations make the sensor have a wide dynamic range. 相似文献
5.
YANG Jie WENG Li-na 《通讯和计算机》2007,4(3):60-62
TH-PPM-UWB system of image transmission is presented in this paper. And then the performance analysis over an ideal AWGN (Additive White Gaussian Noise) channel is given. The studies indicate that the selection of parameters has a great influence on BER (Bit Error Rate) of the system, especially the number of pulses per information bit. The simulation results of image transmission demonstrate that a larger number of pulses per information bit will lead to better BER performance. 相似文献
6.
松香胺聚氧乙烯酸对A3钢在盐酸介质中缓蚀性能的研究 总被引:2,自引:0,他引:2
采用失重法及电化学方法测定松香胺聚氧乙烯醚化合物(以下简称RA)在盐酸溶液中对A3钢的缓蚀性能,研究了温度、浓度等因素对RA缓蚀性能的影响。实验结果表明,RA分子中的环氧乙烷基的含量不同,缓蚀性能也不一样,其大小顺序为10RA>15RA>5RA,并发现RA与乌洛托品、甲醛、丙炔醇、碘化钾等有很好的协同作用。文中还计算了RA的反应表观活化能,对其缓蚀机理进行了探讨。 相似文献
7.
本文阐述了用软件重用的方法,去开发较通用的物业管理系统,列出了实现重用性所需解决的问题,以及在实际系统中的解决方法,并详细介绍了各个实现细节。本系统是在PC机上用FOXPRO2.6FORWINDOWS开发的。 相似文献
8.
9.
Meng Jun min Ocean University of Qingdao Qingdao China Zhang Zi li Zhao Jun sheng First Institute of Oceanography State Oceanic Administration Qingdao China Zhang Jie Key Laboratory of Marine Science Numerical Modelling 《水动力学研究与进展(B辑)》2001,(3)
1 . INTRODUCTIONOceaninternalwaveisakindofgravitywavegeneratedinthestratifiedocean .Itproducebytheinteractionoftidecurrentandtopography ,seaquakeandmovingshipwhenthestrong ,shallowpycnoclineis present.Theinternalwavesinthecontinentalshelfarealmosttideprod… 相似文献
10.
Autodesk Animator pro(简称Ani pro)是电脑动画应用的二维绘图动画软件。笔者在使用Ani pro进行动画演示制作时,遇到几个问题,通过反复思考实践得以解决,现介绍如下。 相似文献