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51.
Translating multiple real-world source images to a single prototypical image is a challenging problem. Notably, these source images belong to unseen categories that did not exist during model training. We address this problem by proposing an adaptive adversarial prototype network (AAPN) and enhancing existing one-shot classification techniques. To overcome the limitations that traditional works cannot extract samples from novel categories, our method tends to solve the image translation task of unseen categories through a meta-learner. We train the model in an adversarial learning manner and introduce a style encoder to guide the model with an initial target style. The encoded style latent code enhances the performance of the network with conditional target style images. The AAPN outperforms the state-of-the-art methods in one-shot classification of brand logo dataset and achieves the competitive accuracy in the traffic sign dataset. Additionally, our model improves the visual quality of the reconstructed prototypes in unseen categories. Based on the qualitative and quantitative analysis, the effectiveness of our model for few-shot classification and generation is demonstrated. 相似文献
52.
Lijing Wang Fen Xia Wangshu Xu Guanghua Wang Shuqing Hong Fangwen Cheng Binghui Wu Nanfeng Zheng 《Advanced functional materials》2023,33(26):2215127
As a nontoxic and cost-effective material, copper pastes have attracted great attention in both academia and industry. However, achieving the long-term stability of copper pastes remains challenging due to their susceptibility to oxidation. Therefore, stable copper nanoparticles with a Cu(0)–Cu(I) core–shell structure containing a surface passivation layer of formate ions-involved Cu(I) coordination polymers are developed. Based on the self-reducing nature of the passivation layer, the nanoparticle-based copper pastes can be sintered in <1 min, showing high electrical conductivity (220 000 S cm−1), mechanical flexibility, and long-term stability after sintering. The excellent properties of the developed copper pastes are even comparable with the ones of silver pastes. These stable copper pastes have broad applications in printed electronics (e.g., glucose sensors, RFID tags, and electromagnetic shielding films), showing great potential in the fabrication of flexible printed electronics. 相似文献
53.
针对人脸图像试戴3D眼镜过程中存在的镜腿遮挡人脸问题,文中提出一种基于人脸图像的3D眼镜虚拟试戴技术。利用构建的人脸形状的三维模型,使其在虚拟试戴中对镜腿起到消隐作用,解决镜腿的遮挡问题。文中对输入的人脸图像进行关键点检测,结合Graham扫描法求得人脸形状的凸多边形,利用平移扫描构建人脸形状的三维模型。此外,文中根据定位人脸图像上的关键点以及姿态估计后对三维眼镜模型的变换,将眼镜模型佩戴到人脸图像上。实验结果表明,该方法对于多视角的人脸图像实现了虚拟试戴效果,解决了多种视角下人脸图像试戴过程中镜腿的遮挡问题,虚拟试戴中镜腿遮挡平均准确率为94.5%,遮挡精度较高。 相似文献
54.
针对航空机载软件测试环境与开发环境冲突、测试环境可控性和通用性差、非干预性测试困难的问题,分析了全物理实装测试环境、半实物仿真测试环境的优缺点,研究了全数字仿真测试技术,设计并实现了一种航空机载软件全数字仿真测试系统。该系统由仿真核心平台、仿真工具组件、协同仿真组件和人机交互组件构成,提供了航空机载处理器、内存、外设等多种可重用库。提出了基于底层虚拟机的动态二进制翻译技术、协同仿真时间同步和数据通信机制等关键技术,实现了航空机载软件全数字高速闭环仿真运行。工程实践证明,该系统能达到降低硬件设备的依耐性、简化测试环境搭建的复杂度、提高测试效率约42%的目的。 相似文献
55.
Shao Hua SHI Li Jian LIU 《中国化学快报》2006,17(3):361-364
Poly(N-isopropylacrylamide) (PNIPAM) hydrogel, which is insoluble but shrinkable or swellable in aqueous media when temperature rises or drops across 33oC1,2, has been extensively studied due to its potential applications in the fields of controlled drug … 相似文献
56.
G. Rytwo R. Huterer-Harari S. Dultz Y. Gonen 《Journal of Thermal Analysis and Calorimetry》2006,84(1):225-231
Adsorption
of erythrosin-B (EB) and fast green (FG) to a non-charged organosmectite based
on crystal violet adsorbed up to 100% of the cation exchange capacity (CEC)
was tested. Adsorption isotherms of EB and FG were prepared at 3, 24 and 50°C.
All isotherms are of H-type reaching loads of approximately up to 20% of the
original CEC of the crude montmorillonite (up to 0.15 and 0.10 mol dye kg–1
clay for EB and FG, respectively). Adsorption decreases with temperature,
indicating an exothermic process. Enthalpy was evaluated using van’t
Hoff equation, yielding approximately –20 kJ mol–1
for both dyes. 相似文献
57.
58.
Pérez Pavón JL Guerrero Peña A García Pinto C Moreno Cordero B 《Journal of chromatography. A》2004,1047(1):101-109
The direct coupling of a headspace sampler with a mass spectrometer is proposed as a screening tool for the rapid detection of soil pollution by hydrocarbons from petroleum and derivatives. The samples are subjected to the headspace generation process, with no prior treatment, and the volatiles generated are introduced directly into the mass spectrometer, thereby obtaining a fingerprint of the sample analysed. Suitable treatment of the signal by chemometric techniques allows unequivocal characterisation of the different types of sample. The use of fast gas chromatography with a mass spectrometer detector coupled to the headspace sampler allows identification of the major hydrocarbons present in the mineral and organic polluted samples, interpretation of the results obtained, and demonstrates the analytical potential of headspace-mass spectrometry coupling. 相似文献
59.
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