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1.
CRAFT is a tweakable block cipher introduced in 2019 that aims to provide strong protection against differential fault analysis. In this paper, we show that CRAFT is vulnerable to side-channel cube attacks. We apply side-channel cube attacks to CRAFT with the Hamming weight leakage assumption. We found that the first half of the secret key can be recovered from the Hamming weight leakage after the first round. Next, using the recovered key bits, we continue our attack to recover the second half of the secret key. We show that the set of equations that are solvable varies depending on the value of the key bits. Our result shows that 99.90% of the key space can be fully recovered within a practical time.  相似文献   
2.
Inpainting has been continuously studied in the field of computer vision. As artificial intelligence technology developed, deep learning technology was introduced in inpainting research, helping to improve performance. Currently, the input target of an inpainting algorithm using deep learning has been studied from a single image to a video. However, deep learning-based inpainting technology for panoramic images has not been actively studied. We propose a 360-degree panoramic image inpainting method using generative adversarial networks (GANs). The proposed network inputs a 360-degree equirectangular format panoramic image converts it into a cube map format, which has relatively little distortion and uses it as a training network. Since the cube map format is used, the correlation of the six sides of the cube map should be considered. Therefore, all faces of the cube map are used as input for the whole discriminative network, and each face of the cube map is used as input for the slice discriminative network to determine the authenticity of the generated image. The proposed network performed qualitatively better than existing single-image inpainting algorithms and baseline algorithms.  相似文献   
3.
北京奥运国家游泳中心结构初步设计简介   总被引:21,自引:4,他引:21  
中标的北京奥运国家游泳中心成功创造性地采用了由气泡理论衍生的新颖合理的多面体空间刚架结构。本文介绍了这一新型多面体空间刚架结构的构成、性能及其有待深化研究的主要课题。同时简要介绍了该工程整体结构体系的构成、计算分析、基础、ETFE充气枕、钢结构抗火设计、施工方法等有关内容。  相似文献   
4.
针对马店地区断裂发育、构造破碎的特点,在高精度三维地震勘探过程中,运用基于正演模型的参数论证、采用小面元宽方位观测,通过精细表层结构调查、逐点设计井深与优选激发岩性等采集技术,改善了地震资料的单炮品质;在处理上采用静校正、叠前去噪、精细速度建模及叠前深度偏移技术提高复杂断裂带地震资料的成像精度;解释方面采用了三维可视化和相干数据体联合手段,通过精细成图,搞清了马店地区复杂断块圈闭,通过钻探发现了新的含油断块。  相似文献   
5.
采用压延辅助双轴织构技术制备了涂层导体用Ni7W/Ni12W/Ni7W复合基带。复合基带轧制形变过程加入3次不同温度的轧制中间热处理优化其形变组织。采用X射线衍射及背散射电子衍射技术分析了复合基带轧制过程中表面及截面的形变及回复组织,以此探索轧制中间热处理温度对Ni7W/Ni12W/Ni7W复合基带形变及立方织构形成过程的影响机制。结果显示,经600S°C/60Smin轧制中间热处理后的复合基带在较低的再结晶温度下获得了95% (<10°)的高立方织构含量。晶体取向分布图表明该中间热处理温度下复合基带回复及初始再结晶组织中立方取向的晶粒含量都更高;不同取向间点对点的晶体取向差分析证实了立方取向晶粒较大的晶界角,这使立方取向在回复及初始再结晶过程具有高的界面迁移率,从而促进了后续再结晶过程强立方织构的形成。  相似文献   
6.
Electrochemical water-splitting is widely regarded as one of the essential strategies to produce hydrogen energy, while Metal-organic frameworks (MOFs) materials are used to prepare electrochemical catalysts because of its controllable morphology and low cost. Herein, a series of trimetallic porous Pt-inlaid Ni–Fe nanocubes (NCs) are developed with bifunctions of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). In the process of prepare the electrochemical catalysts, Pt nanoparticles are uniformly embedded in the Fe–Ni PBA cube structure, and ascorbic acid is employed as a reducing agent to reduce Pt2+ to Pt nanoparticles. In this work, the cubic structure of Fe–Ni PBA is maintained and the noble metal Pt nanoparticles are embedded. Remarkably, the formation of PBA cubes, Pt inlay and reduction are completed in one step, and Pt nanoparticles are embedded by a simple method for the first time. By employing acid etching method, a porous structure is formed on the PBA cube, which increases the exposed area of the catalyst and provides more active sites for HER and OER. Due to the porous structure, highly electrochemical active surface area and the embedded of highly dispersed Pt nanoparticles, the porous 0.6 Ni–Fe–Pt nanocubes (NCs) exhibits excellently electrocatalytic performance and durable stability to HER and OER. In this work, for HER and OER, the Tafel slopes are 81 and 65 mV dec−1, the overpotential η at the current density of 10 mA cm−2 are 463 and 333 mV, and the onset potential are 0.444 and 1.548 V, respectively. And after a 12-h i-t test and 1000 cycles of cyclic voltammetry (CV), it maintained high stability and durability. This work opens up a new preparation method for noble metal embedded MOF materials and provided a new idea for the preparation of carbon nanocomposites based on MOF.  相似文献   
7.
The laser tracker has been used as the mainstream instrument for the position accuracy calibration of industrial robots for quite a long time. However, due to the complexity of the built-in dual-axis active servo tracking system, its cost is high and the target reflector has to adjust its pose frequently, so it cannot be popularized in the production and application sites of industrial robots. Based on this drawback, a 3D passive laser tracker (3DPLT) with high precision, simple structure, easy operation and low cost is proposed in this paper. Firstly, the overall structure of the system is designed, and its position error model based on the principle of spherical coordinate measurement and vector transfer method is established. Then, the error parameters are identified by experiments to formulate the error compensation model. Finally, the multi-pose and large-range spatial error compensation verification experiments of the system are carried out on a commercial coordinate measuring machine. The results show that the spatial volumetric errors of the 3DPLT can achieve within 40 μm after compensation with a good repeatability of ±4 μm. A comparison contouring test with a commercial ballbar is also carried out to validate its applicability of robot calibration.  相似文献   
8.
In our research, the preparation processes of Pd nanoparticles (Pd NPs) with different methods by adding a certain amount of silver nitrate, iron chloride or sodium iodide are presented in order to control their size and morphology. Various sizes and shapes of Pd NPs are observed by alcohol reduction. The results show the size and morphology control of Pd NPs with chemical reductions of Pd salts by ethanol and ethylene glycol (EG) that have very different reduction processes. The modified polyol method with the gradual addition of Pd and polyvinylpyrollidone precursors in EG at 160°C has led to control their size and morphology in the 10?nm range using 0.02?M AgNO3. It is observed that the Pd nanorod is also formed. The main factors that will control the shapes of Pd NPs have been presented to explain their growth and formation mechanisms in a control process.  相似文献   
9.
In nighttime driving brake lights are particularly important because they offer a warning signal to prevent potential collisions. In this work, we propose a novel visual-based approach for nighttime brake light detection using three-dimensional Nakagami imaging to analyze tail lights of vehicles in front. Rather than heuristic features, such as symmetry of taillights and appearance of the third brake light, the proposed approach extracts invariant features by modeling the scattering of brake lights, thus allowing detection to proceed in a part-based manner. Experiments from extensive datasets show that the proposed system can effectively detect vehicle braking under different lighting and traffic conditions, making it a realistic option for real-world applications.  相似文献   
10.
导航卫星激光后向反射器研究   总被引:1,自引:1,他引:0       下载免费PDF全文
鉴于设计Galileo导航卫星上激光后向反射器的需要,采用理论计算和实验验证的方法对角反射器的光行差补偿设计和远场衍射光强分布进行了研究.对不同直角偏差、是否镀反射膜的角反射器远场衍射光强分布给出了计算和试验结果.研究结果表明:理论计算与实验结果是完全一致的;对类似Galileo卫星的角反射器设计采用光行差角补偿是必要...  相似文献   
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