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1.
Recent generative adversarial networks (GANs) have yielded remarkable performance in face image synthesis. GAN inversion embeds an image into the latent space of a pretrained generator, enabling it to be used for real face manipulation. However, current inversion approaches for real faces suffer the dilemma of initialization collapse and identity loss. In this paper, we propose a hierarchical GAN inversion for real faces with identity preservation based on mutual information maximization. We first use a facial domain guaranteed initialization to avoid the initialization collapse. Furthermore, we prove that maximizing the mutual information between inverted faces and their identities is equivalent to minimizing the distance between identity features from inverted and original faces. Optimization for real face inversion with identity preservation is implemented on this mutual information-maximizing constraint. Extensive experimental results show that our approach outperforms state-of-the-art solutions for inverting and editing real faces, particularly in terms of face identity preservation.  相似文献   
2.
《Ceramics International》2022,48(3):3495-3503
The photochromic phenomenon has been recently used as a fascinating technology in the development of highly efficient anti-counterfeiting materials with dual-mode security encoding of concurrent photochromism and fluorescence emission. Herein, we successfully developed lanthanide-doped aluminate nanoparticles (LAN)/polystyrene (PS) electrospun nanofibers as novel secure authentication films. Different ratios of lanthanide-doped aluminate nanoparticles were mixed with polystyrene-based copolymer solutions in N,N-dimethylformamide (DMF) and subjected to electrospinning to afford photochromic and fluorescent nanofibers. The generated electrospun nanofibers demonstrated a narrow diameter distribution, a smooth surface and well-defined morphological properties. The produced smart nanofibers were applied onto cellulose paper sheets to demonstrate a dual-mode secure strategy with a simple and rapid authentication. LAN was prepared in the nano-scale for better dispersion in PS, which guarantee the formation of transparent films. LAN was studied by transmission electron microscope (TEM) and X-ray diffraction (XRD). LAN displayed diameters of 5–12 nm. On the other hand, the fibrous diameters of LAN-PS samples were studied by scanning electron microscopy (SEM) to indicate diameters of 200–300 nm. The induced security marking was invisible (363 nm) under visible daylight turning into visible green (520 nm) color under ultraviolet irradiation demonstrating a bathochromic shift. Both excitation and emission displayed high intensities. The security marking was fully reversible under ultraviolet/visible irradiation cycles without fatigue. Those advantageous properties could be attributed to the high surface area of the chromogenic nanofibrous films to result in high absorption of light leading to strong optical dual-mode photo-responsiveness. The generated LAN-PS hybrid films showed improved hydrophobic properties with increasing LAN. The nanofibers showed transparency, stretchability and flexibility. The present strategy can be reported as an efficient technology to develop many anti-counterfeiting products toward a better market with social and economic values to avoid fake products.  相似文献   
3.
对于我国民族传统体育文化空间、记忆叙事的建构与形塑,本研究认为我国民族传统体育文化形成是基于精神信仰与图腾崇拜之上的“仪式性”身体活动。仪式性身体活动所形成的精神信仰为我国民族传统体育文化的形成、发展与传承提供了文化意识与制度规范上的一种族群记忆;同时又在这种文化传承中塑造了族群性格,构成了族群身份认同的内核,为族群得以稳定、延续,提供了智慧源泉与精神动力。  相似文献   
4.
无线体域网中传输的是与生命高度相关的敏感数据,身份认证是信息安全保护的第一道防线。现有的基于人体生物信息的身份认证方案存在信息难提取、偶然性大和误差性大的问题,基于传统密码学的认证方案需较大计算资源和能量消耗,并不适用于无线体域网环境。为此,在动态口令和非对称加密机制基础上,提出一种适用于无线体域网的动态口令双向认证轻量协议,并对其进行形式化分析。通过理论证明、SVO逻辑推理及SPIN模型检测得出:该协议满足双向认证,且能够抵御重放攻击、伪装攻击、拒绝服务器攻击和口令离线攻击,具有较高安全性。  相似文献   
5.
For the contradiction between high energy consumption of WSN privacy protection algorithm and constrained resources of sensor network,a recoverable data fusion protocol that ensures data integrity and confidentiality based on reversible digital watermarking and homomorphic encryption technology was proposed.On the one hand,the data from the sensor was embedded by the difference expansion method by using the reversible digital watermarking technique,and original data could be recovered by using a reversible watermark to ensure the integrity check of the fusion data when the fusion data were destroyed.On the other hand,elliptic curve homomorphic encryption encrypted data to prevent sensor data from being perceived during data transmission.Security results show that the proposed protocol performs well against cluster head node compromise as well as tampering from an attack.Performance analysis shows that the protocol has significant advantages over other algorithms in terms of computation,communication overhead and propagation delay.The experimental results show that the protocol has a low resource overhead and improves network performance.  相似文献   
6.
移动RFID系统中,读写器与后台数据库之间不再通过有线方式通信,而采用无线方式通信,但也存在一定的安全隐患问题。为确保通信数据的安全,提出一种基于伪随机函数的移动RFID双向认证协议。协议确保标签、读写器、后台数据库三方均进行认证,从而保障通信的安全性;采用字合成等位运算,在一定程度上能够减少总的计算量;三方认证,使得移动RFID系统具备更为广泛的运用价值。安全性及性能分析表明,所提协议具有较高的安全性及较低的成本。  相似文献   
7.
In the last decade, the number of web‐based applications is increasing rapidly, which leads to high demand for user authentication protocol for multiserver environment. Many user‐authentication protocols have been proposed for different applications. Unfortunately, most of them either have some security weaknesses or suffer from unsatisfactory performance. Recently, Ali and Pal proposed a three‐factor user‐authentication protocol for multiserver environment. They claimed that their protocol can provide mutual authentication and is secure against many kinds of attacks. However, we find that Ali and Pal's protocol cannot provide user anonymity and is vulnerable to 4 kinds of attacks. To enhance security, we propose a new user‐authentication protocol for multiserver environment. Then, we provide a formal security analysis and a security discussion, which indicate our protocol is provably secure and can withstand various attacks. Besides, we present a performance analysis to show that our protocol is efficient and practical for real industrial environment.  相似文献   
8.
电表数据经数据采集器采集、数据聚合器收集后传输给数据存储中心,而当前的用电数据采集方法存在数据泄露、中间人攻击,且攻击者不易被发现等风险。针对这一系列问题,提出了RAHRM的方法,采用RSA-AES-HASH签名认证,并采用RSA对智能电表传输的数据进行加密,同时对服务器端进行流量监控和异常报警,为电表数据传输提供一个安全、可靠的通道。实验结果表明,此电表数据采集方法可以降低智能电表通信中的中间人攻击与攻击者不易被发现的风险,保证通信线路的安全。  相似文献   
9.
刘冬  陈晶  杜瑞颖  何琨 《电子学报》2018,46(5):1056-1061
针对传统双因素认证缺乏可用性的问题,本文提出了一种基于情景感知的低交互移动双因素认证系统.用户通过本系统登录网站时,除输入用户名和口令外,只需点击令牌程序的认证键即可完成认证,平均登录时间不超过5秒.同其它可用性加强的移动双因素认证系统相比,本系统能够抵抗同一环境下的攻击者,而且支持用户手机浏览器进行网站登录.最终安全分析和实验结果证实了本方法的有效性.  相似文献   
10.
With the increasing global demand for satellite communications,the problem of entity authentication and access control of the satellite communication network needs to be solved urgently.To solve this problem,a new multiple center-based entity authentication and cross-domain access control scheme was proposed.The scheme divided the multiple centers into two layers for entity authentication,and maped the authorization of the multiple domains to achieve access control.Simulation experiments show that the proposed scheme support the entity authentication for 100 million users.Furthermore,it also allows 1 million users to access in parallel.  相似文献   
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