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3D textured model encryption via 3D Lu chaotic mapping

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Science China(Information Sciences) 2017年第12期60卷 224-232页

作者： Xin JIN Shuyun ZHU Chaoen XIAO Hongbo SUN Xiaodong LI geng ZHAO shiming ge Department of Computer Science and Technology Beijing Electronic Science and Technology Institute School of Telecommunications Engineering Xidian University Department of Electronic Information Engineering Beijing Electronic Science and Technology Institute Institute of Information Engineering Chinese Academy of Sciences

In the emerging Virtual/Augmented Reality(VR/AR) era, three dimensional(3 D) content will be popularized just as images and videos today. The security and privacy of these 3 D contents should be taken into consideration. 3 D contents contain surface models and solid models. Surface models include point clouds,meshes and textured models. Previous work mainly focused on the encryption of solid models, point clouds and meshes. This work focuses on the most complicated 3 D textured model. We propose a 3 D Lu chaotic mapping based encryption method for 3 D textured models. We encrypt the vertices, polygons, and textures of3 D models separately using the 3 D Lu chaotic mapping. Then the encrypted vertices, polygons and textures are composited together to form the final encrypted 3 D textured model. The experimental results reveal that our method can encrypt and decrypt 3 D textured models correctly. Furthermore, typical statistic and brute-force attacks can be resisted by the proposed method.

关键词： 3D model surface model textured model 3D model encryption 3D Lu chaotic mapping

Oxygen reduction electrocatalysis:From conventional to single-atomic platinum-based catalysts for proton exchange membrane fuel cells

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Frontiers in Energy 2024年第2期18卷 206-222页

作者： Cheng YUAN shiming ZHANG Jiujun ZHANG Institute for Sustainable Energy/College of Sciences Shanghai UniversityShanghai 200444China

Platinum(Pt)-based materials are still the most efficient and practical catalysts to drive the sluggish kinetics of cathodic oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs).However,their catalysis and stability performance still need to be further improved in terms of corrosion of both carbon support and Pt catalyst particles as well as Pt loading *** on the developed synthetic strategies of alloying/nanostructuring Pt particles and modifying/innovating supports in developing conventional Pt-based catalysts,Pt single-atom catalysts(Pt SACs)as the recently burgeoning hot materials with a potential to achieve the maximum utilization of Pt are comprehensively reviewed in this *** design thoughts and synthesis of various isolated,alloyed,and nanoparticlecontained Pt SACs are *** single-atomic Pt coordinating with non-metals and alloying with metals as well as the metal-support interactions of Pt single-atoms with carbon/non-carbon supports are emphasized in terms of the ORR activity and stability of the *** advance further research and development of Pt SACs for viable implementation in PEMFCs,various technical challenges and several potential research directions are outlined.

关键词： oxygen reduction electrocatalysis Pt singleatom catalysts conventional Pt-based catalysts design thoughts and synthesis metal-support interactions

Effect of Calcination Temperature on the Microstructure and Surface Properties of a Cu/ZnO Catalyst Derived from Zn_(3)Cu_(2)(OH)_(6)(CO_(3))_(2)

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 46-56页

作者： Qiu shiming Wang Shengjie School of Chemistry and Chemical Engineering Guangxi Minzu Normal UniversityChongzuo 532200GuangxiChina Guangxi Key Laboratory for High-value Utilization of Manganese Resources Chongzuo 532200GuangxiChina

The Cu/ZnO catalyst formed upon the calcination of aurichalcite has a uniform distribution of ZnO,which can delay the sintering of Cu species at high *** this study,aurichalcite possessing a nearly pure phase was prepared using the ammonium complex dissociation precipitation method,and the effect of calcination temperature on the structure and surface properties of the derived Cu/ZnO catalyst was *** results show that the calcination temperature determines the particle size and crystallization degree of the Cu/ZnO catalyst and the surface properties of the corresponding copper oxide and reduced ***-temperature calcination is more conducive to reducing the particle size of the Cu/ZnO catalyst,increasing the specific surface area,and generating abundant defect characteristics on the surface,which is key to obtaining highly dispersed copper and copper-specific surface area catalysts by subsequent ***,the Cu/ZnO catalyst derived using a 300℃or 400℃calcination proved to have a higher specific activity per gram of copper than a commercial Cu/Zn/Al *** discovery in this study opens up a new method for the convenient preparation of a high-temperature resistant Cu/Zn methanol reforming catalyst.

关键词： methanol reforming copper zinc oxide lattice defect

A Fuzzy Trust Management Mechanism with Dynamic Behavior Monitoring for Wireless Sensor Networks

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China Communications 2024年第5期21卷 177-189页

作者： Fu shiming Zhang Ping Shi Xuehong School of Artificial Intelligence Chongqing University of EducationChongqing 400065China School of Communications and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China

Traditional wireless sensor networks(WSNs)are typically deployed in remote and hostile environments for information *** wireless communication methods adopted by sensor nodes may make the network highly vulnerable to various *** encryption and authentication mechanisms cannot prevent attacks launched by internal malicious *** trust-based security mechanism is usually adopted to solve this problem in ***,the behavioral evidence used for trust estimation presents some uncertainties due to the open wireless medium and the inexpensive sensor ***,how to efficiently collect behavioral evidences are rarely *** address these issues,in this paper,we present a trust management mechanism based on fuzzy logic and a cloud ***,a type-II fuzzy logic system is used to preprocess the behavioral evidences and alleviate ***,the cloud model is introduced to estimate the trust values for sensor ***,a dynamic behavior monitoring protocol is proposed to provide a balance between energy conservation and safety *** results demonstrate that our trust management mechanism can effectively protect the network from internal malicious attacks while enhancing the energy efficiency of behavior monitoring.

关键词： behavior monitoring cloud fuzzy trust wireless sensor networks

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论网络环境下的书目情报服务策略

图书馆 2008年第4期 104-105页

作者：葛世民河南省漯河二中图书馆河南漯河462000

网络环境给书目情报带来了新的内容,要满足用户的需求,就必须采用相应的策略来改善书目情报服务。具体来讲,应从加强书目情报服务的硬环境建设、加强网络书目信息资源的建设与开发、提高书目情报服务人员的服务水平和整体素质、寻求合... 详细信息

网络环境给书目情报带来了新的内容,要满足用户的需求,就必须采用相应的策略来改善书目情报服务。具体来讲,应从加强书目情报服务的硬环境建设、加强网络书目信息资源的建设与开发、提高书目情报服务人员的服务水平和整体素质、寻求合作发展四个方面努力。

关键词：网络环境书目情报书目情报服务

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基于梯度场的拼接缝消除方法

计算机辅助设计与图形学学报 2007年第2期19卷 227-232,239页

作者：葛仕明程义民李杰张玲中国科学技术大学电子科学与技术系合肥230027

提出了一种基于图像梯度场的拼接缝消除方法——GFBSE.在一般的整体变分模型中引入源图像的梯度场,建立一个基于梯度场的能量函数,通过求解非线性偏微分方程以优化该能量函数来实现拼接缝消除.该方法能够在全局消除图像拼接中的颜色不一... 详细信息

提出了一种基于图像梯度场的拼接缝消除方法——GFBSE.在一般的整体变分模型中引入源图像的梯度场,建立一个基于梯度场的能量函数,通过求解非线性偏微分方程以优化该能量函数来实现拼接缝消除.该方法能够在全局消除图像拼接中的颜色不一致,同时能够较好地处理由于图像配准造成的几何结构的错位.最后与当前常用的几种方法进行了理论和实验上的讨论和比较,表明了GFBSE方法的有效性.

关键词：梯度场整体变分图像拼接拼接缝消除偏微分方程

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人眼3D肌肉控制模型

计算机辅助设计与图形学学报 2006年第11期18卷 1710-1716页

作者：曾丹程义民葛仕明李杰中国科学技术大学电子科学与技术系合肥230027

根据解剖学原理及人眼运动特征,提出了一种人眼3D肌肉控制模型·该模型由内部模型和外部模型组成,其3D运动由3类共8条肌肉控制·模型建模及驱动比较方便,并已在PC机上进行了模拟·模拟结果表明,人眼模型逼真,可较好地模拟人眼运动及表情·

关键词：人眼3D肌肉控制模型人眼内部模型人眼外部模型

Rethinking attribute localization for zero-shot learning

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Science China(Information Sciences) 2024年第7期67卷 184-196页

作者： Shuhuang CHEN shiming CHEN Guo-Sen XIE Xiangbo SHU Xinge YOU Xuelong LI School of Electronic Information and Communication Huazhong University of Science and Technology School of Computer Science and Engineering Nanjing University of Science and Technology School of Artificial Intelligence Optics and Electronics Northwestern Polytechnical University

Recent advancements in attribute localization have showcased its potential in discovering the intrinsic semantic knowledge for visual feature representations, thereby facilitating significant visual-semantic interactions essential for zero-shot learning(ZSL). However, the majority of existing attribute localization methods heavily rely on classification constraints, resulting in accurate localization of only a few attributes while neglecting the rest important attributes associated with other classes. This limitation hinders the discovery of the intrinsic semantic relationships between attributes and visual features across all *** address this problem, we propose a novel attribute localization refinement(ALR) module designed to enhance the model's ability to accurately localize all attributes. Essentially, we enhance weak discriminant attributes by grouping them and introduce weighted attribute regression to standardize the mapping values of semantic attributes. This module can be flexibly combined with existing attribute localization *** experiments show that when combined with the ALR module, the localization errors in existing methods are corrected, and state-of-the-art classification performance is achieved.

关键词： zero-shot learning attention mechanism attribute localization image classification

An efficient CuZr-based metallic glasses electrode material for electrocatalytic degradation of azo dyes

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Journal of Environmental Sciences 2024年第2期136卷 537-546页

作者： Zhiwang Deng Bowen Zhao Songtao Li Zhengkun Li shiming Zhang Kewei Zhang Zhengwang Zhu Taiyuan University of Science and Technology School of materials science and engineeringTaiyuan 030024China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Chinese Academy of Sciences Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Qingdao Yunlu Advanced Materials Technology Co. Ltd.Qingdao 266232China

Metallic glasses have received a lot of attention on wastewater treatment due to their unique atomic structure,and the use of metallic glasses as electrodes has produced unexpected electrocatalytic degradation effects for many pollutants through combining with electrochemical ***,it still is a formidable challenge to find a metallic glass electrode material with both efficient and clean for the catalytic degradation of *** this work,the Cu_(55)Zr_(45)metallic glassy ribbons are used as an electrode to degrade azo dyes and show the excellent degradation effect,which can reach 95.6%within 40 *** the degradation process,almost no additives are produced and Cu_(55)Zr_(45)metallic glassy ribbons have excellent effects under different pH ***,it exhibits good stability for degradation efficiency during the 8 cycle degradation tests of the amorphous alloy *** the copper nanoparticles are exposed on the surface of the ribbons,the oxidized copper obtained synergistically produce activated radicals is the primary degradation mechanism,where the auxiliary degradation mechanisms include electron transfer and the promotion of active *** research develops a new type of electrode material for wastewater treatment,and the economy and high efficiency of Cu55Zr45metallic glass endow it the expandable functional applications.

关键词： Metallic glasses Azo dyes Electrocatalytic Degradation Oxidized copper