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Security Issues and Defensive Approaches in Deep Learning Frameworks

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Tsinghua science and Technology 2021年第6期26卷 894-905页

作者： Hongsong Chen Yongpeng Zhang Yongrui Cao Jing Xie Department of Computer science University of Science and Technology Beijing(USTB)Beijing 100083China Beijing Key Laboratory of Knowledge Engineering for Materials science Beijing 100083China Department of Computer science and Technology University of Science and Technology Beijing(USTB)Beijing 100083China Defense Electronics Institute China Industrial Control System Cyber Emergency Response TeamBeijing 100040China

Deep learning frameworks promote the development of artificial intelligence and demonstrate considerable potential in numerous ***,the security issues of deep learning frameworks are among the main risks preventing the wide application of *** on deep learning frameworks by malicious internal or external attackers would exert substantial effects on society and *** start with a description of the framework of deep learning algorithms and a detailed analysis of attacks and vulnerabilities in *** propose a highly comprehensive classification approach for security issues and defensive approaches in deep learning frameworks and connect different attacks to corresponding defensive ***,we analyze a case of the physical-world use of deep learning security *** addition,we discuss future directions and open issues in deep learning *** hope that our research will inspire future developments and draw attention from academic and industrial domains to the security of deep learning frameworks.

关键词： adversarial examples deep learning frameworks defensive approaches security issues

Effect of minor aluminium addition in Cu47Ti34Zr11Ni8 bulk metallic glasses

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中国有色金属学会会刊：英文版 2005年第S3期15卷 176-180页

作者：孔见熊党生叶治淘 Department of Materials science and Engineering Nanjing University of Science and Technology Nanjing 210094 China

Cu47Ti34Zr11Ni8 and (Cu47Ti34Zr11Ni8)_ 99Al bulk metallic glass with size of 1mm×10mm×50mm were prepared by copper mold casting, and the influence of minor aluminium addition upon the alloy thermal stability and mechanical properties was studied. The results indicate that with the aluminium addition, the crystallizing behavior of the melt changes at the same cooling rate, and the crystallizing behavior of the glass changes at the same heating rate. The glass transition temperature(T_g), crystallization temperature(T_ x1), temperature interval of supercooled liquid region ΔT_x (=T_ x1-T_g) and reduced glass transition temperature (T_ rg) are proved to be changed from 672K, 734K, 62K and 0.578 to 681K, 729K, 48K and 0.590, respectively. Because of the addition of aluminium, three point-bending flexural strength and flexural modulus of the bulk glass are increased from 2350MPa and 102GPa to 2970MPa and 108GPa, respectively.

关键词： bulk metallic glass(BMG) copper-titanium-zirconium-nickel alloy glass-forming ability(GFA) thermal stability mechanical property

Preparation of SiC_p/Al_2O_3-Al Composites by Directed Metal Oxidation

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Chinese Journal of Aeronautics 2006年第B12期19卷 47-50页

作者： LIN Ying YANG Hai-bo WANG Fen ZHU Jian-feng School of Materials science and Engineering Shaanxi University of Science ＆ Technology Xianyang 712081 China

SiCp/Al2O3-Al composites were synthesized by means of direct metal oxidation method. The composition and microstructures of the composites were investigated using X-ray diffraction （XRD）, scanning electron microscopy （SEM） and metallurgical microscope. The effects of technical parameters on the properties of the product were analyzed. The results indicate that the composite possesses a dense microstructure, composed of three interpenetrated phases. Of them, SiO2 layer prohibits the powdering of the composites; Mg promotes the wetting and infiltration of the system and Si restricts the interfacial reaction while improving the wetting ability between reinforcement and matrix.

关键词： SiCD/Al2O3-Al composites: directed metal oxidation Al-Mg-Si alloy SiC reinforcement

Nano-scaled metal powder improving tribological properties of lubricant

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中国有色金属学会会刊：英文版 2005年第S3期15卷 167-170页

作者：万轶熊党生王恒志 Department of Materials science and Engineering Nanjing University of Science and Technology Nanjing 210094 China

Cu nanoparticles were fabricated by ball milling with the anhydrous alcohol as dispersant. The size and figure of Cu nanoparticles were characterized by X-ray diffractometry and transmission electron microscopy. The tribological properties of adding Cu and MoS2 nanoparticles to the pure grease were measured on MM-200 tester, compared with the single additive and pure grease. The results show the size of Cu nanoparticles is about 50 nm. The surface with lubricant added nanopowder as additive possesses a remarkable decrease in wear volume. The friction coefficient and wear volume of lubricant mixed with 5% copper and 30% disulfide molybdenum nanoparticles are 0.09 and 1.80mm3, respectively. This mixed additive can not only increase the ability of supporting heavy load but repair the microscopic channels and cracks on the wear surface. Under higher load and long period of time, this lubricant has the characteristics of self-repairing, occluding resistance and ability of enduring higher temperature.

关键词： nano-scaled metal powder ball milling friction and wear properties

Lathe process of AZ91D magnesium alloy chips used in semi-solid thixomolding

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中国有色金属学会会刊：英文版 2005年第S3期15卷 236-240页

作者：吉泽升洪艳赵密 College of Materials science and Engineering Harbin University of Science and Technology Harbin 150040 China

Based on the mechanism of chip breaking and the principle of semi-solid thixomolding, the lathe process of AZ91D magnesium alloys chips used in semi-solid thixotropic injection molding process was studied. With three kinds of turning tools, such as 31303C5, 31003C and 31303C, different chips were gotten. And by one tool with different lathe parameters, different chips were gotten. The results show that, under the needed condition of the thixotropic injection molding machine, the ideal chips are gotten and the size of magnesium alloy chips must be about 35mm, and the turning tool is chosen, whose chip breaker groove is narrower and the depth of cutting is more than 3mm as well as the amount of feed is larger than 0.3mm. The deformation occurs on the microstructure of the chips, and the residual stress is important to the later microstructure of semi-solid state in injection molding.

关键词： magnesium alloy chips semi-solid thixotropic injection lathe process

STUDY ON CATIONIC RING-OPENING COPOLYMERIZATION OF 1,4-ANHYDRO-2,3-DI-O-BENZYL-α-D-RIBOPYRANOSE WITH 1,4-ANHYDRO-2,3-O-ISOPROPYLIDENE-α-D-RIBOPYRANOSE

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Chinese Journal of Polymer science 1997年第3期15卷 282-288页

作者：吴承佩潘才元瓜生敏之 Department of Materials science and Engineering University of Science and Technology of China Hefei 230026 Institute of Industrial science University of Tokyo Roppongi Minato-ku Tokyo 106 Japan

Cationic ring-opening copolymerization of 1, 4-anhydro-2, 3-O-isopropylidene-α-D-ribo-pyranose (AIRP) with 1,4-anhydro-2,3-di-O-benzyl-α-D-ribopyranose (ADBR) preparedfrom D-ribose was studied. Copolymerization using SbCl_5 or BF_3 OEt_2 as catalyst atlow temperature gave stereoregular (1→4)β-D-ribofuranan (C-1 and C-4 ring cleavagesee Scheme 1) or (1→5) α-D-ribofuranan (C-1 and C-5 ring cleavage) respectively. Theeffects of catalysts, reaction time and temperatures on yield and stereoregularity of the ob-tained polymers were studied. Polymers were characterized by molecular weight, ~1HNMR,^(13)CNMR and optical rotation.

关键词： 1,4-Anhydroribose derivatives Cationic ring-opening copolymerization Specific rotation Lewis acid catalysts

Strengthening CoCrFeNi high-entropy alloy by Laves and boride phases

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China Foundry 2022年第6期19卷 457-463页

作者： Xiu-gang Chen Gang Qin Xue-feng Gao Rui-run Chen Qiang Song Hong-zhi Cui School of Materials science and Engineering Shandong University of Science and TechnologyQingdao 266500China School of Materials science and Engineering Harbin Institute of TechnologyHarbin 150001China

To strengthen the face-centered-cubic(FCC)type CoCrFeNi high-entropy alloy(HEA)by in-situ reinforced phase,(CoCrFeNi)_(100-x)(NbB_(2))_(x)(x=0,2,4,6,8,at.%)alloys were *** constitution,microstructure,tensile mechanical properties of the alloys were studied,and the mechanisms were *** show that the microstructure of all the reinforced alloys consists of the matrix FCC phase,Laves phase,and(Cr_(3)Fe)B_(x) *** eutectic structure and(Cr_(3)Fe)B_(x) phases are formed in the interdendritic region,and the eutectic structure is composed of Laves and FCC *** x increases from 0 to 8,i.e.,with increase of Nb and B elements,the volume fraction of Laves and(Cr_(3)Fe)B_(x) phases increases gradually from 0 to 5.84%and 8.3%,*** testing results show that the ultimate strength of the alloys increases gradually from 409 MPa to 658 MPa,while the fracture strain decreases from 75%to 1.6%.Fracture analysis shows that the crack originates from the(Cr_(3)Fe)B_(x) *** CoCrFeNi alloys are mainly strengthened by the second phase(Laves phase and boride phase).

关键词： high-entropy alloy boride eutectic structure mechanical properties

Recovering hidden information in audio by genetic algorithm

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Optoelectronics Letters 2009年第4期5卷 313-316页

作者：陈扬坤程义民谢春辉 Department of Electronic science and Technology University of Science and Technology of China

An audio recovering method of spread-spectrum hidden information is proposed based on genetic *** this method the embedded sequence length is confirmed firstly,then the best estimated sequence with the confirmed length is got by genetic algorithm,finally the confidential message hidden in stego-audio can be *** this approach,the hidden information can be recovered without any information from the *** presented method has been implemented on PC,and the experimental results show that the average recovering correct rate is higher than 90%.

关键词：隐藏信息遗传算法音频恢复方法 med 嵌入式发射机正确率

Quantum classifier with parameterized quantum circuit based on the isolated quantum system

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The Journal of China Universities of Posts and Telecommunications 2022年第4期29卷 21-31页

作者： Shi Jinjing Wang Wenxuan Xiao Zimeng Mu Shuai Li Qin School of Computer science and Engineering Central South UniversityChangsha 410083China School of Computer science and School of Cyberspace science Xiangtan UniversityXiangtan 411301China

It is a critical challenge for quantum machine learning to classify the datasets *** article develops a quantum classifier based on the isolated quantum system(QC-IQS)to classify nonlinear and multidimensional ***,a model of QC-IQS is presented by creating parameterized quantum circuits(PQCs)based on the decomposing of unitary operators with the Hamiltonian in the isolated quantum ***,a parameterized quantum classification algorithm(QCA)is designed to calculate the classification results by updating the loss function until it ***,the experiments on nonlinear random number datasets and Iris datasets are designed to demonstrate that the QC-IQS model can handle and generate accurate classification results on different kinds of *** experimental results reveal that the QC-IQS is adaptive and learnable to handle different types of ***,QC-IQS compensates the issue that the accuracy of previous quantum classifiers declines when dealing with diverse *** promotes the process of novel data processing with quantum machine learning and has the potential for more comprehensive applications in the future.

关键词： quantum classifier quantum classification isolated quantum system parameterized quantum circuit Hamiltonian