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Journal of Materials Science & Technology 2022年第13期108卷 125-132页

作者： dong huang Yanxin Zhuang Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang110819China

Transformation-induced plasticity(TRIP)endows material with continuous work hardening ability,which is considered as a powerful weapon to break the strength-ductility ***,FCC based alloys with TRIP effect can not get rid of the“soft”feature of the structure entirely,resulting in insufficient yield ***,a Co_(x)Cr_(25)(AlFeNi)_(75-x) high-entropy alloy is *** phase is used as strengthening component to improve yield strength,while TRIP effect ensures *** with the previous TRIP high-entropy alloy,its yield strength is nearly doubled,and the uniform elongation is more than 55%at room ***,the corresponding multiphase microstructure evolution and deformation mechanisms are ***,stacking faults andΣ3 twin boundaries are confirmed to be the nucleation sites of HCP phase by *** composition design and proper heat treatment process make it a perfect combination of precipitation strengthening and transformationinduced plasticity,and thus guide design in the high-performance alloy.

关键词： High-entropy alloys Transformation-induced plasticity Precipitation strengthening Nucleation site HAADF-STEM

Polycyclic aromatic hydrocarbons in surface sediments of the Zhelin Bay in the South China Sea

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Acta Oceanologica Sinica 2007年第2期26卷 123-132页

作者： dong Qiaoxiang huang Hong huang Changjiang School of Environmental Science and Public Health Wenzhou Medical College Wenzhou 325035 China

This study examined the concentrations of polycyclic aromatic hydrocarbons （PAHs） in surface sediments collected in July 2004 from eight stations in the Zhelin Bay, one of the most important bays for large-scale mariculture in Guangdong Province. Thirteen individual parent PAH compounds were identified using high performance liquid chromatography with UV detection. The overall average concentration of total PAHs was 477.0 ng/g, ranging from 146.1 to 928.8 ng/g. Low molecular mass PAHs with two to three rings （e.g., acenaphthene） were dominant in each sample. The PAH concentration varied among sampling stations, with the highest concentration observed at bay outlets and the lowest found at stations outside the bay. Ratios of low to high molecular mass PAHs and fluoranthene to pyrene were used to determine the origin of PAHs, and results indicated mainly petroleum-derived contamination. Compared with other bays and harbors around the world, the total concentrations of PAHs in surface sediments at the Zhelin Bay are moderate, but this does not exclude the possibility of potential impact on human consumers because some strong carcinogenic PAHs with high molecular mass were found at the station with a nearby caged-fish and oyster farm. Long-term monitoring of PAH contamination in the Zhelin Bay is recommended to reduce the potential toxicological effects on aquatic： organisms and humans.

关键词： polycyclic aromatic hydrocarbons (PAHs) surface sediment Zhelin Bay Guangdong China

Transaction Frequency Based Trust for E-Commerce

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Computers, Materials & Continua 2023年第3期74卷 5319-5329页

作者： dong huang Sean Xu School of Applied Foreign Languages Zhejiang Yuexiu UniversityShaoxing312000China Anzina PTY Ltd. SydneyNSW2118Australia

Most traditional trust computing models in E-commerce do not take the transaction frequency among participating entities into consideration,which makes it easy for one party of the transaction to obtain a high trust value in a short time,and brings many disadvantages,uncertainties and even *** solve this problem,a transaction frequency based trust is proposed in this *** proposed method is composed of two *** first part is built on the classic Bayes analysis based trust modelswhich are ease of computing for the E-commerce *** second part is the transaction frequency module which can mitigate the potential insecurity caused by one participating entity gaining trust in a short *** show that the proposed method can effectively mitigate the self-promoting attacks so as to maintain the function of E-commerce system.

关键词： Transaction frequency trust Bayes analysis E-commerce

A New Elaterid from the Middle Jurassic Daohugou Biota(Coleoptera:Elateridae:Protagrypninae)

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Acta Geologica Sinica(English Edition) 2011年第6期85卷 1224-1230页

作者： dong Fabing huang Diying State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

A new genus and species of fossil elaterid namely Clavelater ningchengensis gen. et sp. nov. assigned to the subfamily Protagrypninae based on one specimen from the Middle Jurassic Jiulongshan Formation near Daohugou Village, Ningcheng County, Inner Mongolia, northeastern China is described and illustrated. This specimen displays a pair of large antennae that easily differs from those of most Mesozoic elaterids. There are around 36 species within 20 genera referred to elateroids described from the Early Jurassic to Miocene of China, with another three species within three genera reviewed, but the taxonomic assignment of at least seven species within three genera is doubted. The systematic position of fossil elateriform beetles reported from China is reviewed and the evolution of Mesozoic elateroids briefly discussed.

关键词： taxonomy Insecta Elateroidea Elateridae Protagrypninae Inner Mongolia

Molecular dynamics simulation of alkaline electrolyte diffusion in anion exchange membrane

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Science China(Technological Sciences) 2020年第11期63卷 2241-2255页

作者： SONG BingYe LI dong HE YaLing huang dong TONG ZiXiang Key Laboratory of Thermo-Fluid Science and Engineering of MOE School of Energy&Power EngineeringXi’an Jiaotong UniversityXi’an 710049China

During the operation of alkaline direct liquid fuel cells,the alkaline electrolyte is usually needed in the anode electrode to accelerate the electrochemical reaction kinetics of the liquid ***,the crossover of the alkaline solution in the anode through the anion exchange membrane to the cathode can increase the transfer resistance of the oxygen in the *** order to reduce the crossover of the alkaline solution,the diffusion process of the alkaline solution in the anion exchange membrane needs to be fully *** this work,interface models of anion exchange membrane-alkaline electrolytes are established based on the cell structure of the quaternary ammonium polysulfone(QAPS)membrane to simulate the dynamic process of the alkaline solution in the *** effect of the type and the concentration of the alkaline solution on the transportation of the metal ions and OH^-in the membrane are *** results show that the agglomeration of Na+is formed more easily than K^+in the interface *** of the strong interaction of Na^+on OH^-,OH^-ions appear to be concentrated,resulting in that the diffusion coefficients of the metal ion and OH^-in the in Na^+solution are lower than those in the K^+*** addition,with the raised concentration of electrolyte solution,the aggregation degrees of the metal ions and OH^-can be increased,which means an enlarged mass transfer resistance of the ***,by adding a polytetrafluoroethylene(PTFE)layer on the QAPS membrane,the distribution of metal ions tends to be concentrated,and the number of hydrophilic channels in the QAPS membrane is reduced,which significantly increases the alkali resistance of the anion exchange membrane.

关键词： direct liquid fuel cells anion exchange membrane alkali crossover QAPS membrane

Effect of hot stamping parameters on the mechanical properties and microstructure of cold-rolled 22MnB5 steel strips

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International Journal of Minerals,Metallurgy and Materials 2014年第6期21卷 544-555页

作者： Jing Zhou Bao-yu Wang Ming-dong huang dong Cui School of Mechanical Engineering University of Science and Technology Beijing

Thermomechanical experiments were carried out to reproduce the hot stamping process and to investigate the effects of process parameters on the microstructure and mechanical properties of stamped parts. The process parameters, such as austenitizing temperature, soaking time, initial deformation temperature and cooling rate, are studied. The resulting microstructures of specimens were observed and analyzed. To evaluate the mechanical properties of specimens, tensile and hardness tests were also performed at room temperature. The op-timum parameters to achieve the highest tensile strength and the desired microstructure were acquired by comparing and analyzing the results. It is indicated that hot deformation changes the transformation characteristics of 22MnB5 steel. Austenite deformation promotes the austen-ite-to-ferrite transformation and elevates the critical cooling rate to induce a fully martensitic transformation.

关键词： boron steel strip metal stamping mechanical properties microstructure phase transitions

Mechanical Property, Oxidation and Ablation Resistance of C/C–ZrB_2–ZrC–SiC Composite Fabricated by Polymer Infiltration and Pyrolysis with Preform of C_f/ZrB_2

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Journal of Materials Science & Technology 2017年第5期33卷 481-486页

作者： dong huang Mingyu Zhang Qizhong huang Liping Wang Kai Tong College of Materials Science and Engineering Hunan University State Key Laboratory for Powder Metallurgy Central South University

CJC-ZrB2-ZrC-SiC composites were fabricated by polymer infiltration and pyrolysis （PIP） with a preform of G/ZrB2. The carbon fibers and the resin carbon were coated with ceramic layer after PIP in the com- posites. The composite presents a pseudo-plastic fracture due to deflection of cracks and pullout of fibers. The composite has a higher bending strength by this method in comparison with the conventional PIP process due to fewer heat treatment cycles. The static oxidation test shows that the mass loss of the composites is no more than 1% after 20 rain oxidation at 1100 ~C. The ＂core-shell＂ structure between ZrC-SiC ceramic and other phases plays a positive role in preventing the inward diffusion of oxygen. The ablation resistance of the C/C-ZrB2-ZrC-SiC composite samples was tested using a plasma generator. After ablation for 120 s, the mass and linear ablation rates of the composites are 4.65 mg cm-2 s-1 and 2.46 μm s-1, respectively. The short carbon layer shows a better ablation resistance than the nonwoven carbon fabric layer after the ceramic coating is peeled off because of its higher ceramic content.

关键词： C/C composite Ceramic-matrix composites High temperature corrosion

Elimination of Spatial Side-Channel Information for Compact Quantum Key Distribution Senders

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Journal of Electronic Science and Technology 2019年第3期17卷 195-203页

作者： Wei-Shao huang Wei Zhang Yi-dong huang the Department of Electronic Engineering Tsinghua UniversityBeijing 100084 the Beijing National Research Center for Information Science and Technology the Beijing Innovation Center for Future Chipsand also the Department of Electronic EngineeringTsinghua UniversityBeijing 100084 Frontier Science Center for Quantum Information Beijing 100084 Beijing Academy of Quantum Information Sciences Beijing 100193

For a compact quantum key distribution (QKD) sender for the polarization encoding BB84 protocol, an eavesdropper could take a side-channel attack by measuring the spatial information of photons to infer their polarizations. The possibility of this attack can be reduced by introducing an aperture in the QKD sender, however, the effect of the aperture on the QKD security lacks of quantitative analysis. In this paper, we analyze the mutual information between the actual keys encoded at this QKD sender and the inferred keys at the eavesdropper (Eve), demonstrating the effect of the aperture to eliminate the spatial side-channel information quantitatively. It shows that Eve’s potential on eavesdropping spatial side-channel information is totally dependent on the optical design of the QKD sender, including the source arrangement and the aperture. The height of compact QKD senders with integrated light-emitting diode (LED) arrays could be controlled under several millimeters, showing great potential on applications in portable equipment.

关键词： Diffraction-limited imaging system mutual information quantum key distribution spatial side-channel information

Method for triangular fuzzy multiple attribute decision making based on two-dimensional density operator method

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Journal of Systems Engineering and Electronics 2024年第1期35卷 178-185页

作者： LIN Youliang LI Wu LIU Gang huang dong School of Economics and Management Hunan Institute of Science and TechnologyYueyang 414000China Hunan Vocational College for Nationalities Yueyang 414000China School of Information Science and Engineering Hunan Institute of Science and TechnologyYueyang 414000China

Aiming at the triangular fuzzy(TF)multi-attribute decision making(MADM)problem with a preference for the distribution density of attribute(DDA),a decision making method with TF number two-dimensional density(TFTD)operator is proposed based on the density operator theory for the decision maker(DM).Firstly,a simple TF vector clustering method is proposed,which considers the feature of TF number and the geometric distance of ***,the least deviation sum of squares method is used in the program model to obtain the density weight ***,two TFTD operators are defined,and the MADM method based on the TFTD operator is ***,a numerical example is given to illustrate the superiority of this method,which can not only solve the TF MADM problem with a preference for the DDA but also help the DM make an overall comparison.

关键词： fuzzy decision making clustering density operator multi-attribute decision making(MADM)

Photographic Appearance Enhancement via Detail-Based Dictionary Learning

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Journal of Computer Science & Technology 2017年第3期32卷 417-429页

作者： Zhi-Feng Xie Shi Tang dong-Jin huang You-dong Ding Li-Zhuang Ma Department of Film and Television Engineering Shanghai University Shanghai 200072 China Shanghai Engineering Research Center of Motion Picture Special Effects Shanghai 200072 China Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

A number of edge-aware filters can efficiently boost the appearance of an image by detail decomposition and enhancement. However, they often fail to produce photographic enhanced appearance due to some visible artifacts, especially noise, halos and unnatural contrast. The essential reason is that the guidance and the constraint of high-quality appearance are not sufficient enough in the process of enhancement. Thus our idea is to train a detail dictionary from a lot of high-quality patches in order to constrain and control the entire appearance enhancement. In this paper, we propose a novel learning-based enhancement method for photographic appearance, which includes two main stages： dictionary training and sparse reconstruction. In the training stage, we construct a training set of detail patches extracted from some high-quality photos, and then train an overcomplete detail dictionary by iteratively minimizing an？1-norm energy function. In the reconstruction stage, we employ the trained dictionary to reconstruct the boosted detail layer, and further formalize a gradient-guided optimization function to improve the local coherence between patches. Moreover, we propose two evaluation metrics to measure the performance of appearance enhancement. The final experimental results have demonstrated the effectiveness of our learning-based enhancement method.

关键词： image enhancement dictionary learning edge-aware filter