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Identity-based strong designate verifier signature over lattices

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The Journal of China Universities of Posts and Telecommunications 2014年第6期21卷 52-60页

作者： wang feng-he HU Yu-pu wang Chun-xiao Department of the Mathematics and Physics Shandong Jianzhu University State Key Laboratory of Integrate Services Networks Xidian University

The notion of the identity-based（id-based） strong designate verifier signature（SDVS） was extent to the lattice-based cryptography. The authors proposed an id-based SDVS scheme over lattices by using the basis delegation technical in fixed dimension. The proposed scheme is based on the hardness of the learning with errors（LWE） problem, and the unforgeability against adaptive chosen message and selective identity attack is based on the hardness of the short integer solution（SIS） problem in the random oracle model. If the parameters m, n and q are the same, the signature length of this scheme is only 3mlbq bits shorter than（3m＋n） lb q bits which is the signature length of the known lattice-based SDVS scheme in the public key environment. As a result, the proposed scheme is not only id-based but also efficient about the signature length and the computation cost. Moreover, this article also proposed an id-based strong designate verifier ring signature（SDVRS） scheme based on the proposed SDVS scheme, which satisfies anonimity, unforgeability.

关键词： SDVS lattice-based cryptography id-based cryptography Gaussian sample SIS problem LWE problem

Microstructure and Wear Resistance of N-Doped TiO_2 Coatings Grown on Stainless Steel by Plasma Surface Alloying Technology

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Journal of Iron and Steel Research International 2011年第7期18卷 73-78页

作者： wang he-feng TANG Bin LI Xiu-yan Surface Engineering Institute Taiyuan University of Technology Taiyuan 030024 Shanxi China

N doped TiO2 （N-TiO2） coatings were obtained by oxidation of titanium nitride coatings, which were pre pared by the plasma surface alloying technique on stainless steel （SS）. The microstructure of N-TiO2 coatings was characterized by X-ray diffraction （XRD）, glow discharge optical emission spectrometry （GDOES）, X-ray photoelectron spectroscopy （XPS） and scanning electron microscopy （SEM）, respectively. Ball-on-disc sliding wear was applied to test and compare the tribological behaviors of the coatings and substrate. XRD patterns showed that anatase type TiO2 existed in the coatings after oxidation. GDOES showed that the resultant coatings had a layered structure, comprising of N-TiO2 layer at the top and a diffusion-type interface. Such a hybrid coatings system showed good adhesion with the substrate. According to XPS, residual N atoms partially occupied O atom sites in the TiO2 lattice. Uniform, continuous and compact coatings were observed by SEM images of coatings after oxidation. Under a load of 7.6 N, the coefficient of friction was in the range of 0.27--0.38 for the N-TiO2/Al2O3 systems and the wear rate of the coatings was only one-fourteenth of that for untreated 316L SS. N-TiO2 coatings displayed much better wear resistance and antifrietion performance than SS substrate.

关键词： plasma surface alloying technique wear resistance stainless steel titanium dioxide

Synthesis and Characterization of Amphiphific Block Copolymer Containing PVP and Poly（5-benzyloxytrimethylene carbonate）

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Chinese Chemical Letters 2006年第2期17卷 239-242页

作者： Ying Xia wang feng he Ren Xi ZHUO Key Laboratory of Biomedical Polymers of Ministry of Education Department of Chemistry Wuhan University Wuhan 430072

Amphiphilic copolymer of 5-benzyloxytrimethylene carbonate （BTMC） with poly （vinyl pyrrolidone）（PVP） was successfully synthesized using immobilized porcine pancreas lipase （IPPL） or SnOct2 as catalyst. Hydroxyl terminated PVP, synthesized with 2-mercaptoethanol as a chain transfer reagent, was employed as a rnacroinitiator. The resulting copolymers were characterized by GPC, ^1H NMR and IR. Increasing the BTMC/PVP-OH feed ratio （[B]/[P]） resulted in the increase of Mn of corresponding copolymers and the decrease of Mw/Mn. Immobilized enzyme has comparable catalytic activity to SnOct2 for the copolymerization.

关键词： Amphiphilic copolymer end-functionalized PVP 5-benzyloxytrimethylene carbonate,immobilized enzyme ring-opening polymerization macroinitiator.

Tetra-armed conjugated microporous polymers for gas adsorption and photocatalytic hydrogen evolution

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Science China Chemistry 2017年第8期60卷 1075-1083页

作者： Yunfeng Xu Chong Zhang Pan Mu Na Mao Xue wang Qian he feng wang Jia-Xing Jiang Key Laboratory for Green Chemical Process of Ministry of Education Wuhan Institute of Technology Wuhan 430073 China

Two novel tetra-armed conjugated microporous polymers with different geometries have been designed and synthesized via Suzuki-Miyaura cross coupling polycondensation. Both polymers are stable in various organic solvents tested and are thermally stable. The pyrene-containing polymer of PrPy with the rigid pyrene unit shows a higher Brunauer-Emmet-Teller specific surface area of 1219m2g-1 than the tetraphenylethylene-containing polymer of PrTPE （770m2g 1）, which leads to a high CO2 uptake ability of 3.89mmolg I at 1.13bar/273K and a H2 uptake ability of 1.69wt% at 1.13bar/77K. The photocatalytic hydrogen production experiments revealed that PrPy also shows a better photocatalytic performance than PrTPE due to the higher conjugation degree and planar structure, the broader UV-visible （UV-Vis） absorption, the lower photoluminescence lifetime, and the higher specific surface area.

关键词： perylene conjugated mieroporous polymers gas adsorption hydrogen evolution

Enzymatic Synthesis and Characterization of Novel Polycarbonates Derived from 5-Allyloxy-1, 3-dioxan-2-one and 5, 5-Dimethvl-1.3-dioxan-2-one

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Chinese Chemical Letters 2006年第10期17卷 1385-1387页

作者： Yan Ping wang feng he Gang LIU Ren Xi ZHUO Key Laboratory of Biomedical Polymers of Ministry of Education Department of Chemistry Wuhan University Wuhan 430072

Novel polycarbonates from 5-allyloxy-1, 3-dioxan-2-one （ATMC） with 5, 5-dimethyl- 1, 3-dioxan-2-one （DTC） were successfully synthesized for the first time using immobilized porcine pancreas lipase （IPPL） as catalyst. The resulting copolymers were characterized by IR, ^1H NMR, ^13C NMR and GPC. The molecular weight （Mn） of the copolymer with molar feed ratio of 10：90 （ATMC：DTC） was 9300 and the polydispersity was 1.31, while the Mn increased to 14300 and polydispersity of 1.25 with the feed ratio of 50：50. Moreover, the composition of the copolymers agreed well with the monomer feed.

关键词： 5-Allyloxy-1 3-dioxan-2-one 5 5-dimethyl-1 3-dioxan-2-one enzyme-catalyzed ring opening polymerization polycarbonates.

京津冀地区kNDVI时空变化及对气候因子的响应

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西南农业学报 2024年第8期37卷 1837-1849页

作者：郭岚瑄王贺封沈石凯赵金山魏凯濠河北工程大学矿业与测绘工程学院河北邯郸056038 河北省煤田地质局水文地质队河北邯郸056000

【目的】探究京津冀地区植被动态变化对气候的响应机制,为更好地理解植被变化成因,为指导京津冀地区生态环境修复提供科学依据。【方法】利用趋势分析、偏相关分析、机器学习与可解释性方法,分析2000—2020年京津冀地区核归一化差异植... 详细信息

【目的】探究京津冀地区植被动态变化对气候的响应机制,为更好地理解植被变化成因,为指导京津冀地区生态环境修复提供科学依据。【方法】利用趋势分析、偏相关分析、机器学习与可解释性方法,分析2000—2020年京津冀地区核归一化差异植被指数(kNDVI)的时空变化,探讨京津冀地区及不同用地类型kNDVI对降水和气温响应的差异性。【结果】京津冀地区kNDVI呈改善态势,增速为0.025/10 a,西北部改善较明显,林地明显改善面积最多,约占总面积17%;草地kNDVI的增速最快,为0.061/10 a;东南部城市周边退化明显,耕地kNDVI变化频繁,改善较多;京津冀大部分区域kNDVI与气温和降水的相关性均呈正相关,仅在南部城市周边表现为负相关;降水多年SHAP值为0.028,气温的多年SHAP值为0.016,均对京津冀地区kNDVI产生正面影响,总体上,降水对kNDVI的影响强于气温的影响。京津冀地区kNDVI对气候的响应存在区域差异,东南部平原区域的耕地kNDVI及西北部山区林地、草地kNDVI受降水的促进作用较明显,在城市周边和张家口等植被稀疏区域kNDVI受降水负面影响;气温对西北部林地与草地kNDVI的促进作用强于降水,气温对位于南部平原的耕地kNDVI有一定负面影响,而城乡、工矿、居民用地kNDVI受气温的负面影响最大。【结论】京津冀地区植被变化对降水的积极响应更强,不同土地利用类型kNDVI对气候因子响应具有区域空间差异。

关键词：植被变化 kNDVI 气候因子 SHAP解释方法京津冀

维普期刊数据库博看期刊

Adhesive Contact of Elastic Solids with Self-Affine Fractal Rough Surfaces

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Acta Mechanica Solida Sinica 2024年第2期37卷 265-270页

作者： Xuan-Ming Liang Shi-Wen Chen Si-he wang Zhen-Yuan Gong Jun feng Gang-feng wang Department of Engineering Mechanics SVL and MMMLXi’an Jiaotong UniversityXi’an710049China OPPO Mobile Telecommunications Corporation Ltd. Dongguan523860China

The elastic adhesive contact of self-affine fractal rough surfaces against a rigid flat is simulated using the finite element method. An array of nonlinear springs, of which the force-separation law obeys the Lennard–Jones potential, is introduced to account for the interfacial adhesion. For fractal rough surfaces, the interfacial interaction is generally attractive for large mean gaps, but turns repulsive as the gap continuously shrinks. The interfacial interactions at the turning point corresponding to the spontaneous contact are shown for various surfaces. For relatively smooth surfaces, the probability density distributions of repulsion and attraction are nearly symmetric. However, for rougher surfaces, the simulation results suggest a uniform distribution for attraction but a monotonously decreasing distribution with a long tail for repulsion. The pull-off force rises with increasing ratio of the work of adhesion to the equilibrium distance, whereas decreases for solids with a higher elastic modulus and a larger surface roughness. The current study will be helpful for understanding the adhesion of various types of rough solids.

关键词： Fractal rough surfaces Adhesion Contact mechanics Lennard-Jones potential

The study of lithographic variation in resistive random access memory

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Journal of Semiconductors 2024年第5期45卷 69-79页

作者： Yuhang Zhang Guanghui he feng Zhang Yongfu Li Guoxing wang Department of Micro-Nano Electronics Shanghai Jiao Tong UniversityShanghai 200240China MoE Key Lab of Artificial Intelligence Shanghai Jiao Tong UniversityShanghai 200240China Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China

Reducing the process variation is a significant concern for resistive random access memory(RRAM).Due to its ultrahigh integration density,RRAM arrays are prone to lithographic variation during the lithography process,introducing electrical variation among different RRAM *** this work,an optical physical verification methodology for the RRAM array is developed,and the effects of different layout parameters on important electrical characteristics are systematically *** results indicate that the RRAM devices can be categorized into three clusters according to their locations and lithography *** read resistance is more sensitive to the locations in the array(~30%)than SET/RESET voltage(he increase in the RRAM device length and the application of the optical proximity correction technique can help to reduce the variation to less than 10%,whereas it reduces RRAM read resistance by 4×,resulting in a higher power and area *** such,we provide design guidelines to minimize the electrical variation of RRAM arrays due to the lithography process.

关键词： layout lithography process variation resistive random access memory

Review on frost resistance and anti-clogging of pervious concrete

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 481-496页

作者： Zhuo wang Zhichen Liu feng Zeng Kun he Shuaicheng Guo China Railway Construction Group Co. Ltd.Beijing 100040China State Key Laboratory of Bridge Safety and Resilience College of Civil EngineeringHunan UniversityChangsha 410082China

Pervious concrete is a special type of concrete that is of high porosity and contains no or a small amount of fine aggregate,and it is an important basic material for sponge city *** presence of a large number of connected pores inside pervious concrete leads to a marked difference in durability failure mechanism compared with that of ordinary *** this study,the frost resistance and anti-clogging of pervious concrete were introduced in detail,and the methods to improve their performance were summarized *** cracking pattern of pervious concrete is influenced by geometric characteristics and three-dimensional morphological features of pores,resulting in its crack generation,development,and geometry being significantly different from those of ordinary concrete,thus leading to different freeze-thaw cycle *** addition,due to its different pore structure compared to ordinary concrete,three types of clogging mechanisms,affecting the long-term permeability of pervious concrete were elaborated systematically(i.e.,physical clogging,biological clogging,and chemical clogging).And the ways to improve the anti-clogging of pervious concrete are systematically presented from multiple ***,in order to broaden the engineering applications of pervious concrete,some research proposals are presented in this study.

关键词： Pervious concrete Connected pore Frost resistance Clogging mechanism