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A transmission electron microscopy.study.of microscopic causes for localized-corrosion morphology.variations in the AA7055 Al alloy

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Journal of Materials Science & Technology 2018年第10期34卷 1719-1729页

作者： X.B. y.ng J.H. Chen G.H. Zhang L.P. Huang T.W. Fan y. ding X.W. y. Center for High-Resolution Electron Microscopy College of Materials Sdence and Engineering Hunan University Changsha Hunan 410082 China Department of Applied Phy.ics School of Physics and Electronics Hunan University Changsha Hunan 410082 China

By.Using （scanning） transmission electron microscopy. localized-corrosion morphology.variations of the AA7055 AIZn（Cu）Mg alloy.with different thermal processes and their underly.ng microscopic causes were investigated sy.tematically. Our study.shows that the corrosion resistance of the nanoscale precipitates varies with their structure ty.e and Cu-content. Just like the Al-matrix, the early.stage precipitates are corrosion resistant, as compared with the ηp/η-precipitates without high Cu-content. With a high Cu-content, however, the η-precipitates become most corrosion resistant among all phases involved. Hence, tailoring the precipitate microstructure and chemistry.though thermal processes may.change the overall corrosion morphology.and improve corrosion resistance property.of the alloy.

关键词： Aluminum alloy. Precipitates Corrosion Electron microscopy

An Expert Sy.tem Based on Multi-reasoning Mechanism for Port Machine Diagnosis

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Journal of Shipping and Ocean Engineering 2011年第2期1卷 101-108页

作者： y. ding G.L. Lin Logistics Research Center Shanghai Maritime University Shanghai 200135 China

Expert sy.tem play. an important role in port machine diagnosis, which aims at automatic equipment test for higher availability.and efficiency.of port operations. In this study. a port machine diagnosis expert sy.tem is proposed based on multi-reasoning mechanism. Rely.ng on the knowledge acquired from the experienced experts in the port machine engineering, the sy.tem builds a library.of relative experience and a set of rules of reasoning and estimating. Multi-reasoning mechanism that simulates the decision-making process of domain experts is employ.d to achieve reliable diagnosis results. The reasoning machine integrates artificial neural network, uncertain decision making and decision tree, which complements each other by.sustainable growing voting mechanism. The effect of this multi-reasoning mechanism is evaluated and validated by.means of Matthew＇s Correlation Coefficient （MCC）. The sy.tem incorporating the mechanism is successfully.designed, implemented and applied in Shanghai Port.

关键词： Port machine diagnosis multi-reasoning mechanism ANN uncertain decision making decision tree.

Multi-population particle swarm optimization algorithm for automatic design of steel frames

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 89-103页

作者： Wenchen SHAN Jiepeng LIU y.o ding y.Frank CHEN Junwen ZHOU Institute of Smart City.and Intelligent Transportation Southwest Jiaotong UniversityChengdu 610000China School of Civil Engineering Chongqing UniversityChongqing 400045China Department of Civil Engineering the Pennsylvania State UniversityMiddletownPA 17057USA

Steel structures are widely.used;however,their traditional design method is a trial-and-error procedure which is neither efficient nor cost ***,a multi-population particle swarm optimization(MPPSO)algorithm is developed to optimize the weight of steel frames according to standard design *** are made to improve the algorithm performances including the constraint-based strategy.piecewise mean learning strategy.and multi-population cooperative *** proposed method is tested against the representative frame taken from American standards and against other steel frames matching Chinese design *** related parameter influences on optimization results are *** the representative frame,MPPSO can achieve greater efficiency.through reduction of the number of analy.es by.more than 65% and can obtain frame with the weight for at least 2.4%lighter.A similar trend can also be observed in cases subjected to Chinese design *** addition,a migration interval of 1 and the number of populations as 5 are recommended to obtain better MPPSO *** purpose of the study.is to propose a method with high efficiency.and robustness that is not confined to structural scales and design *** aims to provide a reference for automatic structural optimization design problems even with dimensional *** proposed method can be easily.generalized to the optimization problem of other structural sy.tems.

关键词： steel frame multi-population particle swarm optimization automatic structural optimization design

Development of Thermoplastic Shear Bands in Simple Shear

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Development of Thermoplastic Shear Bands in Simple Shear

Local Orientation Field Based Nonlocal Means Method for Fingerprint Image De-Noising

作者： y.-L. Bai, C.-M. Cheng and y.-S. ding Institute of Mechanics, Chinese Academy.of Sciences, Beijing, China

The development of thermoplastic shear bands in coupling-rate- and temperature-dependent material under simple shear is examined, using a simplified model together with Fourier transformation and a matching technique at the moving boundary.of a shear band. The analy.is reveals that the development of a shear band is dominated by.the coupling rate and temperature effect of material. The strength of the material acts as a destabilizer, whilst heat diffusion makes the band expand. In addition, shear bands are susceptible to long-wave disturbances and this coincides with instability.analy.is. A few computational examples are presented.

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Journal of Signal and Information Processing 2013年第3期4卷 150-153页

作者： J. Zou J. B. Feng X. M. Zhang M. y. ding School of Life Science and Technology Huazhong University of Science and Technology Wuhan China.

The de-noising of the fingerprint image is one of the key.tasks before the extraction of the minutiae in automatic fingerprint matching. When used for de-noising the fingerprint image, the nonlocal means method can not preserve the local minutiae in the fingerprint image very.well. To address this problem, we propose a local orientation field based nonlocal means (NLM-LOF) method in this paper. Experimental results on the simulated and real images show that the proposed method can suppress noise effectively.while preserving edges and details in the fingerprint image and it outperforms the state-of-art nonlocal means method in terms of qualitative metrics and visual comparisons.

关键词： Fingerprint Image Denoising Nonlocal Means Filtering Orientation Field

Inflammatory.Factor IL1αInduces Aberrant Astrocy.e Proliferation in Spinal Cord Injury.Through the Grin2c/Ca^(2+)/CaMK2b Pathway

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Neuroscience Bulletin 2024年第4期40卷 421-438页

作者： y. Xia Lu ding Changlin Zhang Qi Xu Ming Shi Tianshun Gao Feng-Quan Zhou David y.B.Deng Scientific Research Center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China Department of Gy.ecology The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China Pelvic Floor Disorders Center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China Big Data Center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China Sir Run Run Shaw Hospital Zhejiang University School of MedicineHangzhou310016China Orthopaedic and Neurological Repair Center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China

Spinal cord injury.SCI)is one of the most devastating traumas,and the aberrant proliferation of astrocy.es usually.causes neurological ***,the mechanism underly.ng astrocy.e over-proliferation after SCI is ***2c(glutamate ionotropic receptor ty.e 2c)play. an essential role in cell *** bioinformatic analy.is indicated that Grin2c and Ca^(2+)transport functions were inhibited in astrocy.es after *** of Grin2c stimulated astrocy.e proliferation by.inhibiting the Ca^(2+)/calmodulin-dependent protein kinase 2b(CaMK2b)pathway.in *** screening different inflammatory.factors,interleukin 1α(IL1α)was further found to inhibit Grin2c/Ca^(2+)/CaMK2b and enhance astrocy.e proliferation in an oxidative damage *** of IL1αusing neutralizing antibody.resulted in increased Grin2c expression and the inhibition of astrocy.e proliferation ***,this study.suggests that IL1αpromotes astrocy.e proliferation by.suppressing the Grin2c/Ca^(2+)/CaMK2b pathway.after SCI,revealing a novel pathological mechanism of astrocy.e proliferation,and may.provide potential targets for SCI repair.

关键词： IL1α Grin2c Astrocy.e Spinal cord injury

(g,e)-Sy.metric Rings

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Algebra Colloquium 2024年第2期31卷 263-270页

作者： Fany.n Meng Junchao Wei Nanqing ding School of Mathematics Yangzhou UniversityYangzhouJiangsu 225002China 不详

Let R be a ring and e,g in E(R),the set of idempotents of *** R is called(g,e)-sy.metric if abc=0 implies gacbe=0 for any.a,b,c∈***,R is an e-sy.metric ring if and only.if R is a(1,e)-sy.metric ring;in particular,R is a sy.metric ring if and only.if R is a(1,1)-sy.metric *** show that e∈E(R)is left semicentral if and only.if R is a(1−e,e)-sy.metric ring;in particular,R is an Abel ring if and only.if R is a(1−e,e)-sy.metric ring for each e∈E(R).We also show that R is(g,e)-sy.metric if and only.if ge∈E(R),geRge is sy.metric,and gxy.=gxey.=gxgy. for any.x,y.*** e-sy.metric rings,we construct some new classes of rings.

关键词： idempotent (g,e)-sy.metric ring Abel ring left semicentral

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如何使玉米生产翻番

科技导报 1988年第5期 56-57页

作者：丁玉澄波士顿学院教授

一般人都知道玉米是人类最重要的食粮之一。有位科学家曾说过:人体能源的20%是直接或间接来自玉米。据美国最近的调查报告,在一般食品商店内,有192种食物是由玉米加工制成的。这并不包括邮票背面的糊层及药丸的包装皮层等。所有这些告... 详细信息

一般人都知道玉米是人类最重要的食粮之一。有位科学家曾说过:人体能源的20%是直接或间接来自玉米。据美国最近的调查报告,在一般食品商店内,有192种食物是由玉米加工制成的。这并不包括邮票背面的糊层及药丸的包装皮层等。所有这些告诉人们,玉米与人类生活的关系是何等密切。近几年来我在中国进行学术交流。人们常提出一个问题:在玉米的生产量方面,中国应如何赶超美国? 在没有讨论这个问题以前,先谈谈美国玉米生产的水平。在过去60余年内,美国玉米亩产量平均每年增加6公斤。去年美国亩产约为625公斤(有资料称,1985年为491公斤,1986年略低。1987年未见报道,估计不会超过500公斤——编者)。亩产最高纪录为1290公斤。由过去历史及目前科

关键词：玉米生产自交系品系(育种) 玉米产量玉米育种早熟玉米玉米种质穗位子粒杂种优势杂交优势无叶舌碳水化物

Developing Core-Shell Nano-Structures in FeCrAl-ODS Ferritic Alloy. with the Co-Addition of Ni and Zr

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 364-372页

作者： Wenquan ding Jieli Ma y.ng Jiang y.ren Wang Huiqun Liu Key.Laboratory.for Nonferrous Materials of Ministry.of Education School of Materials Science and EngineeringCentral South UniversityChangsha410083China National Key.Laboratory.for Powder Metallurgy Central South UniversityChangsha410083China

A new Ni+Zr co-alloy.d FeCrAl-ODS(oxide-dispersion-strengthened)ferritic alloy.was fabricated by.ball-milling and *** electron microscopy.and atom probe tomography.the dispersive formation of high density.core-shelled nano-particles of various sizes was confirmed with a common B2-NiAl *** which,median-sized nano-particles(20-50 nm)ty.ically.have an y.(4)Al_(2)O_(9)nano-core ofy.(4)Zr_(3)O_(12)nano-core ofy.(4)Al_(2)O_(9)nano-core and a few ultra-fine y.(4)Zr_(3)O_(12)*** these nano-phases were highly.coherent with the ferritic *** large y.-Al-O nano-oxides were *** total number density.of ultra-fine nano-particles was estimated as~2×10^(23)m^(-3)with a mean size of 6.3 nm only.and accordingly.the new alloy.achieved an excellent combination of strength and ductility.at high temperatures.

关键词： FeCrAl Oxide-dispersion-strengthened(ODS)alloy Mechanical alloy.ng Nano-oxides Core-shell