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A Novel Fine-Grained Method for Vehicle Type Recognition Based on the Locally Enhanced PCANet Neural Network

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Journal of Computer Science & Technology 2018年第2期33卷 335-350页

作者： Qian Wang You-dong ding School of Computer Enqineering and Science Shan qhai University Shanqhai 200072 China Information Center Criminal Investigation Department of Shanghai Public Security Bureau Shanghai 200083 China Shanghai Engineering Research Center of Motion Picture Special Effects Shanghai 200072 China Shanghai Film Academy Shanghai University Shanghai 200072 China

In this paper, we propose a locally enhanced PCANet neural network for fine-grained classification of vehicles. The proposed method adopts the PCANet unsupervised network with a smaller number of layers and simple parameters compared with the majority of state-of-the-art machine learning methods. It simplifies calculation steps and manual labeling, and enables vehicle types to be recognized without time-consuming training. Experimental results show that compared with the traditional pattern recognition methods and the multi-layer CNN methods, the proposed method achieves optimal balance in terms of varying scales of sample libraries, angle deviations, and training speed. It also indicates that introducing appropriate local features that have different scales from the general feature is very instrumental in improving recognition rate. The 7-angle in 180° （12-angle in 360°） classification modeling scheme is proven to be an effective approach, which can solve the problem of suffering decrease in recognition rate due to angle deviations, and add the recognition accuracy in practice.

关键词： fine-grained classification PCANet local enhancement vehicle type recognition

Stride Strategy to Enable a Quasi-ergodic Search of Reaction Pathways Demonstrated by Ring-opening Polymerization of Cyclic Esters

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Chinese Journal of Polymer Science 2023年第5期41卷 745-759,I0009页

作者： Wei-Han Rao Lin Yu Jian-dong ding State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China

Coordination-insertion ring-opening polymerization(ROP)of cyclic esters is an industrial way to synthesize polyesters,which are widely applied in biomedical and environment-benign ***,the rate-determining transition state(TS)identified by the conventional reaction pathways(pathway A and pathway B)presented in the literature did not well describe the structure-reactivity *** misidentification of the rate-determining TS might arise from the less ergodicity in the search of reaction ***,we suggested a stride strategy based on the insight that even a partial double bond is rotatable at the catalysis *** a result,we revealed a new reaction pathway,pathway C with a torsion transition state TSC2,by density functional theory(DFT).We also carried out kinetic experiments of ROP of D-lactide(D-LA),L-lactide(L-LA),ε-caprolactone(CL),andδ-valerolactone(VL),using poly(ethylene glycol)as the initiator and stannous octoate as the *** excellent linearity between the calculated free energy barriers and logarithms of the experimental kinetic constants of the two kinds of lactide and lactone monomers,was established,validating the quasi-ergodic search of reaction pathways and the scaling predicted by transition state *** linearity was highly predictive for the other lactide and lactone monomers,demonstrated by glycolide(GA)and trimethylene urethane(TU).

关键词： Coordination-insertion mechanism Ring-opening polymerization Density functional theory Biodegradable polymer Lactide Lactone Cyclic ester

Two Avowable Quantum Communication Schemes

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Communications in Theoretical Physics 2008年第11期50卷 1109-1112页

作者： YAN Feng-Li ding dong College of Physics Science and Information Engineering Hebei Normal University Shijiazhuang 050016 China North China Institute of Science and Technology Langfang 101601 China

Two avowable quantum communication schemes are *** is an avowable teleportation protocolbased on the quantum *** this protocol one teleports a set of one-particle states based on the availabilityof an honest arbitrator,the keys and the Einstein-Podolsky-Rosen pairs shared by the communication parties and *** key point is that the fact of the teleportation can neither be disavowed by the sender nor be denied bythe *** is an avowable quantum secure direct communication scheme.A one-way Hash function chosenby the communication parties helps the receiver to validate the truth of the information and to avoid disavowing for thesender.

关键词： avowable teleportation avowable quantum secure direction communication EPR pairs Hash function

Entangler and analyzer for multiphoton Greenberger-Horne-Zeilinger states using weak nonlinearities

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Science China(Physics,Mechanics & Astronomy) 2014年第11期57卷 2098-2103页

作者： ding dong YAN FengLi GAO Ting College of Physics Science and Information Engineering Hebei Normal University Department of Basic Curriculum North China Institute of Science and Technology College of Mathematics and Information Science Hebei Normal University

In the regime of weak nonlinearity we present two general,feasible schemes for manipulating photon *** is an entangler for generating any one of the n-photon Greenberger-Horne-Zeilinger(GHZ)*** of the incoming photons with crossKerr media followed by a phase shift gate and a measurement on a probe beam plus appropriate local operations using classical feed-forward of the measurement results allow one to obtain the desired states in a nearly deterministic *** second scheme discussed is an analyzer for multiphoton maximally entangled states,which is derived from the above *** this scheme,all of the 2nn-photon GHZ states can,nearly deterministically,be discriminated.

关键词： entangled photon entanglement generating coherent operations deterministic desired superposition optics

Static Recrystallization Behavior of SA508-III Steel during Hot Deformation

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Journal of Iron and Steel Research International 2016年第5期23卷 466-474页

作者： ding-qian dong Fei CHEN Zhen-shan CUI Institute of Forming Technology and Equipment Shanghai Jiao Tong University College of Manufacturing Science and Engineering Southwest University of Science and Technology

The static recrystallization behavior of SA508-III steel was investigated by isothermal double-hit hot compression tests at the deformation temperature of 950-1 250 ℃,the strain rate of 0. 01-1 s^（-1）,and the inter-pass time of 1-300 *** effects of deformation parameters,including forming temperature,strain rate,degree of deformation（ pre-strain） and initial austenite grain size,on the softening kinetics were analyzed. Experimental results show that static recrystallization kinetics is strongly dependent on deformation temperature and degree of deformation,while less affected by the strain rate and initial grain size. The kinetics and microstructural evolution equations of static recrystallization for SA508-III steel were developed to predict the softening behavior and the statically recrystallized grain size,respectively. Based on the comparison between the experimental and predicted results,it is found that the established equations can give a reasonable estimate of the static softening behavior for SA508-III steel.

关键词： softening fraction static recrystallization kinetic equation microstructure SA508-III steel

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

Tribology of nitriding layer, TiN coatings and their complex on AISI D2 steel

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 383-385页

作者： WANG Ke-sheng ZHANG De-yuan dong ding-fu College of Materials Science and Engineering Hefei University of Technology Hefei 230009 China Yu King Industrial Company Limited Shenzhen 518103 China College of Materials Science and Engineering Hefei University of Technology Hefei 230009 China National R&D Centre for Surface Engineering of China Shenzhen 518029 China College of Materials Science and Engineering Hefei University of Technology Hefei 230009 China

The sliding wear and impact wear resistances of D2 steel with nitriding layer, PVD titanium nitride coating and their duplex treatment were investigated. The experimental results suggest that the duplex treatment has the best sliding and impact wear resistances under experimental conditions. And the wear resistance of PVD titanium nitride is better than that of nitriding. The impact wear resistance and wear mechanism of all three surface layers remain unchanged under impact load of 0.2 J or 1 J. All samples end with the same symptom of flaking.

关键词： wear resistance titanium nitride nitriding duplex treatment

A Comparative Study on the Post-Buckling Behavior of Reinforced Thermoplastic Pipes(RTPs)Under External Pressure Considering Progressive Failure

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China Ocean Engineering 2024年第2期38卷 233-246页

作者： ding Xin-dong WANG Shu-qing LIU Wen-cheng YE Xiao-han College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China Department of Marine Technology Norwegian University of Science and Technology(NTNU)Trondheim NO-7491Norway

The collapse pressure is a key parameter when RTPs are applied in harsh deep-water *** investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are *** the numerical simulations,the eigenvalue analysis and Riks analysis are combined,in which the Hashin failure criterion and fracture energy stiffness degradation model are used to simulate the progressive failure of composites,and the“infinite”boundary conditions are applied to eliminate the boundary *** for the hydrostatic pressure tests,RTP specimens were placed in a hydrostatic chamber after filled with *** has been observed that the cross-section of the middle part collapses when it reaches the maximum *** collapse pressure obtained from the numerical simulations agrees well with that in the ***,the applicability of NASA SP-8007 formula on the collapse pressure prediction was also *** has a relatively greater difference because of the ignorance of the progressive failure of *** the parametric study,it is found that RTPs have much higher first-ply-failure pressure when the winding angles are between 50°and 70°.Besides,the effect of debonding and initial ovality,and the contribution of the liner and coating are also discussed.

关键词： reinforced thermoplastic pipes post-buckling behavior progressive failure of composites debonding initial ovality

Potential shift of bacterial community structure and corrosion-related bacteria in drinking water distribution pipeline driven by water source switching

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Frontiers of Environmental Science & Engineering 2021年第2期15卷 117-126页

作者： Yue Hu ding dong Kun Wan Chao Chen Xin Yu Huirong Lin Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Research Institute for Environmental Innovation(Suzhou) TsinghuaSuzhou 215163China College of Environment&Ecology Xiamen UniversityXiamen 361102China School of Environment Tsinghua UniversityBeijing 100084China Department of Environmental Science and Engineering College of Chemical EngineeringHuaqiao UniversityXiamen 361021China

As a result of pollution in the present water sources,cities have been forced to utilize cleaner water *** are few reports regarding the potential shift of bacterial community structure driven by water source switching,especially that of corrosion-related *** types of finished water were used for simulation,the polluted source water from the Qiantang and dongtiaoxi Rivers(China)was replaced by cleaner water from Qiandao Lake(China).Here,we discussed the transition effects through three simulated *** bacterial characteristics were identified using the highthroughput sequencing and heterotrophic plate count *** was observed that the level of culturable bacteria declined by 2–3 orders of magnitude after water source *** bacterial community released from the pipeline reactor was significantly different under different finished water,and it exhibited large variation at the genus ***(58.2%)and Phreatobacter(14.5%)clearly replaced Novosphingobium,Aquabacterium,and Cupriavidus as new dominant genera in system A,which could be attributed to the lower carbon and nitrogen content of the new water *** corrosion-inhibiting bacteria decreased after switching,they still maintained dominant in three reactors(6.6%,15.9%,and 19.7%).Furthermore,potential opportunistic pathogens such as Sphingomonas were *** study shows that after transition to a high quality water source,the total culturable bacteria released was in a downtrend,which leads to a great reduction in the risk of bacterial leakage in the produced drinking water.

关键词： Drinking water biosafety Water source switching Drinking water distribution system Transition effects High-throughput sequencing