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Chinese Journal of Polymer Science 2023年第8期41卷 1261-1268,I0009页

作者： Jia-Qiang li Wen-shuang li Wen-Ting Zhang Shu Zhu Chu-Yang Luo Wan-shuang liu li-Ying Zhang Shanghai Collaborative Innovation Center of High Performance Fibers and Composite(Province-Ministry Joint) Center for Civil Aviation CompositesDonghua UniversityShanghai 201620China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China Shanghai Donghua Composites Technology Co.Ltd. Shanghai 201620China Key Laboratory of Textile Science&Technology College of TextilesDonghua UniversityShanghai 201620China

Thermoplastic polyimides(PIs)with shape memory potential have received growing attention in recent *** this work,highperformance thermoplastic PIs were fabricated by introducing PIs with chain rigidity(r-PI)into PI with chain flexibility(f-PI).The influences of molecular chain entanglement andπ-πinteractions on their thermomechanical and shape memory properties were *** degree of molecular chain entanglement was quantitively characterized based on dynamic mechanical analysis(DMA).Theπ-πinteractions were investigated in detail by X-ray diffraction(XRD)and UV-Vis *** was found that the entanglement density increased andπ-πinteractions became stronger with the introduction of r-PI into f-PI,leading to the improvement of shape ***,a broad and increased glass transition temperature(T_(g))was achieved,endowing the PIs with multiple shape memory *** synergistic effects of increased entanglement density and enhancedπ-πinteractions were beneficial to regulating interchain interactions and thereby achieving high shape memory performance of the PIs.

关键词： Shape memory polyimide Molecular chain entanglement r-r Stacking

Layer-wise domain correction for unsupervised domain adaptation

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Frontiers of Information Technology & Electronic Engineering 2018年第1期19卷 91-103页

作者： shuang li Shi-ji SONG Cheng WU Automation Department Tsinghua University

Deep neural networks have been successfully applied to numerous machine learning tasks because of their impressive feature abstraction ***,conventional deep networks assume that the training and test data are sampled from the same distribution,and this assumption is often violated in real-world *** address the domain shift or data bias problems,we introduce layer-wise domain correction(LDC),a new unsupervised domain adaptation algorithm which adapts an existing deep network through additive correction layers spaced throughout the *** the additive layers,the representations of source and target domains can be perfectly *** corrections that are trained via maximum mean discrepancy,adapt to the target domain while increasing the representational capacity of the *** requires no target labels,achieves state-of-the-art performance across several adaptation benchmarks,and requires significantly less training time than existing adaptation methods.

关键词： Unsupervised domain adaptation Maximum mean discrepancy Residual network Deep learning

Efficient high-accuracy north-south station-keeping strategy for geostationary satellites

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Science China(Technological Sciences) 2021年第11期64卷 2415-2426页

作者： HUANG XuXing YANG Bin li shuang WANG ZhenBo College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Mechanical Aerospaceand Biomedical EngineeringUniversity of TennesseeKnoxvilleTN 37996USA

Station-keeping(SK) is indispensable in actual geostationary(GEO) satellite missions. Due to the luni-solar gravity perturbations, the inclination of a GEO satellite suffers the issues of secular drift and long-period oscillation. Current north-south(NS)SK strategies maintain the GEO satellite’s orbit with high accuracy but low fuel efficiency. In this work, an efficient highaccuracy NS-SK strategy is developed for the GEO satellites. First, an averaging method is employed to decrease the accumulation of the secular drift within a one-solar-day SK cycle, while the long-period oscillation caused by the solar gravity is damped to further improve the orbital accuracy using the impulse and finite-thrust propulsions. Second, we contribute a fueloptimal cycle that reduces the fuel consumption and a fixed-interval cycle that executes SK control in fixed time interval every day to further enhance the proposed NS-SK strategy. Numerical simulations show that the improved strategy can achieve highaccuracy NS-SK with little fuel consumption. Moreover, results also demonstrate that the fixed-interval cycle can reach higher NS-SK accuracy while consuming less fuel.

关键词： geostationary orbit north-south station-keeping long-period oscillation fuel-optimal fixed-interval

Color Context Binary Pattern Using Progressive Bit Correction for Image Classification

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Chinese Journal of Electronics 2021年第3期30卷 471-481页

作者： SONG Tiecheng FENG Jie li shuang ZHANG Tianqi School of Communication and Information Engineering Chongqing University of Posts and Telecommunications

Local binary pattern(LBP) is sensitive to noise. Noise-resistant LBP(NRLBP) addresses this problem by thresholding local neighboring pixels into three-valued states(i.e., 0, 1 and uncertain bits)and recovering uncertain bits via an error-correction mechanism. In this paper, we extend NRLBP to deal with color images and propose a robust color image descriptor called Color context binary pattern(CCBP). In CCBP, we employ scale context and neighbor context to progressively correct the encoded bits. First, we encode intra-channel local neighboring pixels into three-valued states in scale space and use majority voting to correct all states across scales. Then, we compute inter-channel color feature distances and correct the uncertain bits via neighboring bit propagation. Finally, we construct the image descriptor by concatenating all histograms based on the corrected binary codes. Experiments on four benchmark databases demonstrate the robustness of CCBP for color image classification under very low signal-to-noise ratio levels.

关键词： scale context intra-channel local neighboring pixels image classification color images corrected binary codes color image classification feature extraction local binary pattern bit propagation NRLBP three-valued states CCBP image coding binary codes progressive bit correction error correction codes uncertain bits Color context binary pattern neighbor context inter-channel color feature distances robust color image descriptor image texture error-correction mechanism noise-resistant LBP image colour analysis encoded bits

Resilience assessment and optimization method of city road network in the post-earthquake emergency period

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 765-779页

作者： Wang Haoran Xiao Jia li shuang Zhai Changhai Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information TechnologyHarbin Institute of TechnologyHarbin 150090China

The post-earthquake emergency period,which is a sensitive time segment just after an event,mainly focuses on saving life and restoring social *** improve the seismic resilience of city road networks,a resilience evaluation method used in the post-earthquake emergency period is *** road seismic damage index of a city road network can consider the influence of roads,bridges and buildings along the roads,*** road capacity after an earthquake.A function index for a city road network is developed,which reflects the connectivity,redundancy,traffic demand and traffic function of the *** optimization model for improving the road repair order in the post-earthquake emergency period is also developed according to the resilience evaluation,to enable decision support for city emergency management and achieve the best seismic resilience of the city road *** optimization model is applied to a city road network and the results illustrate the feasibility of the resilience evaluation and optimization method for a city road network in the post-earthquake emergency period.

关键词： city road network post-earthquake emergency period traffic demand resilience evaluation optimization model

Hybrid method for accurate multi-gravity-assist trajectory design using pseudostate theory and deep neural networks

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Science China(Technological Sciences) 2022年第3期65卷 595-610页

作者： YANG Bin FENG JingLang HUANG XuXing li shuang College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing 211106China Department of Mechanical&Aerospace Engineering University of StrathclydeGlasgow G11XJUK

This paper presents a novel hybrid method to design the continuous and accurate multi-gravity-assist trajectory for a high-fidelity *** gravitational perturbation of the primary body is considered during the gravity *** pseudostate technique is applied to approximate the gravity-assisted trajectory,where the optimal sweepback duration is solved using a trained deep neural *** major factors that affect the optimal sweepback duration of the approach and departure segments are *** results show that the optimal sweepback duration of the approach segment only relies on the shape of the approach trajectory and is independent of the flight ***,a gravity-assisted trajectory patched strategy and a hybrid algorithm combining the particle swarm optimization and the sequential quadratic programming are developed to optimize the multi-gravity-assist *** proposed hybrid method is applied to the Europa orbiter *** comparison with the traditional patched conic method,this method demonstrates outstanding performance on accuracy and significantly reduces the computational time and complexity of the trajectory correction with the high-fidelity dynamics.

关键词： pseudostate theory multiple gravity assist deep neural network trajectory optimization Jovian system

Metaplastic carcinoma of the right breast and simultaneous giant ovarian teratoma:a case report

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Chinese Journal of Cancer 2012年第10期31卷 500-504页

作者： shuang li Qing-Zhu Wei Department of General Surgery 2Department ofPathology The Third Affiliated Hospital Southern Medical UniversityGuangzhou Guangdong 510630 P. R. China.

We describe here a female patient who presented with a breast mass and giant abdominal *** needle aspiration cytology of the breast mass and histological examination after modified radical mastectomy confirmed metaplastic carcinoma of the *** epithelial components were formed by infiltrating ductal carcinoma with poor differentiation,and the sarcomatous components were formed by fibrosarcoma and *** examination of the abdominal mass confirmed ovarian *** patient underwent modified radical mastectomy of the right breast and laparoscopic excision of the abdominal mass in the lower right *** underwent six courses of chemotherapy,the patient is now in her tenth month after surgery and under follow-up,and she has no relapsed *** two diseases have never seen in one patient *** case we report here provides some new data for research and clinical experience and it may also provide a new insight into the relationship between metaplastic breast carcinoma and ovarian teratoma.

关键词：乳房肿块乳腺癌畸胎瘤病例报告卵巢病理组织学检查纤维肉瘤分化程度

Effect of Langmuir circulation on upper ocean mixing in the South China Sea

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Acta Oceanologica Sinica 2013年第3期32卷 28-33页

作者： li shuang SONG Jinbao FAN Wei Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciences Department of Ocean Science and Engineering Zhejiang University

Effect of Langmuir circulation （LC） on upper ocean mixing is investigated by a two-way wave-current coupled model. The model is coupled of the ocean circulation model ROMS （regional ocean modeling system） to the surface wave model SWAN （simulating waves nearshore） via the model-coupling toolkit. The LC already certified its importance by many one-dimensional （1D） research and mechanism analysis work. This work focuses on inducing LC＇s effect in a three-dimensional （3-D） model and applying it to real field modeling. In ROMS, the Mellor-Yamada turbulence closure mixing scheme is modified by including LC＇s effect. The SWAN imports bathymetry, free surface and current information from the ROMS while exports signifi- cant wave parameters to the ROMS for Stokes wave computing every 6 s. This coupled model is applied to the South China Sea （SCS） during September 2008 cruise. The results show that LC increasing turbulence and deepening mixed layer depth （MLD） at order of O （10 m） in most of the areas, especially in the north part of SCS where most of our measurements operated. The coupled model further includes wave break- ing which will brings more energy into water. When LC works together with wave breaking, more energy is transferred into deep layer and accelerates the MLD deepening. In the north part of the SCS, their effects are more obvious. This is consistent with big wind event in the area of the Zhujiang River Delta. The shallow water depth as another reason makes them easy to influence the ocean mixing as well.

关键词： Langmuir circulation upper ocean mixing wave breaking South China Sea

Effect of Stokes drift on upper ocean mixing

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Acta Oceanologica Sinica 2008年第2期27卷 11-20页

作者： li shuang SONG Jinbao SUN Qun Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate School Chinese Academy of Sciences Beijing 100039 China

Stokes drift is the main source of vertical vorticity in the ocean mixed layer. In the ways of Coriolis - Stokes forcing and Langmuir circulations, Stokes drift can substantially affect the whole mixed layer. A modified Mellor-Yamada 2. 5 level turbulence closure model is used to parameterize its effect on upper ocean mixing conventionally. Results show that comparing surface heating with wave breaking, Stokes drift plays the most important role in the entire ocean mixed layer, especially in the subsurface layer. As expected, Stokes drift elevates both the dissipation rate and the turbulence energy in the upper ocean mixing. Also, ilffluence of the surface heating, wave breaking and wind speed on Stokes drift is investigated respectively. Research shows that it is significant and important to assessing the Stokes drift into ocean mixed layer studying. The laboratory observations are supporting numerical experiments quantitatively.

关键词： Stokes drift Langmuir circulations Coriolis - Stokes forcing upper ocean mixing Mellor-Yamada 2. 5 turbulence model wave breaking surface heating

High-mobility spin-polarized two-dimensional electron gas at the interface of LaTiO_(3)/SrTiO_(3)(110)heterostructures

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Frontiers of physics 2024年第5期19卷 129-141页

作者： Zhao-Cai Wang Zheng-Nan li shuang-shuang li Weiyao Zhao Ren-Kui Zheng School of Physics and Materials Science Nanchang UniversityNanchang 330031China Department of Materials Science&Engineering Monash UniversityClayton VIC 3800Australia School of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China

High-quality antiferromagnetic Mott insulator thin films of LaTiO_(3)(LTO)were epitaxially grown onto SrTiO_(3)(STO)(110)substrates using the pulsed laser *** LTO/STO heterostructures are not only highly conducting and ferromagnetic,but also show Kondo effect,Shubnikov‒de Haas(SdH)oscillations with a nonzero Berry phase ofπ,and lowfield hysteretic negative magnetoresistance(MR).Angle-dependent SdH oscillations and a calculation of the thickness of the interfacial conducting layer indicate the formation of a 4-nm high mobility two-dimensional electron gas(2DEG)layer at the ***,an amazingly large lowfield negative MR of∼61.8%is observed at 1.8 K and 200 Oe,which is approximately one to two orders of magnitude larger than those observed in other spin-polarized 2DEG oxide *** these results demonstrate that the 2DEG is spin-polarized and the 4-nm interfacial layer is ferromagnetic,which are attributed to the presence of magnetic Ti^(3+)ions due to interfacial oxygen vacancies and the diffusion of La^(3+)ions into the STO *** localized Ti^(3+)magnetic moments couple to high mobility itinerant electrons under magnetic fields,giving rise to the observed lowfield *** work demonstrates the great potential of antiferromagnetic titanate oxide interface for designing spin-polarized 2DEG and spintronic devices.

关键词： two-dimensional electron gas heterostructure spin polarization electronic transport interface