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Two-level hierarchical feature learning for image classification

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Frontiers of Information Technology & Electronic Engineering 2016年第9期17卷 897-906页

作者： Guang-hui SONG xiao-gang JIN Gen-lang CHEN Yan nie College of Computer Science and Technology Zhejiang University Ningbo Institute of Technology Zhejiang University College of Science and Technology Ningbo University

In some image classification tasks, similarities among different categories are different and the samples are usually misclassified as highly similar categories. To distinguish highly similar categories, more specific features are required so that the classifier can improve the classification performance. In this paper, we propose a novel two-level hierarchical feature learning framework based on the deep convolutional neural network(CNN), which is simple and effective. First, the deep feature extractors of different levels are trained using the transfer learning method that fine-tunes the pre-trained deep CNN model toward the new target dataset. Second, the general feature extracted from all the categories and the specific feature extracted from highly similar categories are fused into a feature vector. Then the final feature representation is fed into a linear classifier. Finally, experiments using the Caltech-256, Oxford Flower-102, and Tasmania Coral Point Count(CPC) datasets demonstrate that the expression ability of the deep features resulting from two-level hierarchical feature learning is powerful. Our proposed method effectively increases the classification accuracy in comparison with flat multiple classification methods.

关键词： Transfer learning Feature learning Deep convolutional neural network Hierarchical classification Spectral clustering

Cathodoluminescence and Trace Element Composition of Scheelite from the Middle-Lower Yangtze River Metallogenic Belt(MLYB): Implications for Mineralization and Exploration

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Acta Geologica Sinica(English Edition) 2020年第6期94卷 1977-1996页

作者： nie Liqing ZHOU Taofa CHEN Xuefeng WANG Fangyue xiao Xin Ore Deposit and Exploration Centre(ODEC) School of Resources and Environmental EngineeringHefei University of TechnologyHefei 230009China School of Civil Engineering Anhui Jianzhu UniversityHefei 230601China Anhui Province Engineering Research Center for Mineral Resources and Mine Environments Hefei 230009China

The Middle-Lower Yangtze River Metallogenic Belt(MLYB)is known to contain abundant copper and iron porphyry-skarn deposits,with an increasing number of tungsten deposits and scheelite in Fe-Cu deposits being discovered in the MLYB during recent *** ore genesis of the newly-discovered tungsten mineralization in the MLYB is poorly *** investigate four sets of scheelite samples from tungsten,iron and copper deposits,using CL imaging and LA-ICP-MS techniques to reveal internal zonation patterns and trace element *** REE distribution patterns of four studied deposits show varying degrees of LREE enrichment with negative Eu *** oxygen fugacity of ore-forming fluid increased in Donggushan,while the oxygen fugacity of ore-forming fluid decreased in Ruanjiawan,Guilinzheng and *** scheelites from the Donggushan,Ruanjiawan,Guilinzheng and Gaojiabang deposits show enrichment in LREEs and HFSE,with Nb/La ratios ranging from 1.217 to 52.455,indicating that the four tungsten deposits are enriched in the volatile fluorine.A plot of(La/Lu)N versus Mo/δEu can be used to distinguish quartz vein type,porphyry and skarn tungsten *** study demonstrates that scheelite grains can be used to infer tungsten mineralization and are effective in identifying magmatic types of tungsten deposits in prospective mining sites.

关键词： scheelite trace elements tungsten mineralization Middle-Lower Yangtze River Metallogenic Belt

Multi-model assessment of glacio-hydrological changes in central Karakoram, Pakistan

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Journal of Mountain Science 2021年第8期18卷 1995-2011页

作者： Javed HASSAN CHEN xiao-qing Rijan Bhakta KAYASTHA nie Yong Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu610041China China-Pakistan Joint Research Center on Earth Sciences CAS-HECIslamabad45320Pakistan University of Chinese Academy of Sciences Beijing100049China Himalayan Cryosphere Climate and Disaster Research Center(HiCCDRC)Department of Environmental Science and EngineeringSchool of ScienceKathmandu UniversityKavrepalanchowk45200Nepal

The multi-model assessment of glacio-hydrological regimes can enhance our understanding of glacier response to climate *** improved knowledge can uplift our computing abilities to estimate the contributing components of the river *** study examined and compared the hydrological responses in the glacier-dominated Shigar River basin(SRB)under various climatic scenarios using a semi-distributed Modified Positive Degree Day Model(MPDDM)and a distributed Glacio-hydrological Degree-day Model(GDM).Both glacio-hydrological models were calibrated and validated against the observed hydro-meteorological data from 1988–1992 and 1993–*** and precipitation data from Shigar and Skardu meteorological stations were used along with field estimated degree-day factor,temperature,and precipitation *** results from both models indicate that the snow and ice melt are vital contributors to sustain river flow in the ***,MPDDM estimated 68%of rain and baseflow contribution to annual river runoff despite low precipitation during the summer monsoon,while GDM estimated 14%rain and baseflow ***,MPDDM calculated 32%,and GDM generated 86%of the annual river runoff from snow and ice *** simulated river discharge with 0.86 and 0.78 NSE for calibration and validation,***,GDM simulated river discharge with improved accuracy of 0.87 for calibration and 0.84 NSE for the validation *** snow and ice melt is significant in sustaining river flow in the SRB,and substantial changes in melt characteristics of snow and ice are expected to have severe consequences on seasonal water *** on the sensitivity analysis,both models’outputs are highly sensitive to the variation in ***,compared to MPDDM,GDM simulated considerable variation in the river discharge in climate scenarios,RCP4.5 and 8.5,mainly due to the higher sensitivity of GDM model outputs to temperature *** i

关键词： Modified Positive Degree Day Model(MPDDM) Glacio-hydrological Degree-day Model(GDM) Glacio-hydrological Modelling Climatic Variation Snow and ice contributions

Duplicated transmission based-resource scheduling for uplink grant-free SCMA system

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The Journal of China Universities of Posts and Telecommunications 2020年第2期27卷 1-9页

作者： xiao Jiali nie Gaofeng Deng Gang Tian Hui Zhang Chong School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China National Radio and Television Administration Academy of Broadcasting ScienceBeijing 100102China

Sparse code multiple access-based uplink grant-free transmission(SCMA-UGFT)has been proposed to realize ultra reliable and low latency communication(URLLC)in the fifth generation(5 G)*** the process of resource request and grant,users may collide in the same *** compensate the potential user performance decline,resource scheduling becomes a tough issue in the SCMA-UGFT *** article proposes a duplicated transmission-based resource scheduling(DTBRS)scheme for SCMA-UGFT system by considering the URLLC *** from the existing schemes,not only one shared basic transmission units(BTUs)are allocated to a user equipment(UE)in the proposed DTBRS scheme for initial transmission to realize the duplicated transmission and to guarantee the transmission ***,according to the proposed DTBRS scheme,one or two exclusive BTUs are assigned to a UE for retransmission to avoid the *** last,each packet is given a lifetime to limit the transmission latency to meet the URLLC latency *** simulation demonstrates that the DTBRS scheme can achieve a better performance than the existing state-of-the-art scheme in terms of the average packet drop rate.

关键词： grant-free SCMA resource scheduling URLLC

RIG-I： a multifunctional protein beyond a pattern recognition receptor

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Protein & Cell 2018年第3期9卷 246-253页

作者： xiao-xiao Xu Han Wan Li nie Tong Shao Li-xin Xiang Jian-zhong Shao Key Laboratory for Cell and Gene Engineering of Zhejiang Province College of Life Sciences Zhejiang University Hangzhou 310058 China Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and Technology Qingdao 266235 China

It was widely known that retinoic acid inducible gene I （RIG-I） functions as a cytosolic pattern recognition receptor that initiates innate antiviral immunity by detecting exogenous viral RNAs. However, recent stud- ies showed that RIG-I participates in other various cellular activities by sensing endogenous RNAs under different circumstances. For example, RIG-I facilitates the therapy resistance and expansion of breast cancer cells and promotes T cell-independent B cell activation through interferon signaling activation by recognizing non-coding RNAs and endogenous retroviruses in certain situations. While in hepatocellular carcinoma and acute myeloid leukemia, RIG-I acts as a tumor suppressor through either augmenting STAT1 activation by competitively binding STAT1 against its negative regulator SliP1 or inhibiting AKT-mTOR signaling pathway by directly interacting with Src respectively. These new findings suggest that RIG-I plays more diverse roles in various cellular life activities, such as cell proliferation and differentiation, than previously known. Taken together, the function of RIG-I exceeds far beyond that of a pattern recognition receptor.

关键词： RIG-I viral RNA endogenous RNA immunity cancer

Correlation between ductus venosus spectrum and right ventricular diastolic function in isolated single-umbilical-artery foetus and normal foetus in third trimester

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World Journal of Clinical Cases 2020年第23期8卷 5866-5875页

作者： Tian-Gang Li Fang nie xiao-Yan Xu Department of Ultrasound Diagnosis Gansu Provincial Maternity and Child-Care HospitalLanzhou 730050Gansu ProvinceChina Department of Ultrasound Diagnosis Lanzhou University Second HospitalLanzhou 733000Gansu ProvinceChina

BACKGROUND Single umbilical artery(SUA)is the most common umbilical cord malformation in prenatal *** presence of an SUA can cause blood circulation disorder in the foetus and functional changes of the foetal heart,affecting foetal *** right ventricular diastolic functions in foetuses with isolated SUA and in normal foetuses in the third trimester were evaluated using the spectral Doppler of blood flow in the foetal ductus venosus(DV).AIM To evaluate the right ventricular diastolic functions in foetuses with isolated SUA and in normal foetuses in the third *** Colour Doppler was used to measure the spectrum of foetal DV and tricuspid orifice in 34 foetuses with isolated SUA aged 28-39 wk and in age-matched healthy *** DV flow velocities and velocity ratios were *** early passive/late active(E/A)ratio at the tricuspid orifice and tissue Doppler Tei index of the foetal right ventricular in the two groups were also *** During the third trimester,the isolated SUA group showed a lower‘a’-wave peak velocity in the DV than the control group(P<0.05).The correlations between the velocity ratios and E/A ratio at the tricuspid orifice in the two groups were analysed,and the correlation between the ventricular late diastolic velocity/ventricular diastolic peak flow velocity and E/A ratios was the best(R^2of the isolated SUA group:0.520;R2 of the control group:0.358).The correlations between the velocity ratios and tissue Doppler Tei index of foetal right ventricular in the two groups were analysed,and the correlation between the pulsatility index for veins(PIV)and tissue Doppler Tei index ratios was the best(R2 of the isolated SUA group:0.865;R2 of the control group:0.627).CONCLUSION In the isolated SUA group,the atrial systolic peak velocity‘a’decreased,and this finding might be related to the changes in foetal cardiac *** ratio of ventricular late diastolic velocity to ventricular diastolic peak flow

关键词： Isolated single umbilical artery Ductus venosus Velocity Right ventricular diastolic function Foetus

Dynamic and static performance optimization of dual active bridge DC-DC converters

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Journal of Modern Power Systems and Clean Energy 2018年第3期6卷 607-618页

作者： nie HOU Wensheng SONG Yutong ZHU xiao SUN Wei LI School of Electrical Engineering Southwest Jiaotong University Locomotive & Car Research Institute China Academy of Railway Sciences

High efficiency and fast dynamic response are two main control objectives for dual active bridge(DAB)DC-DC converters. Traditional extended phase shift(EPS)control can significantly enhance the conversion efficiency of DAB DC-DC converters by reducing current stress;however, it cannot fulfill fast dynamic response requirements. In this paper, a novel hybrid control scheme consisting of EPS control and direct power control(DPC),named as EPS-DPC, is proposed. EPS-DPC control has salient features in both efficiency and dynamic performance. In order to verify the outstanding performance of the proposed EPS-DPC scheme, an experimental comparison was carried out on a scale-down DAB DC-DC converter among several control strategies, including single phase shift control with traditional voltage-loop(SPS-TVL), EPS control with traditional voltage-loop(EPSVTL), and EPS-DPC. Experimental results have been high consistent with theoretical analysis, and verified these advantages of the proposed EPS-DPC scheme.

关键词： Current stress Efficiency Dynamic response Dual active bridge(DAB) DC-DC converter Extended phase shift control Direct power control

Recent Research on the Deformation Behavior of Particle Reinforced Magnesium Matrix Composite: A Review

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Acta Metallurgica Sinica(English Letters) 2019年第4期32卷 413-425页

作者： Kun-Kun Deng Cui-Ju Wang Kai-Bo nie xiao-Jun Wang Shanxi Key Laboratory of Advanced Magnesium-Based Materials College of Materials Science and Engineering Taiyuan University of Technology School of Materials Science and Engineering Harbin Institute of Technology

Particle reinforced magnesium matrix composite(PMMC) possesses the merits of high specific strength, high specific modulus, better dimensional stability, good wear resistance and lower production cost, which is thought as a promising material in the field of aerospace, automobile, electronic communication, etc. To eliminate the casting defect, the PMMC is usually experienced hot deformation process. The present paper mainly focuses on the deformation behavior of PMMCs. First, the development of PMMCs based on particle size is introduced. Then, the hot deformation technology and deformation mechanism of PMMCs at elevated temperature are given and analyzed, respectively. After reviewing the dynamic recrystallization and texture of PMMCs, its future development is suggested based on the current research progress.

关键词： Magnesium matrix composite Particle Hot deformation Deformation mechanism Recrystallization

Radial solution of the Logarithmic Laplacian system

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 114-124页

作者： ZHANG Li-hong nie xiao-feng WANG Guo-tao Bashir Ahmad School of Mathematics and Computer Science Shanxi Normal UniversityLinfen 041004China Nonlinear Analysis and Applied Mathematics(NAAM)Research Group Department of MathematicsFaculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia.

The paper generalizes the direct method of moving planes to the Logarithmic Laplacian ***,some key ingredients of the method are discussed,for example,Narrow region principle and Decay at ***,the radial symmetry of th... 详细信息

关键词： the Logarithmic Laplacian system radial symmetry the direct method of moving planes