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Learning multi-tasks with inconsistent labels by using auxiliary big task

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Frontiers of Computer Science 2023年第5期17卷 119-132页

作者： quan feng Songcan CHEN College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China MIIT Key Laboratory of Pattern Analysis and Machine Intelligence Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Multi-task learning is to improve the performance of the model by transferring and exploiting common knowledge among *** MTL works mainly focus on the scenario where label sets among multiple tasks(MTs)are usually the same,thus they can be utilized for learning across the ***,the real world has more general scenarios in which each task has only a small number of training samples and their label sets are just partially overlapped or even *** such MTs is more challenging because of less correlation information available among these *** this,we propose a framework to learn these tasks by jointly leveraging both abundant information from a learnt auxiliary big task with sufficiently many classes to cover those of all these tasks and the information shared among those partiallyoverlapped *** our implementation of using the same neural network architecture of the learnt auxiliary task to learn individual tasks,the key idea is to utilize available label information to adaptively prune the hidden layer neurons of the auxiliary network to construct corresponding network for each task,while accompanying a joint learning across individual *** experimental results demonstrate that our proposed method is significantly competitive compared to state-of-the-art methods.

关键词： multi-task learning inconsistent labels auxiliary task

Towards a quantum network

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National Science Review 2017年第2期4卷 168-169页

作者： Jian-Shun Tang Zong-quan zhou Chuan-feng Li Key Laboratory of quantum Information University of Science and Technology of China Synergetic Innovation Center of quantum Information & quantum Physics University of Science and Technology of China

A quantum network is believed to be the next generation of quantum technology[1].In the past decades,individual quantum systems—for example,quantum dot(QD)[2–4],etc.—have been studied in depth and the technologies ... 详细信息

关键词： QKD net QDs

Phase transformation and thermal analysis during combustion synthesis of Mg_(17)Al_(12) alloy

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Rare Metals 2014年第1期33卷 37-40页

作者： Yu-Li zhou Yun Lu Yun-feng Zhu Li-quan Li College of Materials Science and Engineering Nanjing University of Technology

The Mg-A1 hydrogen storage alloy was suc- cessfully prepared by combustion synthesis （CS） method. The formation of alloy phases during the CS process was studied using X-ray diffraction （XRD）, scanning electron microscope （SEM）, and differential scanning calorimetry （DSC）. When the time increases from 0, 0.5, 1.0 to 2.0 h at 733 K, the products are Mg and A1; Mg2A13, Mg and A1; Mgl7All2, Mg2A13; and Mg; and eventually only MgI7A112, respectively. Combined with three peaks in the DSC traces, it is concluded that the formation of MglyAll2 during the CS includes three processes, namely, the formation of MgzA13 first; then the unsaturated solid solution, MglvAla2; and finally the complete MglvA112 alloy. The formation of MgzA13 prior to MglvA112 in this work is different from those prepared by mechanical alloying. This is thought to be related to the instant high temperature during the ther- mal explosion of CS.

关键词： Mg-A1 alloy Combustion synthesis Phasetransformation Thermal analysis

Flow structures of turbulent Rayleigh-Benard convection in annular cells with aspect ratio one and larger

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Acta Mechanica Sinica 2021年第8期37卷 1291-1298,I0002页

作者： Xu Zhu quan zhou Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai200072China

We present an experimental study of flow structures in turbulent Rayleigh-Bénard convection in annular cells of aspect ratiosΓ=1,2 and 4,and radius ratio *** convecting fluid is water with Prandtl number Pr=4.3 and *** number Ra ranges 4.8×10^(7)≤Ra≤4.5×10^(10).The dipole state(two-roll flow structure)forΓ=1 and the quadrupole state(fourroll flow structure)forΓ=2 and 4 are found by multi-temperature-probe *** number Nu is described by a power-law scaling Nu=0.11Ra^(0.31),which is insensitive to the change of flow ***,the Reynolds number Re is influenced by increasing aspect ratios,where Re is found to scale with Ra andΓas Re~Ra^(0.46)Γ^(-0.52).The normalized amplitudes of two flow structures as a function of Ra exist *** on relative weights of the first four modes using the Fourier analysis,we find that the first mode dominates inΓ=1 cell,but the second mode contains the most energy inΓ=2 and 4 *** increasingΓ,the flow structures exhibit different characteristics.

关键词： Rayleigh–Bénard convection Turbulence Annular convection

Supermassive black holes triggered by QCD axion bubbles

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Communications in Theoretical Physics 2024年第5期76卷 134-139页

作者： Hai-Jun Li Ying-quan Peng Wei Chao Yu-feng zhou Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Center for Advanced quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Beijing/HangzhouChina

Supermassive black holes(SMBHs)are ubiquitous in the center of galaxies,although the origin of their massive seeds is still *** this paper,we investigate the formation of SMBHs from the quantum chromodynamics(QCD)axion *** this case,primordial black holes(PBHs)are considered as the seeds of SMBHs,which are generated from the QCD axion bubbles due to an explicit Peccei–Quinn(PQ)symmetry breaking after *** QCD axion bubbles are formed when the QCD axion starts to oscillate during the QCD phase *** consider a general case in which the axion bubbles are formed with the bubble effective angle θ_(eff)∈(0,π],leading to the minimum PBH mass∼■(10^(4)−10^(7))M⊙for the axion decay constant f_(a)∼■(10^(16))*** PBHs at this mass region may account for the seeds of SMBHs.

关键词： supermassive black holes primordial black holes quantum chromodynamics axion

Column envelope meshing pair and its design method for single screw compressors

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第1期10卷 31-36页

作者： Wei-feng WU quan-ke feng School of Energy and Power Engineering Xi 'an Jiaotong University Xi 'an 710049 China

A single screw compressor (SSC) is an important component found in many refrigeration ***,the durability is not so good because of the friction between its meshing *** the column envelope meshing pair was pro-posed to prolong the operating life of SSCs,although it has not been applied to commercial refrigeration *** accelerate the industrial application,a mathematical model for analyzing the column envelope meshing pair is established based on the geometry and *** giving the flanks of column envelope grooves are obtained,and teeth flank meshing with the groove is *** show that this model could be applicable in the design of the column envelope type SSC.

关键词： Column envelope Single screw compressor (SSC) Meshing pair design Mathematical model

Effects of GLUT4 expression on insulin resistance in patients with advanced liver cirrhosis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第8期12卷 677-682页

作者： Wei-feng SHAN Bing-quan CHEN Shao-jun ZHU Li JIANG Yan-feng zhou Department of Anesthesiology the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Decreased glucose tolerance and diabetes are frequently observed in advanced liver cirrhosis patients and may be related to insulin *** transporter-4 (GLUT4),one of the most important glucose transporters,plays a key role in the development of type 2 *** order to study the mechanism of insulin resistance in liver cirrhosis patients,we measured the insulin sensitivity index and determined the GLUT4 protein and mRNA contents of skeletal muscle by Western blotting and reverse transcription-polymerase chain reaction (RT-PCR),respectively,in normal people and liver cirrhosis *** results showed that the levels of glucose,insulin,and C-peptide in two liver cirrhosis groups were higher and the insulin sensitivity index lower than those of the normal control *** sensitivity of insulin may decrease with the decline of liver ***,the contents of GLUT4 protein and mRNA in patients with advanced liver cirrhosis were similar to those of normal *** conclusion,insulin resistance is observed in patients with advanced liver cirrhosis but may not be correlated with the skeletal contents of GLUT4 protein and mRNA.

关键词： Glucose transporter-4 (GLUT4) Liver cirrhosis Insulin resistance Skeletal muscle

BUCKLING ANALYSIS OF STRETCHABLE FERROELECTRIC THIN FILM ON ELASTOMERIC SUBSTRATES

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Acta Mechanica Solida Sinica 2014年第5期27卷 509-517页

作者： Zhidong zhou quan Jiang Department of Materials Science and Engineering College of MaterialsXiamen University College of Civil Engineering Nantong University

The thin stiff films on pre-stretched compliant substrates can form wrinkles, which can be controlled in micro and nanoscale systems to generate smart structures. Recently, buck- led piezoelectric/ferroelectrie nanoribbons have been reported to show an enhancement in the piezoelectric effect and stretchability, which can be applied in energy harvesting devices, sensors and memory devices instead of polymeric polyvinylidine fluoride （PVDF）. This paper studies the buckling and post-buckling process of ferroelectric thin films bonded to the pre-stretched soft layer, which in turn lies on a rigid support. Nonlinear electromechanical equations for the buckling of thin piezoelectric plates are deduced and employed to model the ferroelectric film poled in the thickness direction. Two buckling modes are analyzed and discussed： partially de-adhered buck- ling and fully adhered buckling. Transition from one buckling mode to the other is predicted and the effect of piezoelectricity on the critical buckling condition of piezoelectric film is examined.

关键词： buckling ferroelectric films energy method variational method

Nonlinear autopilot design for interceptors with tail fins and pulse thrusters via θ–D approach

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Journal of Systems Engineering and Electronics 2014年第2期25卷 273-280页

作者： quan Li Di zhou School of Astronautics Harbin Institute of Technology

The missile autopilot for an interceptor with tail fins and pulse thrusters is designed via the θ-D approach. The nonlin- ear dynamic model of the pitch and yaw motion of the missile is transformed into a linear-like structure with state-dependent coef- ficient （SDC） matrices. Based on the linear-like structure, a θ-D feedback controller is designed to steer the missile to track refer- ence acceleration commands. A sufficient condition that ensures the asymptotic stability of the tracking system is given based on Lyapunov＇s theorem. Numerical results show that the proposed autopilot achieves good tracking performance and the closed-loop tracking system is asymptotically stable.

关键词： blended control nonlinear control suboptimal control,θ-D approach.