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Re-Distributing Facial Features for Engagement Prediction with ModernTCN

Computers, Materials & Continua 2024年第10期81卷 369-391页

作者： xi Li Weiwei Zhu Qian Li Changhui hou Yaozong Zhang College of Information and Artificial Intelligence Nanchang Institute of Science and TechnologyNanchang330108China School of Electrical and Information Engineering Wuhan Institute of TechnologyWuhan430205China School of Electronic Information Engineering Wuhan Donghu UniversityWuhan430212China

Automatically detecting learners’engagement levels helps to develop more effective online teaching and assessment programs,allowing teachers to provide timely feedback and make personalized adjustments based on students’needs to enhance teaching *** approaches mainly rely on single-frame multimodal facial spatial information,neglecting temporal emotional and behavioural features,with accuracy affected by significant pose ***,convolutional padding can erode feature maps,affecting feature extraction’s representational *** address these issues,we propose a hybrid neural network architecture,the redistributing facial features and temporal convolutional network(RefEIP).This network consists of three key components:first,utilizing the spatial attention mechanism large kernel attention(LKA)to automatically capture local patches and mitigate the effects of pose variations;second,employing the feature organization and weight distribution(FOWD)module to redistribute feature weights and eliminate the impact of white features and enhancing representation in facial feature ***,we analyse the temporal changes in video frames through the modern temporal convolutional network(ModernTCN)module to detect engagement *** constructed a near-infrared engagement video dataset(NEVD)to better validate the efficiency of the RefEIP *** extensive experiments and in-depth studies,we evaluated these methods on the NEVD and the Database for Affect in Situations of Elicitation(DAiSEE),achieving an accuracy of 90.8%on NEVD and 61.2%on DAiSEE in the fourclass classification task,indicating significant advantages in addressing engagement video analysis problems.

关键词： Engagement prediction spatiotemporal network re-distributing facial features temporal convolutional network

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Application of two special orbits in the orbit determination of lunar satellites

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Research in Astronomy and Astrophysics 2014年第10期14卷 1307-1328页

作者： Peng Liu xi-Yun hou Jing-Shi Tang Lin Liu School of Astronomy and Space Science Nanjing University Institute of Space Environment and Astrodynamics Nanjing University

Using inter-satellite range data, the combined autonomous orbit determina- tion problem of a lunar satellite and a probe on some special orbits is studied in this paper. The problem is firstly studied in the circular restricted three-body problem, and then generalized to the real force model of the Earth-Moon system. Two kinds of spe- cial orbits are discussed： collinear libration point orbits and distant retrograde orbits. Studies show that the orbit determination accuracy in both cases can reach that of the observations. Some important properties of the system are carefully studied. These findings should be useful in the future engineering implementation of this conceptual study.

关键词： celestial mechanics -- space vehicles -- Moon -- methods numerical

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Fast Smooth Second-Order Sliding Mode Control with Disturbance Observer for Automatic Shell Magazine

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Journal of Shanghai Jiaotong university(Science) 2021年第6期26卷 847-856页

作者： YAO Laipeng hou Baolin LIU xi School of Mechanical Engineering Changshu Institute of TechnologySuzhou 215500JiangsuChina School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China

This paper studies practical control design for a novel automatic shell magazine(ASM)with a new fast smooth second-order sliding mode(FSSOSM)control based on disturbance *** dynamic model of the ASM with parameter perturbations and nonlinear friction is established.A higher order sliding mode disturbance observer based on super-twisting algorithm is utilized as a robust compensator to estimate the lumped *** proposed FSSOSM control is performed to obtain the continuous sliding mode control law and inhibit the chattering *** finite time convergence is investigated by utilizing the Lyapunov stability *** controllers,the traditional sliding mode controller,the proposed FSSOSM controller and a continuous fixed-time second-order sliding mode(CFTSOSM)controller,are *** comparative simulation results under three typical working conditions(no-loaded,half-loaded and full-loaded)demonstrate that the proposed control strategy has a high dynamic tracking performance along with a good robustness against model uncertainty.

关键词： nonlinear systems model uncertainty disturbance observer finite-time convergence sliding mode control

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Neuropeptide Y and melanocortin receptors in fish:regulators of energy homeostasis

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Marine Life Science & Technology 2022年第1期4卷 42-51页

作者： Zhi-Shuai hou Hai-Shen wen Key Laboratory of Mariculture(Ocean University of China) Ministry of Education(KLMME)Fisheries CollegeOcean University of ChinaQingdao266003China

Energy homeostasis,which refers to the physiological processes that the energy intake is exquisitely coordinated with energy expenditure,is critical for ***,multiple and complex mechanisms have been involved in the regulation of energy *** central melanocortin system plays an important role in modulating energy *** system includes the orexigenic neurons,expressing neuropeptide Y/Agouti-related protein(NPY/AgRP),and the anorexigenic neurons expressing proopiomelanocortin(POMC).The downstream receptors of NPY,AgRP and post-translational products of POMC are G protein-coupled receptors(GPCRs).This review summarizes the compelling evidence demonstrating that NPY and melanocortin receptors are involved in energy ***,the comparative studies on physiology and pharmacology of NPY and melanocortin receptors in humans,rodents and teleosts are ***,we provide a strategy demonstrating the potential application of the new ligands and/or specific variants of melanocortin system in aquaculture.

关键词： Energy homeostasis Neuropeptide Y receptors Melanocortin receptors GPCRs Fish(Teleost)

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Numerical Simulation and Experimental Study of the Stress Formation Mechanism of FDM with Different Printing Paths

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Journal of Renewable Materials 2023年第1期11卷 273-289页

作者： Heping hou Yang Yue Jian Liu Darun xi Shanhui Liu Faculty of Printing Packaging Engineering and Digital Media TechnologyXi’an University of TechnologyXi’an710000China Shaanxi Beiren Printing Machinery Co. Ltd.Weinan714000China

Environmental contamination has been caused by petroleum-based polymeric materials in the melt deposition *** biodegradable materials have been widely used in the fused deposition modeling(FDM)industry,such as polylactic acid(PLA).However,internal complex thermal stress and deformations in part caused by an uneven distribution of PLA filament deposition temperatures during FDM,which will seriously affect the geometric accuracy of the printed *** order to reduce material waste and environmental pollution during the printing process,the accuracy of PLA part can be ***,numerical simulation was carried out to investigate the temperature field and stress field during the building and cooling process of cuboid *** effects of printing path on the thermal stress and temperature field during the building process were mainly *** results show that the printing path has a significant effect on the stress *** most uni-form stress distribution and the smallest deformation were obtained using the Zig Zag printing ***,the residual stress during the cooling process was collected using strain gauges embedded at the mid-plane of the FDM built cuboid *** simulation results are consistent with the experimental results.

关键词： Fused deposition molding numerical simulation strain gauges stress measurement

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Symplectic analysis for elastic wave propagation in two-dimensional cellular structures

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Acta Mechanica Sinica 2010年第5期26卷 711-720页

作者： xiu-Hui hou Zi-Chen Deng Jia-xi Zhou Tie-Quan Liu Department of Engineering Mechanics Northwestern Polytechnical University Xi'an 710072 China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China

On the basis of the finite element analysis, the elastic wave propagation in cellular structures is investigated using the symplectic algorithm. The variation principle is first applied to obtain the dual variables and the wave propagation problem is then transformed into two-dimensional （2D） symplectic eigenvalue problems, where the extended Wittrick-Williams algorithm is used to ensure that no phase propagation eigenvalues are missed during computation. Three typical cellular structures, square, triangle and hexagon, are introduced to illustrate the unique feature of the symplectic algorithm in higher-frequency calculation, which is due to the conserved properties of the structure-preserving symplectic algorithm. On the basis of the dispersion relations and phase constant surface analysis, the band structure is shown to be insensitive to the material type at lower frequencies, however, much more related at higher frequencies. This paper also demonstrates how the boundary conditions adopted in the finite element modeling process and the structures＇ configurations affect the band structures. The hexagonal cells are demonstrated to be more efficient for sound insulation at higher frequencies, while the triangular cells are preferred at lower frequencies. No complete band gaps are observed for the square cells with fixed-end boundary conditions. The analysis of phase constant surfaces guides the design of 2D cellular structures where waves at certain frequencies do not propagate in specified directions. The findings from the present study will provide invaluable guidelines for the future application of cellular structures in sound insulation.

关键词： Cellular structures Symplectic analysis Dispersion relation - Phase constant surface Sound insulation

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Controlling reversible complexation-mediated polymerization(RCMP)via deep eutectic solvents:fast kinetics,narrow molecular weight distribution and mechanistic insights

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Science China Chemistry 2024年第8期67卷 2728-2736页

作者： xin Fu Zhen Lu Shen Li Zheng-Hong Luo Lin-xi hou Department of Materials-Oriented Chemical Engineering College of Chemical EngineeringFuzhou UniversityFuzhou 350116China Department of Chemical Engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200030China Chemical Engineering Zhicheng College of Fuzhou UniversityFuzhou 350116China Qingyuan Innovation Laboratory Quanzhou 362801China

The exploitation of new green polymerization avenues for the effective synthesis of polymers by reversible-deactivation radical polymerization plays a critical role in pursuing the development of polymeric *** this work,serials of deep eutectic solvents(DES)with intermolecular-hydrogen-bonding interaction were constructed as catalysts and medium for actuating reversible complexation-mediated polymerization(RCMP)for the first time,yielding methacrylate polymers with high monomer conversion and narrow dispersion molecular weight in both water and oil *** mechanism and elementary reaction of RCMP were explored deeply,revealing that the complexation of initiator with DES to generate radicals was a ratecontrolling step and intermolecular-hydrogen-bond was primary factor to influence polymerization ***,the insights of density functional theory calculations revealed that negative electrostatic potential ensured nucleophilic *** investigation demonstrated the considerable potential of DES for RCMP,which is anticipated for other polymerization applications as a novel medium mode.

关键词： deep eutectic solvent reversible complexation-mediated polymerization intermolecular hydrogen bonding density functional theory elementary reaction steps

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Photoluminescent nickel(Ⅱ)carbene complexes with ligand-to-ligand charge-transfer excited states

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Chinese Chemical Letters 2024年第1期35卷 357-360页

作者： Chun-Liang hou Jia-xi Song xiaoyong Chang Yong Chen Key Laboratory of Photochemical Conversion and Optoelectronic Materials&CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China

While nickel(II)complexes have been widely used as catalysts for carbon-carbon coupling reactions,the exploration of their photophysical and photochemical properties is still in the ***,a series of square-planar Ni(II)complexes[(diNHC)NiX2]bearing chelating benzimidazole-based bis(N-heterocyclic carbene)ligands and varying anionic coligands(1,X=Cl;2,X=Br;3,X=I)are synthesized and structurally *** solid state,both 1 and 2 exhibit orange-red photoluminescence under ambient *** photophysical and electrochemical measurements along with density functional theory(DFT)calculations reveal that the low-energy emissions can be attributed to singlet excited states with ligand-to-ligand charge-transfer(LLCT)*** work suggests that strong-field N-heterocyclic carbene ligands play a crucial role to achieve the luminescence of Ni(II)complexes.

关键词： Nickel(II)complexes N-Heterocyclic carbene Luminescence Ligand-to-ligand charge-transfer character Low-lying d-d excited states

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Equivalent Characterization of Centralizers on B(H)

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Acta Mathematica Sinica,English Series 2016年第9期32卷 1113-1120页

作者： wen Si XU Run Ling AN Jin Chuan hou Department of Mathematics Taiyuan University of Technology Taiyuan 030024 P. R. China

Let H be a Hilbert space with dimH ≥2 and Z ∈ B（H） be an arbitrary but fixed operator. In this paper we show that an additive map （I）： B（H）→ B（H） satisfies Ф（AB） = Ф（A）B = AФ（B） for any A, B ∈ B（H） with AB = Z if and only if Ф（AB） = Ф（A）B = AФ（B）, A, B ∈ B（H）, that is, （I） is a centralizer. Similar results are obtained for Hilbert space nest algebras. In addition, we show that Ф（A2） = AФ（A） = Ф（A）A for any A ∈ B（H） with A2 = 0 if and only if Ф（A） = AФ（I） = Ф（I）A, A ∈ B（H）, and generalize main results in Linear Algebra and its Application, 450, 243-249 （2014） to infinite dimensional case. New equivalent characterization of centralizers on B（H） is obtained.

关键词： Centralizers full-centralized points von Neumann algebras nest algebras

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Maps Preserving Peripheral Spectrum of Generalized Jordan Products of Operators

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Acta Mathematica Sinica,English Series 2015年第6期31卷 953-972页

作者： wen ZHANG Jin Chuan hou xiao Fei QI Department of Mathematics Shanxi University Department of Mathematics University of TechnologyTaiyuan

Let X1 and X2 be complex Banach spaces with dimension at least three, A1 and A2 be standard operator algebras on X1 and X2, respectively. For k ≥ 2, let （i1, i2, . . . , im） be a finite sequence such that {i1, i2, . . . , im} = {1, 2, . . . , k} and assume that at least one of the terms in （i1, . . . , im） appears exactly once. Define the generalized Jordan productT1 o T2 o··· o Tk = Ti1Ti2··· Tim ＋ Tim··· Ti2Ti1 on elements in Ai. This includes the usual Jordan product A1A2 ＋ A2A1, and the Jordan triple A1A2A3 ＋ A3A2A1. Let Φ ： A1 → A2 be a map with range containing all operators of rank at most three. It is shown that Φ satisfies that σπ（Φ（A1） o··· o Φ（Ak）） = σπ（A1 o··· o Ak） for all A1, . . . , Ak, where σπ（A） stands for the peripheral spectrum of A, if and only if Φ is a Jordan isomorphism multiplied by an m-th root of unity.

关键词： Peripheral spectrum generalized Jordan products Banach spaces standard operatoralgebras

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