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Science in China(Series F) 2009年第12期52卷 2450-2458页

作者： WANG Ping LI YingZhe SUN Kun GOU tianhang Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China Graduate University of Chinese Academy of Sciences Beijing 100039 China

For the IMT-advanced broadband mobile communication systems, an accurate broadband channel model is significant to the system design. However, the broadband channel impulse response （CIR） becomes sensitive to the complex propagation impacts of both specular path and diffuse dense path in a rich-scattering environment. We propose a cross-estimation （CE）-based channel modeling method by which the dense diffusion components can be identified independently and separated successfully from the overall ClR. As a result, the parameter estimation accuracy can be obviously improved, regardless of the complex diffusion impact in a rich scattering environment. Both theoretical derivation and experimental results are given to validate it based on the typical broadband channel measurement with 100 MHz bandwidth at 2.6 GHz in an urban hotspot scenario in Shanghai.

关键词： cross-estimation channel model channel measurement channel impulse response IMT-advanced mobile communication

Controllable thermal rectification design for buildings based on phase change composites

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Journal of Semiconductors 2024年第2期45卷 40-45页

作者： Hengbin Ding Xiaoshi Li tianhang Li Xiaoyong Zhao He Tian School of Integrated Circuits and Beijing National Research Center for Information Science and Technology(BNRist) Tsinghua UniversityBeijing 100084China Zhuhai Huafa Properties Co. LtdZhuhai 519030China

Phase-change material(PCM)is widely used in thermal management due to their unique thermal ***,related research in thermal rectifier is mainly focused on exploring the principles at the fundamental device level,which results in a gap to real ***,we propose a controllable thermal rectification design towards building applications through the direct adhesion of composite thermal rectification material(TRM)based on PCM and reduced graphene oxide(rGO)aerogel to ordinary concrete walls(CWs).The design is evaluated in detail by combining experiments and finite element *** is found that,TRM can regulate the temperature difference on both sides of the TRM/CWs system by thermal *** difference in two directions reaches to 13.8 K at the heat flow of 80 W/m^(2).In addition,the larger the change of thermal conductivity before and after phase change of TRM is,the more effective it is for regulating temperature difference in two *** stated technology has a wide range of applications for the thermal energy control in buildings with specific temperature requirements.

关键词： phase change composites controllable thermal rectification building applications

光照治疗在职业人群精神心理健康领域应用的理论基础及应用现状

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照明工程学报 2023年第4期34卷 5-9页

作者：周天航周书喆吕柯党卫民曲丽娜陈志忠董问天聂靖昕唐彦杨磊于欣北京大学第六医院北京100191 北京大学精神卫生研究所北京100191 国家卫生健康委员会精神卫生学重点实验室(北京大学) 北京100191 国家精神心理疾病临床医学研究中心(北京大学第六医院) 北京100191 中国航天员科研训练中心航天医学全国重点实验室北京100094 北京大学物理学院北京100871 北京大学长三角光电研究院江苏南通226000 北京大学东莞光电研究院广东东莞523808 北京大学体育教研部北京100871

光照治疗作为一种安全的物理治疗方法,已在精神卫生领域得到应用,并已被相关研究证实可有效改善抑郁情绪、睡眠障碍及认知功能。目前,光照治疗在职业卫生领域的应用仍处于起步阶段,相关研究报道较少。本文旨在对光照治疗的作用机制及其... 详细信息

光照治疗作为一种安全的物理治疗方法,已在精神卫生领域得到应用,并已被相关研究证实可有效改善抑郁情绪、睡眠障碍及认知功能。目前,光照治疗在职业卫生领域的应用仍处于起步阶段,相关研究报道较少。本文旨在对光照治疗的作用机制及其在精神卫生及职业卫生领域的应用现状进行总结,以期为促进职业人群的精神心理健康提供参考。

关键词：光照治疗职业人群心理健康

Predicting transformer temperature field based on physics-informed neural networks

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High Voltage 2024年第4期9卷 839-852页

作者： Pengfei Tang Zhonghao Zhang Jie Tong tianhang Long Can Huang Zihao Qi China Electric Power Research Institute BeijingChina

The safe operation of oil-immersed transformers is critical to the safety and stability of the power *** the operating time increases,the failure rate of oil-immersed transformers shows an increasing trend,posing serious challenges to safe *** is necessary to investigate the internal state of the oil-immersed transformer to improve the digital degree and achieve digitalisation and intelligent operation and maintenance.A physics-informed neural network(PINN)for oil-immersed transformers was introduced to reconstruct the temperature distribution inside the *** to the approach,the loss function of the network would be optimised by incorporating physical constraint loss terms including heat transfer equations,initial conditions and boundary *** results show that the method proposed can be used to reconstruct and predict the temperature field of transformers in a few seconds with satisfactory *** conclusion,the PINN proposed outperforms deep neural networks in terms of accuracy,reliability and interpretability,especially in data-poor cases.

关键词： immersed conclusion constraint

The colorful chemistry of nanoscale zero-valent iron(nZVI)

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Journal of Environmental Sciences 2018年第5期30卷 1-3页

作者： Yilong Hua Jing Liu tianhang Gu Wei Wang Wei-xian Zhang State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and Engineering Tongji University School of Chemical Science and Engineering Tongji University

Nanoscale zero-valent iron （nZVI） possesses unique chemistry and capability for the separation and transformation of a growing number of environmental contaminants. A nZVI particle consists of two nanoscale components, an iron （oxyhydr）oxides shell and a metallic iron core. This classical ＂core-shell＂ structure offers nZVI with unique and multifaceted reactivity of sorption, complexation, reduction and precipita- tion due to its strong small particle size for engineering deployment, large surface area, abundant reactive sites and electron-donating capacity for enhanced chemical activity. For over two decades, research has been steadily expanding our understanding on the reaction mechanisms and engineering performance of nZVI for soil and groundwater remediation, and more recently for wastewater treatment.

关键词： Nanoscale zero-valent iron (nZVI) Environmental nanotechnology Dyes and pigments Wastewater treatment Spherical aberration-corrected scan-ning transmission electron micros-copy (Cs-STEM)

A Rapid Analysis Tool for Aerodynamics/Aerothermodynamics of Hypersonic Vehicles

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第4期34卷 398-404页

作者： Li Zhengzhou Xiao tianhang Lü Fanxi Yu Xiongqing Zhang Zhenming Du Sha College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Shanghai Institute of Mechanical and Electrical Engineering

A rapid engineering surface panel method to analyze aerodynamics and aerothermodynamics of hypersonic vehicles is *** obtain the surface pressure distribution of a hypersonic vehicle,the local surface inclination method is applied to calculate the pressure coefficient for each surface panel element,of which the normal vector is corrected first by using an efficient data structure and Rey-casting algorithm,local Reynolds numbers are calculated according to the geometric streamline method,then the aerodynamic heating flux is computed by both reference enthalpy relations and Reynolds analogy *** typical test cases are performed and the results indicate that,the developed tool is effective in predicting the aerodynamics/aerothermodynamics for complex geometry of hypersonic vehicle in a wide range of Mach numbers with a sufficient accuracy.

关键词： hypersonic aerodynamics aerothermodynamics engineering prediction reference enthalpy relation Reynolds analogy

Phonon dispersion relations of crystalline solids based on LAMMPS package

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Chinese Physics B 2021年第11期30卷 395-400页

作者： Zhiyong Wei tianhang Qi Weiyu Chen Yunfei Chen Jiangsu Key Laboratory for Design&Manufacture of Micro/Nano Biomedical Instruments and School of Mechanical Engineering Southeast UniversityNanjing 211189China College of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing 210037China

The phonon dispersion relations of crystalline solids play an important role in determining the mechanical and thermal properties of *** phonon dispersion relation,as well as the vibrational density of states,is also often used as an indicator of variation of lattice thermal conductivity with the external stress,defects,*** this study,a simple and fast tool is proposed to acquire the phonon dispersion relation of crystalline solids based on the LAMMPS *** theoretical details for the calculation of the phonon dispersion relation are derived mathematically and the computational flow chart is *** tool is first used to calculate the phonon dispersion relation of graphene with two atoms in the unit ***,the phonon dispersions corresponding to several potentials or force fields,which are commonly used in the LAMMPS package to modeling the graphene,are obtained to compare with that from the DFT *** are further extended to evaluate the accuracy of the used potentials before the molecular dynamics *** tool is also used to calculate the phonon dispersion relation of superlattice structures that contains more than one hundred of atoms in the unit cell,which predicts the phonon band gaps along the cross-plane *** the phonon dispersion relation plays an important role in the physical properties of condensed matter,the proposed tool for the calculation of the phonon dispersion relation is of great significance for predicting and explaining the mechanical and thermal properties of crystalline solids.

关键词： phonon dispersion relation molecular dynamics force constant potential function

Simultaneous acceleration of sulfur reduction and oxidation on bifunctional electrocatalytic electrodes for quasi-solid-state Zn–S batteries

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Science China Chemistry 2024年第5期67卷 1531-1538页

作者： Mingli Wang Hong Zhang tianhang Ding Fangjun Wu Lin Fu Bin Song Pengfei Cao Ke Lu Institutes of Physical Science and Information Technology School of Materials Science and EngineeringKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei 230601China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001China School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123China State Key Lab of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China

The incomplete sulfur reduction and high ZnS re-oxidation energy barrier along with severe side reactions during the battery cycling compromise the practical application of Zn–S electrochemistry. Herein, a bifunctional electrocatalytic sulfur matrix that simultaneously accelerates the sulfur reduction and ZnS oxidation is proposed to realize a highly-efficient Zn–S cell. It is revealed that the N-heteroatom hotspots are more favorable for facilitating the conversion of S to ZnS while the CoO nanocrystal substantially lowers the ZnS activation energy barrier thereby suppressing the formation of disproportionation species(e.g.,SO_(4)^(2-)) and accumulation of inactive ZnS. Accordingly, the Co O anchored on the N-doped carbon-supported sulfur cathode delivers a high Zn^(2+)storage capacity of 1,172 m Ahg^(-1)and outstanding cycling stability with a capacity retention of 71.6% after500 cycles with a high average Coulombic efficiency of 97.8%. Simultaneously, the stable cycling of solid-state Zn–S pouch cells with an energy density of 585 Whkg^(-1)sulfuris also demonstrated. Moreover, the postmortem analysis reveals that the degradation of Zn–S cells is mainly attributed to the limited reversibility of Zn anodes rather than the ZnS decomposition and/or accumulation. The approach to the bidirectional catalysis manipulated the sulfur redox provides a new perspective to realize the theoretical potentials of Zn–S cells.

关键词： Zn–S battery bifunctional catalysts solid-state battery sulfur redox degradation mechanism

Toward Improved Accuracy in Quasi-Static Elastography Using Deep Learning

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 911-935页

作者： Yue Mei Jianwei Deng Dongmei Zhao Changjiang Xiao tianhang Wang Li Dong Xuefeng Zhu Department of Engineering Mechanics State Key Laboratory of Structural Analysis for Industrial EquipmentDalian University of TechnologyDalian116023China International Research Center for Computational Mechanics Dalian University of TechnologyDalian116023China DUT-BSU Joint Institute Dalian University of TechnologyDalian116023China Department of Automotive Engineering Tongji UniversityShanghai201804China *** SeattleWA98109USA School of Automotive Engineering Dalian University of TechnologyDalian116023China

Elastography is a non-invasive medical imaging technique to map the spatial variation of elastic properties of soft *** quality of reconstruction results in elastography is highly sensitive to the noise induced by imaging measurements and *** address this issue,we propose a deep learning(DL)model based on conditional Generative Adversarial Networks(cGANs)to improve the quality of nonhomogeneous shear modulus *** train this model,we generated a synthetic displacement field with finite element simulation under known nonhomogeneous shear modulus *** the simulated and experimental displacement fields are used to validate the proposed *** reconstructed results demonstrate that the DL model with synthetic training data is able to improve the quality of the reconstruction compared with the well-established optimization ***,we emphasize that our DL model is only trained on synthetic *** might provide a way to alleviate the challenge of obtaining clinical or experimental data in ***,this work addresses several fatal issues in applying the DL technique into elastography,and the proposed method has shown great potential in improving the accuracy of the disease diagnosis in clinical medicine.

关键词： Nonhomogeneous elastic property distribution reconstruction deep learning finite element method inverse problem elastography conditional generative adversarial network

精神障碍患者未成年子女与父母的亲子沟通及相关因素

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中国心理卫生杂志 2023年第6期37卷 449-457页

作者：陈冰冰陈蔚然杜春雨周天航洪旭吴素英文丽萍朱灵艳杨先梅唐琦张涛刘文卉张长春潘杨许俊亭张宇楠马弘于欣管丽丽北京大学第六医院北京大学精神卫生研究所国家卫生健康委员会精神卫生学重点实验室(北京大学)国家精神心理疾病临床医学研究中心(北京大学第六医院)北京100083 厦门市仙岳医院福建厦门361001 自贡市精神卫生中心四川自贡643020 绵阳市第三人民医院四川绵阳621000 江油市第三人民医院四川江油621700 太原市精神病医院太原030000 北京市房山区精神卫生保健院北京102405 大连市第七人民医院辽宁大连116023

目的:父母患有严重精神障碍,亲子养育功能不良,可能对其未成年子女的身心健康和成长环境造成影响,本研究拟了解患者家庭的亲子沟通状况并探讨其影响因素。方法:采用横断面研究设计,调查患者的12~17岁子女,收集人口学信息、家庭特征和亲... 详细信息

目的:父母患有严重精神障碍,亲子养育功能不良,可能对其未成年子女的身心健康和成长环境造成影响,本研究拟了解患者家庭的亲子沟通状况并探讨其影响因素。方法:采用横断面研究设计,调查患者的12~17岁子女,收集人口学信息、家庭特征和亲子沟通情况;采用亲子沟通量表评估父子/母子沟通的开放性和问题性。结果:149例子女中,70.5%父母诊断为精神分裂症,63.8%家庭不经常沟通;因素分析显示,主要照料者是否为父母影响亲子沟通量表得分(P<0.01);父母照料组较之非父母照料组,母子/父子沟通的总分和开放性得分以及亲子沟通频率均更高(P<0.01)。结论:严重精神障碍患者家庭亲子沟通频率低;在父母不作为子女主要照料者的家庭,亲子沟通情况相对更差。

关键词：亲子沟通精神障碍精神分裂症未成年子女