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Mechanical and damping performances of TPMS lattice metamaterials fabricated by laser powder bed fusion

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China Foundry 2024年第4期21卷 327-333页

作者： Yan-peng wei Huai-qian Li Jing-jing Han Ying-chun Ma Hao-ran Zhou Jing-chang Cheng Jian shi Zhi-quan Miao Bo Yu feng Lin National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space Physics Beijing 100076China

Lattice metamaterials based on three-period minimum surface(TPMS)are an effective means to achieve lightweight and high-strength materials which are widely used in various fields such as aerospace and ***,its vibration and noise reduction,and damping properties have not been fully ***,in this study,the TPMS structures with parameterization were designed by the method of surface migration,and the TPMS structures with high forming quality was manufactured by laser powder bed fusion(LPBF).The mechanical properties and energy absorption characteristics of the beam and TPMS structures were studied and compared by quasi-static *** modal shapes of the beam lattice structures and TPMS structures were obtained by the free modal analysis,and the damping properties of two structures were obtained by modal *** the two structures after heat treatment with the same porosity of 70%,the yield strength of the beam lattice structure reaches 40.76 MPa,elastic modulus is 20.38 GPa,the energy absorption value is 32.23 MJ·m^(-3),the damping ratio is 0.52%.The yield strength,elastic modulus,energy absorption value,and damping ratio of the TPMS structure are 50.74 MPa,25.37 GPa,47.34 MJ·m^(-3),and 0.99%,*** results show that TPMS structures exhibit more excellent mechanical properties and energy absorption,better damping performance,and obvious advantages in structural load and vibration and noise reduction compared with the beam lattice structures under the same porosity.

关键词： lattice metamaterials TPMS energy absorption damping laser powder bed fusion

Entropy variances of pure coherent states in the diffusion channel

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Chinese Physics B 2024年第9期33卷 384-388页

作者： wei-feng Wu Yong Fang Peng Fu School of Mechanical and Electrical Engineering Chizhou UniversityChizhou 247000China Anhui Research Center of Semiconductor Industry Generic Technology Chizhou 247000China

Using the operator correspondence of the real and fictious modes in the thermo entangled state representation, wesolve the quantum master equation describing the diffusion channel and obtain the Kraus operator-sum representation ofits analytical solution. we find that the pure coherent states evolve into the new mixed thermal superposed states in thediffusion channel. Also, we investigate the statistical properties of the initial coherent states and their entropy evolutions inthe diffusion channel, and find that the entropy evolutions are only related to the decay time and without the amplitudes ofthe initial coherent states.

关键词： entangled state representation diffusion channel coherent state entropy evolution

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船舶大功率发电机混沌神经网络建模

中国电机工程学报 2005年第21期25卷 156-162页

作者：施伟锋聂益文上海海事大学电气自动化系上海市浦东新区200135

在分析和研究了Aihara神经元混沌特性的基础上,建立了基于Aihara混沌神经元的Elman局部递归混沌神经网络(CNN),神经元引入混沌特性后增强了神经网络对非线性映射的全局逼近能力。在船舶大功率同步发电机建模中,以船用柴油机输出转矩功... 详细信息

在分析和研究了Aihara神经元混沌特性的基础上,建立了基于Aihara混沌神经元的Elman局部递归混沌神经网络(CNN),神经元引入混沌特性后增强了神经网络对非线性映射的全局逼近能力。在船舶大功率同步发电机建模中,以船用柴油机输出转矩功率和发电机输入励磁电流作为CNN建模与辨识的输入参数;以发电机的输出频率、发电机端电压和输出电流作为CNN建模与辨识的输出参数;采用有导师学习方式,运用基于BP的动态训练方法,最终完成了船舶大功率发电机的动态建模。与其它的ANN建模相比较,用CNN建立的模型的隐层神经元数量少,系统的泛化能力强。

关键词：船舶大功率发电机混沌神经网络建模非线性泛化能力

Low-carbon design towards sustainable city development:Integrating glass space with natural greenery

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Science China(Technological Sciences) 2024年第9期67卷 2659-2674页

作者： CAO shi-Jie ZHANG CunKuan WANG JunQi feng ZhuangBo CHEN Gang HAGHIGHAT Fariborz School of Architecture Southeast UniversityNanjing 210096China Jiangsu Province Engineering Research Center of Urban Heat and Pollution Control Southeast UniversityNanjing 210096China Global Centre for Clean Air Research Department of Civil and Environmental EngineeringFaculty of Engineering and Physical SciencesUniversity of SurreyGuildfordGU27XHUnited Kingdom The Third Construction Co. Ltd.of China Construction Eighth Engineering DivisionNanjing 210046China Energy and Environment Group Department of BuildingCivil and Environmental EngineeringConcordia UniversityMontrealH3G 1M8Canada

The rapid urban development has caused serious problems such as high energy consumption and carbon emissions,especially under the context of climate *** are particularly energy-intensive,generating about one third of global energyrelated carbon *** with active solutions(like mechanical systems),passive solutions offer the potential to balance energy consumption,thermal comfort,and ecological *** potential solution is the integration of green glass space(GGS)into passive building *** is a transitional building space with glass curtain walls that exhibit excellent insulation performance during ***,GGS is susceptible to overheating during summer,which limits its ***,this work proposes a strategy of integrating vertical greenery into GGS,leveraging the nature-based solution of greenery(i.e.,flourishes in summer and withers in winter)to address this seasonal challenge of *** results demonstrated that the strategic application of vertical greenery can effectively mitigate the overheating in GGS and improve comprehensive *** using full coverage of vertical greenery in a linear layout,the air temperature of GGS and cooling energy consumption were largely reduced by 8.02℃and 12.2%,respectively,while the carbon abatement was enhanced by up to 101.11 *** on a comprehensive evaluation of energy,economy,and environmental benefits,it is recommended to use a greenery configuration with 50%coverage in a vertical linear layout for *** integration of greenery into building design can mitigate adverse environmental impacts,reduce energy consumption,and contribute to the sustainable development of low-carbon cities.

关键词： low-carbon design green glass space vertical greenery greenery configuration carbon abatement

基于模型预测的船舶推进电机缺相故障容错控制研究

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推进技术 2022年第11期43卷 447-456页

作者：谢嘉令施伟锋施裕奇上海海事大学电气自动化系上海201306

针对船舶电力推进系统中推进电机缺相故障,提出一种基于模型预测的容错控制方法。根据单相开路后推进电机故障状态方程,重新构建新解耦矩阵得到新坐标系下解耦电流,以此提高预测控制性能。仿真结果表明,模型预测容错电流控制方法在缺相... 详细信息

针对船舶电力推进系统中推进电机缺相故障,提出一种基于模型预测的容错控制方法。根据单相开路后推进电机故障状态方程,重新构建新解耦矩阵得到新坐标系下解耦电流,以此提高预测控制性能。仿真结果表明,模型预测容错电流控制方法在缺相故障下,可降低0.15%转矩稳态误差,削减0.24%转矩脉动,且定子电流具有更好的正弦性,在螺旋桨负载下,船舶电力推进系统转速输出更稳定,具有更强的容错能力,可以实现断相后的稳定运行,提升船舶航行安全可靠性。

关键词：船舶电力推进系统模型预测电流控制缺相故障容错控制解耦矩阵重构

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药物创新制剂产业化及其综合优化技术

中国药学杂志 2019年第21期54卷 1734-1738页

作者：魏世峰李维庸北京罗诺强施医药技术研发中心有限公司北京101111 美国NIRACLE公司宾夕法尼亚州18940

为了让新药尽快获得批准和进入市场,创新制药公司通常会在开发新药的第一代产品时采用成熟且相对简单的剂形。这为以后这些药品创新制剂的开发预留了机会,因为更合理的剂型能改善其临床性能和安全性,同时为患者用药提供便利。创新剂型... 详细信息

为了让新药尽快获得批准和进入市场,创新制药公司通常会在开发新药的第一代产品时采用成熟且相对简单的剂形。这为以后这些药品创新制剂的开发预留了机会,因为更合理的剂型能改善其临床性能和安全性,同时为患者用药提供便利。创新剂型的开发不仅适用于专利到期的新药,也可能适用于较老的药物。但是在开发这些高技术含量的新药时,处方与工艺的开发会面临很多挑战。在本文中,作者根据自己的经验,就启动创新制剂开发项目要考虑的因素和大概流程进行了讨论,并基于质量源于设计的理念和科学文献,对在配方和工艺开发中使用实验设计,统计学和化学计量数据分析以及多元建模的趋势作了回顾。通过对文献中处方与工艺开发实例的分析,作者讨论了合理的实验设计和数据分析方法在创新制剂开发中的重要性。

关键词：创新制剂质量源于设计处方工艺过程

Suppression of low-frequency ultrasound broadband vibration using star-shaped single-phase metamaterials

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Defence Technology（防务技术） 2024年第4期34卷 217-224页

作者： Rui Zhao Jian Zheng Jin Guo Yunbo shi Hengzhen feng Jun Tang Jun Liu Science and Technology on Electronic Test&Measurement Laboratory North University of ChinaTaiyuan 030051ShanxiChina School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation properties,which is configured by hybrid arc and sharp-angle convergent star-shaped *** effect of the dispersion relation and the bandgap characteristic for the scatterers in star-shaped are simulated and *** target bandgap width is extended by optimizing the geometry parameters of arc and sharp-angle convergent *** proposed metamaterial configured by optimized hybrid lattices exhibits remarkable broad bandgap characteristics by bandgap complementarity,and the simulation results verify a 99%vibration attenuation amplitude can be obtained in the frequency of20 k Hz—100 k *** the fabrication of the proposed hybrid configurational star-shaped metamaterial by 3D printing technique,the transmission loss experiments are performed,and the experimental results indicate that the fabricated metamaterial has the characteristics of broadband vibration attenuation and an amplitude greater than 85%attenuation for the target *** results demonstrate that the hybrid configurational star-shaped metamaterials can effectively widen the bandgap and realize high efficiency attenuation,which has capability for the vibration attenuation in the application of highprecise equipment.

关键词： Star-shaped metamaterials Broadband Vibration attenuation Low-frequency ultrasound vibration Transmission loss

Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression

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China Ocean Engineering 2024年第2期38卷 313-325页

作者： DONG Wen-bo ZHOU Li DING shi-feng WANG Ai-ming CAI Jin-yan School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of *** the Arctic,merchant ships with low ice class often navigate in channels opened up by *** in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large *** ship may get stuck if steered into ice fields off the *** this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable *** this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point *** first stage employs the image segmentation method to extract channel *** the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression *** training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel *** evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second.

关键词： ice channel ship navigation identification image segmentation corner point regression

Selective leaching of calcium from mechanically activated mixed rare earth concentrate

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Journal of Rare Earths 2024年第6期42卷 1149-1156,I0006页

作者： Jiang Liu Bingxue Chen Yuanqi feng Yijun Cao Yukun Huang Yuan shi Meng Li Zhongyuan Critical Metals Laboratory School of Chemical EngineeringZhengzhou UniversityZhengzhou450001China State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou730050China

The loss of rare earths(REs)takes place during the pre-decalcification process of mixed rare earth *** an effort to reduce such RE loss,a novel idea to improve the leaching selectivity of Ca to REs by applying selective mechanical activation was ***,regarding the key minerals affecting the leaching selectivity of Ca to REs,the differences in the mechanical activation behaviors of CaF_(2) and REFCO_(3) were studied,and we find that the lattice strain of CaF_(2) increases from 0.21%to 0.42%,whereas that of REFCO_(3) increases from 0.31%to 0.40%.Notably,CaF_(2) demonstrates a larger lattice strain than REFCO_(3),indicating greater mechanical activation energy storage and higher leaching ***,the HCl leaching process was studied.A significant leaching selectivity of Ca to REs,from 21.6 to 35.1,is achieved through mechanical *** Ca leaching rate reaches 80.7%when the RE loss is 2.3%in the activated *** study provides an novel approach for achieving selective extraction of specific components via mechanical activation pretreatment.

关键词： Mixed rare earth concentrate Pre-decalcification Selective mechanical activation Selective leaching