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基于Saber的运算放大器模型及参数测试方法分析

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航天控制 2015年第4期33卷 77-83页

作者：吴海超时晓东陈皓许皓张亮中国航天标准化研究所北京100071

运算放大器是测量和测试电路中最为常见的元器件之一,在电路级仿真中常对元器件库中或者自己建立的运算放大器模型进行性能参数测试和验证。本文介绍了放大器的基本作用及主要性能指标,阐述了Saber仿真软件元器件库中的4类运算放大器的... 详细信息

运算放大器是测量和测试电路中最为常见的元器件之一,在电路级仿真中常对元器件库中或者自己建立的运算放大器模型进行性能参数测试和验证。本文介绍了放大器的基本作用及主要性能指标,阐述了Saber仿真软件元器件库中的4类运算放大器的关键参数含义及使用方法,并使用Saber软件搭建最简测试电路,通过仿真测试运算放大器的输入失调电压、失调电流、共模抑制比和增益带宽积等关键性能参数。仿真结果表明测试电路及测试方法能简单高效并准确地测量出运算放大器模型的性能参数。

关键词： Saber 运算放大器模型参数测试

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浅谈悬挂式玉米联合收获机应用技术

农业技术与装备 2010年第4期 42-43页

作者：孙忠海吴海潮黑龙江省五常市营城子满族乡农业畜牧业综合服务中心 150200 黑龙江省五常市背荫河镇农业畜牧业综合服务中心 150200

根据玉米机收的生产实践,提出选择悬挂式玉米收获机,应考虑适应性、投资效益、动力配套性、产品质量与售后服务、秸秆处理功能等方面的因素,介绍了收获机的特点及使用方法,提出有效的推广措施。

关键词：悬挂式玉米收获机技术应用

Parametric Analysis and Designing Maps for Powder Spreading in Metal Additive Manufacturing

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Computer Modeling in Engineering & Sciences 2025年第2期142卷 2067-2090页

作者： Yuxuan wu Sirish Namilae Department of Aerospace Engineering Embry-Riddle Aeronautical UniversityDaytona BeachFL 32114USA

Powder bed fusion(PBF)in metallic additive manufacturing offers the ability to produce intricate geometries,high-strength components,and reliable ***,powder processing before energy-based binding significantly impacts the final product’s *** maps guide efficient process design to minimize defects,but creating them through experimentation alone is challenging due to the wide range of parameters,necessitating a comprehensive computational parametric *** this study,we used the discrete element method to parametrically analyze the powder processing design space in PBF of stainless steel 316L *** lattice parameter sweeps are often used for parametric analysis,but are computationally *** find that non-uniform parameter sweep based on the low discrepancy sequence(LDS)algorithm is ten times more efficient at exploring the design space while accurately capturing the relationship between powder flow dynamics and bed packing *** introduce a multi-layer perceptron(MLP)model to interpolate parametric causalities within the LDS parameter *** over 99%accuracy,it effectively captures these causalities while requiring fewer ***,we generate processing design maps for machine setups and powder selections for efficient process *** find that recoating speed has the highest impact on powder processing quality,followed by recoating layer thickness,particle size,and inter-particle friction.

关键词： Powder bed fusion additive manufacturing discrete element method parameter sweep process design

The Impact of Different Effective Models for Star Formation on the Properties of Simulated Milky Way-sized Galaxies

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Research in Astronomy and Astrophysics 2025年第1期25卷 194-210页

作者： Yiheng wu Volker Springel Shanghai Astronomical Observatory Chinese Academy of Sciences University of Chinese Academy of Sciences Max-Planck-Institut für Astrophysik

Hydrodynamical cosmological simulations of galaxy formation such as Illustris TNG or Auriga have shown considerable success in approximately matching many galaxy properties,but their treatment of the star-forming interstellar medium (ISM) has relied on heuristic sub-grid ***,recent high-resolution simulations of the ISM that directly resolve the regulation of star formation suggest different mean relations for the dependences of pressure and star formation rate on the average gas *** this study,we adopt such a modern,physically grounded parameterization inspired by the TIGRESS small-scale *** dub this model TEQS and use it for a detailed comparative analysis of the formation and evolution of a Milky Way-sized galaxy when compared with the widely used TNG *** employing high-resolution simulations in tall box setups,we first investigate the structural differences expected for these two models when applied to different self-gravitating gas surface *** results indicate that TEQS produces considerably thinner gaseous layers and can be expected to form stellar distributions with smaller scale-height than TNG,especially at higher surface *** test whether this induces systematic structural differences in cosmological galaxy formation simulations,we carry out zoom-in simulations of 12 galaxies taken from the set of Milky Way-sized galaxies that have been studied in the Auriga *** results for these galaxies shows that disk galaxies formed with the TEQS model have on average very similar stellar mass but are more concentrated in their central regions and exhibit smaller stellar radii compared to those formed with the TNG *** differences in the scale-heights of the formed stellar disks are only marginal,however,suggesting that other factors for setting the thickness of the disk are more important than the applied ISM equation-of-state ***,the predicted galaxy structure is quite similar for TNG and

关键词： Galaxy: evolution Galaxy: formation methods: numerical

Obesogenic effects of six classes of emerging contaminants

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Journal of Environmental Sciences 2025年第5期151卷 252-272页

作者： Siying wu Chaoyu Tong Jing Liu MOE Key Laboratory of Environmental Remediation and Ecosystem Health College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China

There is growing concern about the concept that exposure to environmental chemicals may be contributing to the obesity ***,there is no consensus on the obesogenic effects of emerging contaminants from a toxicological and environmental *** potential human exposure and experimental evidence for obesogenic effects of emerging contaminants need to be systematically *** main objective of this review is to provide recommendations for further subsequent policy development following a critical analysis of the literature for humans and experimental animals exposed to emerging *** article reviews human exposure to emerging contaminants(with a focus on antimicrobials,preservatives,water and oil repellents,flame retardants,antibiotics and bisphenols)and the impact of emerging contaminants on *** emerging contaminants have been widely detected in human biological *** studies provide evidence linking exposure to emerging contaminants to the risks of obesity in *** based on animalmodels and adipose cells show the obesogenic effects of emerging contaminants and identify modes of action by which contaminants may induce changes in body fat accumulation and lipid metabolic *** knowledge gaps in this area and future directions for further investigation are discussed.

关键词： Emerging contaminants Obesity Human exposure Preservatives Flame retardants Plasticizers Antibiotics

Tectonic modes of mantle convection and their implications for Earth's tectonic evolution based on three-dimensional numerical simulations

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Science China Earth Sciences 2025年第1期68卷 270-296页

作者： Song XIANG Jinshui HUANG Bingcheng wu School of Earth and Space Sciences University of Science and Technology of ChinaHefei230026China CAS Center of Excellence in Comparative Planetary Studies Hefei230026China

Five tectonic modes of mantle convection are obtained and analyzed with three-dimensional numerical models in a spherical shell *** five tectonic convective modes are non-plate mobile-lid,plate-like mobile-lid,episodic plate-like mobile-lid,episodic stagnant-lid,and stagnant-lid convective modes,*** typical characteristics of these five tectonic modes and their numerical classification criteria based on plateness,mobility,and their standard deviations are presented and *** results show that the yield stress of the lithosphere has profound effects on the tectonic convective *** the gradual increase of yield stress,the tectonic mode of mantle convection changes from one to another sequentially through the aforementioned five ***,as the Rayleigh number increases,the range of yield stress for the platelike mobile-lid convective mode decreases,and the dimensionless transition stress between different tectonic modes ***,the dimensional transition stress between the non-plate mobile-lid convective mode and plate-like mobile-lid convective mode increases with the increase of Rayleigh number,but decreases between other tectonic ***,we find that the transition stress between different tectonic modes is inversely proportional to the internal heating rate,with the transition stress decreasing as the internal heating rate *** fitting analysis of the transition stress between tectonic modes shows that Earth's current plate tectonics correspond to a lithospheric yield stress of 150–250 MPa,which aligns with the strength of serpentinized mantle rock determined by experimental *** the Archean mantle was 300℃warmer than it is today,then the Earth was in an episodic stagnant-lid convective *** tectonic evolution of the Earth's surface is closely related to the lithospheric strength and the process of thermal *** the lithospheric strength was only 150 MPa,plate tecton

关键词： Tectonic mode of mantle convection Plate-like mobile-lid convection Episodic plate-like mobile-lid convection Episodic stagnant-lid convection Plate tectonics and tectonic evolution of the Earth

Oxidative degradation and upcycling of polyethylene wastes

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Science China Chemistry 2025年第2期68卷 430-443页

作者： Yizhen Che Yanfen wu Zhiqiang Niu State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Ordos Laboratory Ordos 017010China

Plastics have become omnipresent in modern life due to their versatility and ***,this convenience comes at the cost of substantial waste *** inherent chemical stability of plastics complicates its recycling,leading to environmental pollution and ecological *** mini-review highlights recent advancements in addressing this challenge by oxidative transformation of polyethylene(PE)into new functional polymers,value-added chemicals,and carbon-based *** first discuss the introduction of hydroxyl,carbonyl groups onto PE with a focus on the functionalization degree and ***,approaches for PE oxidation into dicarboxylic acids and short-chain oxidized PE are described and compared,with an emphasis on the tandem reactions for converting mixed dicarboxylic acids into other value-added *** also briefly discuss the oxidative transformation of PE into carbon-based materials and summarize the progress in qualitative and quantitative analysis of oxidation ***,we conclude this mini-review by highlighting the challenges and opportunities in the field.

关键词： oxidation polyethylene upcycling chemical conversion plastics

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多通道GPS模拟信号源

数据采集与处理 2012年第6期27卷 677-683页

作者：林静然高鹏周渭民莫明威谢林伶吴海超电子科技大学通信与信息工程学院成都611731

研发了GPS模拟信号源。该信号源能够模拟真实环境中GPS卫星在空中的运转情况,并据此提供相应的GPS卫星信号;同时,该信号源与现有设备中的GPS模块的接口兼容,其输出可直接作为现有GPS模块的输入,在GPS模块中产生相应的时间和方位信息。

关键词：全球定位系统模拟信号源现场可编程门阵列

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CRH3动车虚拟驾驶仿真系统的设计与实现

华东交通大学学报 2012年第2期29卷 31-35,46页

作者：吴海超张安全南京铁道职业技术学院江苏南京210031 郑州捷安高科股份有限公司河南郑州450001

CRH3动车采用众多高新技术,给动车驾驶带来了极大挑战。CRH3动车虚拟驾驶仿真系统的开发,旨在对动车司机进行模拟驾驶、故障处理、非正常行车处理等方面的多媒体教学培训,培养动车司机的操作应变能力。CRH3动车虚拟驾驶仿真系统采用虚... 详细信息

CRH3动车采用众多高新技术,给动车驾驶带来了极大挑战。CRH3动车虚拟驾驶仿真系统的开发,旨在对动车司机进行模拟驾驶、故障处理、非正常行车处理等方面的多媒体教学培训,培养动车司机的操作应变能力。CRH3动车虚拟驾驶仿真系统采用虚拟现实技术,对CRH3动车组驾驶进行全三维虚拟化列车逻辑模型仿真,可以展示不可视、不可摸、不可入列车部位的结构、布局及连接方式,轻松设置现实中不经常遇到而采用实物方式设置又很麻烦的故障,能反复无破坏地设置、查找和排除电气设备等系统故障,提高了培训效率、降低了培训成本,解决了铁路部门在高速铁路现场难以进行司机培训的问题培训,效果良好。

关键词： CRH3虚拟仿真模拟驾驶故障处理非正常行车