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PHYSICAL SIMULATION BASED INTELLIGENT SYSTEM FOR THE PREDICTION OF SHEET METAL DRAWING CAPABILITY

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Acta Metallurgica Sinica(English Letters) 2000年第2期13卷 451-458页

作者： D.Lv D.N.He x.J.bao Y.q.Zhang x.Y.Ruan J.L.Cheng J.Y.Jiang National Die&Mold CAD Engineering Research Center Shanghai Jiaotong UniversityShanghai 200030China Shanghai Volkswagen Automotive Company Limited Shanghai 201805China

With the combination of a new theoretical formula, physical simulation ex.eriments, the technology of artificial neural network and database, an intelligent system for the prediction of sheet metal drawing capability is constructed for the first time. A modified criterion for sheet metal drawing capability is proposed in this paper, namely, the Technological Limiting Drawing Ratio, TLDR = f(R, n, s, t, F, μ,r_d,r_p…). Based on the studies of other scholars, a new formula is derived to predict the TLDR in this paper. Then a series of orthogonal physical simulation ex.eriments are designed to investigate the effect of technological parameters on the TLDR, and the results are analyzed in the paper. Then the predicting system is constructed with the combination of the theoretical formula, orthogonal ex.eriments, the technology of artifocial neural network and database. The predicted results show good agreements with ex.erimental data, so it can be used to avoid the blindness in the selection of sheet metal before stamping. The system operates under the Windows operating system, and it supports the mechanism of Client/Server as well as Intranet, so the system has high engineering value.

关键词： TLDR theoretical analysis physical simulation orthogonal ex.eriments neural network database predicting system

Post-CMOS processing challenges and design developments of CMOS-MEMS microheaters for local CNT synthesis

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Microsystems & Nanoengineering 2023年第6期9卷 281-295页

作者： Avisek Roy bao q.Ta Mehdi Azadmehr Knut E.Aasmundtveit Department of Microsystems University of South-Eastern Norway3184 HortenNorway

Carbon nanotubes(CNTs)can be locally grown on custom-designed CMOS microheaters by a thermal chemical vapour deposition(CVD)process to utilize the sensing capabilities of CNTs in emerging micro-and nanotechnology *** such a direct CMOS-CNT integration,a key req.irement is the development of necessary post-processing steps on CMOS chips for fabricating CMOS-MEMS polysilicon heaters that can locally generate the req.ired CNT synthesis temperatures(~650-900℃).In our post-CMOS processing,a subtractive fabrication techniq.e is used for micromachining the polysilicon heaters,where the passivation layers in CMOS are used as masks to protect the *** dielectric etching,it is necessary to achieve high selectivity,uniform etching and a good etch rate to fully ex.ose the polysilicon layers without causing *** achieved successful post-CMOS processing by developing two-step reactive ion etching(RIE)of the SiO2 dielectric layer and making design improvements to a second-generation CMOS *** the dry etching process,CMOS-MEMS microheaters are partially suspended by SiO2 wet etching with minimum damage to the ex.osed aluminium layers,to obtain high thermal *** fabricated microheaters are then successfully utilized for synthesizing CNTs by a local thermal CVD *** CMOS post-processing challenges and design aspects to fabricate CMOS-MEMS polysilicon microheaters for such high-temperature applications are detailed in this *** developed process for heterogeneous monolithic integration of CMOS-CNT shows promise for wafer-level manufacturing of CNT-based sensors by incorporating additional steps in an already ex.sting foundry CMOS process.

关键词： synthesis steps damage

Application of lung microphysiological systems to COVID-19 modeling and drug discovery:a review

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Bio-Design and Manufacturing 2021年第4期4卷 757-775页

作者： Argus M.Sun Tyler Hoffman bao q.Luu Nureddin Ashammakhi Song Li Department of Bioengineering Samueli School of EngineeringUniversity of California-Los Angeles420 Westwood Plaza 5121 Engineering V University of CaliforniaLos AngelesCA 90095-1600USA UC San Diego Healthcare UCSDLa JollaCA 92037USA Pulmonary Diseases and Critical Care Scripps Green HospitalScripps HealthLa JollaCA 92037USA Department of Biomedical Engineering College of EngineeringMichigan State UniversityEast LansingMI 48824USA Department of Medicine David Geffen School of MedicineUCLALos AngelesCA 90095USA

There is a pressing need for effective therapeutics for coronavirus disease 2019(COVID-19),the respiratory disease caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)*** process of drug development is a costly and meticulously paced process,where progress is often hindered by the failure of initially promising *** aid this chal-lenge,in vitro human microphysiological systems need to be refined and adapted for mechanistic studies and drug screening,thereby saving valuable time and resources during a pandemic *** SARS-CoV-2 virus attacks the lung,an organ where the uniq.e three-dimensional(3D)structure of its functional units is critical for proper respiratory *** in vitro lung models essentially recapitulate the distinct tissue structure and the dynamic mechanical and biological interactions between different cell *** model systems include Transwell,organoid and organ-on-a-chip or microphysiological systems(MPSs).We review models that have direct relevance toward modeling the pathology of COVID-19,including the processes of inflammation,edema,coagulation,as well as lung immune *** also consider the practical issues that may influence the design and fabrication of *** role of lung MPS is addressed in the contex. of multi-organ models,and it is discussed how high-throughput screening and artificial intelligence can be integrated with lung MPS to accelerate drug development for COVID-19 and other infectious diseases.

关键词： Bioengineering Microfluidics COVID-19 Organ-on-a-chip Lung Microvascular networks Drug development

Ex.ension/Compression-Controlled Complete Band Gaps in 2D Chiral Sq.are-Lattice-Like Structures

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Acta Mechanica Solida Sinica 2018年第1期31卷 51-65页

作者： Y. L. Huang N. Gao W.q. Chen R.H. bao Department of Engineering Mechanics Zhejiang University Hangzhou 310027 China State Key Lab of CAD & CG Zhejiang University Hangzhou 310058 China Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Zhejiang University Hangzhou 310027 China Soft Matter Research Center Zhejiang University Hangzhou 310027 China

Achieving tunable band gaps in a structure by ex.ernal stimuli is of great importance in acoustic applications. This paper aims to investigate the tunability of band gaps in sq.are-lattice-like elastic periodic structures that are usually not featured with notable band gaps. Endowed with chirality, the periodic structures here are able to undergo imperfection-insensitive large deformation under ex.ension or compression. The influences of geometric parameters on band gaps are discussed via the nonlinear finite element method. It is shown that the band gaps in such structures with curved beams can be very rich and, more importantly, can be efficiently and robustly tuned by applying appropriate mechanical loadings without inducing buckling. As ex.ected, geometry plays a more significant role than material nonlinearity does in the evolution of band gaps. The dynamic tunability of band gaps through mechanical loading is further studied. Results show that closing, opening, and shifting of band gaps can be realized by ex.rting real-time global ex.ension or compression on the structure. The proposed periodic structure with well-designed chiral symmetry can be useful in the design of particular acoustic devices.

关键词： Band gap Tunability Sq.are-lattice-like periodic structure Chiral symmetry,Large deformation

Preparation and characterization of Ce_(0.8)Sm_(0.2)O_(1.9)-La_(0.8)Sr_(0.2)Cr_(0.5)Fe_(0.5)O_(3-δ) dual-phase membranes for ox.gen permeation

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Journal of Materiomics 2020年第1期6卷 224-231页

作者： Guangjun Zhang x.aonan bao Fanrong Zeng Nguyen q.Minh Shaorong Wang School of Chemical Engineering and Technology China University of Mining and Technology1st Da-xue RoadXuzhouJiangsu221116China Jiangsu Province Engineering Laboratory of High Efficient Energy Storage Technology and Eq.ipments 1st Da-xue RoadXuzhouJiangsu221116China University of California San Diego9500 Gilman Drive La JollaCA92093-0147USA

In this study,with La_(0.8)Sr_(0.2)Cr_(0.5)Fe_(0.5)O_(3-δ)(LSCrF)and Ce_(0.8)Sm_(0.2)O_(1.9)(SDC)taken as the electronic conducting phase and the ox.de ion conductor,respectively,dual-phase composite ceramic membranes with or without 3%(in mole)Y_(2)O_(3) stable ZrO_(2)(3YSZ)support were prepared and tested as ox.gen separation ***,the ox.gen transmission performance was tested by the electrochemical method based on the limiting *** results obtained with this method coincide with those acq.ired by means of gas ***,the dependences of ox.gen permeation rate on ox.gen partial pressure,temperature and ceramic membrane thickness were *** air was used as the sweeping gas on the porous 3YSZ supported SDC-LSCrF dual-phase membrane,the ox.gen permeation rate can reach 0.73,0.82,0.90 and 0.97 mL cm^(-2) min^(-1) at 650,700,750 and 800℃,respectively.

关键词： Dual-phase Ceramic membranes Ox.gen permeation Limiting current

Estimation of J—R Curves for Small-Sized COEC Specimens and Its Application Considering Crack-Tip Cons tr aints

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Acta Mechanica Solida Sinica 2019年第3期32卷 261-276页

作者： G.W.He C.bao L.x.Cai Y.J.Wu Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China

The normalization method has been employed to estimate the J-resistance (J—R) curves for C-shaped outside edge-notched compression (COEC) specimens of SA-508 steel. The COEC specimens present the lowest J—R curves in comparison with other three types of specimens. Based on the J—q.M met hod, the constraint parame ter q.determined at the mid-plane in the through-thickness direction of the specimen is used to approx.mately q.antify the threedimensional crack-tip constraint for COEC specimens. Combining with the previous ex.eriments on J—R curves, the constraint-coirected J—R curves for SA-508 steel specimens are given, which may be used to predict the fracture toughness of actual cracked components in structural integrity assessment.

关键词： Ductile fracture toughness COEC specimen Dimensionless load separation principle Normalization method Crack-tip constraint J-q.M method

Corrosion and cavitation erosion resistance enhancement of cast Ni–Al bronze by laser surface melting

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Journal of Iron and Steel Research International 2022年第2期29卷 359-369页

作者： q.N.Song Y.Tong H.L.Li H.N.Zhang N.x. G.Y.Zhang Y.F.bao W.Liu Z.G.Liu Y.x.q.ao Engineering Research Center of Dredging Technology of Ministry of Education Hohai UniversityChangzhou213022JiangsuChina College of Mechanical and Electrical Engineering Hohai UniversityChangzhou213022JiangsuChina College of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212003JiangsuChina

Laser surface melting (LSM) was applied on a cast Ni–Al bronze (NAB), which was a crucial material for marine ship propellers. A 720 μm-thick LSM layer with fine eq.iax.d and dendritic microstructures was obtained. After immersion for 30 days, the corrosion rate of cast NAB was reduced by 25% after LSM. Preferential corrosion occurred and deep corrosion pits appeared at α + κIII microstructure for the cast NAB. LSM NAB underwent general corrosion, and a much more protective film formed on the surface because of the homogenized microstructure. The mass loss of the cast NAB was approx.mately 2.1 times larger than that of LSM NAB after cavitation erosion (CE) in 3.5 wt.% NaCl solution for 5 h. For the two materials, the mechanical impact effect was dominantly responsible for CE damage. Therefore, the improved hardness and homogenized microstructure contributed to the improved CE resistance of LSM NAB. CE destructed the film, shifted the open circuit potential toward a more negative value, and raised the current density by an order of magnitude. Corrosion at the cast eutectoid microstructure and the dendrites of LSM NAB facilitates the degradation under the cavitation attack. CE-corrosion synergy was largely caused by corrosion-enhanced-CE.

关键词： Laser surface melting Ni-Al bronze Microstructure Corrosion Cavitation erosion Synergy

Ocean satellite data assimilation ex.eriments in FIO-ESM using ensemble adjustment Kalman filter

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Science China Earth Sciences 2016年第12期59卷 484-494页

作者： CHEN Hui YIN x.n q.ang bao Ying q.AO Fang Li The First Institute of Oceanography State Oceanic Administration Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration

Using Ensemble Adjustment Kalman Filter(EAKF), two types of ocean satellite datasets were assimilated into the First Institute of Oceanography Earth System Model(FIO-ESM), v1.0. One control ex.eriment without data assimilation and four assimilation ex.eriments were conducted. All the ex.eriments were ensemble runs for 1-year period and each ensemble started from different initial conditions. One assimilation ex.eriment was designed to assimilate sea level anomaly(SLA); another, to assimilate sea surface temperature(SST); and the other two assimilation ex.eriments were designed to assimilate both SLA and SST but in different orders. To ex.mine the effects of data assimilation, all the results were compared with an objective analysis dataset of EN3. Different from the ocean model without coupling, the momentum and heat flux.s were calculated via air-sea coupling in FIO-ESM, which makes the relations among variables closer to the reality. The outputs after the assimilation of satellite data were improved on the whole, especially at depth shallower than 1000 m. The effects due to the assimilation of different kinds of satellite datasets were somewhat different. The improvement due to SST assimilation was greater near the surface, while the improvement due to SLA assimilation was relatively great in the subsurface. The results after the assimilation of both SLA and SST were much better than those only assimilated one kind of dataset, but the difference due to the assimilation order of the two kinds of datasets was not significant.

关键词： Earth system model Ocean satellite data Ensemble adjustment Kalman filter Data assimilation

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水平层状介质中基于DTA的三维电磁波逆散射快速模拟算法

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地球物理学报 2007年第5期50卷 1595-1605页

作者：魏宝君 LIU q.H 中国石油大学(华东)物理科学与技术学院山东东营257061 Department of Electrical&Computer Engineering Duke University

为提高水平层状介质中三维电磁波散射和逆散射数值模拟的效率,在对角张量近似(DTA)的基础上根据不同回代方式得到了求解积分方程的DTA1和DTA2两种近似.这两种近似可以作为计算积分方程稳定型双共轭梯度快速Fourier变换(BCGS-FFT)算法的... 详细信息

为提高水平层状介质中三维电磁波散射和逆散射数值模拟的效率,在对角张量近似(DTA)的基础上根据不同回代方式得到了求解积分方程的DTA1和DTA2两种近似.这两种近似可以作为计算积分方程稳定型双共轭梯度快速Fourier变换(BCGS-FFT)算法的初始猜测值和预条件因子,从而形成效率更高的混合DTA-BCGS算法.散射实例说明了DTA2的高精度和混合DTA-BCGS算法尤其是混合DTA2-BCGS算法的高效率.由于DTA2近似程度更高,将DTA2与变型Born迭代反演方法(DBIM)相结合形成了一种对三维异常体进行重构的快速电磁波逆散射技术.文中的逆散射实例说明所开发的逆散射技术对重构水平层状介质中的任意三维异常体是非常有效的.

关键词：积分方程对角张量近似(DTA) 稳定型双共轭梯度快速Fourier变换水平层状介质逆散射变型Born迭代方法(DBIM)