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Photonics Research 2024年第7期12卷 1494-1501页

作者： YANBO jin linPENG LU SHUN zhou JIE zhou YAO FAN CHAO ZUO Smart Computational Imaging Laboratory(SCILab) School of Electronic and Optical EngineeringNanjing University of Science and TechnologyNanjing 210094China Smart Computational Imaging Research Institute(SCIRI)of Nanjing University of Science and Technology Nanjing 210019China Jiangsu Key Laboratory of Spectral Imaging&Intelligent Sense Nanjing 210094China

The transport-of-intensity equation(TIE) enables quantitative phase imaging(QPI) under partially coherent illumination by measuring the through-focus intensities combined with a linearized inverse reconstruction algorithm. However, overcoming its sensitivity to imaging settings remains a challenging problem because of the difficulty in tuning the optical parameters of the imaging system accurately and because of the instability to long-time measurements. To address these limitations, we propose and experimentally validate a solution called neural-field-assisted transport-of-intensity phase microscopy(NFTPM) by introducing a tunable defocus parameter into neural field. Without weak object approximation, NFTPM incorporates the physical prior of partially coherent image formation to constrain the neural field and learns the continuous representation of phase object without the need for training. Simulation and experimental results of He La cells demonstrate that NFTPM can achieve accurate, partially coherent QPI under unknown defocus distances, providing new possibilities for extending applications in live cell biology.

关键词： field coherent phase

A reweighted damped singular spectrum analysis method for robust seismic noise suppression

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Petroleum Science 2024年第3期21卷 1671-1682页

作者： Wei-lin Huang Yan-Xin zhou Yang zhou Wei-Jie Liu Ji-Dong Li State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China SINOPEC Petroleum Exploration and Production Research Institute Beijing102206China SINOPEC Geophysical Research Institute Nanjing211103jiangsuChina

(Multichannel)Singular spectrum analysis is considered as one of the most effective methods for seismic incoherent noise *** utilizes the low-rank feature of seismic signal and regards the noise suppression as a low-rank reconstruction ***,in some cases the seismic geophones receive some erratic disturbances and the amplitudes are dramatically larger than other *** presence of this kind of noise,called erratic noise,makes singular spectrum analysis(SSA)reconstruction unstable and has undesirable effects on the final *** robustify the low-rank reconstruction of seismic data by a reweighted damped SSA(RD-SSA)*** incorporates the damped SSA,an improved version of SSA,into a reweighted *** damping operator is used to weaken the artificial disturbance introduced by the low-rank projection of both erratic and random *** central idea of the RD-SSA method is to iteratively approximate the observed data with the quadratic norm for the first iteration and the Tukeys bisquare norm for the rest *** RD-SSA method can suppress seismic incoherent noise and keep the reconstruction process robust to the erratic *** feasibility of RD-SSA is validated via both synthetic and field data examples.

关键词： Singular spectrum analysis Damping operator Seismic erratic noise Seismic signal processing Robust low-rank reconstruction

Positive definiteness of real quadratic forms resulting from the variable-step L1-type approximations of convolution operators

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Science China Mathematics 2024年第2期67卷 237-252页

作者： Hong-lin Liao Tao Tang Tao zhou School of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211106China Division of Science and Technology BNU-HKBU United International CollegeZhuhai 519087China SUSTech International Center for Mathematics Shenzhen 518055China NCMIS&LSEC Institute of Computational Mathematics and Scientific/Engineering ComputingAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China

The positive definiteness of real quadratic forms with convolution structures plays an important rolein stability analysis for time-stepping schemes for nonlocal operators. In this work, we present a novel analysistool to handle discrete convolution kernels resulting from variable-step approximations for convolution *** precisely, for a class of discrete convolution kernels relevant to variable-step L1-type time discretizations, weshow that the associated quadratic form is positive definite under some easy-to-check algebraic conditions. Ourproof is based on an elementary constructing strategy by using the properties of discrete orthogonal convolutionkernels and discrete complementary convolution kernels. To our knowledge, this is the first general result onsimple algebraic conditions for the positive definiteness of variable-step discrete convolution kernels. Using theunified theory, we obtain the stability for some simple nonuniform time-stepping schemes straightforwardly.

关键词： discrete convolution kernels positive definiteness variable time-stepping orthogonal convolution kernels complementary convolution kernels

Establishing the link between D-mannose and juvenile grass carp(Ctenopharyngodon idella):Improved growth and intestinal structure associated with endoplasmic reticulum stress,mitophagy,and apical junctional complexes

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Animal Nutrition 2024年第3期18卷 450-463页

作者： Chong Zhang lin Feng Pei Wu Yang Liu Xiaowan jin Hongmei Ren Hua Li Fali Wu Xiaoqiu zhou Weidan Jiang Animal Nutrition Institute Sichuan Agricultural UniversityChengdu 611130China Fish Nutrition and Safety Production University Key Laboratory of Sichuan ProvinceSichuan Agricultural UniversityChengdu 611130China Key Laboratory of Animal Disease-Resistance Nutrition Ministry of EducationMinistry of Agriculture and Rural AffairsKey Laboratory of Sichuan ProvinceChengdu 611130China

D-mannose,essential for protein glycosylation,has been reported to have immunomodulatory effects and to maintain intestinal flora *** addition to evaluating growth performance,we examined the impact of D-mannose on the structure of epithelial cells and apical junction complexes in the animal *** 1800 grass carp(16.20±0.01 g)were randomly divided into six treatments with six replicates of 50 fish each and fed with six different levels of D-mannose(0.52,1.75,3.02,4.28,5.50 and 6.78 g/kg diet)for 70 *** study revealed that D-mannose increased feed intake(P 0.05).D-mannose supplementation at 1.75 g/kg increased crude protein content in fish and lipid production value(Pling *** alleviation of ER stress may be linked to the phosphomannomutase(PMM)-mediated enhancement of protein *** addition,ubiquitin-dependent[PTEN-induced putative kinase 1(PINK1)/Parkin]and ubiquitin-independent[BCL2-interacting protein 3-like(BNIP3L),BCL2-interacting protein 3(BNIP3),and FUN14 domain containing 1(FUNDC1)]mitophagy may play a role in maintaining cellular redox *** enhancement of intercellular structures includes enhancing tight junction and adherent junction structures,which may be closely associated with the small Rho GTPase pr

关键词： Grass carp(Ctenopharyngodon idella) D-mannose Intestine structure Endoplasmic reticulum stress Mitophagy Apical junctional complex

Dietary curcumin alleviates intestinal damage induced by ochratoxin A in juvenile grass carp(Ctenopharyngodon idella):Necroptosis and inflammatory responses

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Animal Nutrition 2024年第3期18卷 119-132页

作者： Piao Zhao Wei Dan Jiang Pei Wu Yang Liu Hong Mei Ren Xiao Wan jin lin Feng Xiao Qiu zhou Animal Nutrition Institute Sichuan Agricultural UniversityChengdu 611130SichuanChina Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province Sichuan Agricultural UniversityChengdu 611130SichuanChina Key Laboratory of Animal Disease-Resistance Nutrition Ministry of EducationMinistry of Agriculture and Rural AffairsKey Laboratory of Sichuan ProvinceSichuan611130China

Ochratoxin A(OTA)is one of the most common pollutants in aquatic *** a first line of defense,intestinal barriers could be utilized against OTA in order to prevent *** product supplementation is one of the most popular strategies to alleviate toxicity induced by mycotoxins,but there is a lack of knowledge about how it functions in the teleost *** this study,720 juvenile grass carp of about 11 g were selected and four treatment groups(control group,OTA group,curcumin[Cur]group,and OTA+Cur group)were set up to conduct a 60-day growth *** the test,the growth performance and intestinal health related indexes of grass carp were *** addition of dietary Cur could have the following main results:(1)inhibit absorption and promote efflux transporters mRNA expression,reducing the residuals of OTA,(2)decrease oxidative stress by reducing oxidative damage and enhancing the expression of antioxidant enzymes,(3)promote mitochondrial fusion proteins to inhibit the expression of mitotic proteins and mitochondrial autophagy proteins and enhance mitochondrial function,(4)reduce necroptosis-related gene expression through inhibiting the tumor necrotic factor receptor-interacting protein kinase/mixed lineage kinase domain-like pathway,(5)reduce the expression of pro-inflammatory factors by inhibiting the Toll-like receptor 4/nuclear factor-κB signaling pathway to alleviate the intestinal inflammatory *** summary,the results suggested that Cur could alleviate OTA-induced intestinal damage by enhancing antioxidant capacity and mitochondrial function as well as reducing necroptosis and inflammation in the grass carp *** study provided a theoretical basis and production implications for dietary Cur that could improve growth performance and alleviate the intestinal damage induced by OTA in fish.

关键词： Curcumin Ochratoxin A Grass carp growth performance Mid-intestine mitochondria function Necroptosis

Low-temperature chemistry in plasma-driven ammonia oxidative pyrolysis

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Green Energy & Environment 2024年第9期9卷 1477-1488页

作者： Mingming Zhang Qi Chen Guangzhao zhou jintao Sun He lin School of Mechanical Electronic and Control Engineering Beijing Jiaotong University School of Mechanical Engineering Shanghai Jiao Tong University

Ammonia is gaining increasing attention as a green alternative fuel for achieving large-scale carbon emission reduction. Despite its potential technical prospects, the harsh ignition conditions and slow flame propagation speed of ammonia pose significant challenges to its application in engines. Non-equilibrium plasma has been identified as a promising method, but current research on plasma-enhanced ammonia combustion is limited and primarily focuses on ignition characteristics revealed by kinetic models. In this study, low-temperature and low-pressure chemistry in plasma-assisted ammonia oxidative pyrolysis is investigated by integrated studies of steady-state GC measurements and mathematical simulation. The detailed kinetic mechanism of NH3decomposition in plasma-driven Ar/NH3and Ar/NH3/O2mixtures has been developed. The numerical model has good agreements with the experimental measurements in NH3/O2consumption and N2/H2generation, which demonstrates the rationality of modelling. Based on the modelling results, species density profiles, path flux and sensitivity analysis for the key plasmaproduced species such as NH2, NH, H2, OH, H, O, O（1D）, O2（a1△g）, O2（b1∑g+）, Ar*, H-, Ar+, NH3+, O2-in the discharge and afterglow are analyzed in detail to illustrate the effectiveness of the active species on NH3excitation and decomposition at low temperature and relatively higher E/N values. The results revealed that NH2, NH, H as well as H2are primarily generated through the electron collision reactions e + NH3→ e + NH2+ H, e + NH3→ e + NH + H2and the excited-argon collision reaction Ar*+ NH3+ H → Ar + NH2+ 2H, which will then react with highly reactive oxidative species such as O2*, O*, O, OH, and O2to produce stable products of NOx and H2O. NH3→ NH is found a specific pathway for NH3consumption with plasma assistance, which further highlights the enhanced kinetic effects.

关键词： Non-equilibrium plasma Ammonia fuel Oxidative pyrolysis Pathway flux analysis Sensitivity analysis

A CAD-BEM geometry transformation method for face-based primary geometric input based on closed contour recognition

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Building Simulation 2024年第2期17卷 335-354页

作者： Jun Xiao Hao zhou Shiji Yang Deyin Zhang Borong lin Department of Building Science School of ArchitectureTsinghua UniversityBeijing100084China Key Laboratory of Eco Planning&Green Building Ministry of EducationTsinghua UniversityBeijing100084China Institute for Urban Governance and Sustainable Development Tsinghua UniversityBeijing100084China

Performance analysis during the early design stage can significantly reduce building energy ***,it is difficult to transform computer-aided design(CAD)models into building energy models(BEM)to optimize building *** model structures for CAD and BEM are *** this study,geometry transformation methods was implemented in BES tools for the early design stage,including auto space generation(ASG)method based on closed contour recognition(CCR)and space boundary topology calculation *** program is developed based on modeling tools SketchUp to support the CAD format(like*.stl,*.dwg,*.ifc,etc.).It transforms face-based geometric information into a zone-based tree structure model that meets the geometric requirements of a single-zone BES combined with the other thermal parameter inputs of the *** addition,this study provided a space topology calculation method based on a single-zone BEM *** program was developed based on the SketchUp modeling tool to support additional CAD formats(such as*.stl,*.dwg,*.ifc),which can then be imported and transformed into*.*** to current methods mostly focused on BIM-BEM transformation,this method can ensure more modeling *** method was integrated into a performance analysis tool termed MOOSAS and compared with the current version of the transformation *** were tested on a dataset comprising 36 conceptual models without partitions and six real cases with detailed *** ensures a transformation rate of two times in any bad model condition and costs only 1/5 of the time required to calculate each room compared to the previous version.

关键词： geometry transformation building energy model computer aid design closed contour recognition

Thickness regression for backfill grouting of shield tunnels based on GPR data and CatBoost&BO-TPE:A full-scale model test study

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Underground Space 2024年第4期17卷 100-119页

作者： Kang Li Xiongyao Xie Biao zhou Changfu Huang Wei lin Yihan zhou Cheng Wang Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground of Ministry of Education Tongji UniversityShanghai 200092China China Railway 15th Bureau Group Co.Ltd. Shanghai 200070China State Grid Shanghai Municipal Electric Power Company Shanghai 200122China

Ground penetrating radar(GPR)is a vital non-destructive testing(NDT)technology that can be employed for detecting the backfill grouting of shield *** achieve intelligent analysis of GPR data and overcome the subjectivity of traditional data processing methods,the CatBoost&BO-TPE model was constructed for regressing the grouting thickness based on GPR waveforms.A full-scale model test and corresponding numerical simulations were carried out to collect GPR data at 400 and 900 MHz,with known backfill grouting *** model test helps address the limitation of not knowing the grout body condition in actual field *** data were then used to create machine learning *** method of feature selection was proposed based on the analysis of feature importance and the electromagnetic(EM)propagation law in *** research shows that:(1)the CatBoost&BO-TPE model exhibited outstanding performance in both experimental and numerical data,achieving R^(2)values of 0.9760,0.8971,0.8808,and 0.5437 for numerical data and test data at 400 and 900 *** outperformed extreme gradient boosting(XGBoost)and random forest(RF)in terms of performance in the backfill grouting thickness regression;(2)compared with the full-waveform GPR data,the feature selection method proposed in this paper can promote the performance of the *** selected features within the 5–30 ns of the A-scan can yield the best performance for the model;(3)compared to GPR data at 900 MHz,GPR data at 400 MHz exhibited better performance in the CatBoost&BO-TPE *** indicates that the results of the machine learning model can provide feedback for the selection of GPR parameters;(4)the application results of the trained CatBoost&BO-TPE model in engineering are in line with the patterns observed through traditional processing methods,yet they demonstrate a more quantitative and objective nature compared to the traditional method.

关键词： Shield tunnel Backfill grouting GPR Model test gprMax Machine learning CatBoost&BO-TPE Thickness regression

Shock Initiation Experiments with Modeling on a DNAN Based MeltCast Insensitive Explosive

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Defence Technology（防务技术） 2024年第2期32卷 655-662页

作者： Feichao Miao Dandan Li Yangfan Cheng Junjiong Meng lin zhou School of Chemical Engineering Anhui University of Science and TechnologyHuainan 232001China Composite Explosive Research Department Xi'an Modern Chemistry Research InstituteXi'an 710065China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

2,4-dinitroanisole(DNAN)is a good replacement for 2,4,6-trinitrotoluene(TNT)in melt-cast explosives due to its superior *** the increasing use of DNAN-based melt-cast explosives,the prediction of reaction violence and hazard assessment of the explosives subjected to shock is of great *** study investigated the shock initiation characteristics for a DNAN-based melt-cast explosive,DHFA,using the one-dimensional Lagrangian *** embedded manganin gauges in the apparatus record the pressure histories at four Lagrangian positions and show that shock-todetonation transition in DHFA needs a high input shock *** experimental data are analyzed to calibrate the Ignition and Growth *** calibration is performed using an objective function based on both pressure history and the arrival time of *** agreement between experimental and calculated pressure histories indicates the high accuracy of the calibrated parameters with the optimization method.

关键词： 2,4-Dinitroanisole(DNAN) Shock initiation Insensitive explosives Ignition and growth model Equation of state(EOS)

Experimental,Numerical,and Analytical Studies on the Bending of Mechanically lined Pipe

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China Ocean Engineering 2024年第2期38卷 221-232页

作者： WEI Wen-bin YUAN lin zhou Jia-sheng LIU Zheng State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China School of Mechanical Engineering Tianjin UniversityTianjin 300072China

Mechanically lined pipe(MLP)is often used for offshore oil and gas transport because of its low cost and corrosion *** installation and operation,the pipe may undergo severe bending deformation,which causes the liner to separate from the outer pipe and buckles,affecting the stability of the whole *** this paper,the buckling response of MLP subjected to bending is investigated to clarify its bending characteristics by employing both experiments,numerical simulation,as theoretical *** types of MLPs were manufactured with GB 45 carbon steel(SLP)and Al 6061(ALP)used as the outer pipe material,*** hydraulic expansion and bending experiments of small-scale MLPs are *** addition to the ovalized shape of the cross-section for the SLP specimens,the copper liner was found to wrinkle on the compressive *** contrast,the liner of ALP remains intact without developing any wrinkling and collapse *** addition,a dedicated numerical framework and theoretical models were also *** was found both the manufacturing and bending responses of the MLP can be well reproduced,and the predicted maximum moment and critical curvatures are in good agreement with the experimental results.

关键词： lined pipe bending nonlinear ring theory buckling plasticity