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Local scour by multiple slit-type energy dissipaters

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Journal of Hydrodynamics 2020年第6期32卷 1221-1224页

作者： Li yao jian-hua Wu College of Water Conservancy and Ecological Engineering Nanchang Institute of TechnologyNanchang330099China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China

Energy dissipation and scour control are all the key issues for the design of hydraulic *** the basis of the high energy dissipation for the multiple slit-type energy dissipaters(M-STED)developed by the authors,in this work,the characteristics of the scour hole for the M-STED were experimentally investigated through three sets of those physical models with five cases and a scour hole form index was *** results show that,the M-STED results in not only the high energy dissipation but also the mild upstream slope of the scour hole thanks to the scour hole form index of larger than 0.5,which is in favor of the safety of the release works.

关键词： Energy dissipation scour scour hole form index multiple slit-type energy dissipater

Corrosion resistance properties of colored zirconium conversion coating and powder coating on cold-rolled steel

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Rare Metals 2023年第3期42卷 1005-1010页

作者： Ai-hua Wu yao-Zu Wang Tong-Kuan Xu Zhi Li Sheng-ji Luan Feng-Zuo Qu Shenzhen Key Laboratory of Environment Simulation and Pollution Control PKU-HKUST Shenzhen-HongKong InstitutionShenzhen 518057China Faculty of Light Industry and Chemical Engineering Dalian Polytechnic UniversityDalian 116034China

jiuhe Corporation developed a new surface pretreatment for producing a phosphate-free and colored zirconium conversion coating on cold-rolled steel(CRS).Scanning electron microscopy(SEM)and energy-dispersive spectroscopy(EDS)were applied to study the surface morphology and elemental composition of the golden yellow-colored conversion *** trochemic al impedance spectroscopy(EIS)was used to investigate the electrochemical performance of the conversion coatings with different *** corrosion resistance properties of the powder coatings were characterized using the neutral salt spray test(NSS)and the tape adhesion *** EIS and NSS results demonstrate that the colored zirconium conversion coatings exhibit excellent corrosion resistance properties compared with the bare *** golden yellow-colored conversion coating has a maximum EIS value(748Ω·cm^(2))and achieves 0 mm degree of corrosion,as stipulated by EN ISO *** paper proposes a hypothesis concerning the ZrO_(2)-(β-FeOOH)-polymer conversion reaction to explain the color changes.

关键词： Surface pretreatment Colored conversion coating Zirconium oxide Powder coating Corrosion protection

Analysis of φ-divergence for Loglinear Models with Constraints under Product-multinomial Sampling

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Acta Mathematicae Applicatae Sinica 2013年第1期29卷 93-104页

作者： Ying-hua jiN yao-hua Wu Department of Statistics and Finance University of Science and Technology of China Faculty of Applied Mathematics Guangdong University of Technology

The loglinear model under product-multinomial sampling with constraints is considered. The asymptotic expansion and normality of the restricted minimum C-divergence estimator （RMDE） which is a generalization of the maximum likelihood estimator is presented. Then various statistics based on C-divergence and RMCDE are used to test various hypothesis test problems under the model considered. These statistics contain the classical loglikelihood ratio test statistics and Pearson chi-squared test statistics. Ia the last section, a simulation study is implemented.

关键词： loglinear model product-multinomial sampling Restricted minimum C-divergence estimator(RMDE) C-divergence test statistics

Naturally Occurring Parkinson’s Disease Raises the Need for Nonhuman Primates in Neurodegenerative Diseases Research

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Neuroscience Bulletin 2021年第8期37卷 1267-1269页

作者： Yuxuan yao ji Dai CAS Key Laboratory of Brain Connectome and Manipulation The Brain Cognition and Brain Disease InstituteShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research InstitutionsShenzhen518055China University of Chinese Academy of Sciences Beijing100049China

Parkinson’s disease(PD)is a common neurodegenerative disorder that affects millions of people[1].Typical symptoms of FD include bradykinesia,rigidity,resting tremor,and postural instability[1].Therefore,PD severely a... 详细信息

关键词： degenerative rigidity tremor

Properties of Titanium isotopes in complex momentum representation within relativistic mean-field theory

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Nuclear Science and Techniques 2022年第9期33卷 93-100页

作者： Tai-hua Heng yao-Wu Chu School of Physics and Optoelectronic Engineering Anhui UniversityHefei 230601China

The self-consistent quadruple potential is deduced within the relativistic mean-field(RMF)framework and substituted into the Hamiltonian,which is calculated using the complex momentum representation(CMR).Considering even-even titanium isotopes as an example,this study investigated various properties,including the resonant states of neutron-rich nuclei in the RMF-CMR model,and used them to describe the binding *** abrupt decrease in the two-neutron separation energy(S_(2n))corresponds to the traditional magic *** resonant and bound states are simultaneously exposed in the complex moment plane,where the continuum is along the integration *** four oblate neutron-rich nuclei^(72-78)Ti are weakly bound or resonant because their Fermi energies are approximately 0 *** root-meansquare(RMS)radii of these nuclei increase suddenly compared with those of others(neutron number N<48).Moreover,^(78)Ti and^(76)Ti are determined as drip-line nucleons by the value of S_(2n) and the energy levels,***,the weak-bounded character can be represented by diffuse density probability distributions.

关键词： Resonant states Self-consistent potential Complex momentum representation

Tidal evolution of exo-planetary systems:WASP-50,GJ 1214 and CoRoT-7

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Science China(Physics,Mechanics & Astronomy) 2012年第5期55卷 872-879页

作者： DONG yao ji jiangHui purple Mountain Observatory Chinese Academy of SciencesNanjing 210008China Graduate University of Chinese Academy of Sciences Beijing 100049China

We perform numerical simulations to investigate tidal evolution of two single-planet systems, that is, WASP-50 and GJ 1214 and a two-planet system CoRoT-7. The results of orbital evolution show that tidal decay and circularization may play a significant role in shaping their final orbits, which is related to the initial orbital data in the simulations. For GJ 1214 system, different cases of initial eccentricity are also considered as only an upper limit of its eccentricity （0.27） is shown, and the outcome suggests a possible maximum initial eccentricity （0.4） in the adopted dynamical model. Moreover, additional runs with alternative values of dissipation factor Q＇I are carried out to explore tidal evolution for GJ 1214b, and these results further indicate that the real Q＇1 of GJ 1214b may be much larger than its typical value, which may reasonably suggest that GJ 1214b bears a present-day larger eccentricity, undergoing tidal circularization at a slow rate. For the CoRoT-7 system, tidal forces make two planets migrating towards their host star as well as producing tidal circularization, and in this process tidal effects and mutual gravitational interactions are coupled with each other. Various scenarios of the initial eccentricity of the outer planet have also been done to investigate final planetary configuration. Tidal decay arising from stellar tides may still work for each system as the eccentricity decreases to zero, and this is in association with the remaining lifetime of each planet used to predict its future.

关键词： extrasolar planets tidal decay planetary formation numerical simulations

Probing the mechanosensitivity in cell adhesion and migration: Experiments and modeling

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Acta Mechanica Sinica 2013年第4期29卷 469-484页

作者： Bao-hua ji Bo Huo Biomechanics and Biomaterials Laboratory School of Aerospace Engineering Beijing Institute of Technology

Cell adhesion and migration are basic physiolog- ical processes in living organisms. Cells can actively probe their mechanical micro-environment and respond to the ex- ternal stimuli through cell adhesion. Cells need to move to the targeting place to perform function via cell migration. For adherent cells, cell migration is mediated by cell-matrix adhesion and cell-cell adhesion. Experimental approaches, especially at early stage of investigation, are indispensable to studies of cell mechanics when even qualitative behaviors of cell as well as fundamental factors in cell behaviors are unclear. Currently, there is increasingly accumulation of ex- perimental data of measurement, thus a quantitative formula- tion of cell behaviors and the relationship among these fun- damental factors are highly needed. This quantitative under- standing should be crucial to tissue engineering and biomed- ical engineering when people want to accurately regulate or control cell behaviors from single cell level to tissue level. In this review, we will elaborate recent advances in the ex- perimental and theoretical studies on cell adhesion and mi- gration, with particular focuses laid on recent advances in experimental techniques and theoretical modeling, through which challenging problems in the cell mechanics are sug- gested.

关键词： Cell mechanics ~ Cell adhesion. Cell migration.Modeling ~ Mechanobiology

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Deep forest

National Science Review 2019年第1期6卷 74-86页

作者： Zhi-hua Zhou ji Feng National Key Laboratory for Novel Software Technology Nanjing University

Current deep-learning models are mostly built upon neural networks, i.e. multiple layers of parameterized differentiable non-linear modules that can be trained by backpropagation. In this paper, we explore the possibility of building deep models based on non-differentiable modules such as decision trees. After a discussion about the mystery behind deep neural networks, particularly by contrasting them with shallow neural networks and traditional machine-learning techniques such as decision trees and boosting machines,we conjecture that the success of deep neural networks owes much to three characteristics, ***-by-layer processing, in-model feature transformation and sufficient model complexity. On one hand,our conjecture may offer inspiration for theoretical understanding of deep learning; on the other hand, to verify the conjecture, we propose an approach that generates deep forest holding these characteristics. This is a decision-tree ensemble approach, with fewer hyper-parameters than deep neural networks, and its model complexity can be automatically determined in a data-dependent way. Experiments show that its performance is quite robust to hyper-parameter settings, such that in most cases, even across different data from different domains, it is able to achieve excellent performance by using the same default setting. This study opens the door to deep learning based on non-differentiable modules without gradient-based adjustment, and exhibits the possibility of constructing deep models without backpropagation.

关键词： deep forest deep learning machine learning ensemble methods decision trees

A SAR Image Segment Method Using Gray Level Reduction Based on Graph in ICA Space

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Chinese Journal of Electronics 2017年第4期26卷 883-888页

作者： ji jian LYU Xiaojia yao Yafeng School of Computer Science and Technology Xidian University Netease Group

This paper proposes a new SAR image segmentation method based on graph and gray level reduction in Independent component analysis(ICA) space. Firstly,according to the grayscale information of SAR image, effective use of gray level reduction for initial segmentation can group the pixels with same or similar values to the same homogeneous region, which can address the problem of over-segmentation. Secondly, the features of regions are extracted in ICA space, and then the similarity degree can be calculated by Euclidean distance. The initial regions are merged in fully connected graph based on minimum spanning tree in ICA space. The process of region merging is divided into two phases; the first phrase is merging the different regions with the largest similarity degree, the second will focus on updating the fully connected graph for iteration. Finally, experimental and comparative results on synthetic and real SAR images verify the efficiency of the proposed algorithm.

关键词： SAR image segmentation Gray level reduction Independent component analysis(ICA) space Fully connected graph