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ON THE DIVIDED DIFFERENCE FORM OF FAA DI BRUNO＇S FORMULA

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Journal of Computational Mathematics 2006年第4期24卷 553-560页

作者： xing-hua wang He-yu wang Department of Mathematics Zhejiang University Hangzhou 310028 China Computer Science School Zhejiang University Hangzhou 310027 China Mathematics Department of Hong Kong Baptist University Kowloon Hong Kong

The n-divided difference of the composite function h ：= f o g of functions f, g at a group of nodes t0,t1,…,tn is shown by the combinations of divided differences of f at the group of nodes g（t0）,g（t1）,…,g（tm） and divided differences of g at several partial group of nodes t0,t1,…,tn, where m = 1,2,…,n. Especially, when the given group of nodes are equal to each other completely, it will lead to Faà di Bruno＇s formula of higher derivatives of function h.

关键词： Divided difference Newton interpolation Composite function FAA di Bruno's formula Bell polynomial

On the Hermite interpolation

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Science China Mathematics 2007年第11期50卷 1651-1660页

作者： xing-hua wang Department of Mathematics Zhejiang UniversityHangzhou 310027China

Explicit representations for the Hermite interpolation and their derivatives of any order are ***,suppose that the interpolated function f has continuous derivatives of sufficiently high order on some sufficiently small neighborhood of a given point x and any group of nodes are also given on the *** the derivatives of any order of the Hermite interpolation polynomial of f at the point x are applied to approximating the corresponding derivatives of the function f(x),the asymptotic representations for the remainder are presented.

关键词： Hermite interpolation cycle index numerical differentiation explicit representation remainder

Prospects of microwave-induced thermoacoustic imaging

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电子科技学刊:英文版 2023年第3期21卷 21-37页

作者： xing-hua wang huan Qin Key Laboratory of Laser Life Science(Ministry of Education)&Institute of Laser Life Science College of BiophotonicsSouth China Normal UniversityGuangzhou510631China Guangdong Provincial Key Laboratory of Laser Life Science College of BiophotonicsSouth China Normal UniversityGuangzhou510631China Guangzhou Key Lab of Spectral Analysis and Functional Probes College of BiophotonicsSouth China Normal UniversityGuangzhou510631China

Microwave-induced thermoacoustic imaging(MTAI)has advantages including the large imaging depth,high imaging resolution,high imaging contrast,and fast imaging *** thermoacoustic(TA)group of South China Normal University has dedicated to developing TA imaging for more than a decade and has made many *** review introduces these breakthroughs from two aspects including the improvement in techniques and the exploration of *** the technological level,there are ultrashort microwave pulse(USMP)-induced􀀁TA imaging that can improve the imaging resolution,nonlinear thermoacoustic imaging(NTAI)that can improve the imaging contrast,polarized microwave-induced􀀁thermoacoustic imaging(P-MTAI)that can obtain cellular-level alignment information,and more convenient and accurate handheld and multimodal *** the application side,the optimization and expansion have been carried out,mainly concentrating on breast and myocardial ***,several current research directions are introduced,including the application of P-MTAI on joint imaging and research on whole-body imaging of small animals.

关键词： Applications in biomedical field Microwave-induced thermoacoustic imaging(MTAI) Nonlinear thermoacoustic imaging(NTAI) Polarized microwave-induced thermoacoustic imaging(P-MTAI) Ultrashort microwave pulse (USMP)-induced thermoacoustic imaging

The Iyengar Type Inequalities with Exact Estimations and the Chebyshev Central Algorithms of Integrals

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Acta Mathematica Sinica,English Series 2005年第6期21卷 1361-1376页

作者： xing hua wang Shi Jun YANG Department of Mathematics Zhejiang University Hangzhou 310028 P. R. China College of Mathematics and Information Science Wenzhou University Zheiianq 325200 P R China Department of Mathematics Hangzhou Normal College Hangzhou 310012 P. R. China

In this paper, both low order and high order extensions of the Iyengar type inequality are obtained. Such extensions are the best possible in the same sense as that of the Iyengar inequality. hzrthermore, the Chebyshev central algorithms of integrals for some function classes and some related problems are also considered and investigated.

关键词： Iyengar inequality Chebyshev center Best quadrature formula Best interpolation Nikol-skii type estimations

Numerical investigation of the convex effect on the behavior of crossing excavations

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第10期12卷 747-757页

作者： Min ZHANG xing-hua wang Guang-cheng YANG You wang School of Civil Engineering Central South University Changsha 410075 China

A 3D numerical model considering the soil-structure interaction is presented in this paper to examine the ground movement and internal force during the construction of Qingdao North Metro Station, China with a special focus on the convex effect of the crossing excavation. The influence of intersection angles and soil resilience characteristics on deformation behavior is discussed, and the suitability of two alternative constitutive models applied in excavation simulation is also considered. The analysis results show that a notable convex effect appears to be associated with the crossing excavation, and the intersection is the key area requiring special attention. The displacements at the comer decrease with increasing crossing angles. The axial loads of struts along the retaining pile wall are unequal, and the values near the cross section are generally larger than the average loads of the left-sided ones. The modified Cam-Clay （MCC） model, which is capable of describing the loading-unloading criterion and identifying the stiffness difference of strain hardening between loading and unloading, can yield a relatively high accuracy of estimation for the behavior of excavations in comparison to the Mohr-Coulomb （MC） model. Furthermore, slight soil deformation resilience after unloading can reduce the ground surface settlement and enhance the ground stability.

关键词： Crossing excavation Convex effect Constitutive model Numerical simulation

Explicit Representations for Local Lagrangian Numerical Differentiation

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Acta Mathematica Sinica,English Series 2007年第2期23卷 365-372页

作者： He Yu wang Feng CUI xing hua wang Computing Center Zhejiang University Department of Mathematics Hong Kong Baptist University Department of Mathematics Zhejiang University

It is shown that in Lagrangian numerical differentiation formulas, the coefficients are explicitly expressed by means of cycle indicator polynomials of symmetric group. Moreover, asymptotic expansions of the remainders are also explicitly represented as a fixed number of interpolation nodes approaching infinitely to the point at which the derivative is evaluated. This implies that complete explicit formulas for local Lagrangian numerical differentiation can be obtained.

关键词： numerical differentiation explicit representation local estimate symmetric group cycle indicator

Hydrogen and syngas production from two-step steam reforming of methane using CeO_2 as oxygen carrier

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Journal of Natural Gas Chemistry 2011年第3期20卷 281-286页

作者： xing Zhu, hua wang YonggangWei Kongzhai Li Xianming Cheng Engineering Research Center of Metallurgical Energy Conservation and Emission Reduction Ministry of Education Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology Kunming 650093 Yunnan China

CeO2 oxygen carrier was prepared by precipitation method and tested by two-step steam reforming of methane （SRM）. Two-step SRM for hydrogen and syngas generation is investigated in a fixed-bed reactor. Methane is directly converted to syngas at a H2/CO ratio close to 2 ： 1 at a high temperature （above 750 °C） by the lattice oxygen of CeO2; methane cracking is found when the reduction degree of CeO2 was above 5.0% at 850 °C in methane isothermal reaction. CeO2？δ obtained from methane isothermal reaction can split water to generate CO-free hydrogen and renew its lattice oxygen at 700 °C; simultaneously, deposited carbon is selectively oxidized to CO2 by steam following the reaction （C＋2H2O→CO2＋2H2）. Slight deactivation in terms of amounts of desired products （syngas and hydrogen） is observed in ten repetitive two-step SRM process due to the carbon deposition on CeO2 surface as well as sintering of CeO2.

关键词： two-step steam reforming of methane CeO2 hydrogen syngas redox cycle

Protective effect of saturated hydrogen saline against blue light-induced retinal damage in rats

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International Journal of Ophthalmology(English edition) 2012年第2期5卷 151-157页

作者： Mei Feng xing-hua wang Xiao-Bo Yang Qing Xiao and Fa-Gang Jiang Department of Ophthalmology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430022 Hubei Province China

AIM: To explore the effect of saturated hydrogen saline on blue light-induced retinal damage in rats. METHODS: The retinal damage of rats was induced by blue light exposure for 6 hours and examined 8 hours, 16 hours and 24 hours after the exposure. One hundred female Sprague-Dawley rats were randomly divided into four groups. Group 1 included 30 rats received light exposure without any other treatment. Group 2 included 30 rats received light exposure with intraperitoneal injection of normal saline. Group 3 included 30 rats received light exposure with intraperitoneal injection of saturated hydrogen saline. And Group 4 included the other 10 rats which did not receive any treatment. The amount of intraperitoneal injection of saturated hydrogen saline and normal saline was calculated in the ratio of 1ml/100g of rat weight. Specimens were collected and processed by H-E staining, ultrastructure observation, biochemical measurement. Morphological changes were observed by light microscope and transmission electron microscope (TEM) and the retinal outer nuclear layer (ONL) thickness was measured by IPP 6.0, while the malondialdehyde (MDA) was measured by colorimetric determination at 532nm. RESULTS: Although the structure of retina in Group 1 and Group 2 was injured heavily, the injury in Group 3 was mild. The differences between Group 1 and Group 2 were not significant. Compared with the rats in Group 1 and Group 2, the ones in Group 3 had more clearly demarcated retina structure and more ordered cells by light microscope and TEM observation. The ONL thicknesses (400 times) of four groups at each time point except between Group 1 and Group 2 were significantly different (P<0.05). The thicknesses of the ONL in Group 1 at three time points were 30.41 +/- 4.04 mu m, 26.11 +/- 2.82 mu m and 20.63 +/- 1.06 mu m, in Group 2 were 31.62 +/- 4.54 mu m, 25.08 +/- 3.63 mu m and 19.07 +/- 3.86 mu m, in Group 3 were 29.75 +/- 3.62 mu m, 28.83 +/- 1.97 mu m and 27.61 +/- 1.83 mu m. In G

关键词： retina hydrogen antioxidants phototoxicity

Multiscale causes of the 2022 Yangtze mega-flash drought under climate change

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Science China Earth Sciences 2024年第8期67卷 2649-2660页

作者： xing YUAN Yumiao wang Shiyu ZHOU hua LI Chenyuan LI School of Hydrology and Water Resources Nanjing University of Information Science and TechnologyNanjing 210044China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China Key Laboratory of Hydrometeorological Disaster Mechanism and Warning of Ministry of Water Resources Nanjing University of Information Science and TechnologyNanjing 210044China

The 2022 Yangtze mega-flash drought is characterized by strong intensity and rapid development both in time and space,accompanied by a persistent anticyclonic circulation ***,the causes of the extreme event remain elusive given the multiscale nature of *** we presented a brief overview for the oceanic and terrestrial causes of the megaflash drought during the summer of 2022,and estimated the risk in a changing *** the soil moisture percentile as the drought index,it was found that the drought expanded to the entire Yangtze River basin within two months,with 80%of basin under severe drought conditions at the end of *** the intensity and onset speed of the 2022 mega-flash drought were ranked as the first during the past 62 years,with return periods of 86 and 259 years,*** results of composite analysis showed that the spring La Ni?a can facilitate the abrupt change from a wet/normal condition in May–June to drought in July–August over the Yangtze River basin,which was beneficial for the increase of flash drought intensity and onset speed *** analysis through the linear regression also indicated that the unprecedented intensity was associated with the negative phase of the Pacific Decadal *** by a coupling strength index for soil moisture and vapor pressure deficit,it was found that there was a strong land-atmosphere coupling over the Yangtze River basin during July–August *** attribution by using CMIP6 climate models suggested that land-atmosphere coupling increased the risks of flash drought intensity and onset speed like 2022 by 61%±6%and 64%±7%under natural climate forcings,and the synergy of coupling and anthropogenic climate change would increase the risks by 75%±22%and 85%±12%.Our findings emphasized the role of landatmosphere coupling combined with anthropogenic climate change in intensifying flash droughts.

关键词： Flash drought Yangtze River basin Land-atmosphere coupling Climate change Attribution