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Synthesis, Anti-lung Cancer Activity and Docking Study of New Organic Compounds

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Chinese Journal of Structural Chemistry 2020年第6期39卷 1119-1125页

作者： li di Inner Mongolia University for Nationalities Tongliao 028000China

Novel organic compounds(1~8) were designed, synthesized and characterized by IR, ~1H NMR, H RMS, and single-crystal X-ray crystallography. The anticancer activities of these compounds were investigated against four human lung cancer cells(H20, H2227, H69 and H524) by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide(MTT) assay. Furthermore, by taking compounds 1 and 5 as representatives, molecular docking studies supported the biological assay data, suggesting that compared with 1, compound 5 has stronger interaction with protein.

关键词： MTT assay anticancer activity molecular docking

Anti-lung Cancer Activity and Docking Study of Two Novel Isochroman Derivatives

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Chinese Journal of Structural Chemistry 2020年第5期39卷 901-907页

作者： li di Inner Mongolia University for Nationalities Tongliao 028000China

Two new isochroman derivatives(1 and 2)were isolated from the fermentation products of mangrove endophytic fungus Phomopsis sp.33#.Their structures were characterized by IR,~1 H NMR,H RMS,and single-crystal X-ray *** anticancer activity of the two compounds was investigated against four human lung cancer cells(NCI-H292,NCI-H460,LTEP-A-2 and MSTO-211)by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide(MTT)***,molecular docking studies supported the biological assay data,showing that compared with 1,compound 2 has stronger interaction with protein.

关键词： isochroman derivatives anticancer activity MTT assay molecular docking

NUMERICAL ANALYSIS OF MINDliN SHELL BY MESHLESS LOCAL PETROV-GALERKIN METHOD

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Acta Mechanica Solida Sinica 2008年第2期21卷 160-169页

作者： di li Zhongqin li Shuhui li School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200030 China School of Transportation and Vehicle Engineering Shandong University of Technology Zibo 255049 China

The objectives of this study are to employ the meshless local Petrov-Galerkin method （MLPGM） to solve three-dimensional shell problems. The computational accuracy of MLPGM for shell problems is affected by many factors, including the dimension of compact support domain, the dimension of quadrture domain, the number of integral cells and the number of Gauss points. These factors＇ sensitivity analysis is to adopt the Taguchi experimental design technology and point out the dimension of the quadrature domain with the largest influence on the computational accuracy of the present MLPGM for shells and give out the optimum combination of these factors. A few examples are given to verify the reliability and good convergence of MLPGM for shell problems compared to the theoretical or the finite element results.

关键词： meshless methods meshless local Petrov-Galerkin method moving least square shell

h-ADAPTIVE ANALYSIS BASED ON MESHLESS LOCAL PETROV-G ALERKIN METHOD WITH B SPliNE WAVELET FOR PLATES AND SHELLS

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Acta Mechanica Solida Sinica 2009年第4期22卷 337-346页

作者： di li Zhongqin lin School of Transportation and Vehicle Engineering Shandong University of Technology Zibo 255049 China School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200030 China

Using the two-scale decomposition technique, the h-adaptive meshless local Petrov- Galerkin method for solving Mindlin plate and shell problems is presented. The scaling functions of B spline wavelet are employed as the basis of the moving least square method to construct the meshless interpolation function. Multi-resolution analysis is used to decompose the field variables into high and low scales and the high scale component can commonly represent the gradient of the solution according to inherent characteristics of wavelets. The high scale component in the present method can directly detect high gradient regions of the field variables. The developed adaptive refinement scheme has been applied to simulate actual examples, and the effectiveness of the present adaptive refinement scheme has been verified.

关键词： meshless methods meshless local Petrov-Galerkin method multi-resolution analysis adaptive analysis plate and shell

COMPUTE A CEliS-DENNIS-TAPIA STEP

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Journal of Computational Mathematics 2005年第5期23卷 463-478页

作者： Gai-di li Ya-xiang Yuan College of Applied Sciences Beijing University of Technology Beijing 100022China LSEC ICMSECAcademy of Mathematics and System SciencesChinese Academy of Sciences Beijing 100080China

In this paper, we present an algorithm for the CDT subproblem. This problem stems from computing a trust region step of an algorithm, which was first proposed by Celis, Dennis and Tapia for equality constrained optimization. Our algorithm considers general case of the CDT subproblem, convergence of the algorithm is proved. Numerical examples are also provided.

关键词： The CDT subproblem Local solution Global solution Dual function

Key Technology of Embedded System Implementation for Software-based CNC System

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Chinese Journal of Mechanical Engineering 2010年第2期23卷 217-224页

作者： WAN Jiafu li di ZHANG Ping College of Computer Science and Engineering South China University of Technology Guangzhou 510006 China School of Mechanical and Automotive Engineering South China University of Technology Guangzhou 510640 China Department of Computer Guangdong College of Mechanical and Electrical Technology Guangzhou 510515 China

The software-based computer numerical control（CNC） system includes three types of tasks： periodic real-time tasks, aperiodic real-time tasks, and non-real-time tasks. The tasks are characterized by concurrency, hybridization, and correlation, which make system implementation difficult. The conventional scheduling algorithm can not meet the demands of system implementation in the software-based CNC system completely. The uncertainty factors when running real-time tasks affect control performance by degrading manufacturing accuracy as a result of system resource and processor use restrictions. To address the technical difficulty of embedded system implementation, a novel fuzzy feedback scheduling algorithm based on output jitter of key real-time tasks for a software-based CNC system is proposed. Time characteristics, such as sampling jitter, input-output jitter, and non-schedulability are discussed, followed by quantification through simulations of the impact of time characteristics on manufacturing accuracy. On the basis of this research, the scheduler architecture is designed, and then the algorithm table is calculated. When the system resource changes, the key periodic real-time tasks meet their deadlines by means of dynamically adjusting the task period. The simulated results show that the machining precision rises by an order of magnitude for the proposed scheduler in resource-constrained software-based CNC systems. Moreover, unlike conventional feedback scheduling methods, the algorithm in this paper does not rely on the availability of task execution times and is easy to implement while incurring only a small overhead.

关键词： software-based CNC system embedded system implementation output jitter fuzzy feedback scheduling manufacturing accuracy

Forward modeling for “earth-ionosphere” mode electromagnetic field

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Journal of Central South University 2016年第9期23卷 2305-2313页

作者： li di-quan Key Laboratory of Metallogenic Prediction of Nonferrous Metals of Ministry of Education (Central South University) Changsha 410083 China School of Geosciences and Info-Physics Central South University Changsha 410083 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

A fixed artificial source(greater than 200 kW) was used and the source location was selected at a high resistivity region to ensure high emission efficiency. Some publications used the "earth-ionosphere" mode in modeling the electromagnetic(EM) fields with the offset up to a thousand kilometer, and such EM fields still have a signal/noise ratio of 10-20 dB. This means that a new EM method with fixed source is feasible, but in their calculation, the displacement in air was neglected. In this work, some three-layer modeling results were presented to illustrate the basic EM fields' characteristics in the near, far and waveguide areas under "earth-ionosphere" mode, and a standard is given to distinguish the boundary of near, far and waveguide areas. Due to the influence of the ionosphere and displacement current in the air, the "earth-ionosphere" mode EM fields have an extra waveguide zone, where the fields' behavior is very different from that of the far field zone.

关键词： earth-ionosphere mode large power large offset electromagnetic field forward modeling

Machine learning for nanohertz gravitational wave detection and parameter estimation with pulsar timing array

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Science China(Physics,Mechanics & Astronomy) 2020年第12期63卷 92-101页

作者： MengNi Chen YuanHong Zhong Yi Feng di li Jin li College of Physics Chongqing UniversityChongqing 401331China School of Microelectronics and Communication Engineering Chongqing UniversityChongqing 400044China National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China University of Chinese Academy of Sciences Beijing 100049China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China NAOC-UKZN Computational Astrophysics Centre University of Kwa Zulu-NatalDurban 4000South Africa

Studies have shown that the use of pulsar timing arrays(PTAs)is among the approaches with the highest potential to detect very low-frequency gravitational waves in the near *** the capture of gravitational waves(GWs)by PTAs has not been reported yet,many related theoretical studies and some meaningful detection limits have been *** this study,we focused on the nanohertz GWs from individual supermassive binary black *** specific pulsars(PSR J1909-3744,PSR J1713+0747,PSR J0437-4715),the corresponding GW-induced timing residuals in PTAs with Gaussian white noise can be ***,we report the classification of the simulated PTA data and parameter estimation for potential GW sources using machine learning based on neural *** a classifier,the convolutional neural network shows high accuracy when the combined signal to noise ratio≥1.33 for our simulated ***,we applied a recurrent neural network to estimate the chirp mass(M)of the source and luminosity distance(Dp)of the pulsars and Bayesian neural networks(BNNs)to obtain the uncertainties of chirp mass *** of the uncertainties is crucial to astrophysical *** our case,the mean relative error of chirp mass estimation is less than 13.6%.Although these results are achieved for simulated PTA data,we believe that they will be important for realizing intelligent processing in PTA data analysis.

关键词： machine learning neural network PTA GW-induced time residuals

A Numerical Method for Rigid-plastic FEM Analysis Basing on Mathematical Programming

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上海交通大学学报 2004年第z2期38卷 32-37页

作者： li di lin Zhongqin Chen Guanlong Zhang Weigang li Shuhui School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China Shandong University of Technology Zibo PR China School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China

The rigid-plastic analysis of mental forming simulation is formulated as a discrete nonlinear mathematical programming problem with equality and inequality constraints by means of the finite element technique. An iteration algorithm is used to solve this formulation, which distinguishes the integration points of the rigid zones and the plastic zones and solves a series of the quadratic programming to overcome the difficulties caused by the nonsmoothness and the nonlinearity of the objective function. This method has been used to carry out the rigid-plastic FEM analysis. An example is given to demonstrate the effectiveness of this method.

关键词： rigid-plastic mathematical programming finite element method