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ON CONTRACTION AND SEMI-CONTRACTION FACTORS OF GSOR METHOD FOR AUGMENTED LINEAR SYSTEMS

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Journal of Computational Mathematics 2010年第6期28卷 901-912页

作者： Fang Chen Yao-Lin jiang Bing Zheng Department of Mathematical Sciences Xi'an Jiaotong University Xi'an 710049 China School of Science Xi'an University of Post and Telecommunications Xi'an 710121 China Department of Mathematical Sciences Xi ' an Jiaotong University Xi ' an 710049 China School of Mathematics and Statistics Lanzhou University Lanzhou 730000 China

The generalized successive overrelaxation （GSOR） method was presented and studied by Bai, Parlett and Wang [Numer. Math. 102（2005）, pp.1-38] for solving the augmented system of linear equations, and the optimal iteration parameters and the corresponding optimal convergence factor were exactly obtained. In this paper, we further estimate the contraction and the semi-contraction factors of the GSOR method. The motivation of the study is that the convergence speed of an iteration method is actually decided by the contraction factor but not by the spectral radius in finite-step iteration computations. For the nonsingular augmented linear system, under some restrictions we obtain the contraction domain of the parameters involved, which guarantees that the contraction factor of the GSOR method is less than one. For the singular but consistent augmented linear system, we also obtain the semi-contraction domain of the parameters in a similar fashion. Finally, we use two numerical examples to verify the theoretical results and the effectiveness of the GSOR method.

关键词： Contraction and semi-contraction factors, Augmented linear system, GSOR method Convergence.

Integrated Network Pharmacology and Antioxidant Activity?Guided Screen System to Exploring Antioxidants and Quality Markers of Shunaoxin Pills against Chronic Cerebral Ischemia

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World Journal of Traditional Chinese Medicine 2019年第1期5卷 1-8页

作者： Nian-Wei Chang Dan-Dan cheng Jia-Nan Ni Ying-Ying Guo Guang-Cui Chu Unchol Kim Min jiang Gang Bai Graduate School Tianjin University of Traditional Chinese Medicine Department of Genetic Engineering State Academy of SciencePyongyang Democratic People's Republic of Korea College of Pharmacy State Key Laboratory of Medicinal Chemical Biology Tianjin Key Laboratory of Molecular Drug Research Nankai University

Objective: The main objective of the study is to screen the quality markers(Q-markers) for relieving oxidative stress damage and against chronic cerebral ischemia in Shunaoxin pills(SNX). Methods: The benefit effect of SNX was evaluated by a rat chronic cerebral ischemia model. The main ingredients of SNX were identified by ultra-performance liquid chromatography-quadrupole time-of-flight, whereas its core targets and pathways around antioxidative stress were predicted by Pharm Mapper and kyoto encyclopedia of genes and genomes(KEGG) analysis. Moreover, the antioxidants were screened by high-performance liquid chromatography with postcolumn derivatization system and then representative ingredients were verified by cell experiments. Results: SNX could increase expression of catalase and superoxide dismutase(SOD) as well as antagonize oxidative damage in the brain. The effects may be related to three types of antioxidant pathways, including nitrogen metabolism, arachidonic acid metabolism, and the cyclic guanosine monophosphate-dependent protein kinase(c GMP-PKG) signaling pathway by multiple active components regulate targets. Among them, ferulic acid and ligustilide were shown the key scavenging ability for reactive oxygen free radicals and significantly increased the contents of nitric oxide(NO), NO synthase, and SOD as well as decreased malonaldehyde. Conclusion: The oxidation resistances of biological and chemical processes in SNX to protect against cerebral oxidative stress injury were preliminary revealed by an integrated network pharmacology and antioxidant activity-guided screen system. Ferulic acid and ligustilide played a major antioxidant role that could be used as Q-markers to control the quality of SNX.

关键词： Antioxidant chronic cerebral ischemia network pharmacology Q-markers Shunaoxin pills

Contact Mechanism of the Ag-doped Trimolybdate Nanowire as An Antimicrobial Agent

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Nano-Micro Letters 2012年第4期4卷 228-234页

作者： Yujie jiang Jian Gang Sheng-Yong Xu Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics Peking University

Antibacterial Ag-agents are intensively applied as broad spectrum, high-stability, high-efficiency and high-safety inorganic antibacterial agents. We have developed a new kind of antibacterial Ag-agent, namely Ag_2-x(NH_4)xMo_3O_(10) ·3H_2O nanowires(NWs). Carrying Ag atoms in the lattice and Ag-rich nanoparticles on the surface, the Ag-doped NWs show strong antibacterial effects for a variety of bacteria including ***, Staphylococcus aureus, Candida albicans and Aspergil lus niger. By performing systematic comparison experiments, we have proven that the main antibacterial effects are neither resulted from the tiny amount of Ag+ions released from the Ag-doped NWs in aqueous solutions, nor resulted from Ag-rich nanoparticles of fragments of the NWs when they are slowly dissolved in the Martin broth. Instead, the effects are mainly resulted from a contact mechanism, under which, the Ag-doped NWs need to be physically in contact with the bacteria to be eliminated. This is a novel phenomenon observed in the interactions between nanomaterials and live cells, which is worthy of further investigation at the molecular scale. As the Ag-doped NWs are not dissolved in pure water or weak acids, one may find practical antibacterial applications in textile industry and food storage industry for these unique nanomaterials.

关键词： Antibacterial agent Antibacterial Ag-agent Silver ions Silver-rich nanoparticles Silver-doped trimolybdate nanowire Bio-safety of nanomaterials Contact mechanism

Probing surface structure on two-dimensional metal-organic layers to understand suppressed interlayer packing

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Nano Research 2020年第11期13卷 3151-3156页

作者： Peican Chen Yi Liu Xuefu Hu Xiaolin Liu En-Ming You Xudong Qian Jiawei Chen Liangping Xiao Lingyun Cao Xinxing Peng Zhongming Zeng Yibing jiang Song-Yuan Ding Honggang Liao Zhaohui Wang Da Zhou cheng Wang IChem State Key Laboratory of Physical Chemistry of Solid SurfacesCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China School of Mathematical Sciences and Fujian Provincial Key Laboratory of Mathematical Modeling and High-Performance Scientific Computation Xiamen UniversityXiamen361005China

Two-dimensional metal-organic layers(MOLs)from alternatively connected benzene-tribenzoate ligands and Zr6(μ3-O)_(4)(μ3-OH)_(4) or Hf6(μ3-O)_(4)(μ3-OH)_(4) secondary building units can be prepared in gram scale via solvothermal ***,the reason why the monolayers did not pack to form thick crystals is *** we investigated the surface structure of the MOLs by a combination of sum-frequency generation spectroscopy,nanoscale infrared microscopy,atomic force microscopy,aberration-corrected transmission electron microscopy,and compositional *** found a partial coverage of the monolayer surface by dangling tricarboxylate ligands,which prevent packing of the *** finding illustrates low-density surface modification as a strategy to prepare new two-dimensional materials with a high percentage of exposed surface.

关键词： metal-organic frameworks metal-organic layers surface structure two-dimensional(2D)materials solvothermal synthesis

Two Cu(Ⅱ)and Co(Ⅱ)-based Coordination Polymers Based on the N,S-donor Ligand:Crystal Structures and Anticancer Activity Evaluation

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Chinese Journal of Structural Chemistry 2020年第10期39卷 1849-1854,1744页

作者： LI Jing LI jiang-Tao Key Laboratory for Surface Engineering and Remanufacturing in Shaanxi Province School of Chemical EngineeringXi'an UniversityXi'an 710065China

Two new Cu(II)and Co(II)-based coordination polymers with the chemical formulae of{Cu(L)2]·DMF}n(1)and{[Co(L)2]·2DMF}n(2)have been successfully constructed from a pyridine-substituted N-heterocyclic thioamide ligand,namely[3,4?-bipyridine]-2?-thiol(HL).Complex 1 is composed of two identical coordination networks with dia topology interpenetrating into each other,and shows 1-D microporous channels along the a *** 2 is assembled by 2-D square-grid layers stacked in an eclipsed fashion to give 1-D large square channels along the b ***-8 was used for the detection of cancer *** indicated that compound 1 exhibited stronger anti-cancer activity than compound 2 on the H1650 cancer *** Annexin V-FITC/PI was recommended for cancer cell apoptosis,and the western blot was applied for the detection of PI3K/AKT pathway activation.

关键词： coordination polymer N S-donor ligand CCK-8 assay anticancer activity

Studying the Fermi GeV light curve of Vela with the two-pole caustic model

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Research in Astronomy and Astrophysics 2009年第12期9卷 1324-1330页

作者： Huan Yu Jun Fang Ze-Jun jiang Department of Physics Yunnan University Kunming 650091 China

An observation of the Vela pulsar with the Fermi Large Area Telescope has been recently reported and the GeV light curve shows two main peaks with a phase separation of ～0.43. We study the GeV light curve using the two-pole caustic model in which the peaks of the light curves of the pulsar result from caustic effects. The results show that the two-pole caustic model can reproduce the observed emission pattern of the two peaks and the bridge emission between them well, but overestimates the flux outside the two peaks. After taking account of the pair production effect on the azimuthal angle, we find that the resulting light curve is more consistent with the observation. We excluded the emissions from the field lines for which the distance from the null charge surface, where the pairs can be significantly produced, is larger than the radius of the light cylinder.

关键词： gamma rays: theory -- pulsars: individual (PSR B0833-45)

Role of hydrogen in China's energy transition towards carbon neutrality target:IPAC analysis

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Advances in Climate Change Research 2023年第1期14卷 43-48页

作者： Pian-Pian XIANG Chen-Min HE Sha CHEN Wei-Yi jiang Jia LIU Ke-Jun jiang College of Energy and Environment Beijing University of TechnologyBeijing 100124China Zhejian Carbon Neutral Innovation Institute Zhejiang University of TechnologyHangzhou 310014China Graduate School of International Studies Yonsei UniversitySeoul 03722South Korea Renm Consulting Co. Beijing 100038China Energy Research Institute Chinese Academy of Macro-Economic ResearchBeijing 100038China

China announced its intention to achieve carbon neutrality by 2060 in 2020,and there is an urgent need to understand the viability of emission pathways to reach this *** study presents the IPAC modelling team's scenario analysis on China's hydrogen utilisation as a key option for carbon neutrality *** contrast to other studies,this study examines the demand for hydrogen as a feedstock and process material in the industrial sector and as a source of energy in the transportation sector in relation to China's energy system *** process of manufacturing hydrogen from carbon-free power generation was also *** finding indicates that the demand for hydrogen could reach 52.4 Mt by 2050 and that the hydrogen will come from renewable power generation and nuclear energy,increasing the demand for electricity by 1884.8 TW *** are several regions in China with abundant renewable energy and low power generation costs,which will make the hydrogen-based industry competitive in these regions after 2035.

关键词： Scenario Hydrogen Carbon neutrality targets CO_(2)mitigation China

DRIB:Interpreting DNN with Dynamic Reasoning and Information Bottleneck

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国际计算机前沿大会会议论文集 2022年第1期 178-189页

作者： Yu Si Keyang cheng Zhou jiang Hao Zhou Rabia Tahir School of Computer Science and Communication Engineering Jiangsu UniversityZhenjiang 212013China

The interpretability of deep neural networks has aroused widespread concern in the academic and industrial *** paper proposes a new method named the dynamic reasoning and information bottleneck(DRIB)to improve human interpretability and *** the method,a novel dynamic reasoning decision algorithmwas proposed to reduce multiply accumulate operations and improve the interpretability of the *** information bottleneck was introduced to the DRIB model to verify the attribution correctness of the dynamic reasoning *** DRIB reduces the burden approximately 50%by decreasing the amount of *** addition,DRIB keeps the correct rate at approximately 93%.The information bottleneck theory verifies the effectiveness of this method,and the credibility is approximately 85%.In addition,through visual verification of this method,the highlighted area can reach 50%of the predicted area,which can be explained more *** experiments prove that the dynamic reasoning decision algorithm and information bottleneck theory can be combined with each ***,the method provides users with good interpretability and understandability,making deep neural networks trustworthy.

关键词： Dynamic reasoning Information bottleneck Interpreting DNNs

CUSP CATASTROPHE MODEL OF INSTABILITY OF PILLAR IN ASYMMETRIC MINING

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Applied Mathematics and Mechanics(English Edition) 2005年第8期26卷 1100-1106页

作者： LI jiang-teng（李江腾） CAO Ping（曹平） School of Resources and Safety Engineering Central South University Changsha 410083 P. R. China Civil Engineering Department Hunan Polytechnic University Zhuzhou 412008 Hunan Province P. R. China

A simplified mechanical model of pillar-hang wall was established in asymmetric mining and instability of the system was discussed by means of potential energy principle and cusp catastrophe theory. The necessary-sufficient condition and the jump value of displacement of pillar and the released energy expressions were derived, which established foundation for quantifying of the instability of system. The results show that instability of the system is related to load and its stiffness distribution. The critical load increases with the increasing relative stiffness, and the system is more stable. On the contrary, the instability of system is likely to occur, and the released energy is larger in instability process, and the harm is more tremendous accordingly. Furthermore, an example was calculated, and the estimated results are in good agreement with the practical experience, which provide basis for mining order and arranging stope.

关键词： pillar stability potential energy cusp catastrophe asymmetric mining