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Existence Results for Functional Differential Inclusions with Infinite Delay

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Acta Mathematica Sinica,English Series 2006年第3期22卷 773-780页

作者： shi Huang hong Department of Applied Mathematics Hangzhou Dianzi University

The aim of the present paper is to investigate the existence of solutions to functional differential inclusions with infinite delay in Banach spaces. A relevant set of phase space axioms is proposed. The main tools us... 详细信息

关键词： functional differential inclusion phase space infinite delay measure of noncompactness

Permanence and periodic solutions of delayed predator-prey system with impulse

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Applied Mathematics(A Journal of Chinese Universities) 2010年第3期25卷 264-276页

作者： shi hong-bo School of Mathematical Sciences Huaiyin Normal University Jiangsu 223300 China

The existence of positive periodic solution of a generalized semi-ratio-dependent predator-prey system with time delay and impulse is studied by using the continuation theorem based on the coincidence degree theory. T... 详细信息

关键词： Predator-prey system impulse periodic solution permanence coincidence degree.

Nucleolar histone deacetylases HDT1,HDT2,and HDT3 regulate plant reproductive development

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Journal of Genetics and Genomics 2022年第1期49卷 30-39页

作者： Yu Luo Dong-Qiao shi Peng-Fei Jia Yuan Bao hong-ju Li Wei-Cai Yang State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing 100049China

Nucleolus is a membrane-less organelle where ribosomes are assembled, and ribosomal RNAs(r RNAs)transcribed and processed. The assembled ribosomes composed of ribosomal proteins and r RNAs synthesize proteins for cell survival. In plants, the loss of nucleolar ribosomal proteins often causes gametophytically or embryonically lethality. The amount of r RNAs are under stringent regulation according to demand and partially switched off by epigenetic modifications. However, the molecular mechanism for the selective activation or silencing is still unclear, and the transcriptional coordination of r RNAs and ribosomal proteins is also unknown. Here, we report the critical role of three Arabidopsis nucleolar proteins HDT1,HDT2, and HDT3 in fertility and transcription of r DNAs and r RNA processing-related genes through histone acetylation. This study highlights the important roles of transcriptional repression of ribosome biogenesisrelated genes for plant reproductive development.

关键词： Histone deacetylase rRNAs Ribosome Reproductive development

Graph Representation of Projective Resolutions

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Acta Mathematica Sinica,English Series 2011年第3期27卷 555-566页

作者： hong Bo shi Department of Mathematics Nanjing University of Finance and Economics Nanjing 210046 P. R. China

We generalize the concept -- dimension tree and the related results for monomial algebras to a more general case -- relations algebras A by bringing GrSbner basis into play. More precisely, we will describe the minimal projective resolution of a left A-module M as a rooted ＇weighted＇ diagraph to be called the minimal resolution graph for M. Algorithms for computing such diagraphs and applications as well will be presented.

关键词： Relations algebras dimension trees projective resolutions finitistic dimensions Grobner basis

Selective binding of unsaturated aliphatic hydrocarbons by a pillar[5]arene

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Chinese Chemical Letters 2013年第8期24卷 707-709页

作者： Xiao-shi Hu hong-Mei Deng Jian Li Xue-Shun Jia Chun-ju Li Department of Chemistry Shanghai University

The complexation behavior of unsaturated fatty hydrocarbons,i.e.,1,7-octadiyne and 1,7-octadiene,by a perethylated pillar[5]arene has been investigated,which was compared with that for saturated n-octane. It was found that the host-guest binding strength increased in accordance with the electron-negativity of the terminal carbon atom on the guests：alkyne〉alkene〉alkane.

关键词： Molecular recognition Pillararenes Unsaturated hydrocarbons Supramolecular chemistry

Climate effects of the GlobeLand30 land cover dataset on the Beijing Climate Center climate model simulations

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Science China Earth Sciences 2016年第9期59卷 1754-1764页

作者： shi XueLi NIE SuPing ju WeiMin YU Le National Climate Center Beijing 100081 China International Institute for Earth System Science (ESSI) Nanjing University Nanjing 210093 China Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System Science Tsinghua University Beijing 100084 China Joint Center for Global Change Studies Beijing 100875 China

Land cover is one of the most basic input elements of land surface and climate models. Currently, the direct and indirect effects of land cover data on climate and climate change are receiving increasing attentions. In this study, a high resolution(30 m) global land cover dataset(Globe Land30) produced by Chinese scientists was, for the first time, used in the Beijing Climate Center Climate System Model(BCC_CSM) to assess the influences of land cover dataset on land surface and climate simulations. A two-step strategy was designed to use the Globe Land30 data in the model. First, the Globe Land30 data were merged with other satellite remote sensing and climate datasets to regenerate plant functional type(PFT) data fitted for the BCC_CSM. Second, the up-scaling based on an area-weighted approach was used to aggregate the fine-resolution Globe Land30 land cover type and area percentage with the coarser model grid resolutions globally. The Globe Land30-based and the BCC_CSM-based land cover data had generally consistent spatial distribution features, but there were some differences between them. The simulation results of the different land cover type dataset change experiments showed that effects of the new PFT data were larger than those of the new glaciers and water bodies(lakes and wetlands). The maximum value was attained when dataset of all land cover types were changed. The positive bias of precipitation in the mid-high latitude of the northern hemisphere and the negative bias in the Amazon, as well as the negative bias of air temperature in part of the southern hemisphere, were reduced when the Globe Land30-based data were used in the BCC_CSM atmosphere model. The results suggest that the Globe Land30 data are suitable for use in the BCC_CSM component models and can improve the performance of the land and atmosphere simulations.

关键词： Land cover Climate model Application strategy Numerical simulation Air temperature Precipitation

Light absorption coefficients of ionic liquids under electric field

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Chinese Physics B 2019年第1期28卷 608-619页

作者： Ji Zhou shi-Kui Dong Zhi-hong He ju-Lius Caesar Puoza Yan-Hu Zhang Beijing Institute of Space Mechanics&Electricity School of Energy Science and Engineering Harbin Institute of Technology Department of Mechanical Engineering Sunyani Technical University Advancd Manufacturing&Equipment Institute Jiangsu University

Ionic liquids have attracted a lot of research attention for their applications in novel optoelectronic structures and devices as an optical means of regulating electricity. Although the electro-optic effect of ionic liquids is mentioned in some literature, quantitative testing and analysis are hardly found in light absorption coefficients of ionic liquids under an electric field. In the present study, an experimental apparatus is designed to measure the absorption coefficients of ionic liquids under different electric fields. Five groups of imidazole ionic liquids are experimentally investigated and an inversion is performed to determine the spectral absorption coefficients of the imidazole ionic liquids under the electric fields. Different intensities with multiple interface refractions and reflections are also considered, and the various measurement errors are analyzed through uncertainties propagation analysis. Spectral absorptions of ionic liquids from 300 nm to 2500 nm are obtained and the absorption coefficients are retrieved. It is found that the absorption behavior of ionic liquids changes in some frequency bands under an applied electric field. The experimental results show that the absorption coefficient of the ionic liquid increases with the voltage increasing at 1520 nm and 1920 nm. The change rate is affected by the types of anions and cations in the ionic liquid and the diffusion rate of the ions therein. This study provides illustrations for the ionic liquid-based electro-optical regulation in terms of physical property parameters and the testing technique.

关键词： ionic liquid absorption coefficient electro-optical property uncertainty propagation analysis

Fe-Mo-B Enhanced Sintering of P/M 316L Stainless Steel

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Journal of Iron and Steel Research International 2008年第1期15卷 10-14页

作者： YANG Xia GUO shi-ju Institute of Powder Metallurgy University of Science and Technology Beijing Beijing 100083 China

Liquid-phase enhanced sintering of powder metallurgy（P/M）316L stainless steel by addition of sintering aids was studied.2%-8% of pre-alloyed Fe-Mo-B powder with two different particle sizes was added as sintering aids,and the specimens were sintered in vacuum at 1 200-1 350 ℃.The results show that the fine Fe-Mo-B powder（5-10 μm）has stronger activated *** sintered density increases with the increase in sintering aid content or sintering *** compaction has a better effect on the control of dimensional precision of *** prealloyed Fe-Mo-B powder deviated from Mo2FeB2 component can also be sintering aid of P/M 316L stainless steel.

关键词： P/M 316L stainless steel liquid-phase sintering activated sintering Fe-Mo-B sintering aid

HUITWU： An Efficient Algorithm for High-Utility Itemset Mining in Transaction Databases

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Journal of Computer Science & Technology 2016年第4期31卷 776-786页

作者： shi-Ming Guo hong Gao School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China

Mining high-utility itemsets （HUIs） from a transaction database refers to the discovery of itemsets with high utilities like profits. Most of existing studies discover HUIs from a transaction database in two phases. In phase 1, different overestimation methods are applied to calculate the upper bounds of the utilities of itemsets. Since the overestimated utilities of itemsets are adopted, the itemsets whose overestimated utilities are no less than a user-specified threshold are selected as candidate HUIs, and they are verified by scanning the database one more time in phase 2. However, a large number of candidate HUIs incur two problems： 1） it requires excessive memory to store these candidates; 2） it needs a large amount of running time to calculate their exact utilities. Vertical data format has been applied to mine HUIs recently. However this kind of method cannot deal with transactions with the same items effectively so that the size of database cannot be reduced sufficiently. The overall performance of algorithms is degraded consequently. Thus an algorithm HUITWU is proposed in this paper for mining HUIs. A novel data structure HUITwu-Tree is adopted to efficiently calculate the utilities of itemsets in a database. Extensive studies with both sparse and dense datasets have demonstrated that our proposed algorithm is more than an order of magnitude faster and consumes less memory than the state-of-the-art algorithms.

关键词： data mining high-utility itemset pattern growth