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The restricted EM algorithm under linear inequalities in a linear model with missing data

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Science china Mathematics 2005年第6期48卷 819-828页

作者： ZHENG Shurong, SHI Ningzhong & GUO Jianhua School of Mathematics and Statistics, Northeast Normal University, changchun 130024, china Institute of Mathematics, jilin University, changchun 130012, china 1. School of Mathematics and Statistics Northeast Normal University 130024 Changchun China 2. Institute of Mathematics Jilin University 130012 Changchun China

This paper discusses the maximum likelihood estimate of β under linear inequalities A0β≥ a in a linear model with missing data, proposes the restricted EM algo rithm and proves the convergence.

关键词： EM algorithm, linear model, maximum likelihood estimate, missing data.

A STUDY ON DESERTIFICATION OF WEST jilin PROVINCE BASED ON REMOTE SENSING AND GIS TECHNIQUES

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Chinese Geographical Science 2002年第1期12卷 73-79页

作者： ZHU Jin hua, LI Jin song(changchun Institute of Geography, the Chinese Academy of Sciences, changchun 130021, P.R. china) changchun Institute of Geography the Chinese Academy of Sciences Changchun P. R. China

'West jilin Province' in this paper means Zhenlai, Baicheng, Taonan, Da'an,Tongyu, Fuyu, Songyuan, Qian'an, Changling, also includes Gongzhuling, Shuangliao, Lishu, Siping andNong' an which have been suffered from desertification. In west jilin Province there are three sandzones passing through, they are Xiang (Xianghai) -Wu (Ulan Tug) sand zone, Hai-Feng sand zone, andTao'er River right bank sand zone. The desertification area of west jilin Province is 819 100 ha,making up 12. 5% of the total land area. Among desertification types, in jilin Province lightdesertification is the major, then is medium decertification, hevey desertification is the *** to the comparison of the interpretation results of the Landsat images of the 1980s and the1990s by remote sensing and GIS techniques, it can be seen that the desertification area in westjilin Province basically didn't change on the whole, only increased 6130 ha, making up 0. 8% of thedesertification area, change scale is less than 1%. Evidently, desertification is controlled mostly,but some areas are continuing deterioration. The desertification process of china can be dividedinto three types according to origin nature, they are sandy steppe desertification, fixed sandarea(sand land) activation and dunes transfer invasion. Reasons of desertification of West jilinProvince are analyzed, they include natural factors (such as material source factors, chimatefactors) and artificial factors (such as destroying grass to reclaim, steppe decreasing greatly,illegally feeling shelter forest stands, constructing reservoir to influence eco-environment etc. ).Some suggestions are put forward as follows: establishing the social project for ecologicalreconstruction of degenerated land; intensifying planning and management of land use, revertingfarmland into forestland or pasture in a planned way. The key desertification control is to dependmainly on policy and management, then control techniques.

关键词： remote sensing (RS) and GIS techniques desertification west jilin province

Continuous Solutions of the First Boundary Value Problems for Nonlinear Diffusion Equations

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Acta Mathematica Sinica,English Series 1994年第1期10卷 64-71页

作者： Yin Jingxue Department of Mathematics jilin University changchun,130023 china 1. Department of Mathematics Jilin University 130023 Changchun China

We establish the existence of continuous solutions of the first boundary value prob- lem for nonlinar diffusion equations of the form θu/ t=div(α（u）|▽u|m-1▽u)+ （u）▽u, under the conditions that A（s）=integral from n=o to s(a1/m（σ）dσis strictly increasing and m>n-1,where n is the space ***,the uniqueness is proved for solutions with some regularities.

关键词： Math lim

Effect of Nb on the Interfacial Wettability in Al_2O_3/Medium Mn Steel

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Journal of Materials Science & Technology 2003年第6期19卷 625-627页

作者： Sirong YU, Yaohui LIU and Zhenming HECollege of Materials Science and Engineering, jilin University, changchun 130025, china College of Materials Science and Engineering Jilin University Changchun 130025 China

To develop medium Mn steel (MMS) matrix composites reinforced by AI2O3 particles, the effect of Nb on the interfacial wettability of AI2O3/MMS and its mechanism were investigated in this paper. The results show that the wetting angle of the specimens with different Nb contents are bigger than that of the specimen without Nb at the first stage, and then decreases with time at 1450℃. At certain time, the wetting angle is lower than that of the specimen without Nb. At 1550 and 1600℃, the wetting angle of the specimens containing Nb decreases quickly with time at first stage. After 10 min, the wetting angle reaches a steady state, and hardly changes with time. The mechanisms of Nb to improve the wettability can be attributed to the enrichment of Nb at the interface and Nb serves as surface active agent of MMS at T3/MMS at T>1550℃, and reduces the interfacial energies.

关键词： Madium Mn steel A12O3 Nb Wettalility

A Study of LD Modulation Property by Pulse Prebias Technique

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Chinese Journal of Lasers 1997年第5期B6卷 429-434页

作者： JIN Enshun SHI Jiawei ZHANG Yujun(Dept. of Electronics Engineering, jilin University, changchun 130023, china State KeyLaboratory on Integrated Optoelectronics, jilin University Region, changchun 130023, china) jilin Univ Changchun China

The pulse prebias technique is firstly applied to study on the modulation properties of the LD, high speed LED, and integrated laser transmitter. The results obtained from this technique agree well with those from DC... 详细信息

关键词： modulate modulation bandwidth

Geochemistry and Genesis of the Sodium-Charnockitic Gneisses, Eastern Hebei Province, china

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Acta Geologica Sinica(English Edition) 1992年第3期66卷 239-258页

作者： Wang Anjian changchun University of Earth Sciences, changchun, jilin changchun University of Earth Sciences Changchun Jilin

High in sodium and low in potassium (Na_2O/ K_2O>1), the charnockitic gneiss series in theSantunying- Taipingzhai area, eastern Hebei province, consists of hypersthene- quartz- diorite,hypersthene-granodiorite and hypersthene-plagioclase-granite. Geological, petrological and large ion lithophileelement(LILE), high field strength element (HFSE) and REE geochemical studies suggest that themedium-coarse-grained hypersthene-granodiorite is the product of crystallization of anatectic magmas of thesame composition. Under granulite facies conditions, the equilibrium crystallization differentiation of themagmas yielded the early crystallization phase-high-SiO_2, LILE-depleted, low-∑REE, positive Eu anomalyand REE- saturated hypersthene- plagioclase- granite. The residual phase, coarse- grained to pegmatitichypersthene- granodiorite, is marked by low SiO_2, LILE-enrichment, high ∑REE and *** rocks and hypersthene-quartz-diorite enclaves constitute the sodium-charnockitic gneiss series in easternHebei province. Model calculation for trace elements in the granitoids was applied. On the basis of a systematicgeological study, the equation for calculation was chosen, the source magma was determined and the partitioncoefficients were obtained. The resulting curves are entirely consistent with those observed in the patterns of ac-tual rocks. The study indicates that whole-rock REE patterns can not be used directly in the comparison of thesources and genesis of granitoids.

关键词： sodium-charnockitic gneisses geochemistry genesis eastern Hebei province

Study on the stability and 3-dimensional character for natural convection in a rectangular cavity heated from below

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Science china(Technological Sciences) 2010年第6期53卷 1647-1654页

作者： ZHAN NaiYan1,2,XU PeiWei1,SUN ShiMei,YANG Mo2 & LIU Jun3 1 Scool of Municipal and Environmental Engineering,jilin Institute of Architectural and Civil Engineering,changchun 130021,china 2 College of Power Engineering,University of Shanghai for Science and Technology,Shanghiai 200093,china 3 College of Power Engineering,jilin University,changchun 130000,china 1. Scool of Municipal and Environmental Engineering Jilin Institute of Architectural and Civil Engineering Changchun 130021 China2. College of Power Engineering University of Shanghai for Science and Technology Shanghiai 200093 China3. College of Power Engineering Jilin University Changchun 130000 China

Natural convection of air is numerically simulated in a 3-dimensional rectangular cavity heated from below using SIMPLE algorithm with a QUICK *** results suggest that when all lateral walls are adiabatic,the fluid rolls occur along the long *** the Rayleigh number is smaller,the flow is of 2-dimensional character,and the rolls shapes are *** average Nusselt numbers in the central part of the cavity are *** average Nusselt numbers in the part near by the cavity are *** to the comparison of 3-dimensional results with 2-dimensional results,the flow patterns and heat transfer in the central part of the cavity can be assumed as a 2-dimensional flow,While those in the part near by the cavity can *** increasing Rayleigh number,the flow is 3-dimensional *** 3-dimensional result accords with the experimental *** all lateral walls are adiabatic,the ten rolls occur along the long *** when lateral walls are heated or cooled,the rolls disappear along the long axis and two rolls occur along the short *** rotation direction of the rolls is *** Rayleigh number is over some critical value,flow and heat transfer will be asymmetry,indicating unsteady oscillation *** nonlinear analyses,it is shown that with increasing Rayleigh number,flow and heat transfer will change from steady state to unsteady state through HOPF bifurcation,and transition to chaos will occur through multi-periodical oscillation.

关键词： Critical Raleigh number 3-dimensional character lateral boundaries nonlinear characteristic bifurcation

Effect of solution concentration on the structured order and optical properties of short-chain polyene biomolecules

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1646-1650页

作者： OUYANG ShunLi1,2,SUN ChengLin1,2,ZHOU Mi1,2,LI DongFei2,WANG WeiWei1,2,QU GuanNan1,LI ZuoWei1,2,GAO ShuQin1 & YANG JianGe3 1 State Key Laboratory of Superhard Materials,jilin University,changchun 130012,china 2 College of Physics,jilin University,changchun 130023,china 3 The ordnance Engineering Department,Air Force Aviation University,changchun 130022,china 1. State Key Laboratory of Superhard Materials Jilin University Changchun 130012 China2. College of Physics Jilin University Changchun 130023 China3. The ordnance Engineering Department Air Force Aviation University Changchun 130022 China

We have measured the Raman spectra and UV-Vis absorption spectra of linear polyene biomolecules(β-carotene and lycopene) in CS2 at low concentrations(10-6-10-10 mol/L).With decreasing concentration,all the carbon-carbon vibrations form a coherent mode in ordered β-carotene and lycopene due to extended π-conjugation that gives strong electron-phonon coupling,which leads to an anomalous experimental *** observed an extremely high Raman scattering cross section(RSCS) and the Raman activities in β-carotene and lycopene are characterized by intensive overtones and ***,the UV-Vis absorption bands become narrower.

关键词： molecular structured order Raman spectroscopy Raman scattering cross section

Identification and Validation of Vascular-Associated Biomarkers for the Prognosis and Potential Pathogenesis of Hypertension Using Comprehensive Bioinformatics Methods

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World Journal of Cardiovascular Diseases 2024年第3期14卷 115-128页

作者： Xiangguang Chang Lei Guo Liying Zou Yazhao Ma jilin Feng Department of Laboratory Yangbi Yi Autonomous County People’s Hospital Dali China Department of Obstetrics and Gynecology Yangbi Yi Autonomous County People’s Hospital Dali China Department of Infectious Diseases Yangbi Yi Autonomous County People’s Hospital Dali China Medical Community Office Yangbi Yi Autonomous County People’s Hospital Dali China

Background: Hypertension, also known as increased blood pressure, is a phenomenon in which blood flows in blood vessels and causes persistently higher-than-normal pressure on the vessel wall. The identification of novel prognostic and pathogenesis biomarkers plays a key role in the management of hypertension. Methods: The GSE7483 and GSE75815 datasets from the gene expression omnibus (GEO) database were used to identify the genes associated with hypertension that were differentially expressed genes (DEGs). The functional role of the DEGs was elucidated by gene body (GO) enrichment analysis. In addition, we performed an immune infiltration assay and GSEA on the DEGs of hypertensive patients and verified the expression of novel DEGs in the blood of hypertensive patients by RT-qPCR. Results: A total of 267 DEGs were identified from the GEO database. GO analysis revealed that these genes were associated mainly with biological processes such as fibroblast proliferation, cell structural organization, extracellular matrix organization, vasculature development regulation, and angiogenesis. We identified five possible biomarkers, Ecm1, Sparc, Sphk1, Thbsl, and Mecp2, which correlate with vascular development and angiogenesis characteristic of hypertension by bioinformatics, and explored the clinical expression levels of these genes by RT-qPCR, and found that Sparc, Sphk1, and Thbs1 showed significant up-regulation, in agreement with the results of the bioinformatics analysis. Conclusion: Our study suggested that Sparc, Sphk1 and Thbs1 may be potential novel biomarkers for the diagnosis, treatment and prognosis of hypertension and that they are involved in the regulation of vascular development and angiogenesis in hypertension.

关键词： Hypertension Biomarkers Differentially Expressed Genes Vascular Development and Angiogenesis Bioinformatics Analysis