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Applied Mathematics(A Journal of Chinese Universities) 2013年第4期28卷 494-504页

作者： WANG Xiao-guang YIN Yong-cheng Department of Mathematics Zhejiang University

We give a survey of many diff erent topological structure arise in the dynamical and parameter planes of McMullen maps.

关键词： Fatou set and Julia set McMullen map hyperbolic component Jordan curve

Culturing the Segments of Bryopsis hypnoides Lamouroux Thalli Regenerated from Protoplast Aggregations

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Journal of Integrative Plant Biology 2006年第2期48卷 190-196页

作者： guang-Ce Wang cheng-Kui Tseng Institute of Oceanology the Chinese Academy of Sciences Qingdao 266071 China

Bryopsis hypnoides Lamouroux was regenerated In vitro from the protoplasm squeezed out from wild algae and the regenerated Individuals had an advantage over Indlvlduala from the wild In terms of growth. Culturing of segments of thalll also showed that segments from the regenerated algae grew better than those from individuals from the wild. The segment that corresponds to a part of a cell, at least a part of the protoplasm, can develop Into a mature Individual, Including rhlzold and thallus, suggesting that a multlnucleate alga, such as B. hypnoides, Is different from higher plants, whose totlpotancy Is based on an Intact cell （or protoplasm）. Further cultivation of mature Individuals from segments Indicated that the organelles In the thallus had two ways In which they could survive when the alga was on the decline：（Ⅰ） the organelles were transferred Into a ball with a gelatinous envelope through a formed pipe and the ball seemed to be capable of being propagated; and （Ⅱ） the organelles were aggregated In the thallus and then moved to the outside. An Interesting result Is that one organelle aggregation located outside the thallus germinated and developed Into a mature alga, although most organelle aggregations gradually lost vitality and died. The results of the present study reveal that the aggregation of organelles can regenerate a stronger organism than Individuals from the wild owing to the complete exchange of genetic material and may possibly enable organelles to survive in unfavorable surroundings.

关键词： aggregation Bryopsis hypnoides culturing thallus segment development germination protoplast.

Monthly discharge forecasting using wavelet neural networks with extreme learning machine

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Science China(Technological Sciences) 2014年第12期57卷 2441-2452页

作者： LI bao Jian cheng Chun Tian Institute of Hydropower System and Hydroinformatics Dalian University of Technology

Accurate and reliable hydrological forecasting is essential for water resource management. Feedforward neural networks can provide satisfactory forecast results in most cases, but traditional gradient-based training algorithms are usually time-consum- ing and may easily converge to local minimum. Hence, how to obtain more appropriate parameters for feedforward neural networks with more precise prediction within shorter time has been a challenging task. Extreme learning machine （ELM）, a new training algorithm for single-hidden layer feedforward neural networks （SLFNs）, has been proposed to avoid these disad- vantages. In this study, a conjunction model of wavelet neural networks with ELM （WNN-ELM） is proposed for 1-month ahead discharge forecasting, The ~ trous wavelet transform is used to decompose the original discharge time series into several sub-series. The sub-series are then used as inputs for SLFNs coupled with ELM algorithm （SLFNs^ELM）; the output is the next step observed discharge. For comparison, the SLFNs-ELM and support vector machine （SVM） are also employed. Monthly discharge time series data from two reservoirs in southwestern China are derive] for validating the models. In addi- tion, four quantitative standard statistical performance evaluation measures are utilized to evaluate the model performance. The results indicate that the SLFNs-ELM performs slightly better than the SVM for peak discharge estimation, and the proposed model WNN-ELM provides more accurate forecast precision than SLFNs-ELM and SVM

关键词： monthly discharges discrete wavelet transform extreme learning machine forecasting

Profiling of differentially expressed chemotactic-related genes in MCP-1 treated macrophage cell line using human cDNA arrays

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World Journal of Gastroenterology 2005年第16期11卷 2508-2512页

作者： guang-XingBian HongMiao LeiQiu Dong-MeiCao bao-YuGuo DepartmentofBiochemicalPharmacy SchoolofPharmacySecondMilitaryMedicalUniversityShanghai200433China DepartmentofPathologyandPhysiology CollegeofBasicMedicalSciencesSecondMilitaryMedicalUniversityShanghai200433China

AIM: To study the global gene expression of chemotactic genes in macrophage line U937 treated with human monocyte chemoattractant protein-1 (MCP-1) through the use of ExpreeChipTMO2 cDNA array. METHODS: Total RNA was extracted from MCP-1 treated macrophage line U937 and normal U937 cells, reversely transcribed to cDNA, and then screened in parallel with HO2 human cDNA array chip. The scanned result was additionally validated using RT-PCR. RESULTS: The result of cDNA array showed that one chemotactic-related gene was up-regulated more than two-fold (RANTES) and seven chemotactic-related genes were down-regulated more than two-fold (CCR1, CCR5, ccll6, GROβ, GROγ,IL-8 and granulocyte chemotactic protein 2) in MCP-1 treated U937 cells at mRNA level. RT-PCR analysis of four of these differentially expressed genes gave results consistent with cDNA array findings. CONCLUSION: MCP-1 could influence some chemokine and receptor expressions in macrophages in vitro. MCP-1 mainly down-regulates the expression of chemotactic genes influencing neutrophilic granulocyte expression (GROβ, GROγ, IL-8 and granulocyte chemotactic protein 2), and the mRNA level of CCR5, which plays a critical role in many disorders and illnesses.

关键词： MCP-1 ExpreeChip^(TM)HO_2

Mechanism and application of an online intelligent evaluation model for energy consumption of a reheating furnace

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Journal of Iron and Steel Research International 2023年第1期30卷 102-111页

作者： Xiang-jun bao Jing Xu guang Chen Xu Chen Hong-guang Zhang Yi-ming Shen Wei Zhai Department of Thermal Energy School of Energy and EnvironmentAnhui University of TechnologyMa’anshan 243002AnhuiChina Department of Metallurgical Engineering School of Energy and EnvironmentAnhui University of TechnologyMa’anshan 243002AuhuiChina Department of Construction and Environmental Engineering School of Architectural EngineeringAnhui University of TechnologyMa’anshan 243002AnhuiChina Ma’anshan Iron and Steel Co. Ltd.Ma’anshan 243003AnhuiChina

An online model was proposed to identify the reasons behind changes in the energy consumption of the reheating furnace of a steel processing *** heat conversion of the furnace was analyzed and integrated with the fuel consumption of the furnace to obtain a model of the energy *** with the mechanism analysis,the basic parameters affecting energy consumption were determined,and four key influencing factors were obtained:furnace output,furnace charging temperature,furnace tapping temperature,and steel *** specific calculation method of the contribution of each influencing factor was derived to define the conditions of the baseline energy consumption,while the online data were used to calculate the energy value and the actual performance value of the baseline energy *** contribution of each influencing factor was determined through *** cloud platform was used for database reconstruction and programming to realize the online intelligent evaluation of the energy consumption of the reheating ***,a case study of the evaluation of the practical energy consumption of a steel rolling furnace in a steel plant was *** intelligent evaluation results were quantified and displayed online,and the performance of the system in reducing production line energy consumption was demonstrated.

关键词： Online intelligent evaluation Model mechanism Contribution Data reconstruction

Precipitation behavior of titanium nitride on a primary inclusion particle during solidification of bearing steel

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Journal of Iron and Steel Research International 2017年第7期24卷 685-690页

作者： Liang Yang Bryan A. Webler Guo-guang cheng State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Center for Iron and Steelmaking Research Department of Materials Science and EngineeringCarnegie Mellon University

Titanium nitride precipitation on a primary inclusion particle during solidification of bearing steel has been tracked by varying temperature in a confocal scanning violet laser *** precipitation,an obvious growth of titanium nitride on a primary inclusion particle was observed due to the rapid solute diffusion in liquid *** onset of titanium nitride precipitation did not change with primary inclusion particle size,but the time of growth was greater for a smaller primary inclusion ***,the particle size displayed little influence on the total precipitated amount of titanium nitride on it under the same *** the later period of solidification,almost no change occurred in inclusion size,but the inclusion shape varied from circle to almost square in two-dimension,or cubic in three-dimension,to attain the equilibrium with steel.

关键词： Real time observation Titanium nitride growth Bearing steel Precipitation Solidification Inclusion

Electrochemical behavior and corrosion resistance of IrO2–ZrO2 binary oxide coatings for promoting oxygen evolution in sulfuric acid solution

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International Journal of Minerals,Metallurgy and Materials 2020年第2期27卷 264-273页

作者： bao Liu Shuo Wang cheng-yan Wang bao-zhong Ma Yong-qiang Chen School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Rare and Precious Metals Green Recycling and Extraction University of Science and Technology BeijingBeijing 100083China

In this study,we prepared Ti/IrO2–ZrO2 electrodes with different ZrO2 contents using zirconium-n-butoxide(C16H36O4Zr)and chloroiridic acid(H2IrCl6)via a sol–gel *** explore the effect of ZrO2 content on the surface properties and electrochemical behavior of electrodes,we performed physical characterizations and electrochemical *** obtained results revealed that the binary oxide coating was composed of rutile IrO2,amorphous ZrO2,and an IrO2–ZrO2 solid *** IrO2–ZrO2 binary oxide coatings exhibited cracked structures with flat regions.A slight incorporation of ZrO2 promoted the crystallization of the active component ***,the crystallization of IrO2 was hindered when the added ZrO2 content was greater than 30at%.The appropriate incorporation of ZrO2 enhanced the electrocatalytic performance of the pure IrO2 *** Ti/70at%IrO2–30at%ZrO2 electrode,with its large active surface area,improved electrocatalytic activity,long service lifetime,and especially,lower cost,is the most effective for promoting oxygen evolution in sulfuric acid solution.

关键词： electrode IrO2-ZrO2 oxygen evolution reaction electrochemical behavior corrosion resistance

2T-PERIODIC SOLUTION FOR m ORDER NEUTRAL TYPEDIFFERENTIAL EQUATIONS WITH TIME DELAYS

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Applied Mathematics and Mechanics(English Edition) 2002年第1期23卷 100-106页

作者： ZHANG bao-sheng(张保生) ZHU guang-hui(朱光辉) Department of Mathematics Yunnan Nationalities InstituteKunming 650031 P R China Department of Mathematics Yunnan Nationalities InstituteKunming 650031 P R China

Periodic solution of m order linear neutral equations with constant coefficient and time delays was studied. Existence and uniqueness of 2 T-periodic solutions for the equation were discussed by using the method of Fourier series. Some new necessary and sufficient conditions of existence and uniqueness of 2 T-periodic solutions for the equation are obtained. The main result is used widely. It contains results in some correlation paper for its special case, improves and extends the main results in them. Existence of periodic solution for the equation in larger number of particular case can be checked by using the result, but cannot be checked in another paper. In other words, the main result in this paper is most generalized for (1) the better result cannot be found by using the same method.

关键词： neutral type equation 2T-periodic solution Fourier series

Feasibility evaluation of failure models for predicting forming limit of metal foils

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Chinese Journal of Aeronautics 2020年第9期33卷 2461-2471页

作者： bao MENG Jiejie SHI Yiyun ZHANG cheng cheng Bolin MA Min WAN School of Mechanical Engineering and Automation Beihang UniversityBeijing 100083China

Forming limit of metal foil is an important index to evaluate its formability,and is of considerable significance to improve the quality of *** ductile fracture(DF)behavior in microscale plastic deformation is remarkably affected by the geometry and grain *** explore the size-dependent forming limit curve(FLC),the Holmberg and Marciniak tests of SUS304 foils with the thicknesses of less than 0.1 mm and diverse grain sizes were *** addition,the validity and feasibility of three types of existing failure models including Swift/Hill,MarciniakKuczynski(M-K)and DF criteria for predicting the micro-scaled FLCs were *** is found that the Swift/Hill model possesses the worst accuracy with predicting deviation above 50%.Four classical DF criteria including Freudenthal,Ayada,Brozzo and Oh show great difference,and Oh model considering plastic anisotropy presents the best *** predicted deviation of M-K model is aggravated with increasing grain size and decreasing foil thickness,which is attributed to the intensified free surface roughening and transformation of fracture mechanism with *** research thus provides a deeper understanding and valuable reference for the widespread application of FLC in microforming.

关键词： Failure criteria Forming limit Metal foil Microforming Size effect

Tadpole types of Chinese megophryid frogs （Anura： Mego- phryidae） and implications for larval evolution

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Current Zoology 2011年第1期57卷 93-100页

作者： cheng LI Xian-guang GUO Yue-Zhao WANG chengdu Institute of Biology Chinese Academy of Sciences Chengdu Sichuan 610041 China Graduate University of the Chinese Academy of Sciences Beijing 100039 China

The larval body shapes and oral discs of 30 frog species from the family Megophryidae from China were examined. Using a phylogenetic framework derived from a Bayesian analysis of published mitochondrial cytochrome b and 16S rRNA gene sequences, we deduced a pattern of historical change among megophryid larval forms. These larvae were categorized into four types according to their body shapes and oral discs：（A） Leptobrachiini type, （B） Lalax type, （C） Brachytarsophrys type, and （D） Megophryini type, of which B and C are novel types. Type A is characterized by a typical oral disc with multiple rows of teeth, representing the tadpole type of the most recent common ancestor of the family Megophryidae. Type B has a typical oral disc with reduced tooth rows, an elongated labium, and integumentary glands. Type C has no labial teeth and a smaller umbelliform oral disc. Type D is characterized by a lack of labial teeth, an enlarged umbelliform oral disc, representing the tadpole of the most recent common ancestor of the subfamily Megophryinae. Our analysis supports the hypothesis that the umbelliform oral disc is apomorphic and also reveals the close association between morphology and microhabitat

关键词： Megophryidae Tadpoles Lalax type Brachytarsophrys type Novel tadpole types