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Multilinear singular and fractional integrals on weighted Hardy spaces

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Applied Mathematics(A Journal of Chinese Universities) 2009年第2期24卷 214-220页

作者： ZHANG Pu lan Jia-cheng Dept. of Math. Mudanjiang Teachers College Mudanjiang 157012 China Dept. of Math. Lishui College Lishui 323000 China

In this paper the boundedness properties of multilinear singular and fractional integrals on the weighted Hardy spaces are studied.

关键词： multilinear singular integral multilinear fractional integral Lipschitz function L^r-Dini condition weighted Hardy space

Multipath Suppressing Method Based on Pseudorange Model Using Modified Teaching-Learning Based Optimization Algorithm

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Chinese Journal of Electronics 2022年第5期31卷 821-831页

作者： cheng lan ZHANG Jing NI Zihang YAN Gaowei Taiyuan University of Technology Xi'an Branch of China Telecom Co.Ltd.

Satellites based positioning has been widely applied to many areas in our daily lives and thus become indispensable, which also leads to increasing demand for high-positioning accuracy. In some complex environments(such as dense urban, valley), multipath interference is one of the main error sources deteriorating positioning accuracy, and it is difficult to eliminate via differential techniques due to its uncertainty of occurrence and irrelevance in different instants. To address this problem,we propose a positioning method for global navigation satellite systems(GNSS) by adopting a modified teachinglearning based optimization(TLBO) algorithm after the positioning problem is formulated as an optimization problem. Experiments are conducted by using actual satellite data. The results show that the proposed positioning algorithm outperforms other algorithms, such as particle swarm optimization based positioning algorithm,differential evolution based positioning algorithm, variable projection method, and TLBO algorithm, in terms of accuracy and stability.

关键词： global navigation satellite systems satellite navigation particle swarm optimisation optimization problem Global Positioning System pseudorange model optimisation modified teaching-learning based optimization algorithm high-positioning accuracy positioning method particle swarm optimization position control evolutionary computation actual satellite data satellites based positioning dense urban valley variable projection method main error sources positioning problem positioning algorithm TLBO algorithm

Model and Simulation of Multipath Error in DLL for GPS Receiver

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Chinese Journal of Electronics 2014年第3期23卷 508-515页

作者： cheng lan CHEN Jie XIE Gang Taiyuan University of Technology Education Ministry Key Laboratory of Complex System Intelligent Control and Decision Beijing Institute of Technology

Although different multipath error models of Delay lock loop(DLL) used in GPS receiver are established, they have never been put together for comparison. Furthermore, no universal simulation method is developed to get a fair comparison among these models. A new model with implicate expression is hence proposed for the coherent DLL and the noncoherent Dot-product(DOT) power mode DLL. Meanwhile, a new simulation method based on the anonymous function in Matlab, which is especially suitable for models with implicit expression,is also proposed to compare the new model with the existing ones. The theoretical analysis and simulation results show that the existing models are the special case of the proposed one. The new simulation method can be used for the comparison of different multipath error models and the multipath error analysis of other DLLs for which only the implicit model is available.

关键词： Delay lock loop(DLL) Multipath Multipath error model Positioning system

Weak Type Endpoint Estimates for Multilinear θ-type Calderon-Zygmund Operators

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Acta Mathematicae Applicatae Sinica 2005年第4期21卷 615-622页

作者： Jia-cheng lan Department of Mathematics Lishui University Lishui Zhejiang 323000 China

In this paper, the author discusses the multilinear singular integrals with certain θ-type Calderdn- Zygmund operators and obtain the boundedness from weak H^1 （R^n） to weak L^1 （R^n）.

关键词： Multilinear singular integrals BMO spaces θ-type Calderdn-Zygmund kernel

Study on the expression of Runx3 and TGF-β_1 protein in the colonic tissue from rats with irritable bowel syndrome

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Asian Pacific Journal of Tropical Medicine 2011年第2期4卷 88-91页

作者： Xiaoning Sun cheng lan Department of Gastroenterology Hainan Provincial People's Hospital

Objective:To investigate the expression of Runx3 and TGF-β_1 protein in the colon from rats with irritable bowel syndrome(IBS).Methods:Rat model for IBS was established by intracolonic instillation with acetic acid and restraint stress methods,which was confirmed by determinating the visceral sensitivity of the animals,including abdominal withdrawal reflex (AWR) score and the electronic behavior of the abdomen *** rats were randomly assigned into three groups:IBS,group(restraint stress,n=25);IBS_2 group(both instillation with acetic acid and restraint stress,n=25) and Control group(n=16).The colonic tissue samples were collected for histological study and the expression of Runx3 and TGF-β_1 proteins were detected by ***,the relationship of these two proteins was calculated. Results:Visceral hypersensitivity(AWR and abdominal electrical activity) was significantly enhanced in IBS,and IBS_2 groups than other *** colon tissue in all groups did not show any signs of ***,the expression of Runx3 and TGF-β_1 protein in the colon from all groups show no significant difference(P>0.05),with no remarkable relevancy between each other(P>0.05).Conclusions:The rat model for IBS was successfully established. We did not find any significant changes in the expression of Runx3 and TGF-β_1 protein in the colon tissue from IBS rats,suggesting that the quantitative changes may be not the way by which Runx3 and TGF-β_1 protein play their roles in *** accurate roles of Runx3 and TGF-β_1 proteins in the pathogenesis of IBS remains to be further studied.

关键词： Runx3 protein TGF-β_1 protein Irritable bowel syndrome Rats model Immunohistochemistry

Field Emission Characteristics of Conducting Polymer Films Conditioned by Electric Discharge

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Journal of Materials Science & Technology 2006年第5期22卷 677-680页

作者： Guohong LAI Zhenglin LI lan cheng Junbiao PENG Key Laboratory of Specially Functional Materials and Advanced Manufacturing Technology Institute of Polymer Optoelectronic Materials and Devices South China University of Technology Guangzhou 510640 China

A pure conducting polymer （PANI-CSA） film conditioned by an electric discharge was tentatively utilized as an cathode for emitting electrons under electric fields. The emission of electrons was observed using a phosphor （ZnO：Zn） screen excited by electrons from the conditioned film. The film morphology was investigated using a scanning electron microscope and it was found that undulate whisker-like sites formed on the surface. The emission was presumably due to the undulate whisker-like sites. The field enhancement factor was estimated to be as high as 1150. The electron emitting process of the PANI-CSA film conditioned by electric discharge was also discussed.

关键词： Conducting polymer Field emission Electric discharge

Noble-metal-free catalyst with enhanced hydrogen evolution reaction activity based on granulated Co-doped Ni-Mo phosphide nanorod arrays

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Nano Research 2020年第12期13卷 3321-3329页

作者： Heping Xie cheng lan Bin Chen Fuhuan Wang Tao Liu Institute of New Energy and Low-Carbon Technology Sichuan UniversityChengdu610065China Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyShenzhen UniversityShenzhen518060China School of Chemical Engineering Sichuan UniversityChengdu610065China

The development of noble-metal-free electrocatalysts for water splitting is indispensable for the efficient production of hydrogen ***,a Co-doped Ni-Mo phosphide nanorod arrays fabricated on porous Ni foam was shown to be an efficient binder-free electrocatalyst for water *** catalyst featured exceptional activity,exhibiting an overpotential of 29 mV at a current density of 10 mA·cm−2 for the hydrogen evolution reaction,whereas the corresponding precatalyst exhibited an overpotential of 314 mV at a current density of 50 mA·cm^−2 for the oxygen evolution *** achieved electrocatalytic performance provided access to a simple water splitting system,affording a current density of 10 mA·cm^−2 at 1.47 V in 1 M KOH *** functional theory results indicated that Co doping and phosphorization were responsible for the high electrocatalytic ***,this work paves the way for the development of novel noble-metal-free electrocatalysts for practical H2 production via water splitting.

关键词： noble-metal-free electrocatalyst overall water splitting cobalt doping phosphorization granulated morphology

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language and Semiotic Studies 2018年第1期4卷 102-124页

作者： Rui-lan cheng Shandong University China

In order to explore the gaps between decoders' interpretations and encoders' designing intentions with respect to the same multimodal discourses, thirty linguistic and thirty art graphic participants were chosen as decoders and encoders, *** participants were required to interpret the same research data in terms of the best and the worst major colors, as well as the best and the worst synergetic patterns formed by major *** was found that the complete unanimity in terms of both color and spatial arrangements among the interpretations between participants only reached 43.3%.The unanimity in the interpretations from the perspective of color alone reached 46.7%.Moreover, the interpretations from the perspective of spatial arrangements present high unanimity, with a rate up to 70%.It is concluded that there are both differences and similarities between the interpretations made by encoders and *** possible reasons underlying both differences and similarities are probed in the present study as well.

关键词： encoders decoders similarities differences multimodal discourses

A unified pre-training and adaptation framework for combinatorial optimization on graphs

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Science China Mathematics 2024年第6期67卷 1439-1456页

作者： Ruibin Zeng Minglong Lei Lingfeng Niu lan cheng School of Computer Science and Technology University of Chinese Academy of SciencesBeijing100049China Faculty of Information Technology Beijing University of TechnologyBeijing100124China School of Economics and Management University of Chinese Academy of SciencesBeijing100190China School of Mathematics and Statistics Central South UniversityChangsha410075China

Combinatorial optimization(CO)on graphs is a classic topic that has been extensively studied across many scientific and industrial ***,solving CO problems on graphs through learning methods has attracted great *** deep learning methods,e.g.,graph neural networks(GNNs),have been used to effectively assist the process of solving ***,current frameworks based on GNNs are mainly designed for certain CO problems,thereby failing to consider their transferable and generalizable abilities among different COs on ***,simply using original graphs to model COs only captures the direct correlations among objects,which does not consider the mathematical logicality and properties of *** this paper,we propose a unified pre-training and adaptation framework for COs on graphs with the help of the maximum satisfiability(Max-SAT)*** first use Max-SAT to bridge different COs on graphs since they can be converted to Max-SAT problems represented by standard formulas and clauses with logical *** we further design a pre-training and domain adaptation framework to extract the transferable and generalizable features so that different COs can benefit from *** the pre-training stage,Max-SAT instances are generated to initialize the parameters of the *** the fine-tuning stage,instances from CO and Max-SAT problems are used for adaptation so that the transferable ability can be further *** experiments on several datasets show that features extracted by our framework exhibit superior transferability and Max-SAT can boost the ability to solve COs on graphs.

关键词： combinatorial optimization graph neural networks domain adaptation maximum satisfiability problem