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Hausdorff Measures for a Class of Homogeneous Cantor Sets

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Acta Mathematicae Applicatae Sinica 2013年第1期29卷 117-122页

作者： cheng-qin qu Department of Applied Mathematics South China University of Technology

We consider the homogeneous Cantor sets which are generalization of symmetric perfect sets, and give a formula of the exact Hausdorff measures for a class of such sets.

关键词： Hausdorff measure Homogeneous Cantor set convexity

Decomposition characteristics of organic materials and their effects on labile and recalcitrant organic carbon fractions in a semi-arid soil under plastic mulch and drip irrigation

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Journal of Arid Land 2018年第1期10卷 115-128页

作者： hu juan wu jinggui qu xiaojing college of resource and environmental science jilin agricultural universityChangchun 130118China

Labile organic carbon （LC） and recalcitrant organic carbon （RC） are two major fractions of soil organic carbon （SOC） and play a critical role in organic carbon turnover and sequestration. The aims of this study were to evaluate the variations of LC and RC in a semi-arid soil （Inner Mongolia, China） under plastic mulch and drip irrigation after the application of organic materials （OMs）, and to explore the effects of OMs from various sources on LC and RC by probing the decomposition characteristics of OMs using in-situ nylon mesh bags burying method. The field experiment included seven treatments, i.e., chicken manure （CM）, sheep manure （SM）, mushroom residue （MR）, maize straw （MS）, fodder grass （FG）, tree leaves （TL） and no OMs as a control （CK）. Soil LC and RC were separated by Huygens D＇s method （particle size-density）, and the average soil mass recovery rate and carbon recovery rate were above 95%, which indicated this method was suitable for carbon pools size analysis. The LC and RC contents significantly （P〈0.01） increased after the application of OMs. Moreover, LC and RC contents were 3.2%-8.6% and 5.0%-9.4% higher in 2016 than in 2015. The applications of CM and SM significantly increased （P〈0,01） LC content and LC/SOC ratio, whereas they were the lowest after the application of TL. However, SOC and RC contents were significantly higher （P〈0.01） after the applications of TL and MS. The correlation analysis indicated the decomposition rate of OMs was positively related with LC content and LC/SOC ratio. In addition, lignin, polyphenol, WOM （total water-soluble organic matter）, WHA （water-soluble humic acid）, HSL （humicdike substance） and HAL （humic acid-like） contents in initial OMs played important roles in SOC and RC. In-situ nylon mesh bags burying experiment indicated the decomposition rates of CM, SM and MS were significantly higher than those of MR, FG, and TL. Furthermore, MS could result in more lignin derivatives, WHA, and HAL polymers in shorter time

关键词： organic materials labile organic carbon recalcitrant organic carbon decomposition characteristics plasticmulch drip irrigation Inner Mongolia

Adaptive Multi-phenotype Based Gene Expression Programming Algorithm

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Chinese Journal of Electronics 2016年第5期25卷 807-816页

作者： LI qu cheng Hongbing YAO Min School of Computer Science and Technology Zhejiang University of Technology College of Computer Science Zhejiang University State Key Laboratory for Novel Software Technology Nanjing University

Expression theory is the mathematical foundation of evolutionary computation. In order to investigate the problems in Gene expression programming(GEP) expression theory, we clarified the difference between genotypic expression space and phenotypic expression space. We also presented phenotypic expression space definition and theory. Then we analyzed the reason of good and bad performance of different GEP algorithms based on expression space theory. We also proposed a new Adaptive multi-phenotype gene expression programming(AMGEP),in which the potential of genes is fully activated with gene combination. Experiments on benchmark problems showed that genotypic expression space and phenotypic expression space theory can explain the different performance of different algorithms and showed that AMGEP outperform other GEP algorithms in terms of search ability.

关键词： Gene expression programming(GEP) Genotype Phenotype Population diversity

Real-time full-color meta fiber endoscopy

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Light(Science & Applications) 2023年第8期12卷 1452-1453页

作者： Changyuan Yu Zhi cheng Jiaqi qu Photonics Research Institute Department of Electrical and Electronic EngineeringThe Hong Kong Polytechnic UniversityHong KongChina

The remarkable capacity of metasurfaces to exert precise control over the propagation of light has ushered in a realm of unprecedented possibilities for"Lab-on-fiber",and in this work,showcased real-time full-color im... 详细信息

关键词： fiber full precise

Optimization of the transmission mechanism for wireless TCP

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 38-42页

作者： qu Zhao-wei ZHANG juan Beijing University of Posts and Telecommunications Beijing 100876 China

A novel method which can detect the possible handoffs for mobile nodes is proposed in this article. The method can be deployed on mobile nodes. So when a possible handoff occurs, mobile nodes can detect and take some necessary actions in time. In this study, the method is also used to optimize the transmission mechanism of Q-TCP. Moreover, the simulation results show that Q-TCP can provide better quality of service （QoS） for mobile nodes when they are moving among different agents.

关键词： wireless TCP data stream handoff QoS

X-ray Spectroscopy of Dips of Cir X-1

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Chinese Journal of Astronomy and Astrophysics 2007年第5期7卷 693-704页

作者： Ya-juan Lei Fang-Jun Lu Jin-Lu qu Li-Ming Song cheng-Min Zhang Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

We present X-ray spectral analyses of the low-mass X-ray binary Cir X-1 during X-ray dips, using the Rossi X-ray Timing Explorer （RXTE） data. Each dip was divided into several segments, and the spectrum of each segment was fitted with a three-component blackbody model, in which the first two components are affected by partial covering and the third one is unaffected. A Gaussian emission line is also included in the spectral model to represent the Fe Kα line at - 6.4 keV. The fitted temperatures of the two partially covered components are about 2 keV and 1 keV, while the uncovered component has a temperature of -0.5-0.6 keV. The equivalent blackbody emission radius of the hottest component is the smallest and that of the coolest component is the largest. During the dips the fluxes of the two hot components are linearly correlated, while that of the third component does not show any significant variation. The Fe line flux remains constant, within the errors, during the short dips. However, during the long dips the line flux varies significantly and is positively correlated with the fluxes of the two hot components. These results suggest; （1） that the temperature of the X-ray emitting region decreases with radius, （2） that the Fe Kα line emitting region is close to the hot continuum emitting region, and （3） that the size of the Fe line emitting region is larger than that of the obscuring matter causing the short dips but smaller than the region of that causing the long dips.

关键词： stars individual (Circinus X-1) -- stars neutron -- X-rays stars

A Novel Sparse Penalty for Singular Value Decomposition

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Chinese Journal of Electronics 2017年第2期26卷 306-312页

作者： WANG Caihua LIU juan MIN Wenwen qu Aiping The State Key Laboratory of Software Engineering School of ComputerWuhan University

Singular value decomposition(SVD) is a tool widely used in data denoising,matrix approximation,recommendation system,text mining and computer vision.A ma jority of applications prefer sparse singular vectors to capture inherent structures and patterns of the input data so that the results are *** present a novel penalty for SVD to achieve *** with the traditional penalties,the proposed penalty is scale,dimensional insensitive and bounded between 0 and 1,which are in favor of controlling *** by the penalty,we provide an efficient algorithm to pro ject a vector onto a given sparse level in O(n) expected *** efficient pro jection algorithm serve as a drudge for sparse SVD(SSVD).In experiments,SSVD is efficient and could capture the latent structures and patterns of the input data.

关键词： Sparse controllable projection(SCP) Sparse singular value decomposition(SSVD) Sparse low rank matrix approximation(SLRMA)

Promising thermal photonic management materials for sustainable human habitat

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Nano Research 2024年第1期17卷 112-131页

作者： Houze Yao Qihua Liao Huhu cheng Liangti qu Key Laboratory of Organic Optoelectronics&Molecular Engineering Ministry of EducationDepartment of ChemistryLaboratory of Flexible Electronics TechnologyTsinghua UniversityBeijing 100084China State Key Laboratory of Tribology in Advanced Equipment(SKLT) Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China

The spectral characteristics of outdoor structures,such as automobiles,buildings,and clothing,determine their energy interaction with the environment,from broad-spectrum absorption of light energy to high-efficiency thermal *** developed spectrally selective absorption(SSA)materials permit the reduction of energy loss from human habitat eco-system in the sustainable way and further reduce the utilization of fossil energy to achieve carbon *** we review recent advances in SSA materials that enable rational and efficient management of thermal energy and provide new solutions for the resource base that supports human life like comfortable heat management,electricity production,and water *** basic principles of thermal photonic management,the regulation of SSA materials,and functional properties are *** outlook discussing challenges and opportunities in SSA material energy management for comfortable living environments is finally presented,which expects the enormous potential of this interdisciplinary research in solving growing resource-shortage of human society.

关键词： spectrally selective absorption passive cooling solar power eco-system

Carbon-based functional materials for atmospheric water utilization

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Nano Research 2023年第11期16卷 12491-12505页

作者： Wenya He Tengyu Lin Huhu cheng Liangti qu Laboratory of Flexible Electronics Technology Key Laboratory of Organic Optoelectronics&Molecular EngineeringMinistry of EducationDepartment of ChemistryState Key Laboratory of Tribology in Advanced Equipment(SKLT)Tsinghua UniversityBeijing 100084China

Atmospheric water,as one of the most abundant natural resources on Earth,has attracted huge research interest in the field of water harvesting and energy harvesting and conversion owing its environmental friendliness and easy *** developments of new materials have seen advanced technologies that can extract water and energy out of this long-neglected resource,suggesting a promising and sustainable approach to address the water and energy crises over the ***-based functional materials have been considered to be indispensable materials for atmospheric water utilization due to their large surface area,excellent adsorption performance,and higher surface *** this review,first,we analyze the interaction between carbon-based functional materials and atmospheric water ***,technologies developed in recent years for atmospheric water utilization based on carbon-based functional materials are reviewed,mainly focusing on atmospheric water harvesting,moisture-enabled electricity generation,and moisture-responsive ***,the remaining challenges and some tentative suggestions possibly guiding developments are proposed,which may pave a way for a bright future of carbon-based functional material in the utilization of atmospheric water.

关键词： carbon-based functional material atmospheric water atmospheric water harvesting moisture-enabled power generator moisture actuators