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Method for Processing Graph Degeneracy in Dynamic Geometry Based on Domain Design

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Journal of Computer Science & Technology 2021年第4期36卷 910-921页

作者： Hao Guan Yong-sheng Rao Jing-Zhong Zhang sheng Cao Xiao-Lin qin Institute of Computing Science and Technology Guangzhou UniversityGuangzhou 510006China Chengdu Institute of Computer Applications Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China School of Computer Science and Engineering University of Electronic Science and Technology of China Chengdu 61173China

A dynamic geometry system,as an important application in the field of geometric constraint solving,is widely used in elementary mathematics education;moreover,the dynamic geometry system is also a fundamental environment for automated theorem proving in *** a geometric constraint solving process,a situation involving a critical point is often encountered,and geometric element degeneracy may occur at this ***,the degeneracy situation must be substantively focused on during the learning and exploration ***,many degeneracy situations cannot be completely presented even by the well-known dynamic geometry *** this paper,the mechanisms causing the degeneracy of a geometric element are analyzed,and relevant definitions and formalized descriptions for the problem are provided according to the relevant modern Euclidean geometry *** solve the problem,the data structure is optimized,and a domain model design for the geometric element and the constraint relationships thereof in the dynamic geometry system are formed;furthermore,an update algorithm for the element is proposed based on the novel domain *** addition,instances show that the proposed domain model and the update algorithm can effectively cope with the geometric element degeneracy situations in the geometric constraint solving process,thereby achieving unification of the dynamic geometry drawing and the geometric intuition of the user.

关键词： dynamic geometry critical point degeneracy domain model

Asymptotic Stability of an Eikonal Transformation Based ADI Method for the Paraxial Helmholtz Equation at High Wave Numbers

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Communications in Computational Physics 2012年第9期12卷 1275-1292页

作者： qin sheng Hai-Wei Sun Center for Astrophysics Space Physics and Engineering ResearchDepartment of MathematicsBaylor UniversityWacoTX 76798-7328USA Department of Mathematics University of MacaoMacao

This paper concerns the numerical stability of an eikonal transformation based splitting method which is highly effective and efficient for the numerical solution of paraxial Helmholtz equation with a large wave *** matrix analysis is conducted in investigations and the oscillation-free computational procedure is proven to be stable in an asymptotic *** examples are given to illustrate the conclusion.

关键词： Paraxial equation highly oscillatory problems eikonal splitting asymptotic stability matrix eigenvalues spectral radius

Explorations and Expectations of Equidistribution Adaptations for Nonlinear Quenching Problems

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Advances in Applied Mathematics and Mechanics 2013年第4期5卷 407-422页

作者： Matthew A.Beauregard qin sheng Department of Mathematics Baylor UniversityTX 76798-7328USA

Finite difference computations that involve spatial adaptation commonly employ an equidistribution *** these cases,a new mesh is constructed such that a given monitor function is equidistributed in some *** choices of the monitor function involve the solution or one of its many *** straightforward concept has proven to be extremely effective and ***,selections of core monitoring functions are often challenging and crucial to the computational *** paper concerns six different designs of the monitoring function that targets a highly nonlinear partial differential equation that exhibits both quenching-type and degeneracy *** the first four monitoring strategies are within the so-called primitive regime,the rest belong to a later category of the modified type,which requires the priori knowledge of certain important quenching solution *** examples are given to illustrate our study and conclusions.

关键词： Degeneracy quenching singularity adaptive differencemethod arc-length monitoring function splitting method

Genetic dissection of drought resistance for trait improvement in crops

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The Crop Journal 2023年第4期11卷 975-985页

作者： shengxue Liu Hongwei Wang feng qin College of Biological Sciences China Agricultural UniversityBeijing 100193China Agricultural College Yangtze UniversityJingzhou 434025HubeiChina

Reliance on agriculture for food security is a constant in all modern *** climate change and population growth have put immense pressure on sustainable agriculture,exacerbating the effects of environmental *** is one of the most pressing abiotic stresses that farmers face,presenting an annual threat to crop growth and *** have evolved extensive morphological,physiological,and molecular mechanisms to combat drought *** resistance is a polygenic trait,controlled by a complex genetic network and an array of genes working together to ensure plant *** studies have aimed at dissecting the genetic mechanisms underlying drought *** studies using linkage and association mapping have made progress in identifying genetic variations that affect drought-resistance *** loci may potentially be engineered by genetic transformation and genome editing aimed at developing new,stress-resistant crop *** we summarize recent progress in elucidating the genetic basis of crop drought ***-breeding technologies such as marker-assisted selection,genome selection,gene transformation,and genome editing are currently employed to develop drought-resistant germplasm in a variety of *** advances in basic research and crop biotechnology covered in this review will facilitate delivery of drought-resistant crops with unprecedented efficiency.

关键词： Drought resistance QTL GWAS Molecular breeding

An Objective Identification Method for Wintertime Cold Fronts in Eurasia

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Advances in Atmospheric Sciences 2021年第10期38卷 1695-1705页

作者： Mengru feng Yujing qin Chuhan LU Key Laboratory of Meteorological Disaster Ministry of Education/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjing 210044China

The present study identifies wintertime cold fronts in Eurasia from gridded datasets using a new objective two-step identification *** simple and classic conception of a front is adopted,where a cold front is identified as the warm boundary of the frontal zone with a suitable horizontal temperature gradient and cold *** combine the traditional thermal front parameter with temperature advection to first identify the cold frontal zone,and then its eastern and southern boundaries are objectively plotted as a cold front in *** comparing different cold front identification methods,the results from this two-step cold front identification method and subjective analysis are more consistent,and the positions of the cold front identified with our method are more *** objective technique is also applied to a nationwide cold wave event over *** show that the horizontal extent and movement of the cold front are in good agreement with the related circulation and the associated cold *** proposed method and results in this study may shed light on the rapid identification of cold fronts in operational weather analysis and facilitate further research on the long-term activity characteristics of continental cold fronts.

关键词： cold front thermal front parameter objective identification Eurasia winter

Effects and mechanisms of acupuncture on women related health

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Frontiers of Medicine 2024年第1期18卷 46-67页

作者： Huichao qin Jiaxing feng Xiaoke Wu Department of Reproductive Medicine Heilongjiang Provincial HospitalHarbin Institute of TechnologyHarbin150036China Department of Obstetrics and Gynecology First Affiliated HospitalHeilongjiang University of Chinese MedicineHarbin150040China

Globally,public health interventions have resulted in a 30-year increase in women’s life ***,women’s health has not increased when socioeconomic status is ***’s health has become a major public health concern,for those women from developing countries are still struggling with infectious and labor-related diseases,and their counterparts in developed countries are suffering from physical and psychological *** recent years,complementary and alternative medicine has attracted wide attentions with regards to maintaining women’s ***,a crucial component of traditional Chinese medicine,has been used to treat many obstetric and gynecological diseases for thousands of years due to its analgesic and anti-inflammatory effects and its effects on stimulating the sympathetic/parasympathetic nervous *** fully understand the mechanism through which acupuncture exerts its effects in these diseases would significantly extend the list of available interventions and would allow for more reasonable advice to be given to general ***,by searching PubMed and CNKI regarding the use of acupuncture in treating obstetric and gynecological diseases,we aimed to summarize the proven evidence of using acupuncture in maintaining women’s health by considering both its effectiveness and the underlying mechanisms behind its effects.

关键词： acupuncture women health clinical efficacy mechanism

Pd/TiN nanocomposite catalysts for selective hydrogenation of phenol and its derivatives

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Chinese Chemical Letters 2016年第9期27卷 1500-1504页

作者： Hai-feng Li qin-sheng Zhang Zeng-Bo Pang Mi Tian Ping Gao Lai-Lai Wang State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China Graduate University of Chinese Academy of Sciences Beijing 100039 China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

Pd/TiN nanocomposite catalysts were fabricated for one-step selective hydrogenation of phenol to cyclohexanone successfully. High conversion of phenol （99%） and selectivity of cyclohexanone （98%） were obtained at 30 ℃ and 0.2 MPa H2 for 12 h in the mixed solvents of H20 and CH2C12. The Pd nanoparticles were stable in the reaction, and no aggregation was detected after four successive runs. The catalytic activity and selectivity depended on slightly the Pd particle sizes. The generality of the catalysts for this reaction was demonstrated by the selective hydrogenation of phenol derivatives, which showed that the catalyst was selective for the formation of cyclohexanone.

关键词： Phenol Hydrogenation Cyclohexanone TiN support Pd/ TiN catalysts

Dioxygen Affinities and Catalytic Oxidation Performance of Co （Ⅱ） Complexes with Phenol Ether Bridged Dihydroxamic Acids

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Chinese Chemical Letters 2006年第9期17卷 1259-1262页

作者： Xing Yue WEI sheng Ying qin College of Environmental and Biological Engineering Chongqing Technology and Business University Chongqing 400067 Department of Chemistry Sichuan-University Chengdu 610064

The oxygenation constants and thermodynamic parameter （△H°, △S°） of a series of novel Co （Ⅱ） complexes with phenol ether bridged dihydroxamic acids CoL^1-CoL^6 were measured, their catalytic performance in oxidation of p-xylene to p-toluic acid （PTA） were examined. The modulation of O2-binding capabilities and catalytic oxidation activities by X （X = Cl, OCH3） and Y （Y = H, CH3, Cl） groups bonded to the aromatic rings of the Co （Ⅱ） complexes were investigated.

关键词： Cobalt(Ⅱ) complexes dioxygen affinities catalytic oxidation p-xylene

Preliminary limits of a logarithmic correction to the Newtonian gravitational potential in binary pulsars

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Research in Astronomy and Astrophysics 2014年第10期14卷 1301-1306页

作者： Chang Lu Zi-Wei Li sheng-feng Yuan Zhen Wan Song-He qin Kai Zhu Yi Xie School of Astronomy and Space Science Nanjing University Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityMinistry of Education

We obtain preliminary limits on a logarithmic correction to the Newtonian gravitational potential by using five binary pulsars： PSR J0737-3039, PSR B 1534＋12, PSR J 1756-2251, PSR B 1913＋ 16 and PSR B2127＋ 11C. This kind of correction may originate from fundamental frameworks, like string theories, effective models of grav- ity due to quantum effects and the non-local gravity scheme. We estimate the upper limit of the Tohline-Kuhn-Kruglyak parameter A and the lower limit of the Fabris- Campos parameter α, which parameterize the correction and are connected to each other by αλ = -1. By analyzing the advances of periastron of these binary pulsars, we find that the preliminary upper limit of a is 0.19 ± 0.14 kpc^-1 and the prelimi- nary lower limit of ）, is -5.2 4± 3.8 kpc. They are compatible with the bounds based on dynamics of spiral galaxies but quite different from those given by solar system dynamics. These results indicate that this logarithmic correction might be more ob- servable in current timings of binary pulsars than in motions of the solar system.

关键词： gravitation -- relativity -- pulsars individual (PSR 0737-3039, PSRB 1534+12, PSR J1756-2251, PSR B1913+16, PSR B2127+11C)