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Sensitivity of the Size of a TC to Sea Surface Temperatures in Its Outer Region

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Journal of Meteorological Research 2023年第6期37卷 829-840页

作者： Mingyu bi Tim LI Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing210044China Key Laboratory for Typhoon Monitoring&Forecasting of Zhejiang Province Wenzhou325000China International Pacific Research Center and Department of Atmospheric Sciences University of Hawaii at ManoaHonoluluHawaii96822USA

We investigated the sensitivity of the size of a tropical cyclone(TC) to warming or cooling sea surface temperatures(SST) in its outer region by simulating the SST beyond a radius of 200 km from the TC *** experiments showed that an increased SST outside the core region of the TC had a negative effect on its *** in the outer region contributed to the local enhancement of the latent heat flux from sea surface,which promoted the development of small-scale convection and warmed the lower and *** warming altered the local pressure gradient force in the upper and lower troposphere in such a way that it weakened the secondary circulation of the TC and led to suppression of the spiral rainbands outside the *** analysis showed that the outward-propagating rainband structure favored an increase in the size of the *** diabatic heat released by the rainbands induced an inflow at lower levels,facilitating expansion of the *** greater the distance of the rainbands from the center of the TC,given the same amplitude of diabatic heating,the stronger the forced inflow,resulting in a faster increase in the size of the TC.

关键词： tropical cyclones(TCs) size rainbands sea surface temperature(SST)

Functions of chromatin remodeling factors in heterochromatin formation and maintenance

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Science China(Life Sciences) 2012年第1期55卷 89-96页

作者： bi Xin Department of biology University of Rochester Rochester NY 14627 USA

Heterochromatin is characteristically more compact than chromatin is mediated by special histone modifications, euchromatin in the eukaryotic genome. The establishment of hetero- recruitment and propagation of heterochromatin specific proteins, as well as formation of special primary and high order structures of chromatin. Chromatin remodeling factors are ATPases that can alter the conformation and/or positioning of nucleosomes along DNA in an ATP-dependent manner. There is increasing evidence implicating chromatin remodeling activities in heterochromatin in various organisms ranging from yeasts to humans. Chromatin remodeling factors play roles in the establishment, maintenance and epigenetic inheritance of heterochromatin, but the underlying molecular mechanisms have just begun to be investigated.

关键词： chromatin remodeling gene silencing heterochromatin inheritance nucleosome replication

Rectangle expansion A* pathfinding for grid maps

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Chinese Journal of Aeronautics 2016年第5期29卷 1385-1396页

作者： Zhang An Li Chong bi Wenhao School of Aeronautics Northwestern Polytechnical University School of Electronics and Information Northwestern Polytechnical University

Search speed, quality of resulting paths and the cost of pre-processing are the principle evaluation metrics of a pathfinding algorithm. In this paper, a new algorithm for grid-based maps, rectangle expansion A＊（REA＊）, is presented that improves the performance of A＊ significantly. REA＊ explores maps in units of unblocked rectangles. All unnecessary points inside the rectangles are pruned and boundaries of the rectangles （instead of individual points within those boundaries） are used as search nodes. This makes the algorithm plot fewer points and have a much shorter open list than A＊. REA＊ returns jump and grid-optimal path points, but since the line of sight between jump points is protected by the unblocked rectangles, the resulting path of REA＂ is usually better than grid-optimal. The algorithm is entirely online and requires no offline pre-processing. Experimental results for typical benchmark problem sets show that REA＊ can speed up a highly optimized A＊ by an order of magnitude and more while preserving completeness and optimality. This new algorithm is competitive with other highly successful variants of A＊.

关键词： Breaking path symmetries Grid Heuristic algorithms Path search Variant of A*

Institute of Metal Research,Chinese Academy of Sciences:aiming to achieve breakthroughs in the development of materials

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National Science Review 2017年第2期4卷 269-282页

作者： Lei bi 机构不详

INTRODUCTION History Institute of Metal Research(IMR),which was founded in Shenyang in1953,is among the earliest institutes established by the Chinese Academy of Sciences(CAS) subsequently to the founding of the Peopl... 详细信息

关键词： high Institute of Metal Research,Chinese Academy of Sciences:aiming to achieve breakthroughs in the development of materials

Combination method of conflict evidences based on evidence similarity

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Journal of Systems Engineering and Electronics 2017年第3期28卷 503-513页

作者： Wenhao bi An Zhang Yuan Yuan School of Aeronautics Northwestern Polytechnical UniversityXi’an 710129China

Aiming at the problem that the traditional Dempster Shafer (D-S) evidence theory cannot deal with conflicted evidences effectively and correctly, this paper points out that the key issue of this problem is to measure the degree of conflict between evidences correctly after analyzing various improved methods. The existing evidence conflict measure methods are analyzed, and a new evidence conflict measure method called evidence similarity measure based on the Tanimoto measure is proposed, while a new evidence combination method is proposed on the basis of evidence similarity measure. Firstly, the conflict degrees between evidences are obtained through the evidence similarity measure. Then the evidence sources are modified based on the credibility of different evidences and the weights of conflicted parts of evidences on different focal elements are determined. Finally, the fusion result is obtained by this method. Numerical examples show that the proposed method can effectively fuse evidences when evidences are consistent or highly conflicted, and it has a fast convergence speed, a high degree of accuracy and good adaptability.

关键词： evidence theory evidence conflict conflict measure evidence similarity information fusion

Synthesis of 14-aryl or alkyl-14H-dibenzo[a,j]xanthenes promoted by Mg(HSO_4)_2

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Chinese Chemical Letters 2011年第1期22卷 45-48页

作者： bi bi Fatemeh Mirjalili Abdolhamid Bamoniri Ali Akbari Department of Chemistry College of ScienceYazd UniversityYazdP.O.Box 89195-741Iran Department of Organic Chemistry Faculty of ChemistryUniversity of KashanKashanIran

14-Aryl or alkyl-14H-dibenzo[a,j]xanthenes were prepared by condensation of 2-naphthol and aldehydes in the presence of Mg（HSO4）2 as an efficient, cheap, readily available and eco-friendly catalyst. This procedure h... 详细信息

关键词： 14-Aryl or alkyl-14H-dibenzo [a,j]xanthene Mg(HSO4)2 Xanthenes 2-Naphthol Ultrasound

Modular assembly of Co4-thiacalix[4]arene units and Keggin-type SiW12O40 for visible-light photothermal conversion

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Tungsten 2025年第1期 112-119页

作者： Jia-Hui Li Qing Zhao Dong-Ao Mao Kun Zhou Bao-Kuan Chen Yan-Feng bi School of Petrochemical Engineering Liaoning Petrochemical University

The construction of metal-organic coordination clusters（MCCs） using modular secondary building units is an important method for preparing functional *** this study,two new MCCs modularly assembled from Keggin-type {SiW12O40}H4TC4A=p-tert-Butylthiacalix[4]arene(SiW12) units and thiacalixarene-supported Co4-thiacalix[4]arene(Co4-TC4A polynuclear second-building units（PSBUs,H4TC4A=p-tert-Butylthiacalix[4]arene） are *** two MCCs,abbreviated as Co4-SiW12and Co8-SiW12,were structurally characterized by single-crystal X-ray *** Co4-SiW12is a supramolecular structure involving cation-anion interactions between Co4-TC4A PSBUs and ***8-SiW12features "barbell-like" shapes with two Co4-TC4A coordinatively linked to a Keggin-type SiW12unit on opposite via W-O_t-Co *** coordination of Co4-TC4A to SiW12in Co8-SiW12resulted in significantly improved photothermal conversion performances compared with Co4-SiW12and pure SiW12or ***-gap determination and photophysical analysis combined with density functional theory calculations indicated the binding mode between Co4-TC4A PSBUs and SiW12,which considerably influences the way of electron transport and the conversion ability of visible light to heat.

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Multi-layer analytic solution for k-ωmodel equations via a symmetry approach

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Applied Mathematics and Mechanics(English Edition) 2023年第2期44卷 289-306页

作者： Fan TANG Weitao bi Zhensu SHE Department of Mechanics and Engineering Science College of EngineeringPeking UniversityBeijing 100871China State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing 100871China

Despite being one of the oldest and most widely-used turbulence models in engineering computational fluid dynamics(CFD),the k-ωmodel has not been fully understood theoretically because of its high nonlinearity and complex model parameter ***,a multi-layer analytic expression is postulated for two lengths(stress and kinetic energy lengths),yielding an analytic solution for the k-ωmodel equations in pipe *** local balance equations are analyzed to determine the key parameters in the solution,which are shown to be rather close to the empirically-measured values from the numerical solution of the Wilcox k-ωmodel,and hence the analytic construction is fully *** results provide clear evidence that the k-ωmodel sets in it a multilayer structure,which is similar to but different,in some insignificant details,from the Navier-Stokes(N-S)*** finding explains why the k-ωmodel is so popular,especially in computing the near-wall ***,the analysis is extended to a newlyrefined k-ωmodel called the structural ensemble dynamics(SED)k-ωmodel,showing that the SED k-ωmodel has improved the multi-layer structure in the outer flow but preserved the setting of the k-ωmodel in the inner region.

关键词： turbulence model k-ωmodel structural ensemble dynamics(SED) multilayer structure symmetry

Surface Integrity of Inconel 738LC Parts Manufactured by Selective Laser Melting Followed by High-speed Milling

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Chinese Journal of Mechanical Engineering 2023年第1期36卷 65-79页

作者： Guanhui Ren Sai Guo bi Zhang Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen518055China Shenzhen Key Laboratory for Additive Manufacturing of High-performance Materials Shenzhen518055China Research and Development Department Shenzhen Xinjinquan Precision Techonology Co.Ltd.Shenzhen518055China School of Mechanical Engineering Shandong UniversityJinan250061China

This study is concerned with the surface integrity of Inconel 738LC parts manufactured by selective laser melting(SLM)followed by high-speed milling(HSM).In the investigation process of surface integrity,the study employs ultradepth three-dimensional microscopy,laser scanning confocal microscopy,scanning electron microscopy,electron backscatter diffractometry,and energy dispersive spectroscopy to characterize the evolution of material microstructure,work hardening,residual stress coupling,and anisotropic effect of the building direction on surface integrity of the *** results show that SLM/HSM hybrid manufacturing can be an effective method to obtain better surface quality with a thinner machining metamorphic ***-speed machining is adopted to reduce cutting force and suppress machining heat,which is an effective way to produce better surface mechanical properties during the SLM/HSM hybrid manufacturing *** general,high-speed milling of the SLM-built Inconel 738LC samples offers better surface integrity,compared to simplex additive manufacturing or casting.

关键词： Surface integrity Inconel 738LC Selective laser melting High-speed milling