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Modeling Responses of Leafy Spurge Dispersal to Control Strategies

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Journal of Integrative Plant Biology 2007年第12期49卷 1681-1692页

作者： Zewei miao Grant F. Walton Center for Remote Sensing & Spatial Analysis Cook College Rutgers University New Brunswick NJ 08901-8551 USA

Leafy spurge （Euphorbia esula L.） has substantial negative effects on grassland biodiversity, productivity, and economic benefit in North America. To predict these negative impacts, we need an appropriate plant-spread model which can simulate the response of an invading population to different control strategies. In this study, using a stochastic map lattice approach we generated a spatially explicitly stochastic process-based model to simulate dispersal trajectories of leafy spurge under various control scenarios. The model integrated dispersal curve, propagule pressure, and population growth of leafy spurge at local and short-temporal scales to capture spread features of leafy spurge at large spatial and long-temporal scales. Our results suggested that narrow-, medium-, and fat-tailed kernels did not differ in their ability to predict spread, in contrast to previous works. For all kernels, Allee effects were significantly present and could explain the lag phase （three decades） before leafy spurge spread accelerated. When simulating from the initial stage of introduction, Allee effects were critical in predicting spread rate of leafy spurge, because the prediction could be seriously affected by the low density period of leafy spurge community. No Allee effects models were not able to simulate spread rate well in this circumstance. When applying control strategies to the current distribution, Allee effects could stop the spread of leafy spurge; no Allee effects models, however, were able to slow but not stop the spread. The presence of Allee effects had significant ramifications on the efficiencies of control strategies. For both Allee and no Allee effects models, the later that control strategies were implemented, the more effort had to be input to achieve similar control results.

关键词： Allee effects dispersal curve invasive species non-indigenous propagule pressure stochastic process-based model.

How can technology and efficiency alleviate the dilemma of economic growth and carbon emissions in China's industrial economy? A metafrontier decoupling decomposition analysis

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Petroleum Science 2024年第2期21卷 1415-1428页

作者： miao Wang Chao Feng School of Business Zhengzhou UniversityZhengzhou450001HenanChina School of Economics and Business Administration Chongqing UniversityChongqing400030China

This paper attempts to explore the decoupling relationship and its drivers between industrial economic increase and energy-related CO_(2) emissions(ICE). Firstly, the decoupling relationship was evaluated by Tapio index. Then, based on the DEA meta-frontier theory framework which taking into account the regional and industrial heterogeneity and index decomposition method, the driving factors of decoupling process were explored mainly from the view of technology and efficiency. The results show that during2000-2019, weak decoupling was the primary state. Investment scale expansion was the largest reason hindering decoupling process of industrial increase from ICE. Both energy saving and production technology achieved significant progress, which facilitated the decoupling process. Simultaneously, the energy technology gap and production technology gap among regions have been narrowed, and played a role in promoting decoupling process. On the contrary, both scale economy efficiency and pure technical efficiency have inhibiting effects on decoupling process. The former indicates that the scale economy of China's industry was not conducive to improve energy efficiency and production efficiency, while the latter indicates that resource misallocation problem may exist in both energy market and product market.

关键词： China's industrial sector Decoupling process Meta-frontier DEA Index decomposition method Driving factors

Strichartz Estimates for Schr(?)dinger Equations with Non-degenerate Coefficients

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Chinese Annals of Mathematics,Series B 2007年第5期28卷 555-570页

作者： Yu miao School of Mathematical Sciences Pudan University Shanghai 200433 China.

In the present paper, the full range Strichartz estimates for homogeneous Schroedinger equations with non-degenerate and non-smooth coefficients are proved. For inhomogeneous equation, the non-endpoint Strichartz esti... 详细信息

关键词： Schroedinger equation Strichartz estimates Parametrix

Averages of shifted convolution sums for arithmetic functions

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Frontiers of Mathematics in China 2019年第1期14卷 123-134页

作者： miao LOU School of Mathematics Shandong University Jinan 250100 China

Let f be a full-level cusp form for GLm(Z) with Fourier coefficients Af(cm-2,…, c1, n): Let λ(n) be either the von Mangoldt function Λ(n) or the k-th divisor function τk(n): We consider averages of shifted convolu... 详细信息

关键词： Average shifted convolution sum arithmetic function

In-situ growth of porous Cu_(3)(BTC)_(2) on cellulose nanofibrils for ultra-low dielectric films with high flexibility

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Journal of Materials Science & Technology 2022年第17期112卷 202-211页

作者： Rui Liu Xiang He miao miao Shaomei Cao Xin Feng Department of Chemistry College of SciencesShanghai UniversityShanghai 200444China Research Center of Nano Science and Technology College of SciencesShanghai UniversityShanghai 200444China

The design of flexible polymeric films with internal porous structures has received increasing attention in low dielectric *** highly porous metal-organic frameworks(MOFs)of[Cu_(3)(BTC)_(2)]_(n)(BTC=benzene-1,3,5-tricarboxylate)were introduced into aramid nanofibers(ANF)matrix by using carboxylated cellulose nanofibrils(CNF)as carriers to obtain strong,flexible,and ultra-low dielectric *** well-dispersed“flowers-branch”like CNF@CuBTC through in-situ growth of CuBTC on CNF surface endowed the ANF/CNF@Cu BTC films with excellent thermal stability,mechanical integrity and low dielectric ***,the flexible dielectric films exhibited superior ultraviolet(UV)resistance,lower coefficient of thermal expansion(4.28×10^(-5)℃^(-1))and increased water contact angle(83.81°).More interestingly,the removal of guest molecules from the ANF/CNF@CuBTC films according to the vacuum heat treatment(VHT)process significantly improved their dielectric *** specific surface areas of the composite films after VHT increased obviously,and the dielectric constant and dielectric loss tangent decreased to the expected 1.8-2.2 and 0.001-0.03 at 100 MHz,***,such designable ultra-low dielectric films with high flexibility play an incredible significance in applications of microelectronics under large deformation conditions,especially in flexible/wearable devices at the arrival of 5 G era.

关键词： Aramid nanofibers Carboxylated cellulose nanofibrils Vacuum heat treatment Dielectric properties Metal-organic frameworks

INTERACTION OF THREE PARALLEL CRACKS IN RECTANGULAR PLATE UNDER CYCLIC LOADS

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Acta Mechanica Solida Sinica 2013年第5期26卷 519-535页

作者： Changqing miao Xiangqiao Yan Research Laboratory for Composite Materials Harbin Institute of Technology

This paper presents a numerical approach for modeling the interaction between multiple cracks in a rectangular plate under cyclic loads. It involves the formulation of fatigue growth of multiple crack tips under ruixed-mode loading and an extension of a hybrid displacement discontinuity method （a boundary element method） to fatigue crack growth analyses. Because of an intrinsic feature of the boundary element method, a general growth problem of multiple cracks can be solved in a single-region formulation. In the numerical simulation, remeshing of existing boundaries is not necessary for each increment of crack extension. Crack extension is conveniently modeled by adding new boundary elements on the incremental crack extension to the previous crack boundaries. As an example, the numerical approach is used to analyze the fatigue growth of three parallel cracks in a rectangular plate. The numerical results illustrate the validation of the numerical approach and can reveal the effect of the geometry of the cracked plate on the fatigue growth.

关键词： mixed-mode crack fatigue crack growth crack-tip element displacement discon-tinuity method

Fuzzy color morphological sieves

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Journal of Systems Engineering and Electronics 2009年第6期20卷 1366-1372页

作者： Yang miao Wei Zhiqiang Dept. of Electronic Engineering Huaihai Inst. of Technology Lianyungang 222006 P. R. China Dept. of Computer Science Ocean Univ. of China Qingdao 266061 P. R. China

To solve the problems that exist in the color morphological sieves, a new fuzzy color morphological sieve is *** method adopts color fuzzy model to define extrema and selects more rational regional merging way to produce better *** can deal with the maxima or the minima areas respectively and the approach is simple and agile in *** color fuzzy model and the steps of the algorithm are *** evaluation of the performance shows the new method can produce the best synthetical performance.

关键词： color image processing morphological sieves fuzzy mathematics hierarchical analysis.

Water use strategies of the desert riparian forest plant community in the lower reaches of Heihe River Basin, China

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Science China Earth Sciences 2014年第4期57卷 1293-1305页

作者： FU aihong CHEN YaNing LI WeiHong State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences

The object of this paper is the different plant communities in the Ejina desert riparian forest. Groundwater depth, soil moisture, plant water potential, relative leaf moisture content and water use efficiency was monitored, and the response of soil moisture and plant ecology to the groundwater depth and the water use efficiency of the different plant communities was analyzed. The results showed that：（1） Along with the groundwater depth increasing, predawn and midday water potential of the plants, with the exception of Reaumuria soongorica, did not decrease significantly, indicating that when the groundwater depth is less than 3 m, the plant communities in the range of 4 km from the river way did not suffer or slightly suffer from water stress;（2） The distribution of higher soil moisture content within 0–3 m soil layer is suitable with the plants’ root system, as indicated in the communities of coexisting overripe Populus euphratica or Taramrix chinensis, both of which can release excessive water into soil for shallow rooted shrubs or herbaceous plants when there is water shortage;（3） R. soongorica can absorb deep soil moisture through deep roots for their own survival;（4） The community consisting of Sophora alopecuroides, Karelinia caspica, T. chinensis, and overripe P. euphratica has the best species combination for restoring the damaged eco-environment in the lower reaches of Heihe River;（5） The order of plants’ relative leaf water contents is K. caspica ＆gt; S. alopecuroides ＆gt; young P. euphratica ＆gt; overripe P. euphratica ＆gt; mature P. euphratica = T. chinensis coexisting with other species ＆gt; single R. soongorica ＆gt; single T. chinensis and the order of WUE is single T. chinensis ＆gt; single R. soongorica ＆gt; T. chinensis living in symbiosis with other species ＆gt; S. alopecuroides = young P. euphratica ＆gt; mature P. euphratica ＆gt; overripe P. euphratica ＆gt; K. caspica. Therefore, with ample soil moisture, the plant community helps rapid growth of

关键词： water potential soil moisture water use efficiency water use strategy desert riparian forest Heihe river

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Index Estimates for Free Boundary f-minimal Hypersurfaces

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Acta Mathematica Sinica,English Series 2023年第9期39卷 1727-1735页

作者： Niang Chen Jian Quan Ge miao miao Zhang School of Mathematical Sciences Laboratory of Mathematics and Complex SystemsBeijing Normal UniversityBeijing100875P.R.China

We prove that the index is bounded from below by a linear function of its first Betti number for any compact free boundary f-minimal hypersurface in certain positively curved weighted manifolds.

关键词： Index f-minimal hypersurfaces free boundary the first Betti number