Results 11 to 20 of about 886 (138)

A new method for broad‐scale modeling and projection of plant assemblages under climatic, biotic, and environmental cofiltering

open access: yesConservation Biology, Volume 36, Issue 2, April 2022., 2022
Abstract There is increasing interestin broad‐scale analysis, modeling, and prediction of the distribution and composition of plant species assemblages under climatic, environmental, and biotic change, particularly for conservation purposes. We devised a method to reliably predict the impact of climate change on large assemblages of plant communities ...
Alessandro Ferrarini   +3 more
wiley   +1 more source

Spatiotemporal Characteristics of Carbon Storage and Its Response to Land Use Changes in Fujian Province [PDF]

open access: yes, 2023
[Objective] The ecosystem carbon storage and its response to land use changes in Fujian Province were analysed in order to provide a reference for ecosystem protection.
Lin Yingbing   +3 more
core   +1 more source

Efficient algorithm for computing Walsh spectrum and differential probability [PDF]

open access: yes, 2015
According to the characteristic of T-functions,along with the definition of narrow T-functions,the linear prop-erty and differential property were studied.Markov chain and transition matrices were constructed to propose fast algo-rithm for computing ...
IUYan L, UBin H, ULi-ping X
core   +1 more source

Temporal and Spatial Changes of Land Use and Their Eco-environmental Effects in Nanchang City from 2000 to 2020 [PDF]

open access: yes, 2022
[Objective] The regional ecological environmental effects caused by land use changes in Nanchang City by determining the quantitative relationships between regional land and resource development and ecological environments were analyzed in order to ...
Tang Jianglong   +2 more
core   +1 more source

Spatial-temporal Evolution and Prediction of Ecosystem Carbon Storage on Hainan Island by Coupling InVEST and FLUS Models [PDF]

open access: yes, 2023
[Objective] The influence of land use changes on carbon storage were studied under the expansion of urbanization in Hainan Island to reveal the spatial-temporal evolution pattern of carbon storage and to predict future development trends in order to ...
Chen Xu   +5 more
core   +1 more source

贵州省农业与气象干旱特征及其响应关系

open access: yesShuitu Baochi Xuebao, 2022
利用贵州省1980-2020年逐月降水与土壤水分计算标准化降水指数(SPI)和标准化土壤水分指数(SSI),基于游程理论、传播响应率(Rr)、状态转移概率矩阵等方法探究气象与农业干旱特征变化,以及两者之间的响应关系。结果表明:(1)贵州省农业干旱较气象干旱持续时间长、烈度大,干旱历时空间变化较气象干旱显著,干旱烈度则较单一。(2)季尺度上,春季农业干旱对气象干旱响应最为敏感,夏、秋季次之,冬季较弱;不同地貌类型下,春、冬季在半喀斯特低中山响应程度较高,夏季在峰丛谷地,秋季在非喀斯特地区;不同切割深度下 ...
游漫   +4 more
doaj  

Improvement of the Hopfield Neural Network and Transfer-matrix calculation of positional distribution in the 2-dimensional semiflexible polymer [PDF]

open access: yes, 2006
摘要本文主要分为两个部分,第一部分为用蒙特卡罗变异优化选择规则优化Hopfield神经网络,第二部分为转移矩阵在二维半柔软聚合物研究中的应用。第一部分研究表明蒙特卡罗变异优化选择规则可以用来优化神经网络的性能。在第一部分我们以Hopfield网络为例,运用蒙特卡罗变异优化选择规则在保持网络的整体结构基本不变的情况下,优化Hopfield神经网络的动力学特性,提高网络的存储功能和存储质量。在优化后的网络中,每个记忆模式都被严格设计成网络的不动点吸引子,从而每个模式都能够被精确联想 ...
周震
core   +1 more source

黄河流域上游城市群三生空间时空演化特征及其变化稳定性分析

open access: yesShuitu Baochi Xuebao, 2023
识别三生空间迁移演化规律并掌握其引发的空间性状改变情况,对优化国土空间布局、提高利用水平影响深远。以黄河流域上游城市群为研究对象,基于转移矩阵对研究区2000—2020年三生空间时空演化规律进行分析,并以此为基础,利用强度分析模型,从三生空间一、二级分类双重视角,就空间演化带来的变化稳定性问题进行讨论。结果表明:(1)20年间,研究区三生空间转移变化活跃但发生数量和规模均呈缩减态势,空间转移以呼包鄂榆和宁夏沿黄城市群两地为主,呈东多西少分布特征,但以生态为主、生产和生活空间为辅的整体格局未发生改变。(2)
黄鑫   +5 more
doaj  

Multiview Spectral Clustering Based on Weighted Tensor Low-Rank Constraint [PDF]

open access: yes
Many existing multiview clustering methods fail to simultaneously exploit the high-order correlations embedded in different views and the global geometric structure of each single view, resulting in inadequate clustering performance.
Sihui LIU, Quanxue GAO, Wei SONG, Deyan XIE
core   +1 more source

Spatiotemporal Coupling Relationship Between Plateau Pika Disturbance and Alpine Meadow Degradation [PDF]

open access: yes, 2023
[Objective] Plateau pika (Ochotona curzoniae) is a key species in the alpine meadow ecosystem of the Qinghai-Xizang Plateau. The coupling relationship between pika activity and meadow degradation was analyzed in order to further improve the observation ...
Gao Chongyue   +5 more
core   +1 more source

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