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排序方式： 共有294条查询结果，搜索用时 10 毫秒
1.
该文主要分析和探讨了差分进化算法(Differential Eveolutionary Algorithm,DE)在Riemannian流形中的几何关系,对P_ε条件下Riemannian流形中的种群个体进行了收敛性分析,得到了迭代个体收敛精度与收敛速度的量子不确定渐进估计,如下式△2n·△2xεβ(√(λε)1+…+... 相似文献
2.
Dawei Zhang;Yun Huang;Chufen Wu;Jianshe Yu; 《Studies in Applied Mathematics》2024,152(4):1456-1477
This paper is concerned with a free boundary problem with resource-dependent motility in a weak heterogeneous environment. The existence and uniqueness of global solutions are discussed first. Next, we establish long-time behaviors of solutions which is a spreading–vanishing dichotomy. Moreover, we obtain sharp criteria on spreading and vanishing by investigating the associated linearized eigenvalue problem. The theoretical analyses reveal an important biological phenomenon. (i) Resource abundance reduces the motility, providing advantages for individuals to persist in a habitat. (ii) Resource shortage enhances the motility, forcing individuals to expand outward to survive in an environment. Consequently, resource-dependent motility is more beneficial to the survival of species compared with random dispersal. 相似文献
3.
Zhaosheng Feng;Yu Su; 《Studies in Applied Mathematics》2024,153(2):e12723
In this paper, we are concerned with ground state solutions to fractional equations with Coulomb potential and critical exponent. The existence of ground state solutions is established under certain conditions by proposing a new analytical method. 相似文献
4.
This paper reports a hidden chaotic system without equilibrium point. The proposed system is studied by the software of MATLAB R2018 through several numerical methods, including Largest Lyapunov exponent, bifurcation diagram, phase diagram, Poincaré map, time-domain waveform, attractive basin and Spectral Entropy. Seven types of attractors are found through altering the system parameters and some interesting characteristics such as coexistence attractors, controllability of chaotic attractor, hyperchaotic behavior and transition behavior are observed. Particularly, the Spectral Entropy algorithm is used to analyze the system and based on the normalized values of Spectral Entropy, the state of the studied system can be identified. Furthermore, the system has been implemented physically to verify the realizability. 相似文献
5.
该文主要研究了 k-Hessian方程的Dirichlet问题.利用Leggett-Williams不动点定理,得到了一些关于非平凡径向解的存在性与多解性结论. 相似文献
6.
Formylation is one of the newly discovered post-translational modifications in lysine residue which is responsible for different kinds of diseases. In this work, a novel predictor, named predForm-Site, has been developed to predict formylation sites with higher accuracy. We have integrated multiple sequence features for developing a more informative representation of formylation sites. Moreover, decision function of the underlying classifier have been optimized on skewed formylation dataset during prediction model training for prediction quality improvement. On the dataset used by LFPred and Formator predictor, predForm-Site achieved 99.5% sensitivity, 99.8% specificity and 99.8% overall accuracy with AUC of 0.999 in the jackknife test. In the independent test, it has also achieved more than 97% sensitivity and 99% specificity. Similarly, in benchmarking with recent method CKSAAP_FormSite, the proposed predictor significantly outperformed in all the measures, particularly sensitivity by around 20%, specificity by nearly 30% and overall accuracy by more than 22%. These experimental results show that the proposed predForm-Site can be used as a complementary tool for the fast exploration of formylation sites. For convenience of the scientific community, predForm-Site has been deployed as an online tool, accessible at http://103.99.176.239:8080/predForm-Site. 相似文献
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8.
Besides dispersion engineering, idler-band distributed fiber loss provides a new synthesis freedom to flatten and broaden the gain spectrum for a fiber-optic parametric amplifier. This interesting phenomenon is based on the fact that the power balance between signal and idler is broken by idler loss, which changes the power conversion process in four-wave-mixing. The pump-to-signal conversion efficiency is kept unchanged in spite of the loss. 相似文献
9.
同时考虑了Kudryashov方法和Khalil一致分数阶变换,构造了求解一致分数阶非线性微分方程精确解的新方法,并将其用于求解时间-空间一致分数阶Whitham-Boroer-Kaup方程,得到了Whitham-Boroer-Kaup方程新的精确解,验证了该方法的有效性和可行性. 相似文献
10.
《European Journal of Operational Research》2006,172(2):560-573
This paper describes a parametric family of utility functions for decision analysis. The parameterization embeds the HARA class in a four-parameter representation for the risk aversion function. The resulting utility functions can have only four shapes: concave, convex, S-shaped, and reverse S-shaped. This makes the family suited for both expected utility and prospect theory. The paper also describes an alternative technique to estimate the four parameters from elicited utilities, which is simpler than standard fitting by minimization of the mean quadratic error. 相似文献