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41.
分布式电源的选址与定容是微电网研究所面临的重要问题,本文主要考虑规划地区的24-h负荷时序特性和气候特点的24-h负荷变换的情况下的DG优化配置。针对以上问题,通过链式多智能体遗传算法对其进行优化处理。首先通过算法对IEEE33节点系统进行测试,验证算法在分布式电源优化配置中的优越性,并对PG E69节点配电网进行24-h时序的全过程模拟仿真优化,结果验证了多智能体遗传算法能在分布式电源配置上的有效性,同时提高微电网接入的预测精度,加快收敛速度,改进陷入局部最优的可能性等问题,对微电网在规划选址与定容选择上提供工程参考的实用性。 相似文献
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Wen J Zhao H Lv L Yuan B Wang G Wen X 《The Journal of the Acoustical Society of America》2011,130(3):1201-1208
Recently, by introducing locally resonant scatterers with spherical shape proposed in phononic crystals into design of underwater sound absorption materials, the low-frequency underwater sound absorption phenomenon induced by the localized resonances is observed. To reveal this absorption mechanism, the effect of the locally resonant mode on underwater sound absorption should be studied. In this paper, the finite element method, which is testified efficiently by comparing the calculation results with those of the layer multiple scattering method, is introduced to investigate the dynamic modes and the corresponding sound absorption of localized resonance. The relationship between the resonance modes described with the displacement contours of one unit cell and the corresponding absorption spectra is discussed in detail, which shows that the localized resonance leads to the absorption peak, and the mode conversion from longitudinal to transverse waves at the second absorption peak is more efficient than that at the first one. Finally, to show the modeling capability of FEM and investigate shape effects of locally resonant scatterers on underwater sound absorption, the absorption properties of viscoelastic materials containing locally resonant scatterers with ellipsoidal shape are discussed. 相似文献
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Enhanced targeted energy transfer for adaptive vibration suppression of pipes conveying fluid 总被引:1,自引:0,他引:1
Nonlinear Dynamics - In this paper, a nonlinear energy sink and a negative stiffness element are integrated for achieving enhanced, passive, and adaptive vibration suppression for a pipe conveying... 相似文献
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Yingfen Li Xian Wei Song Bai Zhi‐Gang Xu Menglan Lv 《Journal of heterocyclic chemistry》2019,56(12):3429-3434
The skeleton of fused benzimidazole‐pyrazine was constructed via an Ugi/deprotection/cyclization (UDC) and hydroamination cascade reaction. This four‐step reaction was carried out in a one‐pot procedure with only one‐time column chromatography purification. The representative compound 7b exhibited 67% cell growth inhibitory activity against human breast cancer cell line MDA‐MB‐453 at the concentration of 10μM. 相似文献
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In this paper, we establish an extension of Funk's section theorem. Our result has the following corollary: If is a star body in whose central -slices have the same volume (with appropriate dimension) as the central -slices of a centered body , then the dual quermassintegrals satisfy , for any , with equality if and only if . The case that is a centered body implies Funk's section theorem.
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Let H be a hereditary algebra of Dynkin type D n over a field k and 𝒞 H be the cluster category of H. Assume that n ≥ 5 and that T and T′ are tilting objects in 𝒞 H . We prove that the cluster-tilted algebra Γ = End𝒞 H (T)op is isomorphic to Γ′ = End𝒞 H (T′)op if and only if T = τ i T′ or T = στ j T′ for some integers i and j, where τ is the Auslander–Reiten translation and σ is the automorphism of 𝒞 H defined in Section 4. 相似文献