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101.
This paper describes how the scenario aggregation principle can be combined with approximate solutions of the individual scenario problems, resulting in a computationally efficient algorithm where two individual Lagrangian-based procedures are merged into one. Computational results are given for an example from fisheries management. Numerical experiments indicate that only crude scenario solutions are needed. 相似文献
102.
Cunshuang Ma Xiang Wang Jiaqi Lan Jiyu Zhang Keming Song Jiacheng Chen Junmin Ge Weihua Chen 《Advanced functional materials》2023,33(5):2211821
The fundamental challenges that coexisted around sulfur cathode energy storage systems, are the severe polysulfide dissolution and low reactivity resulting in poor reversibility and short cycle life, specifically, in inexpensive sodium ion batteries. Herein, the solution-processed synthesis of ultra-high intimate contacted FeS2/S architecture is reported and evolution of the dynamic multistage coupling between the FeS2 and S in sodium–sulfur batteries is revealed. Atomic visualization and in situ spectroscopy conclude that: NaxFeS2 (0 <x ≤1) effectively captures sodium polysulfides and promotes the conversion of S8 to Na2S4 to Na2S2/Na2S; simultaneously, the presence of Na2S2/Na2S traps the continuous growth of iron grains during continuously discharging to 0.4 V, thereby boosting the reversibility and high capacity. Moreover, the density functional theory further analyses the unique coupling effect of Na2Sx with different intermediate states of FeS2. The electrode with unique structure and dynamic coupling exhibits outstanding cycle reversibility and extremely long life, which delivers a reversible capacity of 860 mAh g−1 after 1000 cycles with no capacity decay at 0.5 A g−1. Even under a practical areal capacity of 4 mAh cm−2, it still shows pretty-well cycling stability. 相似文献
103.
Several amino acid ester cyclohexyl phosphoramidates of AZT as anti-HIV prodrugs were synthesized and investigated by electrospray ionization tandem mass spectrometry (ESI-MS(n)). A novel methoxy group migration from the carbonyl group to the phosphoryl group was observed in ESI-MS2. This migration is believed to be a general pathway for ions with a methyl ester moiety at the gamma-position to a phosphoric acid moiety, which is assisted with metal ions such as Li(+), Na(+) and K(+). Coordination between metal ions with both the carbonyl oxygen and phosphoryl oxygen might be a key factor responsible for this migration. 相似文献
104.
Multimachine power system stabilizer based on optimal multistage fuzzy PID attendant honey bee mating optimization
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Homayoun Ebrahimian Abbas Rahimi Gollou Farshad Bayramzadeh Ali Rahimi 《Complexity》2016,21(6):234-245
This article presents a new strategy based on multistage fuzzy PID controller for damping power system stabilizer in multimachine environment using Honey Bee Mating Optimization (HBMO). The proposed technique is a new metaheuristic algorithm which is inspired by mating procedure of the honey bee. Actually, the mentioned algorithm is used recently in power systems which demonstrate the good reflex of this algorithm. Also, finding the parameters of PID controller in power system has direct effect for damping oscillation. Hence, to reduce the design effort and find a better fuzzy system control, the parameters of proposed controller is obtained by HBMO that leads to design controller with simple structure that is easy to implement. The effectiveness of the proposed technique is applied to single machine connected to infinite bus and IEEE 3–9 bus power system. The proposed technique is compared with other techniques through integral of the time multiplied absolute value of the error and figure of demerit. © 2015 Wiley Periodicals, Inc. Complexity 21: 234–245, 2016 相似文献
105.
H. P. Benson 《Journal of Optimization Theory and Applications》1989,60(3):353-373
Many decision-making situations involve multiple planners with different, and sometimes conflicting, objective functions. One type of model that has been suggested to represent such situations is the linear multilevel programming problem. However, it appears that theoretical and algorithmic results for linear multilevel programming have been limited, to date, to the bounded case or the case of when only two levels exist. In this paper, we investigate the structure and properties of a linear multilevel programming problem that may be unbounded. We study the geometry of the problem and its feasible region. We also give necessary and sufficient conditions for the problem to be unbounded, and we show how the problem is related to a certain parametric concave minimization problem. The algorithmic implications of the results are also discussed.This research was supported by National Science Foundation Grant No. ECS-85-15231. 相似文献
106.
John Garofalakis Eleftherios Stergiou 《International Journal of Communication Systems》2011,24(4):415-437
Here a novel analytical method for performance prediction estimation of single‐ and multi‐layer multistage interconnection networks (MINs) under multicast environments is presented. The ‘Cell Replication While Routing’ is used as a packet routing technique and the ‘full multicast’ mode as transmission policy is employed in all the MINs under study. This model is developed for single‐layer MINs and is extended and applied to special types of multi‐layer MINs, called semi‐layer MINs, which support mixed traffic patterns such as unicast and multicast in uniform traffic conditions. The results confirm the significant performance saturation of single‐layer MINs and the improvement of corresponding performance indicators by semi‐layer MINs. The proposed analytical framework is anticipated to be a very useful tool in evaluating the performance of semi‐layer MINs in designing more efficient QoS networks. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
107.
108.
旅游大规模定制(Tourism Mass Customization, TMC)模式实施的关键是通过对旅游供应链的调度优化处理旅游活动的“规模效应”与游客“个性化需求”之间的矛盾问题。运用经济学及模糊数学的理论方法分析并实现了TMC模式下存在的多阶段模糊规模效应量化处理。构建了引入规模效应量化的服务成本最小化、引入模糊时间窗的顾客满意度最大化及供应链协同度最大化为优化目标的TMC模式下多目标供应链调度优化模型。最后,通过蚁群算法实现TMC模式下多调度优化目标的求解并对优化效果进行对比研究。研究结果表明,TMC模式下供应链调度中旅游活动存在多阶段模糊规模效应并且可以量化处理;TMC模式中的规模效应具有合理的区间范围,旅游企业应注重规模效应与其他目标的均衡;蚂蚁算法在求解TMC模式下多目标优化问题方面不仅收敛速度快,而且通过对多调度目标优化效果的对比检验表明,性能稳健优良。 相似文献
109.
多级降压收集极入口电子速度分布研究与应用 总被引:1,自引:0,他引:1
研究了多级降压收集极入口电子速度分布理论,并设计实验获取了入口电子能量分布密度函数。利用能量分布密度函数构造比较真实的收集极仿真初始条件,仿真结果与实测数据有很好的一致性。较旧的仿真初始条件仿真结果有很大改善,为多级降压收集极的设计和优化提供了有效依据,从而提高行波管的效率。 相似文献
110.