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聚合的分布式能源可作为虚拟电厂（virtual power plant，VPP）在电力市场中提供辅助调频服务，来应对低碳经济下大规模可再生能源并网给电力系统稳定性带来的挑战。为了引导VPP参与调频辅助服务市场，对VPP所有者的经济激励尤为重要。研究了澳大利亚国家电力市场中调频辅助服务市场机制，针对配网侧聚合的住宅屋顶光伏和电池储能系统的VPP，以利润最大化为目标，提出了嵌入电池循环寿命模型的调频市场优化竞标策略和与风电合作的联合优化竞标策略。同时，根据讨价还价博弈理论，基于Nash-Harsanyi 讨价还价解提出了一种反映VPP真实价值的合作剩余分配策略。算例结果验证了所提模型和方法的有效性，研究成果为激发VPP潜在价值提供了一条途径。

Carbon fiber reinforced composites, as a kind of high-performance composite material, possess many advantages like light weight, high specific strength and specific modulus, good resistance to corrosion and chemical stability. They have been widely used in aerospace, automotive industry and sports equipment, etc., and have become a research hotspot in the past few decades. Most carbon fiber reinforced composites are fabricated as laminated structures. Compared to the in-plane directions, there are no fibers in the thickness direction; therefore, the interlaminar properties are relatively poor, which have lower strength and toughness. Delamination and crack propagation damage will easily happen when subjected to load, which directly affects the loading capability. Besides, carbon fiber reinforced composites generally have lower damping properties dur to their high stiffness, resulting in that the tiny cracks in many engineering structures fabricated by carbon fiber reinforced composites, including military equipment, automotive and aircraft parts, etc., will gradually propagate due to the fatigue loading caused by the vibration during daily use, leading to premature failure. Therefore, domestic and foreign scholars have carried out a lot of related research work and also proposed some effective solutions in recent years. However, there is still a lack of methods that can improve the interlaminar and damping properties of carbon fiber reinforced composites at the same time. Based on the existed research, interleaving flexible interlayers (thermoplastic polymer membranes or plant fiber layers) or hybridizing nanoparticles could not only improve the interlaminar properties, but also influence the damping properties. Therefore, the interlaminar hybridization method is used in this thesis to interleave nanoparticles, thermoplastic polymer, nano-fibrous membranes and plant fibers to enhance the interlaminar and damping properties of carbon fiber reinforced composites. For the used thermoplastic polymer, polysulfone is selected to fabricate the thermoplastic interleaves owing to the good miscibility with epoxy. Besides, to well maintain the mechanical properties of the hybrid composites, plant fiber fabrics with better mechanical properties are selected. For the used nanoparticles, cellulose nanocrystals which originate from plants are selected in this thesis. Tongji University Doctor of Engineering Abstract IV Firstly, the effect of cellulose nanocrystals (CNC) and polysulfone (PSF) on the mechanical properties and fracture toughness of epoxy resin are investigated. The CNCs are successfully extracted from microcrystalline cellulose by acid hydrolysis. The extracted CNCs are mixed with epoxy to investigate the effect of different CNC contents on the performance of epoxy matrix. Results show that the homogeneous dispersion of CNCs in the epoxy is the key factor to improve the mechanical properties and fracture toughness of epoxy. The toughening effect of thermoplastic PSF resin is obvious in the epoxy resin. During the curing process, the reaction induced phase separation will occur in the PSF/epoxy blend resin. The phase separation mechanism is closely related to the content of PSF in the PSF/epoxy blend resin. The reinforcing and toughening mechanism of CNC and PSF on the epoxy are revealed by morphological observation and other characterization methods. The mechanical properties and fracture toughness of epoxy can be effectively enhanced after hybridized with CNC and PSF, which provides basic raw materials for the fabrication of interleaves in interlaminar hybridization to improve the interlaminar and damping properties of carbon fiber reinforced composites. Then, based on the above experimental results, the PSF, PSF/CNC nano-fibrous membranes with a certain mass fraction are fabricated by electrospinning technique and interleaved between the interlayers in the unidirectional carbon fiber reinforced epoxy composites. The interlaminar fracture toughness, damping properties and other properties of these interleaved composite laminates are investigated by interlaminar fracture toughness test, vibration damping test and other mechanical tests. Results show that interleaving CNC/PSF nano-fibrous membranes in the carbon fiber reinforced composites effectively enhances the interlaminar fracture toughness and damping properties of carbon fiber reinforced composites. The in-plane mechanical properties are however not affected too much. Based on the obtained test results and microstructure morphological observation, the interlaminar toughening and damping modification mechanism are revealed. Subsequently, the effect of flax fiber hybridization on the interlaminar fracture toughness and damping properties of carbon fiber reinforced composites are investigated. Results show that the interlaminar fracture toughness of carbon fiber reinforced composites is improved greatly after hybridized with flax fiber. Flax fiber surface treatment can further improve the interlaminar properties of the composite laminates. The damping properties of hybrid fiber reinforced composites are greatly Tongji University Doctor of Engineering Abstract V influenced by the stacking sequence of flax fibers. When the flax fibers are at the outmost layers, the damping properties are enhanced significantly compared to carbon fiber reinforced composites. Based on the obtained test results and microstructure morphological observation, the interlaminar toughening and damping enhancement mechanism are revealed, which are related to the multi-layered and hollow microstructure of flax fibers. Lastly, based on the experimental results, the finite element numerical simulation method is used to investigate the interlaminar fracture behavior and vibration process of carbon fiber reinforced epoxy resin hybrid composites from the perspective of calculation. Based on the traditional bilinear cohesive model, a trilinear cohesive model including fiber bridging effect is established to describe the interlaminar fracture behavior of unidirectional fiber reinforced composites. Finite element modal analysis is used to investigate the natural frequency and mode of vibration of unidirectional fiber reinforced composites. Results show that compared to the experimental results, the cohesive model used in this thesis can effectively predict the interlaminar crack propagation and vibration modal characteristics of unidirectional fiber reinforced composites, which provides calculation methods for the optimization design of the interlaminar hybrid composite materials. Conclusively, a new method that can improve the interlaminar and damping properties of carbon fiber reinforced composites simultaneously is introduced in this thesis. The problems of relatively poor interlamianr and damping properties of unidirectional carbon fiber reinforced composites are solved by interlaminar hybridization with electrospun nano-fibrous membranes and plant fibers. The interlaminar toughening and damping enhancement mechanisms of CNC, PSF, nano-fibrous membranes and flax fibers on the carbon fiber reinforced composites are also revealed. On the basis of aforementioned experimental results, the finite element simulation and calculation methods provided to lay the foundation of interlaminar toughening and damping optimization of the carbon fiber reinforced composites.

《赫拉克勒斯：神话与传承》是一场跨学科的展览，其同时采用两条叙事线索来重述古代神话赫拉克勒斯的十二试炼，并探讨了自后文艺复兴时期至今赫拉克勒斯在科学、技术和艺术领域的影响与应用。 此次展览是周泽荣博物馆致力于“接受研究”系列展览中的第二场展览。第一场展览《动物之神：古典与分类》是关于荷马史诗《特洛伊战》和《奥德赛》。展览中介绍了林奈的生物分类和命名系统，突出了拉丁神话学家文本在名称应用中的作用，其往往没有考虑到被命名动物的物理属性。然而，对于使用‘赫拉克勒斯’ 这个名称的时候，最重要的是考虑到动物、地点或发明物的身体特征，以便将它们与赫拉克勒斯的特征联系起来。此次陈列品包括古代雅典和后文艺复兴时期的艺术作，以及在我们周围世界中应用了赫拉克勒斯及其同伴或对手的名称的动物、植物和物品。

Powder bed fusion additive manufacturing has been applied to the fabrication of functionally graded materials. A new design that allows the material composition to change along the direction perpendicular to the powder spreading has been reported in the literature. Based on this design, this work examines the quality of the graded spread powder layer with two powders, which have a large difference of density. The results reveal that during the spreading of graded powders, the volume of particles on the heavy powder side is deposited less than that on the light powder side, indicating that heavy particles diffuse to the light powder side. This diffusion is affected by the spreading speed, but not much by the layer gap. Large spreading speed causes more significant deviation. The results also show that particle size affects diffusion, indicating that decreasing the particle size of the heavy powder may be a solution to reduce diffusion. [Figure not available: see fulltext.] Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Resources & Recycling