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11.
Energy storage is an important adjustment method to improve the economy and reliability of a power system. Due to the complexity of the coupling relationship of elements such as the power source, load, and energy storage in the microgrid, there are problems of insufficient performance in terms of economic operation and efficient dispatching. In view of this, this paper proposes an energy storage configuration optimization model based on reinforcement learning and battery state of health assessment. Firstly, a quantitative assessment of battery health life loss based on deep learning was performed. Secondly, on the basis of considering comprehensive energy complementarity, a two-layer optimal configuration model was designed to optimize the capacity configuration and dispatch operation. Finally, the feasibility of the proposed method in microgrid energy storage planning and operation was verified by experimentation. By integrating reinforcement learning and traditional optimization methods, the proposed method did not rely on the accurate prediction of the power supply and load and can make decisions based only on the real-time information of the microgrid. In this paper, the advantages and disadvantages of the proposed method and existing methods were analyzed, and the results show that the proposed method can effectively improve the performance of dynamic planning for energy storage in microgrids.  相似文献   
12.
(1) Background: Due to human activities, greenhouse gas (GHG) concentrations in the atmosphere are constantly rising, causing the greenhouse effect. Among GHGs, carbon dioxide (CO2) is responsible for about two-thirds of the total energy imbalance which is the origin of the increase in the Earth’s temperature. (2) Methods: In this field, we describe the development of periodic mesoporous organosilica nanoparticles (PMO NPs) used to capture and store CO2 present in the atmosphere. Several types of PMO NP (bis(triethoxysilyl)ethane (BTEE) as matrix, co-condensed with trialkoxysilylated aminopyridine (py) and trialkoxysilylated bipyridine (Etbipy and iPrbipy)) were synthesized by means of the sol-gel procedure, then characterized with different techniques (DLS, TEM, FTIR, BET). A systematic evaluation of CO2 adsorption was carried out at 298 K and 273 K, at low pressure. (3) Results: The best values of CO2 adsorption were obtained with 6% bipyridine: 1.045 mmol·g−1 at 298 K and 2.26 mmol·g−1 at 273 K. (4) Conclusions: The synthetized BTEE/aminopyridine or bipyridine PMO NPs showed significant results and could be promising for carbon capture and storage (CCS) application.  相似文献   
13.
This study presents the construction and dielectric properties investigation of atomic-layer-deposition Al2O3/TiO2/HfO2 dielectric-film-based metal–insulator–metal (MIM) capacitors. The influence of the dielectric layer material and thickness on the performance of MIM capacitors are also systematically investigated. The morphology and surface roughness of dielectric films for different materials and thicknesses are analyzed via atomic force microscopy (AFM). Among them, the 25 nm Al2O3-based dielectric capacitor exhibits superior comprehensive electrical performance, including a high capacitance density of 7.89 fF·µm−2, desirable breakdown voltage and leakage current of about 12 V and 1.4 × 10−10 A·cm−2, and quadratic voltage coefficient of 303.6 ppm·V−2. Simultaneously, the fabricated capacitor indicates desirable stability in terms of frequency and bias voltage (at 1 MHz), with the corresponding slight capacitance density variation of about 0.52 fF·µm−2 and 0.25 fF·µm−2. Furthermore, the mechanism of the variation in capacitance density and leakage current might be attributed to the Poole–Frenkel emission and charge-trapping effect of the high-k materials. All these results indicate potential applications in integrated passive devices.  相似文献   
14.
根据全息透镜的工作原理,利用光线追迹法对其聚焦特性进行了理论分析。使用标量衍射法分析了全息透镜的衍射效率,讨论了不同的光栅槽型对其衍射效率的影响。对分析过程中所涉及到的有关近似处理方法的使用和影响进行了说明,讨论了全息透镜用作取样光栅的优点。  相似文献   
15.
16.
低温液体无损贮存压力升高的实验与计算   总被引:1,自引:0,他引:1  
谢高峰  陈叔平  袁斌  李秋英 《低温与超导》2006,34(6):437-439,442
准确、简单地预测低温液体无损贮存时的压力升高具有重要的实用价值。对一低温容器利用液氮为介质进行了多次无损贮存实验,利用多元线性回归方法对实验数据进行分析和检验。分析表明无损贮存时间、初始充满率对压力升高的影响较大,而环境温度的影响可以忽略,并拟合出了压力升高的计算公式。计算结果和实验结果在很大范围内能够较好地吻合。该种计算方法在预测低温液体无损贮存压力升高时有较高的准确性与可靠性。  相似文献   
17.
We present the study of angular selectivity for holographic multiplexing based on random phase encoding by a ground glass. The rotational selectivity of the volume hologram is calculated theoretically and coincides with the experimental measurement. By controlling the parameters including rotational center, effective numerical aperture of both volume hologram and the ground glass, we can obtain different rotational selectivity applied to random phase encoding in volume holographic storage.  相似文献   
18.
Summary The free convection in the melt during the crystal growth of small-gap semiconductors, and its influence on the electrical properties are discussed. Dimensionaless parameters of the fluid flow, electrical properties of PbTe, Pb1−x Sn x Te and Hg1−x Cd x Te single crystals, grown by vertical Bridgman technique at very low velocity, and some structures, found in these materials, support the presence of free convection.  相似文献   
19.
魏振乾  费浩生 《光学学报》1995,15(8):082-1087
研究了偶氮基染料掺杂薄膜MO-PVA和EO-PVA的双光子存储特性。在对薄膜用Ar^+激光作预激发下实现了He-Ne激光的红光存储。获得了实时和短时存储照片。光电记录存储曲线,分析了双光四能级系统的存储机制。实现确定了最佳预激发功率约为0.28W/cm^2,最小He-Ne光可存储功率密度低于0.2W/cm^2。  相似文献   
20.
汪国平  郭履容 《光学学报》1995,15(11):534-1537
通过化学反应,在三醋酸纤维素睛基的正反两面同时生成具有感光活性的光敏层的方法,获得了一种具有叠层光敏性的全息记录软片:重铬酸盐-三醋酸纤维素酯。由该软片记录的叠层体积全息光栅,具有迄今为止,最高的一级实验衍射效率(54%)。  相似文献   
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