检索结果-南通市图书馆

考虑分时电价和充电利用率特征的大型电动汽车充电站负荷短期预测方法

在线全文

学校读者我要写书评

暂无评论

南方电网技术 2024年第5期18卷 75-84页

作者：王长春王果赵倩宇王守相兰州交通大学自动化与电气工程学院兰州730070 天津大学电气自动化与信息工程学院天津300072

考虑分时电价和充电利用率特征对电动汽车充电站负荷的影响,提出了融合长短记忆网络和支持向量回归(long short-term memory-support vector regression,LSTM-SVR)的大型电动汽车充电站负荷短期预测方法。首先,建立了分时电价、充电利... 详细信息

考虑分时电价和充电利用率特征对电动汽车充电站负荷的影响,提出了融合长短记忆网络和支持向量回归(long short-term memory-support vector regression,LSTM-SVR)的大型电动汽车充电站负荷短期预测方法。首先,建立了分时电价、充电利用率、气象信息等影响充电负荷的因素以及历史充电负荷功率数据作为输入的特征矩阵。其次,运用自适应噪声完备经验模态分解(complete ensemble empirical mode decomposition with adaptive noise,CEEMDAN)方法将包含分时电价和充电利用率的特征矩阵序列进行分解,扩充了数据多样性,并采用组合相关系数方法实现了数据降维和特征选择。然后采用北方苍鹰优化(northern goshawk optimization,NGO)算法分别优化LSTM和SVR的超参数,求解权重系数并构建融合LSTM-SVR模型。最后采用某城市一座大型充电站数据进行验证,对比实验表明,考虑分时电价和充电利用率特征可有效提高电动汽车充电站负荷预测精度8%以上,同时采用所提出的融合LSTM-SVR预测方法能使预测精度进一步提高。

关键词：短期负荷预测电动汽车充电站充电利用率分时电价长短期记忆网络支持向量回归自适应噪声完备经验模态分解

同方期刊数据库

在线全文

学校读者我要写书评

暂无评论

提高电动汽车接纳能力的配电网动态重构方法

供用电 2024年第4期41卷 89-95页

作者：石立国李延真胡洋王者龙陈雷王长春国网山东省电力公司青岛供电公司山东青岛266000 天津相和电气科技有限公司天津300000

为提高配电网对电动汽车的接纳能力,提出一种考虑光伏出力、负荷及电动汽车充电功率不确定性的配电网动态重构方法。首先通过引入仿射数,对光伏出力、负荷及电动汽车充电功率不确定性进行描述。然后,以最大化电动汽车接纳能力为目标,建... 详细信息

为提高配电网对电动汽车的接纳能力,提出一种考虑光伏出力、负荷及电动汽车充电功率不确定性的配电网动态重构方法。首先通过引入仿射数,对光伏出力、负荷及电动汽车充电功率不确定性进行描述。然后,以最大化电动汽车接纳能力为目标,建立配电网动态重构模型,并通过改进郊狼算法进行求解,得到一天内24 h静态重构结果,并对重构结果相同的时段进行合并。最后,提出了基于欧氏距离的动态重构时段划分方法,将重构时段进行进一步合并,得到最终的动态重构时段。通过86节点配电网对所提重构方法进行仿真分析,结果表明,所提方法能够将电动汽车接纳能力提升21.16%,同时能够减少重构时段,降低开关的动作次数。

关键词：电动汽车接纳能力不确定性动态重构郊狼算法欧氏距离

离子液体的制备及在甲醇-碳酸二甲酯共沸物分离中的应用现状

在线全文

学校读者我要写书评

暂无评论

化工新型材料 2024年第3期52卷 47-51页

作者：于鑫宇王常春闫博文毕胜丛玉凤辽宁石油化工大学石油化工学院抚顺113001

碳酸二乙酯(DEC)生产过程中,甲醇(MeOH)与碳酸二甲酯(DMC)形成二元共沸物,传统有机溶剂萃取精馏分离MeOH-DMC共沸物存在污染环境、萃取效率低及溶剂回收难等难题。离子液体作为一种新型溶剂,因其绿色环保、萃取效率高及可循环再利用等优... 详细信息

碳酸二乙酯(DEC)生产过程中,甲醇(MeOH)与碳酸二甲酯(DMC)形成二元共沸物,传统有机溶剂萃取精馏分离MeOH-DMC共沸物存在污染环境、萃取效率低及溶剂回收难等难题。离子液体作为一种新型溶剂,因其绿色环保、萃取效率高及可循环再利用等优势,在化工领域中展现出广泛的应用前景。简述了离子液体的种类及其性质,分析了离子液体典型的五种合成方法存在的优缺点,重点讨论了离子液体对MeOH-DMC共沸物的研究进展及其分离机理,指出了目前离子液体应用于MeOH-DMC共沸物分离中存在的问题,最后对离子液体的未来发展方向提出了展望。

关键词：碳酸二甲酯离子液体萃取精馏共沸物

Dual-sided symmetric crystalline orientation of covalent organic framework membranes for unidirectional anhydrous proton conduction

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2022年第12期65卷 2548-2557页

作者： Shujing Liu Zheng Lin changchun wang Jia Guo State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular Science and Lab of Advanced MaterialsFudan UniversityShanghai200438China

Two-dimensional covalent organic frameworks(2D COFs)have sparkled wide-ranging research to explore proton-conducting ***,the powder-pressed pellets or continuous membranes of 2D COFs are composed of randomly arranged crystallites,which are undesirable for proton transport via a shortcut *** report a controlled strategy for preparing a conformably oriented free-standing COF membrane to address the critical challenge.A monofunctional aldehyde precursor is used as a modulator to enhance reversible association and optimize growth orientation in an interfacial polymerization *** preferred face-on alignment is achieved throughout the membrane from its flat side to the nanoflake-standing side and,in turn,generates the unidirectional pore channels for accommodating 1,2,4-triazole as proton *** composite merges distinctive features including orientation,crystallinity,porosity,and mechanical strength into one system,exhibiting ultrafast and stable anhydrous proton conduction at high operating temperatures with low activation *** findings offer an innovative strategy for the oriented crystallization of free-standing COF membranes for energy conversion applications.

关键词： covalent organic frameworks oriented crystallization anhydrous proton conduction interfacial polymerization membranes

Geochemistry and Genesis of the Sodium-Charnockitic Gneisses, Eastern Hebei Province, China

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 1992年第3期66卷 239-258页

作者： wang Anjian changchun University of Earth Sciences, changchun, Jilin changchun University of Earth Sciences Changchun Jilin

High in sodium and low in potassium (Na_2O/ K_2O>1), the charnockitic gneiss series in theSantunying- Taipingzhai area, eastern Hebei province, consists of hypersthene- quartz- diorite,hypersthene-granodiorite and hypersthene-plagioclase-granite. Geological, petrological and large ion lithophileelement(LILE), high field strength element (HFSE) and REE geochemical studies suggest that themedium-coarse-grained hypersthene-granodiorite is the product of crystallization of anatectic magmas of thesame composition. Under granulite facies conditions, the equilibrium crystallization differentiation of themagmas yielded the early crystallization phase-high-SiO_2, LILE-depleted, low-∑REE, positive Eu anomalyand REE- saturated hypersthene- plagioclase- granite. The residual phase, coarse- grained to pegmatitichypersthene- granodiorite, is marked by low SiO_2, LILE-enrichment, high ∑REE and *** rocks and hypersthene-quartz-diorite enclaves constitute the sodium-charnockitic gneiss series in easternHebei province. Model calculation for trace elements in the granitoids was applied. On the basis of a systematicgeological study, the equation for calculation was chosen, the source magma was determined and the partitioncoefficients were obtained. The resulting curves are entirely consistent with those observed in the patterns of ac-tual rocks. The study indicates that whole-rock REE patterns can not be used directly in the comparison of thesources and genesis of granitoids.

关键词： sodium-charnockitic gneisses geochemistry genesis eastern Hebei province

Distributed cooperative task planning algorithm for multiple satellites in delayed communication environment

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2016年第3期27卷 619-633页

作者： Chong wang Jinhui Tang Xiaohang Cheng Yingchen Liu changchun wang National Key Laboratory of Airspace Technology Beijing 100085China

Multiple earth observing satellites need to communicate with each other to observe plenty of targets on the Earth together. The factors, such as external interference, result in satellite information interaction delays, which is unable to ensure the integrity and timeliness of the information on decision making for satellites. And the optimization of the planning result is affected. Therefore, the effect of communication delay is considered during the multi-satel ite coordinating process. For this problem, firstly, a distributed cooperative optimization problem for multiple satellites in the delayed communication environment is formulized. Secondly, based on both the analysis of the temporal sequence of tasks in a single satellite and the dynamically decoupled characteristics of the multi-satellite system, the environment information of multi-satellite distributed cooperative optimization is constructed on the basis of the directed acyclic graph（DAG）. Then, both a cooperative optimization decision making framework and a model are built according to the decentralized partial observable Markov decision process（DEC-POMDP）. After that, a satellite coordinating strategy aimed at different conditions of communication delay is mainly analyzed, and a unified processing strategy on communication delay is designed. An approximate cooperative optimization algorithm based on simulated annealing is proposed. Finally, the effectiveness and robustness of the method presented in this paper are verified via the simulation.

关键词： Earth observing satellite(EOS) distributed coo-perative task planning delayed communication decentralized partial observable Markov decision process(DEC-POMDP) simulated annealing

Synthesis of mordenite by solvent-free method and its application in the dimethyl ether carbonylation reaction

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2024年第2期66卷 216-223页

作者： Yinghui Liu Shaoduo Liu Xiaosheng wang Hongjing wang Ranjia Li changchun Yu Chunming Xu Yuxiang Liu Zhengqiu Xie Yongqiang wang Pan Tang State Key Laboratory of Heavy Oil Processing College of New Energy and MaterialsChina University of Petroleum-BeijingBeijing 102249China Synfuels China Technology Co. LtdBeijing 101400China College of Chemical Engineering Qingdao University of Science&TechnologyQingdao 266042China Yueyang Jucheng Chemical Co. LtdYueyang 414009China

Mordenite with different Si/Al ratios were synthesized by solvent-free method and used for dimethyl ether(DME)carbonylation *** influence of Si/Al ratio in the feedstock on the structure,porosity and acid sites were systematically *** characterization results showed that with the increase of Si/Al ratio in the feedstock,part of silicon species fail to enter the skeleton and the specific surface area and pore volume of the samples *** amount of weak acid and medium strong acid decreased alongside with the increasing Si/Al ratio,and the amount of strong acid slightly *** Al atoms preferentially enter the strong acid sites in the 8 member ring(MR)channel during the crystallization *** high Si/Al ratio sample had more acid sites located in the 8 MR channel,leading to more active sites for carbonylation reaction and higher catalytic *** increasing the Si/Al ratio was beneficial for the improvement of carbonylation reaction activity over the mordenite(MOR)catalyst.

关键词： Carbonylation Dimethyl ether Solvent-free Zeolite Synthesis Catalysis

Effect of the partial substitution of Mg by Al on the crystal structure and hydrogenation behavior of La_2Mg_(17)

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2007年第4期26卷 347-351页

作者： ZHANG Qing＇ an wang changchun SI Tingzhi School of Materials Science and Engineering Anhui University of Technology Maanshan 243002 China

The effect of the partial substitution of Mg by A1 on the crystal structure of La2Mg17 has been investigated. It was found that the LaEMgl7 phase disappears after the partial substitution of Mg by Al. The LaE（***0.1）17 alloy contains La（Mg,AI）12 and La（Mg,Al）2. Further increasing the Al content, the La2（Mg0.8Al0.2）17 alloy consists of La（Mg,Al）12, La（Mg,Al）2, and Mg. The La（Mg0.93Al0.07）12 phase in the La2（Mg0.9Al0.1）17 alloy crystallizes with the ThMn12-type structure in space group 14/mmm （No. 139）. The lattice parameters were determined to be a = 1.03246（7） nm and c = 0.59410（6） nm. In the ThMn12-type structure, AI atoms occupy 8f site but the A1 content is limited. Moreover, the hydrogenation character- istics have also been compared. La2Mgl7 decomposes into LaH3 and MgH2 under hydrogen, but the La（Mgo.93Alo.o7）12 phase can be hydrogenated into LaH3, MgH2, and La3Al11 at 473 K.

关键词： intermetallic compound crystal structure hydrogenation characteristic X-ray diffraction

Portable fluorescence instrument for detecting membrane integrity in membrane bioreactor (MBR)

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2024年第2期18卷 121-131页

作者： Yang Yu changchun Xin Yuxiang Liu Fei Gao Lei Zhang Hui Jia Jie wang State Key Laboratory of Separation Membranes and Membrane Processes Tiangong UniversityTianjin 300387China School of Environmental Science and Engineering Tiangong UniversityTianjin 300387China School of Environmental Science and Engineering Tianjin UniversityTianjin 300072China Shenyang Academy of Environmental Sciences Shenyang 110167China Cangzhou Institute of Tiangong University Tiangong UniversityCangzhou 061000China

This study proposed the design, fabrication, and assembly of membrane integrity detection instruments in membrane bioreactors (MBR) based on fluorescence spectroscopy. Based on the PARAFAC model, we found that the peak at 280/335 nm strengthened after membrane breakage. The peak at 340/430 nm reflected the sludge concentration in the MBR and reduced the influence of internal filtration effects on detection. Therefore, we determined that the dual-LED light source excitation detection system can detect tryptophan-like substances at 280 nm (T-peak) and humic acid at 340 nm (C-peak). T-peak was identified as the core index indicating membrane integrity. Moreover, the C-peak is the reference indicator factor for a sensitive response to changes in the sludge concentration. The portable fluorescence instrument exhibited high sensitivity and good feedback accuracy compared to particle counting and turbidity detection, where the log reduction value was greater than 3.5. This overcomes the disadvantage of false alarms in particle counters and is not affected by the position of the pump system. This portable instrument provides a flexible and highly sensitive method for the assessment of industrial membrane integrity.

关键词： Membrane integrity Fluorescence spectrum Portable instrument Membrane bioreactor