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991.
The ever-increasing travel demand has brought great challenges to the organization, operation, and management of the subway system. An accurate estimation of passenger flow distribution can help subway operators design corresponding operation plans and strategies scientifically. Although some literature has studied the problem of passenger flow distribution by analyzing the passengers’ path choice behaviors based on AFC (automated fare collection) data, few studies focus on the passenger flow distribution while considering the passenger–train matching probability, which is the key problem of passenger flow distribution. Specifically, the existing methods have not been applied to practical large-scale subway networks due to the computational complexity. To fill this research gap, this paper analyzes the relationship between passenger travel behavior and train operation in the space and time dimension and formulates the passenger–train matching probability by using multi-source data including AFC, train timetables, and network topology. Then, a reverse derivation method, which can reduce the scale of possible train combinations for passengers, is proposed to improve the computational efficiency. Simultaneously, an estimation method of passenger flow distribution is presented based on the passenger–train matching probability. Finally, two sets of experiments, including an accuracy verification experiment based on synthetic data and a comparison experiment based on real data from the Beijing subway, are conducted to verify the effectiveness of the proposed method. The calculation results show that the proposed method has a good accuracy and computational efficiency for a large-scale subway network. 相似文献
992.
Persistent luminescence materials (PLMs) are a class of unique lumi-nescent materials that can remain luminescent for a few milliseconds to days without constan... 相似文献
993.
爆轰合成超细金刚石机理探讨 总被引:3,自引:2,他引:1
就爆轰合成超细金刚石的机理进行探讨:1.传统的碳相图已不能作为爆轰合成过程的依据;2.由于存在等离子体-晶体的直接相变,整个过程可能有几种相变作用共存;3.爆炸容器中的介质对产物有重要的影响。最后,提出了对整个问题进行研究所应遵循的规律。 相似文献
994.
Bo-Sheng Zhang Ying-Hui Yang Fan Wang Xue-Ya Gou Xi-Cun Wang Yong-Min Liang Yuke Li Zheng-Jun Quan 《中国化学》2021,(6):1573-1579
Main observation and conclusion
This paper describes the first case of a reductive coupling reaction with indene,a non-heteroatom olefin used as a reducing agen... 相似文献
995.
几种高性能纤维束的冲击动力学性能实验研究 总被引:6,自引:0,他引:6
利用直拉式Hopkinson装置研究了碳纤维、无碱E玻璃纤维、Kevlar 4 9/96 4 /96 4c、Twaron2 0 0 0、DyneemaSk6 6等纤维的动态拉伸性能。与准静态加载条件下相比 ,纤维束的拉伸强度基本与应变速率无关(玻璃纤维除外 ) ,而纤维束的弹性模量和失效应变随应变率的升高而明显变大。从高分子物理以及两种无机纤维的内部微观结构特征对纤维的力学性能与加载速率的关系进行了初步的物理阐释。讨论了实验数据的发散原因。 相似文献
996.
Wei Ge Chao Liu Yatao Xu Jiayao Zhang Weili Si Wenjun Wang Changjin Ou Xiaochen Dong 《Chemical science》2022,13(32):9401
Organic charge-transfer complexes (CTCs) can function as versatile second near-infrared (NIR-II) theranostic platforms to tackle complicated solid tumors, while the structure–property relationship is still an unanswered problem. To uncover the effect of molecular stacking modes on photophysical and biochemical properties, herein, five ferrocene derivatives were synthesized as electron donors and co-assembled with electron-deficient F4TCNQ to form the corresponding CTCs. The crystalline and photophysical results showed that only herringbone-aligned CTCs (named anion-radical salts, ARS NPs) possess good NIR-II absorption ability and a photothermal effect for short π–π distances (<3.24 Å) and strong π-electron delocalization in the 1D F4TCNQ anion chain. More importantly, the ARS NPs simultaneously possess ·OH generation and thiol (Cys, GSH) depletion abilities to perturb cellular redox homeostasis for ROS/LPO accumulation and enhanced ferroptosis. In vitro experiments, FcNEt-F4 NPs, and typical ARS NPs, show outstanding antitumor efficiency for the synergistic effect of NIR-II photothermal therapy and ferroptosis, which provides a new paradigm to develop versatile CTCs for anti-tumor application.Based on crystal engineering of charge transfer complexes (CTCs), ferrocene-based CTCs, with Fenton-catalyzing, biothiol-responsive and NIR-II photothermal abilities, were controllably developed and the structure–property relationship was revealed. 相似文献
997.
资源有限网络计划启发式方法的评价(中):启发式方法的综合比较和评价 总被引:1,自引:0,他引:1
通过设计评价启发式方法优劣效果的度量指标——工期比率、比率和及差值率,利用随机活动网络发生器产生的50 个网络计划,对最常用的31 种资源有限网络计划的启发式方法的总体效果进行了比较、分析、评价和排序,便于人们在使用启发式方法之前,就可以预知该方法的大致效果,估计可能引起的偏差,在满足实际需要的前提下,选择合适的启发式方法。 相似文献
998.
Li Yu‐yi Teng Bing Zhong De‐gao Wang Chao Zhang Shi‐ming Yang Li‐ting Yu Meng‐hua Quan Xin‐yu Chen Chen Wu Yun‐long 《Crystal Research and Technology》2014,49(12):939-942
A new kind of 5 at% Yb‐doped Lu0.5Y0.5PO4 crystals were firstly grown by spontaneously nucleated high‐temperature solution method using lead pyrophosphate (Pb2P2O7) as the solvent. The X‐ray powder diffraction (XRPD) patterns recorded at room temperature showed the crystals possessed tetragonal xenotime structure. The polarized absorption spectra and the fluorescence spectra of Yb:LuxY1‐xPO4 were measured at room temperature, respectively. The results show that Yb:LuxY1‐xPO4 mixed crystal will be a promising laser material if the crystal size and quality is further improved. 相似文献
999.
Lipeng Zhou Beibei Dong Si Tang Hong Ma Chen Chen Xiaomei Yang Jie Xu 《Journal of Energy Chemistry》2013,22(4):659-664
Sulfonated carbon as a strong and stable solid acid catalyst exhibited excellent catalytic performance in various acid-catalyzed reactions. Here, sulfonated carbon, as catalyst for oxidation reaction, was prepared via the carbonization of starch followed by sulfonation with concentrated sulfuric acid. N2 physisorption, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray fluorescence and acid-base titration were used to characterize the obtained materials. The catalytic activity of sulfonated carbon was studied in the oxidation of aldehydes to carboxylic acids using 30 wt% H2O2 as oxidant. This oxidation protocol works well for various aldehydes including aromatic and aliphatic aldehydes. The sulfonated carbon can be recycled for three times without obvious loss of activity. 相似文献
1000.
Zhiming Zhang Shuang Yao Enbo Wang Quan Shi Hong Zhang 《Journal of Cluster Science》2008,19(3):521-530
Two new tungstogermanates K2Na10[Cu4(GeW9O34)2] · 15.5H2O (1) and K4Na6[Cu3.5W0.5(H2O)2(GeW9O34)2] · 17H2O (2) have been obtained by the conventional aqueous solution methods and characterized by IR, element analysis, electrochemistry
and single-crystal X-ray analysis. Compound 1 is composed of the [Cu4(GeW9O34)2]12− anions linked by two equivalent bonds of Cu–O–W, representing the first one-dimensional chain-like structure based on sandwich-type
polyoxometalates by direct condensation to form oxo-bridged arrays of clusters. Compound 2 is a sandwich structure, consisting of two trivacant [GeW9O34]10− units linked by a [Cu3.5W0.5(H2O)2] cluster, and the anions are linked by the K+ and Na+ to form a three-dimensional structure.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献