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基于货量预测与优化调度的电商物流网络问题研究

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科技创新与生产力 2024年第10期45卷 22-27页

作者：柴和平沈雪季英杰马和平新疆理工学院新疆阿克苏843100

本文指出电商物流网络是由物流场地和运输线路组成的,在用户下单量受到促销活动和突发事件等因素影响时,可能导致包裹数量变化。为了提高效率和降低运营成本,管理者需要预测各物流场地及线路的货量并合理安排运输、分拣等计划。通过分... 详细信息

本文指出电商物流网络是由物流场地和运输线路组成的,在用户下单量受到促销活动和突发事件等因素影响时,可能导致包裹数量变化。为了提高效率和降低运营成本,管理者需要预测各物流场地及线路的货量并合理安排运输、分拣等计划。通过分析数据,本文假设处理能力和运输能力上限均为其历史货量最大值,然后对应急调运与物流网络结构优化问题进行了研究,建立了物流预测模型、多目标优化模型以及综合评价模型,此问题的研究为应急调运和物流网络结构的优化提供了有效手段。

关键词：电商物流网络多目标规划 ARIMA-LSTM 模拟退火算法熵权法

维普期刊数据库博看期刊

Investigation of vortex arms in electron vortices by counter-rotating elliptically polarized attosecond laser pulses

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Communications in Theoretical Physics 2022年第1期74卷 84-91页

作者： Zhuo Wang Qi Zhen Yue Sun Jia-He Chen xue-shen Liu Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China School of Civil Engineering Changchun Institute of TechnologyChangchun 130012China

We theoretically investigate the vortex patterns in photoelectron momentum distributions of He^(+)driven by counter-rotating elliptically polarized,time delayed attosecond laser pulses by numerically solving the two-dimensional time-dependent Schrodinger *** is found that the number of vortex arms is extremely sensitive to the ellipticity and wavelength of counterrotating elliptically polarized laser pulses,which is illustrated by the attosecond perturbation ionization *** addition,the effect of different time delays between two pulses on the interference patterns is also investigated and the corresponding physical mechanism is *** the wavelength,ellipticity and time delay have a significant effect on the vortex interference patterns,this may be a new method for laser field detection.

关键词： vortex arms photoelectron momentum distributions elliptically polarized laser pulses

Semi-integer harmonic generation from an argon atom by bichromatic counter-rotating circularly polarized laser field

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Chinese Physics B 2020年第5期29卷 219-224页

作者： Tong Qi Xiao-Xin Huo Jun Zhang xue-shen Liu Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China

We theoretically investigated the properties of the high-order harmonic generation from an argon atom by bichromatic counter-rotating circularly polarized(BCCP)laser *** harmonic emission processes have been illustrated by numerically solving the two-dimensional time-dependent Schr¨odinger equation of an atom in intense laser *** is found that with the decrease of the right-circularly polarized laser wavelength,the harmonic spectra are gradually splitting and the harmonic orders move towards the higher ***,the integer and semi-integer harmonic emission will be generated when the frequency ratios of right-and left-circularly polarized lasers are *** emission mechanism of the semi-integer-order harmonics has been investigated by using the rules of photon absorption and emission.

关键词： high-order harmonic generation semi-integer-order photon absorption and emission bichromatic counter-rotating circularly polarized laser field

Implementation of CMA-GFS 3D-Var System on the Yin-Yang Grid

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Journal of Tropical Meteorology 2021年第4期27卷 346-354页

作者： ZHUANG Zhao-rong xue Ji-shan shen xue-shun LI Xing-liang CMA Earth System Modeling and Prediction Centre Beijing 100081 China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081 China

The global three-dimensional variational(3D-Var)data assimilation is implemented on a new quasi-uniform overset(Yin-Yang)grid on *** a quasi-uniform spherical grid,it covers the sphere by overlapping two perpendicularly oriented grid components which is nothing but low latitude region of the usual latitude-longitude *** on this characteristic of the Yin-Yang grid,it enables us to implement the regional 3D-Var system efficiently and accurately on the Yin or Yang component grid,*** global analysis could update directly from the regional analysis since they have the same configurations like the precondition of eigenvalue decomposition for vertical direction,recursive filtering for horizontal direction,minimization method and observation operator and so ***,the balance equation and vector wind are needed to be paid more attention on the Yin grid analysis due to its coordinate *** to spread the observation information near the boundary of Yin and Yang grid is a key to the 3D-Var *** double the horizontal correlation length distance in the overset boundary of Yin and Yang grid has successfully solved the *** results show that the analysis on the Yin-Yang grid is reasonable and similar to the result on the latitude-longitude(LAT-LON)*** paper provides a promising strategy for the development of a 3D-Var global system for overset grids.

关键词： Yin-Yang grid latitude-longitude grid CMA-GFS regional 3D-Var global 3D-Var

Helicity of harmonic generation and attosecond polarization with bichromatic circularly polarized laser fields

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Chinese Physics B 2019年第10期28卷 321-326页

作者： Jun Zhang Tong Qi xue-Fei Pan Jing Guo Kai-Guang Zhu xue-shen Liu College of Instrumentation and Electrical Engineering Jilin UniversityChangchun 130026China Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China

We theoretically investigate the high-order harmonic generation(HHG) of helium atom driven by bichromatic counterrotating circularly polarized laser fields. By changing the intensity ratio of the two driving laser fields, the spectral chirality of the HHG can be controlled. As the intensity ratio increases, the spectral chirality will change from positive-to negativevalue around a large intensity ratio of the two driving fields when the total laser intensity keeps unchanged. However, the sign of the spectral chirality can be changed from positive to negative around a small intensity ratio of the two driving fields when the total laser intensity changes. At this time, we can effectively control the helicity of the harmonic spectrum and the polarization of the resulting attosecond pulses by adjusting the intensity ratio of the two driving laser fields. As the intensity ratio and the total intensity of the driving laser fields increase, the relative intensity of either the left-circularly or right-circularly polarized harmonic can be enhanced. The attosecond pulses can evolve from being elliptical to near linear correspondingly.

关键词： high-order harmonic generation bichromatic circularly polarized laser fields spectral chirality attosecond polarization

Soil Erodibility and Physicochemical Properties of Collapsing Gully Alluvial Fans in Southern China

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Pedosphere 2019年第1期29卷 102-113页

作者： DENG Yusong shen xue XIA Dong CAI Chongfa DING Shuwen WANG Tianwei Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River) of the Ministry of Agriculture College of Resources and Environment Huazhong Agricultural University Forestry College Guangxi University College of Economics and Management Huazhong Agricultural University

In southern China, collapsing gully erosion produces massive deposits of sediment on the plough layer of alluvial fan farmland,leading to reduced nutrients, increased erodibility, and even desertification. The aim of this study was to investigate soil erodibility(the factor K in the Universal Soil Loss Equation, USLE) and physicochemical properties of the alluvial fans of the most severe collapsing gully erosion areas(Hubei, Jiangxi, Fujian, and Guangdong provinces) in southern China. The soils of the collapsing gully alluvial fans had a higher bulk density, but a lower total porosity, saturated water content, and silt and clay fractions than the control(CK) soils from the farmland without desertification. Soil quality gradually decreased from fan edge to fanhead. Significant decreases were found in soil p H, organic matter, cation exchange capacity, and total potassium, nitrogen, and phosphorus, as well as available nitrogen, phosphorus, and potassium, resulting in a gradual decrease in soil nutrients from the fanedge to the fanhead. Soil erodibility was greatest in the fanhead, and soil erodibility K values of the alluvial fans were 53.71%, 66.28%, 67.53%, and 71.68% greater than that in those of the CK soils of Hubei, Jiangxi, Fujian, and Guangdong, respectively, indicating a significant correlation between the soil erodibility K values and physicochemical properties, particularly sand fraction and organic matter content. The results provide new insights into the relationship between soil physicochemical properties and erodibility of alluvial fans, and suggest that improving soil structure might increase soil fertility in the collapsing gully alluvial fan farmland.

关键词： soil erosion soil fertility soil property soil quality soil structure

Occurrence and Characterization of Pale,Soft,Exudative-Like Broiler Muscle Commercially Produced in China

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Journal of Integrative Agriculture 2012年第8期11卷 1384-1390页

作者： ZHU xue-shen XU Xing-lian MIN Hui-hui ZHOU Guang-hong National Center of Meat Quality and Safety Control Nanjing Agricultural UniversityNanjing 210095P.R.China

Pale, soft, exudative-like （PSE-like） broiler muscle is a growing problem for meat industry all over the world. However, limited studies have been made to assess broiler meat quality in China. The aim of this study was to investigate the characteristics and incidence of PSE-like broiler muscle commercially produced in China. A total of 1 274 Pectoralis muscles of Arbor Acre broiler were randomly obtained from the processing line to determine the commercial incidence of PSE-like muscle based on color. Furthermore, broiler Pectoralis muscles selected from the 1 274 muscle samples were classified as PSE-like muscle （L＊〉53, n=33） and normal muscle （L＊〉48 and L＊=53, n=33） to assess meat quality. It was determined that PSE-like muscle had lower muscle pH values, lower water-holding capacity （WHC）, lower sarcoplasmic protein solubility, and lower total protein solubility than the normal muscle did. SDS-PAGE profile also showed that bands of approximate 96 and 24 kDa in sarcoplasmic protein and myofibrillar protein varied between these two groups, suggesting partial denaturation of sarcoplasmic proteins and precipitation on myofillarments. Correlation analysis showed that L＊ values have significant correlation with WHC and protein solubility. Furthermore, the distribution of L＊ values exhibited a normal curve with range varying from 42.70 to 58.37. It was considered that approximately 23.39% of the population was PSE-like muscle. These results suggest that PSE-like meat can represent a significant portion of commercially processed broiler breast meat in China and that the L＊ value measurement could be used to sort broiler meat quality using a cut-off point.

关键词： broiler Pectoralis muscles color water-holding capacity protein solubility

叶酸代谢基因检测在降低胎儿神经管畸形发生率中的应用

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中国妇幼保健 2024年第7期39卷 1325-1328页

作者：李华沈学萍卢绚丽顾惠凤湖州市妇幼保健院浙江湖州313000

目的探讨叶酸代谢基因检测指导孕妇科学服用叶酸在降低胎儿神经管畸形发生率中的作用。方法根据湖州市妇幼保健院产前门诊不同时期推荐叶酸服用方案,选取2016年1月—2017年12月7975例孕妇作为对照组,2020年1月—2021年12月11475例孕妇... 详细信息

目的探讨叶酸代谢基因检测指导孕妇科学服用叶酸在降低胎儿神经管畸形发生率中的作用。方法根据湖州市妇幼保健院产前门诊不同时期推荐叶酸服用方案,选取2016年1月—2017年12月7975例孕妇作为对照组,2020年1月—2021年12月11475例孕妇作为观察组。观察组进行叶酸代谢基因检测,根据检测结果给予个性化叶酸补充指导,对照组未经基因检测,按照常规剂量进行叶酸补充。分析观察组叶酸代谢基因检测结果,并评估其叶酸利用能力风险等级,比较两组胎儿神经管畸形发生情况。结果观察组孕妇亚甲基四氢叶酸还原酶(MTHFR)677CC、MTHFR 677CT、MTHFR 677TT基因型分布比例分别为36.45%、46.90%、16.64%。观察组孕妇叶酸利用能力低度风险、中度风险、重度风险比例分别为42.00%、28.00%、30.00%。观察组胎儿神经管畸形总发生率为0.64%,低于对照组的1.83%,差异有统计学意义(χ^(2)=60.307,P<0.05)。结论孕妇进行叶酸代谢基因检测十分必要,根据检测结果指导孕妇进行叶酸补充具有科学性,能够有效降低胎儿神经管畸形发生率。

关键词：叶酸基因检测胎儿神经管畸形

基于BIRCH聚类的航空器自主运行风险状态评价

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中国安全生产科学技术 2024年第9期20卷 188-196页

作者：张洪海沈雪瞿昕宜张世佳张纵驰唐思嘉南京航空航天大学民航学院江苏南京210000

为解决自主运行模式下航空器风险评价指标缺失和风险状态实时评估困难等问题,提出1种自主运行模式下航空器风险状态评价方法。从航空器冲突、气象规避区侵入、操纵裕度3个方面建立风险状态评价指标体系,运用BIRCH算法建立聚类特征树对... 详细信息

为解决自主运行模式下航空器风险评价指标缺失和风险状态实时评估困难等问题,提出1种自主运行模式下航空器风险状态评价方法。从航空器冲突、气象规避区侵入、操纵裕度3个方面建立风险状态评价指标体系,运用BIRCH算法建立聚类特征树对多维航空器特征样本进行风险模型训练,引入增量式聚类的概念,更新特征树,实时评估动态目标航空器的风险状态。然后,以广州05扇区为运行场景展开仿真实验。研究结果表明:所提方法准确度达99.5%,平均计算时间约为0.0249 s。研究结果可有效支撑自主运行理念实施,提高风险预警能力,保障航空器自主运行安全。

关键词：航空运输自主运行风险状态指标 BIRCH聚类