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Quantification of irrigation water transport processes in ZiZiphus jujuba garden using water stable isotopes
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作者 ZHONG Xiaofei ZHANG Mingjun +3 位作者 CHE Cunwei LIU Zechen LI Beibei ZHANG Yuanyuan 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3263-3274,共12页
ZiZiphus jujuba,which is native to China,has become one of the main crops widely planted in the western Loess Plateau because of its drought and flood-tolerance,adaptability,and higher nutritional value of the fruit.T... ZiZiphus jujuba,which is native to China,has become one of the main crops widely planted in the western Loess Plateau because of its drought and flood-tolerance,adaptability,and higher nutritional value of the fruit.The irrigation water infiltration in Z.jujuba gardens is complex,and understanding its mechanisms is essential for efficient water use and sustainable agriculture.This knowledge helps ensure the long-term success of jujuba cultivation.This paper describes a field experiment that investigates the infiltration process of irrigation water from Z.jujuba garden and quantifies the contribution of irrigation water to soil water at different depths using the MixSIAR model.According to the FC(Field water holding Capacity)of Z.jujuba,irrigation experiments with three volumes of 80%FC,60%FC,and 40%FC are set up in this study.The study finds that water retention is better in Z.jujuba garden soils with a higher proportion of coarse gravel in the soil particle composition.Soil water content exhibits a gradient change after irrigation,with deeper wetting front transport depth observed with increased irrigation water.Additionally,there is correlation between soil temperature and soil water content.The soil water in Z.jujuba garden generally exhibits a preferential flow signal in the 0-40 cm range.Below 40 cm,a piston flow pattern dominates.The rate of soil water infiltration increases with the amount of irrigation water.In the 0-40 cm range of the soil vertical profile,irrigation water was the main contributor to soil water.Z.jujuba demonstrated flexibility in water uptake,primarily absorbing soil water at depths of 0-40 cm.For optimal growth of Z.jujuba at this stage,40%FC irrigation is recommended.The results are expected to be valuable future irrigation practices and land use planning for Z.jujuba garden in arid zones,supporting sustainable agricultural development and water management. 展开更多
关键词 Water stable isotopes different irrigation volumes ZiZiphus jujuba Irrigation water infiltration process MixSIAR model
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Damage Processes of Polypropylene Fiber Reinforced Mortar in Different Fiber Content Revealed by Acoustic Emission Behavior 被引量:3
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作者 王岩 CHEN Shijie +2 位作者 XU Zhengzheng LIU Shaojun HU Hongxiang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第1期155-163,共9页
The performances of the cement-based materials can be improved by the incorporation of polypropylene fiber, but the damage processes become more complex with different fiber contents at the same time. The acoustic emi... The performances of the cement-based materials can be improved by the incorporation of polypropylene fiber, but the damage processes become more complex with different fiber contents at the same time. The acoustic emission(AE) technology can achieve the global monitoring of internal damage in materials. The evolution process of failure mode and damage degree of polypropylene fiber reinforced mortar and concrete were analyzed by measuring the AE energy, RA value, AF value and b value. It was found that the cement matrix cracked on the initial stage, the cracks further developed on the medium stage and the fibers were pulled out on the last stage. The matrix cracked with minor injury cracks, but the fiber broke with serious damage cracks. The cumulative AE energy was proportional to the polypropylene fiber reinforced concrete and mortar's ductility. The damage mode and damage degree can be judged by identifying the damage stage obtained by the analysis of the AF value. 展开更多
关键词 polypropylene fiber different content MORTAR concrete acoustic emission damage processes
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Effect of unequal injection rates and different hopping rates on asymmetric exclusion processes with junction 被引量:1
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作者 肖松 蔡九菊 +1 位作者 刘飞 刘明哲 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期42-52,共11页
In this paper, the effects of unequal injection rates and different hopping rates on the asymmetric simple exclusion process (ASEP) with a 2-input 1-output junction are studied by using a simple mean-field approach ... In this paper, the effects of unequal injection rates and different hopping rates on the asymmetric simple exclusion process (ASEP) with a 2-input 1-output junction are studied by using a simple mean-field approach and extensive computer simulations. The steady-state particle currents, the density profiles, and the phase diagrams are obtained. It is shown that with unequal injection rates and different hopping rates, the phase diagram structure is qualitatively changed. The theoretical calculations are in good agreement with Monte Carlo simulations. 展开更多
关键词 asymmetric simple exclusion processes mean-field approximation JUNCTION different hopping rates
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An investigation of ionizing radiation damage in different SiGe processes 被引量:1
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作者 李培 刘默寒 +3 位作者 贺朝会 郭红霞 张晋新 马婷 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第8期551-556,共6页
Different SiGe processes and device designs are the critical influences of ionizing radiation damage. Based on the different ionizing radiation damage in SiGe HBTs fabricated by Huajie and an IBM SiGe process, quantit... Different SiGe processes and device designs are the critical influences of ionizing radiation damage. Based on the different ionizing radiation damage in SiGe HBTs fabricated by Huajie and an IBM SiGe process, quantitatively numerical simulation of ionizing radiation damage was carried out to explicate the distribution of radiation-induced charges buildup in KT9041 and IBM SiGe HBTs. The sensitive areas of the EB-spacer and isolation oxide of KT9041 are much larger than those of the IBM SiGe HBT, and the distribution of charge buildup in KT9041 is several orders of magnitude greater than that of the IBM SiGe HBT. The result suggests that the simulations are consistent with the experiment, and indicates that the geometry of the EB-spacer, the area of the Si/SiO2 interface and the isolation structure could be contributing to the different ionizing radiation damage. 展开更多
关键词 different silicon-germanium process ionizing radiation damage numerical simulation
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Hydrological Processes of Storm Runoff from Catchments of Different Land Uses
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作者 HONG Lin LI Minggang SONG Yuansheng 《Wuhan University Journal of Natural Sciences》 CAS 2007年第2期317-321,共5页
In this paper, a novel and efficient study on the hydrological processes of storm runoff from catchments of different land uses is conducted. The motivation is to precisely simulate the hydrological processes of storm... In this paper, a novel and efficient study on the hydrological processes of storm runoff from catchments of different land uses is conducted. The motivation is to precisely simulate the hydrological processes of storm runoff in the agricultural catchments with different patterns of land uses, i.e., forest, paddy, and upland, respectively. As it is discussed in this paper, different land use leads to different characteristics of storm runoff. In order to understand the changes in the hydrological processes of storm runoff from catchments of different land uses, the effects of rainfall intensity, initial soil moisture deficit, evapotranspiration rate, percolation rate, and retention capacity on hydrological processes of the catchments are taken into consideration. According to the principle of water balance, a general model to connect the separate hydrological processes is developed; then, the individual hydrological process is studied in detail: Firstly, the daily evaporation is calculated according to the relation between the actual evapotranspiration and the potential evapotranspiration rate; Secondly, the retention of storm runoff is plotted against the total rainfall, and the maximum storage is calculated; Thirdly, the percolation rate is calculated for each catchment. 展开更多
关键词 storm runoff hydrological process CATCHMENTS different land use
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Effects of Nitrogen on Grain Yield,Nutritional and Processing Quality of Wheat for Different End Uses 被引量:6
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作者 ZHU Xin-kai, GUO Wen-shan, ZHOU Jun-liang, HU Hong, ZHANG Ying, LI Chun-yan, FENG Chao-nian and PENG Yong-xin(Agricultural College of Yangzhou University , Yangzhou 225009 , P. R. China) 《Agricultural Sciences in China》 CAS CSCD 2003年第6期609-616,共8页
The effects of nitrogen on grain yield, nutritional quality and processing quality of wheat for different end uses were studied in Yangzhou from 2000 to 2002. Increasing N application amount and/or the ratio of topdre... The effects of nitrogen on grain yield, nutritional quality and processing quality of wheat for different end uses were studied in Yangzhou from 2000 to 2002. Increasing N application amount and/or the ratio of topdressing N after elongation stage could raise grain yield, protein content, wet gluten content, sedimentation, falling number, development time and stability time. To produce strong-gluten and medium-gluten wheat, the suitable ratio of basis : tillering : elongation : booting N fertilizer was 3:1:3:3or5:1:2:2 with 180 - 240 kg N ha-1. To produce weak-gluten wheat, the ratio of basis : tillering : elongation N fertilizer should be 7 : 1 : 2 with 180 kg N ha-1 and 240×104 ha-1 seedlings. 展开更多
关键词 Winter wheat for different end uses NITROGEN Nutritional quality processing quality Grain yield
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AWeighted Average Finite Difference Scheme for the Numerical Solution of Stochastic Parabolic Partial Differential Equations
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作者 Dumitru Baleanu Mehran Namjoo +1 位作者 Ali Mohebbian Amin Jajarmi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1147-1163,共17页
In the present paper,the numerical solution of It?type stochastic parabolic equation with a timewhite noise process is imparted based on a stochastic finite difference scheme.At the beginning,an implicit stochastic fi... In the present paper,the numerical solution of It?type stochastic parabolic equation with a timewhite noise process is imparted based on a stochastic finite difference scheme.At the beginning,an implicit stochastic finite difference scheme is presented for this equation.Some mathematical analyses of the scheme are then discussed.Lastly,to ascertain the efficacy and accuracy of the suggested technique,the numerical results are discussed and compared with the exact solution. 展开更多
关键词 Itoequation stochastic process finite difference scheme stability and convergence CONSISTENCY
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Label-Free and Real-Time Monitor of Binding and Dissociation Processes between Protein A and Swine IgG by Oblique-Incidence Reflectivity Difference Method
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作者 何立平 刘爽 +6 位作者 戴俊 吴琳 刘国振 韦汉福 吕惠宾 金奎娟 杨国桢 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第2期35-38,共4页
Life science has a need for detection methods that are label-free and real-time. In this paper, we have selected staphylococcal protein A (SPA) and swine immunoglobulin G (IgG), and monitor the bindings between SP... Life science has a need for detection methods that are label-free and real-time. In this paper, we have selected staphylococcal protein A (SPA) and swine immunoglobulin G (IgG), and monitor the bindings between SPA and swine IgG with different concentrations, as well as the dissociations of SPA-swine IgG complex in different pH values of phosphate buffer by oblique-incidence reflectivity difference (OIRD) in a label-free and real-time fashion. We obtain the ON and OFF reaction dynamic curves corresponding to the bindings and dissociations of SPA and swine IgG. Through our analysis of the experimental results, we have been able to obtain the damping coefficients and the dissociation time of SPA and swine IgG for different pH values of the phosphate buffer. The results prove that the OIRD technique is a competing method for monitoring the dynamic processes of biomolecule interaction and achieving the quantitative information of reaction kinetics. 展开更多
关键词 SPA pH Label-Free and Real-Time Monitor of Binding and Dissociation processes between Protein A and Swine IgG by Oblique-Incidence Reflectivity difference Method IGG
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Mutagenicity and Genotoxicity of Organic Extracts from Finished Water with Different Treatment Process
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作者 FANG Dao Kui ZHOU Guo Hong +1 位作者 YU Shu Yuan FENG Jin Shu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第8期632-636,共5页
Purification of surface water is widely practiced with conventional water treatment processes like coagulation-flocculation, sedimentation, filtration,and disinfection. Some reports have specified that conventional wa... Purification of surface water is widely practiced with conventional water treatment processes like coagulation-flocculation, sedimentation, filtration,and disinfection. Some reports have specified that conventional wastewater purification processes do not effectively remove many chemical contaminants, 展开更多
关键词 Mutagenicity and Genotoxicity of Organic Extracts from Finished Water with different Treatment process
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Second-order difference scheme for a nonlinear model of wood drying process
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作者 姜明杰 孙志忠 《Journal of Southeast University(English Edition)》 EI CAS 2006年第4期582-588,共7页
A numerical simulation for a model of wood drying process is considered. The model is given by a couple of nonlinear differential equations. One is a nonlinear parabolic equation and the other one is a nonlinear ordin... A numerical simulation for a model of wood drying process is considered. The model is given by a couple of nonlinear differential equations. One is a nonlinear parabolic equation and the other one is a nonlinear ordinary equation. A difference scheme is derived by the method of reduction of order. First, a new variable is introduced and the original problem is rewritten into a system of the first-order differential equations. Secondly, a difference scheme is constructed for the later problem. The solvability, stability and convergence of the difference scheme are proved by the energy method. The convergence order of the difference scheme is secondorder both in time and in space. A prior error estimate is put forward. The new variable is put aside to reduce the computational cost. A numerical example testifies the theoretical result. 展开更多
关键词 wood drying process model nonlinear differential equation difference scheme method of reduction of order STABILITY CONVERGENCE
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Effects of the differences between the ITRF2000 and ITRF2005 models in GNSS data processing 被引量:1
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作者 Zhan Wei Zhu Shuang +3 位作者 Yang Bo Wu Yanqiang Liu Zhiguang Meng Xiangang 《Geodesy and Geodynamics》 2013年第4期46-50,共5页
In comparison with the ITRF2000 model, the ITRF2005 model represents a significant improvement in solution generation, datum definition and realization. However, these improvements cause a frame difference between the... In comparison with the ITRF2000 model, the ITRF2005 model represents a significant improvement in solution generation, datum definition and realization. However, these improvements cause a frame difference between the ITRF2000 and ITRF2005 models, which may impact GNSS data processing. To quantify this im- pact, the differences of the GNSS results obtained using the two models, including station coordinates, base- line length and horizontal velocity field, were analyzed. After transformation, the differences in position were at the millimeter level, and the differences in baseline length were less than 1 ram. The differences in the hori- zontal velocity fields decreased with as the study area was reduced. For a large region, the differences in these value were less than 1 mm/a, with a systematic difference of approximately 2 degrees in direction, while for a medium-sized region, the differences in value and direction were not significant. 展开更多
关键词 ITRF2000 ITRF2005 GNSS data processing differENCE effect
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Measurement of intensity difference squeezing via non-degenerate four-wave mixing process in an atomic vapor
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作者 于旭东 孟增明 张靖 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期415-420,共6页
We report the measurement of the intensity difference squeezing via the non-degenerate four-wave mixing process in a rubidium atomic vapor medium. Two pairs of balanced detection systems are employed to measure the pr... We report the measurement of the intensity difference squeezing via the non-degenerate four-wave mixing process in a rubidium atomic vapor medium. Two pairs of balanced detection systems are employed to measure the probe and the conjugate beams, respectively. It is convenient to get the quantum shot noise limit, the squeezed and the amplified noise power spectra. We also investigate the influence of the input extra quadrature amplitude noise of the probe beam. The influence of the extra noise can be minimized and the squeezing can be optimized under the proper parameter condition. We measure the -3.7-dB intensity difference squeezing when the probe beam has a 3-dB extra quadrature amplitude noise. This result is slightly smaller than -4.1 dB when the ideal coherent light (no extra noise) for the probe beam is used. 展开更多
关键词 four-wave mixing process intensity difference squeezing self-balanced detection
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Numerical Simulation of Foaming Processes
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作者 Katharina Gladbach Antonio Delgado Cornelia Rauh 《World Journal of Mechanics》 2017年第11期297-322,共26页
The literature model studied in this article describes bubble formation and growth in a highly viscous polymer liquid with support of a gaseous matter dispersed under pressure before foaming. The foam growth is induce... The literature model studied in this article describes bubble formation and growth in a highly viscous polymer liquid with support of a gaseous matter dispersed under pressure before foaming. The foam growth is induced by the application of vacuum and mass transport of volatile components dissolved in the polymer liquid. Based on this literature model, aeration processes are calculated for intermediate viscosity and low viscosity biological systems, as they are of interest for biomatter foams, in particular for food foams in industrial processes. At the end of this article, the numerical results are presented and discussed. 展开更多
关键词 FOAMING process CONSERVATION EQUATIONS Finite differENCE Method Convergence Analysis REYNOLDS Number NEWTONIAN Liquids
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基于炮制原理研究《中国药典》炒桃仁标准的合理性 被引量:1
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作者 翟为民 文佳 +8 位作者 徐新房 张海霞 李千 王煜杰 姜水蓝 刘艺淇 张欣悦 杨超 李向日 《中国现代中药》 CAS 2024年第6期1048-1052,共5页
目的:在“杀酶保苷”的基础上,进一步探究《中华人民共和国药典》(以下简称《中国药典》)2020年版炒桃仁的炮制原理。方法:采用高效液相色谱法探究桃仁炒制过程中苦杏仁苷的变化规律,测色计测定桃仁炒制中明度指数(L^(*))、红绿指数(a^(... 目的:在“杀酶保苷”的基础上,进一步探究《中华人民共和国药典》(以下简称《中国药典》)2020年版炒桃仁的炮制原理。方法:采用高效液相色谱法探究桃仁炒制过程中苦杏仁苷的变化规律,测色计测定桃仁炒制中明度指数(L^(*))、红绿指数(a^(*))、黄蓝指数(b^(*))的变化;利用多元回归分析方法探索桃仁炮制过程中色差与其苦杏仁苷含量变化的相关性。结果:桃仁燀后再炒,至见焦斑,D-苦杏仁苷含量显著增加,L-苦杏仁苷含量下降,总苦杏仁苷含量基本一致;再炒,焦斑明显时D-苦杏仁苷含量下降。不同炒制程度桃仁中D-苦杏仁苷含量与a^(*)值呈显著正相关,与b^(*)值呈显著负相关。结论:燀桃仁微炒促进L-苦杏仁苷向D-苦杏仁苷转化,使D-苦杏仁苷含量增加,D-苦杏仁苷的含量会逐渐降低,故应避免炮制过度;桃仁炮制过程中颜色改变与其有效成分含量变化具有相关性;《中国药典》2020年版中关于炒桃仁性状描述及含量测定限度规定合理,符合炮制目的,有助于保证炒桃仁饮片的质量。 展开更多
关键词 炒桃仁 炮制原理 苦杏仁苷 炮制火候 色差
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车用燃料电池散热性能实验研究 被引量:1
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作者 白静 范惠芳 +7 位作者 崔四齐 许闯 张毅 关斯泽 杨涵斐 贾一飞 耿树伟 郑慧凡 《储能科学与技术》 CAS CSCD 北大核心 2024年第2期390-395,共6页
质子交换膜燃料电池(PEMFC)作为能效转换率高、清洁可靠的发电装置,在交通、储能、航天及军事等领域有着广泛应用。为了解决质子交换膜燃料电池散热密度高、发热量大、散热效率低等突出问题,本文针对散热量为15 kW的质子交换膜燃料电池... 质子交换膜燃料电池(PEMFC)作为能效转换率高、清洁可靠的发电装置,在交通、储能、航天及军事等领域有着广泛应用。为了解决质子交换膜燃料电池散热密度高、发热量大、散热效率低等突出问题,本文针对散热量为15 kW的质子交换膜燃料电池,设计并搭建了一套具有四种不同流程换热器的车用燃料电池散热系统实验台。分别使用两相冷却工质HFE-7100和乙二醇水溶液作为冷却工质,探究了在35℃的高温环境中,两种工质在不同流程换热器和不同工质流量下的散热性能和系统能效比(Energy Efficiency Rating, EER)。结果表明,在相同的流程下,采用HFE-7100两相散热方式相对于采用乙二醇水溶液液冷散热方式散热量提升率在81.2%~98.8%之间,系统EER提升率在68.2%~88.6%之间。且在4种不同流程下,3流程的系统散热效果和节能效果最佳,两相工质HFE-7100散热量和系统EER分别达到14.4 kW和20.5 kW/kW,液冷工质乙二醇水溶液散热量和系统EER分别达到7.7 kW和12.1 kW/kW。冷却工质流量为4 L/min时,系统节能效果较好,其两相和液冷散热系统EER分别能达到20.9 kW/kW和10.5 kW/kW。 展开更多
关键词 质子交换膜燃料电池 不同流程换热器 两相冷却工质 EER
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云南冬季强降温过程冷空气路径及大气环流差异
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作者 姚愚 晏红明 《云南大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期94-105,共12页
基于云南125个测站日平均气温数据,判定了1961—2020年云南冬季95次强降温过程的4种冷空气路径,对比分析了不同路径冷空气对云南降温的影响及大气环流差异.结果表明,东北路径冷空气对云南降温幅度影响最剧烈、影响空间范围最广;偏东路... 基于云南125个测站日平均气温数据,判定了1961—2020年云南冬季95次强降温过程的4种冷空气路径,对比分析了不同路径冷空气对云南降温的影响及大气环流差异.结果表明,东北路径冷空气对云南降温幅度影响最剧烈、影响空间范围最广;偏东路径出现频率最高,偏东路径和偏北路径在降温幅度和影响范围上较为接近;东南路径降温幅度和影响范围最弱,出现频率最低.超前强降温日2 d时,东北路径欧亚大陆500 hPa位势高度场上正高度距平异常区域强度和面积、700 hPa反气旋距平环流强度和西伯利亚高压均为最强,东南路径最弱,偏东路径和偏北路径介于前二者之间.东北路径500 hPa上东亚槽横槽转竖特征最明显,偏东路径和偏北路径东亚槽槽底南压加深,但转竖特征不及东北路径明显;东南路径东亚槽底部较宽广;东北路径副高呈块状面积最小,其它3种路径副高则呈带状,偏东路径副高面积最大.700 hPa上东北路径和偏东路径在日本附近有较强海平面气压负距平发展,朝鲜半岛气旋距平环流较强,其西侧较强的偏北气流引导冷空气进入云南;东南路径和偏北路径在朝鲜半岛气旋距平环流及其西侧的偏北气流较弱.在200 hPa纬向风距平场上,东北路径急流轴附近正负距平区强度最强,偏东路径沿急流轴距平分布为西正东负;东南路径正负距平区强度最弱,负距平区主要分布在急流轴北侧,偏北路径负距平区分布在急流轴南北两侧. 展开更多
关键词 云南 冬季 强降温过程 冷空气路径 环流差异
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基于现场可编程门阵列的水果识别系统设计
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作者 金梅 曾欣 +2 位作者 张立国 冯景瑞 吴文哲 《高技术通讯》 CAS 北大核心 2024年第6期616-623,共8页
针对目前大多数水果识别系统实时性差和成本较高的问题,本文提出一种基于现场可编程门阵列(FPGA)的水果识别系统。整体硬件设计包含图像采集、检测识别和显示模块。软件部分通过图像采集平台将水果图像存储至双倍数据率同步动态随机存储... 针对目前大多数水果识别系统实时性差和成本较高的问题,本文提出一种基于现场可编程门阵列(FPGA)的水果识别系统。整体硬件设计包含图像采集、检测识别和显示模块。软件部分通过图像采集平台将水果图像存储至双倍数据率同步动态随机存储器(DDR3)控制模块,进行图像灰度化处理,并创造性地提出背景帧差法对水果图像进行分割。通过融合水果颜色和几何特征,实现对水果数量、颜色和种类的识别。整个水果识别系统在不同光照下对常见水果进行了测试。实验结果表明,水果平均识别准确率达到93.25%,识别速度约为16.67 ms,FPGA硬件资源消耗率仅占28.02%,可以满足实时性需求。 展开更多
关键词 水果识别 背景帧差法 图像处理 现场可编程门阵列(FPGA)
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热加工铝5A06材料化学氧化膜的色差控制技术
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作者 仝晓刚 《电镀与精饰》 CAS 北大核心 2024年第6期85-89,共5页
设计并加工了铝5A06的热处理、氩弧焊以及电子束焊工艺样件。分别对3种样件进行了SEM形貌分析、能谱分析,分析结果表明3种处理方法均在样件表面生成了氧化膜,氩弧焊、电子束焊样件在热影响区、焊缝区形成了第二相。首先采用30%的盐酸去... 设计并加工了铝5A06的热处理、氩弧焊以及电子束焊工艺样件。分别对3种样件进行了SEM形貌分析、能谱分析,分析结果表明3种处理方法均在样件表面生成了氧化膜,氩弧焊、电子束焊样件在热影响区、焊缝区形成了第二相。首先采用30%的盐酸去除热处理、氩弧焊以及电子束焊样件表面的氧化膜,然后按照1∶3的比例采用HF酸和HNO_(3)的混合酸对3种样件进行酸侵蚀,最后对其进行化学氧化处理,结果表明3种样件表面的化学氧化膜色泽基本一致。 展开更多
关键词 热加工 铝5A06 化学氧化膜 色差
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考虑参数空间差异的复合式滑坡推力计算分析
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作者 赵健 姚嘉昊 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2024年第8期3189-3199,共11页
由于复合式滑坡不同滑区同一岩土计算参数数值存在差异性,导致滑坡推力大小判别难度加大。根据复合式滑坡破坏模式,概化构建滑坡地质模型,在此基础上建立滑坡物理力学模型,并对各区参数进行理论分析。根据滑坡失稳特征以及前人对复合式... 由于复合式滑坡不同滑区同一岩土计算参数数值存在差异性,导致滑坡推力大小判别难度加大。根据复合式滑坡破坏模式,概化构建滑坡地质模型,在此基础上建立滑坡物理力学模型,并对各区参数进行理论分析。根据滑坡失稳特征以及前人对复合式滑坡演化阶段划分的研究,将滑坡演化过程划分为前后裂隙开裂、前后滑带局部软化、前后滑带扩展、中部滑带软化、边坡整体失稳5个阶段,基于传递系数法和静力平衡条件构建不同演化阶段下的滑坡推力计算式。以汉巴南铁路某复合式滑坡为例,揭示了滑坡推力随水平距离增加的变化规律,并将计算结果与不考虑不同滑区同一岩土计算参数数值差异得出的计算结果进行对比分析。研究结果表明:1)在计算复合式滑坡推力时,考虑不同滑区同一岩土计算参数数值差异性的影响,其计算结果更加准确,规避因单一取值而导致计算推力不合理等问题。2)根据复合式滑坡不同演化阶段下的推力变化规律,在滑坡初期应以推移区和牵引区加固为主,当中部锁固区开始滑动,应以中部锁固区加固为主,同时也要加强推移区和牵引区的加固。3)在识别复合式滑坡演化阶段的基础上,根据此阶段构建的滑坡推力计算式得出推力空间变化规律,从而可提出较为合理的防治措施。 展开更多
关键词 复合式滑坡 演化过程 参数差异 传递系数法 推力计算
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大学生抗逆力形成历程及影响因素研究——以回溯不同年龄阶段丧亲经历为例
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作者 李成齐 李爽 《大理大学学报》 2024年第7期105-114,共10页
丧亲事件会对人的身心健康造成较大负面影响。为了解丧亲经历大学生的抗逆力形成历程及影响因素,探讨如何提升其心理健康水平,选择14名没有达到延长哀伤障碍诊断标准的大学生进行半结构化访谈,采用整体—内容模式对访谈文本进行叙事分... 丧亲事件会对人的身心健康造成较大负面影响。为了解丧亲经历大学生的抗逆力形成历程及影响因素,探讨如何提升其心理健康水平,选择14名没有达到延长哀伤障碍诊断标准的大学生进行半结构化访谈,采用整体—内容模式对访谈文本进行叙事分析。研究结果发现形成历程分为:得知死讯,不同年龄阶段的多元反应;直面丧亲,葬礼上不得不接受死亡的发生;生活重启,伤口与结痂同在等3个主题、13个次主题。影响因素分为家庭社会支持是否充足、意义重构是否完成等2个主题、7个次主题。应通过对高校学生生死教育与思想政治教育进行融合、引导丧亲者对丧亲意义进行重构、营造家庭—学校—社区协助育人的抗逆系统这三种途径提升大学生经历丧亲事件时的抗逆力,培养大学生形成健全的人格和良好的个性心理品质。 展开更多
关键词 丧亲大学生 抗逆力 形成历程 影响因素 不同年龄阶段
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