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Cadmium uptake and speciation changes in the rhizosphere of cadmium accumulator and non-accumulator oilseed rape varieties

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Journal of Environmental Sciences 2009年第8期21卷 1125-1128页

作者： SU Dechun xing jianping JIAO Weiping WONG Woonchung College of Resources and Environmental Sciences China Agricultural University Beijing 100193 China Department of Biology Hong Kong Baptist University Kowloon Tong Hong Kong SAR China

Characteristics of cadmium （Cd） uptake kinetics and distribution of Cd speciation in the rhizosphere for Cd accumulator and nonaccumulator oilseed rape varieties were investigated under nutrient solution and rhizobox soil culture conditions. The results showed that the maximal influx （Vmax） for Cd^2＋ and Km were significantly different for the two oilseed rape varieties. The value of Vmax for Cd accumulator oilseed rape Zhucang Huazi was two-fold greater than that for oilseed rape Chuan you Ⅱ-93. The exchangeable Cd concentration in the rhizosphere was significantly lower than in non-rhizospheric soils supplemented with CdSO4 for both the varieties. Carbonate-bound Cd in the rhizosphere of Cd accumulator oilseed rape was significantly higher than that in the rhizosphere of nonaccumulator oilseed rape and non-rhizospheric soil. Cd accumulator oilseed rape had a higher Cd^2＋ affinity and more ability to uptake insoluble Cd in the soil than the non-accumulator oilseed rape.

关键词： cadmium oilseed rape rhizosphere uptake kinetics

基于改进Stacking模型的铁路信号设备故障率预测

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机械与电子 2024年第1期42卷 41-46页

作者：袁武民邢建平杨栋兰州深蓝图形技术有限公司甘肃兰州730010 中国铁路兰州局集团有限公司兰州高铁基础设施段甘肃兰州730050 中国铁路兰州局集团有限公司银川电务段宁夏银川750021

针对单一机器学习模型在预测设备故障率的应用场景中存在误差大、精度低的问题,提出一种基于改进Stacking融合模型对铁路信号设备进行故障率预测的方法。采用XGBoost、LightGBM、CatBoost和逻辑回归方法构建基本Stacking模型,在此基础... 详细信息

针对单一机器学习模型在预测设备故障率的应用场景中存在误差大、精度低的问题,提出一种基于改进Stacking融合模型对铁路信号设备进行故障率预测的方法。采用XGBoost、LightGBM、CatBoost和逻辑回归方法构建基本Stacking模型,在此基础上引入Prophet时间序列预测模型,将Prophet模型提取的时序特征与基本Stacking模型逐级融合,构建改进后的Stacking-Prophet预测模型。最后以某单位信号设备数据为例,验证预测模型有效性。实验结果表明,相较单一预测模型,Stacking-Prophet预测模型均方根误差(RMSE)平均降低了94.14%,预测精度有较大的提升,对设备运维有一定的参考价值。

关键词：机器学习融合模型时间序列铁路信号设备故障率预测

Study on video intelligent early warning and tracking system based on ARM

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High Technology Letters 2016年第3期22卷 266-272页

作者：刘岩松 Xu Yihong xing jianping School of Mechanical and Electrical Engineering Shandong Management University Jinan 250357 P. R. China School of Information Science and Engineering Shandong University Jinan 250014 P. R. China

The protrusion of the planning of numerical intelligent early-warning and tracking system in this study which can ease triggerman's work strength,lay the next generation intelligence supervision system foundation and expand effectively the video resources use etc. In the numerical intelligent early-warning matrix sub-system,the authors have designed a kind dual-core system which includes both ARM and DSP,and designed detailedly traffic dynamics affairs early-warning arithmetic which bases on that system. And then,this system will carry quickly on fixing the right position of license plate,correcting the inclination degree of license plate,and thinning it to get the number of this license and severity grade. Secondly,in the rotated dome camera sub-system,the authors have designed three-dimensional trajectory mathematical model which makes use of a fuzzy PID controller to achieve the high- speed track. At last,Simulation shows that the proposed control method has high profile tracking precision,accuracy and robustness of the disturbance.

关键词： embedded dual-core system intelligent early warning accident recognition tracking and monitoring simulation

Study on concentration distribution and detonation characteristics for non-axisymmetric fuel dispersal

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Defence Technology（防务技术） 2024年第1期31卷 484-495页

作者： Linghui Zeng Zhongqi Wang xing Chen jianping Li State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China College of Environment and Chemical Engineering Sichuan University of Science&EngineeringZigong643000China

The study of non-axisymmetric fuel dispersal and detonation can provide reference for the prevention of industrial cloud explosion accidents and the design of fuel air explosive(FAE).The concentration and detonation fields of 85 kg cylindrical and fan-shaped fuel are investigated by experiments and numerical simulations.A dynamic model of the whole process for fuel dispersal and detonation is *** concentration distribution of fuel is used as the initial condition to calculate the detonation stage,thus solving the initial value problem of detonation *** phase and component changes of fuel cloud at different locations are *** fuel cloud is divided into directions of 0°,90°,135°and 180°.The results show that the maximum cloud radius is 20.94 m in 135°and the minimum is 12.04 m in 0°.The diameter of the detonation fireball is 53.6 m,and the peak temperature is 3455 *** highest peak overpressure is 3.44 MPa in 0°and the lowest is 2.97 MPa in 135°.The proportion of liquid phase in 0°is22.90%,and the fuel loss is 11.8% and 9% higher than that in 135°and cylindrical charge,*** stable propagation distance of blast wave in 135°is 42.50% longer than 0°and 28.37% longer than cylindrical charge.

关键词： Fuel dispersal Concentration distribution Detonation characteristic Fuel loss Numerical simulation

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海南琼中山栏稻产业发展现状与对策

热带农业科学 2024年第1期44卷 33-38页

作者：易伟鹏袁潜华唐清杰邢建平冯尔勇曹林奎海南省农业生态与资源保护总站海南海口571100 海南省农业农村厅GEF项目工作领导小组办公室海南海口571100 海南大学热带作物学院海南海口570228 海南省农业科学院粮食作物研究所海南海口571100 海南省琼中黎族苗族自治县农业农村局海南琼中572923 上海交通大学农业与生物学院上海200240

琼中黎族苗族自治县是海南岛山栏稻种植相对集中和典型的地区,科学保护和合理利用山栏稻种质资源,既是保护区域生物多样性、维持地区生态系统平衡的要求,也是传承海南地区农耕文化、保护独特农业文化遗产的需要。文章全面分析琼中山栏... 详细信息

琼中黎族苗族自治县是海南岛山栏稻种植相对集中和典型的地区,科学保护和合理利用山栏稻种质资源,既是保护区域生物多样性、维持地区生态系统平衡的要求,也是传承海南地区农耕文化、保护独特农业文化遗产的需要。文章全面分析琼中山栏稻产业发展现状与问题、市场前景并提出对策建议,旨在为加强琼中山栏稻种质资源保护与开发利用,提升其产业化发展水平,促进山栏稻产业的可持续发展提供参考。

关键词：琼中山栏稻产业发展现状对策建议

维普期刊数据库博看期刊

Upgrade of Goosy Data Acquisition System

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IMP & HIRFL Annual Report 1996年第1期 110-111页

作者： Wang Shujin Wang Yanyu xing jianping Guo Tianrui and Jiao Dunpang

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ＵｐｇｒａｄｅｏｆＧｏｏｓｙＤａｔａＡｃｑｕｉｓｉｔｉｏｎＳｙｓｔｅｍ￥ＷａｎｇＳｈｕｊｉｎ；ＷａｎｇＹａｎｙｕ；ＸｉｎｇＪｉａｎｐｉｎｇ；ＧｕｏＴｉａｎｒｕｉａｎｄＪｉａｏＤｕｎｐａｎｇＡｄａｔａａｃｑｕｉｓｉｔｉｏｎｓｙｓｔｅｍｎａｍｅｄＧｏｏｓ...

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A new coupled method for pseudolite system-augmented GNSS real-time kinematic PPP

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A new coupled method for pseudolite system-augmented GNSS re...

随机通信半径下无线传感器网络中三维节点定位算法(英文)

第十四届中国卫星导航年会

作者： Caoming Fan Zheng Yao Yanchen Dong jianping xing Shandong University Tsinghua University

A long convergence time for Global Navigation Satellite System(GNSS) Precise Point Positioning(PPP) is a critical obstacle to its wide *** pseudolites(PLs) are relatively close to receivers,moving receivers can produce rapid spatial geometry variations,which facilitates fast convergence of ***,considering the limited coverage of pseudolite system(PLS),the augmentation time is *** is therefore crucial to make the GNSS PPP parameters(especially the GNSS ambiguity parameters) converge within the limited augmentation ***,the potential of PLS should be explored as much as possible,and the gains brought by PLS should be effectively *** order to use the fixed solution of PLS more safely and reliably,a dual-filter tightly coupled(DF-TC) model is *** the number of PLs is sufficient and the augmentation time is long enough,the positioning performances of all the couple models are not significantly *** the case of short-time augmentation,the DF-TC model exhibits the best augmentation performance,it can significantly reduce the augmentation time required by GNSS,which means that the required coverage of PLS can be smaller and will be more flexible and convenient for applications.

关键词：

来源： cnki会议评论

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传感技术学报 2011年第1期24卷 88-92页

作者：刘洋邢建平山东大学信息科学与工程学院济南250100

在无线传感器网络三维节点定位问题中,节点通信半径是一个关键参数,通过这个参数,节点建立整个网络的连接度,以实现自身定位。大多数的定位算法中,这个参数通常被设定为一个常数,但这种假设有悖于事实,一般情况下这个参数很难控制,它受... 详细信息

在无线传感器网络三维节点定位问题中,节点通信半径是一个关键参数,通过这个参数,节点建立整个网络的连接度,以实现自身定位。大多数的定位算法中,这个参数通常被设定为一个常数,但这种假设有悖于事实,一般情况下这个参数很难控制,它受到很多因素的影响,比如检测区域中的障碍物阻隔,节点硬件设计的限制以及功率控制等。正是考虑到了这个特殊的问题,介绍了一种最优空间跳跃距离获取以及最优锚节点选择机制,而为了更好的模拟真实环境中的多变情况,每一个节点的通信半径都被设置为20 m至90 m之间的一个随机值。在最后,通过仿真结果,验证了文中提出的三维节点定位算法非常适合无线传感器网络中节点拥有随机半径的问题。

关键词：无线传感器网络随机通信半径最优空间跳跃距离锚节点选择

^_(57)Fe Mossbauer Effect Study of Sm_(2)Fe_(17) under Different Heat Treatment Conditions

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IMP & HIRFL Annual Report 1995年 170-171页

作者： Chen Xiaoxi Liu Guichuan Niu Mulin Meng Qinghua xing jianping Xu Zhengjia Zu Kailing 不详 San Huan Research Laboratory Chinese Academy of SciencesBejing

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关键词： C?