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Prediction of the globally ecological suitability of Panax quinquefolius by the geographic information system for global medicinal plants(GMPGIS)

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Chinese Journal of Natural Medicines 2019年第7期17卷 481-489页

作者： SHEN Liang LI xi-Wen MENG xiang-xiao WU Jie TANG Huan HUANG Lin-Fang xiAO Shui-ming XU Jiang CHEN Shi-Lin Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Beijing 100700 China Institute of Medicinal Plant Development (IMPLAD) Chinese Academy of Medical Sciences (CAMS) Peking Union Medical College (PUMC) Beijing 100193 China

American ginseng(Panax quinquefolius L.) is a well-known Asian traditional herbal medicine with a large market demand. The plant is native to eastern North America, and its main producing areas worldwide are decreasing due to continuous cropping obstacles and environmental changes. Therefore, the identification of maximum similarities of new ecological distribution of ***, and prediction of its response to climate change in the future are necessary for plant introduction and cultivation. In this study, the areas with potential ecological suitability for P. quinquefolius were predicted using the geographic information system for global medicinal plants(GMPGIS) based on 476 occurrence points and 19 bioclimatic variables. The results indicate that the new ecologically suitable areas for P. quinquefolius are East Asia and the mid-eastern Europe, which are mainly distributed in China, Russia, Japan, Ukraine, Belarus, North Korean, South Korea, and Romania. Under global climate change scenarios, the suitable planting areas for P. quinquefolius would be increased by 9.16%–30.97%, and expanding north and west over the current ecologically suitable areas by 2070. The potential increased areas that are ecologically suitable include northern Canada, Eastern Europe, and the Lesser Khingan Mountains of China, and reduced regions are mainly in central China, the southern U.S., and southern Europe. Jackknife tests indicate that the precipitation of the warmest quarter was the important climatic factor controlling the distribution of P. *** findings can be used as a useful guide for P. quinquefolius introduction and cultivation in ecologically suitable areas.

关键词： American ginseng Panax quinquefolius Ecological suitable area Climate change GMPGIS Jackknife test

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景洪水电厂新型全国产化计算机监控系统论述

云南水力发电 2024年第4期40卷 169-171页

作者：李鹤徐瑞周喜华能澜沧江水电股份有限公司景洪水电厂云南景洪666100

计算机监控系统是水电厂控制系统的核心,运行状况直接影响发电机安全稳定运行。随着国家关键核心技术自主掌控的要求,景洪水电站历经1 a左右的研发时间,新型国产化计算机监控系统终于研发成功,并在现场投入使用。重点论述了新型国产化... 详细信息

计算机监控系统是水电厂控制系统的核心,运行状况直接影响发电机安全稳定运行。随着国家关键核心技术自主掌控的要求,景洪水电站历经1 a左右的研发时间,新型国产化计算机监控系统终于研发成功,并在现场投入使用。重点论述了新型国产化监控系统的网络构架、硬件构成、软件构成、电源系统、数据传输机制、网络安全防护等关键技术。

关键词：计算机监控网络构架硬件软件数据传输网络安全

青藏公路沿线土壤重金属分布特征与污染风险评估

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土壤通报 2024年第4期55卷 1089-1098页

作者：吴婷李瑞张亭李鑫王云曹龙熹成都理工大学生态环境学院四川成都610059 成都理工大学地球科学学院四川成都610059 交通运输部科学研究院北京100029

【目的】摸清青藏公路沿线土壤重金属空间分布特征并进行污染风险评价,为沿路生态环境保护提供依据。【方法】沿青藏公路(西宁-那曲段)选择37个典型路段进行实地调查与土壤采样,由路基向外采集0 m、50 m和100 m处的表土样品共122个,测... 详细信息

【目的】摸清青藏公路沿线土壤重金属空间分布特征并进行污染风险评价,为沿路生态环境保护提供依据。【方法】沿青藏公路(西宁-那曲段)选择37个典型路段进行实地调查与土壤采样,由路基向外采集0 m、50 m和100 m处的表土样品共122个,测定土壤中的镉(Cd)、铅(Pb)和砷(As)含量。分别采用内梅罗污染指数(Ip)、地累积污染指数(Igeo)和潜在生态风险指数(RI),依据国家《农用地土壤污染风险筛选值》进行重金属污染风险评价。【结果】青藏公路沿线土壤中Cd、Pb和As的平均含量分别为0.13±0.05、33.20±14.64和18.10±18.25 mg kg−1,均大于土壤环境背景值。从路域横向变化趋势来看,公路路基边坡底部(0 m)的土壤重金属含量显著大于50 m和100 m处,且随公路距离的增加而下降。内梅罗污染指数的范围为0.17~0.88,总体位于未超标的安全线以下,但在格尔木-唐古拉山段存在局部超警戒值的点位。三种不同重金属元素的地累积指数结果表明Cd在大多数点位为无污染到中度污染之间的范围,另外两种重金属为无污染;公路沿线的潜在生态风险指数整体上属于轻微污染水平,但在格尔木-唐古拉山段局部存在150

关键词：重金属路域土壤青藏公路污染特征污染指数

SIMULATION OF HYDRAULIC TRANSIENTS IN HYDROPOWER SYSTEMS USING THE 1-D-3-D COUPLING APPROACH

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Journal of Hydrodynamics 2012年第4期24卷 595-604页

作者： ZHANG xiao-xi CHENG Yong-guang State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China

Although the hydraulic transients in pipe systems are usually simulated by using a one-dimensional （l-D） approach, local three-dimensional （3-D） simulations are necessary because of obvious 3-D flow features in some local regions of the hydropower systems. This paper combines the 1-D method with a 3-D fluid flow model to simulate the Multi-Dimensional （MD） hydraulic transients in hydropower systems and proposes two methods for modeling the compressible water with the correct wave speed, and two strategies for efficiently coupling the 1-D and 3-D computational domains. The methods are validated by simulating the water hammer waves and the oscillations of the water level in a surge tank, and comparing the results ~with the 1-D solution data. An MD study is conducted for the transient flows in a realistic water conveying system that consists of a draft tube, a tailrace surge tank and a tailrace tunnel. It is shown that the 1-D-3-D coupling approach is an efficient and promising way to simulate the hydraulic transients in the hydropower systems in which the interactions between 1-D hydraulic fluctuations of the pipeline systems and the local 3-D flow patterns should be considered.

关键词： hydropower station hydraulic transients compressible water model coupling of 1-D and 3-D methods

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信息化技术在智慧水利中的应用及思考

Adaptive sliding mode control for limit protection of aircraft engines

科学与信息化 2024年第4期 48-50页

作者：马莹程晖王晞长江水利委员会网络与信息中心湖北武汉 430000 长江水利委员会流域管理数字赋能技术创新中心湖北武汉 430000 水利部中国科学院水工程生态研究所湖北武汉 430000 水利部水工程生态效应与生态修复重点实验室湖北武汉 430000

智慧水利是当前水利发展的主要方向,各类信息技术联合应用是水资源合理分配调用、优化水治理机制的关键.基于此,本文对智慧水利的建设意义进行了分析,提出了基于信息化技术的智慧水利应用以及未来发展方向,以期为智慧水利的快速发展提... 详细信息

智慧水利是当前水利发展的主要方向,各类信息技术联合应用是水资源合理分配调用、优化水治理机制的关键.基于此,本文对智慧水利的建设意义进行了分析,提出了基于信息化技术的智慧水利应用以及未来发展方向,以期为智慧水利的快速发展提供助力.

关键词：信息化技术智慧水利应用发展趋势数字孪生

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Chinese Journal of Aeronautics 2018年第7期31卷 1480-1488页

作者： Shubo YANG xi WANG Bei YANG Collaborative Innovation Center for Advanced Aero-Engine Beihang University School of Energy and Power Engineering Beihang University

In practice, some sensors of aircraft engines naturally fail to obtain an acceptable measurement for control propose, which will severely degrade the system performance and even deactivate the limit protection function. This paper proposes an adaptive strategy for the limit protection task under unreliable measurement. With the help of a nominal system, an online estimator with gradient adaption law and low-pass filter is devised to evaluate output *** on the estimation result, a sliding mode controller is designed by defining a sliding surface and deriving a control law. Using Lyapunov theorem, the stability of the online estimator and the closed-loop system is detailedly proven. Simulations based on a reliable turbofan model are presented, which verify the stability and effectiveness of the proposed method. Simulation results show that the online estimator can operate against the measurement noise, and the sliding controller can keep relevant outputs within their limits despite slow-response sensors.

关键词： Adaptive control Aircraft engine Estimators Protection Sliding mode control

基于技能人才培养的技工院校城市轨道交通专业课程体系建设

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时代汽车 2024年第16期 97-99页

作者：许曦俞家凯浙江交通技师学院运输管理学院浙江金华321000

随着城市化的进程,城市轨道交通逐渐成为城市公共交通的重要组成部分。现今许多大中城市纷纷建立起城市轨道交通体系,以促进和完善城市基本框架的建设。计算机、人工智能的出现,也促使城市轨道交通走向一个信息化、智能化的新发展方向,... 详细信息

随着城市化的进程,城市轨道交通逐渐成为城市公共交通的重要组成部分。现今许多大中城市纷纷建立起城市轨道交通体系,以促进和完善城市基本框架的建设。计算机、人工智能的出现,也促使城市轨道交通走向一个信息化、智能化的新发展方向,但同时城市轨道交通也面临着新的挑战。城市轨道交通体系由于其大体量、高运速、多维保的特性,企业对技能人才的专业技能和综合素质的要求也相对较高,高素质,强技能的人才更容易获得企业的青睐。

关键词：技能人才培养城市轨道交通课程体系建设

A generalized evidence distance

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Journal of Systems Engineering and Electronics 2016年第2期27卷 470-476页

作者： Hongming Mo xi Lu Yong Deng School of Computer and Information Science Southwest University Chongqing 400715 China Department of the Tibetan Language Sichuan University for Nationalities Kangding 626001 China School of Hanhong Southwest University Chongqing 400715 China

How to efficiently measure the distance between two basic probability assignments（BPAs） is an open issue. In this paper, a new method to measure the distance between two BPAs is proposed, based on two existing measures of evidence distance. The new proposed method is comprehensive and generalized. Numerical examples are used to illustrate the effectiveness of the proposed method.

关键词： Dempster-Shafer evidence(D-S) theory basic probability assignment(BPA) belief function evidence distance similarity function

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精彩豪情之美——沧州民间高跷服饰艺术研究

丝网印刷 2024年第3期 33-36页

作者：杨曦刘立军河北科技大学

高跷是沧州民间花会中较为典型的代表,演出服装与道具等具有典型的民间表演特征,一定程度上反映着当地的文化特色。文章以前李寨村高跷为案例样本,对其丰富的角色服装服饰艺术做了深入考察,呈现出沧州民间花会服饰的发展规律及艺术特色... 详细信息

高跷是沧州民间花会中较为典型的代表,演出服装与道具等具有典型的民间表演特征,一定程度上反映着当地的文化特色。文章以前李寨村高跷为案例样本,对其丰富的角色服装服饰艺术做了深入考察,呈现出沧州民间花会服饰的发展规律及艺术特色,以期为当代服饰及创新提供重要参考依据。

关键词：沧州花会李寨高跷服饰艺术创新