矿床灰色预测系统观     

徐忠祥  陈守余  吴国平 《地球学报》1996,17(Z1):207-214

矿床是在漫长的时间、广阔的空间、复杂的介质中，由一定的成矿作用形成，赋存于地质环境发生局部性变异的地区。这种异常变化可分为地理、地球物理、地球化学三大类。它们概有各自的特殊性，又有相经的关联性。人们采用地质、地球物理、地球化学勘探方法获提的找矿信息，可以将其视为成矿作用在3个侧面的表现形式。显然，用现代灰色系统思想来分析，长期、复杂、多源的成矿作用是灰色动态过程；综合方法寻找矿床是地质找矿灰色系统工程，矿床形成和分布是多种控矿地质因素综合作用、相互关联、发展变化的灰色系统。因此，从矿床的预测的意义上说，就是对这个系统进行整体上的考察，揭示灰色成矿场的展布，以圈定矿床赋存的最有利部位。 在新的矿床预测方法的研究中，我们把灰色系统理论与地质、物探、化探方法相结合，提出了以已知矿床上建立的参考数列系为灰色子波，对研究区的比较数列系进行关联度扫描，从中圈定关联度异常，预测矿床赋存部位的矿床灰色预测法。在新疆哈密研究区作了隐伏铜镍矿床预测试验，证实了该方法具有矿床信息提取、综合处理、靶区优选、定位预测的功能，适用于大比例尺隐伏矿床预测。  相似文献   

水稻耗水规律及节水灌溉技术的试验研究   总被引：1，自引：0，他引：1  

钱国萍  曹乃和  陆葆跃  周昌云  周新民  肖海涛 《气象》2002,28(7):22-25

根据18年的水稻耗水量试验资料，寻找水稻耗水量与光、温、水等气象要素的一般规律。在此基础上，考虑未来天气趋势和土壤性质的作用，确定水稻的灌溉量。该灌溉技术既满足水稻生理需求，又能达到节约用水，减小成本，夺取稳产高产的目的。  相似文献   

Discrete‐time variable structure control method for seismic‐excited building structures with time delay in control     

Guoping Cai  Jinzhi Huang 《地震工程与结构动力学》2002,31(7):1347-1359

The discrete‐time variable structure control method for seismically excited linear structures with time delay in control is investigated in this paper. The control system with time delay is first discretized and transformed into standard discrete form which contains no time delay in terms of the time delay being integer and non‐integer times of sampling period, respectively. Then the discrete switching surface is determined using ideal quasi‐sliding mode and discrete controller is designed using the discrete approach‐law reaching condition. The deduced controller and switching surface contain not only the current step of state feedback but also linear combination of some former steps of controls. Numerical simulations are illustrated to verify the feasibility and robustness of the proposed control method. Since time‐delay effect is incorporated in the mathematical model for the structural control system throughout the derivation of the proposed algorithm, system performance and dynamic stability are guaranteed. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

The Role of Local Knowledge in the Risk Management of Extreme Climates in Local Communities: A Case Study in a Nomadic NIAHS Site     

WANG Guoping  YANG Lun  LIU Moucheng  LI Zhidong  HE Siyuan  MIN Qingwen 《资源与生态学报(英文版)》2021,12(4):532-542

In the context of climate change, research on extreme climates and disaster risk management has become a crucial component of climate change adaptation. Local communities, which have been facing extreme climates for a long time in their production and daily life, have developed some locally applicable traditional knowledge that has played an important role in their adaptation to extreme climate and disaster risk management. Therefore, this research aims to link Local knowledge (LK) to community extreme climate disaster risk management in order to construct a conceptual model. It then takes the extreme climate adaptation strategy of traditional nomads in a temperate grassland of China as an example to analyze the role of LK in extreme climate adaptation using the proposed theoretical framework. The main research objectives of this study are: (1) To construct a conceptual model to illustrate the relations among extreme climate events, risk management, LK, and farmers' adaptation strategies; (2) To apply the theoretical framework to a field case to reveal context-specific extreme climate adaptation mechanisms with LK as a critical component; (3) To test the framework and provide suggestions for the extreme climates adaptation, and the conservation of LK related to climate change adaptation. The results show that from the perspective of disaster risk management, local communities could manage extreme climates as a disaster risk through adaptation strategies formed from LK, because as a knowledge system, LK contains relevant knowledge covering the whole process of disaster risk management.  相似文献   

中国资源型城市高质量发展综合评估及影响机理     

崔丹  卜晓燕  徐祯  李国平  吴殿廷 《地理学报》2021,76(10):2489-2503

促进资源型城市转型升级与高质量发展,是中国全面实现高质量发展的难点和重点.对资源型城市高质量发展水平进行综合评估并分析其影响机理既能丰富相关理论研究,也具有重要的实践意义.基于马克思主义政治经济学,梳理和分析了新时代高质量发展的理论框架,系统构建了资源型城市高质量发展的指标体系,在此基础上综合测算了中国117个资源型城市的高质量发展水平,并深入分析了其影响机理.结果表明:①2005-2017年资源型城市高质量发展水平持续增长,整体呈现显著的"东部相对较高、西部相对较低"的分布格局.②高质量发展水平较高和较低的城市具有明显的区域集聚特征,但高质量发展水平局部不平衡性加剧,空间极化现象持续扩大.③不同成长阶段的城市高质量发展水平存在较大差别,其中,再生型城市高质量发展水平最高,而衰退型城市高质量发展水平最低.④资源型城市与省会城市或直辖市的距离、区位和海拔、城市的开放时间等均对资源型城市高质量发展水平有重要影响.  相似文献   

北京市域制造业的空间演化特征     

刘霄泉  孙铁山  李国平 《地理研究》2018,37(8):1575-1586

北京市域制造业在结构调整的同时也在不断发生空间格局的变动。在京津冀协同发展战略的推进下,北京非首都功能疏解不断加速,将进一步加剧北京制造业产业结构的调整,进而影响空间格局的演化。利用2008年和2013年北京市经济普查数据中街道、镇乡的制造业大类的就业数据,从街乡的尺度,分析探讨北京市域内制造业的空间演化特征与趋势。研究显示：2008-2013年北京市制造业的产业结构和空间结构均趋向集聚,增长产业是制造业空间集聚的主导力量,在引导制造业空间进一步集聚的同时,形成了明晰的空间分异,增长产业更加趋向于在专门化程度更高的地区集聚,就重点街乡来看,北部地区的空间发展趋势将较为稳定,南部地区可能成为未来需要重点关注的高变动区域。  相似文献   

城市热岛强度的数值试验     

李国平  李东川 《成都信息工程学院学报》1993,(4)

本文从大气热力—动力学方程出发,导出形式较为简单的热岛分析解,通过数值试验,讨论了城市热岛强度与影响因子(如平均风速,城市加热量,摩擦效应和大气稳定度等)之间的关系。  相似文献   

青藏高原西部地表反射率的合成分析     

张鹏飞  李国平 《山地学报》2007,25(6):649-654

利用中(国)日(本)青藏高原陆面过程合作试验(GAME/Tibet)设立于青藏高原西部狮泉河和改则两地自动气象站(AW S)1997~1998年观测的大气、辐射和土壤等资料,计算了两地的逐时地表反射率,并进行了日平均、月平均和日合成分析,据此讨论了青藏高原西部地表反射率的若干变化特征,并在计算了对反射率影响最大的因子——太阳高度角的基础上,着重讨论了青藏高原西部地表反射率的日变化特征。结果表明:夏半年,由于降水使土壤湿度增大,植被生长、地表反射率值较低;冬半年,受土壤湿度减小、雪盖覆盖影响,地表反射率值较高,12月平均值可达0.5以上。而地表反射率的日变化特征表现为,清晨、黄昏地表反射率高,中午地表反射率低,大致呈U形曲线,与太阳高度角的变化相反。该工作有助于深入了解高原地区地表反射率的平均状况及其变化特征。  相似文献   

Diagenesis and Fluid Flow History in Sandstones of the Upper Permian Black Jack Formation, Gunnedah Basin, Eastern Australia          下载免费PDF全文

BAI Guoping John B. KEENE 《《地质学报》英文版》2007,81(3):433-441

The fluid flow history during diagenesis of sandstones in the Upper Permian Black Jack Formation of the Gunnedah Basin has been investigated through integrated petrographic observations, fluid inclusion investigations and stable isotope analyses. The early precipitation of mixed-layer illite/smectite, siderite, calcite, ankerite and kaolin proceeded at the presence of Late Permian connate meteoric waters at temperatures of up to 60℃. These evolved connate pore waters were also parental to quartz, which formed at temperatures of up to 87℃. The phase of maximum burial was characterized by development of filamentous illite and late calcite at temperatures of up to -90℃. Subsequent uplifting and cooling led to deep meteoric influx from surface, which in turn resulted in dissolution of labile grains and carbonate cements, and formation of second generation of kaolin. Dawsonite was the last diagenetic mineral precipitated and its formation is genetically related to deep-seated mamagtic sourced CO2.  相似文献   

地基GPS水汽资料在石家庄一次暴雨过程中的应用     

李国翠  李国平  连志鸾  仝美然  岳艳霞 《河南气象》2007,(3)

利用石家庄市地基GPS可降水量和逐时高时间分辨率地面气象资料,对2006年8月14日发生在石家庄地区的一次暴雨天气过程进行了分析。结果表明:此次暴雨发生前高能高湿,可降水量有一个缓慢积累过程;暴雨期间可降水量达最大,且可降水量极大值出现时间与降水强度吻合;降水结束后可降水量迅速下降。  相似文献