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Models of Spatial Structures of Regional Multi-element Geochemical Anomalies over Copper-Polymetallic Orefields

Acta Geologica Sinica(English Edition) 2003年第1期77卷 72-80页

作者： SHI Changyi and ZHANG Jinhua China University of Geosciences, Beijing 100083 Institute of Geophysical and Geochemical Exploration, langfang Hebei 065000 China Univ Geosci Beijing 100083 Peoples R China Inst Geophys & Geochem Explorat Langfang 065000 Hebei Peoples R China

Regional stream sediment surveys at a 1:200,000 scale reveal positive andnegative regional multi-element geochemical anomalies over medium to large copper-polymetallicorefields of different genetic types in China. Regional geochemical anomalies of orefield refer tothose geochemical anomalies that are related to metallogenesis of an orefield in a certain area. Theanomaly area is typically 10 to 100 km^2. The regional multi-element anomalies related tomineralization can be divided into three groups, that is, the ore-element anomaly association,indicator element anomaly association, and metallogenic environmental element anomaly *** common spatial distributions over ore deposits or orefields possess unique structures. Themodel of spatial structure of regional multi-element geochemical anomalies (RAGSS) of an orefielddelineates structural feature possessed by orderly spatial distributions of different groups ofmulti-element anomaly associations related to orefield metallogenesis. It is used to outline thecommon metallogenetic anomaly visage that is composed of the orderly spatial distribution ofdifferent groups of multi-element anomaly associations. The orderly spatial distribution ofmulti-element anomalies over an orefield reflects element distributions as they are changed from adispersed 'out-of-order' state into a concentrated 'orderly' state during the mineralization of anorefield. Three different patterns of the spatial anomaly structure related to mineralization in anorefield can be concluded: (1) nested pattern; (2) eccentric pattern and; (3) peripheral *** are marked differences between multi-element anomaly patterns related and not related tomineralization. RAGSS models of orefields can be used to better understand and evaluate regionalmulti-element anomalies and identify ore types.

关键词： orefield regional geochemical anomaly model anomaly structure RAGSSmodel

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Bifurcation analysis in single-species population model with delay

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Science China Mathematics 2010年第6期53卷 1475-1481页

作者： JIANG ZhiChao & ZHANG WenZhi Fundamental Science Department,North China Institute of Astronautic Engineering,langfang 065000,China Fundamental Science Department North China Institute of Astronautic Engineering Langfang China

A single-species population model is investigated in this ***,we study the existence of Hopf bifurcation at the positive ***,an explicit algorithm for determining the direction of the Hopf bifurcation and stability of the bifurcation periodic solutions are derived by using the normal form and the center manifold *** last,numerical simulations to support the analytical conclusions are carried out.

关键词： Hopf bifurcation stability time delay numerical simulations

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Erentaolegai silver deposit in Inner Mongolia as an example of epithermal deposit

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Chinese Science Bulletin 1999年第S2期44卷 25-27页

作者： CHEN Xiang and XIAO Li Gold Geological Institute of State Economic and Trade Commission, langfang 065000, China Gold Geological Institute of State Economic and Trade Commission Langfang 065000 China

1 Comparison with the characteristics of geology and geochemistry of typical epithermal silverdeposit Erentaolegai silver deposit is located to the west bank of Kelulun river in the Xibarhuyou Banner,south-west of Manzhouli. The geotectonic is the joint of Hailar basin and Manzhouli-Xinbarhuyou Banner’svolcanic mole track. The stratas in the mining area are upper Jurassic Tamolangou formation andShangkuli formation: the former consists of andesite mainly and the latter is divided into three parts fromtop to bottom, namely rhyolite, decite, trachyte. The types of igeous rock in the mining area are graniteand quartz porphyry, both with age (120 ±6) Ma as determined by the Rb-Sr isochron. The principalstructures in the mining areas are faults, trending SN, NW, NE, mainly SN. The ore bodies are controlledby faults. It is a large-scale silver deposit found recently. Many years’ research shows that it is a silverepithermal deposit. Table 1 lists a comparison with the typical silver epithermal deposits.

关键词： Erentaolegai silver deposit epithermal deposit Inner Monguolia

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The Impression of langfang

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海外英语 2012年第7X期 196-196,229页

作者： LI Yang(langfang Urban Planning Exhibition Hall,langfang 065000,China) langfang Urban Planning Exhibition Hall Langfang 065000 China

langfang is located in the middle of Hebei province;it lies between the Bohai Sea to the east and the capital city of the country to the west,and lies between the Yan Mountain to the north and a large area of fertile plain soil to the *** is less than 50km from langfang to Beijing and takes less than an hour to the *** piece of land,interdependent with Beijing-Tianjin,is like a bright pearl,proudly embedded in the Beijing-Tianjin corridor.

关键词： position advantage history present future

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网络环境下公开军事情报的收集途径研究

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图书馆工作与研究 2008年第11期 43-45页

作者：赵科廊坊武警学院图书馆

随着计算机与通讯技术的发展,网络信息剧增,并以海量的形式分布在网络中,其中蕴含着若干公开军事情报,但由于网络信息的分散性、无序性、多样性、时效性以及不确定性等因素的存在,加之军事情报本身的特点,给查找公开军事情报带来了很大... 详细信息

随着计算机与通讯技术的发展,网络信息剧增,并以海量的形式分布在网络中,其中蕴含着若干公开军事情报,但由于网络信息的分散性、无序性、多样性、时效性以及不确定性等因素的存在,加之军事情报本身的特点,给查找公开军事情报带来了很大难度。本文根据网络环境下公开军事情报的特点,提出了公开军事情报要坚持的收集原则和利用途径。

关键词：网络环境军事情报收集

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The Significance of Remote Sensing Technology in Gold Ore Exploration in Huma District, Heilongjiang Province, China

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Global Geology 1999年第2期4卷 230-234页

作者： Liu Yinchun and Liu Zhijie (Gold geological institute of MMI,langfang,065000)

The methods of processing remote sensing image in forest area has been put forwa rd. With infrared waveband and organism geochemical remote sensing technology, w e extracted anomalous information related to gold ore in vegetated area and esta blished signs of interpreting remote sensing geological structures, Fur thermore, we have interpreted 4 sets of liner structure, more than 100 circular structures and a large circular block structure. Three evolutional stages of tec tonic stress fields have been divided. NE-NNE,NW and EW trending tructures cros s cut each other, comprising the basic structural pattern. Large circuar block str ucture with surrounding circular structure and the“corner area” of rhombus st ructure are usually the areas with gold mineralization.

关键词： vegetated area remote sensing gold deposit

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The existence spectrum for overlarge sets of pure directed triple systems

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Science China Mathematics 2010年第10期53卷 2801-2810页

作者： LIU YuanYuan1 & KANG QingDe2,1Department of Fundamental Science,North China Institute of Aerospace Engineering,langfang 065000,China 2Institute of Mathematics,Hebei Normal University,Shijiazhuang 050016,China Department of Fundamental Science North China Institute of Aerospace Engineering Langfang China Institute of Mathematics Hebei Normal University Shijiazhuang China

A directed triple system of order v,denoted by DTS(v),is a pair (X,B) where X is a v-set and B is a collection of transitive triples on X such that every ordered pair of X belongs to exactly one triple of B.A DTS(v) (X,A) is called pure and denoted by PDTS(v) if (a,b,c) ∈ A implies (c,b,a) ∈/ *** overlarge set of PDTS(v),denoted by OLPDTS(v),is a collection {(Y \{yi},Aij) : yi ∈ Y,j ∈ Z3},where Y is a (v+1)-set,each (Y \{yi},Aij) is a PDTS(v) and these Ais form a partition of all transitive triples on Y .In this paper,we shall discuss the existence problem of OLPDTS(v) and give the following conclusion: there exists an OLPDTS(v) if and only if v ≡ 0,1 (mod 3) and v > 3.

关键词： overlarge set pure directed triple system directed candelabra system

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Design and Implementation of Remote Buffer Overflow and Implanted Backdoor

Design and Implementation of Remote Buffer Overflow and Impl...

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2012 National Conference on Information Technology and Computer Science

作者： Xin Zhang langfang professional technology institute computer science and engineering department,langfang,HeBei 065000,China HaiYan Liu Computer science and engineering department,North china institute of aerospace engineering langfang,HeBei 065000,China

Network security research focused content is a buffer *** is a technology used by hackers *** paper,based buffer overflow,given the use of the remote overflow implanted backdoor design,and implementation *** this paper,introduce the detailed steps to structure Shellcode,as well as the specific implementation of the ***,gives remote overflow prevention recommendations.

关键词： Remote buffer overflow Shellcode Implanted Backdoor

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