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Grouping response method for equivalent static wind loads based on a modified LRC method 被引量:9
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作者 Zhou Xuanyi Gu Ming Li Gang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2012年第1期107-119,共13页
Wind loading is one of the most important loads for controlling the design of large-span roof structures. Equivalent static wind loads, which can generally aim at determining a specific response, are widely used by st... Wind loading is one of the most important loads for controlling the design of large-span roof structures. Equivalent static wind loads, which can generally aim at determining a specific response, are widely used by structural designers. A method for equivalent static wind loads applicable to multi-responses is proposed in this paper. A modified load- response-correlation (LRC) method corresponding to a particular peak response is presented, and the similarity algorithm implemented for the group response is described. The main idea of the algorithm is that two responses can be put into one group if the value of one response is close to that of the other response, when the structure is subjected to equivalent static wind loads aiming at the other response. Based on the modified LRC, the grouping response method is put forward to construct equivalent static wind loading. This technique can simultaneously reproduce peak responses for some grouped responses. To verify its computational accuracy, the method is applied to an actual large-span roof structure. Calculation results show that when the similarity of responses in the same group is high, equivalent static wind loads with high accuracy and reasonable magnitude of equivalent static wind distribution can be achieved. 展开更多
关键词 large-span roof equivalent static wind loads modified LRC method grouping response similarityalgorithm
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UNFOLDING OF MULTIPARAMETER EQUIVARIANT BIFURCATION PROBLEMS WITH TWO GROUPS OF STATE VARIABLES UNDER LEFT-RIGHT EQUIVALENT GROUP 被引量:1
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作者 郭瑞芝 李养成 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第4期530-538,共9页
Based on the left_right equivalent relation of smooth map_germs in singularity theory, the unfoldings of multiparameter equivariant bifurcation problems with respect to left_right equivalence are discussed. The state ... Based on the left_right equivalent relation of smooth map_germs in singularity theory, the unfoldings of multiparameter equivariant bifurcation problems with respect to left_right equivalence are discussed. The state variables of such an equivariant bifurcation problem were divided into two groups, in which the first can vary independently, while the others depend on the first in the varying process. By applying related methods and techniques in the unfolding theory of smooth map_germs, the necessary and sufficient condition for an unfolding of a multiparameter equivariant bifurcation problem with two groups of state variables to be versal is obtained. 展开更多
关键词 equivariant bifurcation left_right equivalent group UNFOLDING
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Morita Equivalent Blocks in Subgroups of Finite Groups
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作者 YANG Qinqin FAN Yun 《Wuhan University Journal of Natural Sciences》 CAS 2006年第3期469-472,共4页
Let (K, O, k) be a p-modular system and G be a finite group. We prove that block A of RG and block B of RH are nalurally Morita equivalent of degree n if and only if A≌B+…+B}→n^2 as right R[H×H]-modules an... Let (K, O, k) be a p-modular system and G be a finite group. We prove that block A of RG and block B of RH are nalurally Morita equivalent of degree n if and only if A≌B+…+B}→n^2 as right R[H×H]-modules and A and B have the same defect(where R∈{k,O}), which is a generalization of the result of Külshammer Burkhard in a p-modular system for an arbitrary subgroup H of G. It is proved that naturally Morita equivalent blocks are equivalent blocks and Morita equivalent via a bimodule with trivial source. 展开更多
关键词 naturally Morita equivalence G-ALGEBRA defect pointed group source algebra
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Einstein’s Dark Energy via Similarity Equivalence, ‘tHooft Dimensional Regularization and Lie Symmetry Groups 被引量:4
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作者 Mohamed S. El Naschie 《International Journal of Astronomy and Astrophysics》 2016年第1期56-81,共26页
Realizing the physical reality of ‘tHooft’s self similar and dimensionaly regularized fractal-like spacetime as well as being inspired by a note worthy anecdote involving the great mathematician of Alexandria, Pytha... Realizing the physical reality of ‘tHooft’s self similar and dimensionaly regularized fractal-like spacetime as well as being inspired by a note worthy anecdote involving the great mathematician of Alexandria, Pythagoras and the larger than life man of theoretical physics Einstein, we utilize some deep mathematical connections between equivalence classes of equivalence relations and E-infinity theory quotient space. We started from the basic principles of self similarity which came to prominence in science with the advent of the modern theory of nonlinear dynamical systems, deterministic chaos and fractals. This fundamental logico-mathematical thread related to partially ordered sets is then applied to show how the classical Newton’s kinetic energy E = 1/2mv<sup>2</sup> leads to Einstein’s celebrated maximal energy equation E = mc<sup>2</sup> and how in turn this can be dissected into the ordinary energy density E(O) = mc<sup>2</sup>/22 and the dark energy density E(D) = mc<sup>2</sup>(21/22) of the cosmos where m is the mass;v is the velocity and c is the speed of light. The important role of the exceptional Lie symmetry groups and ‘tHooft-Veltman-Wilson dimensional regularization in fractal spacetime played in the above is also highlighted. The author hopes that the unusual character of the analysis and presentation of the present work may be taken in a positive vein as seriously attempting to propose a different and new way of doing theoretical physics by treating number theory, set theory, group theory, experimental physics as well as conventional theoretical physics on the same footing and letting all these diverse tools lead us to the answer of fundamental questions without fear of being labelled in one way or another. 展开更多
关键词 equivalence Relation SCALING Intermediate Asymptotic Golden Mean Scaling Einstein Self Similarity Fractal Scaling E-INFINITY Special Relativity Random Cantor Sets ‘tHooft Regularization Fractal Quantum Field Quantum Gravity Exceptional Lie Symmetry groups
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Equivalent comparison and analysis between different nominal frequencies
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作者 李智奇 韦中 +2 位作者 周渭 宋慧敏 鲁伟昊 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期238-241,共4页
We analyze the phenomena of phase group synchronization between the different nominal frequency signals and propose a new theory of the equivalent comparison between them. The exact expression of the equivalent compar... We analyze the phenomena of phase group synchronization between the different nominal frequency signals and propose a new theory of the equivalent comparison between them. The exact expression of the equivalent comparison is deduced. High resolution frequency measurement and phase comparison can be realized using this theory with the divider. For avoiding the frequency mixing, multiplication and synthesis, the system phase noise is improved and the higher resolution comparison and measurement are achieved between the different nominal frequencies by theory. 展开更多
关键词 phase difference group synchronization equivalent comparison frequency measurement
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The Tarski Theorems and Elementary Equivalence of Group Rings
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作者 Benjamin Fine Anthony Gaglione +1 位作者 Gerhard Rosenberger Dennis Spellman 《Advances in Pure Mathematics》 2017年第2期199-212,共14页
The Tarski theorems, proved by Myasnikov and Kharlampovich and inde-pendently by Sela say that all nonabelian free groups satisfy the same first-order or elementary theory. Kharlampovich and Myasnikov also prove that ... The Tarski theorems, proved by Myasnikov and Kharlampovich and inde-pendently by Sela say that all nonabelian free groups satisfy the same first-order or elementary theory. Kharlampovich and Myasnikov also prove that the elementary theory of free groups is decidable. For a group ring they have proved that the first-order theory (in the language of ring theory) is not decidable and have studied equations over group rings, especially for torsion-free hyperbolic groups. In this note we examine and survey extensions of Tarksi-like results to the collection of group rings and examine relationships between the universal and elementary theories of the corresponding groups and rings and the corresponding universal theory of the formed group ring. To accomplish this we introduce different first-order languages with equality whose model classes are respectively groups, rings and group rings. We prove that if R[G] is elementarily equivalent to S[H] then simultaneously the group G is elementarily equivalent to the group H and the ring R is elementarily equivalent to the ring S with respect to the appropriate languages. Further if G is universally equivalent to a nonabelian free group F and R is universally equivalent to the integers Z then R[G] is universally equivalent to Z[F] again with respect to an ap-propriate language. 展开更多
关键词 group RING ELEMENTARY equivalent Universally equivalent Direct UNION Discriminates
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The Equivalence of Certain Norms on the Heisenberg Group
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作者 Murphy E. Egwe 《Advances in Pure Mathematics》 2013年第6期576-578,共3页
Let IHn be the (2n+1)-dimensional Heisenberg group. In this paper, we shall give among other things, the properties of some homogeneous norms relative to dilations on the IHn and prove the equivalence of these norms.
关键词 HEISENBERG group HEISENBERG Norms equivalent Norms HOMOGENEOUS group
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Equivalence between Modulus of Smoothness and K-Functional on Rotation Group SO(3)
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作者 Zhuyuan Yang Zongwen Yang 《Journal of Applied Mathematics and Physics》 2017年第2期341-345,共5页
In this paper we obtain the equivalence between modulus of smoothness and K-functional on rotation group SO(3).
关键词 ROTATION group MODULUS of SMOOTHNESS K-FUNCTIONAL equivalENCE
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The Unitary Equivalence of Operators and K_0-Group of Commutant Algebras
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作者 何华 蒋春澜 《Northeastern Mathematical Journal》 CSCD 2001年第4期481-486,共6页
We show that two irreducible operators on H are unitari1y equivalentif and only if W*(A B)’≌M2(C), and give an answer to the open question posedby J. B. Conway (Subnormal Operators, πPitman, Advanced Publishing Pro... We show that two irreducible operators on H are unitari1y equivalentif and only if W*(A B)’≌M2(C), and give an answer to the open question posedby J. B. Conway (Subnormal Operators, πPitman, Advanced Publishing Program,Boston, London, Melbourne, 1981) for irreducible operator. We also show that ifT, T1 and T2 are irreducible operators with T T1≌T T2, then T1≌T2. Finally,weshow that K0 (A(D))≌Z, giving a new result on the K0-group of Banach algebras. 展开更多
关键词 irreducible operator unitary equivalence K0-group
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向量组等价的一个新定义——以三维向量为例
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作者 解顺强 《大学数学》 2026年第1期83-89,共7页
以三维向量为例,从两个线性方程组同解出发,给出了两个向量组等价的一种新定义,并证明了此定义与现有教材中的向量组等价的定义是等价的.此新定义将向量组等价与求解线性方程组紧密的联系起来,完善了用求解线性方程组将线性代数的几大理... 以三维向量为例,从两个线性方程组同解出发,给出了两个向量组等价的一种新定义,并证明了此定义与现有教材中的向量组等价的定义是等价的.此新定义将向量组等价与求解线性方程组紧密的联系起来,完善了用求解线性方程组将线性代数的几大理论(如矩阵、行列式、向量组、线性方程组)串联起来的线条,便于学生理解和掌握.同时也为抽象的向量组等价的概念找到了应用的背景. 展开更多
关键词 线性代数 线性方程组 向量组 等价
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On the Equal-height Elements of the Fuzzy Subgroups
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作者 张诚一 胡丽萍 党平安 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第2期82-85,共4页
The properties of the equal height elements of the fuzzy subroups and the classification of groups by its fuzzy subgroups are discussed.
关键词 group fuzzy subgroup equivalENCE equal height element
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基于等效时间递推与阶群算法的多阶段应力下产品可靠性评估
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作者 盛沛 肖支才 《装备环境工程》 2026年第1期130-136,共7页
目的 针对多阶段变应力环境下产品可靠性预测中变应力叠加效应难量化的问题,提出一种融合等效时间递推与阶群算法的可靠性评估方法。方法 通过等效时间递推将真实时间映射为等效老化时间,量化不同阶段应力对产品老化的叠加影响。采用阶... 目的 针对多阶段变应力环境下产品可靠性预测中变应力叠加效应难量化的问题,提出一种融合等效时间递推与阶群算法的可靠性评估方法。方法 通过等效时间递推将真实时间映射为等效老化时间,量化不同阶段应力对产品老化的叠加影响。采用阶群算法构建适应度函数,并迭代拟合威布尔参数。结果 以某产品三阶段寿命试验为例,威布尔参数误差较小,故障概率预测误差符合工程需求。结论 该方法可有效支撑多阶段应力场景下的产品可靠性评估,为产品寿命预测提供技术支持。 展开更多
关键词 多阶段应力 可靠性评估 等效时间递推 阶群算法 威布尔参数 故障概率预测
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Bloodletting puncture in the treatment of acute ischemic stroke:protocol for a mixed-method study of a multi-center randomized controlled trial and focus group 被引量:1
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作者 DAI Zeqi LIAO Xing +3 位作者 GUAN Yueyue ZENG Zixiu TANG Jun HU Jing 《Journal of Traditional Chinese Medicine》 SCIE CSCD 2023年第6期1259-1267,共9页
This study is to investigate the effectiveness and safety of bloodletting puncture(BP)for acute ischemic stroke(AIS)when used in combination with standard treatment,as well as the patients'feelings and attitudes t... This study is to investigate the effectiveness and safety of bloodletting puncture(BP)for acute ischemic stroke(AIS)when used in combination with standard treatment,as well as the patients'feelings and attitudes toward the treatment.This is a mixed method research which includes a multi-center,superiority,randomized controlled clinical trial,and focus group interview.A total of 360 AIS participants will be enrolled.They will be randomized into one of the following two groups for 7 d:(a)BP with standard treatment group(n=180);(b)standard treatment group(n=180).The primary outcome will be National Institute of Health stroke scale(NIHSS)score at day 7 after treatment.Secondary outcomes will be changes of Glasgow Coma Scale score,NIHSS score,mRS and Traditional Chinese Medicine syndrome score from baseline to 7,14,and 30 d after treatment,recurrence rate and all-cause mortality rate within 30 d,and the safety assessments.The focus group will be conducted with a purposive sample of 1-2 acupuncturists and 1-2 patients respectively at each center at 7 and 30 d after treatment.We designed a mixed method study to evaluate the effect of BP,an acupuncture therapy for patients with AIS.If the findings of this study confirm the effectiveness of BP to reduce the NIHSS score and other related outcomes and patients are willing to accept the therapy,we believe this study will help the implementation of this therapy in clinical practice,and provide new evidence for the treatment of AIS. 展开更多
关键词 BLOODLETTING PUNCTURES ischemic stroke equivalence trial randomized controlled trial focus groups clinical protocols
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Preliminary group classification of quasilinear third-order evolution equations
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作者 黄定江 张鸿庆 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第3期275-292,共18页
Group classification of quasilinear third-order evolution equations is given by using the classical infinitesimal Lie method, the technique of equivalence transformations, and the theory of classification of abstract ... Group classification of quasilinear third-order evolution equations is given by using the classical infinitesimal Lie method, the technique of equivalence transformations, and the theory of classification of abstract low-dimensional Lie algebras. We show that there are three equations admitting simple Lie algebras of dimension three. All non-equivalent equations admitting simple Lie algebras are nothing but these three. Furthermore, we also show that there exist two, five, twenty-nine and twenty-six non- equivalent third-order nonlinear evolution equations admitting one-, two-, three-, and four-dimensional solvable Lie algebras, respectively. 展开更多
关键词 quasilinear third-order evolution equations group classification classical infinitesimal Lie method equivalence transformation group abstract Lie algebras
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Symmetry groups and Gauss kernels of Schrdinger equations
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作者 Kang Jing Qu Chang-Zheng 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期66-75,共10页
The relationship between symmetries and Gauss kernels for the SchrSdinger equation iut = uxx + f(x)u is established. It is shown that if the Lie point symmetries of the equation are nontrivial, a classical integral... The relationship between symmetries and Gauss kernels for the SchrSdinger equation iut = uxx + f(x)u is established. It is shown that if the Lie point symmetries of the equation are nontrivial, a classical integral transformations of the Gauss kernels can be obtained. Then the Gauss kernels of Schroedinger equations are derived by inverting the integral transformations. Furthermore, the relationship between Gauss kernels for two equations related by an equivalence transformation is identified. 展开更多
关键词 Schroedinger equation symmetry group Gauss kernel equivalence transformation
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Lattice of Finite Group Actions on Prism Manifolds
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作者 John E. Kalliongis Ryo Ohashi 《Advances in Pure Mathematics》 2012年第3期149-168,共20页
The set of finite group actions (up to equivalence) which operate on a prism manifold M, preserve a Heegaard Klein bottle and have a fixed orbifold quotient type, form a partially ordered set. We describe the partial ... The set of finite group actions (up to equivalence) which operate on a prism manifold M, preserve a Heegaard Klein bottle and have a fixed orbifold quotient type, form a partially ordered set. We describe the partial ordering of these actions by relating them to certain sets of ordered pairs of integers. There are seven possible orbifold quotient types, and for any fixed quotient type we show that the partially ordered set is isomorphic to a union of distributive lattices of a certain type. We give necessary and sufficent conditions, for these partially ordered sets to be isomorphic and to be a union of Boolean algebras. 展开更多
关键词 Finite group Action PRISM 3-MANIFOLD equivalence of Actions ORBIFOLD Partially Ordered Set DISTRIBUTIVE LATTICE
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The Homotopical Proof of Π<sub>1</sub>(<i>S</i>, <i>x<sub>o</sub></i>) as a Fundamental Group in a General Interval
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作者 Zigli David Delali Obeng-Denteh William +1 位作者 Brew Lewis Ansah Richard Kwame 《Advances in Pure Mathematics》 2021年第5期377-385,共9页
The aim of this study is to establish that, the equivalent class <img src="Edit_d35dd794-39a5-4ce4-992b-5130559b3c82.png" width="70" height="22" alt="" /> which is made up... The aim of this study is to establish that, the equivalent class <img src="Edit_d35dd794-39a5-4ce4-992b-5130559b3c82.png" width="70" height="22" alt="" /> which is made up of homotopic loops is a group with respect to <img src="Edit_3577ec7c-e6f5-4d71-8bd5-c63ea8fdb24f.png" width="30" height="15" alt="" /> in the general interval <span style="white-space:nowrap;">[m,n]. The study proved from homotopical point of view that <img src="Edit_4cb511c3-e469-47e3-bd9c-e971594f939c.png" width="70" height="22" alt="" /> is associative, has an identity and inverse function. The study established with proof that <img src="Edit_39497a4b-b0e9-40d9-8f31-49816e760d6a.png" width="70" height="22" alt="" /> is a fundamental group in <span style="white-space:nowrap;">[m,n] ,<img src="Edit_077b19f1-afb3-41f5-8d39-df073165c9dc.png" width="75" height="18" alt="" />. 展开更多
关键词 HOMOTOPY Fundamental group HOMEOMORPHISM equivalent Class Path Concatenation
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EQUIVARIANT SELF EQUIVALENCES OF PRINCIPAL FIBRE BUNDLES
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作者 XIA JIANGUO 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1998年第1期109-116,共8页
Let E be a compact Lie group, G a closed subgroup of E, and H a closed normal subgroup of G . For principal fibre bundle (E,p, E/G;G) and (E/H,p′,E/G;G/H), the relation between aut G(E) ... Let E be a compact Lie group, G a closed subgroup of E, and H a closed normal subgroup of G . For principal fibre bundle (E,p, E/G;G) and (E/H,p′,E/G;G/H), the relation between aut G(E) (resp. aut * G(E) ) and aut G/H (E/H) (resp.aut * G/H (E/H)) is investigated by using bundle map theory and transformation group theory. It will enable us to compute the group F G(E) (resp. E G(E)) while the group F G/H (E/H) is known. 展开更多
关键词 G space space of equivariant self homotopy equivalences group of equivariant self equivalences G fibration.
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初论矿床动态技术经济评价 被引量:1
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作者 陈景河 王京彬 +1 位作者 刘金辉 和志军 《矿床地质》 北大核心 2025年第2期259-278,共20页
市场是确定“矿与非矿”的基本准则。矿床具有地质、经济和环境三重属性,并随着市场和技术条件的变化而改变,需要对矿床开展动态的技术经济评价。文章以紫金矿业集团股份有限公司的实践案例为基础,探讨了基于“矿石流五环模型”的矿床... 市场是确定“矿与非矿”的基本准则。矿床具有地质、经济和环境三重属性,并随着市场和技术条件的变化而改变,需要对矿床开展动态的技术经济评价。文章以紫金矿业集团股份有限公司的实践案例为基础,探讨了基于“矿石流五环模型”的矿床技术经济动态评价的原理和方法。该模型以最大化利用资源为原则,以矿石流为走向,对地质、采矿、选矿、冶炼和环保5个环节统筹研究和全流程优化,通过不断降低生产成本,进而降低圈矿的边界品位,把大量过去不经济的矿化岩石转化为工业矿石,实现资源大幅增长和经济社会效益的最大化。采选冶环的成本决定了资源价值,以生产成本和边界品位为主要参数,初步构建了基于“矿石流五环模型”的矿床动态技术经济评价方法框架,包括矿床的自然禀赋特征(品位-吨位模型)、成本与边界品位经济评价的全流程模式、边界品位与资源精细管理、当量边界品位和净冶炼收益(NSR)边界品位评价方法等,当量品位是多金属矿床评价中极为重要的指标。以“矿石流五环模型”为指导,通过补充勘查和动态评价,福建紫金山金铜矿床由一个资源储量仅5.45 t的中小型金矿床,扩大为316 t的特大型金矿床,累计产金208 t,累计实现利润225亿元;西藏巨龙铜矿查明铜资源量(金属量),由原来的1027万吨扩大到2588万吨,新增的铜、钼、银资源量分别是原来的2.5倍、2.9倍和2.3倍,铜储量则从392万吨增加到1734万吨,是原储量的4.4倍,矿山开发经济和社会效益显著。 展开更多
关键词 矿床技术经济评价 矿石流五环模型 边界品位 当量品位 紫金矿业
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