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| 1 | 内蒙古中部四子王旗大庙岩体时代及成因显示文摘华北北缘的内蒙古中部地区出露大量晚古生代-早中生代花岗岩类,在空间上构成一条巨大的东西向花岗岩带。四子王旗大庙岩体作为一个典型的代表,以花岗闪长岩为主,其内部普遍发育暗色微粒包体(MMEs),是认识花岗岩岩石成因和演化的关键。本文对包体及寄主岩进行了同位素测年、岩相学、矿物化学、全岩主量元素和微量元素分析。寄主岩石中的锆石LA-ICPMS U-Pb年龄平均为265±7Ma(2σ),包体中单颗粒黑云母Rb-Sr年龄为253±5Ma(MSWD=0.85),属晚二叠世-早三叠世岩浆活动的产物。包体具塑性外形及岩浆结构,存在多种不平衡矿物组合;MME中的斜长石An组分及黑云母斑晶中MgO成分呈多期震荡,同时总体上均显示出幔部高于核、边部的特征,暗示斑晶可能为围岩捕虏晶,这种相似的成分变化指示包体与寄主岩相互作用引起的结晶环境改变,标志着岩浆成分的变化,是岩浆混合的标志之一;主量和微量数据进一步证明岩体的岩浆混合成因。Rb/Sr-K/Rb变化关系反映包体非结晶分异或黑云母堆晶的产物,而Ce/Pb-Ce、Ba-δEU和P_2O_5-δEu图及其他微量元素比值图等均表明花岗闪长岩体发生了岩浆混合作用,这也得到岩浆物理化学条件的支持。岩浆底侵和岩浆混合作用是该区岩体形成的主要机制和方式。岩石地球化学特征表明该岩体不同于加厚地壳和俯冲洋壳熔融的TTG和埃达克质岩石,而黑云母矿物化学和岩石地球化学显示其构造背景很可能为同碰撞环境。 | 章永梅 张华锋 刘文灿 周志广 | 2009 | 岩石学报2009，25，12： | 63 |
| 2 | 电子商务与中国企业出口行为:基于世界银行微观数据的分析显示文摘本文基于异质性企业垄断竞争模型的分析表明,电子商务提高了企业参与出口的可能性和企业出口密集度,即促进了企业出口扩展边际以及集约边际出口增长,而电子商务的贸易促进作用与企业生产效率正相关。本文基于世界银行中国企业调查数据,利用Probit以及Fractional Probit计量方法对理论模型推出的相关命题进行了检验,并用广义倾向得分匹配法(GPSM)对可能存在的内生性问题加以控制。经验研究结果支持了相关命题,即电子商务在出口可能性与出口密集度两个维度上,对贸易产生了显著的促进作用,虽然本文的结论也支持低效率企业出口的'生产率悖论'现象,但发现电子商务在边际上缓解了这种悖论。分不同规模和所有制样本的经验研究比较发现,电子商务的发展对大规模企业促进作用大于小规模企业、外资企业大于内资企业、民营企业大于国有企业。 | 茹玉骢 李燕 | 2014 | 国际贸易问题2014，0，12： | 43 |
| 3 | Characterization for commutators of n-dimensional fractional Hardy operators显示文摘In this paper, it was proved that the commutator Hβ,b generated by an n-dimensional fractional Hardy operator and a locally integrable function b is bounded from Lp1(Rn) to Lp2 (Rn) if and only if b is a C(M)O(Rn) function, where 1/p1 - 1/p2 = β/n, 1 < p1 <∞, 0 ≤β< n. Furthemore,the characterization of Hβ,b on the homogenous Herz space (K)qα,p(Rn) was obtained. | Zun-wei FU~(1,2) Zong-guang LIU~3 Shan-zhen LU~(1+) Hong-bin WANG~3 ~1 School of Mathematical Sciences,Beijing Normal University,Beijing 100875,China ~2 Department of Mathematics,Linyi Normal University,Linyi 276005,China ~3 Department of Mathematics,China University of Mining and Technology (Beijing),Beijing 100083,China | 2007 | Science China Mathematics2007，50，10： | 39 |
| 4 | Diagnostic accuracy of a deep learning approach to calculate FFR from coronary CT angiography显示文摘Background The computational fluid dynamics(CFD)approach has been frequently applied to compute the fractional flow reserve(FFR)using computed tomography angiography(CTA).This technique is efficient.We developed the DEEPVESSEL-FFR platform using the emerging deep learning technique to calculate the FFR value out of CTA images in five minutes.This study is to evaluate the DEEPVESSEL-FFR platform using the emerging deep learning technique to calculate the FFR value from CTA images as an efficient method.Methods A single-center,prospective study was conducted and 63 patients were enrolled for the evaluation of the diagnostic performance of DEEPVESSEL-FFR.Automatic quantification method for the three-dimensional coronary arterial geometry and the deep learning based prediction of FFR were developed to assess the ischemic risk of the stenotic coronary arteries.Diagnostic performance of the DEEPVESSEL-FFR was assessed by using wire-based FFR as reference standard.The primary evaluation factor was defined by using the area under receiver-operation characteristics curve(AUC)analysis.Results For per-patient level,taking the cut-off value<0.8 referring to the FFR measurement,DEEPVESSEL-FFR presented higher diagnostic performance in determining ischemia-related lesions with area under the curve of 0.928 compare to CTA stenotic severity 0.664.DEEPVESSEL-FFR correlated with FFR(R=0.686,P<0.001),with a mean di&ference of-0.006士0.0091(P=0.619).The secondary evaluation factors,indicating per vessel accuracy,sensitivity,specificity,positive predictive value,and negative predictive value were 87.3%,97.14%,75%,82.93%,and 95.45%,respectively.Conclusion DEEPVESSEL-FFR is a novel method that allows efficient assessment of the functional significance of coronary stenosis. | Zhi-Qiang WANG Yu-Jie ZHOU Ying-Xin ZHAO Dong-Mei SHI Yu-Yang LIU Wei LIU Xiao-Li LIU Yue-Ping LI | 2019 | Journal of Geriatric Cardiology2019，16，1： | 37 |
| 5 | 基于短时分数阶傅里叶变换的时频分析方法显示文摘本文研究了短时分数阶傅里叶变换(STFRFT)时频分析方法的分辨率精度和算法性能.首先,文中给出了一种STFRFT时频分辨率的数学计算表达式,其有利于时频分辨率的量化比较,仿真结果表明该理论量化值与观察值基本吻合;其次,针对算法运算量大的问题,提出了一种STFRFT的快速计算方法,它较传统的穷举搜索方法运算量约降低1个数量级;最后,给出了算法估计误差的理论分析并运用该方法对多目标信号进行了分析,仿真表明该方法可有效抑制交叉项和解决多分量时频信号的分离问题. | 庞存锁 刘磊 单涛 | 2014 | 电子学报2014，42，2： | 33 |
| 6 | Representation of the constitutive equation of viscoelastic materials by the generalized fractional element networks and its generalized solutions显示文摘The generalized fractional element networks are presented in this paper. In order to extend the structure of the model solutions to the generalized function space and make it contain more physical meanings, the restriction on the parameters of the fractional element proposed by Schiessel et al. is eliminated and a 'compatibility equation' is added. The discretization method for solving the inverse Laplace transform is used and developed. The generalized solutions of the model equations are given. At the same time the generalized fractional element network--Zener and Poyinting-Thomson models are discussed in detail. It is shown that all the results obtained previously about the models of single parameter with fractional order and the classical models with integer order can be contained as the special cases of the results of this paper. | 徐明瑜 谭文长 | 2003 | Science China(Physics,Mechanics & Astronomy)2003，46，2： | 25 |
| 7 | Weighted Boundedness for a Class of Rough Multilinear Operators | Yong DING Shan Zhen LU Department of Mathematics,Beijing Normal University,Beijing 100875,P.R.China E-mail:dingy@bnu.edu.cn lusz@bnu.edn.cn | 2001 | Acta Mathematica Sinica,English Series2001，17，3： | 24 |
| 8 | 金川Ⅰ号岩体橄榄石Ni-MgO相互关系及其地质意义显示文摘金川超镁铁质岩体赋存着仅次于加拿大Sudbury和俄罗斯Noril'sk-Talnakh的世界第三大在采铜镍硫化物矿床,岩体以一系列的NE向断层为界分成四个小岩体,由西至东依次为:Ⅲ、Ⅰ、Ⅱ、Ⅳ岩体。Ⅰ号岩体主要由二辉橄榄岩、含辉橄榄岩和橄榄二辉岩构成,橄榄石在各岩相中均为保存较好的主要造岩矿物。本文研究得到金川Ⅰ号岩体上部二辉橄榄岩和含辉橄榄岩中橄榄石的镁橄榄石Fo值介于83.9~85.7,而其Ni含量为1396×10^(-6)~2043×10^(-6),大多低于从S不饱和玄武岩浆中结晶出采的橄榄石的Ni含量。模拟计算结果表明橄榄石较低的Ni含量是因为橄榄石结晶的同时,发生了强烈的硫化物熔离;橄榄石的Fo-Ni关系还因与晶间硅酸盐熔浆的物质交换而发生改变。模拟计算还证明大约有30%的晶间硅酸盐岩浆与橄榄石发生Fe-Mg物质交换反应,导致早结晶橄榄石的Fo值减少了1~1.5。同时,橄榄石较小的Fo值变化表明,在橄榄石结晶和硫化物熔离过程中,不断有新的岩浆贯入和补充。 | 陈列锰 宋谢炎 Danyushevsky LV 肖加飞 李士彬 官建祥 | 2009 | 岩石学报2009，25，12： | 22 |
| 9 | Continuity of Higher Order Commutators on Certain Hardy Spaces | DING Yong LU Shan Zhen Department of Mathematics,Beijing Normal University,Beijing 100875.P.R.China E-mail:dingy@bnu.edu.cn lusz@bnu.edu.cnZHANG Pu Department of Mathematics.Zhejiang University(at Xixi Campus).Hangzhou 310028,P.R.China,E-mail:zhpjj@263,net | 2002 | Acta Mathematica Sinica,English Series2002，18，2： | 21 |
| 10 | PLANE SURFACE SUDDENLY SET IN MOTION IN A VISCOELASTIC FLUID WITH FRACTIONAL MAXWELL MODEL显示文摘The fractional calculus approach in the constitutive relationshipmodel of viscoelastic fluid is introduced.The flow near a wall suddenly set in mo-tion is studied for a non-Newtonian viscoelastic fluid with the fractional Maxwellmodel.Exact solutions of velocity and stress are obtained by using the discrete in-verse Laplace transform of the sequential fractional derivatives.It is found that theeffect of the fractional orders in the constitutive relationship on the flow field is signif-icant.The results show that for small times there are appreciable viscoelastic effectson the shear stress at the plate,for large times the viscoelastic effects become weak. | 谭文长 徐明瑜 | 2002 | Acta Mechanica Sinica2002，18，4： | 19 |
| 11 | An exact solution of unsteady Couette flow of generalized second grade fluid显示文摘The fractional calculus approach is introduced into the rheological constitutive model of a generalized second grade fluid. A constitutive model with fractional derivative is developed for the generalized second grade fluid. Unsteady Couette flow of the generalized second grade fluid is studied by using the method of the discrete inverse Laplace transform and generalized Mittag-Leffler function. And then an exact solution is obtained for this problem with arbitrary fractional derivative. This provides a new analytical tool for the study of viscoelastic fluid mechanics. | TAN Wenchang XIAN Feng WEI Lan | 2002 | Chinese Science Bulletin2002，47，21： | 17 |
| 12 | Determining the Optimal Solution Set for Linear Fractional Programming显示文摘The structure of the optimal solution set is derived for linear fractional programming with the representation theorem of polyhedral sets. Based on an adaptation of the convex simplex method credited to Gilmore and Gomory, we give the uniqueness condition of optimal solution and the computational procedures to find all optimal solutions if the uniqueness condition is not satisfied. Finally, an illustrative example is also given. | Xue Shengjia Management College, Jinan University,Guangzhou 510632, P.R. China | 2002 | Journal of Systems Engineering and Electronics2002，13，3： | 15 |
| 13 | Intermediate processes and critical phenomena: Theory, method and progress of fractional operators and their applications to modern mechanics显示文摘From point of view of physics, especially of mechanics, we briefly introduce fractional operators (with emphasis on fractional calculus and fractional differential equa- tions) used for describing intermediate processes and critical phenomena in physics and mechanics, their progress in theory and methods and their applications to modern me- chanics. Some authors’ researches in this area in recent years are included. Finally, prospects and evaluation for this subject are made. | XU Mingyu1 & TAN Wenchang2 1. Institute of Applied Mathematics, School of Math & System Science, Shandong University, Jinan 250100, China 2. State Key Laboratory of Turbulence and Complex Systems & Department of Mechanics and Engineering Science, Peking University, Beijing 100871, China | 2006 | Science China(Physics,Mechanics & Astronomy)2006，49，3： | 15 |
| 14 | Exact solutions for the flow of non-Newtonian fluid with fractional derivative in an annular pipe显示文摘This paper deals with some unsteady unidirectional transient flows of Oldroyd-B fluid in an annular pipe. The fractional calculus approach in the constitutive relationship model Oldroyd-B fluid is introduced and a generalized Jeffreys model with the fractional calculus has been built. Exact solutions of some unsteady flows of Oldroyd-B fluid in an annular pipe are obtained by using Hankel transform and Laplace transform for fractional calculus. The following four problems have been studied: (1) Poiseuille flow due to a constant pressure gradient; (2) axial Couette flow in an annulus; (3) axial Couette flow in an annulus due to a longitudinal constant shear; (4) Poiseuille flow due to a constant pressure gradient and a longitudinal constant shear. The well-known solutions for Navier-Stokes fluid, as well as those corresponding to a Maxwell fluid and a second grade one, appear as limited cases of our solutions. | TONG Dengke WANG Ruihe YANG Heshan | 2005 | Science China(Physics,Mechanics & Astronomy)2005，48，4： | 15 |
| 15 | Seismic analysis of structures with a fractional derivative model of viscoelastic dampers显示文摘Viscoelastic dampers are now among some of the preferred energy dissipation devices used for passive seismic response control. To evaluate the performance of structures installed with viscoelastic dampers, different analytical models have been used to characterize their dynamic force deformation characteristics. The fractional derivative models have received favorable attention as they can capture the frequency dependence of the material stiffness and damping properties observed in the tests very well. However, accurate analytical procedures are needed to calculate the response of structures with such damper models. This paper presents a modal analysis approach, similar to that used for the analysis of linear systems, for solving the equations of motion with fractional derivative terms for arbitrary forcing functions such as those caused by earthquake induced ground motions. The uncoupled modal equations still have fractional derivatives, but can be solved by numerical or analytical procedures. Both numerical and analytical procedures are formulated. These procedures are then used to calculate the dynamic response of a multi-degree of freedom shear beam structure excited by ground motions.Numerical results demonstrating the response reducing effect of viscoelastic dampers are also presented. | Tsu-sheng Chang Mahendra P.Singh | 2002 | Earthquake Engineering and Engineering Vibration2002，1，2： | 14 |
| 16 | 新疆哈尔里克山二叠纪碱性花岗岩-石英正长岩组合的成因及其构造意义显示文摘哈尔里克奥姆尔塔格碱性花岗岩(OMAG)侵入于小铺东二长花岗岩中。该岩体岩性较均一,呈灰紫色,主要矿物组合为石英、钾长石、钠长石、碱性角闪石和霓石;化学成分上富硅、碱,贫钙、镁,低铝;富Rb、Th、U和Zr,Ga/Al比值大(3.18×10~4~3.56×10~4),贫Ba、Sr,岩石中Co、Cr、V和Ni等过渡元素显著亏损,U、Hf、Zr和Nb等高场强元素的含量高;稀土总量较高,配分模式右倾,并具有显著的负铕异常;LA-ICP-MS锆石^(206)Pb/^(238)U加权平均年龄为287.6±2.1Ma;具有正的ε_(Nd)(t)值(+4.96),较低的(^(87)Sr/^(86)Sr),值(0.70159)。同样侵入于小铺东二长花岗岩中的恰干昆多沟含角闪石石英正长岩(QGQS)也呈灰紫色,其结构和构造与OMAG非常相似。两个岩体在主量元素和REE图解上均呈现有规律的分布和一致的演化趋势。从QGQS到OMAG,SiO_2含量增加(从64.71%~64.83%到71.23%~74.31%)、全碱含量降低(从11.72%~11.79%到8.49%~9.87%)和Al_2O_3含量减少(从16.09%~16.19%到11.44%~13.34%)、稀土总量减少(从592.3×10^(-6)~656.0×10^(-6)到273.9×10^(-6)~405.9×10^(-6))、轻/重稀土比值降低(从18.2~20.1到4.4~6.0)、稀土配分曲线从平滑到Eu显著亏损。基于OMAG的岩相学、矿物学、地球化学、锆石年代学和与QGQS的对比研究,笔者认为奥姆尔塔格碱性花岗岩可能是由石英正长岩母岩浆经过分离结晶作用演化的产物,且这种石英正长岩岩浆起源于亏损地幔;根据哈尔里克造山带地质演化历史的分析,这两个岩体均形成于紧随主碰撞后的挤压-伸展转折阶段。 | 汪传胜 顾连兴 张遵忠 吴昌志 唐俊华 三金柱 黎广荣 李中华 | 2009 | 岩石学报2009，25，12： | 14 |
| 17 | Myocardial ischemia is a key factor in the management of stable coronary artery disease显示文摘Previous studies demonstrated that coronary revascularization,especially percutaneous coronary intervention(PCI),does not significantly decrease the incidence of cardiac death or myocardial infarction in patients with stable coronary artery disease.Many studies using myocardial perfusion imaging(MPI) showed that,for patients with moderate to severe ischemia,revascularization is the preferred therapy for survival benefit,whereas for patients with no to mild ischemia,medical therapy is the main choice,and revascularization is associated with increased mortality.There is some evidence that revascularization in patients with no or mild ischemia is likely to result in worsened ischemia,which is associated with increased mortality.Studies using fractional flow reserve(FFR) demonstrate that ischemia-guided PCI is superior to angiography-guided PCI,and the presence of ischemia is the key to decisionmaking for PCI.Complementary use of noninvasive MPI and invasive FFR would be important to compensate for each method's limitations.Recent studies of appropriateness criteria showed that,although PCI in the acute setting and coronary bypass surgery are properly performed in most patients,PCI in the non-acute set-ting is often inappropriate,and stress testing to identify myocardial ischemia is performed in less than half of patients.Also,some studies suggested that revascularization in an inappropriate setting is not associated with improved prognosis.Taken together,the presence and the extent of myocardial ischemia is a key factor in the management of patients with stable coronary artery disease,and coronary revascularization in the absence of myocardial ischemia is associated with worsened prognosis. | Kohichiro Iwasaki | 2014 | World Journal of Cardiology2014，6，4： | 13 |
| 18 | 青藏高原北部新生代走构油茶错、纳丁错火山岩年代学、地球化学特征及其构造意义显示文摘本文对分布于藏北南羌塘地区的走构油茶错和纳丁错新生代火山岩进行了岩石学、同位素年代学和地球化学研究。两个地区火山岩主要由粗面玄武岩、橄榄粗安岩、安粗岩及粗面岩组成,具有从碱性系列火山岩到高钾钙碱性火山岩连续演化的特征。锆石U-Pb定年表明两个地区火山岩形成时代分别为34.64±0.55Ma和35.03±0.54Ma,另外在走构油茶错安粗岩和粗面岩中发现了大量的捕获锆石。地球化学分析显示,岩石ε_(Hf)(t)均为正值,但随SiO_2含量的增高,ε_(Hf)(t)有减小的趋势。稀土元素配分曲线上轻重稀土分馏明显,无或轻微Eu负异常,尤其是重稀土出现分馏,大多数样品(Sm/Yb)_N值介于6.30~8.25之间,表明原生岩浆起源于含有石榴石的弱亏损型软流圈地幔,中酸性岩浆所具有的类似埃达克岩的地球化学特征是原生幔源岩浆经AFC作用形成的。始新世末期南羌塘地区的火山活动可能与向北俯冲的拉萨地块的岩石圈地幔断离造成的软流圈上涌有关。 | 刘建峰 迟效国 赵秀羽 赵芝 董春艳 黎广荣 赵院东 | 2009 | 岩石学报2009，25，12： | 13 |
| 19 | Control scheme of hexagonal modular multilevel direct converter for offshore wind power integration via fractional frequency transmission system显示文摘A fractional frequency transmission system(FFTS)is a promising solution to offshore wind power integration,for which the hexagonal modular multilevel converter(Hexverter)is an attractive choice for power conversion.The Hexverter has recently been proposed to directly connect two three-phase systems of different frequencies and voltage amplitudes,with only six branches in the FFTS in that case.This paper examines for the first time the control scheme of the Hexverter when applied to offshore wind power integration via a FFTS.Firstly,the frequency-decoupled mathematical model of the Hexverter is deduced by introducing the double dq transformation.Then the branch energy of the Hexverter is analyzed in detail and the reactive power constraint equation is obtained.The corresponding control scheme is thoroughly discussed,including the inner loop current control,the outer loop voltage control in both grid-connected mode and passive mode,and a novel optimization method to minimize the circulating current in the Hexverter.Finally,a simulation model of offshore wind power integration via a 4-terminal FFTS based on the Hexverter is built in MATALB/Simulink to verify the feasibility of Hexverter and the effectiveness of the control scheme proposed in this paper. | Yongqing MENG Bo LIU Huiyong LUO Shuonan SHANG Haitao ZHANG Xifan WANG | 2018 | Journal of Modern Power Systems and Clean Energy2018，6，1： | 12 |
| 20 | Fractional order nonsingular terminal sliding mode control for flexible spacecraft attitude tracking显示文摘This paper investigates a fractional terminal sliding mode control for flexible spacecraft attitude tracking in the presence of inertia uncertainties and external disturbances. The controller is based on the fractional calculus and nonsingular terminal sliding mode control technique,and it guarantees the convergence of attitude tracking error in finite time rather than in the asymptotic sense. With respect to the controller,a fractional order sliding surface is given,the corresponding control scheme is proposed based on Lyapunov stability theory to guarantee the sliding condition,and the finite time stability of the whole close loop system is also proven. Finally,numerical simulations are presented to illustrate the performance of the proposed scheme. | GAO Junshan DENG Liwei SONG Shenmin | 2016 | Instrumentation2016，3，1： | 12 |
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