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油气藏评价与开发 1995年第1期 90-91页

作者： a.h.balch

P-S波转换反射波的极化方向和极性与P波的入射角有关。实际中经常会出现入射角反转引起极性反

关键词：反射波 P-S 极性

井间成像中正向散射和反向散射P波、S波和转换波的应用

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石油物探译丛 1992年第4期 76-89页

作者： a.h.balch 严建文

正象应用于地面地震数据一样,叠前偏移等成像方法的原理也适用于井间地震数据.然而,当这些成像方法应用于实际的井间地震数据时,就会出现一些在地面地震数据成像中很少或从未碰到的困难.如不连续点会使入射地震波沿任一方向反射或绕射.... 详细信息

正象应用于地面地震数据一样,叠前偏移等成像方法的原理也适用于井间地震数据.然而,当这些成像方法应用于实际的井间地震数据时,就会出现一些在地面地震数据成像中很少或从未碰到的困难.如不连续点会使入射地震波沿任一方向反射或绕射.如果不连续点位于震源线和接收器线之间,则可能记录到正向散射波或井间地震波同相轴,如果不连续点位于井间范围之外,则可能记录到反向散射波或井间范围之外的地震波同相轴.由于存在着各种可能的入射角,各种类型的反射波(P-P,P-S,S-P,和S-S)常常以近乎同等的机率出现,因为反射面的倾角从0°到±90°. 为了处理这些复杂性,我们首先利用波的偏振和视速度来对接收井中获得的波型进行分离.然后对那些由于扩散而引起的相位畸变进行补偿.最后,也是最重要的一步,我们对井间共炮点道集的数据进行偏移或成像.为此,我们借助于速度随机分布的逆时法,应用2D标量波动方程的有限差分解来将分离后的反射-绕射波场反向投影到介质中. 由于存在着4种反射波型(P-P,P-S,S-P和S-S),因此,我们要应用四种不同的成像条件.有了这些条件,我们就能够对那些来自井间区域内外的数据进行成像. 对每一个共炮点道集可重复进行这些运算,在每一个成像空间,每一个共炮点道集产生4个部分图像。以各种组合形式对这些众多的部分图像进行叠加,从而得到地下介质的最终图像. 我们应用固体(非流体)物理模型所作的实验表明:正确应用这些步骤可获得高质量的井间图像.即使产生绕射图像的一些弱的绕射波几乎被原始数据上其它的高振幅同相轴所掩盖,这些图像仍具有很高的清晰度.

关键词：正向散射反向散射井间成像

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莱奥Ⅰ组厚砂岩透镜体的地震振幅异常

国外油气勘探 1983年第4期 36-43页

作者： a.h.balch 任生祥黄汉明

美国怀俄明、内布拉斯加、南达科他三个州之间的东粉河盆地内明路沙层的中段,新发现了几处莱奥砂岩产油层。这些有经济价值的砂岩体,重新引起人们对该区的勘探兴趣。垂直地震剖面和模型研究表明,能测量到的地震振幅异常通常与莱奥I组厚... 详细信息

美国怀俄明、内布拉斯加、南达科他三个州之间的东粉河盆地内明路沙层的中段,新发现了几处莱奥砂岩产油层。这些有经济价值的砂岩体,重新引起人们对该区的勘探兴趣。垂直地震剖面和模型研究表明,能测量到的地震振幅异常通常与莱奥I组厚砂岩透镜体有关。为了证明这一说法,在相隔19公里远的二口井之间,布置了地震连井试验测线。其中一口井存在有工业价值的莱奥I组砂岩,另一口井莱奥I组是无油的薄砂岩。已知存在厚砂岩透镜体的那口井,地震剖面上预测有振幅异常显示。连井地震剖面上另外两处也出现莱奥I组砂岩振幅异常,这些异常预示存在有另外的砂岩透镜体。

关键词：砂岩透镜体砂岩体振幅异常垂直地震剖面地震勘探莱奥地震

作为巷道检测手段的层析成象反演:三维物理模型模拟的可行性研究

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作为巷道检测手段的层析成象反演:三维物理模型模拟的可行性研究

美国勘探地球物理学家学会第61届年会

作者： a.h.balch h.Chang 于锋玉 Colorado School of Mines Colorado School of Mines

巷道检测问题最近引起了从事废弃矿道检测和“复杂”巷道网识别方面的有关人员的关注。该项研究使用了一个三维弹性物理模型,在其上采集了15000个地震记录并据此得到几组实际比例模拟井间地震资料。这些资料均用于探讨用弯曲射线路径层...

巷道检测问题最近引起了从事废弃矿道检测和“复杂”巷道网识别方面的有关人员的关注。该项研究使用了一个三维弹性物理模型,在其上采集了15000个地震记录并据此得到几组实际比例模拟井间地震资料。这些资料均用于探讨用弯曲射线路径层析成象旅行时和振幅反演来检测巷道的可能性。物理模型是根据所掌握的真实野外资料而精心设计的,因此物理模拟结果可按比例放大来反映实际的野外问题。通过层析旅行时反演得到了高质量的巷道图象。但是,要求具有较小的井间间隔和较小的时间和空间采样以便能够检测到由地道引起的微小旅行时延迟（在有噪声的情况下）。由于旅行时反演对时间拾取误差很敏感,故精确地拾取初至时间亦很必要。层析振幅反演结果的分辨率低的原因是振幅响应的分辨率低,震源和接收器的耦合甚不一致以及对震源-接收器的方向特性了解甚少。不过,在做旅行时反演的同时兼做振幅反演所增加的费用是微不足道的,因此,我们可以把振幅反演结果作为旅行时反演结果的一种附助解释手段。按比例放大的物理模拟层析成象结果表明, 当介质的P波平均速度为12800英尺／秒,井间距为109英尺,炮点距和检波点距为1．65英尺的条件下直径为6．6英尺的巷道能够得以清楚地成象。

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多分量井间和VSP资料中P波和S波的分离

多分量井间和VSP资料中P波和S波的分离

Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

美国勘探地球物理学家学会第61届年会

作者： C. Erdemir a.h.balch K. Ranzinger 胡中平 Colorado School of Mines Colorado School of Mines Colorado School of Mines

为了处理井间地震和VSP方法记录的多分量地震资料,有必要将同相轴按P波和S波进行分离。本文描述的一种新的波型分离技术可以在时-空域中将多分量资料按P波和S波进行分离Ranzjnger（1990）。该方法已在井间和VSP弹性物理模型资料上验证,...

为了处理井间地震和VSP方法记录的多分量地震资料,有必要将同相轴按P波和S波进行分离。本文描述的一种新的波型分离技术可以在时-空域中将多分量资料按P波和S波进行分离Ranzjnger（1990）。该方法已在井间和VSP弹性物理模型资料上验证,结果用Dankbaar’s（1985,1987）的频率一波数（f-k）域波型分离方法得到的结果相当。虽然两种方法的结果基本上差不多,但当介质速度有变化时,我们的方法更有效。

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 543-562页

作者： h.M.FEIZABAD M.h.YAS Department of Mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQM)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQM)

holographic dark energy in non-conserved gravity theory

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Communications in Theoretical Physics 2024年第4期76卷 126-133页

作者： h R Fazlollahi Institute of Gravitation and Cosmology Peoples Friendship University of Russia(RUDN University)6 Miklukho-Maklaya StMoscow117198Russia

Recently, reconsidering the Rastall idea T_(μ;νν)^(v)=α_(,μ) through relativistic thermodynamics gives a new form for the scalar field α which led us to construct modern modified theory of gravity debugged ‘non-conserved gravity theory’ Fazlollahi 2023 Euro. Phys. J. C 83 923. This theory unlike other modified theories of gravity cannot directly explain the current acceleration expansion in the absence of the cosmological constant and or existence of other forms of dark energy. hence, in this study we have reinvestigated holographic dark energy Ρ_(X)~h^(2) in the non-conserved theory of gravity. In this context, the density and pressure of dark energy depend on the non-conserved term and density of the dust matter field. As shown, due to non-conservation effects on large-scale structures, unlike the original holographic model, our model onsets an acceleration epoch for the current Universe satisfies observations. Moreover, the interaction and viscous scenarios are studied for this model.

关键词： non-conserved gravity covariant form of thermodynamics holographic dark energy

Novel synthesis of stabilized Bi1-x-yGdxDyyO1.5 solid electrolytes with enhanced conductivity for intermediate temperature solid oxide fuel cells（SOFCs）

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Journal of Rare Earths 2024年第10期42卷 1903-1911页

作者： Ahmed h.Ibrahim Yehia M.Abbas h.A.Ayoub Marwa h.Ali Mustafa Aldoori Materials Science Laboratory Physics DepartmentFaculty of ScienceSuez Canal University Ministry of higher Education and Scientific Research Aliraqia University

herein,we report the synthesis of a Dy-Gd co-doped cubic phase-stabilized Bi2O3solid electrolyte system via solid-state processing under atmospheric *** with Dy3+and Gd3+has been observed to significantly enhance the densification process during sintering for stabilization purposes,thereby improving the electrical properties of δ-Bi2O3-type *** synthesized ceramics were characterized using X-ray diffraction（XRD）,field emission scanning electron microscopy-energy dispersive X-ray spectroscopy（FESEM-EDX）,thermal gravimetry/differential thermal analysis（TG/DTA）,and the four-point probe technique（4PPT）.XRD analysis reveals that the samples Bi1-x-yGdxDyyO1.5（y=0.05/x=0.05,0.10,0,15,and 0.20,and x=0.05/y=0.10,0.15,and 0.20） exhibit a stable face-centered cubic δ-phase and a mixed-phase crystallographic *** XRD analysis of the stabilized δ-phase suggests that the prepared oxides show a face-centered cubic（FCC） structure with a space group of *** micrographs reveal that the composition Bi0.90Gd0.05Dy0.05O1.5has no significant ***,an evident increase in the pore formation is observed as the amount of Gd2O3increases until it reaches 20%.This finding suggests that dense pellets are formed during the sintering process at 900-1000℃.The DTA analyses were performed to verify the phase stability,which agrees with the XRD *** electrochemical performance of the synthesized Dy-Gd co-doped Bi2O3solid electrolyte system was evaluated and analyzed in detail by using the electrochemical impedance spectroscopy（EIS） technique,Based on EIS and conductivity measurements,Bi0.75Gd0.20Dy0.05O1.5exhibits the lowest activation energy of 0.519 eV and the highest conductivity value of 0.398 S/cm at 627℃compared to the other samples;this composition can be used as a solid electrolyte for intermediatetemperature solid oxide fuel cells（SOFCs）.

关键词： Electrochemical impedance spectroscopy (EIS) Fast Fourier transform (FFT) Rare earths Rietveld Solid oxide fuel cells (SOFCs) Solid-state processing

Convexification of hybrid AC-DC Optimal Power Flow with Line-Commutated Converters

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 617-628页

作者： hongyuan Liang Zhigang Li J.h.Zheng Q.h.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

Line-commutated converter (LCC)-based high-voltage DC (hVDC) systems have been integrated with bulk AC power grids for interregional transmission of renewable power. The nonlinear LCC model brings additional nonconvexity to optimal power flow (OPF) of hybrid AC-DC power grids. A convexification method for the LCC station model could address such nonconvexity but has rarely been discussed. We devise an equivalent reformulation for classical LCC station models that facilitates second-order cone convex relaxation for the OPF of LCC-based AC-DC power grids. We also propose sufficient conditions for exactness of convex relaxation with its proof. Equivalence of the proposed LCC station models and properties, exactness, and effectiveness of convex relaxation are verified using four numerical simulations. Simulation results demonstrate a globally optimal solution of the original OPF can be efficiently obtained from relaxed model.

关键词： AC-DC power system convex relaxation linecommutated converter optimal power flow second-order cone programming

Shell-model representations of the microscopic version of the Bohr-Mottelson collective model

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Communications in Theoretical Physics 2024年第8期76卷 79-90页

作者： h G Ganev Joint Institute for Nuclear Research DubnaRussia Institute of Mechanics Bulgarian Academy of SciencesSofiaBulgaria

The structure of the irreducible collective spaces of the group Sp(12,R),which many-particle nuclear states are classified according to the chain Sp(12,R)⊃U(6)⊃SO(6)⊃SU_(pn)(3)⊗SO(2)⊃SO(3)of the proton-neutron symplectic model(PNSM),is considered in *** chain of the PNSM was recently shown to correspond to a microscopic shell-model version of the Bohr-Mottelson collective *** construction of the relevant shell-model representations of the Sp(12,R)group along this chain is considered for three nuclei with varying collective properties and from different mass *** is shown that the SU_(pn)(3)basis states of the Sp(12,R)representations belonging to the SO(6)irreps with seniorityυ≥υ0,withυ0 denoting the maximal seniority SO(6)irrep contained in the Sp(12,R)bandhead,are always Pauli allowed,but organized in a different way into different SO(6)*** is in contrast to the case of filling the levels of the standard three-dimensional harmonic oscillator and using the plethysm *** the SU_(pn)(3)multiplets withinυhe present work are important for the practical application of the microscopic version of the Bohr-Mottelson collective model.

关键词： microscopic shell-model version of the Bohr-Mottelson model proton-neutron symplectic model Sp(12,R)dynamical algebra shell-model representations