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地震速度预测岩性和孔隙度的硅屑岩物性分类

国外油气勘探 1993年第2期 174-187页

作者： lev vernik Amos Nur 朱起煌

为了研究硅屑岩的物性分类并设计可描述这类岩石物性参数之间关系的新模式,对于碎屑沉积层序中存在的各类岩石进行了大量的、高有效压力下的物性测量,建立了内容广泛的数据库。在光学显微镜、扫描电镜(SEM)和实验数据的基础上,划分了四... 详细信息

为了研究硅屑岩的物性分类并设计可描述这类岩石物性参数之间关系的新模式,对于碎屑沉积层序中存在的各类岩石进行了大量的、高有效压力下的物性测量,建立了内容广泛的数据库。在光学显微镜、扫描电镜(SEM)和实验数据的基础上,划分了四个重要的物性组:(1)纯净的砂屑岩;(2)蚀变的砂屑岩和长石砂岩;(3)瓦克岩;(4)砂质页岩。每个物性组都由不同的矿物组成、结构和粘土的构造位置来表征。第二组中的粘土矿物主要是不稳定硅酸盐矿物和岩屑的成岩分解产物,由此导致了这些颗粒支撑的岩石的弹性模量的急剧变小。另外页岩为基质支撑的岩性,在较低程度上瓦克岩也是如此,这就是在类似的孔隙度下它们的弹性模量低于前两组岩石的原因。据发现,每组岩石都有线性的纵波速度—孔隙度关系,且有很高的相关系数。与时间平均方程和线性回归法相比,这种方法可根据声波测井曲线得出相当准确的孔隙度估算或岩性预测,因为前两者都没有考虑岩石的矿物和结构因素。此外还发现,体现各物性组线性趋势特征的孔隙度—速度曲线,主要反映了成岩作用的过程。砂岩和页岩的初始岩化(固结作用),基本上表现为小规模的局部接触粘结,因为在颗粒界面发生了化学作用,因而具有切变模量急剧增大的特征。虽然这一成岩阶段的孔隙度缩减十分有限,但速度有明显增加。进一步的成岩作用表现为较为平缓的线性趋势,反映了相当可观的孔隙度缩减,其原因在于在温度作用下,颗粒支撑的岩石发生了溶解—沉淀,而基质支撑的岩石发生了粘土的相转化。

关键词：地震波速岩性预测孔隙度硅质岩物性分类

Factorizations of Finite Groups and Related Topics

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Algebra Colloquium 2020年第1期27卷 149-180页

作者： lev Kazarin Department of Mathematics Yaroslavl State UniversityRussia

This is a survey on the recent progress in the theory of finite groups with factorizations and around it,done by the author and his coauthors,and this has no pretensions to cover all topics in this wide area of *** particular,we only touch the great consequences of the fundamental paper of Liebeck,Praeger and Saxl on maximal factorizations of almost simple finite groups for the theory of groups with *** each case the reader can find additional references at the end of Section *** of the methods of investigation can be used to obtain information about finite groups in general,nilpotent algebras and related nearrings.

关键词： finite groups products of groups conjugacy classes Sylow subgroups Lie type groups factorizations

A search for evidence of small-scale inhomogeneities in dense cores from line profile analysis

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Research in Astronomy and Astrophysics 2018年第8期18卷 97-102页

作者： lev Pirogov Institute of Applied Physics Russian Academy of Sciences

In order to search for intensity fluctuations on the HCN（1-0） and HCO＋（1-0） line pro- files, which could arise due to possible small-scale inhomogeneous structure, long-term observations of high-mass star-forming cores S140 and S199 were carried out. The data were processed by the Fourier filtering method. Line temperature fluctuations that exceed the noise level were detected. Assuming the cores consist of a large number of randomly moving small thermal fragments, the total number of frag- ments is - 4 × 106 for the region with linear size - 0.1 pc in S140 and - 106 for the region with linear size - 0.3 pc in S 199. Physical parameters of fragments in S 140 were obtained from detailed modeling of the HCN emission in the framework of the clumpy cloud model.

关键词： lines profiles - molecular data - methods data analysis - ISM clouds - ISM molecules - ISM structure - ISM individual objects (S 140)

Multi-gene genetic programming extension of AASHTO M-E for design oflow-volume concrete pavements

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Journal of Road Engineering 2022年第3期2卷 252-266页

作者： Haoran Li lev Khazanovich Department of Civil and Environmental Engineering University of PittsburghPittsburghPA 15261USA

The American Association of State Highway and Transportation Officials Mechanistic-Empirical Pavement DesignGuide (AASHTO M-E) offers an opportunity to design more economical and sustainable high-volume rigid pavementscompared to conventional design guidelines. It is achieved through optimizing pavement structural andthickness design under specified climate and traffic conditions using advanced M-E principles, thereby minimizingeconomic costs and environmental impact. However, the implementation of AASHTO M-E design for low-volumeconcrete pavements using AASHTOWare Pavement ME Design (Pavement ME) software is often overly *** is because Pavement ME specifies the minimum design thickness of concrete slab as 152.4 mm (6 in.). Thispaper introduces a novel extension of the AASHTO M-E framework for the design of low-volume joint plain concretepavements (JPCPs) without modification of Pavement ME. It utilizes multi-gene genetic programming (MGGP)-based computational models to obtain rapid solutions for JPCP damage accumulation and long-term performanceanalyses. The developed MGGP models simulate the fatigue damage and differential energy accumulations. Thispermits the prediction of transverse cracking and joint faulting for a wide range of design input parameters and axlespectrum. The developed MGGP-based models match Pavement ME-predicted cracking and faulting for rigidpavements with conventional concrete slab thicknesses and enable rational extrapolation of performance predictionfor thinner JPCPs. This paper demonstrates how the developed computational model enables sustainable lowvolumepavement design using optimized ME solutions for Pittsburgh, PA, conditions.

关键词： Mechanistic-empirical pavement design guide Low-volume roads Concrete pavement Transverse cracking Joint faulting Multi-gene genetic programming(MGGP)

Factorizations of groups and related topics

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Science China Mathematics 2009年第2期52卷 217-230页

作者： AMBERG Bernhard KAZARIN lev Fachbereich 08 Universitaet MainzGermany Department of Mathematics Yaroslavl State University

This is a survey of some recent progress in the theory of groups with factorizations. Some of the methods can be used to obtain information about finite groups in general, nilpotent algebras and nearrings.

关键词： products of groups factorizations 20D40

Development and prospects of the fire space monitoring system in Kazakhstan

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Frontiers of Earth Science 2012年第3期6卷 276-282页

作者： lev SPIVAK Oleg ARKHIPKIN Gulshat SAGATDINOVA Space Research Institute National Center of Space Research and Technology Shevchenko Almaty 050010 Kazakhstan

This article provides a brief description of the fire space monitoring system in Kazakhstan, including the GIS-technology incorporated in its structure. The system performs operative space monitoring of fire areas and burnt areas, mapping of large fire areas, analysis of seasonal and long-term dynamics of burnt areas, and estimation of fire risk zones. Examples of output information obtained from space monitoring of fires are given. Possible directions of development of fire space monitoring in Kazakhstan are specified.

关键词： space images remote sensing fire space monitoring fire areas burnt areas operating mapping,zones of high fire risk

Exploration and determination of the principles of rotary-percussive underground slimhole drilling

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International Journal of Mining Science and Technology 2014年第2期24卷 245-249页

作者： Shadrina Anastasija Saruev lev Institute of Natural Resources Tomsk Polytechnic University Institute of High-Technology Physics Tomsk Polytechnic University

A possibility of the efficient use of rotary percussive drilling to provide drilling smaller diameter holes(40–70 mm) both in mining and prospecting is disclosed herein. A new construction designed for the nipple thread connection is described. The relative amplitude variation, change of power pulse time and energy in their propagation throughout the drilling tool are determined. A possibility of the efficient power pulse transfer along the drill string to the rock destruction tools with new nipple connections which allow automating the make-up and breakout system of drill pipe was supported by experiments.

关键词： Rotary-percussive drilling Smaller diameter holes Drill string Nipple thread connection Power pulse Percussive energy

Regulating dual-use research:Lessons from Israel and the United States

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Journal of Biosafety and Biosecurity 2019年第2期1卷 80-85页

作者： Ori lev Department of Public Policy and Administration Sapir Academic CollegeIsrael

Over the past 20 years,and with greater urgency since the H5N1 papers controversy(2012),dual-use research of concern(DURC)has been extensively debated by the scientific community,regulators,and the public at *** have raised the need to regulate DURC;however,despite the urgency of this issue,to date,only two countries have implemented specific regulations,United States and Israel(notably,China is in the final stages of creating a set of DURC-related regulations).In this paper,I have compared these policies as case studies that may benefit other ***,the present study aimed to critically compare the DURC policies of the US and Israel and determine whether their different approaches provide a rigorous framework for the regulation of DURC.I have shown that in some aspects,they have adopted similar approaches;for example,allowing local committees to play a role in assessing the ***,they differ in certain important aspects;for instance,the US policies have laid out a mechanism through which academic institutions and the government decide jointly on how to address risky studies,while the Israeli law places the authority solely in government *** aim in comparing the policies is twofold;first,to reveal the weaknesses and strengths of each policy,thereby aiding their improvement,and second,to provide those that are considering developing policies in this field an overview of what the current approaches look like,thereby enabling them to articulate their own approach while taking into account the experience gained by the US and Israel.

关键词： Antimicrobial resistance Extended spectrum beta lactamase(ESBL) Urinary tract infections(UTIs) Gram negative bacteria(GNB)

Nonlocal Free Energy of a Spatially Inhomogeneous Superconductor

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Communications in Theoretical Physics 2012年第5期57卷 879-892页

作者： K.V.Grigorishin B.I.lev Boholyubov Institute for Theoretical Physics of the Ukrainian National Academy of Sciences 14-b Metrolohichna str.Kiev-03680Ukraine

The microscopic approach is developed for obtaining of the free energy of a superconductor based on direct calculation of the vacuum *** free energy functional of the spatially inhomogeneous superconductor in a magnetic field is obtained with help of the developed *** obtained functional is generalization of GinzburgLandau functionals for any temperature,for arbitrary spatial variations of the order parameter and for the nonlocality of a magnetic response and the order ***,the nonlocality of the magnetic response is the consequence of order parameter's *** extremals of this functional are considered in the explicit form in the low-and high-temperature limit at the condition of slowness of spatial variations of the order parameter.

关键词： uncoupling of correlations vacuum amplitude order parameter magnetic response nonlocality