爆破振动参数在地质灾害鉴定中的运用

本文论述爆破振动参数在地质灾害鉴定中的运用。指出在作爆破振动地质灾害鉴定时,除对建筑物的设计、建筑材料、建筑史、用途、结构、内外环境、地基基础、变形特征进行详细的了解记录外,还必须了解其爆破源点与被鉴定对象之间的地质环境,确定其与地形地质条件有关的系数K,衰减指数α,鉴定对象的最大振幅对应的频率、速度、爆破点的位置及炸药用量,计算振动的安全距离与剖面图上两者之间距离进行比较,为鉴定提出合理的证据。     

大连市海洋资源与功能区划

为了科学合理的开发利用海洋资源，控制和引导海域使用方向，保护海洋环境，促进海洋资源和区域经济持续发展，为海洋综合管理提供服务，在全面调查大连市海域自然环境、自然资源、开发现状及存在问题和综合分析区域经济发展需求的基础上，确定了大连市海域及其毗邻陆域海洋功能区，并对贯彻实施海洋功能区提出了相关措施和建议。     

奥帆比赛与青岛城市环境的几个相关问题及对策

青岛是2008年北京奥运会部分水上项目承办城市，也是北京奥运的唯一伙伴城市；但是对照“绿色奥运”的理念和争办奥帆比赛时所作的承诺，青岛市在某些方面还存在一些不足．从城市综合环境、绿化环境、交通环境、大气环境和人文环境等几个不同侧面对存在问题作了分析，提出了解决问题的对策建议。     

沁水盆地阳泉区块太原组煤系页岩孔隙结构特征

页岩孔隙结构是影响页岩气赋存与储集的基本因素之一.为研究高演化海陆过渡相煤系页岩的孔隙结构和评价页岩气储集能力,主要运用扫描电子显微镜、高压压汞、低温N2和CO2气体吸附实验方法,对沁水盆地阳泉区块太原组海陆过渡相煤系页岩孔隙微观特征与孔隙结构进行了研究,并分析了太原组煤系页岩孔隙发育的影响因素.研究结果表明:沁水盆地...     

Are Type Ia Supernovae Reliable Distance Indicators？

Recent applications of type Ia supernovae(SNe Ia)in cosmology have successfully revealed the accelerating expansion of the universe.However,as distance indicators used in measuring the expansion history of the universe and probing the nature of dark energy,these objects must pass more strict tests.We propose a K-S test to investigate if there exists any systematic bias when deriving the luminosity distances under the standard candle assumption. Two samples,one comprising 71 high-redshift SNe Ia and the other,44 nearby ones,are used in our investigation.We find that it is likely there exists a bias in the adopted samples,which is probably caused by a systematic error,e.g.in the color parameter used in the luminosity calibration and a bias may be caused by the SN evolution or by varying properties of the dust surrounding the SNe Ia.     

Comparison between iterative solution of symmetric and non‐symmetric forms of Biot's FEM equations using the generalized Jacobi preconditioner

Finite element discretization of Biot's consolidation equations can produce a symmetric indefinite system (commonly used in geomechanics) or a non‐symmetric system. While this difference appears to be minor, however, it will require the selection of entirely different Krylov subspace solvers with potentially significant impact on solution efficiency. The former is solved using the symmetric quasi‐minimal residual whereas the latter is solved using the popular bi‐conjugate gradient stabilized. This paper presents an extensive comparison of the symmetric and non‐symmetric forms by varying the time step, size of the spatial domain, choice of physical units, and left versus left–right preconditioning. The generalized Jacobi (GJ) preconditioner is able to handle the non‐symmetric version of Biot's finite element method equation, although there are no practical incentives to do so. The convergence behaviour of GJ‐preconditioned systems and its relation to the spectral condition number or the complete spectrum are studied to clarify the concept of ill‐conditioning within the context of iteration solvers. Copyright © 2007 John Wiley & Sons, Ltd.     

乌蒙山区脱贫致富途径初探

本文论述了乌蒙山区经济社会主要特点,剖析了贫困落后的各种制约因素,提出了今后脱贫致富的若干途径与措施。     

On the deprojection of clusters of galaxies combining X-ray, Sunyaev–Zeldovich temperature decrement and gravitational lensing maps

Knowledge of the intrinsic shape of galaxy clusters is very important in investigating cosmic structure formation and astrophysical processes. The reconstruction of the 3D structure usually relies on deprojecting 2D X-ray, Sunyaev–Zeldovich (SZ) and/or gravitational lensing observations. As known, a joint analysis of these data sets can provide the elongation of the cluster along the line of sight together with its length and width in the plane of the sky. An unbiased measurement of the Hubble constant can be also inferred. Due to some intrinsic degeneracies, the observational constraints obtained from such projected data sets are not enough to allow an unique inversion. In general, the projected maps can be at the same time compatible with prolate, oblate and with many triaxial configurations. Even a prolate cluster might be interpreted as an oblate system and vice versa. Assuming that the cluster is axially symmetric is likely to overestimate the intrinsic ellipticity, whereas the system always looks rounder performing the inversion under the hypothesis of a triaxial cluster aligned with the line of sight. In general, analysing triaxial clusters under the prolate or oblate assumption may introduce strong biases even when the clusters are actually near to axial symmetry whereas the systematics introduced assuming the cluster to be aligned with the line of sight are more under control.     

郑州大学东校区场地地震地质条件及抗震设防应对措施

通过校区建筑场地钻孔岩土剖面与剪切波速测试结果以及地震地质背景条件、活动断裂及其影响和主要抗震设防参数的分析研究 ,作者认为建筑场地属中软土 ,但不存在液化可能性 ,建筑场地类别可定为Ⅱ类 ;并提出近场区存在 6级及小于 6级的地震背景 ,其地震烈度可估评为 7度。鉴于此 ,建议建筑场地可采用换土垫层法以加固地基 ,对高层建筑可采用大直径灌注桩基础、框架柱可一柱一桩、剪力墙宜设基础梁并适当扩大桩距、建筑体适当埋深和设置地下室等系列抗震设防措施