工业区位因素变化与工业地理学研究的新动向

工业生产在国家和地区社会经济发展中的作用表现为阶段性变化,并在工业区位因素和工业空间特征的变化上表现出来。80年代以来,这种变化突出表现为技术因素和社会文化因素对工业生产和工业区位的影响日盆增强以及工业生产组织的国际合作的扩展,这种变化导致了工业地理学研究方法和研究领域的革新拓展。     

L_p估计的计算问题

本文对Ｌｐ估计的直接算法进行了详细的分析和讨论，由于直接算法效率低，文中提出了一种快速算法（残差逐步下降法），采用可变尺度因子来修正Ｈｕｂｅｒ的常数尺度因子。最后，以实例加以分析和说明。     

采用阶梯抽水试验资料确定含水层参数

本文采用阶梯降深的有关公式,结合某矿区的一次多孔抽水试验资料进行试算,并和雅柯布直线法和恢复水位法求得的参数比较,汁算结果令人满意,表明该法是种简便、有效的求参手段。     

豫西南矽线石物相分析方法研究

以豫西南地区4个矿区的矿物组合为依据,建立了铝量法测定矽线石含量的物相分析方法。对比了不同方法制备的矽线石及其不同存在条件下溶解率的差异,确定了接近矿区实际的、准确合理的分析结果校正办法。     

On the propagation of an in-plane shear fault with super-S-wave velocity

The speedv, especially the problem whether super S-wave velocity in the classical model (linear elasticity fracture mechanics) exists, of spontaneous propagation of a shear fault is investigated theoretically. An in-plane shear crack propagating in the crack plane is taken as the model of the shear fault. The results obtained firstly by Kostrov (1975) is extended from sub-Rayleigh wave velocity to super S-wave velocity, and the analytical expression for the stress intensity factorK ₂ in the case ofα>v>β is derived. It is proved that for Poisson mediumK ₂ is positive and real in the velocity range (β, 1.70β). This demonstrates that (β, 1.70β) is the velocity range which fulfils the conditions for spontaneous crack propagation. The existence, convergence and positiveness or negativeness ofK ₂ forv in individual sections are examined, and it is found that for an in-plane shear crack: 1. There are three sections forv, i.e., [0.v _R], (β, 1.70β), andα, respectively, and 2. There are two physically reasonable sections forv, the first is [v _R, β], and the second is [1.70β, α]. These two forbidden sections behave as barriers to fault propagation. The analytical expressions derived in this paper are not only suitable to classical model, but also to the other derivative models (e. g., the slip-weakening model and the renomalization model etc.). The model considered in this paper is more realistic than the static model employed by previous authors. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica, 15, 9–14, 1993.     

华北地块北缘AuAgCuPbZn成矿规律

根据研究区成矿地质背景,分析了地层、构造、岩浆岩等因素对华北地块北缘Au、Ag、Cu、Pb、Zn成矿的控制作用,总结了矿床的时、空分布,共生组合特点,提出了成矿规律.     

Inherent relationship of the USLE,RUSLE topographic factor algorithms and its impact on soil erosion modelling

ABSTRACT

The accurate representation of the Earth’s surface plays a vital role in soil erosion modelling. Topography is parameterized in the Universal Soil Loss Equation (USLE) and Revised USLE (RUSLE) by the topographic (LS) factor. For slope gradients of < 20%, soil loss values are similar for both models, but when the gradient is increased, RUSLE estimates are only half of those of USLE. The study aims to assess the validity of this statement for complex hillslope profiles. To that end, both models were applied at eight diverse mountainous sub-watersheds. The USLE and RUSLE indices were estimated utilizing the SEAGIS model and a European dataset, respectively. LS factors were in a 3:1 ratio (i.e. USLE:RUSLE) considering the entire basin area. For areas with slopes <20%, gross erosion estimates of both models converged. Sites of strong relief (>20%) USLE yielded significantly higher values than RUSLE.     

Foraminiferal associations of the Mid-Tertiary Edegem Sands at Terhagen, Belgium

A factor-analytic approach (varimax rotated factors) was used in studying the benthonic foraminiferal associations of the Mid-Tertiary Edegem Sands at Terhagen (near Antwerpen) Belgium. The fauna can be described by two groups. The lower and upper part of the stratigraphic section are characterized by one group and the middle transitional part by a second group. The results can be correlated with the number of the planktonic forms and with the fossil richness of the sediment.     

Influence of rainfall on the deformation and stability of a slope in overconsolidated clays: a case study

The behaviour of an instrumented unstable slope in a profile of weathered overconsolidated clay has been analysed. Available field investigation data and laboratory tests were integrated in a coupled hydromechanical model of the slope. Particular attention was given to the unsaturated soil conditions above the water table and to the influence of the rainfall record. Recorded pore-water pressures helped to identify the hydrogeological conditions of the slope. The coupled model was used to compute slope deformations and the variation of safety with time. Actual rainfall records were also integrated into the analysis. Comparison of measurements and calculations illustrate the nature of the slope instability and the complex relationships between mechanical and hydraulic factors. Electronic Publication     

A study on the allocation of productive factors of Chinese agriculture

Background of Study on Allocation of Agricultural Productive Factors in ChinaAgricultal productiVe factors include land, labor, fendirer, approved variety, fann machinery, waterconservanCy facilihes, etc. The allocation of aghcultural productiVe factors is defined as the combinationof agricultural productiVe factors corresponding to regional natural condihons and economic situationIt is a requirement of Chinese agricultural prachce to StUdy the allocation of agricultUlal produchvefactors…