井水位振荡试验及其结果

通过鲁04井的频率特性试验,求出了该井含水层系统的频率特性参数,固有振动周期为40.59s,阻尼系数为0.0362s-1。并且计算出鲁04井含水层的导水系数为1.8×10-3m2/s。利用这些结果解释了鲁04井对地震波响应比珍珠泉井差的原因     

风向与树木之生长

剖树木干部之断面,察其年轮之多少,约略可知其生长年代之久暂。由年轮之疏密,可考究其历年雨量之丰歉,因雨量丰沛,则滋长旺盛,年轮宽阔;若雨量稀少,则发育迟缓,年轮密狭,适与一寒一暑情形相似。此不过考究树体内部之组织,而与研究气候学者,以探     

A laboratory investigation into the settlement of a foundation on geogrid-reinforced sand due to cyclic load

Summary Laboratory model test results for permanent settlement of a shallow square foundation supported by geogrid-reinforced sand and subjected to cyclic loading are presented. During the application of the cyclic load, the foundation was subjected to a sustained static load. Tests were conducted with only one type of geogrid and at one relative density of compaction of sand. Based on the model test results, the nature of variation of the permanent settlement of the foundation with the intensity of the static loading and the amplitude of the cyclic load intensity are presented in a non-dimensional form.     

A direct determination of the oxygen isotope fractionation between quartz and magnetite at 600 and 800°C and 5 kbar

The partitioning of oxygen isotopes between quartz and magnetite was measured at 600 and 800 C and 5 kbar, using an internally heated pressure vessel equipped with a Shaw-membrane. Through adjustment of the hydrogen fugacity the starting material, fayalite, was decomposed to form quartz and magnetite. The isotopic composition difference between the separated quartz and magnetite fraction was measured directly. As the mineral separates were not completely pure, a correction was applied to the measured fractionations. The independence of the measured isotopic composition differences of run length, the initial isotopic composition of the starting materials as well as the isotopic composition difference between them suggests that the fractionations, 1000 In α_Q-M = 7.8 ± 0.4% at 600°C and 1000 In α_Q-M = 6.1 ± 0.2% at 800°C, represent equilibrium values.     

Contribution of E.S.R. analysis toward diagenic mechanisms in bituminous deposits

The E.S.R. g-values of a variety of bituminous materials have been plotted against a function of their heteroatom content ∑δ_κX_κ, where δ is the splitting coefficient of the given heteroatom κ, and X is its atomic fraction. Three discrete series are evident: two coal series, one exhibiting direct variation of g with ∑δ_κX_κ (Series I), the other exhibiting an inverse relationship (Series II). The petroleum asphaltenes, as well as most asphaltites and asphaltoids (Series III), lie above and roughly parallel to Series I. Sulfur-treated asphaltics approach Series I, whereas heated asphaltenes and resins are situated around the intersection of Series II and III.Bituminous deposits may transform through diagenesis to their mature forms, as evidenced by their increase in the delocalization (increased aromaticity) with a decrease in heteroatom content. The diagenesis of coal is reliant on oxygen whose elimination may result in aromatization (Series I), and further transformations may increase active peripheral oxygen function groups (Series II). The intersection of Series I and II contains the delocalization states. There exist major differences in the precursors and mode of transformation between members of the coal and asphaltene series.     

Simulation of the seismic performance of the Bolu Viaduct subjected to near‐fault ground motions

The seismic performance of the Bolu Viaduct in the Duzce, Turkey, earthquake of November 1999 was studied via a non‐linear, time‐history analysis of a multi‐degree of freedom model. The viaduct had a seismic isolation system consisting of yielding‐steel energy dissipation units and sliding pot bearings. The Duzce earthquake caused a surface rupture across the viaduct, which resulted in excessive superstructure movement and widespread failure of the seismic isolation system. The effect of the rupture was modeled by a static, differential ground displacement in the fault‐parallel direction across the rupture. The ground motions used in the analysis contain common near‐fault features including a directivity pulse in the fault‐normal direction and a fling step in the fault‐parallel direction. The analysis used a finite element package capable of modeling the mechanical behavior of the seismic isolation system and focused on the structural response of a 10‐span module of the viaduct. This analysis showed that the displacement of the superstructure relative to the piers exceeded the capacity of the bearings at an early stage of the earthquake, causing damage to the bearings as well as to the energy dissipation units. The analysis also indicated that shear keys, both longitudinal and transverse, played a critical role in preventing collapse of the deck spans. Published in 2004 by John Wiley & Sons, Ltd.     

Reservoir operation using grey fuzzy stochastic dynamic programming

This paper presents an optimal regulation programme, grey fuzzy stochastic dynamic programming (GFSDP), for reservoir operation. It is composed of a grey system, fuzzy theory and dynamic programming. The grey system represents data by covering the whole range without loss of generality, and the fuzzy arithmetic takes charge of the rules of reservoir operation. The GFSDP deals with the multipurpose decision‐making problem by fuzzy optimization theorem. The practicability and effectiveness of the proposed approach is tested on the operation of the Shiman reservoir in Taiwan. The current M5 operating rule curves of this reservoir also are evaluated. The simulation results demonstrate that this new approach, in comparison with the M5 rule curves, has superior performance with regard to the total water deficit and number of monthly deficits. Copyright © 2002 John Wiley & Sons, Ltd.     

Interannual variation of the diurnal convection cycle in the western North Pacific

Summary As revealed from the interannual variation of outgoing longwave radiation in the western Pacific, deep cumulus convection along the Meiyü-Baiu front and ITCZ is modulated by the anomalous summer circulation in the following manner: when the sea surface temperatures on the eastern tropical Pacific are anomalously warm (cold), cumulus convection is enhanced (suppressed) along the equator east of 150° E and along the Meiyü-Baiu front, but is suppressed (enhanced) along the equator west of 150° E and along a longitudinal zone (10° N–30° N) extending from the northern section of the South China Sea to the International Dateline. Since tropical deep cumulus convection exhibits a pronounced diurnal variation, the diurnal convection cycle in the western Pacific may undergo an interannual variation coherent with that of deep tropical cumulus convection. This inference is substantiated by our analysis of the diurnal convection cycle for 1980–1993 with 3-hour equivalent black-body temperature observed by the Japanese Geostationary Meteorological Satellite (GMS). As expected, the diurnal convection cycle in the western Pacific is subjected to an interannual variation in accordance with deep cumulus convection along the Meiyü-Baiu front and ITCZ. Except along the equator east of 150° E, the diurnal convection cycle does not exhibit a drastic interannual change in phase.     

Evaluation of seasonal patterns of hydraulic redistribution in a humid subtropical area,East China

Antecedent soil moisture or soil moisture status has a great impact on hydrological processes. Hydraulic redistribution (HR), a widely observed phenomenon, is defined as water distributed (typically at night) from moist soil to drier soil via plant roots, which plays an important role in soil moisture replenishment. Knowledge on seasonal patterns of HR and on the relationship between HR and soil water use is not fully understood. We investigated temporal variations in HR and total daily water use (Δθ) at stands of camphor and peach by monitoring soil moisture content in a humid region in eastern China. HR at the three locations reached its maximum values in summer (0.68 mm d⁻¹ to 1.15 mm d⁻¹) at depths of 15 cm and 35 cm. Redistributed water replenished 41% of water depleted in the soil at a 5–45-cm depth. Interestingly, normalized HR (i.e., HR/Δθ) showed a constant pattern during the growing season implying it is independent of seasonal climate alterations. This also indicated that HR had a stable effect on the replenishment of daily water use. Positive linear relationships between HR and Δθ were found at three measuring locations (camphor: R² = .35, p < .01; peach1: R² = .57, p < .01; peach2: R² = .63, p < .01), suggesting a relatively stable inherent linkage between HR and Δθ. This study suggested that hydrological processes involving soil moisture status or antecedent soil moisture, needs to take the HR effect into account across timescales from intraday to seasonal.