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21.
A long‐term pump test was conducted in the KTB pilot borehole (KTB‐VB), located in the Oberpfalz area, Germany. It produced 22 300 m3 of formation fluid. Initially, fluid production rate was 29 l min?1 for 4 months, but was then raised to an average of 57 l min?1 for eight more months. The aim of this study was to examine the fluid parameters and hydraulic properties of fractured, crystalline crusts as part of the new KTB programme ‘Energy and Fluid Transport in Continental Fault Systems’. KTB‐VB has an open‐hole section from 3850 to 4000 m depth that is in hydraulic contact with a prominent continental fault system in the area, called SE2. Salinity and temperature of the fluid inside the borehole, and consequently hydrostatic pressure, changed significantly throughout the test. Influence of these quantities on variations in fluid density had to be taken into account for interpretation of the pump test. Modelling of the pressure response related to the pumping was achieved assuming the validity of linear Darcy flow and permeability to be independent of the flow rate. Following the principle ‘minimum in model dimension’, we first examined whether the pressure response can be explained by an equivalent model where rock properties around the borehole are axially symmetric. Calculations show that the observed pressure data in KTB‐VB can in fact be reproduced through such a configuration. For the period of high pumping rate (57 l min?1) and the following recovery phase, the resulting parameters are 2.4 × 10?13 m3 in hydraulic transmissivity and 3.7 × 10?9 m Pa?1 in storativity for radial distances up to 187 m, and 4.7 × 10?14 m3 and 6.0 × 10?9 m Pa?1, respectively, for radial distances between 187 and 1200 m. The former pair of values mainly reflect the hydraulic properties of the fault zone SE2. For a more realistic hydraulic study on a greater scale, program FEFLOW was used. Parameter values were obtained by matching the calculated induced pressure signal to fluid‐level variations observed in the KTB main hole (KTB‐HB) located at 200 m radial distance from KTB‐VB. KTB‐HB is uncased from 9031 to 9100 m and shows indications of leakage in the casing at depths 5200–5600 m. Analysis of the pressure record and hydraulic modelling suggest the existence of a weak hydraulic communication between the two boreholes, probably at depths around the leakage. Hydraulic modelling of a major slug‐test in KTB‐HB that was run during the pumping in KTB‐VB reveals the effective transmissivity of the connected formation to be 1 to 2 orders of magnitude lower than the one determined for the SE2 fault zone.  相似文献   
22.
Prehensile wear has never formed the focus of a blind test in microwear studies and doubts remain about the formation, identification and interpretation of diagnostic prehension and hafting wear. The results of the presented blind tests demonstrate that prehension and hafting traces do form and that their formation is sufficiently systematic and patterned to allow valid and reliable interpretations. A combined approach, involving macroscopic, low power and high power analyses, is suggested as the most meaningful approach for consistent inferences.  相似文献   
23.
We propose a new methodology based on standard statistical processes for displaying and rigorously comparing the alloy composition of archaeological bronze alloys. Although traditional approaches using visual comparisons of histograms of alloying elements in an assemblage of archaeological objects are adequate for observing differences between these distributions, we argue that differences in sample size cannot be adequately accounted for without using a statistical approach. We demonstrate this methodology by comparing the alloy composition of bronzes from the sequence of Bronze Age cultures in Central China—Erlitou, Erligang (Zhengzhou, or early Shang), Anyang (late Shang) and Western Zhou. We suggest that this approach allows the identification and rigorous comparison of ‘regional alloying practices’, which in turn enables us to link the alloy composition of the objects with the intentions and skills of foundry workers.  相似文献   
24.
Nowadays, a growing number of researchers are investigating subjective attitudes of people toward their environment with ever-increasing spatial and temporal resolutions. It seems that researchers' interest in daily experiences is not merely a passing research fad, but rather that individuals in current societies find more interest in their own momentary experiences. They talk about their affective states, they spend considerable portions of their income on intangible experiences, and they instantly share personal ‘moments’ through various online social media platforms. These trends are even more apparent in the tourism and leisure industries which aim to generate positive experiences among individuals. This research note points out new directions in the exploration of experiences during tourism and leisure activities. It discusses a new relevant concept, subjective momentary experiences on one hand and presents novel methodological opportunities on the other. In order to portray these new trends, a case study that describes the episodic experiences of festival attendants in a high tempo-spatial resolution is presented.  相似文献   
25.
In the described studies with the aim of optimizing hydrated lime grout composition, the first measure was to reduce the water content of the grout using a highly efficient polycarboxylate ether-based superplasticizer, whereas the second measure was to increase the content of the inert limestone filler with an adequate grain size distribution. In this way, an attempt was made to achieve the best possible volume stability and strength properties of the hydrated lime grout, while continuing to fulfill the other necessary requirements regarding non-structural grouting works which are reported in the literature.

The results of the tests showed that a non-structural grout consisting of 1 volume part of hydrated lime CL 90-S and 3 volume parts of inert limestone filler, with 0.5% of the polycarboxylate ether based superplasticizer, fulfilled most of the established requirements, so that it is thus potentially suitable for re-attachment interventions on architectural surfaces.  相似文献   

26.
This paper shows the results of two passive experiments carried out at the European Volvi test site where a scaled building has been constructed. The first experiment was performed to study the motion of the structure excited by two small earthquakes. For one month, six strong-motion recorders were installed within the structure, at the top and at the basement. The analysis of the deformation of the structure has been assessed by computing the spectral ratio between the top and the bottom, with a special focus on soil-structure interaction. An analytical model was then proposed to reproduce the structure and soil-structure system behaviour. The soil-structure interaction was accounted for by using impedance functions. During the second experiment, we concentrated our efforts on the effect of the building vibration on the surface ground motion. An explosive shot was fired and several strong-motion recorders were installed on the ground close to the structure that allowed us to clearly identify a monochromatic wave coming from the building, in the time and frequency domains. This experiment allows us to demonstrate the non-negligible effect of the soil-structure-soil interaction that may disturb the surrounding ground motion.  相似文献   
27.
Following the Malta Convention/Valletta Treaty the preferable way for the physical protection of archaeological sites is in situ preservation. When planning in situ preservation, in addition to other issues, it is also necessary to consider changes in physical environment and their impact on in situ preserved remains. This is especially important when human interaction takes place. Recently, an increase in construction on the top of archaeological sites has occurred, thus the effects of heavy equipment compaction need to be studied in more detail.

This paper presents research on the effects of the use of heavy equipment (e.g. rammers and rollers) compaction on archaeological remains. For the purpose of our research, laboratory testing has been performed. In a custom-made steel box, artificial archaeological sites were created using layers of sandy silt and gravel. A variety of archaeological and modern artefacts were placed in these created environments. Some of them were equipped with strain gauges for deformation recording. Through a series of tests a servo-hydraulic piston was used, which simulated the dynamic loading of the artificial sites. Humidity and temperature were recorded before, during, and after each test. Since layers and artefacts were three-dimensionally recorded before and after each test, compaction of layers and movements of artefacts could be studied. With attached strain gauges and visual inspection following each test, deformations and thus damage to artefacts during different stages of loadings was recorded.

The goals of our laboratory tests were the development of a new methodological approach to study the effects of heavy equipment compaction to the archaeological sites, getting an insight into the problems of such tests, and the estimation of the applicability of their results. With the presented results, our research has been a step towards better understanding the effects of heavy equipment compaction on archaeological remains and thus to the preservation of archaeological sites in situ.  相似文献   
28.
Detailed information on the hydrogeologic and hydraulic properties of the deeper parts of the upper continental crust is scarce. The pilot hole of the deep research drillhole (KTB) in crystalline basement of central Germany provided access to the crust for an exceptional pumping experiment of 1‐year duration. The hydraulic properties of fractured crystalline rocks at 4 km depth were derived from the well test and a total of 23100 m3 of saline fluid was pumped from the crustal reservoir. The experiment shows that the water‐saturated fracture pore space of the brittle upper crust is highly connected, hence, the continental upper crust is an aquifer. The pressure–time data from the well tests showed three distinct flow periods: the first period relates to wellbore storage and skin effects, the second flow period shows the typical characteristics of the homogeneous isotropic basement rock aquifer and the third flow period relates to the influence of a distant hydraulic border, probably an effect of the Franconian lineament, a steep dipping major thrust fault known from surface geology. The data analysis provided a transmissivity of the pumped aquifer T = 6.1 × 10?6 m2 sec?1, the corresponding hydraulic conductivity (permeability) is K = 4.07 × 10?8 m sec?1 and the computed storage coefficient (storativity) of the aquifer of about S = 5 × 10?6. This unexpected high permeability of the continental upper crust is well within the conditions of possible advective flow. The average flow porosity of the fractured basement aquifer is 0.6–0.7% and this range can be taken as a representative and characteristic values for the continental upper crust in general. The chemical composition of the pumped fluid was nearly constant during the 1‐year test. The total of dissolved solids amounts to 62 g l?1 and comprise mainly a mixture of CaCl2 and NaCl; all other dissolved components amount to about 2 g l?1. The cation proportions of the fluid (XCa approximately 0.6) reflects the mineralogical composition of the reservoir rock and the high salinity results from desiccation (H2O‐loss) due to the formation of abundant hydrate minerals during water–rock interaction. The constant fluid composition suggests that the fluid has been pumped from a rather homogeneous reservoir lithology dominated by metagabbros and amphibolites containing abundant Ca‐rich plagioclase.  相似文献   
29.
辜应康  杨杰 《人文地理》2015,30(1):117-121
传统的旅游目的地形象测量只关注旅游者外显层面的认知过程,即测量旅游者外显评价,而忽略了对旅游者内隐认知的测量。本研究将内隐联结测验引入旅游目的地形象研究领域,同时结合自陈式问卷以香港和韩国为例探讨旅游目的地形象外显测量结果与内隐测量结果是否存在差异。研究结果表明,被试对香港和韩国的外显旅游目的地形象的认知不存在显著差异,而对两地内隐旅游目的地形象的认知存在显著差异。本研究有助于推进旅游者行为的内隐认知研究,同时丰富旅游目的地形象的测量方法并对旅游目的地营销具有重要的实践意义。  相似文献   
30.
本文介绍了出土漆器显微试片的制作方法,通过对试片的显微观察,可以使我们对涂膜断面、材质、下地组成及漆器制作方法进行详细的分析。  相似文献   
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