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101.
从贝丘遗址看绳纹人与环境的相互关系   总被引:1,自引:0,他引:1  
袁靖 《地球科学进展》1995,10(4):383-386
介绍了自本世纪70年代末以来,日本学者在绳纹时代的考古研究中开辟的一个新领域,即通过分析贝丘遗址和周围的自然环境去认识绳纹的环境变化及绳纹人与环境的关系。同时提出了笔者关于绳纹时代人与环境关系的一个模式。  相似文献   
102.
对1966年3月8日和3月22日台地震中的房屋破坏情况进行统计,计算了地震区主要房屋土坯墙房在Ⅳ~Ⅸ度中的毁坏率、严重破坏率和中等破坏率。通过X ̄2检验得出,Ⅵ度和Ⅸ度区房屋毁坏率、严重破坏率和中等破坏率的分布均服从正态分布  相似文献   
103.
In this article I describe a site survey facility, which measures the signals of the solar equivalent of a Differential Image Motion Monitor (S-DIMM) and of a six element linear array of solar scintillometers. Combining the S-DIMM r o andscintillometer I observations allows the determination of the fractions of the seeing in the free atmosphere and in the ground/lake layer. From the scintillometer array observations C n 2 (h) is determined for heights corresponding to the first 500 m along the line-of-sight. With minor changes this seeing monitor can also be used for other extended objects like the Moon and planets.  相似文献   
104.
安徽地区地震波衰减、场地响应及震源新参数的测定   总被引:5,自引:2,他引:5  
根据安徽数字地震台网7个地震台的143条波形资料,研究了安徽地区的衰减模型和各台站的场地响应。采用三段几何衰减模型拟合,得到了安徽及邻近地区的几何衰减函数,得到安徽地区非弹性衰减Q值随频率f的关系为Q(f)=235.3×f0.616;7个台站的场地响应均无明显的放大效应,这与它们均处于岩石地基相符;并在本地区地震预测研究中尝试使用新参数,进行了初步的应用。  相似文献   
105.
Pasargadae complex had been the main center of Persian history during the Achaemenian period (560–330 bc), registered as one of the world heritage sites by UNESCO in 2004. This research is an attempt to recognize the natural setting and landscape of Pasargadae during the Achaemenian period, in Iran. The method is based on the application of a multi-layer technique. Collected data by fieldwork, especially in geology, hydrology, and hydrogeology, along with the analysis of aerial data and satellite information provided the baseline information for preparing historic and environmental layers and have made it possible to recognize a natural lakelet in the this area. The results show that the geometry of lakelet together with the ancient river of Pasargadae had been the main elements that formed the character of the site; they were also important in the locations of buildings in the Pasargadae complex.  相似文献   
106.
Unnaturally high hydraulic gradients below dam sites enhance dissolutional widening of fractures in limestone. A model is presented which suggests that under unfavorable conditions, leakage rates could become unbearably high during the lifetime of the dam. At the beginning when water is impounded, leakage rates are low and increase slowly. A positive feedback loop, however, causes a sudden dramatic increase of leakage within a few years. Deep grouting becomes necessary to prevent such failures. Inefficiencies in grouting may leave some open fractures in the grouting curtain. These fractures widen faster than pathways below the grouting curtain, and reduce the effect of the grouted region located below. Therefore, open fractures act in a similar way as reduction of the grouting depth.  相似文献   
107.
Sporopollen analysis on a 346 cm peat record at Dahu, Jiangxi, chronologically constrained by 16 AMS 14C datings, provides an opportunity to reconstruct the vegetation evolution stages responding to cli-mate change in South China since the last glacial maximum. The result shows that during 18330-15630 cal a B.P., broad-leaved forest dominated the area, corresponding to mild, cool and fairly humid climate. At the interval of 15630-11600 cal a B.P., several evergreen broad-leaved species appeared within the broad-leaved forest, indicating moderate and humid condition. During early Holocene, broad-leaved evergreen forest community was constructed as Castanopsis/Lithorcarpus principally developed, suggesting a warm and humid scenario until 6000 cal a B. P. Since 6000 cal a B. P., abrupt forest deterioration happened with an contemporary increase of fern and herb communities, repre-senting a turnover to relatively cool and dry condition and as well, possible impact from human activi-ties. Meanwhile, several relatively cool and dry events can be identified in the sporopollen record, they can be correlated to the North Atlantic Heinrich event, YD and Holocene millennial-scale oscillations, implying that the low latitude climate was coupled with high latitude influences. Moreover, the varia-tions of temperature and humidity since LGM at Dahu were much smaller when compared with the re-cords in north monsoonal China.  相似文献   
108.
The damage distribution in Adra town (south‐eastern Spain) during the 1993 and 1994 Adra earthquakes (5.0 magnitude), that reached a maximum intensity degree of VII (European Macroseismic Scale (EMS scale)), was concentrated mainly in the south‐east zone of the town and the most relevant damage occurred in reinforced concrete (RC) buildings with four or five storeys. In order to evaluate the influence of ground condition on RC building behaviour, geological, geomorphological and geophysical surveys were carried out, and a detailed map of ground surface structure was obtained. Short‐period microtremor observations were performed in 160 sites on a 100m × 100m dimension grid and Nakamura's method was applied in order to determine a distribution map of soil predominant periods. Shorter predominant periods (0.1–0.3 s) were found in mountainous and neighbouring zones and larger periods (greater than 0.5 s) in thicker Holocene alluvial fans. A relationship T = (0.049 ± 0.001)N, where T is the natural period of swaying motion and N is the number of storeys, has been empirically obtained by using microtremor measurements at the top of 38 RC buildings (ranging from 2 to 9 storeys). 1‐D simulation of strong motion on different soil conditions and for several typical RC buildings were computed, using the acceleration record in Adra town of the 1993 earthquake. It is noteworthy that all the aforementioned results show the influence of site effects in the degree and distribution of observed building damage. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
109.
水溶性污染物在土壤中转化的原位实验方法   总被引:3,自引:0,他引:3  
建立了一种研究水溶性污染物在土壤中运转化的原位实验方法,该方法已成功地应用于研究黄土中氨氮的运移转化规律,克服了土柱实验存在的破坏土壤结构及氧化还原电位发生变化等所引起的实验误差。  相似文献   
110.
利用目前9210通信卫星网络中所获得的气象资料,实现大气环流场资料的自动处理和追加,并在MICAPS平台上进行二次开发,按月、旬、候的方式处理成Micaps系统的4类数据格式,分类存放。建立了本地短期气候预测业务平台。系统由资料训系统、短期气候预测系统、实时监测决策服务系统3个子系统组成。  相似文献   
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