THREE KINDS OF TIME DISTRIBUTION FUNCTIONS OF REMARKABLE EARTHQUAKES IN SEISMIC SEQUENCES     

Diao Shouzhong Wang Hongwei Chao Hongtai Hua Aijun 《地震研究》1998,(1)

ＴＨＲＥＥＫＩＮＤＳＯＦＴＩＭＥＤＩＳＴＲＩＢＵＴＩＯＮＦＵＮＣＴＩＯＮＳＯＦＲＥＭＡＲＫＡＢＬＥＥＡＲＴＨＱＵＡＫＥＳＩＮＳＥＩＳＭＩＣＳＥＱＵＥＮＣＥＳＤｉａｏＳｈｏｕｚｈｏｎｇＷａｎｇＨｏｎｇｗｅｉＣｈａｏＨｏｎｇｔａｉＨｕａＡｉｊｕｎ（Ｓｅｉ...  相似文献   

非迭代,非线性二维重力反演计算方法   总被引：1，自引：0，他引：1  

赵冠华  曾华霖 《物探化探计算技术》1998,20(1):36-41

本文叙述了非迭代、非线性二维重力反演方法的原理、模型计算及应用效果等。与以往诸多的求界面重力反演方法相比,该法的主要特点是：将界面的深度用一幂级数的形式表示,且幂级数系数的计算与界面上下地层的密度差无关。因此,一旦求出了幂级数的系数,由界面的密度差可直接得到界面的深度,且幂级数收敛的速度很快。  相似文献   

Determination of characteristics of steam reservoirs by Radon-222 measurements in geothermal fluids     

F. D'Amore  J. C. Sabroux  P. Zettwoog 《Pure and Applied Geophysics》1978,117(1-2):253-261

The authors conducted a Rn²²² survey in wells of the Larderello geothermal field (Italy) and observed considerable variations in concentrations. Simple models show that flow-rate plays an important part in the Rn²²² content of each well, as it directly affects the fluid transit time in the reservoirs. Rn²²² has been sampled from two wells of the Serrazzano area during flow-rate drawdown tests. The apparent volume of the steam reservoir of each of these two wells has been estimated from the Rn²²² concentration versus flow-rate curves.List of symbols Q Flow-rate (kg h^–1) - Decay constant of Rn²²² (=7.553×10^–3 h^–1) - Porosity of the reservoir (volume of fluid/volume of rock) - ₁ Density of the fluid in the reservoir (kg m^–3) - ₂ Density of the rock in the reservoir (kg m^–3) - M Stationary mass of fluid filling the reservoir (kg). - E Emanating power of the rock in the reservoir (nCi kg _rock ^–1 h^–1). - P Production rate of Rn²²² in the reservoir: number of atoms of Rn²²² (divided by 1.764×10⁷) transferred by the rock to the mass unit of fluid per unit time (nCi kg _fluid ^–1 h^–1). - N Specific concentration of Rn²²² in the fluid (nCi kg^–1) - Characteristic time of the steam reservoir at maximum flow-rate (=M/Q)  相似文献   

Longshore variations in nearshore wave processes at magilligan point,northern ireland     

R. W. G. Carter 《地球表面变化过程与地形》1980,5(1):81-89

Magilligan Point is a recurved cuspate foreland at the mouth of Lough Foyle. Two wave regimes intersect in the estuary mouth and the manner of their interplay controls shoreline changes. Ocean swell waves from the N and NE are refracted around the recurve, losing both height and energy longshore. Width of the surf zone decreases and waves tend to steepen, although both these changes and wave refraction owe something to nearshore geometry. Angle of wave approach becomes more acute and a westerly flowing longshore current moves sand S and SW along the beach. Estuary waves from the S and SW are wind-driven with high-frequencies and steepnesses. They generate a northeasterly current which returns material N, but dies out as the waves become obliterated by nearshore attenuation and breaking of swell. It is possible to identify a time-averaged null-point where shoreline wave power is balanced, although this tends to shift over short periods causing rapid morphological changes. The existence of two independent, but counteractive cells ensures the long-term maintenance of the foreland, without requiring major or continuous supplies of fresh sediment.  相似文献   

At‐a‐station hydraulic geometry relations, 1: theoretical development     

Vijay P. Singh  L. Zhang 《水文研究》2008,22(2):189-215

This paper, the first of two, hypothesizes that: (1) the temporal variation of stream power of a river channel at a given station with varying discharge is accomplished by the temporal variation in channel form (flow depth and channel width) and hydraulic variables, including energy slope, flow velocity and friction; (2) the change in stream power is distributed among the changes in flow depth, channel width, flow velocity, slope, and friction, depending on the boundary conditions that the channels has to satisfy. The second hypothesis is a result of the principle of maximum entropy and the theory of minimum energy dissipation or its simplified minimum stream power. These two hypotheses lead to families of at‐a‐station hydraulic geometry relations. The conditions under which these families of relations can occur in the field are discussed. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

利用牡蛎壳粉制备缓释氮肥的初步研究   总被引：1，自引：0，他引：1  

苗艳丽洪鹏志  宋文东 《广东海洋大学学报》2007,27(6):86-88

目前我国化肥当季利用率中，氮约为30％～35％．磷为10％～25％，钾为35％～50％远低于世界发达国家水平，造成肥料利用率低的主要原因是淋溶损失，尤以氮肥、钾肥为最。人们正在努力寻求提高肥料利用率的方法，其中之一是对肥料本身进行改性，开发适合于作物生长需求的新型肥料。研制缓／控释肥料是世界各国普遍采用的有效措施之一。缓释肥料的优点是利用率高，养分损失少，环境友好。但是，目前所用的作为缓释材料的高分子聚合物一般是难降解或不能降解，长期施用也会引起土壤污染。牡蛎壳为一种新型的天然材料，  相似文献   

广西山地风能资源开发利用可行性分析——以大容山为例     

黄梅丽  史彩霞  谭强敏  苏志 《成都信息工程学院学报》2007,22(2):247-252

利用大容山自动观测站2004年8月～2006年7月气象观测资料和容县气象站1958～2006年7月测风资料,对大容山的风能资源各参数进行了详细计算和分析,并结合预选风电场的地形地貌、交通运输、联网条件、环境保护等状况对大容山风能资源开发利用进行了可行性分析评价.结果表明：大容山年平均风速为7.2m/s,年平均风功率密度为390.8W/m^2,其风能资源丰富,且交通运输、联网、工程地质等条件较好,可选择在坡度较小的山头或山腰建设风电场,预选风电场可布置750kW的风机45台,总装机容量约为34MW.  相似文献   

基于MSP430F135的货车防盗报警系统设计     

靳建波  吴晓红  王正勇  何小海  卿粼波 《成都信息工程学院学报》2007,22(5):610-613

针对当前铁路运营的实际情况,设计并实现了基于MSP430F13x系列单片机的货车防盗报警系统.详细介绍了系统的原理和软、硬件设计.系统在货车遭遇破封的情况下触发报警器,并将报警信息以无线电信号发射出去.接收机接收报警信息并将其在LCD上显示出来,以便民警即时处理.经实际应用证明系统性能良好.  相似文献   

海上风电楔形单桩基础竖向承载力特性分析     

《海洋技术学报》2024,(1)

为提高基础利用率增加海上风电设施的可行性，对楔形单桩基础竖向承载力特性进行研究分析。采用PLAXIS 3D 有限元软件建立楔形单桩基础模型，从桩侧摩阻力、桩侧法应力及土体位移对比分析楔形单桩基础与等截面单桩竖向承载特性差异，并探讨内摩擦角、楔角及楔高对承载力的影响。研究表明：楔形单桩基础竖向承载力高于等截面单桩基础，且承载力随着楔角、楔高的增大而增大，提高率最大达24.786%。倾斜侧壁的引入改变了桩侧摩阻力的传递规律；倾斜侧壁挤密桩周土体，桩侧摩阻力与法向应力增大，从而有效提高单桩基础的竖向承载力。研究成果可为今后海上风电单桩基础截面型式的设计提供参考。  相似文献   

海洋能源获取、传输与管理综述     

杨灿军  陈燕虎 《海洋技术学报》2015,34(3):111-115

海洋能源获取、传输与管理是实现海洋透明化的关键技术。以能源获取的方式进行分类调研,分析探讨国内外海洋能源的获取、传输与能源管理方法,以及各个方式的优缺点,并对能源获取、传输与管理进行核心技术分解,对比我国研究现状得出各个技术与国外现有差距,预测我国在该技术领域的未来发展趋势。  相似文献