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排序方式: 共有692条查询结果,搜索用时 31 毫秒
1.
You Yage
YuZhi Associated Professor Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Guangzhou
. Professor Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Guangzhou 《中国海洋工程》1995,(4)
In this paper, the extreme wave loads on an on-shore wave power device are investigated. First, boundary element method is applied to solve the three dimensional potential problem based on the small amplitude wave assumption. Then the motion of the Oscillating Water Column (OWC) inside the device and its laods on the device are calculated in time domain. Several protective techniques often applied are simulated by changing the constraint of the upper end of the chamber of the device. Numerical results are used to judge the effectiveness of these techniques. The investigation shows that damping can not effectively restrain the motion of OWC when the period of incident wave is long, which may cause dangerous loads on the structure. The shut chamber can effectively restrain the motion of OWC, but alternatively cause high pressure in the chamber. A Contracting opening with a Taper (CT) can exhaust a great amount of kinetic energy of OWC, and significantly decrease the loads. It is a promising protective tec 相似文献
2.
3.
幔源CO_2释出机理、脱气模式及成藏机制研究进展 总被引:10,自引:0,他引:10
针对幔源CO2如何从地幔岩浆中脱出并进入沉积地层中形成CO2气藏聚集这一关键问题,总结了国内外研究进展和前缘方向。研究表明,地幔深部的碱性玄武岩浆和碱性岩浆才是深部流体和CO2等挥发份大量赋存、渗滤和释出的场所。浅成侵入岩、次火山岩和火山通道等是CO2释放和聚集的有利位置,岩浆期后和岩浆衰弱期的热液活动阶段是CO2大量释放和聚集的有利时期。幔源CO2进入沉积盆地中具有3种脱气模式,即沿岩石圈断裂直接脱气模式、热流底辟体脱气模式和壳内岩浆房-基底断裂组合脱气模式。CO2的固有物化性质决定其运移相态多样,具有运移和聚集过程同步的特征。只有在满足大量的化学消耗及地层水或原油的溶解和耗散之后才能形成CO2有效聚集。幔源CO2成藏和分布主要受岩浆气源体和气源断裂体系的控制。今后,在超临界CO2及其对油气运移聚集的作用、CO2与深大断裂及火山岩的关系、CO2脱气运移机制、CO与常规烃类油气的耦合差异成藏机制等方面仍需要进一步的研究和探索。 相似文献
4.
可调滞回模型的磁流变阻尼器及其试验 总被引:5,自引:0,他引:5
本文在现在磁流变阴尼器性能研究的基础上,提出了可调滞回模型的磁流变阻尼器及其试验方法,并进行理论、试验及算例分析。首先,根据恒定电流下磁流变阻尼器的阻尼力滞力特性,利用磁流变材料特性的电流(即磁场)可控特点,建立了变电流下的阻尼力滞回模型;其次,在中通过电路板控制外加电流与装置变形间的函数关系,实现了变电流调节的阻尼力滞回模型;最后,将磁流变阻尼器与橡胶隔震装置结合,形成智能磁流变隔夺装置,并对一个单自由度隔震结构进行了数值仿真分析。 相似文献
5.
Akihiro Takeuchi Hiroyuki Nagahama 《Physics of the Earth and Planetary Interiors》2002,130(3-4):285-291
Fracturing and frictional sliding of quartz and granite under dry condition generates fractoluminescence, charged particle emission and electromagnetic radiation. Various kinds of experiments indicate that surface charge density on fracture or frictional slip surface of quartz and granite is 10−4 to 10−2 C/m2 which is larger than bound charges induced by the disappearance of piezoelectricity due to the release of stress. Hole and electron trapping centers, which is found in semiconductor devices with the Si–SiO2 system, are causes of surface charging on fracture or frictional slip surface of quartz crystal. The quantity of the surface charge is enough to cause corona discharge that can generate earthquake lights. The mechanism considering the hole and electron trapping centers has a probability to explain why non-piezoelectric minerals or rocks generate electromagnetic phenomena. It can be one of origins of seismo-electromagnetic phenomena (SEP). 相似文献
6.
A general method is developed for optimal application of dampers and actuators by installing them at optimal location on seismic-resistant
structures. The study includes development of a statistical criterion, formulation of a general optimization problem and establishment
of a solution procedure. Numerical analysis of the seismic response in time-history of controlled structures is used to verify
the proposed method for optimal device application and to demonstrate the effectiveness of seismic response control with optimal
device location. This study shows that the proposed method for the optimal device application is simple and general, and that
the optimally applied dampers and actuators are very efficient for seismic response reduction. 相似文献
7.
为研究钢筋砼摩擦耗能支撑框架结构的动力反应性能 ,对其中的摩擦耗能器单元和框架杆单元的单元刚度和力学模型做了分析。钢筋砼摩擦耗能支撑单元由支撑杆单元和钢板—橡胶摩擦耗能器单元组成 ,支撑单元可取空间杆单元 ,摩擦耗能器单元为平面应力矩形单元。摩擦耗能器单元的剪切恢复力曲线为理想的弹塑性曲线 ,根据耗能器单元的力学模型 ,可确定其在每一时刻的刚度 ;框架结构空间杆单元的恢复力模型采用双线型模型 ,根据杆单元的力学模型 ,可确定其在每一时刻的刚度。并利用所编制的程序对十层单榀两跨空间普通框架和摩擦耗能支撑框架在地震作用下进行了弹塑性反应时程分析 ,结果表明耗能支撑框架的顶层最大位移明显小于普通框架 相似文献
8.
9.
设备树在路灯AM/FM/GIS系统中的应用研究 总被引:1,自引:0,他引:1
该文提出了AM/FM/GIS中基于“设备树”的设备设施管理模式,运用“设备树”来组织路灯电力网络中的设备设施对象;阐述了如何从设备设施的物理模型抽象出具有树状层次结构的逻辑网络模型,并根据该逻辑模型设计相应的数据结构来构建“设备树”;并介绍了设备树在南京市路灯AM/FM/GIS系统中的设计与实现。 相似文献
10.
C Werner G Chiodini D Voigt S Caliro R Avino M Russo T Brombach J Wyngaard S Brantley 《Earth and Planetary Science Letters》2003,210(3-4):561-577
An eddy covariance (EC) station was deployed at Solfatara crater, Italy, June 8–25, 2001 to assess if EC could reliably monitor CO2 fluxes continuously at this site. Deployment at six different locations within the crater allowed areas of focused gas venting to be variably included in the measured flux. Turbulent (EC) fluxes calculated in 30-min averages varied between 950 and 4460 g CO2 m−2 d−1; the highest measurements were made downwind of degassing pools. Comparing turbulent fluxes with chamber measurements of surface fluxes using footprint models in diffuse degassing regions yielded an average difference of 0% (±4%), indicating that EC measurements are representative of surface fluxes at this volcanic site. Similar comparisons made downwind of degassing pools yielded emission rates from 12 to 27 t CO2 d−1 for these features. Reliable EC measurements (i.e. measurements with sufficient and stationary turbulence) were obtained primarily during daytime hours (08:00 and 20:00 local time) when the wind speed exceeded 2 m s−1. Daily average EC fluxes varied by ±50% and variations were likely correlated to changes in atmospheric pressure. Variations in CO2 emissions due to volcanic processes at depth would have to be on the same order of magnitude as the measured diurnal variability in order to be useful in predicting volcanic hazard. First-order models of magma emplacement suggest that emissions could exceed this rate for reasonable assumptions of magma movement. EC therefore provides a useful method of monitoring volcanic hazard at Solfatara. Further, EC can monitor significantly larger areas than can be monitored by previous methods. 相似文献