双功能地震记录仪报警器

本文阐述了地震仪双功能报警器的基本原理和结构特点。     

简易式钢模台车的设计和应用

介绍了一种适用小高宽比隧道的简易式钢模台车的设计和应用方法。这种台车在满足掘进和衬砌平行作业的前提下,将台车上调幅机构中的升降机械独立,由外部千斤顶代替。该台车在诸既市山公路隧道中得到成功的应用。     

EDA技术结合μClinux操作系统在地震前兆仪器中的应用

应用Altera公司的Quartus Ⅱ、NIOSⅡIDE开发软件和SOPC Builder工具,采用cy-cloneⅡ系列FPGA芯片--EP2C35,设计了质子式旋进磁力仪原理主机硬件平台.构建和配置了Nios Ⅱ软核处理器、IO接口电路及传感器控制电路,编写了全数字锁相环、等精度计数器等硬件单元的VHDL代码,实现了质子旋进式磁力仪器原理主机核心电路的单芯片系统逻辑设计.研究了μClinux嵌入式操作系统的配置技术,并建立了基于Nios Ⅱ软核处理器的μClinux交叉编译环境,成功将μClinux移植到NiosⅡ环境中.在该系统下编写了主机硬件平台的设备驱动程序和用户程序,实现了原理样机各设计功能,达到了预期目标.     

Three-dimensional saltating processes of multiple sediment particles

The purpose of this study was to investigate the interacting mechanism between the saltating particles near a channel bed. A three-dimensional real-time flow visualization technique was developed to measure the interparticle collision behaviors during the saltating process. Based on the experimental data, the distribution of the collision points was found to be symmetric. This confirms the assumption that the projections of the collision points onto the reasonable plane are uniformly distributed. A three-dimensional saltating model was also developed. This model produced satisfactory results. The model is able to simulate the continuous saltating trajectories of several particles. The simulated dimensionless saltating height, longitudinal and vertical saltation velocity components were found to increase as the dimensionless particle diameter and the dimensionless flow transport capacity parameter increase, while the simulated lateral saltation velocity component varies inversely with the dimensionless flow transport capacity parameter. A regression equation for the bed load transport rate was also obtained.     

青海大柴旦6．3级地震现场应急工作主要经验及反思

2008年11月10日青海省大柴旦发生6．3级地震。地震发生后,青海省各级政府及各相关部门高度重视,立即启动了省、州（地、市）、县三级地震应急预案,使得地震现场应急工作反应快速、措施得当、效果明显;同时也反映出日常工作中存在的一些问题,值得重视和反思。     

Evaluation of FAD-associated purse seine fishery reduction strategies for bigeye tuna (Thunnus obesus) in the Indian Ocean

In the Indian Ocean, bigeye tuna supports one of the most important fisheries in the world. This fishery mainly consists of two components: longline and purse seine fisheries. Evidence of overfishing and stock depletion of bigeye tuna calls for an evaluation of alternative management strategies. Using an age-structured operating model, parameterized with the results derived in a recent stock assessment, we evaluated the effectiveness of applying constant fishing mortality (CF) and quasi-constant fishing mortality (QCF) strategies to reduce fishing effort of purse seining with fish aggregating devices (FADs) at different rates. Three different levels of productivity accounted for the uncertainty in our understanding of stock productivity. The study shows that the results of CF and QCF are similar. Average SSB and catch during simulation years would be higher if fishing mortality of FAD-associated purse seining was reduced rapidly. The banning or rapid reduction of purse seining with FAD resulted in a mean catch, and catch in the last simulation year, higher than that of the base case in which no change was made to the purse seine fishery. This could be caused by growth overfishing by purse seine fisheries with FADs according to the per-recruit analysis. These differences would be more obvious when stock productivity was low. Transferring efforts of FAD-associated purse seining to longline fisheries is also not feasible. Our study suggests that changes are necessary to improve the performance of the current management strategy.     

近断层地震作用下基础隔震层组合限位振动台实验研究

近断层脉冲型地震作用下,基础隔震结构隔震层会产生过大变形,导致隔震支座侧倾失稳,隔震体系破坏。设计制作了3层基础隔震钢框架实验模型和11种U型钢板I型铅棒组合限位器,进行了U型钢板静力加载实验和近断层脉冲型地震作用下基础隔震层软碰撞限位振动台模型实验。实验表明：①静力加载时,U型钢板具有很好的弹性性能;②动力作用下,组合限位器残余变形较小,仍具有良好限位复位能力;③近断层地震作用下,基础隔震层软限位效果良好,同时控制上部结构层间变形在允许范围内。     

Sloped multi‐roller isolation devices for seismic protection of equipment and facilities

The rolling motion of mutually orthogonal rollers respectively sandwiched between two bearing plates in which one or both have V‐shaped sloping surfaces makes the sloped rolling‐type isolation device have an excellent in‐plane seismic isolation performance. In this study, the sloped rolling type isolation device in which a single roller moves between two V‐shaped sloping surfaces along each principle horizontal direction is refined by incorporating multi‐roller, built‐in damping, and pounding prevention mechanisms. The associated dynamic behavior is further clarified, and a simplified twin‐flag hysteretic model, which can be easily applied in most commercial computational tools is then proposed. Seismic simulation tests on the refined isolation devices (i.e. the sloped multi‐roller isolation devices) with different design parameters such as sloping angles of bearing plates and built‐in damping capabilities, together with a raised floor system by employing the sloped multi‐roller isolation devices, were conducted. Not only is the efficiency of the sloped multi‐roller isolation devices in seismically protecting the important objects, but also the practicability and accuracy of the proposed simplified numerical model in predicting the seismic responses of the sloped multi‐roller isolation devices is experimentally verified. Copyright © 2014 John Wiley & Sons, Ltd.     

一种高效率井下导线测量辅助系统

针对在煤矿井下导线和陀螺定向测量中,采用点下仪器对中操作过程往往耗时长且易造成明显的对中误差,并严重影响了矿井测量工作的效率和精度的问题,该文提出一种无需仪器精确对中的改进方法。通过安置一套测定对中偏差的触屏读数装置及内置数据处理系统,对观测数据进行自动偏心改正,较好地消减了井下导线测量或陀螺定向的对中误差影响。     

浅析国外海底取样技术的现状及发展趋势--海底取样技术介绍之一

概述了海底钻探取样在海洋油气钻井和深海科学钻探中的不同特点,指出海底钻探取样是一个前沿性的复杂课题;分析了海底取样器的分类及岩石可钻性分级;针对海底柱状取样器的科研和设计方向提出了建议。