L形截面短肢剪力墙抗震性能的模型试验研究

为了研究L形截面短肢剪力墙的抗震性能,对6个1/2缩尺比例的L形截面短肢剪力墙试件进行了低周反复荷载作用下的试验研究,分析了轴压比、截面高厚比、剪跨比等参数变化时,对试件的承载力、延性、滞回特性、耗能能力及破坏特性等抗震性能的影响。结果表明:L形截面短肢剪力墙试件扭转变形较小,试件以弯剪破坏为主,腹板底部为试件最薄弱部位,剪跨比小,轴压比大的试件腹板中心剪切破坏现象明显;试件随着截面高厚比、轴压比的提高,极限承载力增加,试件耗能能力变差、延性下降明显;L形截面短肢剪力墙试件在截面高厚比适中,为6.5∶1时,经济、抗震性能也较好。     

地震波动力学特征变化指标在短期地震预报中的应用

本文研究了地震前地震波动力学特征的变化，主要是波形和频谱的变化，并从中提取出可望在短期（半年以内）地震预报中应用的一些预报指标。这些指标包括：Ｐ波初始部分波形的时间线性度和空间线性度，初始段平均半周期，Ｓ，Ｐ波频谱的峰值频率，拐角频率，相对带宽度，相对频谱峰值，高频段的谱线斜率绝对值等。同时还研究了短周期地脉动的波形线性度及频谱特征量（峰值频率等）在大震前出现的短期（半年以内）和临震（９天以内）的     

基于12322平台的江苏省地震应急灾情速报系统的设计与应用

通过分析地震应急救援工作中对灾情信息的需求,提出了“地震应急灾情”的概念,设计了基于12322平台的江苏省地震应急灾情速报系统。本文详细介绍了该系统的设计框架、基本功能和应用效果。系统主要包括短信和微信两大模块,短信模块主要面向非地震系统人员,通过手机短信形式向社会灾情速报员发送灾情邀请短信,灾情速报员只需简单回复灾情代码“1”—“4”即可。微信模块主要面向地震系统工作人员,通过微信企业号“苏震12322”自动推送地震信息并完成灾情收集工作。经过近1年的试运行,系统能够在震后迅速完成灾情信息的收发与数据处理工作,并以“天地图”为地理底图实时直观地展示已上报的灾情信息。     

短期气候预测的评估问题

该文系统地介绍了国内外评估月、季尺度短期气候预测结果的方法 ,比较了相关系数(R)、预报技巧分 (S)和准确率 (P)的特点 ,并对当前国内外气候预测业务水平进行了分析 ,着重对大气环流、气温、降水及 ENSO的预测水平进行了评估 ,指出国内外月、季尺度的降水预报的水平目前在 55%～ 60 %左右 ,对 ENSO的发生、结束和强度的预报水平有限 .文中探讨了短期气候预测的可预报性问题 ,提出月、季尺度气候预测的可预报性的理论上限可能为 6～ 1 2月 ,准确率在 80 %～ 85%之间 .     

GNSS变形监测网短基线时间序列噪声特性分析

利用时间跨度为5 a的GNSS短基线时间序列对噪声特性进行分析,发现长周期噪声分量(随机游走噪声)。选取最优噪声模型,评估不同噪声模型对测站周期振幅和线性速度估值的影响。结果表明,短基线时间序列中有色噪声应顾及闪烁噪声和随机游走噪声,对于表现出随机游走噪声的分量,可能与测站的真实运动有关;假设只有白噪声时求得的速度估值与最优噪声模型下求得的速度估值存在0.4～0.6 mm/a的偏差,对周期振幅的影响可以忽略。     

奥运短时临近预报实时数据处理

详细分析了目前短时临近预报系统对自动气象站数据质量控制、探测数据更新频率、组网雷达时间同步观测与基数据实时传输、探测数据的实时传输技术、基于目录监控的数据监控与分发机制、基于开源的软件开发、数据格式等方面的需求.在此基础上,建立了北京奥运短时临近预报数据快速收集处理系统并已经投入业务运行,该系统实现了探测数据的实时传输、组网雷达时间同步观测和基数据实时传输、基于消息驱动的数据实时监控和分发、探测数据格式规范化等功能,基本满足北京2008年奥运短时临近预报系统的数据预处理业务需求.     

PMODTRAN: a parallel implementation based on MODTRAN for massive remote sensing data processing

MODerate resolution atmospheric TRANsmission (MODTRAN) is a commercial remote sensing (RS) software package that has been widely used to simulate radiative transfer of electromagnetic radiation through the Earth's atmosphere and the radiation observed by a remote sensor. However, when very large RS datasets must be processed in simulation applications at a global scale, it is extremely time-consuming to operate MODTRAN on a modern workstation. Under this circumstance, the use of parallel cluster computing to speed up the process becomes vital to this time-consuming task. This paper presents PMODTRAN, an implementation of a parallel task-scheduling algorithm based on MODTRAN. PMODTRAN was able to reduce the processing time of the test cases used here from over 4.4 months on a workstation to less than a week on a local computer cluster. In addition, PMODTRAN can distribute tasks with different levels of granularity and has some extra features, such as dynamic load balancing and parameter checking.     

全站仪近距离测距精度检验方法的探讨

提出了室内基线法，给出了相应的数据处理方法，并用实测数据进行了计算，结果显示全站仪在室内、短边条件下的测距精度较标称精度有很大的提高。该法所得结果与现存两种方法的结果基本相当，从而证明了该法能够客观地反映出工业测量用全站仪的近距离测距精度。     

天津地区井水位年变异常研究

近年来 ,中国地震预报学者开始关注井水位的年变异常及其中短期预测意义问题 ,但井水位年变异常判别采用动态图像的定性对比方法 ,表现出一定的随意性。针对这种现状 ,文中引进概率论与数理统计中的随机过程理论与时间序列分析技术 (盛骤等 ,1989) ,提出了“井水位动态年周期法”与“相对时段速率比较法” ,解决了井水位年变异常的定量识别方法 ,并应用到天津井网 2 1口井的观测数据 (1985年以来 )分析中 ,证明了该方法的可行性与有效性。分析结果表明 ,天津井网中有 7口井在首都圈邻区 4次中强 (MS≥ 5 .8)地震之前 ,表现出 17井次的井水位年变异常 ,且多在震前 1.5～6个月内出现 ,从而再次证明了井水位年变异常具有一定的中短期预测意义     

Escaping the climate policy uncertainty trap: options contracts for REDD+

Climate policy uncertainty significantly hinders investments in low-carbon technologies, and the global community is behind schedule to curb carbon emissions. Strong actions will be necessary to limit the increase in global temperatures, and continued delays create risks of escalating climate change damages and future policy costs. These risks are system-wide, long-term and large-scale and thus hard to diversify across firms. Because of its unique scale, cost structure and near-term availability, Reducing Emissions from Deforestation and forest Degradation in developing countries (REDD+) has significant potential to help manage climate policy risks and facilitate the transition to lower greenhouse gas emissions. ‘Call’ options contracts in the form of the right but not the obligation to buy high-quality emissions reduction credits from jurisdictional REDD+ programmes at a predetermined price per ton of CO₂ could help unlock this potential despite the current lack of carbon markets that accept REDD+ for compliance. This approach could provide a globally important cost-containment mechanism and insurance for firms against higher future carbon prices, while channelling finance to avoid deforestation until policy uncertainties decline and carbon markets scale up.

Key policy insights

• Climate policy uncertainty discourages abatement investments, exposing firms to an escalating systemic risk of future rapid increases in emission control expenditures.

• This situation poses a risk of an abatement ‘short squeeze,’ paralleling the case in financial markets when prices jump sharply as investors rush to square accounts on an investment they have sold ‘short’, one they have bet against and promised to repay later in anticipation of falling prices.

• There is likely to be a willingness to pay for mechanisms that hedge the risks of abruptly rising carbon prices, in particular for ‘call’ options, the right but not the obligation to buy high-quality emissions reduction credits at a predetermined price, due to the significantly lower upfront capital expenditure compared to other hedging alternatives.

• Establishing rules as soon as possible for compliance market acceptance of high-quality emissions reductions credits from REDD+ would facilitate REDD+ transactions, including via options-based contracts, which could help fill the gap of uncertain climate policies in the short and medium term.