西南某水电站库区古滑坡堵江成因 及变形破坏机理研究

通过现场调查,结合边坡的地形地貌、坡体结构、变形破坏和江岸纹泥沉积特征,分析认为滑坡在变形破坏后高速下滑,撞击对岸山体并堰塞堵江,在经历长期的河湖相沉积后逐渐溢流溃决,部分滑体分别残留于左、右岸山坡上。根据恢复的原始地形,通过刚体极限平衡分析可知滑坡为地震诱发,为了进一步研究滑坡堵江成因和变形破坏机理,运用离散元数值软件进行模拟分析。研究表明天然状态下坡体浅表部沿层面和缓倾坡外优势结构面产生卸荷拉裂,地震作用使坡体内部层面拉裂并沿缓倾坡外优势结构面剪断破坏,其破坏堵江过程可概括为前缘剪切变形、后缘震动拉裂→滑面贯通、高速下滑→铲刮河床、刨蚀对岸山体→前缘受阻隆起、后缘坐落下滑、中部堰塞堵江→震后停积自稳,坡体具有明显的动力放大效应。     

重庆直辖效应评价与提升策略分析

重庆直辖已近10年，直辖效应发挥作用使生产力得到进一步解放，使重庆的经济和社会事业发生了巨大变化，使重庆人民生活水平得到了跨越式提升。在新的历史条件下，要进一步打好“直辖牌”，更好地发挥直辖效应，力争早日将重庆建设成为长江上游经济中心。     

Financial Development,Credit, and Business Cycles

How does financial development affect the magnitude of the business cycles fluctuations? We examine this question in a general equilibrium model with heterogeneous agents and endogenous credit constraints based on Kiyotaki (1998). We show that there is a hump‐shaped relationship between the degree of financial frictions and the amplification of unexpected productivity shocks. This nonmonotonic relation is due to the fall in financial frictions having two opposite effects on the response of output. One effect is the reallocation of productive inputs between agent types, which, while active, increases with the fall in financial frictions. The other effect is the change in the demand of inputs, which decreases with the fall in financial frictions. At low levels of financial development, the reallocation effect dominates and a fall in financial frictions increases the amplification of productivity shocks. In contrast, at higher levels of financial development, a fall in financial frictions decreases the shock amplification because the reallocation effect disappears while the effect on the demand of inputs is still present.     

Amplification of shocks at the zero lower bound in a small open and large closed economy

This letter compares the consequences of hitting the zero lower bound in small open and large closed economies. I show that in a large economy shocks are modified by the zero lower bound on interest rate much more than in a small one – as a result, the large economy may suffer more.     

基于EDA技术的EWB电路仿真——入门者提高分析与设计能力的基础

通过EWB电路仿真,将理论电原理图用直观的测量仪器仪表演示。体现出在合理可行的电路结构下的参数,也可进行相应的指标调试,得到最佳的工作状态。辅助抽象理论学习,系统掌握体系中的知识点,过程实现简洁,效果明显,引发自我学习兴趣。本文展开的分析仿真为初学者自学和后期深入EDA技术领域打下基础,拓宽思路,为分析与设计能力的提高做好铺垫。     

高陡边坡地震动放大效应分析

为了研究高陡岩质边坡对地震动加速度峰值的放大作用,分别针对简谐波和El Centro波竖向入射高陡边坡的情形,基于动力学模拟研究了坡肩和坡表面放大系数与坡高和坡比的参数关系。根据计算结果绘制边坡剖面的水平向和竖向放大系数等值线图,分析了坡体内放大系数分布特征。结果表明放大系数并不随着坡高的递增而持续增大,放大系数的最大值出现在坡肩,在不超过2.0的范围内波动变化。坡顶面上的放大系数随着坡肩距的增大而逐渐衰减。坡体内水平向与竖向放大系数的空间分布特征显著不同,在邻近坡肩和斜坡面的区域内竖向放大系数可高达1.5,高陡边坡的抗震设计中不可忽略竖向放大系数的影响。     

The default contagion of contingent convertible bonds in financial network

This paper investigates the impact of contingent convertible (CoCo) bonds on systemic risk using Eisenberg-Noe’s financial network method, in which the network is linked by debt relationships. As an efficient method for addressing the problem of “too big to fail,” CoCo bonds have received widespread attention, particularly because the trigger for CoCo bonds is a systemic risk event. Thus, the impact of CoCo bonds on systemic risk needs to be addressed. To solve this problem, we adopt default contagion and loss amplification due to network linkage to measure systemic risk, from which we can ascertain the potential impact on it of CoCo bonds. The results show that CoCo bonds enhance the spillover effect of the issuer’s default; meanwhile, sufficient CoCo bonds partly offset the impact of default contagion from other banks. Furthermore, CoCo bonds enhance the amplification effect of loss due to network linkage, but the amplification effect diminishes after the bankruptcy cost is considered. Finally, the numerical test provides some insight into how the issuance of writedown (WD) bonds influences commercial banks in China. Our study not only offers suggestions to the regulators of CoCo bonds but also contributes to related studies.     

地震波斜入射下深厚覆盖层河谷加速度分布特征分析

我国西部地区普遍具有高山峡谷和深厚河床覆盖层的特点,而对于深厚覆盖层河谷场地的地震动分布特征的研究却很少。本文采用黏弹性人工边界及其相关地震动等效荷载输入的方法,研究了地震动P波和SV波入射角度及入射波峰值对深厚覆盖层河谷场地加速度放大系数分布特征的影响。结果表明：（1） P波和SV波入射角度一定时,入射波峰值对河谷两岸平台及岸坡的加速度放大系数影响很小;（2） P波左侧入射时,随着入射角度的增大,左岸平台及岸坡x分量的加速度放大系数增幅较大,z分量的加速度放大系数增幅较小保持在2倍左右,河谷覆盖层表面x和z分量加速度放大系数逐渐趋于均匀分布;（3） SV波左侧入射时,随着入射角度增大,整个河谷覆盖层表面x分量的加速度放大系数呈现出坡脚附近较小,中间部位和两岸平台较大;z分量放大系数呈现出相反的规律。这些结论可以为具有覆盖层河谷工程场址的地震动参数设计及加速度监测点布置提供一定的参考。     

通过流量放大减小水文模拟与预报不确定性的应用研究

应用TOPMODEL模型,采用普适似然不确定估计(GLUE)方法,以属于半干旱地区的东湾流域为例,探讨径流系数在水文模拟与预报中的影响作用。通过其影响来提高径流系数较低地区的模拟精度,减小水文模拟与预报的不确定性。研究发现,模拟精度随着径流系数增大而提高,并在径流系数为0.5附近达到峰值后逐渐降低。基于此通过流量放大的改进方法进行东湾流域的水文模拟,改进后的结果有较大改善。     

不同订货周期的零售商最优订货策略研究

企业联盟是企业间“合作-创新”的一种组织创新。企业加入联盟后能够获得新的竞争优势。但是,和其他组织形式相比,企业联盟并不具有绝对的优势。在不同的条件之下,企业会选择最适合它的行动方式。为了保证企业联盟能够顺利组建并运行,各成员在参加联盟后所获得的收益要超过它因参加联盟所发生的费用。