高墩悬臂牛腿设计与施工

本文根据沪昆客专跨河大跨度连续梁高墩0#块施工作为背景,结合0#块现浇牛腿的设计与施工,优化常规设计,达到安全可靠,节约成本的的目的,可为同类型施工提供参考。     

Diversification strategy with random yield suppliers for a mean–variance risk-sensitive manufacturer

We consider the diversification strategy for a mean–variance risk-sensitive manufacturer with unreliable suppliers. We first analyze the linear model and find that the suppliers are selected according to the descending order of their contributed marginal expected profit, and increasing the manufacturer’s risk-averseness leads to a more even allocation of demand across the suppliers. Then, we study the general newsvendor model. By approximating the leftover inventory with a normal distribution, we establish the general properties of the active supplier set and show that the supplier selection rule is similar to that under the risk-neutral setting when the demand uncertainty is large. Moreover, we conjecture that the selection rule also applies when the demand uncertainty is low, which we verify with an extensive numerical study. Our paper makes two contributions: First, we establish the properties of the optimal diversification strategy and develop corresponding insights into the trade off between cost and reliability under the mean–variance framework. Second, we perform comparative statics on the optimal solution, with a particular emphasis on investigating how changes in the supplier’s cost or reliability affect the risk-averse manufacturer’s ordering decisions and customer service level.     

Kernel-type estimators for the distortion risk premiums of heavy-tailed distributions

A new kernel-type estimator for the distortion risk premiums of heavy-tailed losses is introduced. Using a least-squares approach, a bias-reduced version of this estimator is proposed. Under suitable assumptions, the asymptotic normality of the given estimators is established. A small simulation study, to illustrate the performance of our method, is carried out.     

The effectiveness of the ECB’s unconventional monetary policy: Comparative evidence from crisis and non-crisis Euro-area countries

During the European financial crisis, the European Central Bank implemented a series of unconventional monetary policy measures. We argue that these programs lowered the bond yield spreads of Euro-area countries. This hypothesis is tested using pooled OLS estimations and two different datasets: monetary policy event dummies and the purchase volumes of the Securities Markets Programme (SMP). Overall, we find significantly negative effects on bond yield spreads for both datasets, leading us to accept the hypothesis. While the OMT reduces the spreads of both crisis and non-crisis countries, LTROs and the lowering of the deposit rate to 0 percent are mainly effective in non-crisis countries. The SMP lowers the spreads of crisis countries, but it has the opposite effect on non-crisis countries. This converse effect is explained by the risk that increasingly accumulates on the ECB’s balance sheet through the SMP and that way constitutes a fiscal risk for non-crisis countries. The results are confirmed by pooled OLS estimations that measure the effect of unconventional monetary policy on central government debt.     

The High‐Rise Home: Verticality as Practice in London

This article investigates the relationship between verticality and home. It develops the idea of ‘verticality as practice'. This appreciates verticality not as something that takes place in three‐dimensional landscapes, but as the outcome of everyday practical activity. Examining a modernist high‐rise estate, the Aylesbury Estate in London, the article identifies and examines a range of vertical practices, illustrating how they are intertwined with home. Vertical practices, such as those associated with the view, help to make a unique and special home, becoming intensely meaningful to residents. However, they also unmake dimensions of home when they interact with the estate's marginality.     

高压变频器在电厂凝结水泵上的应用

文章论述了高压变频器在燃煤发电厂大容量电动机上应用的必要性,介绍了凝结水泵的变频改造方案,分析了高压变频器改造的经济性,为同类型发电厂的节能降耗提供了借鉴经验和参考。     

Promoting Giving Campaigns in University Websites: A Cross-cultural Comparison between the United States and South Korea

ABSTRACT

This study was designed to compare the ways the websites promote giving campaigns between the United States and South Korea. Furthermore, this study explored how the campaign appeals are associated with the distinct cultural values between universities in the United States and Korea. Guided by a content analysis of 200 universities in the United States and South Korea, the findings of this study demonstrated that, compared to the Korean university websites, U.S. university websites more frequently targeted university-affiliated donors, including alumni, students, parents, and so forth, and used multimedia-based exemplars about the giving campaigns.     

逆比较优势进口高技术含量中间品与生产技术革新

科学刻画逆比较优势进口高技术含量中间品对生产技术革新的影响效应能为制定科学进口国外中间品和提升生产技术革新速度方面的政策提供有益参考,以剖析上述效应为目标的多维细致检验结果表明：首先,制造型和服务型中间品进口技术含量逆比较优势指数对生产技术革新的影响效应呈现倒U型,进口约2.5倍于自身比较优势水平技术含量的中间品能最大化中间品进口的生产技术革新功能,这一结论在多层面检验中均稳健成立。其次,中国中间品进口技术含量逆比较优势指数处于倒U型顶点的左侧正效应区间。对于动态比较优势持续提升的中国而言,在处理好“卡脖子”风险的基础上,可适度提升中间品进口技术含量,以更好地发挥中间品进口的生产技术革新功能。最后,倒U型效应具有非常强的稳定性,多维外部冲击均无法撼动倒U型效应。为此,倒U型效应可谓协调中间品进口和生产技术革新间关系的“铁律”。     

基于网络处理器IXP2400的组播包高速转发技术

传统的IP报文的组播技术,由于在处理过程中需要把整个报文的内容报文复制多份,因此处理器需要对缓存报文的外部存储空间进行多次I/O操作,这严重制约了当前处理器,特别是网络处理器的高速报文处理能力,转发效率不高.为此,提出了一种新的技术--"零拷贝"转发技术.该技术只修改报文头,报文体不复制,减少了大量的I/O操作,提高了转发效率.     

一种资产定价过程中跳辨识的新方法

文章主要基于AitSahalia(2002)关于金融数据中跳(Jump)的研究,对跳的性质作进一步的探索并加以推论,同时采用IMSE(InferiorMeanSquaredError)作为分离跳的标准,选择出恰当的(λ,α,Δ)仨,达到辨识金融数据中跳的目的。