关于公路与桥梁之间过渡段施工技术初探

本文主要分析了公路桥梁间过渡段出现不均沉降的原因以及公路桥梁间过渡段的施工技术的应用情况,此项技术对降低施工成本,提升桥梁的可靠性与安全性有重要作用。     

Fluid Spatial Imaginaries: Evolving Estuarial City‐regional Spaces

This article looks at successive attempts to create new spatial imaginaries around three estuary‐based city regions in England: the London–Thames Gateway, the Atlantic Gateway/Mersey Belt (Manchester and Liverpool), and Hull and the Humber ports. We develop a framework of analysis for new planning and regeneration spaces that takes forward debates on relational and territorial geographies, spatial imaginaries and the creation of new regional identities as governance objects. Specifically, we adopt a long‐term and comparative perspective that allows an examination of how successive efforts at regional building are both path‐dependent and context‐specific, as new approaches reflect emerging ideas about how best to construct successful regions in a changing global economy.     

THE FINANCIAL DEVELOPMENT AND GROWTH NEXUS: A META‐ANALYSIS

We conduct a meta‐analysis of the literature of financial development and economic growth. We cover a large number of empirical studies and estimations that have been published in journal articles. We measure the degree of heterogeneity and identify the causes of the observed differentiation. Among the most significant factors behind this heterogeneity is the choice of financial‐variable proxies, the kind of data used as well as whether a study takes into account the issue of endogeneity. Our results suggest that the empirical literature on the finance–growth nexus is not free from publication bias. Also, a genuine positive effect exists between financial development and economic growth.     

改进的沾滴法测量缓蚀剂预膜厚度

分析了传统沾滴法测量预膜厚度存在的问题,对原有的方法进行了改进,使用自制实验装置采用改进后的沾滴评价法测试分析了不同材质、不同管径管件的平均预膜厚度。结果表明,不同材质的管材表面吸附能力不同,导致管件平均预膜厚度相差较大,其中铜管的平均预膜厚度最大(0.05mm左右),碳钢管的平均预膜厚度最小(0.013mm左右);而管径对管件平均预膜厚度的影响很小。实验所得结果与同位素示踪法测定膜厚结果较吻合,从而说明改进后的沾滴评价法是一种室内评价管件平均预膜厚度的有效方法。     

Updating Input–Output Tables with Benchmark Table Series

Numerous methods have been proposed to update input–output (I–O) tables. They rely on the assumption that the economic structure will not change significantly during the interpolation period. However, this assumption may not always hold, particularly for countries experiencing rapid development. This study attempts to combine forecasting with a matrix transformation technique (MTT) to provide a new perspective on updating I–O tables. Under the assumption that changes in the trend of an economic structure are statistically significant, the method extrapolates I–O tables by combining time series models with an MTT and proceeds with only the total value added during the target years. A simulation study and empirical analysis are conducted to compare the forecasting performance of the MTT to the Generalized RAS (GRAS) and Kuroda methods. The results show that the comprehensive performance of the MTT is better than the performance of the GRAS and Kuroda methods, as measured by the Standardized Total Percentage Error, Theil's U and Mean Absolute Percentage Error indices.     

The Great Divergence: Why Britain Industrialised First

What drove the precocious industrialisation in Britain was not demand for machines but rather (as Joel Mokyr and his co-authors have argued) the supply of useful knowledge and the skills needed to put it into practice. They were the force behind early innovation. But they did not act alone. They were reinforced by British institutions, which gave the British economy a century's head start over the rest of Europe and likely too over the rich parts of Asia. The institutions included a uniform fiscal and legal system; an effective means of training apprentices, who had escaped from local guild control; and a parliament that could raise taxes and exercise eminent domain but was at the same time a credible protector of private property. Among other things, these institutions facilitated the transportation of goods such as coal and they were backed up by policies that worked in favour of manufacturing. Together, the institutions and policies generated agglomeration effects that encouraged innovation. The agglomeration effects were more pronounced in western Europe than anywhere else in Eurasia and more developed in Britain than anywhere else.     

Rank-based Tests for Cross-sectional Dependence in Large (N,T) Fixed Effects Panel Data Models

Most existing methods for testing cross-sectional dependence in fixed effects panel data models are actually conducting tests for cross-sectional uncorrelation, which are not robust to departures of normality of the error distributions as well as nonlinear cross-sectional dependence. To this end, we construct two rank-based tests for (static and dynamic) fixed effects panel data models, based on two very popular rank correlations, that is, Kendall's tau and Bergsma–Dassios’ τ*, respectively, and derive their asymptotic distributions under the null hypothesis. Monte Carlo simulations demonstrate applicability of these rank-based tests in large (N,T) case, and also the robustness to departures of normality of the error distributions and nonlinear cross-sectional dependence.     

浅谈分离式立交满堂支架的受力验算

分离式立交在工程实际中应用广泛,施工中对满堂支架的强度、刚度、稳定性的要求较高,本文以某工程为例,验算该支架能否满足工程施工的要求。