Model tests and numerical analyses on horizontal impedance functions of inclined single piles embedded in cohesionless soil

Horizontal impedance functions of inclined single piles are measured experimentally for model soil-pile systems with both the effects of local soil nonlinearity and resonant characteristics.Two practical pile inclinations of 5° and 10° in addition to a vertical pile embedded in cohesionless soil and subjected to lateral harmonic pile head loadings for a wide range of frequencies are considered.Results obtained with low-to-high amplitude of lateral loadings on model soil-pile systems encased in a laminar shear box show that the local nonlinearities have a profound impact on the horizontal impedance functions of piles.Horizontal impedance functions of inclined piles are found to be smaller than the vertical pile and the values decrease as the angle of pile inclination increases.Distinct values of horizontal impedance functions are obtained for the ’positive’ and ’negative’ cycles of harmonic loadings,leading to asymmetric force-displacement relationships for the inclined piles.Validation of these experimental results is carried out through three-dimensional nonlinear finite element analyses,and the results from the numerical models are in good agreement with the experimental data.Sensitivity analyses conducted on the numerical models suggest that the consideration of local nonlinearity at the vicinity of the soil-pile interface influence the response of the soil-pile systems.     

地磁场时空差异对磁测精度影响

通过对辽宁地区流动地磁的观测资料进行对比分析,研究探讨了影响磁测精度的各测点与通化台之间的通化距离、经度方向距离等因素对磁测精度的影响情况。为提高流动地磁观测的磁测精度提供了参考。     

LOCAL LABOR MARKETS: THEORIES AND POLICIES IN THE U.S. DURING THE 1970s∗

Local labor market policies of the federal government are critically evaluated with respect to their target efficiency and underlying theoretical assumptions. Policies of the Economic Development Administration are considered to be target inefficient compared to those of the Comprehensive Employment Training Act. Experimental mobility policies of the Department of Labor appear to be have questionable impact locally as opposed to nationally. Some local hybrid programs offer improved place and people targeting.     

Urbanizing the periphery: infrastructure funding and local growth coalition in China’s peasant relocation programs

The Chinese State has addressed the dilemma between urban growth and farmland loss by launching mass peasant relocation programs. By moving peasants into high-rises and reclaiming their living space, arable lands are created to counterbalance the farmland loss. However, the current infrastructure funding model, which relies on local government’s bank loans, falls short of supporting the relocation programs. This paper explores this latest phase of urbanization in China by examining relocation programs in two counties in Chengdu, Sichuan and Shangqiu, Henan – before and after the transition to private investment. The paper reveals that private investors are becoming the main funders of relocation programs, and that the transition to private investment in relocation programs resulted in power reshuffle within the local growth coalition, compromises by the local government and consequently the exacerbation of peasant conditions. The paper concludes by reflecting on the social consequences of the transition, specifically benefit encroachment and risk transfer.     

Models of local governing coalitions: city politics and policy effects in Spanish municipalities

Local governance involves coalitions between public and private actors on policy issues. Actors participating in these coalitions may vary according to the issue in question, even within the same city. Based on a survey carried out among actors from different sectors of the local political community in four Spanish cities, governance networks are analyzed across five different issues: public housing, cultural tourism, urban regeneration, social policy, and citizen participation. Using network analysis and indexes in a comparative examination of 20 policy networks, we show that variations across networks are explained by policy issue content and supra-municipal regulations, regardless of the cities’ political characteristics.     

商业化大潮中丽江古城的文化特质分析

丽江旅游开发30年呈现表象的商业化与内在的文化自觉两条线索.基于访谈样本,认为丽江古城独特的地方智慧是吸引游客的主要原因,这使其呈现世界休闲古都的文化意象.最后进行两点学术讨论：（1）丽江古城遗产保护,应该兼顾物质文化遗产和非物质文化遗产.（2）丽江古城作为茶马古道的重镇,其未来的发展不应该摒弃纳西族文化、马帮文化、人-水-城-大环境四合一的中庸文化等特质,高品质的深度旅游和文化传承才是符合世界遗产旅游的潮流和可持续的.     

华南一次飑线升尺度增长过程的机制分析

利用中国自动站与CMORPH降水产品融合的逐时降水量0.1°×0.1°网格数据集、1°×1°NCEP再分析气象资料、常规观测资料和高分辨率的WRF数值模拟资料对2016年4月13日前后发生在华南的一次飑线升尺度增长过程进行了动力和热力环境条件分析。飑线形成前,对流层高层有急流,华南位于急流入口区右侧,有利于高空辐散。高空有弱槽存在,并且温度槽落后于高度槽,有利于槽发展。近地面上有低压系统控制,并且有风场的辐合,加强了抬升运动。模拟的结果表明:WRF模式成功模拟了此次飑线升尺度过程,飑线的降水量和落区较为接近实况。与以往的飑线过程相比,此次飑线过程中,升尺度阶段有效位能较初始对流阶段要高,但是整个华南地区对流有效位能始终处于中低水平。除了天气尺度系统的影响,多种中尺条件的配合对这次飑线升尺度发展很有利。低层的垂直风切变、低位涡和较高温度递减率是触发条件,提供了一定的不稳定条件和抬升条件。低层风场转向加强,垂直风切变的方向改变,充足的水汽供应和后部入流的加深加剧了不稳定和垂直抬升运动,是促进β中尺度飑线升尺度的重要条件。冷池在升尺度阶段不明显,但冷池对维持成熟阶段的α中尺度飑线结构很重要。     

Risk analysis for flood control operation of seasonal flood-limited water level incorporating inflow forecasting error

Abstract

The seasonal flood-limited water level (FLWL), which reflects the seasonal flood information, plays an important role in governing the trade-off between reservoir flood control and conservation. A risk analysis model for flood control operation of seasonal FLWL incorporating the inflow forecasting error was proposed and developed. The variable kernel estimation is implemented for deriving the inflow forecasting error density. The synthetic inflow incorporating forecasting error is simulated by Monte Carlo simulation (MCS) according to the inflow forecasting error density. The risk analysis for seasonal FLWL control was estimated by MCS based on a combination of the forecasting inflow lead-time, seasonal design flood hydrographs and seasonal operation rules. The Three Gorges reservoir is selected as a case study. The application results indicate that the seasonal FLWL control can effectively enhance flood water utilization rate without lowering the annual flood control standard.

Editor D. Koutsoyiannis; Associate editor A. Viglione

Citation Zhou, Y.-L. and Guo, S.-L., 2014. Risk analysis for flood control operation of seasonal flood-limited water level incorporating inflow forecasting error. Hydrological Sciences Journal, 59 (5), 1006–1019.     

The water balance of Lake Kyoga,Uganda

Abstract

The annual water balance of Lake Kyoga is estimated by a comparison of upstream and downstream flows in the Nile channel during a period of reliable measurements (1940–1977), supported by rainfall records over the basin. The relative contributions of net lake rainfall and tributary inflows are estimated. Changes in annual rainfall and seasonal distribution are examined.

Editor Z.W. Kundzewicz

Citation Brown, E. and Sutcliffe, J.V., 2013. The water balance of Lake Kyoga, Uganda. Hydrological Sciences Journal, 58 (2), 342–353.