灌溉泵站设计参数的确定及水泵选型

水泵选型是泵站工程设计中的重要问题,选型合理与否,直接关系到泵站工程的投资、建成后的运行费用和供水安全.水泵选型必须根据工程具体情况,确定合适的水泵型号和台数.选型的基本依据是泵站工程规划中所确定的设计参数,即所在泵站的流量、扬程及其变化规律.本文对灌溉泵站的设计参数确定及水泵选型问题进行了讨论,提出了设计参数的确定及水泵选型的方法.     

2-D NUMERICAL SIMULATION OF FLOODING EFFECTS CAUSED BY SOUTH-TO-NORTH WATER TRANSFER PROJECT

Since the General Channel designed for the South-to-North Water Transfer Project in China has to cross many rivers and streams flowing from west to east, there are potentially serious effects additional flooding on the western side of the project alignment. Therefore, a 2-D numerical model for forecasting basin flood disasters was established and verified using historical flood data. The model was applied to researching the interaction between the proposed Project and flooding events for 5 streams in the Anyang River reach as a representative case study. Simulated results indicate that the model could correctly forecast the flood, submerged area and depths, and water surface elevations along the left side of the channel. The discharge capacity and location of hydraulic structures in the transfer canal alignment were analyzed. Then adjustments to the dimensions and positioning of proposed hydraulic structures were recommended at intersections, especially the addition of a channel to transfer flood water from one stream to another, which can effectively limit the sluice and protect the Anyang City from flooding.     

承压含水层非稳定流拉普拉斯变换有限层分析

以有限层法为基础，利用拉普拉斯变换，将时间域上的地下水非稳定流的问题转化到拉普拉斯域求解,提出了求解地下水三维非稳定流的拉普拉斯变换有限层法，建立了拉普拉斯空间中的有限层方程，在求得拉氏空间解的基础上，利用Stehfest数值逆变换方法实现了一步求解给定时刻任意位置的地下水降深。在数值算例验证本文方法的正确性的基础上，讨论了Stehfest数值逆变换中计算项数K的合理取值和计算参数对K取值的影响。本文方法不仅具备将三维问题简化为一维问题求解的优点，而且克服了传统数值方法只能对离散点分别进行数值逆变换的局限性，进一步提高了计算效率。     

微电子机械系统ADXL345的应用研究

微电子机械系统因其成本低、可靠性高、功耗低、体积小和重量轻等特点,在便携式电子设备中应用广泛。文章通过S3C2440针对美国ADI公司最新推出的三轴数字加速度计ADXL345进行运动特性的检测研究,为该器件的应用开发提供了一种方法。     

复杂河口汊道封堵水沙问题研究

摘 要：对复杂分汊河口次要汊道进行封堵围垦可以获得土地资源。以瓯江口南口封堵为例研究了复杂河口汊道封堵问题。首先对复杂的瓯江口的自然条件和冲淤演变进行了分析；其次，使用二维波浪潮流泥沙数学模型、波浪潮流泥沙物理模型及三维潮流数学模型等研究手段，对瓯江南口现潜堤加高进行了封堵后的二维潮流场、泥沙场、地形冲淤变化和三维潮流场进行了模拟研究，对瓯江泄洪排涝的影响进行了计算和分析。研究结果表明，从对周围水沙环境和瓯江泄洪排涝的影响角度考虑，将现潜堤加高进行南口封堵的方案是可行的。     

3PL企业作业流程配送处理分析

3PL企业在我国的发展越来越迅速。在3PL企业中作业流程中配送系统占据了重要的地位，文章详细的分析了3PL配送系统流程，有利于提高企业作业效率，产生巨大的经济价值。     

以制度改革推进城乡一体化进程

根据刘易斯二元经济理论，推进城乡一体化的关键是实现人口在城乡和地区间的自由流动，而在我国，限制和阻碍人口流动的主要是制度因素，制度上的二元结构阻碍了经济二元结构一元结构的转换。从这个意义上讲，城乡一体化的推行意味着一场新的制度改革和制度创新的到来。这就要求我们在推进城乡一体化的过程中，一方面必须紧紧抓住制度创新和改革这一牛鼻子；另一方面，必须尊重经济发展规律，因地制宜，切忌盲目跃进；还要尊重农民意愿，而不可由政府越俎代庖。     

WHAT MAKES A GREAT JOURNAL GREAT IN ECONOMICS? THE SINGER NOT THE SONG

Abstract This paper analyses what makes a great journal great in economics. Alternative research assessment measures (RAM) are discussed, with an emphasis on the Thomson Reuters Institute for Scientific Information (ISI) Web of Science database. ISI RAM that are calculated annually or updated daily are defined, including the classic 2‐year impact factor (2YIF), 5‐year impact factor (5YIF), immediacy (zero‐year impact factor (0YIF)), eigenfactor score, article influence, citation performance per paper online, h‐index, Zinfluence, PI‐BETA (papers ignored ‐ by even the authors) and two new RAM measures, self‐citation threshold approval rating and impact factor inflation. The data are analysed for the most highly cited journals in economics, management, business and business–finance on the basis of 2YIF. In addition to evaluating research in the most highly cited journals in economics, management, business and business–finance, the paper evaluates alternative RAM, highlights similarities and differences in RAM criteria, finds that several RAM capture similar performance characteristics, and finds that immediacy and PI‐BETA are not highly correlated with other RAM. Harmonic mean rankings of the 12 RAM criteria are also presented. Emphasizing 2YIF to the exclusion of other useful RAM criteria can lead to a distorted evaluation of journal performance and influence.     

多沙水库准二维泥沙数学模型

本文介绍了作者提出了的水库泥沙数学模型，在该模型建立过程中，引入了水流挟沙力统一公式，泥沙级配计算公式，异重流运动最新成果和因考虑异质粒子与紊流场相互作用而给出的泥沙运动修正方程等，初步验算结果表明，本水库数学模型具有很强的适应性和模拟功能。     

从金融危机看宏观型对冲基金的本质

国际资本自由流动是宏观型对冲基金的温床。尽管国际上受美金融危机发生的具体原因千差万别,但共同的特点是有意、无意地扩大宏观经济基本面的失衡,然后借助金融市场的瞬间强制调整,获取巨额利润。宏观型对冲基金作为盈利组织无可厚非,关键是要避免宏观经济的严重失衡。