Firm-level interactions between exporting and productivity: Industry-specific evidence

This paper investigates interactions between exporting and productivity at the firm level, using a panel of firms in the UK chemical industry. This is both highly technology intensive and the UK’s largest exporting sector. We find exporters are more productive than non-exporters, but are also on average smaller. This superior productivity performance among exporters appears to be caused by both self-selection and learning-by-exporting effects. In contrast to other studies, we find learning effects are significantly positive among new entrants, weaker for more experienced exporters and negative for established exporters. JEL no. F14, D21, L65     

Flood frequency and routing processes at a confluence of the middle Yellow River in China

Floods cause environmental hazards and influence on socio‐economic activities. In this study, we evaluated the historic flood frequency at a confluence in the middle Yellow River, China. A non‐parametric, multivariate, empirical, orthogonal function matrix model, which consists of time correlation coefficients of flood discharge at different gauge stations and flood events was used for the analysis of flood frequency. The model addresses the characteristics of confluent floods such as frequency and the probability in multiple tributary rivers. Flood frequency analysis is often coupled with studies of hydrological routing processes that reduce the flood capacity of the rivers. Flood routing to the confluence were simulated using kinematic wave theory. Results of this flood frequency analysis showed that flooding frequency has intensified in the past 500 years, especially during the 19th century. Flooding in streams above the confluence was more frequent than in streams below the confluence. Over the last 2000 years, concurrent flooding in multiple tributary rivers accounted for 67.5% of the total flooding in the middle Yellow River. Simulation of flood routing processes shows that the decreased flooding capacity and elevated river bed of the shrunken main channel leads to an increased flood wave propagation time (24–52.3 h) in the study area after 1995. The model indicates that human activities, such as constructions of the Sanmenxia Dam, have changed flood routing boundary conditions and have contributed to the increased flood frequency at the confluence. Copyright © 2007 John Wiley & Sons, Ltd.     

浅谈昌图县水土流失治理措施及其监督管护

本文通过对昌图水土流失的成因分析,根据各地的实际情况划分了重点预防保护区、重点监督区、重点防治区来进行治理,并提出了治管兼治的治理方法,使昌图县水土流失得到有效控制。     

皂河闸小水电存在问题及改造探讨

针对皂河闸水电站因长期运行造成的机电设备老化、机组效率较低等问题,对3号机进行技术改造。经过调研分析,提出改造方案,并对改造前后的经济效益进行对比分析。表3个。     

Development,construction, and use of pneumometric tubes for measurement of steam flow in the steam lines of PVG-1000 at NPP

A system for the direct measurement of steam flow in steam lines after a steam generator, which utilizes a special design of pneumometric tubes and a computing unit that accounts for variation in steam pressure, has been developed to improve the quality of water-level regulation in the steam generators of VVéR-1000 power-generating units in the stationary and transitional modes. The advantage of the pneumometric tubes consists in their structural simplicity, high erosion resistance, and absence of irrevocable losses during measurement of steam flow. A similar measurement system is used at foreign NPP. The measurement system in question has been placed in experimental service at the No. 3 unit of the Balakovo NPP, and has demonstrated its worthiness. This measurement system can also be used to determine steam flow in the steam lines of NPP units with VVéR-1000 and VVéR-440 reactors, and PBMK-1000 power-generating units. __________ Translated from élektricheskie Stantsii, No. 3, March 2007, pp. 23–26.     

Strategy for olive mill wastewater treatment and reuse with a sewage plant in an arid region.

This study was conducted to evaluate the treatability of OMW (olive mill wastewater) with sewage and sewage sludge, which could supplement nutrients and microbes required for OMW treatment and reduce its possible toxicity. The amount of OMW added to an aeration tank was based on the loading difference between the designed and actual COD loads, while the amount added to anaerobic digestion for energy recovery was determined by CH4 production. The COD removal efficiencies were 70-85% for both systems. Compost of OMW with dried sewage sludge also showed a similar temperature profile without OMW addition. This strongly suggested that OMW can be treated at a sewage plant without pretreatment and the treated effluent can be reused in irrigation for an arid region.     

中国证券市场有效性研究

本文对有效市场理论进行了简单的阐述,研究了我国证券市场有效性的现状,对中国证券市场有效性的实证研究及检验成果进行了总结评述,分析了中国证券市场有效性欠佳的主要原因,提出了增强证券市场有效性的对策和建议。     

保健酒营销牌如何打

<正>保健酒市场是个独具特色,细分了的个性市场。产品游戈在保健品和白酒之间,并寻求差异化的推广。代表品牌有椰岛鹿龟酒、湖北劲酒、致中和五加皮等。在市场运作策略上,他们要么走餐饮线,要么走送礼线。不过前者显得传统、中规中矩,后者凸现时尚求变、求活特征。探究两者之间规律性的东西,基本上比拼策略,除了品牌、实力     

PLC在葛洲坝大江电厂机组辅助设备控制中的应用

PLC(可编程控制器)在机械工业和电力生产等部门应用广泛。在电力生产部门主要用于集中控制,已有较好的效果。介绍了PLC在葛洲坝水电厂机组辅助设备控制操作功能中的应用回顾及其展望。     

人才强国,关键在于培养和使用好人才

我国是一个人口大国，如何将我国的人口负担转化为人才资源优势，这是党和国家建设事业的关键问题。笔者认为人才强国战略的实施，关键在于培养和使用好人才，在于快出人才，多出人才和出好人才。为此，文章提出了一些人才使用的策略。