An approach to the synthesis of qualitative ecological information from aquatic coleoptera communities

A list of 196 Coleoptera taxa, larvae and adults, covering 113 species, was obtained from several surveys of a flood plain of the Rhô river. From published reports and personal experience, each taxon is linked with the modalities of nine environmental and three biological variables. The resulting 12 ecological profiles for 196 taxa are analysed by correspondence analysis. The simultaneous ordination of the taxa and variables allows presentation of the more synthetic correspondence between the Coleoptera and their ecological and biological characteristics. The niche dimensions of the 12 variables tested here are organized along a current-substrate gradient, from stones in rapid flow to mud in still water, which is associated with the other ecological conditions. This ordination reflects environmental conditions in a transverse direction, particularly from the central channel to the furthest annexes of the river. The Coleoptera are shown to be describers of the connectivity with the main channel. The 196 studied taxa are positioned along the gradient. They are subdivided into seven faunal groups based on their habitat range or niche width. The larger species are confined to the stagnant side of the gradient. Other variables, such as feeding and vertical distribution, clearly separate carnivores from herbivores and also larvae from adults. The next step of this study will be to extend these investigations to other functional variables and to all the species of Coleoptera in France. The information given by the Coleoptera will then be compared with actual field measurements.     

模糊集分析理论与我省水库汛期调度

本文针对北方干旱或半干旱地区的水库在汛期由于汛限水位的限制有水不能蓄、汛后又蓄不上水的矛盾，初步讨论了应用模糊集分析理论合理进行水库汛期调度的问题。     

Demand fluctuations and capacity utilization under duopoly

Summary.  This paper studies the impact of uncertain demand on firms’ capacity decisions when they operate in an oligopolistic environment. We define a two-stage game where firms choose capacity in the first stage without knowing which state of Nature is going to realize, and output levels in the second, knowing which state is realized. We prove the existence of a symmetric subgame perfect equilibrium at which firms are in excess capacity compared with the capacity they would choose in the Cournot certainty equivalent game. Received: May 17, 1996; revised version July 31, 1996     

河道洪水实时预报模型及在寸滩—螺山河段的应用

采用水力学和水文学相结合的方法，根据河道非恒定流的圣维南方程组，建立了河道洪水相应涨至预报模型和扩散波洪水预报模型，既可预报流量，又可预报水位。在模型的实时校正技术中，采用了具有时变遗忘因子的递推最小二乘实时校正算法，提高了参数实时跟踪能力和辨识精度。相应涨差实时预报模型和扩散波实时预报模型在寸滩－螺山河段上的应用均获得较好的效果。     

Key institutions in business and management education research

The authors investigate institutional productivity in business and management education (BME) research based on the analysis of 4,464 articles published by 7,210 authors across 17 BME journals over a 10-year period, involving approximately 1,900 schools worldwide. Departing from traditional disciplinary silos, they examine the BME research field as a whole by including all traditional business disciplinary areas and producing two top 100 rankings, one based on raw number of author publications and the other based on weighted scores reflecting journal quality and coauthorship.     

柳州市城市防洪体系及现代化建设

柳州市位于柳江中下游河段,是国家重点防洪城市,经过几年的努力,建立了工程防洪体系和非工程防洪体系,目前正在抓紧建设现代化的城市防洪体系建设。     

太原市洪涝灾害与防洪工程整治

:本文介绍了太原市的大洪涝灾害、防洪现状和存在问题 ,提出了防洪整治措施     

On some criteria for the formulation and testing of economic growth models

This paper presents a methodology for the formulation and testing of economic growth models. The model selected includes two production sectors with physical and human capital accumulation. These capital stocks are associated with spillover effects in the production of the physical good and in the accumulation of both factors.     

信江尾闾防洪对策选择

分析了梅港站多年洪水流量水位关系，得出信江尾闾相同洪水流量下水位逐年抬高的结果，通过方案比较选择了信江尾闾整治实施方案。     

Publishing performance in economics: Spanish rankings (1990–1999)

Abstract. This paper contributes to the growing literature that analyses the Spanish publishing performance in Economics throughout the 1990s. Several bibliometric indicators are used in order to provide Spanish rankings (of both institutions and individual authors) based on Econlit journals. Further, lists of the ten most influential authors and articles over that period, in terms of citations, are reported. We are grateful to many colleagues who made very useful remarks to preliminary versions of this paper, as well as to two anonymous referees. We are particularly indebted to Xavier Sala-i-Martín, without whose invaluable help this work would not have been possible. All errors or omissions are of our exclusive responsibility.