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61.
陈立琼 《中国水运》2007,7(2):198-200
我国资本市场股权分置改革基本完成。这就要求上市公司在全流通后的财务报告及信息披露将更为完善。本文分析了目前我国上市公司的财务报告及信息披露存在的问题,对规范上市公司会计信息披露提出了对策:上市公司不仅需要提供公司的财务信息,而且需要提供公司治理、内部控制、风险控制、社会责任等相关情况,并从企业内部监管、法律监管、社会监管等方面规范上市公司的会计信息披露。  相似文献   
62.
Satellite images of surface chlorophyll-a concentration measured by the sea-viewing wide field-of-view sensor (SeaWiFS) and of sea surface temperature derived from advanced very high resolution radiometer (AVHRR) measurements, combined with in-situ drifter measurements of surface currents, and ancillary wind, Po River discharge and surface salinity data, are used to describe the surface dynamics in the northern Adriatic during the period September–October 1997.The satellite observations revealed very complex mesoscale dynamics, with time scales of a day or two and length scales of about 10 km, including the meandering and instability of basin-scale currents (e.g., the western coastal layer), jets/filaments and eddies. In addition, the two typical patterns of the Po River plume are observed and qualitatively explained in terms of wind forcing. A basin-wide double gyre pattern spreads the rich runoff water across most of the northern Adriatic from mid-September to early October, following Bora wind events and under stratified sea conditions. In contrast, in late October the Po plume is confined to the coast due to weaker winds and de-stratified conditions. This variability in the Po River plume extension is also confirmed by in-situ salinity measurements.  相似文献   
63.
A two-dimensional hydrodynamic and sediment transport models have been developed and applied to the Ria de Aveiro lagoon, Portugal. The application consisted in the study of the residual circulation, the residence time as well as the sediment dynamics in the lagoon. High residence time for particles situated at the far end of the main channels points out that they are retained for a long time and tend to remain there, with high probability of being deposited into the bed. Low residence time for the central areas implies that the particles are flushed out more rapidly toward the lagoon mouth, revealing that the water and the particles exchange are very effective there. Although the residual circulation due to the rivers induces an overall transport toward the lagoon mouth, the residual circulations due to the winds induce particular circulation patterns (clockwise or counter-clockwise eddies) at some locations of the lagoon, depending on the wind direction. It was found that the suspended sediment concentrations along the main channels are induced by tidal asymmetries (resulting in areas of ebb and flood dominance), as well as by the wind stress and rivers runoff effects. They contribute, in general, to increase the sediment export toward the ocean, although the wind stress may induce currents and circulations in the opposite direction of the tidal currents. High turbid zones are observed for strong tidal currents, associated with tidal asymmetries, as well as with high rivers runoff. The erosion–deposition budget indicates a tendency for sediment accumulation at important areas of the lagoon, namely the shallow ones.  相似文献   
64.
Variability of river plumes off Northwest Iberia in response to wind events   总被引:4,自引:0,他引:4  
The Western Iberian Buoyant Plume (WIBP) is a low-salinity lens formed by river discharge and continental run-off extending along the shelf off Northwest Iberia. The variability of this structure is evaluated with a numerical model forced by real meteorological data and climatologic river discharge during late 2002, when conditions were those of a typical autumn. The direction and intensity of the wind-induced Ekman transport, but also the previous conditions and the duration of the event are found to determine plume behavior. We have identified three characteristic situations: a) confinement of the plume to the coast during downwelling — southerly-winds, b) expansion of the plume during the declining phase of the downwelling event by relaxation of the wind, and c) expansion of the plume by upwelling — northerly-winds. The short time scale of the response of the plume (1–3 h) adds timing between wind events and the phase of the tide as an additional source of variability. In all cases the Iberian Poleward Current (IPC), a saltier and warmer poleward current flowing over the slope, responds as well to wind changes. Furthermore, our simulations illustrate how topography and differences in the river discharge induce local differences in dynamics. Comparisons to available observations show a reasonable model skill. Differences between wind measurements and wind forcing applied to the model appear to be a major source of uncertainty in model results.  相似文献   
65.
研究了低阶大气环流模型的稳定性和分岔性质.用李亚普诺夫方法和定性理论分析了模型的稳定性,证明了全局一致渐进稳定和极限环的存在性,并给出了低阶大气环流模型的分岔条件.此外,研究了模型的Hopf分岔,并用规范形理论得到了Hopf分岔临界状态,最后运用数值仿真对所给的定理和条件进行了验证.  相似文献   
66.
统筹城乡发展、加快形成城乡经济社会一体化新格局破解城乡二元结构的重要举措。实现城乡统筹发展必须从破解制约城乡统筹发展的瓶颈因素—农村土地流转这个难题入手,分析影响农村土地流转的因素。在土地流转的背后,深层次的问题是如何平衡土地流转中的多边利益,实现农民对土地财产权的价值,让农民以土地的权利参与城市化,形成合理的利益分配格局,推动城乡统筹发展。  相似文献   
67.
陈海江  刘鹤 《船舶工程》2021,43(2):150-153
针对现有钻井平台泥浆系统存在的大袋漏斗泥浆混合效率低且易堵、水基泥浆和油基泥浆排渣通道不独立、泥渣输送/排渣效率低以及开展泥浆循环试验时无法建立完整的试验回路等问题,以CJ46型自升式钻井平台泥浆系统为例,分析其在设计、调试和使用过程中存在的主要问题,在此基础上提出优化设计方案.通过对泥浆系统中的泥浆混合系统、泥浆处理系统以及泥浆循环试验中用到的装置和系统进行优化,改善整个泥浆系统的性能,为功能相近的钻井平台泥浆系统的优化设计提供参考.  相似文献   
68.
铁路信息系统故障处理联动平台规避了传统信息系统故障处理不能够全过程实时掌控的弊端,实现了故障处理有时间、有记录、有结果、有反馈的严格闭环管理.设备资源管理模块实现了每一套信息系统档案健全、透明公开、实时检索,大大提高了信息系统故障处理效率.知识库、经验库模块起到了技术交流的作用,为新职工搭起快速学习的桥梁,也为各业务系统之间搭建起快速协作的通道,确保铁路运输工作的安全稳定.  相似文献   
69.
随着工业化与城镇化的快速推进,土地流转过程中产生了大量的被征地农民。由于法律规定不完备、补偿标准偏低、以及残缺的农村社会保障制度等原因,导致了被征地农民的利益缺失,给经济持续稳定发展和现代化建设带来了不同方面、不同角度的影响。本文通过分析被征地农民面临的困境及原因,指出其对经济长期增长的影响,最后得出完善土地征用制度、建立合理的社会保障体系、大力解决农民失地后的再就业问题等结论。  相似文献   
70.
杨志君 《水运工程》2012,(8):187-190
在板桩码头设计中,为了减少土压力对板桩的作用,常在板桩后面一定距离设计一排遮帘桩。常用的遮帘桩有:预制混凝土桩、钢管桩和灌注桩,其中灌注桩是常用的一种。通过计算得出:灌注桩的截面为矩形比圆形遮帘效果好,但矩形截面的灌注桩采用常规施工机具成孔效率低,且很难保证桩孔质量。介绍采用经过改造后的多头钻气举反循环成槽施工工艺和设备,施工效果良好。  相似文献   
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