PCI9052在PCI接口卡中的应用

结合具体的应用,介绍基于PCI9052接口卡开发过程中一些需要注意的问题。     

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Impact factors on distribution and characteristics of natural plant community in reclamation zones of Changjiang River estuary

To identify impact factors on the distribution and characters of natural plants community in reclamation area, with survey data from 67 plant quadrats in July 2009, soil properties data from 216 sampling points in April 2009, and TM (30 m) data in 2006, the composition and characteristics of natural plants community in different time of the Fengxian area in the Changjiang (Yangtze) River estuary were analyzed with two-way indicator species analysis (TWINSPAN), multivariate analysis of variance (MANOVA), detrended canonical correspondence analysis (DCCA) and canonical correspondence analysis (CCA). The results show that: 1) The plant communities in the reclaimed area are mainly mesophytes and helophytic-mesophytic transitional communities, showing a gradient distribution trend with the change in reclamation years. Species richness (MA), species diversity (H) and above-ground biomass also increase with the increase of reclamation years. Nevertheless, they appear to decline slightly in the middle and late reclamation period (> 30 years). 2) With the rise in land use levels, the changes in species richness and species diversity tend to increase at first and then decrease; species dominance (D), however, tends to decline; and above-ground biomass increases slightly. 3) The distribution of the plant community is mainly influenced by the following factors: land use levels (R = 0.55, p < 0.05), soil moisture (R = 0.53, p < 0.05), soil salinity (R = 0.43, p < 0.05) and reclamation time (R = 0.40, p < 0.05).     

Field experiments of multi-channel oceanographic fluorescence lidar for oil spill and chlorophyll-a detection

A Multi-channel Oceanographic Fluorescence Lidar (MOFL), with a UV excitation at 355 nm and multiple receiving channels at typical wavelengths of fluorescence from oil spills and chlorophyll-a (Chl-a), has been developed using the Laser-induced Fluorescence (LIF) technique. The sketch of the MOFL system equipped with a compact multi-channel photomultiplier tube (MPMT) is introduced in the paper. The methods of differentiating the oil fluorescence from the background water fluorescence and evaluating the Chl-a concentration are described. Two field experiments were carried out to investigate the field performance of the system, i.e., an experiment in coastal areas for oil pollution detection and an experiment over the Yellow Sea for Chl-a monitoring. In the coastal experiment, several oil samples and other fluorescence substances were used to analyze the fluorescence spectral characteristics for oil identification, and to estimate the thickness of oil films at the water surface. The experiment shows that both the spectral shape of fluorescence induced from surface water and the intensity ratio of two channels (I ₄₉₅/I ₄₀₅) are essential to determine oil-spill occurrence. In the airborne experiment, MOFL was applied to measure relative Chl-a concentrations in the upper layer of the ocean. A comparison of relative Chl-a concentration measurements by MOFL and the Moderate Resolution Imaging Spectroradiometer (MODIS) indicates that the two datasets are in good agreement. The results show that the MOFL system is capable of monitoring oil spills and Chl-a in the upper layer of ocean water.     

高重频激光测距数据处理方法

该文探讨了高重频激光测距工作中的数据处理问题。该数据处理采用了屏幕显示以及数学分析方法,以剔除卫星激光测距数据中的观测异常值,提取有效的数据点,并最终生成标准点数据。通过对奥地利GRAZ激光测距站高重频数据资料的处理表明,该数据处理方法是有效的。     

Sensory bases and the mode of feeding behavior of tongue sole <Emphasis Type="Italic">Cynoglossus semilaevis</Emphasis>

We conducted behavior experiments on the roles of vision, olfaction, and the lateral line in feeding in tongue sole Cynoglossus semilaevis Günter. Chemical cues from the prey alone could not elicit any searching or attacking behavior by the fish; only when moving foods were presented, the chemical nature of the foods affected feeding. In addition, we found that normal tongue sole did not accurately recognize moving artificial prey of different shapes. Neither chemosense nor vision plays an important role in prey detection. Reactions to moving objects and the response of the oropharyngeal cavity to different foods showed that the (eyeless) tongue sole use mainly the lateral line for prey detection and capture. Gustation in the oropharyngeal cavity is essential for the fish to swallow its prey.     

Electrochemical corrosion behavior of hot dip coating in artificial seawater

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四川盆地汛期旱涝预测研究

对近１０年来四川盆地汛期降水预测水平进行了定量评估,并与国家气候中心预测水平作了对比。在分析影响四川盆地汛期降水主要物理因素的基础上,提出了四川盆地汛期旱涝预测的基本思路和技术方法,并在实际业务预报中取得了较好的效果。     

Sensitivity of streamflow from a Himalayan catchment to plausible changes in land cover and climate

Global climate change will likely increase temperature and variation in precipitation in the Himalayas, modifying both supply of and demand for water. This study assesses combined impacts of land‐cover and climate changes on hydrological processes and a rainfall‐to‐streamflow buffer indicator of watershed function using the Soil Water Assessment Tool (SWAT) in Kejie watershed in the eastern Himalayas. The Hadley Centre Coupled Model Version 3 (HadCM3) was used for two Intergovernmental Panel on Climate Change (IPCC) emission scenarios (A2 and B2), for 2010–2099. Four land‐cover change scenarios increase forest, grassland, crops, or urban land use, respectively, reducing degraded land. The SWAT model predicted that downstream water resources will decrease in the short term but increase in the long term. Afforestation and expansion in cropland will probably increase actual evapotranspiration (ET) and reduce annual streamflow but will also, through increased infiltration, reduce the overland flow component of streamflow and increase groundwater release. An expansion in grassland will decrease actual ET, increase annual streamflow and groundwater release, while decreasing overland flow. Urbanization will result in increases in streamflow and overland flow and reductions in groundwater release and actual ET. Land‐cover change dominated over effects on streamflow of climate change in the short and middle terms. The predicted changes in buffer indicator for land‐use plus climate‐change scenarios reach up to 50% of the current (and future) range of inter‐annual variability. Copyright © 2010 John Wiley & Sons, Ltd.