鱼梁航运枢纽鱼道及鱼类增殖保护站设计浅述

航运枢纽的建设对鱼类生态环境及鱼类资源影响较大,为减缓工程对鱼类的不利影响,文章通过综合分析,提出采取修建过鱼设施和建立增殖保护站、开展人工增殖放流为主要鱼类保护措施,并结合鱼梁枢纽工程,对鱼道结构及布置、增殖保护站布置及生产方式等设计进行介绍。     

热再生技术在沥青路面病害修补中的应用

热再生养护是一种非常适合我国公路养护需要的新技术,能快速修补沥青路面病害,并延长公路的使用寿命。     

Observations on colony formation by the cosmopolitan phytoplankton genus Phaeocystis

Few marine phytoplankton have heteromorphic life cycles and also often dominate the ecosystems in which they occur. The class Prymnesiophyceae contains a notable exception: the genus Phaeocystis includes three species that form gelatinous colonies but also occur within their ranges as solitary cells. Phaeocystis antarctica and P. pouchetii are exclusively high latitude taxa, and are notable for regionally tremendous blooms of the colony stage. P. globosa occurs circumglobally, yet its colony blooms primarily are confined to colder waters within its range. Three additional species are warm water forms that have been reported only as solitary cells or loose aggregations that bear little resemblance to the organized colonies of the other taxa. Interpretation of existing data indicates that resource availability (light, temperature and nutrients) by itself is not sufficient to explain this distinction between cold-water colony-forming taxa and warm water solitary cell taxa, nor why colony development in P. globosa is essentially a spatially restricted phenomenon within a much broader geographic range. Colony development by P. globosa in situ has been observed at temperatures ≥20 °C, but only rarely and generally under conditions of seasonally or anthropogenically elevated nutrient supply. Data presented here demonstrate colony development at 20–22 °C in natural plankton communities from oligotrophic waters that were pre-screened through 63 μm mesh (i.e. lacking mesozooplankton and large microzooplankton), but not in unscreened communities containing microzooplankton and >63 μm zooplankton. Reduction of colony proliferation at higher temperatures by mesozooplankton grazing remains as an intriguing possibility that is consistent with available evidence to help explain differences in latitudinal extent of in situ colony development. These data are interpreted within a theoretical framework regarding the potential advantages and disadvantages of the two life cycle stages.     

汽车正面碰撞事故车速预测模型仿真研究

为了能有效准确地根据事故现场情况预测出碰撞前车辆的运行车速情况,文章利用反推算法,遵循相关物理定律,构建正面碰撞事故中车辆相关参数及道路条件与车速的函数关系,并基于Visual Basic平台搭建车速预测模型并进行实测验证。结果表明,所构建模型的误差率较低,所构建模型、系统是正确高效的,可用于正面碰撞事故的车速预测研究工作。     

Life cycle strategies of free-living copepods in fresh waters

Freshwater copepods live in habitats characterized by a high degree of instability. To survive occasional deterioration of their environment copepods have evolved adaptive mechanisms like dormancy or migration in order to avoid lethal conditions and to synchronize growth and reproduction with favourable abiotic and biotic conditions. Typical life cycles of harpacticoid, calanoid and cyclopoid copepods are presented to show strategies that have evolved to survive threatening environmental conditions.     

Life cycle of Epischura baicalensis Sars (Copepoda, Calanoida) in Lake Baikal

Epischura baicalensis Sars is a dominant pelagic species of Lake Baikal zooplankton. This is endemic to Lake Baikal and inhabits the entire water column. It produces two generations per year: the winter–spring and the summer. These copepods develop under different ecological conditions and vary in the duration of life stages, reproduction time, maturation of sex products and adult males and females lifespan. The total life period of the animals from each generation is one year. One female can produce 10 egg sacks every 10–20 days during its life time. The ratio of males and females is 1:1. One of the most essential features of the ecology of E. baicalensis is the alteration of its mass inhabited areas during a year, as well as in day time. This is due to the need for various conditions for gonad maturation, reproduction, nourishing and protection from being consumed by planktivors.     

和谐号动车组制动系统故障再现及分析

制动系统的可靠性是和谐号动车组正常运用的重要保障,为此制动系统必须具备良好的故障诊断能力和故障存储功能,以便于进行故障快速定位从而方便维修.对于复杂故障、疑难故障和系统类的故障等,则需要针对现车进行故障再现与分析,或结合试验台等可靠性试验手段和方法进行可靠性试验验证,排查故障的根本原因从而消除故障隐患.     

Distribution, reproduction and development of Calanus species in the Northeast water in relation to environmental conditions

The vertical and horizontal distribution of mesozooplankton biomass and its composition, together with the reproduction and development of the three dominant herbivorous copepods Calanus finmarchicus, C. glacialis and C. hyperboreus, were studied in the Northeast Water between the end of May and end of July, 1993. Biomass varied between 0.15 and 10.6 g m⁻² and was lower on the shallow banks. Highest biomass was found on the shelf slope and in the entrances to Belgica and Westwind Troughs. There was no seasonal trend during the study period. Among the zooplankton taxa, copepods were dominant, with 84% biomass of all other taxa, followed by chaetognaths with 14%. The large Calanus species made up 91% of copepod biomass. The most abundant species, C. glacialis, inhabited areas of low current speeds on Belgica and Ob Bank, C. hyperboreus dominated shelf slope and trough stations, while C. finmarchicus was most abundant in the Return Atlantic Current along the shelf slope and also eastern Belgica Trough. C. glacialis was the only Calanus species spawning during this period, but young copepodites of the other species were also abundant. Egg production of C. glacialis was at a maximum by our arrival and continued to at least mid August. According to the results from starvation experiments, its egg production was fuelled by food uptake, but was decoupled from phytoplankton chlorophyll until July, indicating ice-algae and microzooplankton as an alternative food source. Only when the polynya approached its maximum extent was a close relationship to phytoplankton established. Due to both spatial and temporal heterogeneity of the occurrence of young copepodite stages it was impossible to follow the growth of cohorts of developmental stages. Herbivorous carbon requirements estimated from egg production rates were mostly less than one third of the phytoplankton stock. From egg production and the distribution of young stages, the outer Westwing Trough seems to be the centre of biological activities. This may be related to the formation of young ice in winter in this area, which was found to carry a large mass of under-ice algae. High biomass but low production in Belgica Trough indicate this as an advective and expatriated community of C. finmarchicus and C. hyperboreus, where grazing is negligible, at least during early summer.     

机器脚踏车数字行车纪录器数据分析与应用

数字行车纪录器来对机器脚踏车进行其主要的数据研究及探讨,纪录器能连续纪录及储存车辆行驶速率、加速度、经纬度坐标、距离及时间,并透过数据传输功能单元汇入档案,以档案进行数据输出及分析,来得知车辆行驶之行车路程与驾驶行为,进行不当驾车行为之统计以及异常状况的管理辅导的要求,判断驾驶员的驾驶行为是否不良,对其做事前防范管理措施,并运用行车纪录器所得到的数据来做事故重建的鉴定,更能协助提供检警作车祸的参考,对事故提出改善建议,配合＂3Ds MAX＂的应用更能表现其数据的分析结果,利用＂3Ds MAX＂动画制作软件来协助车祸现场重建,因动画仿真有其参考价值,运用其仿真性来还原事故发生的情况,使相关人员更容易了解车祸的过程与发生的原因,藉由行车纪录器的数据整合,让相关人员不需要再花费大量的时间在于车祸的重建探讨,让类似案件避免再发生。     

基于WLAN的数据还原模型

提出了在公共无线局域网WLAN（Wireless Local Area Network）环境下一种数据还原模型．通过对无线局域网的数据采集与分析,利用会话重聚算法快速分类数据中的多个会话与连接,提出一种单一会话对应多个连接的方法,合并每个会话中的不同连接的数据信息,并采用多线程并发处理技术最终实现一种快速的信息重放与还原模型．最后通过对该模型的处理时延和执行效率的分析,表明该模型能够对无线局域网的数据尽最大可能的快速还原与重放．