Surface pollen distribution patterns in Beibu Gulf and corresponding sediment dynamics environment

The Beibu Gulf is a semi-enclosed gulf in the northwest of the South China Sea.We palynologically analyzed 306 surface sediment samples from the eastern Beibu Gulf to improve bioclimatic interpretation of fossil pollen records there.Surface pollen assemblages could be classified into five pollen regions based on the distributions of total,arboreal,herbaceous and fern pollen concentrations.Four high-concentration and three low-concentration subregions could be distinguished within these regions.The distribution patterns of surface pollen assemblages were consistent with those of grain sizes of surface sediments.Sediments from regions with high pollen concentrations were very fine and fine silts (>7.0,<0.008 mm),whereas those with low pollen concentrations were fine sand (<3.5,>0.088 mm).Sedimentary heterogeneity of surface pollen assemblages was closely related to pollen source,transportation and sedimentation controlled by ocean currents,tides and waves,and oceanic bottom topography.Fern spores exhibited higher percentages along the east margins of the region,while arboreal types like Pinus increased in concentration towards the center.Herbaceous pollen appeared in high percentages around seacoasts near their source areas.Dacrydium and mangrove pollen were distributed near their source regions at low percentages.We discuss the sediment dynamic environments in the eastern Beibu Gulf based on surface pollen distributions.The estuary region is an important access to the sea basin and a depositional site for terrestrial pollen grains.Coastal regions can accumulate pollen due to the back-and-forth movements of tides there.Although ocean currents on a gulf scale tend to spread pollen grains,the interaction of multiple currents could lead to pollen accumulation and deposition.Low surface pollen concentrations in the northeast shallow-water regions of the eastern Beibu Gulf could be attributed to repeated washing and sediment floatation caused by severe wave activities during the summer.Strong tides in Qiongzhou Strait frequently wash the seabed and disadvantage pollen deposition,leading to low surface pollen concentrations there.     

半群的Cwrpp根和半Cwrpp半群

引进Cwrpp根同余(集)、半Cwrpp半群的概念.研究了Cwrpp根同余(集)的性质.指出左Cwrpp(右Crpp)和完备rpp半群的Cwrpp根是强的,并给出它们的Cwrpp根的性质.证明了一个半群S是半Cwrpp的充分必要条件是S同构于一些Cwrpp半群的0-子直积.     

基于模糊神经网络的路桥工程建设项目应急能力评价

路桥工程建设项目发展迅速,然而其具有施工现场多、工序繁多、施工技术复杂等特点,容易造成大面积伤亡,因此对路桥工程建设项目进行应急能力评价尤为重要。为了对尚缺体系性的路桥工程建设项目应急能力领域进行评价,建立了路桥工程建设项目应急能力评价指标体系,提出了一种基于模糊神经网络的应急能力评价方法,建立了应急能力评价模型,克服了模糊综合评价法计算复杂、权重确定主观性强且效率低等缺点。并对某区域内5家路桥工程建设公司进行调研,按照模型方法进行评价,其评价结果与模糊综合评价法评价结果对比,实际结果显示,该模型方法具有精度高、操作简单等优点。     

非安全GSM网络监听平台的设计与DSP实现

。根据GSM网络的架构以及空中接口信号的特点,参考当前的科研成果设计了一种利用空中接口直接静默监听的方案,该平台能实现语音以及短消息的监听。本文分析了该方案的实现原理、硬件平台模块组成、接口设计、以及基带算法流程。最后通过DSP硬件平台仿真该算法流程,并根据算法解析的部分消息验证了该方案的可行性。     

驱动电压频率对荫罩式等离子显示屏的影响

研究了荫罩式等离子显示屏(SM-PDP)的驱动电压频率从100 kHz到250 kHz变化情况下,显示单元放电特性的变化.结果表明:随着驱动电压频率的提高,在相同的时间内放电次数增加,使产生的真空紫外辐射能量增加,可以提高显示的亮度,获得更高的对比度和灰度等级,同时壁电荷的积累减小,使单次放电反应变弱、放电效率降低,因而过高的驱动频率,也不能起到改善图像质量的作用;同时电极上的电流峰值减小,而其随时间的平均值增大,在设计驱动电路时,必须考虑其影响.因此在设计SM-PDP时合理的选择驱动电压的频率,可以使PDP的性能有很大的提高.     

Fault-tolerant rate-monotonic compact-factor-driven scheduling in hard-real-time systems

Considering the disadvantage of first-fit strategy in fault-tolerant rate-monotonic first-fit (FTRMFF) algorithm, we analyze the slack time of processors and the schedulability of periodic tasks in rate-monotonic (RM) algorithm. Then, the RM-based idleness factor and compact factor are presented to quantify the compact degree of tasks assigned to the same processor. In this paper, the novel fault-tolerant rate-monotonic compact-factor-driven (FTRMCFD) algorithm, which follows the principle of compact factor maximal when allocating the processors for tasks, is proposed. FTRMCFD algorithm makes every processor contain more tasks and get higher utilization to increase the schedulability performance of distributed systems. The simulation experiments reveal that FTRMCFD can reduce the number of required processors by up to 11.5% (with an average of 5.3%).     

三结砷化镓叠层太阳电池的光学匹配设计与分析

电流匹配是两端式多结叠层太阳电池设计中的关键和难点;同时,合理的吸收光谱分布将有利于电流匹配的获得。文章采用TFC光学薄膜仿真软件,模拟与分析了三结砷化镓太阳电池的多层减反射膜、顶电池窗口层和顶电池等功能层的吸收谱、反射谱和透射谱,以及对太阳电池吸收光谱的影响,结合太阳电池性能分析,得出了几何结构优化设计,可确保较好的电流匹配。     

独立学院“职业生涯规划与就业指导”课程的构建

文章从"职业生涯规划与就业指导"课程设置的意义、教学目标、课程体系的定位、课程体系建设原则、教学的方法、教学评价与教学管理等方面阐述了"职业生涯规划与就业指导"课程的构建。     

发电厂生产管理智能信息系统

在智能管理的理论、方法的基础上,提出了发电厂生产管理智能信息系统的实施方案．介绍了系统的设计目标、功能体系、系统网络结构与设备,以及系统软件的配置．该系统具有集成化、智能化、网络化的特点,可应用在电力企业生产管理智能信息系统．     

Radiolarian transfer function for paleo-primary productivity in the South China Sea

Basic data of radiolarian group and primary productivity were from 46 investigation stations of the South China Sea. The factor analysis of principal component and the least squares estimation in both linear regression and nonlinear estimation were applied to establishing the radiolarian transfer function for paleo-primary productivity in this sea area. The results show that the transfer function of nonlinear regression analysis for the radiolarian assemblage and primary productivity has much better parameters. Factors analysis has accumulating variance of 83.6% and communalities of more than 0.940347. Nonlinear regression analysis gives multiple correlation coefficient as 0.84888 and explained variance as 72.059%. The equation of transfer function is with an average estimated error of about 53.778 mg · C/m² · d, which is 14.69% in average observed values. Calculation accuracy is 85.31% for the system of transfer function.