奇异摄动对流扩散问题的区域分解算法

将奇异摄动对流扩散问题的区域分解算法推广到二维非定常的情形,并将Shishkin混合有限差分格式与区域分解方法结合, 得到了此类方程更高精度的并行算法.     

相容连续Domain的特征与浓度

引入相容连续Domain的权与稠密子集的概念,在此基础上定义相容连续Domain的特征与浓度.给出局部基的刻画,并讨论相容连续Domain的特征、浓度与相容连续Domain带上Scott拓扑或Lawson拓扑时拓扑空间的特征与浓度之间的关系.证明相容连续Domain的特征、浓度分别带上Scott拓扑时拓扑空间的特征、浓度相等,它们分别小于相容连续Domain带上Lawson拓扑时拓扑空间的特征与浓度.     

南大西洋被动陆缘沉积物厚度特征与分段对比

基于美国国家海洋和大气管理局(NOAA)发布的最新全球沉积物厚度数据, 综合利用被动陆缘盆地、洋底高原和转换断层等地质信息, 识别南大西洋七大沉积中心。南大西洋沉积物厚度整体上呈西厚东薄、北厚南薄的趋势, 按陆缘及盆地特征, 将大西洋两岸盆地从北到南划分为4段: 赤道段、中段、南段和福克兰段,其中被动陆缘盆地主要分布在前3段。赤道段盆地主要受转换断层控制, 发育三叠系蒸发岩; 中段盆地发育阿普第阶盐沉积, 是油气勘探的重点区域; 南段受火山活动的影响, 以发育向海倾斜反射体为主要特征。     

一种新型锚泊机器人研究

近年来,为了提高船舶的安全性和稳定性,锚泊机器人成为了海洋领域的研究热点。鉴于大西洋蛏的诸多优良性能,将以其为仿生对象来构建集掘进、锚定和自主脱附功能于一体的锚泊机器人本体。首先,阐述了锚泊机器人的国内外相关研究现状;其次,对仿大西洋蛏的锚泊机器人的机械设计进行原理性说明;最后,将重点介绍锚泊机器人的控制系统。实验结果表明,该控制系统能够使锚泊机器人完成掘进、锚定及自主脱附,并形成较大的锚定比。     

OTDR原理及其应用

介绍了OTDR的测试原理和基于OTDR的分布式光纤传感器的传感原理,总结了它们在各个领域的应用情况,并指出了未来的发展趋势。     

时域反射仪及其在节水农业研究中的应用

文中简要介绍了时域反射仪（ＴＤＲ）及其测定土壤水分的原理、特点和使用技术。根据在室内模拟滴灌土壤水分移动规律和田间微孔地膜渗水性能研究中应用ＴＤＲ测定土壤水分的两个试验,探讨了ＴＤＲ在节水农业研究中应用的优势。     

青藏高原对北大西洋深水形成影响机制的季节差异

利用耦合地球系统模式(CESM1.0),通过对比有青藏高原的控制试验和无青藏高原的敏感性试验,定性地分析青藏高原对不同季节北大西洋深水(NADW)形成的影响机制.研究结果表明,青藏高原对NADW形成的影响机制因季节而异.移除青藏高原后,NADW形成将会减弱,冷季(北半球10月—次年3月)NADW形成的显著减弱是由海洋表...     

拟Z-连续Domain的基

基于一般子集系统Z,引入了拟Z-连续Domain基的概念,讨论了拟Z-连续Domain基的一些映射性质,将关于拟连续偏序集的一些性质推广到了拟Z-连续Domain.     

Comparison of zooplankton community structure between impacted and non-impacted areas of Paranaguá Bay Estuarine Complex,south Brazil

We analysed the seasonal distribution of the zooplankton community in an anthropogenically impacted area (Paranaguá Bay) and a non-impacted area (Laranjeiras Bay) of the Paranaguá Bay Estuarine Complex. Large phytoplankton (> 50 μm) and zooplankton were collected every two months, between August 2003 and June 2004. The phytoplankton community was numerically dominated by diatoms (78%) and dinoflagellates (19%). Zooplankton abundance varied between 670 and 100,716 individuals m^–3, with a dominance of copepods, mainly the calanoids Acartia lilljeborgii, Acartia tonsa and Pseudodiaptomus acutus. A clear seasonal pattern was observed: copepods were significantly more abundant during the rainy than in the dry season. Significant differences in abundance between the two bays were detected only for cirripede larvae, which were more abundant in Paranaguá Bay. This lack of difference between the two areas was probably a consequence of the water circulation along the estuary, which may have diluted and dispersed the pollutants from Paranaguá Bay to other areas of the estuary.     

Foraging patterns and artificial fragrance choices of male orchid bees in the Brazilian Atlantic Rainforest

ABSTRACT

With the aim of increasing our knowledge concerning fragrance choices by male euglossine bees (Apidae, Euglossini), we investigated: (i) possible foraging patterns and choices of artificial fragrances explored by the most frequent species attracted to scent baits during the same season across consecutive years, sampled invariably in a same study area; (ii) the foraging patterns of populations of orchid bees surveyed in two similar forest habitats (Atlantic rainforest remnants) located 24 km apart, on Superagui Island (SI) and on a private reserve (RNSM), in southern Brazil. Although in both areas males attracted to scent baits were collected with insect nets and odour traps during the warm-wet season, the number of samplings were different in both study sites, totalling 15 samplings on RNSM and five on RNSM. In both areas four euglossine species were the most abundant: Euglossa annectans, E. stellfeldi, E. iopoecila and E. roderici. Overall, we can draw three main conclusions. Firstly, there were conspicuous patterns in regard to the set of fragrances visited by the four most abundant euglossine species over the three consecutive years of surveys on SI, with some shifts in fragrance choices found only for E. annectans and E. stellfeldi. Second, the most attractive fragrances used distinctively by each species were very similar in both study areas, indicating a local intraspecific similarity in the use of some main fragrances. Third, E. annectans showed a clear tendency to occupy a broader niche, which probably resulted in the highest percentages of niche overlap.