世界科技革命的机遇和自主创新的轨迹与以德为先振兴中华

在科学与技术创造的进程中,德与智是何等重要!习近平总书记最近指出:"全面建设小康社会正处在新的历史起点上,我国改革发展正处在关键阶段,希望广大青年科技工作者力争在科技创新、产业发展、技能突破等方面不断取得新进步;要恪守科学精神、脚踏实地、埋头苦干、坚忍不拔、不畏挫折、淡泊名利、不浮不躁.始终保持探索真知的坚定意志和创新创业的高昂激情:要勇做创新先锋,善于攻坚克难,努力形成一流的科研成果".本文给出作者感悟和对学界同仁的期盼.     

地名是把双刃剑，应谨慎更改

20世纪80年代以来,中国经历了一场历史上从未有过的深刻变革。这种变革不仅表现在政治、经济、文化领域,而且表现在地名领域。为了更好地招商引资,扩大知名度,各地纷纷更名就是集中表现之一。其中影响较大的有：安徽省1987年撤销徽州地区,设立地级黄山币;1998年湖北省蒲圻市更名赤壁市;     

行动者网络视角下批发市场新电商模式

在电商兴起和旧城更新的背景下,传统批发市场出现衰退趋势,亟需转型升级。本文在梳理广州市一德路海味干货市场转型历史的基础上,得出市场近年经历了由衰退到出现电商再到综合升级的初步判断,并构建了一德市场电商化的行动者网络模型探讨转型机制和效应。通过深入的现场调查,详尽分析人类行动者如商、客、政府和非人类行动者如海味干货商品、网络在电商化过程中的作用,得出具体的转型新模式。研究表明：①传统批发市场经过电商化转型,不会走向单一电商化或地理空间无用化的极端,而是出现综合多样的业态形式,如电商和实体、批发和零售4种类型的交叉组合;②在引发传统批发市场转型的多元行动者力量中,非人类主体如商品和网络发挥着巨大的作用,如商品的客观特性阻碍着地理空间的消除,而网络引发人们对空间重要性的重新权衡和促进对实物商品的升级改造。     

南海北部孤立波对近岸波动的响应

On the basis of the time series observations from a temperature chain and an acoustic Doppler current profiler on the continental shelf of the northern South China Sea, a sequence of internal solitary waves （ISWs） and background waves （BWs, including internal tides and near-inertial waves） on the continental shelf were captured simultaneously after the transit of Typhoon Neast in October 2011. These measurementsprovided a unique opportunity to explore the influence of BWs on the ISWs. The BWs appeared a conversion on the current strength and vertical mode structure during the observational period. The BWs were dominated by weak and mode-one waves before October 2 and then turned to strong and high-mode waves after that time. Meanwhile, the ISWs displayed different wave structures before and after October 2, which was closely related to BWs＇ changes. According to the current profiles of BWs, the high-mode wave structure with strong current could significantly strengthen the vertical shear of ISWs in the near-surface layer and promote the breaking of ISWs, and thus it may play an important role in affecting the background current condition.     

初始倾斜跃层所致内波的数值研究

The pycnocline in a closed domain is tilted by external wind forcing and tends to restore to a level posi- tion when the wind falls. An internal seiche oscillation exhibits if the forcing is weak, otherwise internal surge and internal solitary waves emerge, which serve as a link to cascade energy to small-scale processes. A two-dimensional non-hydrostatic code with a turbulence closure model is constructed to extend previous laboratory studies. The model could reproduce all the key phenomena observed in the corresponding labo- ratory experiments. The model results further serve as a comprehensive and reliable data set for an in-depth understanding of the related dynamical process. The comparative analyses indicate that nonlinear term favors the generation of internal surge and subsequent internal solitary waves, and the linear model predicts the general trend reasonably well. The vertical boundary can approximately reflect all the incoming waves, while the slope boundary serves as an area for small-scale internal wave breaking and energy dissipation. The temporal evolutions of domain integrated kinetic and potential energy are also analyzed, and the results indicate that about 20% of the initial available potential energy is lost during the first internal wave breaking process. Some numerical tactics such as grid topology and model initialization are also briefly discussed.     

深水SCR触地区管-土相互作用试验研究进展

与海床的相互作用是钢悬链线立管特有的性质,是传统立管发展中不曾遇到的问题,也是控制立管疲劳寿命的主要因素,特别是触地区出现的峰值弯曲应力和管土接触模型的不确定,成为SCR触地区研究的难点。由于立管与海床的作用机理非常复杂,因此管土相互作用模型的提出大多是建立在模型试验的基础上。通过对国内外深水SCR触地区管土相互作用试验研究案例的分析,简要介绍了SCR触地点的动态响应取决于一系列参数,如海床土刚度、加载状况、立管的提升速度、土的重塑时间和土吸力等,并设计了一套三维管-土相互作用的试验装置,能够为深水钢悬链线立管触地区管-土相互作用的试验研究提供参考。     

5400阶次勒让德函数的递推计算方法

超高阶球谐重力场模型由超高阶次勒让德函数构成。即使采用压缩因子递推计算超高阶(如大于3600阶)勒让德函数,在两极附近仍然会出现溢出(上溢或下溢)而导致计算失败。基于对递推公式的分析,利用改进的压缩因子修正递推算法,可以得到直到5400阶次高精度"压缩勒让德函数",且仍可用Horner技术求和。     

超高阶地球重力场模型的高程异常优化算法

通过分析比较标准前向列推、标准前向行推、跨阶次递推和Belikov列推4种缔合勒让德递推算法的精度、稳定性以及计算速度,提出了选取Belikov列推法来解算超高阶重力场模型高程异常;研究探讨了基于严密球谐级数展开、保留泰勒级数展开的零阶项和保留至泰勒级数展开一阶项计算模型高程异常的三种算法,并进行了实验计算分析。结果表明,保留至泰勒级数一阶项的模型高程异常既能保证计算速度也能达到足够的精度,可满足大区域高分辨率高程异常建模的需求。