TOGA-COARE IOP部分观测资料初步分析     

吴德星  孙即霖  王凡  傅子琅  陈荣裕  毛庆文  苗伟锋 《中国海洋大学学报(自然科学版)》1993,(Z2)

初步分析中国科学院南海海洋研究所《实验3号》科学考察船在TOGA—COARE IOP连续三个航次中部分CTD和ADCP原始观测资料指出:90-210m间大于35的盐度极值除存在准日周期变化外,在量值上还存在约73d的周期变化。但受资料长度的限制,目前尚无法确定上述周期是否属于稳定周期。在上述深度范围内亦存在较低盐度和温度水体侵入现象,其强度存在10—15d的周期变化。等温线和等密度线常出现振幅达10m以上,周期约3d的振荡,而且有时表现出次中尺度涡(submesoscale eddy)及涡旋链特征。比较风、SST、混合层深度间的关系时发现,风强度和大风维持时间对SST和混合层深度的影响很大,如西风暴发过程可使平均SST降低0.5℃左右,使平均混合层深度加深8m以上。分析西风暴发过程及西风暴发后洋流铅垂变化和洋流随时间变化发现,西风暴发过程导致79m以浅深度上的东向射流,且19m深处流动随时间顺时针改向,79m深处流动随时间逆时针方向改向。  相似文献   

网箱养殖大黄鱼体重与体长、体长与咽喉径之间的关系     

江琴  林武  陈坦  邓秀芳 《台湾海峡》2001,20(Z1):196-198

通过对大黄鱼体重、体长、咽喉径的准确测量，并将测量的原始数据经计算机统计回归分析.结果表明，大黄鱼体重与体长之间存在着幂函数关系；同时，当大黄鱼体重在5～100g范围内时，体长与咽喉径之间存在着线性函数关系.  相似文献   

铁磁链方程的二阶线性化隐式差分格式     

谢树森  张琎  薛恒 《中国海洋大学学报(自然科学版)》2004,34(6):1095-1097,1040

给出了解铁磁链方程的1个二阶线性化隐式差分格式；证明了差分解按离散L^2范数的最优阶先验误差估计及稳定性；给出数值算例。  相似文献   

Geographical Variations in Prosome Length and Body Weight of Neocalanus Copepods in the North Pacific     

Toru Kobari  Kazuaki Tadokoro  Akihiro Shiomoto  Shinji Hashimoto 《Journal of Oceanography》2003,59(1):3-10

Geographical variations in prosome length and body weight of Neocalanus copepods (N. cristatus, N. plumchrus and N. flemingeri) were investigated on samples from North-South and East-West transects in the North Pacific during spring to early summer in 1998 and 1999. Southward and eastward increasing patterns were pronounced for water temperature, although no significant pattern was observed for chlorophyll a concentrations. All Neocalanus species showed large geographical variations in prosome length and body weight, being smaller in the southern and eastern waters. Comparing the relationship between prosome length and body weight, large deviations (lower body weight at a given prosome length) were evident for the eastern specimens of N. cristatus and N. plumchrus. In stepwise regression analysis, the geographical variations of prosome length and body weight revealed a significantly negative correlation with temperature variations. These results suggest that temperature is a more important environmental factor than chlorophyll a concentration in its effect on geographical variations in prosome length and body weight of Neocalanus copepods in the North Pacific. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

城市平面坐标系建立方法的探讨     

张佃友  覃辉  夏元平 《海洋测绘》2007,27(4):17-19

随着经济的发展,城市扩建便成为必然的趋势,为解决原有坐标系存在的不足,如何选择城市坐标系便成了新的问题。在详细分析边长的高程归化以及边长的高斯投影改化的基础上,从变更中央子午线和投影面入手,提出了三种建立城市坐标系的技术方案,对测量工作者有一定的参考价值。  相似文献   

线性工程控制测量中投影变形处理方法研究     

王伯涛 《测绘与空间地理信息》2017,(6):196-198

对线性工程投影变形的特点以及解决方法进行了分析,并结合工程实例,通过对确定抵偿投影带和投影面的研究,获取了一种较为简便的控制长度变形的方法。在测区内采用一定限制的带宽和与设计高程相适应的投影面大地高,建立工程独立坐标系,即能有效地实现对两种长度变形的抵偿。实践证明,采用该方法能有效地解决线性工程控制测量长度投影变形问题。  相似文献   

村庄地籍调查中抵偿高程面的选择方法     

宋臣  张立宝 《测绘与空间地理信息》2017,40(9)

为克服投影变形对村庄地籍调查精度的影响,在不采用改变高斯投影带中央经线建立独立坐标系的情况下,本文通过采用抵偿高程面、抵消投影变形、保证地籍调查精度的原理方法,针对村庄地籍调查区域广、数据量大的特点,采用直接坐标改正的方法,不需要对控制测量成果进行重新解算,可以有效、快速地实现成果纠正,在村庄地籍调查实践中应用取得了较好的效果。  相似文献   

Complex resource supply chains display higher resilience to simulated climate shocks     

《Global Environmental Change》2017

Global resource supply chains deliver products such as fish, rice and minerals from producers to consumers around the world, linking disparate regions and economies. These supply chains are increasingly exposed to the impacts of a changing climate, yet receive little attention relative to the study of the production phase. Too often, business learns from experience if and how their supply chains can withstand and recover from climate shocks with little insight on proactively developing climate resilient supply chains. We use a network-based simulation approach to estimate the resilience of supply chains, particularly to disruption experienced during climate-related extreme events. We consider supply chain examples from three Australian resource industries – fisheries, agriculture and mining – that have experienced climate shocks in recent years. We derive four supply chain indices – evenness, resilience, continuity of supply and climate resilience – to estimate the performance of simple and complex supply chains in each industry. As with ecological systems, we show that complex supply chains with a large number of nodes and links are more resilient to disruption. Critically, all chains, regardless of their complexity, will have diminished resilience as climate disruptions become more frequent. This highlights the importance of considering the broader economic benefits of diversified chains, leading to risk reduction and improved design post-disruption. It also reinforces the importance of a systems approach to risk management in supply chains, particularly in considering adaptation options for addressing direct and indirect impacts on the chain as well as the global challenge of reducing greenhouse gas emissions.  相似文献   

混杂随机微分方程理论概述     

毛学荣 《南京气象学院学报》2017,9(3):246-261

本文对混杂随机时滞微分方程的当前发展及最新的研究成果进行了概述.主要回顾了混杂随机微分方程解的存在唯一性定理、稳定性、鲁棒有界性以及离散时间反馈镇定性等部分对混杂随机微分方程的研究起到关键推动作用的成果.  相似文献   

SURFACE-LAYER SCALING FOR THE CONVECTION-INDUCED STRESS REGIME     

A. A. GRACHEV  C. W. FAIRALL  S. S. ZILITINKEVICH 《Boundary-Layer Meteorology》1997,83(3):423-439

The Prandtl, Obukhov, and Monin andObukhov similarity theories are widely used todescribe the structure of turbulence in theatmospheric surface layer. Currently it isunderstood that in strong convection with no or veryweak mean wind the traditional theory breaks down.In particular, the traditional theory implies asingle-valued correspondence between localturbulence statistics and local properties ofthe flow. In very strong convection, this is nottrue because of large-scale ( 10 3 m) coherentstructures, embracing the entire convective boundarylayer (CBL). These structures produce random guststhat crucially affect surface-layer turbulence andmake it dependent on global properties of theflow, such as the CBL depth. In the present paperthe limits of validity of the traditional surface-layer similarity theory are determined and a revisedtheory of fair weather convection in the surface layeris developed by considering the effect of gustiness. It is shownthat the theoretical predictions are consistent withfield data from the TOGA COARE and SCOPEexperiments.  相似文献