港口靠船桩工作性状计算的双参数法   总被引：8，自引：0，他引：8  

谢耀峰 《海洋工程》2002,20(2):38-42,48

港口靠船桩是承受重复性荷载或多循环荷载的一种横向承载桩。双参数法能较好地描述靠船桩 (单桩、群桩 )的桩土工作性状。用双参数法进行计算时 ,所给的地面条件必须由重复荷载或多循环荷载作用下实测出来。根据现场试桩资料 ,标定桩土参数 ,即k =mx1/n的指数l/n、桩土相对柔度系数α、桩土综合刚度EI等值 ,可以用来设计试桩附近局部地区同类条件下的其它长桩。对于没有进行试桩的某些工程 ,可以联合运用双参数法和p -y曲线法进行桩的分析  相似文献   

Composition and distribution of copepods, a major prey of capelin in the central Barents Sea, in moderate and warm years     

Orlova  Emma L.; Boitsov  Vladimir D.; Nesterova  Valentina N.; Ushakov  Nikolai G. 《ICES Journal of Marine Science》2002,59(5):1053-1061

  相似文献   

青岛市大气污染时间序列分析预报方法研究   总被引：5，自引：0，他引：5  

黄磊  王赐震  王建华  于鹏 《中国海洋大学学报(自然科学版)》2001,31(1):14-20

根据青岛市大气污染监测资料 ,采用时间序列分析方法 ,建立多种预报模型 ,有原序列周期外延法、均生函数周期外延法、均生函数逐步回归法以及自回归预报法等 ,最后提出一种综合预报模型。连续预报试验表明 ,综合预报模型优于任何个别预报模型 ,有较好的预报能力。利用马尔可夫概型对污染状态 (轻、中、重 )进行了分级预报试验 ,也获得良好的效果。  相似文献   

LabVIEW设计中压力传感器的RBF神经网络温度补偿   总被引：5，自引：0，他引：5  

毕海军  傅圣雪  冯遵成 《中国海洋大学学报(自然科学版)》2004,34(6):1041-1044

在石油平台注水压力监测系统设计中 ,采用LabVIEW虚拟仪器平台 ,嵌入逼近能力强和收敛速度快的RBF神经网络 ,以人工环境实验数据为样本进行训练 ,实现了压力传感器的智能网络温度补偿。结果显示 ,此方法能够在压力、温度变化较大的恶劣环境下 ,获得很高的补偿精度。  相似文献   

东亚冬夏季风对热带印度洋秋季海温异常的响应   总被引：5，自引：0，他引：5  

李东辉  谭言科  张瑰  叶志敏 《热带海洋学报》2006,25(4):6-13

利用多年的Reynolds月平均海表温度资料和NCEP/NCAR全球大气再分析资料,分析了热带印度洋秋季海表温度距平(SSTA)与后期东亚冬夏季风强度变化的关系。结果表明,热带印度洋秋季SSTA的主要模态是全区一致(USB)型和偶极子(IOD)型,USB型模态主要代表热带印度洋秋季SSTA的长期变化趋势,而IOD型模态主要反映热带印度洋秋季SSTA的年际变化。热带印度洋秋季海温气候变率中既存在着明显的ENSO信号,也有独立于ENSO的变率特征,独立于ENSO的热带印度洋秋季SSTA变化的主要模态仍是USB型和IOD型。前期秋季USB模态与东亚冬季风及东亚副热带夏季风之间为负相关关系;与前期正(负)IOD模态相对应,南海夏季风强度偏弱(强),而东亚副热带夏季风强度偏强(弱)。USB型和IOD型模态对后期东亚冬、夏季风强度变化的影响是独立于ENSO的,但ENSO起到了调节二者相关显著程度的作用。  相似文献   

热带印度洋偶极子发生和演变机制的数值研究   总被引：5，自引：0，他引：5  

李东辉  张铭  张瑰  谭言科 《海洋科学进展》2005,23(2):135-143

对中国科学院大气物理研究所(IAP)大气科学和地球流体力学数值模拟国家重点实验室(LASG)发展的第三代海洋模式(L30T63 OGCM)进行了改进。分析了该模式1959年1月—1998年12月的40a积分结果，以此研究热带印度洋偶极子发生、发展和消亡的物理机制。对数值模拟结果的分析表明，赤道印度洋表面异常东风引起的异常环流结构是偶极子发生、发展的主要动力学原因，其表面异常东风转换为异常西风所引起的异常环流结构调整是偶极子消亡的主要动力学原因；海气界面热通量异常的交换对热带印度洋海表温度距平偶极子模态的形成和演变起着重要的作用；垂直输送作用是热带印度洋次表层海温偶极子模态发生和演变的主要物理机制。  相似文献   

Aliasing due to sampling of the Adriatic temperature, salinity and density in space     

Zoran Pasari&#x;  Mirko Orli&#x;  Craig M. Lee 《Estuarine, Coastal and Shelf Science》2006,69(3-4):636

High-resolution underway temperature and conductivity measurements collected by R/V Knorr during winter and spring 2003 are used to characterize errors associated with spatial aliasing in the northern and central Adriatic Sea. During winter, 99th percentile temperature, salinity and density errors were 0.62 °C, 0.25 and 0.12 kg/m³ (0.25 °C, 0.10 and 0.05 kg/m³) for sampling at 10 km (5 km) horizontal resolution, respectively. The corresponding values in spring were 1.31 °C, 0.50 and 0.40 kg/m³ (0.93 °C, 0.25 and 0.22 kg/m³) for the 10 km (5 km) sample spacing, respectively. The largest errors were associated with energetic regions over the shallow, western Adriatic, in front of the Po River mouth and off the tip of the Istrian peninsula. The deeper eastern basin exhibited smaller errors. The variability of errors in time and space reflected the variability of small-scale density features, characterized by wavelengths as small as 2 km in winter and 1 km in spring and being more pronounced in the western and northern parts of the Adriatic. As these results indicate that errors associated with undersampling can be considerable, they should be taken into account while planning future CTD measurements in the region.  相似文献   

黄海、渤海底层温度数值预报方法的研究     

王宗山  徐伯昌  龚滨  邹娥梅  李繁华 《海洋科学进展》1996,(3)

根据文献［ｌ］建立的底层温度（ＴＨ）与其水柱垂向平均温度（）的经验关系，结合流体动力学方程和（垂向平均）热传导方程，发展了以水气温差和风速为已知量的底层温度二维数值预报模式。该模式避开了海面热量和动量输入在垂直水柱中分配的复杂物理过程而直接报出底层水温场，具有较好的实用性；此外，从试报结果看，效果令人满意。  相似文献   

Oxygen Uptake During Repeated Exposure to Temperature Change: Physiological Divergence in Panamanian Cognate Pairs and Latitudinally Distant Populations of Decapod Crustacea     

J. D. Ferraris  J. L. Norenburg 《Marine Ecology》1997,18(2):127-146

Abstract. The emergence of the Isthmus of Panama subdivided the amphi-American biota. In the present study, Pacific and Atlantic populations of four cognate pairs of crabs were used to discern whether exposure to different thermal regimes in habitats, in the putative absence of gene flow, has resulted in physiological divergence. Populations that potentially form a common genetic pool were also used; these were populations of the Atlantic Panama cognate that occur in Belize and Florida. Decreases in water temperature occur periodically in Pacific Panama and Florida, but not in Atlantic Panama or Belize. In this study, physiological divergence in oxygen uptake was assessed in response to repeated exposure to either control and decreased temperature or control and increased temperature. Results indicate that, in only some of the genera tested, exposure to decreases in habitat temperature has resulted in divergence. Partial support is found for the corollary that adaptation to an environment with periods of decreased temperature results in reduced compensation during exposure to elevated temperature.  相似文献   

Subsurface Water Masses in the Central North Pacific Transition Region: The Repeat Section along the 18° Meridian     

Toshio Suga  Kazunori Motoki  Kimio Hanawa 《Journal of Oceanography》2003,59(4):435-444

A repeat hydrographic section has been maintained over two decades along the 180° meridian across the subarctic-subtropical transition region. The section is naturally divided into at least three distinct zones. In the Subarctic Zone north of 46°N, the permanent halocline dominates the density stratification, supporting a subsurface temperature minimum (STM). The Subarctic Frontal Zone (SFZ) between 42°–46°N is the region where the subarctic halocline outcrops. To the south is the Subtropical Zone, where the permanent thermocline dominates the density stratification, containing a pycnostad of North Pacific Central Mode Water (CMW). The STM water colder than 4°C in the Subarctic Zone is originated in the winter mixed layer of the Bering Sea. The temporal variation of its core temperature lags 12–16 months behind the variations of both the winter sea surface temperature (SST) and the summer STM temperature in the Bering Sea, suggesting that the thermal anomalies imposed on the STM water by wintertime air-sea interaction in the Bering Sea spread over the western subarctic gyre, reaching the 180° meridian within a year or so. The CMW in this section originates in the winter mixed layer near the northern edge of the Subtropical Zone between 160°E and 180°. The CMW properties changed abruptly from 1988 to 1989; its temperature and salinity increased and its potential density decreased. It is argued that these changes were caused by the climate regime shift in 1988/1989 characterized by weakening of the Aleutian Low and the westerlies and increase in the SST in the subarctic-subtropical transition region. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献