棘皮动物再生研究进展   总被引：1，自引：0，他引：1  

樊廷俊  杜玉堂  丛日山  于苗苗 《中国海洋大学学报(自然科学版)》2007,37(4):563-568

棘皮动物具有极强的再生能力,在进化上和发育上与脊椎动物具有许多相似性,是在器官、组织、细胞和分子水平上研究后口动物再生过程与再生机理的理想模式动物。本文综合该领域的研究现状并结合作者的研究成果,对棘皮动物再生的研究进展进行综述。  相似文献   

复合加载条件下吸力式沉箱基础承载特性数值分析   总被引：2，自引：0，他引：2  

王志云  王栋  栾茂田  范庆来  武科 《海洋工程》2007,25(2):52-56,71

吸力式沉箱基础的承载特性是海洋工程结构设施建造与设计中的一个关键问题。这种新型的深水海洋基础型式,通常承受竖向上拔荷载与水平荷载的共同作用,其工作性能与设计理论远远不能满足工程实践的需要。本文采用有限元分析方法对吸力式沉箱基础的极限承载特性进行数值计算。以大型通用有限元分析软件ABAQUS为平台,通过二次开发,数值实现了Swipe试验加载方法和固定位移比分析方法,针对不同的沉箱长径比、土的强度折减系数,探讨了沉箱基础在垂直上拔荷载和水平荷载单调联合作用下的极限承载力,通过对不同荷载组合的数值计算构造了复合加载条件下沉箱基础破坏包络面。  相似文献   

Freshening of the Intermediate Waters in the Northern South China Sea over the PastSix Decades     

陈栩洋  王东晓  舒业强  成里京  范双双 《热带气象学报(英文版)》2024,30(1):42-50

The properties of salinity in the South China Sea (SCS), a significant marginal sea connecting the Pacific andIndian Oceans, are greatly influenced by the transport of fresh water flux between the two oceans. However, the long-termchanges in the intermediate water in the SCS have not been thoroughly studied due to limited data, particularly in relationto its thermodynamic variations. This study utilized reanalysis data products to identify a 60-year trend of freshening in theintermediate waters of the northern South China Sea (NSCS), accompanied by an expansion of low-salinity water. Thestudy also constructed salinity budget terms, including advection and entrainment processes, and conducted an analysis ofthe salinity budget to understand the impacts of external and internal dynamic processes on the freshening trend of theintermediate water in the NSCS. The analysis revealed that the freshening in the northwest Pacific Ocean and theintensification of intrusion through the Luzon Strait at intermediate levels are the primary drivers of the salinity changes inthe NSCS. Additionally, a weakened trend in the intensity of vertical entrainment also contributes to the freshening in theNSCS. This study offers new insights into the understanding of regional deep sea changes in response to variations in boththermodynamics and oceanic dynamic processes.  相似文献   

Ore-control structural features of Xiadian Ⅶ-branch orebody     

CUI Yun-Long  DONG xin  SUN Li  WANG Kun  ZHOU Chun-sheng  FAN Si-qi  DU Pei-jie 《吉林地质》2008,27(3)

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Seismic facies characteristics and cognition of coal seam eroded by igneous rocks     

XUN Feng-gang  REN Ri-chun  PEI Zhong  TIAN Ya-jing  LIU Hai-tao 《吉林地质》2008,27(4)

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The analysis and method of two-dimensional seismic observation system templates     

WANG Li-bin  REN Ri-chun  PEI Zhong  TIAN Wei 《吉林地质》2008,27(4)

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遥感影像数据库设计与实现     

李忠  邓喀中  王华斌  凌宇飞 《四川测绘》2008,31(4)

遥感影像数据库的设计与实现,主要实现多源遥感影像数据的管理.通过调用GDAL库,实现多源遥感影像数据的读取,对影像数据进行分块,建立影像金字塔,实现影像数据和元数据入库,建立高效的索引机制;根据窗口显示范围,调取合理的金字塔层数据,并对数据进行缓冲和实施处理显示;最后,设计元数据的管理.最终实现影像数据和元数据信息的一体化管理.  相似文献   

对提高导航型GPS定位精度之工作方法的探讨     

周新力  范志勇  羊春华 《测绘科学》2008,33(3):87-89

论文主要介绍了导航型GPS坐标转换参数的计算方法和测量误差的改正方法。该方法的要点是通过实测多个公共点来计算坐标转换参数,以此获得较好的转换精度;并进一步对观测结果加以误差改正,从而提高其定位精度。  相似文献   

“3S”技术在四川生态环境动态监测中的应用研究   总被引：2，自引：1，他引：1  

郑泽忠  范东明  夏清  邵怀勇  曹云刚 《测绘科学》2008,33(3):165-166

为有效实现四川省生态环境的动态监测,运用RS、GIS和GPS技术,以2004年中巴资源卫星(CBERS-02)遥感影像数据为信息源,2000年TM遥感影像解译的数据为基础,对2004年遥感影像进行解译,修改2000年数据库;手持GPS接收机,在野外对解译成果进行验证,更新数据库;利用GIS技术的空间分析功能,提取出2000～2004年期间土地利用/覆被变化信息,得到2000～2004年期间四川省高精度的土地利用/覆被变化数据库。最后对四川省土地利用/覆被变化信息进行分析,对四川省生态环境的下一步研究指名了方向。  相似文献   

Mechanism of Secondary Pore Formation and Prediction of Favorable Reservoir of Paleogene in Jiyang Sag,Eastern China     

Lü Xixue 《中国地质大学学报(英文版)》2008,19(6):675-684

Jiyang (济阳) sag is an oil rich basin,consisting of Huimin (惠民),Dongying (东营),Zhanhua (沾化),and Chezhen (车镇) depressions.The elastic rock of Paleogene has undergone early and middle diagenetic stages and now the main clastic reservoir is in the middle diagenetic stage.Primary and secondary pores are developed in Paleogene sandstone,the latter is generated from the dissolution of feldspar and calcite cement in rocks owing to the organic acid from the maturated source rock,but the materials dissolved are different in different depressions.The reservoir secondary pores of Dongying depression are generated from the dissolution of calcite cement,the ones of Zhanhua and Huimin depressions from the dissolution of feldspar,the secondary pores of Chezhen depression from the dissolution of feldspar in upper section,and the dissolution of calcite cement in the lower section of Paleogene,respectively.The secondary pores are developed in two depths and the depth goes down from west to east,from south to north in Jiyang sag.The major controlling factors for secondary pore development are maturity and location of source rock.Lastly,the favorable reservoirs are evaluated according to reservoir buried depth,sedimentation,and diagenesis.The reservoir with high quality is located in the northern and central parts in Dongying depression; there are some good reservoirs in Gndao (孤岛),Gudong (孤东),and Gunan (孤南) areas in Zhanhua depression,and the favorable reservoirs are located in the north steep slope and the south gentle slope of Chezhen depression and central uplift,south gentle slope of Huimin depression.  相似文献