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This study presents a novel navigation and control system allowing a biomimetic-autonomous underwater vehicle (BAUV) to track a target. A Bayesian approach using an extended Kalman filter and combined localization and environmental mapping by a BAUV are implemented. This strategy selects the best sensor measurement by choosing one of several forward-looking directions. The body of the BAUV moves in a cyclical pattern; thus, an inexpensive echo sounder can be installed on the BAUV head to detect environmental features without the need for expensive scanning devices. The localization and environmental mapping problem is then transformed into a non-linear two-point boundary value problem. Optimal policies are to maintain the accuracy of predicted states and to approach minimal observation cost by solving the control problem. A line-of-sight guidance law is utilized that drives the BAUV to the target. An approach that controls the motion of the body/caudal fin and pectoral fins of the BAUV is utilized for target tracking. Estimation, measurement, and control processes are integrated to form a working system. Experiments using a test bed BAUV confirm the effectiveness of the proposed approach. 相似文献
114.
为满足水下滑翔器连续获取海洋剖面水文动力高质量数据的应用需求,利用自主研制的电磁感应式电导率传感器,集成快速响应的热敏电阻与压力传感器,以PIC18F2520单片机为电路系统的核心控制器,设计出一种适用于水下滑翔器搭载的微型化、低功耗、重量轻的SZQ1-1新型CTD传感器。该CTD测量仪经实验室多次标定,数据质量达到海试要求。2016年10月,该CTD传感器与海鸟SBE19 Plus在青岛胶州湾进行了海试比测。海试结果证明,该CTD传感器与SBE19 Plus测量结果相近,实时获取的温、盐、深剖面数据精度满足水下滑翔器的搭载要求。 相似文献
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基于卫星遥感影像和水下地形数据,分析了近年来东山岛东南侧的岸滩演变特征。进一步,分别建立潮流、波浪、沿岸输沙数值模型,结合人类活动的影响,分析东山岛东南侧岸滩侵蚀的动力成因。研究结果表明,2002-2012年金銮湾的北侧海域海床侵蚀较为严重;1971-2003年,乌礁湾北侧湾顶呈现出侵蚀现象,2003-2012年,乌礁湾北侧湾顶由之前的侵蚀现象转变为一定的淤积趋势。主要原因如下:(1)岬角的挑流作用使得金銮湾和乌礁湾北侧岬角附近海域流速较大,容易产生冲刷侵蚀。(2)金銮湾和乌礁湾的北部波高较高,波能较大,容易遭受侵蚀。(3)金銮湾和乌礁湾北部海岸输沙强度较大,净输沙方向以自东向西为主,容易发生岸滩侵蚀。(4)20世纪90年代以来,东山岛人类活动强度增大,海滩不合理的人工建筑物、海岸防护林破坏以及养殖场的建造在一定程度上加重了侵蚀。(5)2003年后乌礁湾北侧修建了码头工程,导致近岸潮流和波浪动力有所减弱,使得侵蚀现象转变为一定的淤积。 相似文献
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Michio Ueno 《Ocean Engineering》2010,37(10):879-890
A submersible surface ship (SSS) is based on a novel concept that the SSS goes on surface like conventional ships in moderate seas but goes underwater in rough seas to the depth sufficient to avoid wave effects. The SSS has a wing system that produces downward lift to go underwater with preserving the residual buoyancy for its safety. The SSS is expected to be able to keep both safety and punctuality even if it encounters unexpected bad weather.The motion of the SSS is studied. The equations of motion are formulated and the procedures for estimating hydrodynamic derivatives are presented. The hydrodynamic derivatives are estimated for a SSS having a configuration, a hull with a pair of main wings and a pair of horizontal tail wings. Using these estimated hydrodynamic derivatives, calculation of the SSS motion is carried out.The calculation results show some specific aspects of the SSS especially for effects of the elevator of main wings and horizontal tail wings, aileron of main wings, rudder and propeller revolution. It is confirmed that the existence of static roll restoring moment and having large hull comparing with wing area play important roles in the motion of the SSS. 相似文献
117.
AQUA is an underwater hexapod robot that uses its paddles to propel itself and control its orientation. To aid in the vehicle development, a simulation was needed to predict the motion of the robot based on its paddle oscillations. The most difficult aspect of this simulation was the characterization of the forces generated by the paddles oscillating in the water. In this work, a model predicting the forces produced by an oscillating rigid paddle was developed and validated experimentally. Tests were performed on an experimental setup, which was designed and built to measure the forces and torques produced by a paddle oscillating in a water tank. Also, the forces produced by a flexible fin were determined experimentally and were compared to those generated by the rigid paddle. Finally, a simulation of the AQUA robot was developed, based on the validated rigid paddle model. 相似文献
118.
Robust diving control of an AUV 总被引:1,自引:0,他引:1
Lionel Lapierre 《Ocean Engineering》2009,36(1):92-104
Mobile systems traveling through a complex environment present major difficulties in determining accurate dynamic models. Autonomous underwater vehicle motion in ocean conditions requires investigation of new control solutions that guarantee robustness against external parameter uncertainty. A diving-control design, based on Lyapunov theory and back-stepping techniques, is proposed and verified. Using adaptive and switching schemes, the control system is able to meet the required robustness. The results of the control system are theoretically proven and simulations are developed to demonstrate the performance of the solutions proposed. 相似文献
119.
For Cconsideration ofing both the eccentric rotatable rigid body and the translational rigid body, the dynamic model of the underwater glider is derived. Dynamical behaviors are also studied based on the model and can be used as the guidance to underwater gliders design. Gibbs function of the underwater glider system is derived first, and then the nonlinear dynamic model is obtained by use of Apell Equations. The relationships between dynamical behaviors and design parameters are studied by solving the dynamic model. The spiral motion, swerving motion in three dimensions and the saw-tooth motion of the underwater glider in vertical plane are studied. Lake trials are carried out to validate the dynamic model. 相似文献
120.