汕头港外拦门沙整治技术和功效     

黄建维  詹清光 《海洋工程》2000,18(4):55-62

汕头港外拦门沙是制约该港进一步发展的主要障碍,在对工程海域环境泥沙论证基础上,进一步对工程泥沙问题进行论证和预报,如拦门沙整治后的演变趋,开挖航道的回淤和导流 沙功效等。工程实施期间及完工后进行多年的现场跟踪观测表明,各项工程泥沙问题的预报均获得良好的印证,本文还介绍了外拉门沙整治技术方面的经验,包括运用单导堤改变工程海域水沙营运动力局和泥沙输移方向,导堤的长度和高度,沿堤流和顶冲流的整治,航道工  相似文献   

圣安德烈斯地震活动的成因     

Keer  RA 克尔 《国际地震动态》1992,(4):32-33,F004

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激活联想灵感 培养分析能力     

詹清流 《地理教学》2001,(2):41

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世界氧化镁市场综述     

詹庚申 《江苏地质科技情报》1992,(5):22-23

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本刊首次收到磁盘一打印件稿件     

詹庚申 《江苏地质》1991,(1)

自《江苏地质》1990年第3、4期连续刊出本刊优先发排微机磁盘一打印件稿件的信息以来,陆续有一些作、读者前来询问有关细节。1991年3月5日我刊首次收到江阴市建筑设计院陈玉林寄来的磁盘及打印件,1991年3月22日又收到南京大学刘松玉等的磁盘及打印件。这表明一些作者已开始利用我刊对磁盘一打印件稿件实行的倾斜政策,为加快推出自己的科研成果服务。我刊已优先将上述稿件送审,如通过终审,我刊将履行优先发排的诺言。有必要指出,我刊所指的打印件包括 PC 机、长城机以及四通打字机等自动编辑机用的打  相似文献   

新的断层图像所暗示的旧金山渗地区的地震     

Kerr.  RA 张春艳 《国际地震动态》1990,(12):26-27

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水情实况在微机屏幕上的图示及局部放大技术     

朱建英  詹道强 《水文》1990,(4):48-49

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818-01专题区域数据处理中心网络系统的设计与建立   总被引：1，自引：0，他引：1  

周智海  詹易生  曹东 《海洋技术学报》2001,20(1):27-34

本文综述了上海海洋环境立体监测和信息服务系统中的一级数据处理中心网络系统的设计与集成，并形成了区域性海洋环境立体监测和信息服务网络系统设计模式，为我国海洋环境立体监测系统建议奠定技术基础。  相似文献   

海岸工程物理模拟介绍     

Dalr.  RA 高恒庆 《海岸工程》1996,15(1):54-58

主要叙述了在海岸工程研究中经常采用的两种物理模型：定床模型与动床模型。  相似文献   

The influence of acoustic emissions for underwater data transmission on the behaviour of harbour porpoises (Phocoena phocoena) in a floating pen     

Kastelein RA  Verboom WC  Muijsers M  Jennings NV  van der Heul S 《Marine environmental research》2005,59(4):287-307

To prevent grounding of ships and collisions between ships in shallow coastal waters, an underwater data collection and communication network is currently under development: Acoustic Communication network for Monitoring of underwater Environment in coastal areas (ACME). Marine mammals might be affected by ACME sounds since they use sounds of similar frequencies (around 12 kHz) for communication, orientation, and prey location. If marine mammals tend to avoid the vicinity of the transmitters, they may be kept away from ecologically important areas by ACME sounds. One marine mammal species that may be affected in the North Sea is the harbour porpoise. Therefore, as part of an environmental impact assessment program, two captive harbour porpoises were subjected to four sounds, three of which may be used in the underwater acoustic data communication network. The effect of each sound was judged by comparing the animals' positions and respiration rates during a test period with those during a baseline period. Each of the four sounds could be made a deterrent by increasing the amplitude of the sound. The porpoises reacted by swimming away from the sounds and by slightly, but significantly, increasing their respiration rate. From the sound pressure level distribution in the pen, and the distribution of the animals during test sessions, discomfort sound level thresholds were determined for each sound. In combination with information on sound propagation in the areas where the communication system may be deployed, the extent of the 'discomfort zone' can be estimated for several source levels (SLs). The discomfort zone is defined as the area around a sound source that harbour porpoises are expected to avoid. Based on these results, SLs can be selected that have an acceptable effect on harbour porpoises in particular areas. The discomfort zone of a communication sound depends on the selected sound, the selected SL, and the propagation characteristics of the area in which the sound system is operational. In shallow, winding coastal water courses, with sandbanks, etc., the type of habitat in which the ACME sounds will be produced, propagation loss cannot be accurately estimated by using a simple propagation model, but should be measured on site. The SL of the communication system should be adapted to each area (taking into account bounding conditions created by narrow channels, sound propagation variability due to environmental factors, and the importance of an area to the affected species). The discomfort zone should not prevent harbour porpoises from spending sufficient time in ecologically important areas (for instance feeding areas), or routes towards these areas.  相似文献