Consequences of growth variation in northern Baltic herring for assessment and management     

Rahikainen  Mika; Stephenson  Robert L. 《ICES Journal of Marine Science》2004,61(3):338-350

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具有匹配不确定的奇异摄动系统的鲁棒控制   总被引：2，自引：0，他引：2  

高存臣  王宪杰 《中国海洋大学学报(自然科学版)》2004,34(5):918-920

对于同时具有结构匹配不确定和系统不确定量的奇异摄动系统，利用Lyapunov稳定性理论进行了鲁棒性研究。给出了1个理想奇异摄动系统的稳定鲁棒控制也是不确定奇异摄动系统稳定控制的稳定条件和鲁棒界，讨论了鲁棒界及其随参数变化的变化范围。本文是王宪杰，高存臣已有结果的推广。  相似文献   

Precautionary control rules in US fisheries management: specification and performance     

Restrepo  V. R.; Powers  J. E. 《ICES Journal of Marine Science》1999,56(6):846-852

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住宅现浇钢筋混凝土楼板裂缝成因及防治     

王昊  于湫 《海岸工程》2007,26(2):57-61

在建筑工程中,现浇钢筋混凝土楼板出现裂缝的情况较多,这已成为影响住宅工程质量的一大通病。对其产生裂缝的原因进行了分析,并结合工程实际,就预防和综合治理提出了较全面的对策。  相似文献   

Limitations of the Korean conventional fisheries management regime and expanding Korean TAC system toward output control systems     

Jeong-Gon Ryu  Jongoh Nam  John M. Gates 《Marine Policy》2006

In this paper, we focus on the status and trends of the current Korean fisheries management regime. Specifically, this paper briefly introduces the Korean conventional fisheries management regime (KCFMR) and discusses its problems and limitations. In describing policy evolution, this paper finds reasons why the Korean government has chosen a TAC system, an output control approach, besides input control approaches in force for almost a century. This paper also describes the evolution of the Korean TAC system, which is carrying out a pivotal role in Korean fisheries development, and analyzes problems of the Korean TAC system. Finally, this paper gives a perspective on expanding the Korean TAC system toward Output Control Systems (OCSs) such as Individual Quotas (IQs), Individual Vessel Quotas (IVQs), Individual Transferable Traps (ITTs), Community Quotas (CQs), and Individual Transferable Quotas (ITQs).  相似文献   

水产饲料膨化机设计刍论     

徐钟良  陈启发 《台湾海峡》2001,20(Z1):207-211

据开发应用水产饲料膨化机实践，初步论述了膨化机生产能力与动力匹配，螺杆设计参数长径比，物料在腔内滞留时间，膨化腔设计及其温度调控，并提出改进设计的见解.  相似文献   

海水甲壳类人工育苗过程中的水质控制     

朱明  茅云翔  张学成  阎斌伦  藤亚娟 《海洋湖沼通报》2002,(4):72-75

水质控制是海水甲壳类人工育苗中的关键技术之一，但是囿于设备条件的限制而难以有效进行，本文总结出两种简便的水质检测指标；pH值和水质指示生物，并对水质控制的一般原理方法进行了初步的探讨。  相似文献   

Spatial variability in the partial pressures of CO₂ in the northern Bering and Chukchi seas   总被引：2，自引：0，他引：2  

Liqi Chen  Zhongyong Gao   《Deep Sea Research Part II: Topical Studies in Oceanography》2007,54(23-26):2619

In the summers of 1999 and 2003, the 1st and 2nd Chinese National Arctic Research Expeditions measured the partial pressure of CO₂ in the air and surface waters (pCO₂) of the Bering Sea and the western Arctic Ocean. The lowest pCO₂ values were found in continental shelf waters, increased values over the Bering Sea shelf slope, and the highest values in the waters of the Bering Abyssal Plain (BAP) and the Canadian Basin. These differences arise from a combination of various source waters, biological uptake, and seasonal warming. The Chukchi Sea was found to be a carbon dioxide sink, a result of the increased open water due to rapid sea-ice melting, high primary production over the shelf and in marginal ice zones (MIZ), and transport of low pCO₂ waters from the Bering Sea. As a consequence of differences in inflow water masses, relatively low pCO₂ concentrations occurred in the Anadyr waters that dominate the western Bering Strait, and relatively high values in the waters of the Alaskan Coastal Current (ACC) in the eastern strait. The generally lower pCO₂ values found in mid-August compared to at the end of July in the Bering Strait region (66–69°N) are attributed to the presence of phytoplankton blooms. In August, higher pCO₂ than in July between 68.5 and 69°N along 169°W was associated with higher sea-surface temperatures (SST), possibly as an influence of the ACC. In August in the MIZ, pCO₂ was observed to increase along with the temperature, indicating that SST plays an important role when the pack ice melts and recedes.  相似文献   

Persistent volcanic signature observed around Barren Island, Andaman Sea, India     

C. M. Laluraj  K. K. Balachandran  P. Sabu  S. U. Panampunnayil 《Marine Geophysical Researches》2006,27(4):283-288

This study delineates the formation of a warm pool (>34°C) of air to the west (downwind) of the active volcano of the Barren Island during October–November 2005. Barren Island is located in the Sumatra–Andaman region, about 135 km east of Port Blair, and lies within the Burma microplate, the southern tip of which experienced a submarine earthquake (M _w 9.3) causing a tsunami in December 2004. Barren Island is the only volcano, which has shown sustained eruptive activity since shortly after the Great Sumatran Earthquake of December 2004. Our observations require further corroboration to relate how submarine earthquakes activate volcanoes and how far these thermal emissions influence climate changes. Because it links global warming and climate changes to the frequent emissions from a volcano activated by submarine earthquakes, this case study is of special interest to the earth-ocean-atmosphere sciences community.  相似文献   

Adaptive optimal control of an autonomous underwater vehicle in the dive plane using dorsal fins   总被引：1，自引：0，他引：1  

Mukund Narasimhan  Sahjendra N. Singh   《Ocean Engineering》2006,33(3-4):404-416

In this paper, adaptive control of low speed bio-robotic autonomous underwater vehicles (BAUVs) in the dive plane using dorsal fins is considered. It is assumed that the model parameters are completely unknown and only the depth of the vehicle is measured for feedback. Two dorsal fins are mounted in the horizontal plane on either side of the BAUV. The normal force produced by the fins, when cambered, is used for the maneuvering. The BAUV model considered here is non-minimum phase. An indirect adaptive control system is designed for the depth control using the dorsal fins. The control system consists of a gradient based identifier for online parameter estimation, an observer for state estimation, and an optimal controller. Simulation results are presented which show that the adaptive control system accomplishes precise depth control of the BAUV using dorsal fins in spite of large uncertainties in the system parameters.  相似文献