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Acta Oceanologica Sinica 2020年第9期39卷 133-139页

作者： Yanan Tian Xiao Han Jingwei Yin Hongxia Chen Qingyu Liu Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001China Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001China College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Naval Research Academy Beijing 100161China

An improved least mean square/fourth direct adaptive equalizer(LMS/F-DAE)is proposed in this paper for underwater acoustic communication in the *** is able to process complex-valued baseband signals and has better equalization performance than *** the sparsity feature of equalizer tap coefficients,an adaptive norm(AN)is incorporated into the cost function which is utilized as a sparse *** norm constraint changes adaptively according to the amplitude of each *** small-scale coefficients,the sparse constraint exists to accelerate the convergence *** large-scale coefficients,it disappears to ensure smaller equalization *** performance of the proposed AN-LMS/F-DAE is verified by the experimental data from the 9th Chinese National arctic Research *** results show that compared with the standard LMS/F-DAE,AN-LMS/F-DAE can promote the sparse level of the equalizer and achieve better performance.

关键词： underwater acoustic communication the arctic direct adaptive equalizer adaptive norm

Interlinking the Hotspot Track in the arctic and its Implications for Paleo-plate Reconstrution

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 822-831页

作者： LIU Zhonglan LI Jianghai LIU Chiheng LI Weibo ZHANG Hongwei The Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of EducationSchool of Earth and Space SciencesPeking University Lamont Doherty Earth Observatory Columbia University Institute of Oil & Gas Peking University

The Siberian-Icelandic hotspot track is the only preserved continental hotspot track. Although the track and its associated age progression between 160 Ma and 60 Ma are not yet well understood, this section of the track is closely linked to the tectonic evolution of Amerasian Basin, the Alpha-Mendeleev Ridge and Baffin Bay. Using paleomagnetic data, volcanic structures and marine geophysical data, the paleogeography of arctic plates （Eurasian plate, North American Plate, Greenland Plate and Alaska Microplate） was reconstructed and the Siberian-Icelandic hotspot track was interlinked between 160 Ma and 60 Ma. Our results suggested that the Alpha-Mendeleev Ridge could be a part of the hotspot track that formed between 160 Ma and 120 Ma. During this period, the hotspot controlled the tectonic evolution of Baffin Bay and the distribution of mafic rock in Greenland. Throughout the Mesozoic Era, the aforementioned arctic plates experienced clockwise rotation and migrated northeast towards the North Pacific. The vertical influence from the ancient Icelandic mantle plume broke this balance, slowing down some plates and resulting in the opening of several ocean basins. This process controlled the tectonic evolution of the arctic.

关键词： hotspot track large igneous province paleogeography reconstruction Alpha-Mendeleevridge the arctic

Composition index of n-alkanes and paleoenvironmental study in sediments of the arctic

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Acta Oceanologica Sinica 2001年第4期20卷 535-551页

作者：卢冰周怀阳王自磐陆斗定 Key Lab of Submarine Geoscience of State Oceanic Administration Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China

This paper reports different concentration patterns of n-alkanes distribution in the sedi- ments from the Chukchi Sea, the Bering Sea in the arctic. Factor statistical analysis method is used for studying the source of n-alkanes and paleoenvironment. The result shows that n-alkanes is in the range of nC15-nC33 and n-alkane distribution patterns are characterized by two modes. The first mode belongs to the higher molecular with MH being nC25-nC27, CPI > 1 and with remarkable odd-even dominance. They are of terrigenous plant origin. The second one belongs to lower carbon range with MH being nC17 -nC20, CPI > 1 and with indistinct odd-even dominance. Therefore they are contributed by marine bio- logicla inputs. The contribution of land origin is larger than that of marine source. Pr/Ph is lower than 1 in the investigated area, which indicates the depositional environment of reducing reaction with lower oxygen. The result of factor analysis has good agreement with composition characteristics of n-alkanes in the sediment.

关键词： the arctic n-alkanes factor analysis paleoenvironment

Evaluation of a regional climate model for atmospheric simulation over arctic river basins

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Chinese Journal of Oceanology and Limnology 2008年第4期26卷 425-433页

作者：马艳陈尚华锋魏和林 D.H.BROMWICH Qingdao Meteorological Bureau First Institute of Oceanography SOA National Centers for Environmental Prediction/NOAA Byrd Polar Research Center the Ohio State University Columbus

Evaluation on a regional climate model was made with five-month atmospheric simulations over the arctic river basins. The simulations were performed with a modified mesoscale model, Polar MM5 coupled to the NCAR Land Surface Model （LSM） to illustrate the skill of the coupled model （Polar MM5＋LSM） in simulating atmospheric circulation over the arctic river basins. Near-surface and upper-air observations were used to verify the simulations. Sensitivity studies between the Polar MM5 and Polar MM5＋LSM simulations revealed that the coupled model could improve the forecast skill for surface variables at some sites. In addition, the extended evaluations of the coupled model simulations on the North American arctic domain during December 15, 2002 to May 15, 2003 were carried out. The time series plots and statistics of the observations and Polar MM5＋LSM simulations at six stations for near-surface and vertical profiles at 850 hPa and 500 hPa were analyzed. The model was found capable of reproducing the observed atmospheric behavior in both magnitude and variability, especially for temperature and near-surface wind direction.

关键词： evaluation Polar MM5+LSM the arctic climate modeling

Study on Particle Filter Based Terrain Aided Navigation under the Ultra-low Resolution Map of the arctic

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Study on Particle Filter Based Terrain Aided Navigation unde...

The Hydromedusae and its distribution in Chukchi Sea and adjacent southern edge waters of Canada Basin, arctic Ocean

第三十九届中国控制会议

作者： Yanji Liu Guichen Zhang Run Lu Mengwei Chen Merchat Marine College Shanghai Maritime University

The ultra-low resolution underwater terrain map of the arctic region reduces the positioning and navigation ability of the underwater vehicle relying on terrain aided navigation. To study the navigation ability of AUVs under the ultra-low resolution terrain map, a TAN（Terrain-Aided Navigation） system based on the classical PF（particle filter） is constructed. Based on the TAN system, the effects of various parameters on the filter navigation accuracy are studied. By comparative analysis,the range of reasonable parameter set is obtained. The simulation results show that the PF-TAN system has strong robustness, and by setting parameters of PF reasonably, the AUV will perform great ability on path tracking under an ultra-low resolution map.

关键词： Terrain Aided Navigation Particle Filter Coarse Terrain Map the arctic

来源： cnki会议评论

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Chinese Journal of Polar Science 2001年第2期12卷 133-144页

作者： Zhang Jinbiao ( Third Institute of Oceanography SOA

The present paper is based on materials collected in Chukchi Sea and adjacent southern edge waters of Canada Basin, arctic Ocean during the period from July to August 1999 on the icebreaker, the R/V “Xuelong”, by the Chinese First arctic Scientific Expedition. Totally, 8 species of pelagic Hydromedusae were identified, of which 4 species belonged to Anthomedusae, 2 species to Leptomedusae, 1 species to Trachymedusae and 1 species to Narcomedusae, the Neoturris breviconis is recorded for the first time in Chukchi Sea. Their principal morphological characteristics are described and illustrated. The 8 species of Hydromedusae occurring in the Chukchi Sea were all cold water species, of which 6 species belong to neritic species and 2 species to ocean species. According to the geographic distribution of species, they may be divided into three groups: arctic species, arctic-boreal species and Boreal-temperate species. From the view-point of zoogeography, species from these waters belong to the arctic *** abundance of Hydromedusae in Chukchi Sea was generally low, with a mean value of 108 ind.*10-2*m-3. Rathkea octopunctata and Aglantha digitale were dominant species. From the view-point of vertical distribution Aglantha digitale is inhabiting in the depth of 0 300 m and with the maximum in the depth of 50 m to 100 m.

关键词： Canada Basin the Chukchi Sea morphological characteristics geographic distribution vertical distribution species of belong to dominant species the arctic mean value cold water

A possible mechanism of the Scandinavian ozone loss

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Progress in Natural Science:Materials International 2001年第4期11卷 50-55页

作者：邹捍周立波季崇萍王维蹇泳啸吴瑞欢 Beijing 100029 China Chinese Academy of Sciences Institute of Atmospheric Physics Xiaoshan 311200 Xiaoshan Meteorological Bureau

Satellite data analysis shows an important arctic ozone loss over the Scandinavia, with - 50 DU in winter, equivalent to 15% of the total ozone over this region. The study shows a possible mechanism causing the ozone loss. The North Atlantic current carries the heat energy northwards, and causes a relatively high surface temperature a-long the Scandinavia. The high temperature over the east of North Atlantic heats the atmosphere, induces an upward mass lifting, and therefore causes an ozone divergence near 330癒 isoentropic surface, which leads to a decline in the total ozone.

关键词： ozone the arctic North Atlantic current.

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Editorial Statement

Advances in Atmospheric Sciences 2006年第4期23卷 542-542页

作者： WU Guoxiong WANG Huijun Da-Lin ZHANG Co-Chief Editors

At the request of Dr. Hideharu AKIYOSHI of the National Institute for Environmental Studies (NIES) of Japan and with the apology of Dr. ZHOU Libo for his misconduct, we hereby announce that the paper of 'Middle-High Latitude N2O Distributions Related to the arctic Vortex Breakup', authored by ZHOU Libo,ZOU Han, and GAO Yongqi, be retracted from Volume 23, No. 2, March 2006 of Advances in Atmospheric Sciences (AAS) on page number 215-223.

关键词： the arctic

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白鲸转播北极数据资料

海外英语 2003年第5期 19-页

作者： Larry O'Hanlon

　　European oceanographers(海洋学者) have found a new way to explore ocean currents under the arctic ice: they' ve recruited wild beluga whales.……

关键词：白鲸转播北极 ocean currents the arctic 学者海洋