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Analysis of sea level changes in the Caspian Sea related to Cosmo-geophysical processes based on satellite and terrestrial data
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作者 Vladimir Kaftan Boris Komitov Sergey Lebedev 《Geodesy and Geodynamics》 2018年第6期449-455,共7页
Analysis results of the average annual sea levels in the Caspian Sea obtained from ground and satellite observations, corresponding to solar activity characteristics, magnetic field data, and length of day are present... Analysis results of the average annual sea levels in the Caspian Sea obtained from ground and satellite observations, corresponding to solar activity characteristics, magnetic field data, and length of day are presented. Spectra of the indicated processes were investigated and their approximation models were also built. Previously assumed statistical relationships between space-geophysical processes and Caspian Sea level(CSL) changes were confirmed. A close connection was revealed between the low-frequency models of the solar and geomagnetic activity parameters and the CSL changes. Predictions extending into the next decades showed a high probability of an increase in the CSL and a decrease of the compared space-geophysical parameters. 展开更多
关键词 CSL Analysis of sea level changes in the Caspian sea related to Cosmo-geophysical processes based on satellite and terrestrial data LOD SSN
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THE FLUX OF LAND-BASED SOURCE POLLUTANTS FROM TUMEN RIVER SYSTEM ENTERING THE SEA OF JAPAN
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作者 殷兴军 尹澄清 《Chinese Geographical Science》 SCIE CSCD 1998年第3期48-54,共0页
The influence of land based source pollutants to marine ecological environment is principally in coastal or enclosed sea waters. Flux of land based source pollutants into the sea will be effected due to social and ... The influence of land based source pollutants to marine ecological environment is principally in coastal or enclosed sea waters. Flux of land based source pollutants into the sea will be effected due to social and economic development in the Tumen River basin. Pollutant type and primary pollution factor of the Tumen River in Northeast China is described by weighted coefficient method in this paper. The results indicate that the river is organic pollution type and primary pollution factor is COD. Fresh water fraction proves that the estuary is not affected by tide cycle. COD annual flux entering the Sea of Japan calculated by zero dimension model in 1993 was 90.50 ×10 3 tons. It is estimated with emission coefficient method that the COD will be 176.4 ×10 3 and 458.6 ×10 3 tons for the years of 2000 and 2010 respectively. 展开更多
关键词 Tumen RIVER COD the sea of JAPAN POLLUTION forecast land based SOURCE POLLUTANTS marine POLLUTION
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Optimal Stiffness for Flexible Connectors on A Mobile Offshore Base at Rough Sea States 被引量:1
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作者 WU Lin-jian WANG Yuan-zhan +4 位作者 WANG Yu-chi CHEN Jia-yu LI Yi LI Qing-mei XIE Tao 《China Ocean Engineering》 SCIE EI CSCD 2018年第6期683-695,共13页
This paper investigates a simplified method to determine the optimal stiffness of flexible connectors on a mobile offshore base(MOB) during the preliminary design stage. A three-module numerical model of an MOB was us... This paper investigates a simplified method to determine the optimal stiffness of flexible connectors on a mobile offshore base(MOB) during the preliminary design stage. A three-module numerical model of an MOB was used as a case study. Numerous constraint forces and relative displacements for the connectors at rough sea states with different wave angles were utilized to determine the optimized stiffness of the flexible connectors. The range of optimal stiffnesses for the connectors was obtained based on the combination and intersection of the optimized stiffness results, and the implementation steps were elaborated in detail. The percentage reductions of the optimized and optimal stiffness of the flexible connector were determined to quantitatively evaluate the decreases of the constraint force and relative displacement of the connectors compared with those calculated by using the original range of the connector stiffnesses. The results indicate the accuracy and feasibility of this method for determining the optimal stiffness of the flexible connectors and demonstrate the rationality and practicability of the optimal stiffness results. The research ideas, calculation process, and solutions for the optimal stiffness of the flexible connectors of an MOB in this paper can provide valuable technical support for the design of the connectors in similar semisubmersible floating structures. 展开更多
关键词 mobile offshore base(MOB) flexible connectors the optimal stiffness rough sea states
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苍南海域中国毛虾种群生物学特征及其资源状况
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作者 秦松 邱文致 +5 位作者 叶深 艾龙威 张明燡 范青松 张华伟 刘伟成 《海洋渔业》 北大核心 2026年第1期11-22,共12页
2022年5月、8月、11月和2023年2月,于苍南海域共采集2286尾中国毛虾(Acetes chinensis)样本,测定其体长、体质量、性别等生物学特征,并运用FiSATⅡ软件对其生长、死亡参数及资源利用状况等进行评估。结果显示:调查期间中国毛虾雌雄性比... 2022年5月、8月、11月和2023年2月,于苍南海域共采集2286尾中国毛虾(Acetes chinensis)样本,测定其体长、体质量、性别等生物学特征,并运用FiSATⅡ软件对其生长、死亡参数及资源利用状况等进行评估。结果显示:调查期间中国毛虾雌雄性比平均为1.66︰1;体长为11.2~50.1 mm,平均(35.1±6.4)mm,雌雄体长差异显著(P<0.05);最优拟合得到体质量-体长关系式W=2.2648×10^(-5)L^(2.5699),体长、体质量生长方程分别为L_(t)=49.88[1-^(e-1.5(t+0.15))]和W_(t)=0.523[1-^(e-1.5(t+0.15))]2.5699;自然死亡系数(M)为3.24a^(-1),捕捞死亡系数(F)为1.13a^(-1);开捕体长(Lc)为29.0 mm,等于最适开捕体长(L_(opt))29.0 mm;年资源开发率(E)为0.259,小于资源量下降原始水平50%的开发率(E_(0.5))(0.392)。结果表明,苍南海域中国毛虾资源处于轻度开发状态,鉴于苍南海域毛虾捕捞产业是当地渔民致富增收的支柱产业,同时我国目前实施伏季休渔毛虾限额捕捞已有成熟先例,建议可适当探索开展苍南毛虾伏季休渔限额捕捞工作。 展开更多
关键词 中国毛虾 苍南海域 性比 体长股分析法 资源开发率
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航天器基础激励SEA建模方法
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作者 马建刚 盛美萍 《航天器环境工程》 2012年第3期283-286,共4页
针对航天器力学环境试验中随机横向基础激励高频预示技术开展了建模方法的研究。首先建立典型结构的有限元模型并开展仿真计算,获取背地板面内振动数据、连接环弯曲振动数据及振动台横向振动数据;进而分别建立背地板受纵向振动约束载荷... 针对航天器力学环境试验中随机横向基础激励高频预示技术开展了建模方法的研究。首先建立典型结构的有限元模型并开展仿真计算,获取背地板面内振动数据、连接环弯曲振动数据及振动台横向振动数据;进而分别建立背地板受纵向振动约束载荷、连接环受弯曲振动约束载荷的SEA模型,并将有限元计算结果作为激励源数据,利用统计能量分析(SEA)方法开展仿真分析,得到了航天器横向基础激励SEA建模的一般方法和步骤。研究表明:横向基础激励下,可将环境试验中获取的振动台数据以弯曲波的形式施加到连接环上,进行航天器高频响应SEA预示。 展开更多
关键词 航天器 统计能量分析 有限元分析 横向基础激励 高频预示
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北极航道环境数字化服务及应用研究
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作者 邱玉宝 崔恒 +2 位作者 金泽楷 李晓婷 余淑文 《数据与计算发展前沿(中英文)》 2026年第2期82-97,共16页
【背景】气候变暖致使北极海冰持续减少,为全球交通和国际性贸易提供了新通道,北极航行已从探索阶段进入了发展期。在北冰洋少冰季、融冰或结冰期,航道环境信息的及时获取是安全航行的关键。【目的】论文旨在基于空天数据、人工智能预... 【背景】气候变暖致使北极海冰持续减少,为全球交通和国际性贸易提供了新通道,北极航行已从探索阶段进入了发展期。在北冰洋少冰季、融冰或结冰期,航道环境信息的及时获取是安全航行的关键。【目的】论文旨在基于空天数据、人工智能预报技术和综合性通航指数,发展北极航道环境信息获取、服务及数字化应用能力,构建应对北极航行安全和北极环境治理的航道环境数字化服务系统。【方法】论文围绕当前空天数据的可获取性,遴选形成了影响北极航道的环境关键变量;以传统的可通航性指数为基础,引入降水、气温、水汽、海表温度、浪高等环境因子,构建了综合性通航评估模型;研制了基于空天数据的航道环境信息服务系统,在北极航行应急响应、年度计划和中长期规划等方面提供分层次的支撑服务;系统在我国北极探索性航行和北极极端环境探险性航行服务支撑中取得了实际效果。【结论】该系统综合北极航道环境关键变量、多源空间数据、海冰预报技术、通航性评估模型,构建了航行分层服务策略,为北极航道环境信息服务、北极航行安全及环境治理提供了重要的数字化工具。 展开更多
关键词 北极航道环境 关键变量 空天信息产品 通航性评估 海冰AI预报
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基于混合ES-FE-SEA方法的中频声固耦合分析 被引量:6
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作者 吴飞 李光耀 +1 位作者 成艾国 何智成 《机械工程学报》 EI CAS CSCD 北大核心 2015年第15期67-74,共8页
结构声学的中频预测问题是一直是业界的一个难点和热点。结构声学中频响应复杂,单一确定性的低频方法和统计性的高频方法都不合适中频问题的分析与预测。针对中频结构声学问题,引入基于单元边的梯度光滑技术,软化三维声学系统的刚度,结... 结构声学的中频预测问题是一直是业界的一个难点和热点。结构声学中频响应复杂,单一确定性的低频方法和统计性的高频方法都不合适中频问题的分析与预测。针对中频结构声学问题,引入基于单元边的梯度光滑技术,软化三维声学系统的刚度,结合统计能量法,构造基于光滑有限元和统计能量法的混合方法(ES-FE-SEA)的理论框架。算例表明,新构造的混合ES-FE-SEA能够在声固耦合系统的频响分析中得到比传统的FE-SEA混合方法更好的精度。 展开更多
关键词 中频 结构声学 边光滑有限元 统计能量法 混合ES-FE-sea
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Influence of simulating deep-sea environmental factors on cathodic performance of seawater battery 被引量:4
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作者 LU Yonghong YANG Lulu +4 位作者 ZHANG Yue ZHAO Qing SANG Lin DING Fei XU Haibo 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2020年第2期334-341,共8页
A metal-dissolved oxygen seawater battery(SWB)uses metal and dissolved oxygen as the reactants,and it is ideal for use as a long-time low-power distributed power supply in deep sea,due to its advantages of open struct... A metal-dissolved oxygen seawater battery(SWB)uses metal and dissolved oxygen as the reactants,and it is ideal for use as a long-time low-power distributed power supply in deep sea,due to its advantages of open structure in service without electrolyte.However,several simulating deep-sea environmental factors,such as flow rate,dissolved oxygen concentration,and temperature of seawater may af fect the oxygen reduction reaction(ORR)rate and the stability of electrochemically modified polyacrylonitrile-based carbon fiber brush(MPAN-CFB)cathode,which was studied by steady-state polarization and galvanostatic discharge methods.In addition,the scales formed on MPAN-CFB surface were characterized by SEM and XRD.Results show that the ORR rate increased quickly with the increase of the seawater flow rate up to 3 cm/s,and then gradually stabilized.Moreover,the ORR rate was largely af fected by dissolved oxygen concentration,and the concentration of>3 mg/L was favorable.Compared with surface layer temperature of 15℃,the low temperature of deep sea(4℃)has a negligible ef fect on ORR rate.When the working current is too high,it will lead to the formation of CaCO_3 scales(aragonite)of at the cathodic surface,resulting in the decrease of ORR rate,and consequently the damage to the long-time stability of MPAN-CFB. 展开更多
关键词 seawater battery(SWB) deep sea modified polyacrylonitrile-based carbon fiber brush(MPANCFB) oxygen reduction reaction(ORR) scale formation
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Nano-LC-ESI MS/MS analysis of proteins in dried sea dragon Solenognathus hardwickii and bioinformatic analysis of its protein expression profiling 被引量:2
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作者 ZHANG Dong-Mei FENG Li-Xing +7 位作者 LI Lu LIU Miao JIANG Bao-Hong YANG Min LI Guo-Qiang WU Wan-Ying GUO De-An LIU Xuan 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2016年第9期709-713,共5页
The sea dragon Solenognathus hardwickii has long been used as a traditional Chinese medicine for the treatment of various diseases, such as male impotency. To gain a comprehensive insight into the protein components o... The sea dragon Solenognathus hardwickii has long been used as a traditional Chinese medicine for the treatment of various diseases, such as male impotency. To gain a comprehensive insight into the protein components of the sea dragon, shotgun proteomic analysis of its protein expression profiling was conducted in the present study. Proteins were extracted from dried sea dragon using a trichloroacetic acid/acetone precipitation method and then separated by SDS-PAGE. The protein bands were cut from the gel and digested by trypsin to generate peptide mixture. The peptide fragments were then analyzed using nano liquid chromatography tandem mass spectrometry(nano-LC-ESI MS/MS). 810 proteins and 1 577 peptides were identified in the dried sea dragon. The identified proteins exhibited molecular weight values ranging from 1 900 to 3 516 900 Da and p I values from 3.8 to 12.18. Bioinformatic analysis was conducted using the DAVID Bioinformatics Resources 6.7 Gene Ontology(GO) analysis tool to explore possible functions of the identified proteins. Ascribed functions of the proteins mainly included intracellular non-membrane-bound organelle, non-membrane-bounded organelle, cytoskeleton, structural molecule activity, calcium ion binding and etc. Furthermore, possible signal networks of the identified proteins were predicted using STRING(Search Tool for the Retrieval of Interacting Genes) database. Ribosomal protein synthesis was found to play an important role in the signal network. The results of this study, to best of our knowledge, were the first to provide a reference proteome profile for the sea dragon, and would aid in the understanding of the expression and functions of the identified proteins. 展开更多
关键词 sea dragon Solenognathus hardwickii Mass-spectrometry-based proteomics Bioinformatic analysis
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PREDICTION OF SEA FOG OF GUANGDONG COASTLAND USING THE VARIABLE FACTORS OUTPUT BY GRAPES MODEL 被引量:2
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作者 黄辉军 黄健 +3 位作者 刘春霞 袁金南 毛伟康 廖菲 《Journal of Tropical Meteorology》 SCIE 2011年第2期166-174,共9页
By analyzing the NCEP 1°×1° reanalysis (2004–2008), a number of predictors (factors of variables) are established with the output from the GRAPES model and with reference to the sea fog data from obser... By analyzing the NCEP 1°×1° reanalysis (2004–2008), a number of predictors (factors of variables) are established with the output from the GRAPES model and with reference to the sea fog data from observational stations (2004–2008) and field observations (2006–2008). Based on the criteria and conditions for sea fog appearance at the stations of Zhanjiang, Zhuhai and Shantou, a Model Output Statistics (MOS) scheme for distinguishing and forecasting 24-h sea fog is established and put into use for three representative coastal areas of Guangdong. As shown in an assessment of the forecasts for Zhanjiang and Shantou (March of 2008) and Zhuhai (April of 2008), the scheme was quite capable of forecasting sea fog on the coast of the province, with the accuracy ranging from 84% to 90%, the threat score from 0.40 to 0.50 and the Heidke skill from 0.52 to 0.56. 展开更多
关键词 sea fog forecast coastal Guangdong MOS-based distinguishing scheme variable predictors
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采用方向自适应密度聚类自动检测侧扫声呐图像海底线 被引量:2
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作者 王爱学 金绍华 +2 位作者 刘天阳 查文富 刘畅 《武汉大学学报(信息科学版)》 北大核心 2025年第4期674-683,698,共11页
侧扫声呐是获取海底地貌图像的主要手段之一,海底线是侧扫声呐瀑布图像最显著的特征,准确检测和跟踪海底线是侧扫声呐数据精细处理的基础。受水体环境噪声、船体、水面及水体悬浮目标散射等干扰,传统阈值法及相关图像特征检测算法难以... 侧扫声呐是获取海底地貌图像的主要手段之一,海底线是侧扫声呐瀑布图像最显著的特征,准确检测和跟踪海底线是侧扫声呐数据精细处理的基础。受水体环境噪声、船体、水面及水体悬浮目标散射等干扰,传统阈值法及相关图像特征检测算法难以实现海底线自动、准确、高效提取。充分考虑侧扫声呐海底线的边缘特性及沿航迹向密集分布的空间特点,提出了一种边缘方向适应性密度聚类和聚类链筛选相结合的海底线检测方法。该方法通过高斯一阶导卷积模板及非极大值抑制实现高噪声图像边缘梯度和方向计算以及边缘特征的细化;通过设置窄带状搜索邻域,并依据边缘梯度方向实时调整搜索邻域的长轴,以实现对方向变化的线状特征的密度聚类;通过构建基于边缘特征密度聚类的海底线检测策略,包括设定经验范围、阈值法构建聚类种子集、长链原则、排他原则、对称原则、趋势延伸原则、修复原则等,以实现海底线边缘特征的快速密度聚类成链和海底线的筛选。实验验证和对比分析的结果表明,在持续噪声、复杂悬浮物等常见水体回波干扰下,所提方法在海底线检测的准确性和稳定性上优于传统阈值方法,且单呯平均检测耗时仅为0.661 ms。所提侧扫声呐图像海底线检测方法有较好的稳定性和干扰普适性,可在侧扫声呐数据采集和事后处理中推广应用。 展开更多
关键词 侧扫声呐 海底线跟踪 密度聚类 方向自适应
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Geometries and mechanism of folds in sediments on the southern Huanghai Sea shelf
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作者 LI Xishuang LIU Baohua +1 位作者 ZHAO Yuexia LI Sanzhong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第4期23-31,共9页
Most descriptions and studies about folds have been associated with consolidated strata; fold deformation in loosely-consolidated sediments, however, has been rarely discussed. Since the Pleistocene, tectonic activiti... Most descriptions and studies about folds have been associated with consolidated strata; fold deformation in loosely-consolidated sediments, however, has been rarely discussed. Since the Pleistocene, tectonic activities have been intensive over the South Huanghai Sea (SHS) shelf, resulting in fold deformation features that are preserved in thick sediment layers. Four types of folds with different geometries have been identified on the basis of an analysis of single - channel seismic profiles from the SHS shelf region: (1) fault-propagation fold; (2) fault-drag fold; (3) transversal bending fold; and (4) multi-action-folding fold. Studies on the geometry and mechanism of the folds indicate that base faults and fault blocks control the folding patterns in loosely-consoli- dated sediments on the SHS shelf and a large quantity of pore water in sediments plays an important role in cansing the deformation of sediment layers. The continuity of deformations of fault-propagation fold and fault-drag fold indicates that there is a genetic relationship between these fold types. The potential of earthquakes induced by fault-propagation folding in the deformation zone should be taken into account in the assessment of the marine engineering geology conditions of the SHS shelf. 展开更多
关键词 FOLD loosely-consolidated sediment base fault marine engineering south Huanghai sea shelf
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基于反行波波前瞬时能量谱的深远海风电经柔直并网系统的双端行波故障测距方法 被引量:2
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作者 刘乐 陈旭明 +5 位作者 康小宁 马晓伟 李诗闯 赵勃扬 李昕盈 刘鑫 《电力自动化设备》 北大核心 2025年第3期86-94,共9页
现有的行波测距方法的精确性和可靠性受到保护采样频率、强噪声干扰、短故障距离、高过渡电阻等因素的严重影响,对此提出一种基于小波自适应阈值降噪(AWTD)和结合变分模态分解(VMD)的Hilbert变换的双端行波故障测距方法。利用AWTD算法... 现有的行波测距方法的精确性和可靠性受到保护采样频率、强噪声干扰、短故障距离、高过渡电阻等因素的严重影响,对此提出一种基于小波自适应阈值降噪(AWTD)和结合变分模态分解(VMD)的Hilbert变换的双端行波故障测距方法。利用AWTD算法对故障反行波数据进行降噪预处理。通过VMD算法提取蕴含故障距离信息的高频本征模态函数。利用Hilbert变换获得第5层本征模态函数的瞬时能量谱,并通过瞬时能量谱的最大值实现对线路两端反行波波头的标定,得到行波抵达保护测量点的精确时间,从而结合线路两端行波波速度预测故障距离。在PSCAD/EMTDC与RTDS仿真平台中搭建双端与三端典型深远海风电并网模型进行大量测试,结果表明,所提测距方法不受故障电阻、故障类型的影响,在不同采样频率、近端故障、强噪声干扰与实时仿真环境下,均能实现精准的故障定位,具有一定工程应用价值。 展开更多
关键词 深远海风电 行波故障测距 小波自适应阈值降噪 变分模态分解 HILBERT变换 瞬时能量谱
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纽约滨海韧性规划研究进展与实践综述 被引量:1
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作者 陈飞 曹诗茵 +2 位作者 蔡军 许世光 胡秦兰 《西部人居环境学刊》 北大核心 2025年第3期188-195,共8页
海平面上升冲击滨海地区安全,全球越来越多的滨海城市开展以防洪减灾为核心的韧性规划研究与实践。本文聚焦纽约滨海韧性规划研究和实践,回顾纽约市早期开展的气候变化研究,重点分析2012年“桑迪飓风”之后滨海韧性规划研究与实践,包括... 海平面上升冲击滨海地区安全,全球越来越多的滨海城市开展以防洪减灾为核心的韧性规划研究与实践。本文聚焦纽约滨海韧性规划研究和实践,回顾纽约市早期开展的气候变化研究,重点分析2012年“桑迪飓风”之后滨海韧性规划研究与实践,包括重新绘制洪水地图,颁布多项目技术指南文件、提升建筑和海岸防护要求,组织构建覆盖全域的滨海防护体系,并开展试点建设等方面内容。综合分析纽约市多年研究与实践经验,以期在构建多层次跨部门的滨海韧性研究、治理体系,建设多机构衔接的灾后保障快速响应体系,开展广泛公众参与提升公众滨海韧性的防护意识工作等方面为我国滨海韧性规划研究和实践提供借鉴。 展开更多
关键词 海平面上升 沿海洪水 滨海韧性规划 基于自然的解决方法
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Detection of the Hazards That Threaten Some Coastal Areas, and Ecosystem-Based Solution to Strengthen the Natural Defenses
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作者 Ahmed E. Rakha 《Journal of Geoscience and Environment Protection》 2022年第9期170-184,共15页
The coastal strip of the Nile delta has been vulnerable to environmental hazards. Field surveys, interpretation of Landsat enhanced thematic mapper imageries (ETM), and hydrochemistry analysis of the water samples was... The coastal strip of the Nile delta has been vulnerable to environmental hazards. Field surveys, interpretation of Landsat enhanced thematic mapper imageries (ETM), and hydrochemistry analysis of the water samples was used as methods and materials to detect the hazards associated with climate change which threaten some natural protection coastal areas of the central part of the Nile Delta and assess its magnitude. The invasion of seawaters is the main hazard due to the impacts of global warming phenomena. Elimination of the coastal dunes which act as natural defenses has been accelerating the negative impacts that have been appearing clearly on low-lying lands. Planting that protected areas of the coastal strip are considered the most suitable ecosystem-based and most beneficial solution should be authorized and adopted by the local administration to preserve those areas and adapt to these disasters. 展开更多
关键词 The Ecosystem-based Solution Climate Change sea-Level Rise Coastal Strip Natural Protection Nile Delta The Adaption PROTECTION
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ROV型深海采矿车动力学建模及路径跟踪控制研究 被引量:3
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作者 陈昱衡 张海成 +2 位作者 邹伟生 李煜 徐道临 《动力学与控制学报》 2025年第2期30-37,共8页
本文针对传统深海采矿系统中履带车操作稳定性差的瓶颈问题,研究了一种新型的遥控水下机器人(ROV)型深海采矿系统,其中ROV型深海采矿车取代了传统的履带式深海采矿车.ROV型深海采矿车由一个ROV和一个采矿机器人(MRT)组成.首先,假设ROV... 本文针对传统深海采矿系统中履带车操作稳定性差的瓶颈问题,研究了一种新型的遥控水下机器人(ROV)型深海采矿系统,其中ROV型深海采矿车取代了传统的履带式深海采矿车.ROV型深海采矿车由一个ROV和一个采矿机器人(MRT)组成.首先,假设ROV保持固定深度拖曳MRT,通过类比自行车模型,以此建立了ROV型采矿车的动力学模型.其次,提出了一种分层路径跟踪控制策略,基于ROV型采矿车的运动学模型,设计了线性模型预测控制器(LMPC)以计算收敛MRT路径跟踪偏差的虚拟控制律,下层PID控制器计算响应虚拟控制律的ROV控制输入.最后,通过数值模拟初步验证了分层路径跟踪控制策略的可行性. 展开更多
关键词 深海采矿 ROV型深海采矿系统 动力学建模 路径跟踪控制
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南极阿蒙森海一次海雾过程分析 被引量:2
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作者 江可悦 韩博 +2 位作者 孙启振 梁文骏 杨清华 《极地研究》 北大核心 2025年第2期275-284,共10页
海雾会降低能见度从而严重威胁海上活动,而南极地区的海雾观测研究相对较少。我国“雪龙”号极地科考船于2019年1月在南极阿蒙森海航行期间经历了一次较强海雾事件,本文利用期间航测数据和ERA5再分析数据,开展了本次海雾过程分析。本次... 海雾会降低能见度从而严重威胁海上活动,而南极地区的海雾观测研究相对较少。我国“雪龙”号极地科考船于2019年1月在南极阿蒙森海航行期间经历了一次较强海雾事件,本文利用期间航测数据和ERA5再分析数据,开展了本次海雾过程分析。本次海雾事件发生于2019年1月17—19日,持续时间约48 h,其中,能见度小于500 m的时段约占整个有雾时段的40%,是一次持续时间较长、强度较高的南大洋海雾个例。分析表明,本次事件的雾区受南大洋低压系统影响,由于中高层处于弱的辐合抬升,此时低空向极风带来的低纬热量与水汽在对流层底层维持了一个饱和且层结稳定的结构;与此同时,雾区海表较弱的风场抑制了湍流的垂直输送并维持了近海表大气热力结构和雾滴密度,这二者共同作用造成了该次持续较久的海雾。 展开更多
关键词 海雾 走航观测 平流作用 南极地区
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海基测控系统远程支持关键技术及应用
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作者 汪彩玲 杨学海 王钧慧 《电讯技术》 北大核心 2025年第4期537-542,共6页
海基测控是我国航天测控网重要的组成部分。当前航天器呈现爆发式增长态势,海基测控需适应高密度、高强度、高难度的需求。为提高海基测控系统任务保障、健康管理等自动化运行水平,提出了一套远程技术支持方法体系。基于海基测控系统的... 海基测控是我国航天测控网重要的组成部分。当前航天器呈现爆发式增长态势,海基测控需适应高密度、高强度、高难度的需求。为提高海基测控系统任务保障、健康管理等自动化运行水平,提出了一套远程技术支持方法体系。基于海基测控系统的特点,构建远程支持系统架构,突破智能测控平台技术、实时/事后相结合的船岸信息交互、远程故障快速定位、故障事后场景还原、专家会商协同定位以及全维度远程监控管理等关键技术。实践应用表明,该技术可有效提升装备海上检修和维护水平,降低船载人员任务值班及排故压力,实时信息传输效率提升了约21%,故障定位时间缩短了近20%。 展开更多
关键词 海基测控系统 远程支持技术 健康管理 自动化运行
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纳米蒙脱石改性海水海砂砾石混凝土轴心抗压强度试验研究
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作者 许莉 吴尚明 +2 位作者 冯奇 黄跃森 张广达 《市政技术》 2025年第12期167-176,228,共11页
为缓解现有资源匮乏问题,针对海水、海砂和砾石3类储量丰富的自然资源,开展了纳米蒙脱石改性海水海砂砾石混凝土宏观力学性能研究。通过轴向荷载试验探明了纳米蒙脱石改性海水海砂砾石混凝土试件的破坏形态和轴心抗压强度,揭示了纳米蒙... 为缓解现有资源匮乏问题,针对海水、海砂和砾石3类储量丰富的自然资源,开展了纳米蒙脱石改性海水海砂砾石混凝土宏观力学性能研究。通过轴向荷载试验探明了纳米蒙脱石改性海水海砂砾石混凝土试件的破坏形态和轴心抗压强度,揭示了纳米蒙脱石悬浊液浓度ρ(0.0%、0.1%、0.2%、0.3%)、海砂取代率(0%、50%、100%)和海水对混凝土破坏形态、峰值承载力、荷载-位移曲线、初始弹性模量和延性指数的影响规律,并构建出适用于纳米蒙脱石改性海水海砂砾石混凝土的受压本构修正模型。结果表明,试件失效发生在中部,材料力学性能得到表征,破坏损伤程度随ρ的增加而加剧;海水-海砂-砾石组试件的峰值承载力受ρ影响呈现先减小后增大的趋势;荷载-位移曲线呈现弹性、弹塑性、软化、残余4个阶段,其中海水组、海水-海砂组试件的最大变形能力随ρ的增加而提高;不同ρ下试件的受压本构修正模型曲线与试验曲线的整体趋势一致。 展开更多
关键词 钠基蒙脱石 海水海砂砾石混凝土 受压本构修正模型 轴向荷载试验
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