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论清末“制洋器”的历史进步性 被引量:1
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作者 王永进 《郑州轻工业学院学报(社会科学版)》 2005年第5期24-27,共4页
清末“制洋器”在历史上有着极其重要的地位与作用。其历史进步性主要表现在:在清末制洋器的过程中,我国建立起一大批军事工厂,生产了大量的近代枪炮与战舰,加强了中国的防御体系与抵抗侵略的能力,在思想上也起到了启蒙作用。
关键词 洋务运动 洋器 近代国防
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从输入洋器到消化制度的“洋气”——以近代岭南报刊小说书写为中心
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作者 梁冬丽 《广西社会科学》 CSSCI 2019年第11期145-150,共6页
近代岭南报刊小说书写了深入人心的“洋气”。在物质层面,由古代书写珍奇“洋货”,变而描写与生产、交通、生活密切相关的器具,但并未详写洋务派所倡导的“坚船利炮”。在人物形象层面,化想象异域为写实视角,不再白描传奇化的洋人形象,... 近代岭南报刊小说书写了深入人心的“洋气”。在物质层面,由古代书写珍奇“洋货”,变而描写与生产、交通、生活密切相关的器具,但并未详写洋务派所倡导的“坚船利炮”。在人物形象层面,化想象异域为写实视角,不再白描传奇化的洋人形象,而是描摹有自豪的宗教信仰、有执着的考究精神、有坚韧的匠心、有富于普世情怀的洋人,或是展现骄横跋扈的特权者、无耻的入侵者。在制度层面,以西式教育、新闻纸为传输途径,生发中国人独立、民主、自由、平等、博爱等思想,并引发上层管理阶层与下层百姓变革政体的心理。 展开更多
关键词 洋器 洋人 洋气 近代岭南报刊小说
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论清末“制洋器”的历史进步性
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作者 王永进 《长江论坛》 2005年第5期51-53,57,共4页
清末“制洋器”在历史上有着极其重要的地位与作用。其历史进步性主要表现为在制洋器的过程中,清政府建立起一大批军事工厂,生产了大量的近代枪炮与战舰,加强了大清国的防御体系与抵抗侵略的能力。同时,引进与传播了近代西方科学技术与... 清末“制洋器”在历史上有着极其重要的地位与作用。其历史进步性主要表现为在制洋器的过程中,清政府建立起一大批军事工厂,生产了大量的近代枪炮与战舰,加强了大清国的防御体系与抵抗侵略的能力。同时,引进与传播了近代西方科学技术与思想文化。 展开更多
关键词 清末 洋器 进步性
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Research on the Testing Methods of Instrumental System in the Marine Magnetic Survey 被引量:1
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作者 边刚 刘雁春 +2 位作者 于波 肖付民 卞光浪 《Marine Science Bulletin》 CAS 2007年第2期1-11,共11页
Testing methods of instrumental system in the marine magnetic survey have been studied in this paper, and the feasibility of each method has been testified by the observed data. The conclusion shows that the method br... Testing methods of instrumental system in the marine magnetic survey have been studied in this paper, and the feasibility of each method has been testified by the observed data. The conclusion shows that the method brought out can effectively eliminate the systematic error caused by the instrumental system, and greatly improve the surveying precision and the reliability of the survey results. 展开更多
关键词 Marine magnetic survey instrumental system testing method
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A seafloor electromagnetic receiver for marine magnetotellurics and marine controlled-source electromagnetic sounding 被引量:7
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作者 陈凯 魏文博 +2 位作者 邓明 伍忠良 余刚 《Applied Geophysics》 SCIE CSCD 2015年第3期317-326,466,共11页
In planning and executing marine controlled-source electromagnetic methods, seafloor electromagnetic receivers must overcome the problems of noise, clock drift, and power consumption. To design a receiver that perform... In planning and executing marine controlled-source electromagnetic methods, seafloor electromagnetic receivers must overcome the problems of noise, clock drift, and power consumption. To design a receiver that performs well and overcomes the abovementioned problems, we performed forward modeling of the E-field abnormal response and established the receiver's characteristics. We describe the design optimization and the properties of each component, that is, low-noise induction coil sensor, low-noise Ag/AgCI electrode, low-noise chopper amplifier, digital temperature-compensated crystal oscillator module, acoustic telemetry modem, and burn wire system. Finally, we discuss the results of onshore and offshore field tests to show the effectiveness of the developed seafloor electromagnetic receiver and its performance: typical E-field noise of 0.12 nV/m/rt(Hz) at 0.5 Hz, dynamic range higher than 120 dB, clock drift lower than 1 ms/day, and continuous operation of at least 21 days. 展开更多
关键词 MCSEM seafloor EM receiver seafioor electric field sensor chopper amplifier acoustic telemetry modem
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Research of Marine Sensor Web Based on SOA and EDA 被引量:2
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作者 JIANG Yongguo DOU Jinfeng +1 位作者 GUO Zhongwen HU Keyong 《Journal of Ocean University of China》 SCIE CAS 2015年第2期261-268,共8页
A great deal of ocean sensor observation data exists, for a wide range of marine disciplines, derived from in situ and remote observing platforms, in real-time, near-real-time and delayed mode. Ocean monitoring is rou... A great deal of ocean sensor observation data exists, for a wide range of marine disciplines, derived from in situ and remote observing platforms, in real-time, near-real-time and delayed mode. Ocean monitoring is routinely completed using sensors and instruments. Standardization is the key requirement for exchanging information about ocean sensors and sensor data and for comparing and combining information from different sensor networks. One or more sensors are often physically integrated into a single ocean ‘instrument' device, which often brings in many challenges related to diverse sensor data formats, parameters units, different spatiotemporal resolution, application domains, data quality and sensors protocols. To face these challenges requires the standardization efforts aiming at facilitating the so-called Sensor Web, which making it easy to provide public access to sensor data and metadata information. In this paper, a Marine Sensor Web, based on SOA and EDA and integrating the MBARI's PUCK protocol, IEEE 1451 and OGC SWE 2.0, is illustrated with a five-layer architecture. The Web Service layer and Event Process layer are illustrated in detail with an actual example. The demo study has demonstrated that a standard-based system can be built to access sensors and marine instruments distributed globally using common Web browsers for monitoring the environment and oceanic conditions besides marine sensor data on the Web, this framework of Marine Sensor Web can also play an important role in many other domains' information integration. 展开更多
关键词 ocean Sensor networks ocean observing systems marine sensor web web service SOA sensor web enablement(SWE) EDA
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Three-Dimensional Ocean Sensor Networks:A Survey 被引量:21
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作者 WANG Yu LIU Yingjian GUO Zhongwen 《Journal of Ocean University of China》 SCIE CAS 2012年第4期436-450,共15页
The past decade has seen a growing interest in ocean sensor networks because of their wide applications in marine research,oceanography,ocean monitoring,offshore exploration,and defense or homeland security.Ocean sens... The past decade has seen a growing interest in ocean sensor networks because of their wide applications in marine research,oceanography,ocean monitoring,offshore exploration,and defense or homeland security.Ocean sensor networks are generally formed with various ocean sensors,autonomous underwater vehicles,surface stations,and research vessels.To make ocean sensor network applications viable,efficient communication among all devices and components is crucial.Due to the unique characteristics of underwater acoustic channels and the complex deployment environment in three dimensional(3D) ocean spaces,new efficient and reliable communication and networking protocols are needed in design of ocean sensor networks.In this paper,we aim to provide an overview of the most recent advances in network design principles for 3D ocean sensor networks,with focuses on deployment,localization,topology design,and position-based routing in 3D ocean spaces. 展开更多
关键词 ocean sensor networks underwater sensor networks three-dimensional sensor networks ocean applications 3D de-ployment topology design LOCALIZATION position-based routing
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Lead-Lag Connection of the Atlantic Multidecadal Oscillation (AMO) with East Asian Surface Air Temperatures in Instrumental Records 被引量:10
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作者 LI Shuanglin LUO Fei-Fei 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第3期138-143,共6页
The authors analyzed the lead-lag connection of the Atlantic Multidecadal Oscillation (AMO) with East Asian surface air temperatures (EATs) using instrumental records, and compared the results with the Pacific Decadal... The authors analyzed the lead-lag connection of the Atlantic Multidecadal Oscillation (AMO) with East Asian surface air temperatures (EATs) using instrumental records, and compared the results with the Pacific Decadal Oscillation (PDO). The maximum correlation was found when EATs led the AMO by five to seven years (with a correlation coefficient of 0.72, whereas the correlation coefficient was 0.91 when the AMO led EATs by 24-28 years). This is different from the PDO, which mostly correlated with EATs when the PDO led EATs by 13-15 years (with a correlation coefficient of 0.67, whereas the correlation coefficient was 0.76 when EATs led the PDO by 24-26 years). The PDO led the AMO by 19-21 years (with a correlation coefficient of 0.71, whereas the correlation coefficient was 0.84 when the AMO led the PDO by 16-18 years). These results support a previous understanding that EATs positively correlate with the AMO, and imply that the observed East Asian warming trend may have been slowing down since the early 2010s. 展开更多
关键词 EATs AMO PDO instrumental records
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New Developments in Maritime Communications: a Comprehensive Survey 被引量:7
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作者 Chen Weigang Yang Jinsheng +1 位作者 Ma Jianguo Li Si 《China Communications》 SCIE CSCD 2012年第2期31-42,共12页
This paper summarizes the requirements for modem maritime wireless communication networks in the marine environments including the sea- to-sea and sea-to-shore communication scenarios. The existing maritime wireless c... This paper summarizes the requirements for modem maritime wireless communication networks in the marine environments including the sea- to-sea and sea-to-shore communication scenarios. The existing maritime wireless communication sys- tems are presented and the development of the state-of-the-art maritime communication systems is surveyed. Furthermore, a hierarchical and integrated maritime network architecture is proposed to satisfy the increasing various classes of services which demand different Quality of Service (QoS). Finally, the open issues for further development of maritime communications are identified. 展开更多
关键词 maritime wireless communications dig-ital high frequency communications digital veryhigh frequency communications satellite communi-cations hierarchical and integrated maritime net-work
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A NEW BIOGENIC SULFIDE CHEMICAL SENSOR FOR MARINE ENVIRONMENTAL MONITORING AND SURVEY 被引量:1
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作者 宋金明 赵卫东 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2001年第3期282-286,共5页
A new convenient sulfide electrochemical sensor for marine environmental in situ monitoring and real time survey was developed. The new sensor based on a solid Ag 2S membrane electrode has outstanding chemical sensiti... A new convenient sulfide electrochemical sensor for marine environmental in situ monitoring and real time survey was developed. The new sensor based on a solid Ag 2S membrane electrode has outstanding chemical sensitivity and stability. It responds to the activity of sulfide ions according to a Nernstian slope of -31mV/decade. The sensor can be used to determine the total concentration of sulfides ( C T) by calibrating the pH value of the solution to a standard pH. The practical measurement range for total sulfide concentration is 0.1-10 mg/L in seawater. The sensor has a very low potential drift (<4mV) during two months in 0.1 mg/L sulfide seawater. This paper describes the preparation of the sensitive membrane and some main properties of the sensor. 展开更多
关键词 SULFIDE chemical sensor marine monitoring and survey
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Monte Carlo Simulation of in situ Gamma-Spectra Recorded by Na I(Tl) Detector in the Marine Environment 被引量:4
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作者 WANG Yiming ZHANG Yingying +4 位作者 WU Ning WU Bingwei LIU Yan CAO Xuan WANG Qian 《Journal of Ocean University of China》 SCIE CAS 2015年第3期471-474,共4页
To develop a NaI (T1) detector for in situ radioactivity monitoring in the marine environment and enhance the confidence of the probability of the gamma-spectrum analysis, Monte Carlo simulations using the Monte Car... To develop a NaI (T1) detector for in situ radioactivity monitoring in the marine environment and enhance the confidence of the probability of the gamma-spectrum analysis, Monte Carlo simulations using the Monte Carlo N-Particle ( MNCP ) code were performed to provide the response spectra of some interested radionuclides and the background spectra originating from the natural radionuclides in seawater recorded by a NaI (T1) detector. A newly developed 75 mm × 75 mm NaI (T1) detector was calibrated using four reference radioactive sources 137Cs, 60Co, 40K and 54Mn in the laboratory before the field measurements in seawater. A simulation model was established for the detector immersed in seawater. The simulated spectra were all broadened with Gaussian pulses to reflect the statistical fluctuations and electrical noise in the real measurement. The simulated spectra show that the single-energy photons into the detector are mostly scattering low-energy photons and the high background in the low energy region mainly originates from the Compton effect of the high energy y-rays of natural radionuclides in seawater. The simulated background spectrum was compared with the experimental one recorded in field measurement and they seem to be in good agreement. The simulation method and spectra can be used for the accurate analysis of the filed measurement results of low concentration radioactivity in seawater. 展开更多
关键词 Monte Carlo simulation marine radioactivity monitoring NaI (T1) detector response spectra background spectra
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Application of a Zero-speed Fin Stabilizer for Roll Reduction of a Marine Robot near the Surface
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作者 Yannan Gao Hongzhang Jin Shengbin Zhou 《Journal of Marine Science and Application》 2012年第2期228-235,共8页
A zero-speed fin stabilizer system was developed for rolling control of a marine robot.As a robot steering device near the sea surface with low speed,it will have rolling motion due to disturbance from waves.Based on ... A zero-speed fin stabilizer system was developed for rolling control of a marine robot.As a robot steering device near the sea surface with low speed,it will have rolling motion due to disturbance from waves.Based on the working principle of a zero-speed fin stabilizer and a marine robot’s dynamic properties,a roll damping controller was designed with a master-slave structure.It was composed of a sliding mode controller and an output tracking controller that calculates the desired righting moment and drives the zero-speed fin stabilizer.The methods of input-output linearization and model reference were used to realize the tracking control.Simulations were presented to demonstrate the validity of the control law proposed. 展开更多
关键词 zero-speed fin stabilizer roll reduction input-output linearization master-slave structure marine robot
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Properties and organic activation of ocean clay in the East Pacific
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作者 Peiping Zhang Xiaoguo Chi +3 位作者 Chunyan Tian Baojun Wang Huahua Lü Xuefa Shi 《Global Geology》 2006年第1期19-29,共11页
In order to make use of ocean clay reasonably and excavate its potential applications the properties of ocean clay in Chinese investigating area of the East Pacific have been tested with the chemical analysis, XRFS, I... In order to make use of ocean clay reasonably and excavate its potential applications the properties of ocean clay in Chinese investigating area of the East Pacific have been tested with the chemical analysis, XRFS, ICP/MAS, granulometry and SSA, etc. The results show that the clay sediments of this area are rich in clay minerals, fine granularity, bigger SSA, bigger water absorbability and lower ion changing ability etc. To improve the adaptability of ocean clay and macromolecule materials, using the dry milling method with silane, aluminate, stearic acid coupling agents etc the properties of ocean clay are improved. The effect has been evaluated by testing the water absorbing of the modified ocean clay and their dispersing in paraffin liquid. The result is that KH550 is better than any other active reagents, and the best activation technics is that 1.5% (volume) of KH550 quantity, 20min of milling time. The DTA, XRD, SEM and IR analyses and SSA testing show that the organic activation can not change the mineral structure but can densify the structure of clay, and activation mechanism is chemical covered mainly and chemical combined secondly. 展开更多
关键词 ocean clay organic activation structure PROPERTY
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Simulated Heat Sink in the Southern Ocean and Its Contribution to the Recent Hiatus Decade
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作者 OU Nian-Sen LIN Yi-Hua BI Xun-Qiang 《Atmospheric and Oceanic Science Letters》 CSCD 2015年第3期174-178,共5页
A set of numerical experiments is designed and carried out to understand a heat sink in the Southern Ocean in the recent hiatus decade. By using an oceanic general circulation model, the authors focus on the contribut... A set of numerical experiments is designed and carried out to understand a heat sink in the Southern Ocean in the recent hiatus decade. By using an oceanic general circulation model, the authors focus on the contributions from two types of forcing: wind stress and thermohaline forcing. The simulated results show that the heat sink in the upper Southern Ocean comes mainly from thermohaline forcing; while in the deeper layers, wind stress forcing also plays an important role. These different contributions may be due to different physical processes for the heat budget. The combination of these two types of forcing shows a significant heat sink in the Southern Ocean in the recent hiatus decade, and this is consistent with the observations and conclusions of a similar recently published study. 展开更多
关键词 heat sink Southem Ocean wind stress forc- ing thermohaline forcing OGCM
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Enhancing the Performance of the Marine and Tidal Current Converters Using DC-DC Boost Converter 被引量:1
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作者 Emad M. Ahmed Masahito Shoyama 《Journal of Energy and Power Engineering》 2012年第3期478-484,共7页
Due to the highly demand on the renewable energy sources as a free and a clean power resource, extracting energy from unsteady flow using marine and tidal current turbines has a distinct focusing nowadays. For their r... Due to the highly demand on the renewable energy sources as a free and a clean power resource, extracting energy from unsteady flow using marine and tidal current turbines has a distinct focusing nowadays. For their resource characteristic, extracting energy from marine/tidal current needs a simple and robust converter, which could overcome the drawbacks of the mechanical system such as gearbox and enhance conversion system stability. In this paper a new AC-DC-AC conversion system has been proposed. The new conversion system contains a middle stage DC-DC boost converter, which boost the generated rectified DC voltage higher enough that can enable the PWM inverter to generate the required voltage with the synchronized frequency. In order to investigate the efficient performance of the proposed conversion system especially at low current speed compared to the conventional one, different operating conditions have been studied. Moreover, the effect of including boost converter on the THD (total harmonic distortion) has also been checked. The new conversion system presents its capability to enhance and improve system performance not only with low current speed but also with high current speed. 展开更多
关键词 Renewable energy marine and tidal current energy AC-DC-AC converter DC-DC boost converter.
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Proper Management of Standards Formulation for Marine Survey Instrument Products
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作者 Li Fang,Tang Hairong and Yang Zheling 《China Standardization》 2009年第6期38-44,共7页
The challenges of the ocean working environment and conditions require that marine instrumentsand equipment be highly reliable and environmentally adaptable.The various parts and componentsof marine instruments should... The challenges of the ocean working environment and conditions require that marine instrumentsand equipment be highly reliable and environmentally adaptable.The various parts and componentsof marine instruments should be interchangeable,so as to reduce product costs and reasonably economizethe use of energy and material resources.This paper intruduces the importance of formulating marine instrumentproduct standards,the present conditions and problems of marine product standards,and proposesrelated measures and suggestions to sovle the problems. 展开更多
关键词 marine instrument product standards marine monitoring high-quality marine technology
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Reconstruction Model of Ocean Observing Complex Virtual Instrument
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作者 QIU Zhijin GUO Zhongwen +3 位作者 WANG Yu HU Tong LIU Chao LI Ting 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第5期1159-1170,共12页
With the newly proposed Global Ocean Observing Integration, ocean observing scope has been expanded from the region to the global, therefore the need of large-scale ocean observing system integration has become more a... With the newly proposed Global Ocean Observing Integration, ocean observing scope has been expanded from the region to the global, therefore the need of large-scale ocean observing system integration has become more and more urgent. Currently, ocean observing systems enabled ocean sensor networks are commonly developed by different organizations using specific technologies and platforms, which brings several challenges in ocean observing instrument (OOI) access and ocean observing system seamless integration. Furthermore, the development of ocean observing systems often suffers from low efficiency due to the complex prograrmning and debugging process. To solve these problems, a novel model, Complex Virtual Instrument (CVI) Model, is proposed. The model provides formal definitions on observing instrument description file, CVI description file, model calculation method, development model and interaction standard. In addition, this model establishes mathematical expressions of two model calculation operations, meanwhile builds the mapping relationship between observing instrument description file and CVI description file. The CVI based on the new model can achieve automatic access to different OOIs, seamless integration and communication for heterogeneous environments, and further implement standardized data access and management for the global unified ocean observing network. Throughout the development, integration and application of such CVI, the rationality and feasibility of the model have been evaluated. The results confirm that the proposed model can effectively implement heterogeneous system integration, improve development efficiency, make full usage of reusable components, reduce development cost, and enhance overall software system quality. We believe that our new model has great significance to promote the large-scale ocean observing system integration. 展开更多
关键词 ocean observing complex virtual instrument seamless integration model calculation development platform
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Subthermocline anticyclonic gyre east of Mindanao and its relationship with the Mindanao Undercurrent
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作者 宋丽娜 李元龙 +1 位作者 刘传玉 王凡 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第6期1303-1318,共16页
The quasi-permanent anticyclonic gyre (ACG) east of Mindanao is a dominant feature of the subthermocline circulation in the southem Philippine Sea, and it is believed closely associated with the continuous northward... The quasi-permanent anticyclonic gyre (ACG) east of Mindanao is a dominant feature of the subthermocline circulation in the southem Philippine Sea, and it is believed closely associated with the continuous northward alongshore flow of the Mindanao Undercurrent (MUC). In this study, the structure and variability of this ACG were investigated using the 1950-2012 output of the Oceanic General Circulation Model for the Earth Simulator (OFES), which can reproduce well the structure of the climatological intermediate-layer circulation and satellite-observed sea level variations in the southern Philippine Sea. Between 26.8-27.3 ao, the ACG covers a large area from the Mindanao coast to 131 ~E and from 3~N to 10~N. Its anticyclonic flow structure is unrelated to the surface Halmahera Eddy. The eddy-resolving simulation of the OFES revealed that the ACG consists of two components. The southern ACG (SACG) is centered at -6~N, while the northern ACG (NACG) is centered at -10~N. Seasonal and interannual variations of the ACG are linked to the variations of the northward MUC transport along the Mindanao coast, and the role of the SACG is more important than the NACG. Stronger (weaker) ACGs lead to greater (smaller) MUC transport. On the interannual timescale, the SACG shows a spectrum peak at 4-8 years, while the NACG has enhanced power within the 3-5-year band. A lead-lag correlation analysis indicates that interannual variations of the ACGs and the MUC transport are partly associated with the E1 Nifio-Southern Oscillation. Possible causes for the ACG variability are discussed. 展开更多
关键词 subthermocline circulation anticyclonic gyre Mindanao Undercurrent seasonal and interannual variability Halmahera Eddy
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Accommodation Vessels
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作者 Miguel Lamas Pardo Rodrigo Perez Fernandez 《Journal of Shipping and Ocean Engineering》 2012年第6期327-339,共13页
This technical paper considers the vessels used today in the sea and marine industries to provide somewhere to stay for people in semi-permanent accommodation at sea: the floating hotels. These structures have mainly... This technical paper considers the vessels used today in the sea and marine industries to provide somewhere to stay for people in semi-permanent accommodation at sea: the floating hotels. These structures have mainly been developed to hold the activities of the offshore oil and gas industry, although in coastal areas they are widely used for several purposes, mainly as commercial hotels, but with a quite different philosophy of use. The purpose of this paper is to show how the term flotel is used to denominate very different craft that, while serving the same purpose, have a totally different configuration according to the place where they are located: in protected waters in coastal areas, in benign and shallow waters of the open ocean or in the harsh environments of deep waters, etc.. 展开更多
关键词 Floating hotel coastal areas accommodation vessel/barge.
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The Upper Mixed Layer during Coastal Upwelling Events on the Northern Portugal Shelf
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作者 ZUOJuncheng SHENGHong +1 位作者 AlvaroPeliz SantosA.Miguel 《Journal of Ocean University of Qingdao》 2003年第2期147-154,共8页
The upper mixed layer (UML) depth obtained from temperature is very close to that from density:the maximum is about 15m. This indicates that temperature is a good indicator of mixed layer during measurements. When the... The upper mixed layer (UML) depth obtained from temperature is very close to that from density:the maximum is about 15m. This indicates that temperature is a good indicator of mixed layer during measurements. When the surface heat flux is balanced by a cross-shore heat flux, the surface mixed layer depth obtained from the WM model (Weatherly and Martin, 1978),hPRT, is roughly the same as observed. The mixed layer depth calculated from the PWP model (Price, Weller and Pinkel, 1986) is close to the depth obtained from thermistor chain temperature data. The results show that both the WM model and PWP model can provide a good estimate of stratification in the study area during the cruise. The value of log( h/u3) is about 9.5 in the study area, which shows that the study area is strongly stratified in summer. Observations on the northern Portugal shelf reveal high variability in stability, giving rise to semi-diurnal, semi-monthly and diurnal oscillations, and long term variations. The fortnightly oscillations are highlighted by post-springs and post-neaps. The stirring of spring tide is reinforced by strong wind mixing which brings about complete vertical homogeneity everywhere. The semi-diurnal periodic stratification is very pronounced because the major axis of the tidal ellipse is orientated acrossshore, even though the tidal current is weak in this area, the maximum stratification is observed around the middle of ebb, and, the water at this time is much warmer. The diurnal oscillation results from the upper ocean response to heating and wind mixing when solar heating warms and stabilizes the upper ocean. There is a clear relationship between upper mixed layer depth and wind-stress magnitude at subtidal frequencies. Stronger winds result in a deeper surface mixed layer. Typically, the surface mixed layer depth lags the wind stress by 6 -12 h. 展开更多
关键词 STRATIFICATION UPWELLING upper mixed layer (UML) northern Portugal shelf
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