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Roles of different physical processes in upper ocean responses to Typhoon Rammasun(2008)-induced wind forcing
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作者 Yuhua PEI Rong-Hua ZHANG Dake CHEN 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第4期684-692,共9页
This study investigates the roles of different physical processes in the oceanic response to tropical cyclones(TCs) in the Pacific, using an ocean general circulation model with several numerical experiments. A case s... This study investigates the roles of different physical processes in the oceanic response to tropical cyclones(TCs) in the Pacific, using an ocean general circulation model with several numerical experiments. A case study is focused on Typhoon Rammasun, which passed through the northwestern tropical Pacific in May 2008. TC-induced wind stress fields are extracted using a locally-weighted regression(Loess) method from a six-hourly Cross-Calibrated Multi-Platform satellite scatterometer wind product. By comparing model experiments with TC wind forcing being explicitly included or not, the effects of TC on the ocean are isolated in a clean way. The local oceanic response is characterized by a cooling in the surface layer that persists along the typhoon track as a cold wake, and a deepening of the mixed layer(ML). The TC-induced wind can affect the ocean through the momentum effects, the ML processes(the stirring effect on the ML depth), and heat flux(via wind speed), repectively.Analyses of numerical experiments with these different underlying processes explicitly represented or not indicate that vertical mixing and upwelling are dominant processes responsible for surface cooling, while the surface heat flux also plays a nonnegligible role. Specifically, vertical mixing, upwelling and surface heat flux account for respectively ~53%,~31% and ~16% of the sea surface temperature cooling. However, for the ML response, the vertical mixing and surface heat flux are dominant processes for the ML deepening, while the contribution from upwelling process is negligible. This study provides new insights into how TC-indcued wind forcing affects the ocean by isolating each different individual process in a clear way, which differs from previous direct heat budget analyses. 展开更多
关键词 OCEAN response to TYPHOON OCEAN modeling Vertical MIXING The TROPICAL PACIFIC
Indian Ocean Dipole–related Predictability Barriers Induced by Initial Errors in the Tropical Indian Ocean in a CGCM 预览
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作者 Rong FENG Wansuo DUAN 《大气科学进展:英文版》 SCIE CAS CSCD 2019年第6期658-668,共11页
Using GFDL CM2 p1(Geophysical Fluid Dynamics Laboratory Climate Model, version 2 p1), the effects of initial sea temperature errors on the predictability of the Indian Ocean Dipole(IOD) are explored. When initial temp... Using GFDL CM2 p1(Geophysical Fluid Dynamics Laboratory Climate Model, version 2 p1), the effects of initial sea temperature errors on the predictability of the Indian Ocean Dipole(IOD) are explored. When initial temperature errors are superimposed on the tropical Indian Ocean, a winter predictability barrier(WPB) and a summer predictability barrier(SPB) exist in IOD predictions. The existence of the WPB has a close relation with El Nin?o–Southern Oscillation(ENSO)in the winter of the growing phase of positive IOD events. That is, when ENSO exists in winter, no WPB appears in IOD predictions, and vice versa. In contrast, there is no inherent connection between the existence of the SPB and ENSO. Only the dominant spatial pattern of SPB-related initial errors is studied in this paper, which presents a significant west–east dipole pattern in the tropical Indian Ocean and is similar to that of WPB-related initial errors in previous studies. The SPB-related initial errors superimposed on the tropical Indian Ocean induce the sea surface temperature(SST) and wind anomalies in the tropical Pacific Ocean. Then, under the interaction between the Indian and Pacific oceans through the atmospheric bridge and Indonesian Throughflow, a west–east dipole pattern of SST errors appears in summer, which is further strengthened under the Bjerknes feedback and yields a significant SPB. 展开更多
关键词 PREDICTABILITY barrier INITIAL ERRORS INDIAN OCEAN Dipole INDIAN OCEAN
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Quantifying the non-conservative production of potential temperature over the past 22000 years 预览
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作者 ZHANG Cunjie HAN Xueshuang LIN Xiaopei 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第2期410-422,共13页
The energy budgets of the ocean play a crucial role in the analysis of climate change. Potential temperature is traditionally used as a conservative quantity to express variations associated with “heat” in oceanogra... The energy budgets of the ocean play a crucial role in the analysis of climate change. Potential temperature is traditionally used as a conservative quantity to express variations associated with “heat” in oceanography, such as the heat content and heat transport. However, potential temperature is usually not conserved during turbulent mixing, so the use of conservative temperature is more accurate. Based on climatological simulations under the modern and Last Glacial Maximum (LGM;~21 ka;ka=thousand years ago), as well as a transient climate simulation of the past 22 000 years, we quantify the errors induced by the neglect of the non-conservation of potential temperature in paleo-climate research for the first time. The temperature error reaches 0.9℃ near the coasts aff ected by river discharges but is much smaller in the open oceans, typically 0.03°C above the main thermocline and less than 0.01℃ elsewhere. The error of the ocean heat content (OHC) is roughly 3×10^22 J and is relatively steady over the past 22 000 years. However, the OHC increases to six times the original value during the last glacial termination from 20 ka to 7 ka. As a result, the relative OHC error decreases from 1.2% in the LGM climate to 0.14% in the modern climate. The error of the ocean meridional heat transport (OMHT) is generally smaller than 0.005 PW (1 PW=10 15 W), with very small temporal variations (typically 0.000 4 PW), and induces a relative OMHT error of typically 0.3% over the past 22 000 years. Therefore, the neglect of the non-conservation of potential temperature induces a relative error of generally less than 1% in the analyses of basin-scale climate variations. 展开更多
关键词 CONSERVATIVE TEMPERATURE potential TEMPERATURE OCEAN HEAT content OCEAN HEAT transport PALEOCLIMATE
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远海岛礁医院应急采供血机制的探究
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作者 靳冰 成海 +2 位作者 张蓉 王燕菊 蒋学兵 《中国输血杂志》 CAS 2019年第8期742-745,共4页
目的建立远海岛礁医院应急采血运行机制,保障紧急情况下伤员输血救治。方法通过查阅资料、现场考察、反复论证,依据国家、军队相关法律法规建立了应急采血实施方案、流程和'流动血库'机制,明确了组织架构和职能分工,根据不同情... 目的建立远海岛礁医院应急采血运行机制,保障紧急情况下伤员输血救治。方法通过查阅资料、现场考察、反复论证,依据国家、军队相关法律法规建立了应急采血实施方案、流程和'流动血库'机制,明确了组织架构和职能分工,根据不同情况建立了紧急备血、紧急用血和用备结合三种应急采供血保障模式。进行了应急采血分队人员编配、职责分工、业务培训和操作演练。结果三种应急采供血模式经过实践检验具有可行性。结论在远海岛礁医院建立应急采供血模式可以保障少量伤员的急救用血需求,不适用于大批量伤员抢救用血。 展开更多
关键词 远海 岛礁医院 应急采血 血液保障
Co-seismic change in ocean bottom topography:Implication to absolute global mean sea level change
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作者 Jiangcun Zhou Heping Sun +2 位作者 Jianqiao Xu Xiaodong Chen Xiaoming Cui 《大地测量与地球动力学:英文版》 2019年第3期179-186,共8页
Earthquakes perturb both the ocean bottom topography due to displacements of sea floor and the geoid due to mass redistribution, which induces the relative sea level(RSL) change. However, the relative global mean sea ... Earthquakes perturb both the ocean bottom topography due to displacements of sea floor and the geoid due to mass redistribution, which induces the relative sea level(RSL) change. However, the relative global mean sea level(GMSL) change is zero in that sea water mass is conserved. But the absolute GMSL change is not zero because earthquakes displace total ocean mass with respect to the Earth’s center of mass(CM) which remains unchanged after an earthquake. This displacement, i.e. the absolute GMSL change, may be detectable by altimetry since the satellites are orbiting around CM. In this paper, we proposed a method to estimate co-seismic absolute GMSL change caused by earthquakes based on the point dislocation theory for a spherically symmetric, non-rotating, elastic and isotropic(SNREI) Earth.This change can be directly connected to the perturbation of ocean bottom topography. We first computed co-seismic displacements as well as the change in geo-potential and solved the sea level equation to validate the insignificance of the oceans’ feedback, i.e. the loading effect due to RSL change, to co-seismic displacements. The results imply that the loading effect due to RSL change is negligible on displacements while is considerable on geoid. We then computed the absolute GMSL change caused by co-seismic vertical and horizontal displacements by making use of the integrated Green’s function method. The numerical results show that a large earthquake may raise the absolute GMSL by magnitude of sub-millimeter and the recent three large events cause GMSL to rise about one millimeter, in which the contribution from horizontal displacement is non-negligible. 展开更多
关键词 Point DISLOCATION theory SNREI earth Sea level equation ABSOLUTE GMSL Ocean BOTTOM TOPOGRAPHY
特种传感器现状趋势及对能力建设需求 预览
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作者 李庆剑 王野 +1 位作者 车静 陈信琦 《传感器与微系统》 CSCD 2019年第8期157-160,共4页
描述五类极端环境下应用的特种传感器技术,讨论各类极端环境对传感器功能和性能的劣化影响和传感器极端环境适应性技术的部分解决方案。涉及的特种传感器主要包括压力、振动、位移、温度传感器及加速度计、探空仪等。特种传感器技术发... 描述五类极端环境下应用的特种传感器技术,讨论各类极端环境对传感器功能和性能的劣化影响和传感器极端环境适应性技术的部分解决方案。涉及的特种传感器主要包括压力、振动、位移、温度传感器及加速度计、探空仪等。特种传感器技术发展对传感器研制生产能力建设提出了新的更高的要求。 展开更多
关键词 特种传感器 极端环境 温度 冲击振动 核辐射 大气 海洋
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海洋食品质量与安全科技发展趋势分析 预览
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作者 张燕霞 《现代食品》 2019年第13期116-117,124共3页
众所周知,海洋中的生物种类具有多样化的特征,而且安全风险各异,因而需要重点思考和分析。与此同时,海洋食品的生产周期通常比较长,因此,海洋食品的质量安全把控工作是非常必要的环节,这项工作的开展难度十分大。基于此,为了有效促进海... 众所周知,海洋中的生物种类具有多样化的特征,而且安全风险各异,因而需要重点思考和分析。与此同时,海洋食品的生产周期通常比较长,因此,海洋食品的质量安全把控工作是非常必要的环节,这项工作的开展难度十分大。基于此,为了有效促进海洋食品的质量与安全能够更加具有保证,能够在未来安全发展,本文对此进行了认真的思考和详细的分析。 展开更多
关键词 海洋 食品质量 安全科技 发展趋势
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Reconstruction of phytoplankton productivity and community structure in the South Yellow Sea 预览
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作者 Xi Mei Ri-hui Li +2 位作者 Xun-hua Zhang Zhong-bo Wang Yong Zhang 《中国地质(英文)》 2019年第3期315-324,共10页
The sedimentary environment and ecological system in the South Yellow Sea (SYS) changed dramatically due to sea level change caused by glacial-interglacial cycles. The authors report the use of marine biomarkers (bras... The sedimentary environment and ecological system in the South Yellow Sea (SYS) changed dramatically due to sea level change caused by glacial-interglacial cycles. The authors report the use of marine biomarkers (brassicasterol, dinosterol and C37 alkenones) and terrigenous biomarkers (C28+C30+C32 nalkanols) in core DLC70-3 from the SYS to reconstruct the variation in the phytoplankton productivity and community structure and possible mechanisms during the middle Pleistocene. The results show that the primary productivity and that of single algae presented a consistent trend for the whole core during the middle Pleistocene, which was high during interglacial periods and low during glacial periods, with the highest being in marine isotope stage (MIS) 5–9 and MIS 19–21. The main reason is that the Yellow Sea Warm Current (YSWC) carried much of high temperature, high salinity water into the SYS, causing upwelling and vertical mixing and stirring, which increased the nutrient supply in the photosynthetic layer. The phytoplankton community structure mainly showed an increase in the relative content of haptophytes in MIS 5–9 and MIS 19–21, while the relative content of diatoms and dinoflagellates decreased;there was no evidence for a haptophyte content in other stages. The results reveal a shift from a coccolitho-phoriddominated community during MIS 5 –9 and MIS 19 –21 to a diatom-dominated community during the other stages, mainly as a result of surface salinity variation, attributed to the invasion of the YSWC during high sea level periods. 展开更多
关键词 Biomarker PHYTOPLANKTON PRODUCTIVITY PHYTOPLANKTON community Ocean WARM current Global climate change Marine GEOLOGICAL survey engineering Yellow Sea China
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Wave packet solutions in a bounded equatorial ocean and its interannual and decadal variabilities 预览
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作者 Dongling Zhang Juan Zhu +1 位作者 Xu Lu Ming Zhang 《海洋学报:英文版》 SCIE CAS CSCD 2019年第3期45-59,共15页
Linearized shallow water perturbation equations with approximation in an equatorial β plane are used to obtain the analytical solution of wave packet anomalies in the upper bounded equatorial ocean. The main results ... Linearized shallow water perturbation equations with approximation in an equatorial β plane are used to obtain the analytical solution of wave packet anomalies in the upper bounded equatorial ocean. The main results are as follows. The wave packet is a superposition of eastward travelling Kelvin waves and westward travelling Rossby waves with the slowest speed, and satisfies the boundary conditions of eastern and western coasts, respectively.The decay coefficient of this solution to the north and south sides of the equator is inversely proportional only to the phase velocity of Kelvin waves in the upper water. The oscillation frequency of the wave packet, which is also the natural frequency of the ocean, is proportional to its mode number and the phase velocity of Kelvin waves and is inversely proportional to the length of the equatorial ocean in the east-west direction. The flow anomalies of the wave packet of Mode 1 most of the time appear as zonal flows with the same direction. They reach the maximum at the center of the equatorial ocean and decay rapidly away from the equator, manifested as equatorially trapped waves. The flow anomalies of the wave packet of Mode 2 appear as the zonal flows with the same direction most of the time in half of the ocean, and are always 0 at the center of the entire ocean which indicates stagnation, while decaying away from the equator with the same speed as that of Mode 1. The spatial structure and oscillation period of the wave packet solution of Mode 1 and Mode 2 are consistent with the changing periods of the surface spatial field and time coefficient of the first and second modes of complex empirical orthogonal function(EOF)analysis of flow anomalies in the actual equatorial ocean. This indicates that the solution does exist in the real ocean, and that El Ni?o-Southern Oscillation(ENSO) and Indian Ocean dipole(IOD) are both related to Mode 2.After considering the Indonesian throughflow, we can obtain the length of bounded equatorial ocean by taking the sum of that of the t 展开更多
关键词 BOUNDED EQUATORIAL OCEAN WAVE packet SOLUTIONS DECADAL variability Kelvin WAVE Rossby WAVE
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A preliminary study on an upper ocean heat and salt content of the western Pacific warm pool region 预览
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作者 Xiaoxin Yang Xiaofen Wu +1 位作者 Zenghong Liu Chunxin Yuan 《海洋学报:英文版》 SCIE CAS CSCD 2019年第3期60-71,共12页
On the basis of Argo profile data of the temperature and salinity from January 2001 to July 2014, the spatial distributions of an upper ocean heat content(OHC) and ocean salt content(OSC) of the western Pacific warm p... On the basis of Argo profile data of the temperature and salinity from January 2001 to July 2014, the spatial distributions of an upper ocean heat content(OHC) and ocean salt content(OSC) of the western Pacific warm pool(WPWP) region and their seasonal and interannual variations are studied by a cyclostationary empirical orthogonal function(CSEOF) decomposition, a maximum entropy spectral analysis, and a correlation analysis.Probable reasons for variations are discussed. The results show the following.(1) The OHC variations in the subsurface layer of the WPWP are much greater than those in the surface layer. On the contrary, the OSC variations are mainly in the surface layer, while the subsurface layer varies little.(2) Compared with the OSC, the OHC of the WPWP region is more affected by El Ni?o-Southern Oscillation(ENSO) events. The CSEOF analysis shows that the OHC pattern in mode 1 has strong interannual oscillation, with eastern and western parts opposite in phase. The distribution of the OSC has a positive-negative-positive tripole pattern. Time series analysis shows that the OHC has three phase adjustments with the occurrence of ENSO events after 2007, while the OSC only had one such adjustment during the same period. Further analysis indicates that the OHC variations are mainly caused by ENSO events, local winds, and zonal currents, whereas the OSC variations are caused by much more complex reasons. Two of these, the zonal current and a freshwater flux, have a positive feedback on the OSC change in the WPWP region. 展开更多
关键词 ocean HEAT CONTENT SALT CONTENT the western Pacific WARM POOL ARGO data
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Geochronology, Geochemistry, and Hf Isotopic Compositions of Monzogranites and Mafic-Ultramafic Complexes in the Maxingdawannan Area, Eastern Kunlun Orogen, Western China: Implications for Magma Sources, Geodynamic Setting, and Petrogenesis
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作者 Jiaming Yan Guosheng Sun +5 位作者 Fengyue Sun Liang Li Haoran Li Zhenhua Gao Lei Hua Zhengping Yan 《地球科学学刊:英文版》 SCIE CAS CSCD 2019年第2期335-347,共13页
This paper presents zircon U-Pb-Hf isotopic compositions and whole-rock geochemical data for monzogranites and mafic-ultramafic complexes of the Maxingdawannan area in the western end of the east Kunlun orogenic belt,... This paper presents zircon U-Pb-Hf isotopic compositions and whole-rock geochemical data for monzogranites and mafic-ultramafic complexes of the Maxingdawannan area in the western end of the east Kunlun orogenic belt, western China. The data are used to determine the ages, petrogenesis, magma sources, and geodynamic setting of the studied rocks. U-Pb zircon dating indicates that monzogranites and gabbros of the complexes were emplaced at 399 and 397 Ma, respectively. The monzogranites are shoshonitic, with high SiO2, Al2 O3 and total-alkali contents, and low TFeO, MgO, TiO2 and P2 O5 contents. The mafic-ultramafic complexes are characterized by low Si O2 contents. The monzogranites display enrichment in light rare-earth elements(LREE) and large-ion lithophile elements(LILE), depletion in heavy REEs(HREE) and high-field-strength elements(HFSE), and negative Eu anomalies(Eu/Eu*=0.36–0.48). The mafic-ultramafic complexes are also enriched in LREEs and LILEs, and depleted in HREEs and HFSEs, with weak Eu anomalies(Eu/Eu*=0.84–1.16). Zircon εHf(t) values for the monzogranites and mafic-ultramafic complexes range from-6.68 to 1.11 and-1.81 to 6.29, with zircon model ages of 1 812–1 319 Ma(TDM2) and 1 087–769 Ma(TDM1), respectively. Hf isotopic data indicate that primary magmas of the monzogranites are originated from partial melting of ancient lower crust during the Paleo-Mesoproterozoic, with a juvenile-crust component. Primitive magmas of the mafic-ultramafic complexes are likely originated from a depleted-mantle source modified by slab-derived fluids and contaminated by crustal components. Geochemical data and the geological setting indicate that Devonian intrusions in the Maxingdawannan area are related to northward subduction of the ProtoTethys oceanic lithosphere. 展开更多
关键词 GEOCHRONOLOGY GEOCHEMISTRY Hf isotopes Maxingdawannan Proto-Tethys Ocean
无氢四面体非晶碳膜在海水中的摩擦学性能 预览
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作者 连峰 马明明 杨忠振 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2019年第6期1098-1101,共4页
为了开发能直接应用于海洋环境的自润滑材料,在不锈钢表面制备无氢四面体非晶碳(ta-DLC)膜,分别测试和比较ta-DLC膜在海水、水和油中的摩擦学性能。结果表明:ta-DLC膜在海水中的摩擦系数小于0.1,磨痕最窄且浅,表现出最优异的摩擦学性能... 为了开发能直接应用于海洋环境的自润滑材料,在不锈钢表面制备无氢四面体非晶碳(ta-DLC)膜,分别测试和比较ta-DLC膜在海水、水和油中的摩擦学性能。结果表明:ta-DLC膜在海水中的摩擦系数小于0.1,磨痕最窄且浅,表现出最优异的摩擦学性能,其水中摩擦学性能略差于其海水中摩擦学性能,在油中摩擦学性能最差。ta-DLC膜在海水润滑领域具有广阔应用前景。 展开更多
关键词 无氢四面体非晶碳膜 海水 摩擦学性能 摩擦系数 磨痕 海洋 不锈钢
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Geochronology and geochemistry of Permo-Triassic sandstones in eastern Jilin Province(NE China):Implications for final closure of the Paleo-Asian Ocean 预览
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作者 Qingxiang Du Zuozhen Han +5 位作者 Xiaoli Shen Chao Han Zhigang Song Lihua Gao Mei Han Wenjian Zhong 《地学前缘:英文版》 CAS CSCD 2019年第2期683-704,共22页
In the eastern part of the Central Asian Orogenic Belt(CAOB) in northeastern(NE) China, scattered outcrops of molasse deposits mark the ending of an orogeny and are crucial for understanding the evolution of the Paleo... In the eastern part of the Central Asian Orogenic Belt(CAOB) in northeastern(NE) China, scattered outcrops of molasse deposits mark the ending of an orogeny and are crucial for understanding the evolution of the Paleo-Asian Ocean(PAO). However, the timing of tectonic events and the relationships among these strata remain controversial. To better constrain these geologic events, a comprehensive study of the detrital zircon U-Pb geochronology and geochemistry of the sandstones of the Kaishantun(KST) Formation and Kedao(KD) Group in eastern Jilin Province, NE China, was conducted. The KST Formation is traditionally considered a molasse deposit. The sandstones display low CIA, PIA and high ICV values and low Th/U and Rb/Sr ratios, which suggest that the rocks were derived from an immature intermediate-felsic igneous source and experienced a simple sedimentary recycling history with relatively weak chemical weathering. LA-ICP-MS U-Pb dating of detrital zircons from two samples of the KST Formation yields ages of 748-252 Ma, suggesting that the KST Formation was deposited between 254.5 Ma and 252 Ma in Late Permian. The zircons were mainly derived from the continental northern part of the North China Craton(NCC). In contrast, the U-Pb dating of detrital zircons from five samples of the KD Group yields ages of 2611-230 Ma, suggesting that the KD samples were deposited in the Early to Middle Triassic(ca. 248-233 Ma). The detrital zircon ages for the KD samples can be divided into groups with peaks at 2.5 Ga, 1.8 Ga, 800-1000 Ma, 500 Ma and 440-360 Ma, which suggest that the samples were derived from bidirectional provenances in the Jiamusi-Khanka Block and the NCC. These new data,combined with previously published results, suggest that at least three orogenic events occurred in central-eastern Jilin Province during the Early Permian(270-262 Ma), Early Triassic(254-248 Ma) and Middle-Late Triassic(242-227 Ma). The final closure of the PAO occurred during 242-227 Ma in the Middle-Late Triassic along the Changchun-Yanji sut 展开更多
关键词 DETRITAL zircon MOLASSE OROGENIC events Changchun-Yanji suture zone Paleo-Asian Ocean
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Modeling of suspended sediment by coupled wave-current model in the Zhujiang(Pearl)River Estuary 预览
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作者 Guangping Liu Shuqun Cai 《海洋学报:英文版》 SCIE CAS CSCD 2019年第7期22-35,共14页
A three-dimensional wave-current-sediment coupled numerical model is developed to understand the sediment transport dynamics in the Zhujiang(Pearl)River Estuary(ZRE),China.The model results are in good agreement with ... A three-dimensional wave-current-sediment coupled numerical model is developed to understand the sediment transport dynamics in the Zhujiang(Pearl)River Estuary(ZRE),China.The model results are in good agreement with observed data,and statistics show good model skill scores.Numerical studies are conducted to assess the scenarios of suspended sediment in the ZRE under the effects of different forcing(river discharges,waves,and winds).The model results indicate that the estuarine gravitational circulation plays an important role in the development of estuarine turbidity maximum in the ZRE,particularly during neap tides.The increased river discharge can result in a seaward sediment transport.The suspended sediment concentration(SSC)in the bottom increases with both wave bottom orbital velocity and wave height.Because of the shallow water depth,the effect of waves on sediment in the west shoal is greater than that in the east channel.The southwesterly wind-induced wave affects the SSC more than those resulting from the northeasterly wind,while the northeasterly wind-driven circulation has a slightly greater influence on the SSC than that of the southwesterly wind.However,a steady southwesterly wind condition favors the increase of the SSC in the Lingding Bay more so than a steady northeasterly wind condition.If the other forcings are same,the averaged SSC under a steady southwesterly wind condition is about 1.1 times that resulting from a steady northeasterly wind. 展开更多
关键词 sediment transport TURBIDITY Regional OCEAN Modeling System(ROMS) Zhujiang River ESTUARY
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Reducing Carbon Emission through Container Shipment Consolidation and Optimization 预览
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作者 Nang Laik Ma Kar Way Tan 《交通与运输工程:英文版》 2019年第3期111-121,共11页
Human’s impact on earth through global warming is more or less an accepted fact.Ocean freight is estimated to contribute 4-5%of global carbon emissions.Many manufacturing companies that transfer ship goods through fu... Human’s impact on earth through global warming is more or less an accepted fact.Ocean freight is estimated to contribute 4-5%of global carbon emissions.Many manufacturing companies that transfer ship goods through full container loads found themselves under-utilizing the containers and resulting in higher carbon footprint per volume shipment.One of the reasons is the choice of non-ideal container sizes for their shipments.In this paper,we first provide an Integer Programming model to minimize the companies’shipping carbon footprints by selecting the ideal container sizes appropriate for their shipment volumes.Secondly,we proposed a strategy to minimize the carbon footprint by consolidating the shipments in the same country from multiple domestic locations at a port of loading by road freight,before the international sea shipment.A mixed-Integer Programming model has been developed to determine if one should ship each shipment separately or have shipments consolidated first before being shipped.Consolidation fills up the containers more efficiently that reduces the overall carbon footprint.Computational results using real-world data indicates a significant 13.4%reduction carbon emission when selecting the optimal combinations of different sizes of containers and an additional 12.1%reduction in carbon emission when shipment consolidation is applied. 展开更多
关键词 Carbon emission data ANALYTICS CONTAINER CONSOLIDATION SUSTAINABILITY optimization ocean FREIGHT supply chain management
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An unsupervised learning approach to study synchroneity of past events in the South China Sea
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作者 Kevin C. Tse Hon-Chim Chiu +2 位作者 Man-Yin Tsang Yiliang Li Edmund Y. Lam 《地球科学前沿:英文版》 CSCD 2019年第3期628-640,共13页
Unsupervised machine learning methods were applied on multivariate geophysical and geochemical datasets of ocean floor sediment cores collected from the South China Sea. The well-preserved and continuous core samples ... Unsupervised machine learning methods were applied on multivariate geophysical and geochemical datasets of ocean floor sediment cores collected from the South China Sea. The well-preserved and continuous core samples comprising high resolution Cenozoic sediment records enable scientists to carry out paleoenvironment studies in detail. Bayesian age-depth chronological models constructed from biostratigraphic control points for the drilling sites are applied on cluster boundaries generated from two popular unsupervised learning methods: K-means and random forest. The unsupervised learning methods experimented have produced compact and unambiguous clusters from the datasets, indicating that previously unknown data patterns can be revealed when all variables from the datasets are taken into account simultaneously. A study of synchroneity of past events represented by the cluster boundaries across geographically separated ocean drilling sites is achieved through converting the fixed depths of cluster boundaries into chronological ranges represented by Gaussian density plots which are then compared with known past events in the region. A Gaussian density peak at around 7.2 Ma has been identified from results of all three sites and it is suggested to coincide with the initiation of the East Asian monsoon. Contrary to traditional statistical approach, a priori assumptions are not required for unsupervised learning, and the clustering results serve as a novel data-driven proxy for studying the complex and dynamic processes of the paleoenvironment surrounding the ocean sediment. This work serves as a pioneering approach to extract valuable information of regional events and opens up a systematic and objective way to study the vast global ocean sediment datasets. 展开更多
关键词 machine learning OCEAN SEDIMENTS UNSUPERVISED classification
Isa Secretary-General’s Statement: Isa Plays a Key Role in Regulating the Sustainable Development of Mineral Resources in a Way That Balances the Need for Minerals with Rigorous Environmental Protection 预览
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《中华海洋法学评论(中英文版)》 2019年第3期183-185,共3页
In light of recent release of the report by Greenpeace entitled‘Protect the Ocean’,which regrettably contains a series of inaccurate elements and factual mistakes,particularly in relation to the existing legal regim... In light of recent release of the report by Greenpeace entitled‘Protect the Ocean’,which regrettably contains a series of inaccurate elements and factual mistakes,particularly in relation to the existing legal regime set up by international law,ISA wishes to make a number of corrections to the report.The legal regime for the seabed beyond national jurisdiction(which covers 54%of the global ocean)is an integral and fundamental part of the international system for ocean governance under the 1982 United Nations Convention on the Law of the Sea(UNCLOS),which is often referred to as the‘constitution for the ocean’.The ISA is established by the Convention to manage the mineral resources of the deep seabed,which are designated‘the common heritage of mankind’on behalf of all humanity. 展开更多
关键词 ocean LEGAL behalf
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The Rapidly Changing Arctic and Its Impact on Global Climate 预览
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作者 ZHAO Jinping ZHONG Wenli +1 位作者 DIAO Yina CAO Yong 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第3期537-541,共5页
Arctic sea ice has significant seasonal variability. Prior to the 2000 s, it retreated about 15% in summer and fully recovered in winter. However, by the year 2007, Arctic sea ice extent experienced a catastrophic dec... Arctic sea ice has significant seasonal variability. Prior to the 2000 s, it retreated about 15% in summer and fully recovered in winter. However, by the year 2007, Arctic sea ice extent experienced a catastrophic decline to about 4.28×10^6 km^2, which was 50% lower than conditions in the 1950 s to the 1970 s(Serreze et al., 2008). That was a record low over the course of the modern satellite record, since 1979(note that the year 2012 became the new record low). This astonishing event drew wide-ranging attention in 2007-2009 during the 4 th International Polar Year. The dramatic decline of sea ice attracts many scientists’ interest and has become the focus of intense research since then. Currently, sea ice retreat is not only appearing around the marginal ice zone, but also in the pack ice inside the central Arctic(Zhao et al., 2018). In fact, premonitory signs had already been seen through other evidence. Before the disintegration of the Soviet Union, US naval submarines had been conducting an extensive survey under the sea ice and taking measurements of sea ice thickness. Their measurements revealed a gradual decrease of ice thickness to 1.8 m during winter by the end of the 20 th century, in contrast to the climatological mean of 3.1 m(Rothrock et al., 1999). However, this alarming result did not draw much attention since the Arctic was still severely cold at that time. 展开更多
关键词 ARCTIC Ocean climate change sea ice RETREAT FRESHWATER ACCUMULATION ARCTIC AMPLIFICATION global impacts
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氯盐干湿循环条件下有机阻锈剂钢筋缓蚀机制研究 预览
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作者 丁娅 周霄骋 +1 位作者 蔡景顺 马麒 《江苏建材》 2019年第5期36-38,43共4页
针对海洋潮差浪溅环境下钢筋锈蚀风险高的问题,通过试验,分析了有机阻锈剂对氯盐干湿循环环境下混凝土中氯离子扩散及混凝土中钢筋锈蚀行为的影响,结果表明,有机阻锈剂(ZX)可以有效抑制氯盐干湿循环环境下氯离子在混凝土中的扩散,并缓... 针对海洋潮差浪溅环境下钢筋锈蚀风险高的问题,通过试验,分析了有机阻锈剂对氯盐干湿循环环境下混凝土中氯离子扩散及混凝土中钢筋锈蚀行为的影响,结果表明,有机阻锈剂(ZX)可以有效抑制氯盐干湿循环环境下氯离子在混凝土中的扩散,并缓解钢筋锈蚀的快速发展。 展开更多
关键词 海洋 氯盐 阻锈技术 有机阻锈剂 钢筋
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Enhancing the observing capacity for the surface ocean by the use of Volunteer Observing Ship 预览
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作者 Zong-Pei Jiang Jiajun Yuan +1 位作者 Susan E.Hartman Wei Fan 《海洋学报:英文版》 SCIE CAS CSCD 2019年第7期114-120,共7页
Knowledge of the surface ocean dynamics and the underlying controlling mechanisms is critical to understand the natural variability of the ocean and to predict its future response to climate change.In this paper,we hi... Knowledge of the surface ocean dynamics and the underlying controlling mechanisms is critical to understand the natural variability of the ocean and to predict its future response to climate change.In this paper,we highlight the potential use of Volunteer Observing Ship(VOS),as carrier for automatic underway measuring system and as platform for sample collection,to enhance the observing capacity for the surface ocean.We review the concept,history,present status and future development of the VOS-based in situ surface ocean observation.The successes of various VOS projects demonstrate that,along with the rapid advancing sensor techniques,VOS is able to improve the temporal resolution and spatial coverage of the surface ocean observation in a highly cost-effective manner.A sustained and efficient marine monitoring system in the future should integrate the advantages of various observing platforms including VOS. 展开更多
关键词 VOLUNTEER observing SHIP SHIP of OPPORTUNITY SURFACE OCEAN in SITU observation sensor
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