检索结果-南通市图书馆

Spatiotemporal variations of parameters of internal solitary waves in the northern South China Sea

Journal of Oceanology and Limnology 2024年第2期42卷 421-438页

作者： Yu’ang LIU Yifei JIANG Xiaojiang ZHANG Zhiyuan WANG Yu CAO Huizan WANG college of Meteorology and oceanography National University of Defense TechnologyChangsha 410000China

The dynamic parameters for internal solitary waves(ISWs)derived from the extended Korteweg-de Vries(eKdV)equation play an important role in the understanding and prediction of ISWs.The spatiotemporal variations of the dynamic parameters of the ISWs in the northern South China Sea(SCS)were studied based on the reanalysis of long-term temperature and salinity datasets.The results for spectrum analysis show that there are definite geographical differences for the periodic variation of the parameters:in shallow water,all parameters vary with a wave period of one year,while in deep water wave components of the parameters at other frequencies exist.Using wavelet analysis,the wavelet power spectral densities in deep water exhibited an inter-annual variation pattern.For example,the wave component of the dispersion coefficient with a wave period of about half a year reached its power peak once every two years.Based on previous work,this inter-annual variation pattern was deduced to be caused by dynamic processes.In further work on the regulatory mechanisms,empirical orthogonal function(EOF)decomposition was performed.It was found that the modes of the dispersion coefficient have different geographical distributions,explaining the reason why the wave components in different frequencies appeared in different locations.The numerical simulation results confirm that the variations in the parameters of the ISWs derived from the eKdV equation could affect the waveforms significantly because of changes in the polarity of the ISWs.Therefore,the periodic variations of the dynamic parameters are related to the geographical location because of dynamic processes operating.

关键词： internal solitary waves(ISWs) dynamic parameters eKdV equation spatiotemporal variation polarity empirical orthogonal function(EOF)decomposition

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

MetaPINNs:Predicting soliton and rogue wave of nonlinear PDEs via the improved physics-informed neural networks based on meta-learned optimization

引用

Chinese Physics B 2024年第2期33卷 96-107页

作者：郭亚楠曹小群宋君强冷洪泽 college of Meteorology and oceanography National University of Defense TechnologyChangsha 410073China college of Computer National University of Defense TechnologyChangsha 410073China Naval Aviation University Huludao 125001China

Efficiently solving partial differential equations(PDEs)is a long-standing challenge in mathematics and physics research.In recent years,the rapid development of artificial intelligence technology has brought deep learning-based methods to the forefront of research on numerical methods for partial differential equations.Among them,physics-informed neural networks(PINNs)are a new class of deep learning methods that show great potential in solving PDEs and predicting complex physical phenomena.In the field of nonlinear science,solitary waves and rogue waves have been important research topics.In this paper,we propose an improved PINN that enhances the physical constraints of the neural network model by adding gradient information constraints.In addition,we employ meta-learning optimization to speed up the training process.We apply the improved PINNs to the numerical simulation and prediction of solitary and rogue waves.We evaluate the accuracy of the prediction results by error analysis.The experimental results show that the improved PINNs can make more accurate predictions in less time than that of the original PINNs.

关键词： physics-informed neural networks gradient-enhanced loss function meta-learned optimization nonlinear science

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Hyperspectral remote sensing identification of marine oil spills and emulsions using feature bands and double-branch dual-attention mechanism network

引用

Journal of Oceanology and Limnology 2024年第3期42卷 728-743页

作者： Ning ZHANG Junfang YANG Shanwei LIU Yi MA Jie ZHANG college of oceanography and Space Informatics China University of PetroleumQingdao 266580China First Institute of oceanography Ministry of Natural ResourcesQingdao 266061China Technology Innovation Center for Ocean Telemetry Ministry of Natural ResourcesQingdao 266061China

The accurate identification of marine oil spills and their emulsions is of great significance for emergency response to oil spill pollution.The selection of characteristic bands with strong separability helps to realize the rapid calculation of data on aircraft or in orbit,which will improve the timeliness of oil spill emergency monitoring.At the same time,the combination of spectral and spatial features can improve the accuracy of oil spill monitoring.Two ground-based experiments were designed to collect measured airborne hyperspectral data of crude oil and its emulsions,for which the multiscale superpixel level group clustering framework(MSGCF)was used to select spectral feature bands with strong separability.In addition,the double-branch dual-attention(DBDA)model was applied to identify crude oil and its emulsions.Compared with the recognition results based on original hyperspectral images,using the feature bands determined by MSGCF improved the recognition accuracy,and greatly shortened the running time.Moreover,the characteristic bands for quantifying the volume concentration of water-in-oil emulsions were determined,and a quantitative inversion model was constructed and applied to the AVIRIS image of the deepwater horizon oil spill event in 2010.This study verified the effectiveness of feature bands in identifying oil spill pollution types and quantifying concentration,laying foundation for rapid identification and quantification of marine oil spills and their emulsions on aircraft or in orbit.

关键词： hyperspectral image spectral analysis dimensionality reduction multiscale superpixel level group clustering framework(MSGCF) double-branch dual-attention(DBDA)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Plant photobiology:From basic theoretical research to crop production

引用

Journal of Integrative Plant Biology 2024年第5期66卷 847-848页

作者： Hongtao Liu Jigang Li college of Life Sciences and oceanography Shenzhen UniversityShenzhen 518061China State Key Laboratory of Plant Environmental Resilience College of Biological SciencesChina Agricultural UniversityBeijing 100193China

As one of the most important environmental signals for plants,light plays a profound role in regulating virtually every aspect of plant growth and development.Light signals are perceived by plants via several families of photoreceptors,among which phytochromes are responsible for absorbing the red(R)and far-red(FR)wavelengths(600–750 nm),cryptochromes(CRYs)perceive the blue(B)/ultraviolet-A(UV-A)wavelengths(320–500 nm),and UV RESISTANCE LOCUS 8(UVR8)is a recently-characterized UV-B(280–320 nm)photoreceptor.

关键词： UVR8 photoreceptor development.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The underlying mechanism of variety–water–nitrogen–stubble damage interactions on yield formation in ratoon rice with low stubble height under mechanized harvesting

引用

Journal of Integrative Agriculture 2024年第3期23卷 806-823页

作者： Jingnan Zou Ziqin Pang Zhou Li Chunlin Guo Hongmei Lin Zheng Li Hongfei Chen Jinwen Huang Ting Chen Hailong Xu Bin Qin Puleng Letuma Weiwei Lin Wenxiong Lin college of Life Sciences Fujian Agriculture and Forestry University(FAFU)/Fujian Key Laboratory for Agroecological Processes and Safety MonitoringFuzhou 350002China college of Agriculture FAFU/Fujian Key Laboratory for Crop Physiology and Molecular EcologyFuzhou 350002China Institute of oceanography College of Geography and OceanographyMinjiang UniversityFuzhou 350108China Crop Science Department The National University of LesothoRoma 00100Lesotho The Agricultural Extension Station of Pucheng County Nanping 353400China

Agronomic measures are the key to promote the sustainable development of ratoon rice by reducing the damage from mechanical crushing to the residual stubble of the main crop, thereby mitigating the impact on axillary bud sprouting and yield formation in ratoon rice. This study used widely recommended conventional rice Jiafuzhan and hybrid rice Yongyou 2640 as the test materials to conduct a four-factor block design field experiment in a greenhouse of the experimental farm of Fujian Agricultural and Forestry University, China from 2018 to 2019.The treatments included fertilization and no fertilization, alternate wetting and drying irrigation and continuous water flooding irrigation, and plots with and without artificial crushing damage on the rice stubble. At the same time, a 13C stable isotope in-situ detection technology was used to fertilize the pot experiment. The results showed significant interactions among varieties, water management, nitrogen application and stubble status.Relative to the long-term water flooding treatment, the treatment with sequential application of nitrogen fertilizer coupled with moderate field drought for root-vigor and tiller promotion before and after harvesting of the main crop, significantly improved the effective tillers from low position nodes. This in turn increased the effective panicles per plant and grains per panicle by reducing the influence of artificial crushing damage on rice stubble and achieving a high yield of the regenerated rice. Furthermore, the partitioning of 13C assimilates to the residual stubble and its axillary buds were significantly improved at the mature stage of the main crop, while the translocation rate to roots and rhizosphere soil was reduced at the later growth stage of ratooning season rice. This was triggered by the metabolism of hormones and polyamines at the stem base regulated by the interaction of water and fertilizer at this time. We therefore suggest that to achieve a high yield of ratoon rice with low stubble height under mechanized harvest

关键词： mechanized harvesting ratoon rice rice stubble yield attributes

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Improved Simulation of Summer Heavy Rainfall over Beijing and Henan by the YHGSM with Updated Subgrid Orographic Parameters

引用

Journal of Meteorological Research 2024年第3期38卷 504-529页

作者： Yingjie WANG Jianping WU Kaijun REN college of Computer Science and Technology National University of Defense Technology college of Meteorology and oceanography National University of Defense Technology

In numerical weather prediction(NWP), the parameterization of orographic drag plays an important role in representing subgrid orographic effects. The subgrid orographic parameters are the key input to the parameterization of orographic drag. Currently, the subgrid orographic parameters in most NWP models were produced based on elevation datasets generated many years ago, with a coarse resolution and low quality. In this paper, using the latest high-quality elevation data and considering the applicable scale range of the subgrid orographic parameters, we construct the orographic parameters, including the subgrid orographic standard deviation, anisotropy, orientation, and slope, that are required as input to the orographic gravity wave drag(OGWD) parameterization. Finally, we introduce the newly constructed orographic parameters into the Yin-He Global Spectral Model(YHGSM), optimize the description of the orographic effect in the model, and improve the simulation of two typical heavy rainfall events in Beijing and Henan.

关键词： subgrid orographic parameters orographic drag heavy rainfall Yin-He Global Spectral Model (YHGSM) parameterization

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Trend of Storm Surge Induced by Typical Landfall Super Typhoons During 1975–2021 in the Eastern China Sea

引用

Journal of Ocean University of China 2024年第2期23卷 277-286页

作者： LUO Feng WANG Yi TAO Aifeng SHI Jian WANG Yongzhi ZHANG Chi college of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Nantong Ocean and Coastal Engineering Research Institute Hohai UniversityNantong 226000China Key Laboratory of Ministry of Education for Coastal Disaster and Protection Hohai UniversityNanjing 210098China college of Meteorology and oceanography National University of Defense TechnologyChangsha 410073China The First Institute of oceanography MNRQingdao 266061China

Climate change affects the activity of global and regional tropical cyclones(TCs).Among all TCs,typical super typhoons(STYs)are particularly devastating because they maintain their intensity when landing on the coast and thus cause casualties,economic losses,and environmental damage.Using a 3D tidal model,we reconstructed the typhoon(TY)wind field to simulate the storm surge induced by typical STYs.The TY activity was then analyzed using historical data.Results showed a downtrend of varying degrees in the annual frequency of STYs and TCs in the Western North Pacific(WNP)Basin,with a significant trend change observed for TCs from 1949 to 2021.A large difference in the interannual change in frequency was found between STYs and TCs in the WNP and Eastern China Sea(ECS).Along the coast of EC,the frequency of landfall TCs showed a weak downtrend,and the typical STYs showed reverse micro growth with peak activity in August.Zhejiang,Fujian,and Taiwan were highly vulnerable to the frontal hits of typical STYs.Affected by climate change,the average lifetime maximum intensity(LMI)locations and landfall locations of typical STYs in the ECS basin showed a significant poleward migration trend.In addition,the annual average LMI and accumulated cyclone energy showed an uptrend,indicating the increasing severity of the disaster risk.Affected by the typical STY activity in the ECS,the maximum storm surge area also showed poleward migration,and the coast of North China faced potential growth in high storm surge risks.

关键词： storm surge super typhoons tropical cyclones eastern China Sea poleward migration

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Simulated Indonesian Throughflow in Makassar Strait across the SODA3 products

引用

Acta Oceanologica Sinica 2024年第1期43卷 80-98页

作者： Tengfei Xu Zexun Wei Haifeng Zhao Sheng Guan Shujiang Li Guanlin Wang Fei Teng Yongchui Zhang Jing Wang First Institute of oceanography/Key Laboratory of Marine Science and Numerical Modeling Ministry of Natural ResourcesQingdao 266061China Laboratory for Regional oceanography and Numerical Modeling Qingdao Marine Science and Technology CenterQingdao 266237China college of Meteorology and oceanography National University of Defense TechnologyChangsha 410073China CAS Key Laboratory of Ocean Circulation and Waves Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of ScienceQingdao 266071China

The Indonesian Throughflow(ITF), which connects the tropical Pacific and Indian oceans, plays important roles in the inter-ocean water exchange and regional or even global climate variability. The Makassar Strait is the main inflow passage of the ITF, carrying about 77% of the total ITF volume transport. In this study, we analyze the simulated ITF in the Makassar Strait in the Simple Ocean Data Assimilation version 3(SODA3) datasets. A total of nine ensemble members of the SODA3 datasets, of which are driven by different surface forcings and bulk formulas, and with or without data assimilation, are used in this study. The annual mean water transports(i.e.,volume, heat and freshwater) are related to the combination of surface forcing and bulk formula, as well as whether data assimilation is employed. The phases of the seasonal and interannual variability in water transports cross the Makassar Strait, are basically consistent with each other among the SODA3 ensemble members. The interannual variability in Makassar Strait volume and heat transports are significantly correlated with El Ni?oSouthern Oscillation(ENSO) at time lags of-6 to 7 months. There is no statistically significant correlation between the freshwater transport and the ENSO. The Makassar Strait water transports are not significantly correlated with the Indian Ocean Dipole(IOD), which may attribute to model deficiency in simulating the propagation of semiannual Kelvin waves from the Indian Ocean to the Makassar Strait.

关键词： Indonesian Throughflow Simple Ocean Data Assimilation(SODA) El Ni?o-Southern Oscillation(ENSO) Indian Ocean Dipole(IOD) data assimilation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Biogeochemistry of sedimentary organic matter in the Yongjiang River estuary in the southern part of Hangzhou Bay,China,since the Late Pleistocene

引用

Journal of Oceanology and Limnology 2024年第3期42卷 772-786页

作者： Dongqin HUANG Xiaolong LI Zilong LI Pei Sun LOH Jianxiong HU Jianfang CHEN Yuan-Pin CHANG Chin-Wen YANG Qin GAO Institute of Marine Geology and Resources Ocean CollegeZhejiang UniversityZhoushan 316021China Ministry of Water Resources of the People’s Republic of China Beijing 100054China Key Laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Department of oceanography Sun Yat-sen UniversityKaohsiung 80424China

A sediment core(YJK19-02)collected from the southern outlet of Hangzhou Bay near the Yongjiang River estuary in East China was analyzed for grain size,lignin,bulk elemental composition,stable carbon isotope,and rare earth elements(REEs)to determine the sources and diagenesis of sedimentary organic matter(OM)of the estuary and adjacent areas since the Late Pleistocene.δ^(13)C values(-24.80‰–-23.60‰),total organic carbon/total nitrogen(TOC/TN)molar ratios(8.00–12.14),and light rare earth element/heavy rare earth element ratios(LREE/HREE=8.34–8.91)revealed the predominance of terrestrial sources of OM,mainly from the Changjiang(Yangtze)River.The lignin parameters of syringyl/vanillyl(S/V=0.20–0.73)and cinnamyl/vanillyl(C/V=0.03–0.19)ratios indicate the predominance of nonwoody angiosperms,and the vanillic acid/vanillin ratios[(Ad/Al)_(V)=0.32–1.57]indicate medium to high degrees of lignin degradation.An increasing trend ofΛ(total lignin in mg/100-mg OC)values from ca.14500 a BP to ca.11000 a BP reflected the increase in temperature during the Late Pleistocene.However,a time lag effect of temperature on vegetation abundance was also revealed.The relatively higher and stableΛvalues correspond to the higher temperature during the mid-Holocene from ca.8500 a BP to ca.4500 a BP.Λvalues decreased from ca.4000 a BP to the present,corresponding to historical temperature fluctuations during this time.Our results show that the vegetation abundance in the Yongjiang River Basin since the Late Pleistocene was related to the temperature fluctuation duo to climate change.

关键词： Yongjiang River estuary sedimentary organic matter lignin environmental change Late Pleistocene

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Impacts of Ice-Ocean Stress on the Subpolar Southern Ocean:Role of the Ocean Surface Current

引用

Advances in Atmospheric Sciences 2024年第2期41卷 293-309页

作者： Yang WU Zhaomin WANG Chengyan LIU Liangjun YAN School of Information Engineering Nanjing Xiaozhuang UniversityNanjing 211171China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China college of oceanography Hohai UniversityNanjing 210098China

The mechanical influences involved in the interaction between the Antarctic sea ice and ocean surface current(OSC)on the subpolar Southern Ocean have been systematically investigated for the first time by conducting two simulations that include and exclude the OSC in the calculation of the ice-ocean stress(IOS), using an eddy-permitting coupled ocean-sea ice global model. By comparing the results of these two experiments, significant increases of 5%, 27%, and 24%, were found in the subpolar Southern Ocean when excluding the OSC in the IOS calculation for the ocean surface stress,upwelling, and downwelling, respectively. Excluding the OSC in the IOS calculation also visibly strengthens the total mechanical energy input to the OSC by about 16%, and increases the eddy kinetic energy and mean kinetic energy by about38% and 12%, respectively. Moreover, the response of the meridional overturning circulation in the Southern Ocean yields respective increases of about 16% and 15% for the upper and lower branches;and the subpolar gyres are also found to considerably intensify, by about 12%, 11%, and 11% in the Weddell Gyre, the Ross Gyre, and the Australian-Antarctic Gyre, respectively. The strengthened ocean circulations and Ekman pumping result in a warmer sea surface temperature(SST), and hence an incremental surface heat loss. The increased sea ice drift and warm SST lead to an expansion of the sea ice area and a reduction of sea ice volume. These results emphasize the importance of OSCs in the air-sea-ice interactions on the global ocean circulations and the mass balance of Antarctic ice shelves, and this component may become more significant as the rapid change of Antarctic sea ice.

关键词： subpolar Southern Ocean Antarctic sea ice ice-ocean stress air-sea-ice-ocean interaction ocean surface current MITgcm-ECCO2

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：