检索结果-南通市图书馆

Feasibility study of miniature near-infrared spectrometer for the measurement of solar irradiance within Arctic snow-cover sea ice

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2020年第9期39卷 115-124页

作者： Liwen Nan Xiaoping Wang Hangzhou Wang Hongliang Zhou Ying Chen Ocean College Zhejiang UniversityZhoushan 316021China Zhejiang Heli Electrical Engineering Co. Ltd.Taizhou 317000China

The extremely low temperature,high humidity and limited power supply pose considerable challenges when using spectrometers within the Arctic sea *** feasibility of using a miniature low-power near-infrared spectrometer module to measure solar radiation in Arctic sea ice environments was investigated in this *** and integration time dependences of the spectrometer module were examined over the entire target operating range of–50°C to 30°C,well below the specified operating range of this *** these observations,a dark output prediction model was developed to represent dark output as a function of temperature and integration ***-induced biases in the saturation output and linear operating range of the spectrometer were also *** and integration time dependences of the signal output were *** signal output correction models were developed and compared,to convert the signal output at any temperature within the operating temperature range and integration time to that measured at the reference temperature and integration *** overall performance of the spectrometer was evaluated by integrating it into a refined fiber optic spectrometry system and measuring solar irradiance distribution in the ice cover with thickness of 1.85 m in the Arctic during the 9th Chinese national Arctic research *** general shape of the measured solar irradiance above the snow surface agreed well with that measured by other commercial oceanographic *** measured optical properties of the sea ice were generally comparable to those of similar ice measured using other *** approach provides a general framework for assessing the feasibility of using spectrometers for applications in cold environments.

关键词： near-infrared spectrometer low-temperature Arctic sea ice

Measuring solar irradiance profiles in the Arctic sea ice using fiber optic spectrometry via inclined holes

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2021年第3期40卷 134-141页

作者： Zexia Qiu Hangzhou Wang Tao Li Hong Song Yuanqian Wu Tingting Yan Ying Chen Ocean College Zhejiang UniversityZhoushan 316021China key Laboratory of Physical Oceanography Ocean University of ChinaQingdao 266100China Zhejiang Heli Electrical Engineering Co. Ltd.Taizhou 317000China

An irradiance profile measurement approach and profiling system were developed to measure the solar irradiance profile of the Arctic sea ice using fiber optic *** approach involved using a miniature spectrometer to sense light signals collected and transmitted from a fiber *** fiber probe was small,and could thus move freely in inclined bore holes drilled in sea ice with its optical entrance pointing *** input-output relationship of the system was analyzed and *** factors that determined the system output were analyzed.A correctional system output approach was proposed to correct the influence of these factors,and to obtain the solar irradiance profile based on the measurements outputted by this *** overall performance of the system was examined in two ice floes in the Arctic during the 9th Chinese national Arctic research *** measured solar irradiance profiles were in good agreement with those obtained using other commercially available oceanographic *** derived apparent optical properties of sea ice were comparable to those of similar sea ice measured by other optical instruments.

关键词： solar irradiance profile sea ice fiber optic spectrometry inclined hole

Establishment and application of an intelligent treating method for oil spill identification

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2018年第11期37卷 116-122页

作者： TAN Liju ZHAO Ruxiang YIN Xiaonan ZHANG Haijiang WANG Jiangtao College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China Yantai Oil Spill Response Technical Center of Yantai Maritime Safety Administration Yantai 264000China

In the identifying process of an oil spill accident, manual integral and artificial visual comparison are commonly used at present to determine the oil spill sources, these methods are time-consuming and easily affected by human factors. Therefore, it is difficult to achieve the purpose of rapid identification of an oil spill accident. In this paper, an intelligent method of automatic recognition, integration and calculation of diagnostic ratio of Gas Chromatography-Mass Spectrometer （GC/MS） spectrum are established. Firstly, four hundreds of samples collected around the world were analyzed using a standard method and Retention time locking technology （RTL） was applied to reduce the change of retention time of GC/MS spectrum. Secondly, the automatic identification, integration of n-alkanes, biomarker compounds, polycyclic aromatic hydrocarbons and calculation of the diagnostic ratios were realized by MATLAB software. Finally, a database of oil fingerprints were established and applied successfully in a spill oil accident. Based on the new method and database, we could acquire the diagnostic ratios of an oil sample and find out the suspected oil within a few minutes. This method and database can improve the efficiency in spilled oil identification.

关键词： oil fingerprint automatic identification diagnostic ratio standardized database oil spills sources

Characteristics and influencing factors of frontal upwelling in the Yellow Sea in summer

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2022年第7期41卷 84-96页

作者： Fan Sun Fei Yu Guangcheng Si Jianfeng Wang Anqi Xu Jun Pan Ying Tang Institute of Oceanology Chinese Academy of SciencesQingdao266071China Tianjin Navigation Instruments research Institute Tianjin300131China University of Chinese Academy of Sciences Beijing100049China key Laboratory of Ocean Circulation and Waves Chinese Academy of SciencesQingdao266071China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao266071China Laboratory for Ocean Dynamics and Climate Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao266237China Center for Marine Environmental Engineering Institute of OceanologyChinese Academy of SciencesQingdao266071China

Frontal upwelling is an important phenomenon in summer in the Yellow Sea(YS)and plays an essential role in the distribution of nutrients and biological *** this paper,a three-dimensional hydrodynamic model is applied to investigate the characteristics and influencing factors of frontal upwelling in the *** results show that the strength and distribution of frontal upwelling are largely dependent on the topography and bottom temperature *** frontal upwelling in the YS is stronger and narrower near the eastern coast than near the western coast due to the steeper shelf ***,external forcings,such as the meridional wind speed and air temperature in summer and the air temperature in the preceding winter and spring,have certain influences on the strength of frontal *** increase in air temperature in the previous winter and spring weakens the frontal upwelling in summer;in contrast,an increase in air temperature in summer strengthens the frontal *** the southerly wind in summer increases,the upwelling intensifies in the western YS and weakens in the eastern *** air temperature influences the strength of upwelling by changing the baroclinicity in the frontal ***,the meridional wind speed in summer affects frontal upwelling via Ekman pumping.

关键词： influencing factors Yellow Sea frontal upwelling bottom temperature fronts numerical study

Short-term variations and influencing factors of suspended sediment concentrations at the Heisha Beach,Guangdong,China

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2022年第5期41卷 51-63页

作者： Jintang Ou Haoyan Dong Liangwen Jia Xiangxin Luo Zixiao He Kanglin Chen Jing Liu Yitong Lin Mingdong Yu Mingen Liang School of Marine Engineering and Technology Sun Yat-sen UniversityGuangzhou510275China School of Marine Sciences Sun Yat-sen UniversityGuangzhou510275China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519080China Guangdong Provincial Engineering research Center of Coasts Islands and ReefsGuangzhou510275China Institute of Estuarine and Coastal research School of Marine Engineering and TechnologySun Yat-sen UniversityGuangzhou510275China

Knowledge of sediment variation processes is essential to understand the evolution mechanism of beach morphology ***,a field measurement was conducted at the Heisha Beach,located on the west coast of the Zhujiang River(Pearl River)Estuary,to investigate the short-term variation in suspended sediment concentrations(SSCs)and the relationship between the SSC and turbulent kinetic energy,bottom shear stress(BSS),and relative wave *** on extreme event analysis results,extreme events have a greater influence on turbulent kinetic energy than *** a portion of the turbulent kinetic energy dissipates directly into the water column,it plays an important role in suspended sediment *** of the time,the wave-current interaction is strong enough to drive sediment incipience and *** combined,the wave-current interaction and wave-induced BSSs have a greater influence on suspended sediment transport and SSC variation than current-induced BSS *** relative wave height also has a strong correlation with SSC,indicating that the combined effect of water depth and wave height significantly impacts SSC *** depth is mainly controlled by the tide on the beaches;thus,the effects of tides and waves should be conjunctively considered when analyzing the factors influencing SSC.

关键词： Heisha Beach suspended sediment concentration variation turbulent kinetic energy bottom shear stress relative wave height

An evaluation of sea surface height assimilation using along-track and gridded products based on the Regional Ocean Modeling System(ROMS) and the four-dimensional variational data assimilation

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2018年第9期37卷 50-58页

作者： ZHOU Chaojie DING Xiaohua ZHANG Jie YANG Jungang MA Qiang Department of Mathematics Harbin Institute of Technology at Weihai The First Institute of Oceanography State Oceanic Administration

Remote sensing products are significant in the data assimilation of an ocean model. Considering the resolution and space coverage of different remote sensing data, two types of sea surface height（SSH） product are employed in the assimilation, including the gridded products from AVISO and the original along-track observations used in the generation. To explore their impact on the assimilation results, an experiment focus on the South China Sea（SCS） is conducted based on the Regional Ocean Modeling System（ROMS） and the four-dimensional variational data assimilation（4 DVAR） technology. The comparison with EN4 data set and Argo profile indicates that, the along-track SSH assimilation result presents to be more accurate than the gridded SSH assimilation, because some noises may have been introduced in the merging process. Moreover, the mesoscale eddy detection capability of the assimilation results is analyzed by a vector geometry–based algorithm. It is verified that, the assimilation of the gridded SSH shows superiority in describing the eddy＇s characteristics, since the complete structure of the ocean surface has been reconstructed by the original data merging.

关键词： ROMS 4DVAR sea surface height assimilation along-track gridded product

A novel algorithm for ocean wave direction inversion from X-band radar images based on optical flow method

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2018年第3期37卷 88-93页

作者： WANG Li CHENG Yunfei HONG Lijuan LIU Xinyu Third research Institute Ministry of Public Security

As one of the important sea state parameters for navigation safety and coastal resource management, the ocean wave direction represents the propagation direction of the wave. A novel algorithm based on an optical flow method is developed for the ocean wave direction inversion of the ocean wave fields imaged by the X-band radar continuously. The proposed algorithm utilizes the echo images received by the X-band wave monitoring radar to estimate the optical flow motion, and then the actual wave propagation direction can be obtained by taking a weighted average of the motion vector for each pixel. Compared with the traditional ocean wave direction inversion method based on frequency-domain, the novel algorithm is fully using a time-domain signal processing method without determination of a current velocity and a modulation transfer function（MTF）. In the meantime,the novel algorithm is simple, efficient and there is no need to do something more complicated here. Compared with traditional ocean wave direction inversion method, the ocean wave direction of derived by using this proposed method matches well with that measured by an in situ buoy nearby and the simulation data. These promising results demonstrate the efficiency and accuracy of the algorithm proposed in the paper.

关键词： X-band radar optical flow weighted average ocean wave direction radar image

SST diurnal warming in the China seas and northwestern Pacific Ocean using MTSAT satellite observations

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2016年第12期35卷 12-18页

作者： TU Qianguang PAN Delu HAO Zengzhou YAN Yunwei State key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyState Oceanic Administration Department of Earth Science Zhejiang University College of Geomatics and Municipal Engineering Zhejiang University of Water Resources and Electric Power

Hourly sea surface temperature(SST) observations from the geostationary satellite are increasingly used in studies of the diurnal warming of the surface oceans. The aim of this study is to derive the spatial and temporal distribution of diurnal warming in the China seas and northwestern Pacific Ocean from Multi-functional Transport Satellite(MTSAT) SST. The MTSAT SST is validated against drifting buoy measurements firstly. It shows mean biases is about –0.2°C and standard deviation is about 0.6°C comparable to other satellite SST accuracy. The results show that the tropics, mid-latitudes controlled by subtropical high and marginal seas are frequently affected by large diurnal warming. The Kuroshio and its extension regions are smaller compared with the surrounding regions. A clear seasonal signal, peaking at spring and summer can be seen from the long time series of diurnal warming in the domain in average. It may due to large insolation and low wind speed in spring and summer, while the winter being the opposite. Surface wind speed modulates the amplitude of the diurnal cycle by influencing the surface heat flux and by determining the momentum flux. For the shallow marginal seas, such as the East China Sea, turbidity would be another important factor promoting diurnal warming. It suggests the need for the diurnal variation to be considered in SST measurement, air-sea flux estimation and multiple sensors SST blending.

关键词： diurnal warming sea surface temperature remote sensing MTSAT

Wind speed inversion and in-orbit assessment of the imaging altimeter on Tiangong-2 space station

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2020年第12期39卷 114-120页

作者： Youguang Zhang Qingliu Bao Mingsen Lin Shuyan Lang key Laboratory of Space Ocean Remote Sensing and Application National Satellite Ocean Application ServiceBeijing 100081China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China Beijing Piesat Information Technology Co. Ltd.Beijing 100195China

Imaging altimeter(IALT)is a new type of radar altimeter *** contrast to the conventional nadir-looking altimeters,such as HY-2 A altimeter,Jason-1/2,and TOPEX/Poseidon,IALT observes the earth surface at low incident angles(2.5°–8°),so its swath is much wider and its spatial resolution is much higher than the previous *** paper presents a wind speed inversion method for the recently launched IALT onboard Tiangong-2 space *** the current calibration results of IALT do not agree well with the well-known wind geophysical model function at low incidence angles,a neural network is used to retrieve the ocean surface wind speed in this *** wind speed inversion accuracy is evaluated by comparing with the ECMWF reanalysis wind speed,buoy wind speed,and in-situ ship *** results show that the retrieved wind speed bias is about–0.21 m/s,and the root-mean-square(RMS)error is about 1.85 m/*** wind speed accuracy of IALT meets the performance requirement.

关键词： imaging altimeter ocean surface wind speed inversion accuracy analysis in-orbit assessment