bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative analysis of two impact systems in a snowstorm in Dalian
Authors: Sai Han , Li Yan , Liu Shuo , Geng Dan 
Published: June 2023

Abstract
In this study, the two influence systems in a snowstorm that occurred in January 2021 are analyzed using conventional observation, intensive snowfall observation data and NCEP-FNL 0.25°×0.25° analysis data. The results show that, first, the westerly trough combined with the surface convergence line and the sub cold front produces strong snowfall in the southern part of the Liaodong Peninsula, then the strong cold air moves southward into the cold flow snowfall. When the westerly trough system has a large water vapor flux, deep wet layer and strong ascending motion, the surface is accompanied by the obvious warm tongue in southwest Dalian and cold pad in the inland, and there is obvious frontogenesis process, with heavy snowfall. The intensity of cold advection is closely related to the amount of snowfall: the stronger the cold advections, the greater the snowfall will be. The combination of mid-upper-level divergence with negative vorticity and convergence with positive vorticity near the ground is also an advantage for heavy snowfall. Cold flow snowfall exhibits strong local characteristics. Compared with the westerly trough system, the cold flow snowfall has a smaller influence area and intensity. The combination of strong ascending motion and wet area is also one of the focuses of cold flow snowfall forecast in Dalian.
Scaled model testing for the helical strakes in reducing the vortex-induced vibrations
Authors: Sun Jiayao , Mo Shiqi , Ye Renchuan , Liu Hu 
Published: June 2023

Abstract
The accuracy of the prediction of the suppression efficiency of the triplex helical strakes for vortex-induced vibrations (VIV) is important in the offshore industry for the risers. Towing tank tests of the 1:1 section model have been used in the study of one degree of freedom; however, this method requires a long time for both the preparation and the testing. In this study, a scaled model testing method based on the flume and the oscillating frame is proposed, which measured the oscillating amplitude and the forces for both the bare pipe and the triplex helical strakes. The scaled tests were carried out in the TU Delft, with the range of Reynolds number between 6000 and 20000. The results were compared with the real model test applied in the towing tank to evaluate the accuracy. The measured strake efficiency of the scale model test agrees with the full-scale model test, providing support for the scaled model test in reducing the vortex-induced vibrations.
Experimental study of Stokes drift in combined wave-current flows using Particle Image Velocimetry
Authors: Zhang X , Zheng J H , Zhang C 
Published: June 2023

Abstract
In the present study, Eulerian velocities were obtained using the PIV system to investigate the problem of Stokes drift in combined wave-current flows. Time-averaged mean Eulerian velocity profiles were presented after the flow has achieved its equilibrium status. Waves with various wave periods and amplitudes were generated and propagated with the turbulent current possessing a Reynolds number of 32000. Results of the time-averaged mean velocity profiles suggest the absence of a return flow in an open flume. The discrepancies of the depth-averaged mean velocity with and without waves superimposed were found to be in good agreements with the return flow speeds as predicted by Kim (1984). This further confirmed the applicability of their solution for calculating the return flow under the condition of waves propagating with currents.
Inversion of Full-depth Temperature Profiles Based on Surface Temperature and AUV Measured Data
Authors: Xian Yan , Qianqian Li , Qian Tong , Ziwen Wang , Shoulian Cao , Zhichuan Ma 
Published: June 2023

Abstract
The sound speed profile has an important impact on sound propagation and underwater acoustic detection, and the water temperature has the most significant impact on the sound speed, so it is critical to obtain high-precision full-depth temperature profiles. With the rapid development of marine mobile platforms, it is possible to obtain depth-fixed temperature data using surface velocimeter or autonomous underwater vehicles (AUVs). This paper uses the measured thermistor chain data to carry out numerical simulation, and discusses the feasibility of reconstructed full-depth temperature profiles using measured temperature of few discrete depths. The back propagation (BP) neural network is used to generate the nonlinear mapping relationship between the temperature in a few discrete depths and the first two empirical orthogonal function (EOF) coefficients. The experimental results show that the temperature at two specially selected depths can reflect the full-depth temperature profiles to a certain extent. However, the information about the water temperature at different depths is diverse and the thermocline contains the most information. As the depth-fixed data measured by the AUV increases, the inversion accuracy of the full-depth temperature profiles increases accordingly. Results shows that, even in ocean regions that have solitary internal waves, when the depth of the depth-fixed data is selected the same as the depth of the surface layer and the two extreme points of the second EOF, the root mean square error (RMSE) of almost all reconstructed temperature profiles in the test set is less than 0.2°C, and the mean RMSE is about 0.12°C.
Correction of WindSat sea surface wind speed under rain
Authors: Jiang Zhuhui , Kong Xiaojuan , Ai Weihua , Du Xiaoyong , Ma Ming , Chen Jian , Chang Haotian , Jiang Chen , Zhang Wei 
Published: June 2023

Abstract
To improve the accuracy of sea surface wind speed under rain based on data obtained from the U.S. spaceborne fully polarimetric microwave radiometer (WindSat), a wind speed correction model based on a statistical algorithm is constructed. First, the coupled samples from 2003 to 2014 are considered as the training sample set, and the coupled samples from 2015 to 2020 are used as the test sample set. Then, the WindSat sea surface wind speed under rain correction model is constructed. Results show that the WindSat wind speed data is overestimated severely. The higher the wind speed, the larger the wind speed is overestimated. The experimental results reveal that the WindSat wind speed standard deviation of the test samples is 2.6 m/s. However, the wind speed standard deviation decreases to 2.2 m/s after correction.
Automatic Detection of Eddies Based on Remote Sensing SAR Images
Authors: Wang Yangjun , Bai Chenzu , Ma Ming , Zhang Shuo , Liu Hengchang 
Published: June 2023

Abstract
A series of problems such as climate change, population explosion and energy crisis make people have to focus on the development of new energy. The 21st Century Maritime Silk Road region, with its large population and well-developed industry, is well suited for the development of new energy, especially offshore wind energy resources. Aiming at the regionalization problem of offshore wind power stations in this region, this paper uses the analysis data of ERA5, GSHHS data, combined with authoritative geography humanities data, combined with subjective and objective comprehensive weighting method, and establishes a comprehensive risk assessment system which is different from previous ones. The results show that wind energy resources, natural environment and geography humanities factors have a certain impact on the location of offshore wind power stations in the 21st century Maritime Silk Road region. Therefore, it is meaningful and necessary to add these indicators into the location index system of offshore wind power stations in the 21st Century Maritime Silk Road region.
Sea Clutter Measurement Test and Amplitude Characteristics Analysis in the South China Sea Nearshore Area
Authors: Zhao X. , Han J. , Zhang X. , Zhang J. , Li P. 
Published: June 2023

Abstract
To address the problem of sea clutter amplitude distribution characteristics varying with bandwidth, this paper obtains the raw data of clutter under different polarization methods of HH and VV in X and Ka bands based on the sea clutter measurement experiment carried out in June 2022 in the near-shore waters of South China Sea. For the data in X-band HH polarization mode, the goodness-of-fit test was conducted based on the classical models of Rayleigh, Weibull, log-normal and K distribution for the amplitude distribution characteristics of the sea clutter, and the variation of the estimated parameters of the distribution model with the bandwidth was analyzed. The test data show that: 1, with the increase of bandwidth sea clutter amplitude decreases; 2, with the increase of bandwidth Weibull distribution model parameters are decreasing trend, k distribution parameters are increasing trend; 3, the test conditions, the offshore sea clutter amplitude distribution is the optimal K distribution. The conclusions of this paper can provide a comparison and reference for the subsequent study on the characteristics of sea clutter distribution.
Location of the 21st Century Maritime Silk Road Marine Wind Energy Site
Authors: Xu Jing , Zhang Ren , Wang Yangjun , Yan Hengqian , Liu Quanhong , Guo Yutong , Ren Yongcun 
Published: June 2023

Abstract
A series of problems such as climate change, population explosion and energy crisis make people have to focus on the development of new energy. The 21st Century Maritime Silk Road region, with its large population and well-developed industry, is well suited for the development of new energy, especially offshore wind energy resources. Aiming at the regionalization problem of offshore wind power stations in this region, this paper uses the analysis data of authoritative geography humanities data and establishes a comprehensive risk assessment system. The results show that wind energy resources, natural environment and geography humanities factors have a certain influence on the location of offshore wind power stations in the region. Also, they shows that different indicators have different results. Therefore, it is meaningful and necessary to add these indicators into the location indicator system of offshore wind power stations in the region.
Ocean data compression based on block SVD
Authors: Wang Yishuo , Zhou Muping , Zhou Feng 
Published: June 2023

Abstract
Fast development of ocean observations and numerical modeling increases the need for data transmission, storage and extraction. This paper presented a new data compression method based on Singular Value Decomposition (SVD) with data matrix divided into different sub-matrices with consideration of odevity and remnant. An automatic matrix-dividing method is applied to divide smartly the data matrix into sub-matrices. These sub-matrices are then compressed based on an improved SVD, which enhances the compression performance by utilizing the orthogonal property of vectors generated by SVD. A dynamic optimization method which is capable of determining the proper scale of retained data under the accuracy requirement of ocean data is also established. Two indices are derived mathematically to search the best block pattern quickly. The performance and reliability of the block-based SVD compression is verified with the successful compression and recovery of the Hybrid Coordinate Ocean Model data.
An Ensemble Kalman Filter Data Assimilation Method for the Sea Surface Temperature in the China Seas: Implementation and Simulation Experiments
Authors: Li Zhijie , Li Yun , Wang Zhaoyi , Zheng Jingjing 
Published: June 2023

Abstract
Data assimilation refers to a method of integrating observation data in the dynamic operation of numerical models on the basis of considering the temporal and spatial distribution of data and the error of observation field and background field. The Ensemble Kalman filter (EnKF) as a technology that has been widely used in the field of atmosphere and ocean has been applied to the ROMS (the Regional Ocean Modeling System) for predicting Sea surface temperature in Yellow, and East China Seas. In order to explore the applicability and effectiveness of the EnKF method for improving the accuracy of marine numerical model, the Sea surface temperature (SST) gained from buoy were used to conduct data assimilation process with EnKF method. Twin experiments have been performed to analysis the sensitivity of this system to the ensemble size and errors in model simulation and observations and a real data assimilation scheme has been conducted to hindcast the SST at the Yellow, and East China Seas during the July of year 2014. The updated results after data assimilation indicate that the model simulation fits observation better when the forecast was updated by observations. The result show that EnKF can effectively reduce the simulation error of complex numerical marine models.
Numerical Study on the Genesis of Incipient Vortex of a Tropical Storm over the South China Sea. Part II Sensitivity of Sea Surface Sensible Heating
Authors: Hao S , Liu X Y , Chen L , Liu K W 
Published: June 2023

Abstract
The experiments are conducted to determine the impact of the anomalous surface sensible heating (SH) from the South China Sea (SCS) on the incipient vortex of the storm Mindulle (2010) formation by using the Weather Research and Forecasting (WRF) model, including the control-run with and the sensitivity-run without such heating. Significant impact is seen, with the incipient vortex failing to generate without the related SH. Based on the atmospheric thermal adaption theory, the outputs reveal that the genesis of the incipient vortex can be divided into the formation stage and the strengthen stage. At the formation stage, the surface SH favoured the enhancement of the surface convergence. Thus strong westerlies and southerlies along with the topography forcing constrain updrafts over the Luzon Island. The non-uniform condensation latent heating (LH) released by the vertical motion creates the cyclonic vorticity in the lower atmosphere, which was conducive to the incipient vortex formation. At the strengthen stage, the more intense LH due to the enhanced ascending motions mainly contributed to cyclonic vorticity generation. Therefore, the incipient vortex continuously strengthened and attained to the intensity of tropical storm. The simulation results illustrate that the development of the Mindulle (2010) is a “bottom-up” process.
Improvements of ocean fronts forecasting in the South China Sea by using ensemble optimal interpolation assimilation
Authors: Ren S , Zu Z , Zhu X , Wang Y , Zhang Y 
Published: June 2023

Abstract
Based on the operational ocean forecasting system in the South China Sea (SCS) runned by National Marine Environmental Forecasting Center (NMEFC), current Ensemble Optimal Assimilation (EnOI) system are updated by developing the dynamic coordination of multi-source data assimilation system, and has carried on the systematic evaluation. The diagnostic analysis of ocean fronts in the SCS is carried out using the daily average hindcast results in 2018, and the improvement effect of data assimilation on ocean mesoscale processes was evaluated. The statistical analysis results show that the occurrence frequency and diagnostic parameters of the ocean front after assimilation are closer to the observation. The comparison of the scores of the ocean front prediction skills before and after assimilation shows that the assimilated model has higher front prediction skills.
The Long-term variability of Global Typical Oceanic Fronts
Authors: Liao Haolin , Zhang Yongchui 
Published: June 2023

Abstract
Using high-resolution NOAA Optimum Interpolation sea surface temperature (OISST) data, the temporal and spatial characteristics of typical oceanic fronts in the past 39 years, including Oyashio front, Gulf Stream front, Peru current front and southern Indian Ocean polar front, are analyzed. The results show that the intensities of the four typical fronts have all strengthened, among which the Peru current is the most significant and the South Indian Ocean polar front is the weakest. The movement of the fronts are quite different: the Oyashio front has a significant poleward movement, and the Gulf Stream front extending into the open sea part has a marginal poleward movement; while the south Indian Ocean polar front and Peru current front have no obvious movements.
Long-term thermohaline trends in the Sulawesi Sea based on a high-resolution reanalysis data
Authors: Li Aojie , Zhang Yongchui 
Published: June 2023

Abstract
Based on the global ocean reanalysis data of COPERNICUS MARINE ENVIRONMENT MONITORING SERVICE (CMEMS) from 1993 to 2019, the long-term thermohaline trends in the Sulawesi Sea are analyzed. The results show that the temperature of the upper middle layer of the Sulawesi Sea has a long-term increasing trend, and the fastest warming is located at 130m, which is 0.05°C/yr, implying a total of 1.35°C in the 27 years. For salinity, there is a whole negative trend, except for the surface layer. Further study shows that the temperature and salinity interannual variations show positive and negative correlation with Niño index, respectively.
Study on the Influence of Salt Marsh Vegetation on Tidal Current and Sediment Transport in Intertidal Zone
Authors: Chen M. Y. , Luo F. , Dai J. C. 
Published: June 2023

Abstract
Due to the sensitivity of the environment and immoderate human activities, the coastal zone in China is facing resource conflicts and environmental pressures. Salt marsh vegetation is regarded as an important measure for coastal ecological restoration. Therefore, it is of practical significance to study the influence of salt marsh vegetation on hydro-sediment dynamics. Based on the measured topography and tidal sediment data, a generalized model of salt marsh vegetation is established to study its effects on the dynamics of nearshore water and sediment. The results show that salt marsh vegetation has prominent effect of attenuating flow velocity and promoting sedimentation, and the ability differs depending on vegetation. Salt marsh vegetation can promote the development of tidal channels to shore, causing intensified erosion in the deep trough. The expansion of the vegetation area will allow the tidal channels to extend small branches to shore and connect with the vegetation front.
Simulation Study on Optimization Design of MEMS Hydrophone Based on AlN Film
Authors: Yu Qiankun , Zou Yongchao , Zhang Wen 
Published: June 2023

Abstract
In this paper, simulation study on optimization design of MEMS hydrophone based on AlN (Aluminum Nitride) film is carried out. Based on the theory of elastic mechanics and sound-solid coupling effect, the effect of film shape on the sensitivity and frequency response of the device is studied firstly. Results show that a square shape is beneficial to improving the overall performance of the device. The effects of piezoelectric film thickness and radius on the device performance are studied consequently. Results show that increasing the piezoelectric film radius significantly improves the device sensitivity. Finally, the effects of sandwiched and unequal-thickness piezoelectric structures on the device performance are investigated. It is found that unequal-thickness piezoelectric structures can remarkably improve the device performance. Results of this paper would support the performance improvement of MEMS hydrophones based on AlN film in future research work.
Design and Verification of Low Frequency Alternating Magnetic Field Detection Device Based on Unstable Platform
Authors: Zhao Zhe , Jiao Dawen , Hu Ping , Zhang Jing , Cui Pei , Lv Junjun 
Published: June 2023

Abstract
Low frequency alternating magnetic field is one of the important features for marine magnetic field detection. In order to realize the effective detection of low-frequency alternating magnetic field signal in the marine environment, a low-frequency alternating magnetic field detection device based on unstable platform was designed based on the low-power optical pump magnetometer and signal control processing circuit in this paper. The magnetic field signal can be stored. The power spectrum analysis, line spectrum purification, line spectrum extraction and so on can be processed online, and the processing results are saved and transmitted to the upper computer through serial communication. The test results of laboratory and offshore signal source show that the device has good ability of low frequency alternating magnetic field measurement, analysis and line spectrum extraction.
Design of Single-Polarized Single-mode Photonic Crystal Fiber Without Air Holes in the Cladding
Authors: Wang Weilong , Zhang Zejun , Liu Songjie , Wang Xiyin , Tsuji Yasuhide , Xu Jing 
Published: June 2023

Abstract
This study proposes a novel single-polarized single-mode (SPSM) photonic crystal fiber (PCF) without air holes in the cladding, and the silicon nitride holes and air holes in the core of the PCF are staggered. Based on the full vector finite element method, the birefringence characteristics with different hole sizes have been discussed in detail, and a SPSM-PCF is achieved through optimizing the core structure. Moreover, the extinction ratio, effective refractive index, dispersion, confinement loss and nonlinearity of the PCF are analyzed. Simulation results show that the PCF can obtain a high birefringence value of 2.142 × 10−3
, a large negative dispersion of −2750 ps/(nm · km), a low confinement loss of 1.57 × 10−7dB/m and a high nonlinear coefficient of 90.5W−1 · km−1
at the wavelength of 1.55 μm. In this paper, the proposed structure has the properties of high birefringence and high negative dispersion, which can be used in fiber laser, optical fiber sensing, dispersion compensation and other fields.
Scintillation Characteristics of Gaussian Vortex Beam Propagation in Turbulent Flume
Authors: Zhang L. , Wang Y. , Lin H. , Guo Y. , Jin F. 
Published: June 2023

Abstract
Aiming at the low sensitivity of weak turbulent wake detection of underwater vehicles, studied the laser propagation characteristics in underwater weak turbulence, and then proposed a method based on the statistical characteristics of the scintillation peak of Gaussian vortex beam for detecting the weak turbulence fluctuation. According to the refractive index power spectrum of turbulent flume, the intensity distribution images of Gaussian vortex beam propagating through turbulent flume are simulated by using the random phase screen method, and the scintillation characteristics of Gaussian vortex beam under different conditions are studied. For the simulation results, under the weak turbulence conditions with low refractive index structure coefficient, the average scintillation indexes near the peak value of spot scintillation indexes are obviously higher than those of the whole image. Under the condition that the temperature difference between hot plate and cold plate, between hot plate and water are about 6.4°C and 5.8°C, respectively, the scintillation indexes of the laser propagation intensity image under different temperature gradient (turbulence intensity) are calculated in the experiment. The results show that, the mean values of the scintillation indexes near the spot scintillation peak fluctuate around 1.02 and 1.07, and the mean values in whole image fluctuate around 0.58 and 0.68, respectively, when the temperature gradient is small, which verify the effectiveness of the statistical characteristics of the scintillation peak in detecting weak turbulence.