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Journal articles on the topic 'Ocean synoptic feature extraction'

Author: Grafiati

Published: 6 September 2023

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1

Chen, Xi, Shaojie Sun, Jun Zhao, and Bin Ai. "Spectral Discrimination of Pumice Rafts in Optical MSI Imagery." Remote Sensing 14, no. 22 (2022): 5854. http://dx.doi.org/10.3390/rs14225854.

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Pumice rafts are considered to be a long-range drifting agent that promotes material exchange and the dispersal of marine species. Large ones can also interfere with vessel navigation and have a negative impact on the social economy and marine ecosystems. Synoptic observations from the Multispectral Instrument (MSI) on-board Sentinel-2, with a spatial resolution of up to 10 m, provide an excellent means to monitor and track pumice rafts. In this study, the use of a Spectral-Feature-Based Extraction (SFBE) algorithm to automatically discriminate and extract pumice on the ocean surface from subm

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Shaji, C., and A. Gangopadhyay. "Synoptic Modeling in the Eastern Arabian Sea during the Southwest Monsoon Using Upwelling Feature Models." Journal of Atmospheric and Oceanic Technology 24, no. 5 (2007): 877–93. http://dx.doi.org/10.1175/jtech1984.1.

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Abstract Hydrographic observations along the western coast of India during the southwest (SW) monsoon season reveal upwelling in the equatorward surface flow and downwelling below the thermocline with a weak poleward undercurrent. Observations made previously during the peak of the SW monsoon in boreal summer showed that upwelling temperatures are much cooler (&lt;23°C) than compared to the available climatology data in this region. A feature modeling technique is used to describe the temperature distribution associated with the West India Coastal Current (WICC) upwelling. This kind of for

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Ma, Hualin, and Liyan Zhang. "Ocean SAR Image Segmentation and Edge Gradient Feature Extraction." Journal of Coastal Research 94, sp1 (2019): 141. http://dx.doi.org/10.2112/si94-028.1.

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Wang, Xiong Liang, and Chun Ling Wang. "Extraction of Ocean Fronts Based on Empirical Mode Decomposition." Applied Mechanics and Materials 701-702 (December 2014): 303–7. http://dx.doi.org/10.4028/www.scientific.net/amm.701-702.303.

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Ocean front is a narrow transitional zone that the penetration of sea is obviously different between two or more waters there. It is an important feature of geophysical turbulence which plays an important role in ocean dynamics. Ocean fronts become visible on radar images because they are associated with a variable surface current which modulates the sea surface roughness and thus the backscattered radar power. This paper propose a new integrated method to extract ocean fronts based on two-dimensional Empirical Mode Decomposition (EMD), image edge detection and mathematical morphology processi

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Ibebuchi, Chibuike Chiedozie, and Itohan-Osa Abu. "Relationship between synoptic circulations and the spatial distributions of rainfall in Zimbabwe." AIMS Geosciences 9, no. 1 (2022): 1–15. http://dx.doi.org/10.3934/geosci.2023001.

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<abstract> <p>This study examines how the atmospheric circulation patterns in Africa south of the equator govern the spatial distribution of precipitation in Zimbabwe. The moisture circulation patterns are designated by an ample set of eight classified circulation types (CTs). Here it is shown that all wet CTs over Zimbabwe features enhanced cyclonic/convective activity in the southwest Indian Ocean. Therefore, enhanced moisture availability in the southwest Indian Ocean is necessary for rainfall formation in parts of Zimbabwe. The wettest CT in Zimbabwe is characterized by a ridgi

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Dai, Panxi, and Ji Nie. "A Global Quasigeostrophic Diagnosis of Extratropical Extreme Precipitation." Journal of Climate 33, no. 22 (2020): 9629–42. http://dx.doi.org/10.1175/jcli-d-20-0146.1.

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AbstractThis paper presents a global picture of the dynamic processes and synoptic characteristics of extratropical extreme precipitation events (EPEs), defined as annual maximum daily precipitation averaged over 7.5° × 7.5° regional boxes. Based on the quasigeostrophic omega equation, extreme precipitation can be decomposed into components forced by large-scale adiabatic disturbances and amplified by diabatic heating feedback. The spatial distribution of the diabatic feedback parameter is largely controlled by atmospheric precipitable water and captured by a simple model. Most spatial heterog

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Jinkerson, Richard A., Stephen L. Abrams, Leonidas Bardis, et al. "Inspection and Feature Extraction of Marine Propellers." Journal of Ship Production 9, no. 02 (1993): 88–106. http://dx.doi.org/10.5957/jsp.1993.9.2.88.

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Localization is the process of determining the rigid-body translations and rotations that must be performed on the set of points measured on a manufactured surface to move those points into closest correspondence with the ideal design surface. In unconstrained localization all points have equal effect on the determination of the rigid-body transformation, while constrained localization allows a subset of the points to have stronger influence on the transformation. The measured points are physical points in space obtained by direct measurement of a manufactured marine propeller blade. The ideal

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Spensberger, Clemens, and Thomas Spengler. "Feature-Based Jet Variability in the Upper Troposphere." Journal of Climate 33, no. 16 (2020): 6849–71. http://dx.doi.org/10.1175/jcli-d-19-0715.1.

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AbstractJets in the upper troposphere constitute a cornerstone of both synoptic meteorology and climate dynamics, providing a direct link between weather and midlatitude climate variability. Conventionally, jet variability is often inferred indirectly through the variability of geopotential or sea level pressure. As recent findings pointed to physical discrepancies of this interpretation for the Southern Hemisphere, this study presents a global overview of jet variability based on automated jet detections in the upper troposphere. Consistent with previous studies, most ocean basins are dominat

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MATSUOKA, Daisuke, Fumiaki ARAKI, Shinichiro KIDA, Hideharu SASAKI, and Bunmei TAGUCHI. "J013024 Feature Extraction and Visualization of Ocean Currents via Cluster Analysis." Proceedings of Mechanical Engineering Congress, Japan 2013 (2013): _J013024–1—_J013024–3. http://dx.doi.org/10.1299/jsmemecj.2013._j013024-1.

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10

González-Alemán, Juan J., Francisco Valero, Francisco Martín-León, and Jenni L. Evans. "Classification and Synoptic Analysis of Subtropical Cyclones within the Northeastern Atlantic Ocean*." Journal of Climate 28, no. 8 (2015): 3331–52. http://dx.doi.org/10.1175/jcli-d-14-00276.1.

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Abstract Since more research is needed on subtropical cyclones (STCs) formed within the North Atlantic eastern basin, this survey analyzes them from a synoptic point of view, on a climatological basis, with the main aims of studying their common features, complementing other studies of these storms in the North Atlantic, and aiding the forecasting community. Fifteen cases of STCs were identified during the period 1979–2011 by applying a set of criteria from two databases. Composite analysis reveals that an extratropical depression acts as a precursor when it is isolated from the westerlies and

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Li, Xiukun, and Yushuang Wu. "Feature Extraction for Acoustic Scattering from a Buried Target." Journal of Marine Science and Application 18, no. 3 (2019): 380–86. http://dx.doi.org/10.1007/s11804-019-00102-9.

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Lin, Haixia, Jianhong Cui, and Xiangwei Bai. "Feature Extraction of Marine Water Pollution Based on Data Mining." Symmetry 13, no. 2 (2021): 355. http://dx.doi.org/10.3390/sym13020355.

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The ocean occupies more than two-thirds of the earth’s area, providing a lot of oxygen and materials for human survival and development. However, with human activities, a large number of sewage, plastic bags, and other wastes are discharged into the ocean, and the problem of marine water pollution has become a hot topic in the world. In order to extract the characteristics of marine water pollution, this study proposed K-means clustering technology based on cosine distance and discrimination to study the polluted water. In this study, the polygonal area method combined with six parameters of w

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Zhang, Hu, Lei Zhao, Quan Liu, et al. "An Improved Feature Extraction Method for Rolling Bearing Fault Diagnosis Based on MEMD and PE." Polish Maritime Research 25, s2 (2018): 98–106. http://dx.doi.org/10.2478/pomr-2018-0080.

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Abstract The health condition of rolling bearing can directly influence to the efficiency and lifecycle of rotating machinery, thus monitoring and diagnosing the faults of rolling bearing is of great importance. Unfortunately, vibration signals of rolling bearing are usually overwhelmed by external noise, so the fault frequencies of rolling bearing cannot be readily obtained. In this paper, an improved feature extraction method called IMFs_PE, which combines the multivariate empirical mode decomposition with the permutation entropy, is proposed to extract fault frequencies from the noisy beari

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Yutani, Taku, Oak Yono, Tatsu Kuwatani, et al. "Super-Resolution and Feature Extraction for Ocean Bathymetric Maps Using Sparse Coding." Sensors 22, no. 9 (2022): 3198. http://dx.doi.org/10.3390/s22093198.

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The comprehensive production of detailed bathymetric maps is important for disaster prevention, resource exploration, safe navigation, marine salvage, and monitoring of marine organisms. However, owing to observation difficulties, the amount of data on the world’s seabed topography is scarce. Therefore, it is essential to develop methods that effectively use the limited data. In this study, based on dictionary learning and sparse coding, we modified the super-resolution technique and applied it to seafloor topographical maps. Improving on the conventional method, before dictionary learning, we

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Gabruseva, Tatiana, Sergey Zlobin, and Peter Wang. "Photometric Light Curves Classification with Machine Learning." Journal of Astronomical Instrumentation 09, no. 01 (2020): 2050005. http://dx.doi.org/10.1142/s2251171720500051.

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The Large Synoptic Survey Telescope will begin its survey in 2022 and produce terabytes of imaging data each night. To work with this massive onset of data, automated algorithms to classify astronomical light curves are crucial. Here, we present a method for automated classification of photometric light curves for a range of astronomical objects. Our approach is based on the gradient boosting of decision trees, feature extraction and selection, and augmentation. The solution was developed in the context of The Photometric LSST Astronomical Time Series Classification Challenge (PLAsTiCC) and ac

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Zare, Mehdi, and Nowrouz Mohammad Nouri. "Novel feature extraction of underwater targets by encoding hydro-acoustic signatures as image." Applied Ocean Research 138 (September 2023): 103627. http://dx.doi.org/10.1016/j.apor.2023.103627.

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17

Li, Yuxing, Yilan Lou, Lili Liang, and Shuai Zhang. "Research on Feature Extraction of Ship-Radiated Noise Based on Multiscale Fuzzy Dispersion Entropy." Journal of Marine Science and Engineering 11, no. 5 (2023): 997. http://dx.doi.org/10.3390/jmse11050997.

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In recent years, fuzzy dispersion entropy (FDE) has been proposed and used in the feature extraction of various types of signals. However, FDE can only analyze a signal from a single time scale during practical application and ignores some important information. In order to overcome this drawback, on the basis of FDE, this paper introduces the concept of multiscale process and proposes multiscale FDE (MFDE), based on which an MFDE-based feature extraction method for ship-radiated noise is proposed. The experimental results of the simulated signals show that MFDE can reflect the changes in sign

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Tu, Wanli, Shuncong Zhong, Atilla Incecik, and Xibin Fu. "Defect feature extraction of marine protective coatings by terahertz pulsed imaging." Ocean Engineering 155 (May 2018): 382–91. http://dx.doi.org/10.1016/j.oceaneng.2018.01.033.

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19

Juliano, Timothy W., and Zachary J. Lebo. "Linking large-scale circulation patterns to low-cloud properties." Atmospheric Chemistry and Physics 20, no. 12 (2020): 7125–38. http://dx.doi.org/10.5194/acp-20-7125-2020.

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Abstract. The North Pacific High (NPH) is a fundamental meteorological feature present during the boreal warm season. Marine boundary layer (MBL) clouds, which are persistent in this oceanic region, are influenced directly by the NPH. In this study, we combine 11 years of reanalysis and an unsupervised machine learning technique to examine the gamut of 850 hPa synoptic-scale circulation patterns. This approach reveals two distinguishable regimes – a dominant NPH setup and a land-falling cyclone – and in between a spectrum of large-scale patterns. We then use satellite retrievals to elucidate f

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Wu, S. Y., and A. K. Liu. "Towards an automated ocean feature detection, extraction and classification scheme for SAR imagery." International Journal of Remote Sensing 24, no. 5 (2003): 935–51. http://dx.doi.org/10.1080/01431160210144606.

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Xiao, Yang, Zhiguo Cao, Wen Zhuo, Liang Ye, and Lei Zhu. "mCLOUD: A Multiview Visual Feature Extraction Mechanism for Ground-Based Cloud Image Categorization." Journal of Atmospheric and Oceanic Technology 33, no. 4 (2016): 789–801. http://dx.doi.org/10.1175/jtech-d-15-0015.1.

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AbstractIn this paper, a novel Multiview CLOUD (mCLOUD) visual feature extraction mechanism is proposed for the task of categorizing clouds based on ground-based images. To completely characterize the different types of clouds, mCLOUD first extracts the raw visual descriptors from the views of texture, structure, and color simultaneously, in a densely sampled way—specifically, the scale invariant feature transform (SIFT), the census transform histogram (CENTRIST), and the statistical color features are extracted, respectively. To obtain a more descriptive cloud representation, the feature enco

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22

Kaufman, Zachary S., Nicole Feldl, Wilbert Weijer, and Milena Veneziani. "Causal Interactions between Southern Ocean Polynyas and High-Latitude Atmosphere–Ocean Variability." Journal of Climate 33, no. 11 (2020): 4891–905. http://dx.doi.org/10.1175/jcli-d-19-0525.1.

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AbstractWeddell Sea open-ocean polynyas have been observed to occasionally release heat from the deep ocean to the atmosphere, indicating that their sporadic appearances may be an important feature of high-latitude atmosphere–ocean variability. Yet, observations of the phenomenon are sparse and many standard-resolution models represent these features poorly, if at all. We use a fully coupled, synoptic-scale preindustrial control simulation of the Energy Exascale Earth System Model (E3SMv0-HR) to effectively simulate open-ocean polynyas and investigate their role in the climate system. Our appr

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Calbó, Josep, and Jeff Sabburg. "Feature Extraction from Whole-Sky Ground-Based Images for Cloud-Type Recognition." Journal of Atmospheric and Oceanic Technology 25, no. 1 (2008): 3–14. http://dx.doi.org/10.1175/2007jtecha959.1.

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Abstract Several features that can be extracted from digital images of the sky and that can be useful for cloud-type classification of such images are presented. Some features are statistical measurements of image texture, some are based on the Fourier transform of the image and, finally, others are computed from the image where cloudy pixels are distinguished from clear-sky pixels. The use of the most suitable features in an automatic classification algorithm is also shown and discussed. Both the features and the classifier are developed over images taken by two different camera devices, name

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Yang, Hong, Xiaodie Yang, and Guohui Li. "Dual feature extraction system for ship-radiated noise and its application extension." Ocean Engineering 285 (October 2023): 115352. http://dx.doi.org/10.1016/j.oceaneng.2023.115352.

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Li, Yuxing, Xiao Chen, and Jing Yu. "A Hybrid Energy Feature Extraction Approach for Ship-Radiated Noise Based on CEEMDAN Combined with Energy Difference and Energy Entropy." Processes 7, no. 2 (2019): 69. http://dx.doi.org/10.3390/pr7020069.

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Influenced by the complexity of ocean environmental noise and the time-varying of underwater acoustic channels, feature extraction of underwater acoustic signals has always been a difficult challenge. To solve this dilemma, this paper introduces a hybrid energy feature extraction approach for ship-radiated noise (S-RN) based on complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) combined with energy difference (ED) and energy entropy (EE). This approach, named CEEMDAN-ED-EE, has two main advantages: (i) compared with empirical mode decomposition (EMD) and ensemble EMD

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Patrikalakis, Nicholas M., and Leonidas Bardis. "Feature Extraction from B-Spline Marine Propeller Representations." Journal of Ship Research 36, no. 03 (1992): 233–47. http://dx.doi.org/10.5957/jsr.1992.36.3.233.

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This paper presents accurate algorithms for the extraction of gross geometrical features of marine propeller blades represented in terms of B-spline surfaces. These features have important hydrodynamic function and include specifically the camber surface, the section thickness function, pitch, rake, skew, chord length, maximum thickness, maximum camber of the section and leading edge. The approximation of the camber surface, on which most of the remaining features are based, is an intricate problem relying on an extension of the concept of a Brooks ribbon and requiring the solution of a comple

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Lomazzi, Marco, Dara Entekhabi, Joaquim G. Pinto, Giorgio Roth, and Roberto Rudari. "Synoptic Preconditions for Extreme Flooding during the Summer Asian Monsoon in the Mumbai Area." Journal of Hydrometeorology 15, no. 1 (2014): 229–42. http://dx.doi.org/10.1175/jhm-d-13-039.1.

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Abstract The summer monsoon season is an important hydrometeorological feature of the Indian subcontinent and it has significant socioeconomic impacts. This study is aimed at understanding the processes associated with the occurrence of catastrophic flood events. The study has two novel features that add to the existing body of knowledge about the South Asian monsoon: 1) it combines traditional hydrometeorological observations (rain gauge measurements) with unconventional data (media and state historical records of reported flooding) to produce value-added century-long time series of potential

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Situmorang, Boldson Herdianto. "Identification of Biometrics Using Fingerprint Minutiae Extraction Based on Crossing Number Method." Komputasi: Jurnal Ilmiah Ilmu Komputer dan Matematika 20, no. 1 (2022): 71–80. http://dx.doi.org/10.33751/komputasi.v20i1.6814.

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Biometrics based on fingerprint images is a self-recognition technique using fingerprint to represent a person's identity. Fingerprint is characteristic of someone's identity precisely and safely because there are no similarities and cannot be falsified. The purpose of this research is to develop a biometrics identification system based on fingerprint images by utilizing a cell phone camera for the acquisition of fingerprint images. This is based on its simplicity because almost everyone has a cell phone so that a person's identification system based on fingerprint can be used anytime and anyw

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Ye, Jing, Zhaoyu Yuan, Cheng Qian, and Xiaoqiong Li. "CAA-YOLO: Combined-Attention-Augmented YOLO for Infrared Ocean Ships Detection." Sensors 22, no. 10 (2022): 3782. http://dx.doi.org/10.3390/s22103782.

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Infrared ocean ships detection still faces great challenges due to the low signal-to-noise ratio and low spatial resolution resulting in a severe lack of texture details for small infrared targets, as well as the distribution of the extremely multiscale ships. In this paper, we propose a CAA-YOLO to alleviate the problems. In this study, to highlight and preserve features of small targets, we apply a high-resolution feature layer (P2) to better use shallow details and the location information. In order to suppress the shallow noise of the P2 layer and further enhance the feature extraction cap

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Ioana, Cornel, Andr Quinquis, and Yann Stephan. "Feature Extraction From Underwater Signals Using Time-Frequency Warping Operators." IEEE Journal of Oceanic Engineering 31, no. 3 (2006): 628–45. http://dx.doi.org/10.1109/joe.2006.875275.

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Ashcroft, Linden Claire, Alexandre Bernardes Pezza, and Ian Simmonds. "Cold Events over Southern Australia: Synoptic Climatology and Hemispheric Structure." Journal of Climate 22, no. 24 (2009): 6679–98. http://dx.doi.org/10.1175/2009jcli2997.1.

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Abstract Cold events (CEs) are an important feature of southern Australian weather. Unseasonably cold conditions can have a significant impact on Australia’s agricultural industry and other aspects of society. In this study the bottom 0.4% of maximum temperatures in Melbourne and Perth from the 1958–2006 period are defined as CEs, representing the large-scale patterns affecting most of extratropical Australia. Compiling 6-hourly progressions of the tracks of the cyclones and anticyclones that are geostrophically associated with CEs gives for the first time a detailed synoptic climatology over

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Kubicek, Bernice, Ananya Sen Gupta, and Ivars Kirsteins. "Statistical-based feature extraction and classification of active sonar data." Journal of the Acoustical Society of America 151, no. 4 (2022): A267—A268. http://dx.doi.org/10.1121/10.0011297.

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Sonar target recognition is difficult due to the potential nonlinear overlap within an acoustic color response due to various backscatter and clutter within the ocean. This talk presents initial results from using a statistical model of feature vectors in conjunction with machine learning classifiers. Canonical correlation analysis (CCA) seeks to find two linear combinations of data by maximizing the correlation between the linear combinations while maintaining unit variance. In this application, CCA is used as a feature extraction method before target classification of active sonar data exper

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Spondylidis, Spyros, Konstantinos Topouzelis, Dimitris Kavroudakis, and Michail Vaitis. "Mesoscale Ocean Feature Identification in the North Aegean Sea with the Use of Sentinel-3 Data." Journal of Marine Science and Engineering 8, no. 10 (2020): 740. http://dx.doi.org/10.3390/jmse8100740.

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The identification of oceanographic circulation related features is a valuable tool for environmental and fishery management authorities, commercial use and institutional research. Remote sensing techniques are suitable for detection, as in situ measurements are prohibitively costly, spatially sparse and infrequent. Still, these imagery applications require a certain level of technical and theoretical skill making them practically unreachable to the immediate beneficiaries. In this paper a new geospatial web service is proposed for providing daily data on mesoscale oceanic feature identificati

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Oliveira, António José, Bruno Miguel Ferreira, and Nuno Alexandre Cruz. "A Performance Analysis of Feature Extraction Algorithms for Acoustic Image-Based Underwater Navigation." Journal of Marine Science and Engineering 9, no. 4 (2021): 361. http://dx.doi.org/10.3390/jmse9040361.

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In underwater navigation, sonars are useful sensing devices for operation in confined or structured environments, enabling the detection and identification of underwater environmental features through the acquisition of acoustic images. Nonetheless, in these environments, several problems affect their performance, such as background noise and multiple secondary echoes. In recent years, research has been conducted regarding the application of feature extraction algorithms to underwater acoustic images, with the purpose of achieving a robust solution for the detection and matching of environment

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Song, Xiangzhou, Chunlin Ning, Yongliang Duan, et al. "Observed Extreme Air–Sea Heat Flux Variations during Three Tropical Cyclones in the Tropical Southeastern Indian Ocean." Journal of Climate 34, no. 9 (2021): 3683–705. http://dx.doi.org/10.1175/jcli-d-20-0170.1.

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AbstractSix-month buoy-based heat flux observations from the poorly sampled tropical southeastern Indian Ocean are examined to document the extremes during three tropical cyclones (TCs) from December 2018 to May 2019. The most striking feature at the mooring site (16.9°S, 115.2°E) during the TCs is the extensively suppressed diurnal cycle of the net surface flux (Qnet), with a mean daytime (nighttime) reduction of 470 (131) W m−2, a peak decrease at approximately noon of 695 W m−2 and an extreme drop during TC Riley of 800 W m−2. The mean surface cooling in the daytime is primarily contributed

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Zhang, Pengfei, Shun Liu, and Qin Xu. "Identifying Doppler Velocity Contamination Caused by Migrating Birds. Part I: Feature Extraction and Quantification." Journal of Atmospheric and Oceanic Technology 22, no. 8 (2005): 1105–13. http://dx.doi.org/10.1175/jtech1757.1.

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Abstract Radar echoes from migrating birds can severely contaminate Doppler velocity measurements. For meteorological applications, especially quantitative applications in radar data assimilation, it is necessary to remove bird-contaminated velocity scans by using an automated identification technique. Such a technique should be also useful for ornithologists in selecting bird echoes automatically from radar scans. This technique can be developed in two steps: (i) extract the main features of migrating-bird echoes from reflectivity and Doppler velocity images and find proper parameters to quan

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Wu, Ji, Peng Li, Yongxian Wang, Qiang Lan, Wenbin Xiao, and Zhenghua Wang. "VFR: The Underwater Acoustic Target Recognition Using Cross-Domain Pre-Training with FBank Fusion Features." Journal of Marine Science and Engineering 11, no. 2 (2023): 263. http://dx.doi.org/10.3390/jmse11020263.

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Underwater acoustic target recognition is a hot research area in acoustic signal processing. With the development of deep learning, feature extraction and neural network computation have become two major steps of recognition. Due to the complexity of the marine environment, traditional feature extraction cannot express the characteristics of the targets well. In this paper, we propose an underwater acoustic target recognition approach named VFR. VFR adopts a novel feature extraction method by fusing three-dimensional FBank features, and inputs the extracted features into a residual network, in

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Zhao, Di, Hongyan Xing, Haifeng Wang, Huaizhou Zhang, Xinyi Liang, and Haoqi Li. "Sea-Surface Small Target Detection Based on Four Features Extracted by FAST Algorithm." Journal of Marine Science and Engineering 11, no. 2 (2023): 339. http://dx.doi.org/10.3390/jmse11020339.

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On account of current algorithm and parameter design difficulties and low detection accuracy in feature extractions of small target detections in sea clutter environment, this paper proposes a correspondingly improved four feature extraction method by FAST. After the short-time Fourier transform is applied, a time–frequency distribution spectrogram of original data is generated. Candidate feature points (CFP) are first extracted by FAST algorithm, and then a four-feature extraction is implemented with FAST and DBSCAN combined. The feature distinction is enhanced through a feature optimization.

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Sonawane, Jitendra, Mukesh Patil, and Gajanan Birajdar. "A novel feature extraction and mapping using convolutional autoencoder for enhancement of Underwater image/video." ITM Web of Conferences 44 (2022): 03066. http://dx.doi.org/10.1051/itmconf/20224403066.

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Marine resources known to human are very limited and as 71% world is surrounded by ocean, we are yet to discover the many of the species and the enriched resources. Often the Underwater scenery collected are poorly illuminated, degraded, and distorted due to light propagation model underwater, water molecules and impurities as well. Counting on to these factors images/videos collected in underwater environment are in need of enhancement. We propose a method of utilizing convolution autoencoder, which can be able to collect the features of underwater images and enhanced image and then the featu

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Ferreira, David, John Marshall, and Brian Rose. "Climate Determinism Revisited: Multiple Equilibria in a Complex Climate Model." Journal of Climate 24, no. 4 (2011): 992–1012. http://dx.doi.org/10.1175/2010jcli3580.1.

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Abstract Multiple equilibria in a coupled ocean–atmosphere–sea ice general circulation model (GCM) of an aquaplanet with many degrees of freedom are studied. Three different stable states are found for exactly the same set of parameters and external forcings: a cold state in which a polar sea ice cap extends into the midlatitudes; a warm state, which is ice free; and a completely sea ice–covered “snowball” state. Although low-order energy balance models of the climate are known to exhibit intransitivity (i.e., more than one climate state for a given set of governing equations), the results rep

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Liu, Kaiyue, Qi Sun, Daming Sun, Lin Peng, Mengduo Yang, and Nizhuan Wang. "Underwater Target Detection Based on Improved YOLOv7." Journal of Marine Science and Engineering 11, no. 3 (2023): 677. http://dx.doi.org/10.3390/jmse11030677.

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Underwater target detection is a crucial aspect of ocean exploration. However, conventional underwater target detection methods face several challenges such as inaccurate feature extraction, slow detection speed, and lack of robustness in complex underwater environments. To address these limitations, this study proposes an improved YOLOv7 network (YOLOv7-AC) for underwater target detection. The proposed network utilizes an ACmixBlock module to replace the 3 × 3 convolution block in the E-ELAN structure, and incorporates jump connections and 1 × 1 convolution architecture between ACmixBlock mod

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Zare, Mehdi, and Nowrouz Mohammad Nouri. "A new analysis of flow noise outside the time-frequency representation using graph-based feature extraction." Ocean Engineering 266 (December 2022): 112700. http://dx.doi.org/10.1016/j.oceaneng.2022.112700.

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Lv, Tu, Zeyu Chen, Feng Yao, and Mingjun Zhang. "Fault feature extraction method based on optimized sparse decomposition algorithm for AUV with weak thruster fault." Ocean Engineering 233 (August 2021): 109013. http://dx.doi.org/10.1016/j.oceaneng.2021.109013.

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Chen, Xiaoying, Aiguo Song, Jianqing Li, Yimin Zhu, Xuejin Sun, and Hong Zeng. "Texture Feature Extraction Method for Ground Nephogram Based on Hilbert Spectrum of Bidimensional Empirical Mode Decomposition." Journal of Atmospheric and Oceanic Technology 31, no. 9 (2014): 1982–94. http://dx.doi.org/10.1175/jtech-d-13-00238.1.

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Abstract It is important to recognize the type of cloud for automatic observation by ground nephoscope. Although cloud shapes are protean, cloud textures are relatively stable and contain rich information. In this paper, a novel method is presented to extract the nephogram feature from the Hilbert spectrum of cloud images using bidimensional empirical mode decomposition (BEMD). Cloud images are first decomposed into several intrinsic mode functions (IMFs) of textural features through BEMD. The IMFs are converted from two- to one-dimensional format, and then the Hilbert–Huang transform is perfo

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Li, Yuxing, Bingzhao Tang, and Shangbin Jiao. "SO-slope entropy coupled with SVMD: A novel adaptive feature extraction method for ship-radiated noise." Ocean Engineering 280 (July 2023): 114677. http://dx.doi.org/10.1016/j.oceaneng.2023.114677.

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Deng, Tianmin, Xuhui Liu, and Li Wang. "Occluded Vehicle Detection via Multi-Scale Hybrid Attention Mechanism in the Road Scene." Electronics 11, no. 17 (2022): 2709. http://dx.doi.org/10.3390/electronics11172709.

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The obstruction of vehicles by surrounding vehicles, obstacles, etc. is a common phenomenon in the practical application of automatic driving. In view of the problem that the vehicle’s vision is affected by the occlusion, the vehicle feature information is incomplete, resulting in the low detection accuracy of the occlusion vehicle, and the occlusion vehicle detection method based on the multi-scale hybrid attention mechanism is proposed. The paper aims to fully excavate the advantages of multi-scale feature extraction, channel/space attention and other modules, and to design a multi-scale hyb

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Li, Yuxing, Bo Geng, and Shangbin Jiao. "Refined Composite Multi-Scale Reverse Weighted Permutation Entropy and Its Applications in Ship-Radiated Noise." Entropy 23, no. 4 (2021): 476. http://dx.doi.org/10.3390/e23040476.

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Ship-radiated noise is one of the important signal types under the complex ocean background, which can well reflect physical properties of ships. As one of the valid measures to characterize the complexity of ship-radiated noise, permutation entropy (PE) has the advantages of high efficiency and simple calculation. However, PE has the problems of missing amplitude information and single scale. To address the two drawbacks, refined composite multi-scale reverse weighted PE (RCMRWPE), as a novel measurement technology of describing the signal complexity, is put forward based on refined composite

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Li, Weijia, Xiaohong Shen, and Yaan Li. "A Comparative Study of Multiscale Sample Entropy and Hierarchical Entropy and Its Application in Feature Extraction for Ship-Radiated Noise." Entropy 21, no. 8 (2019): 793. http://dx.doi.org/10.3390/e21080793.

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The presence of marine ambient noise makes it difficult to extract effective features from ship-radiated noise. Traditional feature extraction methods based on the Fourier transform or wavelets are limited in such a complex ocean environment. Recently, entropy-based methods have been proven to have many advantages compared with traditional methods. In this paper, we propose a novel feature extraction method for ship-radiated noise based on hierarchical entropy (HE). Compared with the traditional entropy, namely multiscale sample entropy (MSE), which only considers information carried in the lo

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Randolph Ford, W., and Ingrid G. Farreras. "Using Human Intelligence to Test the Impact of Popular Preprocessing Steps and Feature Extraction in the Analysis of Human Language." International Journal of Data Science and Analysis 8, no. 1 (2022): 18. http://dx.doi.org/10.11648/j.ijdsa.20220801.13.

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Zhang, Dehuan, Wei Cao, Jingchun Zhou, Yan-Tsung Peng, Weishi Zhang, and Zifan Lin. "Two-Branch Underwater Image Enhancement and Original Resolution Information Optimization Strategy in Ocean Observation." Journal of Marine Science and Engineering 11, no. 7 (2023): 1285. http://dx.doi.org/10.3390/jmse11071285.

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In complex marine environments, underwater images often suffer from color distortion, blur, and poor visibility. Existing underwater image enhancement methods predominantly rely on the U-net structure, which assigns the same weight to different resolution information. However, this approach lacks the ability to extract sufficient detailed information, resulting in problems such as blurred details and color distortion. We propose a two-branch underwater image enhancement method with an optimized original resolution information strategy to address this limitation. Our method comprises a feature

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