Spectral similarity algorithm-based image classification for oil spill mapping of hyperspectral datasets

2020 ◽  
Author(s):  
Deepthi ◽  
Tessamma Thomas
Keyword(s):  
Oil Spill ◽  
Bohai Sea ◽  
Sea Water ◽  
Hybrid Algorithms ◽  
Chi Square ◽  
Spectral Similarity ◽  
Spectral Discrimination ◽  
Similarity Algorithm ◽  
Hyperion Image ◽  
Better Than

In remote sensing, the compositional information of part of the earth’s surface is statistically evaluated by comparing known field or library spectra with the unknown image spectra, known as spectral matching or spectral similarity analysis. In this research, hybrid spectral similarity algorithms developed based on chi-square distance (CHI or χ2) are used to retrieve useful information from the Hyperion hyperspectral oil spill image covering the area near Liaodong Bay of the Bohai Sea, China. In order to evaluate the discriminability of spectral similarity algorithms, a pixel-level matching is carried out between the reference vectors, viz. Oil Slick (O), Sheen (H), Sea Water (S) and Ship Track (T), collected visually from known areas in the image. The hybrid spectral similarity algorithms are statistically assessed for their performance using the spectral discriminatory measures (i) relative spectral discriminatory power (RSDPW), (ii) relative spectral discriminatory probability (RSDPB) and (iii) relative spectral discriminatory entropy (RSDE). Additionally, the selected hybrid algorithms are used on the Hyperion image subset to perform a pixel-based classification. Classification results revealed that the CHI-based hybrid algorithms performed better than all other hybrid spectral similarity methods. Therefore, the CHI-based hybrid algorithms demonstrated their superior spectral discrimination capacity to classify marine spectral classes for oil spill mapping from the hyperspectral dataset.

scholarly journals Marine Oil Slick Detection Based on Multi-Polarimetric Features Matching Method Using Polarimetric Synthetic Aperture Radar Data

Sensors ◽  
2019 ◽  
Vol 19 (23) ◽  
pp. 5176
Author(s):  
Guannan Li ◽  
Ying Li ◽  
Bingxin Liu ◽  
Peng Wu ◽  
Chen Chen
Keyword(s):  
Computational Complexity ◽  
Synthetic Aperture Radar ◽  
Oil Spill ◽  
Similarity Measures ◽  
Synthetic Aperture ◽  
Matching Method ◽  
Polarimetric Synthetic Aperture Radar ◽  
Spectral Similarity ◽  
Oil Spill Detection ◽  
Aperture Radar

Polarimetric synthetic aperture radar is an important tool in the effective detection of marine oil spills. In this study, two cases of Radarsat-2 Fine mode quad-polarimetric synthetic aperture radar datasets are exploited to detect a well-known oil seep area that collected over the Gulf of Mexico using the same research area, sensor, and time. A novel oil spill detection scheme based on a multi-polarimetric features model matching method using spectral pan-similarity measure (SPM) is proposed. A multi-polarimetric features curve is generated based on optimal polarimetric features selected using Jeffreys–Matusita distance considering its ability to discriminate between thick and thin oil slicks and seawater. The SPM is used to search for and match homogeneous unlabeled pixels and assign them to a class with the highest similarity to their spectral vector size, spectral curve shape, and spectral information content. The superiority of the SPM for oil spill detection compared to traditional spectral similarity measures is demonstrated for the first time based on accuracy assessments and computational complexity analysis by comparing with four traditional spectral similarity measures, random forest (RF), support vector machine (SVM), and decision tree (DT). Experiment results indicate that the proposed method has better oil spill detection capability, with a higher average accuracy and kappa coefficient (1.5–7.9% and 1–25% higher, respectively) than the four traditional spectral similarity measures under the same computational complexity operations. Furthermore, in most cases, the proposed method produces valuable and acceptable results that are better than the RF, SVM, and DT in terms of accuracy and computational complexity.

scholarly journals Application of asymmetric dicationic ionic liquids for oil spill remediation in sea water

2021 ◽  
Vol 14 (5) ◽  
pp. 103123
Author(s):  
C.E. El shafiee ◽  
R.A. El-Nagar ◽  
M.I. Nessim ◽  
M.M.H. Khalil ◽  
M.E. Shaban ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Oil Spill ◽  
Sea Water ◽  
Dicationic Ionic Liquids ◽  
Oil Spill Remediation

Introducing Problem-based Learning to Special Needs Dentistry—A Case Study

2002 ◽  
Vol os9 (1) ◽  
pp. 9-13 ◽  
Author(s):  
Raman Bedi ◽  
Jackie A Champion ◽  
Roger Davies
Keyword(s):  
Special Needs ◽  
Problem Based Learning ◽  
Chi Square ◽  
Training And Education ◽  
Mixed Response ◽  
Conventional Teaching ◽  
The Subject ◽  
Better Than ◽  
Made In

Introduction In order to promote training and education in special-needs dentistry an attempt was made to introduce problem-based learning (PBL) as a method of postgraduate dental education. The aim of this paper was to review the principles of PBL and report on a case study using this methodology. Method The case study was of a PBL session, on the subject of ‘problems of obtaining appropriate dental care for people with epilepsy’, undertaken at a national conference. Delegates were asked to complete a pre- and post-session questionnaire on PBL and their attitudes to the session. Results The session received a mixed response. Only 33 (35%) thought the session was valuable and only 20 (31%) thought it was better than conventional teaching methods and yet over half (55%) said they would like to attend more PBL in special-needs dentistry. Professionals complementary to dentistry were more likely to find the PBL session of value and to prefer the method to a more conventional format than dentists were (chi-square=5.5, df=1, p<0.05 and chi-square=5.9, df=1, p<0.05 respectively). Conclusion Valuable feedback was received from delegates. This will enable improvements to be made in future courses so that the effectiveness of PBL can be optimised.

The Risk Probability Analysis of Oil Spill on Offshore Facilities Based on ETA

2013 ◽  
Vol 864-867 ◽  
pp. 809-814
Author(s):  
Yun Bin Li ◽  
Cheng Gang Tang ◽  
Xian Feng Wang ◽  
Peng Xu
Keyword(s):  
Oil Spill ◽  
Bohai Sea ◽  
Marine Pollution ◽  
Probability Model ◽  
Pollution Prevention ◽  
The Bohai Sea ◽  
The Core ◽  
Eta Model ◽  
Subsea Pipelines ◽  
Core Problem

The oil spill probability is the core problem on studying the risk of oil spill. The oil spill probability model of offshore facilities is established, which based on the ETA model and the oil spill reason analysis of offshore facilities and subsea pipelines. Through a lot of statistics, combined with the actual situation in the Bohai Sea, the probability of various events is calculated. Finally the probability of oil spill for the Bohai Sea oil facilities and subsea pipelines is calculated and providing references for marine pollution prevention and the study of oil spill risks.

Application of magnetic separation for oil spill remediation and recovery in Kuwait sea water

2021 ◽  
Vol 209 ◽  
pp. 114-120
Author(s):  
Rana Malhas ◽  
Yaqoub Al-Ibrahim ◽  
Abdullah Al-Meraj ◽  
Hanan Abdullah ◽  
Abdulaziz Alshatti
Keyword(s):  
Magnetic Separation ◽  
Oil Spill ◽  
Sea Water ◽  
Oil Spill Remediation

The Effects of Recombinant Human Granulocyte–Macrophage Colony-Stimulating Factor Gel on Third-Degree Frostbite Wounds in Northeastern China: A Randomized Controlled Trial

2020 ◽  
Author(s):  
Xiu-Hang Zhang ◽  
Chang-Lei Cui ◽  
Hao-Yue Zhu ◽  
Jian Wang ◽  
Yan Xue ◽  
...  
Keyword(s):  
Bacterial Culture ◽  
Controlled Trial ◽  
Healing Time ◽  
Control Group ◽  
Fisher Exact Test ◽  
Chi Square ◽  
Exact Test ◽  
Positive Effects ◽  
Positive Bacterial Culture ◽  
Better Than

Abstract The aim of the study was to investigate the effects of the rhGM-CSF gel on third-degree frostbite wounds. Sixty-two patients who had suffered third-degree frostbite on their hand or foot (91 wounds in total) were selected using a convenience sampling method and randomly allocated to two groups: the rhGM-CSF group(31patients,45 frostbite wounds) received the rhGM-CSF gel when wound dressing change daily; however, the control group (31patients, 46 frostbite wounds) received aloe glue. The wound healing time, the score of inflammation about the wound and the positive bacterial culture of wound secretions were used to measure outcomes, respectively. Data were analyzed using SPSS (25.0), Student’s t test or Mann–Whitney U test and chi-square test or Fisher exact test were selected, as appropriate. The healing time of the rhGM-CSF group was (12.2 ± 5.0) days, which was significantly shorter than that of the control group (15.5 ± 4.7) days (P &lt; .0001). The rhGM-CSF group’s wound inflammation scores on the 7th and 14th day of treatment were (0.96 ± 0.21) and (1.88 ± 0.29), respectively, which were better than those of the control group (1.12 ± 0.24) and (1.38 ± 0.15) (both P &lt; .0001). The positive bacterial culture of wound secretions in the rhGM-CSF group was also better than that in the control group on the 3rd, 7th, and 14th day after treatment (P = .027, .004, .030, respectively). According to the results, using rhGM-CSF gel considerably increases the speed of frostbite wounds healing, and have an effect on protecting third-degree frostbite wounds regarding the positive effects. Trial Registration: This trial was registered in the Chinese Clinical Trial Register, ChiCTR1900021299.

Sign in / Sign up

Export Citation Format

Share Document