A novel framework of real-time regional collision risk prediction based on RNN approach

To reduce the risk of collision in territorial sea areas, including trade ports and entry waterways, and to enhance the safety and efficiency of ship passage, the International Maritime Organization requires the governing body of every country to establish and operate a vessel traffic service (VTS). However, previous studies on risk prediction models did not consider the locations of near collisions and actual collisions and only employed a combined collision risk index in surveillance sea areas. In this study, we propose a regional collision risk prediction system for a collision area considering spatial patterns using a density-based spatial clustering of applications with noise (DBSCAN). Furthermore, a fuzzy inference system based on a near collision (FIS-NC) and long short-term memory (LSTM) is adopted to help a vessel traffic service operator (VTSO) make timely optimal decisions. In the local spatial pattern stage, the ship trajectory was determined by identifying the actual-collision and near-collision locations simultaneously. Finally, the system was developed by learning a sequence dataset from the extracted trajectory of the ship when a collision occurred. The proposed system can recommend an action faster than the fuzzy inference system based on the near-collision location. Therefore, using the developed system, a VTSO can quickly predict ship collision risk situations and make timely optimal decisions at dangerous surveillance sea areas.

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A novel approach to real-time risk prediction for emerging infectious diseases: A case study in Avian Influenza H5N1

Preventive Veterinary Medicine ◽

10.1016/j.prevetmed.2009.05.019 ◽

2009 ◽

Vol 91 (1) ◽

pp. 19-28 ◽

Cited By ~ 28

Author(s):

C.P. Jewell ◽

T. Kypraios ◽

R.M. Christley ◽

G.O. Roberts

Keyword(s):

Avian Influenza ◽

Infectious Diseases ◽

Real Time ◽

Risk Prediction ◽

Emerging Infectious Diseases ◽

Novel Approach ◽

Avian Influenza H5n1 ◽

Influenza H5n1

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Successful Collision Risk Management with Realtime Advanced Survey Correction in A Challenging Horizontal Well

10.2523/iptc-21858-ms ◽

2021 ◽

Author(s):

Tongkum Tossapol ◽

Khamawat Siritheerasas ◽

Feras Abu Jafar ◽

Trinh Dinh Phu ◽

Pham Nam Hieu

Keyword(s):

Risk Management ◽

Real Time ◽

Separation Factor ◽

3D Visualization ◽

Management Technique ◽

Collision Risk ◽

Time Saving ◽

Complex Design ◽

Measurement While Drilling ◽

Difficulty Index

Abstract The Well X in Nong Yao field, is an infill-well designed for the Gulf of Thailand which presented several interesting challenges due to its complexity, tortuosity, and potential collision risks with other wells. This paper demonstrates the application of a Real-time Advanced Survey Correction (RASC) with Multi Station Analysis (MSA) to correct the Measurement While Drilling (MWD)'s azimuth. The Well X is a 3D Complex design with a high drilling difficulty index (DDI) at 6.9, high tortuosity of 316 degree, and which has an aggressive build on inclination and azimuthal U-turning well path. The well also creates difficult doglegs severity (DLS) up to 5.5deg/100ft, which is near the limit of the flexibility required to achieve the horizontal landing point. The conventional MWD survey, with proximity scanning with the nearby Well A, demonstrates high risk with a calculated Oriented Separation Factor (OSF) of 1.01. The RASC-MSA method is applied with a clearly defined workflow during execution in real-time and provide significant improvement in calculated OSF. RASC-MSA is applied for every 1,000 ft interval drilling below the 9.625in casing shoe. The workflow ensures that the directional driller follows the corrected survey along the well path and especially in the last 300 ft before reaching the electrical submersible pump (ESP) tangent section. The result from RASC-MSA, indicated a 29 ft lateral shift on the left side of the MWD standard surveys. Without this technique, Well X has a high potential to collide with Well A and Well B (Figure 1) as the actual OSF may less than 1 while drilling. The final 3D Least Distance proximity scanning with Well A shows a minimum OSF = 1.35, which is a 30% improvement compared to the conventional MWD survey. Another nearby well, Well B, indicates a minimum OSF=1.66 and passed the anti-collision OSF rule. In consideration of the drilling efficiency, availability, cost effectiveness and time saving, the RASC-MSA analysis to correct the MWD's azimuth are applied and the separation factor can be improved by 30%. In conclusion, the collision risk management technique applied successfully met the complex challenges of Well X, which was successfully drilled and safely delivered. Figure 1 3D visualization to exhibit the collision issue between Well X and nearby existing Wells A and Well B.

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