4 research outputs found
Real Field Deployment of a Smart Fiber Optic Surveillance System for Pipeline Integrity Threat Detection: Architectural Issues and Blind Field Test Results
This paper presents an on-line augmented surveillance
system that aims to real time monitoring of activities
along a pipeline. The system is deployed in a fully realistic
scenario and exposed to real activities carried out in unknown
places at unknown times within a given test time interval (socalled
blind field tests). We describe the system architecture that
includes specific modules to deal with the fact that continuous
on-line monitoring needs to be carried out, while addressing
the need of limiting the false alarms at reasonable rates. To
the best or our knowledge, this is the first published work in
which a pipeline integrity threat detection system is deployed
in a realistic scenario (using a fiber optic along an active gas
pipeline) and is thoroughly and objectively evaluated in realistic
blind conditions. The system integrates two operation modes:
The machine+activity identification mode identifies the machine
that is carrying out a certain activity along the pipeline, and the
threat detection mode directly identifies if the activity along the
pipeline is a threat or not. The blind field tests are carried out
in two different pipeline sections: The first section corresponds
to the case where the sensor is close to the sensed area, while
the second one places the sensed area about 35 km far from
the sensor. Results of the machine+activity identification mode
showed an average machine+activity classification rate of 46:6%.
For the threat detection mode, 8 out of 10 threats were correctly
detected, with only 1 false alarm appearing in a 55:5-hour sensed
period.European CommissionMinisterio de EconomĂa y CompetitividadComunidad de Madri
A Long Distance Phase-Sensitive Optical Time Domain Reflectometer with Simple Structure and High Locating Accuracy
A phase-sensitive optical time domain reflectometer (Φ-OTDR) can be used for pipeline security. However, the sensing distance (less than 20 km) of traditional Φ-OTDR is too short for the needs of typical oil and gas pipeline monitoring applications (30–50 km). A simple structure Φ-OTDR system utilizing long pulse, balanced amplified detector and heterodyne detection is proposed in this paper and the sensing range is thereby increased to 60 km. Through analyzing the sensing principle of Φ-OTDR, a novel locating strategy is proposed to maintain the locating accuracy at a few meters when a long pulse (5 µs) is used. The increased pulse width deteriorates the time series of each sensing point seriously. In order to eliminate the deterioration, a data processing technique combining wavelet and empirical mode decomposition is applied in this system. The experiment results show that the sensing distance can be increased to 60 km and the locating accuracy is maintained at 6.8 m