Real-Time Model Method Research in Ship Pipeline System Leakage Detecting

2011 ◽  
Vol 105-107 ◽  
pp. 685-688 ◽  
Author(s):  
Hong Hao Yin ◽  
Hui Chen ◽  
Zhong Bo Peng

Leakage of ship pipeline system has become a great hidden danger, which affects safe operation of ship and causes environmental pollution. In order to isolate leaking pipeline safely in emergency conditions, Real-time monitoring of ship pipeline system leakage is very important. In this paper, the real-time models of ship isothermal and thermal pipeline were established with a set of equations which is running synchronized with the actual execution pipeline, and the real-time model method was used to monitor ship pipeline system leakage. If the difference between measured values and calculated values is greater than a certain range, pipeline leakage is identified. The location of leakage is calculated based on pressure gradient. Only pressure, flow and temperature of the first and second end of the pipeline were needed, can this method achieve leakage detecting and locating. According to the analysis and verification from the experimental data, this method has high leakage resolution and positioning accuracy.

2021 ◽  
pp. 174498712110161
Author(s):  
Ann-Marie Cannaby ◽  
Vanda Carter ◽  
Thomas Hoe ◽  
Stephenson Strobel ◽  
Elena Ashtari Tafti ◽  
...  

Background The association between the nurse-to-patient ratio and patient outcomes has been extensively investigated. Real time location systems have the potential capability of measuring the actual amount of bedside contact patients receive. Aims This study aimed to determine the feasibility and accuracy of real time location systems as a measure of the amount of contact time that nurses spent in the patients’ bed space. Methods An exploratory, observational, feasibility study was designed to compare the accuracy of data collection between manual observation performed by a researcher and real time location systems data capture capability. Four nurses participated in the study, which took place in 2019 on two hospital wards. They were observed by a researcher while carrying out their work activities for a total of 230 minutes. The amount of time the nurses spent in the patients’ bed space was recorded in 10-minute blocks of time and the real time location systems data were extracted for the same nurse at the time of observation. Data were then analysed for the level of agreement between the observed and the real time location systems measured data, descriptively and graphically using a kernel density and a scatter plot. Results The difference (in minutes) between researcher observed and real time location systems measured data for the 23, 10-minute observation blocks ranged from zero (complete agreement) to 5 minutes. The mean difference between the researcher observed and real time location systems time in the patients’ bed space was one minute (10% of the time). On average, real time location systems measured time in the bed space was longer than the researcher observed time. Conclusions There were good levels of agreement between researcher observation and real time location systems data of the time nurses spend at the bedside. This study confirms that it is feasible to use real time location systems as an accurate measure of the amount of time nurses spend at the patients’ bedside.


2014 ◽  
Vol 61 (2) ◽  
pp. 270-285 ◽  
Author(s):  
Michael Kleer ◽  
Andrey Gizatullin ◽  
Klaus Dreßler ◽  
Steffen Müller

Abstract The paper encompasses the overview of hardware architecture and the systems characteristics of the Fraunhofer driving simulator. First, the requirements of the real-time model and the real-time calculation hardware are defined and discussed in detail. Aspects like transport delay and the parallel computation of complex real-time models are presented. In addition, the interfacing of the models with the simulator system is shown. Two simulator driving tests, including a fully interactive rough terrain driving with a wheeled excavator and a test drive with a passenger car, are set to demonstrate system characteristics. Furthermore, the simulator characteristics of practical significance, such as simulator response time delay, simulator acceleration signal bandwidth obtained from artificial excitation and from the simulator driving test, will be presented and discussed.


2013 ◽  
Vol 464 ◽  
pp. 194-198
Author(s):  
Ho Sang Ahn ◽  
Seung Yeon Song ◽  
Jae Hwan Ahn ◽  
Dae Gyu Jang ◽  
Jin Chul Joo

We measured chrominance of chrysotile powder using a colorimeter and a luminance meter under different light sources with seven color filters to test feasibility for the real time asbestos detector development. Chrysotile powder was prepared by heating asbestos fabric at 150 °C for 1hr and hydrochloric acid treatment was followed to remove other elements. Refractive index liquid was used as a color changing analyte to observe the change in chrominance of chrysotile. From the measurements, it revealed that a colorimeter was more suitable for the chrysotile detection by the maximum change in chrominance, especially in the short wave length range of blue regions. A luminance meter was not able to separate the difference in chrominance depending on different color and light sources regardless dyeing. It might be due to that reflected light from chrysotile particle was relatively weaker than that from illuminated area. It is our suggestion that the real time monitoring of asbestos in indoor air can be possible using a color sensor, specified to the unique wavelength of dyed chrysotile based on our chrominance data.


Author(s):  
Paolo Pezzini ◽  
Francesco Caratozzolo ◽  
Alberto Traverso

The availability of reliable simulation models can reduce the time required for commissioning test rigs as well as preventing components from suffering serious damage during testing. The aim of this study is to set up and validate, against experimental data, a real-time model referring to the Rolls-Royce Fuel Cell System Limited (RRFCS) hybrid system concept, based on SOFCs. The dynamic model of the SOFC “block” has been developed, run in real-time, and successfully validated against experiments. Initially, the dynamic evolution of the model is considered under constant inputs at steady-state and is compared against experimental data; secondly, transient behaviour is also considered. Step variations of the main air flow, main fuel flow, syngas flow and electrical current were performed. The model can now be employed to carry out the following: performance analysis, design verification, development of control strategies, on-line analysis and integration with Human Machine Interface.


Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3849
Author(s):  
Xiayun Duan ◽  
Yifeng Ding ◽  
Huanna Niu ◽  
Yuzhu Wang

For the correction problem of day-ahead plan deviation caused by energy prediction deviation in day-ahead scheduling stage of photovoltaic greenhouses, an exergy analysis method is used to propose the deviation model of heat required for photovoltaic greenhouses. Based on the deviation model, a real-time optimization scheduling model is established. The deviation model not only considers the non-negligible exergy loss during heating process of pipes, but also considers the difference between heat and thermal exergy affected by the actual indoor temperature. The goal of the real-time scheduling model is to minimize the absolute value of the difference between the energy supply and demand prediction deviation to be corrected and the adjustment of multi-form energy storage and electric loads, so that develop the real-time adjustment plan of energy storage and electric loads. The analysis results of the actual photovoltaic greenhouse show that of the heat required by a greenhouse based on the exergy theory calculation, the exergy loss of the heating process accounts for about 10%–20% of the total thermal exergy required and it cannot be ignored, so the calculation results can reflect the actual heat required more accurately and the greenhouse temperature is more suitable for plant growth. Moreover, the proposed real-time scheduling model can correct the deviation of the day-ahead plan and improve local consumption. The promotion ratio can reach 7%. Finally, the farmers’ electricity purchases cost is reduced. Thereby the effectiveness of the proposed heat deviation model and real-time scheduling model is verified.


Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3879
Author(s):  
Qi Liu ◽  
Chengfa Gao ◽  
Zihan Peng ◽  
Ruicheng Zhang ◽  
Rui Shang

As one of the main errors that affects Global Navigation Satellite System (GNSS) positioning accuracy, ionospheric delay also affects the improvement of smartphone positioning accuracy. The current ionospheric error correction model used in smartphones has a certain time delay and low accuracy, which is difficult to meet the needs of real-time positioning of smartphones. This article proposes a method to use the real-time regional ionospheric model retrieved from the regional Continuously Operating Reference Stations (CORS) observation data to correct the GNSS positioning error of the smartphone. To verify the accuracy of the model, using the posterior grid as the standard, the electron content error of the regional ionospheric model is less than 5 Total Electron Content Unit (TECU), which is about 50% higher than the Klobuchar model, and to further evaluate the impact of the regional ionosphere model on the real-time positioning accuracy of smartphones, carrier-smoothing pseudorange and single-frequency Precise Point Positioning (PPP) tests were carried out. The results show that the real-time regional ionospheric model can significantly improve the positioning accuracy of smartphones, especially in the elevation direction. Compared with the Klobuchar model, the improvement effect is more than 34%, and the real-time regional ionospheric model also shortens the convergence time of the elevation direction to 1 min. (The convergence condition is that the range of continuous 20 s is less than 0.5 m).


2020 ◽  
Vol 14 (4) ◽  
pp. 413-430
Author(s):  
Abdelsatar Elmezayen ◽  
Ahmed El-Rabbany

AbstractTypically, the extended Kalman filter (EKF) is used for tightly-coupled (TC) integration of multi-constellation GNSS PPP and micro-electro-mechanical system (MEMS) inertial navigation system (INS) to provide precise positioning, velocity, and attitude solutions for ground vehicles. However, the obtained solution will generally be affected by both of the GNSS measurement outliers and the inaccurate modeling of the system dynamic. In this paper, an improved robust adaptive Kalman filter (IRKF) is adopted and used to overcome the effect of the measurement outliers and dynamic model errors on the obtained integrated solution. A real-time IRKF-based TC GPS+Galileo PPP/MEMS-based INS integration algorithm is developed to provide precise positioning and attitude solutions. The pre-saved real-time orbit and clock products from the Centre National d’Etudes Spatials (CNES) are used to simulate the real-time scenario. The performance of the real-time IRKF-based TC GNSS PPP/INS integrated system is assessed under open sky environment, and both of simulated partial and complete GNSS outages through two ground vehicular field trials. It is shown that the real-time TC GNSS PPP/INS integration through the IRKF achieves centimeter-level positioning accuracy under open sky environments and decimeter-level positioning accuracy under GNSS outages that range from 10 to 60 seconds. In addition, the use of IRKF improves the positioning accuracy and enhances the convergence of the integrated solution in comparison with the EKF. Furthermore, the IRKF-based integrated system achieves attitude accuracy of 0.052°, 0.048°, and 0.165° for pitch, roll, and azimuth angles, respectively. This represents improvement of 44 %, 48 %, and 36 % for the pitch, roll, and azimuth angles, respectively, in comparison with the EKF-based counterpart.


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