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IoT-Based Smart Stick for the Blind
Published in Rashmi Gupta, Arun Kumar Rana, Sachin Dhawan, Korhan Cengiz, Advanced Sensing in Image Processing and IoT, 2022
Varsha Vimal Sood, Kartik Bansal, Nitish Agarwal
Gas sensor: Gas sensors or gas detectors are electronic devices used to detect and/or identify the presence of harmful, toxic, or explosive gasses. These are used to detect gas leaks and smoke as well as their concentrations [23]
Chemical Nanosensors
Published in Vinod Kumar Khanna, Nanosensors, 2021
Why is the development of gas sensors currently being carried out intensively? This is because environmental pollution and toxicants in industrial and domestic environments represent acute problems facing mankind. Gas detection is obligatory in many different fields, e.g., industrial, fuel emission control, automobile exhaust emission control, household security, and environmental pollution monitoring. Gas sensors are utilized in factories, laboratories, hospitals, and almost all technical installations. What gases have evoked special interest? Gases of interest include CO2, CO, NO2, SO2, O2, O3, H2, Ar, N2, NH3, and H2O, and organic vapors such as those of methanol (CH3OH), ethanol (C2H5OH), isopropanol (C3H8O), benzene (C6H6), and some amines (organic compounds and functional groups that contain a basic nitrogen atom with a lone pair).
Ventilation teaching and research using a computerized scale model
Published in Y.J. Wang, R. Larry Grayson, Richard L. Sanford, Use of Computers in the Coal Industry, 2020
The station will be programmed to perform several automatic and manual functions also. By then, the system should be capable of automaticly scanning each sensor output in a predetermined interval, then convert the data to digital information, check for alarms and record all data on disk memory. The operator would call for certain tasks to be performed whenever desired. The operator would also be able to execute certain commands if necessary, such as turning on and off the sensor power, regulator doors, etc. Gas and temperature sensors will be added to the monitoring system. The gas detectors will monitor for potentially hazardous gas build-ups. The information is carried to the computer via shielded electric cable. The computer will be continuously reading the data and is able to make a decision based on what it detects. For example, if the computer finds that a small amount of methane is present in a work area, the computer may divert air from other parts of the mine or it may increase the output of the ventilation fan. If these actions do not correct the problem and the methane concentration still increases, then the computer may cutoff the power to that section of the mine and sound off an alarm.
A neural network for evaluating the concentration of leaked gas clouds detected by TDLAS at oil and gas stations
Published in Petroleum Science and Technology, 2023
Fei Xiao, Jianfeng Li, Xiaochun Zheng, Jingjian Liu, Min Luo, Jiaqiang Jing
Traditional gas detectors can be classified as point and line types. Point-type gas detectors measure the concentration at a certain position. The other line-type gas detectors measure the IC along a fixed optical path. In fact, the TDLAS detector is also a special line-type gas detector, but the laser path involving the distance and path angle are dynamic due to the PTZ component. As the value of IC is associated with the optical path and the concentration distribution, the characteristics of IC from the TDLAS detector are totally different for both point- and line-type gas detectors. As shown in Figure 2, a 100% lower explosion limit (LEL)·m may mean a laser beam passing through a cloud with a 25% LEL concentration and a 4 m width or with a 50% LEL concentration and a 2 m width. Even though the measured IC is the same, the concentrations inside various gas clouds may be different. Most standards such as GB 50493 (2019) and IEC-60079-29-2 (2015) provide guidance for both point- and line-type gas detectors. However, these standards fail to cover the TDLAS detector. Although the TDLAS detector performs better due to the significant advantages in methane sensitivity and area-type leakage detection, the concentration evaluation of detected gas clouds still has not been studied.