Gas Sensors: A Review Zainab Yunusa; Mohd. Nizar Hamidon; Ahsanul Kaiser ...
Sensors & transducers,
04/2014, Volume:
168, Issue:
4
Journal Article
Peer reviewed
Open access
In this paper a review of different technologies for gas sensors is presented. The different types of gas sensors technologies including catalytic gas sensor, electrochemical gas sensors, thermal ...conductivity gas sensor, optical gas sensor and acoustic gas sensor are discussed together with their principle of operation. The Surface Acoustic Wave Gas Sensor technology is discussed in greater detail. The advantages and disadvantages of each sensor technology are also highlighted. All these technologies have been used for several decades for the development of highly sensitive and responsive gas sensors for the detection of flammable and hazardous gases. However, for improved sensitivity and selectivity for these sensors, future trends and outlook for researchers are suggested in the conclusion of this article.
Coverage problem is an important issue in wireless sensor networks, which has a great impact on the performance of wireless sensor networks. Given a sensor network, the coverage problem is to ...determine how well the sensing field is monitored or tracked by sensors. In this paper, we classify the coverage problem into three categories: area coverage, target coverage, and barrier coverage, give detailed description of different algorithms belong to these three categories. Moreover, we specify the advantages and disadvantages of the existing classic algorithms, which can give a useful direction in this area. PUBLICATION ABSTRACT
Drivers' individual difference is one of the key factors to influence the accuracy of driving behavior model. The accuracy of model should include the effect characteristics of individual difference ...on driving behavior. The overtaking process was the research object to study the individual characteristics of driving behavior. The operation data of accelerator and steering wheel of each driver was analyzed with the character of time series. Based on both of the operation data, hidden Markov model (HMM) was employed to model the individual characteristics of driving behavior. Two individual models were built for each driver, one trained from accelerator data and one learned from steering wheel angel data. The models can be used to identify different drivers and the accuracy can reach to 85 %. It proved that individual difference is one factor which cannot be ignored in driving behavior model, and HMM has effectiveness in modeling it. PUBLICATION ABSTRACT
As being an essential tool for estimating spatial continuous data, interpolation methods have been applied to various disciplines concerned with the Earth's surface. In the paper, six spatial ...interpolation algorithms, including an internationally popular ANUDEM method and five other commonly used interpolation methods, were applied in three different landform regions, that is, hills, mountains and alpine area. Quality analysis and accuracy comparison were carried out using random point check, overlay comparison between derived contours with original ones, and 3D visualization analysis etc. Experimental results show that the accuracies of DEMs generated by ANUDEM are the highest. IDW method ranks the second. TIN, Kriging and natural neibourhood methods have similar accuracy, and the spline-function method is the last. For a specific interpolation method, the greater the terrain undulates, the lower the accuracy of the generated DEM is. PUBLICATION ABSTRACT
For the purpose of measuring the electron affinity of Astatine, a versatile tool for ion beam line up is proposed. Apertures in the ion optics are used to guide the beam and traditionally the current ...is measured on the apertures in order to detect the presence of an ion beam. By slitting the aperture into four separate pieces, the aperture current can also be used to determine the direction of the misalignment and the size of the ion beam diameter. A 4-channel pico ammeter with optical LED indication of the ion beam position is suggested in an analog/digital hybrid design. The design utilizes two charge/current-to-digital chips in a microcontroller design. This work is an important contribution to an ongoing project with the objective to determine the electron affinity of Astatine which is a potential «-radiation agent in radioimmunotherapy.
Identifying inter-frame forgery is a hot topic in video forensics. In this paper, we propose a method based on the assumption that the optical flows are consistent in an original video, while in ...forgeries the consistency will be destroyed. We first extract optical flow from frames of videos and then calculate the optical flow consistency after normalization and quantization as distinguishing feature to identify inter-frame forgeries. We train the Support Vector Machine to classify original videos and video forgeries with optical flow consistency feature of some sample videos and test the classification accuracy in a large database. Experimental results show that the proposed method is efficient in classifying original videos and forgeries. Furthermore, the proposed method performs also pretty well in classifying frame insertion and frame deletion forgeries. PUBLICATION ABSTRACT
In the present investigation, we report on the performance of a room temperature ammonia gas sensor based on Polyaniline-ZnO nanocomposite. The nanocomposite film was fabricated using spin coating ...method on glass substrate. Polyaniline-ZnO nanocomposites were characterized for their structural as well as surface morphologies and ammonia response was studied. The structural (XRD) analysis showed formation of nanocrystalline ZnO while polyaniline exhibited amorphous nature. Morphological analysis using scanning electron microscopy (SEM) of the nanocomposite reveled uniform distribution of ZnO nanoparticles in the PANi matrix. The nanocomposite showed the maximum response of ~14 % upon expose to 100 ppm NH^sub 3^ at room temperature. PUBLICATION ABSTRACT
Electroencephalographic (EEG) arousals are generally observed in EEG recordings as an awakening response of the human brain. Sleep apnea is a major sleep disorder. The patients, with Severe Sleep ...Apnea (SAS) suffers from frequent interruptions in their sleep which brings about EEG arousals. In this paper, a new method for Segmentation and Filtering process of EEG sensor database signals for finding sleep arousals using Chebyshev and Modified Wavelet Algorithm is proposed. The Segmentation Algorithm appears as various features extracted from EEG Data’s and PSG Recordings. The Chebyshev Equiripple Filter is used in Filtering algorithm and then MSVM M-Support Vector Machine was utilized as Classification Tool. Algorithms are performed and different features are extracted and the ROC characteristics are performed. The extracted features are Delta, Gama, Beta, Alpha, Sigma of the EEG signal, EEG Signal Mean, EEG Signal Standard Deviation, EEG Signal Peak Signal to Noise Ratio PSNR, and EEG Signal Normalization. MSVM tool showing EEG signals results.
Nanocrystalline CdSnO3 powder was synthesized by cost effective simple wet-chemical route. The technique was found to be useful for large scale production of nanocrystalline CdSnO3 powder. The ...prepared CdSnO3 powder was fired at 600 oC. Structural, microstructural, optical and thermal studies of the powder were carried out. The CdSnO3 powder was associated with nanocubes with average side length of about 100 nm. Thick films of CdSnO3 powder were prepared by screen printing method and fired at 500 oC to remove organic part adhesive material. Thick film based sensors showed high response and selectivity to NO2 gas. The excellent NO2 response may be due to porous structure and nanocrystalline nature of CdSnO3 powder.
There has been given the solution of the technical problem of separate measurement of parameters of inductance coils and inductive primary converters on alternating current without application of ...potential-current signals. As a measuring circuit the scheme of voltage divider with active-inductive two-pole is used, and as an output signal there has been used the angle of phase shift between two output voltages of the measuring circuit. For forming the output signal temporal separation of measurement channel is used. The advantages of phase method are mostly due to capacity of using microcontrollers. In the technical solutions under consideration the microcontroller regulates the measuring process and develops the measurement results.
