Search

In this paper, Ba-doped SnO2 (SnO2:Ba), Mg-doped SnO2 (SnO2:Mg) and Ce-doped SnO2 (SnO2:Ce) nanostructured thin films were prepared on the glass substrate via a simple and low-cost nebulizer spray pyrolysis method. The crystal structure and morphology of all the samples were investigated by X-ray diffraction (XRD) and field-emission-scanning electron microscopy (FE-SEM), respectively. XRD results suggest that all the samples are polycrystalline with the tetragonal rutile structure. FE-SEM analysis exhibits a uniform surface morphology with homogenous distribution of grains. The transmittance measurement suggests that SnO2:Ba sample exhibits high transparency above 90% in the visible region. We find that doping causes an increase in the band gap, this behavior is explained by the Burstein–Moss effect. Two emission bands in the ultraviolet and visible regions are observed in the photoluminescence spectra. Hall effect measurement reveals that all the samples are degenerate and exhibit n-type semiconducting nature with carrier concentration in the order of 1018 cm−3. Ba doping induces the lowest resistivity of 0.047 Ω·cm associated with an increase in carrier concentration of 8.38 × 1018 cm−3 and mobility of 15.87 cm2 V−1 s−1. In contrast, the incorporation of Mg and Ce in SnO2 reduces the mobility and conductivity, which may be associated with the grain boundary scattering.

The V (5 wt.%) doped In2O3 (V: In2O3) thin films with the thickness of 50–150 nm were deposited on to glass substrate by electron beam evaporation technique and the deposited films were annealed at 200 °C in air for 2 h. The annealed films were characterized by structural, electrical, optical and photoluminescence properties. X-ray diffraction (XRD) pattern shows that the film is an amorphous nature. The negative sign of the Hall coefficient indicates the n-type conductivity. Experimental results show that the resistivity and transmittance of the films are strongly influenced by film thickness and post deposition annealing. A minimum resistivity of 6.22 × 10−3 Ω cm, a carrier concentration of 5.23 × 1019 cm−3, a Hall mobility of 19.21 cm2 V−1 s−1 and a figure of merit of 1.04 × 10−4 Ω−1 are observed for the film with thickness of 150 nm. After annealing the films, the average transmittance is enhanced up to 84% in the near infrared region. The blue-shift of optical band gap is found to increase from 1.62 to 2.25 eV with increasing the thickness, whereas the refractive index decreases from 2.92 to 2.64. Structural disorder was observed from the Urbach’s tail. A prominent and high intense orange emission is achieved at room temperature, which may be attributed to oxygen deficiencies or intrinsic defects.

Saccharin is used in food as an artificial sweetener which is very much dangerous for the human body. For this reason, it is very essential to identify the existence of this substance which is likely difficult in conventional way. But PCF based device can provide us an opportunity to detect the substance practically. This work proposes two different forms of hollow-core photonic crystal fibers (HC-PCF) with hexagonal cladding for saccharin sensing. The sensing properties of the proposed sensor is examined by the finite element method (FEM). Numerical outcomes show that the maximum possible relative sensitivity of the proposed sensor is as high as 93.81% and 94.68 % for circular and hexagonal shaped core, at operating wavelength 1.4 μm respectively. Due to such a promising result, the proposed HC-PCF sensor can be used for saccharin sensing effectively.

In this paper, the structural, optical and photoluminescence (PL) features of the spray deposited Ba:SnO2 thin films with varying thickness have been investigated. X-ray diffraction analysis showed that Ba:SnO2 thin films have a polycrystalline tetragonal rutile structure and nanometric dimensions. The preferred directional growth of nanocrystalline was along direction. The crystallite size of the samples was calculated using the Debye-Scherrer equation. With an increase in film thickness, the crystallite size decreased from 11.72 to 5.27 nm, while crystal imperfections, viz. lattice strain, degree of lattice distortion and dislocation density increased. The influence of film thickness on the transmittance and reflectance was investigated by using UV-Vis spectral data. The average visible transmittance of Ba:SnO2 nanocrystalline declined from 85 to 79% at 550 nm with an increase in film thickness. Ba:SnO2 nanocrystalline exhibited a slight red-shift in the absorption edge and the optical band gap was found to decrease in the range 3.94 to 3.64 eV. Near band-edge UV emissions band at ~ 402 nm were observed in the PL spectra which are attributed to the defect levels originating from the oxygen vacancies.

Moving object detection has introduced a new challenging horizon in the era of image processing. The main challenge to detect moving objects in all environments because of the complex background. This paper proposes a method that detects a moving object more accurately in almost all the environments. Background subtraction is used in our proposed method for detecting moving objects where the Sauvola algorithm is used on a subtracted image for binary conversion. Median filtering and boundary labeling are used to increase the accuracy of moving object detection. Finally, a morphological operation is performed in our proposed method for detecting the moving object. We tested our proposed method on Wallflower datasets and compare the results of moving object detection on the basis of recall, precision and F-measure with other existing methods. Our proposed method attained successful results for detecting the moving object.

Precise detection and classification of brain tumors at a reasonable time is vital to enhance the survival of a patient. But due to the big dimensional and anatomical diversity between brain tumors, this is a difficult job. In this contribution, we are proposing an improved spatial fuzzy c-mean (SFCM) for brain tumor segmentation and a quadratic support vector machine (QSVM) for tumor type classification. When applied to the BraTS 2018 dataset, the acquired segmentation outcomes were shown to be 7.16% and 12.78% better than the conventional fuzzy c-mean (FCM) and k-mean. This method assists radiologists in understanding the medical image and gives a second opinion.

In this work, a refractive index sensor based on hollow-core photonic crystal fiber (HC-PCF) with hexagonal shaped cladding is proposed. The sensing performance of the proposed sensor is evaluated by the finite element method (FEM) for two different core geometry (circular and hexagonal) and sorbitol is used as sensing sample. Simulation results show that the proposed sensor exhibits relatively high sensitivity of 96.198 % and 94.124 % for circular and hexagonal shaped core, respectably, at operating wavelength of 1.25 µm, In addition, the confinement loss of the proposed sensor is as low as 2.24×10−09 and 1.67×10−10 dB/m for circular and hexagonal shaped core, respectively. Owing to having good sensing performance, the proposed sensor can be competent for sorbitol sensing.

Recently, flying ad hoc networks (FANETs) are considered as an emerging technology by creating opportunities to support numerous real time applications such as traffic monitoring, remote sensing, disaster monitoring, search operations, and border surveillance. However, several challenges are still exist for fast and precise packet delivery regarding these applications. Efficient real time routing is one of the vital challenges among them due to speed variations of its flying nodes and high topology changing probability. We investigate a routing strategy for two different types of routing protocols, e.g. AODV and DSDV. A three dimensional (3D) graph is used for analyzing the protocol performances by considering two other aspects simultaneously, i.e., velocity of flying node and network size. We perform the simulation scenarios using NS2 network simulator. Simulation results indicate that AODV shows better performances for most cases while DSDV performs well in case of end to end delivery.

A simple dual-core D-shaped plasmonic refractive index (RI) sensor with an open-arch channel is introduced in this paper. A thin plasmonic gold layer is inserted on the slotted portion, which makes the sensor cost effective. By introducing a ring in the flat surface of the D-shaped structure, the coupling effect is increased, which enhances sensor performance. The commonly used finite element method is applied to characterize sensor performance. Numerical investigation under the wavelength interrogation method shows maximum spectral sensitivities of 16,000 nm/RIU and 17,000 nm/RIU along with corresponding resolutions of 6.25 × 10 − 6 R I U and 5.88 × 10 − 6 R I U for x and y polarizations, respectively. In tandem with this, maximum amplitude sensitivities governed by the amplitude interrogation method are calculated at about 2 , 603.7000 R I U − 1 and 3 , 432.1929 R I U − 1 for x and y polarizations, respectively. The proposed sensor exhibits high figures of merit of 320 R I U − 1 and 283.33 R I U − 1 for x and y polarizations, respectively, in the RI detection range of 1.33 to 1.44. Moreover, the impact on sensitivity with the overall sensor behavior is analyzed by altering geometrical parameters such as pitch, air hole diameter, and gold layer thickness. So, with an eye toward sensor performance and economic viability, this sensor is assignable to bio-sensing applications.

In this work, alkaline Ba doped SnO2, BaxSn1-xO2 (0.00 ≤ x ≤ 0.05), thin films have been synthesized by a cost-effective nebulizer spray pyrolysis method. X-ray diffraction analysis reveals that undoped and Ba doped SnO2 films are polycrystalline with tetragonal rutile structure. Field emission scanning electron microscopy analysis shows a morphological transformation of the crystallite grains from pyramidal-shaped to cubic-shaped. 3% Ba doped SnO2 sample exhibits excellence properties such as minimum resistivity (3.10 × 10−3 Ω cm), high mobility (21.47 cm2 V−1s−1) and maximum visible transmittance (86% at 550 nm). The optical band gap is estimated to be 4.04, 3.92, 3.89 and 4.10 eV for the samples prepared with Ba contents of 0, 1, 3 and 5%. In the photoluminescence investigation, a dominant blue emission band at ~ 474 nm is observed in the SnO2, whereas Ba doped SnO2 samples exhibit a strong violet emission band at ~ 430 nm. These emission bands can be attributed to the presence of defect-related states inside the band gap of SnO2.

In this research, a highly sensitive porous core octagonal photonic crystal fiber has been exhibited for sensing Ethanol (n=1.354), the most valuable chemicals used in the industries all over the world. The proposed PCF contains five rings which are a combination of circular and elliptical shaped air ducts in the outer portion and two rings containing circular air ducts in the inner region. The principal typical features like relative sensitivity and confinement loss have been observed at an extensive order of wavelength from 0.8 μm to 1.9μm using Finite Element Method (FEM). It has represented the sensitivity and confinement loss to a new extent for ethanol sensing comparing to the previous PCFs. It has been found that enlarging the diameter of inner region upgrades the relative sensitivity. From this study, we have obtained a higher relative sensitivity of 69.90% and lower confinement loss of 2.00×10−10 (dB/m) for ethanol (n=1.354) at the wavelength λ=1.33μm.

In this study, we have presented a porous-core octagonal photonic crystal fiber (P-OPCF) that is applicable for ethanol sensor. The numerical investigation has been occupied by using a finite element method (FEM) that is full vectorial. It is noticed that the incremental value of the diameter of cladding and core holes increase the sensitivity and decrease the confinement loss. In addition, by changing the first ring shape of air holes in the region of cladding, we may also change the sensitivity. The proposed porous shape PCF has been designed for chemical such as ethanol sensor and here the results have been shown for ethanol (n = 1.354). The investigated sensitivity is about 72.65% and the confinement loss is about 8.0645×10−11 dB/m at the operating wavelength 1.33 µm. The range of operating wavelength is from 0.9 µm to 1.8 µm. The shape of the core region is hexagonal which contains three layers with circular air holes and cladding region is octagonal containing five layers with circular air holes.

Cardiac disorder leads to abnormal variability in the RR intervals. Hence accurate identification of such beats and pattern recognition are important for effective decision making. In this work, a platform using MATLAB based Graphical User Interface (GUI) is developed for automatic detection of infected or non-infected heartbeat conditions. Four subjects having normal sinus rhythm, atrial fibrillation, and arrhythmia respectively are investigated by analyzing distribution of power and statistical features (heart rate, form factor, kurtosis, skewness, and LF/HF ratio). RR interval of affected subject is less than the normal heart beat. Moreover, heart rate, kurtosis, and skewness are higher but LF/HF ratio is lower for affected heart beats. The proposed classification procedure is tested on MATLAB based GUI platform and the results are compared with real report obtained from medical. The result provides a significant clinical advantage, and matches the doctor's opinion. A new platform can be found to detect the condition of heart within very short time.

ECG machines are usually used for medical diagnosis of heart activities of human body now days. It has created different types of noise and interference based on interfaces between ECG machines and human body. It can change the real amplitude and duration of the signal. In this paper we improved moving average filter and proposed moving average weighted window filter. We have also proposed an algorithm based on forward difference quotient and threshold for noise elimination of ECG signal. The numerical value of different performance parameters such as 23dB of SNR, lower of MSE, and approximately 1 of correlation is provide better clarification of simulation results than others and prove the robustness of the algorithms.

A vehicle tracking system is very useful for tracking the movement of a vehicle from any location at any time. In this work, real time Google map and Arduino based vehicle tracking system is implemented with Global Positioning System (GPS) and Global system for mobile communication (GSM) technology. GPS module provides geographic coordinates at regular time intervals. Then the GSM module transmits the location of vehicle to cell phone of owner/user in terms of latitude and longitude. At the same time, location is displayed on LCD. Finally, Google map displays the location and name of the place on cell phone. Thus, owner/user will be able to continuously monitor a moving vehicle using the cell phone. In order to show the feasibility and effectiveness of the system, this work presents experimental result of the vehicle tracking system. The proposed system is user friendly and ensures safety and surveillance at low maintenance cost.