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Perovskite SrCoO3 material is synthesized using sol-gel method followed by solid state reaction at three different temperatures 700 °C, 800 °C, and 900 °C. The crystalline structure of the material is confirmed by XRD, and the presence of the functional groups is confirmed by FTIR. The electrochemical performance of the material is carried out using a three-electrode system. The material synthesized at 700 °C exhibits a high specific capacity value of 303 C/g at a current density of 1 A/g, and it exhibits 50% capacity retention after 10,000 charge-discharge cycles at 10 A/g. [ABSTRACT FROM AUTHOR]

For high energy supercapacitor, highly porous materials with accessible active sites are needed. Metal-organic frameworks (MOFs) are trending highly porous materials. Cobalt is one of the electrochemically active materials. In this work, Co-MOF is successfully synthesized using temperature-assisted co-precipitation method. Its crystal structure and functional groups are investigated using X-ray diffractometer and Fourier transform infrared spectroscopy, respectively. Electrochemical energy storage properties of Co-MOF are investigated. Co-MOF synthesized at 150 ˚C exhibits highest specific capacity (374 C g−1) compared to other temperatures synthesized samples. It retains 82.7% of its initial specific capacity after 5000 charge-discharge cycles. [ABSTRACT FROM AUTHOR]

Optically rough mild steel (A36) is illuminated by a coherent source of laser light, develops a bright and dark cigar like granular appearance called as speckle images. The high resolution CCD records these speckle patterns and studied with image processing method to evaluate the roughness of the sample surface. It is demonstrated that speckle imaging method of surface roughness measurement of the object is guaranteed well with the values of stylus profilometer technique. [ABSTRACT FROM AUTHOR]

Easy precision is obtained using a Machine Learning algorithm in student's academic performance analysis. If the semester result for the student is above certain grade, then the student obtained good academic result. On the other hand, if the test for the student is below grade 3 then he or she needs some training or counselling. To improve the students performance and to achieve good grade can be carried out by a machine learning algorithm. In the study of a student's achievement, a Machine Learning method provides easy precision. If a student's semester grade is above a given level, the student has done well academically. If the student's test score is less than a grade three, he or she will need some training or counselling. A machine learning algorithm is used to improve a student's performance and help them to get a good mark. Five methods were utilised to evaluate student performance in this paper: Random Forest algorithm, SVC (Space Vector Machine), decision tree, logistic regression, and Nave Bayes. In comparison to other methods, Decision Tree has a high level of accuracy. It is evident from this research that we might simply train the pupils in the objective aspect by applying machine learning methods. [ABSTRACT FROM AUTHOR]

In this Laser speckle velocimetry, four interrogation windows with different concentration of seeded particles support and progresses the measurement of instantaneous velocity of flow. A laser sheet illuminated micron size seeded particles, gives a moving pattern at the recording plane. Double frame/single exposure laser speckle images are captured, in such a way that second speckle image was shifted exactly in a known direction. But in the case of auto-correlation process, there is a problem of directional ambiguity of flow. To rectify this, spatial shift of second image designed and cross correlation by Fast Fourier Transform technique has been adopted. Correlation strength escalate by reducing in-plane loss by middling displacement of seeded particles. [ABSTRACT FROM AUTHOR]

The current research work, Ni doped CuO nano structured fibres have been manufactured using self-assembled method called innovative spin coater. The prepared nano structures were exposed to various high temperatures like 400 °C, 500 °C and 600 °C and then slowly cooled to room temperature (annealing process). The structural analysis of Ni doped CuO nano fibres have been studied through Field Emmison Scanning Electron Microscope (FE - SEM), elemental composition investigation of the Ni doped nano fibres were examined using Energy Dispersive X- ray spectroscopy (EDS). The degree of crystalline nature existent in the nickel dopped copper oxide nano fibres have been inspected with help of X-ray Diffraction spectrum (XRD). The optical sensitivity of the prepared nanostructures such as absorption, reflectance and transmittance have been explored through UV- Vis spectrum. The attained XRD results of the synthesized copper oxide nano fibres disclose the existence of perfect nano crystalline segment with monoclinic crystal phase. The FE - SEM micro photographs reveal that each developed nickel with CuO nano fibre clearly shows the spherical nano scale crystallites and are completely free from defects and contaminations. The nickel dopped copper oxide nano fibres were annealed at 600 °C temperature evidently divulges the formation of spherical moulded nano structures as equated with nano structures annealed at 400 °C temperature. The forbidden energy band gap value of nickel doped copper oxide nano fibres was found to be about 2. 7 eV. The obtained structural and optical analysis of nickel doped copper oxide nano fibres have been clearly showing that the developed nano structures may have abundant applications in the various gas sensing field. [ABSTRACT FROM AUTHOR]

Surface roughness comparison of polycrystalline silicon solar wafer is carried out by three different methods. Laser speckle images are recorded for the specimen which is illuminated by three different wavelengths. The speckle patterns are transformed into equivalent binary images by soft computing technique. The robust fractal box counting technique is employed for the quantification of surface roughness. The fractal outcome of Atomic Force Microscope image is compared with the fractal outcomes of laser speckle images. The sample roughness is also assessed by conventional stylus profilometer. [ABSTRACT FROM AUTHOR]

Analyzed the surface structure, crystallinity and other physical properties of the low-pressure dry air plasma treated silk fiber. From the scanning electron microscope study showed the slim grooves after plasma treatment. So, plasma radiation hit on the surface of the silk fiber and get some micro range morphology changes occurred. And crystalline ratio also decreased which was useful to enrich the wettability properties of the silk fiber. From the weight loss analysis, it was concluded that some micro portion of silk fiber was etched by plasma treatment. [ABSTRACT FROM AUTHOR]

Surface roughness characterization of plasma textured polycrystalline silicon solar wafer is estimated at different DC potentials by image processing. Laser speckle based Fractal dimension is a cross-scale surface descriptor of roughness. This investigation shows that surface roughness of the samples increases due to plasma processing in the measured range. [ABSTRACT FROM AUTHOR]

In this paper, a highly coherent laser is dispersed from a colloidal form of milk solution,an arbitrary grainy image named as speckle image is formed in observation plane due to Brownian motion. The outcomes shows that the statistical distribution of the intensity. The fluctuating nature of laser speckle in fluid medium is recorded for different concentration of the sample. Time progression of this interference image brings the required information of scattering particles.The aim of this work is the assessment of particle size by laser diffraction method through the dynamic speckle pattern. This laser scattering method helps to describe the corresponding speckle size for different concentration through image processing technique. [ABSTRACT FROM AUTHOR]

In this work, laser speckle imaging technique is used to measure the surface roughness of (Grade- 6062) Aluminium sample is presented. When an optically coarse surface of Al specimen irradiated by coherent laser light, cigar like dark and bright tiny spots of images are formed. This scattering self-interference pattern is called a speckle pattern. A high resolution CCD camera records the subjective speckle pattern. The surface roughness of Al sample is determined by fractal dimension and fractal box counting technique. The conventional stylus profilometer results are matched well with this laser speckle technique. [ABSTRACT FROM AUTHOR]

In this paper, a non-intrusive, unique optical measurement technique of seeding polystyrene granular beads image velocimetry has been described. The flows of seeded particles are illuminated by laser light and double frame-single exposure images are captured at a specified interval of time. Images are segmented into sub interrogation domain and cross correlation of images are evaluated by Fast Fourier Transform method. From the captured images, particle displacement is calculated and then magnitude of the velocity of micron size seeds in the plane is estimated. This technique is most suitable for high density concentration of seeded particles. Laser speckle velocimetry has wide range of pulse separation time and reduction of noise in the estimation of fluid velocity without directional ambiguity. [ABSTRACT FROM AUTHOR]

Surface roughness evaluation of optically rough metal plate (Al-6061) by laser speckle imaging method is reported. When the crust portion of metal is illuminated by the monochromatic laser beam, the reflected light from the surface produce granular speckle pattern due to the composite effect of scattering and interference. The captured pattern is used for roughness assessment by soft computing technique. The results are fair in consent while compared with the conventional stylus profiler. [ABSTRACT FROM AUTHOR]

Displacement of small granular particles during the flow process has been measured by laser speckle correlation with counting of pixel shifting technique. Speckle pattern velocimetry provides instant velocity measurements in a fluid flow. Micron size particles are seeded in the stream, which scatters laser light. With the help of cylindrical lens, a laser sheet designed to illuminate the particles in the measurement plane. CCD is placed perpendicular to the laser sheet to acquire sequential images of the illuminated flow field. The second image is recorded a short time later during which the seeds will have relocated due to the flow. The image pair develops a field of linear displacement vectors. This effort sorts out the ambiguity in direction of displacement by cross correlation. The displacement and velocity measurements are estimated by a novel counting of pixel shifting calculation method. [ABSTRACT FROM AUTHOR]

The compound 4-methyl-N-methyl pyridiniumtosylate has been synthesized as single crystal from the aqueous solution by solution growth method. The crystal morphology changes made by the illumination of Nd:YAG laser of 6 ns pulse width and 10 Hz frequency. The laser brought surface modification of this crystal has been measured. The comparison of DAST before and after the laser persuaded impairment has been analyzed using optical image processing technique. [ABSTRACT FROM AUTHOR]

A power factor correction (PFC) topology with fuzzy logic controller (FLC) for light-emitting diode (LED) lighting applications is presented in this paper. Nowadays, high brightness white LEDs becomes feasible in residential, industrial and commercial applications to replace the incandescent bulbs, halogen bulbs and even compact fluorescent light (CFL) bulbs. Since LED lighting represents a green technology, the issue of power factor is very important. A valley-fill circuit is combined with the single-ended primary inductance converter (SEPIC) to achieve power factor nearer to unity. The fuzzy logic controller is implemented to drive the SEPIC-PFC topology. The performance of the proposed design will be analyzed in terms of power factor using the Matlab/Simulink simulation results. [ABSTRACT FROM PUBLISHER]

The inverter in conventional BLDC motors use hard switching technique, due to which it has low switching frequency and high losses. Active Clamp resonant DC link is proposed to use with BLDC motor. In this paper the performance of BLDC motor using ACRDCL inverter and conventional RDCL is analyzed. The simulation results are found to be in agreement with the expected outcome [ABSTRACT FROM PUBLISHER]

In this paper, the SAZZ Converter with Soft Switching technique is applied to the Fuel Cell System to improve the output voltage to desired value. The Output voltage of this converter is obtained as a DC Voltage, which is connected to an impedance network, to remove the ripples present in the circuit. A 3 phase inverter operating at 180 degree mode is connected with the system. Filtering technique is applied to reduce the Harmonics obtained in the system. Open loop PWM switching is adopted. An Impedance network is connected to reduce the ripples present in the circuit. In order to boost the obtained value this network is connected in form of Z-source with a three phase inverter. This inverter operates at 180 degree mode. Open loop PWM triggering is adopted to obtain AC output and the obtained AC Voltage contains harmonics of both odd and even harmonics of lower and higher order. Higher order harmonics are eliminated with the help of Filters while lower order harmonics are eliminated by a Current Injection technique. Here three different filtering techniques of SAZZ converter are analyzed. Three techniques of Filter are compared and evaluated. This filtering technique is developed to reduce the third harmonic content in load side. Therefore they are suitable to implement a system capable of converting DC to AC with FUEL Cell as DC Source. Other parameter considered is peak to peak (rms) voltage. The study determines that LC filtering technique is most useful mainly due to low harmonic content (third order). FFT analysis is done to obtain values of these three filtering techniques. [ABSTRACT FROM PUBLISHER]

Design of optimal topology for engineering products subject to mechanical loads has been traditionally approached through homogenization and more recently through introducing constraints on perimeter to ensure well-posedness. This paper reports attempts to obtain numerical solution to the problem of maximization of stiffness by distributing a given material in a discretized domain, with constraints on perimeter and appearance of small chattering voids, using Genetic Algorithm. Convergence of the numerical procedure is established and detailed topologies are obtained for various values of volume constraints. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]