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In this study, the controlled input parameters namely welding speed and spindle speed were optimized by Taguchi method for reinforcement of copper particulates in aluminium alloy (AA6061-AA6063-T6). High carbon and high chromium steel i.e. tool steel D2 type material is used as a friction stir welding tool. Subsequently, the effects of the process parameters were investigated. The signal-to-noise ratios and analysis of variance were applied for statistical analysis. The outcome shows welding speed is the significant parameter than spindle speed. Under the optimum process parameters, 1400 rpm with 16 mm/min were shown best values such as 61.60 MPa for ultimate tensile strength and 91 hardness values. It means moderate spindle speed and lower welding speed develop higher heat. Subsequently, it is also shown that the feasibility of signal-to-noise ratio is responsible to improve welding quality after reinforcement.

The purpose of this study was to provide an overview of the effect of elevated temperature on the behavior of concrete materials. The effects of elevated temperatures on the properties of common portland cement concretes and manufacturing materials are summarized. The effect of elevated temperature on conventional concrete, GGBS concrete and BFS concrete is considered and the performance is compared with the strength of conventional concrete. Concrete in case of an unexpected fire, the properties of the concrete will change after the fire. The building must be designed to withstand high temperatures and also mainly fire. When exposed to high temperatures, such as during a fire, the mechanical properties of concrete such as strength, modulus of elasticity and volume stability are significantly reduced. Concrete structure is exposed to high temperatures, it degrades in many different ways, such as color, compressive strength, elasticity, and high temperature affects concrete density and surface appearance

This review summarize that autism is a complicated disorder that develops from the union of chromosomal and environmental factors by fundamental discoveries from the genetic and epidemiological research departments. Specific alleles identification has contributed significantly to the autism puzzle. As centers to the centers for disease-based control and prevention(CDC), ASD is diagnosed more in boys than girls. This neurobehavioural disorder is usually seen by the age of 3 years. Intense difficulties in social interaction and communication with other people, restricted interests, stereotyped responses to situations, and other repetitive morphological patterns of behavior are symptoms or signs related to autism. Complicated, multigenic interactivity and practicable environmental offerings are to be involved by Etiology. For more distant comprehension of the complicated etiology for autism, research fixating on the consequence of gene by gene interactivities or genetic vulnerability to detrimental environmental challenges can be mentioned. The mouse model system uses environmental challenges to divergent gene expression and cell pathology as early in development and supplies an efficient way to manipulate candidate or constituent genes for autism susceptibility experimentally.

This study demonstrates the performance enhancement of drill bits during dry cutting operation of LM6 aluminum alloy and bright mild steel using optimized Diamond-Like-Carbon (DLC) coatings. DLC coatings are deposited using Plasma Enhanced Chemical Vapour Deposition (PECVD) process by varying the process parameters, bias voltage, bias frequency, gas mixture, and working pressure. DLC coatings were grown over the silicon, high-speed steel, and stainless-steel pin substrate. Coating’s chemical, composition, topography, and mechanical properties measurements were checked using Fourier Transform Infrared (FTIR), micro-Raman spectroscopy, Atomic Force Microscopy, and intrinsic stress & nano-hardness/micro-hardness tester, respectively. Coating deposition and optimization were carried out as per the Taguchi method. Further, the optimized DLC coatings tribological test and the effect of DLC coating on the tool life were performed. Results showed that the DLC-coated substrate had less wear loss and coefficient of friction than the uncoated substrate. The dry-cutting test showed that coated drill bits produce a better surface finish and consume less power in the drilling operation than uncoated drill bits. This is due to the low coefficient of friction and low wear loss of the DLC coatings.

This paper presents a new optimized winding and core design for improved performance of an induction machine. The performance improvement is attained by space harmonic reduction in the winding magnetomotive force (MMF). In the proposed design, the new conductor distribution of the winding and its slot positions are obtained by solving an optimization problem which maximizes the fundamental component of the MMF and reduces certain harmonic components in it, number of which depends on the number of slot per pole per phase. The novel formulation of the optimization results in the modified slot sizes while keeping the width of stator and rotor teeth same as that for the conventional machine. In the proposed design, for certain machine rating, when compared with conventional machine the active length of conductor and the amount of iron is unchanged. However, the winding overhang reduces which leads to copper saving ( $$\approx $$ 6.46%), less winding resistance ( $$\approx $$ 6.5%) and leakage reactance ( $$\approx $$ 7.69%) and finally resulting in decreased total copper losses ( $$\approx $$ 21.6%). Also, improvement in the steady-state torque and efficiency and decrease in the maximum flux density in core is obtained with the proposed machine design.

Psoriasis is a chronic inflammatory skin disease which is identified by the appearance of erythematous that is clearly demarcated, scaly plaques. It is a skin disease seen regularly around the elbow, scalp, trunk, and also on the knees. Psoriasis is a commonly occurring chronic disease with no cure. In psoriasis, which is thought to be an immune system-related problem, the cells of the skin grow quicker than normal cells. The rapid turnover of cells is responsible for the dry scaly patches seen clinically, also called plaque type of psoriasis. The etiopathogenesis of psoriasis is not yet fully understood. It is considered an outcome of some alteration of the cells in the immune system, which fights infections, but here, it attacks healthy cells, which is the problem. Researchers believe both environmental and genetic factors play a role. It is commonly known that psoriasis is not contagious as it does not spread by air or water. There is a chance of increasing the risk of acquiring psoriasis, also worsening the disease severity by smoking and tobacco consumption. Anyone irrespective of age or gender can develop psoriasis. Psoriasis is divided into various kinds: plaque, nail type, guttate, or inverse, also pustular. The most commonly occurring type of psoriasis is plaque psoriasis, seen with itchy, dry, scales covering patches of skin that are raised.

A study was carried out to identify and isolate pathogenic bacterial population present on the common gadgets of college going students. These gadgets if harboured with microbes can cause serious diseases to the bearer causing serious impact on their health. A total of 100 samples of college bags, purses, wrist watches and mobile phones of staff and students from the college campus were randomly collected.

Background: Lung cancer causes more deaths than most other cancers. Conventional sputum cytology (CSC) has low diagnostic yield for lung cancer. Thus, there is a need for rapid, accurate and cost-effective test for detecting lung cancers. Aims: 1). To study sensitivity, specificity and accuracy of Acridine Orange staining with fluorescence microscopy (AOFM) in detection of lung cancer against histo-pathology and fine needle aspiration cytology (FNAC) results. 2). To compare results of AOFM and CSC in diagnosis of lung cancer. Settings and design: It was a diagnostic test evaluation conducted at a tertiary care institute over a period of 24 months. Material and Methods: Sputum samples of 60 patients suspicious of lung cancer were examined using AOFM. After staining with Acridine Orange, exfoliated cells in the sputum samples were categorized as benign or malignant based on the type of fluorescence they emitted when examined under a fluorescence microscope, and results were compared with histo-pathology and/or FNAC reports. Statistical analysis used: Chi-square test, Cohen’s kappa statistic etc. Results: AOFM had sensitivity, specificity and accuracy of 92.31%, 87.67% and 90.24% respectively when compared with histopathology and/or FNAC. P=0.0000026 implies significant difference between sensitivities of AOFM and CSC (30.77%). There was significant difference between AOFM and CSC in context of specificity [P=0.04] and accuracy [P=0.05]. Conclusion: AOFM in the patients with suspected lung cancer is a useful ‘first diagnostic test’. It is a rapid pre-screening tool which will reduce cost of cyto-diagnosis in under-served and remote areas. Keywords: Acridine orange, Fluorescent microscopy, Lung cancer, Sputum cytology.

We report the method of tuning the thermal conductivity through the composition of multiwall carbon nanotube (MWCNT) dispersed ethylene glycol based nanofluids. The structure and properties of the MWCNTs were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Raman spectroscopy and thermogravimetric analysis. A parallel plate thermal conductivity (PPTC) set up was fabricated and used for measurement of thermal conductivity of the nanofluids. We have prepared ethylene glycol based nanofluids containing 0.05, 0.1, 0.15, 0.20, 0.25 and 0.35 wt% of MWCNTs. The thermal conductivities of these fluids were measured by keeping them between the two (parallel) plates, referred as the hot and the cold plates, of the sample holder in the PPTC apparatus. The lower plate was water-cooled and the upper plate was heated. The temperature of the hot plate was varied between 35 and 80 °C. The thermal conductivity of the fluids was calculated using the one-dimensional heat conduction equation. According to our observation, an efficient heat transfer occurs through the nanofluids with an optimum concentration of 0.20 wt% of CNTs. Our work demonstrates the importance of the composition of the nanofluids and their structural defects in heat transfer.

The work summarizes the review of use of High Entropy Alloy in the Friction Stir Welding. When High Entropy Alloy is utilized in the Friction Stir Welding the resultant mechanical, metallurgical as well as corrosive properties show the influence of HEA base material properties. The Process used to obtain HEA provides base properties affecting the microstructural impact due to heat generation in FSW. Taking into account HEA, FSW too improve the welding properties of the material. The grain size was affected by heat generation and pressure of rotational as well as transverse speed, and could be differentiated in different zones (SZ, HAZ, and TMAZ) and sides (advancing, retreating, top, and bottom). Results of misorentation, HABs, and LABs were influences by the type of recrystallization. GGAE are associated to HABs and SFE to heating phenomenon, so overall it is HEA reaction to the heat generation in different areas and its effects seen in recrystallization of grains.

A red phosphor LaSrAl3O7:Eu3+ were synthesized by the solution combustion technique. Their structural and luminescent properties were investigated. The Eu3+ doped LaSrAl3O7 phosphors were excited by n-UV light and exhibited a prominent red emission which is due to the D →F transitions. The incorporation of Li+, Na+, and K+ ions as compensator charge, the luminescence intensity of LaSrAl3O7:Eu3+ greatly enhanced. Addition of Li+ ions in the phosphor shows strongest emission among used charge compensators. The CIE chromaticity (x, y) of LaSrAl3O7:Eu3+, Li+ sample were obtained (0.68, 0.31) and it is close to the standard red chromaticity of NTSC. LaSrAl3O7:Eu3+, Li+ is a good candidate phosphor for red light emitting diodes.

The field of autonomous robotics is growing at a rapid rate. The trend to use increasingly more sensors in vehicles is driven both by legislation and consumer demands for higher safety and reliable service. Nowadays, robots are found everywhere, ranging from homes, hospitals to industries, and military operations. Autonomous robots are developed to be robust enough to work beside humans and to carry out jobs efficiently. Humans have a natural sense of understanding of the physical forces acting around them like gravity, sense of motion, etc. which are not taught explicitly but are developed naturally. However, this is not the case with robots. To make the robot fully autonomous and competent to work with humans, the robot must be able to perceive the situation and devise a plan for smooth operation, considering all the adversities that may occur while carrying out the tasks. In this thesis, we present an autonomous mobile robot platform that delivers the package within the VNIT campus without any human intercommunication. From an initial user-supplied geographic target location, the system plans an optimized path and autonomously navigates through it. The entire pipeline of an autonomous robot working in outdoor environments is explained in detail in this thesis., Comment: 56 pages, Bachelor Thesis

This paper presents a new winding design that is optimized for space harmonic reduction in the magneto-motive force produced by a fractional slot concentrated winding. The objective of the optimization is to achieve an optimal distribution of the conductors in slots such that the total harmonic distortion is minimum in the winding function of each phase. A generalized mathematical derivation of winding function and its harmonic amplitude factor is presented in terms of the number of conductors per slot. The proposed optimization has been applied on 9-slot 8-pole, 12-slot 10-pole, and 24-slot 22-pole windings for obtaining optimized design. The permanent magnet synchronous machines are designed for all the cases of slot-pole combination. Both the conventional and optimized windings are compared in terms of magneto-static and dynamic performance obtained from FEM analysis. The proposed winding results in a significant reduction to all non-working harmonics of air-gap flux distribution. A reduction of torque ripples has also occurred in the proposed optimized winding motor design.

This paper presents design of a variable frequency drive for two phase operation of induction motor to develop a standalone PV system. The speed of motor varies automatically with changing solar irradiation, such that it always extracts maximum power from PV source which improves efficiency of the system. This PV system consists of two power conversion stages, of which one extracts maximum power from solar array. The other provides two phase AC supply required for two phase operation of induction motor. V/Hz speed control method is employed to regulate the speed of motor. The two phase operation of single phase induction motor eliminates use of centrifugal switches and capacitors for starting, which improves reliability of system. In this paper simulation of two phase induction motor solar drive is carried out in MATLAB and results show that the speed of motor is adjusted with varying irradiation and constant temperature of solar array to always operate at maximum power point.

The output voltage of a multilevel inverter is a stair-case waveform. The quality of output voltage in multilevel inverter depend on the switching angles. In this paper, a simple method to compute the switching angles using a numerical series of natural numbers is presented. The series of triangular numbers, Fibonacci numbers, odd numbers, even numbers, and geometric series are used in switching angle calculation. Five different switching angle expressions corresponding to each numerical series are derived. From the analysis of the resulting quasi-square waveform, it is found that the odd number series method presented in this work produces an output voltage waveform with low total harmonic distortion. The results are shown for five level quasi-square waveforms. Based on the total harmonic distortion, the proposed methods are compared with the optimal switching angles that are reported in the literature. From the comparison, it is found that the total harmonic distortion in output voltage obtained by odd number series method is close to the minimum value reported in the literature. The method presented in this work computes switching angles without using complex algorithms and/or by solving non-linear equations.

This paper presents a control logic for the inversion and stabilization of the reaction wheel pendulum. The inverted pendulum control has the applications in the fields of robotics, rocket propulsion control and self-balancing vehicles. The control logic in this paper was designed using the nonlinear control techniques. Control logic for inverting the pendulum was designed using passivity-based control and the control logic for balancing the pendulum in the inverted position was designed using backstepping control. The final control logic was designed by incorporating proper logic for switching the control between the two control logics. The simulation results are presented and explained substantiating the designed control logic.

In system like telescopes where motion is precisely controlled at very low speeds, nonlinear disturbances are observed in the velocity profile which arise due to commutation, friction, backlash and sinusoidal variation of the electromagnetic torque. Also, the sinusoidal disturbances present, which are mainly generated due to imbalances in load and intermediate drive train components like shafts, gears, couplings etc. To mitigate the effects of the disturbances on the system a dual motor setup is designed and developed in laboratory where one motor drives the axis and the other motor compensates the disturbances. The effectiveness of the setup in case of sinusoidal disturbances is evaluated with the help of dSPACE DS1104 HIL controller interfaced with Matlab Simulink. The controller drives the setup using one motor, extracts the sinusoidal disturbances from the velocity profile and applies the required compensation using the other motor. It is observed that the dual motor configuration effectively compensates the disturbances induced by imbalances both during open and closed loop control.

The output voltage waveform of a multilevel inverter is a quasi square wave. The quality of a quasi square wave depends on the switching angles. In this paper, a simple generalized method to compute the switching angles using a numerical series of natural numbers is presented. From the analysis of resulting quasi-square waveform it is found that the method presented in this work produces a output voltage waveform with low total harmonic distortion. The results are shown for five to eleven level quasi-square waveforms. Based on the total harmonic distortion the proposed method is compared with the optimal switching angles that are reported in the literature. From the comparison, it is found that the total harmonic distortion in output voltage obtained by generalized numerical series method is close to the minimum value reported in the literature. The method presented in this work computes switching angles without using complex algorithms and/or by solving non-linear equations. Hence, the generalized numerical series method gives an easy implementation of multilevel inverters with large number of levels.

The quality of the multilevel inverter (MLI) output voltage depends on the instants of level shifting in a cycle of AC output waveform. These instances are called switching angles. In this paper, a new method for switching angle calculation is suggested for symmetric multilevel inverters. The proposed method is derived based on superposition of square and sinusoidal waveforms and is applicable to multilevel inverters with odd number of levels in output. In the proposed method the switching angles are expressed as a function of the level height, for unit amplitude output AC staircase waveform. It is found that for a fixed number of levels in output AC waveform, there are limits on the range of the level height. Further, it is observed that the values of total harmonic distortion, harmonic components, and fundamental voltage depend on the level height. The variation of each of the above parameters with the full range of the level height for three, five, and seven level output AC voltage is obtained numerically and presented here. These results are applicable for any number of odd levels in output AC voltage, and are useful in optimizing the output voltage quality of multilevel inverters.

The auto-transformer differs from a two winding transformer, in that the power is transferred from primary to secondary inductively as well as by conduction because there is a direct electrical connection between the primary and secondary windings of an auto-transformer. This is unlike a two winding transformer where the primary and secondary windings are electrically isolated. Therefore, the mathematical model for two winding transformer cannot be simply extended, with little modifications, to use for an auto-transformer. In the literature survey, the mathematical models of an auto-transformer are found to be application specific, which suggests that there is a scope for deriving a general mathematical model for the same. In this paper, a mathematical model of auto-transformer is derived, and it is solved numerically to obtain insights into the dynamics of the auto-transformer system. In an auto-transformer, the wiper position is an additional input to the system along with the input applied voltage. Simulations are carried out to see the autotransformer operation when it is supplying lagging and leading power factor loads, and when the wiper position is changing gradually after the initial turn-on transients are over. Also, the operation is shown when the input voltage is a step function. It is found that the model gives satisfactory results which are verified from the steady-state relations derived from the phasor diagram obtained for the steady-state operation.

This paper presents a new optimized distributed winding scheme for space harmonic reduction in the magneto-motive force. The objective of the optimization focuses on reducing lower-order dominant harmonics while maintaining the tooth width constant to limit the teeth saturation. As in the case of the wound rotor induction motor, both the stator and rotor, consist of distributed winding, therefore, the optimization has been applied on both windings so that the air gap flux would have the lowest harmonic content. The winding function analysis has been applied to evaluate the harmonic contents in the winding distribution and to analyze its overall effect on airgap magneto-motive force. Further, the machine performance has been analyzed and compared for both the new optimized winding and conventional winding using the time-stepping Finite Element Method.

In this paper, a cubic spline guidance law is proposed for intercepting a stationary target at a desired impact angle in surface-to-surface engagement scenarios. An inverse method is used, which represents the altitude as a cubic polynomial of the downrange. The paper addresses many shortcomings of earlier work in this area. In particular, an explicit guidance expression is derived, which makes the guidance law effective and accurate in the presence of disturbances and uncertainties. It is also shown that the guidance command can be obtained using a single cubic spline polynomial even for impact angles greater than and equal to $\pi / 2$ , while resulting in substantial improvement in terms of lateral acceleration and length of the trajectory. The paper also obtains an analytically derived capture region. The proposed guidance law is conceptually simple, independent of time-to-go, computationally inexpensive, and does not need linearization.

Background: Audit is one mechanism for evaluating the effectiveness of the total quality system. Transfusion medicine or blood bank audit embraces all procedures from blood procurement to the long term consequences of transfusion. Aims and Objectives To understand the problems arising in day to day working of blood bank and to ensure the appropriate indication for issuing blood and blood components to different departments. Materials and methods Present audit of blood bank is retrospective study done for a year in tertiary care center in central region of India. Data collection of donors and whole blood issue is done for one year from 1st January 2016 to 31st December 2016. Component separation had started from August 2016, so audit of component separation and its usage has been done for one year from 1stAugust 2016 to 31stJuly 2017. Results In year 2016, total blood units collected were 6131 and issued were 5897. Majority of blood issue was to surgical wards 3790 compared to non-surgical wards 2107. Out of 6109, 203 were positive for transfusion transmitted infections (TTI). 20 transfusion reactions were reported in 2016. From 1st August 2016 to 31st July 2017, total 1060 Packed Red Cells (PRC) were prepared and 1009 were utilized , 1120 units of FFP were prepared, out of which 778 were utilized and 817 platelet concentrates were prepared but only 205 is utilized. Conclusion Results obtained from these types of retrospective studies will provide opportunity for finding strategies in improving the blood bank services.

This paper presents the implementation of fractional order PID (FO-PID) controller using hardwired modules of constant phase element (CPE). A new approach of phase shaping by slope cancellation of asymptotic phase plots for zeros and poles within the given bandwidth is realized. Analog circuits, which exhibit analog fractional-order integrator and fractional-order differentiator, are used for building the FO-PID controller. The design procedure is developed to obtain the optimal pole---zero pairs and respective "Fractance" components to realize for any value of fractional differ-integrator. These CPE elements give minimum error tolerance over the set phase value by using commercially available (R---C) components and Op-Amps. The pole---zero location in the root locus plot with constant asymptotic angle under various feed-forward gains is achieved with these analog integrodifferential circuits of the FO-PID. The iso-damping feature of the controller is practically demonstrated. A comparative performance is demonstrated under various settings of feed forward gains, which indicate the constant overshoot with FO-PID against the conventional PID. These circuits are developed and implemented with a DC motor emulator to confirm the designed performance of the controller.

IntroductionIn India, glaucoma is the third most common cause of blindness, reflecting both its asymptomatic presentation and a lack of knowledge in the general population. No previous published data of glaucoma awareness among the Indian Armed forces personnel exists, who constitute a unique group consisting of people drawn from all parts of the country and society.MethodsBilingual questionnaires were distributed to 496 serving Army, Navy and Air Force personnel serving in units local to the Zonal military hospital in North India. Having heard of the term glaucoma resulted in the subject being ‘glaucoma aware’, while ‘knowledge of glaucoma’ required at least three out of six questions to be answered correctly.Results110/496 (22%) participants were found to be glaucoma aware, while knowledge of glaucoma was found in 60/496 (12%) participants.ConclusionsThis study demonstrates that glaucoma awareness and knowledge is high compared with rural or urban Indian populations. This is likely reflects the frequent health camps conducted by the armed forces and periodic medical examinations. However, these figures are still low compared with developed countries and likely reflects differences in education standards, socioeconomic status and differing influences of the media.

Multilevel inverters have become more popular in the recent years for high power-medium voltage applications. Multilevel inverter performance is high compared to the conventional two level inverters due to their reduced harmonic distortion and lower electromagnetic interference. However, the main drawbacks of conventional multilevel inverters are increased number of switches, complex pulse width modulation control and balancing of capacitor voltages. In this paper, a generalized topology for single phase asymmetrical multilevel inverter has been proposed. This generalized topology is optimized to reduce number of switches and to minimize number of switchings per cycle. The optimized topologies have been proposed for five, seven and nine level inverters and a switching strategy is proposed to determine optimum switching angles which give lowest THD at fundamental switching.

In this paper, an approach for reducing the torque ripple in a two phase unsymmetrical induction motor is analyzed. A single phase induction motor is basically a two phase induction motor and generally, the windings on the stator are not identical. Hence, it is called unsymmetrical two phase induction motor. If an unsymmetrical motor is supplied by two phase balanced supply voltages then the ripples in the electromagnetic torque are unavoidable. However, if the supply voltages are made unbalance to counter the unbalance in the windings the torque ripple can be reduced. The mathematical model of the machine in stator attached reference frame is used to derive the torque expression in terms of stator currents. The torque expression consists of a constant term and a pulsating term. These terms used together unable finding the conditions on stator currents and hence stator voltages so that the ripples in the torque produced can be mitigated.

This paper presents a modification in the conventional multi-phase distributed winding to reduce the space harmonics in the distribution of magneto-motive force (MMF) around the air-gap periphery. The technique used for modification in winding distribution includes the optimization of conductors per slots and the slot swapping in each phase. This method effectively reduces the dominant lower order harmonics, however, the number of harmonics reduced depends on the slots per pole per phase in the machine. The winding function approach is used to get the closed form expression of Fourier expansion of space MMF distribution. An example of 36 slot, 2 pole induction motor with both conventional single layer distributed winding (SLDW) and modified distributed winding (MDW), is used to compare the performance. The time-stepping Finite Element method is used to analyze the dynamic performance of the induction motor using the proposed winding scheme.

In this paper the performance of single phase two winding transformers is analyzed when excited by a voltage produced by superposition of square and sine wave and supplying different kind of loads. The transformer is excited in this manner to increase its voltage rating which results in power capacity enhancement. A study is carried out to access the response of two different class of transformers, small transformer (1 KVA) and distribution transformer (25 KVA) with different loads, for above said input. The effect of above said excitation on magnetizing current, load voltage, and load current is analyzed and compared with sine wave excitation. To access the effectiveness of this power capacity enhancement method, numerical simulations are carried out and the empirical results are presented.