One of the chemical compounds that have multiferroic properties is BiFeO3. The multiferroic properties of the material would be better if the material has good magnetic properties as well. To obtain a high magnetic properties, the engineering process is carried out to synthesis BiFe1-xZnxO3 (x = 0.1 and 0.07) by doping Zn into BiFeO3 compound. Engineering process performed by sol-gel method. Calcinations in sol-gel method is carried out at a temperature of 150 and 175oC for 4 hours and the sintering process at a temperature of 650oC for 2, 4 and 6 hours. Characterization of the powder is modified done by using TGA / DTA test, X-Ray Diffraction (XRD) test and magnetic properties (Vibrating Sample Magnetometer) test. From the results of TGA / DTA test, it could be seen that the calcinations process could be performed at temperatures of 150 and 175oC and sintering process could be carried out at a temperature of 650oC. From the result of XRD test, it is shown that the powder of BiFe0.93Zn0.07O3 has minimum impurities (bismite 2.9% and iron 3.6%) at calcinations temperature of 175oC for 4 hours and sintering at 650oC for 6 hours. But the most excellent magnetic properties belongs to powder of BiFe0.9Zn0.1O3 with the value of magnetic polarization saturation of 0.65 emu/gram, while the value of magnetic polarization saturation for BiFe0.93Zn0.07O3 is 0/45 emu/gram.

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In processing of grain material with a high probability a favorable environment for infection is created that promotes deterioration in properties and qualities of production which of him is made. Monitoring of one of the districts of Russia has been carried out. The analysis of various directions of application of HFEF grain processing of materials has been carried out. The developed technological process is based a combination of microwave heating with barothermal moisture-heat treatment.

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To examine the influence of trivalent dysprosium ion (Dy³⁺) on physical and optical properties prepared by melt quenching method. The samples composition of 20CaSO₄ (80 - x) P₂O₅ – xDy₂O₃, where x = 0.1, 0.2, 0.3, 0.4 and 0.5mol% were prepared and analyzed. Materials were characterized by X-ray diffraction, UV visible and photoluminescence spectroscopy, amorphous nature of the samples was confirmed by X-ray diffraction technique, UV-Vis for optical measurement and luminescence for excited state dynamics. The UV absorption spectra of the glass sample correspond to ⁶H_11/2 (1673 nm), ⁶H_9/2 (1262 nm), ⁶F_9/2(1087 nm), ⁶H_5/2 (899 nm), ⁶F_5/2 (796 nm), ⁶F_3/2 (753 nm), ⁶G_11/2 (422), ⁴I_13/2 (384) and ⁶P_7/2 (347).The physical properties comprise of glass density, molar average molar volume, ion concentration, dielectric constant and molar refractive index was determined. The band gap (Eopt), Urbach energies (?E) and refractive index lie in range and decreases with increase in Dy³⁺ concentration. Therefore, Dy³⁺ compositional changes were examined and indicate that dysprosium phosphor could serves as a potential candidate for optical application as laser is included.

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As the fossil resources are at risk of extinction, many efforts are being introduced to produce electrical energy. Micro-electrification by utilizing the energy from vibration has become an alternative way to generate electricity. It is through a device with sub-micron-scale dimension sub-micron-scale dimension. This work focus to generate electricity with the utilization of the off-the-shelf piezoelectric transducers; Polyvinylidene Fluoride (PVDF) and Lead Zirconate Titanate (PZT) under different rain shower density. With the three different flow rate of an artificial rain shower, it is able to generate maximum power of 2.4x10-6Watt and 27x10-6Watt for PVDF and PZT, respectively. However, the energy is significantly influenced by the rectifier circuit. This paper presents the performance of the power generation from raindrop using piezoelectric transducers available in the open market.

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The present paper details an experimental investigation on heat transfer and friction factor characteristics of solar air heater roughened with V rib with symmetrical gap and staggered rib. The roughness has fixed value of relative roughness pitch (P/e) 12, relative staggered rib pitch (P’/P) 0.65, relative gap width (g/e) 4, number of gaps on each side of V rib (Ng) as 3 and angle of attack (a) 60o. The relative staggered rib size (w/g) varied from 0.5 to 2 and the variation in Reynolds number is from 3000 to 14000. The enhancement in Nusselt number and friction factor over smooth surface under similar operating and flow condition has been observed. The highest thermo hydraulic performance of roughened solar air heater having V-rib with symmetrical gap and staggered rib is found for relative staggered rib size (w) is equal to the gap width (g).

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In this paper, a finite element method involving Petrov-Galerkin method with quartic B-Splines as basis functions and quintic B-Splines as weight functions has been developed to solve a general sixth order boundary value problem with a particular case of boundary conditions. The basis functions are redefined into a new set of basis functions which vanish on the boundary where the Dirichlet and Neumann or mixed types of boundary conditions are prescribed. The weight functions are also redefined into a new set of weight functions which in number match with the number of redefined basis functions. The proposed method was applied to solve several examples of sixth order linear and nonlinear boundary value problems. The obtained numerical results were found to be in good agreement with the exact solutions available in the literature.

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Groundwater is a standout amongst the most significant natural assets, which supports human health, economic development and ecological diversity. Overexploitation and unabated contamination of this indispensable asset are undermining our biological systems and even the life of who and what is to come the present review to investigate groundwater potential at different regions in Palani Taluk, Tamil Nadu, India. To decide the resistivity and thickness of the distinctive layers, Schlumberger Vertical Electrical Sounding review (VES) was done in 27 arbitrarily chose areas, where groundwater assumes a fundamental part in farming, local and modern district. The ground information was translated by IPI2WIN programming software to break down the resistivity and thickness of first and second layer fracture regions of the diverse layers. Consequences of the geophysical strategy were utilized to plan spatial distribution map by IDW tool device in GIS programming. By utilizing GIS (Geographical Information System) and RS (Remote Sensing) strategies standard methodology was proposed to recognize Groundwater potential region in Palani Taluk. The map was generated via GIS tools like IDW, overlay & etc. To obtain accurate results following parameters need to be considered such as slope, geology, drainage density, geomorphology along with lineament density map are generated by using Survey of India toposheets (SOI) of scale 1:50000 and satellite data. It is then coordinated with weighted overlay in ArcGIS and reasonable rank was alloted for every parameter. For instance, different parameters of topography units, weight components are chosen based on their ability to store groundwater. This methodology is rehashed for every single other layer and resultant layers are reclassified. Groundwater potential regions are grouped into four classifications from very poor to excellent in the review range. We have to superpose output map, groundwater potential region district distinguished by the geophysical method and groundwater potential region recognized by GIS and Remote Sensing. The resultant map gives us most favorable locations which are identified by low resistivity and more thickness (geophysical method) within areas comes under the good and excellent region of groundwater potential region (GIS & Remote sensing) in the review region. Accurate location can be identified in the study region, which helps to construct suitable recharge region structure to improve the groundwater level.

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With the fast development of modern communication techniques, the demand for reliable high data rate transmission is increased significantly. Different modulation techniques allow researchers to send different bits per symbol achieving different and higher throughputs or efficiencies. Because of its efficiency in power and bandwidth, M-ary Quadrature Amplitude Modulation (M-QAM) is one of widely used modulation techniques in the practice. Therefore, a need of studying and evaluating the performance of QAM modulation schemes is an important task for designers. In this paper, M-QAM modulation schemes for even number of bits per symbol (32- and 128-QAM) and for odd number of bits per symbol (16- and 64-QAM), over Additive White Gaussian Noise (AWGN) channel, are studied. A Simulink-based simulation model for M-ary QAM is designed. Theoretical and simulation results for Bit Error Ratio (BER) performance of QAM modulation schemes are obtained using Matlab/Simulink and Matlab/BERTool. The results are evaluated and compared.

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In this paper, a new and compact microstrip narrow-band bandpass filter using multilayer technology is proposed for WiMAX Applications. The new filter structure consists of four spiral resonators placed on two stacked layers where the metallic ground plane is deposited onto the bottom surface of the dielectric. Compared to conventional microstrip filters, the proposed multilayer structure provides a significant size reduction by halving about 50% the whole filter size. It was designed, simulated, fabricated and tested. There are good agreements observed between the simulated and measured results. The proposed multilayer filter is aimed to simply integrate into and perform better within any circuit design of microwave applications present communication systems always demand at lower cost.

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Due to its geographic location, Colombia has a great potential for the development of multiple fish farming; this paper describes the development of a programmable system which consist of the automation of the fish breeding process. The developed prototype is formed by a mechanical part allowing the storage and provides the exact amount of food in a safe way through a design of a rotary cylinder with a cavity for dispensing the food volume. The electronic component has oxygen and temperature sensors, an electronic control unit based on PSOC embedded systems, supported by a MESH topology Zigbee telecommunications infrastructure, allowing establishing a direct transfer of the information to a graphic interface (Software) developed using Python. All of the elements of the prototype make it a diagnosis tool which allows the farmer to evaluate the production methods for an accurate and opportune decisions making, obtaining as a result the resources optimization, improving the wellness, the farmers life quality and their families by increasing the crops profitability.

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This paper investigates numerically the performance and emission characteristics of Soy Methyl Esther (SME) in a diesel engine. A single-cylinder, four strokes, naturally aspirated and direct injection compression ignition engine was fueled by a mixture of SME and pure diesel fuel, forming 4 blends: pure Diesel (D100), 20%SME+80%, diesel(B20), 40%SME+60%diesel(B40) and 100%SME(B100). The computation was made via the full-cycle engine simulation software Diesel-KR. The model set was first validated against experimental results from literature with pure Diesel. Performance and emission characteristics at different loads and constant speed were then compared to conclude which percentage is more suitable for the engine, in term of efficiency and pollution emissions. In this study, it is found that B20 offers similar results in term of consumption and pollutants emission. Thus, the engine could run with the B20 blend, giving similar performance than pure diesel. The investigation goes on to see the effect of an engine modification, namely retarding the start of injection on the engine performance when the B20 is used. It was found that retarding the start of injection leads to lower fuel consumption, ignition delay and combustion duration, which improves the thermal efficiency of the engine. For the NOx emissions, the retarded start of injection lowers the NOx emissions, yet increases the PM emissions by as much as 62%.

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Increasing economic growth and population can improve the energy demand in all sectors, and give impact on the depletion of oil reserves. The effort to overcome this problem is increasing the production of biofuels. Biofuel is a fuel derived from vegetable oil, one of them is palm oil. Biofuel can be produced by a catalytic cracking method. In this research, we use Zn/HZSM-5 as bio-fuels catalyst. The purposes of this study are to determine the process of making Zn/HZSM-5 catalyst, determine the effect of temperature on bio-fuel producing and determine the influence of catalyst regeneration on bio- fuels yield. The method of this research was created HZSM-5 catalyst synthesis using Plank method and then impregnated with ZnSO4.7H2O to obtain Zn/HZSM-5 catalyst. Zn/HZSM-5 catalyst was made with various concentrations of Zn 2%, 3%, 4%, 5% and 6%. Then it was used to produce bio-fuel with a variation of Zn concentration and variation of temperature. The best result was obtained at 4% Zn concentration which has 23.97% yield of biodiesel, 2.54% yield of bio-gasoline and 1.67% yield of bio-kerosene. By increasing the operating temperature, can increase the yield of biofuels. But by regenerating the catalyst, yield of biofuel became decreased due to the active site reduction of the catalyst.

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It is important to highlight the use of the technologies and highlight the work of IoT, since it is not allowed to send the machine-to-machine. For communication in an emergency environment, IoT stands out for being considered as a strong technology. The emergency alert service offered by Terrestrial Digital Multimedia Broadcasting (TDMB) is known as the Alarm Service, but it is automatic emergency alert services (AEAS). This document a methane sensor circuit with Wi-Fi connection is designed with an ATMega microcontroller for the implementation of the IoT. It’s intended to illustrate a consumer transceiver for IoT's long-range communications in emergency environments. In order to overcome the drawbacks of AEAS, the signaling method can be used for the system which is proposed an embodiment. This IEEE802.11ah Wi-Fi protocol works as a transceiver, and is under standardization at a very low cost and not only that, also with low power services.

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The extensive growth of industrial demand and domestic demand will make the power system more expensive. The increase of demands will also leads to the increase of the losses from generation to the distribution level. To achieve the flexible operation of the power system from generation to the distribution along with the exponential growth of load, Flexible alternating currents transmission system (FACTS) devices are used. The inclusion of FACTS devices in the power system will make the system more reliable. With the advancements in the power electronic devices the design of facts devices will also take more advantageous position to operate the power system with more reliable. There are many types of FACTS devices such as series, shunt, series-shunt and shunt-shunt among these types shunt –shunt FACTS device plays a major role to operate the power system with less power losses and improved voltage profile. Unified power flow controller (UPFC) is one of the types of shunt-shunt FACTS device. In this paper the incorporation of UPFC within the power system which improves the voltage profile and reducing the losses. The placement of FACTS devices and size of the FACTS device is through analytical and soft computing techniques which are Genetic algorithm (GA), particle swarm optimization (PSO) are used.

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O. rhinoceros is a major pest of coconut palm in Indonesia. The research aims to study the ecology of the density and composition of the stadia Oryctes rhinoceros in field. The study location was determined by purposive sampling method. The observed locations were the goat and cattle manure piles, garbage piles, rotten coconut trunks, and sawmills. The insects in these sites were recorded on its number and stadia (egg-larva (grub) -pupa-imago). Then, the population density and the stadia composition were calculated. To caoture adult of O. rhinocerosbeetle observed by using pheromone, called ferotrap. The larval breeding sites were found in 26 locations. The densities of O. rhinoceros in the breeding site were 0.2-3.7 head/ind/m2. Total of O. rhinoceros were 460, consisting of eggs (5.43%), 1st instar (4.78%), 2nd instar (14.13%), 3rd instar (72.39%), and pupae (1.73%) and imago (1.52%). The most abundant composition found in the habitat was the larval stage of O. rhinoceros especially the instar 3 larvae. There were 217 O. rhinoceros and 59 Rhynchophorussp captured for 12 weeks. The benefit of this research is to predict the exact time when the insects will turn into imago and attack the coconut plantations. Therefore, it can be useful for proper control strategies.

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This paper presents a method of constructing orthogonal binary sequences with any positive even integer lengths. We show that periodic binary signals, coded in accordance with these orthogonal binary sequences, contain groups of signals with zero cross correlation. It is possible to construct an ensemble of binary signals with zero cross correlation properties by using only one coded signal from each of these groups. When the ensemble of binary signals is transmitted through one communication channel, they do not interfere with each other and can be separated on the receiver side without tight synchronization. The results of this paper can be used in asynchronous CDMA communication, telemetric networks (e.g. Wireless Body Area Networks (WBAN), Wireless Sensor Networks (WSN)) and optical systems.

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Traditional gold mining activity is one of the source of mercury contamination. Total mercury concentration around the tailing ponds in Kulon Progo ranged from 0.30 to 22.51 mg/kg, which the exceeded the quality standard values set by the government of Indonesia No. 101 of 2014 which is 0.3 mg/kg. One method that can be applied is stabilization/solidification (S/S). This study aims to determine the optimum composition of Portland cement and tras soil used in S/S with contaminated soil. The study at first step, Portland cement and tras soil compositions was used by variations of the weight value of 100: 0, 90:10, 80:20, 70:30, 60:40, 50:50, 40:60, 30:70, 20:80, and 10:90. At second step, contaminated-soil samples were added into optimum from first step, with a variation composition of binder: soil are 50:50, 40:60, 30:70, 20:80, and 10:90. Toxicity Characteristic Leaching Procedure was applied based on US EPA method 1311. First test result in optimum composition of Portland cement: tras soil (10:90), with the compressive test value of 96 kg/cm2. The second result of compressive test values of binder: contaminated soil (10:90) was 6 kg/cm2 is with mercury concentrations in the TCLP test of 0.0011 mg/L. The result of compressive test met the quality standards of US EPA for the management of contaminated soil at 3.5 kg/cm2. The result of TCLP test met the quality standards for products of S/S in accordance with Government Regulation 101 Year 2014 at 0.05 mg/L.

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This paper presents the investigation of performance in inverters and induction motor with fault condition when the system is framed as two parallel inverters feeding a single induction motor. The two inverters share the total load current drawn by induction motor such that the rating of power devices used in inverters gets reduced. Diode clamped multi-level inverter consists of power switches and switch faults takes place very often due to many reasons in circuit behavior. Diode clamped inverter is controlled using asymmetrical PWM technique. Presence of open type of switch fault makes inverter malfunction and might cause load characteristics to disturb. Examination was carried out in this paper for line currents, line voltages and phase voltages of both parallel placed inverters along with characteristics of induction motor with fault in inverter switch. Proposed work was carried out using MATLAB/SIMULINK software and results were presented.

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Leading edge of the gas turbine blades is subjected to highest temperature. Jet impingement cooling is an efficient technique for leading edge blade cooling. In this present study, a single baseline cylindrical hole and the proposed converging conical hole is numerically investigated for convective heat transfer using CFD code, STAR CCM+. The converging angle of the conical hole is 20°and the ratio of diameter is equal to two. The hole diameter is 2.15 cm and the study is carried out at Reynolds number ranging from 11000 to 50000 for a jet impinging length of R/2. The target surface is maintained at constant heat flux of 10000 W/m2.Steady-state simulations are performed using Reynolds Averaged Navier Stokes equation along with k?-SST turbulence model for closure. Based on the Nusselt number and temperature distribution, converging conical hole is observed to give a better heat transfer thereby cooling the blades effectively. Around 186 % increase in Nu and 13% decrease in surface temperature of the concave surface is observed at jet impingement point for Re = 23000.

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Fluid and litho logy separation process is an essential stage in term of reservoir characterization which is used to map hydrocarbon distribution. However, such process is sometimes not applicable if it relies merely on conventional seismic attributes. That is why, the introduction to term, Poisson Impedance (PI), could be an effective way to cope with this issue. PI attributes which were used as an indicator, needing Acoustic Impedance (AI) and Shear Impedance (SI) as well as c factor (rotation optimization factor). The optimum c factor was obtained through TCCA method (Target Correlation Coefficient Analysis). In this study, it had been conducted a sensitivity test in term of separating litho logy and fluid at three wells in ‘WA’ Field, South Sumatra Basin. Moreover, PI attributes modeling was done using simultaneous AVO inversion to extract AI and SI. The modeling result showed that gas saturated sandstone would be well separated from brine in low FI value, below -1000 ft/s*g/cc (-3.05*105 kg/m2s). Low FI anomaly at all modeling wells proved that all wells reviewed were gas wells distributed towards south-east. Fluid impedance was then used to image gas distribution.. On the other hand, AVO analysis was conducted in order to know the sensitivity of the existing seismic data on the presence of anomaly.

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The existing methods of the grains thresh possess a number of shortcomings that leads to a harvest shortage. The new way of the pneumatic threshes with elements of aero-technologies and acoustic vibrations was developed and tested. Efficiency of this method is confirmed by experimental studies. The economically reasonable technological process of impact on ear jet streams of air has been developed.

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The use of titanium as a cathode in the anodizing process AA 6061 proved to increase the mechanical strength and corrosion resistance. The surface morphology is tested by using scanning electron microscopy (SEM) and then the surface composition is tested by using Energy Dispersive X-ray (EDX). Hardness is tested using microvickers hardness tester the results showed that the increase in hardness after anodizing, while the porosity decreases with the increase of potential.

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An effective cryptographic algorithm plays a major role in secure communications which is important for today’s digital world. Network security primarily depends upon Cryptographic algorithms as its applications are. The main goal of a cryptographic algorithm is to satisfy four conditions which are Integrity, Confidentiality, Authentication and Nonrepudiation. Though there are numerous algorithms there is a chance of drudge caused due to adversaries and hence for the better security we in this paper considered few existing algorithms and on few modification we compared them through their performance level on considering few factors like encryption time, throughput, computational time and memory usage. We also added a new concept related to steganography in this paper where that technique is evaluated based on histogram level. The proposed algorithm is effective for secure communications in this digital era. In this study is made particularly for the evaluation of comparison and performances of cryptographic algorithms.

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Metal injection molding (MIM) is preferred choice for mass production of intricate and complex parts. However, machining of intricate and complex mold for low volume of part production could be very time consuming, skill intensive and expensive. For low volume requirement of MIM parts, typically for prototyping, design validation and visual inspection, mold experiences small number of MIM cycles and once demand is met, mold is rendered useless. Contrary to traditional machining, polymer molds made through additive manufacturing (AM) process, called Rapid Tooling (RT), could comparatively be a swift and economic approach. For low to medium number of MIM cycles, 3D printed polymer molds could potentially yield performance, comparable with machined metal mold. Present study investigates enhancement of various approaches for 3D printed polymer molds for their potential use in MIM. Consequently, 3D printed polymer molds proved promising for prototype and low volume manufacturing of MIM parts.

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An attempt has been made in doing a comparative study on characterization and effect of nano silica and micro silica on the mechanical and durability properties of High Performance Concrete (HPC). The obtained test results on addition of nano silica and micro silica displayed that the compressive strength, tensile strength of HPC was enhanced upon the addition of nano silica and was comparatively higher than micro silica. In the case of opposition against capillary intake, water absorption, voids and volume of permeable pores, concrete with nano silica performed well compared to micro silica. Microstructure examination was achieved using Scanning Electron Microscope (SEM). SEM studies indicated that the microstructure of concrete was improved by uniform distribution of nano silica particles. The proportion of voids existing in case of nano silica is fairly lesser than of micro silica.

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Overall Equipment Effectiveness (OEE) is commonly used as a scale in industry to indicate the effectiveness of the machine or process. Although it is just a multiplication of three criteria, availability, performance and quality rate, but it reflects the actual situation of the machine or process. OEE is one of the important elements in continuous improvement plan to assist operation team to indicate the scope of improvements. Therefore, it is important to track out all the wastes available in the calculation. However, it is not an easy task to track out wastes correctly. Although six big losses are mentioned in the OEE philosophy but there are wastes that hidden in the OEE percentages and tend to ignored by operation team. This is the obstacle for industry to achieve optimum OEE level. Therefore, the available of hidden wastes should be visualise and easy to detect. Maynard’s Operation Sequence Technique (MOST) is the suitable tool to quantify the hidden wastes in the OEE calculation since hidden wastes are referring to human interaction, movement or action. MOST is a work measurement tool that used to evaluate the manpower performance. Through MOST, a list of work standard can be constructed and used to compare with the hidden wastes. Then, a modified OEE calculation method is developed to enhance traditional OEE calculation in term of visualization of hidden wastes.

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The High voltage high frequency (HVHF) oscillations caused by the power electronics and non-linear loads, such as converter transformers, arc furnaces, welding machines, photocopiers, microwave ovens, etc, can pollute the supply voltage by generating the high frequency oscillations thereby causing surface discharge formation on the insulation of transformer. This work deals with the effect of high frequency oscillations in the surface discharge formation on oil impregnated pressboard used in the converter transformer. Converter transformers are a part of transmission system located near the converter station, where the occurrence of high frequency oscillations is high due to the presence of power electronic devices in it. These high frequency oscillations, if enters into converter transformer, can cause formation of surface discharges on the insulation, which is one the major causes for failure of transformer. The insulation materials in converter transformers are mainly oil impregnated pressboard and mineral oil. During operation, the oil/pressboard structure undergoes multi stress ageing which results in surface discharge activity and cause gradual physical and chemical degradation. Surface discharge activity at the oil impregnated pressboard interface is studied by conducting tracking studies with high frequencies such as 85KHz and 113 KHz and observed the surface degradation due to tracking. After the test, it is concluded that the tracking paths are formed due to surface discharges, which can produce degradation by-products which contaminate and degrade the transformer oil. The current and voltage patterns formed during the surface discharge process under tracking studies are recorded. Degraded zone of oil impregnated pressboard insulation due to surface discharges was analyzed using Attenuated Total Reflectance Fourier Transform Infra-red (ATR-FTIR) spectroscopy, which can provide a specific wavelength spectrum of any functional group formed due to characteristic changes that occur due to ageing. The tracking study and pressboard material characterization at the tracked zone give a clear inference about the byproduct formation and degradation mechanism of converter transformer insulation system.

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A clean, source free and environmentally friendly alternate source of energy such as wind energy can be use for providing sustainable power supply to remedied an epileptic and unreliable power supply systems. This paper carried out an analysis of wind speed data at Mallam Aminu Kano International Airport in Nigeria using Weibull distribution methods to determine the wind features and its potentials necessary for power supply generation. Weibull parameter methods have been chosen for this analysis because of its efficiency. A six years (2009-2014) monthly mean wind speed data measured at 10 m height was collected and extrapolated to 100 m height level for statistical analysis. The average wind speed, standard deviation, Weibull scale and shape parameters has been analyzed for both 10 m and 100 m height levels. The minimum average wind speed was found to be 5m/s and the maximum average wind speed was 12.5 m/s at the 10 m height level, the Weibull scale parameters were found generally higher than the shape parameters. The Weibull parameter models were validated by RMSE. The site has been found to have great potentials for utility power generation capacity.

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In this project an information system was implemented to optimize the process of conducting the thyroid profile tests in Huila hospitals in order to improve the organization of the results, making access to the results much more comfortable and efficient. The HL7 standard set was used as a guide for good interoperability and to make the system scalable. Access can be made through any web browser or any device due to a responsive web design was used. The information system allows access to the data of a specific patient and it is possible to export information from the database to obtain different statistics.

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Efficient underwater acoustic communication and target locating systems require detailed study of acoustic wave propagation in the sea. Many investigators have studied the absorption of acoustic waves in ocean water and formulated empirical equations such as Thorp’s formula, Schulkin and Marsh model and Fisher and Simmons formula. The Fisher and Simmons formula found the effect associated with the relaxation of boric acid on absorption and provided a more detailed form of absorption coefficient which varies with frequency. However, no simulation model has made for the underwater acoustic propagation using these models. This paper reports the comparative study of acoustic wave absorption carried out by means of modeling in MATLAB. The results of simulation have been evaluated using measured data collected at Desaru beach on the eastern shore of Johor in Malaysia. The model has been used to determine sound absorption for given values of depth (D), salinity (S), temperature (T), pH, and acoustic wave transmitter frequency (f). From the results a suitable range, depth and frequency can be found to obtain best propagation link with low absorption loss.

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At present, the problem of timely examination of overhead transmission lines is acute. To solve it, devices with the ability to organize wireless data transmission without binding to transmitting stations were developed, including a set of sensors for measuring the parameters of diagnosed high voltage transmission lines. The use of modern electronic technologies and power schemes ensures the autonomy of the device, since it does not depend on external power sources, but makes power take-off directly from the line. Wireless data transmission is carried out with the help of the wireless network for process automation (WNPA) modules. Such a communication channel allows organizing not only inexpensive, but also capable of self-recovery network. The method of monitoring ice coating on overhead lines based on the mathematical model of chain line is considered. It allows identifying the current sag and elongation of the wire in a span, the force of its tension, taking into account the misalignment of wires on the line, based on the data obtained from wireless sensors.

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In the process of data communications, although data has been encrypted, there is the possibility of such data can be known by others. One possibility is that the person intercepts the communication medium used by the two individuals who are communicating. This technique called man-in-the-middle-attack. This research provides a step-by-step procedure for securing messages from man-in-the-middle-attack attacks with interlock protocols where the process of sending messages is encrypted using the RSA algorithm, and test results show that the use of interlock protocols can overcome man-in-the-middle-attack.

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This paper presents the design, analysis and impact behavior of magnesium alloy automotive wheels by finite element method. A new combination of alloy materials is attempted to improve the quality and service life of the wheel rim with less fatigue and reduced cost. Magnesium alloy (Zk60A) combination is selected for this work and wheel rim is designed using the Solidworks modelling software. The structural analysis of wheel rim is carried out using ANSYS software and the results are compared with that of the steel alloy. It is found that the Zk60A magnesium alloy results in lighter wheel and enjoys associated benefits like reduced stress, better mileage, improved service life, etc. With this encouraging result, the Zk60A magnesium alloy wheel will provide a better alternate to the existing materials.

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The present paper deals with the stability analysis of a three species ecological model with mutualism, neutralism and prey-predation. Here the second species is a predator preying on the first species and the third species is mutual to the first and neutral to the second species. In addition to the interaction among the species which helps in their respective growth rates, the species are provided with an alternate food resource. Also a more symmetric form of time delay is assumed in the interaction between the predator and the prey species. The model is governed by a system of integro-differential equations. Using Routh-Hurwitz criterion the local stability is established at the interior equilibrium point and a Lyapunov function is constructed to study the global asymptotic stability of the system. Some valid conclusions regarding the sustainability of the system are made at the end using numerical simulation.

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A half-scale single-bay two-storey RC frame was designed in accordance to Eurocode 8 and constructed using ready mix-concrete by considering seismic load with Ductility Class Medium (DCM). The two-storey moment resistant RC frame was constructed by preparing reinforcement bars caging, preparation of formwork, concreting and curing process. Then, the specimen was tested under in-plane lateral cyclic loading using a double actuator starting from ±0.01% until ±2.25% with incremental of 0.25% drift. The total number of twenty-four cycles of drift was imposed to RC frame under control displacement method. The visual observations showed that a lot of cracks were concentrated at the corner and exterior beam-column joints where these were the points of transferred the load from top to the bottom of the structure. The ultimate lateral load of 158.48 kN in pushing direction and -126.09 kN in pulling direction was recorded at 2.25% drift. Based on the experimental result, elastic stiffness is 4.04kN/mm, secant stiffness is 1.14kN/mm, effective stiffness is 2.06kN/mm and ductility is 3.51. It can be concluded that the RC moment resistance frame able to withstand minor to moderate earthquake because the value of ductility is ranging between 3 to 6.

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In the era of environmental consciousness, the relevance of naturally occurring materials are gaining more and more importance in the development of new material for engineering applications. In this context a natural fiber like sisal has a lot potential as reinforcement in engineering composites as an alternative to harmful, expensive synthetic fibers. The objective of this work is to develop an elastomer composite using only naturally occurring materials. A Natural Rubber- 40% v/v sisal fiber composites with the sisal fiber given four surface modifications were made & two additional samples with addition of 10% w/w activated coconut shell powder is also made for evaluating the influence of filler powder in the composites. A total of six samples were made and are evaluated for their mechanical properties like Tensile strength& tear strength. An increase of 73% tensile strength obtained for alkalized impregnated sisal fiber composite with respect to Natural Rubber. Tear strength showed exceptional increase up to 246% for alkalized impregnated sisal fiber. Hardness values increased to 200-228% range for the composites. The best abrasion resistance is shown by alkalized impregnated fiber. Compressive strength is maximum for raw fiber and coconut shell powder filled rubber composite.

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The ability to precisely determine geographic location information is crucial for many navigation and location systems including in oil mining industry. There are few instruments used to sense north and estimating orientation such as; compass, electronics magnetometer, inertial gyroscope compass, digital magnetic compass, theodolite and Global Positioning System (GPS). The high quality gyroscopes, such as ring laser gyros able to maintain reading at high level, yet the device and technology is bulky and expensive. The accuracy of a compass and electronics magnetometer easily degraded by electromagnetic interference while GPS signals are not very reliable inside buildings. Hence, the MEMS gyroscope and accelerometer based north finding system is proposed to cater the raised problems. The automated system comprises of Micro-Electro-Mechanical System (MEMS) gyroscope and accelerometer mounted horizontal on the rotator laser, where the whole system controlled by microcontroller Arduino Mega. The system proven an accuracy with complementary filter factor, a = 0.97 while the rotator has been calibrated using autocollimator and observed that the rotator successfully rotating at ±0.02° for a rotation angle from 0 ° to 360 °. Moreover, the field test results prove that the developed system achieve an accuracy of ±1.5° with respect to the true north.

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Split-radix fast Fourier transform (SRFFT) is mainly for the implementation of a low-power FFT processor. FFT is an exceedingly proficient system to diminish calculation time and furthermore enhances the execution. In FFT calculations, SRFFT has less number of math Operations. With the approach of new innovation in the fields of VLSI and correspondence, there is likewise a constantly developing interest for rapid preparing and low range plan. Twiddle variables is required in FFT tending to processors. The flag stream chart of SRFFT is the same as radix-2 FFT thus regular tending to plans is utilized as a part of SRFFT. Notwithstanding, it has uncalled for game plan of Twiddle variables, and precludes the application from claiming radix 2 address era strategies. We demonstrate that SRFFT can be figured by utilizing a changed radix 2 butterfly unit. The proposed configuration accomplishes more than 20% lower control utilization while figuring a 1024-point complex-esteemed change. The proposed calculation comprises of blended radix butterflies, whose structure is more customary than the regular split radix calculation.

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In this study, a unique design in frequency reconfigurable antenna approach is proposed .The shown design in this paper can be used for Ku band downlink especially in satellites. A special employment includes a rectangular slot with four PIN diodes where the frequency reconfigurability is obtained. Four PIN diodes are used in the defected ground Structure where these diodes help in achieving reconfigurability easily. The antenna is designed and fabricated on FR4 substrate of dielectric constant 4.4 and thickness 1.6 mm. Simulation results of the proposed antenna are also shown in the study. Antenna design and simulation is done by using HFSS software.

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Tribological problems are extremely common in classical DI (Mechanical Direct Injection Diesels) and those update to CR (Common Rail) technology. These engines are still widely used in Power Generation, Diesel-electric locomotives and Marine applications. The original design of the first prototype, in a few cases, was conceived just after the First World War The marine environment and the continuous increase of performances and TBO provoked several tribological problems that have been partially solved through the years. However, significant improvements are still possible with modern technology in journal bearings, lubrication systems and lubricants. The journal bearing should float before applying load, for this reason start up originated problems cause 90% of the bearings failure. The relative speed between journal and bearing should be over a well-defined value to avoid boundary lubrication. For this reason, compression reduction devices can be used at star or the geometrical compression ratio should be reduced in favour of turbo-charging induced compression. Start velocity should be controlled and the lubrication system should be checked. Finally, a suitable lubricant should be used.

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In this paper described ways of recycling asphalt resin paraffin deposits (ARPD). Processing of oil waste and reducing their formation is a significant problem from the ecological point of view and requires new ecological and technological solutions. In this research paper analyzes the results of world practical experiments on the application of waste and presents technical solutions for the use of waste that are suitable for future application. The feature of this work is obtaining waterproofing materials based on asphalt - resin - paraffin deposits and polymer, moreover the improvement of its physicochemical properties.

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Particulate pollution by metals and metal oxides cause environmental and health hazards in different levels depending upon the spatial location and seasonal temporal variations. This paper aims to determine the level of bioaccumulation of particulate pollutants and its variation due to environmental location and seasonal impacts in a well-known versatile tropical waste land plant and bioindicator, Ricinus communis. The bioaccumulation across 3 sites namely residential, traffic prone and industrially polluted sites were chosen over two seasons namely dry and wet. The elemental compositional analysis was carried out using X-Ray fluorescence technology and micrographic images (SEM) were used to examine and compare the bio-accumulated particulate metallic pollutants in the aerial parts of the bio-indicator plant. The bioaccumulation of Pb was high in wet season than in dry season across all sites irrespective of the location, but the level of Pb accumulation was varying between sites due to influence of seasonal effects caused by monsoon indicating more accumulation in residential site due to industrial leach and percolation. Particulate accumulation of Ca and Fe and its oxides were persistently high both in dry and wet seasons in traffic prone site than the other 2 sites. Similarly, S, Si and their oxides were persistent across 2 seasons but, their levels were influenced by temporal factor of seasonal characters such as rain and arid climatic conditions, scoring high for wet season. The bio- accumulation of alkali earth metals, Na and Cl were influenced both by spatial and temporal factors such as anthropogenic activities and monsoon effects, accumulating more in industrial site and in wet season. This paper clearly demarcates the influence of spatial and temporal factors on 19 metallic and non metallic particulate matters and their oxides.

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Cyber-Physical Systems (CPSs) are currently widely used in people’s daily lives but present risks and threats, especially when used by cyber criminals against the governments, corporations, organizations, or individuals. CPS applications are increasingly becoming attractive and are targeted by cyber-attacks. Tools and theories that can be used by organizations and researchers to understand the types of new threats and the impacts that each threat can cause to the physical systems are lacking at present. In this research, current physical security threats of CPSs for the last few years are investigated to briefly describe the usage, application domains, and security challenges of CPSs in their field of application. This work serves a basis for further studies on cyber physical security.

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In today’s world of technical innovation, “compactness in everything” is the motto and this leverages reduction in the size of elements to be used in the design of any electronic product. Ultimately, the use of inductor is ruled out as it requires large number of turns of coil for any design at very low frequencies. However, there are certain circuits where inductor cannot be dispensed with. One such case is the audio frequency oscillator and a better choice is to go for designing oscillators using a simulated inductor. In this paper, oscillators implemented using a newly proposed tunable filter with simulated inductor is presented and the results are validated.

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The highlighted concept of this paper is to employing body bias concept in the design of 16 bit SRAM Array to operate the circuit for low voltage power supply and for achieving low power consumption and consequently reducing transistor count the GDI (Gate Diffusion Input) technique is adopted. By adopting GDI Technique design complexity levels also reduced. By utilizing Dynamic threshold logic and GDI Logic for SRAM cell design to effectively reduce static power dissipation and propagation delays compared to the resistive load inverter being used in previous designs. Peripheral components such as row decoder, precharge circuit, sense amplifier and column decoder has been designed and assembled to form SRAM array using Cadence (version 6.1.5) simulation tool. Standard UMC180 library is used for designing. Supply voltage of0.4V is considered. Transient responses for read and write operations for both logic-1 and logic-0 have been analyzed with operating Frequency 25MHz and the access time for read and write operation is 10ns. Power consumption of 101uW is measured for complete SRAM array.

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This paper presents the transfer of hexadecimal files from the computer to the PIC microcontroller wirelessly, using HC-06 Bluetooth module with a communication speed of 115200 baud. To meet this goal, it is necessary to install the Bootloader in the lower part of the Flash program memory of the PIC. So that, when it is necessary to update the programs in the microcontroller, reset it by the master clear to enter to Bootloader mode and transfer the hexadecimal file in serial form. For the tests, the microcontrollers PIC16F877A and PIC18F4550 were used.

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The main factors that cause the failure of gears are the bending stress and contact stress of the gear tooth. Stress analysis has been a key area of research to minimize failure and optimize design. This paper gives a finite element model for investigation of the stresses in the tooth during the meshing of gears. The model involves the involute profile of a spur gear for material Steel 15Ni2Cr1Mo28. The geometrical parameters, such as the face width and module, are considered important for the variation of stresses in the design of gears. Using modeling software, 3-D models for different modules in spur gears were generated, and the simulation was performed using ANSYS to estimate the bending and contact stresses. The Hertzian equation is used to calculate the contact stress. The results of the theoretical stress values are compared with the stress values from the finite element analysis.

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Ultra-wideband (UWB) communication systems have the promise of very high bandwidth, reduced fading from multipath and low power requirements. Band width can be extended to higher frequencies by adding a Octagonal or Hexagonal strip horizontally from the printed radiator and asymmetrically attaching a conducting strip to the radiator. This paper reports about the design of the antennas to enhance the bandwidth by increasing the size of the strip monopole by different geometries. The geometry of the wide Octagonal strip monopole is a Octagon of side 'a=9mm' where as for the wide Hexagon monopole is a Hexagon of side ‘a=10mm’.The strip length is 23mm and small gap 'd=3mm' between ground planes and strip for both the antenna geometries to achieve matching. The two printed monopole antennas are designed are etched onto a FR-4 epoxy substrate with an overall size of 45mm × 60mm ×1.6 mm. The proposed antennas are simulated using Ansoft HFSS and the practical results are obtained by testing the patches on Vector Network Analyzer. The Hexagonal strip monopole is resonating at 5.5 GHz and UWB impedance bandwidth (S11 < –10 dB) ranges from 1.54 to 9.41GHz, while the Octagonal strip monopole is resonating at 5.5GHz and UWB impedance bandwidth (S11 < –10 dB) ranges from 1.3 to 5.65 GHz. The VSWR values for Hexagonal is 1.52:1 at 2.09GHz & for Octagonal it is 1.53:1 at 1.78GHz.The Bandwidth for Hexagonal is 7.87GHz, while for Octagonal is 4.35GHz.

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The article deals with the problem of finding the place and time of switching on section heaters, with the stabilization of the temperature field based on the Green's function. The question of replacing conventional heating elements with impulse ones with the relay control principle is studied. The control system and the stabilization of the temperature field are considered. Mathematical models are presented and the temperature field is studied for a three-dimensional control object. Based on the results of this work, a patent for a utility model has been obtained.

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The paper describes the three new light-gas guns for the high-velocity throwing of mechanical particles: an upgraded two-stage light-gas gun and single- and three-stage compressed gas guns. The paper also provides the schemes, pictures and characteristics of light-gas guns.

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