Failure of welded materials in lap configuration due to poor adhesion bond or shear strength can lead to catastrophic damage to life and properties. Due to exponential demands for joined or welded components in lap configuration mode, It has become imperative to investigate and understand how a solid state joining process parameter can affect joint efficiency. Thus, this research study focuses on the effect of rotational speed and dwell time on the mechanical properties and the failure mode. Friction stir spot welding was used for the welding process. Three rotational speeds of 600, 900 and 1200 rpm and three dwell times of 5, 10 and 15 secs were used for the welding process. From the mechanical testing of the tensile shear strength, it was noticed that the magnitude of the tensile shear strength (TSS), tensile yield strength (TYS) and the fracture force (F. F.) depend on the choice of the rotational speed and dwell time. The maximum shear strength was found at the mid-rotational speed of 900 rpm. Ductile failure mode was noticed for all the samples during the fractography observations. Visual observation of the keyhole defects revealed that the diameter and depth of the keyhole were influenced by the process parameters, which also impacts the weld integrity and quality.

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In Assembly operations, drilling a machine component, made of nano metal matrix composite material, without any defect is a challenging task for Engineers. This work is focused on the effect of tool coatings and drilling parameters on the quality of holes made on Hybrid Aluminium nano composite. In this work, stir cast hybrid nanocomposite is developed with the reinforcement of 2% of boron nitride and 4% of Aluminium oxide nano particles in the base matrix of Aluminium 7075. This composite is used in various load bearing applications due to their excellent wear resisting properties. Circularity error and poor surface finish of the drilled holes are the major problems encountered in the drilling process. To improve the quality of drilling, it is essential to study these responses under various drilling conditions by varying the drilling parameters and drill tool coatings. The primary aim is to optimise the drilling parameters involved to minimise the circularity error and to maximise the surface finish of the drilled holes. Drilling experiments are conducted in CNC vertical machining centre using three different drill tools (Uncoated carbide drill, TiAlN coated drill and High carbon coated drill) of 5mm diameter. The different drilling parameters considered in our study are drilling speed and feed rate. L27 orthogonal array is used to conduct the experiments followed by Taguchi analysis and ANOVA to find out optimum process parameters and their percentage contribution on the responses considered.

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This research work proposes the analysis of predicted data of hydrate formation conditions in an intelligent optimization-based approach. The thermodynamic conditions for hydrate formation were used to assess the plugging risk. Hydrate formation thermodynamic properties and chemical reaction were statistical analyses on developed model results. Thus, the developed algorithm was applied to the experimental data of gas pipeline to validate the results. This research study improves the present models via a novel approach of an empirical model that predicts and suggests parameters for the thermodynamic hydrate formation conditions of methane gas.

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This paper presents the development of a manually-operated mechanical vegetable chopper. The fabricated device consists of a pusher assembly, blade assembly and base assembly. The device was designed to address the challenges of time consumption, hygienic problem and contamination, and injuries associated with the manual process of chopping vegetables using knife. Comparative study on the performance of the mechanical vegetable chopper and manual operation showed a considerable differences in cutting time and the quality of the output. Hence, the proposed device helps in saving time and effort in chopping vegetables, ensures safety to the users, and is environment-friendly due to absence of electricity and of noise to the operating environment.

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In this paper, High performance Low power 10-Bit, 250 MS/s Binary weighted Current steering DAC is presented. With the advent of high performance (in terms of speed, power and area) digital circuits, the need for data converters with high accuracy and speed for various kinds of applications, has attracted the attention of scientists and technologists all over the world. Constant efforts are being put in to miniaturize the data converters from the point of low power and less area. This proposed Digital to Analog Converter (DAC) is designed using 180nm CMOS Technology for High Speed Communication Systems. The architecture follows Binary weighted current steering technique. This technique is used because; it has a high conversion rate and good linearity. The proposed circuit uses binary-weighted current steering architecture rather than segmentation because this structure achieves a high Spurious-Free Dynamic Range (SFDR) at the high clock frequency. Current steering does not require a buffer because it uses a load resistor directly for the current. The Digital to Analog Converter is designed and implemented in0.185m CMOS process with supply voltage of 1.8v. The power consumption achieved is 19.795m & Best SFDR(dB)@Fin(MHz) is 68@11.23.

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The reinforcement of solid wood and wood-based composite materials is not a new idea, but there have been very few studies about reinforcing plywood with glass fiber composite. In this study, woven glass fibers were used on both outer surfaces of plywood sandwich laminates composite with the help of epoxy resin to improve mechanical properties of standard plywood laminated. The vacuum bagging technique was applied to fabricate plywood sandwich laminate composite test samples with three different thicknesses which is 3 mm, 5 mm and 9 mm, and their mechanical properties were analyzed using tensile and surface roughness tests for different cutting speed parameters of laser cut machine. The collected data were analyzed using analysis of variance (ANOVA), and the microscopic investigation was performed to examine the cross-section structure of ruptured surfaces and its failure morphology during cutting process.

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Nowadays, lots of disciplines require optimization to determine optimal parameters to accomplish top quality services which include parameters optimization of thin film coating. Modification of sharp tool characteristics and costs are two primary matters in the procedure of Physical Vapour Deposition (PVD). The purpose of this study is to figure out the optimal parameters in PVD coating process for better thin-film roughness. Three input parameters are chosen to describe the solutions over the target data, such as Nitrogen gas pressure (N2), Turntable speed (TT), and Argon gas pressure (Ar), although the surface roughness had been chosen being a result response of the Titanium nitrite (TiN). Atomic Force Microscopy (AFM) tools were applied to describe the roughness of coating layer. Within this research, a process of modelling using Response Surface Method (RSM) was applied for surface roughness of Titanium Nitrite (TiN) coating to get a best result. Particle Swarm Optimization (PSO) was applied as an optimization technique for the coating process to enhance characteristics of thin film roughness. In validation process, different experimental runs of actual data were conducted. In validation process, it was found that residual error (e) is less than 10, to indicate that the model can accurately predict the surface roughness. Also, PSO could reduce the value of coating roughness at reduction of  48% to get a minimum value compared to actual data.

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The use of botanical substances to encountercitrus psyllid in the framework of integrated HLB control in citrus has been studied. Intercropping tangerine and guava were expected to reduce psyllid visit on tangerine plants and also incidence of HLB. The objective of this research was to evaluate the intercropping of tangerine and guava in relation to the presence of D. citriKuw. and HLB infection. The research was conducted from January 2016 to June 2019 and was designed to facilitate 3 planting types between tangerine and guava, i.e. intercropping of tangerine with guava Sukun, intercropping of tangerine with guava Jakarta and monoculture of tangerine. The results showed that the population of psyllid seasonally fluctuated accordingly with the availability of the tangerine juvenile shoots. Along the observation periods; the psyllid population was lower under intercropping tangerine with guava than monoculture tangerine. The visual symptom of HLB was detected after 22 months planting and most of the visually suspected shoots were confirmed by PCR. After 25 months planting, the disease intensity decreased from 18.95 to 4.16% in intercropping tangerine with guava Jakarta and 18.95 to 2.08% in intercropping of tangerine with guava Sukun. In terms of area infection, the suppression of HLB was 65% in intercropping tangerine with guava Jakarta and 77% in intercropping tangerine with guava Sukun, when compared to monoculture tangerine. This study demonstrated that HLB intensity and area infection were lower in the intercropping of tangerine and guava than monoculture of tangerine.

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Pressure is one of the common parameters in Process Control whereby the periodic calibration needs to be done. Calibration is an important element in the measurement process instrumentation readings. Works on calibration will be run periodically according to a pre-set schedule depends on how critical readings in need of the processes involved. If it is critical, works calibration will be run more frequently and vice versa, if readings are in need is for monitoring purposes only. Works calibration for pressure transmitter will be executed in two ways, namely in house and field calibration. Currently for both methods, the calibration will be run manually by a service engineer. The method used for supplying air pressure to the pressure transmitter is by using manual hand pump. The reading and data from the transmitter are presented the digital manometer. The calibration report is then generated manually by the engineer. The instrument for the calibration is particularly a pressure transmitter. For the calibration, at least two transmitters will be used. One pressure transmitter must be a Master Standard Unit (MSU), and the other(s) will be Unit under Test (UUT). For this paper, the manual method is replaced by automatic control by utilising electrical and electronic equipment that is controlled by PID controller.

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In recent digitalized world, Wireless Sensor Networks (WSNs) are highly deployed for data transfer between sensor nodes through wireless channels. Normally, these sensor nodes have limited power resources and so the use of these resources has become the most challenging process during Data Aggregation (DA). To avoid this condition, a Power-aware Clustering and Routing with Compressive sensing Protocol (PCRCP) has been recommended for balancing the power use during transferring and aggregating the data between Cluster Head (CH) and Base Station (BS). In this protocol, Compressed Sensing (CS) method is proposed for aggregating the data from CHs with the aid of Forwarder Node (FN). However, still DA process has high data transmission cost and number of measurements. Therefore in this article, a Power-aware Clustering and Routing with Improved Compressive sensing Protocol (PCRICP) is suggested to ensure the energy efficiency of DA in WSNs. Primarily, a coalition formation-based CS solution is proposed that utilizes the signals sparsity distribution for assembling nodes into many coalitions and the CS is executed inside each coalition. Also, a 2-stage Belief Propagation (BP)-based restoration strategy is applied to achieve an acceptable data quality during DA process. This BP algorithm is an iterative data transfer method which determines the marginal distribution or discovers the Most Probable Assignment (MPA) in the Bayesian networks. On the other hand, it has a convergence problem and the design accuracy is differed with the graph cyclicity. So, an improved generalized BP-based algorithm is proposed that can guarantee better convergence in Markov Random Fields (MRFs). In this algorithm, a caching method and chessboard transitory policy are employed to speed-up the convergence. Also, the computational difficulty of group information from quadric to cubic is reduced. Finally, the simulation results exhibit that the PCRICP achieves superior effectiveness than the PCRCP in terms of different network metrics.

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The Colombian Platinum alluvium are made up of platinum, iridium, osmium and palladium. Iridium and Osmium confer a refractoriness condition that makes alluvium leaching difficult, being the first aspect to be solved in the development of a refining process. Microwave acid leaching offers a higher leaching rate with high levels of recovery, so it seems a possible process to move forward in this regard. For this reason, this article aims is to selected materials for the fabrication of a low-cost industrial reactor with a volume capacity of 180 ml fulfilling the requirements of pressure, temperature, chemical resistance, easy fabrication and safety. Materials selection was made using an Ashby methodology. Reactor was divided in six different subsystems. The first step of the Ashby methodology resulted in a mechanical, chemical and thermal properties list, including objectives to minimized some properties and material index in order to choose the best material. The screen-out step was made using ANSYSGRANTA SELECTOR software and obtained four materials. The availability of this materials in Colombia was constated, choosing finally PTFE and POM-H. A reactor fabrication was made by CNC and a test to measure the reached temperature on the reactor wall was made, resulted in values 200C below of services temperature of the material.

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The following document aims to present a territorial accessibility analysis of the set of Primary Activity Nodes in the municipality of San Andris de Tumaco, Colombia, making use of the municipality's transportation infrastructure network. The research methodology contemplates the application of geo-statistical models of accessibility, executed by making use of digital GIS-type tools and complemented by an analysis of population and area coverage. As main results it is obtained that the maximum coverage times in the municipality do not exceed 22 minutes; likewise, the joint analysis shows some sectors with shortcomings regarding local coverage. With this, it is possible to conclude that the accessibility of the municipality, regarding its activity nodes, is adequate, considering the comparison with access times in other cities.

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The agriculture sector in a developing country like India still requires proper irrigation facilities and the motivation of the farmers towards cultivation. The government of India has already planned to implement the scheme of 10 lakh grid-connected solar water pumps by 2022; thereby the farmers can generate the revenue through the excess energy supplied to the grid. The novelty of this work has two objectives. First, the reduction of the total amount of energy consumption on all the feeders when a grid-connected Solar Water Pumping System (SWPS) used in place of the conventional grid system. The annual energy consumption of 15.65M.U is reduced to 7.64M.U when the SWPS is used in place of conventional grid supply. A total of 19 feeders merely for agriculture purposes are considered in this study at Rajanagaram, Andhra Pradesh, India. Second, the operation of the pumps in different combinations to estimate the performance indices like net Life Cycle Cost (LCC), Levelized Energy Cost (LEC), and pump operating time. In this particular study, 1.2HP, 3HP, and 5HP pumps are considered individually and also with seven different combinations. Out of the total ten combinations, three are selected based on the performance indices. The entire analysis is carried out in this paper concerning the paddy field as it is one of the major crops in the area of the study and as well as across the country. This study helps to understand the need for the implementation of the grid-connected SWPS for the sustainable energy and economical growth of the country.

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Wide band antenna design had consequently drawn more attention from academic to industries. So wide band antennas should be capable of operating over an ultra wide band and also cover high frequency bands. At the same time, small and compact antenna size is required to integrate it on to communication systems. This work focuses on the design of an ultra compact rectangular monopole with corner feed. The size of the antenna is 22W20mm2, fabricated on an FR4 substrate with 1.6mm thickness. An asymmetrical rectangular ground is introduced with a rectangular cut below the feed. The monopole works over a broad band beyond 7.5GHz. A reversed U shaped opening on the rectangular patch presents a stop band (6.5-7.1GHz). With inverted L shaped slot (L1) on the ground presents second notched band (11-11.69GHz). Another Inverted L shaped slot (L2) is introduced on to the ground outcomes another notched band (13.16-13.93 GHz). The proposed antenna is simulated for VSWR, radiation pattern, total gain and current density.

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The increasing amount of agricultural wastes generated is one of the major environmental problems in the country. Without proper segregation and utilization of these materials can cause pollution and may lead to environmental destruction. In this study, a particle board is developed utilizing various composition of sawdust, rice husk and starch. Different formulations of sawdust (30-60%) and rice husk (25-55%) and 15% starch with a fixed quantity of glue were tested for water absorption and density. Meanwhile, the performance of the pressing machine in developing the particle board was also evaluated. The testing of the machine was done to determine the various temperature of both molder and particleboard. Results showed that the maximum temperature of the side cover was 90°C while the surface and core layer temperatures of particleboard were 120°C and 87.62°C, respectively. The water absorption increases as the amount of rice husk decreases. Based on the density, the particle boards were classified as low-density grade type.

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