Sustainable Analysis of Process Parameters during MIG Welding of 1018 Mild Steel

The present work analyses MIG in terms of strength and consumption of energy during joining of similar AISI 1018 Mild Steel plates. Sustainable manufacturing is the creation of various manufactured products that generally use different processes that will minimize negative impact on environment, conserve natural resources and energy, are also safe for the employees, consumers and communities as well as economically sound. Sustainable manufacturing highlights on the necessity of an energy effective process that optimize consumption of energy. AISI 1018 mild steel is extensively used in automotive industries for pins, worms, dowels gears, non-critical tool components etc. Main important output responses are Tensile Strength and energy consumption during MIG Welding Process by taking Current, Travel Speed and Voltage as effective input variables. The main objective is to optimize energy consumption as well as tensile strength also determination of main influential process parameters on energy Consumption and tensile strength by using Taguchi Method. Contour plot has been also shown.

Sustainable Analysis of Process Parameters during TIG welding of dissimilar joining between 304 Stainless Steel and AISI 1018 Mild Steel

The present work investigates TIG in terms of strength and energy consumption during joining of dissimilar metal plates between 304 Stainless Steel and AISI 1018 Mild Steel. TIG welding basically promotes a sustainable environment because it consumes less energy. Energy conservation means to reduce imbalance between demand and energy supply that is necessary to protect ecological resources and natural environment. TIG welding is a precision welding process which makes possible for joining of thinner and lighter materials. Joining of various dissimilar metals becomes great interest owing to the different challenges that are posed by deviation in the material composition as well as the characteristics of the joined metals. The main objective is to optimize energy consumption and tensile strength by taking effective process parameters that are Current, Travel Speed and Gas Flow Rate and also determination of main influential process parameters on energy consumption and tensile strength by using Taguchi method. Contour plot has also been shown in this present investigation.

Interaction among a lump, periodic waves, and kink solutions to the KP-BBM equation

The Hirota bilinear method is prepared for searching the diverse soliton solutions to the (2+1)-dimensional Kadomtsev–Petviashvili–Benjamin–Bona–Mahony (KP-BBM) equation. Also, the Hirota bilinear method is used to find the lump and interaction with two stripe soliton solutions. Interaction among lumps, periodic waves, and one-kink soliton solutions are investigated. Also, the solitary wave, periodic wave, and cross-kink wave solutions are examined for the KP-BBM equation. The graphs for various parameters are plotted to contain a 3D plot, contour plot, density plot, and 2D plot. We construct the exact lump and interaction among other types of solutions, by solving the underdetermined nonlinear system of algebraic equations with the associated parameters. Finally, analysis and graphical simulation are presented to show the dynamical characteristics of our solutions, and the interaction behaviors are revealed. The existing conditions are employed to discuss the available got solutions.

Losses in Efficiency Maps of Electric Vehicles: An Overview

In some applications such as electric vehicles, electric motors should operate in a wide torque and speed ranges. An efficiency map is the contour plot of the maximum efficiency of an electric machine in torque-speed plane. It is used to provide an overview on the performance of an electric machine when operates in different operating points. The electric machine losses in different torque and speed operating points play a prominent role in the efficiency of the machines. In this paper, an overview about the change of various loss components in torque-speed envelope of the electric machines is rendered to show the role and significance of each loss component in a wide range of torque and speeds. The research gaps and future research subjects based on the conducted review are reported. The role and possibility of the utilization of the computational intelligence-based modeling of the losses in improvement of the loss estimation is discussed.

Formulation and Evaluation of Ibuprofen Fast Dissolving Tablets Employing Starch Malonate (Modified Starch) as a Superdisintegrant

Aim: The goal of the study was to prepare a superdisintegrant named starch malonate followed by its evaluation for physicochemical properties. Prepared starch malonate was optimized in the preparation of fast dissolving tablets of ibuprofen by using 23 factorial designs. Methods: Compatibility studies like FTIR, TLC and DSC were performed to check any interaction between starch malonate and ibuprofen. Fast dissolving tablets were compressed by direct compression method and subjected to various official tests like hardness, friability, drug content, dissolution etc. Wetting time and water absorption ratio were also performed. At last response surface plot and contour plot was plotted to check the effects of starch malonate, croscarmellose sodium and crospovidone (independent variables) on disintegration time and dissolution efficiency in 5 minutes (dependent variables). Stability studies were also performed to check the stability of prepared fast dissolving tablets of ibuprofen. Results: Results of the studies showed that all the results are within acceptable limits and complying with the criteria of fast dissolving tablets. Drug content was found to be (100±5%), hardness of all tablets were found in between 3.8 -4 kg/cm2, friability was found less than 0.15%. Optimized formulation has showed less wetting time, less disintegration time followed by enhanced drug release. Among all formulation, formulation F2 has shown least disintegration time and enhanced drug release (99.89%) as compared to other formulations. We can conclude that starch malonate can be used as a novel superdisintegrant.

A higher-order numerical analysis to study the flow physics and to optimize the design of a short-dwell blade coaters for higher efficiency

Blade coaters are most commonly used for coating of paper and paperboard with higher efficiency. The efficiency of short-dwell blades coaters depends on many factors such as the properties of the coating material, design of the coating reservoir, the types of flow behaviour taking place inside the reservoir, etc. In this work, we have proposed an optimal design of the reservoir to improve the efficiency of short-dwell coaters. The reservoir has been modeled as flow inside a two-dimensional rectangular cavity. Incompressible Navier-Stokes equations in primitive variable formulation have been solved to obtain the flow fields inside the cavity. Spatial derivatives present in the momentum, and continuity equations are evaluated using a sixth-order accurate compact scheme whereas the temporal derivatives are calculated using the fourth-order Runge-Kutta method. The actual rate of convergence of the numerical scheme has been discussed in detail. In addition, the accuracy and stability of the used numerical method are also analysed in the spectral plane with the help of amplification factor and group velocity contour plot. The obtained numerical solutions have been validated with the existing literature. Four different aspect ratio cases (L/H = 3/4,4/3,4/5 and 5/4) have been considered for the simulations including the case of square cavity. It has been observed that L/H = 5/4 case provides best results among all others.

Combining thermal insulation and mobile communication in buildings: influence of laser-treated glazing on microwave propagation

With the purpose of reducing the heating energy in buildings, it is common practice to install energy-efficient windows to increase the thermal insulation of a façade. These insulating glass units (IGIJ) include a thin silver coating acting as an infrared mirror which reduces the thermal losses that occur through radiation, but at the same time reflects the microwaves for mobile communication. To address this drawback, a specific laser treatment is performed on the silver coating which strongly improves the transmission of microwaves through the window. In this study, the attenuation of microwaves signal was analyzed inside the SolAce unit in the "NEST" research building at the Swiss Federal Laboratories for Materials Science and Technology (EMPA) in Dübendorf. Two configurations (with and without laser-treated glazing) were carried out by interchanging two hinged windows. The results showed a significant improvement in signal strength in the configuration with laser-treated IGUs. A transmission loss contour plot of the SolAce unit showed a highly directional propagation of the wave which suggests that more than two windows should be treated to achieve better mobile communication in the entire unit. The novel patterned coating is thus especially valuable in the building sector to increase the microwave signal for mobile communication. To the best of our knowledge, this is the first implementation and testing of laser-treated coating for energy-efficient glazing in the building sector.

Exploring Dielectric Constant and Dissipation Factor of LTCC Using Machine Learning

Low-temperature co-fired ceramics (LTCCs) have been attracting attention due to rapid advances in wireless telecommunications. Low-dielectric-constant (Dk) and low-dissipation-factor (Df) LTCCs enable a low propagation delay and high signal quality. However, the wide ranges of glass, ceramic filler compositions, and processing features in fabricating LTCC make property modulating difficult via experimental trial-and-error approaches. In this study, we explored Dk and Df values of LTCCs using a machine learning method with a Gaussian kernel ridge regression model. A principal component analysis and k-means methods were initially performed to visually analyze data clustering and to reduce the dimension complexity. Model assessments, by using a five-fold cross-validation, residual analysis, and randomized test, suggest that the proposed Dk and Df models had some predictive ability, that the model selection was appropriate, and that the fittings were not just numerical due to a rather small data set. A cross-plot analysis and property contour plot were performed for the purpose of exploring potential LTCCs for real applications with Dk and Df values less than 10 and 2 × 10−3, respectively, at an operating frequency of 1 GHz. The proposed machine learning models can potentially be utilized to accelerate the design of technology-related LTCC systems.

Performance enhancement of a diesel engine with a rotating injector – a numerical study

Improving engine performance is a constant challenge and various methodologies have been adopted by researcher’s world over. In this work, the dispersion characteristics of a rotating injector is studied by varying the umbrella angle (UA) followed by its combustion characteristics and comparing it to a static 3 – hole injector. The present numerical study is bench marked with the experimental data obtained from open literature for a 2 – hole injector with various umbrella angles. The volume fraction of the dispersed fuel along with its spray structure in relation to spray width is compared. This is done by processing the numerical contour plot using LabView image processing utility with appropriate calibration. From this study the 130 degree UA injector configuration was found to be effective when compared with 70. The combustion characteristics is now studied for this injector. It is found that the rotating injector has better dispersion and lowers NOx by 14 % when compared to a static injector with a very marginal loss in thermal efficiency. The rotary system has a lower heat release but a wider spread in comparison to a static case. This helps in marginally reducing the in-cylinder temperature and pressure lower NOx.

Environmental asbestos exposure and clustering of malignant mesothelioma in community: a spatial analysis in a population-based case–control study

Background Neighborhood exposure to asbestos increases the risk of developing malignant mesothelioma (MM) in residents who live near asbestos mines and asbestos product plants. The area of Casale Monferrato (Northwest Italy) was impacted by several sources of asbestos environmental pollution, due to the presence of the largest Italian asbestos cement (AC) plant. In the present study, we examined the spatial variation of MM risk in an area with high levels of asbestos pollution and secondly, and we explored the pattern of clustering. Methods A population-based case–control study conducted between 2001 and 2006 included 200 cases and 348 controls. Demographic and occupational data along with residential information were recorded. Bivariate Kernel density estimation was used to map spatial variation in disease risk while an adjusted logistic model was applied to estimate the impact of residential distance from the AC plant. Kulldorf test and Cuzick Edward test were then performed. Results One hundred ninety-six cases and 322 controls were included in the analyses. The contour plot of the cases to controls ratio showed a well-defined peak of MM incidence near the AC factory, and the risk decreased monotonically in all directions when large bandwidths were used. However, considering narrower smoothing parameters, several peaks of increased risk were reported. A constant trend of decreasing OR with increasing distance was observed, with estimates of 10.9 (95% CI 5.32–22.38) and 10.48 (95%CI 4.54–24.2) for 0–5 km and 5–10 km, respectively (reference > 15 km). Finally, a significant (p < 0.0001) excess of cases near the pollution source was identified and cases are spatially clustered relative to the controls until 13 nearest neighbors. Conclusions In this study, we found an increasing pattern of mesothelioma risk in the area around a big AC factory and we detected secondary clusters of cases due to local exposure points, possibly associated to the use of asbestos materials.