Variations In Input Parameters Research Articles

Preliminary assessment of ground-source heat exchangers for cooling in Hawai‘i

This study provides a preliminary assessment of ground source heat exchangers (GSHE) for cooling applications in the tropical environment of Hawai‘i. Recent demonstrations proved GSHE capacity for space cooling in tropical southeast Asia. We present multiple engineering scenarios in which GSHE could be feasible across Hawai‘i, highlighting regions of interest. Limestone and basalt provide the best host geology, feasible when air-ground temperature differences are >4 C and cooling is only required for Hawai‘i’s five summer months. This work investigates the effect of varying input parameters such as energy efficiency ratio, rock thermal conductivity, piping thermal resistance, temperature gradient, and fraction of time operating on the length of cooling loop required to successfully operate a GSHE. Maps of depth to water are provided, as well as calculations of Peclet numbers for basalt, limestone, and alluvium. Basalt’s Peclet number shows advection is a more dominant process than conduction in heat exchange; limestone has equivalent advective and conductive processes; alluvium is dominated by conduction. Thus, both basalt and limestone may have an increased capacity to efficiently act as heat sinks in Hawaiian environments as groundwater flow could additionally transfer heat through advection, not relying solely on the calculated capacity of conductive heat exchange.

Performance comparison of a MSW settlement prediction model in Tehran landfill

The municipal solid waste (MSW) landfills experience a large post-closure settlement over time. Waste settlement significantly impairs utilities, structures, and the other facilities constructed on top of a landfill. This study presents the settlement mechanisms and the methods of estimating MSW landfill settlements. Since the waste materials exhibit engineering properties which vary depending on many factors such as the location, time, climate, this study also presents the data related to the landfill characteristics, waste composition, waste moisture content, and other physical and chemical properties of waste. In addition, this paper discusses the findings of a settlement investigation conducted at a municipal solid waste landfill in Tehran. In this research, based on the collected field data and data obtained from the available literature, a technical management tool for MSW closed landfills has been developed using MATLAB, which aims to predict time dependent settlement under self-weight and surcharge loads in landfills considering various related parameters, leachate, gas generation, and moisture distribution, coefficients of compression, whilst it calculates different properties of wastes, and determines the landfill slope stability under various conditions. This user-friendly program captures the variation of the model parameters with time. The results of the verification process indicate that the results from the technical management tool have been in a very good agreement with the measured field settlement data, collected from Tehran landfill.Moreover, the results of sensitivity analysis of the model in regard to variation of input parameters indicate that there are two prominent characteristics, having significant impacts on the overall landfill settlement. These characteristics are the landfill height and the compressibility parameters.The outcomes of this study can improve the confidence for design and construction on MSW landfills. It may reduce the uncertainty when predicting the landfill settlement and enable to apply the landfill redevelopment techniques more effectively and efficiently. Studying the creep settlement properties under the co-effect of stress, biodegradation and temperature for predicting the total landfill settlement is recommended for future studies.

Precipitation data and their uncertainty as input for rainfall-induced shallow landslide models

Physical models used to forecast the temporal occurrence of rainfall-induced shallow landslides are based on deterministic laws. Owing to the existing measuring technology and our knowledge of the physical laws controlling landslide initiation, model uncertainties are due to an inability to accurately quantify the model input parameters and rainfall forcing data. An uncertainty analysis of slope instability prediction provides a rationale for refining the geotechnical models. The Transient Rainfall Infiltration and Grid-based Regional Slope Stability-Probabilistic (TRIGRS-P) model adopts a probabilistic approach to compute the changes in the Factor of Safety (FS) due to rainfall infiltration. Slope Infiltration Distributed Equilibrium (SLIDE) is a simplified physical model for landslide prediction. The new code (SLIDE-P) is also modified by adopting the same probabilistic approach to allow values of the SLIDE model input parameters to be sampled randomly. This study examines the relative importance of rainfall variability and the uncertainty in the other variables that determine slope stability. The precipitation data from weather stations, China Meteorological Administration Land Assimilation System 2.0 (CLDAS2.0), China Meteorological Forcing Data set precipitation (CMFD), and China geological hazard bulletin are used to drive TRIGRS, SLIDE, TRIGRS-P and SLIDE-P models. The TRIGRS-P and SLIDE-P models are used to generate the input samples and to calculate the values of FS. The outputs of several model runs with varied input parameters and rainfall forcings are analyzed statistically. A comparison suggests that there are significant differences in the simulations of the TRIGRS-P and SLIDE-P models. Although different precipitation data sets are used, the simulation results of TRIGRS-P are more concentrated. This study can inform the potential use of numerical models to forecast the spatial and temporal occurrence of regional rainfall-induced shallow landslides.

The Impact of Powering an Engine with Fuels from Renewable Energy Sources including its Software Modification on a Drive Unit Performance Parameters

The application of fuels from renewable energy sources for combustion engine powering involves a great demand for this kind of energy while its production infrastructure remains underdeveloped. The use of this kind of fuel is supposed to reduce the emission of greenhouse gases and the depletion of natural resources and to increase the share of renewable energy sources in total energy consumption and thus support sustainable development in Europe. This study presents the results of research on selected performance parameters of transport by internal combustion engines including: power, torque, the emission of sound generated by the engine, the content of exhaust components (oxygen O2, carbon monoxide CO, carbon dioxide CO2, nitrogen dioxide NO2), and the content of particulate matter (PM) in exhaust emission. Three self-ignition engines were tested. The fuel injection controllers of the tested internal combustion engines were additionally adjusted by increasing the fuel dose and the load of air. The material used in the tests were mixtures of diesel oil and fatty acid methyl esters of different concentration. A statistical analysis was performed based of the results. The purpose of the work was to develop a resulting model for assessing the operation of engines fueled with biofuel and diesel mixtures while changing the vehicle’s computer software. A computer simulation algorithm was also developed for the needs of the tests which was used to prognose the state of the test results for variable input parameters.

Identification of mammary lesions in thermographic images: feature selection study using genetic algorithms and particle swarm optimization

The incidence of breast cancer increases every year. Early detection of the disease is critical since the sooner the disease is discovered the better are the treatments and the chances of cure. Mammography is now the gold standard for the diagnosis of breast cancer, but this screening tool has some limitations. Infrared thermography is being studied as a complementary tool due to its benefits. The combination of specialized professionals with methods of digital image analysis in breast thermography can contribute to improve diagnosis performance. From this, several research groups have been proposing methods to treat these data. Feature selection plays a fundamental role in this process, since it may optimize the machine learning process. In this study, we propose a feature selection approach using genetic algorithms (GA) and particle swarm optimization (PSO) in thermographic images with breast lesions. The main goal of this approach is to optimize the identification and classification of breast lesions. We used several classifiers to assess the performance of the subsets with selected features. Support vector machines were more effective in these experiments. It was possible to reduce from 169 features with accuracy of 91.12% to 57 features with accuracy of 87.08% using the genetic algorithm. We also found a subset of 60 features with an accuracy of 86.16% using PSO. The features selection step could optimize classification time and computational cost. By varying input parameters, we could achieve a significant reduction in the amount of features. Features reduction could be done without losing much in accuracy, when compared to the whole set of features.

Investigation of the key process parameters in the hot forming of a shackle

To investigate the impact of the variations of different input parameters in the multi-stage hot forging process of a shackle, an analysis is carried out through numerical simulations of the whole manufacturing process. Due to the complexity of the process and the large number of factors influencing the thermo-mechanical forming process, the investigation is focused on the workpiece positioning, the temperature of the tools, the transportation time and the contact-friction conditions. The analysis is narrowed down to the key stages of the process that are closed-die forging and ram bending. Coupled with experimental measurements, a comparison of forging loads, functional dimensions and shackle geometry is presented. It is shown that the conformation of shackle geometry to the industrial specifications depends mainly on the workpiece positioning and the transportation time. The dispersion measured in the forging load and in the main dimensions can thus be explained and these observations can be used to improve the manufacturing process for shackles.

Simulation of float of 19 passenger aircraft during landing on water surface

The 19-passenger plane was modified to land in the water by making a landing gear with a float. The floats used are imported products that have previously been used by similar aircraft. Float must be able to support the aircraft and can accept impact loads when landing. This study aims to determine the effect that occurs in float when making water surface landings. Stress and displacement are simulation outputs that are the focus of research. These parameters are obtained by numerical simulation methods based on Civil Aviation Safety Regulation (CASR) by varying input parameters such as: landing speed. From the results of the study it was found that the faster the velocity then the output of the stress and displacement response from the float becomes larger.

Effects of processing parameters on the micro-drilling through fast hole electroerosion and laser trepanning in Inconel 718

Electroerosion and laser drillings are techniques used in manufacturing microholes in materials that are difficult to machine. Small diameter holes (between 0.18 and 2 mm) are commonly used in the aeronautical industry and gas turbine components as elements of the cooling system of hot side blades. This study aims to evaluate the effect of different machining parameters on the dimensional and microstructural quality of microholes obtained by the two manufacturing techniques cited. These effects were yield and dimensional analysis, the presence of micro-cracks, and width of the zone affected in the micro-drilling of Inconel 718. For this, microholes were produced through fast hole drilling electroerosion, using two electrode materials, copper and brass, and through Nd:YAG laser micro-drilling by trepanation. A central composite statistical design was defined to evaluate the influence of input parameter variations. Results were compared and showed that although the laser trepan process productivity is higher than that of electroerosion, laser drilling generates a greater concentration of cracks in the HAZ (heat-affected zone) when compared to the microholes manufactured by electroerosion. Therefore, assessment of the process to be used depends on the features one wants to optimize. Each manufacturing process has advantages and limitations that must be taken into consideration for selecting one of the techniques, and the project of the component should present the essential requirements for choosing the proper manufacturing process.

Uncertainty analysis of the Limits to Growth model: sensitivity is high, but trends are stable

Since publication, the Limits to Growth model has received both praise and criticism. One criticism is the model’s sensitivity to input error. We have performed an uncertainty analysis to see in retrospect if the model’s sensitivity was of concern. The results show that standard deviations of output variables are high. The general trends of the variables, however, are predictable, with very similarly shaped trend lines. Trajectories indicating a favourable future for humankind (i. e., without a severe decline in population and resources) stay in areas of low probability.Uncertainty analysis is an important step in determining the reliability of a model. Models which are used to determine policies or guide decisions must be reliable to ensure sound choices are made. The Limits to Growth model by Donella Meadows and colleagues was one of the first computer models to investigate global issues of population growth and resource constraints. The model received much attention and criticism, sometimes being accused of being too sensitive to variations in input parameters. This paper studies the model’s sensitivity to input error through an uncertainty analysis, and examines if this sort of analysis could have affected the debate surrounding the model’s reliability and usefulness. Results showed that given the data used to calibrate the model, the output was susceptible to large variations, with the population variable returning a normalised standard deviation of 0.43. However, despite input error, the trends of the variables remain predictable.

MHD conjugate natural convection in a porous cavity involving a curved conductive partition and estimations by using Long Short-Term Memory Networks

In this study, MHD conjugate free convection of a porous cavity having a curved shape conductive partition is numerically analyzed by using the Galerkin weighted residual finite element method. The numerical simulation is performed for different values of pertinent parameters: Rayleigh number (between $$10^4$$ and $$10^6$$), Hartmann number (between 0 and 60), Darcy number (between $$5 \times 10^{-4}$$ and 0.05), porosity of the medium (between 0.25 and 0.75), curvature of the partition (minor axis radius of the horizontal ellipse, between 0.01H and 0.3H) and conductivity ratio (between 0.05 and 50). It was observed that the heat transfer rate enhances locally and in average for higher values of Rayleigh number, Darcy number, porosity of the medium and conductivity ratio, whereas the impact is opposite for higher values of Hartmann number. The amount of average Nusselt number reduction is obtained as $$22\%$$ when Hartmann number is changed from 0 to 60 at Rayleigh number of $$10^5$$. Curvature and conductivity of the curved partition affect the variation in fluid flow and heat transfer characteristics. Maximum of $$7\%$$ variation in the average Nusselt number is achieved when the curvature of the conductive partition is varied but the effects of thermal conductivity ratio on heat transfer rate are higher. Long Short-Term Memory Networks are used for estimation of the velocity and temperatures in the computational domain for various values of pertinent input parameters variation in the system which includes conjugate heat transfer mechanism in a porous enclosure with complex-shaped conductive partition under the effects of magnetic field.

Cost-Effectiveness of Multigene Pharmacogenetic Testing in Patients With Acute Coronary Syndrome After Percutaneous Coronary Intervention

ObjectiveTo evaluate the cost-effectiveness of multigene testing (CYP2C19, SLCO1B1, CYP2C9, VKORC1) compared with single-gene testing (CYP2C19) and standard of care (no genotyping) in acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI) from Medicare’s perspective. MethodsA hybrid decision tree/Markov model was developed to simulate patients post-PCI for ACS requiring antiplatelet therapy (CYP2C19 to guide antiplatelet selection), statin therapy (SLCO1B1 to guide statin selection), and anticoagulant therapy in those that develop atrial fibrillation (CYP2C9/VKORC1 to guide warfarin dose) over 12 months, 24 months, and lifetime. The primary outcome was cost (2016 US dollar) per quality-adjusted life years (QALYs) gained. Costs and QALYs were discounted at 3% per year. Probabilistic sensitivity analysis (PSA) varied input parameters (event probabilities, prescription costs, event costs, health-state utilities) to estimate changes in the cost per QALY gained. ResultsBase-case–discounted results indicated that the cost per QALY gained was $59 876, $33 512, and $3780 at 12 months, 24 months, and lifetime, respectively, for multigene testing compared with standard of care. Single-gene testing was dominated by multigene testing at all time horizons. PSA-discounted results indicated that, at the $50 000/QALY gained willingness-to-pay threshold, multigene testing had the highest probability of cost-effectiveness in the majority of simulations at 24 months (61%) and over the lifetime (81%). ConclusionsOn the basis of projected simulations, multigene testing for Medicare patients post-PCI for ACS has a higher probability of being cost-effective over 24 months and the lifetime compared with single-gene testing and standard of care and could help optimize medication prescribing to improve patient outcomes.

Numerical comparison of usual Arrhenius-type equations for modeling ionic transport in solids

The primary objective of this work is to draw attention to the inherent differences between Arrhenius-type equations used for modeling ionic conductivity in solids. The used methodology comprises a comparison between the two most used Arrhenius-type equations by generating data applying one equation and fitting them by using the other equation. Data are generated in different conditions by varying input parameters such as the extent of the temperature range and the average temperature of this range, as well as the pre-exponential term and activation energy of the Arrhenius-type equation. The fitting procedure is performed by plotting the generated data based on the linearized form of those equations followed by the linear fitting. The results show a substantial difference between the activation energy value of those equations, which is mainly dependent on the average temperature of the range. In contrast with the widely held perception that differences in the activation energy of both equations usually can be neglected, this work reveals that relative differences between activation energy of these equations are usually significant. These relative differences are often around 10% and may reach over 15% depending on a combination of intrinsic and extrinsic input parameters such as low activation energy and high-temperature of measurement, respectively. An analytical equation that expresses the relative difference between activation energy calculated from both equations is also presented and discussed.

Sensitivity analysis of four crop water stress indices to ambient environmental conditions and stomatal conductance

Crop water stress indices (CWSIs) quantify plant water status based on measurement of plant temperature. The goal of CWSI formulation is to normalize measured leaf temperatures based on reference temperatures to remove sensitivity to ambient environmental conditions (e.g., air temperature, humidity, radiation), while retaining sensitivity to plant water status as reflected by stomatal conductance. This study sought to better understand the sensitivity of these temperatures to ambient environmental conditions, and ultimately how they influence various CWSIs. The surface energy balance was modeled to simulate the impacts of input parameter variation on leaf temperature and reference surface temperatures used to calculate four different CWSIs. The performance of the CWSIs were assessed based on their ability to maximize sensitivity to stomatal conductance while minimizing the relative sensitivity to ambient environmental conditions.The sensitivity analyses indicated that all four CWSIs performed poorly in shaded conditions, as they had relatively low sensitivity to stomatal conductance and were sensitive to all environmental parameters. Two CWSIs had high sensitivity to stomatal conductance, and low sensitivity to all environmental parameters except wind speed. None of CWSIs could remove sensitivity to all environmental parameters while retaining sensitivity to stomatal conductance.

Gyrokinetic GENE simulations of DIII-D near-edge L-mode plasmas

We present gyrokinetic simulations with the GENE code addressing the near-edge region of an L-mode plasma in the DIII-D tokamak. At radial position ρ = 0.80, simulations with the ion temperature gradient (ITG) increased by 40% above the nominal value give electron and ion heat fluxes that are in simultaneous agreement with the experiment. This gradient increase is consistent with the combined statistical and systematic uncertainty σ of the charge exchange recombination spectroscopy measurements at the 1.6σ level. Multiscale simulations are carried out with a realistic mass ratio and geometry for the first time in the near-edge. These multiscale simulations suggest that the highly unstable ion temperature gradient (ITG) modes of the flux-matched ion-scale simulations suppress electron-scale transport, such that ion-scale simulations are sufficient at this location. At radial position ρ = 0.90, nonlinear simulations show a hybrid state of ITG and trapped electron modes, which was not expected from linear simulations. The nonlinear simulations reproduce the total experimental heat flux with the inclusion of E × B shear effects and an increase in the electron temperature gradient by ∼23%. This gradient increase is compatible with the combined statistical and systematic uncertainty of the Thomson scattering data at the 1.3σ level. These results are consistent with previous findings that gyrokinetic simulations are able to reproduce the experimental heat fluxes by varying input parameters close to their experimental uncertainties, pushing the validation frontier closer to the edge region.

Comparative energy and environmental analysis of agro-pellet production from orchard woody biomass

Woody biomass has a considerable potential for energy purposes specially after densification processes which convert these materials into solid biofuels with higher energy density. This study focuses on the energy and environmental assessment of pellet production system from vine and olive grove woody biomass. The life cycle assessment (LCA) from grape and olive cultivation up to packed pellet production, ready for delivery to final users was conducted to quantify the eco-profile of agro-pellet production. The results of comparative analysis revealed that pellet production from both biomasses is dominated by cultivation phase. Vine pellet production was more dependent on chemical fertilizers specially potassium sulfate, but olive pellet production was more dependent on copper oxide pesticide. Primary energy use per MJ energy of vine pellet was greater than that of olive pellet (0.6 vs. 0.19). On the other hand, energy return ratio of olive pellet was three times of that of vine pellet (5.22 vs. 1.7). Nevertheless, olive pellet had higher environmental impacts in the forms of human toxicity, freshwater ecotoxicity and marine ecotoxicity. Consequently, sensitivity analysis investigates the impact of variation in input parameters of fertilizers, pesticides, machinery, diesel fuel, transport and pelletizing process on LCA results.

Design of high-temperature solar receiver integrated with short-term thermal storage for Dish-Micro Gas Turbine systems

Small-scale concentrated solar power plants equipped with Micro Gas Turbines (MGTs) could be an effective way for power production in the off-grid areas. One of the most relevant concerns for such no fuel-assisted systems is the solar radiation fluctuations, which reduce system performance and, in the worst cases, can damage the MGT. To overcome this issue, the solar receiver should have sufficient thermal inertia averaging the thermal power inputted in the MGT. In the present study, the design of a novel high-temperature cavity solar receiver is presented for the application in the Dish-MGT system. The receiver has been integrated with a PCM for the short-term thermal energy storage (15–30 min). The design process was based on the main parameters of the solar dish and MGT. The thermal model enables the variation of different geometrical factors and input parameters to identify the optimum receiver design. Moreover, it can be used for the evaluation of heat losses from the cavity surface and temperature distributions in the PCM. A 1D steady-state model has been developed for the heat loss calculation from the cavity and corresponding cavity surface temperature, as well as for the evaluation of number and dimensions of the MGT working fluid tubes. Furthermore, the PCM melting and the transient temperature distribution inside the PCM domain have been determined analytically with the help of a 1D thermal model. The initial design results showed that solar receiver integrated with the high-temperature PCM is a promising option for the stable outlet temperature for MGT.

A simplified physical model of negative leader in long sparks

The model of negative leader in long sparks is the first step to model the upward connecting negative leader (UCNL) from grounded objects for positive cloud-to-ground lightning. In contrast with the upward connecting positive leader, the UCNL is always stepped, which is reproduced in our model. Several assumptions are made in order to simplify the model. We assumed that the difference between the geometrical potential due to the grounding structure and that after corona formation can be used for calculating the charge in the streamer zone. The potential distribution inside the steamer zone was simplified by neglecting the negative streamers near the HV electrode (negative polarity), and the velocity of primary negative leader was set to a fixed value. Different minimum charges required to sustain the extension of the negative and positive parts of space leader prior to its connection to the primary leader were used. The model was verified using experimental datum for negative sparks in 10-m, 16.7-m and 7-m rod-plane air gap. Sensitivity of model predictions to variation in model input parameters was analyzed. The model in this paper can be used to analyze the negative leader propagation in long sparks, which will be extended to UCNL process in the future work.

Development and implementation of control of stand‐alone PMSG‐based distributed energy system with variation in input and output parameters

This work develops a combined control for a stand-alone permanent magnet synchronous generator (PMSG) working with variable source and output demand. The power circuit consists of one PMSG, driven by uncontrolled prime mover supplying load through two voltage source converter (VSC) connected through a dc link capacitor. The main objective of the control is to supply load at constant voltage and frequency, even with variation in source speed and power, and also to accommodate the change in load transients. The generator side converter control is developed in rotor flux oriented synchronously rotating reference frame, to keep the dc link voltage, of the back to back VSC, constant. The load side converter control is also developed in the synchronously rotating reference frame to supply load at constant voltage and frequency. The developed combined control strategy is implemented in MATLAB/SIMULINK environment and found to be successful under all considered operating conditions. The theoretical findings are experimentally verified with a real-time prototype.

Economic and clinical benefits of early identification of acute kidney injury using a urinary biomarker

Purpose: To evaluate the budget impact of adding a diagnostic test of tissue inhibitor of metalloproteinase 2 and insulin-like growth factor binding protein 7 ([TIMP-2]·[IGFBP7]), which identifies patients at risk of moderate-to-severe acute kidney injury (AKI), to the current standard of care (SOC) in a hospital setting.Materials and methods: A budget impact model (2017 USD) was developed from the perspective of a hypothetical US hospital system serving 10,000 inpatients annually. The model estimated the impact of assessing the risk of AKI using SOC vs a combination of SOC and the US Food and Drug Administration-approved assay [TIMP-2]·[IGFBP7] over a 1-year period. Potential cost implications were assessed using estimates for payer mix among patients, diagnostic efficacy, and patient healthcare resource utilization. The model also considered provider adoption rates and the estimated costs of [TIMP-2]·[IGFBP7].Results: Compared to SOC alone, adding [TIMP-2]·[IGFBP7] to SOC was associated with a $1,855 reduction in uncompensated care per patient tested, which, after accounting for the additional costs of the test ($277), resulted in net savings of $1,578 per patient tested. The findings were robust to input parameter variations, as demonstrated by deterministic and probabilistic sensitivity analyses. In the probabilistic sensitivity analyses, net cost savings to the hospital ranged from $50,308–$3,971,514, or $101–$7,943 per tested patient (mean = $1,710; 95% confidence interval = $1,691–$1,729).Conclusions: The introduction of [TIMP-2]·[IGFBP7] as a novel tool in the identification of AKI risk may result in considerable cost savings from a hospital perspective under this model’s base-case assumptions. Further prospective studies are needed to confirm these findings in a real-world setting.Key points for decision makersAn economic model was constructed to determine the budget impact of adding a diagnostic test ([TIMP-2]·[IGFBP7]), which identifies patients at risk of moderate-to-severe acute kidney injury, to the current standard of care (SOC) in a hospital setting.According to the present model, the use of [TIMP-2]·[IGFBP7] to identify acute kidney injury risk may reduce costs for hospitals by ∼$1,578 per patient tested.

Wire electrical discharge machining of AZ91 magnesium alloy; investigation of effect of process input parameters on performance characteristics

Magnesium alloys have wide application in aerospace and automotive industries due to their high strength to weight ratio and desired mechanical properties. In this present research, the effects of three input parameters of the wire electrical discharge machining (WEDM) process, including pulse on time, pulse current, and servo feed rate were studied on the performance characteristics namely; material removal rate, kerf width, and surface roughness during machining of AZ91 magnesium alloy. This research is the first comprehensive study of the electrical discharge machining of magnesium alloys and aims to analyses the machinability and behavior of materials with low melting point and high thermal conductivity during WEDM. For this purpose, 15 experiments were designed by the design of experiments technique. Using response surface methodology, mathematical models were developed and the contribution percentage of each variable input parameter on output parameters was found. Analysis of variance results revealed that pulse on time and pulse current have the most effect on process output parameters, respectively, while the effect of the servo feed rate was insignificant. The experimental results showed that the material removal rate and the kerf width during the WEDM of magnesium is considerably higher than hard materials and it can be reached to about 180 mm3 min−1 while kerf width and surface roughness are about 0.450 and 4.683 μm, respectively. Despite the high cutting rate, the surface roughness is appropriate and comparable to hard materials, indicating high machinability of magnesium alloys by WEDM. To study the surface topography and microstructural changes, atomic force microscope, scanning electron microscope and EDX analysis have been used. SEM micrographs show that the number of microcracks, indicating the surface damage, is low in the machined surface which shows WEDM capability in producing non-damaged work surfaces. The maximum recast layer thickness is about 6.91 μm and minimum is 3.09 μm.