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Mechanistic Models for prediction of cutting forces and power consumption considering chip Geometry
No full textA novel approach for modeling and simulation of cutting force and power consumption in relation to chip geometry has
been proposed in end milling of AISI D2 steel. It is carried out in two stages: experimental work and finite element method based numerical simulation. In the first stage, experiments are conducted on the AISI D2 steel at two levels of spindle rotational speed, axial depth of cuts and four levels of feed per tooth using 10 mm and 8 mm diameter mill cutters. Cutting forces and amplitude of cutter vibration are measured in X and Y directions. Mechanistic models in terms of chip geometry and cutting force coefficients are developed to predict cutting forces and power consumption relative to chip geometry at 30, 60 and 90 of cutter rotation. In the second stage, numerical simulation is carried out
to predict cutting forces and power consumption relative to chip geometry at 30, 60 and 90 of cutter rotation and compared with estimated values of cutting forces and power consumption. The maximum error between the two approaches for the cutting forces in X and Y directions and power consumption is estimated as 10.80%, 8.33% and 7.70% respectively. At spindle rotational speed of 2000 rpm, 0.3 mm of axial depth of cut and 50 mm of feed per tooth, the cutting forces and cutting power consumption are found minimum
Impact and Shear behavior of PLA/12%Cu reinforced composite filament printed at different FDM conditions
No full textThe advantages of metal powder in the Polylactic Acid (PLA) matrix for strengthening have attracted interest among the
researchers. An attempt was made to use the advantages of copper (Cu) as the reinforcing component in the PLA matrix.
After a few series of exams, copper with weight percentages of 12 in the PLA matrix was reported to be an appropriate
composition. The PLA-Cu composite flament with 12% Cu was successfully manufactured using hot extrusion. 1.75–mmdiameter extracted composite flament was built according to the ASTM standard for shear and impact testing under various
Fused Deposition Model (FDM) conditions. The efects of nozzle temperature, bed temperature, and layer height on diferent printing conditions were examined. The efect of the FDM parameters during impact load conditions was in the order of
the nozzle temperature, bed temperature, and layer height. The efect of FDM machining conditions on the shear depends
primarily on the thickness of the layer. The shear test is minimally infuenced by the extrusion temperature. Analysis of the topography of the fracture surface reveals that a fracture surface is a form of plastic deformation and that the crack initiated from the layer limit. The dislocations of the Cu particles through the slide advances toward the failure. An elevated extrusion temperature reduces ductility. Diferent surface profle settings are analyzed using 3D optical microscopy
Assessing the effect of FDM processing parameters on mechanical properties of PLA parts using Taguchi method
No full textFused deposition modeling (FDM) is a fast-expanding additive manufacturing technique for fabricating various polymer components in engineering and medical applications. The
mechanical properties of components printed with the FDM method are influenced by several process parameters. In the current work, the influence of nozzle temperature, infill density, and printing speed on the tensile properties of specimens printed using polylactic acid (PLA) filament was investigated. With an objective to achieve better tensile properties including elastic modulus, tensile strength, and fracture strain; Taguchi
L8 array has been used for framing experimental runs, and eight experiments were conducted. The results demonstrate that the nozzle temperature significantly influences the tensile properties of the FDM printed PLA products followed by infill density. The optimum processing parameters were determined for the FDM printed PLA material at a nozzle temperature of 220C, infill density of 100%, and printing speed of 20 mm/s
SAR IMAGES CHANGE DETECTION BASED ON ADWT TECHNIQUE USING MFO ALGORITHM
No full textIn this article a novel technique is introducing for performing the image fusion. As it is very familiar that more image information could be brought up by using image fusion process. Filter coefficients have been chosen in the DWT (Discrete Wavelet Transform) filter bank to perform DWT through optimization algorithm. The process of selecting filter coefficients through optimization process is known as ADWT (Adaptive Discrete Wavelet Transform). In this regard, satellite images with active sensor have been employed where these images are captured at same geo location but at different timings. Consequently, by satisfying the orthonormal properties filter coefficients have been chosen through Math-Flame Optimization (MFO) Algorithm. After performing the image fusion based on DWT by
using optimized filter coefficients, the resultant image has been segmented with FCM-Clustering technique. Segmented image compared with the ground truth image. In this process input images are merged based on Particle Swarm Optimization (PSO) algorithm, Math-Flame Optimization (MFO) and Ant Lion Optimization Algorithm (ALO). Finally, the effectiveness of the proposed method is measured in terms of sensitivity, precision, selectivity, FDR and Accuracy
Structural, Mechanical and Magnetic Characterization of Rare Earth Double Doped SrBi2Nb2O9 lead Free Ceramics
No full textLead free dielectric materials of Strontium Bismuth Niobate SrBi2Nb2O9 (SBN) and rare earth double doped SrBi1.8Pr0.1Gd0.1Nb2O9 (SBPGN), SrBi1.8Pr0.1Y0.1Nb2O9 (SBPYN), SrBi1.8Eu0.1Gd0.1Nb2O9 (SBEGN) and SrBi1.8Eu0.1Y0.1Nb2O9 (SBEYN) were prepared by
two-stage solid-state reaction route. The XRD studies have confirmed the formation of single-phase orthorhombic crystal structure. The microstructural analysis showed the
formation of plausible needle shaped grains in the prepared ceramics. The FTIR study was used to investigate the effect of preparation and doping processes on the band intensities of the spectra. Mechanical studies showed that SBEGN and SBEYN ceramics exhibited mild wear (< 10-6 mm3 /Nm) compared to others. The low friction coefficient values of SBPYN (0.044), SBEGN (0.058) and SBEYN (0.002) to that of SBN necessitate lattice strain in these materials. The VSM studies on the rare earth double doped SBN ceramic materials confirmed the induction and existence of magnetic order in SBPGN and SBEGN
Sensory evaluation of microwave assisted ultrasound treated soymilk beverage using fuzzy logic
Get PDFThis study was centered to develop an acceptable quality of soymilk based flavoured beverage based on sensorial characterization. The beverage contains an array of health beneficial compounds such as phytosterols, isoflavones, and flavonoids. These compounds are attributed to prevention of osteoporosis, cancer, heart disease, and reduction of cholesterol. Moreover, this flavoured beverage is essential for vegan consumers and lactose intolerant than normal consumers. The sensory examination of nine soymilk based flavoured beverages (S1, S2, S3, S4, S5, S6, S7, S8, and S9) was done to maximize the acceptability. Lastly, ranking of the different samples according to their sensory qualities and also to rank attributes of general quality. After review of the sensory parameters collected from a jury of 26 jurors, the rating of flavored beverage samples based on soymilk was followed S2> S9> S1> S4> S8> S7> S6> S5> S3. The ranking for the attributes of general quality was Taste > Mouthfeel >After Taste > Color >Aroma
Characterization of electrospun polyurethane/polyacrylonitrile nanofiber for protective textiles
Get PDFA system of polyurethane (PU) and polyacrylonitrile (PAN) with a polymer composition of 60:40 electrospun nanofibrous web has been developed as barriers to pesticides liquid (Dimethoate) penetration in protective clothing systems for agricultural workers. Barrier performance of different polymer compositions of PU and PAN layered systems has been evaluated with different areal densities of electrospun web ranging from 0.5 to 3 g/m2. This was done to improve the barrier performance of a nanofiber against a pesticide liquid. In this process, an ultra-thin layer of PU and PAN has been taken in the ratio of 60:40 and its top it is coated with polyvinylidene fluoride (PVDF). Application of PU and PAN web with PVDF and PU has significantly improved its effectiveness which has been measured when accessing the overall comfort performance of a nanofiber which includes parameters like air permeability and water vapor transmission within a layered system. Further, it is observed that the electrospun areal density has been altered due to the effect of air permeability and because of the penetration of the pesticide liquid. On other hand, the polymer compositions also affect the air permeability and rate of penetration of pesticides. It was observed that the electrospun web area has a massive impact on a web area density which reduces a pore size distribution when web area increases. Increasing the percentage of polyacrylonitrile with thermoplastic polyurethane the penetration is reduced without affecting the moisture vapor transition and which had a significant effect on air permeability. Hence PU and PAN along with PVDF nanofibrous mat have a prospective application in agro-textile industries
Assessment of risk of depression and diabetes among overweight and obese subjects with unsuccessful efforts to reduce body weight: Observation from clinical trial participants of weight loss intervention
Get PDFPaucity of data in context to depression and diabetes among obesity (OB) or overweight (OW) subjects with unsuccessful efforts to reduce body weight is unclear. Considering this, we evaluated the relationship between depression and diabetes risk among those populations. The vital and biochemical parameters, including lipid profile, homeostatic model assessment, were measured for eligible screened subjects who participated in the trial of weight loss intervention at first visit. Risk associated with depression and type-2 diabetes was assessed by self-reported Patient Health Questionnaire scale and American Diabetes Association diabetic risk score respectively. In our study, out of
165 individuals, 59 (35.75%) were OW and 106 (64.25%) were OB, as per the World Health Organization criteria. The OW and obesity males have greater risk of pre-diabetes or diabetes (odds ratio: 4.55% and 3.15%, 95% confidence intervals: 1.45–14.21 and 1.33–7.52) (p = 0.009 and 0.008). The body mass index (BMI) is strongly associated with depression and diabetes (p = 0.0001*). Insignificant association was observed between insulin resistance/diabetic among the depressive obese subjects (p > 0.05). Obesity or OW were found to link with risk of depression and the abnormal BMI was substantially amplifying the risk of diabetes
Study on molecular interactions of binary mixtures of 2,6-dimethyl cyclohexanone with substituted anilines at T = (303.15 to 313.15) K through thermodynamic properties and FT-IR Spectra and correlation with the Jouyban-Acree model
No full textThe densities ( r ), speeds of sound (u) and viscosities (h) of binary mixtures of 2,6-dimethylcyclohexanone (2,6-DMCY) with substituted anilines (N,N-dimethylaniline (N,N-DMA), N-methylaniline (N-MA)) and aniline (A) measured over the entire
composition range at temperatures (303.15, 308.15 and 313.15) K and 0.1MPa. Using the experimental data, the excess volume, excess isentropic compressibility, and deviation in viscosity, excess partial properties of the components at infinite dilution
were calculated. Prigogine-Flory-Patterson (PFP) theory is applied to identify the predominant molecular interaction. Jouyban-Acree model, results are discussed in terms of mean relative deviation (MRDs) and individual relative deviation (IRD)
between calculate and experimental densities, speeds of sound and viscosities as an accuracy criterion. A good agreement is observed among the excess parameters and FT-IR spectroscopic propertie
Impact and Shear Behavior of PLA/12% Cu Reinforced Composite Filament Printed at Different FDM Conditions
No full textAbstract
The advantages of metal powder in the Polylactic Acid (PLA) matrix for strengthening have attracted interest among the
researchers. An attempt was made to use the advantages of copper (Cu) as the reinforcing component in the PLA matrix.
After a few series of exams, copper with weight percentages of 12 in the PLA matrix was reported to be an appropriate
composition. The PLA-Cu composite flament with 12% Cu was successfully manufactured using hot extrusion. 1.75–mm�diameter extracted composite flament was built according to the ASTM standard for shear and impact testing under various
Fused Deposition Model (FDM) conditions. The efects of nozzle temperature, bed temperature, and layer height on difer�ent printing conditions were examined. The efect of the FDM parameters during impact load conditions was in the order of
the nozzle temperature, bed temperature, and layer height. The efect of FDM machining conditions on the shear depends
primarily on the thickness of the layer. The shear test is minimally infuenced by the extrusion temperature. Analysis of the topography of the fracture surface reveals that a fracture surface is a form of plastic deformation and that the crack initiated rom the layer limit. The dislocations of the Cu particles through the slide advances toward the failure. An elevated extrusion temperature reduces ductility. Diferent surface profle settings are analyzed using 3D optical microscop