Modified PSO algorithm for multi-objective optimization of the cutting parameters

Economic profit of machining is essentially based on the optimal selection of cutting parameters. In this paper, a multi-objective particle swarm optimization approach is introduced to optimize the cutting parameters in turning processes: cutting speed, feed rate and cutting depth. The proposed model presents the problem in form of a multi-objective problem with production rate and used tool life objectives and has a set of constraints that represent the important limitations to be satisfied. To obtain the non dominated solutions and build the Pareto front graph, a modified dynamic neighborhood particle swarm optimization (DNPSO) technique is used. In addition, a fuzzy-based mechanism is employed to extract the best compromise solution. The results on an illustrative sample reveal the capabilities of the proposed DNPSO approach to generate well-distributed Pareto optimal solutions. Comparison with multi-objective deterministic approach (Min?CMax) shows the superiority of the proposed approach and confirms its potential for solving multi-objective problems.     

Innovative methodology to extract dynamic compact thermal models: Application to power devices

This paper presents a new and innovative methodology for power components manufacturers to generate accurate boundary condition independent dynamic Compact Thermal Models (“BCI” DCTMs). The originality of this methodology is summarized by taking into account the thermal behavior of electronic components containing several cooling surfaces, and representing the non-linear properties of materials, while keeping a simple and recurring structure of generated models. Moreover, the proposed method makes it possible to obtain DCTMs with a limited number of measurements or 3D thermal simulations. The methodology to construct the DCTM is based on the construction of an equivalent thermal RC network. The precision of the RC thermal network is improved using variable resistances and capacitances related to the heat fluxes so that the compact model can adapt automatically with boundary conditions.     

Predictor–corrector for non-linear differential and integral equation with fractal–fractional operators

Engineering with Computers - Fractal–fractional differential and integral operators have been recognized recently as superior operators as they are able to depict physical problem with both...     

Evidence of a new dechlorinated ochratoxin A derivative formed in opossum kidney cell cultures after pretreatment by modulators of glutathione pathways: correlation with DNA-adduct formation

Ochratoxin A (OTA), a nephrotoxic mycotoxin probably implicated in human Balkan endemic nephropathy and associated urothelial tumors, induces renal carcinomas in rodents and nephrotoxicity in pigs. OTA induces DNA-adduct formation, but the structure of the adducts and their role in nephrotoxicity and carcinogenicity have only partly been elucidated. In vivo, 2-mercaptoethane sulfonate (MESNA) protects rats against OTA-induced nephrotoxicity but not against carcinogenicity, indicating two different mechanisms leading to nephrotoxicity or carcinogenicity. To better understand how DNA-adduct could be generated, opossum kidney cells (OK) have been treated by OTA alone or in presence of several compounds such as MESNA or N-acetylcysteine (another agent that, like MESNA, reduces oxidative stress by increasing of free thiols in kidney), buthionine sulfoximine (BSO) (an inhibitor of glutathione-synthase), and alpha amino-3-chloro-4,5-dihydro-5-isoxazole acetic acid (ACIVICIN) (an inhibitor of gamma glutamyl transpeptidase). Cytotoxicity of OTA on OK cells was evaluated by applying the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. None of the listed agents diminished OTA cytotoxicity significantly; ACIVICIN even increases OTA cytotoxicity. In contrast, analysis of the HPLC profiles of OTA metabolites produced during these incubations indicated that the pattern, the quantity of metabolites, and the nature of the derivatives were modulated by these agents. Ochratoxin B (OTB), open-ring ochratoxin A (OP-OA), 4 hydroxylated OTA, 10 hydroxylated OTA, OTA without phenylalanine, OTB without phenylalanine, and a dechlorinated OTA metabolite could be identified by nano-ESI-IT-MS.     

Binary-Structured Si Surface Modification by an Alkaline Treatment: Application to Poly(3,4-Ethylenedioxythiophene)-Poly(Styrene Sulfonate)/Silicon Heterojunction Solar Cells

Silicon - In recent years, silicon-organic hybrid solar cells have attracted tremendous research attention owing to their low production cost and high performance. In the present work, tapered...     

A Comparative Study on Scaling Capabilities of Si and SiGe Nanoscale Double Gate Tunneling FETs

Silicon - In the last few years, an accelerated trend towards the miniaturization of nanoscale circuits has been recorded. In this context, the Tunneling Field-Effect Transistors (TFETs) are...     

Preparation and luminescence properties of novel K2ZnP2O7: Mn2+ green phosphor

Novel green-emitting phosphors K₂Zn_1???xP₂O₇: x mol% Mn²⁺ have been successfully prepared using classical solid-state reaction method in air atmosphere, doped by different Mn²⁺ ion contents, namely x?=?0.5, 1, 1.25 and 1.5 mol%. The samples were characterized by the thermogravimetric (ATD/ATG/DSC), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), steady and time-resolved photoluminescence techniques. It was found that all K₂Zn_1???xP₂O₇: x mol% Mn²⁺ samples crystallize in the tetragonal phase with P4₂/mnm space group. Upon 425 nm excitation, K₂ZnP₂O₇: Mn²⁺ exhibits an intense broad green asymmetric emission band peaking at 520 nm, owing to the ⁴T₁→⁶A₁(⁶ S) transition of Mn²⁺ ion in K₂ZnP₂O₇. In addition, it is suggested that Mn²⁺ ions occupy more than one symmetry site in the host K₂ZnP₂O₇. The optimal Mn²⁺ ion concentration in K₂ZnP₂O₇:Mn²⁺ phosphor is 1 mol % and with the lifetime 9.81 ms.

     

ANFIS-based approach to studying subthreshold behavior including the traps effect for nanoscale thin-film DG MOSFETs

A fuzzy framework based on an adaptive network fuzzy inference system(ANFIS) is proposed to evaluate the relative degradation of the basic subthreshold parameters due to hot-carrier effects for nanoscale thin-film double-gate(DG) MOSFETs.The effect of the channel length and thickness on the resulting degradation is addressed, and 2-D numerical simulations are used for the elaboration of the training database.Several membership function shapes are developed,and the best one in terms of accuracy is selected.The predicted results agree well with the 2-D numerical simulations and can be efficiently used to investigate the impact of the interface fixed charges and quantum confinement on nanoscale DG MOSFET subthreshold behavior.Therefore,the proposed ANFIS-based approach offers a simple and accurate technique to study nanoscale devices,including the hot-carrier and quantum effects.