Levent Aydin

Izmir Katip Celebi University · Mechanical Engineering

The main goal of this study is to introduce a modified approach to the modeling-design-optimization triple procedure for cutting pure titanium. The manufacturing process is selected as wire electric discharge machining. To achieve a smooth cutting operation of the pure titanium plate (grade 2), the independent cutting parameters, peak current, puls...

The surface finish, dimensional, and geometrical tolerances of the machined workpiece are all influenced by machine tool vibration. This paper aims to minimize the acceleration during cast iron processing on a turning machine by using Stepwise Neuro Regression modeling and stochastic optimization methods. The data set regarding the turning process...

This study intends to optimize the electromagnetic interference (EMI) shielding effectiveness of multi-walled carbon nanotubes/polyvinyl alcohol (MWCNTs/PVA) composite nanofibers based on multiple nonlinear neuro-regression analysis. The effect of MWCNTs content, thickness, and frequency on the shielding properties of MWCNTs/PVA nanofibers has been...

In recent years, the use of hybrid composites, in which natural fibers combine with synthetic fibers, in place of composite structures consisting only of synthetic fibers has become increasingly popular due to growing environmental concerns and the need to develop sustainable, more lightweight, recyclable materials required for engineering applicat...

Welding is a reliable procedure used to join the same and different types of materials. Residual stress resulting from local heating and subsequent rapid cooling during welding affects weld quality. Therefore, it is crucial to determine the size and distribution of residual welding stresses. This study aims to minimize residual stress in welding op...

Redundancy resolution techniques have been widely used for the control of kinematically redundant robots. In this work, one of the redundancy resolution techniques is employed in the mechanical design optimization of a robot arm. Although the robot arm is non-redundant, the proposed method modifies robot arm kinematics by adding virtual joints to m...

TiO2 is one of the most common materials for photocatalytic applications due to its stability, affordability, and photoactive efficiency. However, it has some drawbacks, such as limited solar radiation response and quick recombination of excitons. Using graphene could be one of the methods to enhance the photocatalytic properties of TiO2. This stud...

In this chapter, Vegetable―Synthetic Hybrid Fiber Laminated Composites problems will be designed optimally in terms of high buckling resistance and low weight. Optimization problems will be solved with mixed-integer programming approach. In order to achieve this challenge, the performance of (i) non-hybrid vegetable (ii) non-hybrid synthetic (iii)...

Simultaneous analysis of buckling resistance and first ply failure behavior for synthetic and vegetable fiber-reinforced composites have been evaluated. The Modified Nelder-Mead Algorithm has been used to find the optimum buckling loads, and the failure criteria are selected to find the failure loads. The highlighted point in the present study is t...

The present study aims to design stacking sequences of dimensionally stable symmetric balanced laminated carbon/epoxy composites, with different numbers of layers, with a low coefficient of thermal expansion and high elastic moduli. To avoid excessive interlaminar stresses in the composites, the contiguity constraint for plies is also taken into co...

In this study, a new hybrid modeling optimization approach is presented for choosing the best installation location of a biogas power plant. This approach was evaluated in a case study for Manisa province in Turkey. First, the animal waste potential in Manisa was determined. By examining the biogas potential in Manisa, the mathematical model of the...

In this study, it is intended to optimize a high-velocity impact case of a composite plate. The case selected from literature focused on the failure response of advanced carbon–carbon (C/C) composites under high-velocity impacts. Based on the stochastic optimization method, three unique models are introduced within the present study's scope as dime...

This paper presents a comparative study on the burst pressure performance of aluminum (Al) liner for Type-III composite overwrapped pressure vessels (COPVs). In the analysis, the vessels were loaded with increasing internal pressure up to the burst pressure level. In the analytical part of the study, the burst pressure of the cylindrical part was p...

In this study, the stacking sequence design problems of 20-layered symmetrically balanced natural and synthetic laminated composite plates with varying aspect ratios (0.25–2) are investigated using the modified differential evolution method. Regarding this, the performance of (i) natural-natural, (ii) natural-synthetic, (iii) synthetic-synthetic fi...

In this study it is intended to optimize a high velocity impact case of a composite plate. The case is selected from the literature based on its dataset properties (e.g. amount of inputs and outputs, number of tests, physical relations with real life situations and relations between the properties studied on). The base study focused on failure resp...

Friction stir welding (FSW) is an important solid-state joining technique and has been employed in automotive, aerospace and marine industries to join aluminum, zinc, magnesium and copper alloys. In this regard, the main goal of the present study is to maximize the tensile strength of friction stir welded AA7039 aluminum alloy joints by considering...

Drilling operation is one of the primary machining processes in manufacturing of functional components. In this study, optimization of drilling process has been achieved using neuro-regression analysis. In the analysis, the effect of design parameters, namely, temperature, drill bit velocity and the feed rate of the drill bit on the mechanical stre...

Two-stage compression and intercooling are one of the enhancements made to refrigeration systems to increase efficiency and reduce the size of installations. When engineers design cooling machines, the goal is not just sizing but also to insure their optimum operation. Therefore, this leads to system optimization. Some design-optimization studies b...

In this study, a new design strategy with a systematic optimization process is proposed for the preparation of magnetite cross-linked tyrosinase aggregates (MCLTA) by using the concentration of magnetite nanoparticle, glutaraldehyde and tyrosinase enzyme as design variables. A comprehensive study on multiple non-linear neuro-regression analysis has...

A novel design optimization strategy is proposed to enhance the analytical performance of a biosensor by taking into consideration the constructional and experimental parameters as design variables. A detailed study on multiple nonlinear neuro-regression analysis has been performed methodically in order to overcome the insufficient approaches on mo...

In the present study, crashworthiness optimization of the vehicle body subjected to a frontal collision is considered. Experimental data used in this study are taken from another paper in which authors utilize meta-modelling with response surface methodology. The effect of the thickness of parts of the 1996 Dodge Neon vehicle at collision time on t...

Friction deposition is a vital manufacturing technique used in surface coating, jointing, and additive manufacturing applications. As with coating technologies, materials with superior properties can be deposited onto the surfaces of ones with poor physical or chemical properties. In this technique, process parameters such as friction pressure, mec...

Polycaprolactone (PCL) is an e biodegradable polymer used in artificial tissue production. Tissue scaffolds with PCL produced by different techniques essential are used in the treatment of bone tissue. Among the production techniques, electrospinning is of interest in the production of a mechanically robust porous tissue scaffold. To produce the de...

Electrochemical biosensors based on quantum dots (QDs) have been used for medical, environmental, and food analysis applications due to their unique characteristics, such as high electron transfer ability, large surface area, good interfacial properties, applicability for surface modification, and excellent biocompatibility. All of these characteri...

In this study, the main objective is to minimize the failure index of a cylindrical laminated composite hydrogen storage tank under internal pressure. The first step is to obtain the distribution of stress components based on Classical Laminated Plate Theory (CLPT). The second is to evaluate the burst pressure of the tank according to three differe...

Stacking sequence design and optimization of 64 layered symmetric-balance graphite/epoxy laminated composite have been performed. The optimization problems aim to find the optimum stacking sequence maximizing the critical buckling load by single objective optimization approach. Differential Evolution (DE) and Simulated Annealing (SA) optimization a...

In the literature, it is proved that grooved pipe models are thermally more efficient than the smooth pipe model. Different than the previous studies in which the groove dimensions are constant along the pipe, we study the effect of groove radius and the gap between adjacent grooves on the local heat transfer coefficients using computational fluid...

Different than the previous studies in which the groove dimensions are constant along the pipe, we study the effect of groove radius and the gap between adjacent grooves on the local heat transfer coefficients using computational fluid dynamics (CFD) software. The grooved section consists of three subsections to see the effects of groove dimension...

Ecological approach in automotive, aerospace and marine industries have stated that natural fibers (especially flax) can be used as alternative reinforcing materials to glass fibers because of their inherent good vibration and cost performances. In this regard, the present paper is an attempt to show the usage of flax fiber as an alternative to E-g...

This paper demonstrates finding the PID controller parameters which are used to acquire the desired settling time of the horizontal and vertical position variables of the Twin Rotor experiment setup. Modeling and optimization processes have been achieved based on multiple nonlinear regression analysis and Differential Evolution algorithm, respectiv...

It has been shown that grooved pipes are thermally more efficient than the smooth pipes. Compared to rectangular, trapezoidal and other groove geometries, the circular ones are proved to be the most efficient in terms of heat transfer. Different than the previous studies in which the groove dimensions are constant along the pipe, we study the effec...

In design of engineering structures, engineers have considered deflection, buckling load, resonance frequency, impact resistance, fatigue life and dimensionally stability as mechanical design requirement for composite structures. Especially, in dynamical engineering systems, fundamental frequency is an important issue in order to prevent resonance...

The present paper deals with the prediction capability of theoretical and empirical models on thermal conductivity coefficient (TCC) of red mud/polypropylene composites. Red mud is known as an industrial waste material occurs during the production of alumina by Bayer's process. The characterization analyses of the red mud particulates have been car...

The thinning of the silicon wafers and the smoothening of the surface are carried out by grinding and lapping processes. The lapping process is especially preferred to produce less surface damage of the silicon wafer in the production of high-efficiency solar cells. In this process, the surface roughness of the sample is the most influential parame...

Today, largest energy production relies on fossil fuels. However, it is expected that fossil fuels will not be main energy source in the future due to their disadvantages such as nonrenewable feature and huge emissions of greenhouse gases. Regarding of these facts, the researchers focus on to produce alternative energy resources and hydrogen is stu...

Systematic cutting process design and optimization problems are studied for surface roughness minimization by stochastic algorithms. As the experimental background of the study, n-type single crystalline silicon (Si) ingot are cut into Si wafer with a thickness of 375 µm using a wire saw machine. In order to optimize the cutting parameters successf...

The objective of this part is to emphasize the context in which the mechanics of fiber composites is examined. Constitutive equations describing the stress-strain relations are introduced. Micromechanics and macromechanics approaches for analysis are well established. Since interfacial mechanics of composites is of primary importance in discussing...

Because of material anisotropy in fiber-reinforced composites, design, and optimization processes do become very important and needed more complex analysis compared with isotropic materials. Therefore, it cannot be achieved by only sizing the cross-sectional areas and thickness of the members. In these cases, design process for laminated composites...

zet Boyutsal kararlı malzemelerin tasarımı, teleskop, uydu gibi uzay ve havacılık yapıları için önemli bir konudur. Bu bağlamda, tabakalı kompozit malzemeler uzay yapıları gerekliliklerini matematiksel optimizasyon metotlarının kullanımı ile karşılayabilir hale gelmektedir. Bu çalışmanın amacı, düşük ısıl genleşme katsayısı ve yüksek elastisite mod...

Optimum Design of Type-III Hydrogen Storage Tanks

Ulexite mineral, which has many application fields such as glass, ceramics and chemical industry, generally is used as thermal resistance filler material in polymer composite applications. In the present study, ulexite/polypropylene composites were produced with three different filler ratios 10%, 20% and 30% (weight). Thermo-gravimetric analyzes of...

Membrane adsorbers are promising candidates for the efficient and effective removal of heavy metals in waste water due to their unattainable adsorption and filtration capabilities. In the present study, zeolite nanoparticles incorporated polysulfone (PSf10) membrane was synthesized by means of non-solvent induced phase separation technique for the...

Dimensionally stable material design is an important issue for space structures such as space laser communication systems, telescopes, and satellites. Suitably designed composite materials for this purpose can meet the functional and structural requirements. In this paper, it is aimed to design the dimensionally stable laminated composites by using...

In this study, an optimization procedure is proposed to find the optimum stacking sequence designs of laminated composite plates in different fiber angle domains for maximum buckling resistance. A hybrid algorithm combining genetic algorithm and trust region reflective algorithm is used in the optimization to obtain higher performance and improve t...

Longitudinal natural vibration frequencies of rods (or bars) with variable cross-sections are obtained from the exact solutions of differential equation of motion based on transformation method. For the rods having cross-section variations as power of the sinusoidal functions of ax+b, the differential equation is reduced to associated Legendre equa...