Ebubekir Koç

Fatih Sultan Mehmet Vakif Üniversitesi

The selective laser sintering process is widely used to fabricate polyamide matrix composites. Although various reinforcements are used to produce polyamide matrix composites, metallic-based reinforcements are used to improve the mechanical properties of the structure. Also, selective laser sintering process parameters significantly affect the micr...

This study presents a comprehensive experimental dataset and a novel classification model based on Deep Neural Networks to estimate surface roughness for additive manufacturing. Many problems exist due to the very complex nature of the production process. Some focus on the production planning phase, including the nesting problem under many constrai...

Unmanned aerial vehicles are expected to complete their missions even in adverse weather conditions. Overheating in the engine area may occur, particularly at high speeds due to using the full engine throttle. Another design factor that affects endurance duration and maximum takeoff weight is the weight of the unmanned aerial vehicle heat exchanger...

In this study, a novel classification model is proposed to estimate surface roughness for the parts produced in an industrial additive manufacturing technology. The proposed model focused on selective laser sintering (SLS) technology based on polyamide 12 powder applications. A comprehensive dataset is designed to simulate the production parts and...

Gear wheels, the frst examples of use in the Mesopotamian period, continue to develop with diferent forms and features together with advanced technologies. Within the scope of this study, the DMLS (direct metal laser sintering) technique, which is one of the latest technologies, was preferred as a method in the production of gears. A total of four...

Purpose The current investigation aims at observing the influence of the cooling channel on the thermal and residual stress behavior of the selective laser melting (SLM)316L uni-layer thermo-mechanical model. Design/methodology/approach On a thermo-mechanical model with a cooling channel, the effect of scanning direction, parallel and perpendicula...

The unique additive manufacturing (AM) attributes such as tool-less design, on-site fabrication, short production cycle, and complex structures fabrication can make AM market penetration deeper. The sustained improvements in AM's computational hardware and software, advanced automation, affordable equipment, and process, structural, and metallurgic...

In the production of geometries that traditional methods cannot produce, it is seen that additive manufacturing (AM) technology, which has come to the fore, has been used extensively in conformal cooling channel (CCC) applications in recent years. This study, conducted within the scope of CCC's use of applied mold cores in automotive industry plast...

Manufacturability without supports in design studies for additive manufacturing (AM) brings many advantages such as time, cost, part surface quality, and design freedom. It is thought that the geometries that can be produced without support will help the more widespread use of AM technologies. In this study, the unsupported manufacturability and ef...

Purpose The present study aims to investigate the effect of finish machining and aging processes on the surface integrity of the selective laser melted (SLM) maraging steel samples and compared them with those obtained conventionally. Design/methodology/approach Finish machining and aging were applied on the SLM and wrought maraging samples to inv...

Recurrent neural networks (RNNs) are powerful tools for learning information from temporal sequences. Designing an optimum deep RNN is difficult due to configuration and training issues, such as vanishing and exploding gradients. In this paper, a novel metaheuristic optimisation approach is proposed for training deep RNNs for the sentiment classifi...

Selective laser sintering (SLS) is a process of fabrication of three-dimensional structures by fusing powder particles using a guided laser source. The uncertainty in the mechanical properties of the SLS parts fabricated at the same time and with the same process parameters can affect the repeatability of the SLS process. A vast difference in the m...

Selective laser melting (SLM) is an additive manufacturing process to fabricate three-dimensional structures by fusing powder particles using a computer-guided laser source. The SLM process can produce lightweight bespoke designs, having high strength comparable to conventional components. However, the developed surface texture and some of the mech...

Additive manufacturing technology is an innovative and advantageous production technology in producing microchannels, heat exchangers designed in complex geometries. Process parameters developed to provide production standardization and quality standards on production results are known. The study investigates the sagging effect of downskin paramete...

Recursive Deep Models have been used as powerful models to learn compositional representations of text for many natural language processing tasks. However, they require structured input (i.e. sentiment treebank) to encode sentences based on their tree-based structure to enable them to learn latent semantics of words using recursive composition func...

This paper attempts to improve the physical and mechanical properties of selective laser sintered polyamide PA2200 components through a vibratory surface finishing process by inducing severe plastic deformation at the outer surface layers. The industrial target of additive manufacturing components is to obtain structures having surface roughness, h...

The maraging steel components fabricated using the selective laser melting process exhibit remarkable static strength. However, high pore density and large surface imperfections impede their overall mechanical and chemical performance. Thus, the components are often post‐treated with mechanical‐ and thermal‐based treatments to overcome their inhere...

Purpose The purpose of this paper is to evaluate the effect of post process combinations, e.g. hot isostatic pressing (HIP) only, HIP + T6 heat treatments, and T6 only, with different aging time, on surface properties, microstructure and mechanical properties of stress-relieved AlSi10Mg parts produced by direct laser metal sintering. Design/method...

In this study, the design, analysis, and production of an unmanned aerial vehicle (UAV) was carried out using SLS (Selective Laser Sintering) production technology. Herein, a multidisciplinary project was realized on the four different aircraft models supported by CFD analysis and the results during the taxing were compared using flow parameters. W...

In this study, unmanned aerial vehicle (UAV) design, analysis and production was made using selective laser sintering (SLS) system. Four different aircraft bodies were designed in the interdisciplinary project, one of the models was selected by comparing the computational fluid dynamics (CFD) analysis results. According to the numerical study, the...

In this study, Polymer (Primecast® 101-EOS)patterns were produced with the EOS Formiga P110 system, and these patterns were compared with conventional wax patterns using their suitability for the investment casting (IC) method. Besides, Scanning Electron Microscope (SEM) and Thermal Analysis (DSC and TGA) were applied produced to investigate the pr...

Selective laser melting (SLM) is one of the most frequently employed metal additive manufacturing methods. Various industries such as aerospace, automotive, biomedical, and tooling utilize SLM parts. Although it has a wide scope of applications, it demands a thorough understanding to supply reliable parts. Thus, process simulations are key methods...

In this work, hot isostatic pressing and subsequent T6 heat treatment, by using two different aging durations (4h and 12h), were applied to laser sintered AlSi10Mg materials to evaluate the effects of secondary process combinations on properties of DMLS AlSi10Mg alloy. Relative densities and open porosities were determined using Archimedes method....

The aim of this research is to reach a deep understanding on the effect of the process parameters of Direct Metal Laser Sintering process (DMLS) on thermal and mechanical properties (thermal conductivity, porosity and compression) of AlSi10Mg parts and resulting microstructure. In this study, a variation of the thermal, porosity and mechanical prop...

Selective laser sintering (SLS) is one of a popular method of additive manufacturing technique. In this study, PrimeCast ® was used, which is a trade name of polystyrene material of EOS Company, for the production of rapid prototyping to create investment casting patterns via the SLS process. The research examines how will be the surface roughness...

The compressive strength values of selective laser melted 22 samples of AlSi10Mg were examined statistically using the Weibull distribution function at a standard processing parameter supplied by EOS. The measured strength was found to vary in between 321 MPa to 382 MPa and 665 MPa to 883 MPa for compressive yield strength and compressive strength...

In this study, AlSi10Mg samples produced by the direct metal laser sintering (DMLS) method were applied to heat treatment with different parameters (stress relief and T6). Heat‐treated and as‐built samples were subjected to intergranular corrosion test according to BS EN ISO 11846 standard. Hardness, tensile, electrical conductivity, scanning elect...

Abstract: Birdhouse with aesthetics derived from common architecture, the geographical areas we live in and traditions can be seen as traces of cultural value from centuries before. Unfortunately, since there have been changes in architectural styles and preferences, necessities and social groups, the culture of implementing bird houses into normal...

Dear Colleagues, On behalf of Organising Committee, it is my pleasure to invite all to the Additive Manufacturing Conference Turkey (AMC TURKEY) which will bring the academia and the industry together to showpiece their cutting edge technologies at 17-18 October in Istanbul. Best Regards.

It can be said that today's civil aviation basics began to be laid in the 1950s. This date is also important as the period in which the rules are being written and at the same time, some system solutions are produced by testing the methods of cargo loading. The cargo clip used in these cargo loading systems will be the subject of our article. In th...

This paper presents the variations of surface roughness and geometrical precision of Direct Metal Laser Sintering (DMLS) parts depending on their positions on the building platform of EOS M290. A distinctive design was created to measure and compare the surface quality, dimensional accuracy, and geometrical precision. This design was built on vario...

This paper presents the variations of surface roughness and geometrical precision of Direct Metal Laser Sintering (DMLS) parts depending on their positions on the building platform of EOS M290. A distinctive design was created to measure and compare the surface quality, dimensional accuracy, and geometrical precision. This design was built on vario...

The Bees Algorithm is a new population-based search algorithm. The algorithm mimics the food foraging behaviour of swarms of honey bees. In its basic version, the algorithm performs a kind of neighbourhood search combined with random search and can be used for optimisation. The poster won two prizes: 1. “Best communication” prize for the Bees Algo...

Selective laser melting (SLM), a type of additive manufacturing (AM) process, is chosen for direct fabrication of powder-based functional metallic objects. The designing of small circular geometries or overhang surfaces built parallel to platform bed has been a subject of concern in the industrial application of SLM. This paper presents an attempt...

Selective laser melting is one of the most extensively used metal additive manufacturing method. Although many industries adopt the method, it requires a comprehensive insight to produce reliable parts. Therefore, process monitoring and process simulations are key methods to optimize the process and to reduce the product development time. This stud...

Aluminum is used in millions of different products in many diverse industries from the aerospace industry to the food industry. Owing to its low density, high strength when alloyed, high elasticity, recyclability, high resistance to corrosion, easy workability, high heat and electrical conductivity, light and heat reflectivity and environmental fri...

(In Turkish) Yapay Sinir Ağları, Kelime Vektörleri ve Derin Öğrenme Uygulamaları

(In Turkish) Evrimsel Algoritmalar ve Uygulamaları

Aluminum; It is used in millions of different products in very different industries thanks to its lightness, sufficient strength when it is alloyed, high elasticity, recyclability, high corrosion resistance, easy workability, high heat and electrical conductivity, high heat reflectivity and environmental friendliness. Casted coils produced by twin...

This paper presents the experimental work carried out to reveal the anisotropic mechanical behavior of the additive manufacturing parts introduced by the building direction in Direct Metal Laser Sintering (DMLS). DMLS is a selective laser sintering (SLS) method based on fine layers of powder materials being fused by high energy lasers to create met...

In this study, geometric forms of maraging steel dies used in aluminum extrusion were optimized by means of flow dynamics as well as surface quality and mechanical properties of the final part. Maraging steel (MS1) dies were produced by Direct Metal Laser Sintering (DMLS), a Selective Laser Sintering (SLS) method, using EOS M290. Dies were not subj...

Hybrid pseudo dynamic simulation is a technique that combines the advantages of mathematical modeling and laboratory tests. The structural system is separated into sub-structures. The components whose seismic behavior are well known, behave elastically or cannot be physically tested in the laboratory because of geometrical sizes are modelled mathem...

One of the exhausted and costly issues in extruded aluminium profiles production is the detection of scratches. Having scratches can be a big loss and wasting of time. Current methods for dealing with this problem are mostly restricted in terms of human ability, dangerous or can’t be applied during production process. This paper presents an automat...

Aluminium use has been rising steadily in recent decades. Several different industries are adapting it since its light weight, doable structure and robustness. Aluminium manufacturing runs in three ways; namely: (1) cascading, (2) extrusion and (3) drawing. Extrusion process is used to form aluminium in profiles which is one of the main semi/final-...

This paper presents the first application of the bees algorithm to the optimisation of parameters of a two-dimensional (2D) recursive digital filter. The algorithm employs a search technique inspired by the foraging behaviour of honey bees. The results obtained show clear improvement compared to those produced by the widely adopted genetic algorith...

In this thesis, a new population-based search algorithm called the Bees Algorithm (BA) is presented. The algorithm mimics the food foraging behaviour of swarms of honey bees. In its basic version, the algorithm performs a kind of neighbourhood search combined with random search and can be used for both combinatorial and functional optimisation. In...

This paper describes the first application of the Bees Algorithm to mechanical design optimization. The Bees Algorithm is a search procedure inspired by the way honey bees forage for food. Two standard mechanical design problems, the design of a welded beam structure and the design of coil springs, were used to benchmark the Bees Algorithm against...

This paper presents the design of a PID controller for a flexible single-link robot manipulator using the Bees Algorithm. The algorithm optimises the gains of the PID controller so that it can move the link to a desired position with the minimum amount of vibration during the movement. Following a description of the algorithm, the paper gives the e...

Cellular manufacturing has received increas ing attention in recent years. The key problem in d esigning cellular manufacturing systems is cell formation, which is c oncerned with grouping parts with similar processin g requirements into part families and associated machines into mac hine cells. This paper presents a novel approach fo r solving the...

The Bees Algorithm is a new population-based optimisation algorithm t hat mimics the natural foraging behaviour of a swarm of bees. In its basic version, the algorithm performs a kind of neighbourhood sear ch combined with a random search to enable it to locate the global optimum. This paper describes the application of the Bees Algorithm to a comb...

This paper describes a new application of the Bees Algorithm to the optimisation of a Support Vector M achine (SVM) for the problem of classifying defects in ply wood. The algorithm, which is a swarm-based algorithm inspired by the food foraging behaviour of honey bees, was a lso employed to select the components making up the feature vectors to be...

A new population-based search algorithm called the Bees Algorithm (BA) is presented. The algorithm mimics the food foraging behaviour of swarms of honey bees. In its basic version, the algorithm performs a kind of neighbourhood search combined with random search and can be used for both combinatorial optimisation and functional optimisation. This p...

This paper presents an application of the bees algorithm (BA) to the optimisation of neural networks for wood defect detection. This novel population-based search algorithm mimics the natural foraging behaviour of swarms of bees. In its basic version, the algorithm performs a kind of neighbourhood search combined with random search. Following a bri...

Control charts are employed in manufacturing industry for statistical process control (SPC). It is possible to detect incipient problems and prevent a process from going out of control by identifying the type of patterns displayed by the control charts. Various techniques have been applied to this control chart pattern recognition task. This paper...

Control charts are employed in manufacturing industry for statistical process control (SPC). It is possible to detect incipient problems and prevent a process from going out of control by identifying the type of patterns displayed by the control charts. Various techniques have been applied to this control chart pattern recognition task. This paper...

Researchers have been inspired by nature in many different ways. A newpopulation based search method called the Bee Algorithm (BA) is proposed. Theswarm based algorithm described in this paper goes beyond the traditional design andrevolves around mimicking the food foraging behaviour of honey bees which has beenapplied to solve unconstrained functi...