Bogdan Bedelean

Dr. Bogdan Bedelean

orcid

Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 February 2018 in International Journal of Thermal Sciences
Verified
Journal Article
Closed access
DSDaniela Sova
Daniela Sova
MPMihaela Porojan
Mihaela Porojan
Bogdan BedeleanBogdan Bedelean
Bogdan Bedelean
GHGabriela Huminic
Gabriela Huminic

11 September 2024 in Forests
Verified
Journal Article
Open access
PDF file
Bogdan BedeleanBogdan Bedelean
Bogdan Bedelean
MIMihai Ispas
Mihai Ispas
SRSergiu Racasan
Sergiu Racasan
Many factors (material properties, drill bit type and size, drill bit wear, drilling parameters used, and machine-tool characteristics) affect the efficiency of the drilling process, which could be quantified through the delamination factor, thrust force, and drilling torque. To find the optimal combination among the factors that affect the desired responses during drilling of wood-based composites, various modelling techniques could be applied. In this work, an artificial neural network (ANN) and response surface methodology (RSM) were applied to predict and optimize the delamination factor at the inlet and outlet, thrust force, and drilling torque during drilling of prelaminated particleboards, medium- density fiberboard (MDF), and plywood. The artificial neural networks were used to design four models—one for each analyzed response. The coefficient of determination (R2) during the validation phase of designed ANN models was among 0.39 and 0.96. The response surface methodology was involved to reveal the individual influence of analyzed factors on the drilling process and also to figure out the optimum combination of factors. The regression equations obtained an R2 among 0.88 and 0.99. The material type affects mostly the delamination factor. The thrust force is mostly influenced by the drill type. The chipload has a significant effect on the drilling torque. A twist drill with a tip angle equal to 30° and a chipload of 0.1 mm/rev. could be used to efficiently drill the analyzed wood-based composites.

1 July 2022 in Forests
Verified
Journal Article
Open access
PDF file
Bogdan BedeleanBogdan Bedelean
Bogdan Bedelean
MIMihai Ispas
Mihai Ispas
SRSergiu Racasan
Sergiu Racasan
MBMarius Nicolae Baba
Marius Nicolae Baba
Drilling is one of the oldest and most important methods of processing wood and wood-based materials. Knowing the optimum value of factors that affect the drilling process could lead both to high-quality furniture and low-energy consumption during the manufacturing process. In this work, the artificial neural network modeling technique and response surface methodology were employed to reveal the optimum value of selected factors, namely, drill tip angle, tooth bite, and drill type of the delamination factor at the inlet and outlet, thrust force, and drilling torque. The data set that was used in this work to develop and validate the ANN models was collected from the literature. The results showed that the developed ANN models could reasonably predict the analyzed responses. By using these models and the response surface methodology, the optimum values of analyzed factors were revealed. Moreover, the influences of selected factors on the drilling process of wood particleboards were analyzed.

16 November 2023 in Forests
Verified
Journal Article
Open access
PDF file
Bogdan BedeleanBogdan Bedelean
Bogdan Bedelean
MIMihai Ispas
Mihai Ispas
SRSergiu Racasan
Sergiu Racasan
Most of the parts of furniture made of medium density fiberboards (MDF) require at least one hole to be assembled. The drilling technological parameters influence the quality of holes. Factors such as tip angle of the drill bit, feed rate, type and diameter of the drill bit, and spindle rotational speed could affect the drilling process. Therefore, the right choosing of drilling parameters is a mandatory condition to improve the drilling efficiency that is expressed through tool durability, cost, and quality of the drilling. Thus, in this work, we are proposed an approach that consists in combining two modelling techniques, which were successfully applied in various fields, namely artificial neural network (ANN) and response surface methodology (RSM), to analyze and optimize the drilling process of MDF boards. Four artificial neural network models with a reasonable accuracy were developed to predict the analyzed responses, namely delamination factor at inlet, delamination factor at outlet, thrust force, and drilling torque. These models were used to complete the experimental design that was requested by the RSM. The optimum values of the selected factors and their influence on the drilling process of the MDF boards were revealed. A part of optimum combinations among analyzed factors could be used both during the drilling of the MDF boards and prelaminated wood particleboards.

1 January 2018 in BioResources
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Journal Article
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NBNicolae Badin
Nicolae Badin
Mihaela CampeanMihaela Campean
Mihaela Campean
KLKaroly Lengyel
Karoly Lengyel
MIMihai Ispas
Mihai Ispas
Bogdan BedeleanBogdan Bedelean
Bogdan Bedelean
Several potential approaches were evaluated to improve the physical and mechanical properties of 3 mm HDF panels used as door-skins. Six different composition recipes were applied by varying the ratio of hardwood-to-softwood fibers and the addition of bark. The density, surface absorption, bending strength, modulus of elasticity, and internal bond of the HDF panels manufactured on an industrial line were determined. The best performance was obtained for the recipe with 20% hardwood fibers, 80% softwood fibers, and less than 5% bark. The influence of spraying the fiber mattress before pressing, by means of water and two different release agents, was also tested. The obtained results are applicable at any HDF producer and can be used for process optimization.

16 October 2023 in Applied Sciences
Verified
Journal Article
Open access
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Bogdan BedeleanBogdan Bedelean
Bogdan Bedelean
MIMihai Ispas
Mihai Ispas
SRSergiu Racasan
Sergiu Racasan
Plywood is a wood-based composite with many applications in construction, shipbuilding, and furniture production. One of the basic plywood processing and mandatory operations is drilling. Up to now, considerable and very diverse thematic research has been recently carried out on drilling, but little of that deals with modeling of the drilling process of plywood. Therefore, in this work, the artificial neural network modeling technique and response surface methodology were applied to model and optimize the drilling process of plywood. Two artificial neural network models were developed to predict the thrust force and the drilling torque based on drill tip angle, tooth bite, and drill type. The developed ANN models were used to complete the value of responses in the experimental design, which was requested by the response surface methodology. The trust force during the drilling of plywood is significantly influenced by the drill type (helical or flat). The most significant factor that affects the drilling torque during the drilling of plywood is the tooth bite. A helical drill assures a lower minimum thrust force and drilling torque than a flat drill. The proposed method could be used as an optimization tool during the design phase of the furniture manufacturing process.