Şerafettin Ekinci | Selcuk University (Selçuk Üniversitesi) (original) (raw)

Papers by Şerafettin Ekinci

DergiPark (Istanbul University), 2017

Many studies on tractive performance of tractor tires have been carried out to solve soil-wheel i... more Many studies on tractive performance of tractor tires have been carried out to solve soil-wheel interaction problems in the last decades. The purpose of this study is to experimentally determine effects on tractive performance of radial and bias-ply drive tires at three different tire lug heights, axle loads and inflation pressures. The experiments were carried out in stubble field conditions. To obtain sufficient performance data, a new single wheel tester was designed and manufactured. Travel reduction, net traction ratio and tractive efficiency varied from 3.3% to 34.1%, 0.24 to 0.93 and from 0.27 to 0.78 respectively depending on drawbar pull. The effects of tire type, lug height, dynamic axle load and inflation pressure on tractive efficiency were found significant (P<0.01) by the performed variance analysis and LSD tests. Radial tires provide better tractive performance compared with bias-ply tires. The tractive efficiency increased especially with increasing dynamic axle load and decreased with increasing tire inflation pressure. Tire dynamic axle load was the major contributory factor on tractive performance as compared with other independent variables. For a given drawbar pull, it was observed that tractive efficiency of radial tire can be maximized by selecting appropriate levels of lug height, dynamic axle load and inflation pressure.

determine the wearing properties of nitrided and non nitrided steel. The proposed Fuzzy Expert Sy... more determine the wearing properties of nitrided and non nitrided steel. The proposed Fuzzy Expert System approach helps the user and the manufacturer to forecast the wearing properties of nitrided and non nitrided steel under specified laboratory conditions. Surfaces of the engineering components are often nitrided for improving wear, corosion, fatigue specifications. A major property of nitriding process is reducing distortion and wearing of the metalic alloys. A Fuzzy Expert System was developed for determining the wearing and durability properties of nitrided and non nitrided steels that were tested under different loads and different sliding speeds in the laboratory conditions.

In this study, mechanical properties of multiwalled carbon nanotubes / high density polyethylene ... more In this study, mechanical properties of multiwalled carbon nanotubes / high density polyethylene (MWCNT/HDPE) nanocomposite materials produced by method of injection molding have been investigated experimentally. Multi-walled carbon nanotubes (MWCNTs) have been incorporated into a high-density polyethylene (HDPE) matrix using twin screw extrusion and injection technique. High density polyethylene, which was reinforced with different percentages (1%, 3% and 5%) of carbon nanotubes, was produced in the form of tensile test bars and then tested. The tensile tests were performed according to ASTM D 638 test standards. The increase in tensile strength as a result of the added carbon nanotube was studied. After the experiments, changes of mechanism at fracture surfaces were examined. Experiments were repeated three times. As a result, it could be inferred that minimum percentage of carbon nanotubes reinforcement should be between 1% 3%.

Journal of Alloys and Compounds, 2019

The work presents the metal injection molding (MIM) of carbon nanotubes reinforced aluminium matr... more The work presents the metal injection molding (MIM) of carbon nanotubes reinforced aluminium matrix nanocomposite. The paraffin wax (PW), high density polyethylene (HDPE), stearic acid (SA) is used as a binder. Sintering of aluminium is a critical issue in injection molding. The new blind mold cavity sintering method is adopted to impart the strength in the MMC. The surface morphology is observed by the SEM. It is seen that aluminium particles uniformly welded and wide pores are visible in the MMC-Al product. Further the low temperature blind mold sintering helps to retain CNTs in the MMC-Al matrix. This imparts the higher hardness which is comparable with the aluminium alloy. The hardness tests carried out on sintered samples shows the results ranging from 42 to 73 BHN. The pores in these samples tested are in the ranges from 0.25µm to 1.0µm.

This paper proposes a Fuzzy Expert System design to determine the wearing properties of nitrided ... more This paper proposes a Fuzzy Expert System design to determine the wearing properties of nitrided and non nitrided steel. The proposed Fuzzy Expert System approach helps the user and the manufacturer to forecast the wearing properties of nitrided and non nitrided steel under specified laboratory conditions. Surfaces of the engineering components are often nitrided for improving wear, corosion, fatigue specifications. A major property of nitriding process is reducing distortion and wearing of the metalic alloys. A Fuzzy Expert System was developed for determining the wearing and durability properties of nitrided and non nitrided steels that were tested under different loads and different sliding speeds in the laboratory conditions.

Surface Review and Letters, 2017

Wear and friction hold an important place in engineering. Currently, scientific societies are str... more Wear and friction hold an important place in engineering. Currently, scientific societies are struggling to control wear by means of studies on lubricants. Boric acid constitutes an important alternative with its good tribological properties similar to MO2S and graphite alongside with low environmental impacts. Boric acid can be used as a solid lubricant itself whereas it can be added or blended into mineral oils in order to yield better mechanical and tribological properties such as low shear stress due to the lamellar structure and low friction, wear and surface roughness rates. In this study, distinguishing from the literature, boric acid addition effect considering the temperature was investigated for the conventional ranges of internal combustion engines. Surface roughness, wear and friction coefficient values were used in order to determine tribological properties of boric acid as an environmentally friendly additive and mineral oil mixture in the present study. Wear experimen...

International Journal of Applied Mathematics, Electronics and Computers, 2015

Utilization of shape memory alloys is rapidly spreading to many technological areas. From this po... more Utilization of shape memory alloys is rapidly spreading to many technological areas. From this point, alloys with shape memory are used in various fields such as temperature sensors in electronics, test valves in medicine, radiator fans in automotive and multi leg mobile robots. Application of nitinol fibers, which are actually shape memory alloys, as muscle fibers in industrial robots are increasing day by day. In this study, several tests were carried on aiming for the operational performance of nitinol fibers that are easy to control, economic, silent and harmless to environment and that have increasing utilization in recent motion technology. By using embedded systems, contraction (spasm) ratios and electrical current passing through the fibers were measured after 0.04 and 0.06 inch nitinol fibers were subjected to various voltages. Additionally, yielding limit value of nitinol fibers at split (breaking) point were detected. In the realized test system, ATmega 2560 microprocessor was took part as an embedded system in the Open Source Arduino Mega electronic card.

International Journal of Materials, Mechanics and Manufacturing, 2015

Tires are important parts of every vehicle including tractors and other off-road vehicles. Thus, ... more Tires are important parts of every vehicle including tractors and other off-road vehicles. Thus, structural and operational characteristics determination of the tires is too important. Tire deflection and tire contact area are functions of tractive performance. In this study an electronic system was designed in order to determine deflection of the tire. Deflection and contact area experiments were conducted by means of single wheel tester. As a result; the effects on deflection of dynamic axle load and inflation pressure were found significant (P<0.01) by utilizing variance analysis. There was a linear relationship between deflection and contact area of tire. The deflection of the tire increased with dynamic axle load for all inflation pressures tested. The deflection decreased with increasing inflation pressure. Additionally, increase in the tire load and decrease in the tire inflation pressure lead to bigger the tire contact area.

Journal of Image and Graphics, 2016

Today, image processing applications in agriculture seems to spread rapidly. Image processing in ... more Today, image processing applications in agriculture seems to spread rapidly. Image processing in agriculture are used in many areas such as classification of products, the detection of weeds, crop yields and weight estimation. In this study weight estimation of bread wheat and durum wheat in different amounts was performed by using image processing techniques. Image processing techniques were applied by using Matlab software. The counting of wheat kernels in image and weight estimation was carried out. Success rates were determined by comparing estimated weights of wheat kernels and their actual weight.

Bu çalışmanın amacı, karbon nano tüp (CNT) takviyeli plastik boruların deniz suyu içerisinde kull... more Bu çalışmanın amacı, karbon nano tüp (CNT) takviyeli plastik boruların deniz suyu içerisinde kullanılabilirliği ve bunun sonucunda mekanik özelliklerdeki değişimi incelemektir. Deneylerde kullanılan cam/epoksi borular, [±55]3 fiber oryantasyonuna sahip olup; filaman sarım metoduyla üretilmiştir. İkincil takviye malzemesi olarak ağırlıkça %1 oranında CNT kullanılmıştır. Deney numuneleri, kuru ortamın yanı sıra 2,3,4,6 ve 9 aylık reel sürelerle deniz suyu içerisinde bekletildikten sonra çekme ve sertlik testlerine tabi tutulmuşlardır. Testler, ASTM D 2290 standardına göre split disk metoduna uygun halka numuneler üzerinde gerçekleştirilmiştir. Sonuçlar, referans malzemesi cam takviyeli plastikten (CTP) elde edilen sonuçlar ile kıyaslama yapılmıştır. Elde edilen sonuçlara göre CNT'lerin kompozit yapı içerisine girmiş halde üretilmesinin delaminasyon hasarını azalttığı ve bunun sonucunda da kuru ortam şartlarında %21, uzun dönem kullanımlarda ise yaklaşık %18 mukavemet artışı sağladığı belirlenmiştir.

The aim of this study is to investigate the effect of the seawater on tensile behavior of the CNT... more The aim of this study is to investigate the effect of the seawater on tensile behavior of the CNT reinforced composite automotive materials. E-glass / epoxy tubes, produced by filament winding method, have [± 55]3 fiber orientation. As well as dry condition, specimens, immersed in seawater for 2, 3, 4, 6, and 9 month, were subjected to tensile test, using universal tensile testing machine. Tests were carried out with ring samples appropriate to split disk test standard (ASTM D2290). As well as tensile test, hardness testing was carried out on all samples waiting in the water. In the study, comparison will be conducted with reference material that is neat glass reinforced plastic (GRP) by using CNT reinforcement. In the study, comparison will be conducted with reference material that is glass reinforced plastic without nano material reinforcement (GRP) by using nano material reinforcement at predetermined percentages. Obtained conclusions were evaluated with various help of pictures ...

The common exercise in investigations and industrial applications for tires and specifically trac... more The common exercise in investigations and industrial applications for tires and specifically tractor tires is experimenting. However, there are difficulties which will be detailed in the text. Similar issues are encountered in fluid mechanics, but fluid mechanics studies sometimes involve scaled models and uses similarity approaches to overcome some of the difficulties. However only one significant study has been encountered in the literature about tire scaling and no study is encountered about tractor tires. In this report, scaling, similarity and dimensionless analyses are introduced first. Then the work about tire scaling is viewed. Points for scaling tractor tires are proposed. Some concluding remarks and propositions are made for future work.

Cekis test duzenekleri ceki performansi ve toprak sikismasi deneylerinde yogun olarak kullanilmak... more Cekis test duzenekleri ceki performansi ve toprak sikismasi deneylerinde yogun olarak kullanilmaktadir. Tarim traktorlerinde kullanilan lastiklerin ceki mekanigi uzerinde arastirmalar yapabilmesi icin cesitli cekis test duzenekleri tasarlanmis ve imal edilmistir. Bu test duzenekleri, cevresel lastik hizi, lastik patinaji ve dinamik aks yukunu kontrol edebilmektedir. Bu duzeneklerin gelistirilmesi ile farkli zeminlerde denemeler yapma yeteneginin yansira, gelismis olcum sistemleri kullanilarak daha hassas ve dogru veriler alma imkâni saglamistir. Bu duzeneklerde ilerleme hizini, lastik ic basincini, dinamik aks yukunu, patinaji ve net cekisi kontrol edebilmek icin geri bildirim saglayan bilgisayar sistemleri kullanilmaktadir. Bu calismada tarim traktor lastiklerinde kullanilan muharrik lastiklerin ceki performans deneylerinde kullanilmak icin tasarlanan ve gelistirilen deney duzenekleri aciklanmistir.

Статья посвящена анализу резолюции № 239, предложенной сенатором Ванденбергом и обеспечившей Соед... more Статья посвящена анализу резолюции № 239, предложенной сенатором Ванденбергом и обеспечившей Соединѐнным Штатам возможность участия в региональных организациях безопасности за пределами американских континентов вопреки "Прощальной речи" Джорджа Вашингтона и "доктрине Монро". В статье отмечается, что авторитет Артура Ванденберга, сенатора от Республиканской партии, во многом сыграл решающую роль в принятии решения Сенатом США. Делается вывод о том, что без резолюции Ванденберга у Гарри Трумэна и его администрации было бы значительно больше сложностей в вопросе ратификации Сенатом Договора о создании НАТО.

Many studies on tractive performance of tractor tires have been carried out to solve soil-wheel i... more Many studies on tractive performance of tractor tires have been carried out to solve soil-wheel interaction problems in the last decades. The purpose of this study is to experimentally determine effects on tractive performance of radial and bias-ply drive tires at three different tire lug heights, axle loads and inflation pressures. The experiments were carried out in stubble field conditions. To obtain sufficient performance data, a new single wheel tester was designed and manufactured. Travel reduction, net traction ratio and tractive efficiency varied from 3.3% to 34.1%, 0.24 to 0.93 and from 0.27 to 0.78 respectively depending on drawbar pull. The effects of tire type, lug height, dynamic axle load and inflation pressure on tractive efficiency were found significant (P<0.01) by the performed variance analysis and LSD tests. Radial tires provide better tractive performance compared with bias-ply tires. The tractive efficiency increased especially with increasing dynamic axle l...

Energy, 2015

In order to utilize energy in the most efficient way in off-road vehicles, soil–wheel interaction... more In order to utilize energy in the most efficient way in off-road vehicles, soil–wheel interaction should be investigated carefully since considerable amount of energy is lost due to tractive performance. In this study, the effects of radial tire on tractive performance at three different tire lug heights, axle loads and inflation pressures were experimentally determined. To obtain sufficient performance data, a new single wheel tester was designed and manufactured. Prior to experiments, properties of stubble field were determined. The tractive efficiency was found to increase with increasing dynamic axle load while decreasing with increasing tire inflation pressure. Dynamic axle load of the tire was the major contributory factor in the traction performance as compared with other independent variables. Seven different Artificial Neural Network and two types of Support Vector Regression models have been designed to predict the tractive efficiency. To evaluate the success of system, various statistical measures such as Mean Absolute Error, Root Mean Squared Error and Coefficient Determination have been used. The results show that the Artificial Neural Network model trained using Levenberg–Marquardt algorithm has produced more accurate results.

International Journal of Materials, Mechanics and Manufacturing, 2015

In this study, Multiwall Carbon Nanotubes (MWCNT) reinforced High Density Polyethylene (HDPE) mat... more In this study, Multiwall Carbon Nanotubes (MWCNT) reinforced High Density Polyethylene (HDPE) materials were used. Mechanical properties of the samples reinforced with Carbon Nanotubes at weight ratios of 1%, 3% and 5% were investigated. Reinforced samples were compared to samples produced with pure High density Polyethylene. Samples were produced by plastic injection method. The samples were then subjected to experiments and impact resistance values were measured in accordance with ASTM D6110 standards. Also Thermogravimetric Analyses (TGA) was performed for and Multi-Wall Carbon Nanotubes within the High Density Polyethylene. At the end of the study, it was observed that impact resistance decreased with increasing carbon nanotube reinforcement amount. Impact resistance of samples produced by means of plastic injection was decreased by 35% comparing with samples produced from pure HDPE. These results were explained with the fact that structures of composite materials were transformed to a tougher and fragile phase. In the TGA investigations, it was seen that mass loss breakdown temperature and melting point temperature increased by MCWNT ratio in the composite samples.

International Journal of Materials, Mechanics and Manufacturing, 2015

In this paper response surface methodology (RSM) was used to study the transesterification reacti... more In this paper response surface methodology (RSM) was used to study the transesterification reaction of safflower for biodiesel production. Biodiesel is alternative fuel, with catalyst and alcohols reaction production, from vegetable oils, animal oils and waste fried oils. But there are fuel problems to be solved before biodiesel. These are storage time, storage conditions and cloudy and flow points which have flow peculiarity in the low heats. In this research, physical and chemical properties as a fuel of Safflower Methyl Ester (SME) which are biodiesel fuels are determined. In this research, method of transesterification is employed. Attitudes in storage time and storage conditions of SME are investigated. As a result, SME viscosity figures, according to measured dates, are below 40 Redwood min. at 40°C. Also the effects of outer temperature and fuel temperature on viscosity were found significant (P<0.01) by the performed variance analysis.

DergiPark (Istanbul University), 2017

Many studies on tractive performance of tractor tires have been carried out to solve soil-wheel i... more Many studies on tractive performance of tractor tires have been carried out to solve soil-wheel interaction problems in the last decades. The purpose of this study is to experimentally determine effects on tractive performance of radial and bias-ply drive tires at three different tire lug heights, axle loads and inflation pressures. The experiments were carried out in stubble field conditions. To obtain sufficient performance data, a new single wheel tester was designed and manufactured. Travel reduction, net traction ratio and tractive efficiency varied from 3.3% to 34.1%, 0.24 to 0.93 and from 0.27 to 0.78 respectively depending on drawbar pull. The effects of tire type, lug height, dynamic axle load and inflation pressure on tractive efficiency were found significant (P<0.01) by the performed variance analysis and LSD tests. Radial tires provide better tractive performance compared with bias-ply tires. The tractive efficiency increased especially with increasing dynamic axle load and decreased with increasing tire inflation pressure. Tire dynamic axle load was the major contributory factor on tractive performance as compared with other independent variables. For a given drawbar pull, it was observed that tractive efficiency of radial tire can be maximized by selecting appropriate levels of lug height, dynamic axle load and inflation pressure.

determine the wearing properties of nitrided and non nitrided steel. The proposed Fuzzy Expert Sy... more determine the wearing properties of nitrided and non nitrided steel. The proposed Fuzzy Expert System approach helps the user and the manufacturer to forecast the wearing properties of nitrided and non nitrided steel under specified laboratory conditions. Surfaces of the engineering components are often nitrided for improving wear, corosion, fatigue specifications. A major property of nitriding process is reducing distortion and wearing of the metalic alloys. A Fuzzy Expert System was developed for determining the wearing and durability properties of nitrided and non nitrided steels that were tested under different loads and different sliding speeds in the laboratory conditions.

In this study, mechanical properties of multiwalled carbon nanotubes / high density polyethylene ... more In this study, mechanical properties of multiwalled carbon nanotubes / high density polyethylene (MWCNT/HDPE) nanocomposite materials produced by method of injection molding have been investigated experimentally. Multi-walled carbon nanotubes (MWCNTs) have been incorporated into a high-density polyethylene (HDPE) matrix using twin screw extrusion and injection technique. High density polyethylene, which was reinforced with different percentages (1%, 3% and 5%) of carbon nanotubes, was produced in the form of tensile test bars and then tested. The tensile tests were performed according to ASTM D 638 test standards. The increase in tensile strength as a result of the added carbon nanotube was studied. After the experiments, changes of mechanism at fracture surfaces were examined. Experiments were repeated three times. As a result, it could be inferred that minimum percentage of carbon nanotubes reinforcement should be between 1% 3%.

Journal of Alloys and Compounds, 2019

The work presents the metal injection molding (MIM) of carbon nanotubes reinforced aluminium matr... more The work presents the metal injection molding (MIM) of carbon nanotubes reinforced aluminium matrix nanocomposite. The paraffin wax (PW), high density polyethylene (HDPE), stearic acid (SA) is used as a binder. Sintering of aluminium is a critical issue in injection molding. The new blind mold cavity sintering method is adopted to impart the strength in the MMC. The surface morphology is observed by the SEM. It is seen that aluminium particles uniformly welded and wide pores are visible in the MMC-Al product. Further the low temperature blind mold sintering helps to retain CNTs in the MMC-Al matrix. This imparts the higher hardness which is comparable with the aluminium alloy. The hardness tests carried out on sintered samples shows the results ranging from 42 to 73 BHN. The pores in these samples tested are in the ranges from 0.25µm to 1.0µm.

This paper proposes a Fuzzy Expert System design to determine the wearing properties of nitrided ... more This paper proposes a Fuzzy Expert System design to determine the wearing properties of nitrided and non nitrided steel. The proposed Fuzzy Expert System approach helps the user and the manufacturer to forecast the wearing properties of nitrided and non nitrided steel under specified laboratory conditions. Surfaces of the engineering components are often nitrided for improving wear, corosion, fatigue specifications. A major property of nitriding process is reducing distortion and wearing of the metalic alloys. A Fuzzy Expert System was developed for determining the wearing and durability properties of nitrided and non nitrided steels that were tested under different loads and different sliding speeds in the laboratory conditions.

Surface Review and Letters, 2017

Wear and friction hold an important place in engineering. Currently, scientific societies are str... more Wear and friction hold an important place in engineering. Currently, scientific societies are struggling to control wear by means of studies on lubricants. Boric acid constitutes an important alternative with its good tribological properties similar to MO2S and graphite alongside with low environmental impacts. Boric acid can be used as a solid lubricant itself whereas it can be added or blended into mineral oils in order to yield better mechanical and tribological properties such as low shear stress due to the lamellar structure and low friction, wear and surface roughness rates. In this study, distinguishing from the literature, boric acid addition effect considering the temperature was investigated for the conventional ranges of internal combustion engines. Surface roughness, wear and friction coefficient values were used in order to determine tribological properties of boric acid as an environmentally friendly additive and mineral oil mixture in the present study. Wear experimen...

International Journal of Applied Mathematics, Electronics and Computers, 2015

Utilization of shape memory alloys is rapidly spreading to many technological areas. From this po... more Utilization of shape memory alloys is rapidly spreading to many technological areas. From this point, alloys with shape memory are used in various fields such as temperature sensors in electronics, test valves in medicine, radiator fans in automotive and multi leg mobile robots. Application of nitinol fibers, which are actually shape memory alloys, as muscle fibers in industrial robots are increasing day by day. In this study, several tests were carried on aiming for the operational performance of nitinol fibers that are easy to control, economic, silent and harmless to environment and that have increasing utilization in recent motion technology. By using embedded systems, contraction (spasm) ratios and electrical current passing through the fibers were measured after 0.04 and 0.06 inch nitinol fibers were subjected to various voltages. Additionally, yielding limit value of nitinol fibers at split (breaking) point were detected. In the realized test system, ATmega 2560 microprocessor was took part as an embedded system in the Open Source Arduino Mega electronic card.

International Journal of Materials, Mechanics and Manufacturing, 2015

Tires are important parts of every vehicle including tractors and other off-road vehicles. Thus, ... more Tires are important parts of every vehicle including tractors and other off-road vehicles. Thus, structural and operational characteristics determination of the tires is too important. Tire deflection and tire contact area are functions of tractive performance. In this study an electronic system was designed in order to determine deflection of the tire. Deflection and contact area experiments were conducted by means of single wheel tester. As a result; the effects on deflection of dynamic axle load and inflation pressure were found significant (P<0.01) by utilizing variance analysis. There was a linear relationship between deflection and contact area of tire. The deflection of the tire increased with dynamic axle load for all inflation pressures tested. The deflection decreased with increasing inflation pressure. Additionally, increase in the tire load and decrease in the tire inflation pressure lead to bigger the tire contact area.

Journal of Image and Graphics, 2016

Today, image processing applications in agriculture seems to spread rapidly. Image processing in ... more Today, image processing applications in agriculture seems to spread rapidly. Image processing in agriculture are used in many areas such as classification of products, the detection of weeds, crop yields and weight estimation. In this study weight estimation of bread wheat and durum wheat in different amounts was performed by using image processing techniques. Image processing techniques were applied by using Matlab software. The counting of wheat kernels in image and weight estimation was carried out. Success rates were determined by comparing estimated weights of wheat kernels and their actual weight.

Bu çalışmanın amacı, karbon nano tüp (CNT) takviyeli plastik boruların deniz suyu içerisinde kull... more Bu çalışmanın amacı, karbon nano tüp (CNT) takviyeli plastik boruların deniz suyu içerisinde kullanılabilirliği ve bunun sonucunda mekanik özelliklerdeki değişimi incelemektir. Deneylerde kullanılan cam/epoksi borular, [±55]3 fiber oryantasyonuna sahip olup; filaman sarım metoduyla üretilmiştir. İkincil takviye malzemesi olarak ağırlıkça %1 oranında CNT kullanılmıştır. Deney numuneleri, kuru ortamın yanı sıra 2,3,4,6 ve 9 aylık reel sürelerle deniz suyu içerisinde bekletildikten sonra çekme ve sertlik testlerine tabi tutulmuşlardır. Testler, ASTM D 2290 standardına göre split disk metoduna uygun halka numuneler üzerinde gerçekleştirilmiştir. Sonuçlar, referans malzemesi cam takviyeli plastikten (CTP) elde edilen sonuçlar ile kıyaslama yapılmıştır. Elde edilen sonuçlara göre CNT'lerin kompozit yapı içerisine girmiş halde üretilmesinin delaminasyon hasarını azalttığı ve bunun sonucunda da kuru ortam şartlarında %21, uzun dönem kullanımlarda ise yaklaşık %18 mukavemet artışı sağladığı belirlenmiştir.

The aim of this study is to investigate the effect of the seawater on tensile behavior of the CNT... more The aim of this study is to investigate the effect of the seawater on tensile behavior of the CNT reinforced composite automotive materials. E-glass / epoxy tubes, produced by filament winding method, have [± 55]3 fiber orientation. As well as dry condition, specimens, immersed in seawater for 2, 3, 4, 6, and 9 month, were subjected to tensile test, using universal tensile testing machine. Tests were carried out with ring samples appropriate to split disk test standard (ASTM D2290). As well as tensile test, hardness testing was carried out on all samples waiting in the water. In the study, comparison will be conducted with reference material that is neat glass reinforced plastic (GRP) by using CNT reinforcement. In the study, comparison will be conducted with reference material that is glass reinforced plastic without nano material reinforcement (GRP) by using nano material reinforcement at predetermined percentages. Obtained conclusions were evaluated with various help of pictures ...

The common exercise in investigations and industrial applications for tires and specifically trac... more The common exercise in investigations and industrial applications for tires and specifically tractor tires is experimenting. However, there are difficulties which will be detailed in the text. Similar issues are encountered in fluid mechanics, but fluid mechanics studies sometimes involve scaled models and uses similarity approaches to overcome some of the difficulties. However only one significant study has been encountered in the literature about tire scaling and no study is encountered about tractor tires. In this report, scaling, similarity and dimensionless analyses are introduced first. Then the work about tire scaling is viewed. Points for scaling tractor tires are proposed. Some concluding remarks and propositions are made for future work.

Cekis test duzenekleri ceki performansi ve toprak sikismasi deneylerinde yogun olarak kullanilmak... more Cekis test duzenekleri ceki performansi ve toprak sikismasi deneylerinde yogun olarak kullanilmaktadir. Tarim traktorlerinde kullanilan lastiklerin ceki mekanigi uzerinde arastirmalar yapabilmesi icin cesitli cekis test duzenekleri tasarlanmis ve imal edilmistir. Bu test duzenekleri, cevresel lastik hizi, lastik patinaji ve dinamik aks yukunu kontrol edebilmektedir. Bu duzeneklerin gelistirilmesi ile farkli zeminlerde denemeler yapma yeteneginin yansira, gelismis olcum sistemleri kullanilarak daha hassas ve dogru veriler alma imkâni saglamistir. Bu duzeneklerde ilerleme hizini, lastik ic basincini, dinamik aks yukunu, patinaji ve net cekisi kontrol edebilmek icin geri bildirim saglayan bilgisayar sistemleri kullanilmaktadir. Bu calismada tarim traktor lastiklerinde kullanilan muharrik lastiklerin ceki performans deneylerinde kullanilmak icin tasarlanan ve gelistirilen deney duzenekleri aciklanmistir.

Статья посвящена анализу резолюции № 239, предложенной сенатором Ванденбергом и обеспечившей Соед... more Статья посвящена анализу резолюции № 239, предложенной сенатором Ванденбергом и обеспечившей Соединѐнным Штатам возможность участия в региональных организациях безопасности за пределами американских континентов вопреки "Прощальной речи" Джорджа Вашингтона и "доктрине Монро". В статье отмечается, что авторитет Артура Ванденберга, сенатора от Республиканской партии, во многом сыграл решающую роль в принятии решения Сенатом США. Делается вывод о том, что без резолюции Ванденберга у Гарри Трумэна и его администрации было бы значительно больше сложностей в вопросе ратификации Сенатом Договора о создании НАТО.

Many studies on tractive performance of tractor tires have been carried out to solve soil-wheel i... more Many studies on tractive performance of tractor tires have been carried out to solve soil-wheel interaction problems in the last decades. The purpose of this study is to experimentally determine effects on tractive performance of radial and bias-ply drive tires at three different tire lug heights, axle loads and inflation pressures. The experiments were carried out in stubble field conditions. To obtain sufficient performance data, a new single wheel tester was designed and manufactured. Travel reduction, net traction ratio and tractive efficiency varied from 3.3% to 34.1%, 0.24 to 0.93 and from 0.27 to 0.78 respectively depending on drawbar pull. The effects of tire type, lug height, dynamic axle load and inflation pressure on tractive efficiency were found significant (P<0.01) by the performed variance analysis and LSD tests. Radial tires provide better tractive performance compared with bias-ply tires. The tractive efficiency increased especially with increasing dynamic axle l...

Energy, 2015

In order to utilize energy in the most efficient way in off-road vehicles, soil–wheel interaction... more In order to utilize energy in the most efficient way in off-road vehicles, soil–wheel interaction should be investigated carefully since considerable amount of energy is lost due to tractive performance. In this study, the effects of radial tire on tractive performance at three different tire lug heights, axle loads and inflation pressures were experimentally determined. To obtain sufficient performance data, a new single wheel tester was designed and manufactured. Prior to experiments, properties of stubble field were determined. The tractive efficiency was found to increase with increasing dynamic axle load while decreasing with increasing tire inflation pressure. Dynamic axle load of the tire was the major contributory factor in the traction performance as compared with other independent variables. Seven different Artificial Neural Network and two types of Support Vector Regression models have been designed to predict the tractive efficiency. To evaluate the success of system, various statistical measures such as Mean Absolute Error, Root Mean Squared Error and Coefficient Determination have been used. The results show that the Artificial Neural Network model trained using Levenberg–Marquardt algorithm has produced more accurate results.

International Journal of Materials, Mechanics and Manufacturing, 2015

In this study, Multiwall Carbon Nanotubes (MWCNT) reinforced High Density Polyethylene (HDPE) mat... more In this study, Multiwall Carbon Nanotubes (MWCNT) reinforced High Density Polyethylene (HDPE) materials were used. Mechanical properties of the samples reinforced with Carbon Nanotubes at weight ratios of 1%, 3% and 5% were investigated. Reinforced samples were compared to samples produced with pure High density Polyethylene. Samples were produced by plastic injection method. The samples were then subjected to experiments and impact resistance values were measured in accordance with ASTM D6110 standards. Also Thermogravimetric Analyses (TGA) was performed for and Multi-Wall Carbon Nanotubes within the High Density Polyethylene. At the end of the study, it was observed that impact resistance decreased with increasing carbon nanotube reinforcement amount. Impact resistance of samples produced by means of plastic injection was decreased by 35% comparing with samples produced from pure HDPE. These results were explained with the fact that structures of composite materials were transformed to a tougher and fragile phase. In the TGA investigations, it was seen that mass loss breakdown temperature and melting point temperature increased by MCWNT ratio in the composite samples.

International Journal of Materials, Mechanics and Manufacturing, 2015

In this paper response surface methodology (RSM) was used to study the transesterification reacti... more In this paper response surface methodology (RSM) was used to study the transesterification reaction of safflower for biodiesel production. Biodiesel is alternative fuel, with catalyst and alcohols reaction production, from vegetable oils, animal oils and waste fried oils. But there are fuel problems to be solved before biodiesel. These are storage time, storage conditions and cloudy and flow points which have flow peculiarity in the low heats. In this research, physical and chemical properties as a fuel of Safflower Methyl Ester (SME) which are biodiesel fuels are determined. In this research, method of transesterification is employed. Attitudes in storage time and storage conditions of SME are investigated. As a result, SME viscosity figures, according to measured dates, are below 40 Redwood min. at 40°C. Also the effects of outer temperature and fuel temperature on viscosity were found significant (P<0.01) by the performed variance analysis.