Yazar "Eker, Bülent" seçeneğine göre listele

Listeleniyor 1 - 18 / 18
  • Küçük Resim
    Öğe
    Carbon nanotube-based nanocomposites and their applications
    (Taylor & Francis Ltd, 2017) Ateş, Murat; Eker, Ayşegül Akdogan; Eker, Bülent
    The purpose of the current review article is to present a compherensive understanding regarding pros and cons of carbon nanotube-related nanocomposites and to find ways in order to improve the performance of nanocomposites with new designs. Nanomaterials including carbon nanotubes (CNTs) are employed in industrial applications such as supercapacitors, and biosensors, and etc. The present article has been prepared in three main categories. In the first part, carbon nanotube types have been presented, as single-walled carbon nanotubes, multi-walled carbon nanotubes, and also equivalent circuit models, which have been used to more clarify the experimental measurements of impedance. In the second part, nanocomposites with many carbon, inorganic and polymeric materials such as polymer/CNT, activated carbon/CNT, metal oxide/CNT, and carbon fiber/CNT have been investigated in more detail. In the third part, the focus in on the industrial applications of CNTs. including supercapacitors, biosensors, radar absorbing materials, solar cells, and corrosion protection studies. This review article explains the latest advances in carbon nanotubes and their applications in electrochemical, electrical and optical properties of nanocomposites.
  • Küçük Resim
    Öğe
    Design of a wind turbine working with the continuity principal
    (Multi Science Publ Co Ltd, 2006) Vardar, Ali; Eker, Bülent
    In the study, the purpose is to take advantage of low wind potentials and obtain high power values with small rotor diameters. Wind speed is considered to be increased with the help of continuity principle. With this aim, two different wind tunnel inlet diameters were used, being 5 m and 10 m, while the outled diameters of wind tunnels were chosen as 0,5 - 1 - 2 - 3 - 4 m. The most striking result obtained in this study was the formation of a power of 492352 kW at the outlet of wind tunnel when the inlet diameter of wind tunnel was 10 m, outlet diameter was 0,5 m and the inlet wind speed was 4 m/s. Under these conditions, the wind speed at the wind tunnel outlet reaches 1600 m/s. A new viewpoint to wind energy technology will be presented if the results obtained in this study are also obtained in empirical studies.
  • Küçük Resim
    Öğe
  • Küçük Resim
    Öğe
    Developing Packaging By Using Smart Material Which Helps to Realize Spoilage in Yoghurt
    (Trans Tech Publications Ltd, 2011) Eker, Bülent; Eker, Ayşegül Akdogan
    The important effect of yoghurt on people's health caused increasing of many technological works and researches not only in our country but also all over the world. The environment in which yoghurt kept, may cause many sort of germs and contamination paths by the effects of some factors which are fairly similar to its own structure. These factors change the shelf-life of yoghurt and finally cause spoilage in yoghurt. In this context, it is known that the scientific works in this area which are aiming to minimize this spoilage effect, focus on the yogurt structure and packaging of yoghurt. The aim of this paper is to improve a smart polymer material which interacts with serum and changes color of the package by considering serum occurring within the shelf-life of yoghurt. PP based material will be used with the biological agencies like kaoline and talc and implemented mainly or superficial, the color change will be arised if the serum's PH increases. In practice, everyone can see the color changes with the window which will be placed on the label and the window will include the cautions according to the color levels.
  • Küçük Resim
    Öğe
    Developing Wind-Concentrator Systems for the Use of Wind Turbines in Areas with Low Wind-Speed Potentials
    (Wiley-V C H Verlag Gmbh, 2015) Vardar, Ali; Eker, Bülent; Kurtulmuş, Ferhat; Taşkın, Onur
    The ability to supply energy in rural areas and in agricultural plants with renewable energy technologies, especially wind energy, is advantageous in terms of a sustainable environment and the increasing cost of energy. Today, wind turbines are used actively in many areas, some of which are for commercial purposes. Small-scale wind turbines that produce electricity directly have the necessary characteristics for use in agricultural plants. In this study, wind-concentrator systems for small-scale wind turbines that can be used in agricultural electrification applications have been designed for geographical areas where the wind-speed potential is low. Three different concentrator systems have been designed to make use of low wind-speed potentials and obtain high power values with relatively small rotor diameters. The three different designs have been produced as prototypes, and power values of 324-503 Wm(-2) (at 5 ms(-1) wind speed) can be obtained by concentrating the wind. The efficiency, power, energy production capacity, and economic elements of the models were determined, and the possible results for agricultural plants have been assessed. According to these assessments, the efficiency values are 71 and 90% for wind speed and 410 and 600% for wind power. The energy production capacities are a maximum of 6462, 5193, and 8226 kWhm(-2) per year for the conical wind-concentrator system, the wind-concentrator system with a panel, and the wind-concentrator system without a panel, respectively. If the energy production cost per unit of these systems is considered, these systems are not economical. Therefore, these systems must be produced on a large scale to become economical, and their size must be enlarged to reduce the cost. Consequently, the potential power values per unit area and the potential energy values per unit produced by the wind-concentrator systems will contribute to the production of more energy than that achieved by current wind turbines.
  • Küçük Resim
    Öğe
    Elasticity of a farm trailer's chassis at different twisting angles
    (Professional Engineering Publishing Ltd, 2008) Akdemir, Bahattin; Ülger, Poyraz; Eker, Bülent; Sağlam, Cihangir; Çelen, İlker Hüseyin; Aktaş, Türkan; Avcı, G.
    It is important to know the behaviours of materials used to design and manufacture farm trailers in the same way as is necessary for all mechanical systems. Fatigue tests for trailers give an idea about the behaviours of its components. Simulators are very useful test systems for applying fatigue tests under laboratory conditions. The aim of this research was to determine the effects of different twisting angles of a trailer chassis on a farm trailer by using a Simulator apparatus. Tests were carried Out in either static or dynamic conditions. The minimum and maximum twisting angles were selected as -10 degrees and +10 degrees for all tests respectively. The farm trailer was twisted for each 2 degrees and the system was stopped to measure the forces for static conditions. Measured forces were used to calculate the twisting moments. The experimental apparatus ran continuously between -10 degrees and +10 degrees and the forces were measured for each 2 degrees under dynamic conditions. The tests were performed at 26 cycles/min for twisting angles of +/- 10 degrees. The energy absorbed through hysteresis by the trailer chassis was calculated as 27 980 Nm. The total energy and the coefficient of absorption ability of the chassis were calculated as 107 849 Nm and 25.9 per cent respectively. The materials of the trailer chassis Must be more elastic than this value according to the literature to absorb vibrations created by the road or field. When the twisting moment of the trailer is smaller, it is possible that the trailer may fall over when going round a bend in the road. Stability requires high twisting moments. The absorption of vibration, however, requires smaller twisting moments.
  • Küçük Resim Yok
    Öğe
    FIRE EMERGENCY MANAGEMENT
    (Faculty of Engineering, University of Kragujevac, 2019) Eker, Bülent; Kargözler, Yalçin
    Emergency situations cause loss of life and financial losses in enterprises every year. However, this can be prevented. If businesses are prepared for such situations, damage and injury or loss of life can be prevented, their impact can be reduced, and businesses can return to their normal lives more quickly.Whether operating in a multistorey building or in an industrial complex; be the owner or tenant of your current property; Emergency management can be applied regardless of the size and size of the enterprise.You do not need vast emergency management information for start-up. What you need is your organization's senior management to authorize and implement a plan for emergency management and to support and adopt it as a business culture. In this paper, emergency management will be explained by examples. © 2019, Faculty of Engineering, University of Kragujevac. All rights reserved.
  • Küçük Resim
    Öğe
    Mechanical properties of plastic matrix composite materials used in tractor bonnets
    (Sage Publications Ltd, 2010) Becenen, Nilgün; Eker, Bülent; Şahin, Mumin
    The effects of chemical structure of the resin, reinforcement types, material thickness, and post-cure treatment on the mechanical properties of composite material were examined in this study. Composite materials were produced by combining chopped, woven, and felt glass fibers with thermoset plastic-based matrixes. Orthophtalic polyester (polives 701) and bisphenol-A epoxy vinyl ester (polives3401) resins were chopped in combination with a catalyst system composed of MEK-PEROKSIT and cobalt, and were reinforced with chopped, woven, and felt glass fiber. Composite materials were prepared using a hand lay-up method. Half of the prepared composite materials were post-cured, the other half remained non-treated. A total of 75 tests were performed. Tensile, bending, impact, and hardness tests were performed to determine the mechanical properties of the samples. The test results indicated that durable and strong tractor bonnets can be produced using vinyl ester-based matrix material and 90 degrees glass fiber woven reinforcement material, producing two-layered composite material and curing at 50 degrees C, 80 degrees C, and 110 degrees C.
  • Küçük Resim
    Öğe
    Microstructure and Oxidation Behavior of Atmospheric Plasma-Sprayed Thermal Barrier Coatings
    (Elsevier Inc., 2018) Avcı, A.; Eker, A.A.; Eker, Bülent
    Thermal barrier coatings (TBCs) are widely used as insulation layered at elevated temperatures in gas turbine components. Yttria-stabilized zirconia (YSZ) ceramic has outstanding properties such as phase stability at high temperature, a prolonged service lifetime, and low thermal conductivity, which make it a promising candidate. The high temperature of gas turbines leads to the transfer of oxygen from the top coat to the bond coat; therefore, oxidation occurs on the bond coat; it is called the thermally grown oxide layer and is mainly considered a failure mechanism of TBC systems. Gas turbine engines that have applications in energy production, transportation, and the defense industry depend on high-temperature TBCs for higher efficiency. During thermal cycling, mechanical forces can occur in turbine engines, oxidation, hot corrosion, the sintering of the top coat, and a thermal expansion coefficient mismatch between the metallic substrate and the ceramic top coat as a result of spallation or crack degradation. TBCs can be affected by coating materials, manufacturing processes, and their microstructure. Spallation of the ceramic top coat is a main problem for TBCs because it leads to oxidation, corrosion, and creeps in the TBC system. This chapter gives brief information about thermal barrier materials and the microstructure and oxidation behavior of TBCs. © 2018 Elsevier Inc. All rights reserved.
  • Küçük Resim Yok
    Öğe
    Modeling studies on the relation between wind speed and height: Tekirdag sample
    (Sila Science, 2011) Vardar, Ali; Eker, Bülent; Durgut, M. Recai; Okur, Ersen; Kurtulmuş, Ferhat
    The experiments of this study were conducted in Degirmenalti Campus of Namik Kemal University in Tekirdag, a province in northwestern Turkey between 2005-2008. An anemograph system which can measure wind speed and wind direction at 2 m and 10 m heights was used in this study. The recorded data was transferred to computer environment with a data logger. The relation between wind speed and height was modeled with the gathered data and it was compared with logarithmic wind speed. Also, artificial neural networks (ANN) method was used in wind speed estimation and error comparisons of the results of measurements and ANN estimations was done. The best results of the error analysis were gained from the developed mathematical model. Especially, the error rate of developed mathematical model for the wind speed values over 2 ms-1 remained under 5%. While error rates appeared to be higher in logarithmic wind speed model, they were quite near to the developed mathematical model in ANN method.
  • Küçük Resim
    Öğe
    Polyurethane foam materials and their industrial applications
    (Wiley, 2022) Ateş, Murat; Karadağ, Selin; Eker, Ayşegül Akdoğan; Eker, Bülent
    In this review article, polyurethane (PU) foam materials are presented in various industrial applications. PU foams have started to replace metals and plastics in various engineering applications by combining the hardness and durability of metal with the flexibility of rubber. PU foams can be synthesized with various isocyanates, polyols, chain extenders and crosslinkers to serve many specific applications, such as bio-based composite foam, flexible hard/soft PU foam, polymer foam etc. There are different factors to change of hard and soft segments of PUs. These changes form different products, such as urethane, biurets, allophanates and isocyamurates, etc. This review article mostly concentrates on the basic chemistry of the building blocks of PUs and recent developments in industrial applications of PU foams, such as insulator material, sound insulators, refrigerator and freezing insulators, furniture, shoes, automotive materials, coatings and adhesives and other applications. (c) 2022 Society of Industrial Chemistry.
  • Küçük Resim Yok
    Öğe
    Quality in Metallized Coating Applications
    (Univ Montenengro, Center Quality, 2010) Eker, Bülent
    Metalized coating is attained by atomizing the coating metal by melting with proper gas (propane, acetylene or others) and oxygen compound and then spraying it with compressed air all over the surface to be coated. Metallization in the application is the process of vaporization of the needed metal with tungsten in vacuumed media. This system among the PVD Coating groups is known as Evaporation Coating all through the world. Although the very fine metal layer that condenses over the product to be coated varies from sector to sector; it is generally used with aesthetic and decorative aims. The surface of the part to be coated is cleaned off the effects such as dirt, dust and oils etc. this cleaning method varies according to the size, shape and material of the piece to be coated. Surface cleaning before coating is very important in the sense of coating life, quality and strength. Otherwise, expected yield cannot be attained from the metalized and corrosion start can be observed shortly due to remnants on the places which are not thoroughly cleaned. Since metallization is a vaporization method; it is ionized by melting on all places which are in high-vacuumed. But there occurs an adsorption problem on some plastic types, therefore a smooth coating is attained applying an adherence through interlayer on these products before coating or with corona application. In food packaging sector metalized coated products are used because of their barrier feature towards light, water vapor, oxygen and other gases. This method of packaging is widely used in such kinds of sectors due to being most economical in packaging sector. For example; food packaging sector which holds a great place in flexible packaging group uses metalized coating system due to their barrier feature of metalized film with the aim of preventing oxidation of food products, decreasing the need of protective addition agent and extending the shell-life. Moreover cosmetic packaging group and many other sectors uses metalized coating due to its aesthetic feature with the aim of its being supportive to product promotion and reveal the decorative feature of the product. Metalized coating firms generally have quality and coating problems. In metalized coating processes done in series; expected amount and quality can not be attained generally. Therefore in this paper; how the quality is attained in metalized coating applications and the effective factors for this application will be explained.
  • Küçük Resim
    Öğe
    Search for Quality in Biosystem Engineering
    (Univ Montenengro, Center Quality, 2012) Eker, Bülent
    Today, engineering has become a disciplined field. The demand in food products caused the agricultural engineers to consider the matter in a different way. This consideration led the engineer to resolve the biological issues together with electronic and information disciplines and also advanced control, advanced technological materials and developed sensor systems. The subject has persuaded them to design solutions for problems related with living things and their environment. Bio-system engineering which has been developed for this purpose has become the application of technical knowledge aiming to fulfill the human requirements. The pursuit of bio-system engineering discipline are automation, new developed technologies, information technologies and human interaction, sensitive agriculture techniques, power and work machines, product technologies after harvest, structures and relation with environment, animal production technology, soil and water sources, rural development and planning. Bio-system engineering which covers such a wide area should reach the solution by using its system engineering feature first and then determine the process parameters of the subjects that it resolves. Therefore it has to attribute the reason - result relation in every stage to quality parameters. Therefore, in this announcement, the quality issues necessary for explaining the subjects dealt in bio-system engineering basis are examined one by one and solution models are created depending on these issues.
  • Küçük Resim Yok
    Öğe
    Spray Characterization of an Unmanned Aerial Vehicle for Agricultural Spraying
    (College of Agriculture and Food Science, University of the Philippines Los Banos, 2023) Önler, Eray; Özyurt, Hasan Berk; Şener, Mehmet; Arat, Sezen; Eker, Bülent; Çelen, İlker Hüseyin
    Sustainability and higher efficiency in crop production are possible with the use of new technologies. The use of unmanned aerial vehicles brings many advantages both in terms of monitoring agricultural areas and pesticide applications. This technology allows us to detect diseases and damages in an early manner and apply them in areas that are not accessible by conventional sprayers. However, a lack of knowledge on how to use UAVs and what parameters need to be considered prevent the widespread use of drone technology in agriculture. This study established parameters for spraying with clean water using a DJI Agras 14 MG-1P (RTK) Unmanned Aerial Vehicle. Droplet distribution and droplet analyses were examined in the studies carried out at different heights (1.5, 2.0, and 2.5 m) and flow rates (10, 15, 20, 25, and 30 L/ha). Droplets were analysed using DepositScan. Coefficients of variation of droplet distribution tend to decrease with the increasing spray rate. The trials with the closest values to uniformity are spraying applications made with a flight height of 2 m. When we evaluate pesticide efficacy according to the number of droplets per unit area, insecticides and all herbicides can be effective at applications with flight heights of 1.5 and 2 m and spray rate of 20 L/ha. While all spraying is done with flight heights of 1.5 and 2 m and spray rates of 25 L/ha, fungicides are ineffective when applied from 2.5 m height. As a result, this study found the measurements made at 2 m altitude and 20 L/ha spray rate have the highest coverage rate and lowest drift potential. © 2023, College of Agriculture and Food Science, University of the Philippines Los Banos. All rights reserved.
  • Küçük Resim
    Öğe
    Tarımsal Sulamada Kullanılan Santrifüj Pompa Çarkında Olabilecek Aşınmanın Belirlenmesi
    (Namık Kemal Üniversitesi, Ziraat Fakültesi, 2009) Türkboyları, Elif; Eker, Bülent
    Bu çalışmada, günde ortalama 6,5-7 saat çalıştırılan bir yatay milli santrifüj pompanın işletme karakteristikleri çıkarılmıştır. Yatay milli santrifüj pompanın (sulama uygulamalarında kullanılabilecek özellikte) bir depoya bağlanmasıyla oluşturulan kapalı devre (kendi içinde devir daim yapan) pompa sistemi 180 saat boyunca laboratuar koşullarında çalıştırılmış ve pompanın işletme özelliklerini tanımlamak için işletme karakteristikleri ölçülmüştür. Pompa işletme karakteristiklerinin ölçülmesinde ISO 2548 esas alınmıştır. Ayrıca pompanın işletme karakteristikleri ile çarkta meydana gelen aşınma ve korozyon arasında bağlantı kurulmaya çalışılmıştır.
  • Küçük Resim
    Öğe
    Tarımsal Sulamada Kullanılan Santrifüj Pompaların Alüminyum Çarklarında Meydana Gelebilecek Aşınmanın Belirlenmesi
    (Namık Kemal Üniversitesi, Ziraat Fakültesi, 2010) Yüksel, Elif; Eker, Bülent
    Bu çalışmada, günde ortalama 7-8 ve toplamda 180 saat olacak şekilde çalıştırılan bir monoblok santrifüj pompanın (alüminyum çarka sahip) çalıştırma dönemi sonunda çarkta meydana gelen aşınma ve korozyon saptanmaya çalışılmıştır. Monoblok santrifüj pompanın (sulama uygulamalarında kullanılabilecek özellikte) bir depoya bağlanmasıyla oluşturulan kapalı devre (kendi içinde devir daim yapan) pompa sistemi laboratuar koşullarında 180 saat boyunca çalıştırılmış ve sisteme ait eğriler çıkarılmıştır. Pompa işletme karakteristiklerinin ölçülmesinde TS EN ISO 9906/AC esas alınmıştır.
  • Küçük Resim
    Öğe
    Tarımsal Sulamada Kullanılan Santrifüj Pompaların Paslanmaz Çelik Malzemeden Yapılmış Çarklarında Meydana Gelebilecek Aşınmanın Belirlenmesi
    (Namık Kemal Üniversitesi, Ziraat Fakültesi, 2009) Yüksel, Elif; Eker, Bülent
    Bu çalışmada, günde ortalama 7 saat çalıştırılan bir yatay milli santrifüj pompanın (paslanmaz çelik çarka sahip) işletme karakteristikleri çıkarılmıştır. Yatay milli santrifüj pompanın (sulama uygulamalarında kullanılabilecek özellikte) bir depoya bağlanmasıyla oluşturulan kapalı devre (kendi içinde devir daim yapan) pompa sistemi laboratuar koşullarında 150 saat boyunca çalıştırılmış ve pompanın işletme özelliklerini tanımlamak için işletme karakteristikleri ölçülmüştür. Pompa işletme karakteristiklerinin ölçülmesinde ISO 2548 esas alınmıştır. Ayrıca pompanın işletme karakteristikleri ile çarkta meydana gelen aşınma esas alınarak aşınma-korozyon arasında bağlantı kurulmaya çalışılmıştır.
  • Küçük Resim Yok
    Öğe
    THE EFFECT OF DIGITAL TRANSFORMATION ON THE DEVELOPMENT OF QUALITY IN WORK LIFE
    (Faculty of Engineering, University of Kragujevac, 2019) Eker, Bülent
    Digital transformation has undergone our lives for the last 15 years. Now the internet has become one of the places where people spend most of their time. While change and transformation were very fast, it was easier for people to keep up with this change. With our digital transformation, our ideas, habits, ways of working, our business life have changed completely.Nowadays, the inevitable consequences of the effects of digital transformation on business models and customer behavior deeply affect the business world. This transformation in the business world, which gained momentum with the ease of access to information, also increased competition. Countries need a sufficient number of skilled workforce to capture and sustain digital transformation. In this paper, the effect of digital transformation on the development of quality in business life was examined on the basis of Accenture Digitization Index. © 2019, Faculty of Engineering, University of Kragujevac. All rights reserved.