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Tatlı sorgum bitkisi ve özsuyu alındıktan sonra geriye kalan posası birinci nesil biyoetanol, hayvan yemi, gübre, biyoyakıt ve selülozik biyoetanol üretimi gibi çeşitli amaçlar için değerlendirilmektedir ve geniş kullanım alanlarından dolayı gün geçtikçe önem kazanmaktadır. Bu çalışmada, farklı tatlı sorgum genotiplerinin özsuyu alındıktan sonra geriye kalan saplarında (posasında) teorik selülozik biyoetanol potansiyelinin belirlenmesi amaçlanmıştır. Bu amaçla yurt içi ve yurt dışındaki değişik kaynaklardan temin edilen 21 farklı tatlı sorgum (Sorghum bicolor var. saccharatum (L.) Mohlenbr.) genotipi materyal olarak kullanılmıştır. Tarla denemeleri, Çukurova (Adana) ikinci ürün koşullarında 2016 ve 2017 yıllarında yürütülmüştür. Bitkilerin hasadı, salkımdaki tanelerin süt-hamur olum dönemine denk gelen tarihlerde yapılmıştır. Hasat edilen bitkilerin yaprakları ve salkımları ayrıldıktan sonra saplar ekstrakte edilip özsuyu alınmıştır. Özsuyu alınan saplar (posalar) kurutulduktan sonra selüloz ve hemiselüloz analizleri yapılmış ve teorik selülozik biyoetanol verimleri kuru madde bazında L ton-1 ve L da-1 cinsinden hesaplanmıştır. Çalışma sonucunda iki yıllık ortalamalara göre; tatlı sorgum genotiplerinin selüloz içeriğinin %33.21-45.13, hemiselüloz içeriğinin %20.63-25.36, teorik selülozik biyoetanol veriminin ise 183.7-231.0 L ton-1 kuru madde (KM) ve 297.4-767.6 L da-1 (KM) arasında değiştiği saptanmıştır. Araştırmada özsuyu alındıktan sonra kalan posanın selülozik biyoetanol üretimi amacıyla kullanılabileceği ve Grass1, Tracy, UNL-Hyb-3 ve No91 genotiplerinin birim alanda 600 L da-1 üzerinde selülozik biyoetanol üretme kapasitesi ile öne çıkan genotipler oldukları görülmektedir. Tatlı sorgum bitkisinin özsuyundan biyoetanol elde edilmesi ve ayrıca geriye kalan küspesinden de selülozik biyoetanol üretilmesi ile yüksek biyokütle potansiyeline sahip bitkinin tamamından yararlanılarak daha fazla biyoetanol elde edilebileceği ve böylece yenilenebilir enerji kaynağı olarak sürdürülebilirlik, çevre ve ekonomi gibi çeşitli açılardan avantajlar sağlanabileceği sonucuna ulaşılmaktadır.

This study was performed to determine the effects of the densification process and glue type in wood material on dowel tensile performance. For this purpose, 8 mm and 10 mm diameter dowels were obtained from black poplar (Populus nigra) and Eastern spruce (Picea orientalis L.), which were densified at 50% and 75% ratios. The dowels were bonded with PVAc and D-VTKA glue separately after drilling 18 mm deep holes in the edge of the melamine-coated particleboard. The tensile performance test was determined with the Universal test device according to TS 2475 and ASTM-D 1035 principles. As a result, Eastern spruce wood had the highest tensile performance (kg/cm2), and poplar wood had the lowest (173.66). For the dowel diameter parameter, the highest value (195.11) was found at 8 mm in diameter and the lowest value (161.05) was found at 10 mm in diameter. In terms of glue type, the highest value (185.92) was seen at PVAc while the lowest value (170.24) was seen at D-VTKA. And for the densification ratios, the highest value (191.4) was determined at 75%, while the lowest value was found in control samples at (167.4). According to the wood species, densification ratio, dowel diameter and glue type interaction, the highest value was determined at Es + d75% + 10mm + PVAc as (303.5) and the lowest value was found at P + d50% + 10mm + Dv as (110). As a result, where the dowel's high tensile performance is sought, using a 10 mm diameter dowel made from 75% densified spruce wood with PVAc glue may be advantageous.

In this study, the fuel characteristics of biodiesel produced from jojoba [Simmondsia chinensis (Link) Schneider] oil and biodiesel obtained from the jojoba oil procured under laboratory conditions were compared. For this purpose, jojoba seed endosperm and oil, which was attained from the jojoba endosperm calli via soxhlet extraction, was obtained. Biodiesel was produced from this oil via the transesterification method. It was determined that the fuel characteristics of the biodiesels produced from the oil procured under the laboratory conditions and the oil attained from the seeds were close to each other, and it was observed that the other features were in parallel with the standards, except for the viscosity and freeze point. This research study offers a solution for the raw material problem, which is one of the most important obstacles against the widespread use of biodiesel, in terms of environmental and economic aspects.

With the improvement of lithium-ion battery (LIB) technology, safety is becoming increasingly urgent topic for battery electric vehicles (BEVs). Short circuits, overcharging, high temperatures and overheating can cause thermal runaway reactions and the release of the flammable electrolyte which makes fire suppression very difficult. This study focuses on the mechanism of thermal runaway and fire suppression applications of LIBs. In order to understand this, 10 experiments were carried out. The experiments were divided into as Exp. A and Exp. B. A manual water suppression system was used in Exp. A and an automatic boron-based suppression system (AUT-BOR) was used in Exp. B. LIBs were heated in a controlled manner with a heat source and the effects of thermal runaway and fire suppression were observed. In Exp. A, a large amount of water was required to extinguish the LIB fires. The holes and slits which formed in the LIB after a fire were useful for injecting water. A projectile effect of cylindrical cells was observed in Exp. A. The Exp. B results showed that AUT-BOR mitigates risks effectively and safely. Also, AUT-BOR provides an early fire warning system and spot cooling to prevent thermal runaway reactions while localizing and suppressing the fire. In Exp. B, fire detection and suppression occurred without any explosion.

Purpose The endurance of small unmanned air vehicles (UAVs) is directly associated with the energy density of the propulsion system used. As the batteries commonly used in small UAVs have a relatively low energy density, they are not sufficient for long-term endurance tasks. The purpose of this paper is to offer a solution to increase the endurance of a concept small UAV with combination of different power sources. The design, construction and ground tests of fuel cell-powered hybrid propulsion systems are presented in this paper. Design/methodology/approach The power requirements of a concept UAV were calculated according to aerodynamic calculations and then, hybrid propulsion system sources are determined. The hybrid system consists of a 100 W scale proton-exchange membrane (PEM) type fuel cell stack, lithium-polymer battery, solar cells and power management system (PMS). Subsequently, this hybrid power system was integrated with the new design of PMS and then series of ground tests were carried out. Findings This experimental study proved that it is theoretically possible to obtain an endurance of around 3 h for concept UAV with the proposed hybrid system. Practical implications The research study shows that fuel cell-based hybrid propulsion system with the proposed PMS can be widely used to obtain extended endurance in small UAVs. Originality/value A hybrid propulsion system with a novel PMS unit is proposed for small UAVs and the ground tests were implemented.

COVİD-19 salgını ilk olarak 31 Aralık 2019 tarihinde Çin hükümetinin Dünya Sağlık Örgütüne bildirmesiyle kamuoyunun gündemine geldi, Küresel olarak 3,4 milyondan fazla teyit edilmiş vaka ve 86 binden fazla ölüm vakasına neden oldu (5 Mayıs 2020 itibariyle). Covid-19 dünya ekonomisini etkilediğinden dolayı küresel bir konu haline gelmiştir. Bu çalışma mevcut raporları kullanarak salgının Dünya ekonomisine ve Türkiye’nin tedarik zincirine etkisini analiz eden bir inceleme makalesidir. Sonuç olarak Salgının diğer ülke ekonomileri gibi Türkiye ekonomisini de kötü yönde etkileyeceği ama Türkiye virüsün yayılmasını kısa vadede engelleyebilirse tedarik zincirinde yaşanan aksaklıkları doğru stratejiler kullanarak fırsata çevirebileceği sonucuna varılmıştır.

Unmanned air vehicles (UAVs) are used successfully in many different fields mainly various military and civilian applications. Recently electric powered UAVs have become more preferable due to their better accessibility, cost, transportation and silence. However, the batteries used in electric UAVs still do not have enough energy density for long endurance flights. Due to the difficulty of using piston and gas turbine engines in small-sized UAVs, hydrogen fuel cells are seen as one of the considerable options to increase endurance and range. In this study, conceptual design of hybrid UAV including fuel cell, solar unit and battery is presented. Small, light and high endurance UAV was designed using aerodynamic calculations and minimum power requirement for cruise flight was determined. 100 W fuel cell produced by Horizon Fuel Cell Technologies and 3S, 5 Ah of battery were used for main power supplies, moreover solar cells to charge the battery were designed to mount on the surface of the wings. Also, a new power management system is designed for switching between the energy sources. As a result of this work, it is determined that fuel cells and solar units are the significant options which can increase the endurance of UAV up to 8 times depending on the design, solar flux, hydrogen capacity etc.

Additive manufacturing (AM) is a novel manufacturing technology group that revolutionizes the design and production processes behind material production. This approach is used in a wide range from simple prototypes to direct parts manufacturing in different industries such as aviation, automotive, energy, biomedical, and bioengineering. Stereolithography (SLA), fused deposition modeling, selective laser sintering, laser metal deposition approaches are the most widespread AM methods. SLA method is one of the most attractive approaches in the AM field as high-dimensional sensitivity is achieved by using liquid photosensitive resin and laser light. However, although it is possible to manufacture complex-shaped three-dimensional (3D) polymer structures with the SLA approach, the mechanical, thermal, and electrical properties are not at the desired levels. To develop more functional 3D polymer materials, various additives are dispersed into polymer structures such as metal nanoparticles, inorganic particles, fibre, carbon nanotube, and nanoclay. Titanium dioxide (TiO2) nanoparticles are a very appealing type of additive among these additives owing to their superior mechanical properties. In this study, the photosensitive resin was mixed with four different TiO2 nanoparticle concentrations (pure, 0.25, 0.5, and 1% reinforced). These slurries were then placed in the SLA device, and 3D polymer structures were fabricated. Scanning electron microscope (SEM), thermogravimetric analysis (TGA), differential scanning calorimeter (DSC), tensile tests, and Charpy impact tests were carried out to characterize mechanical, thermal, and morphological properties of developed polymer materials. It was observed that the particle size was below 1 µm and some agglomerations occurred. The elasticity modulus of the 0.5% TiO2 nanoparticle reinforced sample was measured as 694 MPa and was found to be approximately 20% higher than the pure polymer sample. In addition, polymer structures exhibited more brittle behavior. It was noted that 5% weight loss was experienced at 337 °C in all samples. Besides, the existence of unreacted carbon–carbon bonds was proven by the DSC analysis.

Yeni bir kavram olan lovemark ve kurumsal kimlik inşa etmek birçok firma için önemli bir kavramdır. Lovemark tüketicinin psikolojik etkenler doğrultusunda kurumla ilişki kurduğunu öne süren bir kavramdır. Kurum kimliğini konumlan-dırmada müşteri ile duygusal bağ kuran firmalar tüketicinin satın alma davranışını şekillendirmede psikolojik etkenlere başvurmaktadır. Firmalar tüketici ile duygusal bir bağ kurarak hem satın alma davranışı gerçekleştirmeyi hem de satın alma davranışının tekrarını sağlamayı amaçlamaktadır. Bu araştırmanın amacı ise firmaların lovemark olarak kurumsal kimliklerini nasıl konumlandırdıklarının analiz edilmesidir. Bu kapsamda Mediacat’in 2018 yılında açıkladığı lovemark firmalarından beyaz eşya ve otomobil sektöründe faaliyet gösteren 16 firmaya ait 160 adet reklam filmi incelenmiştir. Her firma için rastgele örneklem yöntemiyle seçilen on reklam filmi içerik çözümlemesi yöntemiyle analize tabi tutulmuştur. Reklam filmlerinde, kurumsal kimlik, sıra dışılık, tutku ve bağlılık boyutları ve bu boyutların birbirleri ile olan ilişkisi irdelenmiştir. Elde edilen bulgulara göre araştırmaya dahil olan firmalar, Volkswagen, Bmw, Mercedes, Renault, Ford, Fiat, Toyota, Audi ve Hyundai otomobil segmentinde; Arçelik ,Bosch, Beko ,Vestel, Samsung ,Siemens, Profilo beyaz eşya segmentinde değerlendirilmiştir. Elde edilen bulgularda firmaların reklam filmi yaratırken başta aşk, haz, güven, gibi duygusal kavramlarla satın alma davranışı için ikna edilmeye çalışıldığı gözlemlenmiştir., Lovemark, as a new concept is an important for many companies when building corporate identity. Lovemark is a concept suggestings that the consumer has a relationship with the institution in accordance with psychological factors. Companies that establish an emotional connection with the customer in positioning the corporate identity resort to psychological factors in shaping the consumer's purchasing behavior. Companies aim to achieve both purchasing behavior and repetition of purchasing behavior by creating an emotional connection with the consumer. The aim of this research is to analyze how companies position their corporate identities as lovemark. In this context, 160 advertising films belonging to 16 companies operating in the white household goods and automobile sectorfrom lovemark companies announced by Mediacat in 2018 were examined. Ten adverti-sing films selected by random sampling method for each company were analyzed by content analysis method. In advertising films, the dimensions of corporate iden-tity, uniqueness, passion and commitment and the relationship of these dimensions with each other were examined. According to the results obtained, the companies, Volkswagen, Bmw, Mercedes, Renault, Ford, Fiat, Toyota, Audi and Hyundai involved in the research were evaluated to be in the car segment; Arçelik, Bosch, Beko, Vestel, Samsung, Siemens, Profilo as white goods segment. In the results ob-tained, it was observed that companies try to convince them firms to buy behavior with emotional concepts such as love,pleasure,trust, when creating advertising films.

Hydrogen is the most abundant element in the world and produces only water vapor as a result of chemical reaction that occurred in fuel cells. Therefore, fuel cell electric vehicles, which use hydrogen as fuel, continue its growing trend in the sector. In this study, an energy distribution comparison is carried out between fuel cell electric vehicle and fuel cell hybrid electric vehicle. Hybridization of fuel cell electric vehicle is designed by equipped a traction battery (15 kW). Modeled vehicles were prepared under AVL Cruise program with similar chassis and same fuel cell stacks for regular determining process. Numerical analyses were presented and graphed with instantaneous results in terms of sankey diagrams with a comparison task. WLTP driving cycle is selected for both vehicles and energy input/output values given with detailed analyses. The average consumption results of electric and hydrogen usage is found out as 4.07 kWh and 1.125 kg/100 km respectively for fuel cell electric vehicle. On the other hand, fuel cell hybrid electric vehicle's average consumption results figured out as 3.701 kWh for electric and 0.701 kg/100 km for hydrogen consumption. As a result of this study, fuel cell hybrid electric vehicle was obtained better results rather than fuel cell electric vehicle according to energy and hydrogen consumption with 8% and 32%, respectively. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Bu çalışmada farklı güç parametrelerinde lazer kaynağı ile birleştirilen HSLA300 sac malzemelerin bükülme operasyonu sonrası geri esneme davranışına etki eden parametreler deneysel araştırılmıştır. Kaynak parametresi olarak kaynak gücü (1300, 1400 ve 1500 watt), proses parametresi olarak da kalıp açısı (15, 30, 45, 60 ve 75 derece) ve ütüleme süresi (0, 10 ve 20 saniye) deney parametreleri olarak belirlenmiştir. Kaynaklı numunelerde kaynak bölgesindeki ani soğumaya bağlı olarak yüksek miktarda martenzit fazı gözlemlenmiştir. Ancak kaynak gücünün artmasıyla birlikte HSLA yapısındaki karbon ve mangan miktarının az olmasından dolayı sertlik miktarında ve geri esneme açısında azalma meydana gelmiştir. Deneysel çalışmalarda da lazer kaynak gücünün 100 watt artmasıyla geri esneme açısının ortalama 0,15 derece azaldığı gözlenmiştir. Kalıp açısındaki 15 dereceden 45 derece açıya kadar olan artışın bükme operasyonlarında geri esneme açısını ortalama 0,14 derece arttırdığı, 45 derece açıdan 75 derece açıya kadar artışın bükme operasyonlarında geri esneme açısını ortalama 0,52 derece azalttığı gözlemlenmiştir. Ütüleme süresinin 10 saniye artmasıyla geri esneme açısının ortalama 0,14 derece azaldığı belirlenmiştir., In this study, the parameters that affect the springback behavior of HSLA300 sheet materials bonded with laser welding at different power parameters were investigated experimentally. Welding parameters (1300, 1400 and 1500 watts), die angle (15, 30, 45, 60 and 75 degrees) and holding time (0, 10 and 20 seconds) were determined as test parameters. A high amount of martensite phase was observed in welded samples due to sudden cooling in the weld zone. However, as the welding power increased, the amount of carbon and manganese in the HSLA structure was reduced, resulting in a decrease in the hardness amount and the bending angle. In experimental studies, it was observed that the springback angle decreased by 0.15 degrees with an increase of 100 watts of laser welding power. It has been observed that the increase in the die angle from 15 degrees to 45 degrees increases the bending angle in the bending operations by an average of 0.14 degrees. It was determined that the springback angle decreased by 0.14 degrees with an increase of 10 seconds holding time.

Teknolojik gelişmeler arasında üç boyutlu yazıcılar, gelecek için barındırdığı potansiyeller bakımından öne çıkan başlıklardan biri olmaktadır. Çalışmada, mobilya sektöründe üç boyutlu yazıcılarla tasarım ve yeni nesil teknolojilerle malzeme kullanımının yenilikçi mobilya tasarımlarına yönelik genel bir bakış sağlamak amaçlanmıştır. Çalışmanın içeriğinde, üç boyutlu yazıcıların günümüz çalışma prensipleri, mobilya sektöründe kullanılma olanakları, kullanılan malzemeler ve hammaddeler ile mobilya tasarım örnekleri açıklanmaktadır. Üç boyutlu yazıcılar, yeni nesil malzemeler, tasarımcıdan üreticiye ve kullanıcıya kadar sunduğu kolaylıklar, alternatifler ve yeniliklerle mobilya tasarım sektöründe gelecek için önemli potansiyeller taşımaktadır.

Yakın gelecekte petrol rezervlerinin tükeneceği öngörülmemektedir, fakat hidrokarbon kökenli yakıtların kullanılması canlılar için sağlığa olumsuz etki eden emisyonlar oluşturmaktadır. Bu nedenle dünya genelinde yenilenebilir, alternatif ve temiz enerji kaynaklarına yönelim söz konusu olmaktadır. Yakıt pilleri, sessiz ve verimli çalışabilen, aynı zamanda zararlı emisyonları olmayan bir elektrik üretecidir. Ticari uygulamaları da bulunan yakıt pilleri, havacılık, otomotiv, askeri, denizaltı yerel ve mobil uygulamalarda kullanılabilmektedir. Bu da kapsamlı bir uygulama alanı olduğunun göstergesidir. Bu çalışmada yakıt pili tiplerinden PEM yakıt pilleri araştırma konusu olarak seçilmiş ve PEM yakıt pili bileşenlerinden bipolar plakaların üretim teknikleri ele alınmıştır. Geleneksel ve yenilikçi üretim tekniklerinin araştırıldığı bu çalışmada, üretim trendinin ne aşamada olduğu tartışılmış ve konunun gelecek perspektifi göz önünde bulundurularak yapılan araştırmalar değerlendirilmiştir.

Temiz ve alternatif enerji arayışı, insanlığın sürekli artan enerji talebini karşılama doğrultusunda artış göstermektedir. Yakıt pilleri, yakıtın kimyasal enerjisini kullanarak doğrudan elektriğe dönüştüren yüksek verimli enerji dönüşüm sistemleridir. Klasik elektrik enerjisi üretim çevriminde yakıt önce yakılarak ısı enerjisi elde edilmekte, ardından buhar etkisi ile türbin döndürülmekte, jeneratörde akım elde edilmekte ve depolanmaktadır. Bu enerji dönüşümü oldukça karmaşık ve çok makineli bir sistem gerektirirken, her enerji dönüşümünde enerji kayıpları da meydana gelmektedir. Yakıt pillerinde ise sadece yakıtın elektronlarını devreden geçirerek yüksek elektriksel verimle enerji elde edilmektedir. Bu çalışmada yakıt pili çeşitlerinden PEM yakıt pilleri ele alınarak, PEM yakıt pillerinde kullanılan bipolar plakaların akış alanları incelenmiştir. Literatürde nümerik çalışmalar da bulunmakla birlikte, yakıt pillerinin oldukça değişken çalışma şartlarından dolayı deneysel olarak test etmek büyük önem arz etmektedir. Bu nedenle son on yılda yapılmış olan deneysel çalışmalar, yöntemleriyle sunulmuştur. Günümüzde çok popüler bazı akış kanalları verilmekle beraber, akış kanallarını birbirleriyle karşılaştırma yöntemiyle üstünlüğün belirlendiği anlaşılmış ve günümüzde hala optimum akış kanalına ulaşılamadığı gözlemlenmiştir.

9th International Conference on Hydrogen Production (ICH2P), WOS: 000466455000048, Last three decades, costumers and manufacturers of automotive sector have been influenced positively by Hydrogen and fuel cells (FCs). The main goal of automakers can be pointed as minimizing the fuel consumption and exhaust emissions while improving the range limits, energy efficiency and latest technology adaptation. Therewithal, electric assisted propulsion systems added to vehicles and are called as electric vehicles (EVs). For that matter, Battery Electric Vehicles (BEVs) and hydrogen Fuel Cell Electric Vehicles (FCEVs) have become the focus of researchers and producers. In this mini foreseen review, overview of the next quarter century vision of FCEVs are expressed and discussed by the helped of previous researches and with future forecast reports. The introduction part is summarized the general approach and future expectations of FCs in detailed. Technical overview is represented for FCs and FCEVs in terms of current state of technology to foreseen expectancy. Infrastructure analysis and future aspects overview part is also discussed for sector's perspective on FCEVs. The near future perspective of the FCEVs, which is seen as the next step in EVs, is discussed in detail in the next quarter century vision. Authors concluded that, between the 2030s-2050s, hydrogen FCEVs will continue their rising demand scale under the circumstances of decreasing expensive technology; enhanced energy optimization; extended range limits and increasing hydrogen refueling stations. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Stereolithography (SLA) is one of the most attractive methods in additive manufacturing approaches since obtained high dimensional sensitivity using liquid photosensitive resin and laser light. In this study, 3D polymer materials were fabricated by SLA device, and the ultraviolet post-curing process was applied at different durations (30, 60, 180, and 300 min) to investigate the effect of post-curing time on mechanical (tensile, Charpy impact tests) and thermal (DSC) properties of polymer materials. Elasticity Modulus value of post-cured polymer materials was increased by approximately 49% and achieved the level of 63.71 MPa. It was shown with the results of DSC analysis that the post-curing processes with the 180 min. and above is adequate since the carbon-carbon double bonds occurred., Sıvı fotoduyarlı reçine ve lazer ışığı kullanılarak yüksek boyutsal hassasiyetin elde edildiği Stereolitografi (SLA) yöntemi, eklemeli imalat yöntemleri arasında en dikkat çeken tekniklerden birisi olmuştur. Bu çalışmada, SLA cihazı kullanılarak 3B polimer parçalar basılmış, ikincil kürleme süresinin polimer yapıların mekanik (çekme testi, çentik darbe testi) ve termal (diferansiyel taramalı kalorimetre (DSC) analizi) özelliklerine etkisini incelemek için farklı sürelerde (30, 60, 180 ve 300 dk) UV ikincil kürleme işlemi uygulanmıştır. İşlem uygulanmış polimerlerin elastisite modülü değerinde yaklaşık %49’luk bir artış gerçekleşmiş ve 63,71 MPa mertebelerine ulaşılmıştır. DSC analiz sonuçları 180 dakika ve üzeri ikincil kürleme proseslerinin karbon-karbon çift bağlarının oluşması için yeterli olduğunu göstermektedir.

Developing technology, new technologies, and changing world standards have led researchers to search for new energy sources. In addition to countries such as America, Germany, and Japan, most automobile manufacturers have been able to adapt to changing standards, have done major researches on alternative energy vehicles, and have started to market their products. In this study, a prototype hydrogen vehicle was developed for TÜBİTAK Efficiency Challenge Electric Vehicle Organization. Design criteria were determined within the limits of the competition rule book. A computer-aided design (CAD) program was used in the vehicle shell and mechanical part designs. Vehicle flow analysis was carried out with the help of computational fluid dynamics (CFD) program. Laboratory condition long-term performance test of the fuel cell has been carried out and whether the fuel cell power was sufficient for the vehicle.

Selective Catalytic Reduction (SCR) is an emission control system used in diesel engines to reduce NOx emissions. In this study, synthesized of catalyst for SCR system was investigated as experimentally. For this purpose, silver nitrate (AgNO3), niobium (V) chloride (NbCl5) and tetra amine platinum (II) nitrate (Pt(NH3)4(NO3)2) were used to coat the cordierite (2Al2O3-5SiO2-2MgO) structure with impregnation method. X-ray Fluorescence (XRF), Scanning Electron Microscope (SEM) and Brunauer, Emmett, and Teller (BET) analyzes were carried out in order to determine the chemical and physical properties of the catalyst. Results showed that the coating materials penetrate the entire surface of the pores. It was also determined that the BET specific surface areas of the produced catalyst and cordierite are 0.2918 m2/g and 0.4568 m2/g, respectively. The reduction of surface area could be attributed to the increment of crystallization with chemical reactions occurred at the high sintering temperature. Besides, XRF analysis results demonstrated that content of Ag, Pt and Nb in the in the catalyst was found to be 3.67%, 0.19% and 0.12%, respectively, whereas Ag content in cordierite structure was 0.03%.&nbsp

Thermal comfort of an office environment is one of the most important factors affecting the performance of employees. One of the systems used in heating and cooling of offices is the radiant system...

Dizel motorlarin cevre kirliligindeki rolu cok buyuktur. Ne yazik ki, fosil yakitlarin yakilmasi hem iklim degisikligine yol acan global emisyonlari (CO2, N2O, CH4), hem de saglik acisindan olumsuz etkilere sahip olan ve dogal cevreye zarar veren bolgesel emisyonlari (PM, NOx, HC, CO, O3), beraberinde getirmektedir. Bu calismanin amaci emisyon seviyelerini dusurmek icin alternatif bir yol olarak yakitlara metal oksit esasli nano partikul katki maddesi ilave etmektir. Ayrica SCR sisteminde puskurtulen ure cozeltisi miktari degistirilerek ve ure cozeltisine %3 ve %5 oranlarinda amonyum sulfat (NH4)2SO4 eklenerek NOx emisyonlarini azaltma etkisi incelenmistir. Elde edilen neticeler sonrasinda egzoz emisyonlarini azaltmak icin uygun katki dozaj miktari tespit edilmis olup kullanilan nanopartikul katkilarinin NOx ve CO gibi zararli egzoz emisyon degerlerini azalttigi belirlenmistir.

Nowadays energy requirements have been rapidly growing due to increasing population and industrialization. Diesel engines have a huge role in environmental pollution. Harmful gas emissions increase along with energy consumption, therefore, new ways to restrict harmful gases and to take precautions are sought. In this study, MgO nanoparticle additive with extra oxygen content were used in diesel fuel in compression ignition engines, in order to monitor fuel properties, performance and emission values. Dosage of additive into diesel fuel were 25, 50 and 100 ppm and the optimum dosage of additives was determined in relation to decrease of NOx and CO emissions. Article DOI: https://dx.doi.org/10.20319/mijst.2017.33.7285 This work is licensed under the Creative Commons Attribution-Non-commercial 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc/4.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.

Conventional fossil fuel sources face with scarcity risk. Therefore, researchers are trying to find new renewable alternative energy sources which have potential to replace conventional sources. Alcohol and biodiesel are prominent sources among others. In this study, performance and emission characteristics of a diesel fuel and ethanol added (20% vol.) diesel fuel (E20) operated compression ignition engine was studied in between 1000 - 2600 engine speed. Torque, power, specific fuel consumption curves as performance and carbon monoxide (CO), nitrogen oxides (NOx) curves as emission parameters with respect to engine speed were obtained. Energy and exergy efficiency curves versus engine speed in order to assess the system thermodynamically were also obtained. Results showed that, while torque, power, CO emission were decreased, specific fuel consumption, NOx emission were increased with use of diesel-ethanol blends. On the other hand, both energy and exergy efficiency values were decreased when alcohol was added to diesel fuel. Article DOI: https://dx.doi.org/10.20319/mijst.2017.33.5161 This work is licensed under the Creative Commons Attribution-Non-commercial 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc/4.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.

In this study, emissions of compression ignition engine fueled by diesel fuel with nanoparticle additives was modeled by regression analysis, artificial neural network (ANN) and adaptive neuro fuzzy inference system (ANFIS) methods. Cetane number (CN) and engine speed (rpm) were selected as input parameters for estimation of carbon monoxide (CO), oxides of nitrogen (NOx), and carbon dioxide (CO2) emissions. The results of estimation techniques were compared with each other and they showed that regression analysis was not accurate enough for prediction. On the other hand, ANN and ANFIS modelling techniques gave more accurate results with respect to regression analysis; linear and non-linear. Especially ANFIS models can be suggested as estimation method with minimum error compared to experimental results.

With the ever-growing aviation industry, energy researches on aviation have turned to renewable energy sources providing electric propulsion. Fuel cells are one of the most popular sources of power for electric vehicles terms of being greener, more reliability, and higher efficiency. Among fuel cells, the most attractive option for flight is polymer electrolyte membrane fuel cells (PEMFC). This paper aims to compose of a hybrid propulsion system to a lightweight aircraft Cri-Cri for more electric aircraft concept. For this purpose, first, conceptual a hybrid propulsion system is designed for the prototype aircraft. The fuel-cell hybrid system proposed for this paper consists of electric motor, fuel cell system, battery, DC/AC converter, and DC/DC converter. Second, some analyses are done. These analyses contain required power, hydrogen consumption, energy consumption, etc.. As a result, Cri-cri needs 26 Kw during take-off, 30 Kw during climb, 10 kW during cruise, and 7 kW during descent. It also consumed 0.75 kg of hydrogen in total, including 0.21 kg in the take-off and climb, 0.42 kg in the cruise, and 0.12 in the descent. The remaining 0.25 kg of hydrogen is reserved for use in emergencies. The total amount of energy consumed is 33 kWh.

Formability and springback behaviours of dual-phase 600 (DP600) sheet material bonded with laser welded in different power parameters were investigated experimentally. In the first stage of the study, springback behaviours of non-welded DP600 sheet material were investigated. In the next stage of the study, springback behaviours of DP600-DP600 samples, which were bonded with three different power parameters (1400 watts, 1500 watts, 1600 watts) by welding, were investigated by bending in V bending dies. Die angle (15, 30, 45, 60 and 75 degree) and holding time (0, 10 and 20 s.) were determined as process parameters in the study. In higher welding powers, it was observed that both the melting zone and the heat-affected zone were expanded. Then ferrite phases in these expanding zones have been transformed into martensite phase. This case provided to increase the stiffness and thereby improved the spring-capability. Because of increase hardness due to the increase in laser welding power, average springback angle of welded sheet increased by 5.72%. In addition die angle is one of the parameters that strongly change the springback angle. Negative springback was observed at the die angle of 15 degrees. It was found that the springback angle increased on an average of 57.2% as the die angle was increased from 30-degree to 45-degree. On the other hand, the springback angle decreased on an average of 18.7% as the die angle was increased from 45-degree to 75-degree. This case is due to the conglomerating of the stresses in a narrow space after a 45-degree die angle. Depending on the increase in holding time, the springback angle decreased by 10.05% because of an increase of residual stresses.

This study experimentally investigated the formability and springback behavior of dualphase (DP600) and high-strength low-alloy (HSLA) sheets bonded with a laser beam welding. In the initial stage of the study, DP600 and HSLA sheets were bent in V-bending dies and their springback behavior was investigated. In the later stage of the study, DP600-HSLA sheets bonded with a laser of three different power levels (1400 W, 1500 W, 1600 W) were bent in V-bending dies to investigate their springback behavior. In addition, changes in the metallurgical structure were investigated at the points where the pieces were welded together and the effect on springback characteristics was evaluated. As the power of laser increased from 1400 to 1500 W, the springback angle increased by 12.1% on average, whereas when the power was increased from 1500 to 1600 W, the springback angle decreases by 17.6%. An increase of 15 degrees in the die angle increases the springback angle by 10.4% on average up to 45 degrees; whereas beyond 45 degrees, it decreases the springback angle by an average of 73.6%. For a 10-s increase in holding time, it was determined that springback angle decreased by 21.2% on average.

Noise is a very important phenomena for passenger comfort in a vehicle. Engine of the vehicles produce disturbing noises in different frequencies. In the application of acoustic, there are different filters to predict the sound pressure level and disturbing noises. The aim of the present study is to investigate the noise characteristic of a compression ignition engine at different weighting filters. In the experiments, the engine was fuelled with low sulphur diesel and sunflower biodiesel fuels and it run at different engine speeds ranging from 1200 to 2400 rpm, with steps of 300 rpm. The results indicated that noise characteristic of compression engine with engine speed shows different trends at A- weighting filter than C- and Z- weighting filters especially at 1500 rpm. Moreover, in the study, it was cleared that the SPL decrease with the addition of biodiesel fuel regardless of its ratio.

Katmanlı imalat teknolojisine olan ilgi son yıllarda artış göstermektedir. Katmanlı imalat tekniği, geleneksel imalat yöntemlerinin aksine malzeme eksiltme değil de, malzeme eklenmesi prensibine dayanmaktadır. Yüksek tasarım serbestliği, artık malzeme oluşmaması, kullanıcıya özel ürünlerin imal edilebilmesi, tasarımdan imalata geçiş süresinin düşük olması, hücresel yapılar ve optimum tasarımlar ile daha hafif ürün elde edilebilmesi katmanlı imalat tekniğinin avantajlarındandır. Bunun yanında katmanlı imalat tekniğinin bir takım dezavantajları da bulunmaktadır. Bunlardan bir tanesi katmanlı imalat ile üretilen ürünlerin boyutlarının sınırlı olmasıdır. Araştırmacılar bu problemi ortadan kaldırmak amacıyla katmanlı imalat tekniği ile üretilen metalik malzemeleri kaynak yöntemiyle birleştirerek çalışmalar yapmaktadır. Bu çalışmada lazer ergitme-sinterleme ve elektron ışını ergitme yöntemleri kullanılarak üretilen malzemelerin kaynak kabiliyetinin araştırıldığı çalışmalar derlenmiştir., The interest in additive manufacturing technology has increased in recent years. The additive manufacturing technique is based on the principle of adding material, not material reduction, as opposed to conventional manufacturing methods. High design freedom, no residual material, the manufacture of user-specific products, the low transition time from design to manufacturing, the ability to obtain lighter products with the cellular structures and optimum designs are among the advantages of the additive manufacturing technique. In addition, there are some disadvantages of the additive manufacturing technique. One of them is the limited size of the products produced by additive manufacturing. In order to eliminate this problem, researchers have been working by joining the metallic materials produced by the additive manufacturing technique with the welding method. In this study, studies on the welding ability of the materials produced by using laser melting-sintering and electron beam melting methods were collected.

Bu çalışmada sac metal malzemelerin oda sıcaklığında bükülerek şekillendirilmesi sonrası gözlenen ve şekillendirmede istenmeyen bir durum olan geri esneme davranışı deneysel olarak araştırılmıştır. Çalışmada DP600 ve HSLA300 sac malzemeler farklı kalıp açılarında ve ütüleme sürelerinde V bükme yöntemiyle şekillendirilmiştir. Çalışma sonunda ütüleme süresinin 10 saniye artmasıyla elastik gerilmelerin kalıcı gerilmelere dönüşmesinden dolayı geri esneme açısının DP600 sac malzemede ortalama %14,8, HSLA sac malzemede ise ortalama %9,7 azaldığı tespit edilmiştir. Kalıp açısının artmasıyla elastik gerilim miktarının da artmasından dolayı her iki malzemede de esneme açısının arttığı, açının büyümesiyle de elastik gerilmelerin dar bir alanda hapsolmasından dolayı da esnemenin daha sonra azaldığı belirlenmiştir. DP600 sac malzemede 15 derece kalıp açısından 45 derece kalıp açısına kadar esnemenin ortalama %15,2 arttığı, 45 dereceden sonra ise %27,6 azaldığı tespit edilmiştir. HSLA sac malzemede ise 15 derece kalıp açısından 30 derece kalıp açısına kadar esnemenin önce ortalama %10,4 arttığı, 30 dereceden sonra ise %26,4 azaldığı gözlenmiştir. Ayrıca DP600 sac malzemenin sertliğinin HSLA sac malzemeden daha yüksek olmasından dolayı oluşan geri esneme değerinin HSLA sac malzemeye göre %12,3 daha yüksek olduğu belirlenmiştir., The springback behaviour which is undesirable situation after the bending operation in room temperature was experimentally investigated. DP600 and HSLA sheet materials were formed by V-bending method in different bending angle and holding time. Due to transformation of elastic stress to permanent stress 10 second increasing in the holding time were caused to decrease in springback angle in 14.3% for DP600 and in 9.7% for HSLA sheets. Increasing the bending angle were caused to increase in springback angle both material due to increasing elastic stress. However, more increasing the bending angle were caused to decrease in springback angle both material due to summing of elastic stresses in narrow angle. In DP600 material, its observed that increasing the die angle from 15 degrees to 45 degrees were caused to 15.2% increase the springback angle but after the 45 die angle the springback angle decreased 27.6% degree. In HSLA300 material, its observed that increasing the die angle from 15 degrees to 30 degrees were caused to 10.4% increase the springback angle but after the 30 die angle the springback angle decreased 26.4% degree. In addition to, its determined that due to the higher hardness of DP600 sheet metal than HSLA sheet metal, the springback angle for DP600 higher 12.3% than HSLA 300 sheet material.

Noise and vibration of ignition compression engine is one of the most complicated field to cope with since every mechanism that compose of the engine affect them separately. In this study, effect of various biodiesel on engine noise and vibration has been studied on an unmodified compression ignition engine. Linear and non-linear based regression analysis based models were also developed to predict the relationship between fuel properties and noise-vibration of the engine with excellent agreement. The results revealed that noise and vibration of the engine decreased with increasing biodiesel ratio until pure biodiesel usage and in linear regression analysis, correlation coefficient (R) values were 0.784 and 0.741 for vibration and sound pressure level, correspondingly. In non-linear regression analysis, correlation coefficient (R) values were 0.814 and 0.777 for vibration and sound pressure level, correspondingly. In linear regression analysis, mean absolute percentage error (MAPE) values were 0.747% and 0.126% for vibration and sound pressure level, correspondingly. In non-linear regression analysis, mean absolute percentage error (MAPE) values were 0. 682% and 0.342% for vibration and sound pressure level, respectively. © 2016 Elsevier Ltd. All rights reserved.

PubMedID: 26759925 Objective: Currently, in Turkey, fault rates in traffic accidents are determined according to the initiative of accident experts (no speed analyses of vehicles just considering accident type) and there are no specific quantitative instructions on fault rates related to procession of accidents which just represents the type of collision (side impact, head to head, rear end, etc.) in No. 2918 Turkish Highway Traffic Act (THTA 1983). The aim of this study is to introduce a scientific and systematic approach for determination of fault rates in most frequent property damage–only (PDO) traffic accidents in Turkey. Methods: In this study, data (police reports, skid marks, deformation, crush depth, etc.) collected from the most frequent and controversial accident types (4 sample vehicle–vehicle scenarios) that consist of PDO were inserted into a reconstruction software called vCrash. Sample real-world scenarios were simulated on the software to generate different vehicle deformations that also correspond to energy-equivalent speed data just before the crash. These values were used to train a multilayer feedforward artificial neural network (MFANN), function fitting neural network (FITNET, a specialized version of MFANN), and generalized regression neural network (GRNN) models within 10-fold cross-validation to predict fault rates without using software. The performance of the artificial neural network (ANN) prediction models was evaluated using mean square error (MSE) and multiple correlation coefficient (R). Results: It was shown that the MFANN model performed better for predicting fault rates (i.e., lower MSE and higher R) than FITNET and GRNN models for accident scenarios 1, 2, and 3, whereas FITNET performed the best for scenario 4. The FITNET model showed the second best results for prediction for the first 3 scenarios. Because there is no training phase in GRNN, the GRNN model produced results much faster than MFANN and FITNET models. However, the GRNN model had the worst prediction results. The R values for prediction of fault rates were close to 1 for all folds and scenarios. Conclusions: This study focuses on exhibiting new aspects and scientific approaches for determining fault rates of involvement in most frequent PDO accidents occurring in Turkey by discussing some deficiencies in THTA and without regard to initiative and/or experience of experts. This study yields judicious decisions to be made especially on forensic investigations and events involving insurance companies. Referring to this approach, injury/fatal and/or pedestrian-related accidents may be analyzed as future work by developing new scientific models. © 2016 Taylor & Francis Group, LLC.

6th International Conference on Progress in Hydrogen Production and Applications (ICH2P), WOS: 000376695800066, Main objective of this study is to compare performance and emission characteristics of a pilot injection diesel engine with the additions of alternative fuels like pure hydrogen, HHO and biodiesel. In order to achieve this goal, Helianthus annuus (sunflower) biodiesel was produced and blended with volumetric ratio of 10% with diesel fuel. Additionally, intake air was enriched with pure hydrogen or HHO via intake manifold without any structural changes except reduction of injected diesel fuel on the 3.6 L, four cylinders, four stroke diesel engines. Amount of Hydrogen fuel supplied to the engine was adjusted to constant 10 L/min during the experiments. The effects of pure hydrogen and HHO usage with the addition of biodiesel to the engine performance values (Brake Torque, Brake Power and Brake Specific Fuel Consumption) and exhaust emission values (NOx, CO2, CO) were investigated in between 1200 and 2600 rpm engine speeds. Engine performance values were increased with the enriching the intake air with HHO than pure hydrogen compared to the standard diesel fuel operating condition. On the other hand, in terms of exhaust gas emissions, pure hydrogen provided better results than HHO. In both cases, changes on the engine performance results were minimal however improvements on exhaust gas emissions were very promising. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

6th International Conference on Progress in Hydrogen Production and Applications (ICH2P), WOS: 000376695800067, In this experimental study, Hydroxy (HHO; Oxy-hydrogen) - CNG (Compressed Natural Gas) fuel mixtures were used as an additional fuels in a non-modified diesel engine via intake manifold by substitution of diesel fuel. Three cases of experiment performed in a 3.6 L, four cylinders, four stroke diesel engine; first case is non-substitute liquid fuel, neat diesel operation; second case is HHO (5.1 lpm) addition to air mixture and operated under substituted diesel engine and third case is 25HHO-CNG mixture (25% Hydroxy-75% CNG-(5.1-15.3 lpm)) inducted the intake manifold and running with substituted diesel engine. During the tests stepping motor and driver used on fuel pump plunger to substitute diesel fuel as similar to pilot diesel injection. The effects of HHO and HHOCNG fuels relative to neat diesel operations were investigated in between 1200 and 2600 rpm engine speeds and expressed on both engine performance values like; brake torque, brake power, brake specific fuel consumption and brake thermal efficiency; and exhaust emissions; NOx, CO2, CO and exhaust gas temperature (EGT). Results showed that the addition of HHO-CNG mixture is most effective in improving the engine performance and providing more environmentally friendly attitude on exhaust emissions compared to neat diesel operations. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

3rd International Hydrogen Technologies Congress (IHTEC) -- MAR 15-18, 2018 -- Alanya Alaaddin Keykubat Univ, TURKEY, WOS: 000477092000033, One of the primary aims of this experimental investigation is to examine hydroxy-gas enrichment effects on environmentally friendly but performance-reducing alternative fuels such as ethanol and biodiesel. Hydroxy gas is a product of the pure water electrolysis method. Entire HHO system has integrated into engine test rig for this purpose. Two different biodiesohol fuel blend prepared and named by their volumetric compositions. Biodiesohol used to describe biodiesel, ethanol and standard diesel blends. Specific fuel properties are measured and ensured to be in EN590 and EN14214 standards. Experiments were conducted on a single cylinder diesel engine which was fuelled with diesel-biodiesel-ethanol fuel blends those enriched by 1 L per minute HHO gas during the entire tests. All of the experiments performed under full load condition within the range of 1200-3200 rpm engine speed. From the view of performance; brake power, brake specific fuel consumption and thermal efficiency results discussed. Besides, carbon monoxide and nitrogen oxides results measured and presented as exhaust emission. Standard diesel fuel outputs determined as a reference line to analyze the changes. A number of studies have been conducted with fuels used in this experimental study and their mixture in different ratios as well, but an examination of the HHO addition to biodiesel is performed for the first time in this research area of the literature. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

8th International Conference on Modeling Simulation and Applied Optimization, ICMSAO 2019 -- 15 April 2019 through 17 April 2019----153127 Fuel cells which are electrochemical devices have gained popularity in last three decades as an alternative energy resource. Especially PEM fuel cells (proton exchange membrane or polymer electrolyte membrane) are one of the most developed fuel cell types and use in transportation (automotive) applications. Bipolar plates (BPs), on the other hand, responsible for distribution of reactant gases and collect of current in PEM fuel cell stack. Flow channels mill on bipolar plates for the purpose of distribution of gases to the fuel cell system. These flow channel patterns can be different types such as parallel, serpentine, grid, spiral, cascade. In addition, bipolar plates manufacture from graphite materials usually owing to its superior features such as high electrical conductivity high and corrosion resistance. Besides, they can be manufacture from metallic plates, alloys and composite materials. In present study, carbon/epoxy laminated composite BP models were prepared with four different flow channel patterns (parallel, serpentine, grid and spiral) and four different stacking sequences of reinforced plies. After, the effects of fibre orientations and flow channel patterns on the carbon/epoxy laminated composite BPs were investigated numerically under thermal loads. Deformations of the models and the stresses on the models were evaluated. ANSYS® is used to model the laminated composite models and to perform numerical thermal analysis. Warping of the BPs was determined by benchmarking intact and deformed models and the optimum flow channel pattern. © 2019 IEEE. 18103014 Authors acknowledge the financial support provided by the Adana Science and Technology University Scientific Research Unit through the project #18103014.

With the application of a data processing and reporting system, the vehicle had capability of processing, sending, and reporting data in the vehicle as requested by the driver, owner, and/or fleet management center via Internet. This data can be saved and monitored online by the fleet management center via Internet. By processing this data, performance of drivers of the fleet can also be evaluated.

WOS: 000370306300103, Pilot diesel injection phenomenon consisted by gaseous fuels such as hydrogen and natural gas; ensure the way of exert fuels without any structural modification in compression ignition engines. This study investigates of using 30HCNG (Hydrogenated Compressed Natural Gas) fuel mixture on a non-modified diesel engine operated with diesel fuel replacement rate experimentally. HCNG was used as an additional fuel with air fumigation in a non-modified diesel engine via intake manifold and reduction of diesel fuel by dint of pilot injection. Reduction of diesel fuel was prepared as two different substitutions like 25 and 50% diesel replacement rates controlled by stepping motor devices. 30% Hydrogen and 70% CNG (Compressed Natural Gas) (by volumes) fuel mixture were tested in a 3.6 L, four cylinders, four stroke and water coolant diesel test engine between 1200 and 2600 rpms. Effects of these two different diesel reductions on engine performance and exhaust emissions parameters were compared and illustrated with graphics as brake power, brake torque, and brake specific fuel consumption; CO, CO2 and NOx. Brake thermal efficiency and a minor cost analyses were also performed. It was observed that, 30HCNG fuel mixture with 50% diesel replacement rate affect the engine performance as brake torque, brake power and BSCF values were decreased 4.3%, 8%, 26.8% respectively. Exhaust emission values of NOx and CO2 were decreased 47.2%, 16.7% respectively; however CO emission values were increased 8%. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved., TUBITAK (The Scientific and Technological Research Council of TURKEY) [114M798], This work is a part of a project under grant number "114M798" which is supported and funding by TUBITAK (The Scientific and Technological Research Council of TURKEY).