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Now showing 1 - 10 of 447
  • Article
    Citation - WoS: 4
    An Eye-Controlled Wearable Communication and Control System for Als Patients: Smarteyes
    (Yildiz Technical Univ, 2017) Sumer, Emre; Uslu, I. Baran; Turker, Mustafa
    ALS (Amyotrophic Lateral Sclerosis) is a progressive neurodegenerative disease that involves the malfunctioning of motor neurons. The ability of the brain to initiate and control muscle movement is lost subsequent to death of motor neurons. People with ALS present the greatest challenge regarding communication issues. Besides, caring for a loved one with ALS is not an easy task. In this study, we developed an eye-controlled wearable system called "SmartEyes" which improves the life qualities of ALS patients and their caregivers by offering two important skills. The first skill is communicating through predefined voice messages generated by a computer and the second one is controlling several peripherals located in the patient's environment. The developed system is novel in that; the patients can easily vocalize their needs and requests with a few sequential eye movements. Moreover, they can control several household items including desk lamp, rolling curtain, television and air conditioner in the same way. The preliminary experiments showed that the performance of the system is satisfactory. The accuracy of the system commands based on pupil gaze direction was tested on several users and about an accuracy of 89% was achieved. It is believed that the developed system has attracted the patients' and their caregivers' interest very much and this is the main motivation in improving our system.
  • Conference Object
    Citation - WoS: 1
    Operator Splitting of the Kdv-Burgers Type Equation With Fast and Slow Dynamics
    (Amer inst Physics, 2010) Aydin, A.; Karasozen, B.
    The Korteweg de Vries-Burgers (KdV-Burgers) type equation arising from the discretization of the viscous Burgers equation with fast dispersion and slow diffusion is solved using operator splitting. The dispersive and diffusive parts are discretized in space by second order conservative finite differences. The resulting system of ordinary differential equations are composed using the time reversible Strang splitting. The numerical results reveal that the periodicity of the solutions and the invariants of the KdV-Burgers equation are well preserved.
  • Conference Object
    Citation - WoS: 3
    Synthesis of Tio2 Nanostructures Via Hydrothermal Method
    (John Wiley & Sons inc, 2015) Bilgin, Nursev; Agartan, Lutfi; Park, Jongee; Ozturk, Abdullah
    Titania (TiO2) nanostructures were produced via hydrothermal method using amorphous TiO2 powders synthesized by the sol-gel precipitation process. The hydrothermal system was isolated from the environment and hydrothermal reactions were allowed to execute at 130 degrees C for 36 h at autogeneous pressure, and at a stirring rate of 250 rpm. Scanning electron microscopy (SEM) analysis revealed that TiO2 nanofibers formed instead of nanotubes upon utilization of amorphous TiO2 precursor. After hydrothermal synthesis, the powders were acid treated by HCl several times. X-ray diffraction (XRD) analysis identified that the synthesized powders were Na-titanate and remained Na-titanate even after subjecting to acidic treatments several times. The photocatalytic performance of the powders was evaluated by degradation of methylene blue (MB) solution in UV illumination. Results were compared with nanotubes which were synthesized previously using P25 commercial titania powder and have shown that TiO2 in tubular structure offers better photocatalytic performance for the degradation of MB solution under UV illumination as compared to fiber-like structure.
  • Article
    Citation - Scopus: 1
    Evaluation of Rebound Hammer Test as a Combined Procedure Used With Drill Core Testing for Evaluation of Existing Structures
    (2012) Yeşilmen,S.
    Rebound hammer is a non-destructive test method often used to assess the surface hardness of engineering materials. The method is used as a part of the procedure applied to evaluate existing structures. The concrete core tests are usually combined with rebound hammer tests to decrease costs and damage to the structure. Various studies attempted to establish a reliable relationship between the concrete strength and the rebound coefficient. Proposed formulas and correlation coefficients stayed reliable for narrow limits on factors like concrete age, composition, moisture content, etc. Despite the high uncertainty of the raw data the methodology remains in use. This paper presents the evaluation of rebound hammer and drill core test data from 256 different buildings in Antalya, Turkey. With uncontrolled parameters like environmental factors, age, compressive strength of concrete, the rebound hammer test results showed very little correlation with concrete core test results even for the statistically large data set. © RILEM 2013.
  • Article
    Citation - WoS: 9
    Citation - Scopus: 12
    Some Integral Type Common Fixed Point Theorems Satisfying Φ-Contractive Conditions
    (Belgian Mathematical Soc Triomphe, 2014) Chauhan, Sunny; Karapinar, Erdal
    In this manuscript, we obtain some common fixed point results of two pairs having the common limit range property in the setting of integral type contraction in the framework of symmetric (semi-metric) spaces. Moreover, we extend our results from two pairs of self-mappings to four finite families of self mappings to get common fixed points. Our results improve and extend a host of previously known results. Further, we establish some illustrative examples to show the validity of the main results.
  • Article
    İKİ KATMANLI DOLU BİR SİLİNDİRİN ELASTİK DAVRANIŞININ FARKLI UÇ VE SINIR KOŞULLARI İÇİN ANALİTİK OLARAK İNCELENMESİ
    (Turkish Soc thermal Sciences Technology, 2020) Akış, Tolga; Eraslan, Ahmet N.
    İki katmanlı dolu silindirlerin zamana bağlı termoelastik davranışlarının farklı uç ve sınır koşulları için belirlenmesi amacıyla analitik modeller geliştirilmiştir. Söz konusu silindirler, aralarında mükemmel temas olan ikikatmandan oluşmaktadır. Başlangıçta sıcak olan silindir, yüzeyinden konveksiyon yolu ile sıfır derecelik çevreselsıcaklığa veya önceden daha düşük olarak belirlenen yüzey sıcaklığına ulaşana kadar enerji kaybetmektedir. Tümdurumlarda soğuma yavaş bir biçimde gerçekleştiğinden problemde kuplajsız elastisite teorisinin kullanılması mümkünolmuştur. Genelleştirilmiş düzlemsel şekil değiştirme çözümü elde edilmiş ve bu çözüm, eksenel yöndeki birim şekildeğiştirmeyi sıfıra eşitleyerek düzlemsel şekil değiştirme durumuna ait çözüme indirgenmiştir. Bu çözümlere aitsonuçlar, sınır koşullarının serbest olduğu durumlarda radyal ve teğetsel yöndeki gerilmelerin uç koşullarına göredeğişmediğini göstermiştir. Ancak düzlemsel şekil değiştirme durumunda, eksenel gerilme baskın gerilme olmakta veuçların serbest olduğu duruma göre oldukça yüksek değerlere ulaşmaktadır. Kompozit silindirin eksenel ve radyalyönde yer değiştirmesinin kısıtlanması büyük gerilmelere yol açmasına rağmen ilgili gerilme durumu silindirde akmayayol açmamaktadır.
  • Article
    Vahdet-i Mevcut’tan Vahdet-i Vücud’a: Anadolu’da İslam Dönemi Sonrasındaki Tanrı Algısının Semah ve Sema Kavramları Aracılığıyla İncelenmesi
    (2012) Güray, Cenk
    Anadolu’da yaşamış olan tüm uygarlıklar, bu coğrafyaya maddi ve manevi izler bırakmışlardır. Toplumların yaşamsal geleneklerinin önemli bir kısmında etkin bir rol oynayandin ve inanç kültürüne dair simgeler, bu topluluklardan kalmış manevi izlerin en önemlileriarasındadır. Müziğin ve dansın ifade gücü, onları her inanç sistemi için oldukça çekici aktarım araçları haline getirmiştir. Anadolu için inanç ve müzik ilişkisini gerek tarihsel derinlikgerekse de coğrafi yaygınlık açısından en geniş şekilde tanımlayan iki kavram olan semahve sema’nın altyapılarında yatan Vahdet-i Mevcut ve Vahdet-i Vücud felsefeleri aracılığıylaanalizi, Anadolu tarihinin değişik dönemlerindeki insan- Tanrı ilişkisinin dini müzik ve dansyoluyla çözümlenebilmesi için önemli imkânlar sunmaktadır. Bu bağlamda Vahdet-i Mevcutfelsefesinden daha yoğun bir biçimde etkilenmiş olan semah kavramı içinde Tanrı’nın somutolarak tezahürü simgelenirken, bu tezahür Hz. Ali’nin kişiliği aracılığı ile yansıtılmaktadır.Diğer yandan, Vahdet-i Vücud felsefesi doğrultusunda yapılanan sema geleneği içinde iseTanrı’nın bilgisine ulaşarak aşama aşama olgunlaşma gayreti mevcuttur. Ancak sema’da,Tanrı’nın insan vücudunda tezahür etmesi ya da kişileşmesi simgesine rastlanmamakta, sadece insanın maddi ve manevi dünya arasındaki yolculuğu ve bu yolculukta geçirdiği olgunlaşma evreleri ifade edilmektedir. Semah bu anlamıyla vecd ve coşku ile Tanrı ile bir olma,sema ise olgunlaşma, bilgiye mazhar olma ve çile ile Tanrı’nın bilgisinden pay alma anlayışlarını simgelemekte ve iki ayrı insan-Tanrı ilişkisini yani Tanrı algısını ortaya koymaktadır.
  • Conference Object
    Attitude Control of Cubesat in Single Axis by Fuzzy Logic Controller
    (Avestia Publishing, 2017) Nazlibilek,S.; Kilickaya,O.G.; Tanyer,S.G.
    Over the last two decades, satellites are getting smaller with increasing capabilities for space research. Small satellites (between 1 and 15 kg) show great promise as a low-cost option both in production and launching. In this work, attitude control problem for a cubesat is examined. A physical testbed is designed for simulation and testing in a single axis. Cubesat reaction wheel and the testbed are integrated, and fuzzy logic control software in Arduino Mega microprocessor environment is developed. The cubesat floor at the same axis of reaction wheel is tested and real-time measurement data are obtained. Step response and ramp response behaviours are analysed. © 2016 Avestia Publishing.
  • Book Part
    Citation - Scopus: 1
    Materials and Processes for Treatment of Microbiological Pollution in Water
    (Springer, 2021) Alazzawi,M.; Turkoglu Sasmazel,H.
    Clean and safe water is vital for the life and health of human beings. However, there are still millions of people around the world with inadequate clean water sources. Microbiological pollution is one of the most concerned water pollutants and is the crucial cause of waterborne diseases like diarrhea, resulting in about two million deaths annually due to severe dehydration (WHO in Guidelines for drinking-water quality. Incorporating the first addendum, WHO, Geneva, 2017). It is critical to develop methods using advanced materials and process to mitigate contaminants from water resources. Production of safe water usually involves disinfection and decontamination processes. Conventional disinfection process, such as chlorination, is challenged by the formation of disinfection by-products. Furthermore, the presence of emerging pathogenic, that resist conventional water treatment techniques, raised the crucial necessity for emerging materials and techniques for treating water from microbiological pollution (Shannon et al. in Nature 452:301–310, 2008). This chapter describes bacterial, viral, and protozoal microbiological pollution in water supplies and the application of emerging materials and techniques to eliminate such contaminations. © 2021, Springer Nature Switzerland AG.
  • Article
    Citation - WoS: 6
    A Light Bulb in Every House the Istanbul General Electric Factory and American Technology Transfer To Turkey
    (Johns Hopkins Univ Press, 2022) Tunc, Tanfer Emin; Tunc, Gokhan
    In 1946, Turkish entrepreneur Vehbi Koc signed an agreement with the U.S. firm General Electric to build and operate its first light bulb factory in the Near/Middle East, in Istanbul. This private joint venture introduced new manufacturing techniques, business practices, and consumer habits to Turkey, opening channels of postwar technological exchange. Closer examination of the GE-Koc partnership reveals that during the early Cold War, the transfer and embedding of American technologies in Turkey was a politically complicated process of innovation that required constant adaptation. Fraught with unforeseeable obstacles, it also required cautious negotiation with multiple transnational actors. The story of the GE-Koc partnership thus adds a new dimension to historical understandings of the Turkish Cold War experience and the Americanization of the region. It illustrates how transferring a nonmilitary, soft-power, domestic technologythe light bulb-played a significant role in Turkish-American relations and therefore contributes to studies of U.S. Cold War diplomacy through transnational investment in innovation.