Sürdürülebilir Yeşil Kampüs Koleksiyonu / Sustainable Green Campus Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7755

Browse

Filters

2007 - 200962010 - 20187

Settings

Publication Index: search.filters.publicationIndex.ScopusPublisher: search.filters.publisher.Institute of Electrical and Electronics Engineers Inc.

Search Results

Now showing 1 - 10 of 13
  • Conference Object
    Citation - WoS: 1
    Citation - Scopus: 1
    Cell Load Based User Association for Tetra Trunk Systems
    (Institute of Electrical and Electronics Engineers Inc., 2018) Karataş, Azad; Özbek, Berna; Bardak, Erinç Deniz; Sönmez, İlker
    Increasing traffic in communication systems need efficient new cell selection algorithms to control the distribution of users. For better and seamless transmission, load balancing become critical factors for cell selection algorithms. Un-desired consequents in these situations may cause disasters specifically for the emergency cases in public safety services. In this paper, a cell selection algorithm is proposed for Terrestrial Trunked Radio (TETRA) based Professional Mobile Radio (PMR) systems. The proposed algorithm is designed to provide a fairer distribution of users among cells while keeping the number of received power measurement less. The performances of the proposed algorithm are obtained in urban and rural environment.
  • Conference Object
    Üç Boyutlu Hücre Kültürü için Polimer Esaslı Ekstrasellüler Matriks Mimetiği
    (Institute of Electrical and Electronics Engineers Inc., 2017) Türker, Esra; Yıldız, Ümit Hakan; Arslan Yıldız, Ahu
    Elektro-eğirme metodu gelişmiş üretim teknolojilerindendir ve biyomedikal uygulamalarında yaygın olarak kullanılmaktadır. Özellikle doku mühendisliğinde amaç, çalışılacak doku üzerine doğal veya sentetik destek materyali (iskele) üreterek hücrenin uyum sağlayabileceği bir ortam oluşturmaktır. Bu projenin amacı üç boyutlu (3D) hücre kültürü çalışmaları için elektro-eğirme-metodu ile poli(L-laktik-co-epsilon-kaprolakton) (PLLCL) kullanılarak iskele üretilmesidir. Homojen lifler ve uygun gözenek boyutu elde etmek amacıyla optimizasyon çalışmaları yapılmıştır. Elde edilen liflerin çapı, akış hızı ve voltajın artmasıyla azalmaktadır. Taramalı uç elektron mikroskop incelemeleri (SEM) lif morfolojik yapılarının doku iskelesi fabrikasyonu için ideale yakın olduğunu ortaya çıkarmıştır.
  • Conference Object
    Yazılım Tabanlı Radyolarda Karşılıklı Kanal Özelliğinin İncelenmesi
    (Institute of Electrical and Electronics Engineers Inc., 2016) Uslu, Merve; Tuğrel, Halim Bahadır; Karabulut Kurt, Güneş; Özbek, Berna
    Kablosuz haberleşme sistemlerinde, kanal kestirimi çok önemli bir yer tutmaktadır. Bu çalışmada A ve B, iki haberleşme düğümü olduğu varsayıldığında, A düğümünden B düğümüne olan kanal için elde edilen kanal katsayıları ile, B düğümünden A düğümüne olan kanal için elde edilen kanal katsayılarının benzerliği incelenmiştir. Karşılıklı kanal özelliğinden dolayı bu kanalların birbirine benzer çıkmaları beklenmektedir. Bu çalışmada, laboratuvar ortamında yazılım tabanlı radyo kitleri kullanılarak karşılıklı kanal özelliği test ortamında test edilmiş, bu iki kanal katsayılarının genlik ve faz ortalama değerleri karşılaştırılmıştır.
  • Conference Object
    Citation - Scopus: 2
    Resource Allocation for User-Relay Assisted Miso-Ofdma Networks
    (Institute of Electrical and Electronics Engineers Inc., 2015) Baştürk, İlhan; Özbek, Berna
    The next generation cellular networks request higher capacity and coverage that user-relay assisted Orthogonal Frequency Division Multiple Access (OFDMA) networks are costeffective solutions to meet these demands. These networks can be enriched with multiple antennas in order to obtain a diversity gain to combat signal fading and to achieve more capacity gain without increasing the bandwidth or transmit power. However, radio resource management (RRM) such as relay selection and resource allocation (RA) is important in such a multi-user, multirelay and multi-antenna environment to fully take advantage of multiple-input single-output (MISO)-OFDMA based user-relay assisted cellular networks. Thus, we propose a RA algorithm for these networks to reveal the benefits of the combination of userrelaying and multiple antennas technologies and compare the proposed scheme with existing schemes in terms of percentage of satisfied users and cell-edge users' data rate.
  • Conference Object
    Active Eye-Glasses With Local Dimming
    (Institute of Electrical and Electronics Engineers Inc., 2011) Özvural, Görkem; Gümüştekin, Şevket
    The sense of sight provides the most reliable information about the environment. Although the human eye has a wide dynamic range for brightness adaptation, direct exposure to relatively bright light sources wipes out the total visual perception. The most remarkable example of this situation is driving a car at night, while the other cars are coming from the opposite lane with headlights on. In this work, we have proposed and developed a set of LCD equipped active glasses to solve this light adaptation problem. First, the location of the light sources are determined using an on board camera which is assembled in front of the glasses. After processing image data, the locations of the bright light sources are darkened and the disturbing effect of intense light sources is reduced. © 2011 Chamber of Turkish Electric.
  • Article
    Citation - WoS: 9
    Citation - Scopus: 11
    Oxidation Behavior of C-And Au-Ion Biodegradable Polymers
    (Institute of Electrical and Electronics Engineers Inc., 2012) Sokullu Urkaç, Emel; Öztarhan, Ahmet; Tıhmınlıoğlu, Funda; Nikolaev, Alexey; Brown, Ian
    Biodegradable polymers are widely used in biomedical and tissue engineering applications due to their biocompatibility and hydrolysis properties in the body. However, their low surface energy and lack of functional groups to interact with the cellular environment have limited their applications for in vivo studies. Ion beam modification is a convenient method for improving the surface properties of polymeric materials for functional biomedical applications. In the work described here, vacuum arc metal ion implantation was used to modify the composition of the near-surface region of three kinds of polymerspoly(L-lactide), poly(D, L-lactide-co-glycolide), and poly(L-lactide/caprolactone)chosen as representative of biodegradable polymers. X-ray photoelectron spectroscopy analysis was used to characterize the chemical effects of these polymers after implantation with C and with Au, and the results were compared with untreated control samples. We find that oxidation behavior is brought about for certain implantation fluences, resulting in improved surface hydrophilicity. © 2011 IEEE.
  • Conference Object
    Citation - WoS: 2
    Citation - Scopus: 12
    A Review of Cloud Deployment Models for E-Learning Systems
    (Institute of Electrical and Electronics Engineers Inc., 2013) Leloğlu, Engin; Ayav, Tolga; Aslan, Burak Galip
    With the significant growth in the cloud-based systems, many industries give their attention to cloud computing solutions. E-learning is a promising application area since its typical requirements such as dynamically allocation of computation and storage resources, coincide well with cloud characteristics. This paper presents some possible cloud solutions in e-learning environments by emphasizing its pros and cons. It is of paramount importance to choose the most suitable cloud model for an e-learning application or an educational organization in terms of scalability, portability and security. We distinguish various deployment alternatives of cloud computing and discuss their benefits against typical e-learning requirements.
  • Conference Object
    Citation - WoS: 9
    Citation - Scopus: 13
    Design of a Haptic Device for Teleoperation and Virtual Reality Systems
    (Institute of Electrical and Electronics Engineers Inc., 2009) Dede, Mehmet İsmet Can; Selvi, Özgün; Bilgincan, Tunç; Kant, Yalkın
    Haptics technology has increased the precision and telepresence of the teleoperation and precision of the in-house robotic applications by force and surface information feedback. Force feedback is achieved through sending back the pressure and force information via a haptic device as the information is created or measured at the point of interest. In order to configure such a system, design, analysis and production processes of a haptic device, which is suitable for that specific application, becomes important. Today, haptic devices find use in assistive surgical robotics and most of the teleoperation systems. These devices are also extensively utilized in simulators to train medical and military personnel. The objective of this work is to design a haptic device with a new structure that has the potential to increase the precision of the robotic operation. Thus, literature is reviewed and possible robot manipulator designs are investigated to increase the precision in haptics applications. As a result of the investigations, conceptual designs are developed. Ultimately, final design is selected and produced after it is investigated in computer-aided- design (CAD) environment and its kinematic and structural analyses are carried out.
  • Conference Object
    Citation - Scopus: 1
    Implementation of Partial Synchronization of Different Chaotic Systems by Field Programmable Gate Array
    (Institute of Electrical and Electronics Engineers Inc., 2009) Eroğlu, Can; Savacı, Ferit Acar
    In this study, the synchronization of the master-slave systems has been achieved and implemented on Field Programmable Gate Array (FPGA). In this paper, the master system and the slave system have been chosen as Lorenz and Rossler systems, respectively. The feedback control rule has been derived by feedback linearization method. By feedback linearization, the coordinate transformation has been achieved then the control command for synchronization has been obtained. In order to implement designed synchronized system, Matlab Simulink design of the system has been translated to Xilinx System Generator design to generate Very-High-Speed Integrated Circuits Hardware Description Language (VHDL) code which is used to produce bitstream file. By Xilinx Integrated Software Environment (ISE) program, VHDL code is converted to bitstream file which has been embedded into FPGA by Field Upgradeable Systems Environment (FUSE). Finally, the designed synchronized system has been observed on the HP 54540C oscilloscope.
  • Conference Object
    Citation - WoS: 7
    Citation - Scopus: 12
    Time Synchronization Algorithms Based on Timing-Sync Protocol in Wireless Sensor Networks
    (Institute of Electrical and Electronics Engineers Inc., 2008) Kulaklı, Ali Burak; Erciyeş, Kayhan
    Wireless Sensor Networks(WSN) are large scale networks of sensors running on wireless environment. For an application running on a WSN, gathered data by the sensors are time critical in most of the cases. However, almost all the nodes suffer from a problem named clock drift. This problem causes clock difference among nodes as time goes because the processors do not run exactly at the same speed. There are many proposed solutions to remedy this problem. TPSN (Timing-sync Protocol for Sensor Networks) is one of the effective protocols proposed to synchronize sensor networks. In this paper, we propose enhancements over TPSN to synchronize nodes in a wireless sensor network more effectively with a lower message complexity and higher precision.