Elektronik ve Haberleşme Mühendisliği Bölümü Yayın Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/260
Browse
42 results
Search Results
Article Citation - WoS: 5Citation - Scopus: 9Strategy Creation, Decomposition and Distribution in Particle Navigation(Elsevier Science inc, 2007) Leblebicioglu, Kemal; Beldek, UlasStrategy planning is crucial to control a group to achieve a number of tasks in a closed area full of obstacles. In this study, genetic programming has been used to evolve rule-based hierarchical structures to move the particles in a grid region to accomplish navigation tasks. Communications operations such as receiving and sending commands between particles are also provided to develop improved strategies. In order to produce more capable strategies, a task decomposition procedure is proposed. In addition, a conflict module is constructed to handle the challenging situations and conflicts such as blockage of a particle's pathway to destination by other particles. (C) 2006 Elsevier Inc. All rights reserved.Editorial Citation - WoS: 5Citation - Scopus: 5Comments on "on the Modified Theory of Physical Optics(Ieee-inst Electrical Electronics Engineers inc, 2014) Umul, Yusuf Z.Article Citation - WoS: 3Citation - Scopus: 3Dissociative Chemisorption of an H2 (V,j) Molecule on Rigid Ni (100) Surface: Dependence on Surface Topologies and Initial Rovibrational States of the Molecules(Iop Publishing Ltd, 2005) Evecen, M; Böyükata, M; Çivi, M; Güvenç, ZBThe H-2(v,j)+Ni(100) collision system has been studied to understand the effects of the surface sites and initial rovibrational states of the molecule on molecule-surface interactions, by a quasiclassical molecular dynamic simulation method. Dissociative adsorption of an H-2 molecule on the rigid Ni(100) surface is investigated at topologically different three sites of the surface. Interaction between the molecule and Ni surface was described by a London-Eyring Polani-Sato (LEPS) potential. Dissociative chemisorption probabilities of the H-2(v, j) molecule on various sites of the surface are presented as a function of the translation energies between 0.001-1.0eV. The probabilities obtained at each collision site have unique behaviour. At lower collision energies, indirect processes enhance the reactivity, effects of the rotational excitations and impact sites on the reactivity are more pronounced. The results are compared with the available studies, The physical mechanisms underlying the results and quantum effects are discussed.Article Citation - WoS: 13Dft Study of Al Doped Cage B12hn Clusters(Pergamon-elsevier Science Ltd, 2011) Boyukata, Mustafa; Guvenc, Ziya B.Density Functional Theory (DFT) with B3LYP/6-311++g** level has been performed to investigate the electronic structures of cage B12Hn for up to n <= 12 and AlB12Hn for up to n <= 13. Moreover, the computations has been extended to the charged clusters of [B12H12](q), [AlB12H12](q) and [AlB12H13](q) where (q = +/- 1 and +/- 2). Their energetics are calculated and structural analysis have been carried out. Cage form of the B-12 remains stable against to hydrogen adsorptions. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.Article Citation - WoS: 48Citation - Scopus: 50High-Throughput Screening of Large Volumes of Whole Blood Using Structured Illumination and Fluorescent On-Chip Imaging(Royal Soc Chemistry, 2012) Arpali, Serap Altay; Arpali, Caglar; Coskun, Ahmet F.; Chiang, Hsin-Hao; Ozcan, AydoganUndiluted blood samples are difficult to image in large volumes since blood constitutes a highly absorbing and scattering medium. As a result of this limitation, optical imaging of rare cells (e.g., circulating tumour cells) within unprocessed whole blood remains a challenge, demanding the use of special microfluidic technologies. Here we demonstrate a new fluorescent on-chip imaging modality that can rapidly screen large volumes of absorbing and scattering media, such as undiluted whole blood samples, for detection of fluorescent micro-objects at low concentrations (for example <= 50-100 particles/mL). In this high-throughput imaging modality, a large area microfluidic device (e.g., 7-18 cm(2)), which contains for example similar to 0.3-0.7 mL of undiluted whole blood sample, is directly positioned onto a wide-field opto-electronic sensor-array such that the fluorescent emission within the microchannel can be detected without the use of any imaging lenses. This microfluidic device is then illuminated and laterally scanned with an array of Gaussian excitation spots, which is generated through a spatial light modulator. For each scanning position of this excitation array, a lensfree fluorescent image of the blood sample is captured using the opto-electronic sensor-array, resulting in a sequence of images (e.g., 144 lensfree frames captured in similar to 36 s) for the same sample chip. Digitally merging these lensfree fluorescent images based on a maximum intensity projection (MIP) algorithm enabled us to significantly boost the signal-to-noise ratio (SNR) and contrast of the fluorescent micro-objects within whole blood, which normally remain undetected (i.e., hidden) using conventional uniform excitation schemes, involving plane wave illumination. This high-throughput on-chip imaging platform based on structured excitation could be useful for rare cell research by enabling rapid screening of large volume microfluidic devices that process whole blood and other optically dense media.Article Citation - WoS: 8Citation - Scopus: 10Spectrum-Aware and Energy-Adaptive Reliable Transport for Internet of Sensing Things(Ieee-inst Electrical Electronics Engineers inc, 2018) Bicen, A. Ozan; Ergul, Ozgur; Akan, Ozgur B.; Ozan Bicen, A.Wireless sensors equipped with cognitive radio, i.e., cognitive radio sensor networks (CRSN), can access the spectrum in an opportunistic manner and coexist with licensed users to mitigate the crowded spectrum problem and provide ubiquitous remote event monitoring and tracking for cyber-physical systems. In this paper, a novel transport layer protocol for CRSN, spectrum-aware energy-adaptive reliable transport protocol is presented to enable energy-adaptive collaborative event sensing in spectrum-scarce cyber-physical systems. To the best of our knowledge, this is the first attempt to specifically devise a reliable event transport scheme for CRSN.Article Citation - WoS: 1Citation - Scopus: 1Mode Coupling in Vortex Beams(Elsevier Sci Ltd, 2018) Eyyuboglu, Halil T.We examine the mode coupling in vortex beams. Mode coupling also known as the crosstalk takes place due to turbulent characteristics of the atmospheric communication medium. This way, the transmitted intrinsic mode of the vortex beam leaks power to other extrinsic modes, thus preventing the correct detection of the transmitted symbol which is usually encoded into the mode index or the orbital angular momentum state of the vortex beam. Here we investigate the normalized power mode coupling ratios of several types of vortex beams, namely, Gaussian vortex beam, Bessel Gaussian beam, hypergeometric Gaussian beam and Laguerre Gaussian beam. It is found that smaller mode numbers lead to less mode coupling. The same is partially observed for increasing source sizes. Comparing the vortex beams amongst themselves, it is seen that hypergeometric Gaussian beam is the one retaining the most power in intrinsic mode during propagation, but only at lowest mode index of unity. At higher mode indices this advantage passes over to the Gaussian vortex beam. (C) 2017 Elsevier Ltd. All rights reserved.Article Citation - WoS: 8Citation - Scopus: 12Implementation and Characterization of an Absorption Filter for On-Chip Fluorescent Imaging(Elsevier Science Sa, 2017) Arpali, Caglar; Arpali, Serap Altay; Yildirim, EnderHere we present fabrication and characterization of an absorption filter with superior roll-on properties and precisely tunable cut-off wavelengths for fluorescent imaging applications in lab-on-a-chip systems. The filters were fabricated by spinning dye doped photopolymer (Orasol Yellow in Norland Optical Adhesive 60) on glass substrates. The fabrication technique allowed us to precisely tune the cut-off wavelength of the filters. We showed that filters with different cut-off in the range of 386 nm-504 nm could be obtained simply by controlling the settling time before spinning. The filters exhibited a steep roll-on from stopband to passband at the cut-off. Transmission in the stopband was observed to be maximum 3% while it was almost constant at 100% in the passband within the range of 220 nm-620 nm. On-chip use of the filters was also demonstrated for imaging particular fluorescent beads. (C) 2016 Elsevier B.V. All rights reserved.Article Citation - WoS: 10Citation - Scopus: 10Scattering of Evanescent Plane Waves by a Black Wedge at the Interface Between Isorefractive Media(Ieee-inst Electrical Electronics Engineers inc, 2016) Basdemir, Husnu DenizThe scattering of evanescent plane waves by a black wedge located at the interface of two isorefractive media is investigated in order to extend the results for the perfectly conducting half-plane case reported by Uslenghi (2013). The geometrical optics, in addition to the diffracted and scattered fields, are analyzed numerically. The effect of the isorefractive media on the diffracted field and the effect of the evanescent plane-wave excitation on the scattered field are also examined.Article Citation - WoS: 12Citation - Scopus: 12Scattering of Waves by a Perfectly Conducting Wedge Residing at the Interface Between Two Isorefractive Media(Ieee-inst Electrical Electronics Engineers inc, 2016) Basdemir, Husnu DenizScattered field by a wedge that is surrounded by isorefractive media is analyzed. A series-based method is introduced and applied to the wedge problem with soft boundary condition. The fields are examined numerically. The numerical results show that the proposed method is suitable for analysis of these kinds of problems.