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Publication Metadata only A blind fractionally spaced equalization algorithm with global convergence(IEEE, 2007) Department of Electrical and Electronics Engineering; Erdoğan, Alper Tunga; Faculty Member; Department of Electrical and Electronics Engineering; College of Engineering; 41624In this article we present a fractionally spaced extension of the SubGradient based Blind equalization Algorithm (SGBA). The basic features of the proposed algorithm are the non-linear constraint on the search vector and the selection of the weighting and step size applied to the search vector. It is proven that the algorithm is globally convergent to a perfect equalization point under the well known equalizability conditions for the fractionally spaced setting. The simulation results provided at the end of the article illustrates the relative merit of the proposed algorithm in comparison to the state of the art algorithms.Publication Metadata only Adaptive algorithm for the blind separation of sources with finite support(IEEE, 2008) Department of Electrical and Electronics Engineering; Erdoğan, Alper Tunga; Faculty Member; Department of Electrical and Electronics Engineering; College of Engineering; 41624A new blind separation algorithm which exploits only the finite support property and the independence of the sources is proposed. The approach is based on the minimization of magnitude peaks of some affine mapping outputs. It is proven that the perfect separators are the only global minima of the corresponding cost function. The proposed method leads to the construction of a simple adaptive algorithm for the separation of sources. A simulation example is provided to illustrate the algorithm's performance. copyright by EURASIP.Publication Metadata only An extended family of bounded component analysis algorithms(IEEE Computer Society, 2015) Department of Electrical and Electronics Engineering; N/A; Erdoğan, Alper Tunga; İnan, Hüseyin Atahan; Faculty Member; Master Student; Department of Electrical and Electronics Engineering; College of Engineering; Graduate School of Sciences and Engineering; 41624; N/ABounded Component Analysis (BCA) is a recent concept proposed as an alternative method for Blind Source Separation problem. BCA enables the separation of dependent as well as independent sources from their mixtures under the practical assumption on source boundedness. This article extends the optimization setting of a recent BCA approach which can be used to produce a variety of BCA algorithms. The article also provides examples of objective functions and the corresponding iterative algorithms. The numerical examples illustrate the advantages of proposed BCA examples regarding the correlated source separation capability over the state of the art ICA based approaches. 1 © 2014 IEEE.Publication Metadata only Analysis of engagement and user experience with a laughter responsive social robot(Isca-int Speech Communication assoc, 2017) N/A; N/A; Department of Computer Engineering; Department of Computer Engineering; Department of Computer Engineering; Türker, Bekir Berker; Buçinca, Zana; Erzin, Engin; Yemez, Yücel; Sezgin, Tevfik Metin; PhD Student; Master Student; Faculty Member; Faculty Member; Faculty Member; Department of Computer Engineering; Graduate School of Sciences and Engineering; Graduate School of Sciences and Engineering; College of Engineering; College of Engineering; College of Engineering; N/A; N/A; 34503; 107907; 18632We explore the effect of laughter perception and response in terms of engagement in human-robot interaction. We designed two distinct experiments in which the robot has two modes: laughter responsive and laughter non-responsive. in responsive mode, the robot detects laughter using a multimodal real-time laughter detection module and invokes laughter as a backchannel to users accordingly. in non-responsive mode, robot has no utilization of detection, thus provides no feedback. in the experimental design, we use a straightforward question-answer based interaction scenario using a back-projected robot head. We evaluate the interactions with objective and subjective measurements of engagement and user experience.Publication Metadata only Audio-visual prediction of head-nod and turn-taking events in dyadic interactions(Isca-int Speech Communication assoc, 2018) N/A; Department of Computer Engineering; Department of Computer Engineering; Department of Computer Engineering; Türker, Bekir Berker; Erzin, Engin; Yemez, Yücel; Sezgin, Tevfik Metin; PhD Student; Faculty Member; Faculty Member; Faculty Member; Department of Computer Engineering; Graduate School of Sciences and Engineering; College of Engineering; College of Engineering; College of Engineering; N/A; 34503; 107907; 18632Head-nods and turn-taking both significantly contribute conversational dynamics in dyadic interactions. Timely prediction and use of these events is quite valuable for dialog management systems in human-robot interaction. in this study, we present an audio-visual prediction framework for the head-nod and turn taking events that can also be utilized in real-time systems. Prediction systems based on Support vector Machines (SVM) and Long Short-Term Memory Recurrent Neural Networks (LSTM-RNN) are trained on human-human conversational data. Unimodal and multi-modal classification performances of head-nod and turn-taking events are reported over the IEMOCaP dataset.Publication Metadata only Batch fabrication of self-assembled nickel-iron nanowires by electrodeposition(IEEE, 2006) N/A; Department of Electrical and Electronics Engineering; Department of Mechanical Engineering; Şardan, Özlem; Yalçınkaya, Arda Deniz; Alaca, Burhanettin Erdem; Master Student; Researcher; Faculty Member; Department of Electrical and Electronics Engineering; Department of Mechanical Engineering; Graduate School of Sciences and Engineering; College of Engineering; College of Engineering; N/A; 144523; 115108Lack of batch-compatible fabrication techniques can be considered as the most important challenge in the integration of nanostructures with microelectromechanical systems (MEMS). a solution to the micro-nano integration problem is offered by introducing a batch-compatible nanowire fabrication technique based on basic lithographic techniques and guided self-assembly. the basic principle is obtaining cracks at predetermined locations in a sacrificial SiO2 layer on Si and filling these cracks with a suitable metal by electrodeposition. the technique is demonstrated by using Nickel-Iron as the deposition material and verifying the magnetic behavior of resulting nanowires.Publication Metadata only BindMe: a thread binding library with advanced mapping algorithms(Wiley, 2018) N/A; Department of Computer Engineering; Department of Computer Engineering; Soomro, Pirah Noor; Sasongko, Muhammad Aditya; Erten, Didem Unat; PhD Student; Researcher; Faculty Member; Department of Computer Engineering; Graduate School of Sciences and Engineering; College of Engineering; College of Engineering; N/A; N/A; 219274Binding parallel tasks to cores according to a placement policy is one of the key aspects to achieve good performance in multicore machines because it can reduce on-chip communication among parallel threads. Binding also prevents operating system from migrating threads, which improves data locality. However, there is no single mapping policy that works best among all different kinds of applications and platforms because each machine has a different topology and each application exhibits different communication pattern. Determining the best policy for a given application and machine requires extra programming effort. To relieve the programmer from that burden, we introduce BindMe, A thread binding library that assists programmer to bind threads to underlying hardware. BindMe incorporates state-of-the-art mapping algorithms, which use communication pattern in an application to formulate an efficient task placement policy. We also introduce ChoiceMap, A communication aware mapping algorithm that respects mutual priorities of parallel tasks and performs a fair mapping by reducing communication volume among cores. We have tested BindMe and ChoiceMap with various applications from NaS parallel benchmark and Rodinia bechmark. Our results show that choosing a mapping policy that best suits the application behavior can increase its performance and no single policy gives the best performance across different applications.Publication Metadata only Comb- actuated resonant torsional scanner for microdisplays(IEEE, 2009) Department of Electrical and Electronics Engineering; N/A; Department of Electrical and Electronics Engineering; Ürey, Hakan; Gökçe, Sertan Kutal; Holmstrom, Sven; Arslan, Aslıhan; Faculty Member; Master Student; Researcher; Master Student; Department of Electrical and Electronics Engineering; College of Engineering; Graduate School of Sciences and Engineering; College of Engineering; Graduate School of Sciences and Engineering; 8579; N/A; N/A; N/AA comb-actuated 1D torsional MEMS scanner is developed for high resolution projection display systems using mechanical coupling principle. 64° TOSA (total optical scan angle) is achieved at 22.1 kHz with 170 V peak-to-peak excitation voltages.Publication Metadata only Comparison of phoneme and viseme based acoustic units for speech driven realistic lip animation(IEEE, 2007) Bozkurt, Elif; Erdem, Çiǧdem Eroǧlu; Erdem, Tanju; Özkan, Mehmet; Department of Computer Engineering; Erzin, Engin; Faculty Member; Department of Computer Engineering; College of Engineering; 34503Natural looking lip animation, synchronized with incoming speech, is essential for realistic character animation. In this work, we evaluate the performance of phone and viseme based acoustic units, with and without context information, for generating realistic lip synchronization using HMM based recognition systems. We conclude via objective evaluations that utilization of viseme based units with context information outperforms the other methods./ Öz: Konuşma ile senkronize ve doğal görünen dudak hareketlerinin üretilmesi, gerçekçi karakter animasyonu için önemli bir problemdir. Bu çalışmada, gerçekçi dudak hareketleri üretebilmek için Saklı Markov Modeli (SMM) kullanarak, fonem ve vizem temelli akustik birimlerin başarımlarını karşılaştırıyoruz. Nesnel değerlendirmeler sonucunda, komşuluk bilgisini kullanan vizem temelli akustik birimlerin diğer metodlardan daha üstün olduğunu gösteriyoruz.Publication Metadata only Competitive randomized nonlinear prediction under additive noise(IEEE-Inst Electrical Electronics Engineers Inc, 2010) N/A; Department of Electrical and Electronics Engineering; Yılmaz, Yasin; Kozat, Süleyman Serdar; Master Student; Faculty Member; Department of Electrical and Electronics Engineering; Graduate School of Sciences and Engineering; College of Engineering; N/A; 177972We consider sequential nonlinear prediction of a bounded, real-valued and deterministic signal from its noise-corrupted past samples in a competitive algorithm framework. We introduce a randomized algorithm based on context-trees [1]. The introduced algorithm asymptotically achieves the performance of the best piecewise affine model that can both select the best partition of the past observations space (from a doubly exponential number of possible partitions) and the affine model parameters based on the desired clean signal in hindsight. Although the performance measure including the loss function is defined with respect to the noise-free clean signal, the clean signal, its past samples or prediction errors are not available for training or constructing predictions. We demonstrate the performance of the introduced algorithm when applied to certain chaotic signals.