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Yayın Analysis of self noise in a clock recovery systems with a high-order nonlinearity(IEEE, 1998) Panayırcı, ErdalThis paper presents a new technique to compute efficiently the I and Q spectra, and the I - Q cross-spectrum of the self noise appearing at the output of the zero-memory, high order nonlinear device employed in a clock recovery system. It is known that these spectra play an important role in the phase jitter performance of the clock regenerator. The results are very general and applicable to many cases of practical interest. A numerical example provided at the end of the paper shows that the new approach yields very accurate results and is much faster that the usual computer simulation method.Yayın Power control in the cognitive cooperative multiple access channel(IEEE, 2012) Kaya, Onur; İşleyen, MuratWe extend several encoding and decoding techniques from cooperative communications framework, to a cognitive radio system consisting of a primary user (PU) and a secondary user (SU), sending their messages to a common receiver. Assuming that the transmitters and the receiver have full channel state information (CSI) collected and distributed by the common receiver, and that the SU knows the PU's codebook, the cooperation is obtained by block Markov superposition coding, and backwards decoding, which yield a causal overlay scenario. We formulate two rate optimization problems with the aim of, (i) maximizing the sum rate of the system, and (ii) maximizing the rate of the secondary user. We obtain the optimal power allocations for both cases, and the resulting rate regions. The power controlled cooperation turns out to be especially useful when maximizing the sum rate of the system, as it gives the PU significant rate rewards for allowing the cognitive transmitter to access its resources.Yayın Lossy matched and feedback broadband power amplifiers(CRC Press Taylor & Francis Group, 2016) Grebennikov, Andrei; Kumar, Narendra; Yarman, Bekir Sıddık Binboğa[No abstract available]Yayın Sound and the healthy city(Bellwether Publishing, 2021) Radicchi, Antonella; Çevikayak Yelmi, Pınar; Chung, Andy; Jordan, Pamela; Stewart, Sharon; Tsaligopoulos, Aggelos; McCunn, Lindsay; Grant, MarcusAt an international level it is recognised that urban noise has serious and negative public health impacts. This leading editorial and the special issue it accompanies seeks to broaden this agenda. An important goal for Cities & Health is to give ear to new urban health topics, methods and collaborations. In doing so this paper presents the topic of urban sound and health from several unique angles. At its core, we deliberately move the focus beyond noise levels, as measured by decibels, and harm to health through the stress of relentless background noise. Instead, we focus on the concept of soundscape, a more qualitatively nuanced research subject of enquiry. The paper serves as an introduction to soundscape and health from several distinct disciplinary positions and lays a good intellectual foundation for the twenty-two papers published in this special issue. We hope that through a soundscape approach we can encourage fresh thinking about urban sound, including how people perceive and relate to their sonic environments, and show how sound can contribute to health. We believe that this approach can provide a collaborative platform for sound artists, sound technologists, urbanists and local people to work together with public health and create healthier urban environments.Yayın Distributed amplifiers(CRC Press-Taylor & Francis Group, 2016) Grebennikov, Andrei; Kumar, Narendra; Yarman, Bekir Sıddık Binboğa[No abstract available]Yayın Two-port network parameters(CRC Press Taylor & Francis Group, 2016) Grebennikov, Andrei; Kumar, Narendra; Yarman, Bekir Sıddık Binboğa[No abstract available]Yayın On the performance of trellis coded M-PSK systems over Rician fading channels with phase jitter(Assoc Elettrotecnica Ed Elettronica Italiana, 2001-02) Uysal, Murat; Aygölü, Hasan Ümit; Panayırcı, ErdalIn this paper, the performance of trellis coded M-PSK systems is investigated operating over Rician fading channels with phase jitter. Thus the results reflect not only the degradation due to the effect of fading on the amplitude of the received signal, but also the impairment caused by the noisy carrier reference, which is usually neglected by the assumption of perfect phase tracking at the receiver. Analytical upper bounds on pairwise error probability for Rician fading with phase jitter are derived using Chernoff bounding technique in both cases where channel state information is available or not. The bit error probability performances are evaluated based on the modified transfer function approach. The numerical examples clearly demonstrate the error performance degradation due to both amplitude fading and phase noise process.Yayın Grammar or crammer? the role of morphology in distinguishing orthographically similar but semantically unrelated words(Institute of Electrical and Electronics Engineers Inc., 2025) Ercan, Gökhan; Yıldız, Olcay TanerWe show that n-gram-based distributional models fail to distinguish unrelated words due to the noise in semantic spaces. This issue remains hidden in conventional benchmarks but becomes more pronounced when orthographic similarity is high. To highlight this problem, we introduce OSimUnr, a dataset of nearly one million English and Turkish word-pairs that are orthographically similar but semantically unrelated (e.g., grammar - crammer). These pairs are generated through a graph-based WordNet approach and morphological resources. We define two evaluation tasks - unrelatedness identification and relatedness classification - to test semantic models. Our experiments reveal that FastText, with default n-gram segmentation, performs poorly (below 5% accuracy) in identifying unrelated words. However, morphological segmentation overcomes this issue, boosting accuracy to 68% (English) and 71% (Turkish) without compromising performance on standard benchmarks (RareWords, MTurk771, MEN, AnlamVer). Furthermore, our results suggest that even state-of-the-art LLMs, including Llama 3.3 and GPT-4o-mini, may exhibit noise in their semantic spaces, particularly in highly synthetic languages such as Turkish. To ensure dataset quality, we leverage WordNet, MorphoLex, and NLTK, covering fully derivational morphology supporting atomic roots (e.g., '-co_here+ance+y' for 'coherency'), with 405 affixes in Turkish and 467 in English.
