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Yayın Positive solutions for a sum-type singular fractional integro-differential equation with m-point boundary conditions(Politechnica University of Bucharest, 2017) Aydoğan, Seher Melike; Nazemi, Sayyedeh Zahra; Rezapour, ShahramWe study the existence and uniqueness of positive solutions for a sum-type singular fractional integro-differential equation with m-point boundary condition. Also, we provide an example to illustrate our main result.Yayın EEG signal compression based on classified signature and envelope vector sets(Wiley, 2009-03) Gürkan, Hakan; Güz, Ümit; Yarman, Bekir Sıddık BinboğaIn this paper, a novel method to compress electroencephalogram (EEG) signal is proposed. The proposed method is based on the generation process of the classified signature and envelope vector sets (CSEVS), which employs an effective k-means clustering algorithm. It is assumed that both the transmitter and the receiver units have the same CSEVS. In this work, on a frame basis, EEG signals are modeled by multiplying only three factors called as classified signature vector, classified envelope vector, and gain coefficient (GC), respectively. In other words, every frame of an EEG signal is represented by two indices R and K of CSEVS and the GC. EEG signals are reconstructed frame by frame using these numbers in the receiver unit by employing the CSEVS. The proposed method is evaluated by using some evaluation metrics that are commonly used in this area such as root-mean-square error, percentage root-mean-square difference, and measuring with visual inspection. The performance of the proposed method is also compared with the other methods. It is observed that the proposed method achieves high compression ratios with low-level reconstruction error while preserving diagnostic information in the reconstructed EEG signal.Yayın Reductions of topologically massive gravity I: Hamiltonian analysis of second order degenerate Lagrangians(Amer Inst Physics, 2018-01) Uçgun, Filiz Çağatay; Esen, Oğul; Gümral, HasanWe present Skinner-Rusk and Hamiltonian formalisms of second order degenerate Clement and Sarioglu-Tekin Lagrangians. The Dirac-Bergmann constraint algorithm is employed to obtain Hamiltonian realizations of Lagrangian theories. The Gotay-Nester-Hinds algorithm is used to investigate Skinner-Rusk formalisms of these systems.Yayın Synthesis and liquid crystalline behavior of random copolymer of poly(ethylene oxide) macromonomer and liquid crystalline monomer by the photon transmission technique(Taylor & Francis Inc, 2005-12) Yıldız, Sevtap; Yılmaz, Faruk; Özbek, Haluk; Pekcan, Mehmet Önder; Ito, Koichi; Yağcı, YusufRandom copolymers of poly(ethylene oxide) macromonomer with p-vinylbenzyl end-functional group (PEOVB) and liquid crystalline monomer, namely 6-(4-cyanobiphenyl-4'-oxy)hexyl acrylate (COA), were prepared by conventional free radical polymerization. A living anionic polymerization technique was employed for the synthesis of PEO macromonomers bearing p-vinylbenzyl moiety at one end. The photon transmission method was also applied to study the phase transitions of COA monomer and its random copolymer with PEO. It was found that, for both samples, the nematic-smectic A transition is continuous, but the critical fluctuation regions do not allow to obtain 3D XY values. Instead, we have obtained the values close to mean field regime. Scaling of thermal hystersis for random copolymer sample near the nematic-isotropic transition was studied as well. Thermal hysteresis loops were produced under linearly varying temperature. It was shown that the areas of the hysteresis loops scale with the temperature scanning rate with an exponent being equal to 0.614 which is in good agreement with the field-theoretical value.Yayın The moderating role of environmental munificence on innovativeness in B2B markets(Emerald Group Publishing Limited, 2019-09-30) Gül, Mısra ÇağlaPurpose: The purpose of this paper is to understand the relationship between two business orientations, namely, entrepreneurial orientation and market orientation, and innovativeness taking into account the moderating influence of environmental munificence. Design/methodology/approach: This is a multiple respondent quantitative study. A total of 312 marketing managers middle level and above from 79 firms participated in the survey. Multiple regression and hierarchical multiple regression was the method of choice for data analysis. Findings: Findings indicate that environmental munificence moderates the entrepreneurial orientation – innovativeness relationship. Findings reveal that even though a significant impact of entrepreneurial orientation is not present on innovativeness, this insignificance may be due to environmental munificence. Market orientation has a direct positive impact on innovativeness, and environmental munificence negatively moderates this relationship suggesting that when the environment is less munificent, the market orientation – innovation link becomes stronger. Practical implications: Managers should be aware that the more munificent an environment becomes, having an entrepreneurial orientation will be more important for innovativeness. In addition, results of this study suggest that being market oriented more strongly impacts a firm’s ability to innovate in non-munificent environments where growth opportunities are undesirable. Originality/value: This study is unique in that it is a multi-respondent study with respondents from different layers of each participating organization, incorporating the moderating impact of the business environment’s munificence on business orientations–innovativeness relationship.Yayın The sectoral sweeper scheme for wireless sensor networks: Adaptive antenna array based sensor node management and location estimation(Kluwer Academic Publishers-Plenum Publishers, 2006-12) Erdoğan, Ayhan; Coşkun, Vedat; Kavak, AdnanWe introduce a novel sensor node management and location estimation method referred as sectoral sweeper (SS) scheme that uses an adaptive antenna array (AAA) at a central node in wireless sensor networks (WSNs). With the SS scheme, the central node can activate or deactivate the nodes in a desired region which is specified by beam direction and beam width of the transmit beam and also by minimum and maximum thresholds (R (min) and R (max)) for the received signal strength indicator (RSSI) of signals received by the nodes. In order to perform a specified task that is associated with a Task_id, two different beams are transmitted, which are task region beam and routing region beam to switch the nodes into active or routing modes. Since our scheme does not require any additional software or hardware for node management and location estimation in sensor nodes, the deficiencies of tiny sensors are effectively eliminated. The proposed scheme is shown to reduce the number of sensing nodes and the amount of data traffic in the network, thus leading to considerable savings in energy consumption and prolonged sensor lifetime.Yayın The state of property development in Turkey: facts and comparisons(Cambridge University Press, 2016-09-01) Demiralp, Seda; Demiralp, Selva; Gümüş, İnciIn this article, we investigate economic and political developments in Turkey's construction sector over the last decade and consider their implications. We find that during the first term of the government of the Justice and Development Party (Adalet ve Kalklnma Partisi, AKP), thanks to administrative and economic incentives, both private and public construction rose considerably. Despite the construction sector's contribution to growth, there is also evidence of a transfer from the industrial sector toward the construction sector, which led to significant decline in the trend growth of the industrial sector in the era prior to 2006. Such evidence disappears in the post-crisis period, when the growth of private construction slows. However, overcentralization, clientelism, an absence of transparency, and limitations on citizen participation in urban planning remain as problems that need to be addressed through urban reform.Yayın Maximum likelihood blind channel estimation for space-time coding systems(Hindawi Publishing Corporation, 2002-05) Çırpan, Hakan Ali; Panayırcı, Erdal; Çekli, ErdinçSophisticated signal processing techniques have to be developed for capacity enhancement of future wireless communication systems, In recent years, space-time coding is proposed to provide significant capacity gains over the traditional communication systems in fading wireless channels. Space-time codes are obtained by combining channel coding, modulation, transmit diversity, and optional receive diversity in order to provide diversity at the receiver and coding gain without sacrificing the bandwidth. In this paper, we consider the problem of blind estimation of space-time coded signals along with the channel parameters. Both conditional and unconditional maximum likelihood approaches are developed and iterative solutions are proposed. The conditional maximum likelihood algorithm is based on iterative least squares with projection whereas the unconditional maximum likelihood approach is developed by means of finite state Markov process modelling. The performance analysis issues of the proposed methods are studied. Finally, some simulation results are presented.Yayın Comment on "Modified Baptista type chaotic cryptosystem via matrix secret key" [Phys. Lett. A 372 (2008) 5427](Elsevier Science BV, 2009-09-07) Rhouma, Rhouma; Solak, Ercan; Arroyo, David; Li, Shujun; Alvarez, Gonzalo; Belghith, Safya MdimeghIn this comment, we analyze a recently proposed Baptista-like cryptosystem and show that it is not invertible. Others weaknesses are also reported. A modified version of this cryptosystem is proposed to show how to overcome the non-invertibility.Yayın Development of externalizing behaviors in the context of family and non-family relationships(Springer New York, 2016-02-04) Akçinar Yayla, Berna; Baydar, NazlıA longitudinal model was presented, that included reciprocal associations between physically harsh parenting by the mother, child externalizing problems, and support from the father, the extended family, and the neighbors. This transactional process was estimated for the years preceding school entry. The data were from a 4-years longitudinal and nationally representative study of 1009 children and their mothers in Turkey. The results indicated that concurrently, physically harsh parenting and child externalizing problems were strongly associated. Controlling for their within domain stability and cross-domain concurrent correlation, changes in harsh parenting and changes in child externalizing behaviors had significant reciprocal effects in early childhood, although these effects were small. These reciprocal effects were smaller for observer reported harsh parenting than maternal reports. There was a role of the mesosystem in this developmental process. Increases in the support from the father, and the extended family and the neighbors predicted declines in the child externalizing behaviors subsequently. Reciprocally, high child externalizing and maternal physically harsh parenting predicted subsequent declines in the support from these sources. These results were consistent with the hypotheses that negative mother–child relationships could spill over to the other relationships of the mothers, and that positive and supportive relationships of the mother could constitute positive role models for the child.
