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Yayın Relative effects of marketing effectiveness dimensions on firm performance: An empirical analysis with a multi-industry sample(Bogazici Universitesi, 2009) Gül, Mısra ÇağlaThe aim of this study is to understand the influence of marketing operational efficiency and marketing system effectiveness on firm performance dimensions. Marketing operational efficiency and marketing system effectiveness are two dimensions of marketing effectiveness derived as a result of the exploratory factor analysis performed on the data. Firm performance dimensions used in the study are overall performance, ROI, percentage of new product sales, change in market share, and sales growth, all measured relative to competitors. Multiple respondent firm level data are collected through a survey of 74 firms operating in a variety of industries, resulting in 296 individual surveys. Findings indicate that marketing operational efficiency, a set of short-term, operational dimensions, positively influences all of the firm performance dimensions. On the other hand, marketing system effectiveness, measuring longer-term, strategic factors, does not have such an impact.Yayın Head-on collision of the solitary waves in fluid-filled elastic tubes(Işık University Press, 2018-04-12) Özden, Ali Erinç; Demiray, HilmiIn the present work, by employing the field equations given in [15] and the extended PLK method derived in [9], we have studied the head-on collision of solitary waves in arteries. Introducing a set of stretched coordinates which include some unknown functions characterizing the higher order dispersive effects and the trajectory functions to be determined from the removal of possible secularities that might occur in the solution. Expanding these unknown functions and the field variables into power series of the smallness parameter epsilon and introducing the resulting expansions into the field equations we obtained the sets of partial differential equations. By solving these differential equations and imposing the requirements for the removal of possible secularities we obtained the speed correction terms and the trajectory functions. The results of our calculation show that both the evolution equations and the phase shifts resulting from the head-on collision of solitary waves are quite different from those of Xue [15], who employed the incorrect formulation of Su and Mirie [4]. As opposed to the result of previous works on the same subject, in the present work the phase shifts depend on the amplitudes of both colliding waves.Yayın An analysis of stability of a class of neutral-type neural networks with discrete time delays(Hindawi Publishing Corporation, 2013) Orman, Zeynep; Arik, SabriThe problem of existence, uniqueness, and global asymptotic stability is considered for the class of neutral-type neural network model with discrete time delays. By employing a suitable Lyapunov functional and using the homeomorphism mapping theorem, we derive some new delay-independent sufficient conditions for the existence, uniqueness, and global asymptotic stability of the equilibrium point for this class of neutral-type systems. The obtained conditions basically establish some norm and matrix inequalities involving the network parameters of the neural system. The main advantage of the proposed results is that they can be expressed in terms of network parameters only. Some comparative examples are also given to compare our results with the previous corresponding results and demonstrate the effectiveness of the results presented.Yayın Behavior of quantum fisher information of bell pairs under decoherence channels(Polish Acad Sciences Inst Physics, 2014-02) Özaydın, Fatih; Altıntaş, Azmi Ali; Buğu, Sinan; Yeşilyurt, CanQuantum Fisher information has recently been an essential tool for analyzing the phase sensitivity of the quantum states in various quantum tasks, requiring high precision, such as quantum clock synchronization, positioning and many applications which include quantum interferometers. Due to the interactions with the environment, all quantum systems are subject to various decoherence effects. Therefore the research on quantum Fisher information under decoherence has been recently attracting more attention. In this work, analyzing the quantum Fisher information, we study the phase sensitivity of bipartite quantum correlations, in particular four Bell pairs amplitude damping channels. For a specific Bell state we arrive at similar results of Greenberger-Horne-Zeilinger (GHZ) states (as expected). For the other three Bell states, we present our results which point the interesting behavior of quantum Fisher information with respect to the decoherence rate. We also find the regions where the quantum Fisher information exhibits discontinuities.Yayın On progressive wave solution for non-planar KDV equation in a plasma with q-nonextensive electrons and two oppositely charged ions(Işık University Press, 2020) Demiray, Hilmi; El-Zahar, Essam Roshdy; Shan, Shaukat AliIn this paper, the ion-acoustic wave is investigated in a plasma with q-nonextensive electrons and two oppositely charged ions with varying masses. These parameters are found to modify the linear dispersion relation and nonlinear solitary structures. The reductive perturbation method is employed to derive modified Korteweg-de Vries (KdV) equation. To solve the obtained governing evolution equation, the exact solution in the planar geometry is obtained and used to obtain an analytical approximate progressive wave solution for the nonplanar evolution equation. The analytical approximate solution so obtained is compared with the numerical solution of the same nonplanar evolution equation and the results are presented in 2D and 3D figures. The results revealed that both solutions are in good agreement. A parametric study is carried out to investigate the effect of different physical parameters on the nonlinear evolution solution behavior. The obtained solution allows us to study the impact of various plasma parameters on the behavior of the nonplanar ion-acoustic solitons. The suitable application of the present investigations can be found in laboratory plasmas, where oppositely charged ions and nonthermal electrons dwell.Yayın Analysis of Nonlinear Dynamics of Neural Networks(Hindawi Publishing Corporation, 2013) Arik, Sabri; Park, Juhyun; Huang, Tingwen; Oliveira, José J[No abstract available]Yayın Patient-centered outcomes of vertebroplasty via questionnaire(Galenos, 2019) Karaca, Sinan; Erdem, Mehmet NuriPurpose: Our aim was to evaluate patient centred outcomes of patients with compression fractures treated by vertebroplasty. Methods: Patients with compression fractures treated by vertebroplasty procedure between 2013- 2016 was examined with a 3-question through telephone call. Results: Fifty-two patients completed the telephone satisfaction survey. Of these, 92.5 % of answerers said the procedure was acceptable, 86.5% had full or partial pain remission and 78.8 % would have the procedure again. Conclusions: The use of vertebroplasty is supported by randomized trials in osteoporotic and malignant compression fractures. To the results of our study, patients believe vertebroplasty is a tolerable procedure that produces full or partial pain remission and would try the same procedure again if needed.Yayın A Comparison of high viscosity and low viscosity bone cement vertebroplasty for severe osteoporotic vertebral compression fractures(Galenos, 2019-01) Karaca, Sinan; Öztermeli, Ahmet; Akpolat, Ahmet Onur; Erdem, Mehmet Nuri; Aydoğan, MehmetIntroduction: Our aim in this clinical trial was to compare the safety and efficacy of highviscosity cement (HVC) with low-viscosity cement (LVC) for the treatment of osteoporotic vertebrae fractures in terms of pain, functional capacity and cement leakage in the percutaneous vertebroplasty procedure (PVP). Methods: From March 2013 to February 2015, 76 patients with vertebrae compression fracture who were admitted into hospital and treated with PVP were reviewed. Pre- and postoperative clinical characteristics of each patient were obtained by using The Visual Analog Scale (VAS) score to evaluate back pain, Oswestry Disability Index (ODI) as a functional assessment. Cement leakage,injected cement volume and the complications assessed due to medical records. Results: VAS and ODI scores improved (P<0.05) significantly in the two groups postoperatively on the other hand there was no significant change between two groups (P>0.05).Paravertebral cement leakage was significantly higher in the LVC group (P<0.05). Pulmonary cement embolism was also significantly higher in LVC group (P<0.05). Conclusion: HVC had lower complication rates with similar clinical results in the comparison with LVC.Yayın Evaluation of satisfaction with a questionnaire according to fracture level and fracture type of patients who underwent balloon kyphoplasty(Galenos Publishing House, 2022-04) Kültür, Yiğit; Bal, Emre; Erdem, Mehmet Nuri; Tezer, MehmetObjective: The aim of this study is to better understand which type of fracture and localization have more painful or worse outcomes for the kyphoplasty procedure. Materials and Methods: Kyphoplasty cases operated between 2013 and 2018 were included in the study. The patients were contacted through the numbers registered in the hospital system. A questionnaire were asked to the patients. Patients were grouped according to gender, fracture level (T12-L1 and others) and fracture type (Osteoporotic, trauma, malignancy, unknown). Results: Fourty-one patients were included in the study. Three-quarters of the patients were women and average age was 62. Ninety-two percent of the patients stated that the pain of the procedure was tolerable. Seventy percent reported that their pain decreased after the procedure and 75% of the patients stated that they could have this procedure done again. Pain reduction and the desire to have same surgery again were significantly higher in female patients than in the male group (p<0.05). In the T12-L1 group and osteoporotic fracture group, the procedure was more easily tolerated, the pain was relieved more and the desire to have the same surgery was higher (p<0.05). Conclusion: Kyphoplasty is accepted as an operation that is well tolerated by patients and has good pain relief. Additionally more detailed information was obtained about the patient’s complaints after the kyphoplasty procedure, according to the fracture level and type.Yayın Beden imgesi ile sosyal anksiyete arasındaki ilişkide kişilik özelliklerinin biçimlendirici etkisi(Cyprus Mental Health Institute, 2020-12) Güney, Cansu; Aktan, Zekeriya Deniz; Yardımcı, EdaKişilik özellikleri, sosyal anksiyete ve beden imgesi arasındaki ilişkiye odaklanan bu araştırmanın temel amacı; Türkiye’de yaşayan ve yaşları 15 ile 18 arasında değişen ergenlerin sahip oldukları kişilik özelliklerinin, beden imgesi algılarına ve sosyal anksiyete yaşama düzeylerine olan etkisinin ölçülmesidir. Örneklemini İstanbul ilinde yaşayan 15-18 yaş arası 300 katılımcının oluşturduğu bu çalışmada, Beş Faktör Kişilik Envanteri (5FKE), Vücut Algısı Ölçeği (VAÖ) ve Ergenler İçin Sosyal Kaygı Ölçeği (EİSKÖ) kullanılmıştır. Verilerin değerlendirilmesinde moderatör etki analizi için değişkenler arası ilişki “Pearson Korelasyon Analizi” tekniğiyle incelenmiş ve “Doğrusal Hiyerarşik Regresyon” analiz adımları izlenmiştir. İlk adımda değişkenler arasındaki ilişkiler incelenmiş ve beden imgesi ile sosyal anksiyete arasında (r=-.138, p<.05) ve sosyal kaygı toplam puanları ile kişilik özelliklerinden dışadönüklükük (r=-.298, p<.001), uyumluluk (r=-.255, p<.001), duygusal dengesizlik (r=-.348, p<.001), deneyime açık olma (r=-.295, p<.001) arasında anlamlı ilişkiler bulunmuştur. Beden imgesi ile sosyal kaygı toplam puanları arasındaki ilişkide Beş Faktör Kişilik Envanteri alt boyutlarının biçimlendirici etkilerine bakıldığında, beden imgesinin sosyal kaygı üzerinde anlamlı bir yordayıcı etkiye sahip olduğu (F(1, 298)=5.753, p<.05), fakat bu ilişki üzerinde biçimlendirici etkileri incelenen kişilik özelliği değişkenlerinden sadece sorumluluğun biçimlendirici etkisinin anlamlı olduğu görülmüştür (F(1,296)= 7.582, p<.05).
