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Yayın Asymptotic solutions of love wave propagation in a covered half-space with inhomogeneous initial stresses G(3)(1)(Işık University Press, 2015) Hasanoğlu, Elman; Negin, MasoudThe dispersive behavior of Love waves in an elastic half-space substrate covered by an elastic layer under the effect of inhomogeneous initial stresses has been investigated. Classical linearized theory of elastic waves in initially stressed bodies for small deformations is used and the well-known WKB high-frequency asymptotic technique is applied for the theoretical derivations. Numerical results on the action of the influence of the initial stresses on the wave propagation velocity for a geophysical example are presented and discussed.Yayın The dynamic relationship between technological change and employment: a comparison of youth and total employment using panel VAR approach and causality analysis(Sosyoekonomi Derneği, 2022-10) Görkey, SeldaThis study empirically examines the relationship and causality between technological change and employment by comparing youth and total employment. It covers data from 16 OECD economies from 1985 to 2018 and uses multifactor productivity (MFP) as a proxy for technological change. The findings from the general method of moments panel vector autoregression (GMM Panel-VAR) approach indicate significant and positive effects of MFP on youth and total employment, and a significant yet negative impact of youth employment on MFP. According to Panel-VAR-Granger- Causality analysis results, there is a two-way causality between MFP and youth employment and a one-way causality from MFP to total employment. Thus, this study empirically confirms the jobcreation effect of technology and finds out that the technological change and employment nexus differs for youth employment compared to that for total employment.Yayın An approximate wave solution for perturbed KDV and dissipative NLS equations: weighted residual method(Işık University Press, 2019-06-21) Demiray, HilmiIn the present work, we modified the conventional "weighted residual method" to some nonlinear evolution equations and tried to obtain the approximate progressive wave solutions for these evolution equations. For the illustration of the method we studied the approximate progressive wave solutions for the perturbed KdV and the dissipative NLS equations. The results obtained here are in complete agreement with the solutions of inverse scattering method. The present solutions are even valid when the dissipative effects are considerably large. The results obtained are encouraging and the method can be used to study the cylindrical and spherical evolution equations.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 Psychometric properties of the pathological buying screener: reliability and validity study(Kare Publishing, 2021-06) Dikbaş, Ganime Tuba; Acartürk, Ceren; Akyunus, MirayObjective: The Pathological Buying Screener (PBS) is a self-report scale used to evaluate compulsive buying behavior. The aim of this study was to assess the validity and reliability of a Turkish version of the PBS in a nonclinical sample. Method: A total of 457 adult participants aged 18-64 years were enrolled in this study. Internal consistency, test-retest reliability and structure, concurrent and criterion-related predictive validity analyses were conducted to ensure reliability and validity for use of the scale with a Turkish population. As part of the validity study, all of the participants were asked to complete a battery of self-report scales: the Compulsive Buying Scale, the Brief Symptom Inventory, the Rosenberg Self-Esteem Scale, the Barratt Impulsiveness Scale-Short Form, and the PBS. In order to examine the test-retest reliability, 75 participants were asked to complete the questionnaire once again 2 weeks after the first administration. Results: The results of this study revealed that the PBS had good internal consistency and test-retest reliability. The findings supported concurrent and criterion-related predictive validity, and a 2-factor structure, consistent with the original form. Conclusion: The Turkish version of the PBS is a valid and reliable measurement tool that will add to understanding of pathological buying behavior.Yayın Extremum seeking control of uncertain systems(Işık University Press, 2017) Dinçmen, ErkinExtremum seeking is used in control problems where the reference trajectory or reference set point of the system is not known but it is searched in real time in order to maximize or minimize a performance function representing the optimal behaviour of the system. In this paper, extremum seeking algorithm is applied to the systems with parametric uncertainties.Yayın Measurement of perceived psychological safety: integration, review and evidences for the scale in the context of Turkiye(İstanbul Üniversitesi Yayınevi, 2022-06-22) Bülbül, Seçil; İşiaçık, Serin; Aytaç, SerpilPsychological safety can predict many positive individual and organizational outcomes at work, and previous research addressed how psychological safety contributes to positive work attitudes and behaviors. In Turkey, there is quite an amount of research showing the contributing role of psychological safety perception on employees' positive performance behaviors and organizational effectiveness and innovativeness. However, previous research in Turkey does not adequately show the reliability and validity of the psychological safety scale, which was developed by Edmondson (1999). Based on the suggested requirement this study aimed to investigate the psychological safety perceptions of individuals who work in various sectors in Turkey. The adapted version of the psychological safety scale was used to gain evidence for the reliability and validity of the instrument in Turkey. In total, 585 individuals working in various industries and from various occupational groups participated in the research. Both exploratory factor analysis and the confirmatory factor analysis showed that Turkish adapted version of the psychological safety scale was valid and reliable.Yayın A new subspecies of Phoenix theophrasti Greuter (Phoenix theophrasti Greuter subsp. golkoyana Boydak) from Turkey(Istanbul Univ-Cerrahpasa, 2019-07) Boydak, MelihIn the present study, a new subspecies (Phoenix theophrasti Greuter subsp. golkoyana Boydak) is described in Turkey. The unidentified Phoenix taxon native to Bodrum-Golkoy, Aegean Turkey and named as the "Golkoy Phoenix population" has been known to Golkoy's inhabitants for centuries. The Golkoy Phoenix population was considered to be representative of P. theophrasti. Boydak made the first of a number of trips to Golkoy and immediately noticed some distinct differences between the Golkoy Phoenix population, P. theophrasti Greuter, and Phoenix dactylifera L in the early summer of 1990. He continued his investigations on this taxon for many years to shed light on the subject. He made two new trips to the three native stands of P. theophrasti and the Golkoy Phoenix populations in 2015 and 2018. Measurements and observations were made on the morphological characteristics that showed distinct differences among the Golkoy Phoenix population, P. theophrasti, and P. dactylifera. These were related to the length of male stalks and female inflorescences and some fruit and seed characteristics. The results indicate that some distinctive morphological characteristics of the "Golkoy Phoenix population" merit its being described as a new subspecies. "Phoenix theophrasti Greuter subsp. golkoyana Boydak" differs from P. theophrasti Greuter with respect to its longer fruiting-female stalk length and longer male stalk length, its fruiting stalks hold fruits marginally higher, and its having seeds with slightly visible striate surface crust structures and deeper-wider grooves.Yayın Tulczyjew's triplet for Lie groups III: higher order dynamics and reductions for iterated bundles(Serbian Society of Mechanics, 2021) Esen, Oğul; Gümral, Hasan; Sütlü, SerkanGiven a Lie group G, we elaborate the dynamics on T*T*G and T*TG, which is given by a Hamiltonian, as well as the dynamics on the Tul-czyjew symplectic space TT * G, which may be defined by a Lagrangian or a Hamiltonian function. As the trivializations we adapted respect the group structures of the iterated bundles, we exploit all possible subgroup reductions (Poisson, symplectic or both) of higher order dynamics.Yayın ABD’nin Irak müdahalesinde güvenliğin özelleşmesi: Sözleşmeli personel ve özel askeri ve güvenlik şirketlerinin rolü ve etkileri(Istanbul Univ, 2020-03-30) Çağlar, Mehmet TuranABD’nin 2003 yılında Irak’a müdahalesi ile birlikte özel askeri ve güvenlik şirketleri, ABD’nin en önemli ortaklarından biri olmuş ve hatta sözleşmeli personel, Irak’ta koalisyon güçleri içerisinde ABD’den sonraki en büyük grup haline gelmiştir. 2003 yılı sonrası ABD yönetimleri, Irak Savaşı’nın artan ekonomik, insani ve siyasi maliyetlerini sözleşmeli personel üzerinden dışsallaştırmaya çalışmıştır. 2011 yılı öncesi Irak’ta ABD askerlerinin yanında yer alan sözleşmeli personel, 2011 yılı sonrası ABD askerlerinin yerine görev almaya başlamıştır. ABD yönetimleri, özel şirketler aracılığıyla bazı maliyetleri dışsallaştırabilse de sözleşmeli personelin insan hakları ihlalleri, ABD’nin Irak ve bölgedeki ününe zarar vermiştir. Sözleşmeli personel ayrıca Irak’ta şiddet uygulayan ve şiddete maruz kalan aktörlerin başında gelmiş ve ülke içerisindeki şiddetin yükselmesinde rol oynamıştır. Irak’ta ABD aracılığıyla güvenliğin özelleşmesi ise Irak’taki güvenlik kavramını dönüştürmüştür. Özel askeri ve güvenlik şirketleri ve çalışanlarının hukuki statüleri ve denetimleri, güvenlik kavramının dışlayıcı bir hale gelmesi ve güvenliğin piyasalaşması, Irak gibi kırılgan bir ülkede yeni güvenlik sorunlarına yol açmıştır. Özel askeri ve güvenlik şirketlerinin Irak Savaşı boyunca oynadığı roller ise geleneksel güvenlik anlayışı ve şiddet kullanma tekelinin devriyle ilgili Uluslararası İlişkilerde yeni tartışmalara sebep olmuştur.
