Scopus İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8651

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Theoretical and Numerical Analysis of Fractal Fractional Model of Tumor-Immune Interaction With Two Different Kernels
(Elsevier, 2022) Ahmad, Shabir; Ullah, Aman; Akgu, Ali; Baleanu, Dumitru
Fractal fractional operators in Caputo and Caputo-Fabrizio sense are being used in this manuscript to explore the interaction between the immune system and cancer cells. The tumour-immune model has been investigated numerically and theoretically by the singular and nonsingular fractal fractional operators. Via fixed point theorems, the existence and uniqueness of the model under the Caputo fractal fractional operator have been demonstrated. Using the fixed point theory, the existence of a unique solution has been derived under the Caputo-Fabrizio case. Through nonlinear analysis, the Ulam-Hyres stability of the model has been derived. For the singular and nonsingular fractal fractional operators, numerical results have been developed by Lagrangian-piece wise interpolation. We simulate the numerical results for the various sets of fractional and fractal orders to describe the relationship between immune and cancer cells under the novel operators with two different kernels. We compared the dynamics of the tumor-immune model using a power law and an exponential-decay kernel to explore that the nonsingular fractal fractional operator provides better dynamics for the considered model. (C) 2021 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Alexandria University
Some Observations on Ifrs 15 and Ifrs 16 in the Airline Industry: the Case of Air France - Klm
(Emerald Group Publishing Ltd, 2022) Ozturk, Can
This chapter focuses on the IFRS 15 Revenue from Contracts with Customers and IFRS 16 Leases in the airline industry considering the case of Air France - KLM (AF-KLM). This airline timely adopted IFRS 15 and early adopted IFRS 16 for the year 2018 and restated its 2017 financial statements using the full retrospective method so that the 2018 financial statements of the airline provide comparative financial information during the transition phase from IAS 18 to IFRS 15 as well as from IAS 17 to IFRS 16. In the first part of the chapter, liquidity, solvency, and profitability ratios along with cash flow ratios were used to analyze the cumulative effect of IFRS 15 and IFRS 16 using 2017 and restated 2017 financial statements. In this context, results indicate that the liquidity ratios decreased, and the solvency ratios increased in general. In addition, the cumulative effect of IFRS 15 and IFRS 16 created an upward change in general on profitability ratios based on the several performance parameters that should be considered during the transition from IAS 18 to IFRS 15 and from IAS 17 to IFRS 16. Overall, IFRS 15 has minor effect and IFRS 16 has major effect on the financial statements of AF-KLM. In the second part of the chapter, the compliance level of the mandatory disclosures requirements of the airline was examined from the lessee standpoint and the research pointed out that the airline fully complied with these disclosures at its first adoption of IFRS 16 and provided some voluntary disclosures as well.
Novel Diamond Alpha Bennett-Leindler Type Dynamic Inequalities and Their Applications
(Springernature, 2022) Kayar, Zeynep; Kaymakcalan, Billur
For the exponent zeta > 1, the diamond alpha Bennett-Leindler type inequalities are established by developing two methods, one of which is based on the convex linear combinations of the related delta and nabla inequalities, while the other one is new and is implemented by using time scale calculus rather than algebra. These inequalities can be considered as the complementary to the classical ones obtained for 0 < zeta < 1. Since both methods provide different diamond alpha Bennett-Leindler type inequalities, we can obtain various diamond alpha unifications of the known delta and nabla BennettLeindler type inequalities. Moreover, the second method offers new Bennett-Leindler type inequalities even for the special cases such as delta and nabla ones. Moreover, an application of dynamic Bennett-Leindler type inequalities to the oscillation theory of the second-order half linear dynamic equation is developed and presented for the first time ever.
Intensity Fluctuations of Flat-Topped Beam in Non-Kolmogorov Weak Turbulence: Reply
(Optical Soc Amer, 2012) Gercekcioglu, Hamza; Baykal, Yahya
In our recent publication, we have examined the intensity fluctuations of flat-topped beam in non-Kolmogorov weak turbulence [J. Opt. Soc. Am. A 29, 169 (2012)] in which our comparison of the scintillation indices in the Kolmogorov and in various non-Kolmogorov turbulences was based on the same structure constant, no matter what power law the non-Kolmogorov spectrum takes. In such choice of the fixed structure constant, which is also being used by many researchers in the field [Opt. Express 18, 451 (2010); Proc. SPIE 6747, 67470B (2007); Opt. Commun. 285, 880 (2012)], we have found that the variation of the scintillation index against non-Kolmogorov power law exhibits a peak at the worst power law, which happens to be smaller than the Kolmogorov power law of 11/3. Charnotskii commented [J. Opt. Soc. Am. A. 29, 1838 (2012)] on our paper. In this paper, in our to reply to Charnotskii's comment, we have re-evaluated the scintillation index of flat-topped beam in non-Kolmogorov weak turbulence by employing our recently reported equivalent structure constant [Opt. Lett. 36, 4554 (2011)] and re-compared the intensity fluctuations in Kolmogorov and in non-Kolmogorov turbulences. As the result of such re-comparison, the worst power law is observed to disappear. c 2012 Optical Society of America
A Simple Analytical Eam Model for Some Bcc Metals (Retraction of Vol 15, Pg 1259, 2010)
(Elsevier Science Bv, 2011) Dursun, Ibrahim H.; Guvenc, Ziya B.; Kasap, E.
Diffraction of Waves by an Impedance Half-Plane
(Elsevier Science Bv, 2013) Umul, Y. Z.
The solution of the diffraction problem of waves by an impedance half-plane that satisfies the impedance boundary condition is obtained for the first time in the literature. A reflection coefficient which is the function of the angular and spatial variables in the polar coordinates is defined and its exact expression is obtained with the aid of the impedance boundary condition. The resultant diffraction field is compared with the solution of Malyuzhinets numerically and their differences are stressed. The structures of the total scattered, geometrical optics and diffracted waves are also investigated. (C) 2013 Elsevier B.V. All rights reserved.
Common Fixed Point Theorems in Modified Intuitionistic Fuzzy Metric Spaces (Vol 2013, 189321, 2013)
(Hindawi Publishing Corporation, 2014) Manro, Saurabh; Kumar, Sanjay; Bhatia, S. S.; Tas, Kenan
A Modified Generalized Laguerre Spectral Method for Fractional Differential Equations on the Half Line
(Hindawi Ltd, 2013) Baleanu, D.; Bhrawy, A. H.; Taha, T. M.
This paper deals with modified generalized Laguerre spectral tau and collocation methods for solving linear and nonlinear multiterm fractional differential equations (FDEs) on the half line. A new formula expressing the Caputo fractional derivatives of modified generalized Laguerre polynomials of any degree and for any fractional order in terms of the modified generalized Laguerre polynomials themselves is derived. An efficient direct solver technique is proposed for solving the linear multiterm FDEs with constant coefficients on the half line using a modified generalized Laguerre tau method. The spatial approximation with its Caputo fractional derivatives is based on modified generalized Laguerre polynomials L-i((alpha,beta)) (x) with x is an element of Lambda = (0, infinity), alpha > -1, and beta > 0, and i is the polynomial degree. We implement and develop the modified generalized Laguerre collocation method based on the modified generalized Laguerre-Gauss points which is used as collocation nodes for solving nonlinear multiterm FDEs on the half line.
Retracted: Retracted: Fuzzy Fractional Ostrowski Inequality With Caputo Differentiability (Retracted Article. See 2013)
(Springeropen, 2013) Allahviranloo, Tofigh; Avazpour, Lutfi; Ebadi, Mohammad J.; Baleanu, Dumitru; Salahshour, Soheil
The use of fractional inequalities in mathematical models is increasingly widespread in recent years. In this manuscript, we firstly propose the right Caputo derivative of fuzzy-valued functions about fractional order v (0 < v < 1). To this end, we consider two types of differentiability (similar to the non-fractional case). Then we derive the equivalent integral forms of original fuzzy fractional differential equations. Finally, we prove the fuzzy Ostrowski inequality involving three functions under Caputo's differentiability. In this regard, we state some new results.
Auction-Based Serious Game for Bug Tracking
(Wiley, 2019) Usfekes, Cagdas; Tuzun, Eray; Yilmaz, Murat; Macit, Yagup; Clarke, Paul
Today, one of the challenges in software engineering is utilising application lifecycle management (ALM) tools effectively in software development. In particular, it is hard for software developers to engage with the work items that are appointed to themselves in these ALM tools. In this study, the authors have focused on bug tracking in ALM where one of the most important metrics is mean time to resolution that is the average time to fix a reported bug. To improve this metric, they developed a serious game application based on an auction-based reward mechanism. The ultimate aim of this approach is to create an incentive structure for software practitioners to find and resolved bugs that are auctioned where participants are encouraged to solve and test more bugs in less time and improve quality of software development in a competitive environment. They conduct hypothesis tests by performing a Monte Carlo simulation. The preliminary results of this research support the idea that using a gamification approach for an issue tracking system enhances the productivity and decreases mean time to resolution.
Uniform Theory for the Diffraction of Evanescent Plane Waves: Publisher's Note (Vol 24, Pg 2426, 2007)
(Optical Soc Amer, 2007) Umul, Yusuf Z.
Soccer Causes Degenerative Changes in the Cervical Spine
(Springer, 2004) Kartal, A; Yildiran, I; Senköylü, A; Korkusuz, F
Background. Radiological changes and degeneration of the cervical spine have been previously described in soccer players. The onset of such changes was 10-20 years earlier than that of the normal population. The aim of this study was to assess these early degenerative changes in amateur active and veteran soccer players in a cross-sectional descriptive study using biomechanical, radiological, and magnetic resonance measures. Methods. The subjects were active (<30 years; n=15) and veteran (>30 years; n=15) male amateur soccer players, and their age-matched controls (n=13 and n=15). Biomechanical measurements were made on a cervical dynamometer. Dynamic radiological and magnetic resonance findings were also obtained and evaluated. Results. The normalized mean extension moment was higher in the active soccer players, but the mean range of motion was lower. Degenerative changes were prominent in veteran players, and the sagittal diameter of their spinal canal at C2 to C6 was lower when compared to active players and controls. Magnetic resonance findings of degeneration were more prominent in soccer players when compared to their age-matched controls. Conclusion. A tendency towards early degenerative changes exists in soccer players most probably due to high- and/or low-impact recurrent trauma to the cervical spine caused by heading the ball.
O(N) Parallel Tight Binding Molecular Dynamics Simulation of Carbon Nanotubes
(Elsevier, 2002) Özdogan, C; Dereli, G; Çagin, T
We report an O(N) parallel tight binding molecular dynamics simulation study of (10 x 10) structured carbon nanotubes (CNT) at 300 K. We converted a sequential O(N-3) TBMD simulation program into an O(N) parallel code, utilizing the concept of parallel virtual machines (PVM). The code is tested in a distributed memory system consisting of a cluster with 8 PC's that run under Linux (Slackware 2.2.13 kernel). Our results on the speed up, efficiency and system size are given. (C) 2002 Elsevier Science B.V. All rights reserved.
Feedforward Strategies for Cooperative Adaptive Cruise Control in Heterogeneous Vehicle Strings
(Ieee-inst Electrical Electronics Engineers inc, 2018) Al-Jhayyish, Ahmed M. H.; Schmidt, Klaus Werner
String stability is an essential property to ensure that the fluctuations are attenuated along vehicle strings. This paper focuses on the fulfillment of string stability in the practical case of heterogeneous vehicle strings that comprise vehicles with different dynamic properties. Using the idea of predecessor following, acceleration feedforward, predicted acceleration feedforward, and input signal feedforward are considered as different possible feedforward strategies. For all strategies, the parameter ranges of predecessor vehicles that ensure string stability of a given vehicle are characterized, computed, and validated by simulation.
Some fixed point results for T A C -type contractive mappings
(Hindawi Ltd, 2016) Chandok, Sumit; Taş, Kenan; Tas, Kenan; Ansari, Arslan Hojat; 4971
We prove some fixed point results for new type of contractive mappings using the notion of cyclic admissible mappings in the framework of metric spaces. Our results extend, generalize, and improve some well-known results from literature. Some examples are given to support our main results.
Virtual business operations, e-commerce & its significance and the case of Turkey: Current situation and its potential
(Springer, 2012) Gokmen, Aytac; Gökmen, Aytaç; 17660
21(st) century is the age of high technologies penetrated into business leading to virtual businesses and e-commerce applications combined with electronic business (e-business) structures. Virtual businesses are independent and/or partly dependent organizations that have flexible and agile structures to respond the altering business conditions. Yet, electronic commerce (e-commerce) is the exchange of goods and services over the Internet. Both virtual businesses and e-commerce operations enable organizations to have fluid structures, modify the changing conditions, lower expenses, access to new markets and attain new consumers. The e-commerce applications have also been increasing in Turkey at a great pace but not significantly when compared to the total trade volume. For, the aim of this paper is to focus on the virtual businesses, e-commerce, harmonization of the conventional business structures with e-commerce and emphasize the importance of the e-commerce applications in Turkey resting on dependable national and international publications and data. With respect to the research made, it is possible to state that the e-commerce volume of Turkey is increasing as a remedy to cover the foreign trade deficit, but it is still not sufficient when compared to the total trade volume. Additionally, even though Turkey possesses an efficient e-government mechanism and e-signature law to enhance the volume of its e-commerce, the lack of cooperation among parties and standardization as well as the difficulty in adoption of digital transactions would be issues to be tackled in order to develop e-commerce in Turkey.
Predicting the severity of COVID-19 patients using a multi-threaded evolutionary feature selection algorithm
(Wiley, 2022) Deniz, Ayca; Dökeroğlu, Tansel; Kiziloz, Hakan Ezgi; Sevinc, Ender; Dokeroglu, Tansel; 234173
The COVID-19 pandemic has huge effects on the global community and an extreme burden on health systems. There are more than 185 million confirmed cases and 4 million deaths as of July 2021. Besides, the exponential rise in COVID-19 cases requires a quick prediction of the patients' severity for better treatment. In this study, we propose a Multi-threaded Genetic feature selection algorithm combined with Extreme Learning Machines (MG-ELM) to predict the severity level of the COVID-19 patients. We conduct a set of experiments on a recently published real-world dataset. We reprocess the dataset via feature construction to improve the learning performance of the algorithm. Upon comprehensive experiments, we report the most impactful features and symptoms for predicting the patients' severity level. Moreover, we investigate the effects of multi-threaded implementation with statistical analysis. In order to verify the efficiency of MG-ELM, we compare our results with traditional and state-of-the-art techniques. The proposed algorithm outperforms other algorithms in terms of prediction accuracy.
Predicting Financial Failure Of The Turkish Banks
(World Scientific Publ Co Pte Ltd, 2006) Doganay, M. Mete; Ceylan, Nildag Basak; Aktas, Ramazan; 112010
Banks are the most important financial institutions in Turkey because other financial institutions are not developed efficiently yet. Turkish banks experienced financial difficulties and a substantial amount of banks failed in the past. This event urged the government to initiate measures to prevent banks from getting into financial difficulties. As a result of these measures, Turkish banking system currently seems to be very attractive for the foreign investors willing to invest in this sector. One of the main concerns of the foreign investors is a possibility of a new banking crisis although it is very remote at this time. The purpose of this study is to develop early warning systems predicting the financial failure at least three years ahead of financial date. A number of multivariate statistical models such as multiple regression, discriminant analysis, logit, probit are used. We found that the most appropriate model is logit. The significant variables obtained from the models explain very well the causes of the bank failures. Our models can be used to assist interested parties to predict the probability of financial failure of Turkish banks.
On Transformation Involving Basic Analogue to the Aleph-Function of Two Variables
(Mdpi, 2022) Kumar, Dinesh; Baleanu, Dumitru; Baleanu, Dumitru; Ayant, Frederic; Suedland, Norbert; 56389
In our work, we derived the fractional order q-integrals and q-derivatives concerning a basic analogue to the Aleph-function of two variables (AFTV). We discussed a related application and the q-extension of the corresponding Leibniz rule. Finally, we presented two corollaries concerning the basic analogue to the I-function of two variables and the basic analogue to the Aleph-function of one variable.
On dynamic systems in the frame of singular function dependent kernel fractional derivatives
(Mdpi, 2019) Abdeljawad, Thabet; Abdeljawad, Thabet; Madjidi, Fadila; Jarad, Fahd; Jarad, Fahd; Sene, Ndolane; 234808
In this article, we discuss the existence and uniqueness theorem for differential equations in the frame of Caputo fractional derivatives with a singular function dependent kernel. We discuss the Mittag-Leffler bounds of these solutions. Using successive approximation, we find a formula for the solution of a special case. Then, using a modified Laplace transform and the Lyapunov direct method, we prove the Mittag-Leffler stability of the considered system.

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