PubMed İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8650

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Adaptive fractional-order blood glucose regulator based on high-order sliding mode observer
(inst Engineering Technology-iet, 2019) Delavari, Hadi; Baleanu, Dumitru; Heydarinejad, Hamid; Baleanu, Dumitru; 56389
Type I diabetes is described by the destruction of the insulin-producing beta-cells in the pancreas. Hence, exogenous insulin administration is necessary for Type I diabetes patients. In this study, to estimate the states that are not directly available from the Bergman minimal model a high-order sliding mode observer is proposed. Then fractional calculus is combined with sliding mode control (SMC) for blood glucose regulation to create more robustness performance and make more degree of freedom and flexibility for the proposed method. Then an adaptive fractional-order SMC is proposed. The adaptive SMC protect controller against disturbance and uncertainties while the fractional calculus provides robust performance. Numerical simulation verifies that the proposed controllers have better performance in the presence of disturbance and uncertainties without chattering.
Analysis for Fractional-Order Predator–Prey Model With Uncertainty
(inst Engineering Technology-iet, 2019) Narayanamoorthy, Samayan; Baleanu, Dumitru; Baleanu, Dumitru; Thangapandi, Kalidas; Perera, Shyam Sanjeewa Nishantha; 56389
Here, the authors analyse the fractional-order predator-prey model with uncertainty, due to the vast applications in various ecological systems. The most of the ecological model do not have exact analytic solution, so they proposed a numerical technique for an approximate solution. In the proposed method, they have implemented the higher order term into the fractional Euler method to enhance the precise solution. Further, the present attempt is aimed to discuss the solutions of the FPPM with uncertainty (fuzzy) initial conditions. The initial conditions of the predator-prey model were taken as fuzzy initial conditions due to the fact that the ecological model highly depends on uncertain parameters such as growth/decay rate, climatic conditions, and chemical reactions. Finally, the numerical example manifest that the proposed method is authentic, applicable, easy to use from a computational viewpoint and the acquired outcomes are balanced with the existing method (HPM), which shows the efficiency of the proposed method.
Chemometric Determination of Naproxen Sodium and Pseudoephedrine Hydrochloride in Tablets by HPLC
(Pharmaceutical Soc Japan, 2006) Dinç, E; Baleanu, Dumitru; Özdemir, A; Aksoy, H; Üstündag, Ö; Baleanu, D; 6981; 26096; 105547
A new chemometric determination by high-performance liquid chromatography (HPLC) with photodiode array (PDA) detection was implemented for the simultaneous determination of naproxen sodium and pseudoephedrine hydrochloride in tablets. Three chemometric calibration techniques, classical least squares (CLS), principle component regression (PCR) and partial least squares (PLS) were applied to the peak area at multiwavelength PDA detector responses. The combinations of HPLC with chernometric calibration techniques were called HPLC-CLS, HPLC-PCR and HPLC-PLS. For comparison purposes the HPLC method called the classic HPLC method was used to confirm the results obtained from combined HPLC-chemometric calibration techniques. A good chromatographic separation between two drugs with losartan potassium as an internal standard was achieved using a Waters Symmetry (R) C18 Column 5 mu m 4.6 +/- 250 mm and a mobile phase containing 0.2 m acetate buffer and acetonitrile (v/v, 40 : 60). The multiwavelength PDA detection was measured at five different wavelengths. The chromatograms were recorded as a training set in the mobile phase. Three HPLC-chemometric calibrations and the classic-HPLC method were used to test the synthetic mixtures of naproxen sodium and pseudoephedrine hydrochloride in the presence of the internal standard. The HPLC-chemometric approaches were applied to real samples containing drugs of interest. The experimental results obtained from HPLC-chemometric calibrations were compared with those obtained by a classic HPLC method.
Competitive Analysis for Stochastic Influenza Model With Constant Vaccination Strategy
(inst Engineering Technology-iet, 2019) Baleanu, Dumitru; Baleanu, Dumitru; Raza, Ali; Rafiq, Muhammad; Arif, Muhammad Shoaib; Ali, Muhammad Asghar; 56389
This manuscript discusses a competitive analysis of stochastic influenza model with constant vaccination strategy. The stochastic influenza model is comparatively more pragmatic versus the deterministic influenza model. The effect of influenza generation number holds in the stochastic model. If the value of this number is less than one, this situation will help us to control the disease in a population. A greater than one value of this threshold number shows the persistence of disease to become endemic. The proposed structure for the stochastic influenza model as stochastic non-standard finite difference scheme conserve all vital characteristics like positivity, boundedness and dynamical consistency defined by Mickens.
Competitive Numerical Analysis for Stochastic Hıv/Aıds Epidemic Model in A Two-Sex Population
(inst Engineering Technology-iet, 2019) Raza, Ali; Baleanu, Dumitru; Rafiq, Muhammad; Baleanu, Dumitru; Shoaib Arif, Muhammad; Naveed, Muhammad; Ashraf, Kaleem; 56389
This study is an attempt to explain a reliable numerical analysis of a stochastic HIV/AIDS model in a two-sex population considering counselling and antiretroviral therapy (ART). The authors are comparing the solutions of the stochastic and deterministic HIV/AIDS epidemic model. Here, an endeavour has been made to explain the stochastic HIV/AIDS epidemic model is comparatively more pragmatic in contrast with the deterministic HIV/AIDS epidemic model. The effect of threshold number H* holds on the stochastic HIV/AIDS epidemic model. If H* < 1 then condition helps us to control disease in a two-sex human population while H* > 1 explains the persistence of disease in the two-sex human population. Lamentably, numerical methods such as Euler-Maruyama, stochastic Euler, and stochastic Runge-Kutta do not work for large time step sizes. The recommended structure preserving framework of the stochastic non-standard finite difference (SNSFD) scheme conserve all vital characteristics such as positivity, boundedness, and dynamical consistency defined by Mickens. The effectiveness of counselling and ART may control HIV/AIDS in a two-sex population.
Complex degree of coherence for partially coherent general beams in atmospheric turbulence
(Optical Soc Amer, 2007) Eyyuboglu, Halil T.; Baykal, Yahya; Cai, Yangjian; 7688; 7812
With the use of the general beam formulation, the modulus of the complex degree of coherence for partially coherent cosh-Gaussian, cos-Gaussian, Gaussian, annular and higher-order Gaussian optical beams is evaluated in atmospheric turbulence. For different propagation lengths in horizontal atmospheric links, the moduli of the complex degree of coherence at the source and receiver planes are examined when reference points are taken on the receiver axis and off-axis. In the on-axis case, it is observed that in propagation, the moduli of the complex degree of coherence are symmetrical and look like the intensity profile of the related coherent beam propagating in a turbulent atmosphere. For all the beams considered, the moduli of the complex degree of coherence profiles turn into Gaussian shapes beyond certain propagation lengths. In the off-axis case, the moduli of complex degree of coherence patterns become drifted at the earlier propagation lengths. Among the beams investigated, the cos-Gaussian beam is found to be almost independent of the changes in the source partial coherence parameter, and the annular beam seems to be affected the most against the variations of the source partial coherence parameter. (c) 2007 Optical Society of America.
Correlation and structure functions of Hermite-sinusoidal-Gaussian laser beams in a turbulent atmosphere
(Optical Soc Amer, 2004) Baykal, Y
To study the performance of atmospheric optical links by using Hermite-sinusoidal-Gaussian laser beam sources, we derive the log-amplitude and the phase correlation and structure functions of such beams in a turbulent atmosphere. Our formulations correctly reduce to the known higher-order mode correlation and structure functions, which in turn reduce to the fundamental-mode (TEM00-mode) results. Several special cases of our formulation are presented, among which the case involving Hermite-cosh-Gaussian dependence is especially noted, since this case is of interest to us owing to the nature of cosh dependence exhibiting the concentration of the energy in the outer lobes of the beam. (C) 2004 Optical Society of America.
Diffraction of evanescent plane waves by a resistive half-plane
(Optical Soc Amer, 2007) Umul, Yusuf Z.; Umul, Yusuf Ziya; 42699
Diffraction of evanescent plane waves by a resistive half-plane is examined. The scattering integrals are constructed with the modified theory of physical optics. These integrals are evaluated uniformly by using an unusual method. The scattered fields of evanescent waves are obtained by giving the angle of incidence a complex value. The diffracted waves are plotted numerically for different parameters of the incident field. (c) 2007 Optical Society of America.
Diffraction of homogeneous and inhomogeneous plane waves by a planar junction between perfectly conducting and impedance half-planes
(Optical Soc Amer, 2007) Umul, Yusuf Z.; Umul, Yusuf Ziya; 42699
The problem of diffraction of homogeneous and inhomogeneous plane waves at the discontinuity formed by perfectly conducting and impedance half-planes is examined by the method of modified theory of physical optics (MTPO). The MTPO integral of the reflected scattered waves by the perfectly conducting half-plane is reconstructed in order to include the effect of the diffracted wave coming from the edge of the impedance halfplane. The integrals are evaluated by a uniform asymptotic method. The results are plotted numerically and compared with the literature. (C) 2007 Optical Society of America
Diffraction of plane electromagnetic waves by a resistive half-screen for skew incidence
(Optical Soc Amer, 2020) Umul, Yusuf Ziya; Umul, Yusuf Ziya; 42699
The scattering process of electromagnetic plane waves by a resistive half-screen is investigated for oblique incidence. First of all, it is shown that the existing solution in the literature is not correct, because the problem was solved by considering the normal components of the electromagnetic field, in terms of which the boundary conditions cannot be expressed. Instead of these, the components of the electric field, which is parallel to the edge discontinuity, are taken into account. The diffracted fields are obtained with the aid of the method of transition boundary. The uniform field expressions are obtained by using the Fresnel function. The behaviors of the total field and its subcomponents are analyzed numerically. (C) 2019 Optical Society of America
Edge-dislocation waves in the diffraction process by an impedance half-plane
(Optical Soc Amer, 2007) Umul, Yusuf Z.; Umul, Yusuf Ziya; 42699
Edge-dislocation waves, created in the diffraction of plane waves by an impedance half-plane, are examined by the method of modified theory of physical optics. The integrals, obtained by a related technique, are decomposed according to their boundaries and evaluated by using uniform asymptotic methods. The results are plotted and are investigated numerically. (c) 2007 Optical Society of America
Fast fluorometric enumeration of E. coli using passive chip
(Elsevier, 2019) Çoğun, Ferah; Kasap, Esin Nagihan; Dogan, Uzeyir; Yıldırım, Ender; Cogun, Ferah; Yildirim, Ender; Boyaci, Ismail Haklu; Cetin, Demet; Ertas, Nusret
In this report, a passive microfluidic chip design was developed for fast and sensitive fluorometric determination of Escherichia coli (E. coli) based on sandwich immunoassay. Initially, magnetic nanoparticles (MNPs) and chitosan modified mercaptopropionic acid capped cadmium telluride (CdTe) quantum dots (QDs) were functionalized with E.coli specific antibody to form a sandwich immunoassay with the E. coli. The magnetic separation and preconcentration of the E.coli from the sample solution was performed in the vial. Conjugation of QDs to the magnetically captured E. coli and washing were performed using a passive type of microchip. The microfluidic chip consists of four microchambers connected to each other by microchannels which act as capillary valves. Signal measurement was performed at the last chamber by using a hand-held spectrofluorometer equipped with a fiber optic reflection probe. The selectivity of the method was tested with Enterobacter aerogenes (E. aerogenes) and Salmonella enteritidis (S. enteritidis), it was observed that these bacteria have no interference effect on E.coli determination. The calibration curve was found to be linear in the range of 10(1)-10(5) cfu/mL with a correlation coefficient higher than 0.99. The limit of detection was calculated as 5 cfu/mL. The method was successfully applied to spiked tap and lake water samples. The results suggest that the developed method is applicable for on-site E. coli detection and offers several advantages such as large dynamic range, high sensitivity, high selectivity and short analysis time.
Formulation of correlations for general-type beams in atmospheric turbulence
(Optical Soc Amer, 2006) Baykal, Y; 7812
Log-amplitude and phase correlations of general-type beams are formulated in atmospheric turbulence. A general beam is described as the superposition of many sets of multimode contents, each mode being off-axis Hermite-Gaussian. Since the Rytov solution is utilized, the formulas are valid in the weakly turbulent regime. The results are presented in integral forms that should be numerically evaluated for the specific beam type of interest. Our general beam results correctly reduce to the existing solutions for the correlations of limiting-case beams such as higher-order single-mode, multimode, off-axis Hermite-Gaussian, Hermite-sinusoidal-Gaussian, higher-order-annular, flat-topped-Gaussian, and thus naturally fundamental mode, plane, and spherical waves. Scintillation index and phase fluctuations in atmospheric optical links employing such special beams will be examined in future using the results reported here. (c) 2006 Optical Society of America.
Fractional-Continuous Wavelet Transforms and Ultra-Performance Liquid Chromatography for the Multicomponent Analysis of A Ternary Mixture Containing Thiamine, Pyridoxine, and Lidocaine in Ampules
(Oxford Univ Press inc, 2012) Dinc, Erdal; Baleanu, Dumitru; Baleanu, Dumitru; 56389
New chemometric approaches based on the application of partial least squares (PLS) and principal component regression (PCR) algorithms with fractional wavelet transform (FWT) and continuous wavelet transform (CWT) are proposed for the spectrophotometric multicomponent determination of thiamine hydrochloride (B-1), pyridoxine hydrochloride (B-6), and lidocaine hydrochloride (LID) in ampules without any separation step. In this study PLS and PCR techniques were applied to the raw spectral data, FWT-coefficients, and FWT-CWT-coefficients. These calibration models were labeled as Raw-PLS and Raw-PCR, FWT-PLS and FWT-PCR, and FWT-CWT-PLS and FWT-CWT-PCR, respectively. A new ultra-performance liquid chromatographic (UPLC) method was developed for the comparison of the results obtained by applying the chemometric calibration methods. Chromatographic separation and determination of B-1, B-6, and LID in ampules were performed on an Acquity UPLC (R) BEH C18 column (50 x 2.1 mm id, 1.7 mu m particle size) using gradient elution with a mobile phase consisting of methanol and 0.01 M HCl at a constant flow rate of 0.6 mL/min. These combined chemometric calibrations and UPLC were validated by analyzing various ternary mixtures, B-1, B-6, and LID. The proposed chemometric approaches (signal processing-multivariate calibrations) and UPLC method were applied to the quantitative multicomponent analysis of marketed ampules containing the vitamins B1 and B-6 with LID.
Hermite-cosine-Gaussian laser beam and its propagation characteristics in turbulent atmosphere
(Optical Soc Amer, 2005) Eyyuboglu, HT; 7688
Hermite-cosine-Gaussian (HcosG) laser beams are studied. The source plane intensity of the HcosG beam is introduced and its dependence on the source parameters is examined. By application of the Fresnel diffraction integral, the average receiver intensity of HcosG beam is formulated for the case of propagation in turbulent atmosphere. The average receiver intensity is seen to reduce appropriately to various special cases. When traveling in turbulence, the HcosG beam initially experiences the merging of neighboring beam lobes, and then a TEM-type cosh-Gaussian beam is formed, temporarily leading to a plain cosh-Gaussian beam. Eventually a pure Gaussian beam results. The numerical evaluation of the normalized beam size along the propagation axis at selected mode indices indicates that relative spreading of higher-order HcosG beam modes is less than that of the lower-order counterparts. Consequently, it is possible at some propagation distances to capture more power by using higher-mode-indexed HcosG beams. (C) 2005 Optical Society of America.
Hermite-sine-Gaussian and Hermite-sinh-Gaussian laser beams in turbulent atmosphere
(Optical Soc Amer, 2005) Eyyuboglu, HT; Baykal, Y; 7688; 7812
Hermite-sine-Gaussian and Hermite-sinh-Gaussian laser beam intensities in a turbulent atmosphere are investigated. The received intensity is formulated by applying the extended Huygens-Fresnel principle to generalized Hermite-hyperbolic-Gaussian and Hermite-sinusoidal-Gaussian beam incidences. From this result, the association to different types of Hermite-hyperbolic-Gaussian and Hermite-sinusoidal-Gaussian beams are defined. The average receiver intensity expressions for Hermite-sine-Gaussian and Hermite-sinh-Gaussian laser beams are evaluated and plotted against the variations in source parameters and propagation conditions. It is observed that the propagation of Hermite-sine-Gaussian and Hermite-sinh-Gaussian laser beams in turbulence have many similarities to their counterparts, Hermite-cosine-Gaussian and Hermite-cosh-Gaussian laser beams, that are examined earlier. It is further observed that under certain conditions the main features of the previously established reciprocity concept between cosine-Gaussian and cosh-Gaussian beams are mostly applicable to Hermite-sine-Gaussian and Hermite-sinh-Gaussian laser beams. (c) 2005 Optical Society of America.
Linking leadership style and workplace procrastination: The role of organizational citizenship behavior and turnover intention
(Routledge Journals, Taylor & Francis Ltd, 2018) Kose, Asli Goncu; Metin, U. Baran; 166202
The primary aim of the present study was to explore whether paternalistic or transformational leadership styles of supervisors were significantly related to workplace procrastination. Moreover, the potential mediation effects of organizational citizenship behaviors (specifically, civic virtue, and conscientiousness) and turnover intention in the link between leadership style and procrastination of the employees were investigated on a heuristic model. Data was collected through online surveys from 126 Turkish full-time office employees. The goodness-of-fit of the proposed model was tested using structural equation modeling and the mediation analysis was performed by bootstrapping. As expected, transformational leadership and organizational citizenship behaviors were negatively related to workplace procrastination. However, there was no significant link between paternalistic leadership and procrastination. Moreover, turnover intention and organizational citizenship behaviors did not mediate this relationship. These findings suggest that transformational leadership style could be a more effective style for diminishing employees' excessive nonwork related behaviors.
Log-amplitude and phase fluctuations of higher-order annular laser beams in a turbulent medium
(Optical Soc Amer, 2005) Baykal, Y; 7812
Log-amplitude and phase-correlation and structure functions of higher-order annular laser beams in a turbulent atmosphere are derived. A higher-order annular beam source is defined as the superposition of two different higher-order Hermite-Gaussian beams. A special case of such an excitation is the annular Gaussian beam in which two beams operate at fundamental modes of different Gaussian beam sizes, yielding a doughnut-shaped (annular) beam when the second beam is subtracted from the first beam. Our formulation utilizes Rytov approximation, which makes it applicable in the weak-turbulence regime, especially for log-amplitude fluctuations. Limiting cases of our formulations correctly match with known higher-order-mode solutions that in turn reduce to the Gaussian-beam-wave (TEM00-mode) results. Our results can be applied to determine the scintillation index and the phase fluctuations in free-space optics links under higher-order annular laser beam excitation. Except for the numerical evaluation of a specific example covering an annular Gaussian beam, the results in general are left in integral form and need to be numerically evaluated in detail to obtain quantitative results. (c) 2005 Optical Society of America.
Off-axis average transmittance and beam spread of a partially coherent flat-topped beam in a turbulent underwater medium
(Optical Soc Amer, 2019) Keskin, Aysan; Baykal, Yahya; 7812
The effects of oceanic turbulence on the off-axis optical transmittance and beam spread are examined when a partially coherent flat-topped beam wave propagates in an underwater medium. To observe the oceanic turbulence effect, the power spectrum of homogeneous and isotropic oceanic water combining the effects of salinity and temperature is used. Employing the extended Huygens-Fresnel integral and Carter's definition for the general beam formulation that is applied to a partially coherent flat-topped beam, the effects of the parameters of power spectrum, the link on the off-axis average transmittance, and beam spread are analyzed. The results obtained with the help of the MATLAB program indicate that if the flatness of the optical beam increases, the average transmittance increases, and the beam spread decreases. Partial coherence is found to be inversely proportional to the average transmittance and directly proportional to beam spread. Increase in the source size is found to increase the average transmittance and to reduce the beam spread. Loss of the kinetic energy of fluid causes less turbulence. The rate of dissipation of kinetic energy per unit mass of fluid is directly proportional to the average transmittance, while it is inversely proportional to the beam spread. The rate of dissipation of the mean square temperature is inversely proportional to the average transmittance and directly proportional to the beam spread. When the temperature-induced optical turbulence is dominant, the average transmittance almost never decreases. However, the salinity-induced optical turbulence sharply reduces the average transmittance and increases the beam spread of the partially coherent flat-topped beam in underwater turbulence. When the off-axis parameter becomes larger, average transmittance decreases. (C) 2019 Optical Society of America
Physical optics theory for the diffraction of waves by impedance surfaces
(Optical Soc Amer, 2011) Umul, Yusuf Ziya; Umul, Yusuf Ziya; 42699
The solution of the scattering problem of waves by a half-screen with equal face impedances, which was introduced by Malyughinetz, is transformed into a physical optics integral by using the inverse edge point method. The obtained integral is applied to the diffraction problem of plane waves by an impedance truncated circular cylinder and the scattered waves are derived asymptotically. The results are examined numerically. (C) 2011 Optical Society of America

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