WoS İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8653

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A Modification Fractional Variational Iteration Method For Solving Non-Linear Gas Dynamic and Coupled Kdv Equations Involving Local Fractional Operators
(Vinca inst Nuclear Sci, 2018) Baleanu, Dumitru; Baleanu, Dumitru; Jassim, Hassan Kamil; Khan, Hasib; 56389
In this paper, we apply a new technique, namely local fractional variational iteration transform method on homogeneous/non-homogeneous non-linear gas dynamic and coupled KdV equations to obtain the analytical approximate solutions. The iteration procedure is based on local fractional derivative and integral operators. This method is the combination of the local fractional Laplace transform and variational iteration method. The method in general is easy to implement and yields good results. Illustrative examples are included to demonstrate the validity and applicability of the new technique.
A new application of chemometric techniques to HPLC data for the simultaneous analysis of a two-component mixture
(Taylor & Francis inc, 2005) Dinç, E; Baleanu, Dumitru; Üstündag, Ö; Özdemir, A; Baleanu, D; 56389
A new chemometric approach using high performance liquid chromatography (HPLC) with photodiode array (PDA) detection was developed and applied to the simultaneous determination of enalapril maleate (EA) and hydrochlorothiazide (HCT) in tablets. Chernometric calibration techniques, classical least squares (CLS), principle component regression (PCR), and partial least squares (PLS) were subjected to the peak area at multiwavelength PDA detector responses. The combination of HPLC and chernometric calibration techniques was called HPLC-CLS, HPLC-PCR, and HPLC-PLS. For comparison purposes, the HPLC method called classical HPLC method was used for the confirmation of the results obtained from combined HPLC-chemometric calibration techniques. A good chromatographic separation between two drugs and internal standard (IS) was achieved using a Waters Symmetry (R) C 18 Column 5 mu m 4.6 x 250 mm and a mobile phase consisting of 0.2M acetate buffer and acetonitrile (v/v, 60:40). The multiwavelength PDA detection was done at 230 (A), 240 (B), 250 (C), 250 (D), 240 (E) nm wavelengths, and peak area was recorded for the concentration set in the mobile phase. Three HPLC-chemometric calibrations and a classical-HPLC method were tested by analyzing the synthetic mixture of EA and HCT in the presence of losartan potassium (IS). The proposed methods were applied to real samples containing the present two drugs. The obtained results were statistically compared with each other.
A New Fractional Model For Convective Straight Fins With Temperature-Dependent Thermal Conductivity
(Vinca inst Nuclear Sci, 2018) Kumar, Devendra; Baleanu, Dumitru; Singh, Jagdev; Baleanu, Dumitru; 56389
The key aim of this work is to present a new non-integer model for convective straight fins with temperature-dependent thermal conductivity associated with Caputo-Fabrizio fractional derivative. The fractional energy balance equation is solved by using homotopy perturbation method coupled with Laplace transform method. The efficiency of straight fin has been derived in terms of thermo-geometric fin parameter. The numerical results derived by the application of suggested scheme are demonstrated graphically. The subsequent correlation equations are very helpful for thermal design scientists and engineers to design straight fins having temperature-dependent thermal conductivity.
Analysis of flat-topped Gaussian vortex beam scintillation properties in atmospheric turbulence
(Spie-soc Photo-optical instrumentation Engineers, 2019) Elmabruk, Kholoud; Eyyuboglu, Halil T.
We analyze the scintillation properties of a flat-topped Gaussian vortex beam propagating in a weakly turbulent atmosphere. We utilize a random phase screen model to perform this analysis. We evaluate the scintillation against the changes of topological charge, beam order, operating wavelength, receiver aperture side length, and source size parameters. The results show that using a flat-topped Gaussian vortex beam with a high topological charge causes a reduction in scintillation. Increasing the receiver aperture side length reduces scintillation level. As the source size increases, scintillation decreases. Our results also indicate that a flat-topped Gaussian vortex beam with high topological charges has less scintillation than the fundamental Gaussian beam. We believe that our findings will be useful in improving the performance of next-generation optical communication links and networks. (C) 2019 Society of Photo-Optical Instrumentation Engineers (SPIE)
Angle-of-arrival fluctuations for general-type beams
(Spie-soc Photo-optical instrumentation Engineers, 2007) Eyyuboglu, Halil T.; Baykal, Yahya; 7688; 7812
Starting with the recently introduced phase correlation function of a general-type beam, the angle-of-arrival fluctuations are derived and evaluated in atmospheric turbulence for lowest-order Gaussian, cos-Gaussian, cosh-Gaussian, annular, and flat-topped beams. Our motivation is to examine the improvement in the performance of optical atmospheric links when such beams are employed. For these beams, the dependence of the angle-of-arrival fluctuations on the propagation length, displacement and focusing parameters, source size, inner and outer scales of turbulence, and receiver radius is investigated. It is found that in the majority of the cases examined, the angle- of- arrival fluctuations remain small and hence are not expected to adversely affect the operation of free-space atmospheric links. It is observed that amongst the beams considered, the cos-Gaussian beam offers the least amount of angle-of-arrival fluctuations, while the worst behavior is exhibited by the cosh-Gaussian beam. This situation is reversed, however, if focused beams are used. (C) 2007 Society of Photo-Optical Instrumentation Engineers.
Approximate Controllability of Second-Order Nonlocal Impulsive Functional Integro-Differential Systems in Banach Spaces
(Korean Mathematical Soc, 2018) Baleanu, Dumitru; Baleanu, Dumitru; Arjunan, Mani Mallika; Nagaraj, Mahalingam; Suganya, Selvaraj; 56389
This manuscript is involved with a category of second-order impulsive functional integro-differential equations with nonlocal conditions in Banach spaces. Sufficient conditions for existence and approximate controllability of mild solutions are acquired by making use of the theory of cosine family, Banach contraction principle and Leray-Schauder nonlinear alternative fixed point theorem. An illustration is additionally furnished to prove the attained principles.
Automorphisms of braid groups on closed surfaces which are not S-2, T-2, P-2 or the Klein bottle
(World Scientific Publ Co Pte Ltd, 2006) Zhang, Ping
Consider a surface braid group of n strings as a subgroup of the isotopy group of homeomorphisms of the surface permuting n fixed distinguished points. Each automorphism of the surface braid group (respectively, of the special surface braid group) is shown to be a conjugate action on the braid group (respectively, on the special braid group) induced by a homeomorphism of the underlying surface if the closed surface, either orientable or non-orientable, is of negative Euler characteristic. In other words, the group of automorphisms of such a surface braid group is isomorphic to the extended mapping class group of the surface with n punctures, while the outer automorphism group of the surface braid group is isomorphic to the extended mapping class group of the closed surface itself.
Boride Layer Growth Kinetics of Aisi H13 Steel Borided With Nano-Sized Powders
(Polska Akad Nauk, Polish Acad Sciences, inst Metall & Mater Sci Pas, 2018) Karakaş, Mustafa Serdar; Karakas, M. S.; Gunen, A.; Yılmaz, Emre; Kanca, E.; Yilmaz, E.
Growth kinetics of boride layers in AISI H13 steel was investigated using the pack bonding method at temperatures of 1073, 1173 and 1273 K (800 degrees C, 900 degrees C and 1000 degrees C) for periods of 2, 4 and 6 h with nano-sized boron (NB) and micron-sized Ekabor II powders as bonding agents. The total thickness of the boride layer (including both FeB and Fe2B) after boriding at 1273 K (1000 degrees C) for 6 h was 103.8 gm and 96.5 mu m for the NB and Ekabor II specimens, respectively. X-ray diffraction analysis of the boride layers on the surfaces borided with NB and Ekabor II revealed the presence of FeB and Fe2B phases with sawtooth morphology. The FeB/Fe2B volume ratio was higher in the specimens borided with NB. The thickness of the boride layer (FeB + Fe2B) increased with the increasing boriding temperature and time. The FeB layer in the NB specimen displayed a (002) preferred orientation.
Chemometric approach to simultaneous chromatographic determination of paracetamol and chlorzoxazone in tablets and spiked human plasma
(Taylor & Francis inc, 2006) Dinç, E; Baleanu, Dumitru; Ozdemir, A; Aksoy, H; Baleanu, D; 6981; 26096
New chemometric approaches were introduced into the high performance liquid chromatographic (HPLC) determination of chlorzoxazone (CZX) and paracetamol (PAR) in the tablets and spiked human plasma. These chemometric approaches contain the application of classical least squares (CLS), principle component regression (PCR), and partial least squares (PLS) calibrations to the multiwavelength HPLC peak area obtained by plotting the chromatograms at the five wavelengths. The multichromatograms were obtained by using the photodiode array detector at 225 (A), 240 (B), 255 (C), 270 (D), and 285 (E) nm. The algorithms of CLS, PCR, and PLS were applied to the multichromatogram data to construct the HPLC-CLS, HPLC-PCR, and HPLC-PLS calibrations. A mixture of acetonitrile and 0.1 M ammonium carbonate (60:40, v/v) on a Waters Symmetry (R) trademark C18 Column 5 mu m 4.6 x 250 mm at a flow rate of 0.8 mL/min was used as a mobile phase to separate and determine CZX and PAR in samples. Hydrochlorothiazide (IS) was used as an internal standard in this chromatographic separation. The HPLC chemometric calibrations were successfully applied to the quantitative analysis of the investigated drugs in commercial pharmaceutical preparation and spiked human plasma samples with high precision and accuracy.
Classification of Linked Data Sources Using Semantic Scoring
(Ieice-inst Electronics information Communication Engineers, 2018) Yumusak, Semih; Doğdu, Erdoğan; Dogdu, Erdogan; Kodaz, Halife; 142876
Linked data sets are created using semantic Web technologies and they are usually big and the number of such datasets is growing. The query execution is therefore costly, and knowing the content of data in such datasets should help in targeted querying. Our aim in this paper is to classify linked data sets by their knowledge content. Earlier projects such as LOD Cloud, LODStats, and SPARQLES analyze linked data sources in terms of content, availability and infrastructure. In these projects, linked data sets are classified and tagged principally using VoID vocabulary and analyzed according to their content, availability and infrastructure. Although all linked data sources listed in these projects appear to be classified or tagged, there are a limited number of studies on automated tagging and classification of newly arriving linked data sets. Here, we focus on automated classification of linked data sets using semantic scoring methods. We have collected the SPARQL endpoints of 1,328 unique linked datasets from Datahub, LOD Cloud, LODStats, SPARQLES, and SpEnD projects. We have then queried textual descriptions of resources in these data sets using their rdfs: comment and rdfs: label property values. We analyzed these texts in a similar manner with document analysis techniques by assuming every SPARQL endpoint as a separate document. In this regard, we have used WordNet semantic relations library combined with an adapted term frequency-inverted document frequency (tfidf) analysis on the words and their semantic neighbours. In WordNet database, we have extracted information about comment/label objects in linked data sources by using hypernym, hyponym, homonym, meronym, region, topic and usage semantic relations. We obtained some significant results on hypernym and topic semantic relations; we can find words that identify data sets and this can be used in automatic classification and tagging of linked data sources. By using these words, we experimented different classifiers with different scoring methods, which results in better classification accuracy results.
Collisionless fragmentation of non-rotating Ni-n (n=4-14) clusters: a molecular dynamics study
(Iop Publishing Ltd, 2003) Avci, H; Çivi, M; Güvenç, ZB; Jellinek, J
Collisionless fragmentation of non-rotating Ni-n (n = 4-14) clusters is studied using micro-canonical molecular dynamics (MD) computer simulations. The clusters are modelled by an embedded-atom potential energy surface. The distributions of the channel-specific fragmentation probabilities, and the global and channel-specific fragmentation rate constants are computed and analysed as functions of the internal energy and size of the clusters. The trends derived from the dynamical calculations are compared to the fragmentation energy patterns, those of the Rice-Ramsperger-Kassel (RRK) and statistical approaches. The rate constants are an order of magnitude smaller for the RRK model than with both the MD and transition-state theory approaches. The results are also compared with the other multi-channel fragmentation works.
Continuous wavelet transform and chemometric methods for quantitative resolution of a binary mixture of quinapril and hydrochlorothiazide in tablets
(Soc Brasileira Quimica, 2007) Dinc, Erdal; Baleanu, Dumitru; Baleanu, Dumitru; 56389
Quantitative resolution of the quinapril and hydrochlorothiazide mixture in tablets was achieved by using continuous wavelet transform and chemometric methods. In the case of the continuous wavelet transform, various continuous wavelet families were tested in order to find the optimum point of the wavelet signal processing technique. The Mexican hat wavelet function was reported to be the optimal one. The Mexican hat wavelet function was applied to the absorption spectra of quinapril and hydrochlorothiazide in the spectral range of 200-320 nm for standard series of drugs in the concentration range of 4.0-20.0 mu g mL(-1) quinapril and 2.5-12.5 mu g mL(-1) hydrochlorothiazide. The calibration functions for quinapril at 230.6 nm and for hydrochlorothiazide at 271.1 nm were calculated based on the relationship between the measurements of continuous wavelet signals and their concentrations. According to the chemometric approach, partial least squares and principal component regression calibrations were constructed by a training set of 21 mixtures, containing two drugs and their corresponding absorbance data, in the wavelength range of 205-290 nm. All proposed methods were validated by the independent analysis of the synthetic mixtures and by the standard addition technique. The application of the methods indicated that their selectivity and the sensitivity were satisfactory. The investigated methods were successfully applied to tablet analysis.
Discrete variational principles for Lagrangians linear in velocities
(Pergamon-elsevier Science Ltd, 2007) Jarad, Fahd; Jarad, Fahd; Baleanu, Dumitru; Baleanu, Dumitru
The discrete Hamiltonian formulation of Lagrangian linear in velocities is investigated and the equivalence of Hamilton and Euler-Lagrange equations is obtained. The role of Lagrange multipliers is discussed within discrete Lagrangian and Hamiltonian formulations for some systems with constraints. Three illustrative examples are investigated in details.
Effect of anisotropy on intensity fluctuations in oceanic turbulence
(Taylor & Francis Ltd, 2018) Baykal, Yahya; 7812
For an optical spherical wave propagating in an oceanic turbulent medium, the effect of anisotropy on the received intensity fluctuations is investigated. For different anisotropy factors, the variations of the scintillation index vs. the ratio that determines the relative strength of temperature and salinity in the index fluctuations, the rate of dissipation of the mean squared temperature, the rate of dissipation of the turbulent kinetic energy, viscosity, link length and the wavelength are plotted. It is found that, for all the oceanic turbulence and the link parameters of interest, as the medium becomes more anisotropic, the intensity of the optical spherical wave fluctuates less. It is concluded that the performance of an optical wireless communication systems (OWCS) operating in anisotropic oceanic turbulence is better than the performance of OWCS operating in isotropic oceanic turbulence.
Effect of source spatial partial coherence on the angle-of-arrival fluctuations for free-space optics links
(Spie-soc Photo-optical instrumentation Engineers, 2006) Baykal, Yahya; Eyyuboglu, Halil Tanyer; 7812; 7688
The dependence of angle-of-arrival fluctuations on source coherence for free-space optics links in a turbulent atmosphere is examined. A monochromatic beam is taken, and the variation of the angle-of-arrival fluctuations for a spatially partially coherent source is investigated. Results are obtained for the currently used free-space optics links, which use infrared wavelengths of 0.85 and 1.55 mu m with link lengths of 3 and 5 km. The angle-of-arrival fluctuations are calculated and plotted against normalized source size and inner and outer scales of turbulence. It is observed that the angle-of-arrival fluctuations show behavior that is essentially independent of the degree of source partial coherence. In fact, as the source size increases, this dependence seems to almost disappear. It is further observed that mean square angle-of-arrival fluctuations become larger at greater propagation distances, at smaller inner scales of turbulence, and at larger outer scales of turbulence. However, the numerical values of the angle-of-arrival fluctuations found for all cases are not expected to degrade substantially the performance of a practical optical receiver having a field of view in the order of several milliradians. Our results presented here are compared with the existing theoretical and experimental work, and the range of applicability of our formulation is discussed. (C) 2006 Society of Photo-Optical Instrumentation Engineers.
Experimental study on the sensitivity of autocalibration to projective camera model parameters
(Spie-soc Photo-optical instrumentation Engineers, 2006) Hassanpour, Reza; Hassanpour, Reza; Atalay, Volkan; 48646
Existing methods of 3-D object modeling and recovering 3-D data from uncalibrated 2-D images are subject to errors introduced by assumptions about camera parameters and mismatches in finding point pairs in the images. In this study, we experimentally evaluate the effect of each of these assumptions together with the inaccuracy in the measurements in the images. Sensitivity of reconstruction errors to inaccuracies in the estimation of camera parameters and mismatches due to noise in input data is measured using a linear and two nonlinear autocalibration methods for a projective camera. Our experimental results show that some assumptions such as a vanishing skew can be safely made; however, other parameters such as principal point location are quite sensitive to wrong assumptions. (c) 2006 Society of Photo-Optical Instrumentation Engineers.
Fast decoding of polar codes using tree structure
(inst Engineering Technology-iet, 2019) Andi, Alia A.; Gazi, Orhan; Gazi, Orhan; 102896
In this study, the authors first propose a tree structure for the successive cancelation (SC) decoding of polar codes. The proposed structure is easy to implement in hardware and suitable for parallel processing operations. Next, using the proposed tree structure, they propose a technique for the fast decoding of polar codes. With the proposed method, it is possible to decode all the information bits simultaneously at the same time, i.e. in parallel. Lastly, they introduce an improved version of the proposed high-speed decoding algorithm. The proposed high-speed decoding approach and its improved version are simulated on the computer environment and their bit error rate performances are compared to the performance of the classical SC method.
Filter design for small target detection on infrared imagery using normalized-cross-correlation layer
(Tubitak Scientific & Technological Research Council Turkey, 2020) Demir, H. Seckin; Akagunduz, Erdem; 233834
In this paper, we introduce a machine learning approach to the problem of infrared small target detection filter design. For this purpose, similar to a convolutional layer of a neural network, the normalized-cross-correlational (NCC) layer, which we utilize for designing a target detection/recognition filter bank, is proposed. By employing the NCC layer in a neural network structure, we introduce a framework, in which supervised training is used to calculate the optimal filter shape and the optimum number of filters required for a specific target detection/recognition task on infrared images. We also propose the mean-absolute-deviation NCC (MAD-NCC) layer, an efficient implementation of the proposed NCC layer, designed especially for FPGA systems, in which square root operations are avoided for real-time computation. As a case study we work on dim-target detection on midwave infrared imagery and obtain the filters that can discriminate a dim target from various types of background clutter, specific to our operational concept.
Flow and Turbulence Structure in A Baffle-Brush Fish Pass
(Ice Publishing, 2018) Kucukali, Serhat; Küçükali, Serhat; Hassinger, Reinhard; 20413
The flow an d turbulence characteristics of a new baffle-brush type fish pass were investigated experimentally in a 2 m wide rectangular flume with a bed slope of 4% and Reynolds and Froude numbers in the range 5 x 10(4)-2.8 x 10(5) and 0.17-0.23, respectively. The baffle-brush fishway combines the properties of a baffle (Larinier) fish pass with the features of the brush-furnished fishway. The baffle-brush fish pass ensures continuous low-and high-velocity migration corridors for both strong (e.g. salmon) and weak swimming (e.g. river lamprey) fish, with negligible flow accelerations (i.e. quasi-uniform conditions). The turbulent kinetic energy (TKE) takes its maximum value near the centre of the baffle zone and decays towards the brush zone. The effects of the Reynolds number (Re) on the resultant velocity and TKE distributions were also investigated. For Re = 2 x 10(5), the TKE was in the range 0.05-0.21 m(2)/s(2) with an average value of 0.11 m(2)/s(2) in the baffle section, whereas it ranged between 0.007 and 0.04 m(2)/s(2) with an average value of 0.02 m(2)/s(2) in the brush section. In the proposed fish pass there is no need to build resting pools.
Grey and black optical solitary waves, and modulation instability analysis to the perturbed nonlinear Schrodinger equation with Kerr law nonlinearity
(Taylor & Francis Ltd, 2019) Inc, Mustafa; Baleanu, Dumitru; Aliyu, Aliyu Isa; Yusuf, Abdullahi; Baleanu, Dumitru; 56389
This paper addresses the nonlinear Schrodinger equation (NLSE) with Kerr law nonlinearity and perturbation terms in optical fibre. A class of grey and black optical solitary wave solutions of this equation are retrieved by adopting an appropriate solitary wave ansatz solution. These types of solitary waves play a vital role in understanding various physical phenomena in nonlinear systems. This lead to a constraint condition on the solitary wave parameters which must hold for the solitary waves to exist. Moreover, the modulation instability (MI) analysis of the model is studied by employing the concept of linear-stability analysis (LSA) and the MI gain spectrum is got. Physical interpretations of the acquired results are demonstrated. It is hoped that the results reported in this paper can enrich the nonlinear dynamical behaviours of the equation.

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