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Hartree-Fock-Roothaan Calculations for Ground States of Some Atoms Using Minimal Basis Sets of Integer and Noninteger n-STOs

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Chinese Journal of Chemistry 2004年第11期22卷 1262-1266页

作者： GüMü■ sedat ZSO■AN Telhat Department of Physics Amasya Education Faculty Ondokuz Mayis University 05189 Amasya TURKEYDepartment of Physics Amasya Education Faculty Ondokuz Mayis University 05189 Amasya TURKEY

Hartree-Fock-Roothaan (HFR) calculations for ground states of some atoms, i.e. He, Be, Ne, Ar, and Kr have been performed using minimal basis sets of Slater type orbitals (STOs) with integer and noninteger principal quan-tum numbers (integer n-STOs and noninteger n-STOs). The obtained total energies for these atoms using minimal basis sets of integer n-STOs are in good agreement with those in the previous literature. On the other hand, for the case of minimal basis sets of noninteger n-STOs, although the calculated total energies of these atoms agree well with the results in literature, some striking results have been obtained for atoms Ar and Kr. Our computational re-sults for the energies of atoms Ar and Kr are slightly better than those in literature, by amount of 0.00222 and 0.000054 a.u., respectively. The improvement in the energies of atoms Ar and Kr may result from the efficient cal-culations of one-center two-electron integrals over noninteger n-STOs. For some atomic ions in their ground state, HFR calculations have been carried out using minimal basis sets of noninteger n-STOs. The obtained total energies for these atomic ions are substantially lower than those available in literature.

关键词： Hartree-Fock-Roothaan Slater type orbital

Transient Temperature Analysis of Slab in Erdemir

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Journal of Iron and Steel Research(International) 2008年第2期15卷 43-45页

作者： nal amdali Murat Tun sedat Sisbot Faculty of Engineering and Architecture Abant Izzet Baysal University Engineering Faculty Yeditepe University

A transient thermal model was developed for slab furnaces in Eregli Iron and Steel Works （Erdemir） in Turkey and the model was solved using the FlexPDE computer program. This program uses the finite element method. Program codes were written to solve the temperature distribution of slabs that are put into furnace at 25 ℃ and removed at about 1 250℃. To obtain the optimum slab exit temperature variation, the necessary air temperature inside the furnace was calculated to be 1 390℃. The slab temperature versus time and the temperature variation inside the slab were depicted.

关键词： Erdemir finite element method industrial system slab slab furnace temperature analysis

Clinical presentation and management of Fasciola hepatica infection:Single-center experience

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World Journal of Gastroenterology 2011年第44期17卷 4899-4904页

作者： Muhsin Kaya Remzi Bestas sedat Cetin Department of Gastroenterology Dicle University School of Medicine Department of Internal Medicine Dicle University School of Medicine

AIM:To identify the characteristic clinical,laboratory and radiological findings and response to treatment in patients with ***:Patients who were diagnosed with Fasciola hepatica infection were included in this prospective *** clinical,laboratory and radiological findings were *** patients were followed until a complete response was achieved or for 6 mo after treatment ***:Fasciola hepatica infection was diagnosed in 30 patients(24 females;mean age:42.6 years) between January 2008 and February ***(73%) patients had hepatic phase fascioliasis,5 patients had biliary phase,and 3 patients had biliary phase associated with acute *** the 8 patients with biliary phase fascioliasis,2 patients displayed features that overlapped with both hepatic and biliary *** pain and right upper abdominal tenderness were the most prominent signs and symptoms in all *** was the most prominent laboratory abnormality in both patients with hepatic and biliary phase(100% and 50%,respectively).Multiple nodular lesions like micro-abscesses on abdominal computerized tomography were the main radiological findings in patients with hepatic *** linear filling defects in the distal choledochus were the main endoscopic retrograde cholangiopancreatography(ERCP) findings in patients with biliary *** with hepatic phase were treated with triclabendazole alone,and patients with biliary phase were treated with triclabendazole and had live Fasciola hepatica extracted from the bile ducts during ***:Fasciola hepatica infection should be considered in the differential diagnosis of patients with hepatic or biliary disease and/or acute pancreatitis associated with eosinophilia.

关键词：肝片吸虫感染临床表现嗜酸性粒细胞急性胰腺炎管理鉴别诊断肝片形吸虫实验室

Analysis of the changes in forest ecosystem functions,structure and composition in the Black Sea region of Turkey

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Journal of Forestry Research 2017年第2期28卷 329-342页

作者： sedat Keles Idris Durusoy Günay Cakir Faculty of Forestry Cankin Karatekin University18100 CankinTurkey Faculty of Forestry Duzce University81620 DuzceTurkey Department of Forestry and Environmental Science Graduate School of Natural and Applied SciencesGumushane University29100 GumushaneTurkey

We used geographical information system to analyze changes in forest ecosystem functions, structure and composition in a typical department of forest management area consisting of four forest management planning units in Turkey. To assess these effects over a 25 year period we compiled data from three forest management plans that were made in 1986, 2001 and 2011. Temporal changes in forest ecosystem functions were estimated based on the three pillars of forest sustainability： economics, ecology and socio-culture. We assessed a few indicators such as land-use and forest cover, forest types,tree species, development stage, stand age classes, crown closure, growing stock and its increment, and timber biomass. The results of the case study suggested a shift in forest values away from economic values toward ecological and socio-cultural values over last two planning periods. Forest ecosystem structure improved, due mainly to increasing forest area, decreasing non-forest areas（especially in settlement and agricultural areas）, forestation on forest openings, rehabilitation of degraded forests, conversion of even-aged forests to uneven-aged forests and conversion of coppice forests to high forests with greater growing stock increments. There were also favorable changes in forest management planning approaches.

关键词： ecosystem forests timber stand biomass stock favorable closure rehabilitation Turkey

Evaluation of mixed mode-Ⅰ/Ⅱ criteria for fatigue crack propagation using experiments and modeling

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Chinese Journal of Aeronautics 2018年第7期31卷 1525-1534页

作者： Oguzhan DEMIR Ali O.AYHAN sedat IRIC Hüseyin LEKESIZ Department of Mechanical Engineering Sakarya University Department of Mechanical Engineering Bilecik S?eyh Edebali University Department of Mechanical Engineering Bursa Technical University

In this study, in-plane mixed mode-Ⅰ/Ⅱ fatigue crack growth simulations and experiments are performed for the Al 7075-T651 aluminum alloy which is widely used in the aerospace industry. Tests are carried out under different mode mixity ratios to evaluate the applicability of a fracture criterion developed in a previous study to mixed mode-Ⅰ/Ⅱ fatigue crack growth *** obtained from the analyses and experiments are compared with existing and developed criteria in terms of crack growth lives. Compact Tension Shear（CTS） specimens, which enable mixed mode loading with loading devices under different loading angles, are used in the simulations and experiments. In an effort to model and simulate the actual conditions in the experiments, crack surfaces of fractured specimens are scanned, crack paths are modeled exactly, and contacts are defined between the contact surfaces of a specimen and the loading device for each crack propagation step in the analyses. Having computed the mixed mode stress intensity factors from the numerical analyses, propagation life cycles are predicted by existing and the developed mixed mode-Ⅰ/Ⅱ criteria and then compared with experimental results.

关键词： Crack propagation Fatigue crack growth simulation Fatigue crack growth test Fracture mechanics Mixed mode-Ⅰ/Ⅱ

Electrical and dielectric properties of Al/p-Si and Al/perylene/p-Si type diodes in a wide frequency range

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Chinese Physics B 2014年第1期23卷 519-524页

作者： Ahmet Kaya sedat Zeyrek Sait Eren San Şmsettin Altındal Opticianry Department Vocational School of Medical Sciences Turgut Ozal University Ankara 06370 Turkey Physics Department Faculty Sciences Dumlupınar University Kütahya 43000 Turkey Physics Department Gebze Institute of Technology Kocaeli 41400 Turkey Physics Department Faculty of Sciences Gazi University Ankara 06500 Turkey

The perylene （C20H12） layer effect on the electrical and dielectric properties of Al/p-Si （MS） and Al/perylene/p-Si （MPS） diodes have been investigated and compared in the frequency range of 0.7 kHz-2 MHz. Experimental results show that C-V characteristics give an anomalous peak for two structures at low frequencies due to interface states （Nss） and series resistance （Rs）. The increases in C and G/o3 at low frequencies confirm that the charges at interface can easily follow an ac signal and yield excess capacitance and conductance. The frequency-dependent dielectric constant （er） and dielectric loss （e＇） are subtracted using C and G/co data at 1.5 V. The eI and e＂ values are found to be strongly dependent on frequency and voltage, and their large values at low frequencies can be attributed to the excess polarization coming from charges at traps. Plots of ln（o＇ac）-ln（w） for two structures have two linear regions, with slopes of 0.369 and 1.166 for MS, and of 0.077 and 1.061 for MPS, respectively. From the C 2-V characteristics, the doping acceptor atom concentration （NA） and barrier height （,~） for Schottky barrier diodes （SBDs） 1.303 ~ 1015 cm-3, and 1.10 and I. 13 eV, respectively. of MS and MPS types are also obtained to be 1.484 ~ 1015

关键词： organic-inorganic based Schottky diodes perylene (C20H12) interfacial layer electrical and di-electric properties frequency and voltage dependence

Artificial neural network models predicting the leaf area index:a case study in pure even-aged Crimean pine forests from Turkey

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Forest Ecosystems 2018年第4期5卷 400-411页

作者： ilker Ercanli Alkan Gunlu Muammer Senyurt sedat Keles Faculty of Forestry Cankin Karatekin University18200 CankiriTurkey

Background: Leaf Area Index(LAI) is an important parameter used in monitoring and modeling of forest ecosystems. The aim of this study was to evaluate performance of the artificial neural network(ANN) models to predict the LAI by comparing the regression analysis models as the classical method in these pure and even-aged Crimean pine forest ***: One hundred eight temporary sample plots were collected from Crimean pine forest stands to estimate stand parameters. Each sample plot was imaged with hemispherical photographs to detect the LAI. The partial correlation analysis was used to assess the relationships between the stand LAI values and stand parameters, and the multivariate linear regression analysis was used to predict the LAI from stand parameters. Different artificial neural network models comprising different number of neuron and transfer functions were trained and used to predict the LAI of forest ***: The correlation coefficients between LAI and stand parameters(stand number of trees, basal area, the quadratic mean diameter, stand density and stand age) were significant at the level of 0.01. The stand age, number of trees, site index, and basal area were independent parameters in the most successful regression model predicted LAI values using stand parameters(R_(adj)~2=0.5431). As corresponding method to predict the interactions between the stand LAI values and stand parameters, the neural network architecture based on the RBF 4-19-1 with Gaussian activation function in hidden layer and the identity activation function in output layer performed better in predicting LAI(SSE(12.1040), MSE(0.1223), RMSE(0.3497), AIC(0.1040), BIC(-77.7310) and R^2(0.6392)) compared to the other studied ***: The ANN outperformed the multivariate regression techniques in predicting LAI from stand parameters. The ANN models, developed in this study, may aid in making forest management planning in study forest stands.

关键词： Leaf area index Multivariate linear regression model Artificial neural network modeling Crimean pine Stand parameters

A Parallel Boundary Element Formulation for Tracking Multiple Particle Trajectories in Stoke’s Flow for Microfluidic Applications

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Computer Modeling in Engineering & Sciences 2015年第3期104卷 227-249页

作者： Z.Karakaya B.Baranoglu B.Çetin A.Yazici Computer Engng.Dept. Atilim UniversityTurkey Manufacturing Engng.Dept. Atilim UniversityTurkey Microfluidics & Lab-on-a-chip Research Group Mech.Engng.Dept.Bilkent UniversityTurkey Software Engng.Dept. Atilim UniversityTurkey

A new formulation for tracking multiple particles in slow viscous flow for microfluidic applications is *** method employs the manipulation of the boundary element matrices so that finally a system of equations is obtained relating the rigid body velocities of the particle to the forces applied on the *** formulation is specially designed for particle trajectory tracking and involves successive matrix multiplications for which SMP(Symmetric multiprocessing)parallelisation is *** is observed that present formulation offers an efficient numerical model to be used for particle tracking and can easily be extended for multiphysics simulations in which several physics involved.

关键词： Boundary Element Method particle tracking Stoke's flow parallel computing

Estimation of Tsunami Run-up Height by Three Artificial Neural Network Methods

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China Ocean Engineering 2009年第1期23卷 85-94页

作者： Nuray GEDIK Emel IRTEM H.Kerem CIGIZOGLU M.sedat KABDASLI Department of Civil Engineering Balikesir University Division of Hydraulics Civil Engineering FacultyIstanbul Technical University

Tsunami ran-up height is a significant parameter for dimensions of coastal structures. In the present study, tsunami run-up heights are estimated by three different Artificial Neural Network （ANN） models, i.e. Feed Forward Back Propagation （FFBP）, Radial Basis Functions （RBF） and Generalized Regression Neural Network （GRNN）. As the input for the ANN configuration, the wave height （H） values are employed. It is shown that the tsunami ran-up height values are closely approximated with all of the applied ANN methods. The ANN estimations are slightly superior to those of the empirical equation. It can be seen that the ANN applications are especially significant in the absence of adequate number of laboratory experiments. The results also prove that the available experiment data set can be extended with ANN simulations. This may be helpful to decrease the burden of the experimental studies and to supply results for comparisons.

关键词： tsanami run-up height artificial neural network methods experiments