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Journal of Earth Science 2014年第2期25卷 348-356页

作者： Ali Erden Babacan Kenan Gelisli hakan Ersoy Karadeniz Technical University Department of Geophysics Engineering

Economic development, industrialization and dense population in Trabzon City have caused residential construction to increase by 300% in the last decade. The settlement area is moun- tainous and covered with heavy vegetation. Thus, the steep-sided topography and heavy precipita- tion means floods and landslides are common and in areas with little flat land. Since the mass movements in some parts of city create an enormous danger for buildings, site selection for residen- tial areas becomes increasingly important. This paper describes geotechnical and seismic properties of Tertiary volcanic rock and establishes the link between these units and construction. In this study, refraction tomography and multichannel analysis surface wave methods were applied in order to seek the best construction site in the residential area. The results of the geophysical study were com- pared with the borehole applications. A series of geomechnical tests were carried out on the core samples. Following that, statistical correlations were conducted by regression analysis to evaluate re- lationships between measured parameters. Rock Quality Designation and weathering degree were also determined. The methodology defined in this investigation proves to be an appropriate ap- proach to determine geotechnical properties of the foundation rocks and soils and a proper guide on future geotechnical studies for other cities.

关键词： Trabzon City Turkey refraction tomography MASW ultrasonic geotechnical.

Accidental Degeneracies in N dimensions for Potential Class αr^(2d-2)-βr^(d-2) via Asymptotic Iteration Method(AIM)

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Communications in Theoretical Physics 2017年第4期67卷 350-354页

作者： H.F.Kisoglu hakan Ciftci Department of Basic Sciences Faculty of MaritimeMersin University Physics Department Science FacultyGazi University

In mathematical physics the main goal of quantum mechanics is to obtain the energy spectrum of an atomic *** many practices,Schrodinger equation which is a second order and linear differential equation is solved to do this *** are many theoretic mathematical methods serving this *** use Asymptotic Iteration Method(AIM) to obtain the energy eigenvalues of Schrodinger equation in N-dimensional euclidean space for a potential class given as αr^(2d-2)-βr^(d-2).We also obtain a restriction on the eigenvalues that gives ***,we crosscheck the eigenvalues and degeneracies using the perturbation theory in the view of the AIM.

关键词： asymptotic iteration method perturbation method approximate solutions

Thermal management of nanoliquid forced convective flow over heated blocks in channel by using double elliptic porous objects

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Propulsion and Power Research 2021年第3期10卷 262-276页

作者： Fatih Selimefendigil hakan FÖztop Department of Mechanical Engineering Manisa Celal Bayar UniversityManisa45410Turkey Department of Mechanical Engineering Technology FacultyFõrat University23119Turkey

Effects of using nanoliquid and double porous elliptic objects on the flow separation and convective heat transfer control for flow over multiple heated blocks in channel are numerically investigated by using finite element ***,brick,blade and cylindrical shaped alumina particles are used in water up to solid volume fraction of 2%.Impacts of Reynolds number(50≤Re≤500),permeability of the porous ellipses(10^(-5)≤D_(a1)≤5×10^(-2) and 10^(-5)≤D_(a2)≤5×10^(-2)),aspect ratio of the ellipses(0.25≤AR_(1)≤1.5,0.25≤AR_(2)≤1.5),distance between the ellipses(0.2H≤sx≤1.6H)and distance of the first ellipse from inlet(-H≤mx≤H)on the hydro-thermal performance are *** highest performance improvement is obtained by using the cylindrical shaped particles in the base heat transfer fluid at the highest solid volume fraction and the amount of heat transfer enhancement are 33%and 40.5%for hot blocks while negligible pressure drop is *** the aspect ratio of the ellipses in the perpendicular direction to the flow,up to 25%and 30%heat transfer increment are obtained for hot block with slight rise of pressure ***,when varying the horizontal location of the porous ellipses in the channel and permeability of them,there is considerable rise of pressure *** of the average heat transfer from the hot blocks with varying permeability of the ellipses are obtained as 32%and 25%.Successful hydro-thermal performance estimation results are achieved by using artificial neural networks with feed-forward network architecture of 1 hidden layer and 17 neurons.

关键词： Thermal management Porous ellipses Finite element method Hydro-thermal performance Nanoliquid Nanoparticle shape

Behaviour and perception of parents on irrational use of antibiotics in children at primary care level:A cross-sectional study from Turkey

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Asian Pacific Journal of Tropical Medicine 2023年第6期16卷 253-260页

作者： Burak Mete Tarik Salcan hakan Demirhindi Department of Public Health Faculty of MedicineCukurova UniversityAdana01330Turkey

Objective:To investigate the perception of antibiotics,the frequency of inappropriate antibiotic use,and the factors that lead to inappropriate antibiotic use by parents who apply to primary healthcare ***:This cross-sectional study included 973 parents who applied to primary healthcare *** analyzed basic concepts related to antibiotics prescribed for their children,antibiotic administration,and antibiotic resistance,as well as parents'knowledge and attitudes towards antibiotic use,and their experiences,practices,and perceptions related to purchasing antibiotics without ***:In the past one year,78.9%of the parents gave antibiotics to their children at least once,and 39.1%gave antibiotics three or more *** of the participants(7.1%)reported having forced the physician to prescribe antibiotics and purchased antibiotics without a prescription(13.2%).The knowledge about antibiotics and awareness about antibiotic resistance were found to be more frequent;among parents who had university degrees,higher income levels,two or fewer children,social insurance and negative behaviours were lower in those who received information about antibiotics from healthcare *** probability of taking antibiotics without prescription was lower in that of with higher income level(OR 0.460;95%CI 0.219-0.965),and the probability of forcing antibiotic prescription was higher in those with 3 or more children(OR 6.94;95%CI 2.37-20.26).The score obtained from the awareness of antibiotic resistance sub-dimension was found to negatively affect the behavior of forcing antibiotic prescription(OR 0.852;95%CI 0.732-0.993)but the score obtained from the behaviour sub-dimension was positively affect this behaviour(OR 1.136;95%CI 1.011-1.276).Conclusions:Inappropriate antibiotic use appears to be a problem with negative perception,lack of knowledge and socioeconomic *** should be conducted to increase antibiotic knowledge in parents

关键词： Antibiotics Attitudes Social insurance Educational activities

Tribological behavior of CrN-coated Cr–Mo–V steels used as die materials

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International Journal of Minerals,Metallurgy and Materials 2017年第12期24卷 1394-1402页

作者： Gulsah Aktas Celik Seyda Polat S.hakan Atapek Kocaeli University Faculty of EngineeringDepartment of Metallurgical and Materials EngineeringUmuttepe Campus41380 KocaeliTurkey

DIN 1.2343 and 1.2367 steels are commonly used as die materials in aluminum extrusion, and single/duplex/multi-coatings enhance their surface properties. The design of an appropriate substrate/coating system is important for improving the tribological performance of these steels under service conditions because the load-carrying capacity of the system can be increased by decreasing the plastic deformation of the substrate. In this study, the tribological behavior of CrN-coated Cr–Mo–V steels(DIN 1.2343, 1.2367, and 1.2999 grades) was investigated using different setups and tribological pairs at room and elevated temperatures. The aim of this study was to reveal the wear resistance of a suggested system(1.2999/CrN) not yet studied and to understand both the wear and the failure characteristics of coated systems. The results showed that(i) among the steels studied, the DIN 1.2999 grade steel exhibited the lowest friction coefficient because it had the highest load-carrying capacity as a result of secondary hardening at elevated temperatures;(ii) at room temperature, both abrasive tracks and adhesive layers were observed on the worn surfaces; and(iii) a combination of chemical reactions and progressive oxidation caused aluminum adhesion on the worn surface, and the detachment of droplets and microcracking were the characteristic damage mechanisms at high temperatures.

关键词： Cr–Mo–V steels CrN coating aluminum extrusion tribological behavior

Optimization of Electrical Conductivity of SA-graphene Nanocomposites Using Response Surface Methodology

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Chemical Research in Chinese Universities 2022年第2期38卷 596-602页

作者： hakanŞAHAL Gülben TORĞUT Erdal CANPOLAT Vocational School of Tunceli Department of Food ProcessingMunzur UniversityTunceli 62000Turkey Vocational School of Tunceli Department of Chemistry and Chemical ProcessesMunzur UniversityTunceli 62000Turkey Department of Elementary Science Education Faculty of EducationFirat UniversityElazig 23119Turkey

Synthesis and characterization of 4-{(E)-[(5-bromo-2-hydroxyphenyl)methylidene]amino}-N-carbamimidoylbenzene-1-sulfonamide(SA) and its composites with graphene(SA-GF) were performed. Compound SA and SA-GF were characterized by FTIR and 1H NMR. The GF dispersion in the composites was analyzed by means of scanning electron microscopy(SEM) for morphology. Thermal properties of SA and nanocomposites were investigated using differential thermal analysis(DTA) and thermogravimetric analysis(TGA). The optimum electrical conductivity of the new sulfonamide-based Schiff base was determined to be 1.78×10–5 S/cm at a frequency of 9923 Hz, an applied voltage of –19 V, a mass fraction of 9.38% for graphene loading using a central composite design in the response surface methodology. The significance of the selected parameters(frequency, voltage and GF amount) in the model was determined by the analysis of variance(ANOVA). The results showed that frequency and graphene loading represent important model terms and have considerable effects on the conductivity of SA.

关键词： Schiff base Sulfonamide Graphene Conductivity Nanocomposite

Advanced exergy analysis of the turbojet engine main components considering mexogenous, endogenous, exegenous, avoidable and unavoidable exergy destructions

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Propulsion and Power Research 2022年第3期11卷 391-400页

作者： hakan Caliskan Selcuk Ekici Yasin Sohret Department of Mechanical Engineering Faculty of EngineeringUsak UniversityUsak64200Turkey Department of Aviation Igdir UniversityIgdir76000Turkey Department of Airframe and Powerplant Maintenance School of Civil AviationSuleyman Demirel UniversityIsparta32700Turkey

In this study, exergy dynamic and advanced exergy analyses are applied to theturbojet engine to assess its mexogenous, endogenous, exogenous, avoidable and unavoidableexergies under the environment conditions of 15 C temperature and 1 bar pressure. Themaximum exergy point in the turbojet engine is found for the combustor in which C11H23(Jet-A1) fuel is combusted with air, while the minimum one is determined for the aircompressor head where the free air enters. The combustion chamber has the maximum fuel,product and irreversibility rates and the air compressor has the minimum fuel and product ex-ergy values, while the minimum irreversibility is found for the turbine. Maximum improvementpotential rate is found for the combustion chamber (5141.27 kW), while minimum rate is deter-mined for the turbine of system (6.95 kW). Also, the turbine component has the highest exergyefficiency (97.20%) due to its expansion process, while combustion chamber component hasthe lowest exergy efficiency (55.39%) due to low efficient combustion process of the ***, the mexogenous exergy destructions from maximum to minimum are found for the combustion chamber, air compressor and gas turbine units, respectively. Considering exergydynamic analysis, the mexogenous exergy destruction rates of the combustion chamber, aircompressor and gas turbine are found as 184.4 kW, 103.97 kW and 9.99 kW, *** all results, the combustion chamber is the primer component to be handled for bet-ter efficiency and improvement.

关键词： Advanced exergy Efficiency Gas turbine Jet fuel Mexogenous Turbojet Thermodynamic analysis Aircraft

Design and simulation of a 1-GWp solar photovoltaic power station in Sudan

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Clean Energy 2021年第1期5卷 57-78页

作者： Sohaib Nasr Mohamed Abdalla hakanÖzcan Department of Mechanical Engineering Ondokuz Mayis UniversitesiSamsun 55139Turkey

Developing nations have a critical need to increase electricity *** has much unrealized potential for generating solar energy,particularly in the northern *** research study focuses on designing a 1-GW solar power station in northern Sudan using the PVsyst7.0 software *** determine the appropriate location for the solar-energy station,14 criteria were *** process is generic and suitable for use in any other *** method for conducting cash-flow estimates and return on investment is illustrated in the economic *** city of Dongola,the capital of the northern state,was selected because of its high annual irradiance on a horizontal surface at~2333.2 kWh/*** simulation results show that the annual optimum tilt angle of inclination for photovoltaic(PV)modules is 30°,the energy production is 1979259 MWh/yr and the average annual performance rate is *** addition,the electric power consumption per capita in Sudan is 269 kWh/yr,so the proposed solar power plant with 1979259 MWh/yr can provide energy to 7.4 million people per year annually and reduce carbon emissions by~18 million tons of carbon dioxide per *** calculations show that the levelized cost of electricity(LCOE)is$0.06/kWh,the discounted payback period is~11 years and the net present value is$*** a result,the proposed grid-connected PV solar plant is considered economically,technically and environmentally feasible in Sudan.

关键词： solar energy Sudan design simulation evaluation analytic hierarchy process photovoltaic

Development a Spectrophotometric of Fe(Ⅲ), Al(Ⅲ) and Cu(Ⅱ) Using Eriochrome Cyanine R Ligand and Assessment of the Obtained Data by Partial Least-Squares and Artificial Neural Network Method-Application to Natural Waters

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光谱学与光谱分析 2018年第8期38卷 2638-2644页

作者： A. hakan AKTAS Department of Chemistry Faculty of Science & Art Suleyman Demirel University Isparta 32260 Turkey

Simultaneous determination of heavy metal cations and accurate quantitative prediction of them are of great interest in analytical *** work has focused on a comprehensive comparison of partial least squares(PLS-1)and artificial neural networks(ANN)as two types of chemometric *** this purpose,aluminum,iron and copper were studied as three analytes whose UV-Vis absorption spectra highly overlap each *** with determined parameters(ligand concentration,pH,waiting times,the relationship between absorbance and concentration of metal ion effect and foreign ions)are provided and the optimum *** establishing the optimum conditions for Fe^(3+),Al^(3+) and Cu^(2+) containing mixtures spectrophotometric determinations and the data calibration method of least squares(PLS-1)regression,and artificial neural network(ANN)methods were *** methods are applied in a fast,simple,and the results are applicable.

关键词： UV-Vis spectrophotometry Partial least squares Artificial neural network Aluminum Iron Copper

Modeling of Reversibleγ/αTransformations of Low Carbon Steels in the Intercritical Temperature Range

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材料热处理学报 2004年第05B期25卷 702-705页

作者： Tamás RTl Imre FELDE hakan GR Budapest Polytechnic Budapest HungaryBay Zoltdn Institute for Materials Science and Technology Budapest HungaryMetallurgical and Materials Eng. Dept. Middle East Technical University Ankara Turkey

A phenomenological kinetic model has been developed for the prediction of non-isothermal reversible incomplete transformations in low-carbon hypoeutectoid steels. The theoretical basis of the proposed method has its origin in a possible extension of the traditional Austin-Rickett kinetic differential equation. To critically assess the applicability of the model, a number of experiments based on computer simulations have been performed to predict the austenite/ferrite proeutectoid transformation in the temperature range of Aei to Ae3 on plain carbon hypoeutectoid steels. A comparison with published experimental data has verified that the model developed is reasonable both quantitatively and with respect to well-established trends. Extension of the method of prediction appears promising when the non-isothermal reactions occurring during heat treatment (such as carbide precipitation and dissolution) can be assumed to proceed in a reversible manner.

关键词：奥氏体转变动力学低碳钢临界温度