1,721,037 research outputs found
Prediction of compressive strength of heavyweight concrete by ANN and FL models
Full text linkAkkurt, Iskender/0000-0002-5247-7850; Kilincarslan, Semsettin/0000-0001-8253-9357WOS: 000277940600001The compressive strength of heavyweight concrete which is produced using baryte aggregates has been predicted by artificial neural network (ANN) and fuzzy logic (FL) models. For these models 45 experimental results were used and trained. Cement rate, water rate, periods (7-28-90 days) and baryte (BaSO(4)) rate (%) were used as inputs and compressive strength (MPa) was used as output while developing both ANN and FL models. In the models, training and testing results have shown that ANN and FL systems have strong potential for predicting compressive strength of concretes containing baryte (BaSO(4))
Activation cross section for the Te-125(p,xn) reactions in 5.5-100.5 MeV energy range
No full textWOS: 000322854700041Some isotopes such as Iodine, are vital especially in medical science and thus production of those isotopes becomes important. In this study the cross sections of the Te-125(p,xn) reaction where iodine can be produced, were calculated for the 5.5-100.5 MeV energy range using TALYS-1.2 computer program. The calculated Te-125(p,xn) cross sections have been compared with the experimental Nuclear Reaction Data (EXFOR-Experimental Nuclear Reaction Data) obtained from the library and also results obtained by the ALICE/ASH code. It was seen that the agreement between all results is good and this reaction is an important way to produce iodine isotopes. (C) 2013 Elsevier Ltd. All rights reserved
Prediction of photon attenuation coefficients of heavy concrete by fuzzy logic
Full text linkAkkurt, Iskender/0000-0002-5247-7850; Kilincarslan, Semsettin/0000-0001-8253-9357WOS: 000284501700001The fuzzy logic (FL) model to determine the radiation shielding properties of concretes containing barite in the ratio of 0%, 50%, 60%, 70%, 100%, and different water-to-cement ratio (w/c) have been developed. For training of the networks in the model, w/c and barite ratio were input, while the photon attenuation coefficient was output. The FL results were compared with experimental results and correlation between experiment and FL was compared with the correlation between experiment and calculation (XCOM). It was found that the correlation between FL and experiment was better than the correlation between XCOM and experiment. (C) 2010 The Franklin Institute. Published by Elsevier Ltd. All rights reserved
Excitation functions of proton induced reactions of some radioisotopes used in medicine
No full textThe main purpose of this study is the investigation of a cross section of proton induced nuclear reactions. The excitation functions of the reactions: 56Fe(p,2n)55Co 58Fe(p,2n)57Co, 111Cd(p,2n)110In, 112Cd(p,2n)111In, 125Te(p,2n)124I, 126Te(p,2n)125I, 68Zn(p,2n)67Gawere investigated. These reactions were studied as the resulting radioisotopes are used in medical applications. Theoretical excitation functions have been calculated with TALYS 1.6 nuclear reaction simulation code. The calculated excitation functions are compared with the experimental data
Shielding property of natural biomass against gamma rays
No full textWOS: 000324904100003PubMed: 24912221Algae and cyanobacteria are capable living under harsh conditions in the natural environments and can develop peculiar survival processes. In order to evaluate radiation shielding properties of green algae; Chlorella vulgaris, Scenedesmus obliquus, and cyanobacteria; Synechococcus sp., Planktothrix limnetica, Microcystis aeruginosa, Arthrospira maxima, Anabaena affinis, Phormidium articulatum, and Pseudoanabaena sp. were cultured in batch systems. Air dried biomass was tested for its high tolerance to gamma-radiations in terms of linear attenuation coefficients. In the present work, the linear and mass attenuation coefficients were measured at photon energies of 1173 and 1332keV. Protection capacity of some biomass was observed to be higher than a 1-cm thick lead standard for comparison. Gamma ray related protection depends not only to thickness but also to density (g/cm(3)). Hence the effect of biomass density also was tested and significantly found the tested biomass absorbed more of the incoming energy on a density basis than lead. This paper discusses the a new approach to environmental protection from gamma ray, The findings suggest that the test samples, especially cyanobacteria, have a potential for reducing gamma ray more significantly than lead and can be used as shielding materials
An extensive study on the neutron-gamma shielding and mass stopping power of (70-x) CRT-30K<sub>2</sub>O-xBaO glass system for <SUP>252</SUP>Cf neutron source
No full textakkurt, iskender/0000-0002-5247-7850;The present study focuses on the charged-uncharged particles shielding performance of the addition of a mixed type of cathode ray tube (CRT) in a glass system that is irradiated by the Cf-252 neutron source via the MCNPX simulation and analytical calculations, as well as Phy-X: PSD and SRIM software. The CRT waste glass is inserted into the glass system with (70-x) CRT-30K(2)O-xBaO general formula for x = 0, 10, 20 mol% that produces CG1, CG2, and CG3 glass shielding materials. Using Watt Fission Distribution (WFD) and Doppler Effect (DE) the neutron-gamma photon spectra were extracted for shielded (in the presence of the glass materials) and unshielded (in air) cases. Some calculated attenuation parameters related to the neutron deduced that CG1 is the best neutron attenuator among the selected glass samples. Moreover, by increasing the density of the glass from CG1 to CG3, the ascending trend is observed for the linear attenuation coefficient (LAC, cm(-1)) of the studied glass, and the best shielding competence is monitored for CG3. Furthermore, two sharp peaks are found in Z(eff) graphs which may be due to K-edge absorption of Ba and Pb elements and by decreasing the Pb element from CG1 to CG3 the second peak gradually becomes smooth. In addition, Mass Stopping Power/ Projected Ranges of the proton (H-1) and alpha particles (He+2) are also estimated by SRIM code and findings show that CG1 can better stop proton and alpha particles in comparison with the other chosen glass structures
Saliency detection with hybrid artificial bee colony-firefly optimization method
No full textImplementation of optimization algorithms in image processing is a quite common area of research. Detecting salient fields in images can be used for problems such as object recognition, image segmentation or video tracking problems. This case makes the determination of saliency an important factor in image processing. The algorithms developed for salient region detection are divided into two approaches as bottom-up and top-down. The bottom-up techniques determine salient regions according to the data, and the top-down techniques discover these regions by the learning of visual information of a certain object. This paper presents an optimization technique for bottom-up saliency detection algorithm based on Hybrid Artificial Bee Colony- Firefly algorithm.Publisher's Versio
Monte Carlo simulation studies of collimator parameters for TARLA bremsstrahlung facility
Full text linkBu çalışma, 19-24 Ekim 2016 tarihleri arasında Antalya[Türkiye]’da düzenlenen 3. International Conference on Computational and Experimental Science and Engineering (ICCESEN)’da bildiri olarak sunulmuştur.In this work, calculations of the design of bremsstrahlung photon collimator within the scope of the Turkish Accelerator Center Project are presented. At TARLA facility (Turkish Accelerator Radiation Laboratory at Ankara), bremsstrahlung photons created by the accelerated electron beams, are transferred to the experimental area through the collimator, which has a conical geometry with length of 320 cm. In this study, Al, Fe and Cu materials were selected as collimator materials. All interactions between the collimator materials and Gaussian photon beam in 8-32 MeV energy range (8 MeV, 16 MeV, 24 MeV and 32 MeV) were taken into account. The entry radius, geometry and chosen materials are important parameters for collimator design. The photon fluence from collimator, secondary particle distributions and the number of photons, scattered from the collimator, were calculated as functions of these parameters. All calculations were made with the Monte Carlo code FLUKA. According to the results of these simulations, collimator with conical geometry, made of aluminium, with 0.25 cm entry radius, was determined to be appropriate for TARLA bremsstarhlung photon facility of Turkish Accelerator Center.Türkiye Devlet Planlama Teşkilatı DPT2006K-120470Süleyman Demirel Üniversitesi 3407-D2-1
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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