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Computerized detection of spina bifida using SVM with Zernike moments of fetal skulls in ultrasound screening

Konur, Umut

Article | 2018 | Biomedical Signal Processing and Control43 , pp.18 - 30

A computer aided detection scheme for the neural tube defect of spina bifida is proposed. Features from Zernike moments of fetal skull regions viewed by ultrasound are utilized in SVM classification. Rotational invariance of magnitudes of Zernike moments and their easy normalization with respect to translation and scale make them attractive for image and shape description. In particular, they are perfect candidates for classifying shapes of fetal skulls that possess markers of spina bifida. The automated detection system may act in decision support to help specialists avoid false negatives. Problems of rarity are handled with combin . . .ations of oversampling and undersampling. A variant of the synthetic minority oversampling technique (SMOTE) and random undersampling (RU) have been applied on training data. Experiments show the trade-off in various performance indicators depending on different sampling choices. The average values of 0.6276 F-measure and 0.6306 GMRP are achieved on non-sampled (original) test sets when training is performed using sampled data after 400% borderline-SMOTE followed by 50% RU with respective accuracy and specificity realizations of 94% and 98%. © 2018 Elsevier Lt Daha fazlası Daha az

Conversion of an industrial waste to an oil sorbent by coupling with functional silanes

Demirel Bayık, Gülçin | Altın, Ahmet

Article | 2018 | Journal of Cleaner Production196 , pp.1052 - 1064

The aim of the present study is to produce an oil sorbent from paper industry waste by reducing the water sorption capacity with silane coating. Waste material was pretreated and then coupled with two different kinds of alkoxysilane, by solution immersion process. Coated material was characterized by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and contact angle measurements. Oil and water selectivity from water surface were evaluated for three different oil types. Production cost of the sorbent was determined and compared with other commercial products. Effect of silane coupling on water sorpti . . .on percentage was more apparent for thinner oil film thickness which was 0.127 cm. The water percentage for uncoated sorbent at this film thickness was 38.24% for diesel-oil mixture. For surface coated material, water sorption percentages were 9.27% for (3-Aminopropyl)triethoxysilane (APS) and 10% for 3-(Trimethoxysilyl) propyl methacrylate (MPS). The results show that industrial waste can be converted into an oil sorbing material by silane coupling. After coating, the material can be a good alternative for the removal of spilled oil. © 201 Daha fazlası Daha az

Fatigue in jointless bridge H-piles under axial load and thermal movements

Karalar M. | Dicleli M.

Article | 2018 | Journal of Constructional Steel Research147 , pp.504 - 522

The seasonal and short-term temperature variations produce cyclic horizontal displacements in the continuous superstructure of jointless bridges and hence in the abutment piles. Thorough study of the available field measurement data for jointless bridges showed that the thermal-induced cyclic flexural strains in steel H-piles (SHPs) at the abutments are composed of large, primary small and secondary small flexural strain cycles. While the SHPs at the abutments of jointless bridges laterally deform and experience these cyclic flexural strains due to thermal effects, they also carry axial loads transferred from the superstructure thro . . .ugh the abutments. Review of the literature revealed that there is no specific study on the combined effects of axial load and thermal-induced/flexural strain cycles with various amplitudes on the low cycle fatigue (LCF) performance of jointless bridge SHPs. For this purpose, parametric experimental studies on full scale SHP specimens are conducted to simulate the cyclic behavior of SHPs under thermal effects in jointless bridges by considering the effect of axial load combined with large and small flexural strain cycles with various amplitudes. It is observed that at large flexural strain amplitudes, local buckling of the pile due to the effect of axial load adversely affects the LCF life of SHPs at the abutments of jointless bridges. Furthermore, it is observed that the effect of small flexural strain cycles on the LCF life of uncompact SHPs depends on the amplitude of large flexural strains and the amplitude ratio of the small and large flexural strains. © 2017 Elsevier Lt Daha fazlası Daha az

Fungal inhibition and chemical characterization of wood treated with novel polystyrene-soybean oil copolymer containing silver nanoparticles

Can, Ahmet | Sivrikaya, Hüseyin | Hazer, Baki

Article | 2018 | International Biodeterioration and Biodegradation133 , pp.210 - 215

In this study, Scots pine (Pinus sylvestris L.) samples were impregnated with autoxidized soybean oil polymer containing Ag nanoparticles (Agsbox) and polystyrene-soybean oil copolymer (AgPSsb) in order to inhibit white-rot fungus (Trametes versicolor). Chemical changes of the impregnated specimens were characterized by FTIR techniques. The higher concentration of nano preservative resulted in higher weight percent gain (WPG) in the impregnated samples. The samples impregnated with 1.5% of Agsbox, had the highest WPG (2.98%). The silver nanocomposite-impregnated wood specimens improved the anti-fungal properties. In addition, treatm . . .ent with 0.4% AgPSsb resulted in the lowest moisture content (23.4%) after decay tests. In the samples, the lowest weight loss (0.87%) due to fungal decay was observed with the use of 0.4 wt% of AgPSsb. Mass losses of Agsbox impregnated specimens at 1.5% and 0.04% were 2.86% and 4.61% respectively. The FTIR spectra of the specimens impregnated with the nanocomposites showed the impregnated components at the peaks of 2910 cm-1 and 1714 cm-1 in particular. © 2018 Elsevier Lt Daha fazlası Daha az

Impact of hybrid neural network on the early diagnosis of diabetic retinopathy disease from video-oculography signals

Kaya, Ceren | Erkaymaz, Okan | Ayar, Orhan | Özer, Mahmut

Article | 2018 | Chaos, Solitons and Fractals114 , pp.164 - 174

In this study, we introduce two hybrid artificial neural network models with particle swarm optimization algorithm to diagnose diabetic retinopathy based on the Video-Oculography signals. The hybrid models use Discrete Wavelet Transform and Hilbert-Huang Transform separately to extract features from the signals. The classification performance of both models is analyzed comparatively. We show that the model based on Hilbert–Huang Transform exhibits better classification performance than the model based on the Discrete Wavelet Transform. © 2018 Elsevier Ltd

Holistic sustainability assessment of green building industry in Turkey

Ulubeyli S. | Kazanci O.

Article | 2018 | Journal of Cleaner Production202 , pp.197 - 212

In the Turkish green building industry, firms need to do an industrial analysis as this market has an emerging nature and potentially unstable business environment. By performing such a strategic analysis, they may determine their own holistic sustainability approaches and thereby become long-lasting enterprises. Therefore, this paper presents a fuzzy model of the macro-environmental assessment (FMMA) in the green building industry in Turkey through PESTLE (political, economic, social, technical, legal, and environmental) framework. To achieve this objective, fuzzy synthetic evaluation was used in quantifying macro-environmental con . . .ditions (MECs). The required data for this analysis were obtained from professionals working in the national industry. To illustrate how FMMA works, the current case of the industry was presented. As a result, FMMA offers a comprehensive and practical tool. Given empirical findings, the effect of MECs on the industry was found to be medium-to-high. Also, technological factors were identified as the most effective group, followed by environmental, economic, legal, political, and social factors, respectively. Subsequent researches may examine other regions and industries by modifying the existing criteria and weights. Similarly, the green building industry may be investigated from the viewpoint of other parties in the market. Consequently, this study is first to offer a structured PESTLE quantification model and to evaluate MECs in this emerging industry. © 2018 Elsevier Lt Daha fazlası Daha az

New cockles (Bivalvia: Cardiidae: Lymnocardiinae) from Late Pleistocene Lake Karapınar (Turkey): Discovery of a Pontocaspian refuge?

Büyükmeriç Y. | Wesselingh F.P.

Article | 2018 | Quaternary International465 , pp.37 - 45

Three species of lymnocardiine cockles (Bivalvia: Cardiidae) from Late Pleistocene deposits near Karapınar (Konya Basin, Anatolia, South Turkey) are reported. Two of the three species are described as new (Monodacna pseudocolorata and Adacna yaninae). A third species (Hypanis ?plicatum) is represented by two incomplete valves. Radiocarbon ages of circa 35–43 kA were obtained for the fauna. The lack of lymnocardiine cockles in Pleistocene Anatolian inland lake deposits raises the possibility that the new record represents a short lived occurrence. We raise the possibility that the Karapınar Basin cockles may have been introduced from . . . the Black Sea region through avian dispersal, although we cannot rule out their cryptic existence in the region during the Pleistocene. The apparent absence of Monodacna colorata group of cockles in the Black Sea Basin during the last glacial raises the possibility that the Karapınar region may have served as a true refugium rather than just a sink for Pontocaspian biota. © 2016 Elsevier Ltd and INQU Daha fazlası Daha az

Inertial particle separation in curved networks: A numerical study

Dinler A. | Okumus I.

Article | 2018 | Chemical Engineering Science182 , pp.119 - 131

To rapidly separate and isolate specific-sized particles by inertial focusing from biological samples, microfluidic networks with curved branches have become subject of prototyping. However, determining the optimal channel dimensions for size-based separation is challenging due to the sophisticated fluid-particle interactions and high sensitivity of the inertial forces to the channel geometry. In the first part of the study, hydrodynamic forces acting upon the particle in the existence of the Dean vortices are modeled and simulated. Simulations are validated with available experimental data. Then, a series of computational experimen . . .ts is run for various curvatures and cross-section sizes, and translocation of particles through curved branches is projected. Width of the focusing band is predicted for different-sized particles. Occurrences of a narrow (high-quality) focusing, dispersion of the particles (no focusing) and split of the focusing band are also determined. Nevertheless, a considerable pressure drop is expected due to the narrow and high curvature daughters of the considered network. A design rule is not available to resolve this problem and the Murray's law is not valid for curved daughters. Therefore, in the second part of the study, an optimum design formulation for restraining the hydraulic resistance inside such networks is developed and tested. The proposed formulation can be practiced to predict the optimum length, curvature and aspect ratio of the daughter branches for such inertial separation networks. © 2018 Elsevier Lt Daha fazlası Daha az

Fauna and flora of drilling and core data from the İznik Lake: The Marmara and the Black Sea connection

Meriç E. | Nazik A. | Yümün Z. | Büyükmeriç Y. | Avşar N. | Yildiz A. | Sagular E.K.

Article | 2018 | Quaternary International486 , pp.156 - 184

The study deals with on the Quaternary connection of the Iznik Lake between the Gemlik Gulf and the Black Sea located in the Marmara Region. The core and drilling data were evaluated. They were collected at two locations and depths from drilling cores and at the three deepest locations of the lake. A total of 510 samples were examined from the lake-bottom cores. Ostracod, mollusc, nannoplankton, ascidian spicule, and diatom assemblages observed at different levels of the drillings were studied. No foraminiferal data were recorded. Molluscan association such as Dreissena bugensis, D. caspia, Monodacna pontica, Clathrocaspia makarovi, . . . Euxinipyrgula milachevitchi, Euxinipyrgula lincta indicate Neoeuxinian age. Amnicythere olivia, A. stepanaitysae, A. striatocostata, Tyrrhenocythere amnicola and Loxoconcha immodulata of the ostracod assemblage, exhibiting Ponto-Caspian origin, were found. In addition, fossil ascidian spicules comprising various species of Bonetia, Micrascidites, Monniotia, and Rigaudia genera were encountered, probably representing Late Pleistocene to Holocene ages. Campylodiscus echeneis, Cocconeis placentula var. lineata Epithemia turgida var. granulata, Epithemia adnata, Nitzschia commutate and N. vermicularis, from the diatom assemblage are genera and species also found in the İznik Lake and in the Black Sea. Mollusc and ostracod fauna, the Ponto-Caspian origin indicates that the İznik Lake was connected with the Black Sea and the Marmara Sea in the recent period. Thus, the Ponto-Caspian assemblages indicate the early Neoeuxinian (Surozhian) brackish water inundated the study area. Geochronological ages determined by the 14C method from the deposits occurring at 53–54 m above present sea level in the İznik Lake indicate the periods of connection via Iznik Lake during 33,630 to 32,920 cal BP (SK-1) and BP 27,335 to 27,070 cal BP (SK-2). When the position of the deposits is compared with the previously available Late Pleistocene 14C data obtained from the molluscs identified in the nearby Gemlik Gulf at -76 m present water depth and also with the early Khazarian (Middle Pleistocene) age data on the molusc fauna at 130–150 m heights of uppermost terraces above present sea level to NW of the lake, we suggest the influence of a neo-tectonic regime for the occurrence of comparable age deposits at different levels in the region. It may be proposed that a vertical displacement in the order of a 100 m occurred since the late Pleistocene in the İznik Lake area and the lake acquired its present features as a result of the tectonic movements. © 2017 Elsevier Ltd and INQU Daha fazlası Daha az

Electrochemical and photovoltaic properties of highly efficient solar cells with cobalt/zinc phthalocyanine sensitizers

Sevim A.M. | Çakar S. | Özacar M. | Gül A.

Article | 2018 | Solar Energy160 , pp.18 - 24

The cyclic voltammetry studies indicated that the HOMO and LUMO energy levels of three sensitized metallophthalocyanines could ensure efficient electron injection and thermodynamically favorable dye regeneration. The S-bridged 4-mercaptobenzoic acid substituted cobalt(II) phthalocyanine (4-MKBa-CoPc) sensitized solar cell devices possessed a short-circuit photocurrent density of 9.70 mA/cm2, an open-circuit voltage of 0.88 V, and a fill factor of 0.49, corresponding to an overall conversion efficiency of 4.18% under standard AM 1.5 sun light. The present results demonstrated that the cobalt(II) phthalocyanine derivative had dramatic . . .ally higher solar cell efficiency value as compared to zinc(II) phthalocyanine and as a linker atom, instead of oxygen linker, sulfur atoms slightly improved solar cell efficiency. The above results indicated that a low cost sensitizer made up of symmetrically substituted phthalocyanine with an earth abundant metal at the inner core can reach sufficiently high solar cell efficiency when compared with the alternative sensitizers for DSSCs applications. © 2017 Elsevier Lt Daha fazlası Daha az

Particle migration and surface modification on Ti6Al4V in SiC powder mixed electrical discharge machining

Öpöz T.T. | Yaşar H. | Ekmekci N. | Ekmekci B.

Article | 2018 | Journal of Manufacturing Processes31 , pp.744 - 758

The study examines the impact of SiC powder concentration on surface topography, particles deposition and subsurface structures in powder mixed electrical discharge machining (PMEDM) of Ti-6Al-4V-ELI work material. It was observed that low pulse currents and high suspended particle concentration in dielectric liquid enhance the material transfer mechanism in particulate form. The subsurface properties of such surfaces exhibited a distinctive and harder re-solidified layer structure that indicates a unique material transfer mechanism takes place during machining. The particles placed close to a discharge column directed towards the m . . .elted metal pool due to the sudden closure of the plasma channel. When the main discharge channel subdivided into several secondary discharges, the suspended particles in dielectric liquid stuck among the scattered sub discharges and increased the probability of penetrating into the melted metal pool at the end of a discharge. Therefore, the formation of secondary discharges favoured the improved SiC transfer in particulate form. However, increasing the pulse current deplete the material transfer mechanism in particulate form due to the inadequacy of secondary discharges. © 201 Daha fazlası Daha az

Calculation of productions of PET radioisotopes via phenomenological level density models

Artun O.

Article | 2018 | Radiation Physics and Chemistry149 , pp.73 - 83

In the present paper, we have explained the phenomenological level density models to utilize it in the production of positron emission tomography (PET) radioisotopes. To achieve this aim, the cross-sections of reaction processes were calculated by TALYS code for the level density models. Additionally, to estimate the production of PET radioisotopes, the integral yield curves of reactions for three different level density models were calculated using the mass stopping power obtained from X-PMSP program in the particle beam current of 1 µA and irradiation time 1 h. Based on these results, we discussed the suitable level density model . . .for the production of PET radioisotopes. © 2018 Elsevier Lt Daha fazlası Daha az

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