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Öğe A novel approach for spam email detection based on shifted binary patterns(Wiley-Blackwell, 2016-01-11) Kaya, Yılmaz; Ertuğrul, Ömer FarukAdvances in communication allow people flexibility to communicate in various ways. Electronic mail (email) is one of the most used communication methods for personal or business purposes. However, it brings one of the most tackling issues, called spam email, which also raises concerns about data safety. Thus, the requirement of detecting spams is crucial for keeping the users safe and saving them from the waste of time while tackling those issues. In this study, an effective approach based on the probability of the usage of the characters that has similar orders with respect to their UTF-8 value by employing shifted one-dimensional local binary pattern (shifted-1D-LBP) was used to extract quantitative features from emails for spam email detection. Shifted-1D-LBP, which can be described as an ordered set of binary comparisons of the center value with its neighboring values, is a content-based approach to spam detection with low-level information. To validate the performance of the proposed approach, three benchmark corpora, Spamassasian, Ling-Spam, and TREC email corpuses, were used. The average classification accuracies of the proposed approach were 92.34%, 92.57%, and 95.15%, respectively. Analysis and promising experimental results indicated that the proposed approach was a very competitive feature extraction method in spam email filtering.Öğe The effect of intrapreneurship and organizational factors on the innovation performance in hospital(Expert Projects, 2018-09) Ekingen, Erhan; Ekemen, Mehmet Ali; Yıldız, Ahmet; Korkmazer, FuatIn the context of environmental uncertainty and competition, organizations are trying to find new ways to improve their performance. The development of novelties based on innovation, especially in the service sector, is the departure point for many organizations. Intrapreneurship and organizational structure are important factors for organizations to improve the innovation performance. In this study, it is aimed to investigate whether intrapreneurship and organizational factors influence the innovation performance. The data were collected from a hospital by means of intrapreneurship scale, organizational factors scale and innovation performance scale. According to the results of Structural Equation Model analysis, intrapreneurship has positive influences on innovation performance. Organizational factors directly and indirectly affect innovation performance. Moreover, intrapreneurship has mediation effect between organizational factors and innovation performance. Lastly, Intrapreneurship enhances the effect of organizational factors on innovation performance.Öğe Synthesis, characterization and antioxidant activity of heterocyclic Schiff bases(Journal of the Chinese Chemical Society, 2020-08-04) Aral, Tarık; Dağ, Beşir; Kızılkaya, Hakan; Genç, Nusret; Erenler, RamazanSchiff base derivatives have gained great importance due to revealing a great number of biological properties. Schiff bases were synthesized by treatment of 4-amino-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one (1) with various aldehydes in methanol at reflux. In addition, diamine was reacted with an aldehyde to yield the corresponding Schiff bases. The structures of synthesized Schiff bases were elucidated by spectroscopic methods such as microanalysis, 1 H-NMR, 13C-NMR, and FTIR. Antioxidant activities of synthesized Schiff bases were carried out using different antioxidant assays such as 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH• ) scavenging, 2,20 -azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, and reducing power activity. (E)-4-((1H-indol-3-yl)methyleneamino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one (3), (E)-1,5-dimethyl-4-((2-methyl-1H-indol-3-yl) methyleneamino)-2-phenyl-1H-pyrazol-3(2H)-one (5), (E)-1,5-dimethyl-2-phenyl-4-(thiophen-2-ylmethyleneamino)-1H-pyrazol-3(2H)-one (7), (E)-1,5-dimethyl2-phenyl-4-(quinolin-2-ylmethyleneamino)-1H-pyrazol-3(2H)-one (9), (1S,2S, N1,N2)-N1,N2-bis((1H-indol-3-yl)methylene)cyclohexane-1,2-diamine (11), and (1S,2S,N1,N2)-N1,N2-bis((2-methyl-1H-indol-3-yl)methylene)cyclohexane-1,2-diamine (12) were synthesized in high yields. Compound 5 displayed a good ABTS•+ activity. Compound 3 revealed the outstanding activity in all assays. Compound 7 has the best-reducing power ability in comparison to other synthesized compounds. Although compounds 5, 11, 12 are new, compounds 3, 7, 9 are known. Due to revealing a good antioxidant activity, the synthesized compounds (3, 5, 7) have the potential to be used as synthetic antioxidant agents.Öğe Improvement of diode parameters in Al/n-Si schottky diodes with coronene interlayer using variation of the illumination intensity(Elsevier, 2017-12-15) Pakma, Osman; Çavdar, Şükrü; Koralay, Haluk; Tuğluoğlu, Nihat; Yüksel, Ömer FarukIn present work, Coronene thin films on Si wafer have been deposited by the spin coating method. It has been ultimately produced Al/Coronene/n-Si/In Schottky diode. Current–voltage (I-V) measurements have been used to determine the effect of illumination intensity in the Schottky diodes. The barrier height (ΦB) values increased as ideality factor (n) values decreased with a increase in illumination intensity. The ΦB values have been found to be 0.697 and 0.755 eV at dark and 100 mW/cm2, respectively. The n values have been found to be 2.81 and 2.07 at dark and 100 mW/cm2, respectively. Additionally, the series resistance (Rs) values from modified Norde method and interface state density (Nss) values using current-voltage measurements have been determined. The values of Rs have been found to be 1924 and 5094 Ω at dark and 100 mW/cm2, respectively. The values of Nss have been found to be 4.76 × 1012 and 3.15 × 1012 eV−1 cm−2 at dark and 100 mW/cm2, respectively. The diode parameters are improved by applying the variation of illumination intensity to the formed Schottky diodes.Öğe Optimization and evaluation of dry and minimum quantity lubricating methods on machinability of AISI 4140 using Taguchi design and ANOVA(SAGE Journals, 2020-07-05) Gürbüz, Hüseyin; Gönülaçar, Yunus EmreIn this work, it is aimed to study the effects of dry machining and minimum quantity lubrication application on machinability in turning AISI 4140 steel by utilizing different cutting parameters. Also, this study contains effects and optimization of cutting conditions (dry and minimum quantity lubricating), feed rate, and cutting speed on surface roughness (Ra) and main cutting forces (Fc) determined by employing the Taguchi method. At the end of experiments, it was established that compared to dry machining operations, minimum quantity lubricating significantly reduced cutting tool wear, while Fc and Ra decreased in general. Analyses of variance, regression analysis, signal-to-noise ratio, and orthogonal array were employed to analyze the effects and contributions of independent variables on dependent variables. The optimum levels of the dependent variables for reducing Fc and Ra using signal-to-noise rates were established. According to signal-to-noise ratios, minimum quantity lubricating had a more important effect on Fc and Ra than dry machining. The optimal conditions for Fc and Ra were at 0.16 mm/rev feed rate, 125 m/min cutting speed at minimum quantity lubricating. Analysis of variance results demonstrated that the feed rate is the most influential independent variable on Fc (93.976 %) and Ra (89.352 %). Validation test results exhibited that the Taguchi method and regression analysis were highly achieved methods in the optimization of independent variables for dependent variables. Taguchi optimization technique and regression analysis obtained from Fc (R2Tag. = 0.972 and R2Rag. = 0.997) and Ra (R2Tag. = 0.985 and R2Rag. = 0.996) measurements match really well with the experimental dataÖğe Model and formulation in grinding mechanism having advanced secondary rotational axis(SAGE, 2019-04-15) Adıyaman, Oktay; Demir, Zülküf‘‘Grinding Mechanism having Advanced Secondary Rotational Axis’’ is one of the newer plane surface grinding methods that has an uncommon abrasion mechanism. Unlike conventional methods, in Grinding Mechanism having Advanced Secondary Rotational Axis, there are two rotations of a wheel. The first rotation is the same as the conventional grinding methods, which is the circumferential rotation. The other rotation is the newly developed axial rotation, where the wheel rotates around itself perpendicular to its radial axis. In the grinding process, the grinding force, energy, power, and temperature are directly related to the material removal rate. In this article, the chip model in Grinding Mechanism having Advanced Secondary Rotational Axis was addressed and material removal rate was reformulated. The new chip ratio formula was adapted to the grinding force, energy, power, and temperature in the conventional plane surface grinding method. The chip formed in the conventional plane surface grinding method consists of two-dimensional xy plane. In Grinding Mechanism having Advanced Secondary Rotational Axis, on the other hand, the chips consist of threedimensional xyz plane. The reason behind this is the second rotation obtained in Grinding Mechanism having Advanced Secondary Rotational Axis (axial rotational motion). The chip model was obtained from the combination of two rotations in Grinding Mechanism having Advanced Secondary Rotational Axis. As a result, the resulting chip model increased the material removal rate only slightly and this increase was negligible. Accordingly, an increase in grinding force, energy, power, and temperature was observed at negligible rates.Öğe Doküman dili tanıma için yeni bir öznitelik çıkarım yaklaşımı: İkili desenler(Gazi Üniversitesi, 2016-12-14) Kaya, Yılmaz; Ertuğrul, Ömer FarukDoğal dil işlemenin önemli alt konularından biri olan dil tanıma (DT), bir dokümanın içeriğine göre yazıldığı dili belirleme işlemidir. Bu çalışmada, karakterlerin UTF-8 değerlerini birbirleri ile karşılaştırmalar sonucu elde edilen ikili desenler kullanarak yeni bir dil tanıma yaklaşımı, bir boyutlu yerel ikili örüntüler (1B-YİÖ) önerilmiştir. Önerilen yöntem farklı sayıda dillerden oluşan metinler içeren dört veri kümesi ile test edilmiştir. 1B-YİÖ ile dokümanlardan elde edilen öznitelikler kullanılarak farklı makine öğrenmesi yöntemleri ile sınıflandırma işlemi gerçekleştirilmiştir. Dört veri kümesi için sınıflandırma başarıları sırası ile %86.20, %92.75, %100 ve %89.77 olarak gözlenmiştir. Elde edilen sonuçlara göre önerilen öznitelik çıkarım yönteminin dil tanıma için önemli örüntüler sağladığı görülmüştür.Öğe An explicit version of the correspondence between noetherian modules with cartier maps and artinian modules with frobenius maps(Hacettepe University, 2020-10-06) Yeşil, MehmetIn this paper, we introduce an explicit version of the correspondence between Noetherian modules with Cartier maps and Artinian modules with Frobenius maps which recovers the correspondence given by R. Y. Sharp and Y. Yoshino, and the correspondence given by M. Blickle and G. Böckle.Öğe Characterization of an Early Bronze Age pottery group from the upper Tigris valley (Turkey) by means of spectroscopic and microscopic techniques(X-RAY Spectrometry, 2019-04-17) Kozbe, Gülriz; Bayazıt, MuratIn this archaeometric research potsherds from Kavuşan Höyük (a mound located in the upper Tigris valley) representing the Metallic Ware, a diagnostic ceramic group mostly found in north Mesopotamia was characterized using spectroscopic and microscopic techniques in order to differ the imitated ones, if exist, to reveal the production technologies and compare the results with the previous archaeometric works concerning Metallic Ware. For this purpose, optical microscopy, scanning electron microscopy equipped with energy dispersive spectroscopy, polarized energy dispersive X-ray fluorescence, X-ray diffraction, and micro-Raman spectroscopy were used. Two groups were specified as the calcareous “imitations” and the dominant noncalcareous ware as the real ones. The results suggested that the noncalcareous ware of Kavuşan was presumably not produced with the possible clay deposits mentioned in previous studies, which focused on the provenance investigation of a wide range of Metallic Ware samples from the upper Tigris valley. It was also concluded from the results that the calcareous imitations would presumably belong to a local (in the name of Kavuşan) or regional (the upper Tigris) production due to the geological and chemical affinities.Öğe Estimation of surface roughness and cutting speed in CNC WEDM by artificial neural network that employed trainable activation function(SAGE Journals, 2021-02-01) Gürbüz, HüseyinActivation functions are the most significant properties of artificial neural networks (ANN) because these functions are directly related with the ability of ANN in learning or modelling a system or a function. Furthermore, another reason for the significance of the fact that determination of optimal activation function in ANN is its relationship with success level. In this experimental study, the effects of different types of wire electrodes, cooling techniques and workpiece materials on surface roughness (Ra) and cutting speed (Vc) in wire electrical discharge machining (WEDM) were investigated by using trainable activation functions (AFt) and modelling them in ANNs. So far, a number of methods have been performed according to the data set in order to optimally predict Ra and Vc results. Among these methods, randomized ANN with AFt was found to be the best one for robust prediction according to RMSE values. While the value was 0.280 for Vc, it was 0.2104 for Ra. Optimum activation functions in Ra and Vc were found at first and third degree trainable functions, respectively.
