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Spatial Pseudo Panel Data Models with an Application to Mincer Wage Equations

Selahattin Güris Gizem Kaya Aydin
Central European Journal of Economic Modelling and Econometrics | 2022 | No 1 | 37-56 | DOI: 10.24425/cejeme.2022.140511
Keywords spatial econometrics pseudo panel data Mincer wage equations
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Abstract

The studies using Mincer equations are generally applied to cross-sectional data at the micro-level. There are however limited studies conducted with macro or panel data for wage equations. Pseudo panel data methods can be applied to empirical studies by creating cohorts from repeated cross-sectional data in the absence of genuine panel data. Difference in both the human and labour resources according to the spatial positions may also affect the prediction of the wage equations. We aim to introduce the application of spatial pseudo panel models by creating cohorts according to the birth years of employees and regions in which they live from the Turkish household labour survey for the period 2010-2015. As a result, we find that the spatial autocorrelation model is appropriate for wage equations of Turkey. We also find that return of education on wages is 11% while return of experience on wages is 4%.
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Authors and Affiliations

Selahattin Güris
1
Gizem Kaya Aydin
2
  1. Marmara University, Department of Econometrics, Istanbul, Turkey
  2. Istanbul Technical University, Department of Management Engineering, Istanbul, Turkey

Pollen morphology in the tribe Nigelleae (Ranunculaceae): a worldwide palynological investigation into the species

Serap Işık Emel Oybak Dönmez Zübeyde Uğurlu Aydin Alİ A. Dönmez
Acta Biologica Cracoviensia s. Botanica | 2019 | vol. 61 | No 1 | 93-102 | DOI: 10.24425/abcsb.2019.127738
Keywords Garidella Komaroffia multivariate analysis Nigella Ranunculaceae pollen morphology
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Abstract

The pollen morphology of many collections of taxa of the tribe Nigelleae from the family Ranunculaceae which occur worldwide is presented in this study. A total of 88 specimens from 21 taxa, some of which were recently proposed, belonging to the genera Komaroffia, Garidella, and Nigella of Nigelleae were examined using light microscopy (LM) and scanning electron microscopy (SEM). In the tribe, the pollen type is mostly trizonocolpate, but in many taxa and specimens, both trizonocolpate and non-trizonocolpate types occur together. The pollen grains are small to medium (25–53.75 μm × 20–55 μm) in size and oblate to prolate in shape. The exine pattern at the mesocolpium in all the taxa investigated is similar: micro-echinate in LM and micro-echinate-punctate in SEM. The colpus membrane in Komaroffia and Nigella is micro-echinate in both LM and SEM. In Garidella, it is micro-echinate in LM but echinate (spinulose) in SEM. In this study, multivariate analyses, principal component analysis (PCA), and unweighted pair group method with arithmetic mean (UPGMA), were used to evaluate relationships between the genera and species within the tribe with respect to pollen morphology. PCA results show three main groups in the tribe: Garidella, Komaroffia, and Nigella. Moreover, the UPGMA tree also chiefly supports generic segregation into the smaller genera. An overall synthesis of the pollen characteristics of the three genera is provided and discussed.

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Authors and Affiliations

Serap Işık
Emel Oybak Dönmez
Zübeyde Uğurlu Aydin
Alİ A. Dönmez

Pollen Morphology of Polygala L. (Polygalaceae) from Turkey and its Taxonomic Implications

Emel Oybak Dönmez Zübeyde Uğurlu Aydın Ali A. Dönmez
Acta Biologica Cracoviensia s. Botanica | 2023 | Vol. 65 | No 2 | 6522 | DOI: 10.24425/abcsb.2023.145596
Keywords cluster analysis pollen Polygala principal component analysis taxonomy
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Abstract

Pollen morphology of Polygala taxa from the family Polygalaceae in Turkey is presented in this study. Pollen features of 18 species along with one undescribed species in the section Polygala were examined with light and scanning electron microscopy, 11 of which were studied and defined for the first time. Cluster analysis and principal components analysis were conducted to determine informative palynological characters and to discover similarities among the studied taxa. Based on qualitative and quantitative variables in the phenogram, the studied taxa were divided into three major clusters. Multivariate analyses revealed that apocolpium characters, including a psilate apocolpium, the presence of apocolpial lumens with granules and small depressions with psilate or rugulate walls are the most distinct features for discriminating Polygala taxa. Intraspecific variations in some pollen characters, such as the exine pattern and aperture membrane features, are reported for several taxa. Pollen morphological data obtained in the present study are compared with those from previous studies for a number of species, and the results are evaluated. In addition, the aperture number and its probable significance in the Turkish Polygala are considered for some taxa, with emphasis on their known pollination strategies.
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Authors and Affiliations

Emel Oybak Dönmez
1
Zübeyde Uğurlu Aydın
1
Ali A. Dönmez
1
  1. Hacettepe University, Faculty of Science, Department of Biology, Beytepe, Ankara, Turkey

Virulence properties of Listeria monocytogenes isolated from meat and meat contact surfaces in a slaughterhouse

F. Tasci M. Sudagidan O. Yavuz A. Soyucok A. Aydin
Polish Journal of Veterinary Sciences | 2024 | vol. 27 | No 1 | 13-23 | DOI: 10.24425/pjvs.2024.149329
Keywords beef meat biofilm Listeria monocytogenes PCR PFGE virulence genes
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Abstract

Listeria monocytogenes is a ubiquitous microorganism that is isolated from a variety of sources such as soil, water, decaying vegetation, sewage, animal feeds, silage, farm environments and food-processing environments. This study aimed to determine the prevalence, serogroups, biofilm formation, virulence factor genes, and genetic relationships of L. monocytogenes strains isolated from beef meat and meat contact surfaces obtained from a slaughterhouse in Burdur, Turkey. In this study, a total of 179 beef meat and meat contact surface samples were analyzed for the presence of L. monocytogenes by polymerase chain reaction (PCR). Out of a total of 179 beef meat and meat contact surface samples, 83 (46.37%) were found to be contaminated with L. monocytogenes, with the highest incidence (53.01%) occurring in beef meat. In the present study, most of the isolated strains belonged to serogroups IIB and IVB (lineage I). The L. monocytogenes strain also contained monoA-B, prfA, plcA, plcB, mpl, hlyA, actA, gtcA, dltA, Fri, flaA, InlA, InlC, InlJ, and iap genes. Biofilm formation was not determined in the tested samples at pH 5.5 and different temperatures (4°C, 10°C, 25°C, and 37°C). However, strong biofilm formation was observed in 6.45% (2/31) of the strains at pH 7.0 after 48 h incubation at 37°C, and in 3.22% (1/31) of the strains at pH 7.0 after 48 h incubation at 4°C and 10°C. Pulsed-field gel electrophoresis (PFGE) results showed that L. monocytogenes isolates were clonally related, and cross-contamination was present. In addition, PFGE results also revealed that AscI had more distinguishing power than the ApaI restriction enzyme. These results indicate that L. monocytogenes detected from meat and meat contact surfaces in the slaughterhouse pose a potential risk to public health.
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Authors and Affiliations

F. Tasci
1
M. Sudagidan
2
O. Yavuz
2
A. Soyucok
3
A. Aydin
4
  1. Department of Food Hygiene and Technology, Faculty of Veterinary Medicine, Burdur Mehmet Akif Ersoy University, 15030, Istiklal Campus, Burdur, Turkey
  2. Scientific and Technology Application and Research Center, Burdur Mehmet Akif Ersoy University, Burdur, 15030, Istiklal Campus, Burdur, Turkey
  3. Department of Food Processing, Food Agriculture and Livestock Vocational School, Burdur Mehmet Akif Ersoy University, 15030, Istiklal Campus, Burdur, Turkey
  4. Department of Food Hygiene and Technology, Faculty of Veterinary Medicine,Istanbul University-Cerrahpasa, 34320, Avcilar, Istanbul, Turkey

Applying autoregressive models in analysis of GRACE-Mascon time-series

Ozge Gunes Cuneyt Aydin
Advances in Geodesy and Geoinformation | 2022 | vol. 71 | No 2 | e25 | DOI: 10.24425/agg.2022.141299
Keywords GRACE Mascon equivalent water thickness temporal correlation colored noise autoregressive models
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Abstract

This study discusses how to model the noise in a Gravity Recovery and Climate Experiment (GRACE)-Mascon derived Equivalent Water Thicknesses (EWT) time-series. GRACE has provided unique information for monitoring variations in EWT of continents in regional or basin scale since 2002. To analyze a GRACE EWT time-series, a standard harmonic regression model is used, but usually assuming white noise-only stochastic model. However, like almost all kinds of geodetic time-series, it has been shown that the GRACE EWT time-series contains temporal correlations causing colored noise in the data. As well known in geodetic modelling studies, neglecting these correlations leads to underestimating the uncertainties, and so misinterpreting the significancy of the parameter estimates such as trend rate, amplitudes of signals etc. In this study, autoregressive noise modeling, which has some advantageous compared to the approaches and methods frequently applied in geodetic studies, is considered for GRACE EWT time series. For this aim, three important basins, namely theYangtze, Murray–Darling and Amazon basins have been examined. Among some applied autoregressive models, the ARMA(1,1) model is obtained as the best-fitting noise model for analyzing the EWT changes in each basin. The obtained results are discussed in terms of forecasting, significancy and consistency with GRACE-FO mission.
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Authors and Affiliations

Ozge Gunes
1
ORCID: ORCID
Cuneyt Aydin
1
ORCID: ORCID
  1. Yildiz Technical University, Istanbul, Turkey

Impact of climate change on vegetation period of basic species of vegetables in Slovakia

Ján Čimo Karol Šinka Andrej Tárník Elena Aydin Vladimír Kišš Lucia Toková
Journal of Water and Land Development | 2020 | No 47 | 38-46 | DOI: 10.24425/jwld.2020.135030
Keywords average temperature basic species of vegetables climate change temperature changes vegetation period
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Abstract

The aim of the paper is to provide climatic data from the basic elements and characteristics of the energy balance in terms of the current state and in terms of trends and assumptions of their future changes in Slovakia. Climate change affect agriculture and its procedures. Changes in vegetation period in Slovakia of selected vegetables are presented in this study. We used for agro-climatic analysis one hundred climatological stations, which were selected to cover all agricultural re-gions up to 800 m a.s.l. Actual data and predictions were compared with time period 1961–2010. Due to homogeneity in data measurements, was chosen this period. We obtained climate trends and assumed map outputs of future climate chang-es by mathematical-statistical methods for horizons of years 2011–2020, 2041–2050, 2071–2080 and 2091–2100. We ana-lysed vegetation period changes of selected fruit vegetables, Brassica vegetables and root vegetable in field conditions with prediction to year 2100. In our results is shown the earlier beginning of vegetation period in a spring and later end in an autumn in last 30 years. The vegetation period is getting longer about 15–20 days for Capsicum annuum; 15–20 days for Brassica oleracea var. capitate; 10–15 days for Beta vulgaris subsp. vulgaris with comparation of nowadays situation and period 2091–2100.

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Authors and Affiliations

Ján Čimo
Karol Šinka
Andrej Tárník
Elena Aydin
Vladimír Kišš
Lucia Toková

Comparative analysis of multi-criteria decision making methods for the assessment of optimal SVC location

Faruk Aydin Bilal Gümüş
Bulletin of the Polish Academy of Sciences Technical Sciences | 2022 | 70 | 2 | e140555 | DOI: 10.24425/bpasts.2022.140555
Keywords Borda count method FACTS MCDM optimal location PSAT voltage stability
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Abstract

The goal of multi-criteria decision making (MCDM) is to select the most appropriate of the alternatives by evaluating many conflicting criteria together. MCDM methods are widely available in the literature and have been used in various energy problems. The key problems studied in electrical power systems in recent years have included voltage instability and voltage collapse. Different flexible alternating current transmission systems (FACTS) equipment has been used for this purpose for decades, increasing voltage stability while enhancing system efficiency, reliability and quality of supply, and offering environmental benefits. Finding the best locations for these devices in terms of voltage stability in actual electrical networks poses a serious problem. Many criteria should be considered when determining the most suitable location for the controller. The aim of this paper is to provide a comparative analysis of MCDM techniques to be used for optimal location of a static VAR compensator (SVC) device in terms of voltage stability. The ideal location can be determined by means of sorting according to priority criteria. The proposed approach was carried out using the Power System Analysis Toolbox (PSAT) in MATLAB in the IEEE 14-bus test system. Using ten different MCDM methods, the most appropriate locations were compared among themselves and a single ranking list was obtained, integrated with the Borda count method, which is a data fusion technique. The application results showed that the methods used are consistent among themselves. It was revealed that the integrated model was an appropriate method that could be used for optimal location selection, providing reliable and satisfactory results to power system planners.
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Authors and Affiliations

Faruk Aydin
1
ORCID: ORCID
Bilal Gümüş
2
ORCID: ORCID
  1. Department of Electrical and Electronics Engineering, Faculty of Technology, Marmara University, İstanbul 34722, Turkey
  2. Department of Electrical and Electronics Engineering, Faculty of Engineering, Dicle University, Diyarbakır 21680, Turkey

Influence of Particle Size and Sintering Temperatures on Electrical Properties of 0.94Na0.5Bi0.5TiO3-0.06BaTiO3 Lead Free Ceramics

Mert Gul Mevlüt Gurbuz Abdi B. Gokceyrek Aysegül Toktaş Taner Kavas Aydin Dogan
Archives of Metallurgy and Materials | 2020 | vol. 65 | No 2 | 609-614 | DOI: 10.24425/amm.2020.132799
Keywords Lead-free NBT-BT particle size sintering Electrical properties
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Abstract

In this study, lead-free 0.94 Na0.5Bi0.5TiO3-0.06BaTiO3 (NBT-BT) compositions at morphotropic phase boundary were successfully synthesized by solid-state reaction method. The effects of the particle size for various milling time (12-24-48 hours) and sintering temperatures (1100-1125-1150-1175oC for 2h) on the electrical properties of the NBT-BT ceramics were evaluated. Experimental results showed that particle size and sintering temperatures significantly affect the electrical properties of NBT-BT ceramics. The particle size of the ceramic powders decreasing while milling time increases to 48 hours. Particle size values for 0, 12, 24 and 48 hours (h) milled powders were measured as nearly 1.5 µm, 1 µm, 700 nm, and 500 nm respectively. The bulk density enhanced with increasing sintering temperature and showed the highest value (5.73 g/cm3) at 1150oC for 48h milled powder. Similarly, the maximum piezoelectric constant (d33) = 105 pC/N, electromechanical coupling coefficient (kp) = 25.5% and dielectric constant (KT) = 575 were measured at 1150oC for 48 h milled powder. However, mechanical quality factor (Qm) was reduced from 350 to 175 with decreasing particle size. Similarly, remnant polarization was dropped by decreasing powder particle size from 56 μC/cm2 to 45 μC/cm2.

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Authors and Affiliations

Mert Gul
Mevlüt Gurbuz
Abdi B. Gokceyrek
Aysegül Toktaş
Taner Kavas
Aydin Dogan

Some applications of the generalized Laplace transform and the representation of a solution to Sobolev-type evolution equations with the generalized Caputo derivative

Mustafa Aydin Nazim Mahmudov
Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 2 | e149170 | DOI: 10.24425/bpasts.2024.149170
Keywords degenerate evolution equation Sobolev generalized Laplace transform fractional derivative with respect to another function Mittag-Leffler type function
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Abstract

We introduce the Sobolev-type multi-term μ-fractional evolution with generalized fractional orders with respect to another function. We make some applications of the generalized Laplace transform. In the sequel, we propose a novel type of Mittag-Leffler function generated by noncommutative linear bounded operators with respect to the given function and give a few of its properties. We look for the mild solution formula of the Sobolev-type evolution equation by building on the aforementioned Mittag-Leffler-type function with the aid of two different approaches. We share new special cases of the obtained findings.
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Authors and Affiliations

Mustafa Aydin
1
ORCID: ORCID
Nazim Mahmudov
2 3
ORCID: ORCID
  1. Department of Medical Services and Techniques, Muradiye Vocational School, Van Yuzuncu Yil University, Tu¸sba 65080 Van, Turkey
  2. Department of Mathematics, Eastern Mediterranean University, Famagusta 99628 T.R. North Cyprus, Turkey
  3. Research Center of Econophysics, Azerbaijan State University of Economics (UNEC), Istiqlaliyyat Str. 6, Baku 1001, Azerbaijan

Prediction of Fracture Stress with Regard to Porosity in Cast A356 Alloy

H. Sahin M. Atik F. Tezer S. Temel O. Aydin O. Kesen O. Gursoy D. Dispinar
Archives of Foundry Engineering | 2021 | vo. 21 | No 4 | 21-28 | DOI: 10.24425/afe.2021.138675
Keywords Casting defects Mechanical properties A356 Bifilm porosity Fracture stress
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Abstract

Production of the defect-free casting of aluminium alloys is the biggest challenge. Porosity is known to be the most important defect. Therefore, many cast parts are subjected to several non-destructive tests in order to check their acceptability. There are several standards, yet, the acceptance limit of porosity size and distribution may change according to the customer design and requirements. In this work, the aim was targeted to evaluate the effect of size, location, and distribution of pores on the tensile properties of cast A356 alloy. ANSYS software was used to perform stress analysis where the pore sizes were changed between 0.05 mm to 3 mm by 0.05 mm increments. Additionally, pore number was changed from 1 to 5 where they were placed at different locations in the test bar. Finally, bifilms were placed inside the pore at different sizes and orientations. The stress generated along the pores was recorded and compared with the fracture stress of the A356 alloy. It was found that as the bifilm size was getting smaller, their effect on tensile properties was lowered. On the other hand, as bifilms were larger, their orientation became the dominant factor in determining the fracture.
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Authors and Affiliations

H. Sahin
1
ORCID: ORCID
M. Atik
1
F. Tezer
1
S. Temel
1
O. Aydin
1
O. Kesen
1
O. Gursoy
2
D. Dispinar
3
ORCID: ORCID
  1. Istanbul Technical University, Turkey
  2. University of Padova, Italy
  3. Foseco, Netherlands

A novel artificial intelligence-based hybrid system to improve breast cancer detection using DCE-MRI

İsmail Akgül Volkan Kaya Erdal Karavaş Sonay Aydin Ahmet Baran
Bulletin of the Polish Academy of Sciences Technical Sciences | 2024 | 72 | 3 | e149172 | DOI: 10.24425/bpasts.2024.149172
Keywords artificial intelligence artificial neural network deep learning DCE-MRI breast cancer detection and classification
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Abstract

The interpretation of breast magnetic resonance imaging (MRI) in the healthcare field depends on the good knowledge and experience of radiologists. Recent developments in artificial intelligence (AI) have shown advances in the field of radiology. However, the desired levels have not been reached in the field of radiology yet. In this study, a novel model structure is proposed to characterize the diagnostic performance of AI technology for individual breast dynamic contrast material–enhanced (DCE) MRI sequences. In the proposed model structure, Inception-v3, EfficientNet-B3, and DenseNet-201 models were used as hybrids together with the Yolo-v3 algorithm to detect breast and cancer regions. In the proposed model, DCE-MRI sequences (T2, ADC, Diffusion, Non-Contrast Fat Non-Suppressed T1, Non-Contrast Fat Suppressed T1, Contrast Fat Suppressed T1, and Subtraction T1) were evaluated separately and validation was made, thus providing a unique perspective. According to the validation results, the model structure with the best performance was determined as Yolo-v3 + DenseNet-201. With this model structure, 92.41% accuracy, 0.5936 loss, 92.44% sensitivity, and 92.44% specificity rates were obtained. In addition, it was determined that the results obtained without using contrast material in the best model were 91.53% accuracy, 0.9646 loss, 92.19% sensitivity, and 92.19% specificity. Therefore, it is predicted that the need for contrast material use can be reduced with the help of this model structure.
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Authors and Affiliations

İsmail Akgül
1
ORCID: ORCID
Volkan Kaya
1
ORCID: ORCID
Erdal Karavaş
2
ORCID: ORCID
Sonay Aydin
3
ORCID: ORCID
Ahmet Baran
1
ORCID: ORCID
  1. Department of Computer Engineering, Faculty of Engineering and Architecture, Erzincan Binali Yıldırım University, Türkiye
  2. Department of Radiology, Faculty of Medicine, Bandırma Onyedi Eylül University, Balıkesir, Türkiye
  3. Department of Radiology, Faculty of Medicine, Erzincan Binali Yıldırım University, Erzincan, Türkiye

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