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Koleksiyondaki öğeler
- MakaleYayıncıda açık erişim2025Scopus SJRQ4ANALYSIS OF PESTICIDES, ANTIBIOTICS, AND HEAVY METAL LEVELS IN HONEY PRODUCED IN THE BAYBURT AND UPPER ÇORUH VALLEY REGIONS OF TÜRKİYE; [Türkiye'nin Bayburt ve Yukarı Çoruh Vadisi Bölgelerinde Üretilen Ballarda Pestisit, Antibiyotik ve Ağır Metal Düzeylerinin Analizi]
Özdemir, Mustafa; Yildizlar, Osman
This study investigates pesticide, antibiotic, and heavy metal levels in Bayburt and the Upper Çoruh Valley honey. Thirteen honey samples were collected from different apiaries managed by stationary and migratory beekeepers. These samples were analysed for heavy metals (Fe, Cu, Zn, Cd, Pb), antibiotics, pesticides, and chemical residues such as naphthalene. The results revealed that lead (Pb) levels exceeded international food safety standards in 2 honey samples, while pesticide residues were detected in 5 samples. Additionally, antibiotic residues were found in 6 samples, including sulfamethazine, tetracycline, and streptomycin. However, no naphthalene was detected in any of the samples. These findings highlight the importance of stricter regulations and monitoring systems to control chemical use in beekeeping practices. Enhancing awareness among beekeepers regarding the risks associated with pesticide and antibiotic use is crucial for improving honey quality and ensuring the health of beekeepers and consumers. The adoption of safer practices and adherence to guidelines are necessary to mitigate these health hazards.
AtıfOpenAlex1TR Dizin2
İncele - MakaleAçık Erişim2020Scopus SJRQ1Propagation constant measurements of reflection-asymmetric and nonreciprocal microwave networks from S-parameters without using a reflective standard
Hasar, Ugur Cem; Kaya, Yunus; Ozturk, Gokhan; Ertugrul, Mehmet
We propose a simple method for determination of forward and backward propagation constants of nonreciprocal uniform networks or lines with asymmetric reflections. The wave cascading matrix presentation is used to diagonalize and decompose the line in terms of impedance and amplitude/phase transitions. The proposed method uses scattering parameters of the line/network connection and the thru connection, thus eliminating errors arising from fabrication tolerance and thickness of the second line. Besides, compared with conventional methods which necessitate calibration techniques such as the thru-reflect-line, our method has the advantage that it determines propagation constants without resorting the measurement of any reciprocal reflective standard. Propagation constant measurements of a reciprocal network (different-length X-band waveguide straights) and a nonreciprocal network (microwave phase shifter) were first carried out and then compared with those measured by different methods to validate and monitor the accuracy of our method.
AtıfScopus13WoS12OpenAlex11
İncele - MakaleYayıncıda açık erişim2024Scopus SJRQ2Nonlinear optical properties of KnCl (n = 2-7) superalkali clusters
Şentürk, Şükrü; Fardad, Fraidoon; Ekincioğlu, Yavuz
The lowest energy structures along with the low lying isomer, stabilities, electronic properties, optical properties and nonlinear optical responses of KnCl (n = 2-7) clusters were studied within the density functional theory. The second order energy difference, dissociation energy and GH-L (HOMO-LUMO gap) point out that KnCl (n = 3, 5, 7) clusters are more stable. The calculated adiabatic ionization energies (AIE) for the KnCl (n = 2-6) clusters are in agreement with the measured ionization energies. The optical properties, namely optical electronegativity and refractive index, depends on the GH-L energy values. The K atom capped planar rhombus geometry of the K4Cl causes the noticeable vibrational frequency shift compared to the rest of IR spectra of the clusters. The first static hyperpolarizability (β o) values are in the range of 2.33 × 103-2.87 × 104 au and the second static hyperpolarizability varies between 5.74 × 106 au and 38.9 × 106 au for the cluster. The nonlinear optical response is due to the superalkali nature of KnCl (n = 2-7) clusters. From computed β vec values, the hyperpolarizability has projection on the dipole moment vector for the superalkalis except the K2Cl and K5Cl. The absorption spectra point out that KnCl (n = 6-7) clusters can be suitable as a NLO material since they have transparency in the deep UV region (λ< 300 nm).
AtıfScopus2WoS2OpenAlex3İncele - MakaleAçık Erişim2024Scopus SJRQ3Investigation of Microbiological, Physiological and Histopathological Changes in Polymicrobial Infection in Old Rats
Ülker, U.; Kızıl, S.; Bayraktar, B.; Alçığır, M.E.; Kul, O.; Kaya, H.; Ürüşan, H.; Aydemir, Ş.; Kotan, G.C.; Önel, A.U.
Background: The aim of this study is to examine the microbiological, clinical, physiological and pathological findings of natural polymicrobial infection developing in a wistar rat colony under long-term observation. Methods: In this study, 70 male Wistar albino rats, 3 years old, raised by conventional methods and housed in a cage environment were used. Thirteen rats with clinical symptoms such as torticollis and rotation were sacrificed for microbiological and histopathological examination after 14 days. For microbiological examination, the rapid diagnostic kit BBL Crystal system was used to identify bacterial agents in tissue and stool samples and the traditional culture method was used for isolation. Result: As a result of microbiological analysis, the rarely isolated Staphylococcus capitis (S. capitis) was isolated. Different Staphylococcus spp. It has been determined that the species can cause suppurative meningoencephalitis as well as septicemia in the brains of experimental animals., it is thought that polymicrobial infection will be useful for the identification of bacterial agents and infection prevention and treatment strategies.
- Kitap BölümüYalnız künye2022Diplomatic transformation of series narrative: Velvet evolution of representation from valley of the wolves to valley of the wolves-ambush
Keskin, Savaş
In addition to what the studies on the discourse and character modeling of the Valley of the Wolves series say, this chapter argues that there has been a Neo-Ottomanization and religiosity evolution in terms of the discourse and the hero's semiosis. The thesis of this section is that Valley of the Wolves series has evolved in terms of narrative and character since it began to appeal to international target audiences. It is the main assumption of the section that there is a parallel transformation with the public diplomacy practices of the Republic of Turkiye in the process following the fact that the audience groups, especially in Arab geography, Afghanistan and Pakistan, where Islamic influence is dominant, become fans of the Valley of the Wolves. In this section, it is aimed to explain the velvet evolution, which exemplifies the transition from the Republican ideology to the Neo-Ottoman ideology in diplomatic media narratives, through the historical rupture of the Valley of the Wolves.
AtıfScopus1İncele - MakaleYalnız künye2023Scopus SJRQ3Methoxy-activated indole-7-carbohydrazides; synthesis, antioxidant, and anticancer properties
Kandemir, Hakan; İzgi, Samet; Cınar, Irfan; Cebeci, Fatma; Dirican, Ebubekir; Saglam, Mehmet F.; Sengul, Ibrahim F.
Indole has been known as a key heterocyclic motif in the development of new structures for both chemical and biological properties. In this current study, a new range of indole-7-carbohydrazides has been successfully synthesized starting from the readily available 3-phenyl and 2,3-diphenyl 4,6-dimethoxyindoles. The structures of the novel compounds were confirmed by utilizing 1H NMR, 13C NMR, FT-IR, high-resolution mass spectrometry, and single crystal X- ray diffraction techniques. In addition, the indole-7-carbohydrazides showed promising antioxidant results in preliminary screens. Some of the new compounds generated from dimethoxy indoles were also screened for their anticancer activity against SH-SHY5Y (human neuroblastoma), AGS (human gastric adenocarcinoma), and MDA-MB-231 (human breast adenocarcinoma) cell lines. The results revealed that the compound 12 was the promising candidate, showing cytotoxic effects on both neuroblastoma, stomach, and breast cancer cells.
AtıfScopus4WoS4OpenAlex6İncele - MakaleAçık Erişim2023Scopus SJRQ1Evaluation of Optimal Energy Productıon Usıng Deterministic, Probabilistic and Risky Cases In a Multi-Reservoir System
Bacaksız, Efsun; Opan, Mücahit; Kara Dilek, Zuhal Elif; Karadeniz, Murat
In a multi-reservoir system, the stochastic nature of basin data resulting from rainfall introduces risk into water management operations. Effective management that accounts for these risks can obtain maximum benefits from the system. This study presents a description of a multi-reservoir water resources system with hydroelectric power plants, utilizing the energy optimization model developed by OPAN in 2007. The model was applied to reservoirs located successively on the Lower Kızılırmak River in the Kızılırmak Basin, with the objective function being the maximization of firm power by using drought period inflows and total energy by using monthly average inflows. The study considered three scenarios: deterministic, probabilistic, and risky (critical cases), with probabilities of inflows from the basin being determined for the latter. Monthly inflows with determined probabilities were used to obtain data for the risky case. Optimum operating levels were determined based on this data to maximize firm power and total energy. According to the operating levels, the reservoir with the largest useful volume manages the operation. The values obtained from the optimization were then used in multivariate regression analysis using the Statistical Package for Social Scientists (SPSS), a statistical analysis program. The analysis explored the effects of monthly operating levels in the reservoirs, the amount of inflow released from the spillway, the amount of inflow released for energy production, the monthly average inflow to the reservoirs, and firm power values on energy production.
AtıfScopus7WoS6OpenAlex7İncele - MakaleAçık Erişim2023Scopus SJRQ3Bounds for the blow-up time a class of integro-differential problem of parabolic type with variable reaction term; [Bornes sur le temps d’explosion pour une équation intégro-différentielle de type parabolique avec un terme réactif variable]
Ayazoglu, Rabil; Akkoyunlu, Ebubekir
This paper is concerned with the blow-up time of the solutions to an integro-differential problem of parabolic type with variable growth if blow-up occurs. By using the differential inequality technique, we obtain lower bounds for the blow-up time and some global existence results under some conditions to variable exponent of reaction, memory kernel, and initial value.
AtıfScopus1WoS1İncele - MakaleAçık Erişim2023Scopus SJRQ3An Investigation of Digital Transformation Activities of Higher Education in Türkiye
Yavuz, Mehmet; Kayalı, Bünyami; Karaman, Selçuk
This study aimed to examine the digital transformation activities of universities. The document analysis method was used in the study, one of the qualitative research methods. In this context, the websites of 207 universities were examined using the "Digital transformation activities form of universities" developed by the researchers. The data were analyzed by content analysis method. As a result of the analysis, six broad themes, also called dimensions in the current study, emerged, such as research, education, culture, process, technology, and community service regarding digital transformation activities of higher education institutions. Infrastructure studies, educational activities for research and supply and the use of smart systems to provide various cooperation opportunities are discussed within the scope of the research dimension. There are online scientific studies, online education programs, digital resources, and open access opportunities in the education dimension. As for the culture dimension, online manager activities for corporate culture, training of trainers, culture-arts and scientific activities took place. With the transfer of business processes to the digital environment, corporate promotion and communication activities were included in the process dimension. In the technology dimension, smart systems, smart campus applications and innovative technologies took place. Finally, the scope of community service compromised related units, university-industry cooperation activities and social activities. As a result, universities carry out activities to support processes such as education, research, management, and cooperation and to realize them in digital environments. For this purpose, it can be said that they perform effective and efficient processes by using various intelligent systems.
AtıfScopus7OpenAlex10İncele - MakaleAçık Erişim2025Scopus SJRQ3Effect of Moringa oleifera Oil Extract on Adipokine (Apelin, Visfatin and Nesfatin-1) and Cardiac (cTnI) Response in Streptozotocin-induced Rats
Orkun Erkiliç, Tuğçe; Bayraktar, Bülent
Background: The aim of this study was to investigate the effects of Moringa oleifera extract (MOE) added to the diets at different amounts on Adipokine (apelin, visfatin and nesfatin-1) and Cardiac (cardiac troponin I (cTnI)) Response in Streptozotocin (STZ)-induced Type 1 diabetic rats. Methods: In this study, 64 adult male Wistar albino rats, aged between 8-10 weeks, were used. Eight (8) groups were created, with 8 rats in each group: Control (C), M100 (MOE 100 mg/kg group given with oral gavage route of administration (OGRA), M200 (MOE 200 mg/kg group given with OGRA), M300 (MOE 300 mg/kg group given with OGRA); STZ 55 mg/kg i.p administered group, Diabetic control group (DC), DM100 (D+100 mg/kg MOE), DM200 (D+200 mg/kg MOE), DM300 (D)+300 mg/kg MOE). The study lasted a total of 31 days, including adaptation (7 days), induction of diabetes (3 days) and trial period (21 days). Blood samples were taken from the tail vein (Vena caudalis) of all subMects on days 0 and 21 of the study. Apelin, visfatin, nesfatin-1 and cTnI levels in the serum samples were measured by ELISA method. Result: In the present study, the most significant increase in mean serum apelin, visfatin, nesfatin-1 and cTnI levels in diabetes groups was observed in DC groups, while the most significant decrease due to MOE addition was observed in DM200 groups (p<0.01). As a result, it was concluded that MOE may be safe and beneficial when administered at a dose of 200 mg/kg in rats with STZ-induced diabetes.
AtıfScopus3WoS4İncele - MakaleYalnız künye2023Scopus SJRQ1Honey-Water Content Analysis by Mixing Models Using a Self-Calibrating Microwave Method
Hasar, Hafize; Hasar, Ugur C.; Kaya, Yunus; Ozturk, Hamdullah; Izginli, Mucahit; Oztas, Taskin; Aslan, Nevzat; Ertugrul, Mehmet; Barroso, Joaquim J.; Ramahi, Omar M.
Microwave techniques, as an indirect approach, can be applied for analyzing water content in honey by way of permittivity measurements. However, these techniques require proper calibration to accurately perform such indirect evaluation. Improper calibration standards used in this calibration process could naturally result in a reduction in the accuracy and thus the performance of dielectric characterization using microwaves. Self-calibrating microwave techniques can reduce the effects of imprecise standards and thus improve the performance of microwave measurements by bypassing the requirement of calibration standards. In this study, we develop a self-calibrating microwave measurement technique to determine the relative permittivity of honey samples and implement binary mixing models to predict adulteration levels of water-adulterated honey. From this implementation, it is observed that the parallel-capacitance mixing model could efficiently be applied to determine the concentration of water adulteration by examining the differences between absolute values of the real parts of the measured and predicted complex permittivities of adulterated honey.
AtıfScopus18WoS16OpenAlex18İncele - MakaleAçık Erişim2024Scopus SJRQ2Optimization of a Novel–Enriched Pasta Production and Its Physical, Chemical, and Characteristic Properties
Yilmaz, Merve Silanur; Kutlu, Naciye; Sakiyan, Ozge; Isci, Asli
The aim of the study is to enrich pasta with cornelian cherry powder, a product with high bioactive contents. In this way, it was aimed to obtain a new product that is more nutritionally advanced and can contribute to the country’s economy. In this study, cornelian cherry with high bioactive content and an attractive color advantage was used for the enrichment of the pasta formulation. In addition, the pasta production procedure was revised by applying microwave technology for drying. Cornelian cherry powder:dough ratio, dough thickness, and microwave power were optimized with response surface methodology. Total phenolic content, antioxidant activity, color, and water-holding capacity were determined as responses. Optimum conditions were found as 4.53% for powder:dough ratio, 0.1 cm for dough thickness, and 270 W for microwave power. According to optimization results, it was detected that the cornelian cherry powder:dough ratio affected the total phenolic content and antioxidant activity, and microwave power was found to be effective only on antioxidant activity. For optimum conditions, the total phenolic content and antioxidant activity were found as 1.29 GAE/g and 0.5 mg TE/g, respectively. The characterization analysis showed that the microwave–dried sample shrank less than those dried with the conventional method. In Fourier transform infrared spectroscopy (FTIR) results, it was determined that the amount of carbohydrates in the samples obtained under optimum conditions was lower than that of control. It has been observed that the application of microwave technology for drying pasta enriched with cornelian cherry powder had positive effects on the quality of the final product.
AtıfScopus2WoS2OpenAlex2İncele - MakaleYayıncıda açık erişim2022Scopus SJRQ1Time-dependent fresh properties characterization of 3D printing engineered cementitious composites (3DP-ECC): On the evaluation of buildability
Zhou, Wen; McGee, Wes; Zhu, He; Gökçe, H. Süleyman; Li, Victor C.
Failure of the structure due to poor buildability is a major concern in 3D printing of cementitious materials. Evaluation of buildability based on fresh material properties and print parameters is of significance. In this paper, the buildability of printable engineered cementitious composites was investigated and quantified at the material and the structural scale. Fresh ECC material showed excellent load capacity and deformation resistance at the material scale, therefore preventing material failure of the bottom layers, as confirmed by constant shear rate tests and incremental loading tests. To predict vertical deformation of a 3DP structure, a time-dependent strain-stress model of printable ECC was proposed and validated based on the green strength evolution of the material and the buildup rate of the designed structure. At the structural scale, the approach of predicting critical height at self-buckling failure based on stiffness evolution was validated by printing a straight wall and a cylinder structure.
AtıfScopus56WoS46OpenAlex52İncele - MakaleAçık Erişim2023Scopus SJRQ3EVALUATION OF YIELD AND QUALITY CHARACTERISTICS OF OIL SUNFLOWER (Helianthus annuus L.) VARIETIES CULTIVATED IN SEMI-ARID IRRIGATED CONDITIONS IN THE NORTHEAST OF TURKEY
Gul, Volkan; Gidik, Betul; Sefaoglu, Firat
Sunflower, an oil plant grown in many parts of the world, is capable of growing in many different climatic conditions. It is of great importance to carry out studies on the adaptation of new varieties and to determine the varieties suitable to the ecology of the region in areas where sunflower cultivation is intense. This study was carried out to determine yield and quality characteristics of some sunflower cultivars (SANBROMR, BOSFORA, SYBARBATI, ROSETTA, LG5485, P64LL62, SYGIBRALTAR, P64LC108 P64LE119, P64LP130, P63LE113, 11TR077, ESNIEGARA, ADELYA, and DERAY) under Bayburt providence conditions of Turkey in 2020-2021. It has been determined that there are significant differences between the cultivars for the traits examined. The highest average seed yield (4194.2 kg ha-1) and average linoleic acid content (65.09%) were found for BOSFORA. The highest average oil content ESNIEGARA (48.78%) and average oil yield respectively were obtained from ESNIEGARA (186.02 kg ha-1) and BOSFORA (182.93 kg ha-1) varieties and the highest average oleic acid content was obtained from 11TR077 variety (41.78%). The results of this study emphasized the importance of varieties in sunflower growing. BOSFORA and ESNIEGARA varieties had high yield and quality characteristics in the ecologies of a semi-arid climate.
AtıfScopus1WoS1OpenAlex1İncele - MakaleAçık Erişim2024Scopus SJRQ1A case study comparing seismic retrofitting techniques for a historically significant masonry building's minaret
Kiral, Adnan; Ergün, Mustafa; Tonyali, Zeliha; Artar, Musa; Şentürk, İdris
Historical masonry structures are extremely susceptible to earthquakes due to their characteristic features. Seismic performance and corresponding damage patterns vary between these buildings. Even though the main structure was undamaged, many minarets suffered damage or collapsed due to the transmission of large forces from the main mass to the minaret and the abrupt changes in cross-section due to the geometry of the minaret. This study uses an ancient masonry mosque as a case study, whose minaret and main building are constructed as a single structure. The mosque's minaret under seismic excitation is the focus of this study. The adopted model is called Alaeddin Bey Mosque in Muş, Türkiye. The seismic performance assessment of the minaret, considering various retrofitting options, is mainly based on four critical parameters: base shear, acceleration, displacement, and maximum tensile forces in all three dimensions. The analyzed retrofitting methods include base isolation located in the basement of the mosque, viscous dampers placed only in the upper part of the minaret, Carbon Fiber-Reinforced Polymer fabric fitted to only the minaret, and steel plates applied to only the minaret. Representative structural models of the mosque have been modelled with SAP2000 software. The main novelty of this study is the use of viscous dampers in the minaret. It is the first time a design methodology has been introduced for viscous damper applications in minarets. This methodology aims to prevent local damage to the minaret due to the forces generated by the dampers, while also considering the constraints of limited internal space within the minaret. The finding of this study shows that viscous damper application yields significantly better results compared to the application of Carbon Fiber-Reinforced Polymer fabric and steel plates. However, although base isolation reduces the tensile stress values throughout the entire mosque to levels well below the material's strength, viscous damper application in the minaret significantly reduces tensile stresses only in the minaret. As a result, viscous dampers are recommended for damage reduction in the minaret only. Otherwise, base isolation should be considered for reducing stress values throughout the entire mosque including the minaret. This study contributes towards the development of new seismic retrofitting methods for historic masonry buildings ‘minaret.
AtıfScopus26WoS26OpenAlex24İncele - MakaleAçık Erişim2025Scopus SJRQ1Optimization of Hemp Seed (Cannabis sativa L.) Protein Extraction and Glycation Conditions by Response Surface Methodology: Physicochemical, Functional, and Thermal Characteristics
Yüzer, Elvan; Kutlu, Naciye; Yüzer, Mustafa Onur
In this study, first, optimization using the response surface method was implemented to obtain the highest yield of protein isolate from defatted hemp seed under different extraction conditions. Optimum extraction conditions were determined with 0% salt concentration, 12 pH value, and 49°C temperature. The protein isolate produced under optimum conditions was subjected to the glycation process, and the glycation conditions were also optimized. The optimum conditions for glycation were determined as a protein isolate: sugar ratio of 1.6:1, temperature of 60°C, and time of 90 min, providing the most suitable glycation degrees and browning indices. There was no statistical difference between the glycated protein isolate obtained under these conditions and the nonglycated protein isolate in terms of emulsifying activity index and emulsion stability index. For total phenolic–flavonoid compounds and antioxidant activity, the sugar complex caused a decrease in these values. In addition, there was a high positive correlation between bioactive compounds. SEM micrographs showed relationships between hemp seed protein isolate and sugar, and these interactions led to a spongy three-dimensional microstructure. When the FTIR results were analyzed, the glycated isolate had stronger absorption at 3300–3200 cm−1 compared to the nonglycated isolate. In conclusion, this study reports important findings in terms of functional and characteristic properties of how monosaccharides affect glycation.
AtıfScopus1WoS1İncele - MakaleYalnız künye2024A Comparative Study on the Bioactivity and Mineral Content of Different Grapevine (Vitis vinifera L.) Leaves Cultivated in Türkiye
Yildiz, Hilal; Cakir, Ozlem; Cakiroglu, Kubra; Karatas, Neva
The mineral composition, total phenolic content, radical scavenging, and antibacterial activity of 17 Vitis vinifera L. leaves obtained from vineyards in northeast Türkiye were investigated in this study. The antibacterial activities of grapevine leaf extracts were investigated by the disk diffusion method against five bacterial strains, and all leaf extracts showed inhibitory activity on both Bacillus cereus and Staphylococcus aureus. The radical scavenging activity of grapevine leaf extracts was evaluated using the DPPH (2,2-diphenyl-1-picryl hydrazyl) and ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid) assays. The ‘Gineş’ cultivar had the highest level of radical scavenging activity, while the ‘Ciklap’ cultivar had the lowest. The total phenolic content of leaf extracts was in the range of 172.66–483.33 µg GAE/mg DW. Grapevine leaf extracts were examined in terms of 15 different elements. The most abundant element in varieties of grapevine leaves was potassium, and its concentration varied between 5208.83 and 13,586.49 mg/kg. The results indicated that V. vinifera L. leaves had strong antioxidant and antibacterial activity, and the varieties of grapevine had a significant impact on these parameters (p < 0.001). Mineral and trace element contents were also significantly affected by cultivars (p < 0.05).
AtıfScopus6WoS5OpenAlex6İncele - MakaleYalnız künye2024Scopus SJRQ2The effect of loneliness on fear of aging: Mediated by social support
Akeren, Zahide; Akeren, Ihsan
The study aimed to examine the relationships between loneliness, perceived support and fear of old age, to determine how they differ according to some socio-demographic variables and of loneliness to reveal the mediating role of perceived social support in the effect on fear of old age. In the descriptive cross-sectional study conducted between November 2023 and January 2024, the Loneliness Orientation Scale (LOS), Multidimensional Perceived Social Support Scale (MSPSS) and Fear of Old Age Scale (FOS) were used. Correlational analysis was used in the analysis of data collected from 611 participants aged 18–65 with two-stage sampling, T-test and ANOVA were used in the comparison of means, and the Hayes’ PROCESS macro was used to determine the mediating role of perceived social support. Women, singles, young people, those with low education and income fear old age more. There is a positive correlation between loneliness and fear of aging, and a negative correlation between these two and perceived social support. As a result, perceived social support is a partial mediator in the effect of loneliness on fear of old age and it should be considered as an effective source in reducing fear of old age.
AtıfScopus1WoS1OpenAlex2İncele - MakaleYalnız künye2022Scopus SJRQ3Comparison of Statistical Methods to Graphical Method in Precipitation Trend Analysis, A Case Study: Coruh Basin, Turkey
Hırca, Tuğçe; Eryılmaz Türkkan, Gökçen
It is a known fact that the precipitation characteristics will become irregular as a result of climate change resulting from global warming. Trend analysis is one of the most effective methods of observing the effects of climate change on precipitation. This study compares the changes in precipitation with traditional trend analysis methods and graphical method (divided into subcategories using the Z-Score Index). Some preliminary analyzes (missing data estimation, homogeneity check, autocorrelation, and removal of the autocorrelation), which are lacking in many studies in the literature, have been performed. In this context, the monthly total precipitation data of the precipitation stations belonging to the Coruh Basin, one of the most important basins of Turkey, for the period 1972–2011 were used. As a result of the study, it was determined that all the stations’ data were homogeneous, and 92% of them were at the Class A level. While 100% trend is determined in Innovative Trend Analysis in total annual precipitation, this rate was just 40% at Mann–Kendall and Spearman's rho at 95% confidence. An increasing trend was determined in the “high” group of total spring precipitation at all stations.
AtıfScopus5WoS4OpenAlex5İncele - MakaleAçık Erişim2024Scopus SJRQ1Simpler Reference-Plane-Invariant Method for Permittivity Extraction of Medium- or Low-Loss Dielectric Samples Using One-Port Measurements
Cem Hasar, Ugur; Ali, Husain; Kaya, Yunus; Stoyanov, Ivaylo
A microwave method is devised to extract relative complex permittivity (ϵr) of medium- or low-loss dielectric samples. It is simpler, non-iterative, reference-plane-invariant (RPI), and applicable for one-port waveguide measurements with short-circuit termination only. Besides, since it uses short-circuit termination reflection-only measurements, it is free from Fabry-Pérot resonances. Permittivity measurements of polyvinyl chloride (PVC) and polypropylene (PP) are performed at X-band (8.2-12.4 GHz) to examine the performance of the proposed method considering different scenarios involving inaccurate information of sample location in the cell and inaccurate knowledge of the sample thickness. Repeatability analysis is carried out to analyze the performance of the proposed method against other similar methods in the literature.
AtıfScopus6WoS5İncele
