Yayınlar
Koleksiyondaki öğeler
- MakaleYalnız künye2021Scopus SJRQ2Smart airport: Evaluation of performance standards and technologies for a smart logistics zone
Göcxmen, Elifcan
Owing to the current context of Industry 4.0, the importance of smart technologies in airport systems have increased substantially. State-of-art applications for transportation planning incorporating baggage services, routing, security, and safety are an evolving domain for both practitioners and researchers dealing with aviation applications. In this context, this paper seeks to answer these questions: Which standards are aimed at a smart airport to make the transportation planning sound? Which propositions are made based on the obtained prioritized standards? This study deals with standards including Environmental Effects, Docking & Navigation, Object Detection & Protection, Communications & Integration, and Terminology using a practical decision support system based on an analytical hierarchy process (AHP) and fuzzy inference system (FIS). Computational results reveal that the Object Detection & Protection standard has an effect on a safe and smart system. To give an overview of this standard for a smart logistics zone (SLZ), an architecture of autonomous robot units and a baggage handling system is proposed in this study. The suggested approach analyzes the obstacle photos obtained by cameras and allows the end-user to control the calculations visually. This research could provide advice to airport planners about smart policies and improving operations.
AtıfScopus25WoS10OpenAlex26
İncele - Kitap BölümüYalnız künye2022Evaluation of teachers' digital competencies in the digitalization process in educational organizations
Gündüzalp, Seda; Yaraş, Zübeyde
The education process has started to go beyond the traditional patterns with topics such as new teaching environment designs blended with technology, digital native learners, and the prominent competencies of the 21st century. At the center of these concepts, which have begun to transform education, teachers are in an important position that ensures the continuation of education system. In education systems changed by technology, it is known that teachers' digital competencies will affect the success of learners. Teachers who can be digitally competent will be more active in managing the process more effectively in the education of digital native generations. As the difficulties faced by teachers who are not digitally competent in the changing teaching process with the effect of technology will bring new problems for the education process, it is important to determine the digital competence levels of the teachers and to create action plans and policies. In this chapter, it is emphasized what the digital competencies of teachers are and why teachers should have digital competencies. The education process has started to go beyond the traditional patterns with topics such as new.
AtıfScopus1OpenAlex2İncele - MakaleYalnız künye2023Scopus SJRQ3ENTROPY ANALYSIS OF HYBRID NANOFLUID FLOW OVER A ROTATING POROUS DISK: A MULTIVARIATE ANALYSIS
Prakash, J.; Tripathi, Dharmendra; Akkurt, Nevzat; Shedd, Tim
This article discusses the flow of a time-dependent biviscosity hybrid nanofluid boundary layer across a rotational permeable disk with effects of magnetic field and thermal radiation, and the subjective and quantitative transfer of heat flow. In the classic Von Karman issue, nanofluids comprising volume fractions ofAg-MgO/60% water and 40% ethylene glycol are considered instead of Newtonian regular fluids. The governing equations are transformed nonlinear ordinary differential equations using Von Karman transformations. The equation for the generation of entropy is calculated as a function of velocity and temperature gradient. This equation is made nondimensional by adding geometric and physical flow field-dependent parameters. The velocity profiles in the radial, tangential, and axial directions, as well as the axial pressure gradient, nanoparticle temperature distribution, local skin friction, Nusselt number, and Bejan number, are calculated by using MATLAB bvp4c. The multivariate analysis is implemented in the numerical results of the Nusselt number. A rotation parameter is generated by the spinning phenomena, which regulates the disk’s movement. Increasing the rotation of the disk causes fluid velocity to accelerate in both the radial and cross-radial directions, while contrasting phenomena can be noticed in the axial velocity of the flow. The temperature and wall shear stress of a nanofluid both rise with the disc’s Brinkman number and the volume fraction of nanoparticles. Increasing the thickness of the thermal boundary layer raises the axial pressure gradient. Entropy measured by the Bejan number Influences the magnetic field and the Biot number. Physical parameters presented in this article may be used to optimize the system’s performance. A magnetic rotating porous disk drives could be used in nuclear space propulsion engines and in heat transfer augmentation in thermal management and renewable energy sources.
AtıfScopus6WoS6OpenAlex6İncele - MakaleAçık Erişim2022Scopus SJRQ1Effectiveness of the training provided to healthcare professionals in Turkey to recognise the symptoms and risks of child abuse and neglect
Cevik Durmaz, Yadigar; Tuncer Coban, Pelin; Eseroglu Soylemez, Tugba; Aktas, Hakki
Healthcare professionals have a significant role to play in the early diagnosis of child abuse and neglect (CAN), which is important in terms of protecting children's health. The study aimed to measure the change in the participants' level of diagnosing the risks and symptoms of CAN before and after the training by providing a training program to healthcare professionals including the signs of CAN, symptoms and procedures to be followed in this case. All healthcare professionals working in a State Hospital and Family Health Centers in Tunceli, Turkey, and who volunteered to participate in the study were included in the study (n = 125). The data were collected before and after the training by using the Personal Information Form and The Diagnosis Scale of the Risks and Symptoms of Child Abuse and Neglect (DSRSCAN). 39 participants (31.2%) reported that they had previously suspected CAN, and 35 (28%) stated that they had encountered CAN before. The mean DSRSCAN score of the healthcare professionals included in the study before the training was 3.38 (lowest =2.37, highest =3.55), while after the training, it went up to 3.60 (lowest =2.76, highest =5.00), and the difference between the pre-training and post-training DSRSCAN scores was determined to be statistically significant (p < 0.001). It was determined that when healthcare professionals were trained on CAN, their awareness could be further strengthened. Hence, training programs for healthcare professionals on diagnosing and reporting CAN should be updated and increased.
AtıfScopus14WoS15OpenAlex18
İncele - MakaleYalnız künye2021Scopus SJRQ2The Effect of the Transtheoretical Model Based Walking Exercise Training and Follow-Up on Improving Exercise Behavior and Metabolic Control in Patients with Type 2 Diabetes
Kaplan Serin, Emine; Citlik Saritas, Seyhan
This study aims to determine the effects of transtheoretical model-based walking exercise training and follow-up on improving exercise behavior and metabolic control in patients with type 2 diabetes. This randomized controlled trial was conducted as a pre-test and post-test experimental model with 76 intervention and 76 control individuals. The intervention group received the transtheoretical model-based exercise training. Data were collected using patient identification form, transtheoretical model scales, pedometer and metabolic outcomes. Data were analyzed by Chi square, two-way ANOVA, Mauchly’s, Greenhouse-Geisser, Friedman, and McNamer test. The overall score means for the exercise change processes, decision-making balance and self-efficacy scales increased compared to the pre-test (p <.001). The mean HDL increased from 41.39 ± 10.35 to 49.18 ± 11.58, and average number of steps per day increased from 3264.31 ± 1933.03 to 5639.37 ± 2317.01. Consequently, this difference between the groups was significant (p <.05).
AtıfScopus11WoS8OpenAlex9İncele - MakaleYalnız künye2021Scopus SJRQ3Comparison of heat transfer and condensation on the walls of buildings constructed with iron profiles versus other classic models
Kahraman, Gökhan
This study aims to present the evaluation of the thermal performance and the amount of condensation on the walls of a building with iron profiles under steady-state conditions. Elazig, situated in the east part of Turkey, was chosen for fieldwork. In this region, minimum average temperature is around 1°C during winter. Calculations are made in a real wall model and three different wall model scenarios. Estimated advantages and disadvantages of these have been investigated. Heat transfer and condensation amount are taken as variables. In four different building component models, the required amount of energy during the heating period is calculated month by month. Calculations reveal the resistance of the wall without application of insulation material with iron profile is higher than of the other three wall types. The wall built with betopen and iron profile saves 37.5% more energy than the wall with bricks. When the iron-profiled wall model is compared with the insulated brick wall, it is observed that energy savings are similar, but calculations show condensation begins on the iron profile wall. Iron profile buildings become popular increasingly in rural areas. As a result of this study, it is observed that iron profile buildings are advantageous in terms of energy saving compared to other building component models. However, condensation is inevitable in wall components of iron profile buildings and so the damage in the buildings is more than just a disadvantage, it is an irreversible result.
AtıfScopus2WoS3OpenAlex3İncele - MakaleAçık Erişim2022Scopus SJRQ1SBOX-CGA: substitution box generator based on chaos and genetic algorithm
Artuğer, Fırat; Özkaynak, Fatih
What makes artificial intelligence techniques so remarkable in the field of computer science is undoubtedly their success in producing effective solutions to difficult computational problems. In particular, metaheuristic optimization algorithms are a unique example of using artificial intelligence techniques to generate approximate solutions to problems that cannot be solved in polynomial time, called NP. Obtaining a substitution box (s-box) structure that will satisfy the desired requirements in cryptography is an example of these NP problems. In the literature, it is a hot topic to optimize the s-box structures obtained from chaotic entropy sources with heuristic algorithms to improve their cryptographic properties. The study with the highest nonlinearity value (110.25) based on optimization algorithms to date has been published in 2020. In this study, a method with a higher nonlinearity value than the algorithms previously proposed in the literature is developed. It has been shown that the nonlinearity value can be increased to 111.75. These results will be a basis for new research on the chaos-based s-box literature and will motivate new studies to develop alternative optimization algorithms in the future to obtain s-box structures based on the random selection equivalent to the AES s-box.
AtıfScopus47WoS35OpenAlex49İncele - MakaleAçık Erişim2021Scopus SJRQ2Preservice teachers' nomophobia levels, sense of loneliness and adjustment to college life
Çevik-Durmaz, Yadigar; Yalçinkaya-Önder, Eylem; Timur, Serkan
Purpose: The aim of this study was to investigate whether preservice teachers' nomophobia levels, sense of loneliness and adjustment to university life vary based on their demographic characteristics. Additionally, regression analyses were carried out to determine whether their sense of loneliness, nomophobia levels, and adjustment to university life were predictors of each other. Design and Methods: In this quantitative study, the cross-sectional survey research model was used. A total of 234 preservice teachers, 65 of whom were studying at the elementary mathematics department, 81 of whom were studying at the preschool education department, and 88 of whom were studying at the science education department, participated in this study. Independent-samples t test, one-way analysis of variance (ANOVA) and simple linear regression analyses were used to analyze the quantitative data. Findings: The main conclusions from this study were that (a) the students with the highest sense of loneliness were the students of the elementary mathematics department, the students with the highest level of nomophobia were the science education students, and the students who adjusted the most to university life were the preschool education students. (b) There were no significant differences between the 1st and 2nd year preservice teachers in terms of their sense of loneliness, nomophobia levels, and adjustment to university life. (c) There were statistically significant differences between the mean total nomophobia scores of the male and female students in favor of the females especially in the “losing connectedness” and “not being able to access information” subscales of nomophobia. (d) A statistically significant difference was found between the preservice teachers whose mothers were high school and university graduates in terms of their academic adjustment in favor of the preservice teachers with mothers who had university degrees. (e) The preservice teachers, who stated that their relationship with their family was very good, had higher levels of sense of loneliness, mobile phone addiction, and adjustment to university life than the others. The results were statistically significant in all total scores of the loneliness scale and dimensions except for the dimensions of nomophobia. (f) The students who were hopeful for the future had a high sense of loneliness and adjustment to university life. It was also determined that the students who were desperate for their future had high mobile phone addiction levels. Apart from nomophobia and its dimensions and the social adjustment dimension of university life, statistically significant differences were found between the hopeful and hopeless students in terms of their sense of loneliness and adjustment to university life. (g) Statistically significant mean differences were found between the students who were generally satisfied with and those that were not satisfied with their life in terms of their sense of loneliness and adjustment to university life with its all dimensions in favor of the satisfied ones. (h) The preservice teachers who lived alone at home had a higher sense of loneliness and better adjustment to university life. It was also noteworthy that the students living in dormitories had higher nomophobia levels than the others. (i) A linear relationship was found between the students' sense of loneliness and adjustment to university life, and sense of loneliness was a significant predictor of adjustment to university life. Practical Implications: Determining students' nomophobia levels, sense of loneliness, and adjustment to university life would be beneficial in bringing students who have difficulty adapting to new living environments into social life.
AtıfScopus10WoS7OpenAlex16İncele - MakaleAçık Erişim2022Scopus SJRQ2Prangos munzurensis (Apiaceae), a new species from East Anatolia, Turkey
Lyskov, Dmitry; Duran, Ahmet; Paksoy, Mehmet Yavuz; Samigullin, Tahir
A new species, Prangos munzurensis (Apiaceae), is described and illustrated from Tunceli Province, Eastern Turkey. The new species is related to Prangos heyniae, P. abieticola, and P. denticulata and differs from them in the number of rays, length of bracts, indumentum of petals, ultimate segments of leaves, stylopodium features, fruit morphology and anatomy, and distributional range. It also differs from P. ferulacea in presence of furrows between blocks of inner mesocarp, number of umbel rays, and puberulous petals. A comprehensive description of the morphological and carpo-anatomical features, photographs, and data on the geographical distribution, habitat and ecology, and conservation status are also provided. In addition, P. munzurensis is recognized as a separate species by molecular analysis of nrITS/ETS.
AtıfScopus2OpenAlex2İncele - MakaleAçık Erişim2021Scopus SJRQ3Epiphytic Bryophyte Communities of Forests Dominated by Alnus glutinosa (L.) Gaertner in Altindere Valley National Park (Trabzon, Turkey)
Alataş, Mevlüt; Batan, Nevzat; Ezer, Tülay; Özdemlr, Turan; Erata, Hüseyin
The epiphytic bryophyte communities of the Altindere Valley (Macka, Trabzon, Turkey) were studied. A total of 59 releves, taken from living tree trunks in different vegetation periods of 2018 and 2020, were analysed according to the Braun-Blanquet methodology, and the releves were also ordinated and classified using the Detrended Correspondence Analysis (DECORANA) and the Two-Way Indicator Species Analysis (TWINSPAN). As a result of the analyses, Alleniella besseri-Leucodontetum immersi as. nov., Plagiomnio undulati-Raduletum lindbergianae typicum and P.-R. leucodontetosum sciuroidis subas. nov. (Neckerion complanatae) were described and characterised as a new epiphytic. Mnietum cuspidati, Homalothecio sericei-Neckeretum besseri and Brachythecietum populei-isothecietosum alopecuroidis were also described as new to Turkey, whereas Brachythecietum populei typicum was recorded for the second time in Turkey.
AtıfScopus7OpenAlex6İncele - MakaleAçık Erişim2023Scopus SJRQ2Paleoseismology of the Ganos segment; the western extend of the North Anatolian Fault (Turkey)
Aksoy, Murat Ersen; Meghraoui, Mustapha; Ferry, Matthieu; Çakir, Ziyadin; Uçarkuş, Gülsen; Sançar, Taylan; Altin, Mehmet Uğur
The Ganos fault that ruptured on 9 August 1912 (Mw: 7.4) is the westernmost inland segment of the North Anatolian fault (NAF). Here, the Ganos fault is bounded at its two tips with offshore faults segments, in the Sea of Marmara to the east and the Gulf of Saros to the west in the North Aegean Trough. Therefore, the paleoseismology of the 45-km-long inland fault is of importance to the seismic hazard analysis related to offshore active faults and in particular for the seismic gap in the Marmara Region. Earlier studies have established an earthquake chronology for the western and eastern inland tips of the Ganos fault. Here, we extend the paleoseismic studies toward the central segment. Three trenches at Yörgüç have revealed evidence for two faulting events, possibly post-1669 CE ±30 years, which can be correlated to the 1659 or 1766, and the 1912 historical earthquakes. At Yeniköy, we determined an offset of 46 ± 1 m and 47 ± 1 m on a stream channel and a ridge-crest, respectively. In two trenches we determined two faulting events for the last 1000 years and seven events for the last 3500 years. In trench T5, the base of the displaced stream channel provides a calibrated date of 829–591 BCE. Using the 46 ± 1 m right-lateral displacement, we calculate a slip rate of 16.9 ± 0.7 mm/year for the last 2732 ± 119 years. A combined analysis with earlier paleoseismic studies on the Ganos fault suggests that the historical earthquakes of 1912, 1766b or 1659, 1354 or 1343a, and 1063 ruptured the entire inland fault section. In such a case, the recurrence interval for this section of the NAF corresponds to 283 ± 81 years. Combining earlier estimations, we suggest an average slip rate of 17.1 ± 0.9 mm/year for the last 2700 years and observe a characteristic slip behavior of 4.5 to 5 m per event for this section of the North Anatolian plate boundary fault.
AtıfScopus1OpenAlex2
İncele - MakaleAçık Erişim2021Scopus SJRQ2Chemical compositions, radical scavenging capacities and antimicrobial activities in seeds of satureja hortensis l. And mentha spicata l. subsp. spicata from turkey; [Composições químicas, capacidades radicais eliminadoras e atividades antimicrobianas em sementes de satureja hortensis l. E mentha spicata l. subsp. spicata da turquia]
Emre, İ.; Kurşat, M.; Yilmaz, Ö.; Erecevi̇, P.
The present study determined some biological compounds, radical scavenging activity and antimicrobial capacity in seeds of Satureja hortensis L. and Mentha spicata L. subsp. spicata. Alpha-linolenic acid (C18:3 n3) has been found to be the major polyunsaturated fatty acid of Satureja hortensis L. (66.24 ± 1.24%) and Mentha spicata L. subsp. spicata (48.17 ± 1.01%). Linoleic acid (C18:2 n6) is identified as the second major polyunsaturated fatty acid in the present study and oleic acid (C18:1 n9) is determined as the major monounsaturated fatty acid. Current study showed that Satureja hortensis L. and Mentha spicata L. subsp. spicata have low levels of saturated fatty acids. It has been demonstrated that ergosterol (263.1 ± 2.14 µg/g), stigmasterol (39.07 ± 0.91 µg/g) and beta-sitosterol (14.64 ± 0.49 µg/g) have been found in Mentha spicata L. subsp. spicata, while ergosterol (69.41 ± 1.75 µg/g) and beta-sitosterol (19.81 ± 1.14 µg/g) have been determined in Satureja hortensis L. Also, this study determined that Satureja hortensis L. and Mentha spicata L. subsp. spicata have low lipide-soluble vitamin content. Furthermore, it has been found that Satureja hortensis L. contains naringenin (612.57 ± 2.57 µg/g), morin (86.97 ± 1.12 µg/g), quercetin (22.87 ± 0.75 µg/g), and kaempferol (20.11 ± 0.94 µg/g) while naringenin (135.91 ± 1.91 µg/g), naringin (61.23 ± 2.15 µg/g) and quercetin (47.51 ± 1.17 µg/g) have been detected as major flavonoids in the seeds of Mentha spicata L. subsp. spicata. The results of the present study suggest that methanol extracts of Satureja hortensis L. and Mentha spicata L. subsp. spicata have significant free radical scavenging activity. The present results revealed that Satureja hortensis L. and Mentha spicata L. subsp. spicata showed major activity against gram-positive and gram-negative microorganisms, fungi and yeast.
AtıfScopus14OpenAlex18İncele - MakaleYalnız künye2022Scopus SJRQ1Numerical evaluation of convective heat transfer properties of two-dimensional rotating PCM melt in the unilaterally heated rectangular container
Liu, Dinghai; Xie, Kai; Zhang, Hui; Qiang, Yujie; Yang, Di; Wang, Zhaoxiao; Zhu, Lidong; Akkurt, Nevzat; Du, Yanping; Shen, Meng
This paper carried out numerical investigations on the flow and heat transfer characteristics of a phase change with two-dimensional rotation of the three-dimensional paraffin (RT -27)-filled rectangular encapsulated container (PCM-REC) in space. A three-dimensional transient numerical heat transfer model was established and the enthalpy method was used to simulate the solid-liquid phase transition process and the flow evolution at the PCM interface. In this paper, the solid-liquid interface distribution, temperature distribution and melting time of PCM in PCM-REC heated at a constant temperature on one side were compared when rotated at different angles (0°, arctan (0.4), 2arctan (0.4) and 90°) along the heating direction and vertical heating direction. Results demonstrated that the peak value of maximum natural convection velocity increased from 0.0072 m/s to 0.0184 m/s with increasing radial height when PCM-REC was rotated in vertical heating direction. When PCM-REC was rotated in two dimensions by the same angle, the melting time was fastest when γ was an obtuse angle, and with the increase of the obtuse angle, the melting time shortened from 17 min to 6 min; when γ was an acute angle, the melting time was slowest, and with the decrease of the acute angle, the melting time lengthened from 49 min to 288 min.
AtıfScopus35OpenAlex40İncele - MakaleYayıncıda açık erişim2022Scopus SJRQ2A biomechanical study: Comparison of three different implant options in high Tibial osteotomy
Key, Sefa; Demir, Sukru; Aydın, Oğuz; Say, Yakup; Erten, Mehmet
Background: Many implant options could be preferable for fixation after osteotomy in varus knee medial compartment arthrosis. Due to usage characteristics, it is important to compare the biomechanical properties of them. For this purpose, we aimed to examine three different implant types biomechanically in our study. Methods: Ovine tibiae undergoing medial open-wedge high tibial osteotomy were fixed in vitro with three different implants using an angular wedge plate, a metal block plate and an external fixator system. The fixed ovine tibiae were subjected to axial tensile, axial loading and three-point bending tests in a test machine. All biomechanical tests were repeated five times, the maximum and minimum values were ignored, and the average values of the remaining three test results were taken into account. The test results were interpreted after converted into force-elongation curves in Trapezium-X software. Findings: Biomechanical test results revealed some differences between implant types. While the metal block plate had the highest axial tensile strength value, it was the fixation group showing the lowest strength in axial load tests. The used fixator system was the highest strength in axial load tests and the lowest strength in axial tensile tests. Interpretation: Considering the clinically significant forces related to the biomechanical stability of the three different implants used for high tibial osteotomy, the fixator system would appear to be slightly superior, although it should be noted that torsional forces, as well as parameters that could change in living tissue, might affect the results.
- MakaleAçık Erişim2021Scopus SJRQ2Effects of Aging on Magnetic and Thermal Characteristics of NiMnCoSn Magnetic Shape Memory Alloys
Kök, Mediha; Aydoğdu, Kumruya; Kanca, M. Sait; Qader, Ibrahim Nazem; Öner, Ecem; Coşkun, Meltem
Heusler shape memory alloys are important for many applications due to their typical magnetic and shape memory behaviors. In this study, a Ni50Mn36Sn12Co2 (at.%) alloy was manufactured by arc-melting technique, then the ingot cooled to ambient temperature in the natural atmosphere. Three different temperatures, including 500 °C (773 K), 700 °C (973 K), and 900 °C (1173 K), was selected for aging the samples cut from the main ingot. The impact of aging on the crystalline; microstructure; caloric; and magnetic properties of the alloys were investigated through x-ray diffraction (XRD); scanning electron microscope; differential scanning calorimetric (DSC), differential thermal analysis, and thermal gravimetric (TG); and physical property measuring system was investigated, respectively. The aging in different temperatures led to the shift DSC curve, such that the martensitic phase transformation temperatures of the sample aged at 773 K increased, however, the transformation at 973 and 1173 K decreased compared to the as-casted alloy. The different phase transformation behavior showed that the alloy aged at 773 K has the maximum elastic energy, enthalpy and entropy change compared to the reset of samples, on the other hand, its crystallite sized obtained from XRD analysis comparably diminished. Besides, the TG analysis revealed that the mass gain almost occurs at a temperature above 773 K, therefore the magnetization of the alloys aged at 973 and 1173 K decreased due to a thin oxide layer formed on the surface of the alloys.
AtıfScopus5WoS5OpenAlex7İncele - MakaleYalnız künye2021Scopus SJRQ1Bacterial crack healing in metakaolin based geopolymer mortars
Yılmazer Polat, Berivan; Uysal, Mucteba
Geopolymer mortars have emerged as an environmentally friendly binding alternative to conventional cement. However, the gaps in their structure and early cracks reduce their service life. There are various bacterial healing studies in the literature that have been conducted on cemented mortar cracks. Nevertheless, the present study focuses on the healing of metakaolin based geopolymer mortar cracks. For this purpose, mortars with different molarities were prepared with two different endospore forming methods that did not require encapsulation or mixed chemical processes for the bacterial crack repairs on the geopolymer mortars. These mortars were then left in different healing environments with crack damage. The samples were tested using physical, optical and internal structure analyses. As a result, the cracks were improved by reducing the amount of gaps in the samples. The results showed that it is possible to bacterially repair early cracks in new generation ceramic materials with alkali-activated mortars and reduce the amount of gaps.
AtıfScopus41WoS35OpenAlex36İncele - Kitap BölümüYalnız künye2023Avalanche Risk Analysis by a Combined Geographic Information System and Bayesian Best-Worst Method
Konurhan, Zekeriya; Yücesan, Melih; Gul, Muhammet
The formation of avalanches is related to the land structure, climatic conditions, and snow cover. It is usually seen in mountainous and sloping terrains without vegetation. In Turkey, especially in Eastern Anatolia and the Black Sea Region, which have high elevations, avalanche events are observed. This study aims to perform a risk analysis by integrating the Bayesian Best-Worst method (BWM) and Geographic Information System (GIS) for Tunceli province, which is the scene of significant avalanche events. Bayesian BWM is a method that improves the original BWM by effectively integrating the preferences of multiple experts. In the study, 16 sub-criteria, such as elevation, slope, and the number of snowy days, were determined, and experts evaluated these criteria through questionnaires created. The weight of each criterion were calculated using the Bayesian-BWM. By integrating the criteria weights from the Bayesian-BWM model into GIS, the risky places for natural avalanche disasters in Tunceli province were determined, according to which the risk in the northern part of the study area is identified as high.
AtıfScopus5İncele - MakaleAçık Erişim2023Scopus SJRQ1A comprehensive study on structural properties, photon and particle attenuation competence of CoNiFeCr-Ti/Al high entropy alloys (HEAs)
Sakar, Erdem; Guler, Omer; Alım, Bünyamin; Say, Yakup; Dikici, Burak
It is well known that high entropy alloys (HEAs) have a wide range of potential applications as radiation shielding due to their superior properties. The CoNiFeCr-Ti/Al compositions were chosen for their low cost as HEA in this study. The HEAs were successfully produced using the mechanical alloying (MA) method with equimolar CoNiFeCr, CoNiFeCrAl, and CoNiFeCrTi compositions. The production and structural properties of the alloys were investigated in detail. Besides, the photon and particle radiation shielding properties of the HEAs were calculated with the help of Phy-X/PSD, SRIM (10 keV-20 MeV), and ESTAR (10 keV-20 MeV) programs. The photon-matter interaction parameters were calculated in both specific photon energies emitted from 241Am, 133Ba, 109Cd, 60Co, 137Cs, 131I, and 22Na nuclides and a continuous energy range of 15 keV-15 MeV. The characterization of the alloys was investigated by using X-ray diffraction (XRD) and scanning electron microscopes (SEM) attached to an energy dispersive spectroscopy (EDX). It was found that the HEAs have a highly amorphous structure due to the selected production method. The crystal size of the alloys was calculated as 70, 35, and 20 nm for CoNiFeCr, CoNiFeCrAl, and CoNiFeCrTi, respectively. In terms of shielding properties, it has been determined that the produced HEAs have better shielding characteristics for photon and particle radiations than standard shielding concretes. In addition, the results demonstrated that CoNiFeCr alloy, which has the best shielding ability among the HEA alloys, can be used as a shielding material application requiring photon, electron, proton, alpha, and neutron radiations.
AtıfScopus30WoS32OpenAlex32İncele - MakaleYalnız künye2023Scopus SJRQ2Isolation, morphological identification, and xylanase characteristics of anaerobic gut fungi Neocallimastix from Anatolian wild goat
Kar, Bülent; Torcan, Berat
This study shows the morphological identification of anaerobic fungal strains isolated from fecal samples of goats inhabiting Turkey and the effects of various metal ions and chemicals on extracellular xylanase production. Three different anaerobic gut fungi isolated from wild goats in Turkey were identified as Neocallimastix spp. xylanase, cellulase, and lichenase production were tested in culture supernatants, and the maximum-specific activities were found as 560.42 ± 9.39, 159.70 ± 3.88, and 157.36 ± 3.83 (μmol/min/mg protein), respectively. While the optimum temperature range of exo-xylanases was found as 40–50°C, their optimum pH range was determined as 6.0–6.5. Xylanase activity decreased in metal ions and other chemical reactants based on dose. The metal ion that significantly inhibited xylanase activity was Fe+3. It was found that the ferric ions inhibited xylanase activity in all three anaerobic gut fungi by 30%–90% depending on molarity. On the contrary, the 1 mM concentrations of the Mn+2, Ba+2, Co+2, Cu+2, Sn+2, and Mg+2 metal ions and the ethylenediaminetetraacetic acid and β-mercaptoethanol reagents had a positive effect at rates in the range of 3%–92%. In conclusion, these findings demonstrate that anaerobic gut fungus has very stable fibrolytic enzymes that need to be separated, as well and the existence of a unique resource for industrial applications.
AtıfScopus3WoS3OpenAlex4İncele - MakaleAçık Erişim2021Scopus SJRQ2Drying of licorice root by novel radiative methods
Icier, Filiz; Ozmen, Duygu; Cevik, Mutlu; Cokgezme, Omer Faruk
In this study, licorice root was successfully dried using two different radiative dryers (Carbon fiber-assisted cabin drying-CFACD and infrared drying-ID), and their effects on some drying characteristics, quality properties, and energy-exergy efficiency were investigated. Page and Verma models were the best models describing the drying behavior of licorice root for CFACD and ID methods, respectively. ID protected total phenolic content (TPC) better than CFACD while the changes of color properties were higher for ID. Energy and exergy efficiencies of CFACD were 40.20 ± 0.20% and 31.87 ± 0.10%, respectively, while these values were 10.39 ± 0.33% and 9.99 ± 0.27% for ID, respectively. Practical applications: The radiative heating method has advantages such as shorter drying time, high-energy efficiency, and high heat transfer coefficient compared to convective drying methods. Infrared drying (ID) is known as the common energy efficient drying method for food materials while the information on the performance of other type of radiative carbon fiber assisted drying (CFACD) systems is limited. In this study, the use of carbon fiber assisted cabin dryer for drying of licorice was evaluated by comparing other radiative type infrared dryer. The drying characteristics of licorice samples having high amount of phenolic contents were compared both in terms of quality and energy performance characteristics of dryers. Energy and exergy efficiencies of CFACD were found to be higher than ID. In addition, more homogeneous temperature distribution and less color change were obtained in the CFACD process. It was determined that the CFACD process could be recommended for drying of licorice samples rather than ID.
AtıfScopus18WoS13OpenAlex15İncele
