Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Gul, Muhammet(102)
- Güler, Ömer(69)
- Akkurt, Nevzat(68)
- Tekin, H.O.(52)
- ALMisned, Ghada(49)
- Yucesan, Melih(49)
- Celik, Erkan(45)
- Zengin, Gokhan(40)
- Serdar, Osman(39)
- Kocabaş, Mehmet(37)
- Aslan, Naim(31)
- Baskonus, Haci Mehmet(31)
- Bulut, Hasan(31)
- Mete, Suleyman(31)
- Paksoy, Mehmet Yavuz(30)
- Kök, Mediha(27)
- Ince, Muharrem(26)
- Yildirim, Ozal(26)
- Özkul, İskender(26)
- Sulaiman, Tukur Abdulkadir(25)
- Topal, Murat(25)
- Guler, Omer(24)
- Serin, Faruk(23)
- Benzer, Fulya(22)
- Erten, Fusun(22)
- Alataş, Mevlüt(21)
- Güler, Seval Hale(21)
- Baykal, Duygu Sen(20)
- Taşgın, Yahya(20)
- Kutlu, Banu(19)
- Onat, Onur(19)
- Sahin, Kazim(19)
- Tanyol, Mehtap(19)
- Torğut, Gülben(19)
- Yildirim, Numan(19)
- Kahraman, Gökhan(18)
- Orhan, Cemal(18)
- Say, Yakup(18)
- Susam, Selim Orhun(18)
- Utku, Anıl(18)
Yayınlar
- MakaleAçık Erişim2020Scopus SJRQ3Synthesis of comb-type block copolymers by grafting through method: electrical properties and determination of activation energy via conductivity
Pıhtılı, Guzin; Demirelli, Kadir
Poly[Ɛ-CL-b-(MMA-comb-EMA)]comb-type polymers were synthesized by ATRP and Ɛ-caprolactone macroinitiator and macromonomer. Methyl methacrylate macromonomer was synthesized from acylation reaction of methacryloyl chloride with PMMA ended 7-hydroxy coumarin. The macroinitiator was prepared from the reaction of chlorine acetyl chloride P(Ɛ-CL). The synthesized polymers were characterized by FT-IR, 1H-NMR and 13C-NMR techniques. The average molecular weight and molecular weight distribution of polymers were measured by GPC method. Thermal properties of samples were studied by DSC/TGA techniques. Dielectric and Ac conductivity measurements were performed. Dielectric constant (ɛˈ), dielectric loss factor (ɛˈˈ) and conductivity behaviors of comb-type polymer were measured at room temperature between the frequency of 100–2000 Hz and over the temperature range 303–413 K at 1 kHz reported as compared with each other. Besides, their effects on the electrical properties by doping with EuCl3 for some of the comb copolymers were and were investigated. The activation energy (Ea) was calculated from conductivity. We reported it was determined that the (ɛˈ) and (ɛˈˈ) values decreased with increasing frequency. There are also many application areas for comb polymers for example; nanotechnology, medicine. The aim of this study is to synthesize comb-type copolymers in different compositions and to investigate their electrical properties.
AtıfScopus4WoS4OpenAlex4
İncele - MakaleYalnız künye2020Scopus SJRQ2The Effect of Progressive Relaxation Exercises on Pain, Fatigue, and Quality of Life in Dialysis Patients
Kaplan Serin, Emine; Ovayolu, Nimet; Ovayolu, Özlem
Patients receiving hemodialysis treatment may experience several symptoms at the same time, such as fatigue and pain. Progressive relaxation exercises (PRE) have been reported to have positive effect on the control of these symptoms. In this study, a randomized, controlled, and experimental study was conducted to examine the effect of PRE on pain, fatigue, and quality of life in hemodialysis patients; the study was carried out with 48 intervention and 48 control patients receiving treatment in the hemodialysis units of 2 hospitals. Data were collected by a questionnaire prepared by the researcher, which included questions about sociodemographic variables and the disease; Piper Fatigue Scale; Visual Analog Scale that measures pain severity; and SF-36 Quality of Life Scale. The results of study revealed that mean total fatigue score and mean pain score decreased in the intervention group after the application of PRE; whereas no change was observed in the control group (P <.05). It was also found that quality of life physical component mean score and mental component mean score increased in the intervention group after the application of PRE (P <.05).
AtıfScopus35WoS31OpenAlex44
İncele - MakaleAçık Erişim2020Scopus SJRQ2Sentiment classification within online social media using whale optimization algorithm and social impact theory based optimization
Akyol, Sinem; Alatas, Bilal
In recent years, social networks have become an important part of daily life and are becoming increasingly important. In this study, sentiment analysis or opinion mining, which is one of the most well-known social network analysis problems, is considered as an optimization problem for the first time. In the same way, for the first time, sentiment analysis is considered as a multi-objective problem. Whale Optimization Algorithm and Social Impact Theory based Optimization Algorithm, which are the current intelligent optimization algorithms, are adapted for the sentiment analysis problem. Furthermore, memory feature is integrated into Social Impact Theory based Optimization Algorithm in order to obtain effective results in this study. The obtained results from the proposed algorithms are also compared with thirty-three supervised learning algorithms within real IMDB, Polarity, and Amazon data sets. In order to evaluate the performance of the results; accuracy percentage, precision, recall, F-Measure, and MCC that are the five most commonly used measure in the literature are used. When the results are examined, it is observed that adapted metaheuristic optimization algorithms give more successful results in sentiment analysis problem.
AtıfScopus35WoS27OpenAlex43İncele - MakaleYalnız künye2020Scopus SJRQ2A comparative assessment of biological activities of Gundelia dersim Miller and Gundelia glabra Vitek, Yüce & Ergin extracts and their chemical characterization via HPLC-ESI-TOF-MS
de la Luz Cádiz-Gurrea, María; Zengin, Gokhan; Leyva-Jiménez, Francisco Javier; Fernández-Ochoa, Álvaro; Sinan, Kouadio Ibrahime; Cakilcioglu, Ugur; Babacan, Ebru Yuce; Mahomoodally, Mohamad Fawzi; Picot-Allain, Carene; Xiao, Jianbo
Plants from the Gundelia genus have been well appraised as both food and remedies. The members of the Gundelia genus are widely used as foods in several countries including Turkey. This study presents a comparative assessment of two poorly studied Gundelia species (G. glabra Miller and G. dersim Vitek, Yüce & Ergin). The effect of conventional (infusion, maceration, and Soxhlet extraction) and non-conventional (homogeniser and ultrasound assisted extraction) methods of extraction of bioactive secondary metabolites from the selected Gundelia species was also assessed. A total of 68 different compounds were detected by high-performance liquid chromatography coupled to electrospray ionization and time-of-flight mass spectrometry (HPLC-ESI-TOF-MS) technique. Non-conventional extraction techniques do not guarantee higher antioxidant activity. As such, G. dersim (91.27, 138.87, 182.28, and 125.65 mg TE [Trolox equivalent]/g dried extract, for 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), cupric reducing antioxidant capacity (CUPRAC), and ferric reducing antioxidant power (FRAP) assays, respectively).The highest α-glucosidase inhibition was recorded for the extracts obtained by ultrasonication. In the multivariate analysis, the extracts from Gundelia species were separated based on their biological activities. The presented findings could be one methodological starting point for designing novel products from two Gundelia species.
AtıfScopus12OpenAlex13İncele - MakaleYalnız künye2020Scopus SJRQ2Modeling and optimization of indigo carmine adsorption from aqueous solutions using a novel polymer adsorbent: RSM-CCD
Torğut, Gülben; Tanyol, Mehtap; Meşe, Zeynep
A novel adsorbent was prepared via the free radical copolymerization of 2-(dimethylamino) ethyl methacrylate (DMAEMA) and acrylonitrile (AN) using 2,2′-azobisizobutyronitrile (AIBN) as an initiator at 65 °C. Poly(DMAEMA-co-AN) was characterized by FT-IR, 1H-NMR, and SEM techniques. Its thermal properties were determined by TGA and DSC. The copolymer was used to remove indigo carmine (IC) from aqueous solutions. The optimum IC removal percentage was determined to be 99.53% with poly(DMAEMA-co-AN) of 0.10 g/100 mL, contact time of 31.37 min, 46.58 mg/L initial concentration of IC using a central composite design in response surface methodology. The high maximum adsorption capacity (196.07 mg/g) proved that poly(DMAEMA-co-AN) can be used as a promising adsorbent for the removal of IC from wastewaters.
AtıfScopus20WoS19OpenAlex21İncele - MakaleAçık Erişim2020Scopus SJRQ1Investigation of potential health risks in terms of arsenic in grapevine exposed to gallery waters of an abandoned mining area in Turkey
Topal, Murat; Arslan Topal, E. Işıl; Öbek, Erdal
In this study, potential health risks in terms of arsenic in grapevine exposed to gallery waters of an abandoned mining area in Turkey were investigated. The concentrations of arsenic were determined in roots, stems, and leaves. The translocation factors and bioconcentration factors were calculated. The highest arsenic concentration in the grapevine was determined as 539.4±27 mg/kg, for root. The arsenic concentrations in grapevine as follows: Root>Leaf>Stem. The estimated daily exposure followed an order for the male, female, and children: dermal<inhalation<ingestion<dietary. The non-carcinogenic and total hazard index values calculated for As were higher than 1. The risk of arsenic to be carcinogenic has been determined. The highest carcinogenic risk can be listed as dietary > ingestion > inhalation > dermal. In our study, calculated carcinogenic risk values in terms of dietary, inhalation, and ingestion are higher than 10−4-10−6. As a result, the highest cancer risk on human health was determined as a dietary intake of grapevine leaves according to the calculated carcinogenic risk values.
AtıfScopus20WoS19OpenAlex21İncele - MakaleYalnız künye2020Scopus SJRQ1The fabrication of bilayer polylactic acid films from cross-linked starch as eco-friendly biodegradable materials: Synthesis, characterization, mechanical and physical properties
Gürler, Nedim; Paşa, Salih; Hakkı Alma, M.; Temel, Hamdi
In this study, pure potato starch (PPS) was purified from waste potato residual to fabricate cross-linked bilayer materials with the casting method. Malonic acid (MA) was employed to get cross-linked material from PPS as PPS-MA. Then polylactic acid (PLA) was also implemented onto PPS and PPS-MA to produce bilayer materials as PPS-PLA and PPS-MA-PLA. The obtained these bilayer films were characterized by FTIR, XRD, and TGA. The mechanical and physical applications such as water vapor permeability, water uptake, moisture content, solubility, and opacity were investigated. The biodegradation calculations were also done by the process of composting. It has demonstrated that each application onto PPS increased the mechanical features. However, elongation wasn't seen during the breaking test of PPS and PPS-MA films, whereas the PPS-PLA and PPS-MA-PLA films demonstrated 9.34% and 10.14% elongation at break that substantiates the structural durability against rupture, fragmentation, and feeble. Furthermore, the water vapor permeability, water uptake, moisture content, and solubility decreased but the opacity has increased.
AtıfScopus70WoS64OpenAlex79İncele - MakaleAçık Erişim2020Scopus SJRQ1Automated invasive ductal carcinoma detection based using deep transfer learning with whole-slide images
Celik, Yusuf; Talo, Muhammed; Yildirim, Ozal; Karabatak, Murat; Acharya, U Rajendra
Advances in artificial intelligence technologies have made it possible to obtain more accurate and reliable results using digital images. Due to the advances in digital histopathological images obtained using whole slide image (WSI) scanners, automated analysis of digital images by computer support systems has become interesting. In particular, deep learning architectures, are one of the preferred approaches in the analysis of digital histopathology images. The deeper networks trained on large amounts of image data are adapted for different tasks using transfer learning technique. In this study, automated detection of invasive ductal carcinoma (IDC), which is the most common subtype of breast cancers, is proposed using deep transfer learning technique. We have used deep learning pre-trained models, ResNet-50 and DenseNet-161 for the IDC detection task. The public histopathology dataset containing 277,524 image patches were used in our experimental studies. As a result of training on the last layers of pre-trained deep networks, DenseNet-161 model has yielded F-sore of 92.38% and balanced accuracy value of 91.57%. Similarly, we have obtained F-score of 94.11% and balanced accuracy value of 90.96% using ResNet-50 architecture. In addition, our developed model is validated using the publicly available BreakHis breast cancer dataset and obtained promising results in classifying magnification independent histopathology images into benign and malignant classes. Our developed system obtained the highest classification performance as compared to the state-of-art techniques and is ready to be tested with more diverse huge databases.
AtıfScopus297OpenAlex318İncele - MakaleYalnız künye2020Scopus SJRQ4Estimation of gillnet selectivity for shabbout (Arabibarbus grypus Heckel, 1843)
Yüksel, Fahrettin; Demirol, Ferhat; Gunduz, Fatih; Coban, Mehmet Zulfu
In this study, it was aimed to determine the selectivity properties of the gillnets used for Shabbout (Arabibarbus grypus Heckel, 1843) in Keban Dam Lake, Turkey. Experiments were carried out at 3 different stations of the dam lake using 5 monofilament gillnets with 40, 50, 60, 70, 80 mm nominal mesh size (bar length). A total of 510 target species between 38 and 79.2 cm in total length were caught in 47 catching trials. The select method was used to estimate the selectivity parameters. When the model deviations were compared, the lowest deviation (183.6104) was observed to be given by the lognor-mal model. According to this model, optimum catch lengths of nets which have 40, 50, 60, 70, 80 mm mesh size determined as 40.12, 50.15, 60.18, 70.21, 80.24 cm and their spread values 3.03, 3.79, 4.55, 5.30, 6.06 cm, respectively. The differences between the length frequencies of the fish caught by all nets were found to be significant according to the Kolmo-gorav-Smirnov test. Minimum catch size of Shabbout is notified as 45 cm in Turkey. According to results of this study, gillnets with 50 mm and above mesh size do not cause an overfishing on Shabbout stocks.
AtıfScopus3İncele - MakaleYalnız künye2020Scopus SJRQ4Development and application of a novel hybrid occupational risk assessment model
Gul, Muhammet
Occupational Risk Assessment (ORA) is so crucial for safety management in the weapons industry since numerous hazards may lead to human casualties. Therefore, occupational health and safety stakeholders suggest proactive approaches in reducing risks to an acceptable level. Therefore, this paper aims to develop a novel hybrid ORA model for the weapons industry. The approach merges TODIM with Fine-Kinney concept. Risk parameters used in traditional Fine-Kinney method are weighted by Fuzzy Analytic Hierarchy Process (FAHP). Then, hazards and associated risks are prioritised using the approach. As an illustration, the gun and rifle assembly line of a weapon factory is handled. The application is carried out to improve operational safety and protect employee health. From both theoretical and practice aspects, it contributes to the literature by handling the problem in an integrated style of Fine-Kinney, FAHP and TODIM and by improving overall safety level of the observed factory and by suggesting potential action plans.
AtıfScopus4İncele - MakaleAçık Erişim2020Scopus SJRQ2Synthesis, and antimicrobial and anticancer activities of sodium acrylate copolymers
Torğut, Gülben; Pıhtılı, Güzin; Erecevit Sönmez, Pınar; Erden, Yavuz; Kırbağ, Sevda
This study was designed to synthesize poly(sodium acrylate-co-N-isopropylacrylamide) via aqueous free-radical polymerization using the 2,2′-azobisisobutyronitrile initiator system at 60°C. The structural characterization of the copolymer was determined by Fourier-transform infrared spectroscopy. The polymer was synthesized in two different ratios, namely, poly(NaAc-co-NIPA1:1) and poly(NaAc-co-NIPA2:1), to investigate whether it affects their antibacterial–antifungal activities and anti-tumour effects. When the antimicrobial activities of different proportions of the copolymer extracts prepared with pure water were examined using the agar disc diffusion sensitivity test (at 120 μL: 10.8 mg/µL), it was observed that they had effect at increasing rates against all the bacteria, yeasts and dermatophyte fungi such as Staphylococcus aureus COWAN 1, Staphylococcus cohnii ATCC 29974, Bacillus megaterium DSM 32, Bacillus subtilis ATCC 6633, Escherichia coli ATCC 25922, Klebsiella pneumoniae FMC 5, Pseudomonas aeruginosa DMS 50071 SCOTTA, Candida albicans FMC 17, Candida glabrata ATCC 66032, Trichophyton sp. and Epidermophyton sp. The results of this study revealed that the obtained copolymers have significant effects on the treatment of diseases. In addition, the anti-tumour activities of the poly(NaAc-co-NIPA1:1) copolymer on human breast (MCF-7) and ovarian cancer (A-2780) cell line were specified and it was determined that high doses of the copolymer showed anti-tumour effects on both types of cancer cell lines. Also, this article reviews its antimicrobial and anticancer activities that will be of help for future scientists.
AtıfScopus3WoS3OpenAlex6İncele - MakaleYalnız künye2020Scopus SJRQ2An FMEA-based TOPSIS approach under single valued neutrosophic sets for maritime risk evaluation: the case of ship navigation safety
Başhan, Veysi; Demirel, Hakan; Gul, Muhammet
As in terrestrial facilities, safety is one of the most important issue in ships. Vessels navigating in many parts of the world face many different, tough and dangerous navigational risks. In this context, twenty-three fundamental risks which are frequently encountered in ship navigation were considered in this study and examined by an FMEA-based TOPSIS approach under single valued neutrosophic sets. Because of the lack of data in the literature, the opinions of the experts (Masters) who have many years of experience in the sector were taken. As a result of the study, extreme weather conditions, injury of crew, loss of input of sensory equipment (depth, gyro, speed etc.), struck by ropes, exposure to high speed machineries under high pressures, loss of maneuverability are very important among these risks. Considering these risks, corrective-preventive action plans and managerial implications for ship navigation have been presented. Consequently, the results of this study have an important warning and solution recommendation regarding ship navigation risks.
AtıfScopus123WoS96OpenAlex113İncele - MakaleAçık Erişim2020Scopus SJRQ3Age and growth of the lessepsian migrant lagocephalus spadiceus (Actinopterygii: Tetraodontiformes: Tetraodontidae) from the gulf of iskenderun, north-eastern mediterranean, turkey
Başusta, Asiye; Başusta, Nuri; Ozcan, Ebru Ifakat; Girgin, Hülya
Background. The population of Lagocephalus spadiceus (Richardson, 1845), one of the Lessepsian species that migrated from the Red Sea to the Mediterranean Sea through the Suez Canal, has been growing rapidly in Turkey in recent years. This situation poses a serious danger to fisheries and human health. There is little information about the biology of this species. The presently reported study permits a greater understanding of the age and growth characteristics of the pufferfish L. spadiceus from the Gulf of Iskenderun, north-eastern Mediterranean. Materials and methods. Samples were captured by commercial bottom trawlers at depths of 24–50 m during 9 trawling operations conducted during the fishing seasons between 2012 and 2013 in the Gulf of Iskenderun, northeastern Mediterranean. Age determinations were carried out using vertebrae. Images of vertebrae suitable for age determination were obtained with a dissecting microscope. The index of the mean percentage error (IMPE) was calculated to assess the precision of the age determinations between two independent readers. Growth parameters for all individuals were then determined by fitting observed and length-at-age data using the von Bertalanffy growth equation. In addition, the condition factor (CF) was determined. Results. A total of 1116 specimens (529 females and 587 males) were sampled, ranging from 6.7 to 34.0 cm in total length and from 4.30 to 557.64 g in weight. The female-to-male ratio was 1:1.1. Age determination was conducted using vertebral band counts. The age of the examined specimens ranged from 0 to 10 years. One female individual was determined to be 17 years of age (45.6 cm and 1269.0 g). The von Bertalanffy growth equations were Lt = 47.21[1 – e–0.116(t+ 2.04)] and Wt = 1296.18 [1 – e–0.116(t+ 2.04)]2.846 for females, Lt = 46.36 [1 – e–0.133(t+ 1.76)] and Wt = 1381.86 [1 – e–0.133(t+ 1.76)]2.817 for males and Lt = 46.90 [1 – e–0.120(t+ 1.97)] and Wt = 1345.67 [1 – e–0.120(t+ 1.97)]2.831 for all individuals. The growth performance index (Ф´) value was calculated as 2.421 for all individuals. The condition factor ranged from 0.890 to 2.768 for females and from 0.899 to 2.767 for males. Conclusions. It is very important to investigate L. spadiceus, an invasive species, in order to prevent its harmful effects on fisheries and human health. As this study is the first study on the age and growth of L. spadiceus in the northeastern Mediterranean, it will significantly contribute to future ecosystem conservation and management strategies.
AtıfScopus6WoS5OpenAlex6İncele - BildiriYalnız künye2020Scopus SJRQ3Dynamic Features Spaces and Machine Learning: Open Problems and Synthetic Data Sets
Kaya, Sema Kayapinar; Navarro-Arribas, Guillermo; Torra, Vicenç; Huynh, V.; Entani, T.; Jeenanunta, C.; Inuiguchi, M.; Yenradee, P.
Dynamic feature spaces appear when different records or instances in databases are defined in terms of different features. This is in contrast with usual (static) feature spaces in standard databases, where the schema of the database is known and fixed. Then, all records in the database have the same set of variables, attributes or features. Dynamic feature mining algorithms are to extract knowledge from data on dynamic feature spaces. As an example, spam detection methods have been developed from a dynamic feature space perspective. Words are taken as features and new words appearing in new emails are, therefore, considered new features. In this case, the problem of spam detection is represented as a classification problem (a supervised machine learning problem). The relevance of dynamic feature spaces is increasing. The large amounts of data currently available or received by systems are not necessarily described using the same feature spaces. This is the case of distributed databases with data about customers, providers, etc. Industry 4.0, Internet of Things, and RFIDs are and will be a source of data in dynamic feature spaces. New sensors added in an industrial environment, new devices connected into a smart home, new types of analysis and new types of sensors in healthcare, all are examples of dynamic feature spaces. Machine learning algorithms are needed to deal with these type of scenarios. In this paper we motivate the interest for dynamic feature mining, we give some examples of scenarios where these techniques are needed, we review some of the existing solutions and its relationship with other areas of machine learning and data mining (e.g., incremental learning, concept drift, topic modeling), we discuss some open problems, and we discuss synthetic data generation for this type of problem.
AtıfScopus4WoS3OpenAlex3İncele - BildiriYalnız künye2020Classification of Hand-Drawn Basic Circuit Components Using Convolutional Neural Networks
Gunay, Mihriban; Koseoglu, Murat; Yildirim, Ozal
In this paper, the Convolutional Neural Network (CNN) architecture, which is one of the deep learning architectures, is used to classify the basic circuit components drawn by hand. During the training and testing stages of the model, a new dataset containing images of 863 circuit components manually drawn by different people is created. The data set contains images of four different classes of circuit components such as resistor, inductor, capacitor and voltage source. All images have been fixed to the same size and converted to grayscale to increase recognition performance and reduce process complexity. In the study, training for four classes is performed with CNN architecture. Based on the CNN architecture, four new CNN models are employed with different the number of layers. The training and validation results of these models are compared separately, the model with the highest training and validation performance is observed with four layer CNN model (CNN-4). This model obtained 84.41% accuracy rate at classification task.
AtıfScopus16WoS5OpenAlex17İncele - MakaleYalnız künye2020Scopus SJRQ1Study on model uncertainty of water source heat pump and impact on decision making
Zhang, Ying; Akkurt, Nevzat; Yuan, Jiaqi; Xiao, Ziwei; Wang, Qianjiang; Gang, Wenjie
Water source heat pump systems are widely used for cooling and heating due to high efficiency. The energy source can be surface water or underground water. Accurate modeling of water source heat pump systems is the basis for performance prediction, design and control optimization. However, various heat pump models are available to predict the system performance and results obtained can be very different under different models due to the model uncertainty. Without considering these uncertainties, the performance of water source heat pump systems would be overestimated or underestimated and the decision making would be affected. This paper attempts to quantify the model uncertainty of water source heat pump and its impact on the system performance. Thirteen commonly-used models are selected and validated using the manufacture data. By importing these models into the water source heat pump system, the impact of heat pump model uncertainty on the system performance is quantified. It shows that the model uncertainty can result in a deviation of up to 30% in the annual energy consumption. The energy saving potential of water source heat pump systems can vary from -18.43% to 14.78% compared with the chillers & boiler in the hot summer and cold winter area. The priority of water source heat pump systems is also controversial. The difference in the annual average coefficient of performance of the system can be up to 1.22. It demonstrates that the model uncertainty of water source heat pumps affects the system performance significantly and should be taken into account in building energy prediction and design optimization. The models considering the correction of part load ratio are recommended.
AtıfScopus40WoS34OpenAlex45İncele - MakaleYalnız künye2020Scopus SJRQ2Seismic vulnerability assessment of RC buildings according to the 2007 and 2018 Turkish seismic codes
Yön, Burak
Fragility curves are useful tools to estimate the damage probability of buildings owing to seismic actions. The purpose of this study is to investigate seismic vulnerability of reinforced concrete (RC) buildings, according to the 2007 and 2018 Turkish Seismic Codes, using fragility curves. For the numerical analyses, typical five-and seven-storey RC buildings were selected and incremental dynamic analyses (IDA) were performed. To complete the IDAs, eleven earthquake acceleration records multiplied by various scaling factors from 0.2g to 0.8g were used. To predict nonlinearity, a distributed hinge model that involves material and geometric nonlinearity of the structural members was used. Damages to confined concrete and reinforcement bar of structural members were obtained by considering the unit deformation demands of the 2007 Turkish Seismic Code (TSC-2007) and the 2018 Turkey Building Earthquake Code (TBEC-2018). Vulnerability evaluation of these buildings was performed using fragility curves based on the results of incremental dynamic analyses. Fragility curves were generated in terms of damage levels occurring in confined concrete and reinforcement bar of structural members with a lognormal distribution assumption. The fragility curves show that the probability of damage occurring is more according to TBEC-2018 than according to TSC-2007 for selected buildings.
AtıfScopus16WoS12OpenAlex7İncele - MakaleAçık Erişim2020Scopus SJRQ3Removal of tetracycline antibiotic by Lemna gibba L. from aqueous solutions
Topal, Murat; Öbek, Erdal; Uslu Şenel, Gülşad; Arslan Topal, E. Işıl
In this study, the efficiency of Lemna gibba L. on tetracycline (TC) removal from the solutions prepared at various initial TC concentrations (50, 100 and 300 µg/L) was investigated. The study was conducted in the reactors planted with Lemna gibba L. plants. Lemna gibba L. plants in the reactors were harvested at various hydraulic retention times. Then, the concentrations of TC were determined by using LC/-MS-MS. The maximum removal efficiencies for the TC50, TC100 and TC300 in the planted reactors were 99.8 ± 4.1; 99.9 ± 4.9 and 99 ± 4.9%, respectively. The harvesting times for Lemna gibba L. at TC50, TC100 and TC300 concentrations were determined to be 12, 8 and 12 hours, respectively. First-, second- and pseudo-first-order kinetics are determined in the planted reactors (with Lemna gibba L.). According to the study results, second-order kinetics were obtained at TC50, TC100, TC300 concentrations. As a result, the Lemna gibba L. plant can be used as an alternative treatment method to other advanced treatment methods and it can be done with a cheap method by adapting to existing treatment plants. Lemna gibba L. plants can be used to remove pollutants by applying them to polluted lakes and water bodies.
AtıfScopus12OpenAlex11İncele - MakaleYalnız künye2020Scopus SJRQ1Techno-economic analyses of multi-functional liquid air energy storage for power generation, oxygen production and heating
Wang, Chen; Akkurt, Nevzat; Zhang, Xiaosong; Luo, Yimo; She, Xiaohui
Liquid air energy storage (LAES) is increasingly popular for decarbonizing the power network. At off-peak time, ambient air after purification is liquefied and stored; at peak time, the liquid air is discharged to generate power. One of the key challenges for the LAES system is the lower economic benefit as peak electricity is usually the only source of income, leading to a longer payback period of ~15 years. To address this issue, this paper, for the first time, proposes a multifunctional LAES system, which not only generates peak electricity but also provides pure oxygen and heating. The proposed system is composed of an air separation unit (ASU), a nitrogen liquefaction unit (NLU) and a power generation unit (PGU). Thermodynamic and economic analyses are carried out on the proposed system. Compared with the baseline LAES system (NLU + PGU), the multifunctional LAES system has a lower round trip efficiency of ~0.39 due to the extra electricity consumption by the ASU. However, it shows a much better economic performance with additional benefits from pure oxygen and heating. In a project life-span of 30 years, the multifunctional LAES system (10 MW/80 MWh) has a short payback period of ~5.7 years. Furthermore, it has a savings-to-investment ratio of 3.12, which is ~153% higher than that of the baseline LAES system. Investigation on the system operation strategy suggests that the ASU should operate at full time. The proposed system provides a feasible way to improve the economic benefits of the LAES system, thus promoting its wide applications.
AtıfScopus82OpenAlex86İncele - MakaleYalnız künye2020Traces of late quaternary glaciations and paleoclimatic interpretation of Mount Akdağ (Alanya, 2451 m), Southwest Turkey
Bayrakdar, Cihan; Çılğın, Zeynel; Keserci, Ferhat
Mount Akdağ, located 25 km northeast of Alanya (2451 m above sea level a.s.l.), and largely made up of carbonates, is one of the mountains exposed to Late Quaternary glaciation in the Western Taurus Mountains. Although today, there are no modern glaciers, the traces of the Late Quaternary glaciers and rock glaciers are still fresh. In this study, geomorphological features related to the glaciations in Mount Akdağ, which were not previously reported in the literature, were first identified from satellite images, and then verified by field studies. The geomorphological development of Mount Akdağ during the Quaternary was explained by considering its climatic and karstic characteristics. For this purpose, spatial data obtained from field studies, unmanned aerial vehicles and meteorological stations were analysed using geographic information systems. Akdağ is directly open to humid air masses coming from the SW sector over the Mediterranean Sea, resulting in heavy orographic precipitation that encouraged the growth of glaciers. In addition, glacier reconstruction and pELA estimates have been made to contribute to the interpretation of glacial geomorphology. The pELA in Mount Akdağ was calculated with the AABR ratio of 1.69, and was found to be around 2030 m a.s.l. More than 15 cirques and a 6.5 km long glacial valley in Mount Akdağ indicate the presence of glaciers. Reconstruction of the paleoglaciers shows that the lowest altitude reached was 1410 m a.s.l. At their maximum extent glaciers covered an area of ~ 14 km2, with a volume of ~ 1 km3 and had an average thickness of 60 m with a maximum glacier thickness of ~ 200 m.
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