Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Uzun, Sevda(77)
- Merdan, Mehmet(73)
- Duran, Celal(54)
- Ozdes, Duygu(50)
- Baltaci, Cemalettin(45)
- Kaygusuz, Abdullah(45)
- Kulakaç, Nurşen(39)
- Ashyralyyev, Charyyar(38)
- Karsli, Orhan(37)
- Demir, Selim(36)
- Öztürk, Serkan(36)
- Dokuz, Abdurrahman(35)
- Turan, Ibrahim(35)
- Araz, Onur(33)
- Kandemir, Raif(31)
- Sipahi, Ferkan(30)
- Topal, Fevzi(30)
- Kurt, Kemal(28)
- Peker, Iskender(28)
- Arslan, Mehmet(27)
- Baltacı, Cemalettin(27)
- Maden, Nafiz(27)
- Ozturk, Samet(27)
- Aydin, Aydanur(26)
- Vural, Alaaddin(26)
- Bayrakdaroglu, Serdar(25)
- Kurnaz, Muammer(25)
- Reis, Hatice Catal(25)
- Akar, Zeynep(24)
- Aydin, Faruk(24)
- Gücer, Mehmet Ali(24)
- Topal, Meryem(24)
- Yolcu, Halil(24)
- Yücel, Cem(24)
- Anaç, Halil(23)
- Kankal, Murat(23)
- Ürkek, Bayram(23)
- Aliyazicioglu, Yuksel(22)
- Günen, Mehmet Akif(22)
- Tuncer, Metin(22)
Yayınlar
- MakaleYalnız künye2018Scopus SJRQ2Investigation of high temperature wear resistance of TiCrAlCN/TiAlN multilayer coatings over M2 steel
Sukuroglu, E.E.; Baran, O.; Totik, Y.; Efeoglu, I.
In this study, TiCrAlCN/TiAlN multilayer coatings were deposited on M2 high speed steel substrates by the Closed-Field Unbalanced Magnetron Sputtering system. The chemical composition, microstructure, morphology, mechanical and high temperature wear resistance properties of the coatings were characterized, analyzed and compared to the substrate. The high temperature wear tests were carried out under a load of 2 N at the lap (wear test distance) of 50 m and in dry sliding condition at Room Temperature (RT), 150, 300, 450, and 600 °C on atmospheric conditions. It has been found that the TiCrAlCN/TiAlN multilayer coatings have a higher wear resistance than the M2 substrate. The stable friction behavior and low friction tendency was determined at 600 °C. When the test temperature increased, the wear rates decreased. Narrow and smooth wear tracks and also the lowest wear rate were obtained at 600 °C.
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İncele - MakaleYalnız künye2018Scopus SJRQ1The effect of reiki on pain: A meta-analysis
Demir Doğan, Melike
Objective: Pain is one of the most common symptoms and may lead to important psychological, mental, and physiological problems in individuals. According to data by The Center for Reiki Research, Reiki is an effective approach to decrease the levels of pain, depression, and anxiety. Therefore, the aim of this meta-analysis was to investigate the effect of Reiki on pain level. Methods: Randomized controlled clinical trials in databases of Pubmed, ISI Web of Sciences, and Google Scholar were investigated. 4 randomized controlled studies involving 212 participants were included in the meta-analysis. Results: The result obtained after the final Reiki application was evaluated in VAS pain score. When Reiki (n = 104) group was compared with control group (n = 108), standardized mean difference was observed to be −0.927 (95% CI: −1.867 to 0.0124). Reiki was observed to cause a statistically significant decrease in VAS score. Conclusion: Consequently, this meta-analysis revealed that Reiki was an effective approach in relieving the pain.
AtıfScopus63WoS56OpenAlex93
İncele - BildiriYalnız künye2018A third order of accuracy difference scheme for Bitsadze-Samarskii type elliptic overdetermined multi-point problem
Ashyralyyev, Charyyar; Akyüz, Gulzlpa; Ashyralyev, A.; Sadybekov, M.; Lukashov, A.
In this study, a third order of accuracy difference scheme for Bitsadze-Samarskii type multi-point elliptic overdetermined problem is studied. For solution of constructed difference problem stability, almost coercive stability and coercive stability estimates are established. The theoretical statements for the solution of this difference problem are supported by numerical results in test example by using Matlab.
- MakaleAçık Erişim2018Scopus SJRQ2Experimental analysis for heat transfer of nanofluid with wire coil turbulators in a concentric tube heat exchanger
Akyürek, Eda Feyza; Geliş, Kadir; Şahin, Bayram; Manay, Eyüphan
Nanofluids are a novel class of heat transfer suspensions of metallic or nonmetallic nanopowders with a size of less than 100 nm in base fluids and they can increase heat transfer potential of the base fluids in various applications. In the last decade, nanofluids have become an intensive research topic because of their improved thermal properties and possible heat transfer applications. For comparison, an experiment using water as the working fluid in the heat exchanger without wire coils was also performed. Turbulent forced convection heat transfer and pressure drop characteristics of Al2O3-water nanofluids in a concentric tube heat exchanger with and without wire coil turbulators were experimentally investigated in this research. Experiments effected particle volume concentrations of 0.4–0.8 to 1.2–1.6 vol% in the Reynolds number range from 4000 to 20,000. Two turbulators with the pitches of 25 mm and 39 mm were used. The average Nusselt number increased with increasing the Reynolds number and particle concentrations. Moreover, the pressure drop of the Al2O3-water nanofluid showed nearly equal to that of pure water at the same Reynolds number range. As a result, nanofluids with lower particle concentrations did not show an important influence on pressure drop change. Nonetheless, when the wire coils used in the heat exchanger, it increased pressure drop as well as the heat transfer coefficient.
AtıfScopus121WoS110OpenAlex126İncele - BildiriYalnız künye2018Experimental Channel Measurement for Indoor Office Visible Light Communication
Yazgan, Ayhan; Simsek, Cemaleddin; Albayrak, Cenk; Tugcu, Emin; Turk, Kadir; Herencsar, N.
Channel measurement for visible light communication (VLC) is theoretically and experimentally performed in a real office platform. Six armatures composed of phosphor based white LED arrays are fed by designed analog LED drivers. Measurements are taken in a 6m x 7.8m office room which is formed as 10×13 matrix with 60 cm grid distance for both simulation and experiment studies. The link distance between LED arrays and optical receiver is kept minimum 2.5 meters for each measurement. Experimental results are generally in good agreement with simulation results, which are obtained using Barry's theoretical channel model.
AtıfScopus3OpenAlex4İncele - MakaleAçık Erişim2018The relationship between university students' music preferences and drug abuse tendencies and personality traits
Altun, Zühal Dinç; Bülbül, Kenan; Türkkan, Tuğba
The purpose of this study is to determine whether music preferences differ in terms of drug abuse tendencies and personality traits with regard to the type of music that music teacher candidates listen to. The research group of the study was comprised of 141 university students. Research data were collected using the Substance Use Tendency Scale, the Adjective-Based Personality Test (ABPT), and the Personal Information Form developed by the researchers. Pop music (93.6%) was determined to be the music type most listened to, and Heavy Metal music (21.3%) music the type least listened to. While the students were determining their music preferences, they indicated that the moods (99.3%) and the melody of the music (98.6%) were primarily important. The results of the analysis show that there are significant differences in music preferences based on the tendency for drug abuse and on personality traits. Findings have been discussed in the light of the relevant literature, and proposals have been made to professionals working in the fields of research, music therapy and music education.
AtıfScopus4OpenAlex6İncele - MakaleYalnız künye2018Scopus SJRQ2Shelf-life, physicochemical, and nutritional properties of wheat bread with optimized amount of dried chickpea sourdough and yeast by response surface methodology
Hendek Ertop, Muge; Coşkun, Yunus
The aim of this study was to optimize of the instant active dry yeast (A) and the dried chickpea sourdough (B) amount in bread formulation and to evaluate of usage possibilities of dried chickpea sourdough in bread production by examining some quality parameters.Response surface methodology was used to determine the effects of the variable factors (Aand B) on the product volume (V), acceptability value (AV) and pore factor (PF) of the bread. The usage rates were determined 0.63% for A and 10.21% for B.The bread produced according to optimized model (OB) was compared with control bread in terms of some quality parameters. The pore structures of bread samples and microtextural features obtained scanning electron microscopy during shelf life were examined by Image Analysis. Smaller and more homogeneous pore structures were obtained in the bread texture; antioxidant activity, mineral content, microbial shelf life were improved, and the volume and crust thickness of the bread increased by the usage of chickpea sourdough. Practical applications: Chickpea sourdough was dried in oven at low temperature short time condition.The protection of microbial vitality was ensure during the drying processes.The level of instant active dry yeast (A) and dried sourdough (B) were optimized with RSM. The usage rates were determined 0.63% for A and 10.21% for B.Optimized bread and control bread were compared in terms of various quality properties. The antioxidant activity, mineral content, microbial shelf life, and physicochemical properties were improved.
AtıfScopus20WoS16OpenAlex23İncele - MakaleAçık Erişim2018Obesity in adolescents and the risk factors
Eker, Hasan Hüseyin; Taşdemir, Mustafa; Mercan, Sümeyye; Mucaz, Meltem; Bektemur, Güven; Sahinoz, Saime; Ozkaya, Emin
Objectives: This study aims to investigate the frequency of obesity and to identify possible risk factors affecting obesity in adolescents. Materials and methods: This cross-sectional study included a total of 1,357 adolescents between March 2011 and May 2012 in Beyoglu district of Istanbul province of Turkey. The questionnaire including 38 questions which was developed based on the Youth Risk Behavior Survey, which is used by the Center for Disease Control and Prevention (CDC), was used for the data collection. The weight and height of the participants were measured and their body mass index (BMI) values were calculated. Results: Of all participants, 54.8% were females, 5% of them were underweight, 12.6% were overweight, and 2.6% were obese. Among the male participants, the BMI values were higher (21.06±3.32 kg/m2) than females (20.26±2.88 kg/m2) (p<0.0001). The obesity ratio was higher in males (p<0.0001) and in children of highly educated parents (p<0.05). Of the participants, 23.5% were physically active. Physical activity level was higher in males, compared to females (p<0.0001). The rate of breakfast habit was higher in males than females (p=0.002). Healthy diets and losing weight in a healthy way were more commonly accepted by the students in the public schools, compared to those in private schools (p<0.0001). Conclusion: Obesity is an important public health problem and proper eating habits and regular physical activity should be encouraged. High-income families should also encourage their children to become more aware of the importance of physical activity. The right time for this is childhood and adolescence, in which permanent habits can be easily acquired.
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İncele - MakaleYalnız künye2018Scopus SJRQ2Increasing adherence to mine plan through data integration and process change
Kahraman, Muhammet Mustafa; Dessureault, Sean
This paper focuses on the development of a decision support element to control real-time adherence to mine plan within a control room environment. This system, known as a mine planning screen (MPL), integrates mine planning and production processes. The key inputs are production data tracked by the fleet management system and mine plans entered by mine planners into spreadsheets. The data are integrated with the use of database query languages and MPL charts are displayed in a web environment. The MPL screen displays two types of information: real-time adherence to plan by pit and historical adherence by crews. The objective of the screen is to increase adherence to the overall plan, a key part of a larger real-time blending initiative. This research discusses the technical development of the new tool, its deployment and peer pressure technique for user motivation.
AtıfScopus2WoS2OpenAlex4İncele - BildiriYalnız künye2018Performance of Visible Light Communication with Colour Shift Keying Modulation and Polar Code
Simsek, Cemaleddin; Tugcu, Emin; Albayrak, Cenk; Yazgan, Ayhan; Turk, Kadir; Herencsar, N.
Visible light communication (VLC) is an emerging technology to fulfill both illumination and communication purposes considered as either an alternative or a support system for some of scenarios carried by RF communication systems. Colour shift keying (CSK) is the modulation given in IEEE 802.15.7 VLC standard which proposes Reed-Solomon as error correction code. Polar code is the first theoretically proven capacity achieving error correction code with low encoding and decoding complexities. Performance of Polar code with belief propagation decoder has not been studied under VLC CSK scheme. In this study we investigate performance of Polar code with belief propagation decoder under VLC CSK scheme and compare it with performance of Reed-Solomon code. Result show that Polar code with belief propagation decoder outperforms Reed-Solomon code by at least 1.5dB.
AtıfScopus4WoS4OpenAlex4İncele - BildiriYalnız künye2018Fast and accurate classifier-based brain-computer interface system using single channel EEG data
Maleki, Masoud; Manshouri, Negin; Kayikcioglu, Temel
In brain-computer interface system (BCIs), direct communication between humans and computers is performed by analyzing neural signals and transforming them into digital signals. In the continuation of our previous works, in this paper, we advanced the proposed BCI system that was based on the gaze on rotating vanes. The speed of communication and convenience of the user are very important factors in BCI systems. Therefore, in this paper, for the convenience of the user, a single EEG channel was used. Also, for to increase the speed of the system, we tried to the classification of 0.5 sec epochs with a partial least squares regression (PLSR) as a fast classifier. In addition, we computed the information transfer rate (ITR) that has proved our proposed BCI system is fast and accurate. This system could be used in real-time implementations due to having high classification rate, speed and convenience of the user.
AtıfScopus6OpenAlex5İncele - MakaleAçık Erişim2018Energy concept understanding of high school students: A cross-grade study
Takaoğlu, Zeynep Başkan
Energy is a difficult concept to be understood by students of all levels. Thus, the aim of the study is to determine how high school students at different levels perceive the energy and related concepts. In line with this purpose, 173 students in total of which 57 ones of the 9th grade, 94 ones of the 10th grade and 22 ones of the 11th grade participated in the study in which developmental research method of descriptive research design has been conducted. Four open-ended questions about energy and related concepts have been asked to the students in the study. As a result of the study, it is concluded that the students use energy instead of work, power, repulsion and pulling concepts and they consider energy as a feature specific to living creatures and moving situations. The potential and kinetic energy types are most expressed ones. The students frequently give examples from renewable and non-renewable energy types and they classify them accordingly. It is also concluded that they don’t have enough information about conservation of energy. It is thought that this misconception among the students emerges because energy and related concepts are taught them disconnected in different lessons of different disciplines and they do not understand preconceptions about energy and related notions. It is considered that the concept networks, concept maps, and conceptual change texts will help to relate energy concepts in students' minds.
AtıfScopus10OpenAlex14İncele - Kitap BölümüYalnız künye2018Reputation management as a strategic practice of public relations in the frame of Turkey
Güllüpunar, Hasan
- MakaleAçık Erişim2018Scopus SJRQ3Bounds for radii of starlikeness and convexity of some special functions
Aktaş, Ibrahim; Baricz, Árpád; Orhan, Halit
In this paper we consider some normalized Bessel, Struve, and Lommel functions of the first kind and, by using the Euler-Rayleigh inequalities for the first positive zeros of a combination of special functions, we obtain tight lower and upper bounds for the radii of starlikeness of these functions. By considering two different normalizations of Bessel and Struve functions we give some inequalities for the radii of convexity of the same functions. On the other hand, we show that the radii of univalence of some normalized Struve and Lommel functions are exactly the radii of starlikeness of the same functions. In addition, by using some ideas of Ismail and Muldoon we present some new lower and upper bounds for the zeros of derivatives of some normalized Struve and Lommel functions. The Laguerre-Pólya class of real entire functions plays an important role in our study.
AtıfScopus37WoS36TR Dizin7İncele - MakaleYalnız künye2018Scopus SJRQ2A novel OTA-based circuit model corroborated by an experimental semiconductor memristor
Gul, Fatih; Babacan, Yunus
A semiconductor memristor device based on a 300-nm ZnO thin film was fabricated by direct-current reactive sputter. The memristive behavior of this device was confirmed by time dependent current–voltage (I-V-t) measurements, and the distinctive pinched hysteresis I-V loops of the memristor were observed. Structural analysis of the ZnO memristor was carried out using both X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). After physical implementation of the memristor, an operational transconductance amplifier (OTA) based memristor circuit was designed to emulate the ZnO-based semiconductor memristor for use in memristor-based circuit applications. All simulations were in good agreement with experimental results. In addition, a comparison of the proposed circuit with other memristor emulators was presented.
AtıfScopus29WoS27OpenAlex29İncele - MakaleYalnız künye2018Scopus SJRQ1Investigation of radiation absorption coefficients of lead-zinc mine waste rock mixed heavy concrete at 662–1460 keV energy range
Çullu, Mustafa; Bakırhan, Emir
The objective of this study is to observe the radiation shielding efficiency of concrete produced by using the lead wastes that are stored in lead-zinc mines processing of which is not financially viable in the mines they are extracted from that have negative effects on the environment. Within this scope, concretes were produced to be used as radiation shield concretes. The samples were prepared by altering the amounts of heavy aggregates such as lead–zinc mine waste, Magnetite, Limonite, and Barite at 25%, 50%, and 75% ratios, and concrete samples were prepared in C16/20, C25/30, and C35/45 concrete strength grades to determine the effects of these grades on radiation absorption properties. In order to determine the radiation absorption coefficients, absorption coefficients at 662 keV, 1173 keV, 1332 keV, and 1460 keV energy levels from Cs-137, Co-60 and K-40 sources were determined by concrete slabs with dimensions of 20 × 20 × 5 cm.
AtıfScopus35WoS33OpenAlex32İncele - MakaleAçık Erişim2018Scopus SJRQ3Evaluation of enamel surface morphology and microhardness after the application of different protective agents
Simsek, Huseyin; Derelioglu, Sera; Buyuk, Suleyman Kutalmış; Sukuroglu, Ebru Emine
The aim of this in vitro study was to compare the effect of different protective agents on the surface microhardness and morphology on enamel eroded by a cola drink. Sixty sound anterior teeth were randomly divided into five groups. The baseline surface microhardness of the enamel was measured. For demineralization procedures, all teeth were immersed in cola for 8 minutes and surface microhardness was remeasured. The five groups for remineralization procedures were defined as: Group 1: Artificial saliva, Group 2: 1.23% Acidulated Phosphate Fluoride gel (APF), Group 3: 5% NaF varnish, Group 4: Casein Phosphopeptide-Amorphous Calcium Phosphate (CPP-ACP), and Group 5: Probiotic yogurt. After each experimental procedure, a third microhardness measurement was repeated. Surface morphological changes were observed using SEM. All data were recorded for each group and statistically analyzed using two-way analysis of variance and one-way repeated-measures analysis of variance. All tests were performed at a significance level of p < 0.05. No significant differences for baseline microhardness values were found (P> 0.05). The mean surface microhardness in all groups decreased significantly after immersion in cola (P< 0.05). After remineralization, NaF varnish and APF gel significantly increased the surface microhardness values. There were no significant increases in the surface microhardness values of artificial saliva, CPP-ACP and probiotic yogurt. This study concludes that NaF varnish is more effective in re-hardening of eroded enamel.
AtıfScopus2WoS2OpenAlex5İncele - MakaleYalnız künye2018Scopus SJRQ1Competitive positioning of winter tourism destinations: A comparative analysis of demand and supply sides perspectives–Cases from Turkey
Evren, Savaş; Kozak, Nazmi
This study was conducted to determine the competitive positions of five winter tourism destinations in Turkey. The explanatory sequential mixed method was used in order to compare the views of both the supply and demand sides. A questionnaire was first applied to current and potential visitors of the related destinations (n = 417), both in the field and online, followed by semi-structured interviews conducted with destination stakeholders (n = 12). It was observed that visitor perceptions positioned Uludağ with its tourism superstructure means and entertainment opportunities, Kartalkaya with its tourism superstructure quality and service quality, Erciyes, with its reasonable pricing policy and uncrowded slopes/lifts, Palandöken with its adequate number of lifts and snow quality, and Kartepe, with its beautiful scenery and accessibility. The assessments of the destination stakeholders demonstrated that strategies for strengthening the current position was not accepted at every destination and that only some destination stakeholders were inclined toward repositioning.
AtıfScopus42WoS37OpenAlex55İncele - BildiriAçık Erişim2018Finite difference approximations of first order derivatives of complex-valued functions
Ashyralyyev, Charyyar; Öztürk, Beyza; Ashyralyev, A.; Sadybekov, M.; Lukashov, A.
In this study, we generalize the well-known finite difference method to compute derivatives of a real-valued function to approximate complex derivatives wz and wz for complex-valued function w. Exploring different combinations of terms, we derive several approximations to compute the first order derivatives of complex-valued function. The first, second, third and fourth order of accuracy finite differences to calculate derivatives are studied. Error analysis in test examples are carried out by using Matlab program.
AtıfWoS1OpenAlex1İncele - MakaleYalnız künye2018Scopus SJRQ3An Extended Approach of Particle Swarm Optimization for Shoreline Extraction from RASAT Imagery
Catal Reis, Hatice; Bayram, Bülent; Bozkurt, Salih; Ince, Abdulkadir; Demir, Nusret; Seker, Dursun Zafer
This study presents an extended shoreline detection approach from pansharpened images of Turkish RASAT satellite which covers red, green and blue bands of the optical spectrum with 15 m ground resolution and panchromatic band with 7.5 m spatial resolution. The Lake Ercek of Turkey has been selected as the study area, which is a tectonic lake and home to a variety of water birds. The satellite images of the lake taken in 2013 and 2014 were considered for analysis. The proposed shoreline extraction system consists of a sequence of image processing steps in which simple linear clustering (SLIC) and particle swarm optimization (PSO) are the main components. SLIC was used to create superpixels that form basis for object-based image analysis while PSO was employed for classifying objects into corresponding classes. The resulting images still contained unwanted artefacts; therefore, a post-processing step was performed to improve the accuracy of segmentation by applying thresholding, morphological processing, and manual editing for noise removal. The proposed framework was applied on two temporal RASAT images to test the variations of defined parameter settings. The success of the proposed system was to obtain shorelines with satisfying accuracy without using NIR band. Finally, the extracted shorelines were vectorised and compared with manually digitized shorelines from pansharpened satellite images for accuracy assessment.
AtıfScopus3WoS2OpenAlex2İncele