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  • Article
    Citation - WoS: 5
    Citation - Scopus: 6
    Parallel and Consecutive-k-out-of-n< Systems Under Stochastic Deterioration
    (Elsevier Science inc, 2014) Eryilmaz, Serkan
    In this paper, we study parallel and consecutive-k-out-of-n:F systems consisting of components which are subject to random deterioration with time. The random deterioration in resistance of a component is defined through a stochastic process. We obtain lifetime distribution of a parallel system via classical probabilistic techniques. The lifetime distribution of a consecutive-k-out-of-n:F system is derived using the lifetime distribution of parallel systems and the concept of maximal signature. We also study the optimal replacement time for a parallel system. We present illustrative computational results using MATHCAD. (C) 2013 Elsevier Inc. All rights reserved.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 6
    A Conceptual Design of Smart Management System for Flooding Disaster
    (Mdpi, 2021) Ibrahim, Thaer; Mishra, Alok
    Disasters pose a real threat to the lives and property of citizens; therefore, it is necessary to reduce their impact to the minimum possible. In order to achieve this goal, a framework for enhancing the current disaster management system was proposed, called the smart disaster management system. The smart aspect of this system is due to the application of the principles of information and communication technology, especially the Internet of Things. All participants and activities of the proposed system were clarified by preparing a conceptual design by using The Unified Modeling Language diagrams. This effort was made to overcome the lack of citizens' readiness towards the use of information and communication technology as well as increase their readiness towards disasters. This study aims to develop conceptual design that can facilitate in development of smart management system for flooding disaster. This will assist in the design process of the Internet of Things systems in this regard.
  • Article
    Citation - WoS: 20
    Citation - Scopus: 21
    Electrochemical Behaviour and Electrochemical Polymerization of Fluoro-Substituted Anilines
    (Wiley, 2002) Cihaner, A; Önal, AM
    The electrochemical behaviour of three fluoro-substituted aniline monomers, 2-fluoroaniline (2FAN), 3-fluoroaniline (3FAN) and 4-fluoroaniline (4FAN), was investigated in aqueous acidic and organic media by means of cyclic voltammetry (CV) studies. Constant potential electrolysis (CPE) of the monomers in acetonitrile-water mixture (1: 1 by volume) using NaClO4 as supporting electrolyte yielded soluble polymers. The mechanism of electrochemical polymerization was investigated using in situ electron spin resonance (ESR) and in situ UV-VIS spectroscopic techniques for one of the monomers (4FAN). Both CV and in situ LTV-VIS measurements indicated that the polymers obtained are in the emeraldine base form. In situ ESR studies indicated that electrochemical polymerization involves a radical-cation as an intermediate. Characterization of polymer products have been carried out using FTIR and NMR spectroscopic techniques, and thermal behaviour was studied using differential scanning calorimetry (DSC). It was found that conductivity can be imparted to assynthesized polyfluoroanilines via iodine doping. (C) 2002 Society of Chemical Industry.
  • Article
    Citation - WoS: 9
    Citation - Scopus: 9
    Urinalysis of Individuals With Renal Hyperfiltration Using Atr-Ftir Spectroscopy
    (Nature Portfolio, 2022) Kurultak, Ilhan; Sarigul, Neslihan; Kodal, Nil Su; Korkmaz, Filiz
    Abnormal increased glomerular filtration rate (GFR), otherwise known as renal hyperfiltration (RHf), is associated with an increased risk of chronic kidney disease and cardiovascular mortality. Although it is not considered as a disease alone in medicine today, early detection of RHf is essential to reducing risk in a timely manner. However, detecting RHf is a challenge since it does not have a practical biochemical marker that can be followed or quantified. In this study, we tested the ability of ATR-FTIR spectroscopy to distinguish 17 individuals with RHf (hyperfiltraters; RHf (+)), from 20 who have normal GFR (normofiltraters; RHf(-)), using urine samples. Spectra collected from hyperfiltraters were significantly different from the control group at positions 1621, 1390, 1346, 933 and 783/cm. Intensity changes at these positions could be followed directly from the absorbance spectra without the need for pre-processing. They were tentatively attributed to urea, citrate, creatinine, phosphate groups, and uric acid, respectively. Using principal component analysis (PCA), major peaks of the second derivative forms for the classification of two groups were determined. Peaks at 1540, 1492, 1390, 1200, 1000 and 840/cm were significantly different between the two groups. Statistical analysis showed that the spectra of normofiltraters are similar; however, those of hyperfiltraters show diversity at multiple positions that can be observed both from the absorbance spectra and the second derivative profiles. This observation implies that RHf can simultaneously affect the excretion of many substances, and that a spectroscopic analysis of urine can be used as a rapid and non-invasive pre-screening tool.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 4
    Growth and Optical Characterization of Sn0.6sb0.4< Layer Single Crystals for Optoelectronic Applications
    (Elsevier Sci Ltd, 2022) Bektas, T.; Terlemezoglu, M.; Surucu, O.; Isik, M.; Parlak, M.
    SnSe compound is an attractive semiconductor material due to its usage in photovoltaic applications. The sub-stitution of Sb in the SnSe compound presents a remarkable advantage especially in point of tuning optical characteristics. The present paper reports the structural and optical properties of Sn1-xSbxSe (x = 0.4) layered single crystals grown by the vertical Bridgman method. To the best of our knowledge, this work is the first investigation of the Sn0.6Sb0.4Se crystal grown with the vertical Bridgman technique. X-ray diffraction (XRD) pattern of the grown crystal indicated the well crystalline structure of the grown crystals. Lattice strain and interplanar spacing of the crystal structure were determined using the XRD pattern. Scanning electron micro-scope images allowed to the observation of the layer crystal structure. The layer crystalline structure shows 2D material properties and provides 2D applications. Optical properties were revealed by carrying out Raman, ellipsometry and transmission measurements. Raman modes, refractive index, extinction coefficient, and dielectric spectra, band gap energy of the crystal were presented throughout the paper. The obtained results indicated that Sn1-xSbxSe (x = 0.4) layer single crystals may be an alternative potential for photovoltaic and optoelectronic applications.
  • Article
    Citation - WoS: 24
    Citation - Scopus: 24
    Complete Dehydrogenation of Hydrazine Borane on Manganese Oxide Nanorod-Supported Ni@ir Core-Shell Nanoparticles
    (Amer Chemical Soc, 2020) Yurderi, Mehmet; Top, Tuba; Bulut, Ahmet; Kanberoglu, Gulsah Saydan; Kaya, Murat; Zahmakiran, Mehmet
    Hydrazine borane (HB; N2H4BH3) has been considered to be one of the most promising solid chemical hydrogen storage materials owing to its high hydrogen capacity and stability under ambient conditions. Despite that, the high purity of hydrogen production from the complete dehydrogenation of HB stands as a major problem that needs to be solved for the convenient use of HB in on-demand hydrogen production systems. In this study, we describe the development of a new catalytic material comprised of bimetallic Ni@Ir core-shell nanoparticles (NPs) supported on OMS-2-type manganese oxide octahedral molecular sieve nanorods (Ni@Ir/OMS-2), which can reproducibly be prepared by following a synthesis protocol including (i) the oleylamine-mediated preparation of colloidal Ni@Ir NPs and (ii) wet impregnation of these ex situ synthesized Ni@Ir NPs onto the OMS-2 surface. The characterization of Ni@Ir/OMS-2 has been done by using various spectroscopic and visualization techniques, and their results have revealed the formation of well-dispersed Ni@Ir core-shell NPs on the surface of OMS-2. The catalytic employment of Ni@Ir/OMS-2 in the dehydrogenation of HB showed that Ni-0.22@Ir-0.78/OMS-2 exhibited high dehydrogenation selectivity (>99%) at complete conversion with a turnover frequency (TOF) value of 2590 h(-1) at 323 K, which is the highest activity value among all reported catalysts for the complete dehydrogenation of HB. Furthermore, the Ni-0.22@Ir-0.78/OMS-2 catalyst enables facile recovery and high stability against agglomeration and leaching, which make it a reusable catalyst in the complete dehydrogenation of HB. The studies reported herein also include the collection of wealthy kinetic data to determine the activation parameters for Ni-0.22@Ir-0.78/OMS-2-catalyzed dehydrogenation of HB.
  • Article
    Citation - WoS: 13
    Citation - Scopus: 13
    Are Gender-Neutral Pronouns Really Neutral? Testing a Male Bias in the Grammatical Genderless Languages Turkish and Finnish
    (Sage Publications inc, 2023) Renstrom, Emma A.; Lindqvist, Anna; Akbas, Gulcin; Hekanaho, Laura; Senden, Marie Gustafsson
    Languages differ in how grammatically salient gender is. We explored if grammatically gender-neutral pronouns in Finnish and Turkish, two grammatically genderless languages, are gender neutral or male biased, thereby activating male, rather than female, exemplars. We also tested whether differences in national level gender equality influence the male bias. Results indicated a male bias in both languages, whereas national level gender equality had no influence. Implications for gender-fair language reforms in grammatically genderless languages are discussed.
  • Review
    Citation - WoS: 88
    Citation - Scopus: 95
    Vision 2023: Forecasting Turkey's Natural Gas Demand Between 2013 and 2030
    (Pergamon-elsevier Science Ltd, 2013) Melikoglu, Mehmet
    Natural gas is the primary source for electricity production in Turkey. However, Turkey does not have indigenous resources and imports more than 98.0% of the natural gas it consumes. In 2011, more than 20.0% of Turkey's annual trade deficit was due to imported natural gas, estimated at US$ 20.0 billion. Turkish government has very ambitious targets for the country's energy sector in the next decade according to the Vision 2023 agenda. Previously, we have estimated that Turkey's annual electricity demand would be 530,000 GWh at the year 2023. Considering current energy market dynamics it is almost evident that a substantial amount of this demand would be supplied from natural gas. However, meticulous analysis of the Vision 2023 goals clearly showed that the information about the natural gas sector is scarce. Most importantly there is no demand forecast for natural gas in the Vision 2023 agenda. Therefore, in this study the aim was to generate accurate forecasts for Turkey's natural gas demand between 2013 and 2030. For this purpose, two semi-empirical models based on econometrics, gross domestic product (GDP) at purchasing power parity (PPP) per capita, and demographics, population change, were developed. The logistic equation, which can be used for long term natural gas demand forecasting, and the linear equation, which can be used for medium term demand forecasting, fitted to the timeline series almost seamlessly. In addition, these two models provided reasonable fits according to the mean absolute percentage error, MAPE %, criteria. Turkey's natural gas demand at the year 2030 was calculated as 76.8 billion m(3) using the linear model and 83.8 billion m(3) based on the logistic model. Consequently, found to be in better agreement with the official Turkish petroleum pipeline corporation (BOTAS) forecast, 76.4 billion m(3), than results published in the literature. (C) 2013 Elsevier Ltd. All rights reserved.
  • Article
    Citation - WoS: 10
    Citation - Scopus: 13
    Is There an Informal Employment Wage Penalty in Egypt? Evidence From Quantile Regression on Panel Data
    (Physica-verlag Gmbh & Co, 2020) Tansel, Aysit; Keskin, Halil Ibrahim; Ozdemir, Zeynel Abidin
    This is the first study that uses panel data to assess the magnitude of the informal sector wage gap in Egypt. We consider the private sector male wage earners in Egypt and examine their wage distribution during 1998-2012 using the Egyptian Labor Market Panel Survey. We estimate Mincer wage equations both at the mean and at different quantiles of the wage distribution taking into account observable and unobservable characteristics with a fixed effect model. We also consider the possibility of nonlinearity in covariate effects and estimate a variant of matching models. We find a persistent informal wage penalty in the face of extensive sensitivity checks. It is smaller when unobserved heterogeneity is taken into account, and unlike many previous studies, there are very few differences across the conditional wage distribution. We also examine the informal wage penalty over time and in different subgroups according to age and education. The informal wage penalty has increased recently over time and is larger for the higher educated and the young.
  • Conference Object
    Citation - WoS: 16
    Citation - Scopus: 18
    Determinants of Entry in Turkish Manufacturing Industries
    (Springer, 2006) Gunalp, Burak; Cilasun, Seyit Mumin
    The entry of new firms into markets plays an important role in efficient resource allocation and evolution for long term economic growth. Employing dynamic panel data techniques, this paper investigates entry behavior in 66 four-digit Turkish manufacturing industries for the 1993-1999 period. The results of this paper suggest that potential entrants observe the market before the entry takes place; entry is, in general, a follow-up process; and incumbent firms seem to collude to prevent entry in Turkish manufacturing industries. In addition, the real interest rate appears to be a very important determinant of entry decision.