Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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Now showing 1 - 10 of 22
  • Article
    Citation - WoS: 16
    Citation - Scopus: 19
    Comparative Analysis of Estimation of Slope-Length Gradient (ls) Factor for Entire Afghanistan
    (Taylor & Francis, 2023) Ansari, Ahmad; Tayfur, Gökmen
    Slope length gradient (LS) is one of the crucial factors in the Universal Soil Loss Equations (USLE, RUSLE). This study aimed at estimating the slope-length and slope-steepness (LS) factor for the entire watersheds of Afghanistan by using three different methods, namely; (1) LS-TOOLMFD (Method 1); (2) The Method of Equations (Method 2); and (3) The approach of Moore and Burch (Method 3). The first method uses the digital elevation model (DEM) in the ASCII format, and the other two methods use the DEM in the spatial domain. The results show that the LS-factor of the study area ranges from 0.01 to 44.31, with a mean of 5.24 and standard deviation of 6.95, according to Method 1; 0.03 to 163.49, with a mean of 9.6 and standard deviation of 13.58, according to Method 2; and 0 to 3985, with a mean of 7.16 and standard deviation of 29.7, according to Method 3. The study reveals that Methods 1 and 2 are more appropriate than Method 3 because Method 3 yields high LS-factor values close to or at streamlines located near mountainous regions. The highest LS values are found to be in the northeast, north, and central regions of Afghanistan, which is consistent with the high mountains and deep valley geomorphology, indicating that these regions are particularly vulnerable to soil erosion by rainfall-runoff processes. The sediment delivery ratio (SDR) for the Upper-Helmand River Basin (Upper-HRB) is also estimated by the RUSLE, employing the LS factors produced by the three methods. The results revealed that the average annual soil loss is found to be, respectively, 9.3, 18.2, and 11.1 (ton/ha/year) by using the three methods, corresponding to SDR of 23.5%, 12.1%, and 19.9%.
  • Article
    Citation - WoS: 7
    Citation - Scopus: 6
    An Intervention Framework for Developing Interactive Video Lectures Based on Video Clickstream Behavior: a Quasi-Experimental Evaluation
    (Taylor & Francis, 2022) Yürüm, Ozan Raşit; Yıldırım, Soner; Taşkaya Temizel, Tuğba
    The purpose of this study is to develop an intervention framework based on video clickstream interactions for delivering superior user experience for video lectures. Apart from existing studies on data-driven interventions, this study focuses on video clickstream interactions to identify timely interventions for creating interactive video lectures. First, a framework was developed through an exploratory experiment, in which 29 students’ clickstream behaviors were tracked on an online platform and then individual interviews were held with 17 of the students and a subject-matter expert. The framework shows how click types are transformed into interactive elements with five question types (where, why, which, how, what). It includes click types, click reasons, interventions, actions, and interactive elements. Then, a quasi-experimental study was performed with 18 students to investigate the effect of the proposed framework on the students’ satisfaction and engagement. The results showed that students’ satisfaction significantly increased for interactive videos created using the proposed framework when motivation was controlled. In addition, students’ frequency to go back to important points decreased significantly in interactive videos, whilst students’ frequency to skip unimportant points increased significantly in interactive videos. In conclusion, the proposed framework can be used to transform linear videos to interactive videos.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Anastelosis of Greco-Roman Temple Remains in Western Anatolia: Principlis, Implementations and Assessment
    (Taylor & Francis, 2020) Toköz, Özge Deniz; İpekoğlu, Başak
    Anastelosis, which is defined as the reassembly of a structure by bringing together its existing original fragments, is a technique of conservation and presentation in archaeological sites. The aim of this study is to contribute to the conservation and presentation of the structures and to determine the basic principles to be considered during the implementation by analysing and evaluating the anastelosis implementation at temple structures in Western Anatolia, Turkey. The authors examined on-site evidence, archival and literature review. Analysis criteria were determined as emphasis of the structure within site scale and in original state, structural and visual integrity of the monument, authenticity, reliability, distinguishability, visual and material compatibility, reversibility and re-treatability. As a result, it was pointed out that the principles of reversibility/re-treatability and distinguishability should be managed while providing reliability, compatibility/structural and visual integrity in line with the preservation of authenticity.
  • Article
    Citation - WoS: 15
    Citation - Scopus: 16
    The Usability of Juniperus Virginiana L. as a Biomonitor of Heavy Metal Pollution in Bishkek City, Kyrgyzstan
    (Taylor & Francis, 2015) Kurmanbekova, Gülbübü; Severoğlu, Zeki; Özyiğit, İbrahim İlker; Doğan, İlhan; Demir, Göksel; Yalçın, İbrahim Ertuğrul; Kaşoğlu, Gülten
    Uncontrolled and unplanned urbanization and industrialization due to increase of population and rapid industrial development have created severe environmental problems in Kyrgyzstan during the last few decades. In this study, Juniperus virginiana, a dioecious species, was employed in order to make assessment of the heavy metal pollution rate in the area and of the heavy metal pollution impact on the mineral nutrient status of the plant. For this study, leaf (washed and unwashed) and bark samples of J. virginiana, and its co-located soil samples were collected from eight different stations, all in the capital of Kyrgyzstan, Bishkek, in 2012 vegetation period. The standard procedures were used and the determinations of heavy metal and nutrient element contents (Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Pb and Zn) in all samples were done using inductively coupled plasma-optical emission spectroscopy. According to our measurements, J. virginiana was found to be capable of accumulating a considerable amount of metals and the mineral nutrient uptake pattern was altered because of metal deposition in the plant, which showed a contamination risk in the area.
  • Article
    Citation - WoS: 3
    Citation - Scopus: 4
    Environmental Assessment of Transparent Conductive Oxide-Free Efficient Flexible Organo-Lead Halide Perovskite Solar Cell
    (Taylor & Francis, 2020) Sarıaltın, Hüseyin; Geyer, Roland; Zafer, Ceylan
    Perovskite solar cells (PSCs), one of the third-generation photovoltaic (PV) technologies, have recently become a very popular topic in photovoltaic research. This technology, which is a candidate for commercialization in the future, needs to be evaluated from an environmental point of view. The amount of electricity consumption is the most important factor that directly determines the environmental impact values of photovoltaic cell manufacturing. Transparent conductive oxide (TCO) coated glass is one of the major contributors to electricity consumption in PSC architecture. It is therefore useful to investigate the environmental profile of TCO coated glass-free PSC architecture with conventional PVs. One of the solutions to this issue is manufacturing PSC on a flexible substrate. Flexible PVs are considered to be one of the most promising candidates for mass production with its advantages of low-temperature manufacturing, higher efficiency with a lower weight, portability, and compatibility with a roll to roll fabrication. In this work, we show that the environmental impacts of a representative PSCs with a flexible substrate. While the energy payback time (EPBT) of the flexible PSC is already competitive with commercial PVs, the device must reach a 25-year cell lifetime for its global warming potential (GWP) to reach a reasonable range.
  • Article
    Citation - WoS: 13
    Citation - Scopus: 14
    Landau, Ginzburg, Devonshire and Others
    (Taylor & Francis, 2020) Levanyuk, Arkady P.; Mısırlıoğlu, İbrahim Burç; Barış Okatan, Mahmut
    Macroscopic modeling of ferroelectric properties refers usually to Landau-Ginzburg-Devonshire theory. This paper questions the meaningfulness of this term, discussing contributions of the three authors in the title to what is supposed to be a theory. The limitations of every contribution are analysed. In the main text and, to more extent in the Supplementary Material, the Landau theory is presented from an unusual perspective starting from simple mechanical models of spontaneous symmetry breaking and finishing by the Ising model. The aim of the presentation is to emphasize along with the qualitative breakthroughs the approximate character of macroscopic modeling associated with the above three authors. © 2020 Taylor & Francis Group, LLC.
  • Book Part
    Water Sorption of Polyvinyl Chloride-Luffa Cylindrica Composites
    (Taylor & Francis, 2014) Demir, Hasan; Balköse, Devrim
    Natural Luffa Cylindrica fibers were modified with 0.1M sodium hydroxide (NaOH) for removing lignin and hemicellulose. Natural and modified Luffa fibers were characterized by using IR spectroscopy. Composites were produced with PVC plastisol and natural Luffa fiber. Natural Luffa fiber is a highly hydrophilic substance. This feature increased the water sorption capacity of the composites. Flexible PVC-luffa cylindrica composites had higher liquid water sorption capacity (0.3-0.6%) compared to that of flexible PVC (0.1%). There was no volume change of composites due to liquid water sorption.
  • Book Part
    Citation - Scopus: 4
    'the Hollow Victory' of Modern Architecture and the Quest for the Vernacular: J. M. Richards and 'the Functional Tradition'
    (Taylor & Francis, 2010) Erten, Erdem
    Introduction Modernism and anonymity have remained largely irreconcilable, especially in the fi eld of architecture. As the omnipotent symbol of creativity and artistic power, the personality of the nineteenth-century Romantic artist defi ned the transgressive nature of his early twentieth-century avant-garde successor, while nurturing the emergence of the celebrity architect. Valuing authorship above anonymity, the cult(ure) of avantgardism has invested the modern artist with the power to see beyond culture and tradition to generate cultural transformation. It is peculiar, then, to see that one of the chief editors of the leading modern architecture journals of Britain, J. M. Richards, wrote extensively on the idea of anonymity and the value of vernacular architectures.
  • Article
    Citation - WoS: 17
    Citation - Scopus: 18
    Electric Field Controlled Heat Transfer Through Silicon and Nano-Confined Water
    (Taylor & Francis, 2019) Yenigün, Onur; Barışık, Murat
    Nanoscale heat transfer between two parallel silicon slabs filled with deionized water was studied under varying electric field in heat transfer direction. Two oppositely charged electrodes were embedded into the silicon walls to create a uniform electric field perpendicular to the surface, similar to electrowetting-on-dielectric technologies. Through the electrostatic interactions, (i) surface charge altered the silicon/water interface energy and (ii) electric field created orientation polarization of water by aligning dipoles to the direction of the electric field. We found that the first mechanism can manipulate the interface thermal resistance and the later can change the thermal conductivity of water. By increasing electric field, Kapitza length substantially decreased to 1/5 of its original value due to enhanced water layering, but also the water thermal conductivity lessened slightly since water dynamics were restricted; in this range of electric field, heat transfer was doubled. With a further increase of the electric field, electro-freezing (EF) developed as the aligned water dipoles formed a crystalline structure. During EF (0.53 V/nm), water thermal conductivity increased to 1.5 times of its thermodynamic value while Kapitza did not change; but once the EF is formed, both Kapitza and conductivity remained constant with increasing electric field. Overall, the heat transfer rate increased 2.25 times at 0.53 V/nm after which it remains constant with further increase of the electric field.
  • Article
    Two dimensional bed deformation model in turbulent streams
    (Taylor & Francis, 2019) Gharehbaghi, Amin; Kaya, Birol; Tayfur, Gökmen
    A coupled model is developed to simulate two dimensional water surface profile, suspended sediment load and bed deformation in unsteady open channels. The hydrodynamical component employs the two dimensional shallow water equations to obtain the hydraulic variables. These, in turn, are used in the morphdynamical component to determine the bed deformation. For the turbulence variables; two turbulence models are supervened to the governing equations. Triangular meshes were developed to discretize the domain of open channel. In order to discretize the governing equations, the explicit finite volume method is used by the total variation diminishing (TVD) schemes. The performance of the developed model is compared to that of the Flow3D software. The comparison results are in good agreement.