WoS İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/394

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Now showing 1 - 10 of 15
  • Article
    Integrated Quantitative Modelling for the Dimension Stone Quality Evaluation: Implications for Sustainable Resource Management
    (Springer Heidelberg, 2025-09-30) Koken, Ekin; Strzalkowski, Pawel; Strzałkowski, Paweł
    The growing demand for dimensional stones in construction and monument conservation requires fast, repeatable and scientifically valid quality assessment procedures. The present study, in this context, established a solid foundation for quantifying the quality of dimension stones by adopting two quantitative methods: the Suitability Index (SI) and Dimension Stone Field Performance Coefficient (DSFPC). Both methods were coded in the MATLAB environment and implemented for 20 different rock types used in various dimension stone applications in Turkey. Evaluations based on the above-mentioned methods demonstrate that the DSFPC provides a more conservative assessment than the SI method. Additionally, engineering interpretations derived from the SI and DSFPC approaches are compared with recently published classification systems developed for the dimension stone industry. Focusing on this comparison, it is concluded that the adopted methods offer a more holistic evaluation framework compared to the approaches based solely on a single input parameter, such as effective porosity (ne), uniaxial compressive strength (UCS), or B & ouml;hme abrasion value (BAV) of rocks. Furthermore, it is concluded that the adopted methods complement each other by yielding supportive outcomes. The coded methods can be adapted to other lithological series and integrated with spatial information systems to support decision-making in mining and construction sectors. From this point of view, the present study may be considered a case study supporting holistic approaches to sustainable resource management in the dimension stone industry.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 4
    Towards Global Sustainable Development: The Role of Financial Innovation and Technological Advancements
    (Sage Publications Ltd, 2024-08-10) Dogan, Eyup; Chishti, Muhammad Zubair; Zaman, Umer; Binsaeed, Rima H.
    The importance of metaverse and blockchain technologies in today's global landscape cannot be overstated. These innovative technologies offer transformative potential for various sectors, including economics, by enhancing connectivity, security and transparency. The present study leverages these technologies to investigate their dynamic impacts, in conjunction with geopolitical risk, on global economic cycles to navigate the challenges of an interconnected world. To ensure the reliability of our findings, this study employs two proxies to gauge economic cycles: global green economic growth and global environmental sustainability. By utilizing daily data, this study reveals several noteworthy findings. First, the quantile-var-based network analysis demonstrates a robust directional connection among the variables in our model. Second, the wavelet quantile correlation technique uncovers the significant role of metaverse technology in influencing economic cycles by promoting global green economic growth and global environmental sustainability across all time horizons (short, medium and long term). Third, economic cycles exhibit a negative association with financial innovation and a positive connection with geopolitical risk across all timeframes. Fourth, the continuous wavelet transform causality test identifies a substantial causal relationship running from metaverse technology, financial innovation and geopolitical risk to economic cycles. Based on our empirical results, this study recommends that the global economy should continue investing in metaverse and blockchain technologies to address economic cycles in the future.
  • Article
    Citation - WoS: 14
    Citation - Scopus: 15
    Preparation of Antibacterial Electrospun Poly(D, L-Lactide-co-Glycolide)/Gelatin Blend Membranes Containing Hypericum Capitatum Var. Capitatum
    (Taylor & Francis As, 2020-05-18) Aksit, Nazende Nur; Gurdap, Seda; Isoglu, Sevil Dincer; Isoglu, Ismail Alper
    In this study, we fabricated poly(D, L-lactide-co-glycolide)/gelatin (PLGA/gelatin) membranes containing different amounts of Hypericum capitatum var. capitatum (HCC) extract (1, 5, 7.5, 10 wt%) by electrospinning technique. We investigated chemical, morphological, physical, and mechanical properties as well as in vitro degradation behavior of the electrospun membranes. We also evaluated the antibacterial activity of the electrospun membranes against Escherichia coli and Staphylococcus aureus. Viability, adhesion, and attachment of human fibroblast cells on the electrospun membranes on pre-set days were evaluated by the colorimetric CellTiter 96(R) AQueous One Solution Cell Proliferation Assay (MTS assay), scanning electron microscopy (SEM), and 4',6-Diamidino-2-Phenylindole (DAPI) staining.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 3
    Optimization of the Recycling Process for Aligned Short Carbon Fiber TuFF Composites
    (MDPI, 2025-04-01) Balaga, Uday Kiran; Gunes, Aydin; Ozdemir, Tekin; Blackwell, Chris; Davis, Mark; Sauerbrunn, Steven; Heider, Dirk
    Recycling of carbon fibers enables a sustainable feedstock for industrial applications of high-performance composite materials. This allows light weighting with recycled carbon fibers due to their superior mechanical properties while reducing the high embodied energy and cost of virgin carbon fiber composites. This study optimizes a pyrolysis cycle for fiber recovery of an aerospace-grade thermoset prepreg and a cleaning (oxidation) step to minimize fiber degradation and left-over resin residue, enabling dispersion and alignment of the recycled, discontinuous fibers in the Tailorable Universal Feedstock for Forming alignment process. The study balances the influence of the optimized thermal cycle (pyrolysis + oxidation step) on recycled carbon fiber strength retention with the ability to disperse at the filament level to create aligned, recycled carbon fiber composite samples with high fiber volume fraction. The optimized thermal cycle for efficient fiber recovery applied a pyrolysis step at 500 degrees C for 4 h in an inert gas environment and an additional oxidation step at the same temperature for 100 min. This resulted in similar to 20% strength degradation of the fiber compared to the virgin fiber. The processed recycled composite achieved 44% fiber volume fraction with full modulus translation (similar to 128 GPa) compared to the virgin continuous composite with strength translation (similar to 870 MPa), reaching similar to 50%.
  • Editorial
    Mobile Sensor Networks: Theory, Control, Communication, and Computation Issues
    (Hindawi Publishing Corporation, 2013-10-01) Gungor, V. Cagri; Gulez, Kayhan; Kawabata, Kuniaki; Tas, Nazif Cihan; Tuna, Gurkan
  • Article
    Citation - WoS: 3
    Citation - Scopus: 3
    Investigation of Distributed Series Reactors in Power System Applications and Its Economic Implementation
    (Wiley, 2016-08-18) Onen, Ahmet
    The transmission system expansion planning process requires lots of calculations looking many years into the future, and the results are based on assumed load growth. If the load growth assumed in the planning process is not correct and unexpected load growth occurs for some load points, the transmission system could face serious congestion and even overloading problems. In this paper, transmission line impedance adjustment techniques using distributed series reactance (DSR) is considered. The DSRs can be used to control power flow and alleviate overloading problems. A new term, DSR congestion relief factor, is introduced. The DSR congestion relief factor measures the increase of transmission line capacity with the application of DSRs. Parametric studies run on the IEEE 39-bus system are presented. These studies investigate the economic benefits of DSRs and the use of DSRs for single contingencies and compare DSRs with existing technologies for expanding the transmission system.
  • Article
    Citation - WoS: 7
    Citation - Scopus: 7
    Intersectional Power Dynamics and Extended Households: Elderly and Widowed Women's International Migration from Armenia
    (Routledge Journals, Taylor & Francis Ltd, 2018-11-17) Lloyd, Fatma Armagan Teke; Teke Lloyd, Fatma Armagan
    Drawing upon interviews and fieldwork conducted in Armenia and Turkey with 25 Armenian migrant women and their non-accompanying family members, the present article examines how gendered norms intersecting with age, marital and motherhood statuses have structured the migration decision-making process as it occurs at the household level. These migrant women were mostly elderly, widowed and from extended households, where male income support to the family was either insufficient or wholly absent for a variety of reasons. Building on the Household Survival Strategies (HSS) approach, this article examines the dynamism and complex kinship norms in extended-households and how these have led some women to assume the role of migrant labourers in a patriarchal context that would ordinarily deny them mobility. While empirically this study sheds light on women's migration from an understudied geography, it also deepens our understanding of the interplay between patriarchy, intersectionality and women's agency outside of the traditional nuclear household.
  • Article
    Citation - WoS: 29
    Citation - Scopus: 40
    Greedy Randomized Adaptive Search Procedure for Simultaneous Scheduling of Production and Preventive Maintenance Activities in Dynamic Flexible Job Shops
    (Springer, 2021-08-03) Baykasoglu, Adil; Madenoglu, Fatma S.
    In the present study, we proposed a greedy randomized adaptive search procedure (GRASP) for integrated scheduling of dynamic flexible job shops with a novel preventive maintenance policy. In most of the real-life scheduling practices, unexpected and unknown events occur frequently, which necessitates solving operations and maintenance scheduling problems dynamically. Dynamic events like new order arrival, machine breakdown, changes in due date, order cancellation, and urgent order are considered in this study. Moreover, order acceptance/rejection decisions and an order review release mechanism are also taken into account in order to enhance the overall performance by adjusting capacity regarding to customer due date requirements. Four objectives namely mean tardiness, schedule instability, makespan, and mean flow time are considered within a lexicographic programming logic. Random test instances are generated for the stated dynamic scheduling problem. In order to confirm the applicability of the proposed GRASP-based algorithm, extensive experiments were also conducted on well-known job shop scheduling benchmark instances and flexible job shop scheduling benchmark instances with preventive maintenance activities. Computational experiments conducted under various experimental settings such as flexibility level and due date tightness in addition to different preventive maintenance policies. To the best of our knowledge, the present study presents the first attempt through GRASP for simultaneous dynamic scheduling of operations and preventive maintenance activities in flexible job shops. Results of the extensive computational experiments demonstrate that simultaneous scheduling of manufacturing operations and preventive maintenance activities is a viable and effective approach for performance improvement in dynamic flexible job shop scheduling environments.
  • Article
    Citation - WoS: 13
    Citation - Scopus: 16
    Clarification of Pomegranate Juice Using PSF Microfiltration Membranes Fabricated With Nano TiO2and Al2O3
    (Wiley, 2020-06-22) Severcan, Solmaz Sebnem; Uzal, Nigmet; Kahraman, Kevser
    Microfiltration (MF) membranes were fabricated using PSF/PEI (17/2 wt%) with TiO(2)and Al(2)O(3)nanoparticles to enhance pomegranate juice clarification performance. The membrane performances were tested using dead-end filtration system. Membranes were characterized by Scanning Electron Microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), porosity, water contact angle, and pure water flux experiments. All MF membranes had higher porosity, pure water flux, and hydrophilicity.SEMimages of the membranes proved the nanoparticle incorporation to the PSF/PEI matrix. The quality of clarified pomegranate juice samples using PSF/PEI nanocomposite membranes were better than that of clarified using both commercial and unmodified membranes. The highest performance for the clarification of pomegranate juice samples was obtained for 0.05% of Al(2)O(3)incorporated PSF/PEI membranes with the highest color (5,781 +/- 4 PtCo), total soluble solid (16.2 +/- 0.0 Brix), total phenolic content (2,642.1 +/- 46.4 mg GAE/L), antioxidant activity (ABTS: 62.4 +/- 0.2 TEAC/L, DPPH: 41.3 +/- 0.0 TEAC/L) and total monomeric anthocyanin (100.7 +/- 1.7 mg/L). Practical applications Utilization of membrane technology in food industry has been increased rapidly in the past two decades. Due to their advantage in terms of saving color pigments, MF membranes are more suitable than UF ones for clarification of pomegranate juice. Incorporation of nanoparticles to the membrane matrix is one of the methods to increase the antifouling character and the strength of the membranes modified with hydrophilic polymers. There are some studies investigating the effect of TiO(2)and Al(2)O(3)nanoparticles on the properties of polymeric membranes. However, there are no reported data on the utilization of TiO(2)and Al(2)O(3)nanocomposite membranes for clarifying pomegranate juice. In this study, TiO(2)and Al(2)O(3)incorporated new generation PSF/PEI membranes were utilized in the clarification process of pomegranate juice for the first time in the literature. The results showed that Al(2)O(3)incorporation seems to be a good alternative for clarifying pomegranate juice with enhanced quality parameters.
  • Article
    Citation - WoS: 24
    Citation - Scopus: 24
    Circular RNA-MicroRNA Interaction Predictions in SARS-CoV Infection
    (Walter de Gruyter Gmbh, 2021-03-01) Demirci, Yilmaz Mehmet; Demirci, Muserref Duygu Sacar; Saçar Demirci, Müşerref Duygu
    Different types of noncoding RNAs like MicroRNAs (miRNAs) and circular RNAs (circRNAs) have been shown to take part in various cellular processes including post-transcriptional gene regulation during infection. MiRNAs are expressed by more than 200 organisms ranging from viruses to higher eukaryotes. Since miRNAs seem to be involved in host-pathogen interactions, many studies attempted to identify whether human miRNAs could target severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNAs as an antiviral defence mechanism. In this work, a machine learning based miRNA analysis work flow was developed to predict differential expression patterns of human miRNAs during SARS-CoV-2 infection. In order to obtain the graphical representation of miRNA hairpins, 36 features were defined based on the secondary structures. Moreover, potential targeting interactions between human circRNAs and miRNAs as well as human miRNAs and viral mRNAs were investigated.