Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
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Article Citation - WoS: 7Citation - Scopus: 7Villages in the City - Urban Planning for Neighbourhood Love(Wiley, 2024-03-17) Kourtit, Karima; Nijkamp, Peter; Turk, Umut; Wahlstrom, MiaThe city comprises of a wide variety of heterogeneous territorial units (e.g. districts or neighbourhoods). In many - especially larger - cities, social capital assets (like community bonds) are mirrored at the level of neighbourhoods which form the home for many sociocultural communities or distinct socio-economic classes. We postulate in this study that the big city is essentially an 'archipelago' made up of 'urban villages'. We analyse the residents' perceived attractiveness regarding their daily local neighbourhood by introducing the concept of 'village love' (or 'neighbourhood love'), inspired by the recent literature on 'city love' (comprising 'body', 'soul' and 'community' constituents of urban life). Based on an extensive and detailed multi-annual database for all neighbourhoods in Rotterdam, the present paper seeks to identify the background factors shaping 'village love' in the city, with particular attention to the citizens' subjective appreciation for and access to a great variety of (physical and immaterial) urban amenities shaping the place-based satisfaction of residents. The theoretical framing of our research resembles the basics of traditional central place theory here transmitted to the urban space in which local proximity to amenities plays a key role. A wide array of relevant amenities impacting on the place-specific well-being feelings ('village love') of residents in various neighbourhoods in the city of Rotterdam is distinguished using inter alia-rich multi-annual survey data. This approach is empirically tested and verified by means of LISA statistics and advanced spatial econometric dependence models ('urbanometrics'). The findings confirm the usefulness of a central place interpretation of 'urban village love' in the city. 'Villages in the City - Urban Planning for Neighbourhood Love': This study advocates that cities are composed of interconnected 'urban villages', each with its own social capital and community bonds. Using extensive data from Rotterdam, we investigate the factors influencing residents' perceived attractiveness and satisfaction with their local neighbourhoods. Our analysis highlights the importance of access to diverse amenities in shaping residents' sense of 'village love'. Through spatial econometric models, the study confirms the central place interpretation of 'urban village love' in the city, shaping future urban planning strategies for fostering vibrant and cohesive communities.imageArticle Citation - WoS: 6Citation - Scopus: 6Uncovering Nanoclusters in Amorphous AlN: An Ab Initio Study(Wiley, 2014-12-22) Durandurdu, MuratAmorphous AlN (a-AlN) is modeled by melt-and-quench technique using ab initio molecular dynamic simulations. For the first time, three-dimensional hexagonal-like nanoclusters embedded in amorphous matrix are proposed for a-AlN. The model is chemically ordered and dominantly fourfold coordinated, but its short-range order is partially different from the crystalline morphology due to the nanoclusters. The model is semiconducting with a theoretical band gap of 1.7eV.Article Citation - WoS: 6Citation - Scopus: 6Two Successive Amorphous-to Phase Transformations in TiO2(Wiley, 2017-05-22) Durandurdu, MuratBased on constant pressure ab initio simulations, we propose, for the first time, two successive amorphous-to-amorphous phase transformations for TiO2. The first one is a gradual phase transformation from a low-density amorphous phase to a high-density amorphous phase, whereas the second one is a first-order phase transformation from the high-density amorphous phase to a very high-density amorphous phase. The low-density amorphous to high-density amorphous phase change is irreversible, whereas the high-density amorphous to very high-density amorphous phase transformation is reversible. The high-density amorphous and very high-density amorphous phases consist of differently coordinated configurations. The sevenfold and ninefold-coordinated arrangements formed in amorphous TiO2 under pressure are similar to the main building motif of the baddeleyite and cotunnite polymorphs of TiO2, respectively, while the eightfold-coordinated configuration is different from the local structure of the cubic TiO2 phase. The electronic structure calculations suggest that both dense amorphous phases present a semiconducting character with a band gap energy less than that of the original low-density amorphous phase.Article Citation - WoS: 4Citation - Scopus: 6Traffic Aware Cyclic Sleep-Based Power Consumption Model for a Passive Optical Network(Wiley, 2022-02-28) Butt, Rizwan Aslam; Faheem, Muhammad; Anwar, Muhammad; Mohammadani, Khalid H.; Idrus, Sevia M.For a network, a power consumption model is an important tool to test the performance of a network process for different traffic loads. In a Passive optical network (PON), the optical network unit (ONU) is responsible for the major power consumption of PON. Both IEEE and ITU have standardized a cyclic sleep process (CSP) for ONU energy conservation. In next-generation PON; TWDM and XGS PON, the ONU power contribution has increased further due to higher number of ONUs and ONU being tunable. Therefore, an accurate power consumption model of the CSP process for energy efficiency studies under different traffic conditions is of prime importance. The existing CSP power consumption models do not depict the CSP process accurately especially the inactivity of the ONU in the asleep and sleep aware states are not taken into account which reduce the accuracy of the model. The proposed inactivity aware model (IAM) overcomes these gaps and very accurately models the CSP process, as evident from the results, which are better than earlier model results and quite close to earlier published simulation results. The model is also validated through a simulation-based study and the simulation results are observed to be very close to the model results with only a 5% deviation.Article Citation - WoS: 6Citation - Scopus: 6The Different Impacts of g-C3N4 Nanosheets on PVDF and PSF Ultrafiltration Membranes for Remazol Black 5 Dye Rejection(Wiley, 2023-08-02) Senol-Arslan, Dilek; Gul, Ayse; Dizge, Nadir; Ocakoglu, Kasim; Uzal, NigmetMembranes combined with nanoparticles are an excellent combination capable of successfully removing various contaminants, such as dyes from wastewater while using very little energy and decreasing pollution. The present study reports an efficient approach for Remazol Black 5 (RB5) dye removal using composite graphitic carbon nitride nanosheets (g-C3N4), polysulfone (PSF), and polyvinylidene fluoride (PVDF) membranes. The membranes were prepared using the phase inversion method, with varying quantities of g-C3N4 nanosheets ranging from 0.1%, 0.2% to 0.3%. The prepared g-C3N4 nanosheets were characterized by FTIR, SEM analyses, and zeta potential measurements. FTIR and SEM studies, contact angle, water permeability, COD, and dye rejection measurements were used to characterize the g-C3N4 nanosheets embedded in PSF and PVDF membranes. After the addition of 0.3 wt% g-C3N4, the water flux of the 0.3 wt% g-C3N4 embedded PSF membrane was the highest, whereas the water flux of the 0.3 wt% g-C3N4 embedded PVDF membrane was the lowest. The ultrafiltration (UF) membrane's performance with g-C3N4 embedded showed an RB5 rejection rate of more than 80% and a COD removal efficiency of more than 45%. The results of the experimental filtration showed that RB5 rejection reached maximum values of 91.3% for 0.1 wt% g-C3N4/PSF, and 85.6% for 0.3 wt% g-C3N4/PVDF.Article Citation - WoS: 6Citation - Scopus: 6Tetrahedral Amorphous Boron Nitride: A Hard Material(Wiley, 2019-09-25) Durandurdu, MuratWe generate a tetrahedrally coordinated amorphous boron nitride (BN) model by means of first principles molecular dynamics calculations and report its mechanical and electrical properties in detail. The amorphous configuration is almost free from chemical disorder and consists of about 20% coordination defects, similar to tetrahedral (diamond-like) amorphous carbon. Its theoretical band gap energy is about 2.0 eV, less than 4.85 eV estimated for cubic BN. The bulk modulus and Vickers hardness of tetrahedral amorphous BN are computed as 206 GPa and 28-35 GPa, respectively. Based on these findings, we propose that tetrahedral noncrystalline BN can serve as electronic and hard materials as well.Article Citation - WoS: 28Citation - Scopus: 35Tactile Sensitivity and Capability of Soft-Solid Texture Discrimination(Wiley, 2015-08-09) Aktar, Tugba; Chen, Jianshe; Ettelaie, Rammile; Holmes, MelvinThe sensation and perception of food texture is regulated by tactile-dominated mechanisms and therefore, it is believed that one's capability in discriminating food textural properties could be related to one's tactile sensitivity. However, evidence to support this hypothesis is currently not available. This work aims to test this hypothesis by examining tactile sensitivity of individuals' (touch detection threshold and two-point discrimination threshold) and texture discrimination capability. A range of soft-solid food samples with controlled firmness and elastic moduli were designed for textural discrimination tests. A total of 32 healthy subjects threshold of touch detection was found to be 0.028 g for the fingertip and 0.013 g for the tongue. Similarly, the mean threshold of two-point discrimination was 1.42 mm and 0.62 mm for the fingertip and tongue, respectively. Threshold for firmness discrimination (compressing until yielding) of the gel samples was 13.3% for the fingertip and 11.1% for the tongue. However, the elasticity discrimination threshold (by gentle pressing) of the population was found to be much smaller at 2.3% and 1.2% for the fingertip and the tongue respectively. Results show that tongue is slightly more sensitive than the fingertip in discriminating food texture (P < 0.05). An expected correlation between individual's capability of texture discrimination and their tactile sensitivity was not observed. PRACTICAL APPLICATIONS Texture discrimination capability is a significant factor for food texture preference and appreciation. In order to understand texture perception, it is essential to identify the relevant factors and define characteristics that govern the processes involved. Having a meaningful and reliable texture discrimination indicator is critically important for the food industry in the development and optimization of new food products, and in particular for specific food design for individuals' with special needs, e.g., elderly, dysphagic patients, etc. With this study, we illustrate the differential threshold for soft-solid texture (firmness and elasticity) and also investigate the capabilities of tactile sensation (touch detection and two-point discrimination) and evaluate potential correlations. The results and correlations may provide information about texture sensitivity and also might provide useful information to R&D researchers. Methodologies could also be applied in general food sensory studies and also investigating relationships between sensory psychology and sensory physiology.Article Citation - WoS: 6Citation - Scopus: 7Sustainability Assessment of Denim Fabric Made of PET Fiber and Recycled Fiber From Postconsumer PET Bottles Using LCA and LCC Approach With the EDAS Method(Wiley, 2024-11-01) Fidan, Fatma Sener; Aydogan, Emel Kizilkaya; Uzal, NigmetThe textile industry is under pressure to adopt sustainable production methods because its contribution to global warming is expected to rise by 50% by 2030. One solution is to increase the use of recycled raw material. The use of recycled raw material must be considered holistically, including its environmental and economic impacts. This study examined eight scenarios for sustainable denim fabric made from recycled polyethylene terephthalate (PET) fiber, conventional PET fiber, and cotton fiber. The evaluation based on the distance from average solution (EDAS) multicriteria decision-making method was used to rank scenarios according to their environmental and economic impacts, which are assessed using life cycle assessment and life cycle costing. Allocation, a crucial part of evaluating the environmental impact of recycled products, was done using cut-off and waste value. Life cycle assessments reveal that recycled PET fiber has lower freshwater ecotoxicity and fewer eutrophication and acidification impacts. Cotton outperformed PET fibers in human toxicity. Only the cut-off method reduces potential global warming with recycled PET. These findings indicated that recycled raw-material life cycle assessment requires allocation. Life cycle cost analysis revealed that conventional PET is less economically damaging than cotton and recycled PET. The scenarios were ranked by environmental and economic impacts using EDAS. This ranking demonstrated that sustainable denim fabric production must consider both economic and environmental impacts. Integr Environ Assess Manag 2024;00:1-19. (c) 2024 The Author(s). Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).Article Citation - WoS: 6Citation - Scopus: 6Surface Coating of Polyamide Reverse Osmosis Membranes With Zwitterionic 3-(3,4 (l-DOPA) for Forward Osmosis(Wiley, 2019-03-27) Saki, Seda; Uzal, NigmetTo overcome low permeability and fouling problems of membranes used in FO processes, modification is needed to improve the hydrophilicity, permeability and selectivity of membranes. In this work, thin film composite (TFC) commercial polyamide RO membranes (BW30-LE, SW30-HR, AG and AC) were functionalized with zwitterionicl-DOPA. The effect ofl-DOPA on the morphology of membranes was determined via SEM, FT-IR, AFM and contact angle analysis. Thel-DOPA modified BW30-LE membrane showed excellent properties with 46 degrees contact angle and 3.8 L/m(2)hbar water permeability and 0.83 L/m(2)h salt permeability. Although,l-DOPA modified BW30-LE membrane had the highest water flux and hydrophilicity,l-DOPA modified SW30-HR membrane showed higher FO flux with 9.38 L/m(2)h than BW 30 membrane with 3.5 L/m(2)h at 50 g/L NaCl draw solution. Introducing hydroxyl and carboxyl ionic groups on the membrane surface withl-DOPA coating enhanced the FO performance and water permeability which provide a new insight in FO applications.Conference Object Citation - WoS: 25Citation - Scopus: 26Semiconducting Copolymers Based on Meso-Substituted BODIPY for Inverted Organic Solar Cells and Field-Effect Transistors(Wiley, 2017-12-11) Ozdemir, Mehmet; Kim, Sang Woo; Kim, Hyungsug; Kim, Myung-Gil; Kim, Bumjoon J.; Kim, Choongik; Usta, HakanThe synthesis, physicochemical, and optoelectronic properties of a new class of low band-gap (approximate to 1.3 eV) donor-acceptor copolymers based on a highly electron-deficient meso-5-(2-octyldodecyl)thiophene-substituted BODIPY pi-unit are presented. The polymeric solutions exhibit strong aggregation-dependent excitonic properties indicating the presence of enhanced pi-coherence as a result of strong interchain interactions. The polymeric semiconductor thin films prepared by spin coating show isotropic nodule-like grains with essentially no ordering in the out-of-plane direction. Field-effect hole mobilities of 0.005 cm(2) V-1.s(-1) are observed in bottom-gate top-contact organic field-effect transistors, and inverted bulk-heterojunction organic photovoltaics employing the polymer:PC71BM active layer exhibit excellent power conversion efficiencies of 6.2% with a short-circuit current of 16.6 mA cm(-2). As far as it is known, this is a record high value achieved to date for a boron-containing donor polymer in the photovoltaic literature indicating a significant enhancement in power conversion efficiency (>3-4 times). The findings clearly present that rationally designed BODIPY-based donor-acceptor copolymers can be a key player in photovoltaic applications.