Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
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Article Citation - WoS: 38Citation - Scopus: 38pH- and Temperature-Responsive Amphiphilic Diblock Copolymers of 4-Vinylpyridine and Oligoethyleneglycol Methacrylate Synthesized by RAFT Polymerization(Elsevier Sci Ltd, 2014-01) Topuzogullari, Murat; Bulmus, Volga; Dalgakiran, Eray; Dincer, SevilDiblock copolymers of 4-vinylpyridine (4VP) and oligoethyleneglycol methyl ether methacrylate (OEGMA) were synthesized for the first time using RAFT polymerization technique as potential drug delivery systems. Effects of the number of ethylene glycol units in OEGMA, chain length of hydrophobic P4VP block, pH, concentration and temperature on the solution behavior of the copolymers were investigated comprehensively. Copolymer chains formed micelles at pH values higher than 5 whereas unimeric polymers were observed to exist below pH 5, owing to the repulsion between positively charged P4VP blocks. The size of the micelles was dependent on the relative length of blocks, P4VP and POEGMA. Thermo-responsive properties of copolymers were investigated depending on the pH and length of P4VP block. The increase in the length of P4VP block decreased the LCST substantially at pH 7. At pH 3, LCST of copolymers shifted to higher temperatures due to the increased interaction of copolymers with water through positively charged P4VP block. (C) 2013 Elsevier Ltd. All rights reserved.Article Citation - WoS: 39Citation - Scopus: 51What Are the Key Success Factors for Strategy Formulation and Implementation? Perspectives of Managers in the Hotel Industry(Elsevier Sci Ltd, 2020-08) Koseoglu, Mehmet Ali; Altin, Mehmet; Chan, Eric; Aladag, Omer FarukThis study investigates how hotel managers describe strategy and identify key success factors for its formulation and implementation. The study analyzes qualitative data collected through semi-structured interviews with property level top managers of hotels in Hong Kong. The findings show that hotel managers prioritize competition analysis and macro-environmental conditions over internal characteristics such as teamwork in strategy formulation. In the implementation phase, however, internal considerations such as employee involvement and strategic consensus are given prominence. This study provides a significant contribution by examining how top level practitioners in the industry interpret success factors in their strategic management efforts, and it highlights a largely neglected area in the hospitality and tourism management literature.Article Citation - WoS: 12Citation - Scopus: 14The Effect of Different Tabbing Methods on the Damage Progression and Failure of Carbon Fiber Reinforced Composite Material Under Tensile Loading(Elsevier Sci Ltd, 2022-07) Ali, Hafiz Qasim; Yilmaz, Cagatay; Yildiz, MehmetComposites are well-known and widely used materials due to their anisotropic nature and high strength-to-weight ratio; therefore, the mechanical performance of these materials is crucial. Precise tensile testing is essential to obtain material properties that are crucial for the design stage of composite structures. This study is an effort to investigate the effect of adhesive materials used for tabbing process, which is necessary for the tensile testing procedure. Araldite and AF 163-2k film are used as the adhesive film, whereas in the case of AF 163-2k, tabbing is done through two different procedures (Jig and corner holes method). Apart from the tensile per-formance, strain distribution and damage progression are monitored simultaneously using digital image corre-lation (DIC) and acoustic emission (AE) analysis. It is observed that there is no significant difference in the ultimate tensile strength of these composites tabbed with different adhesives and procedures. Nevertheless, the first major failure strength is much higher in Araldite tabbed specimens compared to AF 163-2k film (the first major failure activity is defined as a point at which material loses its integrity, especially when considering structural or aerospace applications). Also, strain distribution throughout the gauge length recorded via DIC is appreciably different, which is attributed to damage accumulation and progression monitored by AE analysis. The frequency-based analysis of AE data is performed to classify the damage, and cumulative energy is correlated with the DIC to navigate the failure activity at different times and stress levels.Article Citation - WoS: 30Citation - Scopus: 39Strategy Implementation Research in Hospitality and Tourism: Current Status and Future Potential(Elsevier Sci Ltd, 2020-07) Aladag, Omer Faruk; Koseoglu, Mehmet Ali; King, Brian; Mehraliyev, FuadTo achieve their business objectives, hospitality and tourism organizations need effective implementation as well as consistent strategy formulation. However, the implementation aspect of strategy has attracted relatively less scholarly interest than strategic planning despite its critical role in achieving performance outcomes. Consequently, it is timely to provide an in-depth analysis of the strategy implementation literature. This is particularly the case in hospitality and tourism management where comprehensive literature reviews of strategy implementation have been lacking. To address the knowledge gap, the authors conduct a systematic literature review of 139 articles that appeared in 42 journals over the period 1988-2019. The items were grouped into six topic clusters with a view to generating novel research questions that have the potential to advance the field. We identify four main gaps that should be addressed and suggest prospective research directions.Article Citation - WoS: 2Citation - Scopus: 2Route Choice to Inform Navigation System Design and Accessibility Analysis for Older Pedestrians: A Scoping Review(Elsevier Sci Ltd, 2025-10) Fulman, Nir; Huber, Johannes; Lloyd, Armagan Teke; Foshag, Kathrin; Grinblat, Yulia; Turk, Umut; Zipf, AlexanderIntroduction: Routing systems can support older adults by helping them overcome barriers to walking, promoting independence and well-being. The paths generated by these systems also inform urban accessibility metrics, such as those used in 15-min-city planning. Yet current systems rarely reflect the preferences or constraints of older pedestrians. Empirical studies of route choice can help close this gap by revealing how people trade off different route attributes in real settings. Methods: We conducted a scoping review, following PRISMA-ScR guidelines, of empirical studies analyzing pedestrian route choice among adults. The goal was to identify findings that could inform the design of more age-inclusive routing tools. Results: Eleven studies met the inclusion criteria, eight of which focused exclusively on older adults. Despite varied contexts, three consistent themes emerged: (i) sidewalk quality and manageable gradients; (ii) aesthetic and sensory comfort, including greenery, low noise, and good lighting; and (iii) access to benches, transit, and everyday amenities. However, most studies relied on qualitative methods, limiting direct integration into routing algorithms. Conclusions: Future work should prioritize hybrid qualitative-quantitative designs, large-scale sampling of routes, and fine-grained mapping of micro-barriers. Analyses should account for age, gender, and functional ability, and consider circular leisure walks as a distinct travel pattern. These directions can enhance the usability and equity of routing systems and urban planning frameworks.Article Citation - WoS: 31Citation - Scopus: 31Revisiting the Nexus Among Carbon Emissions, Energy Consumption and Total Factor Productivity in African Countries: New Evidence from Nonparametric Quantile Causality Approach(Elsevier Sci Ltd, 2020-03) Dogan, Eyup; Tzeremes, Panayiotis; Altinoz, BuketThis study aims to contribute to the existing thin body of nonlinear causality literature by applying the new hybrid nonparametric quantile causality approach. In this line, we investigate the non-linear nexus among total factor productivity, energy consumption and carbon emissions for seventeen African countries. From the results, it is remarkable that there are generally strong causalities between the variables in the middle lower, middle upper and middle quantiles. Hence, energy consumption, environmental pollution and total factor productivity are closely linked in African countries. In particular, bidirectional linkage is detected between total factor productivity and energy consumption for Angola, Benin, Botswana, Cote d'Ivoire, Kenya, Morocco, Egypt, Nigeria and Tunisia. Studying the relationship between total factor productivity and emissions again at the middle quantile bidirectional causal ordering is documented almost for all the countries. Lastly and regarding the linkage between energy consumption and carbon emissions, a strong bidirectional ordering between the two variables is confirmed for Angola, Benin, Cote d'Ivoire, Cameroon, Kenya, Morocco, Egypt, Mozambique, Nigeria, Senegal and Tunisia. We can notice that an increase in economic development is critical for these countries; a number of regulatory policies for environmental problems and energy consumption are required during this development.Article Citation - WoS: 16Citation - Scopus: 18Piezoresistivity and Piezopermittivity of Cement-Based Sensors Under Quasi-Static Stress and Changing Moisture(Elsevier Sci Ltd, 2024-04) Zhang, Jiacheng; Heath, Andrew; Ball, Richard J.; Chen, Binling; Tan, Linzhen; Li, Guisheng; Paine, KevinIntegrated cement-based sensors offer an economic alternative to extrinsic sensors for health monitoring applications in concrete structures due to their high strength to cost ratio, geometrical versatility, low shrinkage, and natural compatibility. Nonetheless, their performance under in-service conditions were in lack of investigations. While the piezoresistivity (change in resistance with stress) has been commonly used for mechanical sensing, the piezopermittivity (change in capacitive reactance with stress) is rarely characterized. Exploiting the high relative permittivity and electrical conductivity of carbon fibre reinforced cement-based sensors, this study investigates the piezoresistivity and piezopermittivity under changing stress and moisture using electrochemical impedance spectroscopy (EIS). Two types of sensors were evaluated: one containing 0.5 vol% of carbon fibres whose electrical conductivity was ionically dominant, and another with electronically dominant (1.2 vol% of carbon fibres) conductivity. Results highlighted that the piezopermittivity is "moisture content-dominant" whilst the piezoresistivity is "fibre content-dominant". As the moisture content decreased, the sensitivity of piezopermittivity for both sensor types decreased, while the sensitivity of piezoresistivity decreased for the ionically dominant sensor but increased for the electronically dominant sensor. The piezoresistivity of the electronically dominant sensor was less sensitive than piezopermittivity at a water saturation of 80%. Conversely, the piezoresistivity of the ionically dominant sensor was more sensitive than piezopermittivity at the tested water saturations <= 80%. For the first time, this study presents the combined effects of moisture and fibre content on the pressure sensitive response of cement-based sensors through a dual-phase (i.e., piezoresistivity and piezopermittivity) EIS interpretation technique, providing valuable information to benefit further behaviour prediction and single-effect recognition in the field scenario where the sensors are subject to simultaneousArticle Citation - WoS: 38Citation - Scopus: 41Ozonation Pre and Post-Treatment of Denim Textile Mill Effluents: Effect of Cleaner Production Measures(Elsevier Sci Ltd, 2016-11) Morali, E. Kaan; Uzal, Nigmet; Yetis, UlkuDenim production, which is one of the leading sub-sectors of textile industry that generates considerable amount of wastewater with high pollution load both from dyeing and finishing processes. This sub-sector is therefore to consider cleaner production opportunities for these processes to reduce its wastewater generation and pollution load. In a denim-producing plant, the wastewater treatability studies have revealed that the most technically applicable cleaner production alternatives are caustic recovery from alkaline finishing wastewaters, and reuse of indigo dyeing wastewaters via the application of membrane filtration. In the present study, impact of the changes in the final effluent quality due to the foreseen cleaner production measures were considered in reference to the evaluation of impact on ozonation treatment of the effluent from a denim-producing plant. Ozonation was applied as pretreatment to the effluent from the plant before the foreseen measures (chemical oxygen demand, COD = 2750 mg/L; color = 3950 Pt-Co), and to the simulated effluent after the foreseen measures (COD = 3100 mg/L; color = 4500 Pt-Co); and also as post-treatment to the biologically treated effluent (COD = 800 mg/L; color = 3700 Pt-Co) before the foreseen measures. When applied to the effluent before the foreseen measures as pretreatment, ozonation provided 86% color and 46% COD removal with 3240 mg/h ozone dose in 70 min. However, less satisfactory results were obtained with the wastewater after the measures; with 86% color and 31% COD removals at 3960 mg/h ozone dose in 80 min. In parallel to the decrease observed in COD removal, ozone consumption was also much higher than that for the wastewater before the cleaner production measures. The findings have indicated that the environmental benefits to be brought by cleaner production measures have to be balanced against the risks to be encountered in the treatment of the final effluent. (C) 2016 Elsevier Ltd. All rights reserved.Article Citation - WoS: 20Citation - Scopus: 19Origins, Evolution and Themes of Scholarly Hospitality Sources: 1960-2019(Elsevier Sci Ltd, 2021-04) Koseoglu, Mehmet Ali; Mehraliyev, Fuad; Aladag, Omer Faruk; King, BrianThis paper provides an overview and insight into the intellectual foundations and evolution of hospitality scholarship. The authors found that hospitality research has exhibited certain defining and evolving characteristics when an extended period - six decades - is considered. Quantitative methods have predominated with ongoing efforts to reach agreement about the most valid and applicable research methods. Four of the six identified research domains are marketing related, each with its defining characteristics. Some domains are heavily reliant on sources from work originally published in "mainstream" literature such as marketing, though the fast-developing field of online reviews draws sources overwhelmingly from the hospitality and tourism journals. The paper contributes to theory by synthesizing key theoretical concerns over six decades. It also evidences the shift of hospitality scholarship from its pragmatic and operational origins to a stronger theory base offering practitioners an important reference point when confronting unprecedented industry upheavals.Article Citation - WoS: 13Citation - Scopus: 16Inequality in Leisure Mobility: An Analysis of Activity Space Segregation Spectra in the Stockholm Conurbation(Elsevier Sci Ltd, 2023-07) Toger, Marina; Turk, Umut; Osth, John; Kourtit, Karima; Nijkamp, PeterLeisure mobility forms an important part of people's spatial activity and mobility spectrum. This study aims to analyse the inequality dimensions of spatial mobility of individuals who seek to move to recreational and leisure destinations (often 'green' and 'blue') on designated days. The study traces - through the use of spatially dependent multilevel models - the mobility patterns of people from the greater Stockholm area, using individual pseudonymised mobile phone data and other publicly accessible data. We find significant socio-demographic inequalities in the observed residents' spatial leisure choices, where less affluent groups display especially low variation in mobility when comparing between weekdays, weekends, vacation season and work-periods.