01. Araştırma Çıktıları | TR-Dizin | WoS | Scopus | PubMed

Permanent URI for this communityhttps://hdl.handle.net/20.500.14365/1

Browse

Now showing 1 - 20 of 753

Citation - WoS: 1
Citation - Scopus: 2
2d Model of a Biomass Single Particle Pyrolysis-Analysis of the Influence of Fiber Orientation on the Thermal Decomposition Process
(Mdpi, 2025) Hercel, Paulina; Orhon, Atahan; Jozwik, Michal; Kardas, Dariusz
Understanding the influence of heat transfer on the pyrolysis process is crucial for optimizing industrial biofuel production processes. While numerous scientific studies focus on experimental investigations of pyrolysis using laboratory-scale devices, many neglect the essential role of thermal energy in initiating and controlling thermal decomposition processes. This study presents a transient two-dimensional numerical model of biomass single-particle pyrolysis, which includes the energy balance, mass conservation equations and pyrolysis gas pressure and velocity equations. The model employs explicit numerical methods to manage the high computational demands of 2D transient simulations, but is successfully validated with the use of experimental data found in the literature. The model reflects the heterogeneous structure of wood by using different thermal conductivity coefficients depending on the wooden fibers' orientation. The results demonstrate the impact of fiber orientation on the heat transfer and thermal decomposition processes. The anisotropic properties of wood led to varied temperature fields and pyrolysis decomposition stages, aligning well with experimental data, thus validating the model's accuracy. The proposed approach can provide a better understanding and lead to improvement in biofuel production processes, enabling more efficient and controlled conversion of biomass into fuel. By optimizing the pyrolysis process, it contributes to the development of sustainable energy preservation and regeneration methods, supporting a shift towards more sustainable fuel production patterns using renewable biomass resources like wood.
Citation - WoS: 4
Citation - Scopus: 5
3d Helmholtz Coil System Setup for Thermal Conductivity Measurements of Magnetic Nanofluids
(Pergamon-Elsevier Science Ltd, 2023) Alsangur, Rahime; Dog, Serkan; Ateş, Ismet; Turgut, Alpaslan; Çetin, Levent
This study aims to design a mechatronic system that involves a 3D Helmholtz coil system implemented with the 3 omega; method to measure the thermal conductivity of magnetic nanofluids under uniform and rotating magnetic fields. For this purpose, a 3D Helmholtz coil system was designed and manufactured to generate a uniform and rotating magnetic field up to 400 G. First, the uniformity and rotation abilities of the magnetic field generated by the system were investigated numerically and experimentally. The investigations pointed out that the 3D Helmholtz coil system can generate a uniform magnetic field in 1D, 2D, and 3D with a maximum non-uniformity factor of 0.0016. After that, the thermal conductivity of Fe3O4 - water magnetic nanofluid samples with 1, 2, 3, 4, and 4.8 vol.% were measured under 1D, 2D, and 3D uniform magnetic field application. The magnetic field was applied at different direction angles between X, Y, and Z axes in the Cartesian coordinate system. The results pointed out that the thermal conductivity of the samples increases as the magnetic field and particle concentration increase. The maximum thermal conductivity enhancement was observed as similar to 9.1% and the minimum thermal conductivity was observed as similar to 1.9% when the magnetic field is applied in parallel and perpendicular directions, respectively. The measurement results also pointed out that under the external uniform magnetic field application at 2D and 3D, thermal conductivity enhancement is less affected by the particle concentration increment.
Citation - WoS: 5
Citation - Scopus: 6
Achieving Turkey's Indc Target: Assessments of Nccap and Indc Documents and Proposing Conceivable Policies
(Mdpi, 2018) Alkan, Ayla; Oğuş Binatlı, Ayla; Deger, Cagacan
In 2015, Turkey submitted its Intended Nationally Determined Contribution (INDC) to the United Nations Framework on Climate Change Convention (UNFCCC) before the Paris Conference of the Parties (COP 21), expressing its intention to decrease emissions level at a rate of 21% from business as usual. This emissions reduction target is important as it is the first one for Turkey. However, Turkey faces unemployment problems and needs to sustain its growth. In this study, an Environmentally Extended Social Accounting Matrix (SAM), based on 2012 Input-Output data, was created, emissions reduction potentials of the National Climate Change Action Plan (NCCAP) together with the INDC were calculated, and alternative policies to reduce emissions to the target level and to boost the economy were proposed separately. The study finds that both the preparation and implementation of the previous national documents are problematic, and that Turkey was not meticulous about implementation of the climate mitigation policies in the previous national documents. The study also finds that reaching the emissions target with the INDC policies seems impossible and more conceivable policies are needed, and recommends that the INDC target and document itself should be revised substantially.
Citation - WoS: 2
Citation - Scopus: 2
Active Vibration Control of Cantilever Structures by Integrating the Closed Loop Control Action Into Transient Solution of Finite Element Model and an Application To Aircraft Wing
(Mdpi, 2025) Bulbul, Ilker; Akdag, Murat; Karagulle, Hira
In this study, the active vibration control (AVC) of a cantilever beam with an end mass is considered first and studied experimentally and through simulation. The Laplace transform method, Newmark method, and ANSYS are used for simulations. An impulse force applied to the mass and the velocity actuation applied to the base are assumed to be disturbance and controlling input, respectively. The displacement of the mass is taken as the feedback signal in simulations. Four strain gauges are located near the bottom point, connected with a Wheatstone bridge, and the output voltage of a load-cell amplifier (LCA) is used as the feedback signal in experiments. Strain feedback is considered in experiments because it is easy to implement, cost-effective, and can be used in applications. Experimental displacement signals obtained from the top of the beam are compared with the output signals from LCA and it is observed that they are approximately linearly dependent. Velocity input is generated with a servo motor-driven linear actuator in experiments. The closed loop control is achieved by a personal computer with an Adlink-9222 PCI DAQ card and a C program in the experiments. The integration of the closed loop control action into the transient solution with Newmark method and ANSYS is implemented in simulations. The input reference value is taken as zero for vibration control. The instantaneous value of the feedback signal at a time step is subtracted from zero to find the error signal value and the error value is multiplied by the control gain to calculate the controlling signal. The simulation results obtained with the Newmark method and ANSYS are in good agreement with the analytical results obtained with Laplace transform method. Simulation results are also in acceptable agreement with the experimental results for explaining the behavior of the success of AVC depending on the control gain, Kp. After verifying ANSYS solutions, the ANSYS procedure is applied to an aircraft wing as a real complex cantilever structure. The wing, with a length of 810.8 mm, 13 ribs with a length of 300 mm, and NACA 4412 airfoil, is considered in this study. It is observed that the AVC of real engineering structures can be simulated by integrating control action into transient solution in ANSYS.
Citation - WoS: 61
Citation - Scopus: 69
Adaptation To Five Metres of Sea Level Rise
(Routledge Journals, Taylor & Francis Ltd, 2006) Tol, Richard S. J.; Bohn, Maria; Downing, Thomas E.; Guillerminet, Marie-Laure; Hizsnyik, Eva; Kasperson, Roger; Lonsdale, Kate
There is an unknown but probably small probability that the West-Antarctic Ice Sheet (WAIS) will collapse because of anthropogenic climate change. A WAIS collapse could cause a 5-6 metre global sea level rise within centuries. In three case studies, we investigate the response of society to the most extreme yet not implausible scenario, a five-metre sea level rise within a century, starting in 2030. The case studies combine a series of interviews with experts and stakeholders with a gaming workshop. In the Rhone delta, the most likely option would be retreat, with economic losses, perhaps social losses, and maybe ecological gains. In the Thames estuary, the probable outcome is less clear, but would probably be a mix of protection, accommodation and retreat, with parts of the city centre turned into a Venice of London. A massive downstream barrier is an alternative response. In the Rhine delta (the Netherlands), the initial response would be protection, followed by retreat from the economically less important parts of the country and, probably, from Amsterdam Rotterdam metropolitan region as well. These impacts are large compared to other climate change impacts, but probably small compared to the impacts of the same scenario in other parts of the world. This suggests that the possibility of a anthropogenic-climate-change-induced WAIS collapse would strengthen the case for greenhouse gas emission reduction.
The Adaptiveness of Emotion Regulation Strategies in American and Turkish Young Adults
(John Wiley & Sons Ltd, 2024) Tuna, Ezgi; Chentsova-Dutton, Yulia E.
Citation - WoS: 3
Citation - Scopus: 5
Adhesive Type's Effects on Adhesive Strength of Densified Reinforced Laminated Wood Obtained From Black Poplar (populus Nigra L.)
(North Carolina State Univ Dept Wood & Paper Sci, 2023) Yalçın, İlker; Esen, Raşit
Wood material is the most critical indoor and outdoor building element that has not changed since ancient times. Previous studies have determined that the mechanical properties of tree species with low industrial importance, such as poplar wood, can be improved when they are subjected to the densification process. In addition, it has been determined in studies that the lamination process has a positive effect on the mechanical properties of the wood material. This study aimed to assess the impact of the glue type on the bonding strength during the lamination process of the densified black poplar (Populus nigra L.) using reinforcement material. Wood materials were subjected to densification at 140 degrees C for 10 min. Then, the densified boards were laminated in 3 layers with a reinforcement element (KevlartiD (R), fiberglass, and carbon fiber) between the two wooden boards. It was determined that the best result was obtained with the combination of Akfix polyurethane resin type and carbon fiber reinforcement material (8.49 N/mm2).
Citation - WoS: 12
Citation - Scopus: 10
An Advanced Method With Convergence Analysis for Solving Space-Time Fractional Partial Differential Equations With Multi Delays
(Springer Heidelberg, 2019) Kürkçü, ÖmÜr Kıvanç; Aslan, Ersin; Sezer, Mehmet
This study considers the space-time fractional partial differential equations with multi delays under a unique formulation, proposing a numerical method involving advanced matrix system. This matrix system is made up of the matching polynomial of complete graph together with fractional Caputo and Jumarie derivative types. Also, the derivative types are scrutinized to determine which of them is more proper for the method. Convergence analysis of the method is established via an average value of residual function using double integrals. The obtained solutions are improved with the aid of a residual error estimation. A general computer program module, which contains few steps, is developed. Tables and figures prove the efficiency and simplicity of the method. Eventually, an algorithm is given to illustrate the basis of the method.
Citation - WoS: 94
Citation - Scopus: 103
Affective Interpersonal Touch in Close Relationships: a Cross-Cultural Perspective
(Sage Publications Inc, 2021) Sorokowska, Agnieszka; Saluja, Supreet; Sorokowski, Piotr; Frackowiak, Tomasz; Karwowski, Maciej; Aavik, Toivo; Akello, Grace; Can, Seda
Interpersonal touch behavior differs across cultures, yet no study to date has systematically tested for cultural variation in affective touch, nor examined the factors that might account for this variability. Here, over 14,000 individuals from 45 countries were asked whether they embraced, stroked, kissed, or hugged their partner, friends, and youngest child during the week preceding the study. We then examined a range of hypothesized individual-level factors (sex, age, parasitic history, conservatism, religiosity, and preferred interpersonal distance) and cultural-level factors (regional temperature, parasite stress, regional conservatism, collectivism, and religiosity) in predicting these affective-touching behaviors. Our results indicate that affective touch was most prevalent in relationships with partners and children, and its diversity was relatively higher in warmer, less conservative, and religious countries, and among younger, female, and liberal people. This research allows for a broad and integrated view of the bases of cross-cultural variability in affective touch.
The Afterlife of Critique: The Communicability of Criticism and the Publicity of Polemic Concerning Public Debate in the Turkish Press
(Usc Annenberg Press, 2017) Gürsoy, A. Özgür; Karanfil, Y Gökçen
The philosophical activity of critique is intimately connected with the mundane activity of public criticism that takes place in newspapers. Drawing on the Kantian tradition of critical philosophy, we argue that four axes, namely, self-examination, liminal interrogation, concern with legitimacy, and the requirement of communicability, are implied by critical discourse and public debate. We then examine a recent set of polemics (between Doan Akin, Ali BayramoOlu, and Etyen Mahgupyan) in the Turkish press with the aid of these axes as well as techniques for the analysis of informal reasoning to determine what critical function such polemics may have. We conclude that critique survives as polemic in the Turkish press, but in such a way that the latter's publicity vitiates the former's communicability. The result is that polemics ultimately track the balance of power between social forces rather than being a transformative element within them.
Citation - WoS: 7
Citation - Scopus: 8
Ag-Intercalation of Tm3+/Er3+ Co-Doped Layered Perovskites and Their Exfoliated 2d Nanosheets With an Enhanced Antibiofilm and Antibacterial Activity
(Elsevier, 2022) Gunay, Bensu; Doger, Hilal; Karagonlar, Zeynep Firtina; Saglam, Ozge
There is a significant demand for antibiofilm and antimicrobial materials in the medical device industry. It is well established that Ag-based compounds have a high antimicrobial efficiency. Without being in a lattice, silver's antimicrobial action is mainly mediated by the release of Ag+ ions from the compound. These ions at high levels are toxic to most bacterial species. However, rapidly released Ag+ ions tend to aggregate and lose their anti-bacterial effect over time. Thus, utilizing a new approach for using silver as an antimicrobial agent based on imparting the antimicrobial action through contact, rather than releasing Ag+ ions could be beneficial. Here we report that Ag+ ions intercalation of Tm/Er co-doped layered perovskites and their 2D nanosheets exhibit antibacterial and antibiofilm activities against the human opportunistic pathogens Escherichia coli and Bacillus subtilis. Specifically, flocculation of nanosheets with Ag+ ions had efficient antibacterial and antibiofilm activity at 100 mu g/mL. In addition, the flocculated product demonstrated low in vitro cytotoxicity against the Huh7 hepatocellular carcinoma cell line and HEK 293 embryonic kidney cell line. Our results indicate that Ag-intercalated layered perovskites and the flocculation of the nanosheets hold great promise to be used for anti-microbial and antibiofilm purposes in biomedical engineering applications.
Against Ahistorical Liberalism: the Importance of Acknowledging Past Injustices
(MDPI, 2025) Ozyurt, Deniz Ozbek
Liberal political philosophy has traditionally maintained that history is irrelevant to justice, focusing instead on the present and the future. This perspective renders liberalism largely indifferent to historical injustices, as it prioritizes abstract principles of fairness over considerations of past wrongs. However, contemporary liberal thinkers have increasingly challenged this ahistorical stance, advocating for an approach that acknowledges historical injustices and their enduring effects. This article examines this theoretical debate, emphasizing the importance of remembrance in political philosophy.
Age-Related Alterions in Theta and Alpha Oscillations During Perceptual Reversals
(Elsevier, 2021) Küçük, Kurtulus Mert; Mathes, Birgit; Başar Eroğlu, Canan
[Abstract Not Available]
Age-Related Differences in Alpha Oscillation During the Sustained Attention to Response Task (SART)
(Elsevier, 2025) Ulgen, Zehra; Christina, Schmiedt-Fehr; Guducu, Cagdas; Basar-Eroglu, Canan
Citation - WoS: 6
Citation - Scopus: 6
Agreement Between Tele-Assessment and Face-To Assessment of 30-S Sit-To Test in Patients With Type 2 Diabetes Mellitus
(Springer London Ltd, 2023) Aktan, Ridvan; Yilmaz, Hayriye; Demir, Ismail; Ozalevli, Sevgi
Background The globalization of healthcare systems, and the aim to lower healthcare costs have all contributed to the growth of telehealth technology in recent years. However, before these systems are put into use, their efficacy should be verified. To the best of our knowledge, this is the first study focusing on the evaluation of functional exercise capacity using the 30-s sit-to-stand (30-s STS) test as a tele-assessment method in patients with type 2 diabetes mellitus (T2DM). Aims The purpose of the study is to investigate the level of agreement between tele-assessment and face-to-face assessment of 30-s STS test in patients with T2DM. Methods Fifty participants performed two times 30-s STS tests separated by 1 h: a face-to-face and an Internet-connected video call examination (tele-assessment). Two physiotherapists conduct these evaluations; each was blinded to the other. The order of the evaluations was designated at random for each participant and physiotherapist. Results There was a good level of agreement between tele-assessment and face-to-face assessment of the 30-s STS test (mean differences = 0.20 +/- 0.88, limits of agreement =1.93 to - 1.53). Excellent interrater reliability was found for scores of the 30-s STS test [ICC = 0.93 (95% CI: 0.88; 0.96)]. In addition, all before and after test parameters show that there was a very good interrater reliability (rho >= 0.75). Conclusions This study shows a good level of agreement between tele-assessment and face-to-face assessment of the 30-s STS test. Our study's findings indicate that tele-assessment is a potential application to determine the level of physical capacity remotely in patients with T2DM.
Citation - WoS: 1
Citation - Scopus: 1
The Alevis and Roma/Gypsy in Turkey: Republican Freedom Revisited
(Routledge journals, taylor & francis ltd, 2024) Tamaç, Burak; Yumlu, Oğan; Boyraz, Cemil
This study examines the prospects and limitations of the republican theory of freedom as an analytical tool for analysing Turkey's state of rights and liberties. Following an outline of the main philosophical arguments of republican freedom, which emphasises the link between freedom and non-domination, the paper focuses on the cases of Alevis and Roma-Gypsy populations in Turkey, as two different minority groups that face a unique set of identity problems. The debate on the nature of the discriminatory treatment of certain ethnoreligious groups in Turkey tries, on the one hand, to demonstrate the republican conception's promise to uncover difficulties relating to the status of freedoms. On the other hand, it seeks to highlight potential constraints, especially when it realises socio-economic rights.
Alpha and Theta Brain Oscillations During Visual Perception in Schizophrenia
(Elsevier, 2018) Başar Eroğlu, Canan; Schmiedt-Fehr, C. F.; Ruerup, L. R.; Brand, A. B.; Mathes, B. M.
Alterations of Event-Related Potentials/Oscillations (erps/Eros) in Various Memory Impairments
(Elsevier, 2021) Yener, Görsev
[Abstract Not Available]
Citation - WoS: 20
Citation - Scopus: 25
Alterations of Resting-State Gamma Frequency Characteristics in Aging and Alzheimer's Disease
(Springer, 2023) Güntekin, Bahar; Erdal, Furkan; Bolukbas, Burcu; Hanoglu, Lutfu; Yener, Görsev; Duygun, Rumeysa
Alzheimer's disease (AD) is an important brain disease associated with aging. It involves various functional and structural changes which alter the EEG characteristics. Although numerous studies have found changes in delta, theta, alpha, and beta power, fewer studies have looked at the changes in the resting state EEG gamma activity characteristics in AD. This study aimed to investigate the alterations in the frequency and power values of AD patients' resting-state EEG gamma oscillations compared with healthy elderly and young subjects. We performed Fast Fourier Transform (FFT) on the resting state EEG data from 179 participants, including 59 early stage AD patients, 60 healthy elderly, and 60 healthy young subjects. We averaged FFT performed epochs to investigate the power values in the gamma frequency range (28-48 Hz). We then sorted the peaks of power values in the gamma frequency range, and the average of the identified highest three values was named as the gamma dominant peak frequency. The gamma dominant peak frequency of AD patients (Meyes-opened = 33.4 Hz, Meyes-closed = 32.7 Hz) was lower than healthy elderly (Meyes-opened = 35.5 Hz, Meyes-closed = 35.0 Hz) and healthy young subjects (Meyes-opened = 37.2 Hz, Meyes-closed = 37.0 Hz). These results could be related to AD progression and therefore critical for the recent findings regarding the 40 Hz gamma entrainment because it seems they entrain the gamma frequency of AD towards that of healthy young.
Citation - WoS: 1
Citation - Scopus: 1
Alterations of Store-Operated Calcium Entry and Cyclopiazonic Acid-Induced Endothelium-Derived Relaxations in Aging Rat Thoracic Aorta
(Akademiai Kiado Zrt, 2016) Erac, Y.; Selli, C.; Tosun, Metiner
The purpose of our study was to investigate whether endothelium-derived relaxations induced by store depletion are altered in aging rat thoracic aorta. Vascular responses were measured in aortic segments isolated from young (2-4 month) and old (20-24 month) male Sprague-Dawley rats. In phenylephrine-contracted intact tissues, receptor-mediated and receptor-independent endothelium-derived relaxations were induced by acetylcholine (ACh) and sarcoplasmic/endoplasmic reticulum Ca2+ ATPase (SERCA) blocker cyclopiazonic acid (CPA), respectively. In addition, CPA-induced changes in intracellular calcium levels were monitored in fura-2-loaded endothelium-denuded tissues. Real-time quantitative reverse transcription polymerase chain reaction and western blot analysis were performed to determine the transient receptor potential canonical (TRPC) 4 mRNA and protein levels. Endothelial TRPC4 mRNA levels were apparently decreased in aging rats. Immunoblot analysis showed that TRPC4 protein levels significantly decreased in intact aorta from 20- to 24-month-old rats compared to that from 2- to 4-month-old rats. ACh- and CPA-induced endothelium-dependent relaxations decreased in old rat aorta without any change in direct vasodilation induced by sodium nitroprusside. Store-operated Ca2+ entry (SOCE) induced by CPA was significantly decreased, whereas sarcoplasmic reticulum Ca2+ release was unaffected in endothelium-denuded aging rat aorta. In conclusion, TRPC4 downregulation could be associated with decreased endothelium-dependent vasorelaxations. As endothelial nitric oxide synthase is activated by SOCE-induced caveolar internalization, tracking the expression levels of SERCA, ion channels, and/or associated proteins involved in SOCE would lead to the development of novel therapeutics for age-related vasospastic disorders with dysfunctional endothelium.

Browse

Browsing 01. Araştırma Çıktıları | TR-Dizin | WoS | Scopus | PubMed by WoS Q "Q2"