Browsing by Author "Sari A."

Now showing 1 - 9 of 9
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    A proposed artificial neural network model for PEM fuel cells
    (IEEE Computer Society, 2013) Sari A.; Balikci A.; Taskin S.; Aydin S.
    Fuel cells convert the chemical energy directly to the electrical energy and hence they are a very favorable alternative energy source. In the literature, there are many studies related to the modeling of fuel cells. Artificial neural networks (ANNs) is one of the promising techniques for modelling nonlinear systems such as fuel cells. The proposed model in this study doesn't require many parameters like other studies. Firstly, training and testing data was obtained the dynamic model of a PEM fuel-cell. Then, proposed ANN model outputs are compared with dynamic model ouputs Simulation results shows that the proposed ANN model can be used very efficiently for PEM fuel-cells without using many parameters. © 2013 The Chamber of Turkish Electrical Engineers-Bursa.
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    Vibration modelling of piezoelectric actuator (PEA) using Simulink software
    (Institute of Electrical and Electronics Engineers Inc., 2017) Parali L.; Sari A.
    This paper presents to define a vibration modelling of a PEA using MATLAB-Simulink software based on a single degree freedom mechanical model. The experimental vibration displacement values of PEA have been carried out utilizing the swept-sine signal excitation following the peak values in the signal response measured as contactless by the laser displacement sensor. Harmony between the mathematical modelling and experimental values have been observed from 96.6 to 81.4 % between excitation amplitudes of 0.5 and 3.0 V when the vibration modelling of PEA is normally taken into consideration with a linear working range. Therefore, obtained this vibration modelling could be used as training-testing tool for estimating vibration characterization of an actuator under any excitation voltages. © 2017 IEEE.
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    Estimating elasticity modulus of the piezo ceramic disc (PCD) using basic mathematical modelling
    (Elsevier GmbH, 2018) Parali L.; Sari A.; Malgaca L.; Pechousek J.; Latal F.
    The objective of this paper is to determine a mathematical modelling of piezoceramic disc vibration using a single degree freedom mechanical model, with estimation of its elasticity modulus. The experimental vibration displacement values of piezo ceramic disc have been achieved utilizing the swept-sine signal excitation following the peak values in the signal response measured by the laser Doppler vibrometer. Consistency between the mathematical modelling and experimental values have been observed from 97 to 80% between excitation amplitudes of 0.5 and 3.5 V when the mathematical modeling of piezo ceramic disc is normally taken into consideration with a linear working range. The results obtained from experimental studies on resonance frequency are in a compliance with reference value declared by producer of the piezo ceramic disc. © 2018 Elsevier GmbH
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    Comparative evaluation of PVDF based piezoelectric nanogenerator (PNG) under various resistive loads for energy harvesting applications
    (Institute of Electrical and Electronics Engineers Inc., 2020) Parali L.; Koc M.; Sari A.
    Piezoelectric nanogenerator (PNG) is a type of sensor that converts mechanical energy to electrical energy by detecting small-scale physical deformation. In this study, to realize a PNG, firstly polyvinylidene difluoride (PVDF) based electrospun nanofiber film is produced through electrospinning system. The obtained nanofiber film was characterized by X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM), and Fourier Transform Infrared spectroscopy (FTIR). After that, the PNG device was built as the capacitor by locating the PVDF electrospun nanofiber between two aluminum conductive plates and cabled. The piezoelectric energy harvesting analyses of the PNG was defined by taking measurements under various resistive loads. At a vibration frequency of 15 Hz, the effective voltage value of the PNG reached the maximum voltage of 62.6 mV under the resistive load of 750 KΩ while its electrical power was around 5.23 μ W under the same load. The PNG based energy harvesting system aims to obtain electrical energy from the natural vibrational sources for mobile microelectronics. © 2020 IEEE.
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    Best Practice Recommendations for Stroke Patients with Dysphagia: A Delphi-Based Consensus Study of Experts in Turkey-Part II: Rehabilitation
    (Springer, 2021) Umay E.; Eyigor S.; Ertekin C.; Unlu Z.; Selcuk B.; Bahat G.; Karahan A.Y.; Secil Y.; Gurcay E.; Kıylioglu N.; Keles B.Y.; Giray E.; Tikiz C.; Gezer I.A.; Yalıman A.; Sen E.I.; Vural M.; Saylam G.; Akaltun M.S.; Sari A.; Alicura S.; Karaahmet F.; Inanir M.; Demirhan A.; Aydeniz B.; Bilgilisoy M.; Yuksel A.; Ozcete Z.A.; Calik Y.; Alemdaroglu E.; Keskin D.; Sahin S.; Oztekin M.F.; Sezgin B.; Karaahmet O.
    Dysphagia is one of the most common and important complications of stroke. It is an independent marker of poor outcome following acute stroke and it continues to be effective for many years. This consensus-based guideline is not only a good address to clinical questions in practice for the clinical management of dysphagia including management, diagnosis, follow-up, and rehabilitation methods, but also includes detailed algorithms for these topics. The recommendation paper has been written by a multidisciplinary team and offers 117 recommendations for stroke patients with dysphagia. While focusing on management principles, diagnosis, and follow-up in the 1st part (45 items), rehabilitation details were evaluated in the 2nd part (72 items). © 2021, Springer Science+Business Media, LLC, part of Springer Nature.
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    Best Practice Recommendations for Geriatric Dysphagia Management with 5 Ws and 1H
    (Korean Geriatrics Society, 2022) Umay E.; Eyigor S.; Bahat G.; Halil M.; Giray E.; Unsal P.; Unlu Z.; Tikiz C.; Vural M.; Cincin A.T.; Bengisu S.; Gurcay E.; Keseroglu K.; Aydeniz B.; Karaca E.C.; Karaca B.; Yalcin A.; Ozsurekci C.; Seyidoglu D.; Yilmaz O.; Alicura S.; Tokgoz S.; Selcuk B.; Sen E.I.; Karahan A.Y.; Yaliman A.; Ozkok S.; Ilhan B.; Oytun M.G.; Ozturk Z.A.; Akin S.; Yavuz B.; Akaltun M.S.; Sari A.; Inanir M.; Bilgilisoy M.; Çaliskan Z.; Saylam G.; Ozer T.; Eren Y.; Bicakli D.H.; Keskin D.; Ulger Z.; Demirhan A.; Calik Y.; Saka B.; Yigman Z.A.; Ozturk E.A.
    Background: Dysphagia is a geriatric syndrome. Changes in the whole body that occur with aging also affect swallowing functions and cause presbyphagia. This condition may progress to oro-pharyngeal and/or esophageal dysphagia in the presence of secondary causes that increase in incidence with aging. However, no study has been published that provides recommendations for use in clinical practice that addresses in detail all aspects of the management of dysphagia in geriatric individuals. This study aimed to answer almost all potential questions and problems in the management of geriatric dysphagia in clinical practice. Methods: A multidisciplinary team created this recommendation guide using the seven-step and three-round modified Delphi method via e-mail. The study included 39 experts from 29 centers in 14 cities. Results: Based on the 5W and 1H method, we developed 216 detailed recommendations for older adults from the per-spective of different disciplines dealing with older people. Conclusion: This consensus-based recommendation is a useful guide to address practical clinical questions in the diagnosis, rehabilita-tion, and follow-up for the management of geriatric dysphagia and also contains detailed com-mentary on these issues. © 2022 by The Korean Geriatrics Society.
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    Best Practice Recommendations for Stroke Patients with Dysphagia: A Delphi-Based Consensus Study of Experts in Turkey-Part I: Management, Diagnosis, and Follow-up
    (Springer, 2022) Umay E.; Eyigor S.; Ertekin C.; Unlu Z.; Selcuk B.; Bahat G.; Karahan A.Y.; Secil Y.; Gurcay E.; Kıylioglu N.; Yavuz Keles B.; Giray E.; Tikiz C.; Albayrak Gezer I.; Yalıman A.; Sen E.I.; Vural M.; Saylam G.; Akaltun M.S.; Sari A.; Alicura S.; Karaahmet F.; Inanir M.; Demirhan A.; Aydeniz B.; Bilgilisoy M.; Yuksel A.; Ozcete Z.A.; Calik Y.; Alemdaroglu E.; Keskin D.; Sahin S.; Oztekin M.F.; Sezgin B.; Karaahmet O.; Bengisu S.; Yalcin Gokler T.; Mercimekci S.
    Dysphagia is one of the most common and important complications of stroke. It is an independent marker of poor outcome after acute stroke and may become chronic after the acute period and continues to affect all aspects of the patient's life. Patients with stroke may encounter any of the medical branches in the emergency room or outpatient clinic, and as in our country, there may not be specialists specific for dysphagia, such as speech-language pathologists (SLP), in every hospital. This study aimed to raise awareness and create a common opinion of medical specialists for stroke patients with dysphagia. This recommendation paper has been written by a multidisciplinary team and offers 45 recommendations for stroke patients with dysphagia. It was created using the eight-step Delphi round via e-mail. This study is mostly specific to Turkey. However, since it contains detailed recommendations from the perspective of various disciplines associated with stroke, this consensus-based recommendation paper is not only a useful guide to address clinical questions in practice for the clinical management of dysphagia in terms of management, diagnosis, and follow-up, but also includes detailed comments for these topics. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
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    Clinical and Demographic Characteristics of Treatment Requiring Retinopathy of Prematurity in Big Premature Infants in Turkiye: Report No. 1 (BIG-ROP Study)
    (S. Karger AG, 2024) Özdek Å.; Ozdemir H.B.; Ozen Tunay Z.; Bayramoglu S.E.; Alyamac Sukgen E.; Klr N.; Koç E.; Ekinci D.Y.; Sayin N.; Ceylan N.A.; Cebeci Z.; Çelik G.; Kizilay O.; Demir S.T.; Yildiz M.; Öztürk T.; Bekmez S.; Eris E.; Çömez A.; Mayali H.; Kabatas E.U.; Satirtav G.; Ögreden T.; Vural A.; Onur I.U.; Yeter D.Y.; Gönc T.; Tanidir S.T.; Akdogan M.; Çelemler P.; Beyazyildiz E.; Beyazyildiz Ö.; Acar D.E.; Özbay E.K.; Özcan Y.; Keles S.; Yildirim M.; Uzun A.; Dikci S.; Sari A.; Kara C.; Petriçli I.S.; Comba Ö.B.S.; Albayrak S.; Ersan B.A.; Bilgin B.; Çeliker H.; Sahin O.; Seymen Z.; Alaluf A.; Kaymak N.Z.; Oral A.Y.; Kerimoglu H.; Ünsal A.I.A.; Hirfanoglu I.M.; Tayman C.; Mert M.K.; Çetinkaya M.; Karatekin G.; Uslu S.; Özkan H.; Tüzün F.; Yildirim T.G.; Yurttutan S.; Dinlen N.F.; Bezirganoglu H.; Altinhan H.; Salihoglu Ö.; Tun G.; Karakurt D.G.; Bas A.Y.; Demiroglu Ö.B.; Aygün C.; Tekgündüz K.S.; Ceylan M.; Özdemir R.; Zübahiroglu U.; Özkiraz S.; Cömert S.; Akcan A.B.
    Introduction: The aim of the study was to analyse the clinical and demographic features of infants with gestational age (GA) of 32-37 weeks and birth weight (BW) of >1,500 g who developed treatment requiring retinopathy of prematurity (ROP). Methods: Data on the infants with a GA of 32-37 weeks and BW >1,500 g who developed treatment requiring ROP (TR-ROP) were collected retrospectively from the 33 ROP centres in Turkiye. GA, BW, type of hospital, neonatal intensive care units (NICUs) level, presence of an ophthalmologist and neonatologist in the same hospital, length of stay in NICU, duration of oxygen therapy, comorbidities, type of ROP, and timing for TR-ROP development were analysed. Results: A total of366 infants were included in the study. Mean GA and BW were 33 1 weeks and 1,896 316 g, respectively. Duration of hospitalization was 3-4 weeks in 46.8% of them. The first ROP examination was performed at postnatal 4-5 weeks in 80.3% of infants, which was significantly later in level 2 and lower NICUs and non-university clinics. At the first ROP examination, any stage of ROP was detected in 90.9% and TR-ROP was detected in 15.3% of the infants. The mean postnatal week of TR-ROP development was 6.16 2.04. Conclusion: Routine ROP screening thresholds need to be expanded in hospitals with suboptimal NICU conditions considering the development of TRROP in more mature and heavier preterm infants. The first ROP examination should be earlier than the fourth postnatal week. 2024 S. Karger AG, Basel. © 2024 S. Karger AG. All rights reserved.
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    Phase change material incorporated paper pulp sludge/gypsum composite reinforced by slag and fly ash for energy efficient buildings: Solar thermal regulation, embody energy, sustainability index and cost analysis
    (Elsevier Ltd, 2024) Kucukdogan N.; Sutcu M.; Ozturk S.; Yaprak H.; Memis S.; Gencel O.; Ustaoglu A.; Sari A.; Hekimoglu G.; Erdogmus E.
    This study focuses on the reuse of some industrial wastes in the development of innovative building materials and the thermal performance, environmental impacts and cost estimates of the gypsum composite material developed in the case of a phase change material impregnation. Lauryl alcohol (LA) was impregnated into paper pulp sludge (PPS) up to 45 % by weight without leakage to obtain shape-stable composites. The LA impregnated PPS (PPS/LA) was replaced with PPS at 50 % and 100 % by weight in gypsum composite. Characteristics of shape-stable composites were studied. Also, the physical, mechanical, thermal properties and solar thermoregulation tests of the produced gypsum composites were examined in addition to the embodied energy, CO2 emissions and cost analysis. The melting and solidification enthalpies of PPS/LA were found to be 100.4–100.1 J/g, with only a 0.5 % reduction in latent heat storage capacity after 500 cycles, and approximately 3 % after 1500 cycles. Although the presence of PPS/LA in the gypsum composite caused a slight decrease in compressive strength, it significantly improved solar thermoregulation performance, maintaining ambient temperatures 2.55 °C to 5 °C warmer at night and 5.3 °C to 13.8 °C cooler during the day. Gypsum composites containing the PPS/LA offer a suitable alternative for energy-efficient sustainable building application by reusing around 57 % of three different industrial wastes providing a waste-reducing environmental approach and a high level of indoor thermal comfort. © 2024