Fakülteler / Faculties
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Item Low Velocity Bird-Like Impact Behavior on Honeycomb Composite Structure(Başkent Üniversitesi Mühendislik Fakültesi, 2024-07-20) Ozturk, Okan; Elaldi, FarukComposite materials are widely used in primary aerospace structures such as wing components and fuselage panels; however, their major disadvantage is their vulnerability to transverse impact loads that can lead to internal delamination and fiber/matrix separation. In this study, the effect of a low-velocity impact which simulates bird impact on a honeycomb sandwich composite plates produced by a co-curing technique for a typical unmanned air vehicle (UAV) was studied both experimentally and numerically. The surface plates of the composite samples were produced from carbon fiber/epoxy prepreg material. Nomex honeycomb core material was used to make the composite sandwich structure via an autoclave process. For the bird-like impact test, the tip of the impactor was coated with thick, tough rubber to simulate a bird strike; the diameter of the impactor was 25 mm to ensure similarity with a bird called Pica nuttalli (magpie), which has a mass of 155 g and is the closest bird body to the simulations. Three different predetermined impact scenarios with kinetic energy 380 Joule, 276 Joule, and 224 Joule were applied to the samples with rubber impactors of similar density, to simulate bird impact events with different impact directions. The impact behavior was characterized by velocity-time, force-time, and displacement-time graphs. Different levels of damage were observed in the composite samples, but none of the sandwich test samples were perforated, and it could therefore be concluded that the unmanned air vehicle could land without risk to flight safety. Ultrasound, digital microscope, and tap inspections have been applied for test samples to determine damage area size and types. This low-velocity bird-like impact was also modeled and analyzed using Ansys numerical program to verify the results, and it was concluded that the verified model could also be used for the preliminary design verification of dynamic bird-impact tests within the 10% sensitivity range.Item The Acute Effects of Kinesio Taping on Drooling in Children with Cerebral Palsy: A Randomized Placebo-Controlled Trial(Başkent Üniversitesi Sağlık Bilimleri Fakültesi, 2024-07-14) Yilmaz, Nilsah; Turker, Duygu; Aytar, Ayca; Yemisci, Oya Umit; Aytar, AydanIntroduction: This study purpose of determining the short-term effects of kinesio taping on drooling in children with cerebral palsy (CP). Methods: CP were randomly divided into 3 groups as the kinesio tape (n = 16), sham tape (n = 16), and control (n = 16) groups. The drooling severity and frequency were assessed with the Drooling Severity and Frequency Scale, and the amount of saliva was measured by the 5-minute drooling quotient. All outcome measurements were repeated for all children at the baseline, after 45 minutes, and after 2 days of application. Results: There was a significant decrease found in drooling severity, frequency, and amount in the kinesio taping group (p < .05). There was no significant difference in the sham taping and control groups (p > .05). Conclusion: The use of kinesio tape in drooling reduced drooling severity, frequency, and amount.Item Mentalizing Self Mind But Not Others: Self-Reported Mentalization Difficulties In Multiple Sclerosis(Başkent Üniversitesi Fen Edebiyat Fakültesi, 2024-07-05) Kumcu, Muge Kuzu; Kaya, Zulal Torenli; Alici, Yasemin HosgorenBackgroundMentalization can be defined as a mental process by which an individual directly or indirectly perceives and interprets one's own and others' behavior, emotions, beliefs, and needs based on designed mental states. Mentalization problems may be linked to remove associative white matter fiber disconnection. Multiple sclerosis (MS) is one of the diseases with white matter lesions. By comparing MS patients with healthy controls, it was aimed to assess whether MS patients' mentalization skills are affected.MethodThis study involved 243 participants (170 healthy controls and 73 patients with MS). All the participants completed a sociodemographic questionnaire and the Mentalization Scale (MentS).ResultsWhile it was discovered that MentS scores for the dimension of others-based mentalization (MentS-O) were statistically lower in MS group, there was no statistically significant difference between the groups in terms of the dimensions of motivation to mentalize (MentS-M) and self-based mentalization (MentS-S) scores.ConclusionWe may conclude that MS patients have trouble comprehending other people's thoughts. This effect can be one of the causes of MS patients' issues with social cognition.Item The Role Of Parents' Attitudes Towards Children's Use Of Communication Technologies And School Climate In Coping With Cyberbullying Among High School Students In Turkey(Başkent Üniversitesi Sağlık Bilimleri Fakültesi, 2024-07-04) Yilmaz, Beyza; Aydogan, Selin Nur; Kocyigit, ElifIn this study, cyberbullying is discussed through the school-family-child triangle. The research was conducted to examine how high school students' coping levels with cyberbullying are affected by the school climate and their parents' attitudes towards children's use of information and communication technologies. The research, which was conducted with both parents and students, was carried out with a quantitative method, survey model, and relational design. The data collection tool prepared for students consists of the sociodemographic information questionnaire, the Coping with Cyberbullying Scale and the School Climate Scale. The data collection tool prepared for parents consists of the sociodemographic information questionnaire and the Parents' Attitudes Towards Children's Use of Information Communication Technologies Scale. Four hundred fifty students in the 9-11th grades and 203 parents studying in two public high schools in & Ccedil;ankaya district of Ankara province were reached. The answers given by the students and their parents to the questionnaires were analysed separately and by matching the parent and student questionnaires of the students whose parents also filled out the questionnaire. Of the students, 82.4% had encountered cyberbullying. Girls have higher coping skills with cyberbullying than boys (p < 0.05). Parents' control and restrictions on their children's technology use were found to be high.Item The Effects Of Aromatherapy Massage In Menopausal Women With Knee Osteoarthritis: A Randomized Controlled Study(Başkent Üniversitesi Sağlık Bilimleri Fakültesi, 2024-07-16) Doner, Serife Irem; Gercek, Hasan; Sert, Ozlem Akkoyun; Aytar, Ayca; Aytar, AydanObjective: Knee Osteoarthritis (OA)'s prevalence increases during menopause. Aromatherapy massage with different oils is applied in the treatment of knee OA. The aim of this study was to determine the effects of aromatherapy massage with Bergamot essential oil (BEO) on pain, functionality, sleep quality and menopausal symptoms in menopausal women with knee OA. Materials and methods: This study included 60 menopausal participants diagnosed with grade II-III OA. Participants were randomly divided into three groups: BEO (n=20), placebo (n=20) and control (n=20). The participants in the BEO group, received aromatherapy massage with BEO, in the placebo group aromatherapy massage with sweet almond oil was applied twice a week for 4 weeks. All participants underwent conventional physiotherapy. Visual Analog Scale was used to assess the severity of pain, Osteoarthritis Index to assess functionality, Pittsburgh Sleep Quality Index to assess sleep quality and Menopausal Symptoms Rating Scale to assess menopausal symptoms. All measurements were performed before and after the study. Results: The results of the study showed that all three groups were effective on pain, functionality, sleep quality and menopausal symptoms (p<0.001). The results of the study showed that, aromatherapy massage with BEO was found to be more effective on functionality (p<0.001), pain (p<0.001) and menopausal symptoms (somatic and psychological symptoms) (p<0.001) compared to the control and placebo groups. It was determined that aromatherapy massage with BEO did not create a significant difference between the sleep quality scale scores in the control group and the placebo group (p=0.454). Conclusion: This study found that aromatherapy massage with BEO improved functionality, reduced pain and menopausal symptoms, and did not affect sleep quality. We consider that its application in addition to routine treatment may be useful to reduce symptoms.Item Comment On: Prevalence Of Acute Periapical Abscesses In Head And Neck Cancer Patients Receiving Radiotherapy(Başkent Üniversitesi Diş Hekimliği Fakültesi, 2024-07-01) Somay, Efsun; Topkan, Erkan; Selek, UgurItem Evaluation Of Maxillary Dimensional Changes In The Mixed Dentition: Clear Aligners Vs Acrylic Expanders(Başkent Üniversitesi Diş Hekimliği Fakültesi, 2024-07-10) Pamukcu, Hande; Ozsoy, Serhat; Aksoy, Polat Can; Ozsoy, Omur PolatObjectives: To compare changes in upper arch dimension and molar inclination between Invisalign First (IF) and removable acrylic expander (RE) treatments during the mixed dentition period. Materials and Methods: Seventeen patients meeting inclusion criteria underwent IF treatment and were age matched with a group that received treatment with a removable acrylic expander (RE). Intercanine width (ICW), intermolar width, arch depth, buccolingual inclination of the first molars (MI), surface area (SA) and volume (VAP) of the anterior palate, and expansion were compared before and after treatment. The predictability of expansion was calculated for the IF group. Analysis of variance and Kruskal-Wallis tests were used to assess differences. Results: The ICW increased significantly by 2.14 mm in the IF group and 3.49 mm in the RE group, with no significant intergroup difference. Both groups exhibited significant increases in intermolar width (P < .05), except for intermolar distopalatal width in the IF group (P 1/4 .246). Mesiobuccal rotation of the first molar was observed with IF treatment. Although SA and VAP increased in both groups, the changes were not significant for the IF group (P . .05). The RE group exhibited significantly higher increases (P < .05), with an SA increase of 34.32 mm2 and VAP increase of 119.15 mm3. MI changes were in the opposite directions. The prediction accuracy of expansion was 70.28% for canines and 34.12% for first molars. Conclusions: Both appliances effectively expanded the intercanine region in growing patients. Expansion predictability was lower in first molars than in canines for the IF group. Removable acrylic expanders could be a choice of preference for expansion targeted to the molar region. (Angle Orthod. 2024;94:392-399.)Item Seismic Assessment of Electrical Equipment in Power Substations: A Case Study for Circuit Breakers(Başkent Üniversitesi Mühendislik Fakültesi, 2024-07-18) Kaatsiz, Kaan; Alici, Firat Soner; Erberik, Murat AltugElectric power is essential in post-earthquake periods for the continuous functionality of disaster management and emergency services. In addition, interruption of electric power can cause significant economic losses due to downtime of critical facilities. Therefore, it is very important to maintain seismic safety of electric power systems and components. There are existing seismic regulations and standards regarding electric power systems, especially in the United States of America (USA) and Europe. A similar regulation has been prepared recently in T & uuml;rkiye, which is a country in a seismically active region. This study focuses on the current state of practice regarding the seismic assessment of electrical equipment in power stations and implementation of the regulations on seismic qualification of these systems. Among many electrical equipment, circuit breakers have been selected for case study. The seismic assessment of the selected high voltage equipment has been performed according to the new regulation under the seismic hazard specifically defined for T & uuml;rkiye. The case study experiment presents the new methodology in evaluating and classifying the seismic response of high voltage electrical equipment and provides insight to the expected behaviour of circuit breakers under earthquake induced action.Item Comment on: Prevalence of acute periapical abscesses in head and neck cancer patients receiving radiotherapy(Başkent Üniversitesi Diş Hekimliği Fakültesi, 2024-07-01) Somay, Efsun; Topkan, Erkan; Selek, UgurItem Observational Test Of R 2 Spacetimes With The S2 Star In The Milky Way Galactic Center(Başkent Üniversitesi Mühendislik Fakültesi, 2024-08-06) Yan, Jian-Ming; Zhu, Tao; Azreg-Ainou, Mustapha; Jamil, Mubasher; Nguyen, Hoang KyA novel class of vacuum metrics expressible in analytical form was recently found for pure 7Z2 2 gravity, based on a groundwork put forth by Buchdahl in 1962. These Buchdahl-inspired solutions offer a practical framework for testing 7Z2 2 gravity through empirical observations. Within a subclass of asymptotically flat Buchdahl-inspired vacuum spacetimes, we identified a parameter E measuring the deviation from the classic Schwarzschild metric, which corresponds to E = 0. In this paper, we employ observational data from the S2 star's orbit around Sgr A* in the Milky Way galactic center and perform Monte Carlo Markov Chain simulations to probe the effects of the new metrics on the orbit of the S2 star. Our analysis presented herein reports a range at 95% confidence level on the deviation parameter as E is an element of (-0.6690, - 0.6690, 0.4452). While no decisive evidence either in favor or in disfavor of the asymptotically flat Buchdahl-inspired spacetimes has been achieved, the obtained bound is compatible with the tighter results using other data of different nature as recently reported in Eur. Phys. J. C 84 (2024) 330. As a meaningful test probing into a strong-field regime, our present study calls for further observations with prolonged period and improved accuracy in order to tighten the bound for E using the S2 star orbit.