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Article ISAR Imaging of Drone Swarms at 77 GHz(Tubitak Scientific & Technological Research Council Turkey, 2025) Coruk, Remziye Busra; Kara, Ali; Aydin, ElifThe proliferation of easily available, internet-purchased drones, coupled with the emergence of coordinated drone swarms, poses a significant security threat for airspace. Detecting these swarms is crucial to prevent potential accidents, criminal misuse, and airspace disruptions. This paper proposes a novel inverse synthetic aperture radar (ISAR) imaging technique for high-resolution reconstruction of drone swarms at 77 GHz millimeter wave (mmWave) frequency, offering a valuable tool for military and defense antidrone systems. The key parameters affecting down-range and cross-range resolution (0.05 m), ultimately enabling the generation of detailed ISAR images are discussed. Here, we create diverse scenarios encompassing various swarm formations, sizes, and payload configurations by employing ANSYS simulations. To enhance image quality, different window functions are evaluated, and the Hamming window is selected due to its highest peak signal-to-noise ratio (PSNR) (16.3645) and structural similarity (SSIM) (0.9067) values, ensuring superior noise reduction and structural preservation. The results demonstrate that the effectiveness of high-resolution ISAR imaging in accurately detecting and characterizing drone swarms pave the way for enhanced airspace security measures.Article Citation - WoS: 1Citation - Scopus: 1Solving an initial boundary value problem on the semiinfinite interval(Tubitak Scientific & Technological Research Council Turkey, 2016) Atalan, Ferihe; Guseinov, Gusein Sh.We explore the sign properties of eigenvalues and the basis properties of eigenvectors for a special quadratic matrix polynomial and use the results obtained to solve the corresponding linear system of differential equations on the half line subject to an initial condition at t = 0 and a condition at t = infinity.Article Citation - WoS: 21Citation - Scopus: 23Fear of Missing Out, Internet Addiction and Their Relationship To Psychological Symptoms(Turkish Green Crescent Soc, 2020) Orta, İrem Metin; Metin-Orta, IremInternet addiction has become one of the most important problems of today's youth and received considerableattention from scholars. Research demonstrated significant impairments in psychological and social functioning among internet dependents. Given this, the present study aimed to investigate the relationship betweenfear of missing out (FoMO), internet addiction, and psychological symptoms. Based on research demonstratingthat FoMO, the pervasive anxiety associated with the feeling that one is missing out others’ satisfying experiences, increases social media engagement, it was expected that FoMO would relate to internet addiction, whichin turn would be linked to poor psychological well-being. The sample consisted of 322 undergraduate studentswho filled out items measuring FoMO, internet addiction and psychological symptoms. The regression analysisrevealed that internet addiction acts as a mediator in the link between FoMO and psychological symptoms.That is, the participants’ greater FoMO is linked to higher levels of psychological symptoms both directly andindirectly through a higher level of internet addiction. Overall, the present study provides an insight into ourunderstanding of the psychological and behavioral aspects of internet addiction, and thus, makes an importantcontribution to the promotion of mental health.Article Citation - WoS: 1Citation - Scopus: 1Short-Term Effectiveness of Epidermis Dermis Fascia Kinesiotaping Technique in Myofascial Pain Syndrome on Upper Trapezius: a Multi-Center, Double-Blind, Randomized Clinical Study(Baycinar Medical Publ-Baycinar Tibbi Yayincilik, 2024) Ayhan, Fikriye Figen; Külcü, Duygu Geler; Keleş, Elif Çiğdem; Dinç, Arzu; Mesci, Nilgün; Çakmak, Bahar; Yılmaz, Zeynep Alpoğuz; Erhan, Belgin; Yavas, Arzu Ding; Kölcö, Duygu Geler; Tur, Birkan SonelObjectives: This study aims to investigate the efficacy of epidermis dermis fascia (EDF) kinesiotaping (KT) technique on pain intensity, number of active trigger points (TrPs), cervical range of motion (ROM) angles, and disability levels in patients with myofascial pain syndrome (MPS) on upper trapezius (UT) muscle. Patients and methods: Between January 2019 and January 2020, a total of 180 patients (21 males, 159 females; mean age: 35.9±9.0 years; range, 18 to 56 years) with MPS were included. The patients were randomized into either KT with EDF technique (Group 1) or sham KT (Group 2). Outcome measures were Visual Analog Scale (VAS) pain score, number of active TrPs, cervical ROM angles, and Neck Pain Disability Scale (NPDS). Results: Both groups improved in terms of all outcome parameters except for cervical flexion and extension angles in Group 2. The VAS pain scores significantly decreased in Group 1 (p<0.05), compared to Group 2. The number of active TrPs (p=0.001) and NPDS scores (p=0.016) of Group 1 significantly improved than Group 2. Cervical flexion (p=0.001), extension (p=0.001), and left and right lateral flexion angles (p<0.0001) significantly improved in Group 1. Cervical left (p=0.001) and right (p<0.0001) lateral flexion angles significantly improved in Group 2. There was no significant difference between the groups regarding cervical ROM angles. Conclusion: Our study results suggest that KT with the EDF technique is an effective method in reducing pain and number of active TrPs, improving disability and cervical ROM angles.Article İKİ KATMANLI DOLU BİR SİLİNDİRİN ELASTİK DAVRANIŞININ FARKLI UÇ VE SINIR KOŞULLARI İÇİN ANALİTİK OLARAK İNCELENMESİ(Turkish Soc thermal Sciences Technology, 2020) Akış, Tolga; Eraslan, Ahmet N.İki katmanlı dolu silindirlerin zamana bağlı termoelastik davranışlarının farklı uç ve sınır koşulları için belirlenmesi amacıyla analitik modeller geliştirilmiştir. Söz konusu silindirler, aralarında mükemmel temas olan ikikatmandan oluşmaktadır. Başlangıçta sıcak olan silindir, yüzeyinden konveksiyon yolu ile sıfır derecelik çevreselsıcaklığa veya önceden daha düşük olarak belirlenen yüzey sıcaklığına ulaşana kadar enerji kaybetmektedir. Tümdurumlarda soğuma yavaş bir biçimde gerçekleştiğinden problemde kuplajsız elastisite teorisinin kullanılması mümkünolmuştur. Genelleştirilmiş düzlemsel şekil değiştirme çözümü elde edilmiş ve bu çözüm, eksenel yöndeki birim şekildeğiştirmeyi sıfıra eşitleyerek düzlemsel şekil değiştirme durumuna ait çözüme indirgenmiştir. Bu çözümlere aitsonuçlar, sınır koşullarının serbest olduğu durumlarda radyal ve teğetsel yöndeki gerilmelerin uç koşullarına göredeğişmediğini göstermiştir. Ancak düzlemsel şekil değiştirme durumunda, eksenel gerilme baskın gerilme olmakta veuçların serbest olduğu duruma göre oldukça yüksek değerlere ulaşmaktadır. Kompozit silindirin eksenel ve radyalyönde yer değiştirmesinin kısıtlanması büyük gerilmelere yol açmasına rağmen ilgili gerilme durumu silindirde akmayayol açmamaktadır.Article Citation - WoS: 13Citation - Scopus: 14Evaluation of procedural and clinical outcomes of transcatheter aortic valve implantation: A single-center experience(Kare Publ, 2020) Karaduman, Bilge Duran; Kayaoğlu, Hüseyin Ayhan; Keleş, Telat; Bozkurt, Engin; Ayhan, HuseyinObjective: Transcatheter aortic valve implantation (TAVI) is an established alternative to surgical aortic valve replacement. Our study aimed to evaluate the implementation of TAVI at our large-volume center, having an all-comer patient population with short and long-term follow-ups. Methods: This retrospective, single-center analysis included 556 consecutive patients with symptomatic severe aortic stenosis (AS) who underwent TAVI between July 2011 and December 2019. Results: The mean age of the entire population was 77.6±7.9 years, and 54.9% were women. The Society of Thoracic Surgeons (STS) mean score of the cohort was 6.0%±3.5%. The balloon-expandable valve (Sapien XT, Sapien 3; Edwards Lifesciences, Irvine, California) was the most frequently used valves in this cohort (94.6%). Transfemoral access was used in 96.3% of patients. Implantation success was achieved in 96.6% of cases. During the TAVI procedure, 7.2% of patients required permanent pacemaker implantation, with 37.5% in the Lotus valve group needing the most permanent pacemakers. The mean length of hospital stay for the entire cohort was 4.5±2.3 days. Overall, 22 (3.9%) in-hospital deaths occurred before hospital discharge. The mean follow-up period was 15.1±14.9 months for all patients, and a significant improvement was noted in all echocardiographic parameters and functional capacity. Paravalvular leak (PVL) was documented in 18.9% patients, mild in 17.9%, and moderate in 1% at discharge. No cases with severe PVL, necessitating additional procedures. The multiple logistic regression analysis revealed that sex, STS score, baseline SYNTAX score, bicuspid valve morphology, common femoral artery diameter, and post-TAVI PVL were independent predictors of overall mortality. Conclusion: To our knowledge, this study, which is the largest single-center real-world experience of TAVI in Turkey, demonstrated low complication rates with favorable short- and mid-term THV performance in patients undergoing TAVI.Article Citation - WoS: 2Citation - Scopus: 2Low Carbon Architectural Design(Gazi Univ, 2018) Balku, Saziye; Bal Kocyigit, Filiz; Koçyiğit, Filiz Bal; Architecture; Energy Systems EngineeringTendency towards sustainable energy resources is increasing and leading engineers and architects make joint efforts. Renewable energy potential present in nature can be used more efficiently so that while energy consumption is reducing, rate of energy gain, on the other hand, increases by architectural design methods. A sailing club in Golbasi, Ankara is designed as a low carbon building for optimum usage of solar and wind energy. It can be concluded using an energy efficient architectural design for a building before its construction makes it possible to meet the electrical and heat energy requirements at minimum cost and environmental friendly.Article Citation - WoS: 6Citation - Scopus: 6Covid-19 Infection in Peritoneal Dialysis Patients: \ra Comparative Outcome Study With Patients on \rhemodialysis and Patients Without Kidney Disease(Aves, 2022) Kazancıoğlu, Rümeyza; Ozturk, Savas; Turgutalp, Kenan; Gürsu, Meltem; Arıcı, Mustafa; Oruç, Ayşegül; Ateş, Kenan; Odabas, Ali Riza; Bek, Sibel GökçayObjectives: There is limited data about coronavirus disease-19 (COVID-19) characteristics and results in peritoneal dialysis \r(PD) patients. This study aimed to investigate the characteristics and outcomes among PD patients and compare them with \rmatched hemodialysis (HD) patients and a control group without kidney disease.\rMethods: We included 18 PD patients and consecutive age- and gender-matched 18 HD and 18 patients without kidney \rdisease (control group) registered into the Turkish Society of Nephrology database including 1301 COVID-19 patients. We \rcompared demographic, clinical, radiological, laboratory data, and outcomes namely intensive care unit (ICU) admission, \rmechanical ventilation, mortality, and composite outcome (death and/or ICU admission).\rResults: ICU admission, mechanical ventilation, and mortality rates in PD patients (27.8%, 22.2%, and 22.2%, respectively) \rand the HD group (16.7%, 11.1%, and 16.7%, respectively) were higher than the control group (11.1%, 11.1%, and 5.6%, \rrespectively), but intergroup comparison did not reveal difference. A total of 11 (20.3%) patients had composite outcome \r(6 PD patients, 3 HD patients, and 2 patients in the control group). In Cox regression analysis, higher age and higher CRP level were related to increased risk of composite outcome. Adjusted rate of composite outcome in PD group was significantly higher than \rthe control group (P = .050). This rate was similar in HD and control groups (P = .30).\rConclusions: Combined in-hospital mortality and/or ICU admission of PD patients with COVID-19 was significantly higher than the control \rpatients. There is a need for careful surveillance of PD patients for infection signs and prompt treatment of COVID-19.Article Citation - WoS: 8Citation - Scopus: 10Nöromüsküler Hastalarda Gövde Kontrolünün Değerlendirilmesi: Gövde Bozukluk Ölçeği’nin Geçerlik ve Güvenirliği(Turkish Neurological Soc, 2018) Demir, Yasemin Parlak; Yıldırım, Sibel AksuAmaç: Çalışmamızın amacı Gövde Bozukluk Ölçeği’nin (GBÖ) erişkin nöromüsküler hastalıklarda geçerlik ve güvenirliğini araştırmaktır. Gereç ve Yöntem: Çalışmaya 66 nöromüsküler hastalık tanısı olan birey alındı. Çalışmaya dahil edilen olgulara GBÖ, Manuel Kas Testi (gövde, üst ve alt ekstremite), Motor Fonksiyon Değerlendirme Ölçeği (MFM), Fonksiyonel Bağımsızlık Ölçeği (FIM), Rivermead Mobilite İndeksi (RMI) yapıldı. Bulgular: GBÖ’nün test tekrar test, ICC güvenirlikleri mükemmel bulundu (GBÖ: 0,96 ve 0,98). Cronbach alfa katsayısı 0,82 bulundu. Yapı geçerliği için GBÖ ile MFM (r=0,29), MFM gövde (r=0,31), toplam gövde kas kuvveti (r=0,34), toplam alt ekstremite kas kuvveti (r=0,34, p<0,05), toplam kas kuvveti (gövde, alt ve üst ekstremite) (r=0,52, p<0,05) arasında anlamlı ilişki bulundu. GBÖ uyum geçerliği için FIM (r=0,32, p<0,05) ve RMI (r=0,39, p<0,05) ile ilişkili bulundu. Sonuç: Çalışmanın sonucunda GBÖ’nün erişkin kas hastalıklarında yapı ve uyum geçerliliğinin olduğu ve mükemmel güvenirliğe sahip olduğu bulundu. GBÖ rehabilitasyon kliniklerinde uygulaması kolay ve kısa zaman alan bir ölçektirArticle Citation - WoS: 1Citation - Scopus: 1On Some Permutation Trinomials in Characteristic Three(Hacettepe Univ, Fac Sci, 2025) Temür, Burcu Gülmez; Özkaya, Buket; Gülmez Temür, BurcuIn this paper, we determine the permutation properties of the polynomial x3 +xq+2 −x4q−1 over the finite field Fq2 in characteristic three. Moreover, we consider the trinomials of the form x4q−1 + x2q+1 ± x3. In particular, we first show that x3 + xq+2 − x4q−1 permutes Fq2 with q = 3m if and only if m is odd. This enables us to show that the sufficient condition in [34, Theorem 4] is also necessary. Next, we prove that x4q−1 + x2q+1 − x3 permutes Fq2 with q = 3m if and only if m ̸≡ 0 (mod 4). Consequently, we prove that the sufficient condition in [20, Theorem 3.2] is also necessary. Finally, we investigate the trinomial x4q−1 + x2q+1 + x3 and show that it is never a permutation polynomial of Fq2 in any characteristic. All the polynomials considered in this work are not quasi-multiplicative equivalent to any known class of permutation trinomials.
