Atılım Academic Archive (Atılım University)
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Impact of Green Wall and Roof Applications on Energy Consumption and Thermal Comfort for Climate Resilient Buildings
No full textOzbey, Mehmet Furkan/0000-0002-5813-3514Nowadays, reducing energy consumption and obtaining thermal comfort are significant for making educational buildings more climate resilient, more sustainable, and more comfortable. To achieve these goals, a sustainable passive method is that of applying green walls and roofs that provide extra thermal insulation, evaporative cooling, a shadowing effect, and the blockage of wind on buildings. Therefore, the objective of this study is to evaluate the impact of green wall and roof applications on energy consumption and thermal comfort in an educational building. For this purpose, a university building in the Csb climate zone is selected and monitored during one year, as a case study. Then, the case building is modelled in a well-calibrated dynamic building energy simulation tool and twenty-one different plant species, which are mostly used for green walls and roofs, are applied to the envelope of the building in order to determine a reduction in energy consumption and an increase in thermal comfort. The Hedera canariensis gomera (an ivy species) plant is used for green walls due to its aesthetic appeal, versatility, and functional benefits while twenty-one different plants including Ophiopogon japonicus (Mando-Grass), Phyllanthus bourgeoisii (Waterfall Plant), and Phoenix roebelenii (Phoenix Palm) are simulated for the green roof applications. The results show that deploying Hedera canariensis gomera to the walls and Phyllanthus bourgeoisii to the roof could simultaneously reduce the energy consumption by 9.31% and increase thermal comfort by 23.55% in the case building. The authors acknowledge that this study is solely based on simulations due to the high cost of all scenarios, and there are inherent differences between simulated and real-world conditions. Therefore, the future work will be analysing scenarios in real life. Considering the limited studies on the effect of different plant species on energy performance and comfort, this study also contributes to sustainable building design strategies.Atilim University-Undergraduate Research Projects [ATU-LAP-2021-11]This study is funded by Atilim University-Undergraduate Research Projects with a grant number of ATU-LAP-2021-11.Emerging Sources Citation Inde
The Relationship Between Soong Classification and Fracture Characteristics with Implant Removal for Distal Radius Fractures: A Comparative Study of 795 Cases
No full textYogun, Yener/0000-0002-3070-5509; Gezer, Mehmet Can/0000-0001-7034-2522;Introduction: Although there is no consensus in the literature, it is believed that the Soong classification system and fracture pattern are risk factors for plate removal in distal radius fractures. Hypothesis: The aim of this large-scale study was to evaluate the relationship between Soong classification, fracture pattern, and implant removal in distal radius fractures. Materials and methods: We retrospectively evaluated 795 patients who underwent surgery using a volar locking plate for distal radius fractures at our clinic between 2005 and 2022. The patients were divided into two groups: implant removed, and implant retained. The groups were examined for demographic data, follow-up periods, fracture classifications, and radiological parameters. Additionally, the patients were divided into groups and compared according to the Soong classification, which was determined according to implant placement. Indications for implant removal were also included in this study, and their relationships with other parameters were evaluated. Results: A total of 123 and 672 patients were included in the implant removed and retained groups, respectively. The average age of the implant removed group was significantly lower (p = 0.005). There were no significant differences between the two groups in terms of fracture classification or other radiological parameters. In the implant removed group, the rate of grade 2, according to the Soong classification, was statistically higher than that in the other groups (p = 0.019). Flexor tenosynovitis was the most common reason for implant removal. Conclusion: The Soong classification system is an important risk factor associated with implant removal. This risk may increase, particularly among young patients. Surgeons should consider placing the distal radius locking plate as proximally as possible to reduce the frequency of implant removal. Level of evidence: III; retrospective comparative stud
Key Drivers and Barriers Influencing the Adoption of 3D Printing Technology in the Turkish Construction Industry
No full textBu çalışmada, Türk inşaat sektöründe 3B baskı teknolojisinin benimsenmesini etkileyen temel faktörler incelenmiştir. Bu doğrultuda, kapsamlı bir literatür taraması sonucunda 27 teşvik edici ve 19 engelleyici faktör belirlenmiş olup, bu faktörlerin değerlendirmesi 106 uzmandan oluşan bir anket çalışması ile yapılmıştır. Bu faktörlerin önemi, Göreceli Önem İndeksi (GÖİ) kullanılarak değerlendirilmiş ve ardından Analitik Hiyerarşi Prosesi (AHP) ile faktörlerin önem düzeyleri belirlenmiştir. 3B baskı teknolojisinin daha hızlı inşaat, iş kazalarının azalması, enerji verimliliğinin artması ve karmaşık tasarımların daha kolay uygulanması gibi avantajlar sunduğu görülse de, bu teknolojinin benimsenmesini engelleyen başlıca zorluklar arasında 3B Beton Baskı için yeterli düzenlemelerin ve yapı kodlarının eksikliği, büyük ölçekli uygulamalar konusunda sınırlı bilgi ve yalıtım malzemelerinin yetersizliği yer almaktadır. Araştırma sonuçları, malzeme israfını azaltma ve daha fazla özelleştirme imkânı sağlama gibi faktörlerin 3B baskının inşaat sektöründe benimsenmesinde en önemli etmen olduğunu, gözetim maliyetlerinin azaltılmasının ise en az önemli teşvik edici faktör olduğunu ortaya koymuştur. Diğer yandan, siber güvenlik riskleri, potansiyel iş kayıpları ve basılı yapıların katmanlı ve pürüzlü yüzeyleri, en kritik engeller olarak belirlenmiştir. Bu araştırma, 3B baskı teknolojisinin inşaat sektörüne entegrasyonunun artırılması için bu etmenlerin ve engellerin hedefe yönelik stratejilerle ele alınması gerektiğini vurgulamaktadır.This study explores the key factors influencing the adoption of 3D printing technology in the construction industry, with a focus on Türkiye. An extensive literature review was conducted to identify 27 drivers and 19 barriers, which were subsequently evaluated through a survey of 106 industry experts. The significance of these factors was assessed using the Relative Importance Index (RII), and further analyzed with the Analytic Hierarchy Process (AHP) to prioritize and determine their relative importance. It is discovered that although 3D printing offers benefits such as faster construction, reduced site accidents, improved energy efficiency, and ease in implementing complex designs, its adoption is hindered by challenges including the lack of regulations and building codes for 3D Concrete Printing (3DCP), limited knowledge of large-scale applications, and insufficient availability of insulating materials. The results highlight that reducing material waste and enabling greater customization are the most significant drivers for adopting 3D printing in construction, while the reduction in supervision costs was the least important. Conversely, cybersecurity risks, potential job losses, and the layered and rough surface of printed structures were identified as the most critical barriers. This research underscores the need to address these drivers and barriers through targeted strategies to enhance the integration of 3D printing technology in the construction industry
On Some Permutation Trinomials in Characteristic Three
No full textIn 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
Calcium Phosphate Honeycomb Scaffolds With Tailored Microporous Walls Using Phase Separation-Assisted Digital Light Processing
No full textThe present study reports on the manufacturing of biphasic calcium phosphate (BCP) honeycomb scaffolds with tailored microporous walls using phase separation-assisted digital light processing (PS-DLP). To create micropores in BCP walls, camphene was used as the pore-forming agent for preparing BCP suspensions, since it could be completely dissolved in photopolymerizable monomers composed of triethylene glycol dimethacrylate (TEGDMA) and polyethylene glycol diacrylate (PEGDA) and then undergo phase separation when placed at 5 degrees C. Therefore, solid camphene crystals could be formed in phase-separated BCP layers and then readily removed via sublimation after the photopolymerization of monomer networks embedding BCP particles by DLP. This approach allowed for tight control over the microporosity of BCP walls by adjusting the camphene content. As the camphene content increased from 40 to 60 vol%, the microporosity increased from similar to 38 to similar to 59 vol%. Consequently, the overall porosity of dual-scale porosity scaffolds increased from similar to 51 to similar to 67 vol%, while their compressive strength decreased from similar to 70.4 to similar to 13.7 MPa. The mass transport ability increased remarkably with an increase in microporosity.National Research Foundation of Korea (NRF) - Korea government (Ministry of Science and ICT) [R2322622, RS-2023-00256327]; BK21 FOUR (BrainKorea21 Fostering Outstanding Universities for Research) - Ministry of education; National Research Foundation of Korea (NRF)This research was supported by the National Research Foundation of Korea (NRF) grant, funded by the Korea government (Ministry of Science and ICT) (Project No. R2322622, Contract No. RS-2023-00256327, International collaboration for bioinspired gradient 3D printing of zirconia bone grafts), and BK21 FOUR (BrainKorea21 Fostering Outstanding Universities for Research) funded by the Ministry of education and National Research Foundation of Korea (NRF).Science Citation Index Expande
Optimal Bore Diameter for Power Dense Traction Motor
No full textThe sine-wave permanent magnet brushless machine (PMSM) and Induction machine (IM) are the favorite motor types for traction applications. Modern permanent magnets (PM) are produced only in a few countries, and PM motors have higher efficiency. However, IM offers a robust, mature, rare-earth-material-free, and cost-effective. This study investigates the possibility of increasing IM efficiency by choosing an optimal bore diameter to reduce copper loss. Optimal bore diameter ensures that the motor operates at flux density levels that maintain a high power factor and give the possibility of increasing stator and rotor slot area to reduce copper loss. The investigation here is based on an experimentally verified FE model of the motor. This study illustrates that the rotor copper loss can be reduced by 25% with the choice of optimal bore diameter at rated voltage and frequency. A further 1% copper loss reduction is possible by introducing a sleeve over the stator slots to reduce air gap harmonics and, thus, surface losses on the rotor side. © 2025 Elsevier B.V., All rights reserved
Importance of Alkaline Phosphatase as a Predictor of Transient Hypoparathyroidism After Parathyroidectomy
No full textBackgroundThere are insufficient studies that have investigated the relationship between temporary hypoparathyroidism (hypoPTH) and the preoperative serum alkaline phosphatase (ALP) level in patients with no renal function disorder who have undergone isolated parathyroidectomy. The aim of this study was to determine whether or not the preoperative serum ALP level could be a marker which could predict the development of postoperative temporary hypoPTH. MethodsThis cross-sectional study included 158 patients aged > 18 years who were diagnosed with primary hyperparathyroidism (PHPT) between 2017 and 2022. The demographic data of the patients were retrieved from the hospital records. The patients were separated into two groups according to the serum calcium level after the parathyroidectomy, as the normal group and the temporary hypoPTH group. The determinants of temporary hypoPTH developing after parathyroidectomy in PHPT patients were investigated using multivariate logistic regression analysis. ResultsTemporary hypoPTH was determined in 25.3% of patients. The mean age and 25-O-HD level were determined to be lower in the patients who developed temporary hypoPTH compared to those who did not. The preoperative serum ALP, parathormone, and 24-h urine calcium levels were determined to be higher in the cases that developed temporary hypoPTH. As a result of the regression analysis, only the serum ALP level was determined to be an independent risk factor predicting the development of temporary hypoPTH (p: 0.005, OR: 1.021). In the ROC analysis, when a cutoff value of 119.5 pg/mL was taken for ALP, it was determined to have 73% sensitivity and 72% specificity for the prediction of the development of temporary hypoPTH. ConclusionsThe most appropriate treatment for symptomatic PHPT patients selected with positive imaging is minimally invasive parathyroidectomy. The most important postoperative complications are hypocalcemia and hypoPTH. The preoperative serum ALP level may be helpful in determining patients at risk of developing temporary hypoPTH following parathyroidectomy.Atilim UniversityThe authors would like to thank all the hospital staff who contributed to the publication of this article.Science Citation Index Expande
Üremik Kardiyomiyopati ile İlişkili Kalp Yetersizliğinde Böbrek Transplantasyonu Sonrası Miyokart İşlevlerinde İyileşme
No full textObjective: Although left ventricular hypertrophy frequently accompanies end-stage renal disease, heart failure (HF) with reduced ejection fraction (EF) is also observed in a subset of patients. In those patients kidney transplantation (KT) is generally avoided due to an increased risk of mortality in addition to the risks associated with HF. This prospective study was designed to follow patients with HF who were being prepared for KT. Methods: Twenty-five patients with HF due to uremic cardiomyopathy (UC) who had suitable donors (Group 1), 22 patients with HF who could not undergo KT due to a lack of kidney donors (Group 3), and 25 KT candidates with normal ventricular function (Group 2) were included in the study. Left ventricular ejection fraction (LVEF), left atrial diameter (LAD), mitral annular systolic velocity (Sm), left ventricular global longitudinal strain (GLS), and left ventricular mass index (LVMI) values were recorded across four sessions, from pre-transplant to six months post-transplantation. Endomyocardial biopsy was performed for detailed examination of the myocardium in patients in Group 1 and Group 3, and cardiac magnetic resonance imaging (MRI) was performed in all three groups before transplantation. Results: In Group 1, LVEF, Sm, and left ventricular global longitudinal strain (LV-GLS) increased significantly, while LAD and LVMI decreased, all reaching normal levels. In contrast, no changes were observed in Group 3 and Group 2 (P < 0.01 for LVEF, P < 0.01 for GLS, P < 0.01 for LAD, and P < 0.01 for LVMI measurements). No differences in cardiac MRI and biopsy findings were observed between Group 1 and Group 3. Conclusion: Since myocardial function improved significantly and normalized in all patients with it has been demonstrated that UC can be reversible when treated with KT.Emerging Sources Citation Inde
Determining the Hydrogen Production Potential of Conmo6se8 Chevrel Phases
No full textIn this study, the ConMo6Se8 (n = 1, 2, 3, and 4) Chevrel phases are investigated by using Density Functional Theory (DFT) to reveal their potential for photocatalytic hydrogen production. The stability conditions of these phases reveal that CoMo6Se8, Co2Mo6Se8, and Co3Mo6Se8 satisfy the thermodynamic and mechanic stability properties, while Co4Mo6Se8 does not satisfy any of these properties. Furthermore, the formation enthalpy of these phases shows that CoMo6Se8, Co2Mo6Se8, and Co3Mo6Se8 can be synthesized experimentally due to having negative formation enthalpy values. Furthermore, the thermal stabilities of the machine-learning (ML) force fields are investigated by ab-initio molecular dynamics (AIMD) calculations. The electronic properties of these phases are also investigated in detail, and it is found that Co3Mo6Se8 has a suitable band gap for photocatalytic water splitting. Concerning the investigation of the valence band and conduction band levels, it is shown that Co3Mo6Se8 has a conduction band minimum level suitable for producing hydrogen. This study is the first attempt to reveal the hydrogen production performance of the ConMo6Se8 (n = 1, 2, 3, and 4) Chevrel phases as far as the literature is concerned, paving the ground for future investigations in this field. © 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.Istanbul Teknik Üniversitesi, IT; Gazi Üniversitesi, (FGA-2023-8982); Gazi Üniversitesi; Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTAK, (120F305); Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTAKScience Citation Index Expande
Patient Safety in Healthcare: A Proposal for Ensuring the Use of Regulation-Compliant Safety Devices
No full textBayrak, Tuncay/0000-0001-6826-4350;Medical devices used in health care should fulfill the requirements of the technical regulations to protect patient health. Difficulties in enforcing stricter rules in the new medical device regulations may negatively affect the continuity of care. This study examines the status of manufacturers' compliance with medical device regulations, based on predefined criteria, and proposes a collaborative action plan and an approach to verify regulatory compliance. We conducted a nationwide survey comprising questions grouped by criteria to understand the status of the manufacturers in terms of compliance with the Medical Device Regulation. Four hundred sixty-seven manufacturers participated in the survey. We achieved a Cronbach's alpha of 0.77, which indicates that the survey is statistically reliable. We applied the independent samples t-test to the responses to determine significant features per question and employed factor analysis to investigate the relationships of the questions. The results of independent samples t-tests showed statistically significant differences across groups in replies to several survey items (p < 0.05), indicating that participants' opinions varied based on their demographic characteristics. We applied Exploratory Factor Analysis to introduce the relationships between the questions. The analysis revealed that manufacturers continue to face substantial challenges in acquiring sufficient knowledge and operational capability to meet MDR requirements. In light of these findings, we focused on the person responsible for regulatory compliance, who plays a central role in maintaining regulatory compliance within manufacturing organizations. We proposed an action plan at the macro level to introduce more effective action plans in cooperation with other stakeholders, including healthcare providers, and a verification approach for regulatory compliance to enhance the Person Responsible for Regulatory Compliance's competence. Manufacturers should implement effective postmarketing clinical follow-up plans involving device-oriented parameters for monitoring in the healthcare system, especially in collaboration with health professionals