74 research outputs found

    Neural Network-Based Equations for Predicting PGA and PGV in Texas, Oklahoma, and Kansas

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    Parts of Texas, Oklahoma, and Kansas have experienced increased rates of seismicity in recent years, providing new datasets of earthquake recordings to develop ground motion prediction models for this particular region of the Central and Eastern North America (CENA). This paper outlines a framework for using Artificial Neural Networks (ANNs) to develop attenuation models from the ground motion recordings in this region. While attenuation models exist for the CENA, concerns over the increased rate of seismicity in this region necessitate investigation of ground motions prediction models particular to these states. To do so, an ANN-based framework is proposed to predict peak ground acceleration (PGA) and peak ground velocity (PGV) given magnitude, earthquake source-to-site distance, and shear wave velocity. In this framework, approximately 4,500 ground motions with magnitude greater than 3.0 recorded in these three states (Texas, Oklahoma, and Kansas) since 2005 are considered. Results from this study suggest that existing ground motion prediction models developed for CENA do not accurately predict the ground motion intensity measures for earthquakes in this region, especially for those with low source-to-site distances or on very soft soil conditions. The proposed ANN models provide much more accurate prediction of the ground motion intensity measures at all distances and magnitudes. The proposed ANN models are also converted to relatively simple mathematical equations so that engineers can easily use them to predict the ground motion intensity measures for future events. Finally, through a sensitivity analysis, the contributions of the predictive parameters to the prediction of the considered intensity measures are investigated.Comment: 5th Geotechnical Earthquake Engineering and Soil Dynamics Conference, Austin, TX, USA, June 10-13. (2018

    Flux vacua in DBI type Einstein-Maxwell theory

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    We study compactification of extra dimensions in a theory of Dirac-Born-Infeld (DBI) type gravity. We investigate the solution for Minkowski spacetime with an S2S^2 extra space as well as that for de Sitter spacetime (S4S^4) with an S2S^2 extra space. They are derived by the effective potential method in the presence of the magnetic flux on the extra sphere. We also consider the higher dimensional generalization of the solutions. We find that, in a certain model, the radius of the extra space has a minimum value independent of the higher-dimensional Newton constant in weak-field limit.Comment: 13 pages, no figure. A reference added, typos fixe

    Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine

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    [This corrects the article DOI: 10.1186/s13054-016-1208-6.]

    Nurses' perceptions of aids and obstacles to the provision of optimal end of life care in ICU

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    Contains fulltext : 172380.pdf (publisher's version ) (Open Access

    Development and experimental validation of finite element models for a prestressed lead extrusion damper

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    The emerging trend in earthquake-resistant structural design is to dissipate some part of the seismic input energy through energy-dissipating devices (EDDs). A prominent candidate to serve this purpose is the lead extrusion damper (LED), which dissipates seismic energy by the extrusion of lead through the displacement of a bulged shaft. The LEDs should be designed as they meet the demands of the host structural system. Hence, predicting the force–displacement relation and energy dissipation characteristics of the LED is essential. To serve this purpose, comprehensive three-dimensional finite element models (FEMs) were developed in this study to simulate the cyclic behavior of a prestressed LED. The methodology consisted of performing coupon tests, the development of FEMs, and experimental verification. Coupon tests were performed for lead and steel to simulate the nonlinear material behaviors better. The models were validated against the experimental results of the LED and a steel beam-to-column connection. In general, the adapted model satisfactorily captured the experimental results. The maximum differences in the maximum force and dissipated energy predictions were about 7.5% for the generated FEMs. In addition, the mean relative difference in predicting damper forces for eight LEDs selected from the literature was about 6%. The low relative differences between the models and experiments demonstrated that the adapted FEM could reliably estimate the cyclic response of the LEDs. It can be stated that the adapted three-dimensional finite element modeling strategy can be utilized robustly for design purposes. © 2023 Institution of Structural Engineers121M719; Istanbul Teknik Üniversitesi, ITThe study was supported by TUBITAK 1001 research project 121M719. The experimental study was conducted in the Structural and Earthquake Engineering Laboratory (STEELab) of Istanbul Technical University. All the support is gratefully acknowledged. Additionally, the authors express their sincere thanks to Dr. Vishnupriya and her co-authors for sharing their experimental data.The study was supported by TUBITAK 1001 research project 121M719 . The experimental study was conducted in the Structural and Earthquake Engineering Laboratory (STEELab) of Istanbul Technical University . All the support is gratefully acknowledged. Additionally, the authors express their sincere thanks to Dr. Vishnupriya and her co-authors for sharing their experimental data

    Evaluation of injuries in professional turkish football players [Profesyonel tĂŒrk futbolcularinda travmanin degerlendirilmesi]

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    Aim: It is important to evaluate the injury patterns and anatomic localization of the injuries according to the playing position for the prevention of injuries and reduction of injury cost in football which is the most popular in the world. The purpose of this study was to evaluate the injury pattern and anatomical localization of injuries. Method: The injury pattern was evaluated with a questionnaire with the participation of 510 football players playing for the teams attending the First and Second Professional Turkish Leagues. Result: For different playing positions abrasions were 64.55-85.42%, muscular strains were 52.06-64.58%, joint sprains were 19.58-49.37% and fractures were 2.58-6.39% present. Regardless from the playing position lower extremity injuries were the most common injuries detected (60.5%). Conclusion: It was suggested that these data would be helpful for the reduction of injury risks and the costs besides with proper onsite precautions

    Myocarditis and Early Markers of Cardiac Response Associated with Scorpion Stings in Children

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    PubMedID: 30257800Introduction: A clinical course ranging from mild local findings to life-threatening systemic findings may occur after scorpion stings. The purpose of this study was to identify priority markers indicating scorpion sting–related cardiac involvement. Methods: Our study was performed between July 2014, and September 2015 in the Çukurova University medical faculty pediatric emergency department, in Adana, Turkey. Patients admitted with scorpion sting–related cardiac involvement and a control group consisting of patients with no scorpion sting–related cardiac involvement were included in the study. Troponin I at time of presentation and at 6 and 24 h, N-terminal prohormone of brain natriuretic peptide (NTproBNP), ejection fraction as determined by echocardiography at 24 h, and peak and end of T wave (Tp-e) and Tp-e/QTc ratios with echocardiography at 24 h were evaluated. Results: A patient group consisting of 7 cases of scorpion envenomation–related myocarditis and a control group of 30 cases of scorpion intoxication without myocarditis findings were enrolled. Statistically significantly high glucose, white blood cell values, creatine kinase MB, troponin I, and NTproBNP values were identified in the scorpion sting–related myocarditis group (P<0.05). Ejection fractions determined by echocardiography at time of presentation were significantly lower in the patients with myocarditis compared with the control group (P<0.05). A statistically significant difference was identified between Tp-e/corrected QT interval (QTc) ratios investigated in DI and V2 derivations in patient and control group echocardiograms (P<0.05). Conclusions: We think that use can be made of NTproBNP in addition to echocardiography and troponin I in the early diagnosis of scorpion sting–related myocarditis and that Tp-e and Tp-e/QTc ratios identified via echocardiography can be used as early markers; however, further studies with larger numbers are needed to confirm this. © 2018 Wilderness Medical SocietyTSA-2014-3024This study was supported by the Çukurova University Research Fund (Project No: TSA-2014-3024)
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