Prediction of Dynamical Properties of Flow Over a Three-element Airfoil via Computationally Intelligent Architectures

Cos¸ku Kasnakog˘ lu,MehmetO nder Efe 제어로봇시스템학회 2008 제어로봇시스템학회 국제학술대회 논문집 Vol.2008 No.10

In this paper we study various computationally intelligent architectures for prediction of pressure values and velocity components of flow past a three-element airfoil. Six sensor locations are selected around the airfoil and the goal is to predict the flow behavior at the rear of the airfoil using pressure readings from the remaining five sensors. To make the problem more interesting we require the predictor to estimate the flow twenty time steps ahead of current time. Data is collected from CFD simulations of the flow and predictors are built using four different computationally intelligent architectures: Multilayer Perceptron (MLP), Adaptive Neuro Fuzzy Inference System (ANFIS), Radial Basis Function Neural Network (RBFNN), and Least Squares Support Vector Machine (LS-SVM). Levenberg-Marquardt optimization technique is utilized for parameter tuning purposes. In addition, a simple linear predictor is built as a benchmark for comparing the MLP, ANFIS, RBFNN, and LS-SVM based predictors. It is observed that MLP and ANFIS based predictors achieve the best prediction, and the performace of all predictors are superior to that of the simple linear predictor.

Influence of wall scattering on the early fine structures of measured room impulse responses

Jeon, Jin Yong,Jang, Hyung Suk,Kim, Yong Hee,Vorlä,nder, Michael Acoustical Society of America 2015 JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA - Vol.137 No.3

Gastrointestinal Side Effect Profile Due to the Use of Alendronate in the Treatment of Osteoporosis

SemihAki,NurtenEskiyurt,?lk?Akarırmak,FikretT?z?n,MerihEryavuz,SerapAlper,OktayArpacıo?lu,FatmaAtalay,VuralKavuncu,SirenKokino,?merKuru,KemalNas,?nder?zerbil,G?rsoySava?,?merFarukSendur,DeryaSoy,G?lse 연세대학교의과대학 2003 Yonsei medical journal Vol.44 No.6

Network Analysis Algorithm for the Solution of Discrete Time-Cost Trade-off Problem

Önder Halis Bettemir,M. Talat Birgönül 대한토목학회 2017 KSCE JOURNAL OF CIVIL ENGINEERING Vol.21 No.4

Optimum solution of time-cost trade-off problem has significant importance since it provides the highest profit opportunity. For this reason, exact, heuristic, and meta-heuristic algorithms are adapted to obtain the optimum or near-optimum solution. However, heuristic algorithms may not always converge into the global optimum, while meta-heuristic algorithms require significant computation to converge into global optimum and exact methods are complex for construction planners to implement. Therefore, minimum cost-slope based fast converging network analysis algorithm, which provides optimum or near-optimum solutions, is proposed for discrete time-cost trade-off problem. The algorithm searches the global optimum through the feasible crashing options. Number of feasible crashing options increase tremendously in large projects. Therefore, an elimination algorithm is embedded to reduce the number of crashing options. The crashing option with the lowest unit crashing cost is executed and global optimum is searched by stepwise crashing. Tests on 18 and 63-Activity projects revealed that the network analysis algorithm converges to optimum or near-optimum solution by only one percent of the computational demand of meta-heuristic algorithms. Consequently, the proposed heuristic algorithm is a convenient optimization method for the solution of time-cost trade-off problem.

Risk Assessment for Determining Best Design Alternative in a State-Owned Irrigation Project in Turkey

Önder Ökmen 대한토목학회 2016 KSCE JOURNAL OF CIVIL ENGINEERING Vol.20 No.1

Irrigation projects realized in Turkey are completely financed by the state through internal funds or foreign credits. Private construction companies deliver these projects under the management of State Hydraulic Works, which is a state foundation responsible for managing the country’s water resources. Decisions related to irrigation projects in Turkey are important because of their effect on the agricultural development and high amounts allocated from national budget for their implementation. Exploring the best design among various alternatives at the design development stage is a serious and challenging process that determines the course and success level of irrigation projects. In this regard, this case study introduces a risk assessment procedure experienced in State Hydraulic Works during the design development stage to determine the best design alternative in an irrigation project. Furthermore, the case study includes crucial remarks about another project under construction on which neither State Hydraulic Works nor the contractor company has so far executed risk assessment. While useful decisions were taken associated with design alternatives in the former project, various problems occurred in the latter one during construction because of not applying risk assessment during design development stage.

The Adverse Events and Hemodynamic Effects of Adenosine-Based Cardiac MRI

Thomas Voigtländer,Axel Schmermund,Peter Bramlage,Amelie Elsässer,Annett Magedanz,Hans-Ulrich Kauczor,Oliver K. Mohrs 대한영상의학회 2011 Korean Journal of Radiology Vol.12 No.4

Objective: We wanted to prospectively assess the adverse events and hemodynamic effects associated with an intravenous adenosine infusion in patients with suspected or known coronary artery disease and who were undergoing cardiac MRI. Materials and Methods: One hundred and sixty-eight patients (64 ± 9 years) received adenosine (140 μg/kg/min) during cardiac MRI. Before and during the administration, the heart rate, systemic blood pressure, and oxygen saturation were monitored using a MRI-compatible system. We documented any signs and symptoms of potential adverse events. Results: In total, 47 out of 168 patients (28%) experienced adverse effects, which were mostly mild or moderate. In 13 patients (8%), the adenosine infusion was discontinued due to intolerable dyspnea or chest pain. No high grade atrioventricular block, bronchospasm or other life-threatening adverse events occurred. The hemodynamic measurements showed a significant increase in the heart rate during adenosine infusion (69.3 ± 11.7 versus 82.4 ± 13.0 beats/min, respectively; p < 0.001). A significant but clinically irrelevant increase in oxygen saturation occurred during adenosine infusion (96 ± 1.9% versus 97 ± 1.3%, respectively; p < 0.001). The blood pressure did not significantly change during adenosine infusion (systolic: 142.8 ± 24.0 versus 140.9 ± 25.7 mmHg; diastolic: 80.2 ± 12.5 mmHg versus 78.9 ± 15.6, respectively). Conclusion: This study confirms the safety of adenosine infusion during cardiac MRI. A considerable proportion of all patients will experience minor adverse effects and some patients will not tolerate adenosine infusion. However, all adverse events can be successfully managed by a radiologist. The increased heart rate during adenosine infusion highlights the need to individually adjust the settings according to the patient, e.g., the number of slices of myocardial perfusion imaging. Objective: We wanted to prospectively assess the adverse events and hemodynamic effects associated with an intravenous adenosine infusion in patients with suspected or known coronary artery disease and who were undergoing cardiac MRI. Materials and Methods: One hundred and sixty-eight patients (64 ± 9 years) received adenosine (140 μg/kg/min) during cardiac MRI. Before and during the administration, the heart rate, systemic blood pressure, and oxygen saturation were monitored using a MRI-compatible system. We documented any signs and symptoms of potential adverse events. Results: In total, 47 out of 168 patients (28%) experienced adverse effects, which were mostly mild or moderate. In 13 patients (8%), the adenosine infusion was discontinued due to intolerable dyspnea or chest pain. No high grade atrioventricular block, bronchospasm or other life-threatening adverse events occurred. The hemodynamic measurements showed a significant increase in the heart rate during adenosine infusion (69.3 ± 11.7 versus 82.4 ± 13.0 beats/min, respectively; p < 0.001). A significant but clinically irrelevant increase in oxygen saturation occurred during adenosine infusion (96 ± 1.9% versus 97 ± 1.3%, respectively; p < 0.001). The blood pressure did not significantly change during adenosine infusion (systolic: 142.8 ± 24.0 versus 140.9 ± 25.7 mmHg; diastolic: 80.2 ± 12.5 mmHg versus 78.9 ± 15.6, respectively). Conclusion: This study confirms the safety of adenosine infusion during cardiac MRI. A considerable proportion of all patients will experience minor adverse effects and some patients will not tolerate adenosine infusion. However, all adverse events can be successfully managed by a radiologist. The increased heart rate during adenosine infusion highlights the need to individually adjust the settings according to the patient, e.g., the number of slices of myocardial perfusion imaging.

Brazing in SiH4-doped inert gases: A new approach to an environment friendly production process

Ulrich Holländer,Daniel Wulff,André Langohr,Kai Möhwald,Hans Jürgen Maier 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.7 No.6

Engineering under protective atmospheres or in vacuum allows the production of materials and components, where the absence of oxygen is an essential requirement for a successful processing. Ideally, joining or coating of (and with) metallic materials needs oxide free material surfaces, in order to achieve durable joints or coatings. Using the established technology of brazing in controlled atmosphere, fundamental physical mechanisms for deoxidation of metal surfaces are presented and the role of oxygen and water residue in the process atmosphere is analyzed. Furthermore, the doping of gases with monosilane for generating virtually oxygen-free process atmospheres is introduced and its advantages for an oxygen-free production are discussed.

Computerized analysis of occlusal contacts in bruxism patients treated with occlusal splint therapy

Hasan Önder Gümüş,Halil İbrahim Kılınç,Süleyman Hakan Tuna,Nihal Özcan 대한치과보철학회 2013 The Journal of Advanced Prosthodontics Vol.5 No.3

PURPOSE. Occlusal splints are commonly used to prevent tooth wear caused by bruxism. However, the effects of splints on occlusion are still unclear. Although it is rarely alluded in literature, splints can provoke severe occlusal alterations and other complications. This study was aimed to identify differences in the responses of individuals with bruxism and healthy individuals to a full-arch maxillary stabilization splint in terms of occlusal changes. MATERIALS AND METHODS. Occlusal contacts in 20 (5 male, 15 female) bruxism patients and 20 (5 male, 15 female) controls with normal occlusion were evaluated before and after occlusal splint therapy. T-Scan III, a computerized occlusal analysis system, was used to simultaneously measure occlusion and disclusion times as well as left-right and anterior-posterior contact distributions before splint therapy and 3 months after therapy. Wilcoxon and Mann-Whitney U tests were used for statistical analyses (α=.05). RESULTS. No differences were found in the posterior contact of bruxism patients before and after stabilization splint treatment. However, differences in posterior contact were observed between bruxists and normal individuals prior to treatment, and this difference disappeared following treatment. CONCLUSION. The results of this study showed the use of a stabilization splint may not have an effect on occlusion. However, the area of posterior occlusal contact among bruxists was found to be greater than that of normal individuals. According to this study, the clinical use of splints may be harmless.

Florid osseous dysplasia in a middle-aged Turkish woman: A case report

Buket Önder,Şebnem Kurşun,Bengi Öztaş,Emre Barış,Erdal Erdem 대한영상치의학회 2013 Imaging Science in Dentistry Vol.43 No.3

Florid osseous dysplasia (FOD) is an uncommon, benign, cemento-osseous lesion of the jaws. The etiology of FOD is still unknown. It is often asymptomatic and may be identified on routine dental radiographs. The classic radiographic appearance of FOD is amorphous, lobulated, mixed radiolucent/radiopaque masses of cotton-wool appearance with a sclerotic border in the jaws. In our case the lesion was found incidentally on routine periapical radiographs taken for restored teeth and edentulous areas. For further and detailed examination, a panoramic radiograph and cone-beam computed tomograph (CBCT) were taken. The panoramic radiograph and CBCT revealed maxillary bilateral and symmetrical, non-expansile, well-defined, round, radiopaque masses in contact with the root of the maxillary right second molar and left first molar teeth. Our aim in presenting this case report was to highlight the importance of imaging in diagnosis of FOD.

A linear variation of the thermal expansivity with the isothermal compressibility for ammonia solid III near the melting point

Hamit Yurtseven,Önder Ça lar 한국화학공학회 2010 Korean Journal of Chemical Engineering Vol.27 No.1

The thermal expansivity αp is related to isothermal compressibility κT at various pressures for constant temperatures of 254.6, 274 and 297.5 K close to the melting pressure in ammonia solid III. By analyzing the experimental data for κT according to a power-law formula, a linear variation of αp with the κT is established here close to the solid-liquid transition in ammonia. Anomalous behavior of thermal expansivity αp and the isothermal compressibility κT near the melting pressure is indicative of the λ-type transition in ammonia solid III.