Ferit Ozan Akgül

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PURPOSE The purpose of this study was to determine the normal range of the main pulmonary artery diameter (MPAD) by computed tomography (CT) in persons with normal pulmonary artery pressure, and then to evaluate the relationship of the diameter with age, gender, and body surface area (BSA). MATERIALS AND METHODS Between October 2005 and June 2007, among(More)
A total of 168 consecutive patients with predominant rheumatic mitral stenosis were evaluated by transthoracic (TTE) and transesophageal echocardiography (TEE). Of the 168 patients, 35 had previous embolic events (group I) and 133 had no emboli (group II). A total of 77 (45.8%) patients had atrial fibrillation. The frequency of atrial fibrillation was(More)
The effects of sickle cell disease (SCD) on right ventricular (RV) and pulmonary function in SCD patients with pulmonary hypertension is not well-known. The aim of this study was to investigate RV and pulmonary functions in patients suffering from SCD with or without pulmonary hypertension using color tissue Doppler imaging and spirometry. We evaluated 48(More)
BACKGROUND QT dispersion has been proposed to be a predictor of adverse outcomes in a variety of cardiac disease states. The objective of this study was to examine QT dispersion in patients with sickle cell disease (SCD) and to assess the effect of pulmonary hypertension (PHT) on QT dispersion. METHODS We performed Doppler echocardiographic assessments of(More)
Ultra-wideband (UWB) indoor positioning systems based on Time of Arrival (TOA) techniques are considered to be the high precision alternatives to those employing received signal strength (RSS) or Angle of Arrival (AOA) due to their superior time-domain resolution. However, the performance of such systems may easily be degraded by the blockage of the direct(More)
Recently wireless positioning using existing network infrastructure has become an attractive value added application in campus and local area networks. However, many complexities, intrinsic to indoor radio propagation create technical challenges for the localization algorithms to meet indoor positioning requirements. Variety of algorithms using received(More)
—Time of Arrival (TOA) based indoor positioning systems are considered to be the high precision alternatives to other positioning systems employing received signal strength (RSS) or Angle of Arrival (AOA). However, such systems suffer from the blockage of the direct path (DP) and occurrence of undetected direct path (UDP) condition and their performance(More)
— A ray optics based statistical multipath channel model has been developed to describe the indoor multipath propagation including the important parameters such as path gain, time-of-arrival, angle-of-arrival and number of multipath components. Development of such a model is crucial for performance evaluation of indoor positioning systems. Based on a(More)