Özer, Mahmut | Bal, Abdullah

Article | 2004 | Istanbul University Journal of Electrical and Electronics Engineering4 ( 1 ) , pp.1091 - 1104

In this paper, we investigate dynamics of voltage-gated ionic channels which are of great importance in integrating the information received by neurons. Understanding of dynamical behavior of voltage-gated ionic channels plays a major role for determining underlying mechanism of spike activity and predicting the neuronal behavior. Investigation is carried out based on Hodgkin-Huxley (H-H) mathematical formalism. Ionic channel gate model is discussed briefly. Relaxation phenomenon is studied in the gate variables. Then effects of temperature on dynamics of gate variables are examined. Finally voltage-clamped simulations are carried o . . .ut to determine their dynamic behaviors based on squid giant axon. In this paper, we investigate dynamics of voltage-gated ionic channels which are of great importance in integrating the information received by neurons. Understanding of dynamical behavior of voltage-gated ionic channels plays a major role for determining underlying mechanism of spike activity and predicting the neuronal behavior. Investigation is carried out based on Hodgkin-Huxley (H-H) mathematical formalism. Ionic channel gate model is discussed briefly. Relaxation phenomenon is studied in the gate variables. Then effects of temperature on dynamics of gate variables are examined. Finally voltage-clamped simulations are carried out to determine their dynamic behaviors based on squid giant axon Daha fazlası Daha az

Altan, Aytaç | Köksal, Kerem | Hacıoğlu, Rıfat

Article | 2017 | Karaelmas Fen ve Mühendislik Dergisi7 ( 1 ) , pp.218 - 227

Bu çalışmada, görsel çizgi (rota) takibi için İnsansız Hava Aracı (İHA) üzerinde bulunan 3 eksenli yalpanın dış bozucu etki altında model öngörülü denetimi gerçekleştirilmektedir. İHA ile görsel çizgi takibi için Tanjant Vektör Alan Kılavuz (TVAK) yöntemi kullanılmaktadır. Dış ortam ve kapalı ortamda yapılan testlerde, ön tanımlaması yapılan çizginin görüntü işleme algoritmalarıyla tespiti ve sonrasında TVAK yöntemi kullanılarak rota takip işlemi gerçekleştirilmektedir. İHA’nın alçak ve yüksek irtifa uçuşlarında rota takibi başarım oranları deneysel olarak gözlemlenmektedir. Elde edilen sonuçlar PID denetime sahip yalpadan elde edil . . .en veriler ile karşılaştırılmaktadır. Dış bozucu etki altında TVAK yöntemi ile rota takibi için İHA üzerindeki 3 eksenli yalpanın MPC denetiminde PID ile denetime göre başarılı sonuçlar elde edilmektedir. In this study, Model Predictive Control (MPC) is performed under the external disturbance effect of the 3-axis gimbal on the Unmanned Aerial Vehicle (UAV) for visual line tracking. The Tangent Vector Fields Guide (TVFG) method is used for visual line tracking with UAV. In the tests performed in the outdoor and indoor environments, the pre-defined line is detected with the image processing algorithms and then the line tracking process is performed using the TVFG method. The visual line tracking success rates in the low and high altitude of UAV flight are observed experimentally. The obtained results are compared with data obtained by the gimbal having PID control. The successful results are obtained with MPC control according to PID control of 3 axis gimbal on UAV under external disturbance for visual line tracking using TVFG method Daha fazlası Daha az

Onur, Tuğba Özge | Hacıoğlu, Rıfat

Article | 2017 | Turkish Journal of Electrical Engineering and Computer Sciences25 ( 2 ) , pp.939 - 949

We investigated adaptive algorithms for a Hammerstein block structure in which a static nonlinear block and dynamic linear block are cascaded. The approach considered here is to use generalized orthonormal basis functions in a Hammerstein block structure by using xed pole lter banks. We applied the normalized least mean square approach to the developed adaptive algorithm in order to acquire Hammerstein block structure parameters. Performance comparison of the proposed approach was investigated considering convergence speed and parametric complexity for acoustic echo cancellation application. The results indicated that in the develop . . .ed algorithm along with appropriate selection of xed poles, the algorithm convergences faster and less parametric complexity is provided when compared to direct adaptive Hammerstein algorithms with IIR and FIR linear blocks. We investigated adaptive algorithms for a Hammerstein block structure in which a static nonlinear block and dynamic linear block are cascaded. The approach considered here is to use generalized orthonormal basis functions in a Hammerstein block structure by using xed pole lter banks. We applied the normalized least mean square approach to the developed adaptive algorithm in order to acquire Hammerstein block structure parameters. Performance comparison of the proposed approach was investigated considering convergence speed and parametric complexity for acoustic echo cancellation application. The results indicated that in the developed algorithm along with appropriate selection of xed poles, the algorithm convergences faster and less parametric complexity is provided when compared to direct adaptive Hammerstein algorithms with IIR and FIR linear blocks Daha fazlası Daha az