Survey on diabetes is one of the popular fields of biomedical signal processing. In this paper, a closed-loop system which utilizes modified Stolwijk-Hardy glucose insulin interaction model is considered. The modified model was derived by adding an exogenous insulin infusion term. Two control algorithms are used for exogenous insulin infusion: a Mamdani type fuzzy logic controller (FLC), and a fuzzy-PID controller. Simulations are performed to assess control function in terms of keeping desired steady state plasma glucose level (0.81 mg/ml) against to exogenous glucose input. Simulation results are notable and significant in terms of controlling blood glucose level (BGL). The control algorithms that applied to the model are firstly proposed, therefore this study is made a contribution to the literature.

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A novel electronically adjustable square/triangular waveform generator has been introduced in this paper. The proposed circuit employs one active element, the multi-output current-controlled current conveyor transconductance amplifier, and one passive component grounded capacitor only. The resistorless realization of the presented generator provides a good advantage in terms of integrated circuit fabrication. In the offered circuit, the frequency and amplitude of the output square wave are electronically tunable by means of relevant bias currents. Additionally, the upper and lower threshold levels are electronically controllable by the respective bias current. On the contrary, electronically adjusting of the duty cycle of output waveform is possible via the external DC current. The generator circuit is simulated with TSMC 0.18[Formula: see text][Formula: see text]m technology parameters and SPICE. Moreover, the introduced circuit is implemented by using commercially available active devices and thus it is also verified experimentally.

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In this work, a new fractional-order sinusoidal oscillator is proposed. The proposed oscillator consists of one fractional-order all-pass filter and one fractional-order lossless integrator blocks. In order to emulate fractional-order capacitors, three different approximation methods the R-C pair, Matsuda and Oustaloup are employed and the results are compared. Three sinusoidal voltage signals with different phases that are controlled by fractional orders are provided by the proposed oscillator topology that is not possible for the classical integer-order case. Grounded passive components are used in the introduced oscillator circuit. Additionally, the output voltage signals are available at the low impedance terminal W of AD844ANs. Moreover, the time constant of the fractional-order all-pass filter can be adjusted accurately by means of second resistor R x in the all-pass filter section. In addition to the simulation results, the proposed fractional oscillator is also implemented to verify the oscillator circuit experimentally. For the case of fractional orders α = 1 and β = 0.5, the measurement results are 10.3 kHz, 43.22° and 67.99°, respectively, while the desired values are 10 kHz, 45° and 67.36°, respectively.