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In this paper, the Fuzzy PI controller is used to control the hydraulic servo-valves in Saba iron casting facility in Mobarakeh Steel Company. The electronic and control circuitry in the hydraulic servo-valves was damaged and the oil pressure sensor was not working anymore. The roles were bending and slabs were occasionally broken. Any replacement of the whole servo-valve system was not an option. Therefore, a pressure sensor for the oil outlet is installed and using the input to the control unit, the pressure is controlled. Fuzzy membership functions were defined in PLC to implement a PI Fuzzy Controller. The servo-valve was modeled and simulation results shows good controllability of the process in presence of disturbance. The experimental measurements of the slab pressure proved promising application of Fuzzy PI controller for the system under consideration. [ABSTRACT FROM AUTHOR]

In this paper, a novel concept is introduced to improve the radio-frequency (RF) linearity of partially depleted (PD) silicon-on-insulator (SOI) MOSFET circuits. The transition due to the nonzero body resistance (R \(_{\rm Body}\) ) in output conductance of PD SOI devices leads to linearity degradation. A relation for R \(_{\rm Body}\) is defined to eliminate the transition and a method to obtain transition-free (TF) circuit is shown. 3-D numerical analysis of body-contacted devices is carried out to extract the TF body resistances. To identify the output conductance TF concept and its application to RF circuits, a 2.4-GHz low-noise amplifier (LNA) is further analyzed. Mixed-mode device-circuit analysis is carried out to simultaneously solve device carrier transport equations and circuit SPICE models. Fast Fourier transform calculations on the output signal are performed to compute harmonic distortion figures. Comparing the conventional body-contacted (CBC) and TF SOI LNAs, third harmonic distortion and total harmonic distortion (THD) are improved by 16% and 24%, respectively. Two-tone test is used to analyze third-order intermodulation distortions. Third-order output intercept point is improved in TF SOI LNA by 17% comparing with that of the CBC SOI LNA. The results demonstrate superior advantage in application of TF design concept to SOI MOSFET circuits. [ABSTRACT FROM AUTHOR]

In this paper for the first time, a circuit model for multi-finger I-gate body-contacted silicon-on-insulator MOSFET is presented. The model parameters are adjusted using simulation of a 45 nm SOI nMOSFET. Using the model, typical body voltage for a 35 finger device is obtained and applied to the transistor. The threshold voltage and drain current are obtained for the first transistor and center ones in the multi-finger structure. The drain induced barrier lowering of the center transistor is increased by 30% and off-current 40 times than that of the first transistor. Simulation results verified the I-gate body contact model in lack of controlling the body voltage comparing with the conventional body contacts e.g. H-gate. [ABSTRACT FROM AUTHOR]

Silicon on diamond structure to improve DIBL is presented. The electrical field penetration through the buried insulator of diamond degrades the DIBL. In the new structure, a second, double insulating material, e.g. SiO2 is added on top of the buried insulator and partially covers the diamond. The second insulating material has lower electrical permittivity. Therefore, the fringing field capacitance is smaller. Simulation results of 22 nm silicon-on-diamond transistor shows 18% improvement in DIBL comparing with conventional SOD structure. Lattice temperature increase of 5% is observed in the new structure compared with the conventional SOD. [ABSTRACT FROM AUTHOR]

In this paper, the crosstalk in 32 nm UTB SOI MOSFET is examined by using a new structure, a high resistivity substrate, and a multilayer BOX (SiO2-Diamond). The electrical and thermal characteristics of the conventional SOI and a multilayer BOX SOI are compared, and it is concluded that parasitic capacitances and crosstalk are improved by incorporating multilayer BOX to a HR Substrate. In a conventional HR FD SOI, crosstalk is approximately -121dB, while by incorporating multilayer BOX substrate and increasing the thickness of the Diamond to 100nm, crosstalk can be reduced by 20%. [ABSTRACT FROM AUTHOR]

In this paper, the self-heating effects (SHE) in 45nm Silicon-on-Insulator (SOI) and Silicon-on- Diamond (SOD) are investigated. As a result of the high thermal conductivity of diamond, SHE is much less pronounced in SOD structures. This makes SOD transistors suitable for high power applications were large power density is required. Our hydrodynamic simulation results show that in SOD substrate the generated heat in active transistors not only spreads away in the substrate but also is transferred to the auxiliary non-active transistors on the same die through the diamond film. Simulation results showed up to 8 times more off-current in auxiliary transistors than SOI substrate. The thermal coupling between the neighboring devices in SOD structures represent increased power consumption and device miss-match in analog circuits were high degree of matching is required. [ABSTRACT FROM AUTHOR]

The self-heating effects (SHE) in 45nm Silicon-on-Insulator (SOI) and Silicon-on-Diamond (SOD)structures were investigated. As a result of high thermal conductivity of diamond, SHE is much less pronounced in SOD structures. This makes SOD transistors suitable for high power applications were large power density is required. It was shown that in SOD substrate the generated heat in active transistors not only spreads away in the substrate but also transfers to the auxiliary non-active transistors on the same die through the diamond film. Our hydrodynamic simulation results showed 8 times more off-current in auxiliary transistors than SOI substrate. The thermal coupling between the neighboring devices in SOD structures represent device miss-match in analog circuits were high degree of matching is required. [ABSTRACT FROM AUTHOR]