In this paper, a new circuit scheme is proposed to reduce the power consumption of Dynamic circuits. In the proposed circuit, an NMOS keeper transistor is used to maintain the voltage level in the output node against charge sharing, leakage current and noise sources. Using the proposed keeper scheme, the voltage swing on the Dynamic node is lowered to reduce the power consumption of wide fan-in gates. Furthermore, the subthreshold leakage current is decreased by using the footer transistor in diode configuration and consequently, the noise immunity is increased in the proposed circuit. Simulation results of wide fan-in OR gates in 90nm CMOS technology demonstrate 48% power reduction and 1. 65× noise-immunity improvement at the same delay compared to the conventional Dynamic circuit for 32-bit OR gates.

In this paper, a new Dynamic circuit is proposed to reduce power consumption of tag comparators. To reduce the power consumption in the proposed Dynamic circuit, NMOS transistors are used to precharge the Dynamic node. In this way, voltage swing on the Dynamic node is decreased and hence the power consumption is reduced. Simulation of wide fan-in OR gates and 40-bit tag comparators are done using HSPICE simulator in a 90nm CMOS technology model. Simulation results exhibit 42% power reduction and 1. 68× noise-immunity improvement at the same delay compared to the conventional Dynamic circuit for 32-bit OR gates. Moreover, simulation results demonstrate 52% and 16% reduction in the power consumption and delay of the proposed tag comparator, respectively, at the same noise immunity compared to the conventional one.

Dynamic circuits offer a promising solution due to their low power consumption and high performance compared to static ones. However, Dynamic circuits have their limitations, particularly in terms of robustness. This article presents a new Dynamic circuit that reduces power consumption and delays for high-fan-in OR gates without significant loss of robustness.  In the new Dynamic circuit, the pull-down network (PDN) is split to increase the speed. Furthermore, employing a reference circuit decreases the conflict current that occurs between the PDN and keeper transistors. For this purpose, the reference circuit replicates the leakage current of the PDN. Therefore, the power and delay of the presented circuit are reduced. In addition, the sub-threshold leakage current and hence the leakage power are decreased in the PDN because of the body effect. The results of simulating high fan-in OR gates in a 90nm CMOS technology show 45% and 53% reduction in delay and power consumption, respectively while maintaining the same level of robustness as the conventional circuit for 64 inputs OR gates. Moreover, the tag comparator designed with the presented circuit shows a 2.65 times improvement in the figure of merit compared to the conventional design.

Magnetic gears in comparison with mechanical type have a lot of features like high reliability, low vibration and acoustic noise, overload protection, input and output shafts insulation, and less repair and maintenance requirements. Having a semi-analytic model based on the magnetic equivalent circuit (MEC) compared with the finite element method can reduce the time needed in the preliminary stages of the design process. In this paper, a two-dimensional modeling of a coaxial magnetic gearbox based on a MEC is presented using the nodal analysis method. Using the proposed model, the magnetic potentials of the circuit nodes are first obtained and the magnetic field distribution, fluxes, inner and outer rotor torque are determined in different parts of the gear. In t his modeling, a Dynamical model of the gear is presented. Using this model, the torque-angle characteristic, torque ripple and pullout torque of the gear are extracted. In addition, the effect of the load torque variation on the MG Dynamics is evaluated. Finally, in order to validate the proposed model, the model results are compared with the finite element analysis.

Due to the lack of measurements in many regions, wave characteristics are estimated using different methods. Wave climate hindcasting/forecasting is mostly conducted by numerical models or empirical methods. Until now, different empirical methods have been developed for wave hindcasting. However, with the development of high speed processors, several sophisticated numerical models have been developed for wave prediction. These models are mostly phase-averaged spectral wave models developed in three generations. In the last two decades, third generation wave models have been used widely in academic and practical projects. In this regard, Port and Maritime Organization has produced his own model, PMO Dynamic. This model has been developed as a part of first three phases of Monitoring and Modeling of Study of Iranian Coasts project. PMO Dynamic package is a software available for engineering purposes. It has several modules that have been developed for different objectives. Wave model is the module which is used for the generation and transformation of wind waves in coastal areas. In this paper, in order to test the PMO Dynamic model capabilities, it has been applied for the prediction of wave parameters in Bushehr Bay and the results have been compared with MIKE21 SW model and measured data.

Background: In intertrochanteric fractures، Dynamic hip screw (DHS) is the most frequently used tool، but several studies did not give good results for this device in reverse-oblique and transverse fractures. Current study aimed to compare fixation results of reverse-oblique intertrochanteric and short-segment subtrochanteric fractures using Dynamic condylar screw (DCS) and DHS in patients referred to Alzahra and Kashani Hospitals in Isfahan, Iran.Methods: In a cross-sectional study، medical files of the patients referred to emergency units of the two hospitals who were diagnosed with intertrochanteric or subtrochanteric fractures and underwent DHS or DCS surgery more than 6 months before were assessed; they were invited for follow-up visit and examination. Written consent forms were taken from all the patients upon their entry; and they were examined in terms of complications including nonunion and failure of device and level of fracture improvement. These cases were evaluated by simple radiography ,too. Results obtained from examination of patients in addition to demographic information were recorded in the data collection form for each patient.Findings: Perfect union was observed in 14 (of 25) patients in DHS group and 21 (of 25) patients in DCS group (56% vs. 84%) six months after the surgery. Bone union was significantly better in DCS group (P=0.031). In addition, six months after the surgery, the devices used in 14 people in DHS group and 24 people in DCS group were fixed and the difference between the two groups was significant (P=0.001). 14 and 24 patients had total recovery in DHS and DCS groups، respectively (20% vs. 44%) with a significant difference (P=0.020).Conclusion: Considering obtained results, it can be concluded that using DCS is recommended over DHS due to severity of pain, bone union and fixation of the device.

circuit breakers (CBs) play an important role in protection of the components used in power systems such as transformers and generators. Therefore, the condition assessment of CBs are really important. The interruption chamber of high voltage CBs is one of the most prominent part including moving and fix arc and main contacts. The operation of CBs under short circuit currents or the high number operations under rated-current leads to the erosion of contacts due to the high temperature or abrasion. The assessment of this part due to difficulty in direct access to it is a main problem. Dynamic resistance measurement (DRM) is an indirect assessment method of contacts used in HVCB. This paper provides a comprehensive FEM-based simulations via COMSOL to assess the impacts of intentional failures in contacts on DRM profile. Subsequently, it has been attempted to develop a fuzzy method to evaluate the failure risk of CBs. The proposed algorithm has been verified through experimental results.

In this paper, the influence of the rotor circuit on the characteristics of the brushless doubly-fed induction machine (BDFIM) is investigated. For this purpose, a Dynamic model is provided for the nested-loop BDFIM. The model is based on the coupled circuits of the stator windings and the rotor loops. By using the winding function method, the self-and mutual-inductances of the coupled circuits are obtained as functions of the rotor position and design parameters. This model is used as a fast tool to predict the Dynamic performance of the BDFIM and is verified by means of time-stepping Finite Element Analysis (FEA). Using the provided Dynamic model, some characteristics of the BDFIM such as the Joule loss and the magnetic coupling between the power and control windings at no-load conditions are studied. Using the developed model, the effect of the number and the arc span of the rotor loops on the no-load characteristic of the BDFIMs is studied.

One of the issues of reliable performance in the power grid is the existence of electromechanical oscillations between interconnected generators. The number of generators participating in each electromechanical oscillation mode and the frequency oscillation depends on the structure and function of the power grid. In this paper, to improve the transient nature of the network and damping electromechanical fluctuations, a decentralized robust adaptive control method based on Dynamic programming has been used to design a stabilizing power system and a complementary static var compensator (SVC) controller. By applying a single line to ground fault in the network, the robustness of the designed control systems is demonstrated. Also, the simulation results of the method used in this paper are compared with controllers whose parameters are adjusted using the PSO algorithm. The simulation results show the superiority of the decentralized robust adaptive control method based on Dynamic programming for the stabilizing design of the power system and the complementary SVC controller. The performance of the control method is tested using the IEEE 16-machine, 68-bus, 5-area is verified with time domain simulation.