In this paper we have presented a new design of fault tolerant comparator with a fault free hot spare. The aim of this design is to achieve a low overhead of time and area in fault tolerant comparators. We have used hot standby technique to normal operation of the system without interrupting and dynamic recovery method in fault detection and correction. The circuit is divided to smaller modules for ease of testing and one hot spare is used for reconfiguration. Complexity, time and area overhead of designed fault tolerant comparator are more effective in compared recent methods.

In this paper, a new open-switch fault diagnosis method is proposed for the six-phase AC-DC converter based on the difference between the phase current and the corresponding reference using an adaptive threshold. The open-switch faults are detected without any additional equipment and complicated calculations, since the proposed fault detection method is integrated with the controller required signals. The proposed fault-tolerant technique reduces the value of overcurrent and total harmonic distortion (THD) on the healthy and faulty phases, by considering the redundancy mode of space vectors in space vector pulse width modulation (SVPWM) and changing the switching signals in fault regions. This technique is performed without adding any legs, switches or triode for alternating currents (TRIAC) to the circuit. Finally, the proposed fault-tolerant technique is evaluated by MATLAB simulation and the results show its effectiveness.

Construction in near fault regions is of specific importance for which safety should be considered against seismic faults. Fault rupture zone is a region that civil construction receives highest damage from near fault zone effects such as surface fractures, strong ground motion, displacement and landslide in the regions of great slope and rough topography. In this study, first, the three dimensional topography and slope map of the studied area are prepared. The fault rupture zone of North Tehran Fault is calculated after developing the faults density and magnitudes gained from three probable mobile scenarios. Present study suggests a fault rupture zone of 2.2 to 1 km for North Tehran Fault.

Most of the megacities are located near the active faults. Ground motions in the vicinity of the active faults are associated with two main phenomena so called rupture directivity and fling effects. Therefore, it is important for earthquake resistance design and seismic hazard mitigation to evaluate the characteristics of near-fault ground motions in the megacities. In this paper, the near-fault ground motion was simulated using kinematic model for Tehran City, the capital of Iran. Tehran city was developed along the North Tehran Fault (NTF), which assumed to be the most probable seismic source for the city. Kinematic models are efficient tools to simulate long-period ground motions including slip heterogeneity (Asperities) on the fault and underground geology. Here, the near-fault ground motions are generated assuming NTF scenario using kinematic finite fault model. Then, the variations of faulting parameters such as rise time, maximum slip, rupture velocity, and site to fault distance on the near-fault pulse characteristics are numerically examined and discussed.

The right movement of the trade in the current society needs the government's supervision beside to investors trust to the tradesman.Something that encourages the investors to invest and makes them hopeful is assurance of maintaining the money, hoping to get benefit and banning the trademan to waste it. A trademan who uses the people's trust and gathers their money and does the trade, should exceed taking care of the people's money. Any kind of encroachment or dissipation of the trade man is regarded fault and leads to trade man to the fault bankruptcy conviction. The present paper considers the different aspects of fault bankruptcy.

This article investigates the problem of simultaneous attitude and vibration control of a flexible spacecraft to perform high precision attitude maneuvers and reduce vibrations caused by the flexible panel excitations in the presence of external disturbances, system uncertainties, and actuator faults. Adaptive integral sliding mode control is used in conjunction with an attitude actuator fault iterative learning observer (based on sliding mode) to develop an active fault tolerant algorithm considering rigid-flexible body dynamic interactions. The discontinuous structure of fault-tolerant control led to discontinuous commands in the control signal, resulting in chattering. This issue was resolved by introducing an adaptive rule for the sliding surface. Furthermore, the utilization of the sign function in the iterative learning observer for estimating actuator faults has not only enhanced its robustness to external disturbances through a straightforward design, but has also led to a decrease in computing workload. The strain rate feedback control algorithm has been employed with the use of piezoelectric sensor/actuator patches to minimize residual vibrations caused by rigid-flexible body dynamic interactions and the effect of attitude actuator faults. Lyapunov's law ensures finite-time overall system stability even with fully coupled rigid-flexible nonlinear dynamics. Numerical simulations demonstrate the performance and advantages of the proposed system compared to other conventional approaches.

Fault migration, an important phenomenon in fault-zones, is neither fully investigated nor defined comprehensively. In this paper, based on observations on Ardekul active fault zone (Eastern Iran), an evolutionary path is considered for strike-slip fault zone. According to this evolutionary path four stages; namely embryonic, youth, maturity and declining have been recognized. This evolutionary path may be generalized over different scales of brittle deformation. The proposed evolutionary path makes the fault migration clear. A case study of Ardekul fault zone is chosen for applying defined fault zone evolution and fault migration. Based on the results, fault migration can be divided into two grades; first, the prior and second, the posterior fault migration. Details of prior migration are distinguished including time of occurrence, stages, types, scales and mechanisms of migration, effective factors on migration and its characteristic features. The posterior migration can be studied from the viewpoint of prior migration. Moreover, the fault migration can be comprehensively classified into two topics; production-oriented fault migration and development-oriented fault migration. Some clay cake experiments are also designed to show the prior and posterior fault migrations.

Nowadays, smart grid implementation is a new and challenging issue. One of the important parameters in the smart grids is their fast and accurate fault locator capability. This capability reduces power outage time, which the repair teams of the power distribution companies mostly lose to find the fault location in a traditional way. The fault allocation in the distribution networks, due to their topological nature (high complexity, intermediate loads, load uncertainty, no homogeneity of lines, etc. ), is a very difficult and different from transmission networks. In this research, fault indicator information is used to deal with multiple result problem introduced by fault locator in distribution networks. In this paper, a forward-backward sweep based method is introduced to find fault location. There are some uncertain parameter in fault location because of the error on the load estimation. There is correlation between these parameters due to similarity of the environmental conditions and customer behavior. Therefore, two methods (Monte Carlo and two-point estimation) are used to model probabilistic parameters on fault location. Finally, the 11-bus test network and the actual 306-bus Sharfabad feeder network in Kerman are utilized to evaluate the proposed method.