---

An important task in the initial design stages of rapid-transit type systems or "metros" is the allocation of signals and control points. These are placed so as to achieve a specified minimum time-separation between trains (headway), whilst minimizing the amount of signaling equipment but maintaining the highest level of safety. Conventional signaling and control systems are based on the fixed-block principle, whereby the track (or guide way) is divided into sections of predetermined length. A train is only allowed to proceed into a block when that block and usually the next one is clear of traffic. With the moving-block concept, a train can follow a preceding train at a safe braking distance behind the tail of the train. In this paper, the transient performances of the two signaling systems are compared. A multi-train simulator which was originally developed at Birmingham University (U.K.) with a fixed-block algorithm, has been adopted and modified to accommodate the moving block algorithm. Both signaling systems were applied to Singapore Mass Transit Railway (MTR) and the results were compared in terms of train movement and transient performances including headway and station delay under safety and speed restrictions. Results have shown that with a pure moving-block system a considerable improvement in transient performance can be achieved.

---

In this paper, behavior of teleoperation systems with modeling error and delay time error in Smith predictor is discussed. In teleoperation systems, modeling error is inevitable. This paper discusses stability of teleoperation systems with modeling error. First, error of delay time in teleoperation systems by using of Internet as communication channel is considered and the performance of Smith predictor in teleoperation systems with delay time error is discussed. Next, a new structure for teleoperation system is proposed. An adaptive filter is integrated into the new structure for determination of delay time in communication channel. The new structure augments wave variables and Smith predictor to provide an effective method for teleoperation systems. Along with the adaptive filter, this new structure is shown to overcome instability due to the variability of the delay times. Simulations results show significant improvements in the system performance.

---

In this paper, we try to use modeling based on singular perturbation theory, in order to control satellite attitude during the wide rolling angle maneuvering through nonlinear H∞ control strategy. Differential equations describing dynamics of the satellite are presented first, and by choosing the appropriate dynamic model for actuators and based on the standard singular perturbation model, the closed-loop system is created. Next, this model is put into the appropriate form to solve H∞ problem. Then, after solving the HJI equation, the control law is determined. Simulation results for a nominal satellite control based on our approach are finally presented.

---

In this paper a novel process monitoring scheme for reducing the type І and type ІІ error rates in the monitoring phase is proposed. First, the proposed approach uses an augmented data matrix to implement the process dynamic. Then, we apply independent component analysis (ICA) transformation to the augmented data matrix, and eliminate the outliers using the local outlier factor (LOF) algorithm. Finally, the control limit based on the LOF value of the cleaned data are obtained. In the monitoring phase, if the LOF value of each sample exceeds the control limit, fault has occurred; otherwise, data is normal. The proposed method is applied to fault detection in both a simple multivariate dynamic process and the Tennessee Eastman process.  In both processes, type І and type ІІ error rates are witnessed to reduce by considering the process dynamic and performing the LOF algorithm. Results clearly indicate better performance of the proposed scheme compared to the alternative methods.

---

In this paper, an Extended Kalman Filter (EKF) and a model-dependent nonlinear controller over network using the separation principle for Low Earth Orbit (LEO) satellite Attitude Determination and Control Subsystem (ADCS) have been designed. In this context, according to the satellites development trend, ADCS architecture for a broad class of LEO satellites is proposed to stabilize and achieve mission objectives such as precision attitude determination and pointing. This architecture is a Networked Control System (NCS) used to establish connection and communication among control components including sensors, actuators and onboard processors, as well as to share data with other subsystems. Then, by modeling all components of the system, and considering the network effects as a bounded disturbance, the control system is designed to compensate of these effects. For this purpose, estimation and control algorithms including EKF and a model-dependent nonlinear controller is designed such that in addition to achieve desired system performance, the stability of each of them is guaranteed. Afterwards, the nonlinear dynamics model of the satellite in terms of quaternion parameters and angular velocities is presented, and by expression of the separation principle for nonlinear observer and controller design, their convergence and exponential stability conditions based on linearized model of satellite are derived. Proof of theorem shows that the closed-loop system continuously maintained satellite attitude in the specified accuracy range. Finally, simulation results obtained from applying the designed observer and controller on the active satellite in orbit demonstrates the efficiency of the proposed design.