Model Prediction-Based Approach to Fault Tolerant Control with Applications

Abstract— Fault-tolerant control (FTC) is an integral component in industrial processes as it enables the system to continue robust operation under some conditions. In this paper, an FTC scheme is proposed for interconnected systems within an integrated design framework to yield a timely monitoring and detection of fault and reconfiguring the controller according to those faults. The unscented Kalman filter (UKF)-based fault detection and diagnosis system is initially run on the main plant and parameter estimation is being done for the local faults. This critical information\ud is shared through information fusion to the main system where the whole system is being decentralized using the overlapping decomposition technique. Using this parameter estimates of decentralized subsystems, a model predictive control (MPC) adjusts its parameters according to the\ud fault scenarios thereby striving to maintain the stability of the system. Experimental results on interconnected continuous time stirred tank reactors (CSTR) with recycle and quadruple tank system indicate that the proposed method is capable to correctly identify various faults, and then controlling the system under some conditions

Bibliographic Review on Distributed Kalman Filtering

In recent years, a compelling need has arisen to understand the effects of distributed information structures on estimation and filtering. In this paper, a bibliographical review on distributed Kalman filtering (DKF) is provided.\ud The paper contains a classification of different approaches and methods involved to DKF. The applications of DKF are also discussed and explained separately. A comparison of different approaches is briefly carried out. Focuses on the contemporary research are also addressed with emphasis on the practical applications of the techniques. An exhaustive list of publications, linked directly or indirectly to DKF in the open literature, is compiled to provide an overall picture of different developing aspects of this area

Experimental Characterization of Electrical Discharge Machining of Aluminum 6061 T6 Alloy using Different Dielectrics

Electrical discharge machining is a non-traditional machining method broadly employed in industries for machining of parts that have typical profiles and require great accuracy. This paper investigates the effects of electrical parameters: pulse-on-time and current on three performance measures (material removal rate, microstructures and electrode wear rate), using distilled water and kerosene as dielectrics. A comparison between dielectrics for the machining of aluminum 6061 T6 alloy material in terms of performance measures was performed. Aluminum 6061 T6 alloy material was selected, because of its growing use in the automotive and aerospace industrial sectors. The experimental sequence was designed using Taguchi technique of L9 orthogonal array by changing three levels of pulse-on-time and current, and test runs were performed separately for each dielectric. The results obtained show that greater electrode wear rate (EWR) and higher material removal rate (MRR) were achieved with distilled water when compared with kerosene. These greater EWR and MRR responses can be attributed to the early breakage of the weak oxide and carbide layers formed on the tool and alloy material surfaces, respectively. The innovative contributions of this study include, but are not limited to, the possibility of machining of aluminum 6061 T6 alloy with graphite electrode to enhance machinability and fast cutting rate employing two different dielectrics.Peer reviewe

Fabrication of submicron planar Gunn diode

We present, for the first time, the fabrication process for a submicron planar Gunn diode in In<sub>0.53</sub>Ga<sub>0.47</sub>As on an InP substrate operating at 265 GHz. A novel two stage lift off method has been developed to achieve a submicron gaps between contacts down to 135 nm with widths up to 120 μm

Improved Distributed Estimation Method for Environmental\ud time-variant Physical variables in Static Sensor Networks

In this paper, an improved distributed estimation scheme for static sensor networks is developed. The scheme is developed for environmental time-variant physical variables. The main contribution of this work is that the algorithm in [1]-[3] has been extended, and a filter has been designed with weights, such that the variance of the estimation errors is minimized, thereby improving the filter design considerably\ud and characterizing the performance limit of the filter, and thereby tracking a time-varying signal. Moreover, certain parameter optimization is alleviated with the application of a particular finite impulse response (FIR) filter. Simulation results are showing the effectiveness of the developed estimation algorithm

A Needs and Value Assessment in Developing a Saudi Board of Respiratory Therapy

ABSTRACT BACKGROUND:RT was primarily introduced in Saudi Arabia by military hospitals beginning in the late 1970s. Currently, Saudi Arabia does not have a certification board for RT and, therefore, all of the RTs in Saudi Arabia who graduated from national colleges do not have credentials. PURPOSE: The purpose of the study was to evaluate the need for developing a board for RT in Saudi Arabia, and also to determine how Saudi RTs perceived the value of certification board for RT. METHODS: Data were collected through a descriptive survey. The survey was used to examine the assessment of need to develop SBRT, and to determine how Saudi RTs perceived the value of certification. The web- link survey was e-mailed to all RTs who are member of the Saudi Society for Respiratory Care (SCRC), which has total of 750 members. The survey consisted of two parts: Assessment of need for SBRT, and perceived value certification tool (PVCT). RESULTS: two hundreds and forty responded with a response rate of 32%. Eighty percent of the participants were male, and 18% were female. Fifty three percent of the participants identified themselves as credentialed RTs, and 46% participants were non-credentialed RTs. The participants’ degree level reported was Associate degree (13%), Bachelor’s degree (63%), Master’s degree (21%), and Doctoral degree (3%). Ninety percent of the participants work for the government institutions, whereas 10 % work for the private institutions. There was no statistically significant difference at the level of 0.05 between credentialed RTs and non-credentialed in terms of the perception towards the development of SBRT (z = -1.81, p= .071). There is also no statistically significant difference between credentialed and non-credentialed (p =. 779) at the level of .05 in terms of how they perceived the certification value. CONCLUSION: These findings can provide SRTs the opportunity to promote and discuss the development of the KSA certification board within the field of RT

The impact of oil revenue fluctuations on the Saudi Arabian economy.

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