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This paper investigates the exponential stability of some interconnected stochastic control systems with non-trivial equilibria, for which the considered interconnected systems are induced by the composition of some stochastic subsystems. Of particular interest is the notion of stability with respect to a set containing the non-trivial equilibria. It is shown that the exponential stability of the interconnected or composite feedback control systems can be deduced from the stability of the isolated subsystems. Using the preliminary results concerning practical exponential stability of continuous-time stochastic systems that without a common equilibria, we present sufficient conditions for practical exponential stability of the composite system based upon a computable feedback law that would also render the set containing all non-trivial equilibrium solutions of each stochastic subsystem with the same stability. Finally, several illustrative examples are presented to show the applicability of the results.

This paper investigates the exponential stability of some interconnected stochastic control systems with non-trivial equilibria, for which the considered interconnected systems are induced by the composition of some stochastic subsystems. Of particular interest is the notion of stability with respect to a set containing the non-trivial equilibria. It is shown that the exponential stability of the interconnected or composite feedback control systems can be deduced from the stability of the isolated subsystems. Using the preliminary results concerning practical exponential stability of continuous-time stochastic systems that without a common equilibria, we present sufficient conditions for practical exponential stability of the composite system based upon a computable feedback law that would also render the set containing all non-trivial equilibrium solutions of each stochastic subsystem with the same stability. Finally, several illustrative examples are presented to show the applicability of the results.

The paper aims to introduce a method for the analytical formulation of the integral square error (ISE). In this manner, the aim of the research is to create a parametric solution of the ISE for linear continuous feedback control systems while the closed-loop system is stable and the difference between reference and output, or error, is strictly proper. The potential advantage of this technique is that it allows the finding of an analytical solution for the ISE criterion and hence it is well adopted when a parametric solution of the ISE for optimal control problems is needed. This method is also superior to the numerical methods, because it returns the exact solution of the ISE. Comparisons with a powerful numerical method are given to validate the proposed method.

The purpose of this paper is to explore the ability of the system identification technique in detecting a specific gas at a constant concentration level by a single sensor. Metal oxide semiconductor (MOS) gas sensor is used due to its wide range of applicability in gas monitoring systems. Using the Batch computer method, 115 outputs were recorded with sampling time of 0.57 Sec at a concentration level of 2600 (ppm) for Methanol, Ethanol, and Betanol gases. Applying the estimated model, each gas was successfully distinguished.

The purpose of this paper is to explore the ability of the system identification technique in detecting a specific gas at a constant concentration level by a single sensor. Metal oxide semiconductor (MOS) gas sensor is used due to its wide range of applicability in gas monitoring systems. Using the Batch computer method, 115 outputs were recorded with sampling time of 0.57 Sec at a concentration level of 2600 (ppm) for Methanol, Ethanol, and Betanol gases. Applying the estimated model, each gas was successfully distinguished.

The paper aims to introduce a method for the analytical formulation of the integral square error (ISE). In this manner, the aim of the research is to create a parametric solution of the ISE for linear continuous feedback control systems while the closed-loop system is stable and the difference between reference and output, or error, is strictly proper. The potential advantage of this technique is that it allows the finding of an analytical solution for the ISE criterion and hence it is well adopted when a parametric solution of the ISE for optimal control problems is needed. This method is also superior to the numerical methods, because it returns the exact solution of the ISE. Comparisons with a powerful numerical method are given to validate the proposed method.

An alternative algorithm to Pulse Width Modulation (PWM) for pulsed activation of solenoid valves for applying chemicals through agricultural sprayer nozzles is presented. Solenoid valves attached to individual spray nozzles on a modified EMDEK tractor-mounted sprayer system are activated by electronic pulsation to vary the application rate of agricultural chemicals, varying the output by location according to Geographical Information System (GIS) data and a GPS system. A potential advantage of this alternative algorithm over pulse width modulation based systems is the use of lower-cost industrial solenoid valves with slower opening and closing times instead of the more expensive high speed valves normally used in PWM systems.

The control system of a commercial sprayer was modified for variable–rate control of 12 individual solenoid shut off valves spaced 0.5 m apart on a sprayer boom. The variable-rate control system consisted of pulse width modulation (PWM) solenoids, a by pass control valve, and nozzle control system interfaced to a computer. An algorithm was developed to vary application rate across the booms with computing the best possible combinations of pulse width at the optimal boom through the computer control program for nozzles. This algorithm compensates inaccuracy of applying desired application rate due to pressure fluctuations across the booms.

The control system of a commercial sprayer was modified for variable–rate control of 12 individual solenoid shut off valves spaced 0.5 m apart on a sprayer boom. The variable-rate control system consisted of pulse width modulation (PWM) solenoids, a by pass control valve, and nozzle control system interfaced to a computer. An algorithm was developed to vary application rate across the booms with computing the best possible combinations of pulse width at the optimal boom through the computer control program for nozzles. This algorithm compensates inaccuracy of applying desired application rate due to pressure fluctuations across the booms.

An alternative algorithm to Pulse Width Modulation (PWM) for pulsed activation of solenoid valves for applying chemicals through agricultural sprayer nozzles is presented. Solenoid valves attached to individual spray nozzles on a modified EMDEK tractor-mounted sprayer system are activated by electronic pulsation to vary the application rate of agricultural chemicals, varying the output by location according to Geographical Information System (GIS) data and a GPS system. A potential advantage of this alternative algorithm over pulse width modulation based systems is the use of lower-cost industrial solenoid valves with slower opening and closing times instead of the more expensive high speed valves normally used in PWM systems.