Abdulrazaq Abubakar

Abstract Robust trajectory tracking of nonlinear robotic manipulators under uncertainty requires controllers whose gains are both theoretically grounded in stability analysis and systematically tuned. Classical controllers such as PID are highly sensitive to gain tuning, whereas conventional sliding mode control suffers from chattering and robustness smoothness trade-offs.

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Investing in the stock market is not absolutely halal or absolutely haram. It mainly depends on the company you invest in. You need to think of it as taking an ownership stake in something. For example, let's take a company like Citibank. This may be an obvious one, but they make their money almost exclusively through interest and interest related stuff. Would it be halal for you to own a business that made its money through interest? No, so that would not be a halal investment.