The invention relates to immunostimulatory oligonucleotide compositions. The shielding shell comprises a pair of sidewalls opposite to each other and forming a mating cavity therebetween. The electrical current may be provided to the one or more EAPs according to the sensed parameter of the elongated member andor the balloon of the medical device. Also, by using calculus of variations, the invention describes how the constrained finite horizon optimal control problem can be reduced to solving a linear system of equations. Also disclosed are electric-circuit fabricating system and control program suitable to practice the method.