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Vienna, VA, United States

Kazior T.E.,Defense Systems
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences | Year: 2014

Advances in silicon technology continue to revolutionize micro-/nano-electronics. However, Si cannot do everything, and devices/components based on other materials systems are required. What is the best way to integrate these dissimilar materials and to enhance the capabilities of Si, thereby continuing the micro-/nano-electronics revolution' In this paper, I review different approaches to heterogeneously integrate dissimilar materials with Si complementary metal oxide semiconductor (CMOS) technology. In particular, I summarize results on the successful integration of III-V electronic devices (InP heterojunction bipolar transistors (HBTs) and GaN high-electron-mobility transistors (HEMTs)) with Si CMOS on a common silicon-based wafer using an integration/fabrication process similar to a SiGe BiCMOS process (BiCMOS integrates bipolar junction and CMOS transistors). Our III-V BiCMOS process has been scaled to 200mm diameter wafers for integration with scaled CMOS and used to fabricate radio-frequency (RF) and mixed signals circuits with on-chip digital control/calibration. I also show that RF microelectromechanical systems (MEMS) can be integrated onto this platform to create tunable or reconfigurable circuits. Thus, heterogeneous integration of III-V devices, MEMS and other dissimilar materials with Si CMOS enables a new class of high-performance integrated circuits that enhance the capabilities of existing systems, enable new circuit architectures and facilitate the continued proliferation of low-cost micro-/nano-electronics for a wide range of applications. © 2014 The Author(s).

Hava A.M.,Middle East Technical University | N E.,Defense Systems
IEEE Transactions on Power Electronics | Year: 2011

A high-performance pulsewidth modulation (PWM) algorithm with reduced common-mode voltage (CMV) and satisfactory overall performance is proposed for three-phase PWM inverter drives. The algorithm combines the near-state PWM (NSPWM) method that has superior overall performance characteristics at high modulation index, and MAZSPWM, a modified form of the active zero-state PWM method (AZSPWM1), which is suitable for low modulation index range of operation. Since AZSPWM1 has line-to-line voltage pulse reversals with small zero-voltage time intervals, in its naive form, it causes overvoltages, in particular in long-cable motor drive applications. Obtained by reorganizing the duty cycles of the utilized voltage vectors of AZSPWM1, MAZSPWM has sufficiently long zero-voltage time intervals between pulse reversals such that during pulse reversals, overvoltages are avoided. The combined algorithm performs satisfactorily throughout the inverter operating range and the transition from NSPWM to MAZSPWM and vice versa is seamless. The performance of the proposed algorithm is proven by theory, computer simulations, and detailed laboratory experiments. The paper also shows that the proposed reduced CMV PWM algorithm is effective in reducing the motor leakage current, and it is most beneficial when a small common-mode inductor is included in the drive. © 2011 IEEE.

RCWS (Remote Controlled Weapon System or Station) of the deck-penetrator type and a method for protected reloading of a weapon system that is fed by belt of rounds from an ammunition container that is positioned in the RCWS, wherein the RWCS includes a system for protected reloading of the weapons system, that comprisesa bracket, that on it the ammunition container is mounted, and the bracket is amenable to be propelled via an opening in the deck of the vehicle upon which the RCWS is positioned, unto an inner space of the carrier vehicle and back from this space to the RCWS; and means for movably positioning the bracket, in at least two statesa first state wherein the bracket is positioned inside the inner space of the carrier vehicle and for reloading anew the weapons system; and a second state wherein the bracket is a least substantially embedded in the RCWS for feeding the weapons system by a belt of rounds from inside of the ammunition container that is positioned on the bracket.

A constraint problem may be represented as a digital circuit comprising at least one gate and at least one constrained input or at least one constrained output, or a combination of at least one constrained input and at least one constrained output. A matrix may be generated for each of the at least one gates. A constraint matrix may be generated for the at least one constrained input, the at least one constrained output, or the combination of at least one constrained input and at least one constrained output. A final matrix comprising a combination of each matrix for each of the at least one gates and the constraint matrix may be generated. The final matrix may be translated into an energy representation useable by a quantum computer. The energy of the energy representation may be minimized to generate a q-bit output, and a result of the constraint problem may be determined based on the q-bit output.

Defense Systems | Date: 2014-02-28

A Safe-and-Arm system for the prevention of unintentional operation of an explosive device by interrupting a detonation train, the system employing an interruptive transfer assembly made of silicon and suitable for implementing in a MEMS device, the assembly including a silicon based transfer charge carrier on a porous explosive passageway made by etching, the passageway extending between at least two ports on the circumference of the transfer assembly, and a drive means that can mechanically bring about at least one armed state of a detonation train.

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