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In this paper, we show how quantum Boolean circuits can be used to implement the oracle and the inversion-about-average function in Grover's search algorithm. Before illustrating how this can be done, we present the circuit design principle using the satisfiability (SAT) problem as an example. Then, based on this principle, we show the quantum circuits for two different kinds of applications. The first one is searching a phone book. Although this is a typical example of Grover's algorithm, we show that it is impractical as a real-world application. As the second application, we give the quantum circuits for a more practical application—breaking a symmetric cryptosystem. Although these two applications have quite different types of search criteria, they are both one-way functions and the proposed circuits can actually be generalized to any such problems. In this perspective, we conclude this paper by proposing a template of quantum circuits that is capable of searching the solution of a certain class of one-way functions. [ABSTRACT FROM AUTHOR]

During the past decades, research has progressed on the biomedical implantable electronic devices that require power and data communication through wireless inductive links. In this paper, we present a fully integrated binary phase-shift keying (BPSK) demodulator, which is based on a hard-limited COSTAS loop topology, dedicated to such implantable medical devices. The experimental results of the proposed demodulator show a data transmission rate of 1.12 Mbps, less than 0.7 mW consumption under a supply voltage of 1.8 V, and silicon area of 0.2 mm² in the Taiwan Semiconductor Manufacturing Company (TSMC) CMOS 0.18-μm technology. The transmitter satisfies the requirement of applications relative to high forward-transferring data rate, such as cortical stimulation. Moreover, the employment of BPSK demodulation along with a passive modulation method allows full-duplex data communication between an external controller and the implantable device, which may improve the controllability and observability of the overall implanted system. [ABSTRACT FROM AUTHOR]

Frequency response estimation from closed-loop time-domain experimental data is investigated in this paper for normalized coprime factors (NCF) of a multiple-input-multiple-output (MIMO) plant. Based on a linear fractional transformation (LFT) representation for all the NCFs of plants internally stabilizable by a known controller, this estimation problem is converted into the open-loop nonparametric estimation of an inner transfer function matrix (TFM). An estimate is derived through constrained data-matching. It is proved that when the probing signals are periodic and the NCFs of the auxiliary plant are appropriately selected, the estimate is asymptotically unbiased and with a normal/complex normal distribution. It has been made clear that the estimation bias and the estimation variance are always finite. Computationally tractable procedures are suggested for choosing the desirable auxiliary TFMs. [ABSTRACT FROM AUTHOR]

The author of this article issued a challenge during the 1990s to his fellow researchers: build a robot using muscles of electrically activated polymers that could arm-wrestle a human. In 2003, researchers from the SRI International told him that their technology could be capable of meeting the challenge. This article looks into the facts surrounding the development of artificial muscles in the electronic and ionic categories. Within the electronic category are passive dielectrics, piezo-electric polymers, graft elastomers, liquid crystals and elctrostrictive paper. Within the ionic category are polymer gels, polymer metal composites, conductive polymers, carbon nanotubes and electrorheological liquids.

In general, interval plants with a large uncertainty can not be robustly stabilized by a linear time-invariant controller. The solution presented in this paper is in terms of an overall non linear control law given by the connection of a linear, deterministic, time-varying compensator and of a supervisor. The compensator may assume a finite number of possible different configurations, at least one of the which stabilizes the plant. The task of the supervisor is that of determining the switching instants of a scanning among the elements of the family, according to a suitably defined experimental test on the output of the system. [ABSTRACT FROM AUTHOR]

Theorem 3.3 of the above paper contains some errors, which are discussed in this note. Consequently the necessary corrections are presented. [ABSTRACT FROM AUTHOR]

A fully differential, Class-AB, log domain microbeamformer has been designed in a 60 GHz Si-Ge BiCMOS process. The demonstrated microbeamformer has four input channels and four delays, though the concept can easily be ex- tended to any desirable configuration. The log domain, Class-AR architecture is perfect for medical ultrasound applications due to the fact that the received ultrasound signal has very low amplitude during the major part of the reception period. This leads to very low power consumption because of the Class-AB configuration. The delay-line in the microbeamformer is constructed using a cascade of low input impedance allpass filter cells. A simple implementation of the zero in the allpass filter helps to keep the overall power consumption low. The delay of each allpass filter cell is programmable through the adjustment of a tuning current. Due to the Class-AR architecture used, every source signal must be shaped by a signal preconditioning circuit before connected to the filter cells. A well-known preconditioning circuit has been modified to increase the dynamic range. The modification introduces noise cancellation as well as a method to increases the maximum signal swing. The dynamic range of one preconditioning cell is shown to increase 12.6 dB compared to the classic translinear circuit at a penalty of 15% increase in the power consumption. Signal-to-noise ratio of one allpass filter cell is typically 56.5 dB, and the global dynamic range of the same cell is typically 63.8 dB at an average power consumption of 3.5 mW when 16 input signals are connected to the filter. The power consumption at maximum signal amplitude for the microbeamformer having four input channels and four delays is 3.2 mW with a supply voltage of 2.5 V. In the intended application, the quiescent power consumption is a much better description of the average power consumption. This power consumption is 1.3 mW. [ABSTRACT FROM AUTHOR]

The small signal behavior of a frequency controlled resonant converter is modeled as an equivalent pulsewidth modulation (PWM) converter. By this model, a recently developed simulation algorithm for PWM convener Is modified to simulate both the open loop and closed loop small signal behaviour. Experimental results show that this approach is accurate and efficient. Resonant converters have many advantages over conventional PWM converters. There are many research works on the analysis and design of resonant converters, covering both the steady states and theft small-signal responses.

Theorem 2 of the recent paper [1] presents a trace bound on the solution to the algebraic Riccati equation. In this note we point out that the proof contains contradictory assumptions, and hence the result is invalid. [ABSTRACT FROM AUTHOR]

Reports on the US National Research Council's summary of the main conclusions of its reports on science and technology policies. Issues addressed at the papers; Information on the availability of the summaries.

The article promotes research studies published in "IEEE Transactions on Circuits & Systems" as consistently the most highly mentioned in the field.