An improved formalism for quantum computation based on geometric algebra—case study: Grover’s search algorithm

The Grover search algorithm is one of the two key algorithms in the field of quantum computing, and hence it is desirable to represent it in the simplest and most intuitive formalism possible. We show firstly, that Clifford’s geometric algebra, provides a significantly simpler representation than the conventional bra-ket notation, and secondly, that the basis defined by the states of maximum and minimum weight in the Grover search space, allows a simple visualization of the Grover search analogous to the precession of a spin- ${\frac{1}{2}}$ particle. Using this formalism we efficiently solve the exact search problem, as well as easily representing more general search situations. We do not claim the development of an improved algorithm, but show in a tutorial paper that geometric algebra provides extremely compact and elegant expressions with improved clarity for the Grover search algorithm. Being a key algorithm in quantum computing and one of the most studied, it forms an ideal basis for a tutorial on how to elucidate quantum operations in terms of geometric algebra—this is then of interest in extending the applicability of geometric algebra to more complicated problems in fields of quantum computing, quantum decision theory, and quantum information.     

Reliability analysis of nuclear containment without metallic liners against jet aircraft crash

The present study presents a methodology for detailed reliability analysis of nuclear containment without metallic liners against aircraft crash. For this purpose, a nonlinear limit state function has been derived using violation of tolerable crack width as failure criterion. This criterion has been considered as failure criterion because radioactive radiations may come out if size of crack becomes more than the tolerable crack width. The derived limit state uses the response of containment that has been obtained from a detailed dynamic analysis of nuclear containment under an impact of a large size Boeing jet aircraft. Using this response in conjunction with limit state function, the reliabilities and probabilities of failures are obtained at a number of vulnerable locations employing an efficient first-order reliability method (FORM). These values of reliability and probability of failure at various vulnerable locations are then used for the estimation of conditional and annual reliabilities of nuclear containment as a function of its location from the airport. To study the influence of the various random variables on containment reliability the sensitivity analysis has been performed. Some parametric studies have also been included to obtain the results of field and academic interest.     

Optimization of abrasive water jet cutting of ductile materials

Full factorial design of experiments was developed in order to investigate the effects of jet pressure, abrasive mixing rate, cutting feed, and plate thickness upon three response variables, surface finish of cutting wear zone, percentage proportion of striation free area, and maximum width of cut. The set of sixteen experiments was performed on each of the following two ductile materials: AISI 4340 (high strength low alloy steel, hardened to 49HRc) and Aluminum 2219. Analysis of Variance (ANOVA) was performed on experimental data in order to determine the significance of effects of different parameters on the performance measures. It was found that cutting feed and thickness were highly influential parameters, while abrasive mixing rate is influential upon surface roughness only. Strong interaction was found between jet pressure and workpiece material. Multi-criteria numerical optimization was performed in order to simultaneously maximize/minimize different combinations of performance measures.     

Synthesis and Physical Properties of Mn Doped ZnO Dilute Magnetic Semiconductor Nanostructures

Mn doped ZnO nanostructures have been prepared using low temperature simple, quick, and versatile synthesis approach. The structural, microstructural, and vibrational investigations reveal that as prepared nanostructures with low Mn doping concentration have single hexagonal phase and are grown along the preferred c-axis. The X-rays photoelectron spectroscopy demonstrates that the Mn ions are in mixed oxidation states for high doping concentration of Mn, while are in 2+ oxidation state for low concentration into ZnO lattice. The photoluminescence spectrum (PL) exhibits a significant red-shift of 22 nm in the optical band gap of doped ZnO and shows the improved luminescence properties, which makes it potential for its use in the photocatalyst, optoelectronics and solar cell nanodevices. Furthermore, the magnetic measurement of Mn doped ZnO nanostructures exhibits the ferromagnetism at room temperature.     

Chemical Coupled PEDOT:PSS/Si Electrode: Suppressed Electrolyte Consumption Enables Long‑Term Stability

Huge volume changes of Si during lithiation/delithiation lead to regeneration of solid-electrolyte interphase(SEI)and consume electrolyte.In this article,γ-glycidoxypropyl trimethoxysilane(GOPS)was incorporated in Si/PEDOT:PSS electrodes to construct a flexible and conductive artificial SEI,effectively suppressing the consumption of electrolyte.The optimized electrode can maintain 1000 mAh g^−1 for nearly 800 cycles under limited electrolyte compared with 40 cycles of the electrodes without GOPS.Also,the optimized electrode exhibits excellent rate capability.The use of GOPS greatly improves the interface compatibility between Si and PEDOT:PSS.XPS Ar+etching depth analysis proved that the addition of GOPS is conducive to forming a more stable SEI.A full battery assembled with NCM 523 cathode delivers a high energy density of 520 Wh kg^−1,offering good stability.     

BSLPSDN: Base station location privacy via software-defined networking (SDN) in wireless sensor networks

Base station's location privacy in a wireless sensor network (WSN) is critical for information security and operational availability of the network. A key part of securing the base station from potential compromise is to secure the information about its physical location. This paper proposes a technique called base station location privacy via software-defined networking (SDN) in wireless sensor networks (BSLPSDN). The inspiration comes from the architecture of SDN, where the control plane is separated from the data plane, and where control plane decides the policy for the data plane. BSLPSDN uses three categories of nodes, namely, a main controller to instruct the overall operations, a dedicated node to buffer and forward data, and lastly, a common node to sense and forward the packet. We employ three kinds of nodes to collaborate and achieve stealth for the base station and thus protecting it against the traffic-analysis attacks. Different traits of the WSN including energy status and traffic density can actively be monitored by BSLPSDN, which positively affects the energy goals, expected life of the network, load on common nodes, and the possibility of creating diversion in the wake of an attack on the base station. We incorporated multiple experiments to analyze and evaluate the performance of our proposed algorithm. We use single controller with multiple sensor nodes and multiple controllers with multiple sensor nodes to show the level of anonymity of BS. Experiments show that providing BS anonymity via multiple controllers is the best method both in terms of energy and privacy.     

High speed performance of 1.5 mu m compressive-strained multiquantum-well gain-coupled distributed-feedback lasers

1.5 mu m compressive-strained multiquantum-well gain-coupled distributed-feedback lasers have been fabricated on semi-insulating InP substrates with very low parasitic capacitance for studying the laser dynamic characteristics. A maximum 3 dB bandwidth of 12.8 GHz under small signal modulation, a 20 dB down chirping width of 0.33 nm under modulation, a 20 dB down chirping width of 0.33 nm under 5 Gbit/s NRZ pseudorandom modulation, and a low chirping short pulse of 20 ps under gain switching are obtained.<>     

A comparison of the trap properties and locations within GaAs fieldeffect transistors measured under different bias conditions

The activation energy and capture cross section of traps found in GaAs field effect transistors (GaAs FETs) have been measured with both ohmic channel and current saturation bias using a variety of transient, frequency dispersion, and noise spectroscopy techniques. With current saturation bias these effects have been seen in both the transconductance and the output conductance. The results for all methods and bias conditions are compared with those found by others. The relative sensitivity of the techniques and the location of the traps are discussed     

Lowpass and bandpass transadmittance filter using operational amplifier pole

A new topology simultaneously implementing lowpass (LP) and bandpass (BP) transadmittance filtering signals using a single operational amplifier (OA), one capacitor, and two resistors is presented. The input impedance is very high which is essential for cascading without employment of buffers. The circuit uses absolute minimum number of active and passive components. The filter employs pole-model of OA and as such has acquired suitability for extended frequency operation. The circuit permits separate adjustment of natural frequency (ω₀) and quality factor (Q) in an orthogonal manner. The circuit has low sensitivity figures unlike the reported single amplifier biquads. The PSPICE simulation results are included.     

The growth of prebreakdown cavities in silicone fluids and thefrequency of the accompanying discharge pulses

Measurements have been made of prebreakdown cavities in silicone fluids, and of the current pulses that accompany cavity growth. These experiments were carried out in silicone fluids of 0.65, 10, 100 and 1000 cS viscosity. Cavity growth, driven by the electrostatic field, is limited at low viscosities by inertia, and at high viscosities by viscous drag. The electrostatic force on the cavity wall is related to the local field and to the space charge density in the liquid adjacent to the cavity. We are concerned with the relationship between the electrostatic force and the cavity growth, and with the discharges that accompany cavity growth. Discharges occur in well-defined pulse trains: the first pulse in a train generates the cavity, and subsequent pulses are due to discharges within the cavity. Knowing the scaling laws for cavity growth we can use the time between the first and second pulses to estimate the cavity size when the first cavity discharge occurs; this gives a cavity diameter of ~5 to 7 μm. The next pulse cannot occur until the charge from the previous discharge has dispersed. We find that the time between pulses Δt is strongly viscosity dependent; at high viscosities the average time between pulses at is proportional to fluid-viscosity, but in the low viscosity limit the dependence approaches η^1/3. To explain this viscosity dependence we consider three mechanisms: (1) a decrease in charge density due to increase in cavity size; (2) ion detrapping from the cavity wall and drift in the applied field; and (3) diffusion of an impurity species to the cavity surface, charge exchange to create a mobile ion, and its subsequent drift in the field. Our experimental results are consistent with the cavity expansion model, but there is evidence of diffusion effects in low viscosity liquids, and with ion-drift at high viscosities