Initial State In Order Research Articles

A 1-to-3 GHz 5-to-512 Multiplier Adaptive Fast-Locking Self-Biased PLL in 28 nm CMOS

Based on a self-biased architecture, this paper presents a novel adaptive fast-locking, wide operating range and low-jitter phase-locked loop (PLL). A current injection and adaptive bandwidth technology with minimum area overhead is employed to speed up the loop equilibrium acquisition process, without any adverse impact on the steady-state loop dynamics and the jitter performance. The proposed start-up circuit resets the loop to an appropriate initial state in order to shorten the initial ramp-up interval of the voltage-controlled oscillator (VCO), also resulting in cutting down the pull-in time. In addition, a proportional factor is introduced to give some kind of flexibility in the circuit design optimization. The proposed adaptive fast-locking self-biased PLL (AFL-SPLL) is designed and realized in a prototype based on TSMC 28 nm CMOS process, having a supply voltage of 0.9 V and an area of 0.0281 mm2. This PLL demonstrates a tuning range of 1 to 3 GHz and power consumptions from 0.91 mW at 1 GHz to 4.6 mW at 3 GHz operating frequency. The experimental results show that the capture process has been accelerated by up to 84.7% over large division ratios, yet the capture performance did not deteriorate at all for small division ratios. Meanwhile, the circuit implementation gave almost no area increase and yet achieved a reduction in the lock-in time of about 6.5 times, namely from 23.5 μs (without the adaptive locking) to only 3.6 μs (with the adaptive locking) on the maximum operation frequency condition of 3 GHz.

Delayed collapses of Bose-Einstein condensates in relation to anti-de Sitter gravity.

We numerically investigate spherically symmetric collapses in the Gross-Pitaevskii equation with attractive nonlinearity in a harmonic potential. Even below threshold for direct collapse, the wave function bounces off from the origin and may eventually become singular after a number of oscillations in the trapping potential. This is reminiscent of the evolution of Einstein gravity sourced by a scalar field in anti de Sitter space where collapse corresponds to black-hole formation. We carefully examine the long time evolution of the wave function for continuous families of initial states in order to sharpen out this qualitative coincidence which may bring new insights in both directions. On the one hand, we comment on possible implications for the so-called Bosenova collapses in cold atom Bose-Einstein condensates. On the other hand, Gross-Pitaevskii provides a toy model to study the relevance of either the resonance conditions or the nonlinearity for the problem of anti de Sitter instability.

Quantum quenches of ion Coulomb crystals across structural instabilities. II. Thermal effects

We theoretically analyze the efficiency of a protocol for creating mesoscopic superpositions of ion chains, described in [Phys. Rev. A 84, 063821 (2011)], as a function of the temperature of the crystal. The protocol makes use of spin-dependent forces, so that a coherent superposition of the electronic states of one ion evolves into an entangled state between the chain's internal and external degrees of freedom. Ion Coulomb crystals are well isolated from the external environment, and should therefore experience a coherent, unitary evolution, which follows the quench and generates structural Schr\"odinger cat-like states. The temperature of the chain, however, introduces a statistical uncertainty in the final state. We characterize the quantum state of the crystal by means of the visibility of Ramsey interferometry performed on one ion of the chain, and determine its decay as a function of the crystal's initial temperature. This analysis allows one to determine the conditions on the chain's initial state in order to efficiently perform the protocol.

Fast Identification of Undetectable Transition Faults under Functional Broadside Tests

This paper describes a fast procedure for identifying undetectable transition faults under functional broadside tests. By using reachable states as scan-in states, functional broadside tests avoid overtesting that may occur when scan-based tests are used for detecting delay faults. The proposed procedure is based only on logic simulation, and does not perform test generation of any type. In one of its variations, the procedure uses logic simulation of fully unspecified primary input vectors starting from a known initial state in order to identify a superset of broadside tests that covers all the functional broadside tests. It then uses this superset to identify undetectable transition faults. The procedure identifies large numbers of undetectable transition faults in certain benchmark circuits.

MOLECULAR DYNAMICS SIMULATION OF POPC AND POPE LIPID MEMBRANE BILAYERS ENFORCED BY AN INTERCALATED SINGLE-WALL CARBON NANOTUBE

Using classical all-atom molecular dynamics simulation, we investigated the molecular dynamics of palmitoyloleoylphosphatidylcholine and palmitoyloleoylphosphatidylethanolamine membrane bilayers enforced by a single-wall carbon nanotube. We postulated that an insertion of a single-wall carbon nanotube in the center of lipid membrane "strengthens" ambient lipids and prevents the whole system from further destabilization by high temperatures. We implemented root mean square deviation and root mean square fluctuation analyses of simulated structures from their initial states in order to emphasize the molecular dynamics behavior of these structures during 1000 ps simulation time at different temperatures. The data suggest that an intercalated carbon nanotube restrains the conformational freedom of adjacent lipids and hence has an impact on the membrane stabilization dynamics. On the other hand, different lipid membranes may have dissimilarities due to the differing abilities to create a bridge formation between the adherent lipid molecules. The results derived from this work may be of importance in developing stable nanosystems for construction of novel biomaterials and delivery of various biomolecules in the fields of biosensors, biomaterials, and biophysics.

Adiabatic approximation, Gell-Mann and Low theorem, and degeneracies: A pedagogical example

We study a simple system described by a 2x2 Hamiltonian and the evolution of the quantum states under the influence of a perturbation. More precisely, when the initial Hamiltonian is not degenerate,we check analytically the validity of the adiabatic approximation and verify that, even if the evolution operator has no limit for adiabatic switchings, the Gell-Mann and Low formula allows to follow the evolution of eigenstates. In the degenerate case, for generic initial eigenstates, the adiabatic approximation (obtained by two different limiting procedures) is either useless or wrong, and the Gell-Mann and Low formula does not hold. We show how to select initial states in order to avoid such failures.

Applying computational nanomaterials design to the reactive ion etching of NiO thinfilms—a preliminary investigation

We have developed and proposed a model for reactive ion etching (RIE) processdesign of nickel oxide thin films using a computational materials design based onab initio calculations. On etching NiO, we found that it was necessary to havehydrogen-based reactive gases in the initial state in order to enhance RIE(e.g. NH3,CH4). We strongly suggestthe use of CH4 or any H-basedgas source other than CHF3 to enhance RIE process.

飽和を有する制御系の積分２次性能解析／設計のためのポリトープ的手法の効用と限界

This paper considers a regional quadratic performance analysis and state feedback synthesis method based on a polytopic approach for linear time invariant systems with saturation nonlinearities. In particular, a domain of quadratic performance is defined as a region of initial states in order to satisfy a quadratic performance. In the analysis case, the polytopic approach is theoretically less conservative than both the circle criterion and the existing linear analysis. However, in the synthesis case, the synthesis condition with the polytopic approach is theoretically equivalent to one with the circle criterion or the linear analysis in the meaning of the same achievable domains or quadratic performance levels in spite of obtaining different state feedback controllers respectively. Finally, this paper proposes a synthesis method making use of effectiveness of the polytopic approach.

LMI-based ℒ2 Analysis/Synthesis with Saturating Control via Generalized Sector Approach

This paper considers linear time invariant systems with saturation and/or dead-zone nonlinearities and proposes a regional ℒ2 performance analysis and synthesis method based on new sector bounds for the nonlinearities. In particular, we define a domain of ℒ2 performance as a region of initial states in order to consider both an ℒ2 performance and an exponential stability performance. We show that both the analysis and the synthesis problems can be recast as linear matrix inequality (LMI) optimization problems, where, for the synthesis, the outputs of the nonlinear elements are assumed to be available for the control. Moreover, it is pointed out that the domain of ℒ2 performance is helpful through a numerical example designing an anti-windup control system by using our derived LMI conditions.

Reordering, recrystallization and recovery behaviour of (Co0.78Fe0.22)3 V as a function of the initial state of order

Optical and electron micrography were used to examine the progress of recovery and recrystallization in the (Co-Fe-V) alloy rolled in the initially disordered state and annealed at a range of temperatures, and the results were related to the measurements reported in Part I of this study. The indirect results include a plot of fraction recrystallized at various temperatures against annealing time: unexplained anomalous behaviour was found at the highest temperature. Stacking-faults and antiphase domain boundaries in the recrystallized grains were examined.

Order and recrystallization in deformed Fe[sbnd]70 at.% Co

Abstract Differential scanning calorimetry has been used to study ordering, disordering and recrystallization of cold-rolled Fe[sbnd]70 at.% Co in both the initially ordered and the disordered states. The effect of the initial state of order on the transformation temperatures and energies of both reordering and recrystallization decreases as the rolling reduction increases, until after 90% rolling reduction they are almost unaffected by the initial state of order, suggesting that the initially ordered material is almost completely disordered. The results support a hypothesis that gliding antiphase-boundary-coupled superlattice dislocations leave disorder behind them.

Reordering, recrystallization and recovery behaviour of (Co0.78Fe0.22)3V as a function of the initial state of order

Reordering, recrystallization and recovery behaviour of (Co0.78Fe0.22)3V as a function of the initial state of order

The onset of serrated yielding in Au(Cu) alloys

The onset of serrated yielding in Au(Cu) alloys has been investigated as a function of strain rate, temperature, Cu concentration and initial state of order both in prequenched and furnace cooled specimens. The results have been analyzed in terms of a model proposed by Sleeswijk and McCormick. The parameters m, γ and β describe the increase with strain of vacancy concentration (C c), total dislocation density ( ρ t ) and mobile dislocation density ( ρ m ) resp. Under certain assumptions m and γ can be determined from the stress-strain curve. The main findings are: 1. 1. The value of m found from the onset of serrated yielding and from the stress-strain curve using Saada's theory of vacancy production are the same. 2. 2. The observed concentration dependence of the onset of serrated yielding points to solute atoms as the main obstacles to dislocation motion in the alloys studied. 3. 3. Using conclusion 2 it is found that β = 0.9 ± 0.1. Comparison with γ = 0.86 found from the stress-strain curve points to a proportionality of mobile and total dislocation density. 4. 4. The influence of a change of the initial state of short range order on the onset of separations can be ascribed to changes of the vacancy migration energy by a few hundredths of an eV.

Effects of cold work on silver-rich silver-magnesium solid solution alloys

Abstract The stored energy of cold work and the electrical resistivity of silver-rich silver—magnesium solid solution alloys were measured as functions of true strain, magnesium concentration and the initial state of order. The results were analysed on the assumption that the measured property changes caused by cold work reflect additive changes due to increases in the dislocation density and to the reduction of order. Explicit expressions are given for these components of the stored energy and the resistivity increment. For the alloys with long-range order, property changes due to reduction of order predominate. For the alloys with short-range order, the dislocation density was calculated as a function of magnesium concentration, from the stored energy and the resistivity increment data; the two sets of values of the dislocation density are in fair agreement. For a given strain, the dislocation density increases with magnesium concentration rapidly at first and then tends to level off in concentrated sol...