A New Insight into the PN-Junction Characteristics of ULSI -The Time Dependent Junction Breakdown (TDJB)-

1989 ◽  
Author(s):  
Hideyuki MATSUOKA ◽  
Digh HISAMOTO ◽  
Ryuichi IZAWA ◽  
Eiji TAKEDA
Author(s):  
W. F. Anderson ◽  
I. C. Pyrah ◽  
F. Haji-Ali

AbstractAlthough BS 5930:1981 describes both Menard and self-boring pressuremeter tests, little guidance is given on test methods. A number of techniques, both stress controlled and strain controlled, have been used and it has been shown that for clays the test technique has a significant influence on the derived strength and modulus parameters.When a pressuremeter test is carried out in a clay, it is assumed that shearing occurs under undrained conditions. However, in addition to immediate shear strain, some creep and local consolidation will occur in the soil around the expanding borehole. These two phenomena are time-dependent and variations in test technique will affect the test data and hence the derived strength and modulus values.To obtain a better understanding of these effects, pressuremeter tests have been studied both experimentally and numerically. Experimentally, pressuremeter tests have been simulated by expanding cylindrical cavities in samples of three clays prepared with known stress history and the results compared with numerical predictions where the effects of immediate shear, creep and consolidation can be separated. The experimental results compare well with the numerical predictions.This has given a new insight into the behaviour of clay soils during pressuremeter tests. The results indicate that any simple standardization of pressuremeter test technique should be approached with caution.


2018 ◽  
Vol 17 (07) ◽  
pp. 1850046 ◽  
Author(s):  
Evan Curtin ◽  
Gloria Bazargan ◽  
Karl Sohlberg

A probabilistic approach to characterizing transit times for quantum particles is generalized to a system of more than two spatial regions and applied to the transport of charge in donor-bridge-acceptor systems. The approach is based on applying conditional probability analysis to a discrete representation of the time-dependent probability density as generated by numerical solution of the time-dependent Schrödinger equation for an initially localized electron. To carry out this analysis, it is first necessary to cast the conditional probability analysis approach in matrix form. The results afford a quantification of the electron transit time and may provide a tool to gain insight into the mechanism of charge transport.


2018 ◽  
Vol 32 (26) ◽  
pp. 1850285
Author(s):  
Chun-Yang Wang ◽  
Zhao-Peng Sun ◽  
Ming Qing ◽  
Yu-Qing Xu

The time-dependent barrier passage of a Brownian particle diffusing in the fractional damping environment is studied by using the reactive flux method. Characteristic quantities such as the rate constant and stationary transmission coefficient are computed for a thimbleful of insight into the barrier escaping dynamics. Results show that the barrier recrossing of the fractional damping reactive system is obviously weakened. And the nonmonotonic varying of the stationary transmission coefficient reveals a close dependence of the escaping process on the fractional damping properties. The time-dependent barrier passage of one-dimensional fractional damping reactive process is found very similar to the two-dimensional non-Ohmic case.


2019 ◽  
Vol 18 (11) ◽  
pp. 2766-2772 ◽  
Author(s):  
Deming Han ◽  
Lihui Zhao ◽  
Xuerong Han

By using density functional theory and time-dependent density functional theory, the geometrical, electronic and photophysical properties of six complexes with two ppy-type ligands and one acetylacetone anion around the Ir center have been explored.


2017 ◽  
Vol 114 (31) ◽  
pp. E6457-E6465 ◽  
Author(s):  
Alexandra-M. Reimers ◽  
Henning Knoop ◽  
Alexander Bockmayr ◽  
Ralf Steuer

Cyanobacteria are an integral part of Earth’s biogeochemical cycles and a promising resource for the synthesis of renewable bioproducts from atmospheric CO2. Growth and metabolism of cyanobacteria are inherently tied to the diurnal rhythm of light availability. As yet, however, insight into the stoichiometric and energetic constraints of cyanobacterial diurnal growth is limited. Here, we develop a computational framework to investigate the optimal allocation of cellular resources during diurnal phototrophic growth using a genome-scale metabolic reconstruction of the cyanobacterium Synechococcus elongatus PCC 7942. We formulate phototrophic growth as an autocatalytic process and solve the resulting time-dependent resource allocation problem using constraint-based analysis. Based on a narrow and well-defined set of parameters, our approach results in an ab initio prediction of growth properties over a full diurnal cycle. The computational model allows us to study the optimality of metabolite partitioning during diurnal growth. The cyclic pattern of glycogen accumulation, an emergent property of the model, has timing characteristics that are in qualitative agreement with experimental findings. The approach presented here provides insight into the time-dependent resource allocation problem of phototrophic diurnal growth and may serve as a general framework to assess the optimality of metabolic strategies that evolved in phototrophic organisms under diurnal conditions.


Author(s):  
Joshua Calder-Travis ◽  
Rafal Bogacz ◽  
Nick Yeung

AbstractMuch work has explored the possibility that the drift diffusion model, a model of response times and choices, could be extended to account for confidence reports. Many methods for making predictions from such models exist, although these methods either assume that stimuli are static over the course of a trial, or are computationally expensive, making it difficult to capitalise on trial-by-trial variability in dynamic stimuli. Using the framework of the drift diffusion model with time-dependent thresholds, and the idea of a Bayesian confidence readout, we derive expressions for the probability distribution over confidence reports. In line with current models of confidence, the derivations allow for the accumulation of “pipeline” evidence which has been received but not processed by the time of response, the effect of drift rate variability, and metacognitive noise. The expressions are valid for stimuli which change over the course of a trial with normally distributed fluctuations in the evidence they provide. A number of approximations are made to arrive at the final expressions, and we test all approximations via simulation. The derived expressions only contain a small number of standard functions, and only require evaluating once per trial, making trial-by-trial modelling of confidence data in dynamic stimuli tasks more feasible. We conclude by using the expressions to gain insight into the confidence of optimal observers, and empirically observed patterns.


2021 ◽  
Vol 8 ◽  
Author(s):  
Yeseul Kim ◽  
Byung Mook Weon

Article view statistics offers a measure to quantify scientific and public impact of online published articles. Popularity of a paper in online community changes with time. To understand popularity dynamics of article views, we propose a decay dynamics based on a stretched exponential model. We find that a stretched exponent gradually decreases with time after online publication following a power-law scaling. Compared with a simple exponential or biexponential model, a stretched exponential model with a time-dependent exponent well describes long-tailed popularity dynamics of online articles. This result gives a useful insight into how popularity diminishes with time in online community.


1967 ◽  
Vol 89 (4) ◽  
pp. 418-424 ◽  
Author(s):  
Donald F. Wilcock

The externally pressurized bearing may be considered and analyzed as an hydraulic closed-loop servomechanism. The use of restrictor feed devices introduces an inner loop that reduces the gain. The time-dependent flow due to the change in volume with film thickness creates a “lead” break frequency favorable to stability. Fluid compressibility, on the other hand, leads to a “lag” break frequency which, if it approaches or becomes less than the “lead” frequency, results in bearing instability. Analysis by transfer function furnishes fresh insight into EP bearing behavior.


2007 ◽  
Vol 3 (S248) ◽  
pp. 288-289
Author(s):  
S. C. Unwin ◽  
A. E. Wehrle ◽  
D. L. Meier ◽  
D. L. Jones ◽  
B. G. Piner

AbstractOptical astrometry of quasars and active galaxies can provide key information on the spatial distribution and variability of emission in compact nuclei. The Space Interferometry Mission (SIM PlanetQuest) will have the sensitivity to measure a significant number of quasar positions at the microarcsecond level. SIM will be very sensitive to astrometric shifts for objects as faint as V=19. A variety of AGN phenomena are expected to be visible to SIM on these scales, including time and spectral dependence in position offsets between accretion disk and jet emission. These represent unique data on the spatial distribution and time dependence of quasar emission. It will also probe the use of quasar nuclei as fundamental astrometric references. Comparisons between the time-dependent optical photocenter position and VLBI radio images will provide further insight into the jet emission mechanism. Observations will be tailored to each specific target and science question. SIM will be able to distinguish spatially between jet and accretion disk emission; and it can observe the cores of galaxies potentially harboring binary supermassive black holes resulting from mergers.


Sign in / Sign up

Export Citation Format

Share Document