6,640 research outputs found
Phase Diagram Of The Biham-Middleton-Levine Traffic Model In Three Dimensions
We study numerically the behavior of the Biham-Middleton-Levine traffic model
in three dimensions. Our extensive numerical simulations show that the phase
diagram for this model in three dimensions is markedly different from that in
one and two dimensions. In addition to the full speed moving as well as the
completely jamming phases, whose respective average asymptotic car speeds
equal one and zero, we observe an extensive region of car densities with
a low but non-zero average asymptotic car speed. The transition from this
extensive low average asymptotic car speed region to the completely jamming
region is at least second order. We argue that this low speed region is a
result of the formation of a spatially-limited-extended percolating cluster.
Thus, this low speed phase is present in dimensional
Biham-Middleton-Levine model as well.Comment: Minor clarifications, 1 figure adde
Parity Problem With A Cellular Automaton Solution
The parity of a bit string of length is a global quantity that can be
efficiently compute using a global counter in time. But is it
possible to find the parity using cellular automata with a set of local rule
tables without using any global counter? Here, we report a way to solve this
problem using a number of binary, uniform, parallel and deterministic
cellular automata applied in succession for a total of time.Comment: Revtex, 4 pages, final version accepted by Phys.Rev.
Energy Management for a User Interactive Smart Community: A Stackelberg Game Approach
This paper studies a three party energy management problem in a user
interactive smart community that consists of a large number of residential
units (RUs) with distributed energy resources (DERs), a shared facility
controller (SFC) and the main grid. A Stackelberg game is formulated to benefit
both the SFC and RUs, in terms of incurred cost and achieved utility
respectively, from their energy trading with each other and the grid. The
properties of the game are studied and it is shown that there exists a unique
Stackelberg equilibrium (SE). A novel algorithm is proposed that can be
implemented in a distributed fashion by both RUs and the SFC to reach the SE.
The convergence of the algorithm is also proven, and shown to always reach the
SE. Numerical examples are used to assess the properties and effectiveness of
the proposed scheme.Comment: 6 pages, 4 figure
Relation Between Quantum Speed Limits And Metrics On U(n)
Recently, Chau [Quant. Inform. & Comp. 11, 721 (2011)] found a family of
metrics and pseudo-metrics on -dimensional unitary operators that can be
interpreted as the minimum resources (given by certain tight quantum speed
limit bounds) needed to transform one unitary operator to another. This result
is closely related to the weighted -norm on . Here we
generalize this finding by showing that every weighted -norm on
with 1\le p \le \limitingp induces a metric and a
pseudo-metric on -dimensional unitary operators with quantum
information-theoretic meanings related to certain tight quantum speed limit
bounds. Besides, we investigate how far the correspondence between the
existence of metrics and pseudo-metrics of this type and the quantum speed
limits can go.Comment: minor amendments, 6 pages, to appear in J.Phys.
Feasibility of Using Discriminate Pricing Schemes for Energy Trading in Smart Grid
This paper investigates the feasibility of using a discriminate pricing
scheme to offset the inconvenience that is experienced by an energy user (EU)
in trading its energy with an energy controller in smart grid. The main
objective is to encourage EUs with small distributed energy resources (DERs),
or with high sensitivity to their inconvenience, to take part in the energy
trading via providing incentive to them with relatively higher payment at the
same time as reducing the total cost to the energy controller. The proposed
scheme is modeled through a two-stage Stackelberg game that describes the
energy trading between a shared facility authority (SFA) and EUs in a smart
community. A suitable cost function is proposed for the SFA to leverage the
generation of discriminate pricing according to the inconvenience experienced
by each EU. It is shown that the game has a unique sub-game perfect equilibrium
(SPE), under the certain condition at which the SFA's total cost is minimized,
and that each EU receives its best utility according to its associated
inconvenience for the given price. A backward induction technique is used to
derive a closed form expression for the price function at SPE, and thus the
dependency of price on an EU's different decision parameters is explained for
the studied system. Numerical examples are provided to show the beneficial
properties of the proposed scheme.Comment: 7 pages, 4 figures, 3 tables, conference pape
Analysis of Two-Body Decays of Charmed Baryons Using the Quark-Diagram Scheme
We give a general formulation of the quark-diagram scheme for the nonleptonic
weak decays of baryons. We apply it to all the decays of the antitriplet and
sextet charmed baryons and express their decay amplitudes in terms of the
quark-diagram amplitudes. We have also given parametrizations for the effects
of final-state interactions. For SU(3) violation effects, we only parametrize
those in the horizontal -loop quark diagrams whose contributions are solely
due to SU(3)-violation effects. In the absence of all these effects, there are
many relations among various decay modes. Some of the relations are valid even
in the presence of final-state interactions when each decay amplitude in the
relation contains only a single phase shift. All these relations provide useful
frameworks to compare with future experiments and to find out the effects of
final-state interactions and SU(3) symmetry violations.Comment: 28 pages, 20 Tables in landscape form, 4 figures. Main changes are:
(i) some errors in the Tables and in the relations between the quark-diagram
amplitudes of this paper and those of Ref.[10] are corrected, (ii)
improvements are made in the presentation so that comparisons with previous
works and what have been done to include SU(3) breaking and final-state
interactions are more clearly stated; to appear in the Physical Review
A Framework for Analyzing Factors Influencing Small to Medium Sized Enterprises (SMEs) Ability to Derive Benefit from the Conduct of Web Based Electronic Commerce (EC) - 34 Australian Case Studies
This paper is based on case study research conducted with thirty-four Australian SMEs. It develops a framework for identifying and analysing the factors influencing SMEs ability to derive benefit from conducting web-based EC. Adapting the work of Venkatraman (1994) the paper begins by presenting a model of E-business transformation exploring the relationship between the degree of SME organisational transformation and the potential benefits to be derived from EC. This four phase model is used as a basis for examining the range of internal and external factors that influence SMEs ability to engage in these types of organisational transformations and to derive benefits from EC. The factors are grouped into two categorises: internal and external. From analysis it emerges that depending on their nature, these factors generate inhibiting or enabling forces on an SME’s ability to engage in EC business transformation. More specifically, within any particular phase it is the interaction between these inhibiting/enabling forces that directly influence the ability of an SME to derive benefit from the conduct of web-based EC. Significantly the case study analysis also indicates that where SMEs have already engaged in a high level of EC business transformation (phase 4 Enterprises) their ability to derive further marginal benefit from EC becomes increasingly linked to the nature of factors external to the enterprise
Implications of Shock Wave Experiments with Precompressed Materials for Giant Planet Interiors
This work uses density functional molecular dynamics simulations of fluid
helium at high pressure to examine how shock wave experiments with
precompressed samples can help characterizing the interior of giant planets. In
particular, we analyze how large of a precompression is needed to probe a
certain depth in a planet's gas envelope. We find that precompressions of up to
0.1, 1.0, 10, or 100 GPa are needed to characterized 2.5, 5.9, 18, to 63% of
Jupiter's envelope by mass.Comment: Submitted As Proceedings Article For The American Physical Society
Meeting On Shock Compression Of Condensed Matter, Hawaii, June, 200
A New Design Method and Half-Step Operation for Ultrasonic Stepping Motors
In this paper, a systematic design method and a new half-step operation are proposed for ultrasonic stepping motors (USMs) which are based on the principle of spatially shifted standing vibrations. With emphasis on the combination of the order of vibration mode, the number of spatial phase shifts, the number of electrodes, and the number of simultaneously excited electrodes, the design equations and constraints are newly derived, hence, proposing the design procedure. The finite-element method and impedance measurement are also employed to investigate the vibration of the stator. By borrowing the control idea of electromagnetic stepping motors, the half-step operation is newly applied to this USM so that the step size can be further halved. An 80-step USM is prototyped. The proposed design method and half-step operation are well supported by experimentation.published_or_final_versio
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