1,869 research outputs found
Tracy-Widom asymptotics for q-TASEP
We consider the q-TASEP that is a q-deformation of the totally asymmetric
simple exclusion process (TASEP) on Z for q in [0,1) where the jump rates
depend on the gap to the next particle. For step initial condition, we prove
that the current fluctuation of q-TASEP at time t are of order t^{1/3} and
asymptotically distributed as the GUE Tracy-Widom distribution, which confirms
the KPZ scaling theory conjecture.Comment: 24 pages, 5 figure
Optimal shunt parameters for maximising wave attenuation with periodic piezoelectric patches
Elastic metamaterials, which have huge potential in wave guiding and attenuation applications, can be built from structures with periodic piezoelectric patch arrays. Passive shunts offer the benefits of simplicity and low cost. In this paper, the effects of the magnitude and phase angle of the shunt impedance on the attenuation constant of a beam with periodic piezoelectric patch arrays were studied in order to determine the optimal shunt that produces the widest and most effective band gaps. The attenuation constants were found to be large when the phase angle is Formula rad and when the magnitude decreases exponentially with the excitation frequency. This corresponds to a negative capacitance circuit, which is the optimal shunt for such systems. The attenuation constant of the system reduces significantly when the impedance deviates from the optimal value suggesting other circuits are less effective. The impedance and band structure of resistive–inductive (R-L), negative capacitance and resistive shunts were investigated. As expected, the negative capacitance circuit produces a large band gap, while the R-L circuit only produces a band gap around its natural frequency. The transmissibilities of a finite system with these circuits demonstrated that vibration transmissions are low within the band gaps. Furthermore, the stability of the negative capacitance circuit built using a dual-output second-generation current conveyor (DO-CCII) was examined by studying the pole diagrams. The system was found to be stable in ideal conditions but unstable when parasitic effects are considered. This suggests that the stability of the system is an important consideration for the implementation of this strategy and the different negative impedance converter designs available in the literature should be studied to find a suitable circuit configuration
The die is cast: Brexit's influence on student career intentions
Brexit, Britain’s referendum to leave the European Union (EU), provided the backdrop for this study, although how or even if it will be implemented is uncertain. Most UK voters supported leaving the EU, yet an overwhelming majority of young people voted to remain. In an environment of economic and labour market ambiguity, we sampled 304 UK university students to examine Brexit’s perceived impact on their career plans. Using Theory of Planned Behaviour, we found that students with higher internal locus of control intended to adapt career plans, although students who identified themselves as British were less proactive. Whilst most students aspired to follow a career path as an employee of a large company, nearly one third intended to become entrepreneurs, a path preferred by twice the number of males as females. Our results provide important insights for post-Brexit planning of educational policy and for businesses and labour markets throughout Europe
Height fluctuations for the stationary KPZ equation
We compute the one-point probability distribution for the stationary KPZ
equation (i.e. initial data H(0,X)=B(X), for B(X) a two-sided standard Brownian
motion) and show that as time T goes to infinity, the fluctuations of the
height function H(T,X) grow like T^{1/3} and converge to those previously
encountered in the study of the stationary totally asymmetric simple exclusion
process, polynuclear growth model and last passage percolation.
The starting point for this work is our derivation of a Fredholm determinant
formula for Macdonald processes which degenerates to a corresponding formula
for Whittaker processes. We relate this to a polymer model which mixes the
semi-discrete and log-gamma random polymers. A special case of this model has a
limit to the KPZ equation with initial data given by a two-sided Brownian
motion with drift beta to the left of the origin and b to the right of the
origin. The Fredholm determinant has a limit for beta>b, and the case where
beta=b (corresponding to the stationary initial data) follows from an analytic
continuation argument.Comment: 91 pages, 8 figure
Building Protein Domain Based Composite Biobricks for Mammalian Expression Systems
The purpose of this RFC is to describe a method that allows the design of protein domain based parts, starting with gene centered information and translate these informations into BBF RFC 25 compatible part. The method is designed to be used in mammalian expression systems
Non-colliding Brownian bridges and the asymmetric tacnode process
We consider non-colliding Brownian bridges starting from two points and
returning to the same position. These positions are chosen such that, in the
limit of large number of bridges, the two families of bridges just touch each
other forming a tacnode. We obtain the limiting process at the tacnode, the
"asymmetric tacnode process". It is a determinantal point process with
correlation kernel given by two parameters: (1) the curvature's ratio \lambda>0
of the limit shapes of the two families of bridges, (2) a parameter \sigma
controlling the interaction on the fluctuation scale. This generalizes the
result for the symmetric tacnode process (\lambda=1 case).Comment: 21 pages, 1 figure, LaTeX; Includes a further representation of the
kerne
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