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The structure and the dynamics of the gas-liquid phase interface of the three-dimensional Lennard-Jones (12-6) particle system are studied using nonequilibrium molecular dynamics simulation. Heat flux maintains the system into a gas-liquid coexisting state with a steady interface. In the steady state, the interface shows an asymmetric structure and this is well described by a free energy density model with an asymmetric double-well form. When the system approaches to the steady state, a gas of the temperature profile appears between each phase and the gap value is relaxed to that in the steady state following $1/\sqrt{t}$ for large t. It is observed that heat resistance exists in gas-liquid interface in this scale. [ABSTRACT FROM AUTHOR]

Flow simulation with a particle dynamics method is studied. The fluid is made of hard particles which obey the Newtonian equations of motion and the collisions between particles are elastic, that is, energy and momentum are conserved. The viscosity appears autonomously together with the local equilibrium state. When a particle collides with a nonslip boundary, a new velocity is given randomly from the thermal distribution if the wall is isothermal, or a random reflection angle is selected if the wall is adiabatic. Shear viscosity is estimated from simulations of plane Poiseuille flow together with the confirmation that the system obeys the Navier–Stokes equation. Flows past a cylinder are also simulated. Depending on the Reynolds number up to 106, flow patterns are properly reproduced, and Kármán vortex shedding is observed. The estimated values of drag coefficient show quantitative agreement with experiments. [ABSTRACT FROM AUTHOR]

The distribution of life span of families known as "skewed profile" is shown to be well-fitted by q-exponential function. It implies the mortality of the families has age-dependent form of ∝1/(1-αt). This feature is also reproduced by the so-called "size-free" model which was proposed by the present authors. [ABSTRACT FROM AUTHOR]

The traffic flow near the jamming transition is numerically studied by computer simulations of a coupled-map model. Just above the transition, a variety of velocities with which the traffic jams propagate are observed. The entropy of the traffic flow becomes maximum at the same time. Moreover, the current-concentration relation obtained by local measurements shows clear double-valued behavior near the critical concentration. From these properties, the traffic flow can be said as maximally complex near the critical concentration. [ABSTRACT FROM AUTHOR]