The optical propagation observed along the positive column of external electrode fluorescent lamps is shown to be an electron plasma wave propagating with the electron thermal speed of (kTe∕m)1∕2. When the luminance of the lamp is 10000–20000cd∕m2, the electron plasma temperature and the plasma density in the positive column are determined to be kTe∼1.26–2.12eV and no∼(1.28–1.69)×1017m−3, respectively.

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We consider the scaling behaviors for fluctuations of the number of Korean firms bankrupted in the period from August 1 2002 to October 28 2003. We observe a power law for the distribution of the number of the bankrupted firms. The Pareto exponent is close to unity. We also consider the daily increments of the number of firms bankrupted. The probability distribution of the daily increments for the firms bankrupted follows the Gaussian distribution in central part and has a fat tail. The tail parts of the probability distribution of the daily increments for the firms bankrupted follow a power law.

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We consider the random sequential adsorption (RSA) of line segments with diffusional relaxation on a one-dimensional lattice by using Monte Carlo method. The line segments with a length k deposit with a probability p or diffuse up to a diffusion length l(l⩽k) with a probability 1−p. We observe a power-law behavior of the coverage fraction θ(t). For the dimer k=2, the empty area fraction decays according to 1−θ(t)=A(l)p0.68(1−p)−0.40(pt)−0.5, regardless of the diffusion length and the adsorption probability. The dynamics of empty area fraction of the dimers is equivalent to the diffusion-limited reaction (DLR), A+A→0, at the long time limits. A single empty site at the RSA corresponds to the reactants A at the DLR. For k⩾4, the empty area fraction decays according to the power law as 1−θ(t)=A(k,l)[(1−p)pt]−α(k,l). For k⩾4, the dynamics of empty area fraction is not interpreted by the kinetics of the diffusion-limited reaction, kA→0. For k⩾3, the model with l>1 stepping corresponds to reactions where the particles (gaps of size l) hop in a correlated way. Thus, our model of l-group-diffusion-limited k-particle reactions is different from those of the ordinary reaction kA→0. We found new power law behavior for l-group-diffusion limited k-particle reactions and the exponents of the power law depend on the hopping length l. We observed a mixed dynamics of the gap creations, splitting, and annihilations for the model at the long time.