The present paper proposes an interpretation of the widely scattered states (called synchronized traffic) stimulated by Kerner's hypothesis about the existence of a multitude of metastable states in the fundamental diagram. Using single-vehicle data collected at the German highway A1, temporal velocity patterns have been analyzed to show a collection of certain fragments with approximately constant velocities and sharp jumps between them. The particular velocity values in these fragments vary in a wide range. In contrast, the flow rate is more or less constant because its fluctuations are mainly due to the discreteness of traffic flow. Subsequently, we develop a model for synchronized traffic that can explain these characteristics. Following previous work [I. A. Lubashevsky and R. Mahnke, Phys. Rev. E 62, 6082 (2000)] the vehicle flow is specified by car density, mean velocity, and additional order parameters h and a that are due to the many-particle effects of the vehicle interaction. The parameter h describes the multilane correlations in the vehicle motion. Together with the car density it determines directly the mean velocity. The parameter a, in contrast, controls the evolution of h only. The model assumes that a fluctuates randomly around the value corresponding to the car configuration optimal for lane changing. When it deviates from this value the lane change is depressed for all cars forming a local cluster. Since exactly the overtaking maneuvers of these cars cause the order parameter a to vary, the evolution of the car arrangement becomes frozen for a certain time. In other words, the evolution equations form certain dynamical traps responsible for the long-time correlations in the synchronized mode.

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In assessing the reliability of metallization systems, most researchers focus their attention on long term experiments under conditions of subcritical current densities and study degradation processes that are not related to the formation of fused zones [1,2]. How ever, increased electric powers and other severe work ing conditions (in particular, in high current electron ics) favor the degradation of metallization layers up to their fusion. Special investigations have been devoted to the development of methods for diagnostics of met allization systems [3][4][5], including their operation under high thermal loads leading to local phase transi tions [6,7].The present work was aimed at studying phase tran sitions in metallization systems under conditions of thermal impacts caused by rectangular current pulses with amplitude up to j = 8 × 10 10 A/m 2 and durations within τ i = 100-1000 μs.The experimental setup was analogous to that used in [8] and included a source of rectangular current pulses with amplitude of up to 60 A and durations up to 1 ms, a master oscillator, a digital storage oscillo scope, and a microscope (Metam R1) with "numeri cal" eye glass for determining the length of a fused zone. The measurements were performed on test sam ples with a metallization stripe (length, 3 mm; width, 75 μm; thickness, up to 5 μm) on a semiconductor substrate (Fig. 1, inset A).The main current carrying layer in test structures was made of aluminum, which is the main metal used for the metallization of semiconductors. The substrate was made of phosphorus doped (111) oriented silicon plate with a resistivity of 0.01 Ω cm covered with a 60 μm thick n type epilayer (15 Ω cm), which pre vents shunting of the metallization. Some substrates were covered by additional dielectric layers of silicon oxide (SiO 2 ) or silicon nitride (Si 3 N 4 ) (Fig. 1, inset B). The nitride layer was deposited via reaction of dichlo rosilane with ammonia at reduced pressure (~50 Pa) in a temperature interval of 700-900°C. The thermal oxide layer was grown in a temperature interval of 1150-1250°C by standard technology in a diffusion furnace filled with dry oxygen. Some samples were Abstract-First order phase transitions induced in aluminum metallization layers by the passage of single rectangular current pulses with amplitude up to 8 × 10 10 A/m 2 and durations within 100-1000 μs are consid ered. The formation of local fused zones and their subsequent migration during current passage have been experimentally studied. The main mechanisms of interphase boundary propagation due to heat evolution at the solid/liquid interface under conditions of nonstationary heating of the metal film are established. The velocity of liquid phase propagation (~25 m/s) along the metallization stripe has been determined in exper iment and a method of calculating the length of a fused zone upon the current pulse passage is proposed.

We propose a novel method to obtain non-lens holographic images of micro-objects in white light with diffraction limit quality, based on fourier-spectroscopy principles. We developed a simple method for numerical acquisition of digital holograms of micro-objects at any spectral component from the set of two-dimensional interferograms, registered by fourier-spectrometer. In our experiments we used spectrally-spatial holographic fourier-spectrometer (SSHFS), equipped with supercontinuum light source and CCD camera for registration. Holographic images of several test objects acquired experimentally at different spectral components are presented. Visualization of local spatially-spectral inhomogeneities of micro-objects is discussed through the example of silver berry scaly hair sample.

We deal with the problem of deriving the microscopic equations governing individual car motion based on assumptions about the strategy of driver behavior. We presume the driver behavior to be a result of a certain compromise between the will to move at a speed that is comfortable for him under the surrounding external conditions, comprising the physical state of the road, the weather conditions, etc., and the necessity to keep a safe headway distance between the cars in front of him. Such a strategy implies that a driver can compare the possible ways of further motion and so choose the best one. To describe the driver preferences, we introduce the priority functional whose extremals specify the driver choice. For simplicity we consider a single-lane road. In this case solving the corresponding equations for the extremals we find the relationship between the current acceleration, velocity, and position of the car. As a special case we get a certain generalization of the optimal velocity model similar to the "intelligent driver model" proposed by Treiber and Helbing.