Percolation properties of growing networks under an Achlioptas process

We study the percolation transition in growing networks under an Achlioptas process (AP). At each time step, a node is added in the network and, with the probability $\delta$, a link is formed between two nodes chosen by an AP. We find that there occurs the percolation transition with varying $\delta$ and the critical point $\delta_c=0.5149(1)$ is determined from the power-law behavior of order parameter and the crossing of the fourth-order cumulant at the critical point, also confirmed by the movement of the peak positions of the second largest cluster size to the $\delta_c$. Using the finite-size scaling analysis, we get $\beta/\bar{\nu}=0.20(1)$ and $1/\bar{\nu}=0.40(1)$, which implies $\beta \approx 1/2$ and $\bar{\nu} \approx 5/2$. The Fisher exponent $\tau = 2.24(1)$ for the cluster size distribution is obtained and shown to satisfy the hyperscaling relation.Comment: 4 pages, 5 figures, 1 table, journal submitte

Force correlations in molecular and stochastic dynamics

A molecular gas system in three dimensions is numerically studied by the energy conserving molecular dynamics (MD). The autocorrelation functions for the velocity and the force are computed and the friction coefficient is estimated. From the comparison with the stochastic dynamics (SD) of a Brownian particle, it is shown that the force correlation function in MD is different from the delta-function force correlation in SD in short time scale. However, as the measurement time scale is increased further, the ensemble equivalence between the microcanonical MD and the canonical SD is restored. We also discuss the practical implication of the result.Comment: 9 pages, 4 figures and Computer Physics Communcations (in press

Influence of Al on glass forming ability and nanocrystallization behavior of cast-iron based bulk amorphous alloy

Cast-iron (CI) based bulk amorphous alloy with compositions of Fe₇₅.₅₋ₓC₆.₀ Si₃.₃B₅.₅P₈.₇Cu₁.₀Alₓ (x = 0, 1 at.%) was synthesized by Cu mold casting. As indicated by increased critical diameters (dmax) for the amorphization, the substitution of Al enhanced the glass-forming ability of the alloy. However, the onset temperature of crystallization (Tₓ) and the range of supercooled liquid region (ΔTₓ) of the alloy decreased upon Al addition from 500 °C and 28 °C to 475 °C and 25 °C, respectively. It was revealed that the decreased thermal stability of the amorphous phase is related to the enhanced crystallization tendency to form primary α-Fe phase. Upon the nanocrystallization of primary α-Fe phase the Al-added alloy shows enlarged Ms of 176 emu g⁻¹, still keeping a reasonable small Hc value of 0.086 Oe. The present study revealed that the minor Al addition enhances not only the glass-forming ability, but also the nanocrystallization behavior of the CI based bulk amorphous alloy

A Study on the Risk Probability of Risk Mitigation Alternatives at Non-Compliance Airport with Runway Strip Criteria

A runway strip is defined as the surface surrounding a runway established or suitable for reducing the risk of damage to aircraft in the event of a runway excursion. This study aims to implement the RSARA and LRSARA models at an airport not meeting the runway strip dimension criteria required by standards for aerodrome physical characteristics. The airport is considering alternatives to secure the runway strip criteria such as the displaced threshold and runway length extension, which is predicted to reduce the runway excursion probability. As the results of this study, it was discovered that the risk probability increases with the increases of the displaced runway distance due to relatively reduced runway length. Therefore, a reduced runway length to meet runway strip criteria may not be the most effective risk mitigation alternative, and it should be acknowledged that such a strategy can harm aviation Safety

The Effects of Aerobic Exercise Training on Blood Lipid Profiles, Fibrinolytic Activities, and Nitric Oxide Levels in High-fat-diet induced Rats

Although exercise training has been utilized to improve vascular function in animals and humans, the impact of moderate intensity exercise training on fibrinolytic activities and nitric oxide (NO) bioavailability has not been well documented. Therefore, the purpose of the current study was to examine the impact of moderate intensity aerobic exercise training on fat mass, blood lipid profiles, fibrinolytic activity, and NO levels in high-fat-diet induced rats. The body weight, fat mass, blood lipid profiles, fibrinolytic activity, and nitrite/nitrate were measured pre- and postexercise (10 weeks) training. The body weight and fat mass reduced significantly in the exercise (EX) group compared to the control (CON) group. Blood lipid profiles and low-density lipoprotein were unchanged in the EX group compared to the CON group. However, triglyceride and free fatty acid were significantly lower in the EX group compared to the CON group, and high-density lipoprotein was significantly greater in the EX group compared to the CON group. In addition, fibrinolytic activity and nitrite/nitrate were significantly greater in the EX compared to the CON group. These results suggest that 10 weeks of the moderated intensity aerobic exercise training improves blood lipid profiles, fibrinolytic activity, and the nitrite/nitrate ratio, which may improve vascular health and reduce obesity-related cardiovascular disease risks in high-fat- diet induced rats