3,101 research outputs found
The jamming transition and new percolation universality classes in particulate systems with attraction
We numerically study the jamming transition in particulate systems with
attraction by investigating their mechanical response at zero temperature. We
find three regimes of mechanical behavior separated by two critical
transitions--connectivity and rigidity percolation. The transitions belong to
different universality classes than their lattice counterparts, due to force
balance constraints. We also find that these transitions are unchanged at low
temperatures and resemble gelation transitions in experiments on colloidal and
silica gels.Comment: 4 pages, 2 figures, 2 table
Numerical analysis of tsunami flow around coastal dyke
Japan has a long stretch of coastal dykes along its shoreline to protect against storm surges, tsunamis and high wind waves. The 2011 Tohoku Earthquake and Tsunami caused serious damage to these coastal dykes. To improve the coastal dykes along the damaged coast and also to reconsider tsunami risks in other parts of the Japanese\ud
coast, it is important to understand the effect that a tsunami can have on a coastal dyke. The present paper thus aims to analyze a tsunami flow around a coastal dyke using a LES numerical model. To simulate both an impact phase and an overtopping phase of a tsunami flow, which were observed in the 2011 tsunami, a dam break flow and a pump flow were used to generate a tsunami-like flow in the numerical model. Based on the numerical results, the pressure and the velocity field around a coastal dyke were ascertained. These effects were considered to have a big influence on the dike failure in the 2011 tsunami, and thus it is recommended that the design of countermeasures should include a calculation of both of these parameters
Universal charge transport of the Mn oxides in the high temperature limit
We have found that various Mn oxides have the universal resistivity and
thermopower in the high temperature limit. The resistivities and thermopowers
of all the samples go toward constant values of 71 mcm and
3 V/K, which are independent of carrier density and crystal
structures. We propose that the electric conduction occurs in a highly
localized way in the high temperature limit, where the exchange of entropy and
charge occurs in the neighboring Mn and Mn ions.Comment: 4 pages, 4 eps figures, to be published in J. Appl. Phy
Investigation of Microstructure of Cementitious Materials Exposed to High Temperature by Non-destructive Integrated CT-XRD Method
Severe accident occurred in 2011 at the Fukushima Daiichi nuclear power plant and it can be assumed that the concrete building was exposed to high temperatures environment for a long time due to loss of the cooling function of the nuclear reactor. In order to prepare for the best scenario in the decommission plan, it should be first needed to clarify and evaluate the level of damage and deterioration of the contaminated concrete. To solve this problem, experiments were conducted for cementitious materials with the maximum temperature of 400 or 1000 degrees Celsius with durations of up to 2 hours. Subsequent results were evaluated microscopically. In this research, authors have employed a Non-Destructive Integrated CT-XRD Method using synchrotron white X-ray. The unique feature of this method is that both CT for measuring internal structure and XRD for identifying crystal structure can be performed on the same specimen at the same time. Therefore, in addition to other measurements such as the Thin film X-ray diffraction technique, the application of this method is expected to bring an interesting exploration with regard to the physical and chemical alteration of the concrete that was endured by high temperatures
Mitochondrial haplogroups associated with elite Japanese athlete status
Purpose It has been hypothesised that certain mitochondrial haplogroups, which are defined by the presence of a characteristic cluster of tightly linked mitochondrial DNA polymorphisms, would be associated with elite Japanese athlete status. To examine this hypothesis, the frequencies of mitochondrial haplogroups found in elite Japanese athletes were compared with those in the general Japanese population. Methods Subjects comprised 139 Olympic athletes (79 endurance/middle-power athletes (EMA), 60 sprint/power athletes (SPA)) and 672 controls (CON). Two mitochondrial DNA fragments containing the hypervariable sequence I (m16024-m16383) of the major non-coding region and the polymorphic site at m. 5178C>A within the NADH dehydrogenase subunit 2 gene were sequenced, and subjects were classified into 12 major mitochondrial haplogroups (ie, F, B, A, N9a, N9b, M7a, M7b, M*, G2, G1, D5 or D4). The mitochondrial haplogroup frequency differences among EMA, SPA and CON were then examined. Results EMA showed an excess of haplogroup G1 (OR 2.52, 95% CI 1.05 to 6.02, p=0.032), with 8.9% compared with 3.7% in CON, whereas SPA displayed a greater proportion of haplogroup F (OR 2.79, 95% CI 1.28 to 6.07, p=0.007), with 15.0% compared with 6.0% in CON. Conclusions The results suggest that mitochondrial haplogroups G1 and F are associated with elite EMA and SPA status in Japanese athletes, respectivel
Markov marginal problems and their applications to Markov optimal control
In this paper we discuss a class of Markov marginal problems (MMP). By MMP, we mean the problem to construct a Markov process with given (marginal) constraints on the path space. As an application we consider Markov optimal control problems
Monge's problem with a quadratic cost by the zero-noise limit h-pass processes
We study the asymptotic behavior, in the zero noise limit, of solutions to Schrodinger's functional equations and that of h-pass processes, and give a new proof of the existence of the minimizer of Monge's problem with a quadratic cost
Large Deviations and Centrallimit Theorems for Eyraud-Farlie-Gumbel-Morgenstern Processes
Let {Xn} 1 be a Eyraud-Farlie-Gumbel-Morgenstern process. Put Sn = E =l Xk. In this paper we prove the large deviations theorem for Bn/n, and the central limit theorem for Bn/n112 , as n - ∞
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