Dilatancy of frictional granular materials under oscillatory shear with constant pressure

We perform numerical simulations of a two-dimensional frictional granular system under oscillatory shear confined by constant pressure. We found that the system undergoes dilatancy as the strain increases. We confirmed that compaction also takes place at an intermediate strain amplitude for a small mutual friction coefficient between particles. We also found that compaction depends on the confinement pressure while dilatancy little depends on the pressure.Comment: 4 pages, 4 figure

Who Uses Free Trade Agreements?

It is noted that utilization of ASEAN Free Trade Agreements (FTAs) is low by international standards. In order to clarify the reasons for such low utilization, this paper investigates what kinds of Japanese affiliates in ASEAN are more likely to use FTAs in their exporting, by employing unique affiliate-level data. Our findings are as follows. First, the larger the affiliate is, or the more diversified the origins of its procurements, the more likely it is to utilize an FTA scheme in its exporting. Second, affiliates that export actively to countries with higher general tariffs are more likely to use FTAs. Third, there are clear differences in FTA utilization depending affiliates, locations and sectors.

Who Uses FTAs?

It is noted that utilization of AFTA is low by international standards. In order to clarify the reasons for such low utilization, this paper investigates what kinds of Japanese affiliates in ASEAN are more likely to use FTAs in their exporting, by employing unique affiliate-level data. Our findings are as follow. First, the larger the affiliate is, or the more diversified its procurements’ origins are, the more likely it is to utilize an FTA scheme in its exporting. Second, affiliates exporting actively to developing countries are more likely to use FTAs than those exporting to developed countries. Third, there are clear differences in FTA utilization depending on affiliates’ locations and sectors. These results afford a clue to the reasons for the low FTA utilization in East Asia.FTA, Micro data, ASEAN, International trade, Regional economic cooperation, International economic integration

Who Uses FTAs?

It is noted that utilization of AFTA is low by international standards. In order to clarify thereasons for such low utilization, this paper investigates what kinds of Japanese affiliates inASEAN are more likely to use FTAs in their exporting, by employing unique affiliate-level data.Our findings are as follow. First, the larger the affiliate is, or the more diversified itsprocurements’ origins are, the more likely it is to utilize an FTA scheme in its exporting. Second,affiliates exporting actively to developing countries are more likely to use FTAs than thoseexporting to developed countries. Third, there are clear differences in FTA utilization dependingon affiliates’ locations and sectors. These results afford a clue to the reasons for the low FTAutilization in East Asia

Eigenvalue analysis of stress-strain curve of two-dimensional amorphous solids of dispersed frictional grains with finite shear strain

The stress-strain curve of two-dimensional frictional dispersed grains interacting with a harmonic potential without considering the dynamical slip under a finite strain is determined by using eigenvalue analysis of the Hessian matrix. After the configuration of grains is obtained, the stress-strain curve based on the eigenvalue analysis is in almost perfect agreement with that obtained by the simulation, even if there are plastic deformations caused by stress avalanches. Unlike the naive expectation, the eigenvalues in our model do not indicate any precursors to the stress-drop events.Comment: 22 pages, 16 figures. arXiv admin note: text overlap with arXiv:2207.0663

Theory of rigidity and density of states of two-dimensional amorphous solids of dispersed frictional grains in the linear response regime

Using the Jacobian matrix, we theoretically determine the rigidity of two-dimensional amorphous solids consisting of frictional grains in the linear response to an infinitesimal strain, in which we ignore the dynamical friction caused by the slip processes of contact points. The theoretical rigidity agrees with that obtained by molecular dynamics simulations. We confirm that the rigidity is smoothly connected to the value in the frictionless limit. We find that there are two modes in the density of states for sufficiently small $k_{T}/k_{N}$, which is the ratio of the tangential to normal stiffness. Rotational modes exist at low frequencies or small eigenvalues, whereas translational modes exist at high frequencies or large eigenvalues. The location of the rotational band shifts to the high-frequency region with an increase in $k_{T}/k_{N}$ and becomes indistinguishable from the translational band for large $k_{T}/k_{N}$. The rigidity determined by the translational modes agrees with that obtained by the molecular dynamics simulations, whereas the contribution of the rotational modes is almost zero for small $k_{T}/k_{N}$.Comment: 10 pages, 15 figure