Strange Form Factors of Baryons

The strange magnetic form factor of proton is calculated in a model independent way to confirm the recent experimental result of the SAMPLE Collaboration. We consider a set of six inertia parameters to realize the magnetic moments of the baryon octet. We show that the strange form factor of proton is a positive quantity, i.e. +0.37 n.m.. Its positiveness is analyzed in terms of the vacuum fluctuation coupled to the vector current along the strangeness direction.Comment: 10 pages, 1 figure, Latex, revised versio

Formation of regular nanoscale undulations on a thin polymer film imprinted by a soft mold

We observed the formation of regular nanoscale undulations on a polystyrene film when imprinted by a soft poly(dimethylsiloxane) mold above the polymer's glass transition temperature. The shape of the wave was reminiscent of a buckling wave frequently observed for a metal film supported on an elastomeric substrate. We derived a simple theoretical model based on an anisotropic buckling of the polymer film rigidly bound to a substrate, which agrees well with the experiment.This work was supported by the Micro Thermal Research Center of Seoul National University

4-Hydroxy­phenyl 4-fluoro­benzoate

In the title compound, C13H9FO3, the dihedral angle between the two benzene rings is 59.86 (4)°. In the crystal, inter­molecular O—H⋯H hydrogen bonds lead to molecular chains propagating in [010]

Controlling Ferromagnetic Easy Axis in a Layered MoS2 Single Crystal

We report the effective methods to induce weak ferromagnetism in pristine MoS2 persisting up to room temperature with the improved transport property, which would lead to new spintronics devices. The hydrogenation of MoS2 by heating at 300 degrees C for 1 h leads to the easy axis out of plane, while the irradiation of proton with a dose of 1 x 10(13) P/cm(2) leads to the easy axis in plane. The theoretical modeling supports such magnetic easy axes.open16

Controlling ferromagnetic easy axis in a layered MoS2 single crystal

We report the effective methods to induce weak ferromagnetism in pristine MoS2 persisting up to room temperature with the improved transport property, which would lead to new spintronics devices. The hydrogenation of MoS2 by heating at 300 degrees C for 1 h leads to the easy axis out of plane, while the irradiation of proton with a dose of 1 x 10(13) P/cm(2) leads to the easy axis in plane. The theoretical modeling supports such magnetic easy axes.open116160Nsciescopu

An appraisal of a column-generation-based algorithm for centralized train-conflict resolution on a metropolitan railway network

In practice, a train-conflict resolution is decentralized around dispatchers each of whom controls a few segments in a global railway network with her rule-of-thumb to operational data. Conceptually, the global sub-optimality or infeasibility of the decentralized system is resolved by a network controller who coordinates the dispatchers and train operators at the lower layers on a real-time basis. However, such notion of a multi-layer system cannot be effectual unless the top layer is able to provide a global solution soon enough for the dynamic lower layers to adapt in a seamless manner. Unfortunately, a train-conflict resolution problem is NP-hard as formally established in this paper and an effective solution method traded off between computation time and solution quality has been lacking in literature. Thus, we propose a column-generation-based algorithm that exploits the separability of the problem. A key ingredient of the algorithm is an efficient heuristic for the pricing subproblem for column generation. Tested on the real data from the Seoul metropolitan railway network, the algorithm provides near-optimal conflict-free timetables in a few seconds for most cases. The performance of the proposed algorithm is compared to the ones of the previous MIP-based heuristic by Törnquist and Persson (2007) and the priority-based heuristic by Sahin (1999)

An appraisal of a column-generation-based algorithm for centralized train-conflict resolution on a metropolitan railway network

In practice, a train-conflict resolution is decentralized around dispatchers each of whom controls a few segments in a global railway network with her rule-of-thumb to operational data. Conceptually, the global sub-optimality or infeasibility of the decentralized system is resolved by a network controller who coordinates the dispatchers and train operators at the lower layers on a real-time basis. However, such notion of a multi-layer system cannot be effectual unless the top layer is able to provide a global solution soon enough for the dynamic lower layers to adapt in a seamless manner. Unfortunately, a train-conflict resolution problem is NP-hard as formally established in this paper and an effective solution method traded off between computation time and solution quality has been lacking in literature. Thus, we propose a column-generation-based algorithm that exploits the separability of the problem. A key ingredient of the algorithm is an efficient heuristic for the pricing subproblem for column generation. Tested on the real data from the Seoul metropolitan railway network, the algorithm provides near-optimal conflict-free timetables in a few seconds for most cases. The performance of the proposed algorithm is compared to the ones of the previous MIP-based heuristic by Törnquist and Persson (2007) and the priority-based heuristic by Sahin (1999).Train-conflict resolution NP-hardness Column generation Fix-and-regenerate