Spin polarization amplification within nonmagnetic semiconductors at room temperature

We demonstrate theoretically that the spin polarization of current can be electrically amplified within nonmagnetic semiconductors by exploiting the fact the spin current, compared to the charge current, is weakly perturbed by electric driving forces. As a specific example, we consider a T-shaped current branching geometry made entirely of a nonmagnetic semiconductor, where the current is injected into one of the branches (input branch) and splits into the other two branches (output branches). We show that when the input current has a moderate spin polarization, the spin polarization in one of the output branches can be higher than the spin polarization in the input branch and may reach 100% when the relative magnitudes of current-driving electric fields in the two output branches are properly tuned. The proposed amplification scheme does not use ferromagnets or magnetic fields, and does not require low temperature operation, providing an efficient way to generate a highly spin polarized current in nonmagnetic semiconductors at room temperature.Comment: 11 pages, 2 figures, to appear in Phys. Rev.

Current-Induced Magnetic Domain-Wall Motion by Spin Transfer Torque: Collective Coordinate Approach with Domain-Wall Width Variation

The spin transfer torque generated by a spin-polarized current can induce the shift of the magnetic domain-wall position. In this work, we study theoretically the current-induced domain-wall motion by using the collective coordinate approach [Gen Tatara and Hiroshi Kohno, Phys. Rev. Lett. 92, 86601 (2004)]. The approach is extended to include not only the domain-wall position and the polarization angle changes but also the domain-wall width variation. It is demonstrated that the width variation affects the critical current.Comment: 13 pages, 3 figure

On SS-nn-absorbing ideals

Let $R$ be a commutative ring with identity, $S$ a multiplicative subset of $R$ and $I$ an ideal of $R$ disjoint from $S$. In this paper, we introduce the notion of an $S$-$n$-absorbing ideal which is a generalization of both the $S$-prime ideals and $n$-absorbing ideals. Moreover, we investigate the basic properties, quotient extension, existence and amalgamation of $S$-$n$-absorbing ideals.Comment: 18page

Current-induced domain wall motion in a nanowire with perpendicular magnetic anisotropy

We study theoretically the current-induced magnetic domain wall motion in a metallic nanowire with perpendicular magnetic anisotropy. The anisotropy can reduce the critical current density of the domain wall motion. We explain the reduction mechanism and identify the maximal reduction conditions. This result facilitates both fundamental studies and device applications of the current- induced domain wall motion

New Approach of Anti-VEGF Agents for Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is the leading cause of visual loss in older population. Angiogenesis is an important factor associated with the development of CNV due to AMD. Treatment of CNV with intravitreal anti-VEGF monotherapy is currently the standard of care. However, not all patients respond to monotherapy, and modified anti-VEGF treatment regimen and combination therapy may target reducing treatment frequency or improving visual outcome. This paper reviews the many clinical trials that have been performed utilizing several treatment regimens. While many trials have shown that this variable therapy is justifiable, further study is required to determine correct regimens and dosage

Real-Time Test-Bed System Development Using Power Hardware-in-the-Loop (PHIL) Simulation Technique for Reliability Test of DC Nano Grid

Since various power sources such as renewable energy and energy storage systems (ESSs) are connected to the DC grid, the reliability of the grid system is significant. However, the configuration of an actual DC grids for testing the reliability of the grid system is inconvenient, expensive and dangerous. In this paper, a test-bed system made up of a 20-kW DC nano grid and a control algorithm considering an external grid based on Power Hardware-in-the-Loop (PHIL) simulation are proposed to demonstrate the reliability of the DC grid. Using the PHIL simulation technique, target grids can be safely implemented with laboratory-level instruments and simulated by real-time simulators, which emulates grid operations that are similar to the actual grid. In addition, using the proposed control algorithm, the operations of grid-connected converters are demonstrated according to the grid-connected or islanding modes. Finally, the reliability of the simulated DC nano grid and the effectiveness of the grid-connected converter are verified using the PHIL simulation system with 3-kW prototype converters

Strategy for Improving Efficiency of Supply Chain Quality Management in Buyer-Supplier Dyads: The Suppliers’ Perspective

This study analyzes the efficiency of supply chain quality management (SCQM) by grouping buyers and suppliers and conducting an empirical analysis of aspects affecting SCQM efficiency from the supplier’s perspective. Two stages of data analysis were conducted: (1) classify buyer and supplier efficiency by means of data envelopment analysis (DEA) and sort the data results into a 2×2 matrix and (2) conduct a statistical analysis to verify influential aspects. The results depict the average value of Group I to be higher than that of Group II, while the average value of Group IV was found to be much lower than that of Group III. In addition, specific aspects have a significant impact on certain groups: Groups I and II are affected by infrastructure, delivery of quality, talent development, and risk management in that order; Groups II and III are likewise influenced by risk management, talent development, and delivery of quality, whereas Groups III and IV are influenced by talent development, delivery of quality, and risk management in that order

BSART (Broadcasting with Selected Acknowledgements and Repeat Transmissions) for Reliable and Low-costed Broadcasting in the Mobile Ad-hoc Network

Abstract. In this paper, we suggest enhanced broadcasting method, named 'BSART(Broadcasting with Selected Acknowledgement and Repeat Transmissions)' which reduces broadcast storm and ACK implosion on the mobile ad-hoc network with switched beam antenna elements that can enable bidirectional communication. To reduce broadcast storm, we uses DPDP(Directional Partial Dominant Pruning) method, too. To control ACK implosion problem rising on reliable transmission based on ACK, in case of the number of nodes that required message reception is more than throughput, each nodes retransmit messages constant times without ACK which considering message transmission success probability through related antenna elements(Rmethod). Otherwise, the number of message reception nodes is less than throughput, each node verify message reception with ACK with these antenna elements(A-method). In this paper, we suggest mixed R-/A-method. This method not only can control the number of message transmitting nodes, can manage the number of ACK for each antenna elements. By simulations, we proved that our method provides higher transmission rate than legacy system, reduces broadcast messages and ACKs