Relativistic mean-field approximation with density-dependent screening meson masses in nuclear matter

The Debye screening masses of the $\sigma$, $\omega$ and neutral $\rho$ mesons and the photon are calculated in the relativistic mean-field approximation. As the density of the nucleon increases, all the screening masses of mesons increase. It shows a different result with Brown-Rho scaling, which implies a reduction in the mass of all the mesons in the nuclear matter except the pion. Replacing the masses of the mesons with their corresponding screening masses in Walecka-1 model, five saturation properties of the nuclear matter are fixed reasonably, and then a density-dependent relativistic mean-field model is proposed without introducing the non-linear self-coupling terms of mesons.Comment: 14 pages, 3 figures, REVTEX4, Accepted for publication in Int. J. Mod. Phys.

Broadband opto-mechanical phase shifter for photonic integrated circuits

A broadband opto-mechanical phase shifter for photonic integrated circuits is proposed and numerically investigated. The structure consists of a mode-carrying waveguide and a deformable non-mode-carrying nanostring, which are parallel with each other. Utilizing the optical gradient force between them, the nanostring can be deflected. Thus the effective refractive indices of the waveguide is changed with the deformation, and further causes a phase shift. The phase shift under different geometry sizes, launched powers and boundary conditions are calculated and the dynamical properties as well as the thermal noise's effect are also discussed. It is demonstrated that a $\pi$ phase shift can be realized with only about 0.64 mW launched power and 50 $\mu m$ long nanostring. The proposed phase shifter may find potential usage in future investigation of photonic integrated circuits

Study on Complex Products Job-shop Scheduling System Based on MES

Various random disturbances that happen in the process of complex products (ship) production cannot feedback timely, and the plans of job-shop operation are too rough to instruct job-shop production. The purpose of this study is to solve the problems above, help the course of complex products (ship) job-shop production runs orderly and efficiently, and improve the job-shop on-site management level. In this paper, we proposed complex products job-shop scheduling system based on MES. The system adopts six-level, refined plan and scheduling mechanism. Its key part is the job-shop scheduling model with man-machine coordinated mechanism. What’s more, an improved Genetic Algorithm based on TOC is proposed to make the optimized algorithm module of the system more scientific and effective. Key words: Complex Products; MES; Job-shop Scheduling System; Man-machine Coordinated Mechanism; Genetic Algorithm Résumé: Diverses perturbations qui se produisent au hasard dans le processus de production des produits complexes (navire) ne peuvent pas être apperçues en temps opportun, et les plans de l'opération des ateliers sont trop approximatifs pour guider la production. Le but de cette étude consiste à résoudre les problèmes ci-dessus, rendre le cours de la production des produits complexes (ship) dans les ateliers ordonné et efficace et améliorer le niveau de gestion sur place. Dans cet article, nous avons proposé le système de planning des ateliers de produits complexes basé sur MES. Le système contient six niveaux de programmation raffinée et de mécanismes de planning. Son élément essentiel est le modèle de programmation avec les mécanismes de coordination homme-machine. De plus, un algorithme génétique amélioré basé sur TOC est également proposé de rendre le module de l'algorithme du système optimisé plus scientifique et efficace. Mots-clés: produits complexes; MES; système de planning des ateliers; mécanismes de coordination homme-machine; algorithme génétique 摘要：針對目前複雜產品（船舶）生產過程中所出現的各種隨機擾動不能得到及時回饋，以及車間作業計畫粗略難以直接指導車間生產的現狀，本文提出基於 MES的複雜產品車間作業調度系統。該系統採用逐層細化的五級計畫與調度機制，以人機協同的車間作業調度模型為核心，通過改進基於 TOC的遺傳演算法，使系統的演算法模組優化性能更具有科學性和操作性。該系統有助於實現複雜產品（船舶）車間生產過程的有序運作，從而提高生產車間的現場管理水準。 關鍵字：複雜產品； MES；車間作業調度；人機協同；遺傳演算

Effective photon mass in nuclear matter and finite nuclei

Electromagnetic field in nuclear matter and nuclei are studied. In the nuclear matter, because the expectation value of the electric charge density operator is not zero, different in vacuum, the U(1) local gauge symmetry of electric charge is spontaneously broken, and consequently, the photon gains an effective mass through the Higgs mechanism. An alternative way to study the effective mass of photon is to calculate the self-energy of photon perturbatively. It shows that the effective mass of photon is about $5.42MeV$ in the symmetric nuclear matter at the saturation density $\rho_0 = 0.16fm^{-3}$ and about $2.0MeV$ at the surface of ${}^{238}U$. It seems that the two-body decay of a massive photon causes the sharp lines of electron-positron pairs in the low energy heavy ion collision experiments of ${}^{238}U+{}^{232}Th$ .Comment: 10 pages, 2 figures, 1 table, REVTEX4, submitted to Int. J. Mod. Phys.

Immune Responses Following Mouse Peripheral Nerve Xenotransplantation in Rats

Xenotransplantation offers a potentially unlimited source for tissues and organs for transplantation, but the strong xenoimmune responses pose a major obstacle to its application in the clinic. In this study, we investigate the rejection of mouse peripheral nerve xenografts in rats. Severe intragraft mononuclear cell infiltration, graft distension, and necrosis were detected in the recipients as early as 2 weeks after mouse nerve xenotransplantation. The number of axons in xenografts reduced progressively and became almost undetectable at week 8. However, mouse nerve xenotransplantation only led to a transient and moderate increase in the production of Th1 cytokines, including IL-2, IFN-γ, and TNF-α. The data implicate that cellular immune responses play a critical role in nerve xenograft rejection but that further identification of the major effector cells mediating the rejection is required for developing effective means to prevent peripheral nerve xenograft rejection

Simulation of centrifugal pumps based on MPS solver

In this article, a three dimensional full-scale centrifugal pump is, for the first time, simulated using the moving particle semi-implicit method(MPS). The genetic smooth wall boundary(GSW) is used and extended to three dimension to deal with the complicated wall shape and thin blades in turbo-machines. The non-surface detection technique(NSD) based on conceptual particles is combined with this wall model to avoid the loss of particle number density near wall boundaries. A local wall particle refinement method is developed. Fine particles and coarse particles are applied to curved surface and flat surface respectively so as to reduce the computational cost while maintain the high discretization precision. The fully developed velocity inflow and pressure outflow boundary conditions are proposed. Three typical cases including hydrostatic cases with complicated geometry, flows over a two-dimensional backward-facing step, and flows in a three-dimensional tube are tested to verify the proposed models. This paper constructs a framework for the simulation of incompressible fluid machines, in which 3D complex revolving bodies can be integrally discretized and interactions between the stator and rotor can be integrally solved within a single coordinate. This paper provides a particle-based solver for incompressible fluid machinery and has the potential to study its inner flow with multiphase or phase change

Movable Fiber-Integrated Hybrid Plasmonic Waveguide on Metal Film

A waveguide structure consisting of a tapered nanofiber on a metal film is proposed and analyzed to support highly localized hybrid plasmonic modes. The hybrid plasmonic mode can be efficiently excited through the in-line tapered fiber based on adiabatic conversion and collected by the same fiber, which is very convenient in the experiment. Due to the ultrasmall mode area of plasmonic mode, the local electromagnetic field is greatly enhanced in this movable waveguide, which is potential for enhanced coherence light emitter interactions, such as waveguide quantum electrodynamics, single emitter spectrum and nonlinear optics