Last Passage Time Statistics for Barrier-Crossing Processes

A concept of mean last passage time at the saddle point is proposed in order to compute both the lifetime and the escape rate of a particle in a metastable potential, where the backstreaming across the saddle point is taken into account. It is shown that the mean oscillating time around the saddle point is the longest one among all the time scales at high temperatures and the inverse of the mean last passage time at the saddle point is more close to the steady escape rate.     

平均最后通过时间和热核裂变速率

提出利用平均最后通过鞍点时间计算热核裂变速率,结果表明平均最后通过鞍点时间的倒数比平均首次通过断点时间的倒数更接近朗之万数值模拟值. The mean last passage time is introduced to instead of the mean first passage time for studying the decay of an induced-fissioning system. The stationary fission rate determined by the inverse of mean last passage time across the saddle point is agreement with the resulting rate of Langevin simulation and better than that of mean first passage time arriving at the scission point.     

The Vacuum as Ether in the Last Century

In this paper we review the evolution of the concept of vacuum according to different theories formulated in the last century, like Quantum Mechanics, Quantum Electrodynamics, Quantum Chromodynamics in Particle Physics and Cosmology. In all these theories a metastable vacuum state is considered which transforms from one state to another according to the energy taken into consideration. It is a fluid made up by matter and radiation present in the whole Universe, which may be identified with a modern definition of ether     

微信服务平台的设计及在办公中的应用

由于电脑办公对地点、设备等要求带来的不便,所以对微信办公进行了研究,提出了基于微信公众平台的高校办公流程。采用Linux php mysql作为开发平台,利用微信公众平台开放接口实现整个过程。以校园信息化服务系统为例,阐述了该系统的办公流程、设计方法、核心技术,达到普通用户可通过微信客户端向学校各部门提出建议,管理员通过微信绑定身份后可实现信息分类、回复等办公操作的目的。借助微信公众平台实现智能终端办公,有助于实时交互、提高办公效率、简化办公操作,与此同时,也对此类微信办公开发具有借鉴意义。