一类Boltzmann & Darwin混合寻优策略的收敛特性研究

基于文［１］提出的求解组合最优化问题的Ｂｏｌｔｚｍａｎｎ＆Ｄａｒｗｉｎ混合寻优策略，本文进一步分析研究了Ｂｏｌｔｚｍａｎｎ＆Ｄａｒｗｉｎ混合寻优策略非时齐情形下的收敛特性，包括全局收敛性和收敛速度。结果表明，Ｂｏｌｔｚｍａｎｎ＆Ｄａｒｗｉｎ混合寻优策略的收敛特性优于模拟退火（ｓｉｍ－ｕｌａｔｅｄ ａｎｎｅａｌｉｎｇ）方法的收敛特性。     

利用运动强度自适应传输视频内容

在异构的网络环境下,如何自适应地传输满足多种终端设备和不同用户需求的视频内容具有重要的意义.以达尔文流媒体服务器为实验平台,提出一套基于运动强度的视频自适应传输策略.在服务器端通过检测丢包率来控制发送速率等级,避免网络拥塞,并采取一定策略消除因丢帧而产生的马赛克;在自适应策略中加入了运动强度信息,针对不同的运动强度级别进行不同的处理,使得综合视频质量得到提高.实验结果表明,文中的自适应策略不仅可以避免网络拥塞,而且可以改善视频播放质量.     

Darwin Streaming server的研究与应用

分析了Darwin streaming server(DSS)的架构和核心流程；讨论了Darwin streaming servcr的二次开发接口：nlodule；最后给出了一个用户认证的二次开发模块。     

The Poetics of the Island of Vessels

Since 2000, Neil Spiller has been engaged on a ‘long project’: a series of hundreds of drawings that through a potent mix of cyborgian fantasy and Surrealism, imbued with poetry and biotechnology, evoke a psycho-geographical island inhabited by an irascible alter ego, ‘The Professor’. Spiller seeks out in this work ‘an unusual and startling architecture’ that reveals a ‘loving, enigmatic and ragged beauty’.     

Mindfulness and psychological process.

The author reviews the articles in the Special Section on Mindfulness, starting from the assumption that emotions evolved as signaling systems that need to be sensitive to environmental contingencies. Failure to switch off emotion is due to the activation of mental representations of present, past, and future that are created independently of external contingencies. Mindfulness training can be seen as one way to teach people to discriminate such “simulations” from objects and contingencies as they actually are. The articles in this Special Section show how even brief laboratory training can have effects on processing affective stimuli; that long-term meditation practitioners show distinct reactions to pain; that longer meditation training is associated with differences in brain structure; that 8 weeks’ mindfulness practice brings about changes in the way emotion is processed showing that participants can learn to uncouple the sensory, directly experienced self from the “narrative” self; that mindfulness training can affect working memory capacity, and enhance the ability of participants to talk about past crises in a way that enables them to remain specific and yet not be overwhelmed. The implications of these findings for understanding emotion and for further research is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

变形晶体X射线分光性能的数值模拟

通过有限元软件计算同步辐射晶体单色器分光晶体的变形,确定晶体倒格矢的改变量,按变形晶体光学理论预测变形晶体的Darwin宽度,建立一套预测直接水冷却晶体单色器分光性能的方法。算得直接水冷晶体子午方向Darwin宽度展宽为4.12μrad,与采用晶体表面变形倾斜误差计算值(3.89μrad)相比更接近实验值(5.0μrad)。     

离散复杂系统最优化的Darwin&Boltzmann混合策略

离散复杂系统最优化具有广泛的理论和应用背景.基于对现实自然和社会进化中 Darwin过程和不可逆热动力过程的分析,本文提出并构造了一类新的求解离散复杂系统最 优化问题的随机方法--Darwin&Boltzmann混合寻优策略.分析和计算结果表明, Darwin&Boltzmann混合策略求解离散复杂系统最优化问题是有效的且优于模拟退火法. 本文的工作无疑为离散复杂系统最优化的分析和求解提供了新的途径.     

The ‘Annie Hypothesis': Did the Death of His Daughter Cause Darwin to ‘Give up Christianity’?

This article examines one of the most widely believed episodes in the life of Charles Darwin, that the death of his daughter Annie in 1851 caused the end of Darwin's belief in Christianity, and according to some versions, ended his attendance of church on Sundays. This hypothesis, it is argued, is commonly treated as a straightforward true account of Darwin's life, yet there is little or no supporting evidence. Furthermore, we argue, there is sufficient evidence that Darwin's loss of faith occurred before Annie's death.     

网络广播流媒体发布系统

为应对大量用户同时访问网络广播流媒体服务的需求, 流媒体发布系统至关重要. 结合网络广播系统的特点, 设计并实现了一套用于网络广播的流媒体发布系统, 该系统分为媒体流的Relay和流媒体的发布, 媒体流的Relay通过在Darwin Streaming Server添加中继模块, 实现媒体流的中继. 流媒体的发布通过搭建后台管理系统、前端发布平台、终端三部分来实现网络广播业务数据的发布展示. 最后, 通过多终端同时访问发布系统对发布系统进行功能测试, 可实时流畅的的浏览收听网络广播节目.     

一种可扩展的集群流媒体服务器

提出了一种可扩展的适合集群系统的流媒体服务器架构。在这个架构中,整个后台单机服务器是基于Apple公司的DarwinStreamingServer,而在前端开发了一个门户结点和多个中继结点,使整个后台服务器群基本能保持负载平衡、提供给用户高性能的流媒体服务。在外面用户看来整个系统就是一个高性能流媒体服务器。