两种数字生命的Swarm仿真研究

数字生命的概念是托马斯·雷最早在计算机上模拟实验提出的,以此为指导,介绍了复杂适应系统、Agent建模等理论知识,利用Swarm仿真平台构建了两种异类数字生命及共同生存的环境,模拟自然界生命体最基础的繁殖歼灭等生命现象,通过可视化窗口观察生命体个体及群体间的交互行为,得到结果的不可测性和突现性,实现了两种数字生命的Swarm仿真。     

删失试验寿命的贝叶斯生存极值回归模型

针对删失寿命试验数据缺少随机变量尾部分布和常规删失数据分析对长寿命区高可靠度估计不准确的问题,构建了一个结构元件寿命分布的贝叶斯生存极值回归模型。运用MCMC方法与Gibbs抽样获得参数后验分布的基本原理,借助数据仿真说明了利用WinBUGS软件包进行建模分析的过程,证明了该模型在删失试验中的直观性和有效性。研究结果表明:利用Gibbs抽样进行模拟分析,能很方便地得到模型参数的相关估计。     

加速寿命试验中多应力加速模型综述

针对加速寿命试验发展的瓶颈问题——加速模型的确定,将国际上已提出的具有代表性的多应力加速模型进行了具体介绍和分析。从模型提出的方法及其适用性出发,特别讨论了Fallou等人提出的适用于电子绝缘器件的各种温度电应力加速模型,以及由美国马里兰大学Barker等人提出的适用于简单印制电路板的温度振动应力加速模型。最后通过各种模型的对比以及模型与实际情况间差距的分析,指出了现有多应力加速模型存在的缺陷及其发展趋势。     

糖类遗传与生命起源

从遗传学角度探讨了糖类与生命起源，讨论了遗传学上的再认识，提出糖类在遗传学上扮演着重要、核心的角色、糖类是生命起源物质，基因是糖类衍生物。生命诞生过程可能是：先有糖类、然后有氨基酸和碱基；磷酸及其盐类既是生命物质的组成部分、也是催化剂，阳光或地热为能源，于是诞生了基因。生命体是分子相互作用、有序组合、自我调控的耗散体系。     

近五年来中国现代科学家研究述评

科学家研究是中国现代科技史研究的进路和重要内容。本文以近五年来六种期刊发表的科学家研究论文为例,对学界对此问题的研究做简单述评,并认为应该加强科学思想史的研究。     

Observations of water-flea Daphnia magna and avian fecalia in rock pools: is traditional natural history reporting still relevant for science?

Unexpected observation of freshwater invertebrate Daphnia magna in temporary rock pools on a small island off the Norwegian Atlantic coast confirms colonising ability, mediated through avian dispersal. Robust diapausal eggs of D. magna pass the gut of migrating geese and subsequently hatch in environments where such waterfowl forage and rest along migrating routes. The incubation experiment demonstrates that decomposing fecalia of geese constitute sufficient feed to support developing populations of D. magna in experimental oligotrophic conditions. The findings also show that D. magna is highly adapted for colonisation of temporary pools north of the Arctic Polar Circle, with excellent tolerance to low temperatures. Discussion part I relates the findings to published evidence on avian transport of invertebrate propagules, such as correlations between migration patterns of waterfowl and geographical patterns of aquatic invertebrate diversity. Discussion part II reflects on academic cultures, epistemological aspects of natural history reporting, the presence of a whale cadaver as an ecological indicator and the relevance of simple observation as a starting point for further discourse.     

Kant on anatomy and the status of the life sciences

This paper contributes to recent interest in Kant's engagement with the life sciences by focusing on one corner of those sciences that has received comparatively little attention: physical and comparative anatomy. By attending to remarks spread across Kant's writings, we gain some insight into Kant's understanding of the disciplinary limitations but also the methodological sophistication of the study of anatomy and physiology. Insofar as Kant highlights anatomy as a paradigmatic science guided by the principle of teleology in the Critique of the Power of Judgment, a more careful study of Kant's discussions of anatomy promises to illuminate some of the obscurities of that text and of his understanding of the life sciences more generally. In the end, it is argued, Kant's ambivalence with regard to anatomy gives way to a pessimistic conclusion about the possibility that anatomy, natural history, and, by extension, the life sciences more generally might one day become true natural sciences.     

拟真世界与客体策略——鲍德里亚的技术决定论及启示

鲍德里亚的后现代理论是一种典型的技术决定论,他构建了一个由模型、符码所生成的拟真世界,在那里DNA和0/1数字具有了本体论意义。在高科技的世界里,主体失去了丰富而多样的存在,成为技术的创造物和附属物。伴随着主体衰落而产生的是客体的兴盛与强大,客体世界开始控制并主宰着人类社会的运行。鲍德里亚由此提出一种消极的宿命论,即客体系统自身发展到完美、极致,并在顶点上自动内爆、反转。鲍德里亚的理论对于我们反思日益频繁的自然灾害和技术危机、对于重新考量人与自然、技术之间关系提供了有益的启示。     

Mortality effects of temperature changes in the United Kingdom

Temperature changes are known to affect the social and environmental determinants of health in various ways. Consequently, excess deaths as a result of extreme weather conditions may increase over the coming decades because of climate change. In this paper, the relationship between trends in mortality and trends in temperature change (as a proxy) is investigated using annual data and for specified (warm and cold) periods during the year in the UK. A thoughtful statistical analysis is implemented and a new stochastic, central mortality rate model is proposed. The new model encompasses the good features of the Lee and Carter (Journal of the American Statistical Association, 1992, 87: 659–671) model and its recent extensions, and for the very first time includes an exogenous factor which is a temperature‐related factor. The new model is shown to provide a significantly better‐fitting performance and more interpretable forecasts. An illustrative example of pricing a life insurance product is provided and discussed.     

From aether impulse to QED: Sommerfeld and the Bremsstrahlen theory

The radiation that is due to the braking of charged particles has been in the focus of theoretical physics since the discovery of X-rays by the end of the 19th century. The impact of cathode rays in the anti-cathode of an X-ray tube that resulted in the production of X-rays led to the view that X-rays are aether impulses spreading from the site of the impact. In 1909, Arnold Sommerfeld calculated from Maxwell׳s equations the angular distribution of electromagnetic radiation due to the braking of electrons. He thereby coined the notion of “Bremsstrahlen.” In 1923, Hendrik A. Kramers provided a quantum theoretical explanation of this process by means of Bohr׳s correspondence principle. With the advent of quantum mechanics the theory of bremsstrahlung became a target of opportunity for theorists like Yoshikatsu Sugiura, Robert Oppenheimer, and–again–Sommerfeld, who presented in 1931 a comprehensive treatise on this subject. Throughout the 1930s, Sommerfeld׳s disciples in Munich and elsewhere extended and improved the bremsstrahlen theory. Hans Bethe and Walter Heitler, in particular, in 1934 presented a theory that was later regarded as “the most important achievement of QED in the 1930s” (Freeman Dyson). From a historical perspective the bremsstrahlen problem may be regarded as a probe for the evolution of theories in response to revolutionary changes in the underlying principles.