Maxwell's role in turning the concept of model into the methodology of modeling

This is a contribution towards a history and philosophy of modeling in its early stages in electromagnetism. In 1873, James Clerk Maxwell (1831–1879) hinted at the methodology of modeling at the end of his Treatise on Electricity and Magnetism. We focus on Maxwell's impact on physicists who immediately followed him, specifically Oliver Lodge (1851–1940) and George Francis FitzGerald (1851–1901). We begin with the role that the scientific concept of model played in the late nineteenth century, as assessed by Ludwig Boltzmann (1844–1906). We then discuss the role of hypothesis as a methodology, the appeal to (dynamical) illustration, and the way Maxwell applied model and working model in his studies of electromagnetism. We show that for Maxwell these key terms were kept distinct, but Lodge did not maintain these distinctions and, in this regard, FitzGerald followed Lodge. Notwithstanding Lodge's influence, Fitzgerald modified Maxwell's theory based on the mechanical model he designed, thereby implicitly taking the first step towards modeling. This methodology consists in drawing consequences from the (mechanical) model to the (electrodynamic) theory and modifying the latter in light of the functioning of the former. At the core of our argument is the thesis that it was a methodological novelty to move from the concept of model to the methodology of modeling. The introduction of modeling as a new methodology into physics in the late nineteenth century was a major event which deserves proper recognition.     

谈“十四五”生态保护与绿色发展的生态关系

 从“十四五”保护与发展的生态关系角度，探讨了生态保护与绿色发展的十大生态关系，阐述了生态保护和绿色发展中的一系列有关生态关系的生态智慧及生态技术，并对长江、黄河等流域的生态保护和修复提出了相关建议。     

一类离散时间复杂网络系统的输出同步

利用线性稳定性理论和Lyapunov函数方法,研究了一类离散时间复杂网络系统的输出同步问题,得到了系统输出指数同步的充分性条件,数值算例表明了方法的有效性.     

乡村振兴绩效评价:意义、维度与路径

2018年,中共中央、国务院印发《中国乡村振兴战略规划(2018-2022年)》,全面部署和布局乡村振兴战略.文章基于政府绩效评价的理念和方法,构建乡村振兴绩效评价指标体系,明确评价维度,为实现乡村振兴、城乡融合发展提供价值导向、度量体系和动力工具.该评价维度包涵资源投入、过程监管、目标实现情况和社会满意度四个方面.文章指出,相关单位以绩效评价推进乡村振兴时应注重顶层设计,强化部门协同,构建评价体系,引入第三方评价主体,凸显农民获得感.     

体育消费的学理脉络、统计内容及其实施策略

采用文献资料法，依次从学理脉络、统计内容及其实施策略展开关于体育消费以及体育消费统计的讨论。认为：从学理上看，体育消费作为一个复杂概念，既牵涉宏观经济社会发展，也与文化意识形态紧密联系；而作为准确把握体育市场、把脉体育发展情况的基础性工作之一，体育消费统计则应该避免将体育消费概念泛化。应以体育政策为导向，面向人民的美好生活需要，对接国民经济统计制度，考虑建构以“体育教育与培训、体育文化与娱乐、体育保健与康复、体育传媒与信息、体育衣着耐用品、其他体育用品与服务、个人间接体育消费”为核心指标的统计框架，并通过长效工作方案的设计使体育消费统计工作制度化，通过统计调查制度的建构使体育消费统计执行有效化，通过统计数据的测算推算使体育消费统计结果精准化。     

面向集成的网络CAPP系统的研究与探索

简述了我国CAPP的发展历程和研究与应用现状 ,提出了CAPP系统应向集成化、网络化方向发展 ,探讨了面向集成的网络化CAPP系统的体系结构、运行机制及其中的一些关键技术     

Variations in Variation and Selection: The Ubiquity of the Variation-and-Selective-Retention Ratchet in Emergent Organizational Complexity, Part II: Quantum Field Theory

If the general arguments concerning theinvolvement of variation and selection inexplanations of ``fit'' are valid, then variationand selection explanations should beappropriate, or at least potentiallyappropriate, outside the paradigm historisticdomains of biology and knowledge. In thisdiscussion, I wish to indicate some potentialroles for variation and selection infoundational physics – specifically inquantum field theory. I will not be attemptingany full coherent ontology for quantum fieldtheory – none currently exists, and none islikely for at least the short term future. Instead, I wish to engage in some partiallyspeculative interpretations of some interestingresults in this area with the aim ofdemonstrating that variation and selectionnotions might play a role even here. Ifvariation and selection can survive in even asinhospitable and non-paradigmatic a terrain asfoundational physics, then it can surviveanywhere.