基于新冠病毒特征及防控措施的传播动力学模型

本文针对现有传染病传播动力学模型的不足,结合新冠病毒(2019-nCoV)特征及防控措施,建立一种新的包含"易感、未隔离潜伏期、已隔离潜伏期、确诊感染、无症状感染、确诊后治愈、无症状感染后治愈、因病死亡"等8个仓室的传染病模型.在模型中考虑状态转移参数的饱和特性,以模拟大量隔离患者对隔离点运行造成的压力、大量确诊患者给医院运行带来的压力.在参数配置方面,考虑状态转移参数在疫情不同发展阶段的时变特性,建立参数辨识模型并利用马尔可夫链蒙特卡罗算法进行求解.此外,从传播规模、传播峰值和传播峰值时间三个维度建立疫情传播风险指标,全面评估疫情传播风险.武汉和国外(美国、西班牙)疫情的案例分析表明,本模型相较于其他经典模型,能够准确拟合新冠肺炎(COVID-19)的传播趋势,揭示疫情传播机理.     

追溯新型冠状病毒肺炎的动力学变化过程

2019新型冠状病毒肺炎（COVID-19）是一种全球性流行性疾病.利用贝叶斯系统发育的方法，根据病毒的基因序列来推断有效再生数R_e随着时间推移所产生的变化，并用它来表现该病毒流行的动态.研究结果显示：R_e随时间变化并不太大，R_e最高点的中值为2.88（95% HPD：2.3~3.46），最低点在2020年1月29日左右，其中值为2.74（95% HPD：2.27~3.26）.该研究提供了COVID-19流行病学的一些关键参数值，希望这些结论能够帮助同行用数学建模的方法来更好地估计疾病早期的未知参数.     

基于BERT-LDA模型的新冠肺炎疫情网络舆情演化仿真

构建大规模网络舆情演化仿真模型,对新冠疫情武汉重灾区与全国其他地区采取差异化的应急管理和舆情疏导具有指导价值.为实现主题细粒度的舆情情感演化仿真,将LDA(LatentDirichlet Allocation)主题模型与BERT(Bidirectional Encoder Representations from Tr...     

The Newtonian Myth

I examine Popper’s claims about Newton’s use of induction in Principia with the actual contents of Principia and draw two conclusions. Firstly, in common with most other philosophers of his generation, it appears that Popper had very little acquaintance with the contents and methodological complexities of Principia beyond what was in the famous General Scholium. Secondly Popper’s ideas about induction were less sophisticated than those of Newton, who recognised that it did not provide logical proofs of the results obtained using it, because of the possibilities of later, contrary evidence. I also trace the historical background to commonplace misconceptions about Newton’s method.     

Actants and enframing: Heidegger and Latour on technology

A central issue in the philosophy of technology concerns the relationship between technology and the conditions under which technology develops. Traditionally, two main accounts are given of this relationship. The social constructivist approach considers technology to be largely determined by “social” factors (e.g. military interests, economic policy). By contrast, technological determinism describes technology as self-determinative, and as following its own independent aim of greater efficiency. This paper discusses two alternatives to these conceptions of technology, namely, the accounts offered by Bruno Latour and Martin Heidegger. It examines their common theses that our present misunderstanding of technology is due to a continued commitment to the subject–object distinction. The paper further compares their accounts, which attempt to overcome this distinction, and argues that ultimately both authors fail to find a role for human beings that is consistent with their contention that we need to develop a less anthropocentric understanding of the world.     

On the necessary truth of the laws of classical mechanics

The idealization of primitive mechanical experience is shown to lead to four mutually related formulations of classical mechanics based on connections, action at a distance, stresses, and collisions. For a given structure of spacetime and a given characterization of mechanical systems, fundamental laws (including Newton's law of acceleration and d’Alembert's principle) are derived from a few general principles regarding the comprehensibility of motion. Special emphasis is placed on the “secular principle,” according to which the evolution of a system at the relevant time scale should not depend on finer details of the applied forces.     

858例奥密克戎变异株新型冠状病毒感染住院患者死亡转归影响因素分析

本文主要通过回顾性研究新型冠状病毒感染(奥密克戎流行毒株)患者临床资料,探讨患者死亡的影响因素。以2022年12月至2023年1月在广西医科大学第二附属医院收治的经基因测序诊断为奥密克戎变异株新型冠状病毒感染患者906例为研究对象,根据纳入标准和排除标准,最终纳入患者858例,其中809例患者好转并出院,49例患者死亡。回顾性分析比较出院患者和死亡患者临床资料,并进行多因素逻辑回归分析患者死亡的影响因素。结果显示,两组患者在年龄(t=-0.640)、接种新冠疫苗(χ²=7.673)、高血压(χ²=9.557)、糖尿病(χ²=11.092)、脑梗(χ²=5.810)、发热(χ²=14.418)、呼吸困难(χ²=56.878)、味觉异常/丧失(χ²=5.876)、肺部啰音(χ²=27.655)及意识障碍(χ²=48.084)上存在显著差异(P<0.05)。多因素逻辑回归分析显示,年龄(OR...     

疫情下考虑疲劳度的可变服务率排队模型

在新型冠状病毒疫情爆发期间，针对医院因医疗资源调度不合理导致的医生超疲劳状态工作、救治率下降等问题， 量化研究急诊医生疲劳度影响因子，应用熵权–模糊层次分析法计算各因子的影响权重，通过合理配置、政策缓压、科学轮休的方法，最大限度降低医生在应急诊疗中的疲劳度值。同时，根据医生的工作时间长度设置可变的服务速率，运用生灭过程模型分析患者的排队序列。最后使用ProModel仿真软件将模型进行可视化分析，设置实验组与对照组进行对比研究。仿真结果显示，考虑疲劳度排队模型的患者输出率、医生座席利用率等服务指标均优于传统模型，同时也使医生疲劳度和患者满意度达到一个动态平衡状态。