Computational Experiments for Complex Social Systems:Experiment Design and Generative Explanation

Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a novel approach for the design,analysis,management,control,and integration of CPSS,which can realize the causal analysis of complex systems by means of“algorithmization”of“counterfactuals”.However,because CPSS involve human and social factors(e.g.,autonomy,initiative,and sociality),it is difficult for traditional design of experiment(DOE)methods to achieve the generative explanation of system emergence.To address this challenge,this paper proposes an integrated approach to the design of computational experiments,incorporating three key modules:1)Descriptive module:Determining the influencing factors and response variables of the system by means of the modeling of an artificial society;2)Interpretative module:Selecting factorial experimental design solution to identify the relationship between influencing factors and macro phenomena;3)Predictive module:Building a meta-model that is equivalent to artificial society to explore its operating laws.Finally,a case study of crowd-sourcing platforms is presented to illustrate the application process and effectiveness of the proposed approach,which can reveal the social impact of algorithmic behavior on“rider race”.

Design and analysis of an advanced thermal management system for the solar close observations and proximity experiments spacecraft

In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relationship and functions of the integrated database,the intelligent thermal control system and the efficient liquid cooling system in the ATMS are elaborated upon.For the complex thermal field regulation system and extreme space thermal environment,a modular simulation and thermal field planning method are proposed,and the feasibility of the planning algorithm is verified by numerical simulation.A solar array liquid cooling system is developed,and the system simulation results indicate that the temperatures of the solar arrays meet the requirements as the spacecraft flies by perihelion and aphelion.The advanced thermal management study supports the development of the SCOPE program and provides a reference for the thermal management in other deep-space exploration programs.

Flume experiments to study fine-grain migration and its impact on slope stability

Fine grains migration is a primary cause of landslides and debris flows.This study investigates the effect of fine-grain migration on slope failure through flume experiments,focusing on the spatiotemporal characteristics and mechanisms of slope stability.A series of artificial rainfall flume experiments with varying rainfall intensities and slopes were conducted using soil samples collected from Wei Jia Gully.The experiments monitored pore-water pressure,grain migration,and failure sequences.Grain-size distribution parameters(μand Dc)were analyzed to understand the migration path and accumulation of fine grains.The experiments reveal that fine-grain migration significantly alters soil structure,leading to random blockage and interconnection of internal pore channels.These changes result in fluctuating pore-water pressure distributions and uneven fine-grain accumulation,critical factors in slope stability.Slope failures occur randomly and intermittently,influenced by fine-grain content in runoff and resulting pore-water pressure variations.This study highlights that fine-grain migration plays a vital role in slope stability,with significant implications for predicting and mitigating slope failures.The stochastic nature of fine-grain migration and its impact on soil properties should be incorporated into predictive models to enhance their accuracy and reliability.

Mechanical heterogeneity characterization of coal materials based on nano-indentation experiments

To investigate the complex macro-mechanical properties of coal from a micro-mechanical perspective,we have conducted a series of micro-mechanical experiments on coal using a nano-indentation instrument.These experiments were conducted under both dynamic and static loading conditions,allowing us to gather the micro-mechanical parameters of coal for further analysis of its micro-mechanical heterogeneity using the box counting statistical method and the Weibull model.The research findings indicate that the load–displacement curves of the coal mass under the two different loading modes exhibit noticeable discreteness.This can be attributed to the stress concentration phenomenon caused by variations in the mechanical properties of the micro-units during the loading process of the coal mass.Consequently,there are significant fluctuations in the micro-mechanical parameters of the coal mass.Moreover,the mechanical heterogeneity of the coal at the nanoscale was confirmed based on the calculation results of the standard deviation coefficient and Weibull modulus of the coal body’s micromechanical parameters.These results reveal the influence of microstructural defects and minerals on the uniformity of the stress field distribution within the loaded coal body,as well as on the ductility characteristics of the micro-defect structure.Furthermore,there is a pronounced heterogeneity in the micromechanical parameters.Furthermore,we have established a relationship between the macro and micro elastic modulus of coal by applying the Mori-Tanaka homogenization method.This relationship holds great significance for revealing the micro-mechanical failure mechanism of coal.

Predicting the probability distribution of Martian rocks mechanical property based on microscale rock mechanical experiments and accurate grain-based modeling

The exploration of Mars would heavily rely on Martian rocks mechanics and engineering technology.As the mechanical property of Martian rocks is uncertain,it is of utmost importance to predict the probability distribution of Martian rocks mechanical property for the success of Mars exploration.In this paper,a fast and accurate probability distribution method for predicting the macroscale elastic modulus of Martian rocks was proposed by integrating the microscale rock mechanical experiments(micro-RME),accurate grain-based modeling(AGBM)and upscaling methods based on reliability principles.Firstly,the microstructure of NWA12564 Martian sample and elastic modulus of each mineral were obtained by micro-RME with TESCAN integrated mineral analyzer(TIMA)and nanoindentation.The best probability distribution function of the minerals was determined by Kolmogorov-Smirnov(K-S)test.Secondly,based on best distribution function of each mineral,the Monte Carlo simulations(MCS)and upscaling methods were implemented to obtain the probability distribution of upscaled elastic modulus.Thirdly,the correlation between the upscaled elastic modulus and macroscale elastic modulus obtained by AGBM was established.The accurate probability distribution of the macroscale elastic modulus was obtained by this correlation relationship.The proposed method can predict the probability distribution of Martian rocks mechanical property with any size and shape samples.

Ballistic limit velocity of small caliber projectiles against SS400 steel plates:Live fire experiments and empirical models

This study presents the ballistic limit velocity of small caliber projectiles against SS400 steel plate derived from live-fire ballistic experiments. Four different small caliber projectiles were tested against SS400 steel plates of 9 mm, 10 mm, and 12 mm thicknesses. The ballistic limit velocity was calculated using two standard methods, MIL-STD-662F and NIJ-STD-0101.06, and additionally using a support vector machine algorithm. The results show a linear relationship between the plate thickness and ballistic limit velocity. Further, the relative penetration performance among five different small caliber projectiles was analyzed using the Penetration Performance Ratio(PPR) introduced in this study, which suggests the potential of PPR to predict the ballistic limit velocity of other untested materials and/or different projectiles.

Rotating tank experiments for the study of geophysical fluid dynamics

Geophysical fluid dynamics(GFD)is an interdisciplinary field that studies the large-scale motion of fluids in the natural world.With a wide range of applications such as weather forecasts and climate prediction,GFD employs various research approaches including in-situ observations,satellite measurements,numerical simulations,theoretical analysis,artificial intelligence,and physical model experiments in laboratory.Among these approaches,rotating tank experiments provide a valuable tool for simulating naturally-occurring fluid motions in laboratories.With proportional scaling and proper techniques,scientists can reproduce multi-scale physical processes of stratified fluids in the rotation system,which allows for the simulation of essential characteristics of fluid motions in the atmosphere and oceans.In this review,rotating tanks of various scales in the world are introduced,as these tanks have been actively used to explore fundamental scientific questions in ocean and atmosphere dynamics.To illustrate the GFD experiments,three representative cases are presented to demonstrate the frontier achievements in the the GFD study by using rotating tank experiments:mesoscale eddies in the ocean,convection processes,and plume dynamics.Detailed references for the experimental procedures are provided.Future studies are encouraged to further explore the utilization of rotating tanks with improvements in experimental design and integration of other research methods.This is a promising direction of GFD to help enhance our understanding of the complex nature of fluid motions in the natural world and to address the challenges posed by global environmental changes.

Study on the effect and mechanism of Swertia mussotii Franch. in the treatment of primary biliary cholangitis based on bioinformatics and in vitro experiments

Background:Primary biliary cholangitis(PBC)is a chronic biliary autoimmune liver disease characterized by intrahepatic cholestasis.Swertia mussotii Franch.(SMF)is a Tibetan medicine with hepatoprotective and anti-inflammatory activities.In this study,the therapeutic effect and potential mechanisms of SMF on PBC were investigated by bioinformatics analysis and in vitro experimental validation,with the aim of promoting the progress of SMF and PBC research.Methods:We first explored the therapeutic effects and key targets of SMF on PBC using a network pharmacology approach,further screened the core targets using the GSE79850 dataset,and finally validated the results using molecular docking techniques and in vitro experiments.Results:By bioinformatics analysis,we identified core targets of SMF for PBC treatment(STAT3,JAK2,TNF-α,and IL-1β)and important signaling pathways:JAK-STAT,TNF,and PI3K-AKT.The molecular docking results showed that the significant components of SMF had good binding properties to the core targets.In vitro experiments showed that SMF extracts improved the extent of epithelial-mesenchymal transition in human intrahepatic biliary epithelial cells and had a significant reversal effect on epithelial-mesenchymal transition process markers and potential targets in PBC.Conclusion:SMF may exert its therapeutic effects on PBC by acting on important targets such as STAT3,JAK2,TNF-α,IL-1β,Vimentin,and E-cadherin and the pathways in which they are involved.

Teaching Status and Teaching Reform Ideas of Physical Chemistry Experiments for Food Quality and Safety Major

Physical chemistry experiments are an important branch of chemical experiments.In view of problems and shortcomings in physical chemistry experiment teaching of food quality and safety major in Chengdu University,the teaching methods of physical chemistry experiment course of food quality and safety major were explored and practiced,aiming to arouse students enthusiasm for experiments and cultivate their ability of independent learning,comprehensive thinking and independent problem solving.

Laboratory Experiments Do Not Support the Greenhouse Effect as Applicable to CO2

The analysis of Greenhouse Effect experiments in the public domain indicated that the lab tests were primarily centered around illustrating the mechanics of conventional greenhouses. They used high-energy visible light (such as sunlight), rather than addressing the Greenhouse Effect, which involves low-energy infrared radiation emitted by the Earth’s surface. Studies with argon, a non-greenhouse gas with similar density to CO2, showed thermal heat transfer as the dominant factor in the temperature profiles, with radiation absorption being undetected. The same conclusion was drawn by another study, which measured infrared back radiation. Experiments using exaggerated CO2 concentrations inadvertently illustrated the principle of the Popper Falsification Test by disproving the Greenhouse Effect applicable to CO2 within the troposphere. A straightforward kitchen test showed that a microwave oven cannot be used as a model for the Greenhouse Effect.

Exploration of playa surface crusts in Qehan Lake, China through field investigation and wind tunnel experiments

Globally,many lakes are drying up,leaving exposed lakebeds where wind erosion releases dust and sand rich in salt and harmful heavy metals into the atmosphere.Therefore,understanding the characteristics and spatial distribution of playa surface crusts is important to recognize the manifestation of salt dust storms.The objective of this study was to explore the playa surface crust types as well as their spatial distribution and evolution of Qehan Lake in Inner Mongolia Autonomous Region,China to understand the salt dust release potential of different types of playa surface crusts.Various crust characteristics were investigated by field sampling in Qehan Lake,and playa surface crusts were further divided into five types:vegetated areas,salt crusts,clay flats,curly crusts,and margins.It should be noted that curly crusts were distributed in clay flats and covered only a small area in Qehan Lake.The spatial distribution characteristics of playa surface crust types were obtained by supervised classification of remote sensing images,and the salt dust release potential of crusts was explored by the wind tunnel experiments.The field investigation of Qehan Lake revealed that playa surface crust types had a circum-lake band distribution from the inside to the outside of this lake,which were successively vegetated areas,clay flats,salt crusts,and margins.The spatial distribution patterns of playa surface crust types were mainly controlled by the hydrodynamics of the playa,soil texture,and groundwater.There was a significant negative correlation between crust thickness and electrical conductivity.The results of the wind tunnel experiments showed that the initial threshold of friction wind velocity for the salt dust release was higher in clay flats(0.7–0.8 m/s)than in salt crusts(0.5–0.6 m/s).Moreover,the particle leap impact processes occurring under natural conditions may reduce this threshold value.Salinity was the main factor controlling the difference in the initial threshold of friction wind velocity for the salt dust release of clay flats and salt crusts.This study provides a scientific reference for understanding how salt dust is released from a lakebed,which may be used for ecological restoration of dry salt lakes.

Process Characterization of the Transesterification of Rapeseed Oil to Biodiesel Using Design of Experiments and Infrared Spectroscopy

For optimization of production processes and product quality,often knowledge of the factors influencing the process outcome is compulsory.Thus,process analytical technology(PAT)that allows deeper insight into the process and results in a mathematical description of the process behavior as a simple function based on the most important process factors can help to achieve higher production efficiency and quality.The present study aims at characterizing a well-known industrial process,the transesterification reaction of rapeseed oil with methanol to produce fatty acid methyl esters(FAME)for usage as biodiesel in a continuous micro reactor set-up.To this end,a design of experiment approach is applied,where the effects of two process factors,the molar ratio and the total flow rate of the reactants,are investigated.The optimized process target response is the FAME mass fraction in the purified nonpolar phase of the product as a measure of reaction yield.The quantification is performed using attenuated total reflection infrared spectroscopy in combination with partial least squares regression.The data retrieved during the conduction of the DoE experimental plan were used for statistical analysis.A non-linear model indicating a synergistic interaction between the studied factors describes the reactor behavior with a high coefficient of determination(R^(2))of 0.9608.Thus,we applied a PAT approach to generate further insight into this established industrial process.

授人以鱼和渔:仪器分析实验自主设计实验及思政元素融入

为适应现代教育理念及国家对创新型人才的需求,改革传统实验教学模式并激发学生的自主创新意识,在传统仪器分析实验教学基础上探索和构建以学生为主体、以创新能力培养为中心的自主设计实验教学模式。课程在夯实基础和拔高创新方面取得了平衡,同时拓展了课程思政的范畴,如以学生为中心的自主设计实验模式提升了学生学习主动性,课程高阶性、创新性显著提高,授课教师在更多方面以身作则,示范了严谨的科学态度,并倡导了积极的科学探索态度。通过自主设计实验的开展,学生的基础知识、学习兴趣、实验技能、创新能力等都得到了显著提升,建立了有效的仪器分析学习模式。

图书馆沉浸式阅读推广模式构建及优化策略——以长沙市图书馆为例

文章结合长沙市图书馆沉浸式阅读推广实践,基于沉浸式体验的9个要素及图书馆阅读推广的设计、实施、反馈3个阶段,构建图书馆沉浸式阅读推广模式,并提出图书馆沉浸式阅读推广优化策略,即分层分级明确目标,激发读者的思维沉浸;创新阅读推广场景,强化读者主动参与意识;增强读者心流体验,持续提高活动的吸引力。

完整经验的基本涵义、生成机制及其教育意蕴

完整经验具有与经验同一的动态性、生成性等本质特征,蕴含着过程取向的完整观。完整经验的生成应以生活经验与课程经验的交互为基础,以认知经验与社会经验的融合为条件,以反省经验到审美经验的升华为关键。基于完整经验的幼儿园教育变革,在课程设置方面,要体现经验的多样性、连续性、过程性和整合性,注重经验向反省经验、审美经验的进阶与升华,应整体考虑生活经验、社会经验和审美经验之于幼儿学习与发展的价值。在教学过程中,应提供适宜的支架,珍视幼儿生活经验的独特价值,创设真实的问题解决情境。

面向林学专业群的有机化学实验教学内容改革实践与探索

作为高等学校公共基础课,有机化学实验因教学资源不足,普遍存在教学内容千篇一律、与专业特色契合度低等问题,导致学生学习动力不足。本文结合西南林业大学实际,尝试将具有植物资源培养、开发、利用的相关专业组成林学专业群,并针对该专业群,构建了以天然产物提取、分离、纯化、鉴定为主线的有机化学实验教学体系。学生期末考试表现及问卷调查结果表明,新教学体系对提升学生学习兴趣、改善学生培养质量具有显著的推进作用,同时也为在教学体系中融入农林特质提供了思路。

王静波临床经验总结

王静波教授从事中医眼科工作40余年,积累了丰富的临床经验。特别是在中晚期青光眼的治疗方面,王静波教授研习古籍,结合自己的临床经验,认为中晚期青光眼及术后视神经萎缩、小视野者,主要是因为阴不涵阳,肝阳失于制约,肝阳上亢,阳热耗气伤阴,终至气阴两亏;气阴亏损目之窍道无力以通,无物以养而视物不清。制定了益气养阴开窍为治则治疗中晚期青光眼,并创制了益气养阴、开窍明目的益阴明目合剂。为中晚期青光眼的治疗提供了新的思路。同时在春季卡他性结膜炎、麦粒肿等疾病方面也有独特的治疗方法。治疗春季卡他性结膜炎时,王静波老师治疗本病从整体出发,通过辨证论治调理体质,联合中药外熏洗及内服、药渣外敷等多种中医疗法,既能固其本,又能治其标,内外结合、标本兼治,缩短病程,减少复发。王静波教授还根据多年临床经验,总结出经验方内服结合药渣外敷并配合耳尖放血治疗麦粒肿,内外治结合收到显著疗效。该文对以上进行总结,旨在继承名老中医经验,促进中医眼科的学术发展。

激光诱导击穿光谱(LIBS)分析虚拟仿真实验

虚拟仿真实验作为大型仪器分析实验教学模式的新兴趋势,有效地将虚拟仿真技术与实物仪器教学相结合,最大限度地提升了学生对于大型仪器分析的综合应用能力。本文以激光诱导击穿光谱(LIBS)虚拟仿真实验系统为例,完整地模拟了LIBS系统的样品处理、光谱采集、定性分析和定量分析等实际实验场景,通过虚实结合实验教学模式对实验过程进行实时跟踪与综合考评。该实验有助于提高学生自主探究能力和创新意识,培养具有独立思考与实践能力的拔尖人才。

工程教育视角下化工原理实验课程建设的思考

根据化工原理实验课程综合性、设计性和实践性强的特点,提出层次化实验教学方式,不断培养学生学习兴趣,提高创新思维和能力水平。同时,结合教学经验,在课程预习及实验操作等方面对实验课程的教学过程和考核方式进行改进,充分调动了学生实验学习的积极性,使学生掌握实验技能,有助于培养学生的工程意识、实践能力,不断提升教学效果,全面提高化工原理实验课程教学质量。

新农科背景下分子生物学实验教学改革探索

以分子生物学为主要内容的现代生物技术已被纳入到新农科的知识范畴。简单借鉴综合性大学的分子生物学实验课教学方案,已不能完全符合新农科建设的需求。该文详细分析影响涉农专业分子生物学实验课程教学效果的主要问题,并提出切合新农科建设思路,融合翻转课堂、PBL(Problem-based Learning)、OBE(Outcomes-based Education)等教学模式的多元教学解决方案。针对传统农科人才培养中重视实际操作,但总结和表述能力培养相对不足的实际,设立以“做得好、写得好、讲得好”为评价教学效果的新标准。初步实践表明,该方案的实施能提高学生参与实验课程的主动性,在教授学生实验操作技能的同时,培养学生的创新精神和团结协作精神。在全面培养新农科学生综合实验能力和科学素质方向上,做出有益的探索。