Linear QSAR Regression Models for the Prediction of Bioconcentration Factors of Chloroanilines in Fish by Density Functional Theory

Density functional theory（DFT）-B3LYP level with the 6-311G＊＊（d,p） basis set was used to calculate a set of molecular quantum chemical descriptors of 12 chloroanilines. Quantitative structure-activity relationship（QSAR） models of the bioconcentration factors（BCF） of the anilines in fish were established using some of the following calculated descriptors： EHOMO, ENHOMO, ELUMO, ENLUMO, ΔE1（= ELUMO- EHOMO）, ΔE2（= ENLUMO- ENHOMO）, dipole moment（μ）, molecular volume（V）, vibrational energy of 0 K（Ev）, thermodynamic energy（E）, heat capacity（Cv）, entropy（Sm） and the charge of benzene ring（Qph）. Using the variable selection and leaps-and-bounds regression, the quantum chemical descriptors derived directly from the molecular structures were employed to develop a linear QSAR model between the bioconcentration factors（BCF） and two descriptors（Sm, ENHOMO） of 12 chloroanilines. Statistically, the most significant one is a two-parameter linear equation with the correlation coefficient（R^2） of 0.981 and cross-validated correlation coefficient（Rcv^2） of 0.967. The established QSAR model has good stability and predictability based on the results from Rcv2 of leave-one-out cross-validation, AIC, FIT and tα/2. The quantum chemical analyses were performed from two aspects of frontier molecular orbital and entropy. The results show that two structural describers are crucial to the bioconcentration activity of chloroanilines.

Period-doubling bifurcation in two-stage power factor correction converters using the method of incremental harmonic balance and Floquet theory

In this paper, period-doubling bifurcation in a two-stage power factor correction converter is analyzed by using the method of incremental harmonic balance （IHB） and Floquet theory. A two-stage power factor correction converter typically employs a cascade configuration of a pre-regulator boost power factor correction converter with average current mode control to achieve a near unity power factor and a tightly regulated post-regulator DC-DC Buck converter with voltage feedback control to regulate the output voltage. Based on the assumption that the tightly regulated postregulator DC-DC Buck converter is represented as a constant power sink and some other assumptions, the simplified model of the two-stage power factor correction converter is derived and its approximate periodic solution is calculated by the method of IHB. And then, the stability of the system is investigated by using Floquet theory and the stable boundaries are presented on the selected parameter spaces. Finally, some experimental results are given to confirm the effectiveness of the theoretical analysis.

New weighting factors assignment of evidence theorybased one vidence distance

Evidence theory has been widely used in the information fusion for its effectiveness of the uncertainty reasoning. However, the classical DS evidence theory involves counter-intuitive behaviors when the high conflict information exists. Based on the analysis of some modified methods, Assigning the weighting factors according to the intrinsic characteristics of the existing evidence sources is proposed, which is determined on the evidence distance theory. From the numerical examples, the proposed method provides a reasonable result with good convergence efficiency. In addition, the new rule retrieves to the Yager's formula when all the evidence sources contradict to each other completely.

Application of the Third Theory of Quantification in Screening Sensitive Geological Factors Influencing Coal and Gas Outburst

The principles of the third theory of quantification were discussed. The concept and calculation method of reaction degree were put forward, which have extended the applying range and scientificalness of the primary reaction. Taking the Zhongmacun mine as an example, the geological factors affecting coal and gas outburst were researched. Eight sensitive factors for the outburst of coal and gas were screened out from 11 geological factors using the method of unit classification and the third theory of quantification. On the basis of this, the Zhongmacun coal mine was classified into several divisions. The practice shows that it is feasible to apply the third theory of quantification to gas geology, which offers a new thought to screen the sensitive geological factors of gas outburst forecast.

Impact of meteorological factors on the incidence of influenza in Beijing: A 35-year retrospective study based on Yunqi theory

Objective:To analyze the impact of meteorological factors on the incidence of influenza based on the Yunqi theory in Beijing area,and to establish an effective forecast modelMethods:Monthly data on the incidence of influenza from 1970 to 2004 and daily data on the meteorological factors (including daily averages of temperature,wind speed,relative humidity,vapor pressure,and daily total precipitation) from 1966 to 2004 were collected and processed under the traditional Chinese medicine (TCM) theory of six qi.A back-propagation artificial neural network was then performed to analyze the data.Results:The highest incidence of influenza occurs in the sixth qi (the period of December and January),which is characterized by dryness and coldness.Altogether six models were successfully established.Climatic data used were of the same year,one year prior,two years prior,and three years prior to the influenza data respectively.The last two models involve climatic data of the previous three years plus the current year and of the past four years plus the current year.Finally,we determined the fifth model has the highest forecast accuracy (49%).Conclusions:Meteorological factors can exert an influence on the incidence of influenza,which corresponds to TCM theory that 'the pestilence occurred three years after the abnormal climatic changes'.This study may generate interest among the public health community and other TCM theories can be applied so that public health measures can be taken to prevent and control influenza,particularly during the winter months.

Hybrid data-driven framework for shale gas production performance analysis via game theory, machine learning, and optimization approaches

A comprehensive and precise analysis of shale gas production performance is crucial for evaluating resource potential,designing a field development plan,and making investment decisions.However,quantitative analysis can be challenging because production performance is dominated by the complex interaction among a series of geological and engineering factors.In fact,each factor can be viewed as a player who makes cooperative contributions to the production payoff within the constraints of physical laws and models.Inspired by the idea,we propose a hybrid data-driven analysis framework in this study,where the contributions of dominant factors are quantitatively evaluated,the productions are precisely forecasted,and the development optimization suggestions are comprehensively generated.More specifically,game theory and machine learning models are coupled to determine the dominating geological and engineering factors.The Shapley value with definite physical meaning is employed to quantitatively measure the effects of individual factors.A multi-model-fused stacked model is trained for production forecast,which provides the basis for derivative-free optimization algorithms to optimize the development plan.The complete workflow is validated with actual production data collected from the Fuling shale gas field,Sichuan Basin,China.The validation results show that the proposed procedure can draw rigorous conclusions with quantified evidence and thereby provide specific and reliable suggestions for development plan optimization.Comparing with traditional and experience-based approaches,the hybrid data-driven procedure is advanced in terms of both efficiency and accuracy.

Analytical Solution for Bending Stress Intensity Factor from Reissner’S Plate Theory

Plate-type structural members are commonly used in engineering applications like aircraft, ships nuclear reactors etc. These structural members often have cracks arising from manufacture or from material defects or stress concentrations. Designing a structure against fracture in service involves consideration of strength of the structure as a function of crack size, dimension and the applied load based on principles of fracture mechanics. In most of the engineering structures the plate thickness is generally small and in these cases though the classical plate theory has provided solutions, the neglect of transverse shear deformation leads to the limitation that only two conditions can be satisfied on any boundary whereas we have three physical boundary conditions on an edge of a plate. In this paper this incompatibility is eliminated by using Reissner plate theory where the transverse shear deformation is included and three physically natural boundary conditions of vanishing bending moment, twisting moment and transverse shear stress are satisfied at a free boundary. The problem of estimating the bending stress distribution in the neighbourhood of a crack located on a single line in an elastic plate of varying thickness subjected to out-of-plane moment applied along the edges of the plate is examined. Using Reissner’s plate theory and integral transform technique, the general formulae for the bending moment and twisting moment in an elastic plate containing cracks located on a single line are derived. The thickness depended solution is obtained in a closed form for the case in which there is a single crack in an infinite plate and the results are compared with those obtained from the literature.

The core ideology of Ecological Marxism:Marx is the pioneer of internal factors theory of ecological environment

This paper from the unified visual angle of philosophy and economics has observed Marx's theory of ecological economics, clarified the misunderstanding on Marx's theory of nature and ecological environmental thought at home and abroad for a long time, studied systematically and deeply the Marx's thought that natural and ecological environment is external condition and internal elements of human social economic growth, confirmed firstly Marx is the forerunner who established the theory of internal cause of natural ecological environment. It is of far-reaching academic and practical significance.

An Extended Fuzzy-DEMATEL System for Factor Analyses on Social Capital Selection in the Renovation of Old Residential Communities

China has been promoting the renovation of old residential communities vigorously.Due to the financial pressure of the government and the sustainability of the renovation of old residential communities,public-private partnerships(PPP)have already gained attention.The selection of social capital is key to improving the efficiency of the PPP model in renovating old residential communities.In order to determine the influencing factors of social capital selection in the renovation of old residential communities,this paper aims to find an effective approach and analyze these factors.In this paper,a fuzzy decision-making and trial evaluation laboratory(fuzzy-DEMATEL)technique is extended and amore suitable systemis developed for the selection of social capital using the existing group decisionmaking theory.In the first stage,grounded theory is used to extract the unabridged key influencing factors for social capital selection in the renovation of old residential communities.Secondly,by considering the impact of expert weights,the key influencing factors are identified.The interactions within these influencing factors are discussed and the credibility of the results is verified by sensitivity analysis.Finally,these key influencing factors are sorted by importance.Based on the results,the government should focus on a technical level,organizationalmanagement abilities,corporate reputation,credit status,etc.This study provides the government with a theoretical basis and a methodology for evaluating social capital selection.

Role of vascular endothelial growth factor B in nonalcoholic fatty liver disease and its potential value

Nonalcoholic fatty liver disease(NAFLD)refers to fatty liver disease caused by liver injury factors other than alcohol.The disease is characterized by diffuse fat infiltration,including simple steatosis(no inflammatory fat deposition),nonalcoholic fatty hepatitis,liver fibrosis,and so on,which may cause liver cirrhosis,liver failure,and even liver cancer in the later stage of disease progression.At present,the pathogenesis of NAFLD is still being studied.The"two-hit"theory,represented by lipid metabolism disorder and inflammatory reactions,is gradually enriched by the"multiple-hit"theory,which includes multiple factors,such as insulin resistance and adipocyte dysfunction.In recent years,vascular endothelial growth factor B(VEGFB)has been reported to have the potential to regulate lipid metabolism and is expected to become a novel target for ameliorating metabolic diseases,such as obesity and type 2 diabetes.This review summarizes the regulatory role of VEGFB in the onset and development of NAFLD and illustrates its underlying molecular mechanism.In conclusion,the signaling pathway mediated by VEGFB in the liver may provide an innovative approach to the diagnosis and treatment of NAFLD.

On Dynamic Social Factors for Development of China’s Human Rights Theory

China＇s mainstream human rights theory has undergone tremendous changes since the reform-and-opening scheme was kicked off in the early 1980s. ＂Human rights,＂ which used to be seen as a concept of capitalist ideology, is now an important part of the Chinese system of socialist values.

基于扎根理论的政府开放数据价值影响因素研究

[目的/意义]政府开放数据价值是数字经济情境下个体数据行为嬗变的反馈性标志。从政府开放数据使用者视角识别其价值要素,对于促进政府数据管理水平,提升数据交易常态化具有理论和实践意义。[方法/过程]利用会议、访谈与网络数据获取原始资料,结合扎根理论,构建“三维—多层”的数据价值影响因素模型,涵盖121个初始概念、30项范畴和9项主范畴,各领域受访者共33位。[结果/结论]个体感知数据价值影响因素主要涉及需求、进路、市场化三个维度,综合考察各项主范畴,针对数据价值的内在关联以及外部机制,可以提炼出直接、间接、跨层、双元4种关系结构。这个过程在理论上弥补了传统政务体系下政府开放数据与个体需求二元割裂之不足,延展了政府开放数据的价值使用行为与价值释放路径。

基于扎根理论的景区红色文化传播影响因素探析

景区红色文化传播对提升游客红色文化认知、增强红色旅游教育功能具有重要的推动作用,加强红色文化旅游传播的理论研究是一个需要解决的现实问题。为厘清景区内影响游客对红色文化认知的因素及这些因素的作用机理,通过深度访谈获取一手资料,以扎根理论方法提炼出景区红色文化传播的影响因素并构建理论模型。研究发现,影响景区红色文化传播因素为受众态度、受众知觉、社会因素、解说形式、信息流、体验情境因素。其作用机制为:受众态度、知觉通过红色旅游意向与行为影响景区红色文化传播;社会因素调节红色旅游意向;解说形式和体验情境作为直接因素影响景区红色文化传播;信息流作为调节变量影响景区文化传播的方向与被识别度。其中,游客对红色历史图片、文字和人员解说的态度与要求具有不同的期望和评判,体现了游客对红色景区解说形式的要求。

基于SEM-ANN的数字人民币使用意愿影响因素研究

数字人民币是重塑我国支付新格局、加速数字经济进程的重要载体,但在用户推广方面仍存在诸多阻力,从用户的视角探究数字人民币使用意愿的影响因素具有重要的意义。本文以数字人民币为研究对象,在UTAUT2模型的基础上结合数字人民币的特点,构建数字人民币使用意愿理论模型;进而,以数字人民币首批试点城市的用户数据为样本,综合运用PLS-SEM和SEM-ANN方法实证分析数字人民币使用意愿的影响因素。结果表明,基于SEM的数字人民币使用意愿模型具有较好的解释和预测能力;信任、习惯、价格价值和社会影响对数字人民币使用意愿具有显著正向影响,而绩效期望、努力期望和创新意识对数字人民币使用意愿的影响不显著;此外,在作为调节变量的个人特征方面,价格价值与数字人民币使用意愿的关系受性别因素的调节;经验对价格价值、习惯、社会影响、信任与用户使用意愿的关系均具有调节作用;将结构方程模型与人工神经网络相结合能够提升模型的预测精度,并且影响因素的重要性有所改变,习惯最为重要、信任次之,其次为社会影响和价格价值。

基于扎根理论的中国数据新闻受众接受行为研究

数据新闻是随着媒介技术的发展而出现的一种新型报道形态,自2011年以来各大媒体争相使用数据新闻报道新闻。然而,由于受众对数据新闻的类型特征、创新意义和新闻价值认知不足,导致数据新闻的社会接受度不高,严重影响了数据新闻的舆论影响力和社会效益。研究以扎根理论为基础,通过深度访谈收集数据新闻作品温度、媒体资质和网络环境等因素对受众接受行为的影响,继而对访谈资料进行开放式编码、主轴式编码和选择性编码,构建出影响数据新闻传播的理论模型。研究发现:环境因素、渠道因素、内容因素、有媒体因素和受众因素影响数据新闻的发展和传播。基于相关实证研究和理论探索,本文针对性提出打造智慧新闻平台、技术赋能新闻生产、构建信度指标体系、稳步推进信息定制等创新策略和建议,为数据新闻的持续健康发展提供有益借鉴。

基于数量化理论Ⅰ的女西服款式感性评价

为了设计出符合消费者感性需求的服装产品,以女西服为研究对象,提出感性工学与数量化理论Ⅰ相结合的款式设计研究方案。首先通过语意差异法获取消费者对女西服样本的感性评价,利用SPSS软件对感性评分进行分析,提取感性因子,创建女西服二维感性分布空间。同时分析款式特征,归纳出女西服主要设计要素,在此基础上应用数量化理论Ⅰ,通过线性回归分析得出感性因子与设计要素之间的关联预测,并构建数学模型。经验证,该模型实测值与预测值之间拟合度较高,符合正态分布要求,模型有效可行。最后通过案例设计与验证,进一步证明该模型能够实现人的感性需求与女西服设计要素之间的有效转换,对女西服款式设计与感性评价提供一定借鉴作用。

数字化转型能提升农业企业全要素生产率吗?

基于2007—2020年我国A股上市农业企业的微观数据,实证分析数字化转型对农业企业全要素生产率的影响及其机制。研究表明,数字化转型有利于提升农业企业的全要素生产率。机制检验表明,数字化转型通过提高资金利用率、降低超额雇员率、增大研发投入来提高农业企业全要素生产率。调节效应检验表明,营商环境不确定性、行业竞争强度加剧将削减数字化转型对农业企业全要素生产率的提升效果。异质性检验表明,数字化转型对小规模农业企业、处于成长期和成熟期的农业企业、国有农业企业、两职分离的农业企业全要素生产率的提升作用更为显著。为此,政府等治理主体应完善数字基础设施,营造良好营商环境和市场竞争秩序,优化农业企业数字化转型的外部环境;同时农业企业也要根据自身发展实际,科学配置资金、技术、劳动力等资源,选择适宜的数字化转型路径。

川藏南线自驾游客情感体验的特征与影响机制

以流动性体验为核心的旅游形式在全球化背景下日益流行。作为大尺度流动型旅游形式典型代表的长途自驾游,因冒险、追逐自由、私密、个性化、高不确定性等特征,赋予了游客独特且复杂的情感体验。目前,学界尚缺乏从更为系统的视角关注大尺度流动情境下游客情感体验的特征、前因与影响机制的实证研究。文章基于景观感知理论,采用定量研究与定性研究相结合的方法,以川藏南线(318国道成都至拉萨段)的自驾游客为研究对象,分析游客在大尺度流动情境下的情感体验特征与影响机制。文章发现:1)自驾游客的积极情感体验未达强烈水平,情感体验(尤其是积极情感体验)伴随着自驾这一流动性实践呈现出动态变化的波动特征,且涉及多个维度;2)基于自我需要满足与否、满足程度如何这一标准,自驾游客与环境的互动(包含两组类型、6类特征)促进了他们上述情感体验的产生,并通过动态反馈机制持续影响了情感体验。上述研究发现不仅完善了有关游客情感体验前因和影响机制以及自驾入藏旅游体验的实证研究体系,还为目的地的管理与营销提供了思路。

社区营造中的城市居民:为何参与及何以可为?——以沈阳市X区“车棚革命”为例

实现人自由而全面的发展是中国式现代化的最终目标。社区营造“造人”的核心追求与之不谋而合,尤其关注最为核心、最具规模的社区居民。以对社区居民的深度访谈字表为研究对象,运用扎根理论方法探究城市居民参与社区营造的影响因素,并构建城市居民参与社区营造行为选择模型。研究发现,态度、主观规范、党委领导、政府负责、社区动员、社区社会资本以及自我效能感七大因素构成城市居民参与社区营造的影响因素,作为实现因素的自我效能感在倾向因素、环境因素、组织因素和参与行为之间起中介作用,态度和主观规范相互影响。主体信念是行为选择的根本性指引,城市社区居民参与社区营造理应回归培植个体公共性、建构共同体意识的逻辑之中。未来应该从个体塑造和组织促成两个维度发力,以需求撬动居民态度和自我效能感,以互动培育社区社会资本,发挥党委、政府、社区自治组织等主体的协同作用,构建人人有责、人人尽责、人人享有的社会治理共同体。

重大突发公共卫生事件中老年用户信息公开满意度影响因素模型构建——以成都市为例

[目的/意义]作为数字时代的信息弱势群体,重大突发公共卫生事件中老年用户的信息公开满意度将是影响各级政府风险与应急管理效果的重要因素。[方法/过程]文章选取成都市老年群体为具体研究对象,运用访谈和扎根理论方法,分析获取重大突发公共卫生事件中老年用户信息公开满意度的关键影响因素并构建影响因素框架模型。[结果/结论]以信任程度、主观能力、需求期望和社会支持等为自变量,以感知易获取性、感知质量和感知价值为中间变量模型,揭示了重大突发公共卫生事件老年用户信息公开满意度影响因素的多元性与作用关系的复杂性,体现了老年用户作为信息弱势群体在重大突发公共卫生事件公开信息获取与利用中的信息心理与行为特质。