Research on the Relationship Between Environmental and Economic Coupling Systems in Bohai Bay Area Based on a Vector Autoregression(VAR)Model

This study analyzed the impact of land-based contaminants and tertiary industrial structure on economic development in the selected Bohai Bay area,China.Based on panel data spanning 2011-2020,a vector autoregressive(VAR)model is used to analyze and forecast the short-run and long-run relationships between three industrial structures,pollutant discharge,and economic development.The results showed that the environmental index had a long-term cointegration relationship with the industrial structure economic index.Per capital chemical oxygen demand(PCOD)and per capita ammonia nitrogen(PNH_(3)N)had a positive impact on delta per capita GDP(dPGDP),while per capita solid waste(PSW),the secondary industry rate(SIR)and delta tertiary industry(dTIR)had a negative impact on dPGDP.The VAR model under this coupling system had stability and credibility.The impulse response results showed that the short-term effect of the coupling system on dPGDP was basically consistent with the Granger causality test results.In addition,variance decomposition was used in this study to predict the long-term impact of the coupling system in the next ten periods(i.e.,ten years).It was found that dTIR had a great impact on dPGDP,with a contribution rate as high as 74.35%in the tenth period,followed by the contribution rate of PCOD up to 3.94%,while the long-term contribution rates of PSW,SIR and PNH3N were all less than 1%.The results show that the government should support the development of the tertiary industry to maintain the vitality of economic development and prevent environmental deterioration.

A dynamic ejection coal burst model for coalmine roadway collapse

In this study,we established a dynamic ejection coal burst model for a coalmine roadway subject to stress,and held that the stress concentration zone at the roadway side is the direct energy source of this ejection.The formation and development of such burst undergoes three stages:(1)instability and propagation of the cracks in the stress concentration zone,(2)emerging of a layered energy storage structure in the zone,and(3)ejection of coal mass or coal burst due to instability.Moreover,we figured out the initial strength of periodic cracks is parallel to the maximal dominant stress direction in the stress concentration zone and derived from the damage strain energy within the finite area of the zone based on the Griffith energy theory.In addition,we analyzed the formation process of the layered energy storage structure in the zone,simplified it as a simply supported restraint sheet,and calculated the minimum critical load and the internally accumulated elastic energy at the instable state.Furthermore,we established a criterion for occurrence of the coal burst based on the variational principle,and analyzed the coal mass ejection due to instability and coal burst induced by different intensity disturbances.At last,with the stratum conditions of Junde Coalmine as the model prototype,we numerically simulated the load displacement distribution of the stress concentration zone ahead of the working face disturbed by the main roof-fracture-induced dynamic load during the mining process as well as their varying characteristics,and qualitatively verified the above model.

Composite active control system of roof and side truss cable for large section coal roadway in fold coal pillar area

In order to solve the surrounding rock control problem of large section gangue replacement roadway under complicated conditions, this paper analyzed the impact to the roadway controlling produced by the geological conditions such as high ground stress, folded structure tilted roof asymmetry and soft wall rock, and built the tilt layered roof structural mechanics model to clarify the increase span mechanism of the weak coal instability. Then, we proposed the combined control system including roof inclined truss cable, coal-side cable-channel steel and intensive bolt support. And then by building the structural mechanics model of roof inclined truss cable system, the support principle was described. Besides, according to this model, we deduced the calculation formula of cable anchoring force and its tensile stress. Finally surrounding rock control technology of large section roadway in fold coal pillar area was formed. Field practice shows that the greatest roof convergence of gangue replacement roadway is 158 mm and coal-side deformation is 243 mm. Roadway deformation is controlled effectively and technical support is provided for replacement mining.

Technological anxiety:Analysis of the impact of industrial intelligence on employment in China

Employment is the greatest livelihood.Whether the impact of industrial robotics technology materialized in machines on employment in the digital age is an“icing on the cake”or“adding fuel to the fire”needs further study.This study aims to analyze the impact of the installation and application of industrial robots on labor demand in the context of the Chinese economy.First,from the theoretical logic and the economic development law,this study gives the prior judgment and research hypothesis that industrial intelligence will increase jobs.Then,based on the panel data of 269 cities in China from 2006 to 2021,we use the two-way fixed effect model,dynamic threshold model,and two-stage intermediary effect model.The objective is to investigate the impact of industrial intelligence on enterprise labor demand and its path mechanism.Results show that the overall effect of industrial intelligence on the labor force with the installation density index of industrial robots as the proxy variable is the“creation effect”.In other words,advanced digital technology has created additional jobs,and the overall supply of employment in the labor market has increased.The conclusion is still valid after the endogeneity identification and robustness test.In addition,the positive effect has a nonlinear effect on the network scale.When the installation density of industrial robots exceeds a particular threshold value,the division of labor continues to deepen under the combined action of the production efficiency and compensation effects,which will cause enterprises to increase labor demand further.Further research showed that industrial intelligence can increase employment by promoting synergistic agglomeration and improving labor price distortions.This study concludes that in the digital China era,the introduction and installation of industrial robots by enterprises can affect the optimal allocation of the labor market.This phenomenon has essential experience and reference significance for guiding industrial digitalization and intelligent transformation and promoting the high-quality development of people’s livelihood.

An Application of Dynamic Structure Model to SoilCorrosion Research

Soil corrosion is a complex system which is difficult to be simulated with mathematicalmodels. Taking the mountainous areas in western henan Province as an example, this paper describesthe application of dynamic structure model to soil corrosion analysis. The primary component factors ofthe soil corrosion system and the causality of the factors are determined in this paper. The interactiverelations of the systematic variables is established with delphi method. The dynamic structure modelis selected to make the forecast of the soil corrosion system, the analysis of sensitivity of the variablesand the analysis of the system control.

Development of a distribution management system in refinery industry

Developing an information system for managing the product distribution in a refinery demands sophisticated design solutions. First, organization models are created to describe the structural relationships among employees and the ways in which they will use the information system. Second, function models are created to hierarchically describe how sales, transports, deliveries and vehicles are managed. Thirdly, an information model is built to represent the data entities and their dynamic interactions. Based on the system design, a distribution management system is developed and implemented in a refinery, which has considerably increased the distribution management efficiency and effectiveness.

Mutual optimization of water utilization structure and industrial structure in arid inland river basins of Northwest China

Water is a key restricting factor of the economic development and eco-environmental protection in arid inland river basins of Northwest China. Although water supplies are short, the water utilization structure and the corresponding industrial structure are unbalanced. We constructed a System Dynamic Model for mutual optimization based on the mechanism of their interaction. This model is applied to the Heihe River Basin where the share of limited water resources among ecosystem, production and human living is optimized. Results show that, by mutual optimization, the water utilization structure and the industrial structures fit in with each other. And the relationships between the upper, middle and lower reaches of the Heihe River Basin can be harmonized. Mutual benefits of ecology, society and economy can be reached, and a sustainable ecology-production-living system can be obtained. This study gives a new insight and method for the sustainable utilization of water resources in arid inland river basins.

The Influence of the Urban-Rural Income Disparity on the Industrial Structure—Taking the Yangtze River Delta Region as an Example

In this paper, the effect of the mediation effect is mainly used to test and analyze the regression model, and most scholars have studied the impact of the modernization of the industrial structure on the income gap. However, this paper is from another perspective, based on the social background of high-quality development, the main study is the impact mechanism of urban and rural income gap on the industrial structure, taking the Yangtze River Delta as the main research object, and specifically selecting 22 central cities in the Yangtze River Delta region, which is also one of the highlights of this study. The regression model is constructed by using the intermediary effect, and the four intermediary variables of fiscal expenditure (M1), fixed asset investment (M2), number of patent applications (M3), and total import and export (M4) are selected, which represent the role of the government, fixed asset investment, scientific and technological level and opening-up level, and study and analyze the inherent influence mechanism between each variable. Before doing specific research, I consulted the papers and literature of many other outstanding scholars, among which Cheng Yuhong and Cheng Chi’s “The Influence Mechanism of industrial structure of urban and rural income gap” [1] has great reference value for this paper. According to the research results, under the background of high-quality development in the Yangtze River Delta region, the expansion of the income gap between urban and rural areas will inhibit the upgrading of the industrial structure, so it is necessary to focus on building a new type of urbanization, accelerating the construction of an urban innovation system, optimizing the rural employment structure to narrow the income gap between urban and rural areas, and providing impetus for the continuous upgrading of the industrial structure.

京津冀科技创新投入对产业结构高级化的影响

京津冀科技创新对于推动京津冀地区产业结构高级化提供了有力支撑。通过明确京津冀科技创新投入对产业结构高级化影响的被解释变量、解释变量和控制变量,确定京津冀科技创新投入对产业结构高级化影响的指标。构建京津冀科技创新投入对产业结构高级化影响的静态回归模型和动态回归模型,利用2009—2020年面板数据,深入开展京津冀地区科技创新投入对产业结构高级化影响的对比研究。结果表明:京津冀整体的科技创新投入对其产业结构高级化的影响显著,科技创新投入增加能显著促进产业结构高级化;京津冀科技创新投入对产业结构高级化的影响程度存在显著的空间差异,经济发展水平显著影响地区科技创新投入对产业结构高级化的促进力度;考虑控制变量,区域对外开放水平显著抑制地区产业结构高级化,人力资本水平与政府支持力度对地区产业结构高级化影响存在显著空间差异。根据研究结果,提出京津冀科技创新推动产业结构高级化的对策建议。

数字普惠金融赋能县域产业结构转型升级的动力机制——基于PLS-SEM模型分析

基于偏最小二乘法结构方程模型(PLS-SEM),运用河南省县域2014—2020年平衡面板数据研究数字普惠金融驱动河南省县域产业转型升级的机制与实证效果,结果表明:数字普惠金融能够推动河南省县域产业结构的转型升级;数字普惠金融主要通过经济发展、生态环境、社会共享三个方面共同推动河南省县域产业结构转型升级;从发展潜力方面看,数字普惠金融对产业结构升级有一定负相关性,可能的原因是河南省县域数字平台不够完善、数字信息技术落后,且大多以轻工业、农业为主,导致数字普惠金融的正向融入性存在延迟。必须持续推动数字普惠金融的产业融入性、夯实数字普惠金融服务实体经济的功能性,提高河南省县域产业经济韧性。

体育产业发展与区域产业结构升级的动态关系研究——基于VAR模型和脉冲响应的实证检验

运用2008-2017年体育产业增加值、产业结构层次系数,通过协整分析、误差修正模型、格兰杰因果关系检验、脉冲响应函数和方差分解法,实证检验体育产业发展与区域产业结构升级之间的相互作用。结果显示:体育产业发展与区域产业结构升级之间存在长期均衡关系,同时两者间具有正向促进作用;从短期来看,两者的增长除了受上一期自身发展的影响外,相互间存在正向促进作用;二者之间存在单向因果关系,即体育产业发展是区域产业结构升级的格兰杰原因;当体育产业受到冲击时,表现为“短期效应强,长期效应弱”;当区域产业结构受到冲击时,表现为“短期效应弱,长期效应强”;二者的发展以自身内在驱动力为主,体育产业发展对区域产业结构升级的影响具有“滞后效应”。

PPP旧工业区再生利用项目动态利益分配——基于阶段性风险的Shapley修正模型

PPP旧工业区再生利用项目风险系统具有明显的阶段性,相应地影响各阶段利益分配模式.将PPP旧工业区再生利用项目全寿命周期划分为前期阶段、施工阶段与运维阶段,通过文献调查法与专家访谈法识别项目各阶段风险因素,构建动态风险因素指标体系;为使风险计算结果更有意义,将主客观赋权相结合,采用专家打分法和熵权法确定各阶段风险因素权重,建立PPP旧工业区再生利用项目基于阶段性风险因素修正的Shapley动态利益分配模型.从实用角度将某钢厂设计创意产业园与模型建立相结合,以期为类似项目参考借鉴.

京津冀产业结构优化对碳排放的影响研究——基于动态面板的系统GMM模型和VAR模型

京津冀地区作为国家重点战略发展区域,其低碳发展、产业结构优化升级在中国的低碳产业发展中举足轻重,各产业的碳减排成效对地区减排目标的实现具有重要意义。论文利用动态面板的系统GMM模型分析2000—2017年京津冀区域的产业结构合理化与高级化对碳排放的影响程度,构建VAR模型具体分析京津冀三地的产业结构合理化与高级化对碳排放的影响差异,采用多方程联立的形式回归分析相关经济变量间的逻辑因果关系以及短期冲击效应。研究结果表明:1)京津冀地区整体产业结构高级化与合理化会降低碳排放;2)京津冀三地的产业结构的高级化与合理化水平分别对本地区的碳排放影响存在差异。最后,基于京津冀地区产业结构优化对碳排放的影响,分别对各地区的碳减排提出相关政策建议。

智慧矿山工业广场三维自动建模技术研究

为打破煤矿工业广场建模模式目前存在的高度依赖人工操作的现状,实现数字矿山规模化规范化建设、煤矿地面建筑设备模型量产化。本文对煤矿工业广场生产建筑群进行空间结构分析,着重分析煤矿井口、煤矿车间、煤矿办公楼的几何空间结构及生产设施的空间几何构型元素,提出一种分体分面组合模型自动建模技术。首先,通过将复杂的生产建筑群进行个体解构和几何拆分,将整套地上生产线设备及建筑拆分为最小规则(不规则)几何单元体,构建顶视投影弧段索引拓扑图;其次,通过线性封闭弧段环高程拉伸生成几何体空间组合关系构建建筑群;最后,以灵新煤矿为实验区域进行验证。结果表明:本文方法能够模拟建筑结构与设备的几何独特性,且纹理外观满足数字化要求;总建模工时由原来的每10栋建筑3.25人天降低到0.78人天,产能提升达到预期。

薄壁四点接触球轴承-腕部关节系统接触动力学分析

在机器人实际工况中,针对含有薄壁四点接触球轴承的机器人腕部关节系统的运动稳定性问题,对腕部系统模型进行了简化设计和仿真研究。在考虑薄壁结构的弹性变形和动态接触作用耦合影响的基础上,建立了刚柔耦合工业机器人腕部关节系统模型,分析了不同受载工况和正反转驱动下的变形规律和动态特性。首先,基于多体动力学和Hertz接触理论,设计了包含薄壁四点接触球轴承和中空轴及基座的腕部关节系统刚柔耦合接触动力学仿真模型;然后,考虑薄壁中空轴、基座、轴承套圈和保持架的结构弹性变形、钢球和套圈滚道、保持架的动态接触作用,研究了机器人腕部关节系统两种实际工况对保持架和钢球角速度、保持架和薄壁基座振动位移、钢球与套圈的动态接触力的影响;最后,计算分析了两种工况下腕部关节系统的动态载荷规律和振动响应特性。研究结果表明:在相对较大的径向载荷作用下,保持架和钢球会出现打滑现象,速度呈现周期波动,保持架和基座具有更好的运动稳定性,其薄壁轴承内部载荷降低,主副接触对均承担联合载荷,轴承内部载荷稳定性也更好。该仿真模型及结果可以为薄壁腕部关节系统的动力学分析与设计提供参考。

瘦煤化学结构表征及分子模型构建

为了高效清洁利用高阶煤,以瘦煤为研究对象,通过X射线光电子能谱(XPS)和固体核磁共振碳谱(^(13)C NMR)实验表征方法对瘦煤的元素赋存形态以及碳原子结构进行了表征分析,构建了瘦煤大分子模型,并对其进行结构优化。结果表明:瘦煤分子的芳香结构由1个萘、8个蒽、1个四连苯、1个芘、2个吡啶、2个吡咯以及1个噻吩构成;含氧结构包括2个环内氧接脂碳,2个氧取代芳碳以及1个羰基碳;脂肪烃则由2个脂甲基、3个芳甲基、2个亚甲基以及4个次甲基组成;最终构建的瘦煤大分子模型为C_(200)H1_(40)O_(5)N_(4)S;初始模型经优化后,煤分子的价电能和非键能都有所下降,但最终模型中煤分子的价电子能比非键能要高,是总能量的主要部分;从煤表面对不同气体所能提供的吸附空间角度来讲,煤中CO_(2)气体的吸附优势要强于CH_(4)气体。

基于ESDA的中国西部省域产业结构的实证分析

通过在全域和局域内进行检验,表明西部省域产业结构间存在空间依赖性,提出了研究产业结构变化的空间误差模型,对西部12省域产业结构变动进行了空间计量回归。结果显示,西部省域产业结构间存在明显的空间依赖性;产业结构的初始值、人均GDP、全社会固定资产投资等因素对产业结构变化的影响具有显著的空间变异现象,说明这些因素对产业结构的影响存在显著差异的原因是所在区域的不同。基于此两点,得出结论:西部12省区应该作为一个系统整体分析,纳入空间依赖性要素,结合相邻省域的产业结构状况来考虑推进省域产业结构的高度化,针对性地提出促进西部省域产业升级的对策建议。

广东省人力资本与产业结构空间优化互动的实证研究

本文选用广东省21个城市2013—2022年面板数据,利用空间计量模型对广东省人力资本水平与产业结构之间的空间关联进行分析。结果显示:考察期人力资本水平和政府调控并不利于广东省产业结构水平优化,而经济开放度、基础设施和金融支持则呈现出显著正向影响。最后,本文提出了针对不利因素与有利因素不同影响的政策建议。一方面,强调差异化教育、行业导向培养、灵活用工等措施,以促进更为平衡和可持续的产业结构升级;另一方面,提出整合产业政策、拓展合作和强化基础设施建设以最大程度地发挥各项因素的积极作用,实现产业结构的升级和优化。这些发现和建议为深入理解广东省人力资本与产业结构互动提供了有力的理论支撑和政策指导。

山东省金融发展对产业结构升级的动态影响——基于VAR模型的实证分析

针对山东省金融发展对产业结构升级的动态影响的问题,选用VAR模型基于1979-2014年的数据进行实证分析,结果表明:金融发展、产业结构合理化与产业结构高级化之间存在长期稳定的协整关系,但并不存在双向格兰杰因果关系,金融发展与产业结构升级之间没有形成良性互动发展机制。在短期内,金融规模的扩张能促进产业结构升级,但存在时滞性与长期推动力不足等问题:金融效率的提高无论在短期还是长期均不能促进产业结构升级,山东省金融资源错配导致的金融资本配置效率低下是造成这种现象的根源所在。

重庆市高端制造业产业结构与竞争力评价——基于动态偏离-份额Esteban模型

运用动态偏离-份额Esteban模型对重庆市2007—2016年高端制造业的产业结构和竞争力进行定量分析。分析结果表明:交通运输设备制造业、医药制造业和电气机械器材制造业的产业结构较为合理,且具有一定的产业竞争力,是重庆市高端制造业发展的中坚力量;剩余三大产业只有通信与计算机设备制造业有一定的竞争力,其他产业都展现出结构不合理和缺乏竞争力。