Transnational Economic Connection Analysis Based on Railway Class Accessibility Between China and Russia

Under the background of ‘the Belt and Road’ initiative, the economic cooperation has great potential between China and Russia. The railway accessibility has an important influence on the economic connections of cities along the railway line. This paper studied the Sino-Russian transnational economic connection based on the railway class accessibility along Trans-Siberian railway(the transnational China railway branch line). The results are as following. First, the railway accessibility of the Chinese nodes is stronger than that of the Russian nodes, which in general displays a tendency of space attenuation from China to the Sino-Russian border, then to Russia. Spatially, the railway accessibility within the study area shows a ‘High East, Low West’ and ‘High South, Low North’ spatial pattern. The railway accessibility of the nodes, which are located at the beginning and end of the railway line, is weaker than those nodes located in the middle of the line. Second, the railway accessibility and external economic connection intensity summation of the nodes show a positive relationship along the railway line. The economic connection intensity summation of different nodes presents obvious regional differentiation. Finally, as economic connection network has evolved, the small world effect of Sino-Russian railway economic connection network becomes strong.

Performance-Economic and Energy Loss Analysis of 80 KWp Grid Connected Roof Top Transformer Less Photovoltaic Power Plant

In India most part receives 4 - 7 kWh of solar radiation per square meter per day with 200 - 250 sunny days in a year. Tamilnadu state also receives the highest annual radiation in India. In this paper, the grid connected photovoltaic plant has a peak power of 80 KWp supplies electricity requirement of GRT IET campus during day time (7 hrs) and reduces load demand and generates useful data for future implementation of such PV plant projects in the Tamilnadu region. Photovoltaic plant was installed in April 2015, monitored during 6 months, and the performance ratio and the various power losses (power electronics, temperature, soiling, internal, network, grid availability and interconnection) were calculated. The PV plant supplied 64,182.86 KWh to the grid from April to September 2015, ranging from 11,510.900 to 10,200.9 kWh. The final yield ranged from 143.886 (h/d) to 127.51 (y/d), reference yield ranged from 201.6 (h/d) to 155.31 (h/d) and performance ratio ranged from 71.3% to 82.1%, for a duration of six months, it had given a performance ratio of 83.82%, system efficiency was 4.16% and the capacity factor of GRT IET Campus for six months was 18.26%. Payback period in years = 9 years 4 months, energy saving per year = 204,400 KWh, cost reduction per year = 1,737,400, Indian rupee = 26,197.30 USD and total CO2 reductions per year = 102,200 tons CO2/year.

Mechanical Experimental Study on Tensile Bolted Connections of Cross-laminated Timber

In order to explore a kind of high-strength,earthquake-resistant,eco-nomical and suitable connection,4 groups of cross-laminated timber wall-to-floor and wall-to-wall bolted connections were tested under monotonic and cyclic load-ing.The defommation characteristics and failure modes of the cross-laminated tim-ber wall-to-floor and wall-to-wall bolted connections were exploited.Load-slip curves,bearing capacity,yielding point,stiffness and ductility of each group of specimens were analyzed.The test results indicate that the loading process of cross-laminated timber bolted connections under tension can be categorized as five stages,namely the elastic stage,the slip stage,the embedding stage,the yield-ing stage and the ultimate stage.The ultimate tensile capacity of cross-laminated timber bolted wall-to-floor connections is 2.67 times that of the wall-to-wall bolted connections.Compared with cross-laminated timber self-tapping screwed connections,the ultimate tensile capacity of the cross-laminated timber wall-to-floor bolted connections is 2.70 times that of the self-tapping screwed connec-tions,and the ultimate tensile capacity of the cross-laminated timber wall-to-wall bolted connections is 3.83 times that of the self-tapping screwed connections.The crosslaminated timber bolted connections have larger yielding displacement and wider plastic range,and they are more energy dissipative and more ductile.Furthermore,the cost of the cross-laminated timber wall-to-floor bolted connec-tions is 46%that of the self-tapping screwed connections,while the cost of cross-laminated wall-to-wall bolted connections is 53%that of the self-screwed connections.

Research on Sustainability of China’s Economic Cooperation With Africa

Africa is one of the important polars in the current political and economic pattern of the world.This paper explores the problems in China’s economic cooperation with Africa from the perspective of Chinese-funded enterprises in Africa being pioneers and barometers in the cooperation,and researches sustainable development of China’s economic cooperation with Africa focusing on connectivity and integrating African characteristic.

Analysis on Economic Resilience of the Guangdong-Hong Kong-Macao Greater Bay Area:A Perspective from the Economic Connection Network

In the face of an increasingly complex and unstable external development environment,enhancing economic resilience has become a key task in the construction of the Guangdong-Hong Kong-Macao Greater Bay Area.This paper analyzes the changes in the economic resilience of the Guangdong-Hong Kong-Macao Greater Bay Area and its constituent cities after the 2008 global financial crisis by virtue of the regional economic resilience assessment method proposed by Martin et al.It constructs an economic connection network for the Guangdong-Hong Kong-Macao Greater Bay Area using the data from corporate headquarters and branches of A-share listed companies to analyze its impact on the economic resilience of the Area.The study reveals the three following conclusions.Firstly,the economic resilience of the Guangdong-Hong Kong-Macao Greater Bay Area generally outperforms the national average level,seeing a rapid boost over the recent years and exceeding the level witnessed during the 2008 financial crisis.However,there are marked disparities in the economic resilience ofvarious cities within the Greater Bay Area,with Shenzhen,Guangzhou,and Dongguan emerging as the most robust in this regard.Secondly,the economic connection network has a positive impact on the economic resilience of the cities in the Guangdong-Hong Kong-Macao Greater Bay Area.Specifically,there is a positive correlation between a city's economic resilience and its centrality in the economic connectionnetwork.Suchcentrality exerts a positive spillover effect on the economic resilience of surrounding cities.Thirdly,from the perspective of industryspecific networks,circulation and service industry networks are more conducive to improving the economic resilience of a city.Given the significant role of the economic connection network in shaping regional and urban economic resilience,it is imperative for the Guangdong-Hong Kong-Macao Greater Bay Area to prioritize ensuring economic development security and enhancing economic resilience,promote the development of the economic connection network,and enhance the network centrality of its constituent cities.This can improve the economic resilience of itselfand its constituentcities inaneffective manner.

考虑并网灵活性的大规模海上风电场集群接入系统规划研究

为了提升大规模海上风电场集群接入系统的并网灵活性,提出了一种考虑并网灵活性的大规模海上风电场集群接入系统规划方法。首先,通过构建综合考虑并网灵活性及经济性的大规模海上风电场集群接入系统规划的多目标优化模型,挖掘大规模海上风电集群输电系统的灵活性;其次,采用运用改进的非支配排序遗传算法与基于图论的拓扑修复策略,对多目标优化模型进行求解,再次,基于模糊隶属度分析,从求出的帕累托前沿解中提取得到经济性、灵活性最优的风电场集群接入方案;最后以实际海上风电场群并网的算例为例进行分析,验证所提方法的有效性和可行性。

中蒙俄K3/K4次国际班列对沿线城市可达性的影响

以中蒙俄铁路K3/K4次班列沿线节点城市和区域为研究对象,分析了其节点城市与区域的可达性,并计算了节点城市之间的经济联系强度。结果表明,节点城市时间可达性呈现两端高、中间低的趋势,与节点城市到目的地城市的出行时间成正比;节点城市的经济可达性呈现两端低、中间高的趋势;K3/K4班列沿线有4个较明显的经济中心区,且中国城市之间的经济联系强度和俄罗斯西部城市之间的经济联系强度较高,此外中国与蒙古国之间的经济联系弱于蒙古国与俄罗斯之间的经济联系。受边境检查和转向架更换情况的影响,中蒙边境的二连浩特、扎门乌德和蒙俄边境的苏赫巴托尔、纳乌什基在上述计算结果中均表现出明显的特殊性。

包容性增长视域下数字经济高质量发展的路径研究

随着新一轮科技革命与产业升级的不断深化,数字经济逐渐成为推动经济复苏和增长的重要引擎。然而,数字经济在高速发展的同时也带来了一系列挑战,如“数字鸿沟”的扩大、数字治理不完善、数字贸易壁垒等问题,不利于经济社会的稳定和可持续发展。为此,本文从包容性增长视角分析当前数字经济发展存在的问题,揭示数字经济发展与包容性增长的内在联系,探讨数字经济高质量发展的路径,旨在稳步推进中国共同富裕取得更为明显的实质性进展,实现经济社会公平和可持续发展。

成渝地区双城经济圈物流空间联系及其网络结构研究

区域物流对经济发展至关重要。为揭示当前成渝地区双城经济圈(以下称成渝地区)物流联系强度及其网络空间结构,本文基于地理空间联系视角,在2009—2019年研究期间以成渝地区16个地级及以上城市为研究对象,采用引力模型构建成渝地区物流网络,通过社会网络分析法测算网络密度、网络中心度以及凝聚子群,进而对其联系强度、空间布局等进行深入分析。结果表明:在本研究时间范围内,成渝地区城市物流质量水平空间分异显著,物流联系强度差异大;网络密度从0.9023升至0.9042,处于较高密度水平,波动幅度小,聚合度强,物流联系密切,但成渝地区内部网络密度失衡,中部密度最高,北部密度较中部稍低,西部密度最低;整体上物流网络呈现以成都、重庆为核心相向发展的放射状网络结构。

职业教育服务区域经济发展的时代转向、内在逻辑与协同路径

新时代的职业教育在服务国家产业转型升级、区域经济高质量发展中扮演着不可或缺的角色:在定位转向上,职业教育的独立性渐强;在目的转向上,职业教育的地位更高;在转向功能上,职业教育的作用性明显。区域经济与职业教育之间始终存在着动态耦合的作用与反作用,要通过扎根在地化、发挥融合性、提升培养力和注重传承性,进而打通专业衔接链、深化校企合作链、夯实人才输出链和优化工匠培养链,实现职业教育与区域经济高质量协同发展。

克拉运河“通权论”

面对亚欧地区冲突不断、大国博弈加剧这一形势,中国是否应主导或介入修建克拉运河,国内外尚存较大争议。不可否认,“一带一路”倡议的稳步推进为克拉运河项目的开展提供了机遇。从克拉运河和“一带一路”倡议间的互动关系来看,要在百年未有之大变局背景下推进克拉运河项目的建设,应审慎平衡海洋战略考量,关注周边国家的权力动态及其对地区政策制定与合作策略的影响。进一步以“通权论”为理论基础,为未来克拉运河的修建和运营提供指引方向与参照体系。可以预见的是,克拉运河的建设不仅是区域合作与经济互联互通的工具,更是推动亚太命运共同体建设的战略举措。基于此,中国应积极参与克拉运河项目的建设与实施,提升我国在亚太地区的话语权,以期为我国扩展地缘战略空间提供参考。

基于辐射效应的粤港澳大湾区旅游经济结构演变研究

粤港澳大湾区发展区域旅游能够助力打造宜居宜业宜游生活圈,使其拥有更强且更持续的旅游经济影响力。基于旅游辐射效应理论,运用动态因子分析评价11个城市旅游竞争潜力作为辐射效应发挥的基础,通过引力模型对大湾区旅游经济联系进行探讨,分析2014-2021年旅游辐射潜力变化特征及原因。结果表明:①在竞争潜力方面,广港澳深4个城市8年因子得分加总为正,其中广州和深圳基础辐射能力相对稳定,中国香港和中国澳门基础辐射能力受到发展韧性不足的影响;②在辐射潜力方面,粤港澳大湾区多中心发展趋势显著,东莞和佛山发挥着“承上启下”的次中心城市功能,但辐射结构的不对称性,以及竞争与辐射潜力之间的不协调性也同样突出;③对主要旅游城市辐射能力的分析表明,目前粤港澳大湾区内已经形成“广-佛-江-肇”“深-港-莞-惠”“澳-珠-中-江”“广-莞-惠”“澳-港”5条主要的辐射纽带。

大跨度悬空连梁叠合预制施工技术研究

为解决高空大跨度悬空连梁施工作业的安全和成本问题,文章结合工程实际情况,对比多种施工工艺形式,提出了将连梁优化为叠合梁,采用悬挑三角支撑防护一体架进行支撑施工研究。实践表明,采用该技术可以有效解决大跨度高空连梁施工难度大、费用高、工期长等问题,创造了较好的经济和社会效益,为类似高空大跨度悬空连梁施工提供了一种新思路。

智能网联车辆节能自适应巡航控制研究

现有车辆自适应巡航控制多专注于单一的轨迹跟踪目标,而决定控制技术实际应用效益的关键是系统的节能性能.为了能够同时保证跟踪误差收敛性与燃油经济性,研究了一种车辆节能自适应巡航控制器设计方法:首先以轨迹跟踪为目标,设计了具有时变反馈增益的状态反馈控制律;其次,以反馈增益为优化变量,以整个预测时域内各采样时刻自身车辆单位位移燃油消耗量的累加为代价函数,基于经济模型预测控制方法设计了节能控制算法,并通过构建共同Lyapunov函数,给出了保证跟踪误差以指数速度收敛的反馈增益选取范围;最后,通过数值仿真验证了控制器设计的有效性,定量展示了本文所提出的方法在降低燃油消耗量方面的有效性.

巩固脱贫攻坚成果同乡村振兴有效衔接案例分析——基于洛川县苹果产业发展的思考

党的二十大报告指出,全面建设社会主义现代化国家,最艰巨最繁重的任务仍然在农村。我国目前正处于巩固脱贫攻坚成果同乡村振兴有效衔接的关键期,坚持农业农村优先发展,加大特色产业转型升级力度,对巩固拓展脱贫攻坚成果,全面推进乡村振兴具有重要意义。选取洛川县苹果产业实地调研,通过问卷调查、走访农户搜集数据,利用定量研究方法对当地经济发展与脱贫成效满意度进行深入分析,有利于进一步阻断返贫风险,助推洛川县特色生态产业的健康发展,也为巩固拓展脱贫攻坚成果同乡村振兴有效衔接提供了新的发展思路。

公路交通可达性与旅游经济联系空间耦合研究——以湖南省为例

利用加权平均旅行时间模型、引力模型和空间自相关模型对湖南省公路交通可达性与旅游经济联系的空间耦合关系进行分析,结果表明:湖南省公路交通可达性空间分布具有显著的“核心-边缘”特征,呈现出中部高、南北低的特点;湖南省旅游经济联系总量的空间分布呈现以长沙为核心的“中心-外围”圈层结构特征,长沙市旅游经济联系总量具有绝对优势;湖南省公路交通可达性与旅游经济联系耦合协调程度总体上处于中高水平,但极化特征明显,呈现出核心极化和“中心-外围”的特征;两系统空间关联呈现显著的全局正向空间集聚特征。并从完善路网建设、消除地区贸易壁垒、优化旅游空间结构、加强政策引导等方面提出了相关对策建议。

基于二层邻居牵制一致性的并网微电网经济优化控制方法

为提高并网微电网系统经济优化响应速度,降低整体发电运行成本,提出二层邻居牵制一致性算法。该算法将成本微增率(incremental cost rate,ICR)定义为状态变量,引入功率偏差消除项快速消除总功率偏差,利用二层邻居项和牵制项实现快速收敛于最优ICR,计算得到各分布式电源(distributed generation,DG)的最优有功出力参考值。随后提出基于二层邻居牵制一致性的并网微电网经济优化控制方法。该方法基于构建的三层分布式分层架构,第一控制层为双闭环反馈的下垂控制,第二控制层采用电压频率优化控制,稳定系统的频率和电压,第三控制层将各DG最优有功出力参考值输出到P/f下垂控制层,从而实现系统经济优化以及负荷功率供需平衡的目标。最后搭建8个DG并联运行系统仿真模型进行仿真实验。仿真结果表明,所提方法能完成有功出力的经济分配,且系统响应性能优,在负荷突增、功率越限、分时电价、拓扑切换、计及线路损耗、即插即用等因素影响系统运行时,所提方法能使微电网快速达到经济优化状态。

成渝地区双城经济圈旅游经济联系强度与空间结构演变

旅游经济联系是旅游空间结构形成的重要影响因子,旅游空间结构演变规律是旅游经济联系强度变化的结果。首先,本文选择成渝地区双城经济圈作为研究区域,以2015—2019年的旅游经济数据为基础,使用旅游经济联系模型测算旅游经济联系强度。其次,从网络密度、网络中心度、核心—边缘结构、结构洞等方面分析旅游经济空间结构的时空演变格局。最后,文章从提升交通可达性、旅游资源特色化营销、开发特色旅游产品等方面提出成渝地区双城经济圈旅游经济发展的建议,以供参考。

城市群功能联系网络对绿色经济效率的影响

选取2015—2019年中国19个城市群中217个地级市的城市面板数据,采用经济流联系、信息流联系、交通流联系的方法构建了城市群功能联系网络,并应用超效率SBM模型构建了绿色经济效率指标体系,分析了城市群功能联系网络对绿色经济效率的影响以及二者的时空演变特征。研究发现,绿色经济效率整体呈逐步上升趋势,但增速缓慢,不同发展阶段城市群的绿色经济效率存在显著差异;在功能联系上,经济流、信息流和综合流都对提绿色经济效率表现出正向效应,其中信息流强度处于上升趋势;交通流虽然对绿色经济效率的直接影响不显著,但在发展壮大和优化升级阶段发挥了更积极的作用。因此,在推动城市群绿色可持续发展过程中,应注意加强城市群功能联系网络的内在协同;充分发挥信息技术的催化作用;精准实施差异化策略。

考虑源-荷不确定性的微能源网日前鲁棒优化调度

微能源网集成园区/社区的分布式能量系统、多元荷载及控制装置,能够实现多能源联产联供功能,有利于提升各类能源网络运行灵活性和经济性。为有效应对微能源网内部负荷和新能源出力的不确定性,首先建立多面体不确定集刻画负荷和光伏出力波动情况,构建描述微能源网网络拓扑和能流耦合关系的能源集线器(energy hub,EH)耦合矩阵。然后,以最小化系统运行成本为目标建立微能源网在并网和孤岛运行模式下的两阶段鲁棒优化经济调度模型,并运用线性决策规则(linear decision rule,LDR)和对偶理论制定模型求解策略。最后,基于IEEE 33节点配电网改进设计的微能源网进行算例验证分析。结果表明,LDR能够在一定精度范围内通过线性仿射函数有效近似刻画决策变量和不确定变量间的关系,降低两阶段鲁棒优化经济调度模型的求解难度。