Adaptive fuze-warhead coordination method based on BP artificial neural network

The appropriate fuze-warhead coordination method is important to improve the damage efficiency of air defense missiles against aircraft targets. In this paper, an adaptive fuze-warhead coordination method based on the Back Propagation Artificial Neural Network(BP-ANN) is proposed, which uses the parameters of missile-target intersection to adaptively calculate the initiation delay. The damage probabilities at different radial locations along the same shot line of a given intersection situation are calculated, so as to determine the optimal detonation position. On this basis, the BP-ANN model is used to describe the complex and highly nonlinear relationship between different intersection parameters and the corresponding optimal detonating point position. In the actual terminal engagement process, the fuze initiation delay is quickly determined by the constructed BP-ANN model combined with the missiletarget intersection parameters. The method is validated in the case of the single-shot damage probability evaluation. Comparing with other fuze-warhead coordination methods, the proposed method can produce higher single-shot damage probability under various intersection conditions, while the fuzewarhead coordination effect is less influenced by the location of the aim point.

Measurement for coordinated development of＂four modernizations＂ and its efficiency ofprefecture level cities or above in China

The efficient and coordinated development of industrialization, urbanization, informatization and agricultural modernization(so called 'Sihua Tongbu' in China, and hereinafter referred to as 'four modernizations') is not only a practical need but also an important strategic direction of integrating urban-rural development and regional development in recent China. This paper evaluated the comprehensive, coupling and coordinated developmental indices of 'four modernizations' of China's 343 prefecture-level administrative units, and calculated their efficiency of 'four modernizations' in 2001 and 2011. The efficiency evaluation index system was established. The efficiencies and their changing trend during the period 2001–2011 were investigated using the data envelopment analysis(DEA) model. Spatial-temporal pattern of the efficiency of China's prefecture-level units was explored by using exploratory spatial data analysis(ESDA). Finally, the main influencing factors were revealed with the aid of geographically weighted regression(GWR) model. Results indicate that the comprehensive, coupling and coordinated developmental indices and efficiency of 'four modernizations' of China's prefecture-level administrative units have obvious spatial differences and show diverse regional patterns. Overall, the efficiency is relatively low, and only few units with small urban populations and economic scale are in DEA efficiencies. The efficiency changing trends were decreasing during 2001–2011, with a transfer of high efficiency areas from inland to eastern coastal areas. The difference between urban and rural per capita investment in fixed assets boasts the greatest influence on the efficiency.

Dynamic transfer and driving mechanisms of the coupling and coordination of agricultural resilience and rural land use efficiency in China

The joint study of agriculture and rural areas is of great significance for safeguarding agricultural development,revitalizing rural areas,and enhancing farmers'well-being.This paper aims to assess the spatiotemporal evolution characteristics of the coupling and coordination degree of agricultural resilience and rural land use efficiency and their dynamic transfer law and driving mechanisms,based on panel data of 31 provinces(municipalities and autonomous regions)in China from 2010 to 2020.The results showed:(1)Good coupling and coordination of agricultural resilience and rural land use efficiency,with reduced temporal differentiation degrees between regions;(2)Significant spatial autocorrelation between the overall coupling and coordination degrees of agricultural resilience and rural land use efficiency,forming cold spot and hot spot spatial patterns in the western and eastern parts,respectively,with a central transition area;(3)A spillover effect of the dynamic transfer process,with a manifested specific law as"club convergence","Matthew effect",and progressive development characteristics;(4)The key roles of the natural,social,economic,and policy indicators in the coupling and coordination development process of agricultural resilience and rural land use efficiency.However,the selected indicators showed substantial spatial differences in their influences on the coupling and coordination process between provinces.

The Relationship between Water Resources Use Efficiency and Scientific and Technological Innovation Level: Case Study of Yangtze River Basin in China

The Yangtze River Basin’s water resource utilization efficiency(WUE)and scientific and technological innovation level(STI)are closely connected,and the comprehension of these relationships will help to improve WUE and promote local economic growth and conservation of water.This study uses 19 provinces and regions along the Yangtze River’s mainstream from 2009 to 2019 as its research objects and uses a Vector Auto Regression(VAR)model to quantitatively evaluate the spatiotemporal evolution of the coupling coordination degree(CCD)between the two subsystems of WUE and STI.The findings show that:(1)Both the WUE and STI in the Yangtze River Basin showed an upward trend during the study period,but the STI effectively lagged behind the WUE;(2)The CCD of the two subsystems generally showed an upward trend,and the CCD of each province was improved to varying degrees,but the majority of regions did not develop a high-quality coordination stage;(3)The CCD of the two systems displayed apparent positive spatial autocorrelation in the spatial correlation pattern,and there were only two types:high-high(H-H)urbanization areas and low-low(L-L)urbanization areas;(4)The STI showed no obvious response to the impact of the WUE,while the WUE responded greatly to the STI,and both of them were highly dependent on themselves.Optimizing their interaction mechanisms should be the primary focus of high-quality development in the basin of the Yangtze River in the future.These results give the government an empirical basis to enhance the WUE and promote regional sustainable development.

Evaluation of Land-Use Efficiency Based on Regional Scale——A Case Study in Zhanjiang,Guangdong Province

Evaluating land use efficiency is critical to the revision of general land use planning. An assessment indicator system for regional land use efficiency was established in this paper from the aspects of society,economy,ecology and environment. The weight of each indicator was defined by an analytical hierarchy process (AHP) and the entropy method (EM). Then,a case study in Zhanjiang was carried out to analyze the regional land use efficiency from 1996 to 2004 and its development by using the method of multifactor composite evaluation and an analytical model of the de-gree of coordination. The results indicate that land use efficiency with respect to society and the economy improved,whereas the ecological and environmental efficiencies were found to decrease. The degree of coordination in Zhanjiang is still at the status of basic coordination. Finally,measures for enhancing the ecological and environmental establish-ment are suggested in order to improve the regulations of land use structure and patterns,establish ecological forests for the public good and green corridors and prevent the soil erosion.

Understanding the change of land space utilization efficiency with different functions and its coupling coordination: A case study of Urban Agglomeration in the Middle Reaches of the Yangtze River, China

Land spaces function in capacities of urban development,agricultural production,and ecological conservation,among many others.Research of land space utilization efficiency(LSUE)and coupling coordination relationships among its subsystems are significant for sustainable land space development.In this study,taking the Urban Agglomeration in the Middle Reaches of the Yangtze River(UAMRYR)as the study area,we establish a measurement index system to evaluate the LSUE(2000–2018)and analyze its coupling coordination degree by utilizing an improved coupling coordination model.The main results include the following.(1)The average efficiency levels of urban space and agricultural space in the UAMRYR increased 2000–2018,while the average efficiency of ecological space declined.(2)The spatial pattern of the LSUE values varied greatly,with the distributions of high-efficiency and low-efficiency levels significantly different.(3)The coupling degree of LSUE includes three types,i.e.,high-level coupling,break-in,and antagonism.Each coupling degree type was characterized by change over time.(4)The proportion of areas with high coupling coordination and moderate coupling coordination increased from 2000 to 2018,while the proportion of areas with basic coupling coordination,moderate imbalance,and serious imbalance declined during this period.Given that the spatial differentiation of the LSUE and its coupling coordination,it is necessary to implement a differential land space development strategy in the UAMRYR.This study is helpful to promote the efficient utilization and coordinated development of land space utilization systems.

Dynamic Interference Coordination With Analytical Near-Optimal Power Allocation Toward High User Fairness

To mitigate interference on celledge users and improve fairness of the whole system, dynamic inter-cell interference coordination(ICIC) is one of the promising solutions. However, traditional dynamic ICIC is considered as an NP-hard problem and power variability further adds another dimension to this joint optimization issue, making it even more difficult to quickly reach a near-optimal solution. Therefore, we theoretically obtain the closed-form expression of the near-optimal power allocation ratio for users in adjacent cells paired in the same resource block and interfere each other, so that the total utility corresponding to α-fairness is maximized. Dynamic ICIC using this closed-form solution could improve user fairness without causing an increment of the computational complexity. Numerical results show that, compared with the schemes using identical power for different users, our method does not obviously degrade the system's average spectral efficiency.

碳减排“时-空-效-益”统筹理论:Ⅲ.效率统筹

碳减排效率表现为在达成碳减排目标同时尽可能降低社会成本,实现碳减排效率最优的关键在于统筹政府管制与市场机制。作为碳减排“时-空-效-益”统筹理论系列论文的组成部分,构建了效率统筹方法框架,首先阐释了碳减排效率的概念内涵,提出了效率统筹的理论框架;进而采用新制度经济学的理论视角,系统分析了市场机制与政府干预在碳减排过程中的互动机制与互补路径;并结合相对斜率决策准则,应用C3IAM/EcOp模型和CEEPA-CETA-FM模型深入探索了如何在不同减排机制下实现减排资源的优化配置,科学回答了碳减排混合机制的设计问题,为统筹政府管制与市场机制提供方法基础。

合成孔径雷达快速后向投影算法综述

后向投影(BP)算法是合成孔径雷达成像算法发展的重要方向之一。然而,由于BP算法具有较大的计算量,阻碍了其在工程应用上的发展。因此,近年来如何有效地提高BP算法的运算效率受到了广泛的重视。该文讨论了基于多种成像面坐标系的快速BP算法,包括距离-方位平面坐标系、地平面坐标系和非欧氏坐标系。该文首先简要介绍了原始BP算法的原理和不同坐标系对加速BP算法的影响,并对BP算法的发展历程进行梳理。然后讨论了基于不同成像面坐标系的快速BP算法的研究进展,并重点介绍了作者所在研究团队近年来在快速BP成像方面完成的研究工作。最后介绍了快速BP算法在工程上的应用,并展望了未来快速BP成像算法的研究发展趋势。

高质量发展目标下脱贫县农业产业化与农地利用生态效率耦合协调分析:以江西省为例

探究脱贫县农业产业化与农地利用生态效率耦合协调关系,对促进农业高质量发展具有重要意义。基于新发展理念,以江西省25个脱贫县为研究对象,构建农业产业化与农地利用生态效率耦合评价体系,借助耦合协调模型和泰尔指数模型测度两者的耦合协调水平及其区域差异。结果表明:(1)2011—2020年,江西省脱贫县农地利用生态效率总体水平较高,年均值为0.738,赣南地区高于赣中和赣北地区;(2)2011—2020年,江西省脱贫县农业产业化发展指数总体水平较低,年均值为0.414,赣北地区最高,其次为赣中,赣南最低;(3)2011—2020年,脱贫县农业产业化与农地利用生态效率耦合协调指数由期初的0.321升至期末的0.342,总体处于中度失调和轻度失调阶段;(4)脱贫县地区内差异对泰尔指数总体贡献最大,县域农业发展协调性较弱。进一步分析可以发现,市场与政府的作用差异是导致农业产业化水平与农地利用生态效率存在差异的主要原因,综合运用行政和市场手段推动农业产业化发展是提高两者耦合协调水平的关键。

知识产权保护对数字产业创新效率的影响

知识产权保护是提升数字产业创新效率的有力支撑,也是助推创新型国家建设的重要抓手。本文借助渐进式双重差分模型,使用2010~2022年我国上市公司数据考察知识产权保护对数字产业创新效率的影响。结果显示:(1)知识产权保护能够正向提升数字产业创新效率,且随着数字产业创新效率持续提升,知识产权保护的正向驱动效应呈边际递增特征;(2)机制检验结果显示,知识产权保护可通过促进知识溢出、提升技术创新和人力资本水平驱动数字产业创新效率提升;(3)异质性检验结果显示,相较于西部及东北部地区、传媒服务业和国有企业,知识产权保护更能推动东、中部地区、软件开发及信息技术服务业和非国有数字企业创新效率提升。基于此,提出多管齐下健全知识产权保护机制、多路并进提升数字产业创新效率、因地制宜推动数字产业协同发展的对策建议,希冀为提高数字产业创新效率提供相关理论经验。

我国铁路货运效率与绿色物流发展耦合协调研究

铁路货运效率对绿色物流发展有重要影响,通过构建我国铁路货运效率投入产出评价指标体系和绿色物流发展评价指标体系,运用超效率DEA模型和熵权TOPSIS法分别测度2010—2020年我国30个省(市、自治区)的铁路货运效率和绿色物流发展水平,运用耦合协调度模型分析我国铁路货运效率与绿色物流发展耦合协调度,并用障碍度模型进行障碍因子诊断。结果表明:2010—2020年我国铁路货运效率呈先下降后上升态势,绿色物流发展水平呈持续向好态势;铁路货运效率与绿色物流发展耦合协调水平整体呈不断上升趋势,耦合协调等级由勉强协调演变成初级协调,耦合协调度仍有较大优化空间;通过障碍因子分析,发现铁路货运量、人均货物周转量、铁路货物周转量、物流设施用地面积和铁路里程对协调性影响较大。

“双碳”背景下能源消费碳排放效率与生态韧性耦合协调研究

能源系统与生态系统之间存在着相互促进、相互制约等复杂关系,促进能源消费碳排放效率与生态韧性的协调发展对于我国贯彻新发展理念、实现“双碳”战略目标,以及推动经济社会高质量发展均具有十分重要的积极意义。为了深入开展对能源消费碳排放效率与生态韧性的耦合协调度研究,本文以我国30个省份(自治区、直辖市)为研究对象,通过构建能源消费碳排放效率与生态韧性指标体系,运用耦合协调度模型、空间自相关模型以及GM-ARIMA模型,来测度分析和揭示2004—2021年我国30个省份能源消费碳排放效率与生态韧性的耦合协调度及其耦合协调度的时空演变特征,并且还对2022—2026年我国各省份能源消费碳排放效率与生态韧性的耦合协调度做出了预测分析。研究结果表明:1)从整体上看,2004—2021年我国30个省份的能源消费碳排放效率均值与生态韧性均值都分别小于0.6和0.7,耦合协调度类型主要有勉强协调、濒临失调、轻度失调、中度失调4种。2)从时序上看,2004—2021年我国30个省份的能源消费碳排放效率与生态韧性的耦合协调度分别呈现出了波动上升、波动下降、持续下降、平稳不变4种不同的变化趋势。3)从空间上看,2004—2021年我国30个省份的能源消费碳排放效率与生态韧性的耦合协调度均存在着显著的正向空间自相关性,且各省份的局部空间集聚模式都显现得相对平均。4)从预测结果上看,2022—2026年我国30个省份在情景2和情景3的能源消费碳排放效率与生态韧性的耦合协调度值要明显高于情景1,说明降低碳排放强度不但可以有效防治对生态的破坏,而且还能够推动经济社会能源消费结构的转型升级。

中国医疗保障、公共卫生和医疗服务耦合协调研究:精准画像与发展路径

医疗保障与公共卫生、医疗服务耦合协调能促进医疗卫生事业的高质量发展,提高健康治理效能。通过实证研究发现,三个子系统之间发展水平差异大、区域之间发展不均衡,大部分省属于医保滞后型;整体耦合度均值0.49左右,属于总体拮抗水平,反映医疗保障、公共卫生、医疗服务三者之间相互作用、相互影响日益加强,也验证了以人民健康为中心的医疗健康整合发展具有强大内在驱动力。而耦合协调度均值为0.45左右,除北京外,其他地区均处于勉强耦合协调阶段,且耦合协调度低于耦合度,即三个系统相互作用形成的治理合力还不强。未来通过结构性的调整,提高耦合协调度,能有效提升医疗卫生整体效能,突破改革瓶颈。发展选择上呈现出经济拉动型和政策推动型两条路径,经济落后地区在政策推动下提升系统耦合协调度,实现健康促发展的新模式;经济发达地区在经济拉动下,应加快医疗卫生一体化发展,更好地满足人民全生命周期的健康需求。

黄河“几字弯”都市圈土地利用效率与土地生态安全耦合协调研究

通过分析黄河“几字弯”都市圈土地利用效率与土地生态安全的时空演变特征,探索黄河流域土地利用与生态安全协同发展路径。利用Super-SBM模型、投影寻踪模型和耦合协调模型,以2002-2021年黄河“几字弯”都市圈15个城市作为研究对象,分别评估其土地利用效率、土地生态安全水平和二者之间的耦合协调度。结果表明:研究期内土地利用效率良好,平均值0.991,整体呈现逐年下降趋势,空间上以鄂尔多斯为高水平集聚中心;土地生态安全整体水平稳定,平均值为2.012,空间上以鄂尔多斯、榆林为高水平集聚中心;二者耦合协调均值为0.616,整体处于低度协调水平,大部分城市处于濒临失调状态,呈现“中心高,四周低”的空间分布特征。土地利用效率与土地生态安全存在较为明显的矛盾,因此,“几字弯”都市圈内各城市间应优化土地配置,提高土地利用效率,加强城市之间的经验共享与联动发展,共建差异化产业格局,协同推进黄河“几字弯”高质量发展。

黄河流域城市水土资源利用效率的耦合协调时空特征研究

论文利用2009—2020年黄河流域69个城市的面板数据,采用Windows-DEA模型测度城市土地资源利用效率与水资源利用效率,采用耦合协调度模型分析水土资源利用效率之间的协同与冲突,利用莫兰指数模型与空间杜宾模型分析水土资源利用效率协调度的时空演变特征与空间溢出效应,结论如下:(1)黄河流域城市土地资源与水资源利用效率呈现缓慢上升态势,但土地资源利用效率为下游>上游>中游,水资源利用效率为中游>上游/下游。(2)不同城市的水资源利用综合效率出现两极分化现象,但土地资源利用效率则逐步趋于稳态,而且,城市土地资源利用效率始终存在空间邻接的正相关特性。(3)研究时期内大部分城市处于高水平耦合阶段与协调过渡阶段,协调度水平相对较低,2018年前土地资源利用效率与水资源利用效率之间协调度也存在空间邻接的正相关特性。(4)经济增长对本地水土资源利用效率协调度具有促进作用,但对其他城市水土资源利用效率具有抑制作用;三产比重对本地与其他城市的水土资源利用效率协调度也具有相反作用。建议流域内各城市从严从细规划和集约利用水土资源,注重提升整个流域的三产比重与产业升级,保证流域内水土资源利用效率的协同发展。

旅游效率与交通可达性时空演化特征及耦合协调度测算研究以陕西省为例

区域交通可达性的增强对增加旅游人数、刺激旅游消费、提高旅游效率有着正向作用,研究二者之间的相关性对充分释放生产力、提高旅游供给品质具有重要价值。以陕西省为例,对2012—2019年旅游效率及交通可达性的时空演化特征进行分析,并对其耦合协调度进行测算。结果表明:①2012—2019年陕西省总体的旅游效率有所上升,但多个城市的旅游效率都呈现先升后降趋势;②2012—2019年陕西省交通可达性均有了大幅提升,且区域之间的差距有所减小;③陕西省的交通可达性除西安市作为省会有较高的可达性以及对周边地区具有的辐射作用外,总体呈现南北强、东西弱的特点;④陕西省各区域旅游效率与交通可达性的耦合协调水平较高,除商洛市外其他区域都达到了中级协调及以上状态。

农村普惠金融供给协同机制与效率分析

推算政府与农村金融机构协同供给农村普惠金融的演化稳定策略,并基于30个省(自治区、直辖市)的宏观面板数据,使用SBM与超效率SBM模型测算两者之间的供给协同效率,进一步通过Tobit模型分解政府和农村金融机构各投入变量对协同效率的影响。结果表明:政府在农村普惠金融实施过程中的主导性决定了其协同决策能够考量自身的成本与收益,而农村金融机构的协同决策较大程度上受政府决策的影响;整体上,我国的农村普惠金融供给协同效率呈逐年上升趋势,其中东部和较发达的中部地区协同效率较高,而西部和欠发达的中部部分地区协同效率偏低;农村基础设施投入、金融机构网点数与协同效率分别呈倒U型和正U型关系,当前这两种要素的投入量均处于不足状态;涉农贷款补贴、金融机构从业人员数和人均农业贷款对协同效率存在正向促进作用,而金融风险对冲机制和农业保险赔付率为负向影响。

中国三大城市群数字经济与生态经济效率耦合协调的时空特征及影响因素研究

基于数字经济和生态经济效率的丰富内涵,以京津冀、长三角以及珠三角三大城市群为研究对象,综合运用熵权-TOPSIS法、Super-SBM模型以及耦合协调模型,系统分析2011-2021年数字经济与生态经济效率耦合协调度的时空演变特征,并结合面板Tobit模型探讨其影响因素。结果显示:(1)三大城市群数字经济与生态经济效率耦合协调度表现出持续增长的良好态势,协调度均值从高到低排序依次为:珠三角>长三角>京津冀,京津冀城市群以北京市为中心,充分发挥“一核”的辐射作用,长三角城市群呈现“以高值为中心,连片发展”的特点,珠三角城市群则表现出“中间高、两端低”的趋势。(2)经济发展水平、金融发展水平对三大城市群耦合协调度具有显著的正向促进作用,而对外开放程度、政府干预程度、科技水平以及产业结构水平对城市群耦合协调发展的影响具有明显的区域差异性。

2011—2021年福建省种植业绿色生产与社会综合发展的耦合协调

[目的]了解2011—2021年福建省种植业绿色生产效率与全省社会综合发展的耦合协调水平,以期促进福建省种植业绿色发展。[方法]基于2011—2021年统计数据,采用碳排放系数法计算福建省种植业碳排放强度;通过SBM模型比较全省种植业绿色生产效率,并基于耦合协调模型衡量了种植业绿色生产效率与当地社会综合发展的耦合协调水平。[结果](1)2011—2021年,福建省种植业碳排放强度总体上呈现先增后减的趋势。(2)福建省种植业绿色生产大致划分为四类,第一类是缓慢增长型,包括泉州和南平;第二类是先降后增型,包括莆田;第三类是稳定型,包括厦门;第四类是较快发展型,包括福州、龙岩、宁德、三明和漳州。(3)2011—2021年,福建省种植业绿色生产效率与社会综合发展指数之间的耦合度和耦合协调度呈递增趋势。2021年,全省达到了高度耦合和优质协调。[结论]结合福建省种植业绿色发展水平以及与社会综合发展的耦合协调情况,建议持续落实福建省农业降碳减排政策,发挥绿色优质农产品的产业优势,并进一步拓展农业的社会服务功能。