Three-dimensional stability calculation method for high and large composite slopes formed by mining stope and inner dump in adjacent open pits

The 2D limit equilibrium method is widely used for slope stability analysis.However,with the advancement of dump engineering,composite slopes often exhibit significant 3D mechanical effects.Consequently,it is of significant importance to develop an effective 3D stability calculation method for composite slopes to enhance the design and stability control of open-pit slope engineering.Using the composite slope formed by the mining stope and inner dump in Baiyinhua No.1 and No.2 open-pit coal mine as a case study,this research investigates the failure mode of composite slopes and establishes spatial shape equations for the sliding mass.By integrating the shear resistance and sliding force of each row of microstrip columns onto the bottom surface of the strip corresponding to the main sliding surface,a novel 2D equivalent physical and mechanical parameters analysis method for the strips on the main sliding surface of 3D sliding masses is proposed.Subsequently,a comprehensive 3D stability calculation method for composite slopes is developed,and the quantitative relationship between the coordinated development distance and its 3D stability coefficients is examined.The analysis reveals that the failure mode of the composite slope is characterized by cutting-bedding sliding,with the arc serving as the side interface and the weak layer as the bottom interface,while the destabilization mechanism primarily involves shear failure.The spatial form equation of the sliding mass comprises an ellipsoid and weak plane equation.The analysis revealed that when the coordinated development distance is 1500 m,the error rate between the 3D stability calculation result and the 2D stability calculation result of the composite slope is less than 8%,thereby verifying the proposed analytical method of equivalent physical and mechanical parameters and the 3D stability calculation method for composite slopes.Furthermore,the3D stability coefficient of the composite slope exhibits an exponential correlation with the coordinated development distance,with the coefficient gradually decreasing as the coordinated development distance increases.These findings provide a theoretical guideline for designing similar slope shape parameters and conducting stability analysis.

Three-dimensional coordinates test method with uncertain projectile proximity explosion position based on dynamic seven photoelectric detection screen

To objectively obtain the three-dimensional coordinates of the projectile fuze proximity explosion when projectile intersects the head of missile target, we propose a dynamic seven photoelectric detection screen test method, which is made up of six plane detection screens and a flash photoelectric dynamic detection screen. The three-dimensional coordinates calculation model of the projectile proximity explosion position based on seven plane detection screens with dynamic characteristics is established.According to the relation of the dynamic seven photoelectric detection screen planes and the time values,the analytical function of the projectile proximity explosion position parameters under non-linear motion is derived. The projectile signal filtering method based on discrete wavelet transform is explored in this work. Additionally, the projectile signal recognition algorithm using an improved particle swarm is proposed. Based on the characteristics of the time duration and the signal peak error for the projectile passing through the detection screen, the signals attribution of the same projectile passing through six detection screens are analyzed for obtaining precise time values of the same projectile passing through the detection screens. On the basis of the projectile fuze proximity explosion test, the linear motion model and the proposed non-linear motion model are used to calculate and compare the same group of projectiles proximity explosion position parameters. The comparison of test results verifies that the proposed test method and calculation model in this work accurately obtain the actual projectile proximity explosion position parameters.

Three-Dimensional Analytical Modeling of Axial-Flux Permanent Magnet Drivers

In this paper, the axial-flux permanent magnet driver is modeledand analyzed in a simple and novel way under three-dimensional cylindricalcoordinates. The inherent three-dimensional characteristics of the deviceare comprehensively considered, and the governing equations are solved bysimplifying the boundary conditions. The axial magnetization of the sectorshapedpermanent magnets is accurately described in an algebraic form bythe parameters, which makes the physical meaning more explicit than thepurely mathematical expression in general series forms. The parameters of theBessel function are determined simply and the magnetic field distribution ofpermanent magnets and the air-gap is solved. Furthermore, the field solutionsare completely analytical, which provides convenience and satisfactoryaccuracy for modeling a series of electromagnetic performance parameters,such as the axial electromagnetic force density, axial electromagnetic force,and electromagnetic torque. The correctness and accuracy of the analyticalmodels are fully verified by three-dimensional finite element simulations and a15 kW prototype and the results of calculations, simulations, and experimentsunder three methods are highly consistent. The influence of several designparameters on magnetic field distribution and performance is studied and discussed.The results indicate that the modeling method proposed in this papercan calculate the magnetic field distribution and performance accurately andrapidly, which affords an important reference for the design and optimizationof axial-flux permanent magnet drivers.

Cultural Heritage System and Coordinated Protection of Ancient Sichuan Salt Road

Ancient Sichuan Salt Road(the ancient road for the transportation of Sichuan salt) is a cultural route characterized by salt transportation culture in southwest and central-west China, along which a large number of diversifi ed and systematic cultural heritages have been left, including both tangible and intangible salt transportation cultural heritages such as ancient salt transportation road, salt shop, post house, stele inscription, ancient town, ancient bridge, guild hal, and boatmen's work songs. With the rapid economic and social development, the accelerating modernization and urbanization, and also drastic changes of traffi c environment have contributed to the endangered situation of ancient Sichuan salt road cultural heritage. In face of such problems as lack of coordinated protection mechanism, destructive development, backward protection of cultural relics, and inheritance risks of intangible heritage, cultural heritages along the ancient Sichuan salt road should be protected by establishing a protection mechanism, organizing the coordinated actions of local areas along the road, investigating and rescuing cultural heritage in time, and enhancing the cooperative research. In view of the complicate and long-term nature of protecting linear cultural heritage, successful experience of domestic and foreign cultural route heritage management can be learned, salt transportation cultural heritage protection, tourism planning and development of ancient Sichuan salt road should be considered, protection of the ancient salt road should be combined with economic, social and cultural development of regions along the road, so as to explore an effective mode for the protection, development and management of large-scale linear cultural heritages consisting of both land and water routes.

Synthesis and Crystal Structure of a Three-dimensional Mn(Ⅱ) Coordination Polymer with 3-(Pyrazin-2-yloxy)-pyridine and Azide Anion as Mixed Bridge Ligand

A three-dimensional coordination polymer [Mn2（μ1.3-N3）4（μ-PP）2]n （PP = 3-（pyrazin-2-yloxy）-pyridine） has been synthesized with 3-（pyrazin-2-yloxy）-pyridine and azide anion as mixed bridge ligand, and its crystal structure was determined by X-ray crystallography. The crystal data： triclinic system, space group P1, with a = 6.794（4）, b = 9.885（6）, c = 9.947（6） A, α = 64.170（6）, β= 84.190（8）, γ= 85.319（8）°, V = 597.7（6）A^3, Z = 1, C18H14Mn2N18O2, Mr = 624.35, Dc = 1.735 g/cm^3, F（000） = 314 and μ = 1.117 mm^-1. In the crystal, the azide anion acts as a bridge ligand and makes adjacent Mn（Ⅱ） ions connect into a two-dimensional sheet on the ab plane, then 3-（pyrazin-2-yloxy）-pyridine serves as a bidentate bridge ligand to connect neighboring sheets along

Application of Digital Technology in Road and Bridge Design

With the development and progress of science and technology,road and bridge design has experienced rapid development,from the initial manual drawing design to the popularity of Computer-Aided Design(CAD),and then to today’s digital software design era.Early designers relied on hand-drawn paper design forms which was time-consuming and error-prone.Digital support for road and bridge design not only saves the design time but the design quality has also achieved a qualitative leap.This paper engages in the application of digital technology in road and bridge design,to provide technical reference for China’s road and bridge engineering design units,to promote the popularity of Civil3D and other advanced design software in the field of engineering design and development,ultimately contributing to the sustainable development of China’s road and bridge engineering.

Discourse Analysis of the Belt and Road Initiative From the Perspective of Central Asian Countries: A Case Study of the Republic of Kazakhstan

This study employs Norman Fairclough’s Critical Discourse Analysis(CDA)three-dimensional model,using the Republic of Kazakhstan as a case study,to delve into the discourse construction of China’s Belt and Road Initiative(BRI)in Central Asian countries.Through detailed analysis of policy documents,media reports,and public discussions in Central Asian countries,this paper reveals how the BRI constructs specific social practices,discourse events,and textual meanings within these nations.The findings indicate that through this global development strategy,China has not only strengthened its economic ties with Central Asian countries but has also exerted profound influences on political,cultural,and social levels.

Three-dimensional tidal current numerical model of the Oujiang Estuary

The characteristics of three-dimensional （3-D） tidal current in the Oujiang Estuary are investigated according to in situ observations. The Oujiang Estuary has features of irregular coastline, complex topography, many islands, moveable boundary, and submerged dyke, therefore, σ 3-D numerical model oil an unstructured triangular grid has been degeloped. The σ coordinate transforination, the moveable boundary and submerged dyke treatment techniques were employed in the model so it is suitable for the tidal simulations in the Oujing Estuary with submerged dyke and moveable boundary problems. The model is evaluated with the in situ data, and the results show that the calculated water elevations at 19 stations and currents at 19 profiler stations are in good agreement with measured data both in magnitude and phase. This numerical model is applied to the 3-D tidal circulation simulations of experiments in stopping flow transport through the South Branch of the Oujiang Estuary, and the feasibility to cutoff the flow in the South Branch of the Oujiang Estuary is demonstrated by numerical simulation experiments. The developed numerical model simulated the 3-D tidal current circulations in complicated coastal and estuarine waters very well.

Using three-dimensional discrete spherical Fourier descriptors based on surface curvature voxels for pollen particle recognition

This paper presents a new method for extract three-dimensional （3D） discrete spherical Fourier descriptors based on surface curvature voxels for pollen particle recognition. In order to reduce the high amount of pollen information and noise disturbance, the geometric normalized curvature voxels with the principal curvedness are first extracted to represent the intrinsic pollen volumetric data. Then the curvature voxels are decomposed into radial and angular components with spherical harmonic transform in spherical coordinates. Finally the 3D discrete Fourier transform is applied to the decomposed curvature voxels to obtain the 3D spherical Fourier descriptors for pollen recognition. Experimental results show that the presented descriptors are invariant to different pollen particle geometric transformations, such as pose change and spatial rotation, and can obtain high recognition accuracy and speed simultaneously.

Coupling coordination and evolution of finance,economy and ecological environment:The case of Silk Road provinces

Based on the comparative analysis of the coupling mechanism between finance,economy and ecological environment,this paper uses the coupling coordination degree and grey prediction model to measure the comprehensive evaluation value and coupling coordination degree of the financial,economic and ecological environment composite system of five provinces along the Silk Road in China from 2010 to 2019,and analyzes the evolution law of the coupling and coordinated development of finance,economy and ecological environment from the perspective of system coordinated development.The results show that:(1)The development of the financial and economic systems of the provinces along the Silk Road shows a relatively continuous and stable good trend,while the development of the ecosystem shows more obvious fluctuations.(2)In general,the overall level of the comprehensive evaluation of each system in the provinces along the route has shown a trend of improvement,but the level is not high.(3)During the investigation by provinces,it is found that the coordination level of the coupling coordination degree of finance,economy and ecological environment of each province is in three stages:moderate disorder,mild disorder,and imminent imbalance.However,Shaanxi Province has changed from imminent imbalance to barely coordination earlier,which indicates that there is regional heterogeneity in the three coupling coordination relationships among regions.(4)According to the calculation of the gray GM(1,1)model,the coupling coordination degree in Shaanxi Province will maintain a good upward trend and reach a intermediate coordination stage in 2023,while the other provinces will enter the barely coordination and primary coordination stages respectively with a slightly slower growth rate.Finally,based on the research conclusions,this paper puts forward some effective policy recommendations for the coordinated development of regional finance,economy and ecological environment,such as dredging the diffusion channels of regional financial resources,guiding market funds to participate in ecological project construction,and advocating the development of circular economy.

基于多尺度和加权坐标注意力的轻量化红外道路场景检测模型

针对道路场景下红外目标遮挡、缺乏纹理细节而导致目标误检、漏检的问题,提出一种基于多尺度和加权坐标注意力的轻量化红外道路场景检测模型(MSC-YOLO)。以YOLOv7-tiny作为基线模型,首先,在MobileNetV3的不同中间特征层引入多尺度金字塔模块PSA(Pyramid Split Attention),设计一种多尺度特征提取的轻量化主干提取网络MSM-Net(Multi-Scale Mobile Network),解决固定大小卷积核造成的特征污染问题,提高对于不同尺度目标的细粒度提取能力;其次,在特征融合网络融入加权坐标注意力(WCA)机制,叠加从中间特征图垂直和水平空间方向上获取的目标位置信息,增强目标特征在不同维度上的融合能力;最后,替换定位损失函数为高效交并比(EIoU),分别计算预测框和真实框的长、宽影响因子,提高收敛速度。在Flir数据集上进行验证实验,与YOLOv7-tiny模型相比,在mAP(IoU=0.5)仅降低0.7个百分点的前提下,MSC-YOLO的参数量减少67.3%,浮点运算次数减少54.6%,模型大小减小60.5%,帧率在RTA 2080Ti上达到101,在检测性能和轻量化上达到平衡,满足红外道路场景的实时检测需求。

参数扰动对一种先前的车辆制动控制和防护方法的影响

探究了作者早先提出的一种车辆制动控制防护方法在参数扰动下的防护效果。用MADYMO虚拟仿真软件,对4种形状的典型车头开展了仿真,分析了以下参数:人体头部与车体首次接触时间、制动系统协调时间、路面附着因数:扰动时,对该制动控制防护方法的影响。结果显示:在人体头部与车体首次接触时间时为80~100 ms时,对加权伤害费用(WIC)降幅的影响最显著,但不同车型下的参数敏感性排序存在差异。在路面附着因数扰动为0.45~0.80时,人车碰撞损伤未增加;但地面所致WIC降幅均大于零,可有效降低人地碰撞损伤。在制动系统协调时间参数扰动区间为80~350 ms时,该车辆制动控制防护方法仍然保持有效。

丝绸之路经济带旅游产业-经济-环境系统空间错位分析

丝绸之路经济带是中国形成全方位对外开放格局、实现东西部均衡协调发展的关键,旅游业的高质量发展是丝绸之路经济带建设主要组成部分。论文通过构建旅游产业—经济—环境系统评价体系,基于面板数据,利用重力模型、空间错位指数模型、均方差分解等方法,测度2010—2019年丝绸之路经济带九省份旅游产业、经济、环境系统的空间错位状况及影响因素。研究发现:三大系统重心均向西南四省份偏移且各自间存在错位现象,其中经济重心错位最为显著;总体空间错位指数呈上升趋势,整体错位状况加深,总体差异主要来源于西北与西南地区的区间差异;冷热点时空演变呈现“西南集中、西北分散”的特征;各地区的空间错位指数受多系统多因素的影响且多指向生态环境和经济系统。

基于博弈论的蒙古国经济社会-生态环境耦合协调度驱动因素及其特征研究

蒙古国生态环境持续恶化及中蒙边境生态屏障薄弱是2国面临的共同发展问题,但目前全国尺度下综合性、多要素的经济社会与生态环境耦合协调发展类型、特征及驱动因素等尚缺乏定量评估,影响了中蒙双方共建“一带一路”绿色发展格局的统筹推进.本文总结了蒙古国经济社会及生态环境发展现状,采用AHP-CRITIC-博弈论法计算指标要素主客观组合权重,综合评价了蒙古国经济社会-生态环境发展的耦合协调度.结果表明,2005−2021年蒙古国经济社会-生态环境耦合协调度呈现波动上升趋势,耦合协调度类型始终属于严重失调类型,生态环境发展滞后是目前发展阶段的特征.社会发展水平和生态环境禀赋是经济社会子系统和生态环境子系统的主要驱动因素.皮尔逊相关性分析表明,水域面积和森林资源减少、水质恶化以及沙尘天气等灾害/事故响应增加与经济社会稳步发展的不匹配可能是导致该特征形成且耦合协调度始终较低的原因.为推动双边绿色发展战略深化对接,中蒙2国应在促进经济社会发展交流的同时,深化加强生态环境保护修复力度以恢复生态环境禀赋的交流合作.

改进YOLOv8的道路缺陷检测算法

道路在长期使用后路面会出现各种缺陷,未能及时侦测和修补这些缺陷可能严重缩短道路寿命并危害行车安全。因此,道路缺陷的即时检测是一项重要的任务。传统的检测方法存在检测速度慢,成本要求高的问题。为了解决这些问题,在YOLOv8的基础上提出了一种名为DML-YOLO新型道路检测算法,该算法在主干网络中加入MPCA(MultiPath coordinate attention)注意力机制,提高主干网络的特征提取能力,在此基础上提出了C2f-MPDC模块,动态调整感受野,提高检测能力;重新设计了网络的颈部结构,提出新的特征融合金字塔结构DFPN(diver-sity feature pyramid network),减小模型的体积并融合低层的特征图获得丰富的细节信息,提高检测小目标的成功率;设计一种轻量级共享卷积检测头(LSCD head),减少模型尺寸,提高检测效率。大量实验结果表明,DML-YOLO在RDD2022数据集和VOC2007数据集上平均检测精度mAP@0.5分别为89.6%和73.6%,优于其他测试模型,并且参数量和计算量相较于YOLOv8模型分别减少了32.37%和14.49%,更加适合部署在嵌入式系统、移动设备等计算资源受限和边缘计算的场景。

智能化转型背景下自动驾驶产业化的中国实践

自动驾驶是当今交通社会转型的一种变革性力量。作为人工智能技术集中应用的典型场景,自动驾驶具备技术和社会“双重”属性,其产业化过程本质上是技术因素和社会因素相互建构的过程。基于175家智能网联汽车企业的关系数据和819份自动驾驶实地社会实验的问卷数据,对中国自动驾驶产业化实践方案的形成机制与理论逻辑进行系统分析。研究表明:自动驾驶在高环境嵌入性作用下,一方面嵌入中国复杂道路环境,另一方面嵌入中国独特社会环境,导致以单车智能为核心的技术路线难以为继,最终在一系列互补性技术创新和多元创新主体协同创新作用下,以车路协同为核心的智能网联汽车发展道路成为中国自动驾驶产业化的实践选择。

车联网中最小化峰值信息年龄的任务卸载策略

为解决车联网中数据密集型任务对信息新鲜程度极为敏感的问题,针对车路协同场景提出一种最小化峰值信息年龄策略。在所提策略中,将峰值信息年龄定义为任务更新间隔、传输时间以及等待时间三者之和的期望,将变量高度耦合的非线性优化问题转化为任务卸载比例和任务更新间隔两个子问题。在任务卸载比例问题中,证明最小峰值信息年龄的存在条件并获得最优卸载比例。通过内点罚函数法求解车辆任务更新间隔问题。给出两个子问题的交替迭代策略,实现全局车辆峰值信息年龄最小。数值仿真结果验证了所提策略在减少全局车辆峰值信息年龄方面的有效性。

基于浮动车轨迹数据的干线信号协调配时优化

为了提高城市干线的通行效率,缩短车辆在干线行驶时的平均延误,基于浮动车轨迹数据提出一种城市干线交通信号协调控制优化方法。该方法根据浮动车采集的时空轨迹数据,使用最大期望算法对混合车流(浮动车和其他车辆)到达率进行预测。结合信号状态,通过计算干线道路上、下行双向饱和度,以总延误最短为优化目标建立了干线协调配时优化算法,并采用遗传算法进行求解。以合肥市黄山路路段为例,比较无协调控制、传统定时协调控制和基于轨迹数据的信号协调控制。结果表明,所提供的方案可有效缩短干线交叉口车辆总延误,减少燃油消耗。

基于车路协同的智能网联小车车速控制系统设计

车路协同作为当前中国自动驾驶的主要发展路径,通过不断融合“聪明的车”和“智能的路”两大核心要素,实现了车与路的高效协同,具有覆盖面广,产业链长,跨界融合特征突出的特点。同时,随着智能网联汽车朝着智慧出行的加速推进,渗透率逐渐增长,使得交通效率日益提高的同时大大降低了交通事故的发生率,改变了人们的生活方式。基于此,本文设计了一种基于车路协同的智能网联小车车速控制策略,通过实现智能网联小车车速与路侧单元红绿灯周期信号的数据共享,达到智能网联小车对红绿灯信号的判断并作出相应速度控制的目标。

“一带一路”视域下西部陆海新通道的产业协同发展与布局优化研究

西部陆海新通道是一条地处我国西部腹地,连接“一带一路”,服务全球发展的新战略通道。它以贯通南北的要道形式将“一带”和“一路”在我国西部连接起来。建设西部陆海新通道基础在产业,思路在协同。本文分析西部陆海新通道的产业基础条件与产业结构情况,选择区位熵作为衡量指标,研究行业门类的行业专业化特征,梳理推进产业协同发展需要解决的问题,提出基于新通道产业发展条件加快推进产业协同,为进一步推进共建“一带一路”走深走实提供坚实支撑,服务新通道建设发展和产业布局优化的思路建议。