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 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.

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

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.

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.

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.

基于语义分割的乡村道路识别

针对目前智能农机在乡村复杂环境下行驶时对周围特征识别精度不足的问题,以乡村道路场景为研究对象,提出一种改进PP-LiteSeg模型。首先使用STDC对图像特征进行提取,在保证轻量化的同时确保特征信息完整;然后将条形池化引入简单金字塔模块,加强特征的提取能力,并将坐标注意力加入统一注意力融合模块,进一步加强多尺度特征的融合,捕获更为丰富的信息,从而提高模型对乡村复杂场景识别的准确率。实验结果表明,在不同场景下,所提模型可以达到较好的分割效果,建筑物、柏油路、障碍等单个类别的准确率均达到80%以上,能够有效地分割乡村道路场景。改进模型可为智能农机在乡村道路场景下的安全行驶提供技术参考。

“一带一路”倡议下实用新型制度的国际协调

“一带一路”倡议提出以来已逾十载,我国在这一过程中逐渐具备了规则创新的能力与契机,该种创新可由缺乏国际协调的实用新型制度先行。“一带一路”共建国家以及沿线区域性知识产权组织存在实用新型制度本土化的立法基础、改革经验及协调实践,考虑实用新型制度在保护渐进式创新、维护共建发展中国家利益、提升知识产权国际博弈话语权等方面所发挥的作用,我国应当推行从软法到硬法的实用新型国际协调行动。包括但非限于借助“一带一路”国际合作高峰论坛发起协调倡议、倡导由世界知识产权组织出台《实用新型示范法》、借鉴欧盟的开放协调机制进行规则协商等,并将实用新型制度引入更多双边、多边贸易协定谈判场景。

新亚欧陆海联运通道建设中跨区域协同发展对策研究

新亚欧陆海联运通道建设是推动区域经济一体化发展的重要战略,跨区域协同发展则是通道建设的方向和保障。近年来,通道建设取得了显著进展,但跨区域协同发展水平仍有较大提升空间,并亟待寻求解决方案,以促进江苏沿海地区独特区位优势更好地转化为开放发展优势,更好服务于我国新发展格局构建。在对现有文献进行综述基础上,本文对新亚欧陆海联运通道建设中跨区域合作现状及问题进行了分析。结果表明,新亚欧陆海联运通道建设中面临的主要问题是支撑不牢、流通不畅、能级不高和保障不足,需进一步健全基础设施、优化配套服务,优化运输物流、提升物流效率,构建全方位协同开放体系、推动区域经济一体化,加强政策支撑、完善统筹协调机制,以促进跨区域协同发展,进而推动新亚欧陆海联运通道建设。

A three-dimensional k-ε-k_p model in curvilinear coordinates for sediment movement and bed evolution

To aim at the substitution of the magnitude and direction of water flow movement near bed for those of bed load transport in solid-liquid two-phase one-fluid model, and to simulate the effect of secondary flow on transverse bed load transport in channel bends and the effect of bed slope on bed load trans- port in a better way, a three-dimensional k-ε-kp solid-liquid two-phase two-fluid model in curvilinear coordinates is solved numerically with a finite-volume method on an adaptive grid for studying wa- ter-sediment movements and bed evolution in a 120° channel bend. Numerical results show that the trajectories of solid-phase deviate from those of liquid-phase in the channel bend, and the deviation increases with the increase of the particle diameters. The calculated bed deformation by the k-ε-kp model is in better agreement with measured bed deformation than those by one-fluid model. It is proved that the k-ε-kp model can simulate the effect of secondary flow on lateral bed load transport with the higher accuracy than the one-fluid model.

A Novel 3-D Zn(Ⅱ) Coordination Polymer for Inhibiting the Human Osteosarcoma Cells Growth

A new three-dimensional Zn（II） coordination polymer, namely [Zn4（bpydb）3（tz）2（H2O）2]n（1）, has been synthesized by the self-assembly reactions of Zn（NO3）2·6H2O, bpydb H2, Htz and DMF. Single-crystal X-ray structural analysis reveals that compound 1 features a three-dimensional framework structure and is the first example of Zn-containing coordination polymers based on two kinds of ligands bpydb H2 and Htz. It crystallizes in triclinic, space group P1 with a = 14.9953（12）, b = 17.5335（17）, c = 20.2381（11）A, α = 115.225（7）, β = 92.329（5）, γ = 105.606（8）o, V = 4561.9（7） A^3, Z = 2, F（000） = 1644, Dc = 1.177 Mg/m^3, Mr = 1616.76 and μ = 1.098 mm^-1. The antitumor activities of compound 1 and its corresponding organic ligands（bpydb H2 and Htz） were investigated for inhibiting human osteosarcoma cells（MG-63 and U-2 OS） growth by MTT assay. It was found that compared with the two ligands, compound 1 exerted rather potent activities against all of these cell lines.

Hydrothermal Synthesis, Crystal Structure and Fluorescence Property of a Novel Coordination Polymer [Eu_2(C_6H_8O_4)_3(H_2O)_2]_n·n(4,4′-bpy)

A novel coordination polymer [Eu2(C6H8O4)3(H2O)2]n?n(4,4?-bpy) (Mr = 928.51) was synthesized by the hydrothermal reaction of EuCl3?6H2O, adipic acid and 4,4?-bpy, and determined by elemental analysis, IR spectroscopy, thermal gravimetric analysis, single-crystal diffraction and fluorescence property. X-ray analysis reveals that a three-dimensional network has been formed between Eu3+ by carboxyl of adipic acid. The crystal is of orthorhombic, space group Pbcn with a = 21.870(7), b = 7.652(2), c = 19.624(6) ?, V = 3284.1(17) ?3, Z = 4, Dc = 1.878 g/cm3, μ = 3.854 mm-1, F(000) = 1824, R = 0.0345 and wR = 0.0565. The coordination polymer exhibits intensive red light under UV excitation at room temperature, which is attributed to the 5D0→7F2 transition of Eu(Ⅲ) ions.

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.

Analysis on the Demand and Countermeasures of Air Ground Coordination in China’s Aviation Medical Rescue

Compared with ground first aid, aviation medical rescue has better advantages in mountain disaster relief, remote transfer and rapid medical rescue response, which is an effective supplement to ground medical first aid. China’s aviation medical rescue is in its infancy, compared with the level of developed countries there is a big gap. Based on the development and characteristics of aviation medical rescue in China, this paper combs the process of air-ground cooperative rescue, analyzes the demand and current situation of air-ground cooperative rescue in aviation medical rescue in China, and puts forward some countermeasures to improve the ability of aviation medical rescue in China.

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。

路轨协同下地铁配送网络抗毁性分析与关键节点识别

为研究路轨(道路-轨道)协同城市配送中地铁网络的抗毁性和关键节点,支撑路轨协同下城市配送的组网模式以及配送网络的可靠性提升,首先,以相对网络效率、相对负载熵为抗毁性测度指标,基于改进的耦合映像格子(CML)模型,研究不同攻击模式下的网络抗毁性变化;其次,选取反映网络运输效率的中心性指标和反映网络承载能力的现实性指标,构建网络关键节点综合识别模型;然后,通过分析不同指标权重下的网络抗毁性水平,得到最优权重取值下的关键节点集合;最后,以成都市地铁网络为例进行实证分析,验证该模型的有效性和实用性。研究结果表明:在同等扰动强度下,地铁网络面对随机攻击时抗毁能力更强;当面临外部扰动时,相对网络效率与相对负载熵损失在20%以上的节点占比分别为6.3%与6.8%,其中相对网络效率损失最大可达56.3%,相对负载熵损失最大可达50.2%;同时,考虑现实性指标与中心性指标,平均每个关键节点造成的相对网络效率损失与相对负载熵最大损失分别为8.99%与4.38%,需予以重点关注。

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。