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模型试验 6

DX桩 4

承载力 2

有限元分析 2

1860 MPa等级 1

360°表征 1

4250 m 1

ANSYS 1

BP神经网络 1

CFRP索斜拉桥 1

CP）；符号间干扰（inter symbol interference， ISI）；载波间干扰（inter carrier interference 1

GA-BP网络 1

ICI）；最大似然估计（maximum likelihood estimation 1

ISO 9705 1

ISO标准火灾实验系统 1

IgG抗体 1

LED灯具；加速老化测试；中位寿命；滑动平均误差 1

MLE） 1

OFDM）；快速傅立叶变换（Fast Fourier transform， FFT）；循环前缀（cyclic prefix 1

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基于正交实验的BP神经网络预测研究

蔡安辉,刘永刚,孙国雄

《中国工程科学》 2003年第5卷第7期页码 67-71

摘要：

用不同的L₉（3⁴）正交实验方案结果作为训练学习样本集，对BP神经网络预测应用过程的策略进行了探讨，结果表明：完备的正交实验样本集是基本训练学习单元，在完备的正交实验样本集上添加或减少样本数量，所预测的结果是不可靠的；在同一类型、同一实验的条件下，完备的信息量大的正交实验样本集，能以很高的精度预测完备的信息量小的正交实验样本集；提出了一条新的实验设计思路——通过实验得出一个完备的正交实验样本集，通过计算机用BP神经网络就可以把与已知样本集有相同影响因素和水平的所有样本的值以相当高的精度预测出来，从而大大节省时间和劳力。

关键词： BP神经网络正交实验策略实验设计思路样本集

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Development and road performance of clear asphalt with high transparency and adhesion

《结构与土木工程前沿（英文）》 2023年第17卷第2期页码 238-255 doi: 10.1007/s11709-022-0898-x

摘要： Clear asphalt (CA) currently used in light-colored asphalt mixtures (LCAM) exhibits poor transparency and adhesion. Therefore, a highly transparent CA (HCA) modified using a silane coupling agent (KH550) was prepared. Furthermore, LCAM was prepared by mixing CA and limestone aggregates. The properties of the HCA and ordinary CA (OCA) were characterized using conventional asphalt tests, optical tests, pull-off tests, ultraviolet aging tests, dynamic shear rheometry, Fourier-transform infrared spectroscopy, differential scanning calorimetry, and scanning electron microscopy. Whereas Marshall, moisture resistance, wheel tracking, trabecular bending, and British pendulum tests were employed for the LCAM. The transmittance and spectral reflectance of the HCA were 123.30 and 3.74 times greater than those of the OCA, respectively. The complex modulus and viscosity-aging index of the HCA were 48% and 53% less than those of the OCA, respectively. After modification with KH550, the Marshall stability ratio, tensile strength ratio, and flexural strain of the HCA-prepared LCAM increased by 12.92%, 25.06%, and 23.90%, respectively. However, the rutting resistance of the HCA-prepared LCAM was 14.3% less than that of the OCA-prepared LCAM. The comprehensive performances of the HCA and HCA-prepared LCAM were 49.2% and 10.3% greater than those of the OCA and OCA-prepared LCAM, respectively, indicating a high application value in the future.

关键词： light-colored asphalt pavement orthogonal test road performance spectral reflectance silane-coupling agent

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Improved analytical model for residual stress prediction in orthogonal cutting

null

《机械工程前沿（英文）》 2014年第9卷第3期页码 249-256 doi: 10.1007/s11465-014-0310-1

摘要：

The analytical model of residual stress in orthogonal cutting proposed by Jiann is an important tool for residual stress prediction in orthogonal cutting. In application of the model, a problem of low precision of the surface residual stress prediction is found. By theoretical analysis, several shortages of Jiann’s model are picked out, including: inappropriate boundary conditions, unreasonable calculation method of thermal stress, ignorance of stress constraint and cyclic loading algorithm. These shortages may directly lead to the low precision of the surface residual stress prediction. To eliminate these shortages and make the prediction more accurate, an improved model is proposed. In this model, a new contact boundary condition between tool and workpiece is used to make it in accord with the real cutting process; an improved calculation method of thermal stress is adopted; a stress constraint is added according to the volume-constancy of plastic deformation; and the accumulative effect of the stresses during cyclic loading is considered. At last, an experiment for measuring residual stress in cutting AISI 1045 steel is conducted. Also, Jiann’s model and the improved model are simulated under the same conditions with cutting experiment. The comparisons show that the surface residual stresses predicted by the improved model is closer to the experimental results than the results predicted by Jiann’s model.

关键词： residual stress analytical model orthogonal cutting cutting force cutting temperature

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Machinability of damage-tolerant titanium alloy in orthogonal turn-milling

Tao SUN, Lufang QIN, Junming HOU, Yucan FU

《机械工程前沿（英文）》 2020年第15卷第3期页码 504-515 doi: 10.1007/s11465-020-0586-2

摘要： The damage-tolerant titanium alloy TC21 is used extensively in important parts of advanced aircraft because of its high strength and durability. However, cutting TC21 entails problems, such as high cutting temperature, high tool tip stress, rapid tool wear, and difficulty guaranteeing processing quality. Orthogonal turn-milling can be used to solve these problems. In this study, the machinability of TC21 in orthogonal turn-milling is investigated experimentally to optimize the cutting parameters of orthogonal turn-milling and improve the machining efficiency, tool life, and machining quality of TC21. The mechanism of the effect of turn-milling parameters on tool life is discussed, the relationship between each parameter and tool life is analyzed, and the failure process of a TiAlN-coated tool in turn-milling is explored. Experiments are conducted on the integrity of the machined surface (surface roughness, metallographic structure, and work hardening) by turn-milling, and how the parameters influence such integrity is analyzed. Then, reasonable cutting parameters for TC21 in orthogonal turn-milling are recommended. This study provides strong guidance for exploring the machinability of difficult-to-cut-materials in orthogonal turn-milling and improves the applicability of orthogonal turn-milling for such materials.

关键词： orthogonal turn-milling damage-tolerant titanium alloy tool life and failure machined surface integrity machinability

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Singularity loci of an orthogonal spherical two-degree-of-freedom parallel mechanism

Jialun YANG, Feng GAO,

《机械工程前沿（英文）》 2009年第4卷第4期页码 379-385 doi: 10.1007/s11465-009-0075-0

摘要： Singularity analysis plays an important role in the design of robots, especially for parallel robots. In this paper, the direct and inverse kinematics of an orthogonal spherical two-degree-of-freedom parallel mechanism is proposed based on the modified Euler angles. All the singular poses of the mechanism are achieved through the direct kinematic analysis. Self-motions, which are different from the general spherical 5 parallel mechanisms, are also discussed. Singularity loci in the joint space and Cartesian space are plotted according to the Jacobin of the mechanism. Result shows that the singularity loci at the joint space are two circles and one line, whereas at the Cartesian space are a circle.

关键词： 2-DOF orthogonal spherical parallel mechanism singularity loci self-motions

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Variable eccentric distance-based tool path generation for orthogonal turn-milling

Fangyu PENG,Wei WANG,Rong YAN,Xianyin DUAN,Bin LI

《机械工程前沿（英文）》 2015年第10卷第4期页码 352-366 doi: 10.1007/s11465-015-0361-y

摘要：

This study proposes an algorithm for maximizing strip width in orthogonal turn-milling based on variable eccentric distance. The machining error model is first established based on the local cutting profile at the contact line. The influencing factors of the strip width are then investigated to analyze their features and determine an optimizing strategy. The optimized model for maximum machining strip width is formulated by adopting a variable eccentric distance. Hausdorff distance and Fréchet distance are introduced in this study to implement the constraint function of the machining error in the optimized model. The computing procedure is subsequently provided. Simulations and experiments have been conducted to verify the effectiveness of the proposed algorithm.

关键词： orthogonal turn-milling variable eccentric distance local cutting profile machining strip-width maximization

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基于GA－BP网络的人工湿地污水净化效果研究

黄娟,王世和,雒维国,钱卫一,鄢璐

《中国工程科学》 2007年第9卷第2期页码 79-83

摘要：

人工湿地作为污水处理领域的一种新型生态技术，逐渐得到应用并倍受关注。人工湿地污水净化过程呈多参数影响的复杂非线性状态，采用传统的数学方法难以建立准确的数学模型并进行多因素分析，也无法精确定出湿地系统最佳运行工况。基于大量可靠的试验数据，首次采用遗传神经网络方法模拟湿地除污系统，详细论述了网络拓扑结构优化和训练数据预处理等关键问题，建立了可靠的GA－BP模型，并采用该模型仿真湿地系统正交试验，依据正交试验结果对影响因素进行分级，确定了最佳运行工况，并在此基础上有针对性地提出可行的强化除污措施。

关键词：人工湿地污水净化 GA-BP网络正交试验

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基于双正交复序列的高效扩频调制方法

史小红

《中国工程科学》 2012年第14卷第3期页码 108-112

摘要：

提出了一种采用双正交复序列的高效扩频调制与解调方法（DoCS）。输入数据比特流被分割为长度为M的组，每组的M比特作为输入码字，从2M-2个长度为L的DoCS序列中选择一条序列进行发送，被选中的序列以QPSK方式调制在载波上，实现扩频通信。文中还提出了一种前向相位校正(FPC)方法来解决该系统中收发两端的载波同步问题。

关键词：调制与解调技术高效扩频调制前向相位校正双正交码

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基于虚拟样机技术的汽车操纵稳定性参数正交优化设计

车华军,陈南,殷国栋

《中国工程科学》 2009年第11卷第9期页码 81-86

摘要：

以某型轿车底盘为研究对象，采用虚拟样机软件ADAMS建立整车多体动力学仿真模型；结合汽车操纵稳定性的客观定量评价标准，建立了直接生成操纵稳定性评价值的ADAMS函数；用ADAMS软件结合正交试验方法对整车操纵稳定性进行了虚拟正交优化设计。虚拟样机技术在车辆操纵稳定性参数正交优化中的应用，不仅使仿真模型与集中质量模型相比提高了精度，还分析出整车操纵稳定性的主要零部件影响因素，得到了最优的一组设计方案。由于是直接对具体零部件的优化，整个设计过程适于在企业中应用。

关键词：虚拟样机汽车操纵稳定性正交优化设计

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煤层注水参数的数量化理论正交设计优化法的研究

秦书玉,秦伟瀚

《中国工程科学》 2003年第5卷第10期页码 52-55

摘要：

应用正交设计优化煤层注水工艺参数的组合，对地质条件稳定的煤层是实现最佳注水效果的一种较好的方法。但是，对于地质条件不断变化的煤层，采用该方法，其效果不一定能满足注水工程要求。为此，针对地质因素为不稳定状态下的煤层及影响煤层注水的地质因素既有定性变量又有定量变量的特征，提出利用数量化理论与正交设计2种方法确定注水工艺参数的最优组合，并进行了工程试验优化研究。试验结果表明，此法节省注水试验工程量，接近实际工程要求。

关键词：数量化理论工艺参数正交设计煤层注水试验研究

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Mechanical performance analysis and stiffness test of a new type of suspension bridge

《结构与土木工程前沿（英文）》 2021年第15卷第5期页码 1160-1180 doi: 10.1007/s11709-021-0760-6

摘要： A new type of suspension bridge is proposed based on the gravity stiffness principle. Compared with a conventional suspension bridge, the proposed bridge adds rigid webs and cross braces. The rigid webs connect the main cable and main girder to form a truss that can improve the bending stiffness of the bridge. The cross braces connect the main cables to form a closed space truss structure that can improve the torsional stiffness of the bridge. The rigid webs and cross braces are installed after the construction of a conventional suspension bridge is completed to resist different loads with different structural forms. A new type of railway suspension bridge with a span of 340 m and a highway suspension bridge with a span of 1020 m were designed and analysed using the finite element method. The stress, deflection of the girders, unbalanced forces of the main towers, and natural frequencies were compared with those of conventional suspension bridges. A stiffness test was carried out on the new type of suspension bridge with a small span, and the results were compared with those for a conventional bridge. The results showed that the new suspension bridge had a better performance than the conventional suspension bridge.

关键词： new type of suspension bridge stiffness test mechanical performance railway bridge space truss

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Mixed mode properties of CNT reinforced composites using Arcan test rig

Jacob MUTHU

《结构与土木工程前沿（英文）》 2015年第9卷第4期页码 397-404 doi: 10.1007/s11709-015-0321-y

摘要： Composite materials reinforced with carbon nanotubes were mechanical tested using Arcan test rig under Mode-I, Mode-II and mixed mode loading conditions to obtain their fracture properties. The butterfly composite specimens were fabricated with 0.02, 0.05 and 0.1 wt % CNTs. The polyester/CNT composite was fabricated using VRTM (Vacuum Resin Transfer Molding) where the CNTs were first functionalised to reach an optimum properties. Arcan test rig was designed and fabricated to work with the Shimadzu testing machine. The results show that the functionalised CNTs have improved the fracture behavior by acting as bridge between the cracked face. In addition, the fracture properties were not improved for the higher weight fraction of 0.1 wt% CNTs.

关键词： CNT composites Arcan test rig stress intensity factor

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Accelerated life-time test of MEA durability under vehicle operating conditions in PEM fuel cell

Tian TIAN, Jianjun TANG, Wei GUO, Mu PAN

《能源前沿（英文）》 2017年第11卷第3期页码 326-333 doi: 10.1007/s11708-017-0489-z

摘要： In this paper, a novel accelerated test method was proposed to analyze the durability of MEA, considering the actual operation of the fuel cell vehicle. The proposed method includes 7 working conditions: open circuit voltage (OCV), idling, rated output, overload, idling-rated cycle, idling-overload cycle, and OCV-idling cycle. The experimental results indicate that the proposed method can effectively destroy the MEA in a short time (165 h). Moreover, the degradation mechanism of MEA was analyzed by measuring the polarization curve, CV, SEM and TEM. This paper may provide a new research direction for improving the durability of fuel cell.

关键词： polymer electrolyte membrane fuel cell accelerated life-time test load cycling test durability

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XB高精度火箭橇试验滑轨

杨兴邦

《中国工程科学》 2000年第2卷第10期页码 98-104

摘要：

火箭橇试验滑轨是一种大型地面动态模拟试验设备，用于研究试验件在空中高速度、高加速度运行时所遇到的诸多技术问题，其技术核心是一百万分之一的轨道直线性相对精度。它要求具有稳定的滑轨基础、高直线度准直基准线和光滑平顺的钢轨作为基本条件，需要采用钢轨精密机械加工、钢轨焊接、焊缝超声波探伤、轨道张拉锚固锁定、轨道直线度调整等新工艺技术。我国已成功地建成世界上唯一的、钢轨经精密机械加工后再全程焊接的XB高精度火箭橇试验滑轨。文章论述了它的诞生背景、设计思路、技术方案、技术与建造特点以及应用展望，该滑轨直线度达到世界先进水平。

关键词：火箭滑橇试验滑轨地面动态模拟试验

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New computational treatment of optical wave propagation in lossywaveguides

Jian-xin ZHU,Guan-jie WANG

《信息与电子工程前沿（英文）》 2015年第16卷第8期页码 646-653 doi: 10.1631/FITEE.1400406

摘要： In this paper, the optical wave propagation in lossy waveguides is described by the Helmholtz equation with the complex refractive-index, and the Chebyshev pseudospectral method is used to discretize the transverse operator of the equation. Meanwhile, an operator marching method, a one-way re-formulation based on the Dirichletto-Neumann (DtN) map, is improved to solve the equation. Numerical examples show that our treatment is more efficient.

关键词： Adjoint operator Orthogonal Chebyshev Pseudospectral method Dirichlet-to-Neumann map