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严格雪崩准则 3

Bent函数 2

Walsh循环谱 2

功能 2

动力学 2

多输入多输出 2

振动信号 2

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自相关函数 2

遗传算法 2

2-基展开 1

3S 1

AR模型 1

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BP算法 1

B样条函数 1

CAESAR竞赛；认证加密算法；分组密码；序列密码；哈希函数；安全性评估 1

CDMA 1

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

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Calculation of collision frequency function for aerosol particles in free molecule regime in presence

Xiaowei LUO, Yannick BENICHOU, Suyuan YU

《能源前沿（英文）》 2013年第7卷第4期页码 506-510 doi: 10.1007/s11708-013-0275-5

摘要： The collision frequency function for aerosol particles has already been calculated for the free molecule regime and for the continuum range. The present work, taking into account the influence of internal force fields such as magnetic force, electric force and molecular forces, created by particles themselves, recalculated the collision frequency in the case of particles much smaller than the mean free path of the gas (free molecule regime). Attractive forces increase naturally the collision frequency, while repulsive forces decrease it. The calculation was performed for all types of central forces deriving from a potential, including Coulomb forces and Van der Waals forces.

关键词： aerosol particles collision frequency function coagulation

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基于钻头运动诱发套管头振动信号检测的井眼防碰监测方法

何保生,刘刚,王平双,文敏

《中国工程科学》 2011年第13卷第5期页码 74-78

摘要：

针对海上加密调整井的井眼防碰问题，设计了一种井筒防碰地面监测预警系统，并进行了现场应用。系统利用加速度传感器监测通过套管传输到套管头上的钻头振动信号，利用数据采集、信号滤波放大和专门编制的监测软件记录分析传感器采集的振动信号，通过对信号的时域、频域分析，确定信号特征与井间相对距离的关系，识别钻头对风险井套管的趋近或碰撞。应用结果表明，该系统能有效感知通过地层、套管传输到套管头的钻头振动信号，并能识别出钻头对风险邻井的趋近，验证了系统在设计理论和方法上的可行性，为加密调整井的井眼防碰、保证钻井安全提供了一种有效的手段。

关键词：调整井防碰风险井振动信号时域分析频域分析

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An efficient stochastic dynamic analysis of soil media using radial basis function artificial neural

P. ZAKIAN

《结构与土木工程前沿（英文）》 2017年第11卷第4期页码 470-479 doi: 10.1007/s11709-017-0440-8

摘要： Since a lot of engineering problems are along with uncertain parameters, stochastic methods are of great importance for incorporating random nature of a system property or random nature of a system input. In this study, the stochastic dynamic analysis of soil mass is performed by finite element method in the frequency domain. Two methods are used for stochastic analysis of soil media which are spectral decomposition and Monte Carlo methods. Shear modulus of soil is considered as a random field and the seismic excitation is also imposed as a random process. In this research, artificial neural network is proposed and added to Monte Carlo method for sake of reducing computational effort of the random analysis. Then, the effects of the proposed artificial neural network are illustrated on decreasing computational time of Monte Carlo simulations in comparison with standard Monte Carlo and spectral decomposition methods. Numerical verifications are provided to indicate capabilities, accuracy and efficiency of the proposed strategy compared to the other techniques.

关键词： stochastic analysis random seismic excitation finite element method artificial neural network frequency domain analysis Monte Carlo simulation

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深水钻井隔水导管挠曲方程和固有频率的计算及其研究

姜伟

《中国工程科学》 2011年第13卷第5期页码 66-73

摘要：

从深水钻井应用的隔水导管的使用实际情况出发，应用弹塑性力学中的位移复分原理的Ritz法，考虑了隔水导管所受到的轴向张力T和隔水导管受力产生的倾角α以及由于自重q所产生的自重横向分力qsin α和轴向分力qcos α，建立了较为合理的挠曲方程，并且由此得到隔水导管的固有振动频率的简易计算求解方法。由于该挠曲方程结合了钻具的实际情况，其挠曲方程的约束条件采用的是一端铰支、一端自由的形式，因此其研究更接近实际情况，研究旨在为深水钻井隔水导管的合理使用设计和选择，提供一种更快捷实用的方法，对深水钻井作业有一定的指导意义。

关键词：深水钻井隔水导管挠曲方程固有频率形状函数

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泰州大桥中塔墩防船撞研究

沈刚,伏耀华,金允龙

《中国工程科学》 2010年第12卷第4期页码 73-77

摘要：

泰州大桥主墩位于航道边缘，可能遭受船舶的撞击。为保护大桥，综合考虑多种因素研究大桥中塔墩防船撞方案。针对泰州大桥三塔悬索桥型，结合通航船舶规划、桥梁参数、桥墩基础特点，开展防撞研究，提出针对性防撞方案，进行防撞特性计算分析，确定防撞方案的技术、经济特性。通过有限元数值仿真技术，研究泰州大桥在船舶撞击下的安全性和防撞方案的有效性。

关键词：船桥碰撞船撞力船舶碰撞数值仿真独立防撞墩钢套箱防撞风险分析

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航海避碰智能系统

郝燕玲,刘宇宏,孙枫,孙尧

《中国工程科学》 2000年第2卷第3期页码 48-53

摘要：

文章设计了一种智能型航海避碰系统，即航海智能避碰专家系统。该系统具有多元分层知识库体系结构，采用框架、产生式规则、过程及神经网络等多种知识表示形式，实现了航海避碰知识的表示、存储。建立了基于演绎推理、类比推理、换位推理、神经网络复合推理及元级推理的多路推理机制，克服单一推理的不足。分别建立了碰撞危险度、避让时机及会遇态势分类g型。提出基于层次分析法的多船会遇避让方案选取策略，建立了最优化数学模型。仿真试验表明：系统能对各种避碰情况给出正确的避让方案。

关键词：避碰专家系统神经网络模糊技术多目标优化

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Inverse identification of the mechanical parameters of a pipeline hoop and analysis of the effect of preload

Ye GAO, Wei SUN

《机械工程前沿（英文）》 2019年第14卷第3期页码 358-368 doi: 10.1007/s11465-019-0539-9

摘要： To create a dynamic model of a pipeline system effectively and analyze its vibration characteristics, the mechanical characteristic parameters of the pipeline hoop, such as support stiffness and damping under dynamic load, must be obtained. In this study, an inverse method was developed by utilizing measured vibration data to identify the support stiffness and damping of a hoop. The procedure of identifying such parameters was described based on the measured natural frequencies and amplitudes of the frequency response functions (FRFs) of a pipeline system supported by two hoops. A dynamic model of the pipe-hoop system was built with the finite element method, and the formulas for solving the FRF of the pipeline system were provided. On the premise of selecting initial values reasonably, an inverse identification algorithm based on sensitivity analysis was proposed. A case study was performed, and the mechanical parameters of the hoop were identified using the proposed method. After introducing the identified values into the analysis model, the reliability of the identification results was validated by comparing the predicted and measured FRFs of the pipeline. Then, the developed method was used to identify the support stiffness and damping of the pipeline hoop under different preloads of the bolts. The influence of preload was also discussed. Results indicated that the support stiffness and damping of the hoop exhibited frequency-dependent characteristics. When the preloads of the bolts increased, the support stiffness increased, whereas the support damping decreased.

关键词： inverse identification pipeline hoop frequency response function mechanical parameters preload

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Identification of dynamic stiffness matrix of bearing joint region

Feng HU, Bo WU, Youmin HU, Tielin SHI

《机械工程前沿（英文）》 2009年第4卷第3期页码 289-299 doi: 10.1007/s11465-009-0064-3

摘要： The paper proposes an identification method of the dynamic stiffness matrix of a bearing joint region on the basis of theoretical analysis and experiments. The author deduces an identification model of the dynamic stiffness matrix from the synthetic substructure method. The dynamic stiffness matrix of the bearing joint region can be identified by measuring the matrix of frequency response function (FRFs) of the substructure (axle) and whole structure (assembly of the axle, bearing, and bearing housing) in different positions. Considering difficulty in measuring angular displacement, applying moment, and directly measuring relevant FRFs of rotational degree of freedom, the author employs an accurately calibrated finite element model of the unconstrained structure for indirect estimation. With experiments and simulation analysis, FRFs related with translational degree of freedom, which is estimated through the finite element model, agrees with experimental results, and there is very high reliability in the identified dynamic stiffness matrix of the bearing joint region.

关键词： frequency response function (FRFs) dynamic stiffness finite element synthetic substructure method joint region

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基于核空间投影和联合表征的跳频信号辐射源指纹特征识别 Research Articles

Ping SUI, Ying GUO, Kun-feng ZHANG, Hong-guang LI

《信息与电子工程前沿（英文）》 2019年第20卷第8期页码 1133-1146 doi: 10.1631/FITEE.1800025

摘要：跳频作为扩频通信的一种常用技术，以其截获概率低、抗干扰能力强和保密性好等优点，在雷达和通信系统中得到广泛应用。然而，非合作条件下的跳频信号辐射源识别作为一大难题，不仅由于其对噪声影响敏感，信号的非线性、非高斯性和非平稳性使得很难在其原始信号空间实现跳频信号分类识别。现有的一些分类识别算法，如稀疏表征分类算法（SRC），仅使用单个信号样本而非整体样本表征测试数据，过分强调稀疏特性而忽略信号样本之间的相关性。为解决上述问题，本文提出一种基于核空间投影和联合表征的跳频信号辐射源指纹特征识别方法。该方法将核空间投影、相关特性表征以及个体分类学习融合到同一个联合表征框架，通过该框架实现辐射源信号分类识别。实际跳频信号的大量实验表明，与几种最先进的识别方法相比，所提算法具有可行性和有效性。

关键词：跳频信号；指纹特征；核函数；联合表征；辐射源识别

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Modeling and analysis of landing collision dynamics for a shipborne helicopter

Dingxuan ZHAO, Haojie YANG, Carbone GIUSEPPE, Wenhang LI, Tao NI, Shuangji YAO

《机械工程前沿（英文）》 2021年第16卷第1期页码 151-162 doi: 10.1007/s11465-020-0617-z

摘要： A Lagrange dynamic model is established based on small-angle approximation to improve the simulation model for shipborne helicopter landing collision. To describe fuselage motion effectively, the proposed model considers ship motion, the interaction of the tires with the deck, and tire slippage. A mechanism of sliding motion is built, and a real-time reliability analysis of the algorithm is implemented to validate the proposed model. Numerical simulations are also conducted under different operation conditions. Results show that the proposed dynamic model can simulate the collision motion of helicopter landing in real time. Several suggestions for helicopter pilot landing are likewise provided.

关键词： shipborne helicopter landing model Lagrange equations dynamics validation

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Effects of elastic support on the dynamic behaviors of the wind turbine drive train

Shuaishuai WANG, Caichao ZHU, Chaosheng SONG, Huali HAN

《机械工程前沿（英文）》 2017年第12卷第3期页码 348-356 doi: 10.1007/s11465-017-0420-7

摘要：

The reliability and service life of wind turbines are influenced by the complex loading applied on the hub, especially amidst a poor external wind environment. A three-point elastic support, which includes the main bearing and two torque arms, was considered in this study. Based on the flexibilities of the planet carrier and the housing, a coupled dynamic model was developed for a wind turbine drive train. Then, the dynamic behaviors of the drive train for different elastic support parameters were computed and analyzed. Frequency response functions were used to examine how different elastic support parameters influence the dynamic behaviors of the drive train. Results showed that the elastic support parameters considerably influenced the dynamic behaviors of the wind turbine drive train. A large support stiffness of the torque arms decreased the dynamic response of the planet carrier and the main bearing, whereas a large support stiffness of the main bearing decreased the dynamic response of planet carrier while increasing that of the main bearing. The findings of this study provide the foundation for optimizing the elastic support stiffness of the wind turbine drive train.

关键词： wind turbine drive train elastic support dynamic behavior frequency response function

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一种快速精确触觉碰撞检测中接触细节层次控制方法 Article

A Ram CHOI, Sung Min KIM, Mee Young SUNG

《信息与电子工程前沿（英文）》 2017年第18卷第8期页码 1117-1130 doi: 10.1631/FITEE.1500498

摘要：为实现精确稳定的触觉再现，包围体积（球体、轴对称包围盒、定向包围盒或多面体）必须尽可能紧密地填充或覆盖目标对象，来完成交互式触觉应用中的碰撞检测。本文提供了一种方法，用于创建与接触细节层次（contact levels of details, CLOD）相关的包围球体。该球体与目标对象相配合的同时，还能平衡碰撞检测的速度与精确性。所提出的方法主要包括包围球体成形以及两级碰撞检测两部分。进一步说，包围球体成形可分为2步：创建球体和聚类球体；两级碰撞检测也包括2个阶段：球体的快速检测以及精确检测。首先，通过包围球体的创建实现球体碰撞检测中的初始快速探测。一旦探测到碰撞，可通过检查碰撞边界内网格与触觉点的间距来实现更精确的检测效果。为实现这种精细层级的检测，需要定义一种特殊的包围体积数据结构来囊括球体内的全部网格信息。我们通过一系列实现检验了所提出方法的有效性和性能表现，结果表明所提出算法的速度和精确度可以满足触觉仿真的需要。通过球体聚类来保证检测速度，通过基于体素的直接碰撞检测来保证检测精确度。通过基于距离的聚类，所提出的方法在CLOD方面仍保持了其独创性。

关键词：碰撞检测；触觉再现；包围球体；聚类；接触细节层次

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基于改进粒子群算法优化的PID控制器在协同碰撞避免系统中的应用 Article

Xing-chen WU, Gui-he QIN, Ming-hui SUN, He YU, Qian-yi XU

《信息与电子工程前沿（英文）》 2017年第18卷第9期页码 1385-1395 doi: 10.1631/FITEE.1601427

摘要：为解决将PID控制器引入协同碰撞避免（cooperative collision avoidance system，CCAS）的研究中存在的不能合理优化PID控制器，以及对车辆行驶稳定性、舒适性及燃油经济性研究不足的问题

关键词：协同碰撞避免系统；改进的粒子群算法；PID控制器；行驶舒适性；燃油经济性

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A frequency error estimation for isogeometric analysis of Kirchhoff–Love cylindrical shells

《结构与土木工程前沿（英文）》 doi: 10.1007/s11709-023-0006-x

摘要： A frequency error estimation is presented for the isogeometric free vibration analysis of Kirchhoff–Love cylindrical shells using both quadratic and cubic basis functions. By analyzing the discrete isogeometric equations with the aid of harmonic wave assumption, the frequency error measures are rationally derived for the quadratic and cubic formulations for Kirchhoff–Love cylindrical shells. In particular, the governing relationship of the continuum frequency for Kirchhoff–Love cylindrical shells is naturally embedded into the frequency error measures without the need of explicit frequency expressions, which usually are not trivial for the shell problems. In accordance with these theoretical findings, the 2nd and 4th orders of frequency accuracy are attained for the isogeometric schemes using quadratic and cubic basis functions, respectively. Numerical results not only thoroughly verify the theoretical convergence rates of frequency solutions, but also manifest an excellent magnitude match between numerical and theoretical frequency errors for the isogeometric free vibration analysis of Kirchhoff–Love cylindrical shells.

关键词： isogeometric analysis Kirchhoff–Love cylindrical shell free vibration frequency error convergence

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Dynamic response of precast segmental bridge columns under heavy truck impact

《结构与土木工程前沿（英文）》 2023年第17卷第3期页码 327-349 doi: 10.1007/s11709-023-0911-z

摘要： Considering the wide application of precast segmental bridge columns (PSBCs) in engineering practice, impact-resistant performance has gained significant attention. However, few studies have focused on PSBCs subjected to high-energy impacts caused by heavy truck collisions. Therefore, the behavior of PSBCs under a heavy truck impact was investigated in this study using high-fidelity finite element (FE) models. The detailed FE modeling methods of the PSBCs and heavy trucks were validated against experimental tests. The validated modeling methods were employed to simulate collisions between PSBCs and heavy trucks. The simulation results demonstrated that the engine and cargo caused two major peak impact forces during collision. Subsequently, the impact force, failure mode, displacement, and internal force of the PSBCs under heavy truck impacts were scrutinized. An extensive study was performed to assess the influence of the section size, truck weight, impact velocity, and number of precast segments on the impact responses. The truck weight was found to have a minor effect on the engine impact force. Damage was found to be localized at the bottom of the three segments, with the top remaining primarily undamaged. This parametric study demonstrated that larger cross-sections may be a preferred option to protect PSBCs against the impact of heavy trucks.

关键词： precast segmental bridge columns heavy truck collision dynamic response