Search | Engineering

订阅投稿

首页工程期刊工程焦点工程成就工程前沿关于我们 English

资源类型

期刊论文 102

会议视频 3

年份

2023 8

2022 7

2021 10

2020 7

2019 9

2018 7

2017 4

2016 6

2015 3

2014 4

2013 2

2012 9

2011 4

2010 1

2009 1

2008 3

2007 6

2006 3

2004 2

2003 1

展开︾

关键词

扫描格式转换 3

运动估计 3

运动补偿 3

人工智能 2

能源 2

运动规划 2

Hilare 机器人 1

三塔两跨悬索桥 1

下肢外骨骼机器人；人机交互；运动学习；轨迹生成；运动基元；黑盒优化 1

不可否认协议；公平性分析；概率模型检测；PRISM 1

不确定性 1

中间塔鞍座 1

主动控制 1

交流永磁同步电机；滑模控制器；扩张状态观测器；鲁棒控制；运动控制 1

仲裁机制 1

仿生机器人 1

优化设计 1

作战系统 1

保持边缘的自适应滤波器 1

展开︾

检索范围：

排序：展示方式：

Novel probabilistic rolling regular tetrahedron mechanism

Yonghan GUAN, Yan’an YAO, Chao LIU, Ruiming LI

《机械工程前沿（英文）》 2021年第16卷第2期页码 363-378 doi: 10.1007/s11465-020-0628-9

摘要： With recent relevant publications on stochastic motion robots in , , and other journals, research on such robots has gained increasing attention. However, theoretical and applied research on stochastic motion in the field of robotics and mechanisms face many challenges due to the uncertainty of stochastic motion. Currently, a large gap remains in the research of stochastic motion mechanism. In this study, a novel mechanism that can conduct probabilistic rolling is proposed to reach a designated position and achieve overlying movement over a particular area. The mechanism consists of a regular tetrahedron frame, a central node, and four connecting linear actuators. According to mobility and kinematic analyses, the mechanism can implement probabilistic rolling. Each rolling gait has three probable rolling directions, and the mechanism rolls in one of the three directions in probability. A kinematic simulation is conducted, and a control method is proposed on the basis of the moving path analysis. Furthermore, the mathematical principle of probabilistic rolling is revealed in terms of probability theory and statistics. Lastly, a prototype is fabricated. To achieve the rolling function, the design of the linear actuators is improved, and the extension ratio is increased from 0.58 to 1.13. Then, tests are conducted. In a 4 m test site, the mechanism makes 11 moves to reach the target position and covers 29.25% of the site.

关键词： mobile mechanism probabilistic motion rolling mechanism stochastic motion

HTML PDF 收藏

中国核电工程场地设计地震动参数确定相关问题

李小军,贺秋梅,侯春林

《中国工程科学》 2013年第15卷第4期页码 75-82

摘要：

基于中国核电工程选址和建设的实际工作，探讨了核电工程场地设计地震动参数确定几个环节中的关键问题，包括不同地震危险性分析方法的采用、地震动衰减关系的选取和设计地震动参数的综合取值等。分析了地震动衰减关系不确定性和弥散地震衰减关系等问题处理方式的变迁，比较分析了地震危险性分析确定性方法中构造地震、弥散地震的计算结果和概率方法计算结果的差异及对设计地震动参数确定的控制作用。研究表明：a.综合考虑地震危险性分析的确定性方法和概率方法的计算结果已成为中国核电工程场地地震安全性评价中确定设计地震动参数的基本思路，其中弥散地震是一个需要特殊考虑的问题；b.确定性方法和概率方法计算结果对场地设计地震动参数的控制作用受区域地震活动性强弱的影响；c.在地震活动性较弱的地区，确定性方法特别是弥散地震计算结果基本上控制着场地设计地震动参数的取值，而在地震活动性相对较强的地区，更倾向于由概率方法计算结果控制。

关键词：核电厂设计地震动确定性方法概率方法地震动衰减关系弥散地震不确定性

HTML PDF 收藏

Risk-based probabilistic thermal-stress analysis of concrete arch dams

Narjes SOLTANI, Mohammad ALEMBAGHERI, Mohammad Houshmand KHANEGHAHI

《结构与土木工程前沿（英文）》 2019年第13卷第5期页码 1007-1019 doi: 10.1007/s11709-019-0521-y

摘要： The probabilistic risk of arch dam failure under thermal loading is studied. The incorporated uncertainties, which are defined as random variables, are associated with the most affecting structural (material) properties of concrete and thermal loading conditions. Karaj arch dam is selected as case study. The dam is numerically modeled along with its foundation in three-dimensional space; the temperature and thermal stress distribution is investigated during the operating phase. The deterministic thermal finite element analysis of the dam is combined with the structural reliability methods in order to obtain thermal response predictions, and estimate the probability of failure in the risk analysis context. The tensile overstressing failure mode is considered for the reliability analysis. The thermal loading includes ambient air and reservoir temperature variations. The effect of solar radiation is considered by an increase in the ambient temperatures. Three reliability methods are employed: the first-order second-moment method, the first-order reliability method, and the Monte-Carlo simulation with Latin Hypercube sampling. The estimated failure probabilities are discussed and the sensitivity of random variables is investigated. Although most of the studies in this line of research are used only for academic purposes, the results of this investigation can be used for both academic and engineering purposes.

关键词： arch dams probabilistic analysis thermal stress sensitivity reliability

HTML PDF 收藏

Application of probabilistic risk assessment at a coking plant site contaminated by Polycyclic Aromatic

XIA Tianxiang,JIANG Lin,JIA Xiaoyang,ZHONG Maosheng,LIANG Jing

《环境科学与工程前沿（英文）》 2014年第8卷第3期页码 441-450 doi: 10.1007/s11783-013-0572-6

摘要： Application of Probabilistic Risk Assessment (PRA) and Deterministic Risk Assessment (DRA) at a coking plant site was compared. By DRA, Hazard Quotient (HQ) following exposure to Naphthalene (Nap) and Incremental Life Cancer Risk (ILCR) following exposure to Benzo(a)pyrene (Bap) were 1.87 and 2.12 × 10 . PRA revealed valuable information regarding the possible distribution of risk, and risk estimates of DRA located at the 99.59th and 99.76th percentiles in the risk outputs of PRA, which indicated that DRA overestimated the risk. Cleanup levels corresponding acceptable HQ level of 1 and ILCR level of 10 were also calculated for both DRA and PRA. Nap and Bap cleanup levels were 192.85 and 0.14 mg·kg by DRA, which would result in only 0.25% and 0.06% of the exposed population to have a risk higher than the acceptable risk, according to the outputs of PRA. The application of PRA on cleanup levels derivation would lift the cleanup levels 1.9 times for Nap and 2.4 times for Bap than which derived by DRA. For this coking plant site, the remediation scale and cost will be reduced in a large portion once the method of PRA is used. Sensitivity analysis was done by calculating the contribution to variance for each exposure parameter and it was found that contaminant concentration in the soil ( ), exposure duration ( ), total hours spent outdoor per day ( ), soil ingestion rate ( ), the air breathing rate ( ) and bodyweight ( ) were the most important parameters for risk and cleanup levels calculations.

关键词： Probabilistic Risk Assessment (PRA) a coking plant risk cleanup level sensitivity analysis polycyclic aromatic hydrocarbons (PAHs)

HTML PDF 收藏

针对下肢外骨骼机器人的基于概率运动基元的黑盒优化运动学习 Research Article

王嘉琪,高永卓,吴冬梅,董为

《信息与电子工程前沿（英文）》 2023年第24卷第1期页码 104-116 doi: 10.1631/FITEE.2200065

摘要：外骨骼作为一种可穿戴的机器人，通过拟人化的构型直接传递机械动力来辅助或增强穿戴者运动。当外骨骼用于促进穿戴者的运动时，运动生成过程通常在高层控制中发挥重要作用。该领域的主要挑战之一是实时生成符合人类意图且可以适应不同情况的参考轨迹。在本文中，我们首先提出了一种基于概率运动基元（ProMP）的下肢外骨骼运动建模方法，它是一种用于生成运动轨迹的新型且强大的代表性工具。为了在不同穿戴者使用外骨骼时使轨迹适应不同情况，我们接着提出了一种基于黑盒优化PIBB结合ProMP的新型运动学习方案。运动模型首先由ProMP离线学习，它可以生成参考轨迹供外骨骼控制器在线使用，再采用PIBB在线学习和更新模型，提供了系统的自适应能力，消除了不确定性的影响。使用下肢外骨骼HEXO对六名受试者进行的模拟和实验证明了所提出方法的有效性。

关键词：下肢外骨骼机器人；人机交互；运动学习；轨迹生成；运动基元；黑盒优化

HTML PDF 收藏

Cumulant-based correlated probabilistic load flow considering photovoltaic generation and electric vehicle

Nitesh Ganesh BHAT, B. Rajanarayan PRUSTY, Debashisha JENA

《能源前沿（英文）》 2017年第11卷第2期页码 184-196 doi: 10.1007/s11708-017-0465-7

摘要： This paper applies a cumulant-based analytical method for probabilistic load flow (PLF) assessment in transmission and distribution systems. The uncertainties pertaining to photovoltaic generations and aggregate bus load powers are probabilistically modeled in the case of transmission systems. In the case of distribution systems, the uncertainties pertaining to plug-in hybrid electric vehicle and battery electric vehicle charging demands in residential community as well as charging stations are probabilistically modeled. The probability distributions of the result variables (bus voltages and branch power flows) pertaining to these inputs are accurately established. The multiple input correlation cases are incorporated. Simultaneously, the performance of the proposed method is demonstrated on a modified Ward-Hale 6-bus system and an IEEE 14-bus transmission system as well as on a modified IEEE 69-bus radial and an IEEE 33-bus mesh distribution system. The results of the proposed method are compared with that of Monte-Carlo simulation.

关键词： battery electric vehicle extended cumulant method photovoltaic generation plug-in hybrid electric vehicle probabilistic load flow

HTML PDF 收藏

control strategy using tuned liquid dampers to reduce displacement demands of base-isolated structures: a probabilistic

Parham SHOAEI, Houtan Tahmasebi OROMI

《结构与土木工程前沿（英文）》 2019年第13卷第4期页码 890-903 doi: 10.1007/s11709-019-0524-8

摘要： This paper investigates a hybrid structural control system using tuned liquid dampers (TLDs) and lead-rubber bearing (LRB) systems for mitigating earthquake-induced vibrations. Furthermore, a new approach for taking into account the uncertainties associated with the steel shear buildings is proposed. In the proposed approach, the probabilistic distributions of the stiffness and yield properties of stories of a set of reference steel moment frame structures are derived through Monte-Carlo sampling. The approach is applied to steel shear buildings isolated with LRB systems. The base isolation systems are designed for different target base displacements by minimizing a relative performance index using Genetic Algorithm. Thereafter, the base-isolated structures are equipped with TLDs and a combination of the base and TLD properties is sought by which the maximum reduction occurs in the base displacement without compromising the performance of the system. In addition, the effects of TLD properties on the performance of the system are studied through a parametric study. Based on the analyses results, the base displacement can be reduced 23% by average, however, the maximum reduction can go beyond 30%.

关键词： tuned liquid damper lead-rubber bearing system probabilistic framework steel shear building relative performance index Monte-Carlo sampling

HTML PDF 收藏

An interval joint-probabilistic programming method for solid waste management: a case study for the city

Yi XU, Shunze WU, Hongkuan ZANG, Guiguang HOU

《环境科学与工程前沿（英文）》 2014年第8卷第2期页码 239-255 doi: 10.1007/s11783-013-0536-x

摘要： Currently, environmental protection and resources conservation continue to be challenges faced by solid-waste managers in China. These challenges are being further compounded by rapid socioeconomic development and population growth associated with increased waste generation rates and decreased waste disposal capacities. In response to these challenges, an interval joint-probabilistic mixed-integer programming (IJMP) method is developed for supporting long-term planning of waste management activities in the city of Tianjin, which is one of the largest municipalities in the northern part of China. In the IJMP, joint probabilistic constraints are introduced into an interval-parameter mixed-integer programming framework, such that uncertainties presented in terms of interval values and random variables can be reflected. Moreover, a number of violation levels for the waste-management-capacity constraints are examined, which can facilitate in-depth analyses of tradeoffs among economic objective and system-failure risk. The results indicate that reasonable solutions have been generated. They are valuable for supporting the adjustment of the city’s existing waste-management practices and the long-term planning of the city’s waste-management facilities.

关键词： interval analysis mixed integer joint probabilistic constraint planning uncertainty waste management

HTML PDF 收藏

Offline motion planning and simulation of two-robot welding coordination

Tie ZHANG, Fan OUYANG

《机械工程前沿（英文）》 2012年第7卷第1期页码 81-92 doi: 10.1007/s11465-012-0309-4

摘要：

This paper focuses on the two-robot welding coordination of complex curve seam which means one robot grasp the workpiece, the other hold the torch, the two robots work on the same workpiece simultaneously. This paper builds the dual-robot coordinate system at the beginning, and three point calibration method of two robots’ relative base coordinate system is presented. After that, the non master/slave scheme is chosen for the motion planning, the non master/slave scheme sets the poses versus time function of the point u on the workpiece, and calculates the two robot end effecter trajectories through the constrained relationship matrix automatically. Moreover, downhand welding is employed which can guarantee the torch and the seam keep in good contact condition all the time during the welding. Finally, a Solidworks-SimMechanics simulation platform is established, and a simulation of curved steel pipe welding is conducted. The results of the simulation illustrate the welding process can meet the requirements of downhand welding, the joint displacement curves are smooth and continuous and no joint velocities are out of working scope.

关键词： complex curve seam two robots coordinated welding motion planning

HTML PDF 收藏

Seismic performance of viaducts with probabilistic method

ZHU Xi, WANG Jianmin

《结构与土木工程前沿（英文）》 2007年第1卷第3期页码 267-273 doi: 10.1007/s11709-007-0034-y

摘要： Due to the uncertainty of both ground motions and structural capacity, it is necessary to consider the seismic performance of viaduct structures using the probabilistic method. The risk is quantified by a procedure on the basis of a numerical determination of the fragility curves. A group of ground motions, Large Magnitude-Short Distance Bin (LMSR-N), selected specially due to its response spectra, is accorded well with the corresponding spectra of the Chinese code for seismic design. The characteristic values of the curvature ductility factors for the serviceability and the damage control limit states are obtained, and two equations for estimating the characteristic values of the curvature ductility factors are developed through regression analysis. Then, the serviceability and damage control limit states were proposed. Three damage states were constituted according the results of the experiment by Pacific Earthquake Engineering Research (PEER) Center. The analytical fragility curves were obtained specifically, using both Capacity Spectrum Method (CSM) (non-linear static) analysis and Ineremental Dynamic Method (IDM) (non-linear dynamic) analysis, respectively, in this paper. The structural fragility curves developed by CSM method can help make the structural analysis simple and quick, avoiding the implementation of the dynamic response history analysis (RHA). Although the dynamic RHA requires a lot of complicated analysis for the structure, the results from RHA are reliable and accurate. Fragility curves are powerful tools for use in performance-based seismic bridge design.

关键词： uncertainty Earthquake Engineering regression analysis accurate fragility

HTML PDF 收藏

Probabilistic analysis of secant piles with random geometric imperfections

《结构与土木工程前沿（英文）》 2021年第15卷第3期页码 682-695 doi: 10.1007/s11709-021-0703-2

摘要： The failure to achieve minimum design overlap between secant piles compromises the ability of a structure to perform as designed, resulting in water leakage or even ground collapse. To establish a more realistic simulation and provide guidelines for designing a safe and cost-effective secant-pile wall, a three-dimensional model of a secant pile, considering the geometric imperfections of the diameter and direction of the borehole, is introduced. An ultrasonic cross-hole test was performed during the construction of secant piles in a launching shaft in Beijing, China. Based on the test results, the statistical characteristics of the pile diameters and orientation parameters were obtained. By taking the pile diameter D, inclination angle β, and azimuth angle α as random variables, Monte Carlo simulations were performed to discuss the influence of different design parameters on the probability density functions of the overlap of secant piles. The obtained results show that the randomness of the inclination angle and pile diameter can be well described by a normal distribution, whereas the azimuth angle is more consistent with a uniform distribution. The integrity of the secant-pile wall can be overestimated without considering the uncertainty of geometric imperfections. The failure of the secant-pile wall increases substantially with increasing spatial variability in drilling inclination and diameter. A design flowchart for pile spacing under the target safety level is proposed to help engineers design a safe and economical pile wall.

关键词： secant piles ultrasonic cross-hole testing probabilistic analysis reliability-based design random imperfections

HTML PDF 收藏

topology optimization of hinge-free compliant mechanisms with material uncertainties based on a non-probabilistic

Junjie ZHAN, Yangjun LUO

《机械工程前沿（英文）》 2019年第14卷第2期页码 201-212 doi: 10.1007/s11465-019-0529-y

摘要： This paper presents a new robust topology optimization framework for hinge-free compliant mechanisms with spatially varying material uncertainties, which are described using a non-probabilistic bounded field model. Bounded field uncertainties are efficiently represented by a reduced set of uncertain-but-bounded coefficients on the basis of the series expansion method. Robust topology optimization of compliant mechanisms is then defined to minimize the variation in output displacement under constraints of the mean displacement and predefined material volume. The nest optimization problem is solved using a gradient-based optimization algorithm. Numerical examples are presented to illustrate the effectiveness of the proposed method for circumventing hinges in topology optimization of compliant mechanisms.

关键词： compliant mechanisms robust topology optimization hinges uncertainty bounded field

HTML PDF 收藏

Synthesis of Intermittent-Motion Linkages with Slight Difference in Length Between Links

CHEN Xin-bo, YU Zhen

《机械工程前沿（英文）》 2006年第1卷第1期页码 76-79 doi: 10.1007/s11465-005-0007-6

摘要：

The design of intermittent-motion linkages using traditional methods is usually complicated. In this paper, (1) a new method for realizing intermittent motion, using linkages with a slight difference in length between links, is studied; (2) some new types of intermittent-motion linkages and their software for visual analysis and design are developed; and (3) influences of some design parameters on intermittent-motion characteristics are clarified. Results confirmed that the theory and the software are useful, making the synthesis of intermittent-motion linkages clear and easy.

关键词： synthesis useful intermittent intermittent-motion traditional

HTML PDF 收藏

Probabilistic model for vessel-bridge collisions in the Three Gorges Reservoir

Bo GENG , Hong WANG , Junjie WANG ,

《结构与土木工程前沿（英文）》 2009年第3卷第3期页码 279-285 doi: 10.1007/s11709-009-0044-z

摘要： Based on a field observation on vessel transit path of three bridges over the Yangtze River in the Three Gorges Reservoir, and an analysis of the geometric probabilistic model of transiting vessels in collision probability calculation, the aberrancy angle and vessel velocity probabilistic model related with impact force, a probabilistic model is established and also verified by goodness-of-fit test. The vessel transit path distribution can be expressed by the normal distribution model. For the Three Gorges Reservoir, the mean and standard deviation adopt 0.2 and 0.1, respectively ( is the channel width). The aberrancy angle distribution of vessels accepts maximum I distribution model, and its distribution parameters can be taken as 0.314 and 4.354. The velocity distribution of up-bound and down-bound vessels can also be expressed by the normal distribution model.

关键词： vessel-bridge collision probabilistic model parameter statistics

HTML PDF 收藏

Design and modeling of continuum robot based on virtual-center of motion mechanism

《机械工程前沿（英文）》 2023年第18卷第2期 doi: 10.1007/s11465-022-0739-6

摘要： Continuum robot has attracted extensive attention since its emergence. It has multi-degree of freedom and high compliance, which give it significant advantages when traveling and operating in narrow spaces. The flexural virtual-center of motion (VCM) mechanism can be machined integrally, and this way eliminates the assembly between joints. Thus, it is well suited for use as a continuum robot joint. Therefore, a design method for continuum robots based on the VCM mechanism is proposed in this study. First, a novel VCM mechanism is formed using a double leaf-type isosceles-trapezoidal flexural pivot (D-LITFP), which is composed of a series of superimposed LITFPs, to enlarge its stroke. Then, the pseudo-rigid body (PRB) model of the leaf is extended to the VCM mechanism, and the stiffness and stroke of the D-LITFP are modeled. Second, the VCM mechanism is combined to form a flexural joint suitable for the continuum robot. Finally, experiments and simulations are used to validate the accuracy and validity of the PRB model by analyzing the performance (stiffness and stroke) of the VCM mechanism. Furthermore, the motion performance of the designed continuum robot is evaluated. Results show that the maximum stroke of the VCM mechanism is approximately 14.2°, the axial compressive strength is approximately 1915 N/mm, and the repeatable positioning accuracies of the continuum robot is approximately ±1.47° (bending angle) and ±2.46° (bending direction).

关键词： VCM mechanism continuum robot flexural joint pseudo-rigid body model cable-driven