资源类型

期刊论文 146

年份

2023 8

2022 12

2021 11

2020 12

2019 10

2018 8

2017 12

2016 8

2015 11

2014 4

2013 5

2012 9

2011 7

2010 2

2009 8

2008 2

2007 5

2006 2

2002 1

2000 1

展开 ︾

关键词

工程项目 2

9 %~12 % Cr 钢 1

&prime 1

&gamma 1

CDMA 1

Hilare 机器人 1

M23C6 碳化物 1

三塔两跨悬索桥 1

上下行解耦;用户接入;资源划分;异构蜂窝网络;联合博弈 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

业主 1

中俄火星联合探测计划 1

中国和巴西 1

中国空间探测 1

中间塔鞍座 1

二维波达角估计;信道冲击响应估计;信号检测;均匀矩形阵列;大规模天线 1

交通工程 1

展开 ︾

检索范围:

排序: 展示方式:

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    

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    

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    

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)    

Technology and system of constraint programming for industry production scheduling

Yarong CHEN, Zailin GUAN, Yunfang PENG, Xinyu SHAO, Muhammad HASSEB

《机械工程前沿(英文)》 2010年 第5卷 第4期   页码 455-464 doi: 10.1007/s11465-010-0106-x

摘要: The use of techniques and system of constraint programming enables the implementation of precise, flexible, efficient, and extensible scheduling systems. It has been identified as a strategic direction and dominant form for the application into planning and scheduling of industrial production. This paper systematically introduces the constraint modeling and solving technology for production scheduling problems, including various real-world industrial applications based on the Chip system of Cosytec Company. We trend of some concrete technology, such as modeling, search, constraint propagation, consistency, and optimization of constraint programming for scheduling problems. As a result of the application analysis, a generic application framework for real-life scheduling based on commercial constraint propagation (CP) systems is proposed.

关键词: constraint programming     production scheduling     constraint propagation     search     consistency     optimization    

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    

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    

Analytical algorithms of compressive bending capacity of bolted circumferential joint in metro shield

《结构与土木工程前沿(英文)》   页码 901-914 doi: 10.1007/s11709-023-0915-8

摘要: The integrity and bearing capacity of segment joints in shield tunnels are associated closely with the mechanical properties of the joints. This study focuses on the mechanical characteristics and mechanism of a bolted circumferential joint during the entire bearing process. Simplified analytical algorithms for four stress stages are established to describe the bearing behaviors of the joint under a compressive bending load. A height adjustment coefficient, α, for the outer concrete compression zone is introduced into a simplified analytical model. Factors affecting α are determined, and the degree of influence of these factors is investigated via orthogonal numerical simulations. The numerical results show that α can be specified as approximately 0.2 for most metro shield tunnels in China. Subsequently, a case study is performed to verify the rationality of the simplified theoretical analysis for the segment joint via numerical simulations and experiments. Using the proposed simplified analytical algorithms, a parametric investigation is conducted to discuss the factors affecting the ultimate compressive bending capacity of the joint. The method for optimizing the joint flexural stiffness is clarified. The results of this study can provide a theoretical basis for optimizing the design and prediciting the damage of bolted segment joints in shield tunnels.

关键词: shield tunnel     segment joint     joint structural model     failure mechanism    

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    

Finite element analysis on the seismic behavior of side joint of Prefabricated Cage System in prefabricated

Yunlin LIU, Shitao ZHU

《结构与土木工程前沿(英文)》 2019年 第13卷 第5期   页码 1095-1104 doi: 10.1007/s11709-019-0538-2

摘要: The Prefabricated Cage System (PCS) has the advantages of high bearing capacity and good ductility. Meanwhile, it is convenient for factory production and it is beneficial to the cost savings, construction period shortening. Side joint is the weak region of PCS concrete frame and has great influence on seismic behavior of the whole structure. Thus systematically study on the seismic behavior of PCS concrete side joint is necessary. This paper presents a finite element study on behavior of the side joint under seismic loading. In the finite element model, PCS concrete and the reinforced concrete (RC) is modeled by the solid element and fiber-beam element, respectively. The numerical results is compared with the experimental results and it is found that the results of model based on fiber-beam element is in better agreement with the experimental results than solid element model. In addition, the overall seismic behavior of the side joints in PCS concrete is better than that of the RC with the same strength.

关键词: PCS concrete side joint     numerical simulation     fiber-beam element joint model     solid element joint model     seismic behavior    

Recent development in low-constraint fracture toughness testing for structural integrity assessment of

Jidong KANG, James A. GIANETTO, William R. TYSON

《机械工程前沿(英文)》 2018年 第13卷 第4期   页码 546-553 doi: 10.1007/s11465-018-0501-2

摘要:

Fracture toughness measurement is an integral part of structural integrity assessment of pipelines. Traditionally, a single-edge-notched bend (SE(B)) specimen with a deep crack is recommended in many existing pipeline structural integrity assessment procedures. Such a test provides high constraint and therefore conservative fracture toughness results. However, for girth welds in service, defects are usually subjected to primarily tensile loading where the constraint is usually much lower than in the three-point bend case. Moreover, there is increasing use of strain-based design of pipelines that allows applied strains above yield. Low-constraint toughness tests represent more realistic loading conditions for girth weld defects, and the corresponding increased toughness can minimize unnecessary conservatism in assessments. In this review, we present recent developments in low-constraint fracture toughness testing, specifically using single-edge-notched tension specimens, SENT or SE(T). We focus our review on the test procedure development and automation, round-robin test results and some common concerns such as the effect of crack tip, crack size monitoring techniques, and testing at low temperatures. Examples are also given of the integration of fracture toughness data from SE(T) tests into structural integrity assessment.

关键词: fracture toughness     constraint effect     single-edge-notched tension test     pipeline     structural integrity assessment    

Development of rocking constraint device with vertical damping capacity for three-dimensional base-isolated

《结构与土木工程前沿(英文)》 2023年 第17卷 第3期   页码 350-367 doi: 10.1007/s11709-022-0923-0

摘要: A new rocking constraint device (RCD) is developed for three-dimensional (3D) base-isolated frame structures by connecting a custom-designed cylinder pair to provide vertical damping with replaceable damping components installed outside the cylinders when the superstructure undergoes translational motion, and rocking constraint capacity when the superstructure is susceptible to rocking. Theoretical formulas for calculating the damping and rocking constraint stiffness of the RCD are proposed. Two series of sinusoidal loading tests are conducted at different loading frequencies and amplitudes to verify the damping and rocking constraint performance of the RCD. The test results show that the cylinder without orifices on its piston can provide the desired damping with a replaceable damping component, and that the RCD can effectively suppress rocking. Although the vertical stiffness of an individual cylinder is affected by the location of the replaceable damping component and loading frequency, the average vertical stiffness of the two cylinders, which determines the rocking constraint stiffness of the RCD, is independent of the two factors. Comparisons of the test and theoretical results indicate that the errors of the proposed formulas for calculating the damping and rocking constraint stiffness of the RCD do not exceed 12.9% and 11.0%, respectively.

关键词: three-dimensional isolation     rocking behavior     rocking constraint device     replaceable damping component     sinusoidal test    

基于随机有限集的非齐次马尔可夫链联合概率数据关联滤波器 Research Articles

朱昀1,2,梁爽3,吴晓军1,2,杨红红1,2

《信息与电子工程前沿(英文)》 2021年 第22卷 第8期   页码 1114-1126 doi: 10.1631/FITEE.2000209

摘要: 提出一种启发式方法,通过随机有限集理论优化数据关联跟踪算法的后验密度。具体而言,提出一种改进的联合概率数据关联滤波方法,即最近邻集合联合概率数据关联方法(NNSJPDA)。为提高边缘化的准确性,利用一种基于Kullback-Leibler散度的最近邻方法,对所有可能的数据关联事件中的目标标签进行转换。此外,进一步考虑目标标签向量的分布。后验密度转换后,可得到目标标签向量的转移矩阵。该转移矩阵随时间变化,使得目标标签向量分布的传播遵循非齐次马尔可夫链。证明了该链本质上是双随机的,并推导了相应定理。通过举例和仿真,验证了所提方法的有效性。本文结果可推广到相同随机有限集框架下的其他数据关联方法。

关键词: 目标跟踪;滤波理论;随机有限集理论;贝叶斯方法;马尔可夫链    

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    

Research on constraint-based virtual assembly technologies

YANG Rundang, WU Dianliang, FAN Xiumin, YAN Juanqi

《机械工程前沿(英文)》 2007年 第2卷 第2期   页码 243-249 doi: 10.1007/s11465-007-0043-5

摘要: To realize a constraint-based virtual assembly operation, the unified representations of the assembly constraint, the equivalent relation between the constraint and the degree of freedom (DOF), and the movement DOF reduction in a virtual environment are proposed. Several algorithms about the constraint treatment are submitted. First, the automatic recognition algorithm based on the assembly relation is used to determine the position and orientation relation between two geometry elements of constraint whether they meet the given errors. Second, to satisfy the new constraint, according to the positing solving algorithm, the position and orientation of an active part are modified with minimal adjustment after the part has satisfied the affirmed constraints. Finally, the algorithm of movement navigation based on the generalized coordinate system is put forward, and the part movement is guided. These algorithms have been applied to the integrated virtual assembly environment (IVAE) system. Experiments have indicated that these algorithms have well supported constraint treatments in the IVAE and realized the closer combination of the virtual and the real assembly processes.

关键词: movement DOF     recognition algorithm     assembly     orientation     combination    

标题 作者 时间 类型 操作

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

Yi XU, Shunze WU, Hongkuan ZANG, Guiguang HOU

期刊论文

Novel probabilistic rolling regular tetrahedron mechanism

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

期刊论文

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

Narjes SOLTANI, Mohammad ALEMBAGHERI, Mohammad Houshmand KHANEGHAHI

期刊论文

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

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

期刊论文

Technology and system of constraint programming for industry production scheduling

Yarong CHEN, Zailin GUAN, Yunfang PENG, Xinyu SHAO, Muhammad HASSEB

期刊论文

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

Nitesh Ganesh BHAT, B. Rajanarayan PRUSTY, Debashisha JENA

期刊论文

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

Parham SHOAEI, Houtan Tahmasebi OROMI

期刊论文

Analytical algorithms of compressive bending capacity of bolted circumferential joint in metro shield

期刊论文

Seismic performance of viaducts with probabilistic method

ZHU Xi, WANG Jianmin

期刊论文

Finite element analysis on the seismic behavior of side joint of Prefabricated Cage System in prefabricated

Yunlin LIU, Shitao ZHU

期刊论文

Recent development in low-constraint fracture toughness testing for structural integrity assessment of

Jidong KANG, James A. GIANETTO, William R. TYSON

期刊论文

Development of rocking constraint device with vertical damping capacity for three-dimensional base-isolated

期刊论文

基于随机有限集的非齐次马尔可夫链联合概率数据关联滤波器

朱昀1,2,梁爽3,吴晓军1,2,杨红红1,2

期刊论文

Probabilistic analysis of secant piles with random geometric imperfections

期刊论文

Research on constraint-based virtual assembly technologies

YANG Rundang, WU Dianliang, FAN Xiumin, YAN Juanqi

期刊论文