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Real drive cycles analysis by ordered power methodology applied to fuel consumption, CO

Pol Masclans Abelló, Vicente Medina Iglesias, M. Antonia de los Santos López, Jesús Álvarez-Flórez

《环境科学与工程前沿(英文)》 2021年 第15卷 第1期 doi: 10.1007/s11783-020-1296-z

摘要: Abstract • New method named CAbOP is presented based on ordering data according to power. • Three emission models are used and their emission results compared. • Emissions data are analyzed in real driving cycles under CAbOP criteria. • Methodology to collect data and reconstruct lost data in real urban driving cycles. In this work three fuel consumption and exhaust emission models, ADVISOR, VT-MICRO and the European Environmental Agency Emission factors, have been used to obtain fuel consumption (FC) and exhaust emissions. These models have been used at micro-scale, using the two signal treatment methods presented. The manuscript presents: 1) a methodology to collect data in real urban driving cycles, 2) an estimation of FC and tailpipe emissions using some available models in literature, and 3) a novel analysis of the results based on delivered wheel power. The results include Fuel Consumption (FC), CO2, NOx and PM10 emissions, which are derived from the three simulators. In the first part of the paper we present a new procedure for incomplete drive cycle data treatment, which is necessary for real drive cycle acquisition in high density cities. Then the models are used to obtain second by second FC and exhaust emissions. Finally, a new methodology named Cycle Analysis by Ordered Power (CAbOP) is presented and used to compare the results. This method consists in the re-ordering of time dependant data, considering the wheel mechanical power domain instead of the standard time domain. This new strategy allows the 5 situations in drive cycles to be clearly visualized: hard breaking zone, slowdowns, idle or stop zone, sustained speed zone and acceleration zone. The complete methodology is applied in two real drive cycles surveyed in Barcelona (Spain) and the results are compared with a standardized WLTC urban cycle.

关键词: Cycle Analysis by Ordered Power (CAbOP)     Micro and macro models     Real drive cycle     NOx/PM10/CO2 emissions     Wheel mechanical power domain     Worldwide Harmonized Light-Duty Vehicles Test Cycle (WLTC)    

WEIS wheel speed real-time measuring method for VOSM

Mengyao PAN, Guixiong LIU, Xiaobin HONG, Tusheng LIN,

《机械工程前沿(英文)》 2010年 第5卷 第3期   页码 322-327 doi: 10.1007/s11465-010-0022-0

摘要: Wheel speed is one of the key parameters of vehicle operating attitude. To solve the problems in traditional wheel speed measuring methods, such as low measurement precision and the lack of real-time monitoring of the vehicle’s operating attitude, a wheel embedded intelligent sensors (WEIS) wheel speed measuring method for vehicle operating safety states monitoring (VOSM) is innovatively proposed. Radial acceleration signal is obtained through a WEIS module embedded in the hub. Using wavelet packet to implement wavelet de-noising for the non-stationary acceleration signals, and adopting short-time Fourier transform (STFT) algorithm to extract the signal characteristics, the wheel speed measurement can be achieved. The experimental result shows that under experimental conditions the speed measurement error is −2.05%, and the speed measuring response time is 0.45 s.

关键词: wheel embedded     intelligent sensing     wheel speed     monitoring    

Time-domain and frequency-domain approaches to identification of bridge flutter derivatives

Zhengqing CHEN

《结构与土木工程前沿(英文)》 2009年 第3卷 第2期   页码 173-179 doi: 10.1007/s11709-009-0034-1

摘要: Flutter derivatives are essential for flutter analysis of long-span bridges, and they are generally identified from the vibration testing data of a sectional model suspended in a wind tunnel. Making use of the forced vibration testing data of three sectional models, namely, a thin-plate model, a nearly streamlined model, and a bluff-body model, a comparative study was made to identify the flutter derivatives of each model by using a time-domain method and a frequency-domain method. It was shown that all the flutter derivatives of the thin-plate model identified with the frequency-domain method and time-domain method, respectively, agree very well. Moreover, some of the flutter derivatives of each of the other two models identified with the two methods deviate to some extent. More precisely, the frequency-domain method usually results in smooth curves of the flutter derivatives. The formulation of time-domain method makes the identification results of flutter derivatives relatively sensitive to the signal phase lag between vibration state vector and aerodynamic forces and also prone to be disturbed by noise and nonlinearity.

关键词: long-span bridges     wind-induced vibration     flutter derivatives     forced vibration test     time-domain method     frequency-domain method    

Simulation and analysis of grinding wheel based on Gaussian mixture model

Yulun CHI, Haolin LI

《机械工程前沿(英文)》 2012年 第7卷 第4期   页码 427-432 doi: 10.1007/s11465-012-0350-3

摘要:

This article presents an application of numerical simulation technique for the generation and analysis of the grinding wheel surface topographies. The ZETA 20 imaging and metrology microscope is employed to measure the surface topographies. The Gaussian mixture model (GMM) is used to transform the measured non-Gaussian field to Gaussian fields, and the simulated topographies are generated. Some numerical examples are used to illustrate the viability of the method. It shows that the simulated grinding wheel topographies are similar with the measured and can be effective used to study the abrasive grains and grinding mechanism.

关键词: grinding wheel     3D topographies measurement     Gaussian mixture model     simulation    

Fatigue and impact analysis and multi-objective optimization design of Mg/Al assembled wheel considering

《机械工程前沿(英文)》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0701-7

摘要: The multi-material assembled light alloy wheel presents an effective lightweight solution for new energy vehicles, but its riveting connection remains a problem. To address this problem, this paper proposed the explicit riveting-implicit springback-implicit fatigue/explicit impact sequence coupling simulation analysis method, analyzed the fatigue and impact performance of the punching riveting connected magnesium/aluminum alloy (Mg/Al) assembled wheel, and constructed some major evaluation indicators. The accuracy of the proposed simulation method was verified by conducting physical experiments of single and cross lap joints. The punching riveting process parameters of the assembled wheel joints were defined as design variables, and the fatigue and impact performance of the assembled wheel was defined as the optimization objective. The connection-performance integration multi-objective optimization design of the assembled wheel considering riveting residual stress was designed via Taguchi experiment, grey relational analysis, analytic hierarchy process, principal component analysis, and entropy weighting methods. The optimization results of the three weighting methods were compared, and the optimal combination of design variables was determined. The fatigue and impact performance of the Mg/Al assembled wheel were effectively improved after optimization.

关键词: magnesium/aluminum assembled wheel     riveting residual stress     fatigue analysis     impact analysis     multi-objective optimization    

Lightening structure optimization on turbine wheel of vehicular turbocharger

ZHAO Junsheng, MA Chaochen, HU Liaoping

《能源前沿(英文)》 2008年 第2卷 第4期   页码 422-426 doi: 10.1007/s11708-008-0098-y

摘要: Based on basic principle of optimization design, structure optimization of turbine is conducted using optimization module of ANSYS and APDL in order to get the minimum turbine weight. Meanwhile, the original blade profile and flow passage are maintained, and the structural strength of the turbine are guaranteed. Considering assembly technique and cast requirement, the structure of the modified turbine is determined which can save 6.91 percent of the material compared with the original one. The modified turbine not only saved material, but also gained better effect of mass distribution between the turbine and the compressor impeller. The result can provide useful reference to engineering application of turbocharger.

关键词: requirement     technique     engineering application     turbocharger     reference    

月球车叶片伸缩式步行轮的力学分析和性能优化 Article

杨璐, 蔡博文, 张荣辉, 李克宁, 张子贤, 雷洁浩, 陈百超, 王荣本

《工程(英文)》 2020年 第6卷 第8期   页码 936-943 doi: 10.1016/j.eng.2020.07.009

摘要:

在探月工程计划中,月球车的车轮系统是月球车总体设计系统的重要子系统之一。由于月表地形复杂,同时受限于月球车有限的空间,因此大大增加了车轮系统设计和优化工作的难度。本研究的主要目标是针对自主设计的月球车机械结构,建立一个原理型样机以对其性能进行优化。研究的主要工作包括:为应对月表复杂路况,提出了一种适配月球车正反四边形悬架的新型叶片伸缩式步行轮;以功耗最小化为目标,在保证障碍通过性的前提下,分析车轮运动过程中受力情况以实现对车轮的性能优化;最后,基于数字仿真和综合实验方法,验证了新型车轮系统在实际实验中可以达到按需伸缩叶片和节约能耗的效果。本文的研究成果为中国月球车的研究和开发提供了一种技术参考。

关键词: 特种智能载具     叶片伸缩式步行轮     性能优化     叶片弹簧     月球车    

Numerical simulation and experimental research on the wheel brush sampling process of an asteroid sampler

《机械工程前沿(英文)》 2023年 第18卷 第2期 doi: 10.1007/s11465-022-0732-0

摘要: To examine the environmental characteristics of the microgravity force and the weathered layer on an asteroid surface, a symmetric wheel brush asteroid sampler is proposed for the collection of particles on the asteroid surface. To study the influence of the wheel brush rotation speed on the sampling efficiency and the driving torque required for the wheel brush, the contact dynamics model between particles and sampling wheel brushes is established and a simulation and experimental verification of the sampling process are conducted. The parameter calibration of the sampled particles is studied first, and the calibrated particle parameters are used in the numerical simulation of the sampling process. The sampling results and the particle stream curves are obtained for the working conditions of different rotation speeds, and the effects of different parameter settings on the sampling efficiency are analyzed. In addition, a set of rotating symmetrical sampling wheel brush devices is built for the ground test, and the dynamic torque sensor is used to test the torque change of the wheel brush during the sampling process. The relationship between the speed of the wheel brush and the driving torque of the wheel brush motor is determined by comparing the simulation results with the test results. Results indicate that when the rotating speed of the wheel brush is faster, the sampling efficiency is higher, and the driving torque required for the sampling wheel brush is greater. Moreover, a numerical simulation analysis of the sampling process of the wheel brush sampler in a microgravity environment is conducted to determine the optimal speed condition, and the brushing test of the wheel brush sampler in the microgravity environment is verified with the drop tower method. This research proposes the structural optimization design and motor selection of a wheel brush asteroid sampler, which provides important reference value and engineering significance.

关键词: asteroid sampling     wheel brush sampler     discrete element method     parameter calibration     experimental research    

Entity and relation extraction with rule-guided dictionary as domain knowledge

《工程管理前沿(英文)》   页码 610-622 doi: 10.1007/s42524-022-0226-0

摘要: Entity and relation extraction is an indispensable part of domain knowledge graph construction, which can serve relevant knowledge needs in a specific domain, such as providing support for product research, sales, risk control, and domain hotspot analysis. The existing entity and relation extraction methods that depend on pretrained models have shown promising performance on open datasets. However, the performance of these methods degrades when they face domain-specific datasets. Entity extraction models treat characters as basic semantic units while ignoring known character dependency in specific domains. Relation extraction is based on the hypothesis that the relations hidden in sentences are unified, thereby neglecting that relations may be diverse in different entity tuples. To address the problems above, this paper first introduced prior knowledge composed of domain dictionaries to enhance characters’ dependence. Second, domain rules were built to eliminate noise in entity relations and promote potential entity relation extraction. Finally, experiments were designed to verify the effectiveness of our proposed methods. Experimental results on two domains, including laser industry and unmanned ship, showed the superiority of our methods. The F1 value on laser industry entity, unmanned ship entity, laser industry relation, and unmanned ship relation datasets is improved by +1%, +6%, +2%, and +1%, respectively. In addition, the extraction accuracy of entity relation triplet reaches 83% and 76% on laser industry entity pair and unmanned ship entity pair datasets, respectively.

关键词: entity extraction     relation extraction     prior knowledge     domain rule    

泰州大桥钢桥面铺装轮载谱研究

李洪涛,潘友强,张志祥

《中国工程科学》 2012年 第14卷 第5期   页码 85-89

摘要:

调研了江苏省内三座跨江大桥2007—2010年的交通量和交通荷载状况,利用轮载谱分析货车交通量和交通荷载状况,并推荐了江苏省内货车轮载和典型轮载比例;分析江苏省内三座跨江大桥的货车超载情况并给出了超载比例较大的车型。研究成果为泰州大桥钢桥面铺装设计研究提供了有力支持。

关键词: 跨江大桥     轮载谱     轮载类型     交通量     交通荷载    

Multidisciplinary co-design optimization of structural and control parameters for bucket wheel reclaimer

Yongliang YUAN, Liye LV, Shuo WANG, Xueguan SONG

《机械工程前沿(英文)》 2020年 第15卷 第3期   页码 406-416 doi: 10.1007/s11465-019-0578-2

摘要: Bucket wheel reclaimer (BWR) is an extremely complex engineering machine that involves multiple disciplines, such as structure, dynamics, and electromechanics. The conventional design strategy, namely, sequential strategy, is structural design followed by control optimization. However, the global optimal solution is difficult to achieve because of the discoordination of structural and control parameters. The co-design strategy is explored to address the aforementioned problem by combining the structural and control system design based on simultaneous dynamic optimization approach. The radial basis function model is applied for the planning of the rotation speed considering the relationships of subsystems to minimize the energy consumption per volume. Co-design strategy is implemented to resolve the optimization problem, and numerical results are compared with those of sequential strategy. The dynamic response of the BWR is also analyzed with different optimization strategies to evaluate the advantages of the strategies. Results indicate that co-design strategy not only can reduce the energy consumption of the BWR but also can achieve a smaller vibration amplitude than the sequential strategy.

关键词: bucket wheel reclaimer     co-design     energy-minimum optimization     sequential strategy    

Effect of cavity defect on the triaxial mechanical properties of high-performance concrete

Yanbin ZHANG; Zhe WANG; Mingyu FENG

《结构与土木工程前沿(英文)》 2022年 第16卷 第5期   页码 600-614 doi: 10.1007/s11709-022-0821-5

摘要: The stress concentration of pipe structure or cavity defect has a great effect on the mechanical properties of the high-performance concrete (HPC) members in deep underground locations. However, the behaviour of HPC with cavities under triaxial compression is not understood, especially when pressurized liquid flows into the fractures from the cavity. This study aims to investigate the effect of the cavity and the confining pressure on the failure mechanisms, strengths, and deformation properties of HPC with a new experimental scheme. In this experiment, the pressurized liquid can only contact the surface of the sample in the cavity, while the other surfaces are isolated from the pressurized liquid. To further explore the effect of the cavity, the same experiments are also conducted on sealed and unsealed intact samples without a cavity. The failure modes and stress-strain curves of all types of the samples are presented. Under various confining pressures, all the samples with a cavity suffer shear failure, and there are always secondary tensile fractures initiating from the cavity sidewall. Additionally, it can be determined from the failure modes and the stress-strain curves that the shear fractures result from the sidewall failure. Based on the different effects of the cavity on the lateral deformations in different directions, the initiation of the sidewall fracture is well predicted. The experimental results show that both the increase of the confining pressure and the decrease of the cavity size are conducive to the initiation of sidewall fracture. Moreover, the cavity weakens the strength of the sample, and this study gives a modified Power-law criterion in which the cavity size is added as an impact factor to predict the strength of the sample.

关键词: high-performance concrete     cavity     conventional triaxial compression     pressurized liquid     modified power-law criterion    

Damage identification in connections of moment frames using time domain responses and an optimization

《结构与土木工程前沿(英文)》 2021年 第15卷 第4期   页码 851-866 doi: 10.1007/s11709-021-0739-3

摘要: Damage is defined as changes to the material and/or geometric properties of a structural system, comprising changes to the boundary conditions and system connectivity, adversely affecting the system’s performance. Inspecting the elements of structures, particularly critical components, is vital to evaluate the structural lifespan and safety. In this study, an optimization-based method for joint damage identification of moment frames using the time-domain responses is introduced. The beam-to-column connection in a metallic moment frame structure is modeled by a zero-length rotational spring at both ends of the beam element. For each connection, an end-fixity factor is specified, which changes between 0 and 1. Then, the problem of joint damage identification is converted to a standard optimization problem. An objective function is defined using the nodal point accelerations extracted from the damaged structure and an analytical model of the structure in which the nodal accelerations are obtained using the Newmark procedure. The optimization problem is solved by an improved differential evolution algorithm (IDEA) for identifying the location and severity of the damage. To assess the capability of the proposed method, two numerical examples via different damage scenarios are considered. Then, a comparison between the proposed method and the existing damage identification method is provided. The outcomes reveal the high efficiency of the proposed method for finding the severity and location of joint damage considering noise effects.

关键词: damage identification     beam-to-column connection     time-domain response     optimization    

Heat transfer coefficient of wheel rim of large capacity steam turbines

SHI Jinyuan, DENG Zhicheng, YANG Yu, JUN Ganwen

《能源前沿(英文)》 2008年 第2卷 第1期   页码 20-24 doi: 10.1007/s11708-008-0015-4

摘要: A way of calculating the overall equivalent heat transfer coefficient of wheel rims of large capacity steam turbines is presented. The method and formula to calculate the mean forced convection heat-transfer coefficient of the surface of the blade and for the bottom wall of the blade passage, are introduced. The heat transmission from the blade to the rim was simplified by analogy to heat transmission in the fins. A fin heat transfer model was then used to calculate the equivalent heat transfer coefficient of the blade passage. The overall equivalent heat transfer coefficient of the wheel rim was then calculated using a cylindrical surface model. A practical calculation example was presented. The proposed method helps determine the heat transfer boundary conditions in finite element analyses of temperature and thermal stress fields of steam turbine rotors.

关键词: convection heat-transfer     capacity     heat-transfer coefficient     bottom     transmission    

Wheel tracking methods to evaluate moisture sensitivity of hot-mix asphalt mixtures

Jie HAN,Harihar Shiwakoti

《结构与土木工程前沿(英文)》 2016年 第10卷 第1期   页码 30-43 doi: 10.1007/s11709-016-0318-1

摘要: Existing test methods to determine moisture sensitivity in hot-mix asphalt (HMA) mixtures are time consuming and inconsistent. This research focused on wheel tracking devices to evaluate moisture sensitivity. The Asphalt Pavement Analyzer (APA) and the Hamburg Wheel Tracking Device (HWTD) were used for this research. Compacted cylindrical samples were fabricated using a Superpave Gyratory compactor. This study selected two most commonly used mixtures, SM-12.5A with PG 64-22 binder in overlay projects and SM-19A mixtures with PG 64-22 binder for major modification projects at Kansas Department of Transportation. Test results show that APA tests could induce stripping in most samples without any anti-stripping agent, which could be identified visually. However, APA results did not indicate any stripping inflection point while the HWTD results showed stripping inflection points, which are important to identify stripping potential of mixtures. The APA results show that wet tests are severe at lower temperatures. The HWTD results show improvement in the performance using anti-stripping agents at later stage. The HWTD test is more effective as a rapid test method in case of determining moisture sensitivity. Laboratory results from this study should be verified and correlated with field performance.

关键词: hot-mix asphalt     moisture sensitivity     rutting     wheel tracking test    

标题 作者 时间 类型 操作

Real drive cycles analysis by ordered power methodology applied to fuel consumption, CO

Pol Masclans Abelló, Vicente Medina Iglesias, M. Antonia de los Santos López, Jesús Álvarez-Flórez

期刊论文

WEIS wheel speed real-time measuring method for VOSM

Mengyao PAN, Guixiong LIU, Xiaobin HONG, Tusheng LIN,

期刊论文

Time-domain and frequency-domain approaches to identification of bridge flutter derivatives

Zhengqing CHEN

期刊论文

Simulation and analysis of grinding wheel based on Gaussian mixture model

Yulun CHI, Haolin LI

期刊论文

Fatigue and impact analysis and multi-objective optimization design of Mg/Al assembled wheel considering

期刊论文

Lightening structure optimization on turbine wheel of vehicular turbocharger

ZHAO Junsheng, MA Chaochen, HU Liaoping

期刊论文

月球车叶片伸缩式步行轮的力学分析和性能优化

杨璐, 蔡博文, 张荣辉, 李克宁, 张子贤, 雷洁浩, 陈百超, 王荣本

期刊论文

Numerical simulation and experimental research on the wheel brush sampling process of an asteroid sampler

期刊论文

Entity and relation extraction with rule-guided dictionary as domain knowledge

期刊论文

泰州大桥钢桥面铺装轮载谱研究

李洪涛,潘友强,张志祥

期刊论文

Multidisciplinary co-design optimization of structural and control parameters for bucket wheel reclaimer

Yongliang YUAN, Liye LV, Shuo WANG, Xueguan SONG

期刊论文

Effect of cavity defect on the triaxial mechanical properties of high-performance concrete

Yanbin ZHANG; Zhe WANG; Mingyu FENG

期刊论文

Damage identification in connections of moment frames using time domain responses and an optimization

期刊论文

Heat transfer coefficient of wheel rim of large capacity steam turbines

SHI Jinyuan, DENG Zhicheng, YANG Yu, JUN Ganwen

期刊论文

Wheel tracking methods to evaluate moisture sensitivity of hot-mix asphalt mixtures

Jie HAN,Harihar Shiwakoti

期刊论文