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 218

会议视频 8

年份

2023 19

2022 20

2021 17

2020 18

2019 15

2018 19

2017 10

2016 8

2015 11

2014 3

2013 13

2012 4

2011 9

2010 3

2009 8

2008 8

2007 10

2006 6

2005 3

2004 3

展开︾

关键词

机器学习 4

材料设计 4

冶金 3

材料 3

颠覆性技术 3

增材制造 2

新材料 2

智能制造 2

材料科学 2

碳中和 2

2019全球工程前沿 1

2035 1

3D 打印 1

4D打印 1

FRP 聚合物 1

MCDB 1

SUF钢板 1

中国 1

中子源 1

展开︾

检索范围：

排序：展示方式：

Effects of sheet thickness and material on the mechanical properties of flat clinched joint

Chao CHEN, Huiyang ZHANG, Shengdun ZHAO, Xiaoqiang REN

《机械工程前沿（英文）》 2021年第16卷第2期页码 410-419 doi: 10.1007/s11465-020-0618-y

摘要： The flat clinching process is attracting a growing attention in the joining field of lightweight materials because it avoids the geometric protrusion that appears in the conventional clinching process. In this paper, the effects of sheet thickness and material on the mechanical properties of the clinched joint were studied. Al1060 and Al2024 sheets with 2 mm thickness were employed to develop the clinched joint by using different material configurations, and Al1060 sheets with 2.5- and 1.5-mm thicknesses were used to produce the clinched joint by using different thickness configurations. The clinched joints using various sheet configurations were sectioned, and dimensional analysis was conducted. Cross-tensile and shearing tests were carried out to analyze the mechanical properties of the clinched joint, including tensile strength, shearing strength, and absorbed energy. In addition, the failure modes of the clinched joints were discussed. Results indicated that the clinched joint with a stiff top sheet had increased static strength regardless of the test type. The clinched joint with a thick top sheet demonstrated lower static strength than the joint with a thick bottom sheet in the cross-tensile test. However, this result was reversed in the shearing tests. The flat clinching process has a great potential in joining dissimilar and various thickness materials.

关键词： clinched joint flat clinching process thickness configuration material configuration mechanical property

HTML PDF 收藏

Application of cable-supported spatial grid in dry coal shed

XING Haidong, HAO Jiping, XU Guobin

《结构与土木工程前沿（英文）》 2008年第2卷第1期页码 26-29 doi: 10.1007/s11709-008-0008-8

摘要： This paper presented a new structural style cable-supported spatial grid, which was applied in large span dry coal sheds. The influence of configuration of cable on the force of cable and beam, the ratio of beam force to cable force and the deflection of span was investigated, and a rational configuration of cable was obtained. The results show that the cable-supported spatial grid can maximize the use of material strength, and have the advantages of low usage of steel, large span and sufficient headroom.

关键词： dry material strength low rational configuration influence

HTML PDF 收藏

Effects of green roof damping and configuration on structural seismic response

《结构与土木工程前沿（英文）》页码 1133-1144 doi: 10.1007/s11709-023-0959-9

摘要： Sustainable structures are critical for addressing global climate change. Hence, their structural resilience or ability to recover from natural events must be considered comprehensively. Green roofs are a widely used sustainable feature that improve the environment while providing excellent occupant amenity. To expand their usage, their inherent damping and layout sensitivity to seismic performance are investigated in this study. The soil of a green roof can serve as a damper to dissipate the energy generated by earthquakes or other dynamic events. Results of preliminary analysis show that a green roof soil can increase localized damping by 2.5% under both dry and saturated conditions. Based on these findings, nonlinear time-history analyses are conducted on a three-story building in SAP2000 to monitor the structural behavior with and without a green roof. The increased damping in the green roof soil is beneficial to the structural performance, i.e., it reduces the building displacement and acceleration by 10% and 12%, respectively. Additionally, certain configurations are more effective and beneficial to the structural response than others, which suggests the possibility of design optimization. Based on the findings of this study, new methods of modeling and considering green roofs in structural design are established.

关键词： green infrastructure green roof structural resilience seismic design

HTML PDF 收藏

Effect of cutterhead configuration on tunnel face stability during shield machine maintenance outages

《结构与土木工程前沿（英文）》 2023年第17卷第4期页码 522-532 doi: 10.1007/s11709-023-0930-9

摘要： Owing to long-distance advancement or obstacles, shield tunneling machines are typically shut down for maintenance. Engineering safety during maintenance outages is determined by the stability of the tunnel face. Pressure maintenance openings are typically used under complicated hydrogeological conditions. The tunnel face is supported by a medium at the bottom of the excavation chamber and compressed air at the top. Owing to the high risk of face failure, the necessity of support pressure when cutterhead support is implemented and a method for determining the value of compressed air pressure using different support ratios must to be determined. In this study, a non-fully chamber supported rotational failure model considering cutterhead support is developed based on the upper-bound theorem of limit analysis. Numerical simulation is conducted to verify the accuracy of the proposed model. The results indicate that appropriately increasing the specific gravity of the supporting medium can reduce the risk of collapse. The required compressed air pressure increases significantly as the support ratio decreases. Disregarding the supporting effect of the cutterhead will result in a tunnel face with underestimated stability. To satisfy the requirement of chamber openings at atmospheric pressure, the stratum reinforcement strength and range at the shield end are provided based on different cutterhead aperture ratios.

关键词： tunnel face stability cutterhead configuration aperture ratio pressure gradient support ratio

HTML PDF 收藏

Optimizing the configuration of a clearwell by integrating pilot and full-scale tracer testing

LIU Wenjun, DU Zhipeng, JIN Junwei

《环境科学与工程前沿（英文）》 2007年第1卷第3期页码 270-275 doi: 10.1007/s11783-007-0045-x

摘要： In this paper, the main factors impacting the plug flow pattern of a clearwell were investigated by integrating pilot-scale, full-scale clearwell tracer testing and computational fluid dynamics (CFD) simulation. It was found that pilot tracer testing, full-scale tracer testing and CFD simulation all demonstrated that the correlation between the ratio of / and can be approximately expressed by: / = 0.189 4ln()-0.049 4. This study confirmed that the installation of baffles within clearwells is an efficient way to optimize their configuration. In addition, the inlet velocity has a minimal contribution to the ratio of /. However, the ratio of turning channel width to channel width () significantly contributes to the ratio of/. The optimal ratio of is 0.8–1.2 for maintaining better plug flow pattern. The number of turning channels is one of the main factors that impact the ratio of /. When increasing the number of turning channels, a lower ratio of / is obtained.

HTML PDF 收藏

Tracing the impact of stack configuration on interface resistances in reverse electrodialysis by in situ

《环境科学与工程前沿（英文）》 2022年第16卷第4期 doi: 10.1007/s11783-021-1480-9

摘要：

• RED performance and stack resistance were studied by EIS and LSV.

关键词： Reverse electrodialysis Electrochemical impedance spectroscopy Concentration polarization Spacer shadow effect

HTML PDF 收藏

Passive convergence-permeable reactive barrier (PC-PRB): An effective configuration to enhance hydraulic

《环境科学与工程前沿（英文）》 2022年第16卷第12期 doi: 10.1007/s11783-022-1591-y

摘要：

● A novel PRB configuration based on passive convergent flow effect was proposed.

关键词： Passive convergence-permeable reactive barrier (PC-PRB) Permeable reactive barrier configuration Numerical simulation Hydraulic performance evaluation Sensitivity analysis

HTML PDF 收藏

运动规划的高效配置空间构建与优化 Article

潘佳, Dinesh Manocha

《工程（英文）》 2015年第1卷第1期页码 46-57 doi: 10.15302/J-ENG-2015009

摘要：

配置空间是算法机器人学领域使用较为广泛的一种基本概念。机器人学、计算机辅助设计与相关领域的诸多应用都可归类为配置空间方面的计算问题。本文将对近期与配置空间相关的两项重大挑战的解决方案成果进行探讨：①如何高效计算高维配置空间的近似表达；②如何在高维配置空间内高效执行几何学接近度与运动规划查询。基于机器学习与几何学近似技术，笔者在此提出几种新型配置空间构建算法。上述算法对多个配置样本进行碰撞查询。得出的碰撞查询结果将用来计算配置空间的近似表达，可快速聚合至准确的配置空间；同时还提出了基于并行图形处理器（GPU）的算法，以便加速配置空间优化与搜索计算的性能情况。笔者特别设计出了基于GPU的并行k最近邻算法与并行碰撞检测算法，并使用这些算法来加快运动规划。

关键词：配置空间运动规划图形处理器（GPU）并行算法

HTML PDF 收藏

马尔可夫网络排队模型在电梯配置中的应用

宗群,程义菊,宋军远

《中国工程科学》 2003年第5卷第10期页码 69-72

摘要：

利用马尔可夫网络排队理论建立了电梯交通模型，在此基础上对各服务站的电梯配置交通进行计算，得到电梯的配置参数。通过与传统的电梯配置方法相比较，显示出明显的优越性，也表明了利用马尔可夫网络排队模型进行电梯配置的有效性和可行性。

关键词：马尔可夫网络排队理论电梯交通模型优化电梯配置

HTML PDF 收藏

深圳城市供水系统产权结构重组模式及评价

肖文,欧阳芳锐,王先甲

《中国工程科学》 2004年第6卷第7期页码 48-52

摘要：

提出了城市供水系统产权结构重组的两种基本模式，运用制度经济学和管理学理论，提出产权结构模式评价的指标与方法，分析了这两种产权结构模式的特性和在这两种模式下不同利益主体的行为与利益关系的变化特点及优缺点，并提出了缓解劣势的手段与方法。

关键词：城市供水产权结构产权重组产权模式评价

HTML PDF 收藏

Flutter control effect and mechanism of central-slotting for long-span bridges

YANG Yongxin, GE Yaojun, XIANG Haifan

《结构与土木工程前沿（英文）》 2007年第1卷第3期页码 298-304 doi: 10.1007/s11709-007-0039-6

摘要： The flutter control effect and mechanism of central-slotting, which have gradually been adopted in the design and construction of long-span bridges as an effective flutter controlling measure, were investigated with theoretical analysis and wind tunnel test. Five basic girder cross-sections representing five typical aerodynamic configurations were selected and central-slotted with two different slot widths. Then, a series of sectional model tests and theoretical analyses based on the two-dimensional three-degrees-of-freedom coupling flutter analysis method (2 dimension-3 degrees of freedom method, 2d-3DOF method) were carried out to investigate the aerodynamic performance, flutter mechanism and flutter modality of the five basic sections and their corresponding central-slotted sections. The results show that central-slotting can not always improve the aerodynamic stability of bridge structure. The control effect of central-slotting depends on the aerodynamic configuration of the original girder section and the corresponding central-slotting width. If the original section is inappropriate or the slot width is unsuitable, central-slotting will even deteriorate the structural flutter performance. Theoretical investigations indicated that the differences in flutter control effects come from the different formation and evolution of aerodynamic damping, and flutter modality especially the participation level of heaving motion also has a significant influence on the control effect of central-slotting.

关键词： aerodynamic configuration aerodynamic performance flutter mechanism aerodynamic stability theoretical analysis

HTML PDF 收藏

Liquid metal material genome: Initiation of a new research track towards discovery of advanced energy

Lei WANG, Jing LIU

《能源前沿（英文）》 2013年第7卷第3期页码 317-332 doi: 10.1007/s11708-013-0271-9

摘要： As the basis of modern industry, the roles materials play are becoming increasingly vital in this day and age. With many superior physical properties over conventional fluids, the low melting point liquid metal material, especially room-temperature liquid metal, is recently found to be uniquely useful in a wide variety of emerging areas from energy, electronics to medical sciences. However, with the coming enormous utilization of such materials, serious issues also arise which urgently need to be addressed. A biggest concern to impede the large scale application of room-temperature liquid metal technologies is that there is currently a strong shortage of the materials and species available to meet the tough requirements such as cost, melting point, electrical and thermal conductivity, etc. Inspired by the Material Genome Initiative as issued in 2011 by the United States of America, a more specific and focused project initiative was proposed in this paper—the liquid metal material genome aimed to discover advanced new functional alloys with low melting point so as to fulfill various increasing needs. The basic schemes and road map for this new research program, which is expected to have a worldwide significance, were outlined. The theoretical strategies and experimental methods in the research and development of liquid metal material genome were introduced. Particularly, the calculation of phase diagram (CALPHAD) approach as a highly effective way for material design was discussed. Further, the first-principles (FP) calculation was suggested to combine with the statistical thermodynamics to calculate the thermodynamic functions so as to enrich the CALPHAD database of liquid metals. When the experimental data are too scarce to perform a regular treatment, the combination of FP calculation, cluster variation method (CVM) or molecular dynamics (MD), and CALPHAD, referred to as the mixed FP-CVM-CALPHAD method can be a promising way to solve the problem. Except for the theoretical strategies, several parallel processing experimental methods were also analyzed, which can help improve the efficiency of finding new liquid metal materials and reducing the cost. The liquid metal material genome proposal as initiated in this paper will accelerate the process of finding and utilization of new functional materials.

关键词： liquid metal material genome energy material material discovery advanced material room-temperature liquid alloy thermodynamics phase diagram

HTML PDF 收藏

Robust topology optimization of multi-material lattice structures under material and load uncertainties

Yu-Chin CHAN, Kohei SHINTANI, Wei CHEN

《机械工程前沿（英文）》 2019年第14卷第2期页码 141-152 doi: 10.1007/s11465-019-0531-4

摘要： Enabled by advancements in multi-material additive manufacturing, lightweight lattice structures consisting of networks of periodic unit cells have gained popularity due to their extraordinary performance and wide array of functions. This work proposes a density-based robust topology optimization method for meso- or macro-scale multi-material lattice structures under any combination of material and load uncertainties. The method utilizes a new generalized material interpolation scheme for an arbitrary number of materials, and employs univariate dimension reduction and Gauss-type quadrature to quantify and propagate uncertainty. By formulating the objective function as a weighted sum of the mean and standard deviation of compliance, the tradeoff between optimality and robustness can be studied and controlled. Examples of a cantilever beam lattice structure under various material and load uncertainty cases exhibit the efficiency and flexibility of the approach. The accuracy of univariate dimension reduction is validated by comparing the results to the Monte Carlo approach.

关键词： robust topology optimization lattice structures multi-material material uncertainty load uncertainty univariate dimension reduction

HTML PDF 收藏

State-of-art review of the optimization methods to design the configuration of hybrid renewable energy

Maurizio FACCIO, Mauro GAMBERI, Marco BORTOLINI, Mojtaba NEDAEI

《能源前沿（英文）》 2018年第12卷第4期页码 591-622 doi: 10.1007/s11708-018-0567-x

摘要： The current research aims to present an inclusive review of latest research works performed with the aim of improving the efficiency of the hybrid renewable energy systems (HRESs) by employing diverse ranges of the optimization techniques, which aid the designers to achieve the minimum expected total cost, while satisfying the power demand and the reliability. For this purpose, a detailed analysis of the different classification drivers considering the design factors such as the optimization goals, utilized optimization methods, grid type as well as the investigated technology has been conducted. Initial results have indicated that of all optimization goals, load demand parameters including loss of power supply probability (LPSP) and loss of load probability (LLP), cost, sizing (configuration), energy production, and environmental emissions are the most frequent design variables which have been cited the most. Another result of this paper indicates that almost 70% of the research projects have been dedicated toward the optimization of the off-grid applications of the HRESs. Furthermore, it has been demonstrated that, integration of the PV, wind and battery is the most frequent configuration. In the next stage of the paper, a review concerning the sizing methods has also been carried out to outline the most common techniques which are used to configure the components of the HRESs. In this regard, an analysis covering the optimized indicators such as the cost drivers, energy index parameters, load indicators, battery’s state of charge, PV generator area, design parameters such as the LPSP, and the wind power generation to load ratio, has also been performed.

关键词： hybrid renewable energy systems (HRESs) design and optimization environmental pollutions PV array wind turbines (WTs) inverter diesel generator (DG)

HTML PDF 收藏

工程材料研究中科学问题的思考

于翘

《中国工程科学》 1999年第1卷第3期页码 1-4

摘要：

在不少场合下，航天用工程材料处在极端条件下工作，这就对材料提出许多特殊的要求，虽然国内外有一定的研究积累，但对更精确的模型和符合特定材料的损伤的状态方程，有待深一步研究。如高级弹头再入时气动加热和粒子云侵蚀以及两者耦合效应引起弹头防护材料增大后退量的问题；空中垃圾和微流星的高速碰撞对航天器的威胁；特别是核爆和激光武器对材料的损伤和破坏，实质上是辐射引起的热击波层裂破坏，这些都属于超高速碰撞对材料的响应问题。天线罩材料、吸波材料、红外隐身材料、电磁屏蔽材料都是具有不同波长电磁波的电磁功能材料，它们对固体介质的穿透、吸收、反射等会产生响应，不同的电磁功能材料，其宏观性能的物理参量不同，但有几个参量是通用的，如介电常数、磁导率和损耗角正切，搞清这些参量与材料微观结构的关系，可以为材料设计和材料创新提供科学依据。

关键词：天线罩材料吸波材料红外隐身材料电磁兼容材料