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Pijush Samui, Jagan J
《结构与土木工程前沿(英文)》 2013年 第7卷 第2期 页码 133-136 doi: 10.1007/s11709-013-0202-1
关键词: unsaturated soil effective stress parameter Gaussian process regression (GPR) artificial neural network (ANN) variance
The formation mechanism and the influence factor of residual stress in machining
null
《机械工程前沿(英文)》 2014年 第9卷 第3期 页码 265-269 doi: 10.1007/s11465-014-0311-0
Residual stresses generated in cutting process have important influences on workpiece performance. The paper presents a method of theoretical analysis in order to explicate the formation mechanism of residual stresses in cutting. An important conclusion is drawn that the accumulated plastic strain is the main factor which determines the nature and the magnitude of surface residual stresses in the workpiece. On the basis of the analytical model for residual stress, a series of simulations for residual stress prediction during cutting AISI 1045 steel are implemented in order to obtain the influences of cutting speed, depth of cut and tool edge radius on surface residual stress in the workpiece. And these influences are explained from the perspective of formation mechanism of residual stress in cutting. The conclusions have good applicability and can be used to guide the parameters selection in actual production.
关键词: residual stress analytical model strain plastic cutting parameter
Stress-strain relationship with soil structural parameter of collapse loess
SHAO Shengjun, YU Qinggao, LONG Jiyong
《结构与土木工程前沿(英文)》 2008年 第2卷 第3期 页码 293-293 doi: 10.1007/s11709-008-0100-0
Experimental study of modal parameter identification in a simulated ambient-excited structure
JI Xiaodong, QIAN Jiaru, XU Longhe
《结构与土木工程前沿(英文)》 2007年 第1卷 第3期 页码 281-285 doi: 10.1007/s11709-007-0036-9
关键词: eigensystem realization eigen-sensitivity analysis realization algorithm vibration effective
《结构与土木工程前沿(英文)》 2023年 第17卷 第3期 页码 429-447 doi: 10.1007/s11709-022-0913-2
关键词: coral aggregate concrete stress−strain curves lateral effective stress peak stress axial−lateral curves damage-constitutive model.
杨志强,高谦,陈得信,郭慧高
《中国工程科学》 2014年 第16卷 第8期 页码 38-44
金川镍矿是我国最大的硫化铜镍矿,以地应力高、矿体厚大和矿岩不稳固著称国内外采矿界。该矿体开采难度之大、充填成本之高备受国内外采矿界关注。近年来,随着矿床开采深度逐年增加已接近千米,采场面积超过1×105 m2,高温、高压和高渗压的“三高”采矿环境日趋显著,不仅提高了采矿成本,而且还给矿山安全高效生产带来巨大压力。本文首先概述金川深部矿床采矿技术条件,然后明确采矿生产面临巷道和采场稳定性控制技术难题,分析采场围岩变形和岩层移动所潜在的灾变失稳风险。最后提出了金川深部矿体安全高效开采亟待攻克的技术难题,为金川深部资源开发能力和综合利用指明了方向。
赵怡彬,邵旭东
《中国工程科学》 2012年 第14卷 第10期 页码 103-112
桥台处伸缩缝问题是长期困扰工程界的难题,它会带来跳车、桥梁局部损坏、伸缩缝装置经常更换等各种问题。为有效解决这一问题,提出了一种适用于大中型桥梁的新型结构体系——单伸缩缝桥梁(单缝桥)。在考虑接线路面裂缝开展的情况下,建立了温度作用下单缝桥的简化计算模型,推导了单缝桥受力、变形的理论公式,用Fortran90编制程序,进行计算。以一座总长280 m的单缝梁桥为例,温度降低20 ℃时,接线路面钢筋最大应力为148 MPa,最大裂缝宽度为0.185 mm,符合规范要求;台后结构对主梁产生的附加应力仅为0.105 MPa,影响很小。通过对影响单缝桥性能的因素:支座类型、配筋率、接线路面长度、摩擦系数、土体刚度、桥长、温差等进行分析,绘制图表,得到以下主要结论:温降时,接线路面受拉,混凝土开裂,是较不利的状况;30 m长的接线路面可以满足结构受力和变形的需要;选择摩擦系数较小的支座和减少接线路面与垫层的摩擦力可以减少结构内力,在接线路面与垫层间推荐加铺土工格栅。
《机械工程前沿(英文)》 2022年 第17卷 第4期 doi: 10.1007/s11465-022-0703-5
关键词: laser beam welding parameter optimization metamodel multi-objective
null
《医学前沿(英文)》 2012年 第6卷 第3期 页码 288-295 doi: 10.1007/s11684-012-0208-4
Tramadol is a potent analgesic. However, the analgesia efficacy of tramadol, particularly its minimum effective dose (MED), is not clear. The aim of this study is to find MED of tramadol for postoperative analgesia in infants. The continual reassessment method (CRM) was performed to find MED. Infants undergoing surgeries were included in the 3 phases of this series. In each phase, 24 participants were allocated a different tramadol dose. Pain intensity was measured by face, legs, activity, cry, consolability (FLACC) measurement at 3-hour intervals. Tramadol was considered ineffective if the FLACC score was higher than 4 in 10 at anytime. In phase 1, seven dose levels were used within the range 0.1–0.4 mg?kg-1·h-1. Phase 1 was insufficient to identify the MED, and we increased the dose to 0.4–0.8 mg?kg-1·h-1 in phase 2. Phase 2 was insufficient to identify the MED. In phase 3, local anesthetic wound infiltration was introduced, and the tramadol dose levels tested were the same as in phase 1. The successful analgesia probability of tramadol 0.4 mg?kg-1?h-1 was 82.1% (95% CI, 0.742–0.925) in phase 1. In phase 2, it was 84.7% (95% CI, 0.789–0.991) with the dose 0.8 mg?kg-1?h-1. Phase 1 and phase 2 were insufficient to identify the MED. In phase 3, the successful analgesia probability for dose 0.35 mg?kg-1?h-1was 96.7% (95% CI, 0.853–0.997).We have demonstrated that tramadol provides insufficient analgesia for surgeries considered to cause moderate-to-severe postoperative pain in infants if used as the sole analgesic, and that local anesthetic wound infiltration enhances the efficacy of tramadol.
关键词: tramadol minimum effective dose postoperative analgesia infants continual reassessment method
Developing effective tumor vaccines: basis, challenges and perspectives
XU Qingwen, CHEN Weifeng
《医学前沿(英文)》 2007年 第1卷 第1期 页码 11-19 doi: 10.1007/s11684-007-0003-9
关键词: development conventional identification elucidation Successful immunotherapy
王文川,程春田,邱林,杨斌斌
《中国工程科学》 2010年 第12卷 第3期 页码 100-107
应用新安江模型进行水文模拟时,由于模型本身的不足及参数多、信息量少等原因,会出现率定的最优参数组不唯一、不稳定等问题。考虑到以往的参数优选,都只得出一个参数组,不能反映出其不确定性状况。提出应用基于马尔可夫链蒙特卡罗(MCMC)理论的SCEM-UA算法,通过双牌流域以1 h为时段间隔的36场典型洪水数据对新安江模型参数进行优选和不确定性评估。结果表明,该算法能很好地推出新安江模型参数的后验概率分布;率定和检验结果分析也表明,应用SCEM-UA算法对新安江模型进行优选和不确定评估是有效和可行的。
王靖涛
《中国工程科学》 2007年 第9卷 第11期 页码 11-15
将岩土塑性体应变与剪应变的相互作用原理拓展到了非饱和土领域。除了塑性体应变与剪应变的相互作用外,在非饱和土中出现了两类新的相互作用,吸力-塑性体应变和孔隙气压力-塑性体应变。吸力具有二重性质,其对塑性体应变作用包括两个相反的方面。基于吸力性质,阐明了非饱和土的一些独特的性质,诸如有效应力参数的物理涵义,吸力对体积变化和前期固结压力的影响和湿陷机理等。另外,应用拓展的塑性体应变与剪应变相互作用原理,从理论上证明了非饱和土的临界状态线是存在的和唯一的,以及它与应力历史无关。
关键词: 塑性体应变与剪应变的相互作用原理 非饱和土 基质吸力 有效应力原理
1000 MW ultra-supercritical turbine steam parameter optimization
FENG Weizhong
《能源前沿(英文)》 2008年 第2卷 第2期 页码 187-193 doi: 10.1007/s11708-008-0030-5
Structural parameter design method for a fast-steering mirror based on a closed-loop bandwidth
Guozhen CHEN, Pinkuan LIU, Han DING
《机械工程前沿(英文)》 2020年 第15卷 第1期 页码 55-65 doi: 10.1007/s11465-019-0545-y
关键词: fast-steering mirror structural parameter PI controller bandwidth notch filter
Energy efficient cutting parameter optimization
Xingzheng CHEN, Congbo LI, Ying TANG, Li LI, Hongcheng LI
《机械工程前沿(英文)》 2021年 第16卷 第2期 页码 221-248 doi: 10.1007/s11465-020-0627-x
关键词: energy efficiency cutting parameter optimization machining process
标题 作者 时间 类型 操作
Determination of effective stress parameter of unsaturated soils: A Gaussian process regression approach
Pijush Samui, Jagan J
期刊论文
Stress-strain relationship with soil structural parameter of collapse loess
SHAO Shengjun, YU Qinggao, LONG Jiyong
期刊论文
Experimental study of modal parameter identification in a simulated ambient-excited structure
JI Xiaodong, QIAN Jiaru, XU Longhe
期刊论文
Damage-constitutive model for seawater coral concrete using different stirrup confinements subjected to axial loading
期刊论文
Processing parameter optimization of fiber laser beam welding using an ensemble of metamodels and MOABC
期刊论文
Estimation of the minimum effective dose of tramadol for postoperative analgesia in infants using the
null
期刊论文
Developing effective tumor vaccines: basis, challenges and perspectives
XU Qingwen, CHEN Weifeng
期刊论文
Structural parameter design method for a fast-steering mirror based on a closed-loop bandwidth
Guozhen CHEN, Pinkuan LIU, Han DING
期刊论文