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期刊论文 8

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2016 1

2015 1

2010 2

2007 3

2004 1

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基质吸力 2

非饱和土 2

V形坑 1

体积含水量 1

体积应变 1

剪切带 1

剪切应变 1

圆形巷道 1

塑性体应变与剪应变的相互作用原理 1

岩爆 1

扩容角 1

有效应力原理 1

稳定性分析 1

降雨入渗 1

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非饱和土坡危险含水量分析

张士林,王冬梅,李根华

《中国工程科学》 2004年第6卷第5期页码 71-75

摘要：

介绍了由于雨水入渗，使非饱和土坡的含水量发生变化，而含水量正是与基质吸力有着直接的联系；同时通过分析条件水压力和非饱和土的容重与含水量的变化规律，得到基质吸力、饱和度、非饱和土容重与整个土坡的稳定性规律，也就是安全系数与含水量分布的规律。得出当土坡处于危险状况下的含水量分布，即当土坡中的含水量达到危险含水量时，土坡处于危险状态。因此，通过监测土坡的含水量的变化，获得土坡的稳定信息，为生产和安全提供保障。

关键词：非饱和土稳定性分析降雨入渗体积含水量基质吸力

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非饱和土的塑性体应变与剪应变的相互作用原理

王靖涛

《中国工程科学》 2007年第9卷第11期页码 11-15

摘要：

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

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Experimental evaluation and simulation of volumetric shrinkage and warpage on polymeric composite short

Jonnathan D. SANTOS,Jorge I. FAJARDO,Alvaro R. CUJI,Jaime A. GARCÍA,Luis E. GARZÓN,Luis M. LÓPEZ

《机械工程前沿（英文）》 2015年第10卷第3期页码 287-293 doi: 10.1007/s11465-015-0346-x

摘要：

A polymeric natural fiber-reinforced composite is developed by extrusion and injection molding process. The shrinkage and warpage of high-density polyethylene reinforced with short natural fibers of Guadua angustifolia Kunth are analyzed by experimental measurements and computer simulations. Autodesk Moldflow^® and Solid Works^® are employed to simulate both volumetric shrinkage and warpage of injected parts at different configurations: 0 wt.%, 20 wt.%, 30 wt.% and 40 wt.% reinforcing on shrinkage and warpage behavior of polymer composite. Become evident the restrictive effect of reinforcing on the volumetric shrinkage and warpage of injected parts. The results indicate that volumetric shrinkage of natural composite is reduced up to 58% with fiber increasing, whereas the warpage shows a reduction form 79% to 86% with major fiber content. These results suggest that it is a highly beneficial use of natural fibers to improve the assembly properties of polymeric natural fiber-reinforced composites.

关键词： biocomposite natural fiber shrinkage simulation warpage

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Error measurement and assemble error correction of a 3D-step-gauge

MAO Xinyong, LI Bin, SHI Hanmin, LIU Hongqi, LI Xi, LI Peigen

《机械工程前沿（英文）》 2007年第2卷第4期页码 388-393 doi: 10.1007/s11465-007-0067-x

摘要： A new artifact called 3D-step-gauge consisting of a pyramid array and a compound, is proposed to calculate geometrical errors for machine tools. Only one point on each profile of the pyramid in the array is probed, and its center coordinate can be calculated. Then, the intervals of the pyramids can be transfered a length standard to measure errors. Considering the differences in the structural parameters and the location of the pyramids, a volumetric error measurement method of discrete points is presented. Furthermore, the location errors between the calibration state and the measurement state are studied and their influences on the accuracy of the position measurement are investigated on an actual machine tool. The 3D-step-gauge was tested on an actual machine tool and the measurement result shows quick assembly, convenient measurement, and high accuracy.

关键词： volumetric pyramid assembly accuracy calibration

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Optimization of phosphorus removal in uniFed SBR system for domestic wastewater treatment

Xuguang TANG, Shuying WANG, Yongzhen PENG

《环境科学与工程前沿（英文）》 2010年第4卷第4期页码 475-481 doi: 10.1007/s11783-010-0244-8

摘要： The characteristic of phosphorus removal and appropriate change of the traditional operation modes were investigated in UniFed sequencing batch reactor (SBR) laboratory-scale apparatus (40 L), treating actual domestic wastewater with low ratios of C/N (2.57) and C/P (30.18), providing theoretical basis for actual application of wastewater treatment plant. UniFed SBR system with its unique operation mode had the distinct superiority of phosphorus removal. On this occasion, the effect of volumetric exchange ratio (VER) and the method of influent introduction for phosphorus removal were studied. When the carbon source became the limiting factor to phosphorus release, the higher the VER, the lower the phosphorus concentration in the effluent. Three different influent patterns, including one-time filling, four-time filling, and continuous filling with the same quantity of wastewater could increase the release rate of anaerobic phosphorus from 0.082 to 0.143 mg·P·(L·min) . Appropriate change of the traditional operation modes could optimize the efficiency of phosphorus removal. When the feed/ decant time was extended from 2 h to 4 h, the phosphorous removal efficiency increased from 59.93% to 88.45% without any external carbon source. In the mode of alternation of anoxic-aerobic (A/O) condition, phosphorous removal efficiency increased from 55.07% to 72.27% clearly. The carbon source in the influent can be used adequately, and denitrifying phosphorus removal was carried out in anoxic stage 2 (A2). This mode was optimal for the treatment of actual domestic wastewater with low C/N and C/P ratios.

关键词： UniFed sequencing batch reactor (SBR) phosphorus removal volumetric exchange ratio (VER) alternation of anoxic-aerobic (A/O) domestic wastewater

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New method for computer numerical control machine tool calibration: Relay method

LIU Huanlao, SHI Hanming, LI Bin, ZHOU Huichen

《机械工程前沿（英文）》 2007年第2卷第3期页码 301-304 doi: 10.1007/s11465-007-0053-3

摘要： Relay measurement method, which uses the kilogram-meter (KGM) measurement system to identify volumetric errors on the planes of computer numerical control (CNC) machine tools, is verified through experimental tests. During the process, all position errors on the entire plane table are measured by the equipment, which is limited to a small field. All errors are obtained first by measuring the error of the basic position near the original point. On the basis of that positional error, the positional errors far away from the original point are measured. Using this analogy, the error information on the positional points on the entire plane can be obtained. The process outlined above is called the relay method. Test results indicate that the accuracy and repeatability are high, and the method can be used to calibrate geometric errors on the plane of CNC machine tools after backlash errors have been well compensated.

关键词： positional volumetric information process repeatability

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Process improvement in laser hot wire cladding for martensitic stainless steel based on the Taguchi method

Zilin HUANG,Gang WANG,Shaopeng WEI,Changhong LI,Yiming RONG

《机械工程前沿（英文）》 2016年第11卷第3期页码 242-249 doi: 10.1007/s11465-016-0397-7

摘要：

Laser hot wire cladding, with the prominent features of low heat input, high energy efficiency, and high precision, is widely used for remanufacturing metal parts. The cladding process, however, needs to be improved by using a quantitative method. In this work, volumetric defect ratio was proposed as the criterion to describe the integrity of forming quality for cladding layers. Laser deposition experiments with FV520B, one of martensitic stainless steels, were designed by using the Taguchi method. Four process variables, namely, laser power (P), scanning speed (V_s), wire feed rate (V_f), and wire current (I), were optimized based on the analysis of signal-to-noise (S/N) ratio. Metallurgic observation of cladding layer was conducted to compare the forming quality and to validate the analysis method. A stable and continuous process with the optimum parameter combination produced uniform microstructure with minimal defects and cracks, which resulted in a good metallurgical bonding interface.

关键词： process optimization Taguchi method signal-to-noise (S/N) ratio volumetric defect ratio laser hot wire cladding

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扩容角对圆形巷道岩爆过程的影响

王学滨,潘一山,张智慧

《中国工程科学》 2010年第12卷第2期页码 40-46

摘要：

利用FLAC模拟了不同扩容角时圆形巷道的岩爆过程。为了模拟巷道开挖，利用编写的FISH函数删除巷道内部的单元。岩石服从莫尔库仑剪破坏与拉破坏复合的破坏准则，破坏之后呈现应变软化—理想塑性行为。文章的模拟分为3步：首先，将静水压力施加在模型上，直到达到静力平衡状态；然后，利用编写的FISH函数，开挖巷道；最后，计算重新开始，直到达到静力平衡状态。模拟结果表明，随着扩容角的增加，剪切带变宽，岩爆坑变深，破坏单元数目增多，破坏区变大。当扩容角较低时，高剪切应变集中于“狗耳”形岩爆坑位置，剪切带与巷道周边切线之间的夹角较大；当扩容角较高时，高剪切应变集中于巷道周边的一些位置上，剪切带与巷道周边切线之间的夹角较小。该研究结果与Roscoe，Arthur理论相符。

关键词：扩容角圆形巷道岩爆剪切带 V形坑剪切应变体积应变