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Multi-objective optimization of surface texture for the slipperswash plate interface in EHA pumps

《机械工程前沿（英文）》 2022年 第17卷 第4期 doi: 10.1007/s11465-022-0704-4

摘要： Well-designed surface textures can improve the tribological properties and the efficiency of the electro-hydrostatic actuator (EHA) pump under high-speed and high-pressure conditions. This study proposes a multi-objective optimization model to obtain the arbitrarily surface textures design of the slipper/swash plate interface for improving the mechanical and volumetric efficiency of the EHA pump. The model is composed of the lubrication film model, the component dynamic model considering the spinning motion, and the multi-objective optimization model. In this way, the arbitrary-shaped surface texture with the best comprehensive effect in the EHA pump is achieved and its positive effects in the EHA pump prototype are verified. Experimental results show a reduction in wear and an improvement in mechanical and volumetric efficiency by 1.4% and 0.8%, respectively, with the textured swash plate compared with the untextured one.

关键词： electro-hydrostatic actuator     axial piston pump     slipper/swash plate interface     multi-objective optimization     surface texture    

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Laboratory and field evaluation of asphalt pavement surface friction resistance

Zhong WU, Chris ABADIE

《结构与土木工程前沿（英文）》 2018年 第12卷 第3期   页码 372-381 doi: 10.1007/s11709-017-0463-1

摘要：

Pavement surface friction is a significant factor for driving safety and plays a critical role in reducing wet-pavement crashes. However, the current asphalt mixture design procedure does not directly consider friction as a requirement. The objective of this study was to develop a surface friction prediction model that can be used during a wearing course mixture design. To achieve the objective, an experimental study was conducted on the frictional characteristics of typical wearing course mixtures in Louisiana. Twelve wearing course mixtures including dense-graded and open-graded mixes with different combinations of aggregate sources were evaluated in laboratory using an accelerated polishing and testing procedure considering both micro- and macro texture properties. In addition, the surface frictional properties of asphalt mixtures were measured on twenty-two selected asphalt pavement sections using different in situ devices including Dynamic Friction Tester (DFT), Circular Texture Meter (CTM), and Lock-Wheel Skid Trailer (LWST). The results have led to develop a procedure for predicting pavement end-of-life skid resistance based on the aggregate blend polish stone value, gradation parameters, and traffic, which is suited in checking whether the selected aggregates in a wearing course mix design would meet field friction requirements under a certain design traffic polishing.

关键词： friction skid resistance     polishing     PSV     LWST     micro-texture     macro-texture    

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Application of MoS in the space environment: a review

《机械工程前沿（英文）》 2023年 第18卷 第3期 doi: 10.1007/s11465-023-0755-1

摘要： A considerable portion of space mechanism failures are related to space tribological problems. Cold welding in high vacuum; surface erosion and collision damage caused by various radiations, high temperature oxidation under atomic oxygen (AO) bombardment; and thermal stress caused by temperature alternation all alter the physical, chemical, and friction properties of materials. In particular, the space vibration caused by alternating temperatures and microgravity environments can alter the motion of the contact body, further affecting its friction properties. Improving the friction properties of contact surfaces in the space environment is an important way to extend the service life of spacecraft. Traditional lubricants can no longer meet the lubrication requirements of the space environment. This study describes the characteristics of the space environment and the applications of solid lubricants. The friction properties of MoS2, a solid lubricant widely used in space, are discussed. The synergistic lubrication of MoS2 with surface textures or metals is presented. Advances in research on the friction properties of collision sliding contacts in the space environment are reviewed. The combination of MoS2 and soft metals with surface textures is introduced to reduce the effects of vibration environments on the friction properties of moving parts in space mechanisms. Finally, the challenges and future research interests of MoS2 films in space tribology are presented.

关键词： MoS2     soft metal     space environment     surface texture     synergistic effect     vibration    

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Study on micro-texture and skid resistance of aggregate during polishing

Zhenyu QIAN, Lingjian MENG

《结构与土木工程前沿（英文）》 2017年 第11卷 第3期   页码 346-352 doi: 10.1007/s11709-017-0409-7

摘要： The skid resistance performance of pavement is closely related to the micro-texture of pavement aggregate, while there is very few research on the relationship between micro-texture and the skid resistance. In this paper, the optical microscope is used to acquire the surface morphology of three types of aggregates including basalt, limestone and red sandstone respectively, where a total of 12 indicators are developed based on the surface texture information. The polishing effect on aggregate is simulated by Wehner/Schulze (W/S) device, during the polishing procedure, the skid resistance are measured by British Pendulum Tester (BPT). Based on the results of independent T-test and the polishing resistance analysis, it shows that the surface texture of basalt is significantly different between limestone and red sandstone. Three indicators including the average roughness ( ), the kurtosis of the surface ( ) and the mean summit curvature ( ) are selected to describe the characteristics of aggregate micro-texture based on the correlation analysis. The contribution of micro-texture to the skid resistance can be described with the secondary polynomial regression model by these indicators.

关键词： skid resistance of pavement     micro-texture     aggregates     polishing test    

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Multi-resolution texture synthesis from turntable image sequences

Xuedong WANG, Xiaojun WU, Xiaorong ZHANG

《机械工程前沿（英文）》 2012年 第7卷 第1期   页码 72-80 doi: 10.1007/s11465-012-0305-8

摘要：

Texture synthesis and texture mapping are important technologies for rendering realistic three-dimensional scene. It has been widely used in virtual reality, urban modeling, 3D animation, gaming and other areas. In this paper, we propose a fast method to construct high quality texture map for multi-resolution texture synthesis from turntable image sequences. Given a 3D mesh model, we first get the projection relationship between 3D mesh and image sequences. We then use image sequences to construct a texture triangle for each 3D triangle mesh and get a global rectangular texture map for the whole mesh. Another approach to construct a texture map is using Stretch-minimizing mesh parameterization. Finally, we map the texture to mesh model to verify the quality of these two methods. The high performance of this method has been demonstrated in many real object models.

关键词： texture synthesis     multi-resolution     texture map     texture mapping    

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A multi-probe micro-fabrication apparatus based on the friction-induced fabrication method

Zhijiang WU, Chenfei SONG, Jian GUO, Bingjun YU, Linmao QIAN

《机械工程前沿（英文）》 2013年 第8卷 第4期   页码 333-339 doi: 10.1007/s11465-013-0276-4

摘要：

A novel multi-probe micro-fabrication apparatus was developed based on the friction-induced fabrication method. The main parts of the apparatus include actuating device, loading system, and control system. With a motorized linear stage, the maximum fabrication area of 50 mm × 50 mm can be achieved, and the maximum sliding speed of probes can be as high as 10 mm/s. Through locating steel micro balls into indents array, the preparation of multi-probe array can be realized by a simple and low-cost way. The cantilever was designed as a structure of deformable parallelogram with two beams, by which the fabrication force can be precisely controlled. Combining the friction-induced scanning with selective etching in KOH solution, various micro-patterns were fabricated on Si(100) surface without any masks or exposure. As a low-cost and high efficiency fabrication device, the multi-probe micro-fabrication apparatus may encourage the development of friction-induced fabrication method and shed new light on the texture engineering.

关键词： friction-induced fabrication     silicon     surface texture     friction     multi-probe    

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Effect of steady shear on multi-axial texture of symmetric diblock copolymers

XU Hui, LIU Honglai, HU Ying

《化学科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 26-34 doi: 10.1007/s11705-007-0006-8

摘要： The effect of steady shear on multi-axial texture of symmetric diblock copolymer was investigated by using dynamic density functional theory. Through modifying the periodic boundary condition, the parallel-transverse biaxial texture and perpendicular-parallel-transverse triaxial texture have been observed. In the formation of the multi-axial texture, there are two critical velocities μ and µ, at which the transition between the perpendicular and the parallel lamellar morphology, and the transition between the parallel and the transverse lamellar morphology occur, respectively. The two critical velocities increase as the interaction parameter increases, but they almost remain constant at different shear rates. Furthermore, the rotation from the transverse lamellae to the parallel lamellae induced by the shear strain, and the increase of lamellar spacings of the three lamellae after removing the shear, have also been observed by the time evolution of the morphologies. These phenomena are consistent with experimental work.
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The effect of texture and irrigation on the soil moisture vertical-temporal variability in an urban artificial

Xiaofeng ZHANG,Xu ZHANG,Guanghe LI

《环境科学与工程前沿（英文）》 2015年 第9卷 第2期   页码 269-278 doi: 10.1007/s11783-014-0672-y

摘要： Soil moisture variability in natural landscapes has been widely studied; however, less attention has been paid to its variability in the urban landscapes with respect to the possible influence of texture stratification and irrigation management. Therefore, a case study was carried out in the Beijing Olympic Forest Park to continuously monitor the soil in three typical profiles from 26 April to 11 November 2010. The texture stratification significantly affected the vertical distribution of moisture in the non-irrigated profile where moisture was mostly below field capacity. In the profile where irrigation was sufficient to maintain moisture above field capacity, gravity flow led to increased moisture with depth and thus eliminated the influence of texture. In the non-irrigated sites, the upper layer (above 80 cm) exhibited long-term moisture persistence with the time scale approximating the average rainfall interval. However, a coarse-textured layer weakened the influence of rainfall, and a fine-textured layer weakened the influence of evapotranspiration, both of which resulted in random noise-like moisture series in the deeper layers. At the irrigated site, frequent irrigation neutralized the influence of evapotranspiration in the upper layer (above 60 cm) and overshadowed the influence of rainfall in the deeper layer. As a result, the moisture level in the upper layer also behaved as a random noise-like series; whereas due to deep transpiration, the moisture of the deep layer had a persistence time-scale longer than a month, consistent with characteristic time-scales found for deep transpiration.

关键词： moisture vertical distribution     moisture temporal variation     texture stratification     irrigation     meteorological forcing     urban landscape    

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High-quality industrial n-type silicon wafers with an efficiency of over 23% for Si heterojunction solar cells

Fanying MENG,Jinning LIU,Leilei SHEN,Jianhua SHI,Anjun HAN,Liping ZHANG,Yucheng LIU,Jian YU,Junkai ZHANG,Rui ZHOU,Zhengxin LIU

《能源前沿（英文）》 2017年 第11卷 第1期   页码 78-84 doi: 10.1007/s11708-016-0435-5

摘要： n-type CZ-Si wafers featuring longer minority carrier lifetime and higher tolerance of certain metal contamination can offer one of the best Si-based solar cells. In this study, Si heterojuction (SHJ) solar cells which was fabricated with different wafers in the top, middle and tail positions of the ingot, exhibited a stable high efficiency of>22% in spite of the various profiles of the resistivity and lifetime, which demonstrated the high material utilization of n-type ingot. In addition, for effectively converting the sunlight into electrical power, the pyramid size, pyramid density and roughness of surface of the Cz-Si wafer were investigated by scanning electron microscope (SEM) and transmission electron microscope (TEM). Furthermore, the dependence of SHJ solar cell open-circuit voltage on the surface topography was discussed, which indicated that the uniformity of surface pyramid helps to improve the open-circuit voltage and conversion efficiency. Moreover, the simulation revealed that the highest efficiency of the SHJ solar cell could be achieved by the wafer with a thickness of 100 µm. Fortunately, over 23% of the conversion efficiency of the SHJ solar cell with a wafer thickness of 100 µm was obtained based on the systematic optimization of cell fabrication process in the pilot production line. Evidently, the large availability of both n-type ingot and thinner wafer strongly supported the lower cost fabrication of high efficiency SHJ solar cell.

关键词： n-type Cz-Si     thinner wafer     surface texture     high efficiency     SHJ solar cell    

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基于纹理及小波分析的车牌定位方法

黄卫,路小波,余彦翔,凌小静

《中国工程科学》 2004年 第6卷 第3期   页码 19-24

摘要：

提出了一种基于纹理和小波分析的车牌定位方法。针对图像背景复杂，且车牌所占比例较小的特点，提出了一种确定基元分类阈值的二值化方法；根据车牌字符分布规律，提出了二值纹理基元分析方法，提取车牌候选区域；基于小波分析提取车牌区域竖笔画特征，采用隶属度定量表征车牌竖笔画特征、位置特征及形状特征，给出综合这些特征、从候选区域提取车牌区域的方法。测试结果表明，该方法正确定位率超过96%

关键词： 纹理     小波分析     基元     车牌定位    

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腌制工艺对大菱鲆质构及理化性质的影响

王甜甜,李振兴,林洪,郭晓华

《中国工程科学》 2014年 第16卷 第9期   页码 64-68

摘要：

本文通过分析腌制大菱鲆质构及理化指标的变化，研究食盐浓度、腌制时间和腌制方式等对腌制大菱鲆品质的影响。结果表明：食盐浓度和腌制时间对腌制大菱鲆咀嚼度影响显著（P<0.05），对硬度、弹性和胶黏性无显著影响；腌制方式对腌制品的硬度、弹性和胶黏性影响显著（P<0.05），对咀嚼度无显著影响。在腌制过程中，食盐浓度每增加2 %，酸价降低1.03 mg/g，过氧化值平均降低0.1 g/100 g；腌制时间越长，酸价和过氧化值均有所升高；对感官评价来说，腌制时间有比较显著的影响（P<0.05）。由此可知，腌制工艺对大菱鲆产品的品质有显著的影响，本文通过分析各参数的影响，为进一步优化大菱鲆腌制工艺提供基础数据。

关键词： 腌制工艺     大菱鲆     质构     理化性质     感官评价    

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Mechanical properties of rock materials with related to mineralogical characteristics and grain size through experimental investigation: a comprehensive review

Wenjuan SUN, Linbing WANG, Yaqiong WANG

《结构与土木工程前沿（英文）》 2017年 第11卷 第3期   页码 322-328 doi: 10.1007/s11709-017-0387-9

摘要： Mechanical properties of rock materials are related to textural characteristics. The relationships between mechanical properties and textural characteristics have been extensively investigated for differently types of rocks through experimental tests. Based on the experimental test data, single- and multiple- variant regression analyses are conducted among mechanical properties and textural characteristics. Textural characteristics of rock materials are influenced by the following factors: mineral composition, size, shape, and spatial distribution of mineral grains, porosity, and inherent microcracks. This study focuses on the first two: mineral composition and grain size. ? This study comprehensively summarizes the regression equations between mechanical properties and mineral content and the regression equations between mechanical properties and grain size. Further research directions are suggested at the end of this study.

关键词： Mechanical properties     rock material     texture     mineral characteristics    

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Electromagnetic induction mapping at varied soil moisture reveals field-scale soil textural patterns and gravel lenses

Hiruy ABDU, David A. ROBINSON, Janis BOETTINGER, Scott B. JONES

《农业科学与工程前沿（英文）》 2017年 第4卷 第2期   页码 135-145 doi: 10.15302/J-FASE-2017143

摘要： Knowledge of the spatial distribution of soil textural properties is important for determining soil moisture storage and soil hydraulic transport properties. Capturing field heterogeneity without exhaustive sampling and costly sample analysis is difficult. Our objective was to employ electromagnetic induction (EMI) mapping in low apparent electrical conductivity (EC ) soils at varying soil water contents to capture time invariant properties such as soil texture. Georeferenced EC measurements were taken using a ground conductivity meter on six different days where volumetric water content ( ) varied from 0.11 to 0.23. The 50 m × 50 m field included a subsurface gravelly patch in an otherwise homogeneous silt-loam alluvial soil. Ordinary block kriging predicted EC at unsampled areas to produce 1-m resolution maps. Temporal stability analysis was used to divide the field into three distinct EC regions. Subsequent ground-truthing confirmed the lowest conductivity region correlated with coarse textured soil parent materials associated with a former high-energy alluvial depositional area. Combining maps using temporal stability analysis gives the clearest image of the textural difference. These maps could be informative for modeling, experimental design, sensor placement and targeted zone management strategies in soil science, ecology, hydrology, and agricultural applications.

关键词： soil electrical conductivity     soil texture mapping     temporal stability analysis    

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Cell surface protein engineering for high-performance whole-cell catalysts

Hajime Nakatani,Katsutoshi Hori

《化学科学与工程前沿（英文）》 2017年 第11卷 第1期   页码 46-57 doi: 10.1007/s11705-017-1609-3

摘要： Cell surface protein engineering facilitated by accumulation of information on genome and protein structure involves heterologous production and modification of cell surface proteins using genetic engineering, and is important for the development of high-performance whole-cell catalysts. In this field, cell surface display is a major technology by exposing target proteins, such as enzymes, on the cell surface using a carrier protein. The target proteins are fused to the carrier proteins that transport and tether them to the cell surface, as well as to a secretion signal. This paper reviews cell surface display systems for prokaryotic and eukaryotic cells from the perspective of carrier proteins, which determine the number of displayed molecules, and the localization, size, and direction ( or terminal anchoring) of the passengers. We also discuss advanced methods for displaying multiple enzymes and a new method for the immobilization of whole-cell catalysts using adhesive surface proteins.

关键词： cell surface engineering     surface display     whole-cell catalysts     bioprocess    

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An Exploration of Surface Integrity Remanufacturing for Aeroengine Components

Qiao Xiang,Yong He,Ting-hong Hou

《工程管理前沿（英文）》 2016年 第3卷 第2期   页码 107-114 doi: 10.15302/J-FEM-2016025

摘要： Surface integrity is the major factor impacting on the operation quality, service life and reliability of the aeroengine components. The surface integrity of aeroengine component is damaged by the failures such as crack, deformation, oxidation, corrosion, erosion, and microstructural degeneration. It adopts advanced remanufacturing technologies to restore or improve the surface integrity and regenerate these high value parts. This paper firstly puts forward the concept, namely surface integrity remanufacturing for aeroengine components, and its connotation. The key remanufacturing technologies have been developed to repair the components with surface damages. Ultimately, some application examples of surface integrity remanufacturing technologies as well as their effects in aeroengine maintenance are introduced. The discarded components have been reused and their service lives have been extended and their reliability has been increased by implementing surface integrity remanufacturing. It has realized “The Repaired Components Outpacing the New Ones”, material saving, energy saving, and emission reduction.

关键词： aeroengine component     surface integrity     remanufacturing     surface integrity remanufacturing    

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标题 作者 时间 类型 操作

Multi-objective optimization of surface texture for the slipperswash plate interface in EHA pumps

期刊论文

Laboratory and field evaluation of asphalt pavement surface friction resistance

Zhong WU, Chris ABADIE

期刊论文

Application of MoS in the space environment: a review

期刊论文

Study on micro-texture and skid resistance of aggregate during polishing

Zhenyu QIAN, Lingjian MENG

期刊论文

Multi-resolution texture synthesis from turntable image sequences

Xuedong WANG, Xiaojun WU, Xiaorong ZHANG

期刊论文

A multi-probe micro-fabrication apparatus based on the friction-induced fabrication method

Zhijiang WU, Chenfei SONG, Jian GUO, Bingjun YU, Linmao QIAN

期刊论文

Effect of steady shear on multi-axial texture of symmetric diblock copolymers

XU Hui, LIU Honglai, HU Ying

期刊论文

The effect of texture and irrigation on the soil moisture vertical-temporal variability in an urban artificial

Xiaofeng ZHANG,Xu ZHANG,Guanghe LI

期刊论文

High-quality industrial n-type silicon wafers with an efficiency of over 23% for Si heterojunction solar cells

Fanying MENG,Jinning LIU,Leilei SHEN,Jianhua SHI,Anjun HAN,Liping ZHANG,Yucheng LIU,Jian YU,Junkai ZHANG,Rui ZHOU,Zhengxin LIU

期刊论文

基于纹理及小波分析的车牌定位方法

黄卫,路小波,余彦翔,凌小静

期刊论文

腌制工艺对大菱鲆质构及理化性质的影响

王甜甜,李振兴,林洪,郭晓华

期刊论文

Mechanical properties of rock materials with related to mineralogical characteristics and grain size through experimental investigation: a comprehensive review

Wenjuan SUN, Linbing WANG, Yaqiong WANG

期刊论文

Electromagnetic induction mapping at varied soil moisture reveals field-scale soil textural patterns and gravel lenses

Hiruy ABDU, David A. ROBINSON, Janis BOETTINGER, Scott B. JONES

期刊论文

Cell surface protein engineering for high-performance whole-cell catalysts

Hajime Nakatani,Katsutoshi Hori

期刊论文

An Exploration of Surface Integrity Remanufacturing for Aeroengine Components

Qiao Xiang,Yong He,Ting-hong Hou

期刊论文