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Reliability-based robust design optimization of vehicle components, Part I: Theory

Yimin ZHANG

《机械工程前沿（英文）》 2015年 第10卷 第2期   页码 138-144 doi: 10.1007/s11465-015-0333-2

摘要：

The reliability-based design optimization, the reliability sensitivity analysis and robust design method are employed to present a practical and effective approach for reliability-based robust design optimization of vehicle components. A procedure for reliability-based robust design optimization of vehicle components is proposed. Application of the method is illustrated by reliability-based robust design optimization of axle and spring. Numerical results have shown that the proposed method can be trusted to perform reliability-based robust design optimization of vehicle components.

关键词： vehicle components     reliability-based design optimization     reliability-based sensitivity analysis     multi-objective optimization     robust design    

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Reliability-based robust design optimization of vehicle components, Part II: Case studies

Yimin ZHANG

《机械工程前沿（英文）》 2015年 第10卷 第2期   页码 145-153 doi: 10.1007/s11465-015-0334-1

摘要：

The reliability-based optimization, the reliability-based sensitivity analysis and robust design method are employed to propose an effective approach for reliability-based robust design optimization of vehicle components in Part I. Applications of the method are further discussed for reliability-based robust optimization of vehicle components in this paper. Examples of axles,torsion bar, coil and composite springs are illustrated for numerical investigations. Results have shown the proposed method is an efficient method for reliability-based robust design optimization of vehicle components.

关键词： vehicle axles and springs     reliability-based design optimization     reliability-based sensitivity analysis     multi-objective optimization     robust design    

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Emission components characteristics of a bi-fuel vehicle at idling condition

Sameh M. METWALLEY, Shawki A. ABOUEL-SEOUD, Abdelfattah M. FARAHAT

《能源前沿（英文）》 2011年 第5卷 第3期   页码 322-329 doi: 10.1007/s11708-011-0158-6

摘要： Natural gas (NG) represents today a promising alternative to conventional fuels for road vehicles propulsion, since it is characterized by a relatively low cost, better geopolitical distribution than oil, and lower environmental impact. This explains the current spreading of compressed natural gas (CNG) fuelled spark ignition (SI) engine, above all in the bi-fuel version, which is able to run either with gasoline or with NG. However, the aim of the present investigation is to evaluate the emission characteristics at idling condition. The vehicle engine was converted to bi-fueling system from a gasoline engine, and operated separately either with gasoline or CNG. Two different fuel injection systems (i.e., multi-point injection (MPI)-sequential and closed-loop venturi-continuous) are used, and their influences on the formation of emissions at different operating conditions are examined. A detailed comparative analysis of the engine exhaust emissions using gasoline and CNG is made. The results indicate that the CNG shows low air index and lower emissions of carbon monoxide (CO), carbon dioxide (CO ), and total hydrocarbon (THC) compared to gasoline.

关键词： road vehicle engine     fuel injection systems     carbon monoxide (CO)     carbon dioxide (CO2)     total hydrocarbon (THC)     vehicle idle conditions     air index    

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Experimental study on influence of operating parameters on tar components from corn straw gasification

Shuai GUO, Xiao WEI, Deyong CHE, Hongpeng LIU, Baizhong SUN

《能源前沿（英文）》 2021年 第15卷 第2期   页码 374-383 doi: 10.1007/s11708-020-0710-3

摘要： Gasification is a promising approach for converting solid fuel sources, including renewable ones like biomass, for use. The main problem in biomass gasification is the formation of condensable tars, including polycyclic aromatic hydrocarbons (PAHs). This paper investigated the conversion of tar components during corn straw gasification. It analyzed collected tar components using a gas chromatograph-mass spectrograph (GC-MS). Experimental results indicate that, with increasing temperature from 700°C to 900°C, the concentrations of benzene, indene, phenanthrene, naphthalene, acenaphthylene, fluorene, and pyrene increased whereas those of toluene, phenol, 1-methylnaphthalene, and 2-methylnaphthalene decreased. As the equivalence ratio (ER) increased from 0.21 to 0.34, the concentrations of indene and phenanthrene increased from 0.148% and 0.087% to 0.232% and 0.223%, respectively. Further, the phenol content increased as ER increased from 0.21 to 0.26 and then decreased as the ER increased further to 0.34. Other parameters like the steam/biomass (S/B) ratio and catalyst also played a critical role in tar reduction. This paper demonstrates the conversion of some tar components and elucidates their chemical properties during gasification.

关键词： gasification     tar components     operating parameters    

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Topological reorganization and functional alteration of distinct genomic components in gallbladder cancer

《医学前沿（英文）》 doi: 10.1007/s11684-023-1008-8

摘要： Altered three-dimensional architecture of chromatin influences various genomic regulators and subsequent gene expression in human cancer. However, knowledge of the topological rearrangement of genomic hierarchical layers in cancer is largely limited. Here, by taking advantage of in situ Hi-C, RNA-sequencing, and chromatin immunoprecipitation sequencing (ChIP-seq), we investigated structural reorganization and functional changes in chromosomal compartments, topologically associated domains (TADs), and CCCTC binding factor (CTCF)-mediated loops in gallbladder cancer (GBC) tissues and cell lines. We observed that the chromosomal compartment A/B switch was correlated with CTCF binding levels and gene expression changes. Increased inter-TAD interactions with weaker TAD boundaries were identified in cancer cell lines relative to normal controls. Furthermore, the chromatin short loops and cancer unique loops associated with chromatin remodeling and epithelial–mesenchymal transition activation were enriched in cancer compared with their control counterparts. Cancer-specific enhancer–promoter loops, which contain multiple transcription factor binding motifs, acted as a central element to regulate aberrant gene expression. Depletion of individual enhancers in each loop anchor that connects with promoters led to the inhibition of their corresponding gene expressions. Collectively, our data offer the landscape of hierarchical layers of cancer genome and functional alterations that contribute to the development of GBC.

关键词： 3D genome     cancer     TADs     loop     gene regulation    

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Characteristics of chemical components in PM

Jianwu SHI,Xiang DING,Yue ZHOU,Ran YOU,Lu HUANG,Jiming HAO,Feng XIANG,Jian YANG,Ze SHI,Xinyu HAN,Ping NING

《环境科学与工程前沿（英文）》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0841-2

摘要： The mass concentrations of PM were studied at a plateau city. Seasonal and spatial variation of chemical components in PM were analyzed. Primary emissions were the main contributors of PM . A sampling campaign including summer, autumn and winter of 2014 and spring of 2015 was accomplished to obtain the characteristic of chemical components in PM at three sites of Kunming, a plateau city in South-west China. Nine kinds of water-soluble inorganic ions (WSI), organic and element carbon (OC and EC) in PM were analyzed by ion chromatography and thermal optical reflectance method, respectively. Results showed that the average concentrations of total WSI, OC and EC were 22.85±10.95 μg·m , 17.83±9.57 μg·m and 5.11±4.29 μg·m , respectively. They totally accounted for 53.0% of PM . Secondary organic and inorganic aerosols (SOA and SIA) were also assessed by the minimum ratio of OC/EC, nitrogen and sulfur oxidation ratios. The annual average concentrations of SOA and SIA totally accounted for 28.3% of the PM concentration. The low proportion suggested the primary emission was the main source of PM in Kunming. However, secondary pollution in the plateau city should also not be ignorable, due to the appropriate temperature and strong solar radiation, which can promote the atmospheric photochemical reactions.

关键词： PM2.5     Plateau city     Organic carbon     Element carbon     Inorganic ions     Secondary components    

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陶瓷喷墨打印增材制造技术 Review

Brian Derby

《工程（英文）》 2015年 第1卷 第1期   页码 113-123 doi: 10.15302/J-ENG-2015014

摘要：

陶瓷喷墨打印是一种基于微滴累加的成形技术，典型的微滴体积为10~100 pL。实现微滴累加成形的关键是开发稳定的陶瓷墨水，合适的墨水需要满足由雷诺数和韦伯数定义的流变特性参数空间。在微滴累加成形过程中，微滴首先与成形面碰撞变形并消耗动能，然后在毛细管力作用下铺展并达到平衡状态。已经可以确定的是打印过程中微滴相互作用并形成一维线性特征的机理，但是对二维和三维结构成形机理的认识还处于较低水平，成形二维面的稳定性低于成形一维线性结构。多数情况下，墨水通过蒸发固化，微滴碰撞基体所产生的“咖啡环”缺陷需要通过固化工艺加以控制。已经有大量文献报道了使用喷墨打印技术成形各种类型小型陶瓷零件的成功案例。作为一种未来的制造技术，陶瓷喷墨打印技术有广阔的应用前景。本综述的目的是探索陶瓷喷墨打印技术未来潜在的研究领域，加强对这种制造方法的理解。

关键词： 增材制造     3D打印     喷墨打印     陶瓷零件    

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Connected morphable components-based multiscale topology optimization

Jiadong DENG, Claus B. W. PEDERSEN, Wei CHEN

《机械工程前沿（英文）》 2019年 第14卷 第2期   页码 129-140 doi: 10.1007/s11465-019-0532-3

摘要： The advances of manufacturing techniques, such as additive manufacturing, have provided unprecedented opportunities for producing multiscale structures with intricate latticed/cellular material microstructures to meet the increasing demands for parts with customized functionalities. However, there are still difficulties for the state-of-the-art multiscale topology optimization (TO) methods to achieve manufacturable multiscale designs with cellular materials, partially due to the disconnectivity issue when tiling material microstructures. This paper attempts to address the disconnectivity issue by extending component-based TO methodology to multiscale structural design. An effective linkage scheme to guarantee smooth transitions between neighboring material microstructures (unit cells) is devised and investigated. Associated with the advantages of components-based TO, the number of design variables is greatly reduced in multiscale TO design. Homogenization is employed to calculate the effective material properties of the porous materials and to correlate the macro/structural scale with the micro/material scale. Sensitivities of the objective function with respect to the geometrical parameters of each component in each material microstructure have been derived using the adjoint method. Numerical examples demonstrate that multiscale structures with well-connected material microstructures or graded/layered material microstructures are realized.

关键词： multiscale topology optimization     morphable component     material microstructure     homogenization    

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Forecast method for used number of parts and components based on complex network

LIU Fu-yun, QI Guo-ning, YANG Qing-hai

《机械工程前沿（英文）》 2006年 第1卷 第4期   页码 479-484 doi: 10.1007/s11465-006-0064-5

摘要： Applying directed complex network to model the main structure of a product family, according to in-degree bi-logarithmic coordinate distribution curve and distribution rule of nodes of the network, in-degree evolving rule of nodes of the network is presented and analytic expression of in-degree probability density of nodes is derived. Through the analysis of the relation between existing kinds of components and existing product numbers, an expression of the relation between kinds of components and product numbers is derived. A forecast method for the increment of component numbers and parts based on the increment of products is presented. As an example, the component numbers of an industrial steam turbine product family is forecasted, forecast result verified and forecast error analyzed.

关键词： complex network     industrial     component     analytic expression     forecast    

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CNC programming system for complex components based on KBE within integrated environment of CAD/CAPP/

Shengwen ZHANG, Guicheng WANG, Liang ZHANG, Xifeng FANG

《机械工程前沿（英文）》 2009年 第4卷 第1期   页码 97-102 doi: 10.1007/s11465-009-0007-z

摘要： To promote the research and development of modern digital and intelligent manufacturing technology and overcome shortcomings of computerized numerical control(CNC) programming for complex components, an innovative idea has been proposed to introduce knowledge based engineering (KBE) into the field of CNC programming within the integrated environment of CAD/CAPP/CAM. This paper constructs the architecture of CNC programming based on KBE within CAD/CAPP/CAM and explores the key technology of applying KBE to CNC programming — knowledge representation, knowledge acquisition, knowledge reasoning, and generalized knowledge base system of CNC programming. The integration of the CAD/CAM system and the CAPP system of enterprises has been achieved by taking the powerful CAD/CAM system of UG NX as a platform. The prototype system of CNC programming for complex components based on KBE within CAD/CAPP/CAM has been developed by means of UG/Open,VC++6.0, and SQL Sever 2000. Finally, a frame example, one of the complex components of a marine diesel, is presented, and the academic production and the intelligence of the system are verified.

关键词： NC programming     CAD/CAPP/CAM     KBE    

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长征三号系列运载火箭

龙乐豪

《中国工程科学》 1999年 第1卷 第1期   页码 11-18

摘要：

论述了长征三号系列运载火箭诞生的背景、设计思路、总体技术方案、应用发射结果及其在技术与研制工作方面的特点，展望了其发展前景，指出该系列运载火箭是我国目前性能先进的大型主力商业应用发射火箭群体。

关键词： 航天     大型运载火箭     发射服务     长征三号系列    

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油料中功能性成分的研究开发与油脂工程技术的发展

张根旺

《中国工程科学》 2000年 第2卷 第3期   页码 82-86

摘要：

植物油料是植物油脂与植物蛋白的主要来源。油脂中所含的某些脂肪酸及某种结构的甘油酯具有特殊的生理功能，近几年来，这方面的研究开发取得了重要进展。国内外的油脂工业主要是利用油料生产各种食用油脂，其次是获取植物蛋白制品。实际上，在油脂精炼及植物蛋白制取过程中产生的许多所谓“废料”，长期以来未得到充分利用。近些年发现，在“废料”中很多伴随油脂的类脂物及伴随植物蛋白的植物化学品，具有独特的生理效能，因而这些高附加值的功能性成分的开发利用受到高度重视。由于油料中的功能性成分的特殊性，现有的油料加工工艺与装备不能适应其分离提取的要求，由此推动着油脂工程技术的发展和生物技术在功能性结构脂开发上的应用。

关键词： 油料     功能性成分     技术发展    

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Hybrid flexural components: Testing pre-stressed steel and GFRP bars together as reinforcement for flexural

Mohammed FARUQI, Oved I. MATA, Francisco AGUINIGA

《结构与土木工程前沿（英文）》 2018年 第12卷 第3期   页码 352-360 doi: 10.1007/s11709-017-0453-3

摘要：

Concrete members historically have used either pre-stressed steel or steel bars. In recent years there has been an increased interest in the use of fiber reinforced polymer (FRP) materials. However, the flexure behavior of a hybrid system reinforced by the combination of pre-stressed steel and glass fiber reinforced (GFRP) is still relatively unknown. The purpose of this work is to study this. Two slabs of 100 and 150-millimeter thickness, with a span of 2.1 m reinforced with both pre-stressing steel and GFRP were constructed and tested to failure using ACI 318-11 and ACI 440.1R-15. The concrete had strength of 31 MPa and the slabs were respectively reinforced with 5#4 bars and 3#5 bars. Each slab had 37.41 mm2 prestressing wire with a failure stress of 1722.5 MPa. The experimental flexural strength and deflection of slabs were compared with their respective sizes theoretical slabs. The theoretical slabs were either reinforced with pre-stressed steel or GFRP rebars, or a hybrid system. It was found that the hybrid system produces better results.

关键词： Partial pre-stressing     composite structures     GFRP bars    

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Particle formation of hydroxyapatite precursor containing two components in a spray pyrolysis process

W. Widiyastuti, Adhi Setiawan, Sugeng Winardi, Tantular Nurtono, Heru Setyawan

《化学科学与工程前沿（英文）》 2014年 第8卷 第1期   页码 104-113 doi: 10.1007/s11705-014-1406-1

摘要： The particle formation mechanism of hydroxyapatite precursor containing two components, Ca(OOCCH ) and (NH ) HPO with a ratio of Ca/P= 1.67, in a spray pyrolysis process has been studied by computational fluid dynamics (CFD) simulation on the transfer of heat and mass from droplets to the surrounding media. The focus included the evaporation of the solvent in the droplets, a second evaporation due to crust formation, the decomposition reaction of each component of the precursor, and a solid-state reaction that included the kinetic parameters of the precursor regarding its two components that formed the hydroxyapatite product. The rate of evaporation and the reacted fraction of the precursor both increased with temperature. The predicted average size of the hydroxyapatite particles agreed well with the experimental results. Therefore, the selected models were also suitable for predicting the average size of particles that contain two components in the precursor solution.

关键词： droplet     hydroxyapatite particle     CFD     tubular furnace     spray pyrolysis    

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Development of oxide based diffusion barrier coatings for CFC components applied in modern furnaces

Kirsten BOBZIN, Lidong ZHAO, Thomas SCHLAEFER, Thomas WARDA

《机械工程前沿（英文）》 2011年 第6卷 第4期   页码 392-396 doi: 10.1007/s11465-011-0241-z

摘要：

Carbon fibre reinforced carbon (CFC) materials show a high potential for usage in furnaces as sample carriers for example, which is due to their excellent thermal stability compared to steel carriers. Only their tendency to react with different metals at high temperatures by C-diffusion is a disadvantage, which can be solved by application of diffusion barriers. In order to enable the utilization of CFC-carriers for e.g. brazing furnaces, within the frame of this study thermally sprayed diffusion barrier coatings were developed. Coatings of mullite and ZrO2-7%βY2O3 (YSZ) were prepared by air plasma spraying (APS). The coatings were investigated in terms of their microstructure and thermal shock behaviour. In order to prove the suitability of the coatings for the application in brazing furnaces, the wettability of the coating surfaces by a Ni-based brazing alloy was investigated. The results showed that both mullite and YSZ could be deposited on CFC substrates with a bond coat of W or SiC. Both coatings exhibited good thermal shock behaviour and an excellent non-wetting behaviour against the used Ni-based braze alloy.

关键词： diffusion barrier coatings     carbon fibre reinforced carbon (CFC)     plasma spraying     microstructure     furnace    

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标题 作者 时间 类型 操作

Reliability-based robust design optimization of vehicle components, Part I: Theory

Yimin ZHANG

期刊论文

Reliability-based robust design optimization of vehicle components, Part II: Case studies

Yimin ZHANG

期刊论文

Emission components characteristics of a bi-fuel vehicle at idling condition

Sameh M. METWALLEY, Shawki A. ABOUEL-SEOUD, Abdelfattah M. FARAHAT

期刊论文

Experimental study on influence of operating parameters on tar components from corn straw gasification

Shuai GUO, Xiao WEI, Deyong CHE, Hongpeng LIU, Baizhong SUN

期刊论文

Topological reorganization and functional alteration of distinct genomic components in gallbladder cancer

期刊论文

Characteristics of chemical components in PM

Jianwu SHI,Xiang DING,Yue ZHOU,Ran YOU,Lu HUANG,Jiming HAO,Feng XIANG,Jian YANG,Ze SHI,Xinyu HAN,Ping NING

期刊论文

陶瓷喷墨打印增材制造技术

Brian Derby

期刊论文

Connected morphable components-based multiscale topology optimization

Jiadong DENG, Claus B. W. PEDERSEN, Wei CHEN

期刊论文

Forecast method for used number of parts and components based on complex network

LIU Fu-yun, QI Guo-ning, YANG Qing-hai

期刊论文

CNC programming system for complex components based on KBE within integrated environment of CAD/CAPP/

Shengwen ZHANG, Guicheng WANG, Liang ZHANG, Xifeng FANG

期刊论文

长征三号系列运载火箭

龙乐豪

期刊论文

油料中功能性成分的研究开发与油脂工程技术的发展

张根旺

期刊论文

Hybrid flexural components: Testing pre-stressed steel and GFRP bars together as reinforcement for flexural

Mohammed FARUQI, Oved I. MATA, Francisco AGUINIGA

期刊论文

Particle formation of hydroxyapatite precursor containing two components in a spray pyrolysis process

W. Widiyastuti, Adhi Setiawan, Sugeng Winardi, Tantular Nurtono, Heru Setyawan

期刊论文

Development of oxide based diffusion barrier coatings for CFC components applied in modern furnaces

Kirsten BOBZIN, Lidong ZHAO, Thomas SCHLAEFER, Thomas WARDA

期刊论文