467 results on '"Lu, Wen-Feng"'
Search Results
202. Business information modeling for process integration in the mold making industry
- Author
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Ni, Qianfu, primary, Lu, Wen Feng, additional, Yarlagadda, Prasad K.D.V., additional, and Ming, Xinguo, additional
- Published
- 2007
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203. A framework for integrated manufacturing and product service system: integrating service operations into product life cycle
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Lee, Hui Mien, primary, Lu, Wen Feng, additional, Song, Bin, additional, Shen, Zhiqi, additional, Yang, Zhonghua, additional, and Gay, Robert Kheng Leng, additional
- Published
- 2007
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204. A two-level parser for patent claim parsing.
- Author
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Wang, Jingjing, Lu, Wen Feng, and Loh, Han Tong
- Subjects
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PATENT claim interpretation , *SYNTAX (Grammar) , *DATA mining , *PARSING (Computer grammar) , *PRODUCT design - Abstract
Patent claim parsing can contribute in many patent-related applications, such as patent search, information extraction, machine translation and summarization. However, patent claim parsing is difficult due to the special structure of patent claims. To overcome this difficulty, the challenges facing the patent claim parsing were first investigated and the peculiarities of claim syntax that obstruct dependency parsing were highlighted. To handle these peculiarities, this study proposes a new two-level parser, in which a conventional parser is imbedded. A patent claim is pre-processed in order to remove peculiarities before passed to the conventional parser. The process is based on a new dependency-based syntax called Independent Claim Segment Dependency Syntax (ICSDS). This two-lever parser has demonstrated promising improvement for patent claim parsing on both effectiveness and efficiency over the conventional parser. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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205. Semantic Representations for Configurable Enterprise Systems
- Author
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Ni, Qianfu, primary, Yarlagadda, Prasad K. D. V., additional, and Lu, Wen Feng, additional
- Published
- 2006
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206. A PDM-based Framework for Design to Manufacturing in Mold Making Industry - A Case Study of Business Process Integration
- Author
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Ni, Qianfu, primary, Lu, Wen Feng, additional, and Yarlagadda, Prasad K. D. V., additional
- Published
- 2006
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207. Modeling of an Integrated Process Planning System
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Ni, Qianfu, primary, Yarlagadda, Prasad K. D. V., additional, and Lu, Wen Feng, additional
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- 2006
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208. Analysis of Time-to-Failure Data with Weibull Model in Product Life Cycle Management.
- Author
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Zhai, Lian-Yin, Lu, Wen-Feng, Liu, Ying, Li, Xiang, and Vachtsevanos, George
- Published
- 2013
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209. Methodology for an Integrated Life Cycle Approach to Product End-of-Life Planning.
- Author
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Low, Jonathan Sze Choong, Lu, Wen-Feng, Lee, Hui Mien, and Song, Bin
- Published
- 2013
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210. Systematic Product Inspection and Verification to Improve Returned Product Recovery.
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Ng, Yen Ting, Lu, Wen-Feng, Lee, Hui Mien, and Song, Bin
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- 2013
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211. Towards a Unified In-Process Geometrical Model for Multiple Machining and Layered Manufacturing
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Liu, Peiling, primary, Zhu, Cheng-Feng, additional, Song, Bin, additional, Lu, Wen Feng, additional, Lu, YiQiang, additional, and Ding, Xiaoming, additional
- Published
- 2005
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212. Product Structure Modelling for the Made-to-Order Environment
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Ni, Qianfu, primary, Yarlaggada, Prasad K. D. V., additional, and Lu, Wen Feng, additional
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- 2005
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213. The New Challenge for Color Management in Digital Printing
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Zhang, Allan N. S., primary, Nee, Andrew Y. C., additional, Youcef-Toumi, Kamal, additional, Lu, Wen Feng, additional, Ma, Bin, additional, and Lan, Winson, additional
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- 2005
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214. An Intelligent Color Quality Control Method for Digital Printing
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Zhang, Allan Nengsheng, primary, Nee, Andrew Y C, additional, Youcef-Toumi, Kamal, additional, Lu, Wen Feng, additional, Lan, Winson, additional, and Ma, Bin, additional
- Published
- 2004
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215. ICC Profile Verification for Digital Printing
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Zhang, Allan Nengsheng, primary, Nee, Andrew Y C, additional, Youcef-Toumi, Kamal, additional, Lu, Wen Feng, additional, Lan, Winson, additional, and Ma, Bin, additional
- Published
- 2004
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216. Methodology for modelling the eco-efficiency of closed-loop product life cycles.
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Low, Jonathan Sze Choong, Lu, Wen Feng, Lee, Hui Mien, and Song, Bin
- Abstract
There are potential eco-efficiency benefits from ‘closing the loop’ in product life cycles. However, its implementation is not always straightforward especially for manufacturers of complex products such as electronic devices. They need to know how, where and when to close the loop in order to achieve the desired improvement in eco-efficiency. To help them do this, we propose a methodology that is specially developed for modelling the integrated systems of closed-loop product life cycles. This methodology revolves around a technique whereby product life cycles are deconstructed based on their product structures. Through this technique, life cycle processes and attributes associated with each component can modelled separately before being combined to form the integrated life cycle model of the whole product that includes the mainstream production stage, EoL stage, and any interdependence between the two stages as a result of closing the product life cycle loop. An LED dive torchlight is used as an example to illustrate the application of this methodology and demonstrate its capability as a tool for manufacturers to model their supply chain from an integrated life cycle perspective. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
217. Improving e-waste recovery with energy efficiency information of products.
- Author
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Ng, Yen Ting, Lee, Hui Mien, Lu, Wen Feng, and Low Sze Choong, Jonathan
- Abstract
Energy efficiency is one of the critical parameters to determine e-waste recovery feasibility in order to improve resource efficiency and sustainable consumption and production. Thus, a proper assessment of product efficiency is necessary to achieve optimal end-of-life (EoL) product recovery strategy. This paper proposes a generic method to assess the product efficiency based on energy efficiency analysis and reliability analysis. The assessment leads to identifying residual value of EoL product before any recovery decision is made. A near perfect efficient product or component could be reused, on the other hand, recovery option for inefficient part would be decided based on its efficiency, residual value and reliability. With the accurate EoL product status assessment, e-waste recovery could be enhanced by retaining the materials and energy embedded in EoL product. The proposed e-waste recovery methodology is prime important to industry. It aids product designer, manufacturer and policy maker work toward a better environmental decision making for resource efficiency and a sustainable economic growth. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
218. A Knowledge-Supported System for Engineering Change Impact Analysis
- Author
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Ma, Sha, primary, Song, Bin, additional, Lu, Wen Feng, additional, and Zhu, Cheng Feng, additional
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- 2003
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219. An Integrated Manufacturing and Product Services System (IMPSS) Concept for Sustainable Product Development.
- Author
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Lee Hui Mien, Lu Wen Feng, Gay, R., and Kheng Leng
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- 2005
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220. Survival Benefits From Adjuvant Lenvatinib for Patients With Hepatocellular Carcinoma and Microvascular Invasion After Curative Hepatectomy.
- Author
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Dai, Mu-Gen, Liu, Si-Yu, Lu, Wen-Feng, Liang, Lei, and Ye, Bin
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THERAPEUTIC use of antineoplastic agents , *STATISTICS , *CONFIDENCE intervals , *MULTIVARIATE analysis , *CANCER relapse , *SURVIVAL analysis (Biometry) , *KAPLAN-Meier estimator , *DESCRIPTIVE statistics , *HEPATOCELLULAR carcinoma , *HEPATECTOMY , *OVERALL survival - Abstract
Background: The long-term prognosis of patients with hepatocellular carcinoma (HCC) after surgery remains far from satisfactory, especially in patients with microvascular invasion (MVI). This study aimed to evaluate the potential survival benefit from adjuvant lenvatinib for patients with HCC and MVI. Methods: Patients with HCC after curative hepatectomy were reviewed. All patients were divided into 2 groups according to adjuvant lenvatinib. Propensity score matching (PSM) analysis was used to reduce selection bias and make the results more robust. Survival curves are shown by the Kaplan-Meier (K-M) analysis and compared by the Log-rank test. Univariate and multivariate Cox regression analyses were performed to determine the independent risk factors. Results: Of 179 patients enrolled in this study, 43 (24%) patients received adjuvant lenvatinib. After PSM analysis, 31 pairs of patients were enrolled for further analysis. Survival analysis before and after PSM analysis showed a better prognosis in the adjuvant lenvatinib group (all P <.05). The adverse events associated with oral lenvatinib were acceptable. Multivariate Cox regression analysis showed that adjuvant lenvatinib was an independent protective factor for improving overall survival (OS) (hazard ratio [HR] = 0.455, 95% confidence interval [CI] = 0.249-0.831, P =.001) and recurrence-free survival (RFS) (HR = 0.523, 95% CI = 0.308-0.886, P =.016). Conclusions: Postoperative adjuvant targeted therapy can improve the long-term prognosis of patients with HCC and MVI. Therefore, in clinical practice, oral lenvatinib should be recommended for patients with HCC and MVI to decrease tumor recurrence and improve long-term survival. [ABSTRACT FROM AUTHOR]
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- 2023
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221. Quantification of End-of-life Product Condition to Support Product Recovery Decision.
- Author
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Ng, Yen Ting, Lu, Wen Feng, and Song, Bin
- Abstract
Abstract: This paper proposes concept to decide end-of-life (EoL) product recovery option, followed by methods to quantify product condition. A case study is presented using refrigerator crankshaft to illustrate the implication of product condition on product recovery decision making. The product condition comprises wear-out life of the product, change of dimension and cleanliness level. The advantage from the proposed concept is twofold - firstly, knowledge learned and embedded resources from EoL products able to get back to the product life cycle chain as a closed loop and, secondly, the most favourable EoL product recovery option can be made wisely. With thorough understanding of EoL product condition, it enables original equipment manufacturers (OEMs) to make quick and informed decision. [Copyright &y& Elsevier]
- Published
- 2014
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222. Product Structure-Based Integrated Life Cycle Analysis (PSILA): a technique for cost modelling and analysis of closed-loop production systems.
- Author
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Low, Jonathan Sze Choong, Lu, Wen Feng, and Song, Bin
- Subjects
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PRODUCT life cycle , *LIFE cycle costing , *PRODUCT costing , *CLOSED loop systems , *MANUFACTURING processes , *FLAT panel displays - Abstract
Abstract: As closed-loop production becomes an increasingly viable strategy for product life cycle management, cost modelling and analytical tools for closed-loop production systems will become increasingly important. Existing tools based on life cycle costing (LCC) methods are lacking an integrated life cycle perspective in their approach – a perspective that cannot be overlooked when modelling closed-loop production systems. In this paper, we aim to solve this lack of integrated life cycle approach by proposing the product structure-based integrated life cycle analysis (PSILA) technique. It allows us to streamline the process of modelling a closed-loop production system for a complex product based on its product structure. Through this technique, we developed a cost model of a closed-loop production system for a flat-panel (FPD) monitor case study. In this case study, the results simulated by the cost model show an increase in the economic performance when closed-loop production is adopted for the FPD monitor. Deeper analysis of the results in the case study indicate that in order to improve the economic performance of the closed-loop production system for the FPD monitor, the best strategy is not to merely focus on the reutilisation of materials. Instead, the option to remanufacture the FPD monitor for the secondary market should be explored to maximise the value reclaimed from the monitors in the EoL phase. The case study demonstrates that the cost model developed through the PSILA technique has the ability to function as a tool for analysing the economic performance of closed-loop production systems. More importantly, it has the ability to provide us with strategic insights on the cost feasibility of adopting closed-loop production strategies. [Copyright &y& Elsevier]
- Published
- 2014
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223. A framework for assessing product End-Of-Life performance: reviewing the state of the art and proposing an innovative approach using an End-of-Life Index.
- Author
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Lee, Hui Mien, Lu, Wen Feng, and Song, Bin
- Subjects
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PRODUCT life cycle assessment , *TECHNOLOGICAL innovations , *AUTOMOBILE industry & the environment , *PERFORMANCE evaluation , *KNOWLEDGE gap theory - Abstract
Abstract: Sustainable product development has become an important consideration by many product manufacturers in recent years. Manufacturers are adopting the life cycle approach in the development of products by incorporating the End-of-Life stage considerations at the design stage. To achieve this, however, there is the need to fill up the knowledge gap between the End-of-Life stage and design stage. Tools and methodologies for Design for End-of Life are required to assist designers to design products with better End-of-Life performance. In this paper, a novel Design for End-of-Life methodology is proposed. The methodology captures, represents and analyses the knowledge from the End-of-Life stage into a product End-of-Life Index. The index enables designers to make informed decision on design alternatives for optimal product End-of-Life performance using information from the End-of-Life stage. A case study illustrating the application of this End-of-Life Index on a power tool is subsequently presented. From the discussion, it was shown that the index was able to help to assess the End-of-Life performance of the design and also the changes made subsequently. In essence, this work done here has been demonstrated to be of assistance to designer to adopt Design for End-of-Life. [Copyright &y& Elsevier]
- Published
- 2014
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224. The effects of the density extremum and boundary conditions on the stability of a horizontally confined water layer
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Lu Wen-feng, Hwang Lih-tyng, and J.C. Mollendorf
- Subjects
Fluid Flow and Transfer Processes ,Surface (mathematics) ,Materials science ,Mechanical Engineering ,Thermodynamics ,Mechanics ,Condensed Matter Physics ,Instability ,Stability (probability) ,Heat capacity ,Wavelength ,Schlieren ,Boundary value problem ,Layer (electronics) - Abstract
Using a simple non-linear density relation, the effect of the density extremum on the onset of thermal instability in a horizontally confined layer of water heated from below (at t1) and cooled from above (at t2) has been studied both experimentally and analytically. Both analytical and experimental results show that the density extremum has the effect of stabilizing the fluid layer. The effects of boundary conditions were also investigated. The analysis shows that realistic boundary conditions (finite thermal capacity bounding surfaces) tend to destabilize both with and without density extremum effects included. However, the qualitative behavior of Rac with R = ( t m − t 2 ) (t 1 − t 2 ) is relatively independent of the boundary conditions. The combined effect of both the density extremum and realistic boundary conditions is to destabilize (with respect to the Boussinesq limit of Rac = 1708) for large negative R; and to stabilize, by progressively larger amounts, as R increases. Different initial modes of instability for surface temperatures which spanned above and below 4°C were observed using a Schlieren system. The wavelengths of the observed distinct disturbance forms agree well with calculated wavelengths.
- Published
- 1984
225. Effects of dendrite axis and fusion boundary on stress corrosion cracking of ER 308 L/SS 304L welds in a high-temperature water environment.
- Author
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Lu, Wen-Feng, Huang, Jiunn-Yuan, Yung, Tung-Yuan, Chen, Tai-Cheng, and Tsai, Kun-Chao
- Subjects
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STRESS corrosion cracking , *HOT water , *WELDED joints , *DENDRITIC crystals , *FRACTURE mechanics , *BOILING water reactors - Abstract
This study investigated the effects of dendrite axis and fusion boundary (FB) on the stress corrosion cracking (SCC) of 308 L/304 L welds by using an alternating current potential drop (ACPD) technique to measure the SCC growth rates in a simulated boiling water reactor environment. The results show that the ferrite/austenite interfaces are more susceptible to SCC in the SS 308 L welds. Furthermore, the angle between the applied load and the dendrite axis affects the SCC growth rate, and as this angle approached 90°, the SCC crack growth rate increases. The SCC cracks in the heat affected zone (HAZ) are mainly intergranular and some cracks propagate transgranularly. Furthermore, the primary crack in the HAZ propagates along the FB; when reaching FB, some secondary cracks are arrested at the FB. The residual strain caused by weld shrinkage is the crucial factor for the increase in SCC susceptibility in HAZ. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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226. Two-Photon Fluorescence Microscopy and Applications in Angiogenesis and Related Molecular Events
- Author
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Lee, Marcus, Kannan, Sathya, Giridharan, Muniraj, Vinicius, Rosa, Lu, Wen Feng, Fuh, Jerry, Sriram, Gopu, and Cao, Tong
- Abstract
The role of angiogenesis in health and disease have gained considerable momentum in recent years. Visualizing angiogenic patterns and associated events of surrounding vascular beds in response to therapeutic and laboratory-grade biomolecules have become a commonplace in regenerative medicine and the biosciences. To aid imaging investigations in angiogenesis, the two-photon excitation fluorescence microscopy (2PEF), or multiphoton fluorescence microscopy is increasingly utilized in scientific investigations. The 2PEF microscope confers several distinct imaging advantages over other fluorescence excitation microscopy techniques – for the observation of in-depth, three-dimensional vascularity in a variety of tissue formats, including fixed tissue specimens and in vivo vasculature in live specimens. Understanding morphological and subcellular changes that occur in cells and tissues during angiogenesis will provide insights to behavioral responses in diseased states, advance the engineering of physiologically-relevant tissue models and provide biochemical clues for the design of therapeutic strategies. We review the applicability and limitations of the 2PEF microscope on the biophysical and molecular-level signatures of angiogenesis in various tissue models. Imaging techniques and strategies for best practices in 2PEF microscopy will be reviewed.
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- 2021
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227. Artificial neural network-based geometry compensation to improve the printing accuracy of selective laser melting fabricated sub-millimetre overhang trusses
- Author
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Hong, Ruochen, Zhang, Lei, Lifton, Joseph, Daynes, Stephen, Wei, Jun, Feih, Stefanie, and Lu, Wen Feng
- Abstract
Selective laser melting processes deposit and join metal powders to near net shape in a layer-by-layer manner. The process of melting and re-solidification of several layers of deposited material can result in geometric deviations, and the impact is particularly significant for sub-millimetre structures oriented at a wide range of overhang angles with respect to the building platform. This paper assesses and benchmarks the capabilities of a neural network-based geometric compensation approach for truss lattice structures with circular cross-sections. The neural network method is capable to generate free-form cross-sections with enhanced geometric freedom for compensation compared to more established analytical compensation approaches limited to predefined geometric shapes. For neural network training, lattice dome structures composed of trusses with different overhang angles were designed and printed by selective laser melting and measured via X-ray computed tomography, resulting in point cloud data sets containing more than 20,000 data points for each overhang angle. For experimental validation, neural network-compensated dome structures were benchmarked against dome structures with elliptical parameter compensation. Results show that the neural network compensated lattice trusses achieve higher printing dimensional accuracy compared to the uncompensated structures and those compensated based on elliptical parameter estimates.
- Published
- 2021
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228. Mechanism in scratching of calcium fluoride with magneto-plasticity.
- Author
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Guo, Yunfa, Zhan, Jiaming, Lu, Wen Feng, and Wang, Hao
- Subjects
- *
CALCIUM fluoride , *MAGNETIC field effects , *MAGNETIC flux density , *DISLOCATION nucleation , *BRITTLE materials - Abstract
• The mechanism in scratching of CaF 2 with magneto-plasticity is uncovered. • A magnetic field significantly suppresses surface damage. • Brittle fracture is reduced by lower scratching stress with magneto-plasticity. • Dislocation nucleation and mobility are enhanced under a magnetic field. • A novel analysis of energy criterion and crystal plasticity is proposed. Magnetic field-tuned dislocation plasticity (i.e., magneto-plasticity) has attracted growing attention for assistance to limit the damage evolution of brittle ceramics in the material removal process. However, the mechanism controlling material removal of brittle ceramics with magneto-plasticity remains far from clear. Therefore, combined stress field modeling and molecular dynamics (MD) simulations were performed for scratching of a ceramic material, calcium fluoride (CaF 2), to investigate the magneto-plasticity mechanism during the material removal process of brittle ceramics. The stress field calculation with magneto-plasticity was first conducted, which suggests a general reduction in scratching stress on the subsurface under the magnetic field effect. It is also found that the degree of reduction in scratching stress is significantly influenced by the magnetic field intensity and direction as well as strain rate. The reduced scratching stress is responsible for the suppressed formation and evolution of cracks and defects in scratching. Subsequently, MD simulations in scratching of CaF 2 show that the application of a magnetic field can facilitate dislocation nucleation, enlarge the range of dislocation propagation, and regularize the dislocation distribution, indicating the advancement in elastic-plastic transition and dislocation mobility. From the views of energy criterion and crystal plasticity, a magnetic field can decrease the required work and resolved shear stress for dislocation slip, which results in a lower scratching stress level. The combined theoretical method of this study broadens the comprehension of magneto-plasticity on deformation mechanism in the material removal process of ceramics and offers theoretical direction for the application of magnetic field assistance in ceramic processing. [Display omitted] [ABSTRACT FROM AUTHOR]
- Published
- 2024
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229. Pluronic F127 blended polycaprolactone scaffolds via e-jetting for esophageal tissue engineering.
- Author
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Wu, Bin, Takeshita, Nobuyoshi, Wu, Yang, Vijayavenkataraman, Sanjairaj, Ho, Khek Yu, Lu, Wen Feng, and Fuh, Jerry Ying Hsi
- Subjects
TISSUE scaffolds ,ELECTROHYDRODYNAMICS ,POLYCAPROLACTONE ,CELL adhesion ,TENSILE strength ,CELL migration ,FIBROBLASTS ,TISSUE engineering - Abstract
Several attempts have been made to fabricate esophageal tissue engineering scaffolds. However, most of these scaffolds possess randomly oriented fibres and uncontrollable pore sizes. In order to mimic the native esophageal tissue structure, electro-hydrodynamic jetting (e-jetting) was used in this study to fabricate scaffolds with aligned fibres and controlled pore size. A hydrophilic additive, Pluronic F127 (F127), was blended with polycaprolactone (PCL) to improve the wettability of the scaffolds and hence the cell adhesion. PCL/F127 composite scaffolds with different weight ratios (0-12%) were fabricated. The wettability, phase composition, and the mechanical properties of the fabricated scaffolds were investigated. The results show that the e-jetted scaffolds have controllable fibres orientated in two perpendicular directions, which are similar to the human esophagus structure and suitable pore size for cell infiltration. In addition, the scaffolds with 8% F127 exhibited better wettability (contact angle of 14°) and an ultimate tensile strength (1.2 MPa) that mimics the native esophageal tissue. Furthermore, primary human esophageal fibroblasts were seeded on the e-jetted scaffolds. PCL/F127 scaffolds showed enhanced cell proliferation and expression of the vascular endothelial growth factor (VEGF) compared to pristine PCL scaffolds (1.5- and 25.8- fold increase, respectively; P < 0.001). An in vitro wound model made using the PCL/F127 scaffolds showed better cell migration than the PCL scaffolds. In summary, the PCL/F127 e-jetted scaffolds offer a promising strategy for the esophagus tissue repair.
[ABSTRACT FROM AUTHOR]
- Published
- 2018
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230. Homogeneous cell printing on porous PCL/F127 tissue engineering scaffolds
- Author
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Wu, Bin, Li, Shihao, Shi, Jia, Vijayavenkataraman, Sanjairaj, Lu, Wen Feng, Trau, Dieter, and Fuh, Jerry Ying Hsi
- Abstract
In tissue engineering, cell-laden scaffold has gradually replaced cell-less scaffold due to better biological performance. However, manual pipetting, the traditional cell seeding for cell-laden scaffold, leads to an imprecise and inhomogeneous cell distribution. As an alternative, micro-extrusion of cell-laden hydrogel achieves homogenous cell distribution, but causes high shear stress which is harmful to cells. To address this challenge, the objective of this study is to print cells on porous scaffold precisely without causing high shear stress to produce homogeneous cell-laden hybrid scaffold. Porous polycaprolactone scaffold fabricated through electro-hydrodynamic jetting was used as a representation. To improve scaffold hydrophilicity for better cell adhesion, 6% (w/w) Pluronic F127 was blended with polycaprolactone. HeLa cells, as a demonstration, were ejected on the scaffold fibers through piezoelectric inkjet printing. As a result, inkjet printing showed a more precise and homogeneous cell distribution and enhanced cell proliferation compared to manual pipetting (1.34- fold increase after 7 days). Furthermore, due to the low viscosity of cell solution, the average shear stress caused during inkjet printing was 1.79 kPa as opposed to 18 kPa of micro-extrusion, which is friendly to cells. In summary, through inkjet printing, homogeneous cell-laden hybrid scaffold could be fabricated with lower shear stress.
- Published
- 2018
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231. Comparison of base classifiers for multi-label learning.
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Yapp, Edward K. Y., Li, Xiang, Lu, Wen Feng, and Tan, Puay Siew
- Subjects
- *
SUPPORT vector machines , *LABELS , *DECISION trees - Abstract
Multi-label learning methods can be categorised into algorithm adaptation, problem transformation and ensemble methods. Some of these methods depend on a base classifier and the relationship is not well understood. In this paper the sensitivity of five problem transformation and two ensemble methods to four types of classifiers is studied. Their performance across 11 benchmark datasets is measured using 16 evaluation metrics. The best classifier is shown to depend on the method: Support Vector Machines (SVM) for binary relevance, classifier chains, calibrated label ranking, quick weighted multi-label learning and RAndom k -labELsets; k -Nearest Neighbours (k -NN) and Naïve Bayes (NB) for Hierarchy Of Multilabel classifiERs; and Decision Trees (DT) for ensemble of classifier chains. The statistical performance of a classifier is also found to be generally consistent across the metrics for any given method. Overall, DT and SVM have the best performance–computational time trade-off followed by k -NN and NB. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
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232. Semantic-aware short path adversarial training for cross-domain semantic segmentation.
- Author
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Shan, Yuhu, Chew, Chee Meng, and Lu, Wen Feng
- Subjects
- *
PHYSIOLOGICAL adaptation - Abstract
Recently, many methods have been proposed to deal with the problem of cross-domain semantic segmentation. Most of them choose to conduct domain adversarial training either on the high-level convolutional neural network (CNN) features or on the output segmentation maps. Typically, a relatively small weight is given to the adversarial training loss to avoid the problem of mode collapse. However, one potential weakness of these methods is that low-level CNN layers may receive little gradients for domain adaptation, especially when the network is deep. To address this problem, we propose to conduct an auxiliary adversarial training on the fused multi-level CNN features. Gradients for domain adaptation can thus flow into low-level CNN layers more easily along a shorter path. Experiments are conducted on the dataset of Cityscapes with using the source datasets of GTA5 and SYNTHIA, respectively. Quantitative and qualitative results certify the efficacy of the proposed method. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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- View/download PDF
233. Design concepts for generating optimised lattice structures aligned with strain trajectories.
- Author
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Daynes, Stephen, Feih, Stefanie, Lu, Wen Feng, and Wei, Jun
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- *
UNIFORM spaces , *SPECIFIC gravity , *THREE-dimensional printing , *MANUFACTURING processes , *BANACH lattices - Abstract
Additively manufactured lattice structures enable the realisation of light-weight, multi-functional, structures. For example, lattices can be used for high stiffness and buckling resistance in sandwich structures or as support material for additive manufacturing. Topology optimisation and additive manufacturing are two technologies that allow the design, optimisation and manufacture of complex lattice designs. In this work, a new lattice optimisation methodology is presented that tailors the size, shape and orientation of individual lattice trusses in three-dimensional space by using principal strain fields obtained from topology optimisation. This new method of generating functionally graded lattices is shown both numerically and experimentally to be capable of generating lattice structures with greatly improved stiffness and strength when compared to lattice structures with a uniform lattice infill. Upper and lower relative density thresholds and minimum truss member sizes are included in the optimisation workflow to ensure that the optimised lattice designs are compatible with additive manufacturing process constraints. The functional grading method is also shown to be capable of generating conformal lattice structures in three dimensions, even for complex loading conditions and arbitrary volume boundaries. • A novel lattice infill methodology creates optimally aligned lattice structures. • Lattice structures are automatically generated using principal strain trajectories. • The lattices conform to arbitrary 3D design space volumes. • Optimally aligned lattice structures have higher stiffness and strength. • Additively manufactured lattices validate the optimisation predictions. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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234. A real-time approach for failure detection in material extrusion process based on artificial neural network.
- Author
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Pan, Wanbin, Jiang, Hongyi, Wang, Shufang, Lu, Wen Feng, Cao, Weijuan, and Weng, Zhenlei
- Subjects
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EXTRUSION process , *FRACTURE mechanics , *MANUFACTURING processes , *ARTIFICIAL neural networks - Abstract
Purpose: This paper aims to detect the printing failures (such as warpage and collapse) in material extrusion (MEX) process effectively and timely to reduce the waste of printing time, energy and material. Design/methodology/approach: The approach is designed based on the frequently observed fact that printing failures are accompanied by abnormal material phenomena occurring close to the nozzle. To effectively and timely capture the phenomena near the nozzle, a camera is delicately installed on a typical MEX printer. Then, aided by the captured phenomena (images), a smart printing failure predictor is built based on the artificial neural network (ANN). Finally, based on the predictor, the printing failures, as well as their types, can be effectively detected from the images captured by the camera in real-time. Findings: Experiments show that printing failures can be detected timely with an accuracy of more than 98% on average. Comparisons in methodology demonstrate that this approach has advantages in real-time printing failure detection in MEX. Originality/value: A novel real-time approach for failure detection is proposed based on ANN. The following characteristics make the approach have a great potential to be implemented easily and widely: (1) the scheme designed to capture the phenomena near the nozzle is simple, low-cost, and effective; and (2) the predictor can be conveniently extended to detect more types of failures by using more abnormal material phenomena that are occurring close to the nozzle. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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235. Optimisation of functionally graded lattice structures using isostatic lines.
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Daynes, Stephen, Feih, Stefanie, Lu, Wen Feng, and Wei, Jun
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LATTICE theory , *ABSTRACT algebra , *ISOSTATIC pressing , *HIGH pressure (Technology) , *POWDER metallurgy - Abstract
Functionally graded lattice core structures show a gradual and localised variation in their mechanical properties with the aim of improving structural performance whilst minimising weight. We present a novel approach to generate optimised functionally graded lattice core structures. Firstly, topology optimisation is performed to return the optimal core density distribution to minimise the structure's compliance subject to a mass constraint. A series of isostatic lines are then constructed with respect to the local principal stresses to generate a lattice structure spatially graded with respect to lattice cell size, aspect ratio and orientation. To validate this novel approach, optimisation is performed on a sandwich core structure subject to three point bending. Experimental tests confirm the greatly improved stiffness and strength properties (101% and 172% respectively) of the core as a result of spatially grading the lattice cells when compared to a benchmark core with uniform cell size of the same density. The new approach also significantly outperforms lattice structures with graded diameters as optimised by state-of-the-art commercial software packages. Non-dimensional core performance indices are formulated to express the relative specific stiffness and strength properties of the core for the three design approaches. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
236. Short- and long-term outcomes of laparoscopic versus open liver resection for large hepatocellular carcinoma: a propensity score study.
- Author
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Zhang, Kang-Jun, Liang, Lei, Diao, Yong-Kang, Xie, Ya-Ming, Wang, Dong-Dong, Xu, Fei-Qi, Ye, Tai-Wei, Lu, Wen-Feng, Cheng, Jian, Shen, Guo-Liang, Yao, Wei-Feng, Lu, Yi, Xiao, Zun-Qiang, Zhang, Jun-Gang, Zhang, Cheng-Wu, Huang, Dong-Sheng, and Liu, Jun-Wei
- Subjects
- *
LIVER surgery , *LAPAROSCOPIC surgery , *PROPENSITY score matching , *SURGICAL complications , *LIVER , *PATIENT selection - Abstract
Purpose: Laparoscopic liver resection (LLR) for hepatocellular carcinoma (HCC) remains controversial, especially for tumors larger than 5 cm. We compared the short- and long-term outcomes of laparoscopic and open liver resection (OLR) for large HCC. Methods: Patients with large HCC after curative hepatectomy were enrolled. To compare the short-term outcomes, propensity score matching (PSM) and inverse probability treatment weighting (IPTW) were performed to reduce the effect of confounding factors, respectively. Subsequently, Cox-regression analyses were conducted to identify the independent risk factors associated with decreased recurrence-free survival (RFS) and poor overall survival (OS). Result: There were 265 patients enrolled in the final analysis: 146 who underwent OLR and 119 who underwent LLR. There was no significant difference between the OLR and LLR groups according to PSM and IPTW analysis (all P > 0.05). Multivariable analysis revealed that LLR was not independently associated with poorer OS (HR 1.15, 95% CI 0.80–1.67, P = 0.448) or RFS (HR 1.22, 95% CI 0.88–1.70, P = 0.238). Conclusion: There were no significant differences in perioperative complications or long-term prognosis between LLR and OLR for large HCC, which provides evidence for standard laparoscopic surgical practice with adequate surgeon experience and careful patient selection. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
237. Adaptation of the Product Structure-based Integrated Life cycle Analysis (PSILA) technique for carbon footprint modelling and analysis of closed-loop production systems.
- Author
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Low, Jonathan Sze Choong, Tjandra, Tobias Bestari, Lu, Wen Feng, and Lee, Hui Mien
- Subjects
- *
ECOLOGICAL impact , *CLOSED loop systems , *MANUFACTURING processes , *DECISION making , *DECISION support systems - Abstract
In a previous work, the Product Structure-based Integrated Life cycle Analysis (PSILA) technique was developed to conduct cost modelling and analysis of closed-loop production systems. In this paper, we expand the utility of this technique into carbon footprint (CFP) modelling and analysis of closed-loop production systems – enabling companies to make informed decisions on whether to adopt closed-loop production based not only on economic but also environmental performance. A description of the PSILA technique applied for carbon footprint modelling and analysis is explained, followed by a case study of closed-loop production of a flat-panel display (FPD) monitor to validate the technique. We verified the CFP result simulated by the model built through the PSILA technique, or PSILA-CFP model in short, against the result generated by a model built through the conventional Life Cycle Assessment (LCA) method. A benchmarking analysis was then conducted to compare the closed-loop production system against the linear production system. Through this analysis, we demonstrated how the CFP result can be broken down based on the product structure, thus enabling us to granularise the result and trace the impact of implementing a closed-loop production system to the individual modules, components and materials that are recovered, reutilised or treated in the system. The results were able to show that the implementation of the closed-loop production system for the FPD monitor can potentially result in an overall CFP reduction of 39.91 million kg CO 2 e, of which 90.03% is contributed by the closed-loop recycling of ABS. The other significant contributors of CFP reduction are from the closed-loop material recycling of the aluminium, which accounts for 8.13 million kg CO 2 e or 20.37% of the total CFP reduction. A sensitivity analysis was also carried out to investigate the effects of data uncertainties, which may invalidate assumptions made in the case study. In summary, we have successfully adapted the PSILA technique so as to provide decision support in the form of analytical insights on how a closed-loop production system will perform in terms of carbon footprint, why it performs this way and what to look out for if the decision is made to implement such a system. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
238. A quantitative aesthetic measurement method for product appearance design.
- Author
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Hu, Huicong, Liu, Ying, Lu, Wen Feng, and Guo, Xin
- Subjects
- *
PRODUCT design , *INFLUENCE , *AESTHETICS - Abstract
Product appearance is one of the crucial factors that influence consumers' purchase decisions. The attractiveness of product appearance is mainly determined by the inherent aesthetics of the design composition related to the arrangement of visual design elements. Hence, it is critical to study and improve the arrangement of visual design elements for product appearance design. Strategies that apply aesthetic design principles to assist designers in effectively arranging visual design elements are widely acknowledged in both academia and industry. However, applying aesthetic design principles relies heavily on the designer's perception and experience, while it is rather challenging for novice designers. Meanwhile, it is hard to measure and quantify design aesthetics in designing artefacts when designers refer to existing successful designs. In this regard, this study aims to introduce a method that assists designers in applying aesthetic design principles to improve the attractiveness of product appearance. Furthermore, formulas for aesthetic measurement based on aesthetic design principles are also developed, and it makes an early attempt to provide quantified aesthetic measurements of design artefacts. A case study on camera design was conducted to demonstrate the merits of the proposed method where the improved strategies for the camera appearance design offer insights for concept generation in product appearance design based on aesthetic design principles. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
239. Fracture toughness characteristics of additively manufactured Ti–6Al–4V lattices.
- Author
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Daynes, Stephen, Lifton, Joseph, Lu, Wen Feng, Wei, Jun, and Feih, Stefanie
- Subjects
- *
FRACTURE toughness , *SPECIFIC gravity , *DEAD loads (Mechanics) , *ELASTIC modulus - Abstract
Metallic lattice structures are well known for having high specific elastic moduli and strength. However, very little is understood about their resistance to fracture. In this work Ti–6Al–4V lattice structures are additively manufactured by selective laser melting and their fracture toughness characteristics are investigated. Resistance to fracture was determined under Mode-I loading at static rates using an extended compact tension (EC(T)) specimen, modified to contain lattice cells. The lattices consist of octet cells with a 3.5 mm edge length and relative densities ranging from 25% to 56%. Toughness is shown to increase by a power law with relative density and this trend was also obtained with finite element models. A new functional grading optimisation methodology is also presented for increasing fracture toughness. The size optimisation results in a functionally graded lattice whereby lattice truss diameters become the design variables. After size optimisation, initiation fracture toughness increases by up to 37%. Image 1 • Novel optimisation method for generating lattices with high fracture toughness. • Crack size effect on toughness is suppressed by tailoring lattice truss diameters. • Additively manufactured lattices validate FE models with good agreement. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
240. 3D-printed ceramic triply periodic minimal surface structures for design of functionally graded bone implants.
- Author
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Vijayavenkataraman, Sanjairaj, Kuan, Lai Yee, and Lu, Wen Feng
- Subjects
- *
MINIMAL surfaces , *BONES , *CERAMIC materials , *SURFACE structure , *FUNCTIONALLY gradient materials , *CERAMIC material manufacturing , *YOUNG'S modulus - Abstract
Stress shielding is one of the main problems that lead to bone resorption and revision surgery after implantation. Most of the commercially available metallic non-porous bone implants have a much greater stiffness than the native human bones and are prone to cause stress-shielding. With an open cell structure and intricate architecture, hyperbolic minimal surfaces offer several advantages such as less stress concentration, high permeability and high surface area to volume ratio, thus providing an ideal environment for cell adhesion, migration, and proliferation. This paper explores the use of porous bone implant design based on Triply Periodic Minimal Surfaces (TPMS) which is additively manufactured with ceramic material (Alumina) using Lithography-based Ceramics Manufacturing (LCM) technology. A total of 12 different primitive surface structure unit cells with pore size in the range of 500–1000 μm and porosity above 50% were considered. This is one of the earliest studies reporting the 3D printing of TPMS-based structures using ceramic material. Our results suggest that the choice of material and a porous TPMS-based design led to fabrication of structures with a much lesser compressive modulus comparable with the native bone and hence could potentially be adopted for bone implant design to mitigate the stress-shielding effect. Unlabelled Image • 3D-printed ceramic hyperbolic surface structures exhibit Young's modulus values between 2-5.5 GPa comparable to native bone • The open cell structure & intricate architecture offer conducive cell-microenvironment (high surface area to volume ratio) • Difficulty in slurry removal with smaller unit cell sizes (<2 mm) resulted in greater mass deviations (up to 100%) • An equation is derived to find the theoretical Young's modulus of the printed structures for proprietary materials • A functionally-graded structure for the trochanter region of hip implant is designed to mitigate stress-shielding effects [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
241. Pseudo-ductile fracture of 3D printed alumina triply periodic minimal surface structures.
- Author
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Zhang, Lei, Feih, Stefanie, Daynes, Stephen, Chang, Shuai, Wang, Michael Yu, Wei, Jun, and Lu, Wen Feng
- Subjects
- *
ALUMINUM oxide , *MINIMAL surfaces , *STEREOLITHOGRAPHY , *ABSORPTION , *POROUS materials - Abstract
Additive manufacturing enables the fabrication of periodic ceramic lattices with controllable micro-architectures. Many studies reported their catastrophic brittle fracture behaviour. However, ceramic lattices may fail by a layer-by-layer pseudo-ductile fracture mode, by controlling micro-architectures and porosities. Moreover, their fracture behaviour can be optimised by introducing strut/wall thickness gradients. This paper investigates the fracture behaviour and the fracture mode transition of ceramic triply periodic minimal surface (TPMS) structures. Alumina TPMS structures with relative densities of 0.14-0.37 are fabricated by ceramic stereolithography. Quasi-static compression tests validate a transition density range for non-graded samples: low (<0.21) and moderate (>0.25) relative density samples show layer-by-layer pseudo-ductile and catastrophic brittle fracture modes, respectively. The pseudo-ductile failure mode increases the energy absorption performance, enabling load-bearing capacity for a compressive strain up to 50%. With appropriate thickness gradients, graded structures exhibit significant increase of energy absorption without a decrease of fracture strength compared to their non-graded counterparts. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
242. 3D printing microlattice interpenetrating phase composites for energy absorption, damage resistance, and fracture toughness.
- Author
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Guo, Xiao, Hu, Yuwei, Li, Xinwei, Fuh, Jerry Ying Hsi, and Lu, Wen Feng
- Subjects
- *
FRACTURE toughness , *THREE-dimensional printing , *HARD materials , *MINIMAL surfaces , *ABSORPTION - Abstract
• Multi-material printing interpenetrating phase composites with controlled mechanical properties. • Stable mechanical reponse for energy absorption, damage tolerance and fracture tougness. • Strengthening and toughening mechanisms of IPCs. Under external load, lightweight cellular solids are often associated with localized deformation that would lead to their catastrophic failure. Cellular solids are thus often infilled with a soft secondary material, constituting interpenetrating phase composites. Owing to highly interconnected porous architectures and controllable smooth surfaces, the triply periodic minimal surface structures based on interpenetrating phase composites are investigated in this paper. Samples are fabricated via polyjet multi-material printing, with the hard material taking on the primitive lattice and the soft material taking on its inverse. Quasi-static compression and three-point bending tests were performed on the fabricated composites. Results show that the combination of high stiffness, strength, and prolonged smooth plateau stress endows the composites to be promising for lightweight materials and energy absorbers. The designed composites can exhibit an excellent fracture toughness of 0.51 MPa•m1/2. Moreover, the designed interpenetrating architectures and stiff-contrast materials intrinsically control the strengthening and toughening mechanisms. The findings presented here demonstrate the potential to obtain enhanced mechanical properties by combining the advantages of the multi-material printing technique and interpenetrated design. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
243. Electrohydrodynamic jet 3D-printed PCL/PAA conductive scaffolds with tunable biodegradability as nerve guide conduits (NGCs) for peripheral nerve injury repair.
- Author
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Vijayavenkataraman, Sanjairaj, Thaharah, Siti, Zhang, Shuo, Lu, Wen Feng, and Fuh, Jerry Ying Hsi
- Subjects
- *
ELECTROHYDRODYNAMICS , *THREE-dimensional printing , *GENE expression , *MOLECULAR genetics , *POLYMERASE chain reaction - Abstract
Abstract NGCs are considered as an alternative treatment method for treating peripheral nerve injuries in place of nerve autografts. Biomimicry, conductivity, and biodegradability are the properties expected of an ideal NGC. PCL/PAA NGCs with three different concentrations of PAA (2.5, 5 and 7.5%) were fabricated using EHD-jet 3D printing. The mechanical properties of the PCL/PAA NGCs mimic the native human nerve properties (ultimate tensile strength of 6.5 to 11.7 MPa) and the conductivity match that of the amphibian motor nerve fiber myelin sheath (10−6 S/cm). The in vitro degradation studies reveal that they are biodegradable and injury/site-specific biodegradability can be obtained by tuning the PCL/PAA concentration ratio. In addition, PAA being a polyanionic polymer has the potential to act as a cation-exchanger, mimicking the functions of the nerve cortical gel layer, thereby influencing the electrophysiological phenomena called nerve excitation and conduction. Neural differentiation studies with PC12 cells assessed by the Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and immunocytochemistry showed enhanced gene expression with the presence of PAA. Our results suggest that the EHD-jet 3D printed porous conductive PCL/PAA NGCs has the potential to be used in the treatment of peripheral nerve injuries. Graphical abstract Unlabelled Image Highlights • Ideal Nerve Guide Conduits with biomimicry and conductivity were fabricated using Electrohydrodynamic Jet 3D Printing • The mechanical properties and conductivity of the scaffolds mimic the native human nerve properties • Poly(acrylic acid) as cation-exchanger mimics nerve cortical gel layer functions, influencing nerve excitation & conduction • PC12 in vitro neural differentiation studies showed enhanced gene expression with the presence of Poly(acrylic acid) • Can potentially be used to treat peripheral nerve injuries & neurodegenerative conditions (Alzheimer's and Parkinson's) [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
244. Simultaneously improving mechanical, thermal, and anti-wear properties of Ti alloys using 3D-networked graphene as reinforcement.
- Author
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Yan, Qi, Chen, Biao, Ye, Wenting, Zhang, Tao, Wan, Jie, Zhou, Qing, Shen, Jianghua, Li, Jinshan, Lu, Wen Feng, and Wang, Hao
- Subjects
- *
TITANIUM composites , *ALUMINUM composites , *GRAPHENE , *SOLUTION strengthening , *MECHANICAL wear , *METALLIC composites , *HEAT transfer , *ALLOYS - Abstract
The simultaneous improvement of mechanical and functional properties of Ti alloys is of considerable significance for their diverse applications and service life. Incorporating graphene with Ti is hoping to realize that, however, it is challenging to achieve the improvement because of the poor chemical stability of carbon/Ti systems. This challenge becomes particularly significant when using high carbon-content reinforcements, as the reinforcement agglomeration is considered to adversely affect composite performances. In this work, an efficient powder metallurgy method was developed to fabricate titanium matrix composites reinforced by a high content of graphene nanosheets (GNSs). Quasi-continuous GNSs were arranged in a 3D network and were surrounded by in-situ TiC. The results revealed that the load-transfer and solid-solution strengthening factors contributed to the high mechanical strength of the composites. Moreover, the GNS networks conduced to the improvement of thermal conduction, reduced the total weight, and enhanced the anti-wear performance of the composites via self-lubrication. Furthermore, the proposed approach can be applied to other carbon/metal composites for achieving significant improvements in their performance. [Display omitted] • An overall improved property is realized in high-contents graphene/Ti composites. • Load transfer and solid solution factors strengthen the compressive yield strength. • Dense-agglomerated graphene nanosheets build a channel for thermal energy transfer. • Self-lubrication of graphene decreases coefficient of friction and wear loss. • The proposed approach and mechanism can be applied to other carbon/metal systems. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
245. Predictive modelling for enhanced scratching of brittle ceramics with magneto-plasticity.
- Author
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Guo, Yunfa, Zhan, Jiaming, Lee, Yan Jin, Lu, Wen Feng, and Wang, Hao
- Subjects
- *
MAGNETIC flux density , *PREDICTION models , *MAGNETIC crystals , *STRESS concentration , *CERAMICS - Abstract
• A magneto-plastic predictive model of ductile-brittle transition is presented. • The model reveals the relationship between magneto-plasticity and strain rate. • MD simulations identify anisotropic dislocation slip and subsurface stress. • Enhanced ductile-brittle transition across magnetic field and crystal orientations. • Magnetic field improves dislocation-dominant lateral and tangential plastic flow. The micro-cutting of brittle ceramics starts with elastic-plastic deformation followed by severe brittle fracture, which significantly restricts the machinability and application of these materials. Magnetic field-enhanced plasticity (i.e., magneto-plasticity) has shown a positive potential to augment the ductile-brittle transition and machinability but the material removal mechanism of brittle ceramics with magneto-plasticity and its dependence on strain rate remains unclear. In this study, a deformation energy-based model was developed to bring light to the deformation mechanisms affecting the ductile-brittle transition under magneto-plasticity and the corresponding dependency on strain rate. MD simulations assisted the analytical modeling by deriving the orientation-dependent dislocation movement and stress distribution that contribute to single-crystal anisotropy in the surface formation and ductile-brittle transitions during scratching. The proposed model accurately predicted the improvement in ductile-brittle transition under various magnetic field intensities and orientations as confirmed in the experimental magnetic field-enhanced micro-scratching tests on single-crystal calcium fluoride (CaF 2). Scratched surface morphologies, acoustic emission (AE) signals, and critical loading conditions demonstrated the improvements in ductile-brittle transition with magneto-plasticity. Additionally, the progression of lateral slip trace and tangential surface pile-up under various magnetic field conditions confirm the direct influence of magneto-plasticity on dislocation mobility and the change in surface formation mechanism of brittle ceramics. This study not only deepens the understanding of the manifestation of magneto-plasticity during the deformation of brittle ceramics, but also opens new avenues for the integration of magnetic field-assisted technology in manufacturing processes. [Display omitted] [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
246. Buckling optimization of Kagome lattice cores with free-form trusses.
- Author
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Zhang, Lei, Feih, Stefanie, Daynes, Stephen, Wang, Yiqiang, Wang, Michael Yu, Wei, Jun, and Lu, Wen Feng
- Subjects
- *
LIGHTWEIGHT construction , *CRYSTAL lattices , *MECHANICAL buckling , *TRUSSES , *STRUCTURAL failures , *FOURIER series - Abstract
Lightweight lattice structures are an important class of cellular structures with high potentials for multi-functional applications. Considering load-bearing requirements, truss buckling is one of the main failure mechanisms for low density and slender lattice structures. Critical buckling loads can be increased by modifying the profile of a truss. In this paper, we present a shape design method to optimize the critical buckling loads for lattice cores with free-form trusses. The free-form truss is represented by Fourier series and implicit surfaces, having smooth truss diameter variations and truss joints. The optimized truss profile is obtained by solving a parametric shape optimization problem with Fourier series coefficients as design variables. The method is used for designing optimized 1D columns and 3D Kagome lattice cores for sandwich panels. The numerical results predict 26.8% and 20.4% improvements of the critical buckling loads for 1D columns and 3D Kagome lattice cores compared to their uniform counterparts of the same mass, respectively. The optimized structures include complex smooth and curved geometries that are well suited for additive manufacturing because of the greater design freedom. Finally, the initial and optimized lattice cores are additively manufactured and tested. The experimental results validate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
247. Gauging Image and Video Quality in Industrial Applications
- Author
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Lin, Weisi, Kacprzyk, Janusz, editor, Liu, Ying, editor, Sun, Aixin, editor, Loh, Han Tong, editor, Lu, Wen Feng, editor, and Lim, Ee-Peng, editor
- Published
- 2008
- Full Text
- View/download PDF
248. Artificial Intelligence Applied to the Modeling and Implementation of a Virtual Medical Office
- Author
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de Almeida, Sandro Moretti Correia, Brasil, Lourdes Mattos, Ferneda, Edilson, Carvalho, Hervaldo Sampaio, de Silva, Renata Pariva, Kacprzyk, Janusz, editor, Liu, Ying, editor, Sun, Aixin, editor, Loh, Han Tong, editor, Lu, Wen Feng, editor, and Lim, Ee-Peng, editor
- Published
- 2008
- Full Text
- View/download PDF
249. DICOM-Based Multidisciplinary Platform for Clinical Decision Support: Needs and Direction
- Author
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Chan, Lawrence Wing-Chi, Chan, Phoebe Suk-Tak, Zheng, Yongping, Wong, Alex Ka-Shing, Liu, Ying, Benzie, Iris Frances Forster, Kacprzyk, Janusz, editor, Liu, Ying, editor, Sun, Aixin, editor, Loh, Han Tong, editor, Lu, Wen Feng, editor, and Lim, Ee-Peng, editor
- Published
- 2008
- Full Text
- View/download PDF
250. Model Construction for Knowledge-Intensive Engineering Tasks
- Author
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Stein, Benno, Kacprzyk, Janusz, editor, Liu, Ying, editor, Sun, Aixin, editor, Loh, Han Tong, editor, Lu, Wen Feng, editor, and Lim, Ee-Peng, editor
- Published
- 2008
- Full Text
- View/download PDF
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