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Enhancing strength and plasticity by pre-introduced indent-notches in Zr36Cu64 metallic glass:A molecular dynamics simulation study

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Journal of Materials Science & Technology 2020年第8期36卷 119-125页

作者： Shidong Feng Lin Li K.C.Chan Lei Zhao Limin Wang Riping Liu State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004China Advanced manufacturing Technology Research Centre Department of Industrial and Systems EngineeringThe Hong Kong Polytechnic University999077Hong KongChina Department of Metallurgical and Materials engineering The University of AlabamaTuscaloosaAL35487USA

The deformation behavior in Zr36 Cu64 metallic glasses with pre-introduced indent-notches has been studied by molecular dynamics simulation at the atomic *** indent-notches can trigger the formation of densely-packed clusters composed of solid-like atoms in the indent-notch affected *** denselypacked clusters are highly resistant to the nucleation of shear ***,there is more tendency for the shear bands to nucleate outside the indent-notch affected zone,which enlarges the deformation region and enhances both the strengthening effect and the plastic deformation *** indent-notched MGs,when determining the initial yielding level,there is a competition process occurring between the densely-packed clusters leading to the shear band formation outside the indent-notch affected zone and the stress-concentration localizing deformation around the notch *** the indent-notch depth is small,the stress-concentration around the notch root plays a dominant role,leading to the shear bands initiating from the notch root,reminiscence of the *** the indent-notch depth increases,there are many densely-packed clusters with high resistance to deformation in the indent-notch affected zone,leading to the shear band formation from the interface between the indent-notch affected zone and the *** research findings provide a feasible means for improving the strength and the plasticity of metallic glasses at room temperature.

关键词： Metallic glass Notch Shear band Microstructure Molecular dynamics simulation

Statecharts for Distributed Product Data Management System Modelling

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厦门大学学报（自然科学版） 2002年第S1期41卷 260-261页

作者： K K Leong K M Yu W B Lee Department of industrial & systems engineering The Hong Kong Polytechnic UniversityDepartment of Industrial & Systems Engineering The Hong Kong Polytechnic UniversityDepartment of Industrial & Systems EngineeringThe Hong Kong Polytechnic University Hong Kong ChinaHong Kong ChinaHong Kong China

Product data management (PDM) has been accepted as an important tool for the manufacturing industries. In recent years, more and mor e researches have been conducted in the development of PDM. Their research area s include system design, integration of object-oriented technology, data distri bution, collaborative and distributed manufacturing working environment, secur ity, and web-based integration. However, there are limitations on their rese arches. In particular, they cannot cater for PDM in distributed manufacturing e nvironment. This is especially true in South China, where many Hong Kong (HK) ma nufacturers have moved their production plants to different locations in Pearl R iver Delta for cost reduction. However, they retain their main offices in HK. Development of PDM system is inherently complex. Product related data cover prod uct name, product part number (product identification), drawings, material speci fications, dimension requirement, quality specification, test result, log size, production schedules, product data version and date of release, special tooling (e.g. jig and fixture), mould design, project engineering in charge, cost spread sheets, while process data includes engineering release, engineering change info rmation management, and other workflow related to the process information. Accor ding to Cornelissen et al., the contemporary PDM system should contains manageme nt functions in structure, retrieval, release, change, and workflow. In system design, development and implementation, a formal specification is nece ssary. However, there is no formal representation model for PDM system. Theref ore a graphical representation model is constructed to express the various scena rios of interactions between users and the PDM system. Statechart is then used to model the operations of PDM system, Fig.1. Statechart model bridges the curr ent gap between requirements, scenarios, and the initial design specifications o f PDM system. After properly analyz

关键词： DPDM Statecharts for Distributed Product Data Management System Modelling

RE-engineering TRANSFORMER MAINTENANCE PROCESSES TO IMPROVE CUSTOMIZED SERVICE DELIVERY

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Journal of systems Science and systems engineering 2011年第3期20卷 323-345页

作者： Amy J.C. TRAPPEY Yong SUN Charles V. TRAPPEY Lin MA Department of industrial engineering and engineering Management National Tsing Hua University Taiwan China Department of industrial engineering and Management National Taipei University of Technology Taiwan China School of engineering systems Queensland University of Technology Australia Department of Management Science National Chiao Tung University Taiwan China

The outage of a transformer in a power generation system will generally result in a shutdown of the entire system. Consequentially, large amounts of revenue are lost to the plant owner with a substantial negative impact on the civil community and industrial customers. This paper analyzes the current maintenance practices （i.e., an as-is process model） of a transformer manufacturing company, which provides maintenance services to power generation plants and reports the major weaknesses in current business practices. The maintenance weaknesses include isolated processes and paper based information communication. These inefficient processes result in service delays, cost increases, and inappropriate responses to customers＇ specific requests and complaints. To improve the efficiency and flexibility of the entire transformer maintenance service system, an e-integration approach is implemented with three key tasks. First, the current business processes are re-engineered to provide an improved （to-be） business model. Then, we replace paper based documentation methods with an electronic filing system for efficient and cost-effective information exchange. Afterward, the improved process model is implemented as an Internet based system to enhance the interactions among the transformer manufacturer, end-users, and service contractors for customized maintenance services. The case study demonstrates that implementing the e-integration approach increases the efficiency and effectiveness of the customized maintenance services.

关键词： Business Processes Reengineering (BPR) asset maintenance power industry after-sales services transformers engineering

Guaranteed cost control of networked control systems under limited communication capacity and variable sampling

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Journal of Central South University 2014年第3期21卷 978-986页

作者：刘英英褚云凯车伟伟 School of Information engineering Shenyang University Shenyang Institute of Automation Chinese Academy of Sciences Key Laboratory of manufacturing industrial Integrated Automation Shenyang University

The problem of guaranteed cost control for the networked control systems(NCSs) with time-varying delays, time-varying sampling intervals and signals quantization was investigated, wherein the physical plant was continuous-time one, and the control input was discrete-time one. By using an input delay approach and a sector bound method, the network induced delays, quantization parameter and sampling intervals were presented in one framework in the case of the state and the control input by quantized in a logarithmic form. A novel Lyapunov function with discontinuity, which took full advantages of the NCS characteristic information, was exploited. In addition, it was shown that Lyapunov function decreased at the jump instants. Furthermore, the Leibniz-Newton formula and free-weighting matrix methods were used to obtain the guaranteed cost controller design conditions which were dependent on the NCS characteristic information. A numerical example was used to illustrate the effectiveness of the proposed methods.

关键词： networked control systems (NCSS) quantization time-varying delays time-varying sampling guaranteed cost control

Stability analysis and stabilization of wireless networked control systems based on deadband control scheduling

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Journal of Central South University 2014年第11期21卷 4228-4235页

作者：刘英英褚云凯车伟伟刘意杨 School of Information engineering Shenyang University Shenyang Institute of Automation Chinese Academy of Sciences Key Laboratory of manufacturing industrial Integrated Automation (Shenyang University)

The stability analysis and stabilization problems of the wireless networked control systems(WNCSs) with signal transmission deadbands were considered. The deadbands were respectively set up at the sensor to the controller and the controller to the actor sides in the WNCS, which were used to reduce data transmission, furthermore, to decrease the network collision and node energy consumption. Under the consideration of time-varying delays and signal transmission deadbands, the model for the WNCS was presented. A novel Lyapunov functional which took full advantages of the network factors was exploited. Meanwhile, new stability analysis and stabilization conditions for the WNCS were proposed, which described the relationship of the delay bounds, the transmission deadband bounds and the system stability. Two examples were used to demonstrate the effectiveness of the proposed methods. The results show that the proposed approach can guarantee asymptotical stability of the system and reduce the data transmission effectively.

关键词： wireless networked control system transmission deadband time-varying delay stability analysis stabilization

Fabrication of integrated resistors in printed circuit boards

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Journal of Central South University 2011年第3期18卷 739-743页

作者：王守国陈清远 School of Information Science and Technology Northwest University Department of industrial and systems engineering The Hong Kong Polytechnic University

In order to utilize integrated passive technology in printed circuit boards （PCBs）, manufacturing processing for integrated resistors by lamination method was investigated. Integrated resistors fabricated from Ohmega technologies in the experiment were 1 408 pieces per panel with four different patterns A, B, C and D and four resistance values of 25, 50, 75 and 100 fL Six panel per batch and four batches were performed totally. The testing was done for 960 pieces of integrated resistors randomly selected with the same size. The value distribution ranges and the relative standard deviation （RSD） show that the scatter degree of the resistance decreases with the resistor size increasing and/or with the resistance increasing. Patterns D with resistance of 75 and 100% for four patterns have the resistance value variances less than 10%. Patterns C and D with resistance of 100 Ω have the manufacturing tolerance less than 10%. The process capabilities are from about 0.6 to 1.6 for the designed testing patterns, which shows that the integrated resistors fabricated have the potential to be used in multilayer PCBs in the future.

关键词： integrated resistors lamination method printed circuit boards integrated passive technology

Deep Neural Networks Based Approach for Battery Life Prediction

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Computers, Materials & Continua 2021年第11期69卷 2599-2615页

作者： Sweta Bhattacharya Praveen Kumar Reddy Maddikunta Iyapparaja Meenakshisundaram Thippa Reddy Gadekallu Sparsh Sharma Mohammed Alkahtani Mustufa Haider Abidi School of Information Technology and engineering Vellore Institute of TechnologyVelloreIndia Department of Computer Science and engineering Baba Ghulam Shah Badshah UniversityRajouriIndia industrial engineering Department College of EngineeringKing Saud UniversityRiyadhSaudi Arabia Raytheon Chair for systems engineering Advanced Manufacturing InstituteKing Saud UniversityRiyadhSaudi Arabia

The Internet of Things(IoT)and related applications have witnessed enormous growth since its *** diversity of connecting devices and relevant applications have enabled the use of IoT devices in every *** the applicability of these applications are predominant,battery life remains to be a major challenge for IoT devices,wherein unreliability and shortened life would make an IoT application completely *** this work,an optimized deep neural networks based model is used to predict the battery life of the IoT *** present study uses the Chicago Park Beach dataset collected from the publicly available data repository for the experimentation of the proposed *** dataset is pre-processed using the attribute mean technique eliminating the missing values and then One-Hot encoding technique is implemented to convert it to numerical *** processed data is normalized using the Standard Scaler *** Flame Optimization(MFO)Algorithm is then implemented for selecting the optimal features in the *** optimal features are finally fed into the DNN model and the results generated are evaluated against the stateof-the-art models,which justify the superiority of the proposed MFO-DNN model.

关键词： Battery life prediction moth flame optimization one-hot encoding standard scaler

Editorial for the Special Issue on Intelligent manufacturing

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engineering 2021年第6期7卷 704-705页

作者： Peigen Li Andrew Kusiak Liang Gao Weiming Shen The State Key Laboratory of Digital manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Department of industrial and systems engineering The University of IowaIowa CityIA 52242-1527USA

Intelligent manufacturing is the development trend of manufac-turing *** comprises the deep integration of new-genera-tion information and communication technologies(i.e.,fifth generation mobile networks(5G),artificial intelligence,the Indus-trial Internet,etc.)with advanced manufacturing technologies,covering the whole life cycle of a product,including design,pro-duction,logistics,services,and so *** it is largely based on automation and machine intelligence,humans play essential roles in intelligent manufacturing.

关键词： services Intelligent artificial

Laser surface treatment-introduced gradient nanostructured TiZrHfTaNb refractory high-entropy alloy with significantly enhanced wear resistance

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Journal of Materials Science & Technology 2022年第15期110卷 43-56页

作者： Jiasi Luo Wanting Sun Ranxi Duan Wenqing Yang K.C.Chan Fuzeng Ren Xu-Sheng Yang Department of industrial and systems engineering Advanced Manufacturing Technology Research CentreThe Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Department of Materials Science and engineering Southern University of Science and TechnologyShenzhen 518055China The Hong Kong Polytechnic University Shenzhen Research Institute Shenzhen 518060China

Heterogeneous gradient nanostructured metals have been shown to achieve the strength-ductility synergy, thus potentially possessing the enhanced tribological performance in comparison with their homogeneous nanograined counterparts. In this work, a facile laser surface remelting-based surface treatment technique is developed to fabricate a gradient nanostructured layer on a TiZrHfTaNb refractory highentropy alloy. The characterization of the microstructural evolution along the depth direction from the matrix to the topmost surface layer shows that the average grain size in the ~100 μm-thick gradient nanostructured layer is dramatically refined from the original ~200 μm to only ~8 nm in the top surface layer. The microhardness is therefore gradually increased from ~240 HV in matrix to ~650 HV in the topmost surface layer, approximately 2.7 times. Noticeably, the original coarse-grained single-phase bodycentered-cubic TiZrHfTaNb refractory high-entropy alloy is gradually decomposed into TiNb-rich bodycentered-cubic phase, TaNb-rich body-centered-cubic phase, ZrHf-rich hexagonal-close-packed phase and TiZr Hf-rich face-centered-cubic phase with gradient distribution in grain size along the depth direction during the gradient refinement process. As a result, the novel laser surface treatment-introduced gradient nanostructured TiZrHfTaNb refractory high-entropy alloy demonstrates the significantly improved wear resistance, with the wear rate reducing markedly by an order of magnitude, as compared with the as-cast one. The decomposed multi-phases and gradient nanostructures should account for the enhanced wear resistance. Our findings provide new insights into the refinement mechanisms of the laser-treated refractory high-entropy alloys and broaden their potential applications via heterogeneous gradient nanostructure engineering.

关键词： Laser surface treatment Refractory high-entropy alloy Gradient nanostructure Wear resistance High-resolution transmission electron microscopy