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Rotating consensus of multi-agent systems without relative velocity measurement

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Chinese Physics B 2011年第9期20卷 148-151页

作者：陈小平徐红兵班永鑫 Institute of Astronautics and Aeronautics University of Electronic Science and Technology of China School of Automation University of Electronic Science and Technology of China Beijing Hang Xing Machinary manufacturing company

We study the rotating consensus of multi-agent systems without the relative velocity measurement in this paper. A new protocol is proposed. Then we use the theory of the complex system combined with the function continuity to derive a condition, under which all agents finally reach the rotating consensus. Finally, a numerical example is provided to illustrate our theoretical results.

关键词： rotating consensus multi-agent systems complex systems

A tip clearance prediction model for multistage rotors and stators in aero-engines

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Chinese Journal of Aeronautics 2021年第2期34卷 343-357页

作者： Huibin SUN Jing WANG Kai CHEN Huateng XIA Xin FENG Zhiyong CHANG Key Laboratory of High Performance manufacturing for Aero Engine Ministry of Industry and Information TechnologyNorthwestern Poly technical UniversityXi'an 710072China AECC South Industry company Limited Zhuzhou 412002China

Tip clearances of multistage rotors and stators greatly affect aero-engines’ aerodynamic efficiency, stability and safety. The inevitable machining and assembly errors, as well as the complicated error propagation mechanism, cause overproof or non-uniform tip clearances. However, it is generally accepted that tip clearances are difficult to predict, even under assembly state. In this paper, a tip clearance prediction model is proposed based on measured error data. Some 3 D error propagation sub-models, regarding rotors, supports and casings, are built and combined. The complex error coupling relationship is uncovered using mathematical methods. Rotor and stator tip clearances are predicted and analyzed in different phase angles. The maximum, minimum and average tip clearances can be calculated. The proposed model is implemented by a computer program,and a case study illustrates its performance and verifies its feasibility. The results can be referred by engineers in assembly quality judgement and decision-making.

关键词： Tip clearance Prediction Error propagation model Rotor and stator Aero-engine Assembly

Seasonal Influence on the Ambient Air Quality in Al Jahra City for Year 2010

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Journal of Environmental Protection 2012年第12期3卷 1711-1718页

作者： Raslan Alenezi Bader Al-Anzi Abdallah Abusam Aamir Ashfaque Department of Chemical Engineering College of Technological Studies Public Authority Applied Education and Training Adailiya Kuwait Department of Environment Technology and Management College for Women Kuwait University Kuwait City Kuwait gulf paper manufacturing company Fahaheel Kuwait Water Technologies Department Water Resources Division Kuwait Institute for Scientific Research Safat Kuwait

Eight primary criteria air contaminants were measured continuously for the year 2010 to evaluate ambient air quality in Al Jahra, which is one of the oldest and busiest cities in the state of Kuwait. The state of the art instrumentation was used to record the pollutants concentration to ppb levels maintaining quality control and quality assurance. Hourly base data for Non-Methane Hydrocarons (NM-HC), CH4, CO, CO2, O3, SO2, NO2and Particulate Matter (PM10) were analyzed for year 2010. Meteorological parameters contributing to air pollution, such as (temperature, solar intensity, wind speed and direction) have also been considered. The effect of winter and summer seasonal changes on pollutant concentration levels were analyzed to identify the most probable sources for the application of the futuristic mitigation methods for pollution abatement. The obtained results consistently suggest that the foregoing pollutant concentration levels are higher in winter than summer due to poor dispersion and shallow inversion layer with the exception of O3, CO2and PM10. However, all of the pollutant concentrations are below the allowable standards limits except for NM-HC.

关键词： Pollutants Al Jahra Seasonal Changes Monitoring Station

Development and Implementation of an Advanced Planning & Scheduling (APS) System for Semiconductor Backend Assembly

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厦门大学学报（自然科学版） 2002年第S1期41卷 189-190页

作者： T J Chua T X Cai F Y Wang William Liu X F Yin W J Yan J P Zhu Joanne Lam Gintic Institute of manufacturing Technology Gintic Institute of Manufacturing TechnologyGintic Institute of Manufacturing TechnologyGintic Institute of Manufacturing TechnologyGintic Institute of Manufacturing TechnologyGintic Institute of Manufacturing TechnologyGintic Institute of Manufacturing TechnologyGintic Institute of Manufacturing Technology SingaporeSingaporeSingaporeSingaporeSingaporeSingaporeSingaporeSingapore

In this paper, the design, customization and implem en tation of an integrated Advanced Planning and Scheduling (APS) system for a Semi conductor Backend Assembly environment is described. The company is one of the w orldwide market leaders in semiconductor packaging technology. The project was d riven by the company’s quest to achieve a competitive edge as a manufacturing po werhouse by providing the shortest possible cycle time with a high degree of fle xibility through the application of Computer Integrated manufacturing (CIM) tech nology. Gintic was responsible for the Planning & Scheduling functions through o ur APS tool kit, which is called Gintic Scheduling System (GSS). Our APS system is to be integrated with the other two key software systems, namely, the Enterpr ise Resource Planning (ERP) and manufacturing Execution System (MES), with the C IM framework. The project was divided into four major execution phases. Phase One activities w ere focused on the gathering and analysis of the end users requirements in order to establish the ’As-Is’ situation and the wish list & the expectation of the ’To-Be’ system. Planning and Scheduling prototypes were built using GSS to iden tify the functionality gap between the existing GSS system and the ’To-Be’ mode l, in order to determine the customization effort needed. The project team perfo rmed detailed system analysis, design and development of the ’To-Be’ system dur ing Phase Two of the project. There are a total of four planning and scheduling modules, including Capacity Planning (CP), Daily Lot Release (DLR), Daily Produc tion Scheduling (DPS) and Dynamic Operation Scheduling (DOS). The detailed desig n specifications of each of the features and functionality were confirmed and ac cepted by the end users before the commencement of the development effort. The c ompleted and tested modules were delivered in stages for testing and acceptance by the end user during the Phase Three of the project. Pilot product line was

关键词： integrated planning scheduling semiconductor b ackend assembly

Experimental Study on the Erosion of Pipelines under Different Load Conditions

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Fluid Dynamics & Materials Processing 2022年第2期18卷 233-241页

作者： Xuewen Cao Ni Xiong Jian Li Zhenqiang Xie Xuerui Zang Jiang Bian Shandong Key Laboratory of Oil&Gas Storage and Transportation Safety China University of Petroleum(East China)Qingdao266580China gulf Region company of China Petroleum Engineering&Construction Co. Ltd.Beijing100120China

The influence of the material stress state induced by internal and external forces on the erosion rate of pipelines has rarely been investigated in the *** order to fill this gap,using a tensile tester machine,a two–phase gas–solid particles jet erosion test was carried out considering a 316L stainless steel under different tensile stresses and different erosion *** results show that:1)In the elastic range,with the increase of stress,the erosion rate manifests a rising trend;2)In the metal plastic range,the increase of stress leads to a decrease of the erosion rate;3)The erosion rate at a small erosion angle is more sensitive to the increment of *** present research demonstrates that the combined effect of erosion and material internal stress can contribute to determine the effective resistance of the vulnerable parts of piping systems(such as elbows or similar components).

关键词： Pipeline load solid particles erosion

Nonlinear Equations Solving with Intelligent Optimization Algorithms: A Survey

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Complex System Modeling and Simulation 2021年第1期1卷 15-32页

作者： Wenyin Gong Zuowen Liao Xianyan Mi Ling Wang Yuanyuan Guo School of Computer Science China University of GeosciencesWuhan 430074China Development Research Center Beibu Gulf UniversityQinzhou 535000China College of Economics and Management Beibu Gulf UniversityQinzhou 535000China Department of Automation Tsinghua UniversityBeijing 100084China Cvent company FrederictonE3B 5H8Canada.

Nonlinear Equations(NEs),which may usually have multiple roots,are ubiquitous in diverse *** of the main purposes of solving NEs is to locate as many roots as possible simultaneously in a single run,however,it is a difficult and challenging task in numerical *** recent years,Intelligent Optimization Algorithms(IOAs)have shown to be particularly effective in solving *** paper provides a comprehensive survey on IOAs that have been exploited to locate multiple roots of *** paper first revisits the fundamental definition of NEs and reviews the most recent development of the transformation ***,solving NEs with IOAs is reviewed,followed by the benchmark functions and the performance comparison of several state-of-the-art ***,this paper points out the challenges and some possible open issues for solving NEs.

关键词： Nonlinear Equations(NEs) Intelligent Optimization Algorithms(IOA) multiple roots location transformation techniques diversity preservation

Connecting supplier and DoD blockchains for transparent part tracking

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Blockchain(Research and Applications) 2021年第3期2卷 17-30页

作者： Francis Asuncion Adam Brinckman Dwayne Cole Jeffrey Curtis Matt Davis Timothy Dunlevy Calvin Farmer Andrew Harrison Daniel P.Johnson Joshua Joyce Chris Klubertanz Jonathan Lane John Martin Jarek Nabrzyski Joel Neidig Deysi Olivares Gregory Robinson Gabriel Rodriguez Chris Root Karen Rowand Al Salour Jeff Score David Scott Ian Taylor Chandler Thompson Huy Truong Xiqun Wang Dale Warren NAVAIR USA SIMBA Chain PlymouthIN46563USA Center for Research Computing University of Notre DameNotre DameIN46556USA Indiana Technology and manufacturing Companies(ITAMCO) PlymouthIN46563USA Boeing company USA Naval Systems Inc.USA

Blockchains have been around for more than ten years,and since 2015,a plethora of systems have been launched to target more flexible use *** recently,several enterprise blockchain systems,such as Consensys Quorum and Hyperledger Fabric,have been launched to make blockchain simpler to apply in complex organizational *** this paper,we identify a specific Department of Defense use case,extrapolate requirements,and perform a thorough assessment of the different layers of the blockchain stack to identify the existing state of the art and undertake a gap analysis of the technology for this *** describe a platform that meets many of these challenges and show how we architected,designed,and implemented a solution for this use case for deployment at *** solution connects transactions from two separate blockchain systems,Consensys Quorum and Hyperledger Fabric,by using a graph-based approach that preserves privacy while enabling full transparency across the military and supplier networks.

关键词： Blockchain Smart contracts Supply chain Department of defense(DoD) GraphQL Enterprise blockchain systems

Simulation-based manufacturing System Modeling

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Journal of Donghua University(English Edition) 2003年第1期20卷 27-31页

作者：卫东金烨范秀敏严隽琪 Institute of Computer Integrated manufacturing Shanghai Jiaotong University 200030

In recent years, computer simulation appears to be very advantageous technique for researching the resource-constrained manufacturing system. This paper presents an object-oriented simulation modeling method, which combines the merits of traditional methods such as IDEF0 and Petri Net. In this paper, a four-layer-one-angel hierarchical modeling framework based on OOP is defined. And the modeling description of these layers is expounded, such as: hybrid production control modeling and human resource dispatch modeling. To validate the modeling method, a case study of an auto-product line in a motor manufacturing company has been carried out.

关键词： Discrete event simulation Automotive Production Line Hybrid-control Work-force resource Management.

A Framework to Support Agility Strategy Formulation

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厦门大学学报（自然科学版） 2002年第S1期41卷 258-259页

作者： Z Zhang Exeter Centre for manufacturing and Enterprise Competitiveness (XMEC)

In the last decade, turbulent times and uncertainti es in the business environment have made ground for a new business era, and "chang e" has become a major characteristic of the new era. This has resulted in tirele ss evolution of business systems and the creation of new manufacturing and manag ement philosophies. Agile manufacturing (AM) is a step forward in generation of new means for better performance and success of business, and in practice is a s trategic approach to manufacturing by considering the new conditions of the business environment. This paper discusses the concepts and development of a met hodology to achieve agility in manufacturing organisations. Following an introdu ction of the subject of agility, a discussion of the methodology and practical t ools to support the implementation of the methodology, including metrics for the assessment of agility drivers, capability and performance are given. Aspects of the tools are tested in an aerospace company.

关键词： A Framework to Support Agility Strategy Formulation