This article briefly discusses the theoretical basis and overall goals of energy conservation in the steel manufacturing process system.It is proposed that in the process of implementing system energy conservation,it ...This article briefly discusses the theoretical basis and overall goals of energy conservation in the steel manufacturing process system.It is proposed that in the process of implementing system energy conservation,it is necessary to fully recognize and utilize the characteristics and functional advantages of the steel manufacturing process,pay more attention to energy quality,firmly grasp the overall goal of system optimization,focus on the integrated optimization of gas,steam,and waste heat systems,and propose the idea of constructing a"steel chemi-cal gas electricity heating cooling multi generation system".Based on practice,the main principles,models,and effects of implementing systematic energy conservation in steel enterprises have been proposed.展开更多
Product and manufacturing process developments are knowledge intensive. For rapid product developments in today′s competitive global marketplace, we need tools to facilitate the effective utilization of critical des...Product and manufacturing process developments are knowledge intensive. For rapid product developments in today′s competitive global marketplace, we need tools to facilitate the effective utilization of critical design and manufacturing knowledge obtained during the previous product developments. The Internet technology has very rapidly evolved over past few years. The web is being increasingly used to support various activities of the pro duct development process. Java is a programming language that is highly tuned for the web environment. This paper is concerned with providing the solution of web based manufacturing process development. The architecture of web based application and the implementation of web based manufacturing process developer are discussed.展开更多
Against the realistic background of excess production capacity, product structure imbalance, and high material and energy consumption in steel enterprises, the implementation of operation optimization for the steel ma...Against the realistic background of excess production capacity, product structure imbalance, and high material and energy consumption in steel enterprises, the implementation of operation optimization for the steel manufacturing process is essential to reduce the production cost, increase the production or energy efficiency, and improve production management. In this study, the operation optimization problem of the steel manufacturing process, which needed to go through a complex production organization from customers' orders to workshop production, was analyzed. The existing research on the operation optimization techniques, including process simulation, production planning, production scheduling, interface scheduling, and scheduling of auxiliary equipment, was reviewed. The literature review reveals that, although considerable research has been conducted to optimize the operation of steel production, these techniques are usually independent and unsystematic.Therefore, the future work related to operation optimization of the steel manufacturing process based on the integration of multi technologies and the intersection of multi disciplines were summarized.展开更多
From the viewpoint of systems energy conservation, the influences of material flow on its energy consumption in a steel manufacturing process is an important subject. The quantitative analysis of the relationship betw...From the viewpoint of systems energy conservation, the influences of material flow on its energy consumption in a steel manufacturing process is an important subject. The quantitative analysis of the relationship between material flow and the energy intensity is useful to save energy in steel industry. Based on the concept of standard material flow diagram, all possible situations of ferric material flow in steel manufacturing process are analyzed. The expressions of the influence of material flow deviated from standard material flow diagram on energy consumption are put forward.展开更多
The standard material flow diagram in steel manufacturing process was proposed to analyze the influences of various material flows on environmental load of 1tof final product.Two influence factors and reducing measure...The standard material flow diagram in steel manufacturing process was proposed to analyze the influences of various material flows on environmental load of 1tof final product.Two influence factors and reducing measures of environmental load were pointed out.The environmental load was appraised for a typical technological process in a Chinese steel plant.展开更多
In this study,the best manufacturing process will be selected to build an automotive crash box using green oil palm natural fibre-reinforced polyurethane composite materials.This paper introduces an approach consist o...In this study,the best manufacturing process will be selected to build an automotive crash box using green oil palm natural fibre-reinforced polyurethane composite materials.This paper introduces an approach consist of technical aspects(T),the economic point of view(E)and availability(A),and it’s also called as TEA requirement.This approach was developed with the goal of assisting the design engineer in the selection of the best manufacturing process during the design phase at the criteria selection stage.In this study,the TEA requirement will integrate with the analytical hierarchy process(AHP)to assist decision makers or manufacturing engineers in determining the most appropriate manufacturing process to be employed in the manufacture of a composite automotive crash box(ACB)at the early stage of the product development process.It is obvious that a major challenge in the manufacturing selection process is lack of information regarding manufacturing of ACB using natural fibre composite(NFC).There have been no previous studies that examined ranking manufacturability processes in terms of their suitability.Therefore,the TEA-AHP hybrid method was introduced to provide unprejudiced criteria-ranking selection prior to evaluation of pairwise comparisons.At the end of this study,the pulforming process was selected as the best manufacturing process for fabrication of the ACB structural component.展开更多
This paper reports the evolution of textile structure and mechanical properties of vascular prosthesis in the level of the whole prosthesis and the constituent filaments with respect to the manufacturing process. The ...This paper reports the evolution of textile structure and mechanical properties of vascular prosthesis in the level of the whole prosthesis and the constituent filaments with respect to the manufacturing process. The tubular wall of the prosthesis is divided circumferentially into three zones; basic line (BL), remeshing line ( RL) and guide line ( GL). Some heterogeneity has been observed on the tubular wall in terms of stitch structure of the prosthesis and linear density of the constituent filaments. The breaking position of the prosthesis under circumferential tensile localizes preferentially in remeshing line that is the weakest zone by warp knitting with double needle bed. Furthermore, the statistical differences of the mechanical properties of the filaments of zone RL, GL and BL have been confirmed too. It is predictable that the deterioration of prosthesis, under physiological loads (periodical pulse blood pressure etc.), could happen firstly in the weaker zone in vivo.展开更多
Green manufacturing is a mode to realize environmental friendliness by considering the environmental impact and energy consumption in manufacturing process.In order to make an environmental friendly assessment for man...Green manufacturing is a mode to realize environmental friendliness by considering the environmental impact and energy consumption in manufacturing process.In order to make an environmental friendly assessment for manufacturing process,a multi-criteria decision making( MCDM) model combined with fuzzy analytic hierarchy process( FAHP) and fuzzy technique for order preference by similarity to ideal solution( FTOPSIS) is proposed in this work.The environmental and resource criteria and manufacturing process objects are identified as the first step.Then,the weights of the criteria are calculated by FAHP.Finally,based on experts' evaluation using fuzzy words,the manufacturing process objects are ranked by FTOPSIS.The proposed methodology is applied to a gear shaft manufacturing.The sensitivity analysis and comparisons are implemented to prove its robustness and effectiveness for the ecofriendly assessment for process objects.展开更多
The main characteristics, applications, the emphases of manufacturing process are introduced, and the research of new product of rigid-flex Printed Circuit Board (PCB) is also described. In particular, the plasma de...The main characteristics, applications, the emphases of manufacturing process are introduced, and the research of new product of rigid-flex Printed Circuit Board (PCB) is also described. In particular, the plasma desmear process, which is the crucial problems of manufacturing process, is discussed in detail. Samsung 4-layer rigid-flex PCB has been developed successfully, and the qualification rate reaches to 89.4%.展开更多
In order to investigate the effect of the relative motion of nano CaCO_(3)reinforced bamboo pulp fiber(BPF)/HDPE composite components on the mechanical performance,a comparative study was performed.BPF was treated by ...In order to investigate the effect of the relative motion of nano CaCO_(3)reinforced bamboo pulp fiber(BPF)/HDPE composite components on the mechanical performance,a comparative study was performed.BPF was treated by nano CaCO_(3)blending(BM)and impregnation modification(IM)technology.The composites were produced using hot press(HPMP),extrusion(EMP)and injection molding process(IMP).The physical morphology of BPF was similar at different manufacturing processes.Compared to the samples manufactured by HPMP,a decrease in the(specific)flexural strength of BPF/HDPE composites and an increase in those of composites treated by nano CaCO_(3)manufactured by EMP and IMP were observed.The injection molded composites exhibited the best values in the(specific)impact strength,(specific)tensile properties.IM had a greater effect on the rheological behavior of the composites than BM,and nano CaCO_(3)treatment most effectively affected the performance of the extrusion molded composites.展开更多
Compliant micromechanisms(CMMs)acquire mobility from the deflection of elastic members and have been proven to be robust by millions of silicon MEMS devices.However,the limited deflection of silicon impedes the realiz...Compliant micromechanisms(CMMs)acquire mobility from the deflection of elastic members and have been proven to be robust by millions of silicon MEMS devices.However,the limited deflection of silicon impedes the realization of more sophisticated CMMs,which often require larger deflections.Recently,some novel manufacturing processes have emerged but are not well known by the community.In this paper,the realization of CMMs is reviewed,aiming to provide help to mechanical designers to quickly find the proper realization method for their CMM designs.To this end,the literature surveyed was classified and statistically analyzed,and representative processes were summarized individually to reflect the state of the art of CMM manufacturing.Furthermore,the features of each process were collected into tables to facilitate the reference of readers,and the guidelines for process selection were discussed.The review results indicate that,even though the silicon process remains dominant,great progress has been made in the development of polymer-related and composite-related processes,such as micromolding,SU-8 process,laser ablation,3D printing,and the CNT frameworking.These processes result in constituent materials with a lower Young’s modulus and larger maximum allowable strain than silicon,and therefore allow larger deflection.The geometrical capabilities(e.g.,aspect ratio)of the realization methods should also be considered,because different types of CMMs have different requirements.We conclude that the SU-8 process,3D printing,and carbon nanotube frameworking will play more important roles in the future owing to their excellent comprehensive capabilities.展开更多
Simulation technique is an efficient approach to realize the planning and scheduling of manufacturing process of products. An appropriate and efficient manufacturing process model is the basis and key of manufacturing...Simulation technique is an efficient approach to realize the planning and scheduling of manufacturing process of products. An appropriate and efficient manufacturing process model is the basis and key of manufacturing process simulation. By analyzing the features of large-sized and complex products, a method of manufacturing process modeling based on activity network is presented and a mapping algorithm of translating BOM/BOP into the manufacturing process model is designed in detail.展开更多
Steels are widely used as structural materials,making them essential for supporting our lives and industries.However,further improving the comprehensive properties of steel through traditional trial-and-error methods ...Steels are widely used as structural materials,making them essential for supporting our lives and industries.However,further improving the comprehensive properties of steel through traditional trial-and-error methods becomes challenging due to the continuous development and numerous processing parameters involved in steel production.To address this challenge,the application of machine learning methods becomes crucial in establishing complex relationships between manufacturing processes and steel performance.This review begins with a general overview of machine learning methods and subsequently introduces various performance predictions in steel materials.The classification of performance pre-diction was used to assess the current application of machine learning model-assisted design.Several important issues,such as data source and characteristics,intermediate features,algorithm optimization,key feature analysis,and the role of environmental factors,were summarized and analyzed.These insights will be beneficial and enlightening to future research endeavors in this field.展开更多
Zero defection manufacturing (ZDM) is the pursuit of the manufacturing industry. However, there is a lack of the implementation method of ZDM in the multi-stage manufacturing process (MMP). Implementing ZDM and contro...Zero defection manufacturing (ZDM) is the pursuit of the manufacturing industry. However, there is a lack of the implementation method of ZDM in the multi-stage manufacturing process (MMP). Implementing ZDM and controlling product quality in MMP remains an urgent problem in intelligent manufacturing. A novel predict-prevention quality control method in MMP towards ZDM is proposed, including quality characteristics monitoring, key quality characteristics prediction, and assembly quality optimization. The stability of the quality characteristics is detected by analyzing the distribution of quality characteristics. By considering the correlations between different quality characteristics, a deep supervised long-short term memory (SLSTM) prediction network is built for time series prediction of quality characteristics. A long-short term memory-genetic algorithm (LSTM-GA) network is proposed to optimize the assembly quality. By utilizing the proposed quality control method in MMP, unqualified products can be avoided, and ZDM of MMP is implemented. Extensive empirical evaluations on the MMP of compressors validate the applicability and practicability of the proposed method.展开更多
Northern Anhui was an important region for diverse bronze culture convergence and extensive metal resource circulation in the Pre-Qin Period.In this paper,metallographic microstructure analysis,chemical composition an...Northern Anhui was an important region for diverse bronze culture convergence and extensive metal resource circulation in the Pre-Qin Period.In this paper,metallographic microstructure analysis,chemical composition analysis,and lead isotope ratio analysis were conducted on 12 samples of 6 Warring States Period(476–221 BCE)bronze vessels excavated from Chutai Cemetery M1,Fuyang,Anhui Province,revealing the integrated application of diversified manufacturing processes,such as casting,forging,cold working,and welding and multiple metal minerals.The analytical results showed that 2 Ding vessels(鼎)were made by casting,and 2 He vessels(盒)and 2 Dui vessels(敦)were made by forging followed by cold working.These two types of bronze vessels made by different manufacturing processes have significantly distinct alloy ratios and mineral sources,among which the Cu and Sn contents of the 2 cast bronze vessels are lower and the Pb content is higher,while the Cu and Sn contents of the 4 forged bronze vessels are higher and the Pb content is lower.The lead minerals of the two types of bronze vessels might come from Western Henan and the middle and lower reaches of the Yangtze River,respectively.In addition,the 3 pieces of solder used to weld bronze vessels were all made of pure Sn,their metal minerals should come from the densely distributed area of tin ore in Southern China,and Sn solders were mainly discovered in the Chu culture area during the Eastern Zhou Period.展开更多
Due to space availability limitations and high land costs,there is an increasing development of multi-floor manufacturing(MFM)systems in urban and industrial areas.The problem of coordination in a multi-floor manufact...Due to space availability limitations and high land costs,there is an increasing development of multi-floor manufacturing(MFM)systems in urban and industrial areas.The problem of coordination in a multi-floor manufacturing process,in the Ramadge Wonham framework,is introduced.The manufacturing chain of each floor and the elevator system are modeled in the form of finite deterministic automata.The models of the multi-floor manufacturing process are parametric with respect to the number of floors and the number of manufacturing machines on each floor.The coordination desired performance is formulated in the form of desired regular languages in analytic forms.The languages are realized by appropriate supervisors in the form of finite deterministic automata.The models of the supervisors are also parametric with respect to the number of floors and the number of manufacturing machines on each floor.The total control of the coordination of the multi-floor manufacturing process is accomplished via a modular supervisory control architecture.The complexity of the supervisors as well as the complexity of the total modular supervisory architecture are determined in analytic forms with respect to the number of floors and the number of manufacturing machines on each floor.The special case of a two floor manufacturing process is presented as an illustrative example.展开更多
The prognostics health management(PHM)fromthe systematic viewis critical to the healthy continuous operation of processmanufacturing systems(PMS),with different kinds of dynamic interference events.This paper proposes...The prognostics health management(PHM)fromthe systematic viewis critical to the healthy continuous operation of processmanufacturing systems(PMS),with different kinds of dynamic interference events.This paper proposes a three leveled digital twinmodel for the systematic PHMof PMSs.The unit-leveled digital twinmodel of each basic device unit of PMSs is constructed based on edge computing,which can provide real-time monitoring and analysis of the device status.The station-leveled digital twin models in the PMSs are designed to optimize and control the process parameters,which are deployed for the manufacturing execution on the fog server.The shop-leveled digital twin maintenancemodel is designed for production planning,which gives production instructions fromthe private industrial cloud server.To cope with the dynamic disturbances of a PMS,a big data-driven framework is proposed to control the three-level digital twin models,which contains indicator prediction,influence evaluation,and decisionmaking.Finally,a case study with a real chemical fiber system is introduced to illustrate the effectiveness of the digital twin model with edge-fog-cloud computing for the systematic PHM of PMSs.The result demonstrates that the three-leveled digital twin model for the systematic PHM in PMSs works well in the system’s respects.展开更多
Accessibility is a kind of important design feature of products,and accessibility analysis has been acknowledged as a powerful tool for solving computational manufacturing problems arising from different manufacturing...Accessibility is a kind of important design feature of products,and accessibility analysis has been acknowledged as a powerful tool for solving computational manufacturing problems arising from different manufacturing processes.After exploring the relations among approachability,accessibility and visibility,a general method for accessibility analysis using visibility cones (VC) is proposed.With the definition of VC of a point,three kinds of visibility of a feature,namely complete visibility cone (CVC),partial visibility cone (PVC) and local visibility cone (LVC),are defined.A novel approach to computing VCs is formulated by identifying C-obstacles in the C-space,for which a general and efficient algorithm is proposed and implemented by making use of visibility culling.Lastly,we discuss briefly how to realize accessibility analysis in numerically controlled (NC) machining planning,coordinate measuring machines (CMMs) inspection planning and assembly sequence planning with the proposed methods.展开更多
Theoretical minimum and actual specific energy consumptions (SEC) of typical manufacturing process (SMP) were studied. Firstly, a process division of a typical SMP in question was conducted with the theory of SEC ...Theoretical minimum and actual specific energy consumptions (SEC) of typical manufacturing process (SMP) were studied. Firstly, a process division of a typical SMP in question was conducted with the theory of SEC analysis. Secondly, an exergy analysis model of a subsystem consisting of several parallel processes and a SEC analysis model of SMP were developed. And finally, based on the analysis models, the SEC of SMP was analyzed by means of the statistical significance. The results show that the SEC of typical SMP comprises the theoretical minimum SEC and the additional SEC derived from the irreversibility~ and the SMP has a theoretical minimum SEC of 6.74 GJ/t and an additional SEC of 19.32 GJ/t, which account for 25.88% and 74.12% of the actual SEC, respectively.展开更多
文摘This article briefly discusses the theoretical basis and overall goals of energy conservation in the steel manufacturing process system.It is proposed that in the process of implementing system energy conservation,it is necessary to fully recognize and utilize the characteristics and functional advantages of the steel manufacturing process,pay more attention to energy quality,firmly grasp the overall goal of system optimization,focus on the integrated optimization of gas,steam,and waste heat systems,and propose the idea of constructing a"steel chemi-cal gas electricity heating cooling multi generation system".Based on practice,the main principles,models,and effects of implementing systematic energy conservation in steel enterprises have been proposed.
文摘Product and manufacturing process developments are knowledge intensive. For rapid product developments in today′s competitive global marketplace, we need tools to facilitate the effective utilization of critical design and manufacturing knowledge obtained during the previous product developments. The Internet technology has very rapidly evolved over past few years. The web is being increasingly used to support various activities of the pro duct development process. Java is a programming language that is highly tuned for the web environment. This paper is concerned with providing the solution of web based manufacturing process development. The architecture of web based application and the implementation of web based manufacturing process developer are discussed.
基金financially supported by the National Natural Science Foundation of China (No.51734004)the National Key Research and Development Program of China (No.2017YFB0304005)the National Natural Science Foundation of China (No.51474044)。
文摘Against the realistic background of excess production capacity, product structure imbalance, and high material and energy consumption in steel enterprises, the implementation of operation optimization for the steel manufacturing process is essential to reduce the production cost, increase the production or energy efficiency, and improve production management. In this study, the operation optimization problem of the steel manufacturing process, which needed to go through a complex production organization from customers' orders to workshop production, was analyzed. The existing research on the operation optimization techniques, including process simulation, production planning, production scheduling, interface scheduling, and scheduling of auxiliary equipment, was reviewed. The literature review reveals that, although considerable research has been conducted to optimize the operation of steel production, these techniques are usually independent and unsystematic.Therefore, the future work related to operation optimization of the steel manufacturing process based on the integration of multi technologies and the intersection of multi disciplines were summarized.
基金Item Sponsored by National Basic Research Programof China (200002600)
文摘From the viewpoint of systems energy conservation, the influences of material flow on its energy consumption in a steel manufacturing process is an important subject. The quantitative analysis of the relationship between material flow and the energy intensity is useful to save energy in steel industry. Based on the concept of standard material flow diagram, all possible situations of ferric material flow in steel manufacturing process are analyzed. The expressions of the influence of material flow deviated from standard material flow diagram on energy consumption are put forward.
基金Sponsored by National Natural Science Foundation of China(50334020)
文摘The standard material flow diagram in steel manufacturing process was proposed to analyze the influences of various material flows on environmental load of 1tof final product.Two influence factors and reducing measures of environmental load were pointed out.The environmental load was appraised for a typical technological process in a Chinese steel plant.
文摘In this study,the best manufacturing process will be selected to build an automotive crash box using green oil palm natural fibre-reinforced polyurethane composite materials.This paper introduces an approach consist of technical aspects(T),the economic point of view(E)and availability(A),and it’s also called as TEA requirement.This approach was developed with the goal of assisting the design engineer in the selection of the best manufacturing process during the design phase at the criteria selection stage.In this study,the TEA requirement will integrate with the analytical hierarchy process(AHP)to assist decision makers or manufacturing engineers in determining the most appropriate manufacturing process to be employed in the manufacture of a composite automotive crash box(ACB)at the early stage of the product development process.It is obvious that a major challenge in the manufacturing selection process is lack of information regarding manufacturing of ACB using natural fibre composite(NFC).There have been no previous studies that examined ranking manufacturability processes in terms of their suitability.Therefore,the TEA-AHP hybrid method was introduced to provide unprejudiced criteria-ranking selection prior to evaluation of pairwise comparisons.At the end of this study,the pulforming process was selected as the best manufacturing process for fabrication of the ACB structural component.
基金Funded by the Shanghai Post Doctoral Foundation Overseas Returned Scholars' Foundation of Education Ministry the Shanghai Key Discipline Project
文摘This paper reports the evolution of textile structure and mechanical properties of vascular prosthesis in the level of the whole prosthesis and the constituent filaments with respect to the manufacturing process. The tubular wall of the prosthesis is divided circumferentially into three zones; basic line (BL), remeshing line ( RL) and guide line ( GL). Some heterogeneity has been observed on the tubular wall in terms of stitch structure of the prosthesis and linear density of the constituent filaments. The breaking position of the prosthesis under circumferential tensile localizes preferentially in remeshing line that is the weakest zone by warp knitting with double needle bed. Furthermore, the statistical differences of the mechanical properties of the filaments of zone RL, GL and BL have been confirmed too. It is predictable that the deterioration of prosthesis, under physiological loads (periodical pulse blood pressure etc.), could happen firstly in the weaker zone in vivo.
基金National Natural Science Foundation of China(No.51475459)the Priority Academic Program Development of Jiangsu Higher Education Institutions of China(No.PAPD)
文摘Green manufacturing is a mode to realize environmental friendliness by considering the environmental impact and energy consumption in manufacturing process.In order to make an environmental friendly assessment for manufacturing process,a multi-criteria decision making( MCDM) model combined with fuzzy analytic hierarchy process( FAHP) and fuzzy technique for order preference by similarity to ideal solution( FTOPSIS) is proposed in this work.The environmental and resource criteria and manufacturing process objects are identified as the first step.Then,the weights of the criteria are calculated by FAHP.Finally,based on experts' evaluation using fuzzy words,the manufacturing process objects are ranked by FTOPSIS.The proposed methodology is applied to a gear shaft manufacturing.The sensitivity analysis and comparisons are implemented to prove its robustness and effectiveness for the ecofriendly assessment for process objects.
文摘The main characteristics, applications, the emphases of manufacturing process are introduced, and the research of new product of rigid-flex Printed Circuit Board (PCB) is also described. In particular, the plasma desmear process, which is the crucial problems of manufacturing process, is discussed in detail. Samsung 4-layer rigid-flex PCB has been developed successfully, and the qualification rate reaches to 89.4%.
基金This study is financially supported by the Basic Research Operating Expenses Program of International Centre for Bamboo and Rattan(1632021002).
文摘In order to investigate the effect of the relative motion of nano CaCO_(3)reinforced bamboo pulp fiber(BPF)/HDPE composite components on the mechanical performance,a comparative study was performed.BPF was treated by nano CaCO_(3)blending(BM)and impregnation modification(IM)technology.The composites were produced using hot press(HPMP),extrusion(EMP)and injection molding process(IMP).The physical morphology of BPF was similar at different manufacturing processes.Compared to the samples manufactured by HPMP,a decrease in the(specific)flexural strength of BPF/HDPE composites and an increase in those of composites treated by nano CaCO_(3)manufactured by EMP and IMP were observed.The injection molded composites exhibited the best values in the(specific)impact strength,(specific)tensile properties.IM had a greater effect on the rheological behavior of the composites than BM,and nano CaCO_(3)treatment most effectively affected the performance of the extrusion molded composites.
基金Supported by Jiangsu University Foundation(Grant No.20JDG37).
文摘Compliant micromechanisms(CMMs)acquire mobility from the deflection of elastic members and have been proven to be robust by millions of silicon MEMS devices.However,the limited deflection of silicon impedes the realization of more sophisticated CMMs,which often require larger deflections.Recently,some novel manufacturing processes have emerged but are not well known by the community.In this paper,the realization of CMMs is reviewed,aiming to provide help to mechanical designers to quickly find the proper realization method for their CMM designs.To this end,the literature surveyed was classified and statistically analyzed,and representative processes were summarized individually to reflect the state of the art of CMM manufacturing.Furthermore,the features of each process were collected into tables to facilitate the reference of readers,and the guidelines for process selection were discussed.The review results indicate that,even though the silicon process remains dominant,great progress has been made in the development of polymer-related and composite-related processes,such as micromolding,SU-8 process,laser ablation,3D printing,and the CNT frameworking.These processes result in constituent materials with a lower Young’s modulus and larger maximum allowable strain than silicon,and therefore allow larger deflection.The geometrical capabilities(e.g.,aspect ratio)of the realization methods should also be considered,because different types of CMMs have different requirements.We conclude that the SU-8 process,3D printing,and carbon nanotube frameworking will play more important roles in the future owing to their excellent comprehensive capabilities.
文摘Simulation technique is an efficient approach to realize the planning and scheduling of manufacturing process of products. An appropriate and efficient manufacturing process model is the basis and key of manufacturing process simulation. By analyzing the features of large-sized and complex products, a method of manufacturing process modeling based on activity network is presented and a mapping algorithm of translating BOM/BOP into the manufacturing process model is designed in detail.
基金supported by the National Natural Science Foundation of China (No.51701061)the Natural Science Foundation of Hebei Province (Nos.E2023202047 and E2021202075)+1 种基金the Key-Area R&D Program of Guangdong Province (No.2020B0101340004)Guangdong Academy of Science (2021GDASYL-20210102002).
文摘Steels are widely used as structural materials,making them essential for supporting our lives and industries.However,further improving the comprehensive properties of steel through traditional trial-and-error methods becomes challenging due to the continuous development and numerous processing parameters involved in steel production.To address this challenge,the application of machine learning methods becomes crucial in establishing complex relationships between manufacturing processes and steel performance.This review begins with a general overview of machine learning methods and subsequently introduces various performance predictions in steel materials.The classification of performance pre-diction was used to assess the current application of machine learning model-assisted design.Several important issues,such as data source and characteristics,intermediate features,algorithm optimization,key feature analysis,and the role of environmental factors,were summarized and analyzed.These insights will be beneficial and enlightening to future research endeavors in this field.
基金The research work presented in this paper is supported by the National Natural Science Foundation of China(Grant No.51675418).
文摘Zero defection manufacturing (ZDM) is the pursuit of the manufacturing industry. However, there is a lack of the implementation method of ZDM in the multi-stage manufacturing process (MMP). Implementing ZDM and controlling product quality in MMP remains an urgent problem in intelligent manufacturing. A novel predict-prevention quality control method in MMP towards ZDM is proposed, including quality characteristics monitoring, key quality characteristics prediction, and assembly quality optimization. The stability of the quality characteristics is detected by analyzing the distribution of quality characteristics. By considering the correlations between different quality characteristics, a deep supervised long-short term memory (SLSTM) prediction network is built for time series prediction of quality characteristics. A long-short term memory-genetic algorithm (LSTM-GA) network is proposed to optimize the assembly quality. By utilizing the proposed quality control method in MMP, unqualified products can be avoided, and ZDM of MMP is implemented. Extensive empirical evaluations on the MMP of compressors validate the applicability and practicability of the proposed method.
基金supported by the National Natural Science Foundation of China(Grant No.41303080)the Youth Promotion Association of the Chinese Academy of Sciences(Grant No.2018499)the National Key R&D Program of China(Grant No.2022YFF0903700)。
文摘Northern Anhui was an important region for diverse bronze culture convergence and extensive metal resource circulation in the Pre-Qin Period.In this paper,metallographic microstructure analysis,chemical composition analysis,and lead isotope ratio analysis were conducted on 12 samples of 6 Warring States Period(476–221 BCE)bronze vessels excavated from Chutai Cemetery M1,Fuyang,Anhui Province,revealing the integrated application of diversified manufacturing processes,such as casting,forging,cold working,and welding and multiple metal minerals.The analytical results showed that 2 Ding vessels(鼎)were made by casting,and 2 He vessels(盒)and 2 Dui vessels(敦)were made by forging followed by cold working.These two types of bronze vessels made by different manufacturing processes have significantly distinct alloy ratios and mineral sources,among which the Cu and Sn contents of the 2 cast bronze vessels are lower and the Pb content is higher,while the Cu and Sn contents of the 4 forged bronze vessels are higher and the Pb content is lower.The lead minerals of the two types of bronze vessels might come from Western Henan and the middle and lower reaches of the Yangtze River,respectively.In addition,the 3 pieces of solder used to weld bronze vessels were all made of pure Sn,their metal minerals should come from the densely distributed area of tin ore in Southern China,and Sn solders were mainly discovered in the Chu culture area during the Eastern Zhou Period.
基金Open access funding provided by HEAL-Link Greece.
文摘Due to space availability limitations and high land costs,there is an increasing development of multi-floor manufacturing(MFM)systems in urban and industrial areas.The problem of coordination in a multi-floor manufacturing process,in the Ramadge Wonham framework,is introduced.The manufacturing chain of each floor and the elevator system are modeled in the form of finite deterministic automata.The models of the multi-floor manufacturing process are parametric with respect to the number of floors and the number of manufacturing machines on each floor.The coordination desired performance is formulated in the form of desired regular languages in analytic forms.The languages are realized by appropriate supervisors in the form of finite deterministic automata.The models of the supervisors are also parametric with respect to the number of floors and the number of manufacturing machines on each floor.The total control of the coordination of the multi-floor manufacturing process is accomplished via a modular supervisory control architecture.The complexity of the supervisors as well as the complexity of the total modular supervisory architecture are determined in analytic forms with respect to the number of floors and the number of manufacturing machines on each floor.The special case of a two floor manufacturing process is presented as an illustrative example.
基金supported by the Fundamental Research Funds for The Central Universities(Grant No.2232021A-08)National Natural Science Foundation of China(GrantNo.51905091)Shanghai Sailing Program(Grand No.19YF1401500).
文摘The prognostics health management(PHM)fromthe systematic viewis critical to the healthy continuous operation of processmanufacturing systems(PMS),with different kinds of dynamic interference events.This paper proposes a three leveled digital twinmodel for the systematic PHMof PMSs.The unit-leveled digital twinmodel of each basic device unit of PMSs is constructed based on edge computing,which can provide real-time monitoring and analysis of the device status.The station-leveled digital twin models in the PMSs are designed to optimize and control the process parameters,which are deployed for the manufacturing execution on the fog server.The shop-leveled digital twin maintenancemodel is designed for production planning,which gives production instructions fromthe private industrial cloud server.To cope with the dynamic disturbances of a PMS,a big data-driven framework is proposed to control the three-level digital twin models,which contains indicator prediction,influence evaluation,and decisionmaking.Finally,a case study with a real chemical fiber system is introduced to illustrate the effectiveness of the digital twin model with edge-fog-cloud computing for the systematic PHM of PMSs.The result demonstrates that the three-leveled digital twin model for the systematic PHM in PMSs works well in the system’s respects.
基金The work was supported by the National Natural Science Foundation of China (Grant Nos. 59990470, 59985004) the National Distinguished Youth Scientific Fund of China (Grant No. 59725514) .
文摘Accessibility is a kind of important design feature of products,and accessibility analysis has been acknowledged as a powerful tool for solving computational manufacturing problems arising from different manufacturing processes.After exploring the relations among approachability,accessibility and visibility,a general method for accessibility analysis using visibility cones (VC) is proposed.With the definition of VC of a point,three kinds of visibility of a feature,namely complete visibility cone (CVC),partial visibility cone (PVC) and local visibility cone (LVC),are defined.A novel approach to computing VCs is formulated by identifying C-obstacles in the C-space,for which a general and efficient algorithm is proposed and implemented by making use of visibility culling.Lastly,we discuss briefly how to realize accessibility analysis in numerically controlled (NC) machining planning,coordinate measuring machines (CMMs) inspection planning and assembly sequence planning with the proposed methods.
基金Item Sponsored by Fundamental Research Funds for the Central Universities of China(N090602007)National Key Technology Research and Development Program in 11th Five-Year Plan Project of China(2006BAE03A09)
文摘Theoretical minimum and actual specific energy consumptions (SEC) of typical manufacturing process (SMP) were studied. Firstly, a process division of a typical SMP in question was conducted with the theory of SEC analysis. Secondly, an exergy analysis model of a subsystem consisting of several parallel processes and a SEC analysis model of SMP were developed. And finally, based on the analysis models, the SEC of SMP was analyzed by means of the statistical significance. The results show that the SEC of typical SMP comprises the theoretical minimum SEC and the additional SEC derived from the irreversibility~ and the SMP has a theoretical minimum SEC of 6.74 GJ/t and an additional SEC of 19.32 GJ/t, which account for 25.88% and 74.12% of the actual SEC, respectively.