Machine learning(ML)has recently enabled many modeling tasks in design,manufacturing,and condition monitoring due to its unparalleled learning ability using existing data.Data have become the limiting factor when impl...Machine learning(ML)has recently enabled many modeling tasks in design,manufacturing,and condition monitoring due to its unparalleled learning ability using existing data.Data have become the limiting factor when implementing ML in industry.However,there is no systematic investigation on how data quality can be assessed and improved for ML-based design and manufacturing.The aim of this survey is to uncover the data challenges in this domain and review the techniques used to resolve them.To establish the background for the subsequent analysis,crucial data terminologies in ML-based modeling are reviewed and categorized into data acquisition,management,analysis,and utilization.Thereafter,the concepts and frameworks established to evaluate data quality and imbalance,including data quality assessment,data readiness,information quality,data biases,fairness,and diversity,are further investigated.The root causes and types of data challenges,including human factors,complex systems,complicated relationships,lack of data quality,data heterogeneity,data imbalance,and data scarcity,are identified and summarized.Methods to improve data quality and mitigate data imbalance and their applications in this domain are reviewed.This literature review focuses on two promising methods:data augmentation and active learning.The strengths,limitations,and applicability of the surveyed techniques are illustrated.The trends of data augmentation and active learning are discussed with respect to their applications,data types,and approaches.Based on this discussion,future directions for data quality improvement and data imbalance mitigation in this domain are identified.展开更多
As a product of the new century,artificial intelligence has been continuously developed and advanced.It has been applied to many fields,especially in the field of mechanical design and manufacturing.With the support o...As a product of the new century,artificial intelligence has been continuously developed and advanced.It has been applied to many fields,especially in the field of mechanical design and manufacturing.With the support of artificial intelligence,mechanical design and manufacturing can not only reduce input costs but also significantly reduce the demand for labor,playing a positive role in improving the design efficiency and quality of mechanical manufacturing[1].This paper studies how to apply artificial intelligence technology to the mechanical design and production process to achieve greater application and development.展开更多
Industry 4.0 as referred to the fourth industrial revolution has endorsed in several national manufacturing initiatives or development plans such as in Germany, the UK, USA and China. A set of important pervasive and ...Industry 4.0 as referred to the fourth industrial revolution has endorsed in several national manufacturing initiatives or development plans such as in Germany, the UK, USA and China. A set of important pervasive and secondary technologies for future manufacturing activities have been identified such as additive manufacturing, sensor technology,展开更多
Although several research works in the literature have focused on studying the capabilities of additive manufacturing(AM) systems, few works have addressed the development of Design for Additive Manufacturing(DfAM) kn...Although several research works in the literature have focused on studying the capabilities of additive manufacturing(AM) systems, few works have addressed the development of Design for Additive Manufacturing(DfAM) knowledge,tools, rules, and methodologies, which has limited the penetration and impact of AM in industry. In this paper a comprehensive review of design and manufacturing strategies for Fused Deposition Modelling(FDM) is presented.Consequently, several DfAM strategies are proposed and analysed based on existing research works and the operation principles, materials, capabilities and limitations of the FDM process. These strategies have been divided into four main groups: geometry, quality, materials and sustainability. The implementation and practicality of the proposed DfAM is illustrated by three case studies. The new proposed DfAM strategies are intended to assist designers and manufacturers when making decisions to satisfy functional needs, while ensuring manufacturability in FDM systems.Moreover, many of these strategies can be applied or extended to other AM processes besides FDM.展开更多
Industry 4.0 as referred to a fourth industrial revolution has endorsed in several national manufacturing development plans such as in Germany, the UK, and China. A set of important pervasive and secondary technologie...Industry 4.0 as referred to a fourth industrial revolution has endorsed in several national manufacturing development plans such as in Germany, the UK, and China. A set of important pervasive and secondary technologies for future manufacturing activities have been identified such as additive manufacturing, sensor technology, big data analytics, Internet of things, robotics, cloud computing, and nanotechnology.展开更多
Digital design and manufacturing have been under pinned by digital modeling, simulation, and automation controls for decades. Under the new market requirement of mass customized products and services, the advancements...Digital design and manufacturing have been under pinned by digital modeling, simulation, and automation controls for decades. Under the new market requirement of mass customized products and services, the advancements in artificial intelligence （AI）, smart technology, virtual reality （VR）, big data, digital twin, robotics and human-centered design are becoming driving forces for the development of future digital design and manufacturing. This special issue focuses on the future digital design and manufacturing especially under the Industry 4.0 framework and beyond. This editorial introduces the papers in this special issue, which linked to the International Workshop on Digital Design and Manufacturing Technologies - Embracing Industry 4.0 and Beyond at Northumbria University in Newcastle, UK, held on 12-13 April 2016. In the Part I of the issue [1], there are 13 papers published in 2016, Vol- ume 29, No 6 of the Chinese Journal of Mechanical Engineering （this journal）.展开更多
The development of mold industry cannot be separated from intelligent manufacturing, which helps it to optimize its technology and transform and upgrade. The skilled talents of mold specialty will also face the new re...The development of mold industry cannot be separated from intelligent manufacturing, which helps it to optimize its technology and transform and upgrade. The skilled talents of mold specialty will also face the new requirements of the industry. Therefore, this paper will make a certain analysis on the problem that the training of mold design and manufacturing professionals in higher vocational colleges is out of line with intelligent manufacturing, and discuss the talent training plan of mold specialty in higher vocational colleges under this background, for your reference.展开更多
The field of automation plays an important role in the field of mechanical design and manufacturing, which has important practical significance for promoting the development of related fields. Compared with the tradit...The field of automation plays an important role in the field of mechanical design and manufacturing, which has important practical significance for promoting the development of related fields. Compared with the traditional manufacturing industry, the mechanical design and manufacturing automation technology is more in line with the development trend of the times. The mechanical industry should correctly grasp the market trend and direction, and grasp the future development trend of the mechanical industry. Relevant enterprise staff should pay enough attention to this, timely pay attention to the latest frontier trends in the industry, continuously optimize and innovate the existing technology, and realize the better development of their own industry.展开更多
Under the new environment, the development of mechanical design and manufacturing has been a good boost, and its technology integration provides a diversified development model for mechanical design and manufacturing....Under the new environment, the development of mechanical design and manufacturing has been a good boost, and its technology integration provides a diversified development model for mechanical design and manufacturing. Research purpose of this article by defining mechanical design and manufacture of current situation and existing problems, analysis of mechanical design and manufacture of new environment characteristics, to explore the mechanical design and manufacturing of the future development direction and specific path, make the whole process of mechanical manufacturing industry upgrading, constantly to meet the requirements of information age and industrial development.展开更多
With the rapid development of economy and the continuous improvement of scientific and technological level, the engineering industry has also achieved rapid development, and gradually changed to rely on technology for...With the rapid development of economy and the continuous improvement of scientific and technological level, the engineering industry has also achieved rapid development, and gradually changed to rely on technology for product research and development to better meet the needs of society. In the future development process, the requirements for mechanical products will be higher and higher, so the mechanical design and manufacturing industry will need to be further diversified, intelligent and digital for structural transformation. Reduce production costs and labor intensity to the greatest extent, and promote the development of machinery manufacturing enterprises towards a higher direction. This paper also analyzes it from many aspects, hoping to be of some help to manufacturing enterprises. Here is a detailed analysis and research.展开更多
With the rapid development of science and technology, people pay more attention to technological innovation, which will have a direct impact on peoples production and life. From the perspective of mechanical manufactu...With the rapid development of science and technology, people pay more attention to technological innovation, which will have a direct impact on peoples production and life. From the perspective of mechanical manufacturing and automation technology, it is necessary to conduct an in-depth analysis of the core technologies, and on this basis, find feasible application strategies, so as to inject more powerful power into economic construction.展开更多
From the perspective of the development trend of mechanical automation, in the future development of science and technology, the mechanical manufacturing industry and mechanical automation technology are increasingly ...From the perspective of the development trend of mechanical automation, in the future development of science and technology, the mechanical manufacturing industry and mechanical automation technology are increasingly closely linked, and their technological integration will gradually deepen, thus significantly improving social benefits.展开更多
Refractory alloys such as tungsten and molybdenum based alloys with high strength,thermal/electrical conductivity,low coefficient of thermal expansion and excellent creep resistances are highly desirable for applicati...Refractory alloys such as tungsten and molybdenum based alloys with high strength,thermal/electrical conductivity,low coefficient of thermal expansion and excellent creep resistances are highly desirable for applications in nuclear facilities,critical components in aerospace and defense components.However,the serious embrittlement limits the engineering usability of some refractory alloys.A lot of research results indicate that the performances of refractory alloys are closely related to the physical/chemical status,such as the interface dimension,interface type,interface composition of their grain boundaries(GBs),phase boundaries(PBs)and other interface features.This paper reviewed the recent progress of simulations and experiments on interface design strategies that achieve high performance refractory alloys.These strategies include GB interface purifying/strengthening,PB interface strengthening and PB/GB synergistic strengthening.Great details are provided on the design/fabrication strategy such as GB interface controlling,PB interface controlling and synergistic control of multi-scaled interfaces.The corresponding performances such as the mechanical property,thermal conductivity,thermal load resistance,thermal stability,irradiation resistance,and oxidation resistance are reviewed in the aspect to the effect of interfaces.In addition,the relationships between these interfaces and material properties are discussed.Finally,future developments and potential new research directions for refractory alloys are proposed.展开更多
In this paper, design and fabrication of a commemorative plaque are described and presented. The plaque was fabricated to honour the memory of the 14 women massacred at L＇Ecole Polytechnique in Montreal. This plaque ...In this paper, design and fabrication of a commemorative plaque are described and presented. The plaque was fabricated to honour the memory of the 14 women massacred at L＇Ecole Polytechnique in Montreal. This plaque is the result of a project partnership between the Faculties of Engineering and Fine Arts, and was sponsored by the Office of the Vice-President Academic and Provost. An art design was selected through a contest coordinated by the Visual Arts Departmment. The selected art design was then turned over to the Mechanical Engineering Department to be converted to a 3-dimensional （3D） solid model and then eventually fabricated on a computer numerical control （CNC） milling machine. The fabricated plaque was unveiled during the December 2010 Memorial event at UVic.展开更多
Mechanical design and manufacturing technology has been greatly improved. At present;China's machinery design and manufacturing industry is taking certain measures;enabling the entire industry to implement intelli...Mechanical design and manufacturing technology has been greatly improved. At present;China's machinery design and manufacturing industry is taking certain measures;enabling the entire industry to implement intelligent digital-related practices and comprehensive transformation;technicians and employees are constantly working to make the entire industry fully intelligent. This article provides a detailed analysis of the design and manufacture of intelligent machines;the whole phenomenon of current mechanical design and manufacturing industry is analyzed. On this basis;analyze and discuss specific application methods and potential problems that may occur in their use;looking forward to the future development of machinery industry.展开更多
Machinery manufacturing industry is a traditional industry, the application of simulation technology in the industry can improve work efficiency, reduce manufacturing costs and promote the industry information, intell...Machinery manufacturing industry is a traditional industry, the application of simulation technology in the industry can improve work efficiency, reduce manufacturing costs and promote the industry information, intelligent, so that it towards the direction of modernization. Therefore, in the process of the rapid development of Chinese society, the development of the machinery industry is very important, and people's daily production and life have a very close relationship. This paper takes Unity3D, VR and other technologies as examples, so as to study the construction of mechanical design virtual simulation system.展开更多
Reconfigurable products and manufacturing systems have enabled manufacturers to provide ＂cost effective＂ variety to the market. In spite of these new technologies, the expense of manufacturing makes it infeasible to...Reconfigurable products and manufacturing systems have enabled manufacturers to provide ＂cost effective＂ variety to the market. In spite of these new technologies, the expense of manufacturing makes it infeasible to supply all the possible variants to the market for some industries. Therefore, the determination of the right number of product variantsto offer in the product portfolios becomes an important consideration. The product portfolio planning problem had been independently well studied from marketing and engineering perspectives. However, advantages can be gained from using a concurrent marketing and engineering approach. Concurrent product development strategies specifically for reconfigurable products and manufacturing systems can allow manufacturers to select best product portfolios from marketing, product design and manufacturing perspectives. A methodology for the concurrent design of a product portfolio and assembly system is presented. The objective of the concurrent product portfolio planning and assembly system design problem is to obtain the product variants that will make up the product portfolio such that oversupply of optional modules is minimized and the assembly line efficiency is maximized. Explicit design of the assembly system is obtained during the solution of the problem. It is assumed that the demand for optional modules and the assembly times for these modules are known a priori. A genetic algorithm is used in the solution of the problem. The basic premise of this methodology is that the selected product portfolio has a significant impact on the solution of the assembly line balancing problem. An example is used to validate this hypothesis. The example is then further developed to demonstrate how the methodology can be used to obtain the optimal product portfolio. This approach is intended for use by manufacturers during the early design stages of product family design.展开更多
Researched on the design and manufacturing of machine tool bed made by Steel-fibber Polymer Concrete(SFPC),which analyzed the static,dynamic and thermal performances of the bed.The results of study prove that machine ...Researched on the design and manufacturing of machine tool bed made by Steel-fibber Polymer Concrete(SFPC),which analyzed the static,dynamic and thermal performances of the bed.The results of study prove that machine tool bed made with SFPC is much more superiority than made in cast iron in dynamic and thermal perform- ances,and is more superiority then made in Polymer Concrete (PC) in static perform- ances.It can be concluded that the static,dynamic and thermal properties of machine tool can be improved by manufacturing machine tool bed with SFPC.Also SFPC machine tool bed posses some other advantages in the following: short development time,simple pro- duction process,reducing cost cost,saving energy,iron and steel.展开更多
In musical instruments, the geometric design and material features of the instrument are the most important factors that determine the sound characteristics of the instrument. Traditional replication and experiment-ba...In musical instruments, the geometric design and material features of the instrument are the most important factors that determine the sound characteristics of the instrument. Traditional replication and experiment-based handcrafting methods are predominant in the production of Turkish Folk Music wind instruments. The instrument manufacturing and standardization approaches, which include the relevant rules of physics and engineering practices, are limited purely to prototype studies for scientific research purposes. It is almost impossible to find studies on Turkish Folk Music wind instrument design and production involving computer aided design and engineering applications. In this study, an example Turkish woodwind instrument, the Turkish Treble Recorder (dilli kaval) is considered, and the air flow behaviour and acoustic (sound) power magnitudes that occur at different air flow rates are simulated in a computer environment using a Computational Fluid Dynamics (CFD) simulation technique. In the study, numerical and visual outputs related to air behaviour at different air flow rates that may be used in the instrument manufacturing phases were obtained. Acoustic power level was also measured experimentally. Simulation outputs (the acoustic power level) were compared to experimental results in order to validate the simulation results. The comparison revealed that the highest relative difference was calculated as 13.32(%). This value indicated that the simulation results were reasonably consistent with the results of the experimental measurement. Additionally, this study was constructed as a case study that may provide reference for future research studies in this field.展开更多
基金funded by the McGill University Graduate Excellence Fellowship Award(00157)the Mitacs Accelerate Program(IT13369)the McGill Engineering Doctoral Award(MEDA).
文摘Machine learning(ML)has recently enabled many modeling tasks in design,manufacturing,and condition monitoring due to its unparalleled learning ability using existing data.Data have become the limiting factor when implementing ML in industry.However,there is no systematic investigation on how data quality can be assessed and improved for ML-based design and manufacturing.The aim of this survey is to uncover the data challenges in this domain and review the techniques used to resolve them.To establish the background for the subsequent analysis,crucial data terminologies in ML-based modeling are reviewed and categorized into data acquisition,management,analysis,and utilization.Thereafter,the concepts and frameworks established to evaluate data quality and imbalance,including data quality assessment,data readiness,information quality,data biases,fairness,and diversity,are further investigated.The root causes and types of data challenges,including human factors,complex systems,complicated relationships,lack of data quality,data heterogeneity,data imbalance,and data scarcity,are identified and summarized.Methods to improve data quality and mitigate data imbalance and their applications in this domain are reviewed.This literature review focuses on two promising methods:data augmentation and active learning.The strengths,limitations,and applicability of the surveyed techniques are illustrated.The trends of data augmentation and active learning are discussed with respect to their applications,data types,and approaches.Based on this discussion,future directions for data quality improvement and data imbalance mitigation in this domain are identified.
文摘As a product of the new century,artificial intelligence has been continuously developed and advanced.It has been applied to many fields,especially in the field of mechanical design and manufacturing.With the support of artificial intelligence,mechanical design and manufacturing can not only reduce input costs but also significantly reduce the demand for labor,playing a positive role in improving the design efficiency and quality of mechanical manufacturing[1].This paper studies how to apply artificial intelligence technology to the mechanical design and production process to achieve greater application and development.
文摘Industry 4.0 as referred to the fourth industrial revolution has endorsed in several national manufacturing initiatives or development plans such as in Germany, the UK, USA and China. A set of important pervasive and secondary technologies for future manufacturing activities have been identified such as additive manufacturing, sensor technology,
基金Supported by National Science and Technology Council(CONACYT)of Mexico(Grant No.CB-2010-01-154430)PROMEP Program of the Public Education Secretariat(SEP)of MexicoFund for Research Support(FAI)of UASLP
文摘Although several research works in the literature have focused on studying the capabilities of additive manufacturing(AM) systems, few works have addressed the development of Design for Additive Manufacturing(DfAM) knowledge,tools, rules, and methodologies, which has limited the penetration and impact of AM in industry. In this paper a comprehensive review of design and manufacturing strategies for Fused Deposition Modelling(FDM) is presented.Consequently, several DfAM strategies are proposed and analysed based on existing research works and the operation principles, materials, capabilities and limitations of the FDM process. These strategies have been divided into four main groups: geometry, quality, materials and sustainability. The implementation and practicality of the proposed DfAM is illustrated by three case studies. The new proposed DfAM strategies are intended to assist designers and manufacturers when making decisions to satisfy functional needs, while ensuring manufacturability in FDM systems.Moreover, many of these strategies can be applied or extended to other AM processes besides FDM.
文摘Industry 4.0 as referred to a fourth industrial revolution has endorsed in several national manufacturing development plans such as in Germany, the UK, and China. A set of important pervasive and secondary technologies for future manufacturing activities have been identified such as additive manufacturing, sensor technology, big data analytics, Internet of things, robotics, cloud computing, and nanotechnology.
文摘Digital design and manufacturing have been under pinned by digital modeling, simulation, and automation controls for decades. Under the new market requirement of mass customized products and services, the advancements in artificial intelligence （AI）, smart technology, virtual reality （VR）, big data, digital twin, robotics and human-centered design are becoming driving forces for the development of future digital design and manufacturing. This special issue focuses on the future digital design and manufacturing especially under the Industry 4.0 framework and beyond. This editorial introduces the papers in this special issue, which linked to the International Workshop on Digital Design and Manufacturing Technologies - Embracing Industry 4.0 and Beyond at Northumbria University in Newcastle, UK, held on 12-13 April 2016. In the Part I of the issue [1], there are 13 papers published in 2016, Vol- ume 29, No 6 of the Chinese Journal of Mechanical Engineering （this journal）.
文摘The development of mold industry cannot be separated from intelligent manufacturing, which helps it to optimize its technology and transform and upgrade. The skilled talents of mold specialty will also face the new requirements of the industry. Therefore, this paper will make a certain analysis on the problem that the training of mold design and manufacturing professionals in higher vocational colleges is out of line with intelligent manufacturing, and discuss the talent training plan of mold specialty in higher vocational colleges under this background, for your reference.
文摘The field of automation plays an important role in the field of mechanical design and manufacturing, which has important practical significance for promoting the development of related fields. Compared with the traditional manufacturing industry, the mechanical design and manufacturing automation technology is more in line with the development trend of the times. The mechanical industry should correctly grasp the market trend and direction, and grasp the future development trend of the mechanical industry. Relevant enterprise staff should pay enough attention to this, timely pay attention to the latest frontier trends in the industry, continuously optimize and innovate the existing technology, and realize the better development of their own industry.
文摘Under the new environment, the development of mechanical design and manufacturing has been a good boost, and its technology integration provides a diversified development model for mechanical design and manufacturing. Research purpose of this article by defining mechanical design and manufacture of current situation and existing problems, analysis of mechanical design and manufacture of new environment characteristics, to explore the mechanical design and manufacturing of the future development direction and specific path, make the whole process of mechanical manufacturing industry upgrading, constantly to meet the requirements of information age and industrial development.
文摘With the rapid development of economy and the continuous improvement of scientific and technological level, the engineering industry has also achieved rapid development, and gradually changed to rely on technology for product research and development to better meet the needs of society. In the future development process, the requirements for mechanical products will be higher and higher, so the mechanical design and manufacturing industry will need to be further diversified, intelligent and digital for structural transformation. Reduce production costs and labor intensity to the greatest extent, and promote the development of machinery manufacturing enterprises towards a higher direction. This paper also analyzes it from many aspects, hoping to be of some help to manufacturing enterprises. Here is a detailed analysis and research.
文摘With the rapid development of science and technology, people pay more attention to technological innovation, which will have a direct impact on peoples production and life. From the perspective of mechanical manufacturing and automation technology, it is necessary to conduct an in-depth analysis of the core technologies, and on this basis, find feasible application strategies, so as to inject more powerful power into economic construction.
文摘From the perspective of the development trend of mechanical automation, in the future development of science and technology, the mechanical manufacturing industry and mechanical automation technology are increasingly closely linked, and their technological integration will gradually deepen, thus significantly improving social benefits.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.:51771184,11735015,51801203,51771181)the Natural Science Foundation of Anhui Province(Grant No.1808085QE132)+2 种基金the Open Project of State Key Laboratory of Environment friendly Energy Materials(18kfhg02)a fund from the Science and Technology on Surface Physics and Chemistry Laboratory(Grant No.JZX7Y201901SY00900103)the Innovation Center of Nuclear Materials for National Defense Industry。
文摘Refractory alloys such as tungsten and molybdenum based alloys with high strength,thermal/electrical conductivity,low coefficient of thermal expansion and excellent creep resistances are highly desirable for applications in nuclear facilities,critical components in aerospace and defense components.However,the serious embrittlement limits the engineering usability of some refractory alloys.A lot of research results indicate that the performances of refractory alloys are closely related to the physical/chemical status,such as the interface dimension,interface type,interface composition of their grain boundaries(GBs),phase boundaries(PBs)and other interface features.This paper reviewed the recent progress of simulations and experiments on interface design strategies that achieve high performance refractory alloys.These strategies include GB interface purifying/strengthening,PB interface strengthening and PB/GB synergistic strengthening.Great details are provided on the design/fabrication strategy such as GB interface controlling,PB interface controlling and synergistic control of multi-scaled interfaces.The corresponding performances such as the mechanical property,thermal conductivity,thermal load resistance,thermal stability,irradiation resistance,and oxidation resistance are reviewed in the aspect to the effect of interfaces.In addition,the relationships between these interfaces and material properties are discussed.Finally,future developments and potential new research directions for refractory alloys are proposed.
文摘In this paper, design and fabrication of a commemorative plaque are described and presented. The plaque was fabricated to honour the memory of the 14 women massacred at L＇Ecole Polytechnique in Montreal. This plaque is the result of a project partnership between the Faculties of Engineering and Fine Arts, and was sponsored by the Office of the Vice-President Academic and Provost. An art design was selected through a contest coordinated by the Visual Arts Departmment. The selected art design was then turned over to the Mechanical Engineering Department to be converted to a 3-dimensional （3D） solid model and then eventually fabricated on a computer numerical control （CNC） milling machine. The fabricated plaque was unveiled during the December 2010 Memorial event at UVic.
文摘Mechanical design and manufacturing technology has been greatly improved. At present;China's machinery design and manufacturing industry is taking certain measures;enabling the entire industry to implement intelligent digital-related practices and comprehensive transformation;technicians and employees are constantly working to make the entire industry fully intelligent. This article provides a detailed analysis of the design and manufacture of intelligent machines;the whole phenomenon of current mechanical design and manufacturing industry is analyzed. On this basis;analyze and discuss specific application methods and potential problems that may occur in their use;looking forward to the future development of machinery industry.
文摘Machinery manufacturing industry is a traditional industry, the application of simulation technology in the industry can improve work efficiency, reduce manufacturing costs and promote the industry information, intelligent, so that it towards the direction of modernization. Therefore, in the process of the rapid development of Chinese society, the development of the machinery industry is very important, and people's daily production and life have a very close relationship. This paper takes Unity3D, VR and other technologies as examples, so as to study the construction of mechanical design virtual simulation system.
文摘Reconfigurable products and manufacturing systems have enabled manufacturers to provide ＂cost effective＂ variety to the market. In spite of these new technologies, the expense of manufacturing makes it infeasible to supply all the possible variants to the market for some industries. Therefore, the determination of the right number of product variantsto offer in the product portfolios becomes an important consideration. The product portfolio planning problem had been independently well studied from marketing and engineering perspectives. However, advantages can be gained from using a concurrent marketing and engineering approach. Concurrent product development strategies specifically for reconfigurable products and manufacturing systems can allow manufacturers to select best product portfolios from marketing, product design and manufacturing perspectives. A methodology for the concurrent design of a product portfolio and assembly system is presented. The objective of the concurrent product portfolio planning and assembly system design problem is to obtain the product variants that will make up the product portfolio such that oversupply of optional modules is minimized and the assembly line efficiency is maximized. Explicit design of the assembly system is obtained during the solution of the problem. It is assumed that the demand for optional modules and the assembly times for these modules are known a priori. A genetic algorithm is used in the solution of the problem. The basic premise of this methodology is that the selected product portfolio has a significant impact on the solution of the assembly line balancing problem. An example is used to validate this hypothesis. The example is then further developed to demonstrate how the methodology can be used to obtain the optimal product portfolio. This approach is intended for use by manufacturers during the early design stages of product family design.
基金the Education Department of Liaoning Prorince(2004F030)
文摘Researched on the design and manufacturing of machine tool bed made by Steel-fibber Polymer Concrete(SFPC),which analyzed the static,dynamic and thermal performances of the bed.The results of study prove that machine tool bed made with SFPC is much more superiority than made in cast iron in dynamic and thermal perform- ances,and is more superiority then made in Polymer Concrete (PC) in static perform- ances.It can be concluded that the static,dynamic and thermal properties of machine tool can be improved by manufacturing machine tool bed with SFPC.Also SFPC machine tool bed posses some other advantages in the following: short development time,simple pro- duction process,reducing cost cost,saving energy,iron and steel.
文摘In musical instruments, the geometric design and material features of the instrument are the most important factors that determine the sound characteristics of the instrument. Traditional replication and experiment-based handcrafting methods are predominant in the production of Turkish Folk Music wind instruments. The instrument manufacturing and standardization approaches, which include the relevant rules of physics and engineering practices, are limited purely to prototype studies for scientific research purposes. It is almost impossible to find studies on Turkish Folk Music wind instrument design and production involving computer aided design and engineering applications. In this study, an example Turkish woodwind instrument, the Turkish Treble Recorder (dilli kaval) is considered, and the air flow behaviour and acoustic (sound) power magnitudes that occur at different air flow rates are simulated in a computer environment using a Computational Fluid Dynamics (CFD) simulation technique. In the study, numerical and visual outputs related to air behaviour at different air flow rates that may be used in the instrument manufacturing phases were obtained. Acoustic power level was also measured experimentally. Simulation outputs (the acoustic power level) were compared to experimental results in order to validate the simulation results. The comparison revealed that the highest relative difference was calculated as 13.32(%). This value indicated that the simulation results were reasonably consistent with the results of the experimental measurement. Additionally, this study was constructed as a case study that may provide reference for future research studies in this field.
