A new method that designs and implements the component-based distributed & hierarchical flexible manufacturing control software is described with a component concept in this paper. The proposed method takes aim at...A new method that designs and implements the component-based distributed & hierarchical flexible manufacturing control software is described with a component concept in this paper. The proposed method takes aim at improving the flexibility and reliability of the control system. On the basis of describing the concepts of component-based software and the distributed object technology, the architecture of the component-based software of the control system is suggested with the Common Object Request Broker Architecture (CORBA). And then, we propose a design method for component-based distributed & hierarchical flexible manufacturing control system. Finally, to verify the software design method, a prototype flexible manufacturing control system software has been implemented in Orbix 2.3c, VC + + 6. 0 and has been tested in connection with the physical flexible manufacturing shop at the WuXi Professional Institute.展开更多
Many industrial companies and researchers are looking for more efficient model driven engineering approaches (MDE) in software engineering of manufacturing automation systems (MS) especially for logic control programm...Many industrial companies and researchers are looking for more efficient model driven engineering approaches (MDE) in software engineering of manufacturing automation systems (MS) especially for logic control programming, but are uncertain about the applicability and effort needed to implement those approaches in comparison to classical Programmable Logic Controller?(PLC) programming with IEC 61131-3. The paper summarizes results of usability experiments evaluating UML and SysML as software engineering notations for a MDE applied in the domain of manufacturing systems. Modeling MS needs to cover the domain specific characteristics,?i.e.?hybrid process, real time requirements and communication requirements. In addition the paper presents factors, constraint and practical experience for the development of further usability experiments. The paper gives examples of notational expressiveness and weaknesses of UML and SysML. The appendix delivers detailed master models, representing the correct best suited model, and evaluation schemes of the experiment, which is helpful if setting up own empirical experiments.展开更多
The purpose of this paper is to provide the software engineer with tools from the field of manufacturing as an aid to improving software process and product quality. Process involves classical manufacturing methods, s...The purpose of this paper is to provide the software engineer with tools from the field of manufacturing as an aid to improving software process and product quality. Process involves classical manufacturing methods, such as statistical quality control applied to product testing, which is designed to monitor and correct the process when the process yields product quality that fails to meet specifications. Product quality is measured by metrics, such as failure count occurring on software during testing. When the process and product quality are out of control, we show what remedial action to take to bring both the process and product under control. NASA Space Shuttle failure data are used to illustrate the process methods.展开更多
This paper presents an effective decision making framework for software selection in manufacturing industries using a multiple criteria decision making method, Preference Ranking Organization Method for Enrichment Eva...This paper presents an effective decision making framework for software selection in manufacturing industries using a multiple criteria decision making method, Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE). The method is improved in the present work by integrating with analytic hierarchy process (AHP) and the fuzzy logic. Fuzzy logic is introduced to handle the imprecision of the human decision making process. The proposed decision making framework is practical for ranking competing software products in terms of their overall performance with respect to multiple criteria. An example is included to illustrate the approach.展开更多
IoT technologies are being rapidly adopted for manufacturing automation, remote machine diagnostics, prognostic health management of industrial machines and supply chain management. A recent on-demand model of manufac...IoT technologies are being rapidly adopted for manufacturing automation, remote machine diagnostics, prognostic health management of industrial machines and supply chain management. A recent on-demand model of manufacturing that is leveraging IoT technologies is called Cloud-Based Manufacturing. We propose a Software-Defined Industrial Internet of Things (SD-IIoT) platform for as a key enabler for cloud-manufacturing, allowing flexible integration of legacy shop floor equipment into the platform. SD-IIoT enables access to manufacturing resources and allows exchange of data between industrial machines and cloud-based manufacturing applications.展开更多
This study evaluates the Fuzzy Analytical Hierarchy Process(FAHP)as a multi-criteria decision(MCD)support tool for selecting appropriate additive manufacturing(AM)techniques that align with cleaner production and envi...This study evaluates the Fuzzy Analytical Hierarchy Process(FAHP)as a multi-criteria decision(MCD)support tool for selecting appropriate additive manufacturing(AM)techniques that align with cleaner production and environmental sustainability.The FAHP model was validated using an example of the production of aircraft components(specifically fuselage)employing AM technologies such as Wire Arc Additive Manufacturing(WAAM),laser powder bed fusion(L-PBF),Binder Jetting(BJ),Selective Laser Sintering(SLS),and Laser Metal Deposition(LMD).The selection criteria prioritized eco-friendly manufacturing considerations,including the quality and properties of the final product(e.g.,surface finish,high strength,and corrosion resistance),service and functional requirements,weight reduction for improved energy efficiency(lightweight structures),and environmental responsibility.Sustainability metrics,such as cost-effectiveness,material efficiency,waste minimization,and environmental impact,are central to the evaluation process.A computer-aided modeling approach was also used to simulate the performance of aluminum(AA7075 T6),steel(304),and titanium alloy(Ti6Al4V)for fuselage development.The results demonstrate that MCD approaches such as FAHP can effectively guide the selection of AM technologies that meet functional and technical requirements while minimizing environmental degradation footprints.Furthermore,the aluminumalloy outperformed the other materials investigated in the simulation with the lowest stress concentration and least deformation.This study contributes to advancing cleaner production practices by providing a decision-making framework for sustainable and eco-friendly manufacturing,enabling manufacturers to adopt AM technologies that promote environmental responsibility and sustainable development,while maintaining product quality and performance.展开更多
AIM:To support probe-based confocal laser endomi-croscopy (pCLE) diagnosis by designing software for the automated classification of colonic polyps. METHODS:Intravenous fluorescein pCLE imaging of colorectal lesions w...AIM:To support probe-based confocal laser endomi-croscopy (pCLE) diagnosis by designing software for the automated classification of colonic polyps. METHODS:Intravenous fluorescein pCLE imaging of colorectal lesions was performed on patients under-going screening and surveillance colonoscopies, followed by polypectomies. All resected specimens were reviewed by a reference gastrointestinal pathologist blinded to pCLE information. Histopathology was used as the criterion standard for the differentiation between neoplastic and non-neoplastic lesions. The pCLE video sequences, recorded for each polyp, were analyzed off-line by 2 expert endoscopists who were blinded to the endoscopic characteristics and histopathology. These pCLE videos, along with their histopathology diagnosis, were used to train the automated classification software which is a content-based image retrieval technique followed by k-nearest neighbor classification. The performance of the off-line diagnosis of pCLE videos established by the 2 expert endoscopists was compared with that of automated pCLE software classification. All evaluations were performed using leave-one-patient- out cross-validation to avoid bias. RESULTS:Colorectal lesions (135) were imaged in 71 patients. Based on histopathology, 93 of these 135 lesions were neoplastic and 42 were non-neoplastic. The study found no statistical significance for the difference between the performance of automated pCLE software classification (accuracy 89.6%, sensitivity 92.5%, specificity 83.3%, using leave-one-patient-out cross-validation) and the performance of the off-line diagnosis of pCLE videos established by the 2 expert endoscopists (accuracy 89.6%, sensitivity 91.4%, specificity 85.7%). There was very low power (< 6%) to detect the observed differences. The 95% confidence intervals for equivalence testing were:-0.073 to 0.073 for accuracy, -0.068 to 0.089 for sensitivity and -0.18 to 0.13 for specificity. The classification software proposed in this study is not a "black box" but an informative tool based on the query by example model that produces, as intermediate results, visually similar annotated videos that are directly interpretable by the endoscopist. CONCLUSION:The proposed software for automated classification of pCLE videos of colonic polyps achieves high performance, comparable to that of off-line diagnosis of pCLE videos established by expert endoscopists.展开更多
China-made 5-axis simultaneous contouring CNC machine tool and domestically developed industrial computer-aided manufacture (CAM) technology were used for full crown fabrication and measurement of crown accuracy, wi...China-made 5-axis simultaneous contouring CNC machine tool and domestically developed industrial computer-aided manufacture (CAM) technology were used for full crown fabrication and measurement of crown accuracy, with an attempt to establish an open CAM system for dental processing and to promote the introduction of domestic dental computer-aided design (CAD)/CAM system. Commercially available scanning equipment was used to make a basic digital tooth model after preparation of crown, and CAD software that comes with the scanning device was employed to design the crown by using domestic industrial CAM software to process the crown data in order to generate a solid model for machining purpose, and then China-made 5-axis simultaneous contouring CNC machine tool was used to complete machining of the whole crown and the internal accuracy of the crown internal was measured by using 3D-MicroCT. The results showed that China-made 5-axis simultaneous contouring CNC machine tool in combination with domestic industrial CAM technology can be used for crown making and the crown was well positioned in die. The internal accuracy was successfully measured by using 3D-MicroCT. It is concluded that an open CAM system for den-tistry on the basis of China-made 5-axis simultaneous contouring CNC machine tool and domestic industrial CAM software has been established, and development of the system will promote the introduction of domestically-produced dental CAD/CAM system.展开更多
Additive manufacturing(AM)technology enables the creation of a wide variety of assemblies and complex shapes from three-dimensional model data in a bottom-up,layer-by-layer manner.Therefore,AM has revolutionized the m...Additive manufacturing(AM)technology enables the creation of a wide variety of assemblies and complex shapes from three-dimensional model data in a bottom-up,layer-by-layer manner.Therefore,AM has revolutionized the modern manufacturing industry,attracting increasing interest from both academic and industrial fields.The Rapid Manufacturing Center(RMC)of the School of Materials Science and Engineering at the Huazhong Univer-sity of Science and Technology(HUST),one of the earliest and most powerful AM research teams in China,has been engaged in AM research since 1991.Aiming to address the“stuck neck”problems of specific high-strength products for AM,the RMC has conducted full-chain research in the aspects of special materials,processes,equip-ment,and applications for AM.Moreover,it has formed a multi-disciplinary research team over the past three decades.Relevant research achievements in the AM field include winning five national awards,more than ten first prizes,and more than ten second prizes at the provincial and ministerial levels.The RMC was complimented as“the world’s most influential organization in the laser AM field in 2018”by Virtual and Physical Prototyping(an international authoritative magazine of AM).Moreover,their industrialization achievements were evaluated as“having affected countries such as Singapore,South Korea,and the United States”by an international author-itative Wohlers Report on AM.In this study,we first summarize the representative research achievements of the RMC in the AM field.These include the preparation and processing technology of high-performance polymeric,metallic,and ceramic materials for AM;advanced processing technology and software/equipment for AM;and typical AM-fabricated products and their applications.Further,we discuss the latest research achievements in cutting-edge 4D printing in terms of feedstock selection,printing processes,induction strategies,and potential ap-plications.Finally,we provide insights into the future directions of AM technology development:(ⅰ)Evolving from three-dimensional printing to multi-dimensional printing,(ⅱ)transitioning from plane slicing to curved surface slicing to woven slicing,(ⅲ)enhancing efficient formation from dot-line-sheet-volume printing,(ⅳ)shifting from single material to multi-materials AM,(ⅴ)advancing from the multiscale direction of macroscopic-mesoscopic-microscopic structures,(ⅵ)integrating material preparation with forming integration,(ⅶ)expanding from small batch to large batch.展开更多
The software-based computer numerical control(CNC) system includes three types of tasks: periodic real-time tasks, aperiodic real-time tasks, and non-real-time tasks. The tasks are characterized by concurrency, hyb...The software-based computer numerical control(CNC) system includes three types of tasks: periodic real-time tasks, aperiodic real-time tasks, and non-real-time tasks. The tasks are characterized by concurrency, hybridization, and correlation, which make system implementation difficult. The conventional scheduling algorithm can not meet the demands of system implementation in the software-based CNC system completely. The uncertainty factors when running real-time tasks affect control performance by degrading manufacturing accuracy as a result of system resource and processor use restrictions. To address the technical difficulty of embedded system implementation, a novel fuzzy feedback scheduling algorithm based on output jitter of key real-time tasks for a software-based CNC system is proposed. Time characteristics, such as sampling jitter, input-output jitter, and non-schedulability are discussed, followed by quantification through simulations of the impact of time characteristics on manufacturing accuracy. On the basis of this research, the scheduler architecture is designed, and then the algorithm table is calculated. When the system resource changes, the key periodic real-time tasks meet their deadlines by means of dynamically adjusting the task period. The simulated results show that the machining precision rises by an order of magnitude for the proposed scheduler in resource-constrained software-based CNC systems. Moreover, unlike conventional feedback scheduling methods, the algorithm in this paper does not rely on the availability of task execution times and is easy to implement while incurring only a small overhead.展开更多
Aim: To establish a rat and mouse epididymal map based on the use of the Epiquatre automatic software for histologic image analysis. Methods: Epididymides from five adult rats and five adult mice were fixed in alcoh...Aim: To establish a rat and mouse epididymal map based on the use of the Epiquatre automatic software for histologic image analysis. Methods: Epididymides from five adult rats and five adult mice were fixed in alcoholic Bouin's fixative and embedded in paraffin. Serial longitudinal sections through the medial aspect of the organ were cut at 10 jam and stained with hematoxylin and eosin. As determined from major connective tissue septa, nine subdivisions of the rat epididymis and seven for the mouse were determined, consisting of five sub-regions in the caput (rat and mouse), one (mouse) or three (rat) in the corpus and one in the cauda (rat and mouse). Using the Epiquatre software, several tubular, luminal and epithelial morphometric parameters were evaluated. Results: Statistical comparison of the quantitative parameters revealed regional differences (2-5 in the rat, 3-6 in the mouse, dependent on parameters) with caput regions 1 and 2 being largely distinguishable from the similar remaining caput and corpus, which were in turn recognizable from the cauda regions in both species. Conclusion: The use of the Epiquatre software allowed us to establish regression curves for different morphometric parameters that can permit the detection of changes in their values under different pathological or experimental conditions. (Asian J Androl 2005 Sep; 7: 267-275)展开更多
Custom-made esthetic finger prostheses, which are used for rehabilitation of patients with missing or impaired fingers, have been fabricated manually. However, such fabrication is time-consuming and requires manual sk...Custom-made esthetic finger prostheses, which are used for rehabilitation of patients with missing or impaired fingers, have been fabricated manually. However, such fabrication is time-consuming and requires manual skill. Here we propose a computer-aided method for fabricating finger pros-theses to save time and allow fabrications that do not require considerable manual skill. In this method, the dimensions of a patient’s healthy finger on the contralateral hand are first measured using a caliper. Using these dimensions, a three-dimensional model is constructed for fabricating a prosthesis for the patient’s impaired finger. Using the 3D model, a mold is designed using 3D modeling tools and a computer-aided design system. The resulting mold is then fabricated using a 3D printer. A finger prosthesis is fabricated by pouring silicone resin into the mold. A finger prosthesis for a volunteer was experimentally fabricated according to the proposed method. To evaluate the size and shape of the finger prosthesis, the difference between the finger prosthesis and the original finger of the volunteer was analyzed. Because the average difference between them was 0.25 mm, it was concluded that the proposed method could be used to fabricate a finger prosthesis of adequate size and shape.展开更多
A method for designing real-time distributed controllers of discrete manufacturing systems is presented. The approach held is agent based;the controller strategy is distributed into several interacting agents that ope...A method for designing real-time distributed controllers of discrete manufacturing systems is presented. The approach held is agent based;the controller strategy is distributed into several interacting agents that operate each one on a part of the manufacturing process;these agents may be distributed into several interconnected processors. The proposed method consists of a modelling methodology and software development framework that provides a generic agent architecture and communication facilities supporting the interaction among agents.展开更多
At this stage, with the improvement of social living standards, as well as the rapid development of new science and technology, computer has become an indispensable new technology in the market economy environment and...At this stage, with the improvement of social living standards, as well as the rapid development of new science and technology, computer has become an indispensable new technology in the market economy environment and people's work and life, and the National Research on the computer industry is gradually strengthened. Driven by the computer industry, the economic benefits of various industries have been greatly improved. At present, computer-aided technology is mainly used in mechanical design and manufacturing. The application of this technology can greatly improve the work efficiency of mechanical design and manufacturing, ensure the design and manufacturing quality of various parts, meet people's demand standards, and create better development space for enterprises.The combination of computer-aided technology and mechanical design and manufacturing is an inevitable trend of the times, and also an important choice to create social and economic benefits.展开更多
基金Supported by National High Technology Development plan(Item No.:2001AA412250)and Shanghai Science & Technology Development Project(Item No.:02FK04)
文摘A new method that designs and implements the component-based distributed & hierarchical flexible manufacturing control software is described with a component concept in this paper. The proposed method takes aim at improving the flexibility and reliability of the control system. On the basis of describing the concepts of component-based software and the distributed object technology, the architecture of the component-based software of the control system is suggested with the Common Object Request Broker Architecture (CORBA). And then, we propose a design method for component-based distributed & hierarchical flexible manufacturing control system. Finally, to verify the software design method, a prototype flexible manufacturing control system software has been implemented in Orbix 2.3c, VC + + 6. 0 and has been tested in connection with the physical flexible manufacturing shop at the WuXi Professional Institute.
文摘Many industrial companies and researchers are looking for more efficient model driven engineering approaches (MDE) in software engineering of manufacturing automation systems (MS) especially for logic control programming, but are uncertain about the applicability and effort needed to implement those approaches in comparison to classical Programmable Logic Controller?(PLC) programming with IEC 61131-3. The paper summarizes results of usability experiments evaluating UML and SysML as software engineering notations for a MDE applied in the domain of manufacturing systems. Modeling MS needs to cover the domain specific characteristics,?i.e.?hybrid process, real time requirements and communication requirements. In addition the paper presents factors, constraint and practical experience for the development of further usability experiments. The paper gives examples of notational expressiveness and weaknesses of UML and SysML. The appendix delivers detailed master models, representing the correct best suited model, and evaluation schemes of the experiment, which is helpful if setting up own empirical experiments.
文摘The purpose of this paper is to provide the software engineer with tools from the field of manufacturing as an aid to improving software process and product quality. Process involves classical manufacturing methods, such as statistical quality control applied to product testing, which is designed to monitor and correct the process when the process yields product quality that fails to meet specifications. Product quality is measured by metrics, such as failure count occurring on software during testing. When the process and product quality are out of control, we show what remedial action to take to bring both the process and product under control. NASA Space Shuttle failure data are used to illustrate the process methods.
文摘This paper presents an effective decision making framework for software selection in manufacturing industries using a multiple criteria decision making method, Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE). The method is improved in the present work by integrating with analytic hierarchy process (AHP) and the fuzzy logic. Fuzzy logic is introduced to handle the imprecision of the human decision making process. The proposed decision making framework is practical for ranking competing software products in terms of their overall performance with respect to multiple criteria. An example is included to illustrate the approach.
文摘IoT technologies are being rapidly adopted for manufacturing automation, remote machine diagnostics, prognostic health management of industrial machines and supply chain management. A recent on-demand model of manufacturing that is leveraging IoT technologies is called Cloud-Based Manufacturing. We propose a Software-Defined Industrial Internet of Things (SD-IIoT) platform for as a key enabler for cloud-manufacturing, allowing flexible integration of legacy shop floor equipment into the platform. SD-IIoT enables access to manufacturing resources and allows exchange of data between industrial machines and cloud-based manufacturing applications.
文摘This study evaluates the Fuzzy Analytical Hierarchy Process(FAHP)as a multi-criteria decision(MCD)support tool for selecting appropriate additive manufacturing(AM)techniques that align with cleaner production and environmental sustainability.The FAHP model was validated using an example of the production of aircraft components(specifically fuselage)employing AM technologies such as Wire Arc Additive Manufacturing(WAAM),laser powder bed fusion(L-PBF),Binder Jetting(BJ),Selective Laser Sintering(SLS),and Laser Metal Deposition(LMD).The selection criteria prioritized eco-friendly manufacturing considerations,including the quality and properties of the final product(e.g.,surface finish,high strength,and corrosion resistance),service and functional requirements,weight reduction for improved energy efficiency(lightweight structures),and environmental responsibility.Sustainability metrics,such as cost-effectiveness,material efficiency,waste minimization,and environmental impact,are central to the evaluation process.A computer-aided modeling approach was also used to simulate the performance of aluminum(AA7075 T6),steel(304),and titanium alloy(Ti6Al4V)for fuselage development.The results demonstrate that MCD approaches such as FAHP can effectively guide the selection of AM technologies that meet functional and technical requirements while minimizing environmental degradation footprints.Furthermore,the aluminumalloy outperformed the other materials investigated in the simulation with the lowest stress concentration and least deformation.This study contributes to advancing cleaner production practices by providing a decision-making framework for sustainable and eco-friendly manufacturing,enabling manufacturers to adopt AM technologies that promote environmental responsibility and sustainable development,while maintaining product quality and performance.
文摘AIM:To support probe-based confocal laser endomi-croscopy (pCLE) diagnosis by designing software for the automated classification of colonic polyps. METHODS:Intravenous fluorescein pCLE imaging of colorectal lesions was performed on patients under-going screening and surveillance colonoscopies, followed by polypectomies. All resected specimens were reviewed by a reference gastrointestinal pathologist blinded to pCLE information. Histopathology was used as the criterion standard for the differentiation between neoplastic and non-neoplastic lesions. The pCLE video sequences, recorded for each polyp, were analyzed off-line by 2 expert endoscopists who were blinded to the endoscopic characteristics and histopathology. These pCLE videos, along with their histopathology diagnosis, were used to train the automated classification software which is a content-based image retrieval technique followed by k-nearest neighbor classification. The performance of the off-line diagnosis of pCLE videos established by the 2 expert endoscopists was compared with that of automated pCLE software classification. All evaluations were performed using leave-one-patient- out cross-validation to avoid bias. RESULTS:Colorectal lesions (135) were imaged in 71 patients. Based on histopathology, 93 of these 135 lesions were neoplastic and 42 were non-neoplastic. The study found no statistical significance for the difference between the performance of automated pCLE software classification (accuracy 89.6%, sensitivity 92.5%, specificity 83.3%, using leave-one-patient-out cross-validation) and the performance of the off-line diagnosis of pCLE videos established by the 2 expert endoscopists (accuracy 89.6%, sensitivity 91.4%, specificity 85.7%). There was very low power (< 6%) to detect the observed differences. The 95% confidence intervals for equivalence testing were:-0.073 to 0.073 for accuracy, -0.068 to 0.089 for sensitivity and -0.18 to 0.13 for specificity. The classification software proposed in this study is not a "black box" but an informative tool based on the query by example model that produces, as intermediate results, visually similar annotated videos that are directly interpretable by the endoscopist. CONCLUSION:The proposed software for automated classification of pCLE videos of colonic polyps achieves high performance, comparable to that of off-line diagnosis of pCLE videos established by expert endoscopists.
基金supported by a grant from the PLA Program for Clinical High-tech Projects for Military Hospitals (No. 2010GXJS053)
文摘China-made 5-axis simultaneous contouring CNC machine tool and domestically developed industrial computer-aided manufacture (CAM) technology were used for full crown fabrication and measurement of crown accuracy, with an attempt to establish an open CAM system for dental processing and to promote the introduction of domestic dental computer-aided design (CAD)/CAM system. Commercially available scanning equipment was used to make a basic digital tooth model after preparation of crown, and CAD software that comes with the scanning device was employed to design the crown by using domestic industrial CAM software to process the crown data in order to generate a solid model for machining purpose, and then China-made 5-axis simultaneous contouring CNC machine tool was used to complete machining of the whole crown and the internal accuracy of the crown internal was measured by using 3D-MicroCT. The results showed that China-made 5-axis simultaneous contouring CNC machine tool in combination with domestic industrial CAM technology can be used for crown making and the crown was well positioned in die. The internal accuracy was successfully measured by using 3D-MicroCT. It is concluded that an open CAM system for den-tistry on the basis of China-made 5-axis simultaneous contouring CNC machine tool and domestic industrial CAM software has been established, and development of the system will promote the introduction of domestically-produced dental CAD/CAM system.
基金supported by National Natural Science Foundation of China(Grant Nos.52235008,U2037203,and U2341270)Key Research and Development Plan of Hubei Province(2022BAA030).
文摘Additive manufacturing(AM)technology enables the creation of a wide variety of assemblies and complex shapes from three-dimensional model data in a bottom-up,layer-by-layer manner.Therefore,AM has revolutionized the modern manufacturing industry,attracting increasing interest from both academic and industrial fields.The Rapid Manufacturing Center(RMC)of the School of Materials Science and Engineering at the Huazhong Univer-sity of Science and Technology(HUST),one of the earliest and most powerful AM research teams in China,has been engaged in AM research since 1991.Aiming to address the“stuck neck”problems of specific high-strength products for AM,the RMC has conducted full-chain research in the aspects of special materials,processes,equip-ment,and applications for AM.Moreover,it has formed a multi-disciplinary research team over the past three decades.Relevant research achievements in the AM field include winning five national awards,more than ten first prizes,and more than ten second prizes at the provincial and ministerial levels.The RMC was complimented as“the world’s most influential organization in the laser AM field in 2018”by Virtual and Physical Prototyping(an international authoritative magazine of AM).Moreover,their industrialization achievements were evaluated as“having affected countries such as Singapore,South Korea,and the United States”by an international author-itative Wohlers Report on AM.In this study,we first summarize the representative research achievements of the RMC in the AM field.These include the preparation and processing technology of high-performance polymeric,metallic,and ceramic materials for AM;advanced processing technology and software/equipment for AM;and typical AM-fabricated products and their applications.Further,we discuss the latest research achievements in cutting-edge 4D printing in terms of feedstock selection,printing processes,induction strategies,and potential ap-plications.Finally,we provide insights into the future directions of AM technology development:(ⅰ)Evolving from three-dimensional printing to multi-dimensional printing,(ⅱ)transitioning from plane slicing to curved surface slicing to woven slicing,(ⅲ)enhancing efficient formation from dot-line-sheet-volume printing,(ⅳ)shifting from single material to multi-materials AM,(ⅴ)advancing from the multiscale direction of macroscopic-mesoscopic-microscopic structures,(ⅵ)integrating material preparation with forming integration,(ⅶ)expanding from small batch to large batch.
基金supported by National Natural Science Foundation of China(Grant No.50875090,Grant No.50905063)National Hi-tech Research and Development Program of China(863 Program,Grant No.2009AA4Z111)China Postdoctoral Science Foundation (Grant No.20090460769)
文摘The software-based computer numerical control(CNC) system includes three types of tasks: periodic real-time tasks, aperiodic real-time tasks, and non-real-time tasks. The tasks are characterized by concurrency, hybridization, and correlation, which make system implementation difficult. The conventional scheduling algorithm can not meet the demands of system implementation in the software-based CNC system completely. The uncertainty factors when running real-time tasks affect control performance by degrading manufacturing accuracy as a result of system resource and processor use restrictions. To address the technical difficulty of embedded system implementation, a novel fuzzy feedback scheduling algorithm based on output jitter of key real-time tasks for a software-based CNC system is proposed. Time characteristics, such as sampling jitter, input-output jitter, and non-schedulability are discussed, followed by quantification through simulations of the impact of time characteristics on manufacturing accuracy. On the basis of this research, the scheduler architecture is designed, and then the algorithm table is calculated. When the system resource changes, the key periodic real-time tasks meet their deadlines by means of dynamically adjusting the task period. The simulated results show that the machining precision rises by an order of magnitude for the proposed scheduler in resource-constrained software-based CNC systems. Moreover, unlike conventional feedback scheduling methods, the algorithm in this paper does not rely on the availability of task execution times and is easy to implement while incurring only a small overhead.
文摘Aim: To establish a rat and mouse epididymal map based on the use of the Epiquatre automatic software for histologic image analysis. Methods: Epididymides from five adult rats and five adult mice were fixed in alcoholic Bouin's fixative and embedded in paraffin. Serial longitudinal sections through the medial aspect of the organ were cut at 10 jam and stained with hematoxylin and eosin. As determined from major connective tissue septa, nine subdivisions of the rat epididymis and seven for the mouse were determined, consisting of five sub-regions in the caput (rat and mouse), one (mouse) or three (rat) in the corpus and one in the cauda (rat and mouse). Using the Epiquatre software, several tubular, luminal and epithelial morphometric parameters were evaluated. Results: Statistical comparison of the quantitative parameters revealed regional differences (2-5 in the rat, 3-6 in the mouse, dependent on parameters) with caput regions 1 and 2 being largely distinguishable from the similar remaining caput and corpus, which were in turn recognizable from the cauda regions in both species. Conclusion: The use of the Epiquatre software allowed us to establish regression curves for different morphometric parameters that can permit the detection of changes in their values under different pathological or experimental conditions. (Asian J Androl 2005 Sep; 7: 267-275)
文摘Custom-made esthetic finger prostheses, which are used for rehabilitation of patients with missing or impaired fingers, have been fabricated manually. However, such fabrication is time-consuming and requires manual skill. Here we propose a computer-aided method for fabricating finger pros-theses to save time and allow fabrications that do not require considerable manual skill. In this method, the dimensions of a patient’s healthy finger on the contralateral hand are first measured using a caliper. Using these dimensions, a three-dimensional model is constructed for fabricating a prosthesis for the patient’s impaired finger. Using the 3D model, a mold is designed using 3D modeling tools and a computer-aided design system. The resulting mold is then fabricated using a 3D printer. A finger prosthesis is fabricated by pouring silicone resin into the mold. A finger prosthesis for a volunteer was experimentally fabricated according to the proposed method. To evaluate the size and shape of the finger prosthesis, the difference between the finger prosthesis and the original finger of the volunteer was analyzed. Because the average difference between them was 0.25 mm, it was concluded that the proposed method could be used to fabricate a finger prosthesis of adequate size and shape.
文摘A method for designing real-time distributed controllers of discrete manufacturing systems is presented. The approach held is agent based;the controller strategy is distributed into several interacting agents that operate each one on a part of the manufacturing process;these agents may be distributed into several interconnected processors. The proposed method consists of a modelling methodology and software development framework that provides a generic agent architecture and communication facilities supporting the interaction among agents.
文摘At this stage, with the improvement of social living standards, as well as the rapid development of new science and technology, computer has become an indispensable new technology in the market economy environment and people's work and life, and the National Research on the computer industry is gradually strengthened. Driven by the computer industry, the economic benefits of various industries have been greatly improved. At present, computer-aided technology is mainly used in mechanical design and manufacturing. The application of this technology can greatly improve the work efficiency of mechanical design and manufacturing, ensure the design and manufacturing quality of various parts, meet people's demand standards, and create better development space for enterprises.The combination of computer-aided technology and mechanical design and manufacturing is an inevitable trend of the times, and also an important choice to create social and economic benefits.