Currently, simultaneously ensuring the machining accuracy and efficiency of thin-walled structures especially high performance parts still remains a challenge. Existing compensating methods are mainly focusing on 3-ai...Currently, simultaneously ensuring the machining accuracy and efficiency of thin-walled structures especially high performance parts still remains a challenge. Existing compensating methods are mainly focusing on 3-aixs machining, which sometimes only take one given point as the compensative point at each given cutter location. This paper presents a redesigned surface based machining strategy for peripheral milling of thin-walled parts. Based on an improved cutting force/heat model and finite element method（FEM） simulation environment, a deflection error prediction model, which takes sequence of cutter contact lines as compensation targets, is established. And an iterative algorithm is presented to determine feasible cutter axis positions. The final redesigned surface is subsequently generated by skinning all discrete cutter axis vectors after compensating by using the proposed algorithm. The proposed machining strategy incorporates the thermo-mechanical coupled effect in deflection prediction, and is also validated with flank milling experiment by using five-axis machine tool. At the same time, the deformation error is detected by using three-coordinate measuring machine. Error prediction values and experimental results indicate that they have a good consistency and the proposed approach is able to significantly reduce the dimension error under the same machining conditions compared with conventional methods. The proposed machining strategy has potential in high-efficiency precision machining of thin-walled parts.展开更多
Human noroviruses(HuNoVs)are major foodborne pathogens that cause nonbacterial acute gastroenteritis worldwide.As the tissue-culture system for HuNoVs is not mature enough for routine detection of the virus,detection ...Human noroviruses(HuNoVs)are major foodborne pathogens that cause nonbacterial acute gastroenteritis worldwide.As the tissue-culture system for HuNoVs is not mature enough for routine detection of the virus,detection is mainly dependent on molecular approaches such as reverse transcription polymerase chain reaction(RT-PCR)and reverse transcription quantitative real-time polymerase chain reaction(RTqPCR).The widely used primers and probes for RT-qPCR were established in the early 2000s.As HuNoVs are highly variant viruses,viral genome mutations result in previously designed primers and/or probes that were perfectly matched working less efficiently over time.In this study,a new duplex RT-qPCR(ND-RT-qPCR)was designed for the detection of genogroup Ⅰ(GⅠ)and genogroup Ⅱ(GⅡ)HuNoVs based on an analysis of viral sequences added in the database after 2010.Using long transcribed viral RNAs,the results demonstrate that the sensitivity of ND-RT-qPCR is as low as one genomic copy for both GⅠ and GⅡ HuNoVs.The performance of ND-RT-qPCR was further evaluated by a comparison with the commonly used Kageyama primer/probe sets for RT-qPCR(Kageyama RT-qPCR)for 23 HuNoV-positive clinical samples.All five GⅠ samples were registered as positive by ND-RT-qPCR,whereas only two samples were registered as positive by Kageyama RT-qPCR.All 18 GⅡ samples were registered as positive by ND-RT-qPCR,while 17 samples were registered as positive by Kageyama RT-qPCR.The sensitivity reflected by the quantification cycle(Cq)value was lower in ND-RT-qPCR than in Kageyama RT-qPCR.Our data suggest that ND-RT-qPCR could be a good fit for the detection of current strains of HuNoVs.展开更多
Biotechnological strategies for plastic depolymerization and recycling have emerged as transformative approaches to combat the global plastic pollution crisis,aligning with the principles of a sustainable and circular...Biotechnological strategies for plastic depolymerization and recycling have emerged as transformative approaches to combat the global plastic pollution crisis,aligning with the principles of a sustainable and circular economy.Despite advances in engineering PET hydrolases,the degradation process is frequently compromised by product inhibition and the heterogeneity of final products,thereby obstructing subsequent PET recondensation and impeding the synthesis of high-value derivatives.In this work,we utilized previously devised computational strategies to redesign a thermostable DuraMHETase,achieving an apparent melting temperature of 72℃ in complex with MHET and a 6-fold higher in total turnover number(TTN)toward MHET than the wild-type enzyme at 60℃.The fused enzyme system composed of DuraMHETase and TurboPETase demonstrated higher efficiency than other PET hydrolases and the separated dual enzyme systems.Furthermore,we identified both exo-and endo-PETase activities in DuraMHETase,whereas the endo-activity was previously unobserved at ambient temperatures.These results expand the functional scope of MHETase beyond mere intermediate hydrolysis,and may provide guidance for the development of more synergistic approaches to plastic biodepolymerization and recycling.展开更多
As an important part of the new generation of information technology,the Internet of Things(IoT)has been widely concerned and regarded as an enabling technology of the next generation of health care system.The fundus ...As an important part of the new generation of information technology,the Internet of Things(IoT)has been widely concerned and regarded as an enabling technology of the next generation of health care system.The fundus photography equipment is connected to the cloud platform through the IoT,so as to realize the realtime uploading of fundus images and the rapid issuance of diagnostic suggestions by artificial intelligence.At the same time,important security and privacy issues have emerged.The data uploaded to the cloud platform involves more personal attributes,health status and medical application data of patients.Once leaked,abused or improperly disclosed,personal information security will be violated.Therefore,it is important to address the security and privacy issues of massive medical and healthcare equipment connecting to the infrastructure of IoT healthcare and health systems.To meet this challenge,we propose MIA-UNet,a multi-scale iterative aggregation U-network,which aims to achieve accurate and efficient retinal vessel segmentation for ophthalmic auxiliary diagnosis while ensuring that the network has low computational complexity to adapt to mobile terminals.In this way,users do not need to upload the data to the cloud platform,and can analyze and process the fundus images on their own mobile terminals,thus eliminating the leakage of personal information.Specifically,the interconnection between encoder and decoder,as well as the internal connection between decoder subnetworks in classic U-Net are redefined and redesigned.Furthermore,we propose a hybrid loss function to smooth the gradient and deal with the imbalance between foreground and background.Compared with the UNet,the segmentation performance of the proposed network is significantly improved on the premise that the number of parameters is only increased by 2%.When applied to three publicly available datasets:DRIVE,STARE and CHASE DB1,the proposed network achieves the accuracy/F1-score of 96.33%/84.34%,97.12%/83.17%and 97.06%/84.10%,respectively.The experimental results show that the MIA-UNet is superior to the state-of-the-art methods.展开更多
对中国品牌形象的国际化设计进行研究。用视觉人种志的研究方法,通过笔者在欧洲市场对中国品牌的形象设计现状进行研究,得出经济全球化、信息全球化的背景下,中国品牌进入全球市场,要实现品牌价值的提升,从而达到"Made in china&qu...对中国品牌形象的国际化设计进行研究。用视觉人种志的研究方法,通过笔者在欧洲市场对中国品牌的形象设计现状进行研究,得出经济全球化、信息全球化的背景下,中国品牌进入全球市场,要实现品牌价值的提升,从而达到"Made in china"到"Design in china"的目的,在这个过程中,视觉传达设计到了很重要的作用。有效提升中国品牌形象设计的方法是对品牌名称进行翻译和对品牌形象进行Redesign。在当代视觉审美语境下,品牌形象的视觉传达设计应将中国审美与西方审美相融合,最终实现品牌形象的国际化设计。展开更多
The paper investigates the learner-focused English as a Foreign Langue(EFL) curricular innovation in China Agricultural University(referred to as CAU in the following text) from the perspectives of curricular formulat...The paper investigates the learner-focused English as a Foreign Langue(EFL) curricular innovation in China Agricultural University(referred to as CAU in the following text) from the perspectives of curricular formulation,implementation and evaluation of EFL learning & teaching in the one-year duration from Autumn semester of 2016 to Spring semester of 2017.A discussion of the effects of the curricular restructuring is presented.展开更多
Many design engineers in cross-domain industries have attended training classes of TRIZ to improve their innovative abilities in China. Most of them are successful, but others are not. So the latest target of the trai...Many design engineers in cross-domain industries have attended training classes of TRIZ to improve their innovative abilities in China. Most of them are successful, but others are not. So the latest target of the trainers is to improve the training process used now in industry in China and to make the engineers to understand the basic principles of TRIZ better. Based on the mass-engineer-oriented training model(MEOTM) and mechanical engineers’ design cases, a relationship between managing activities about the opportunities for innovation and the training process is set up. It is shown that the inventive problems come first from opportunity searching for engineers. A training and gate system for evaluation is developed to involve the managing activities of the companies in the training process. Then comparison between the general analogous process and the application of TRIZ is made, which shows the advantages and depth principles of TRIZ for the engineers to apply them confidently. Lastly a new process is formed in which opportunity searching, engineers training, inventive problems identifying and solving,and three redesign paths are connected seamlessly. The research proposes an opportunity-driven redesign path that cooperates the training and opportunity searching, which will be applied in future training classes to make more and more engineers to follow.展开更多
According to the reliable data of sixteen CNC lathes, each reliable index of the serial CNC lathes is evaluated before tackling and after tackling. According to the failure analysis, reliable improvement measures of t...According to the reliable data of sixteen CNC lathes, each reliable index of the serial CNC lathes is evaluated before tackling and after tackling. According to the failure analysis, reliable improvement measures of the serial CNC lathes are put forward.展开更多
A robust unified controller was proposed for wheeled mobile robots that do not satisfy the ideal rolling without slipping constraint.Practical trajectory tracking and posture stabilization were achieved in a unified f...A robust unified controller was proposed for wheeled mobile robots that do not satisfy the ideal rolling without slipping constraint.Practical trajectory tracking and posture stabilization were achieved in a unified framework.The design procedure was based on the transverse function method and Lyapunov redesign technique.The Lie group was also introduced in the design.The left-invariance property of the nominal model was firstly explored with respect to the standard group operation of the Lie group SE(2).Then,a bounded transverse function was constructed,by which a corresponding smooth embedded submanifold was defined.With the aid of the group operation,a smooth control law was designed,which fulfills practical tracking/stabilization of the nominal system.An additional component was finally constructed to robustify the nominal control law with respect to the slipping disturbance by using the Lyapunov redesign technique.The design procedure can be easily extended to the robot system suffered from general unknown but bounded disturbances.Simulations were provided to demonstrate the effectiveness of the robust unified controller.展开更多
One of the founders of structural control theory and its application in civil engineering, Professor Emeritus Tsu T. Soong, envisioned the development of the integral design of structures protected by active control d...One of the founders of structural control theory and its application in civil engineering, Professor Emeritus Tsu T. Soong, envisioned the development of the integral design of structures protected by active control devices. Most of his disciples and colleagues continuously attempted to develop procedures to achieve such integral control. In his recent papers published jointly with some of the authors of this paper, Professor Soong developed design procedures for the entire structure using a design - redesign procedure applied to elastic systems. Such a procedure was developed as an extension of other work by his disciples. This paper summarizes some recent techniques that use traditional active control algorithms to derive the most suitable （optimal, stable） control force, which could then be implemented with a combination of active, passive and semi-active devices through a simple match or more sophisticated optimal procedures. Alternative design can address the behavior of structures using Liapunov stability criteria. This paper shows a unified procedure which can be applied to both elastic and inelastic structures. Although the implementation does not always preserve the optimal criteria, it is shown that the solutions are effective and practical for design of supplemental damping, stiffness enhancement or softening, and strengthening or weakening.展开更多
This paper presents a real-time mechanism to tolerate faults occurring in a wind turbine （WT） system. This system is composed of a FAST coded simulator designed by the U.S. National Renewable Energy Laboratory. The ...This paper presents a real-time mechanism to tolerate faults occurring in a wind turbine （WT） system. This system is composed of a FAST coded simulator designed by the U.S. National Renewable Energy Laboratory. The demonstrated mechanism lies under the taxonomy of active fault-tolerant control （FTC） systems, namely online redesign based approach. In the proposed approach, we do not use any a priori information about the model of the turbine in real-time. In fact, we use online measurements generated by the WT. Based on the given control specifications, and the observed measurement an occurred fault is accommodated by reconfiguring the online controller such that the WT generates rated power even under faulty conditions. Second, no explicit fault diagnosis （FD） module is used in this approach. As a result, issues of model uncertainty, false alarms, etc. associated with an integrated FD and controller reconfiguration approach to FTC systems are not experienced here.展开更多
A certain number of railway brake discs made of gray cast iron,showed the presence of small cracks only after a few thousand kilometers.To investigate main causes of a brake disc failure,numerical analysis was done by...A certain number of railway brake discs made of gray cast iron,showed the presence of small cracks only after a few thousand kilometers.To investigate main causes of a brake disc failure,numerical analysis was done by using ABAQUS software.Numerical analysis resulted from a physical model of heat flux in dependence of braking time.Physical model was applied considering all demands and presumptions given by industry representatives.展开更多
The rapid development of urbanization and rapid growth of urban population have brought about various urban problems, and the development of cities to the ground and underground has become an inevitable choice. Underg...The rapid development of urbanization and rapid growth of urban population have brought about various urban problems, and the development of cities to the ground and underground has become an inevitable choice. Underground street is a kind of underground space types, and it is also an important urban recreational resources and tourism resources. The evaluation of underground street users, especially the residents and tourists, has important reference value for the recreational resources’ redevelopment of underground street. Firstly, this paper reviews the relevant research literature on underground street and Post-Occupancy Evaluation theory, then chooses Diyi Underground Street, Chengdu, China, as the research object, and conducts a questionnaire survey and in-depth interviews on residents’ shopping intention from five dimensions of underground street environment, decoration, commercial form, public facilities and other aspects. Finally, the survey data are analyzed quantitatively. The results show that some influence factors such as air quality, daylighting, decoration style etc. greatly affect the willingness of residents to enter the street. Therefore, residents’ recreational experience should be emphasized during the underground street re-planning according to the above factors.展开更多
In improving the competitiveness of business organi sa tion in the 21st century, minimising cost and increasing productivity are no lon ger factors that could promise the success. The changes in customer trends whic h...In improving the competitiveness of business organi sa tion in the 21st century, minimising cost and increasing productivity are no lon ger factors that could promise the success. The changes in customer trends whic h focusing more on product or service customising, high quality and short delive ry times are additional crucial factors that organisation should be aware of. T hese factors have direct relations on how the management could utilise the capab ility of its supply chain management (SCM). The importance of SCM in organisati on specifically to manufacturer is to play a vital role in managing the flow of material and information along the chain from suppliers to customers. In a trad itional way, SCM is mainly manage by the production department in organisation b ut with the advancement in information technology, resulted the changes in worki ng environment. One of the ways that could be implemented in decision making p rocess in order to improve the effectiveness and efficiency of the decision is t hrough collaborative environment. Due to this situation, there is a need to rede sign the existing SCM in order to optimise its capability and functionality in t he way to ensure the organisation competitiveness is sustainable. A minor or ma jor alignment to SCM business processes should be done in order to streamline th e flow of information, which could also affect the flow of materials. Factors s uch as SCM operational, structural and even its managerial are among the issues that are critical in redesigning its business process. Each of these factors has its own attributes such as lead-times, complexity, frequency and organisationa l setting that could lead in improving organisational competitiveness. In additi on, by identifying these factors, it would help the management to plan and desig n the collaborative SCM that would effectively correspond to the changes in busi ness and customer trends. The intention of the paper is to promote a list of fa ctors and attributes, which are critical in redesigning an existing SCM in order to shift its environment to become collaborative SCM. By utilising these facto rs and attributes, a model for redesigning SCM into collaborative environment is currently developed by the author and will be used in the next stage of his res earch.展开更多
Horizontal press as an important part of hydro-forming machine is used to output the horizontal force to keep the high internal pressure during tube hydro-forming. However,the horizontal press frame is usually mounted...Horizontal press as an important part of hydro-forming machine is used to output the horizontal force to keep the high internal pressure during tube hydro-forming. However,the horizontal press frame is usually mounted on the press bed and not pre-stressed. Meanwhile it will be subjected to the reaction force caused by liquid pressure. Stresses are concentrated severely on the assemble region due to deformation,and total fatigue life will decrease. In order to predict the total fatigue life of the frame,the simulations are used firstly to determine to stress concentration region,and then strain gauge measurements are carried out under different loads. Next,the methods of statistical probability are conducted to calculate the fatigue life based on long-term load history. Finally a structure with the considerable longer fatigue life is redesigned.展开更多
In order to overcome stress concentration and increase fatigue life of ellipsoidal shells with inner guide structure,the stress analysis for strength check is very important. Owing to the main sectional profile with e...In order to overcome stress concentration and increase fatigue life of ellipsoidal shells with inner guide structure,the stress analysis for strength check is very important. Owing to the main sectional profile with ellipsoidal shape,the stress distribution for perfect ellipsoidal shell is firstly conducted based on the theoretical calculation and strain gauges measurement. The experiment results show that the stresses increase gradually from pole region to equatorial plane,but still within elastic range. Secondly,strain gauge measurement for ellipsoidal shells with inner guide structure is conducted. The results show that stresses are concentrated at the vicinity of bottom plate and beyond elastic range,so the structural redesign is needed. Finally based on the analysis mentioned above,a redesigned structure with local thickening is proposed. Experimental research shows that the stress varies more even after structural redesign and within allowable range. Numerical simulation shows that both the deformation and fatigue life after redesign are acceptable.展开更多
Modular structure reengineering is a design approach conforming to the mobile exhibition features in nature and giving full play to the flexibility,convenience,and environmental protection of the mobile exhibition mod...Modular structure reengineering is a design approach conforming to the mobile exhibition features in nature and giving full play to the flexibility,convenience,and environmental protection of the mobile exhibition modes. The objective of this paper on modular reengineering study is to analyze the innovative applications of modular design in small mobile exhibition. Firstly,the modular design in the domestic small mobile exhibition was investigated in this paper,and then the significance of modular design in small mobile exhibition was proposed via combining the design and future orientation of small mobile exhibition modes. The conclusion is that modular multi-functional small mobile exhibition is the inevitable direction of the future development of the exhibition industry,as this design mode solves a series of problems including resources intensification,structure rationalization,and cost reduction in a foreseeable scope to facilitate sufficient utilization and development of the small mobile exhibition modes.展开更多
The inverse design method of a dynamic system with linear parameters has been studied. For some specified eigenvalues and eigenvectors, the design parameter vector which is often composed of whole or part of coefficie...The inverse design method of a dynamic system with linear parameters has been studied. For some specified eigenvalues and eigenvectors, the design parameter vector which is often composed of whole or part of coefficients of spring and mass of the system can be obtained and the rigidity and mass matrices of an initially designed structure can be reconstructed through solving linear algebra equations. By using implicit function theorem, the conditions of existence and uniqueness of the solution are also deduced. The theory and method can be used for inverse vibration design of complex structure system.展开更多
The particular characteristics of Rapid Prototyping technologies, both in terms of constrains and opportunities, often require the reconfiguration of the product model to obtain the best compliance with the product fu...The particular characteristics of Rapid Prototyping technologies, both in terms of constrains and opportunities, often require the reconfiguration of the product model to obtain the best compliance with the product functionalities and performances. Within this field of research, a knowledge-based tool named Design GuideLines Collaborative Framework (DGLs-CF) was developed to support both the designers defining the product consistently with the manufacturing technologies and the manufacturers defining the building setup consistently with the product requirements. Present work is focused on enhancing the DGLs-CF knowledge base and on updating the DGLs-CF knowledge management by using the information gathered on some RP technologies. The added-value of this research is represented by an improvement in the Redesign/Reconfig- uration Package, the final result of the DGLs-CF adoption. This is a list of actions to be performed on the product model and on the process parameters to avoid the limitations of the technology and to exploit at best its opportunities.展开更多
At present, whether internally or abroad, whether in the theory or business, there is a lack of a unified understanding about the basic concepts of structural system and theoretical category of enterprise business mod...At present, whether internally or abroad, whether in the theory or business, there is a lack of a unified understanding about the basic concepts of structural system and theoretical category of enterprise business model, and its theoretical analysis framework has not been built up, it is the exploratory phase of the model research in the mass. This study aims to analyze the formation mechanism, action mechanism, and evolution mechanism about the business model from the perspective of structure, and designs the enterprise business model architecture and forms a system, besides, explores approaches and strategies about enterprise carrying out business model innovation, and does beneficial bedding in order to use and improve the theoretical system in the process of the enterprise management practice. The significance of this study is to provide analytical methods and tools for the business model questions in the enterprise management practice. This paper firstly defined the connotation of enterprise business model and summarized the seven characteristics of the corporate business model. On the basis of outlining the enterprise business model design theory, the structural design of the corporate business model is mainly discussed. This paper designed the structure of the business model on modular perspective, proposed four constituent units and nine elements of enterprise business model structure system. Through the design of the enterprise business model structure and analysis of the elements that constitute structure, provide the basis for the transformation of innovative enterprise business model, or both enterprise business models, avoid the lack of elements of the enterprise business model structure and lead to business failure. Finally, the paper concludes with the five core strategies for the implementation of the enterprise business model design.展开更多
基金supported by Key Program of National Natural Science Foundation of China (Grant No. 50835001) General Program of National Natural Science Foundation of China (Grant No. 50775023)Program for New Century Excellent Talents of Ministry of Education of China (Grant No. NCET-08-081)
文摘Currently, simultaneously ensuring the machining accuracy and efficiency of thin-walled structures especially high performance parts still remains a challenge. Existing compensating methods are mainly focusing on 3-aixs machining, which sometimes only take one given point as the compensative point at each given cutter location. This paper presents a redesigned surface based machining strategy for peripheral milling of thin-walled parts. Based on an improved cutting force/heat model and finite element method（FEM） simulation environment, a deflection error prediction model, which takes sequence of cutter contact lines as compensation targets, is established. And an iterative algorithm is presented to determine feasible cutter axis positions. The final redesigned surface is subsequently generated by skinning all discrete cutter axis vectors after compensating by using the proposed algorithm. The proposed machining strategy incorporates the thermo-mechanical coupled effect in deflection prediction, and is also validated with flank milling experiment by using five-axis machine tool. At the same time, the deformation error is detected by using three-coordinate measuring machine. Error prediction values and experimental results indicate that they have a good consistency and the proposed approach is able to significantly reduce the dimension error under the same machining conditions compared with conventional methods. The proposed machining strategy has potential in high-efficiency precision machining of thin-walled parts.
基金supported by the Ministry of Science and Technology of China(2017YFC1601200)the National Natural Science Foundation of China(31772078)the Agri-X Interdisciplinary Fund of Shanghai Jiao Tong University(2017).
文摘Human noroviruses(HuNoVs)are major foodborne pathogens that cause nonbacterial acute gastroenteritis worldwide.As the tissue-culture system for HuNoVs is not mature enough for routine detection of the virus,detection is mainly dependent on molecular approaches such as reverse transcription polymerase chain reaction(RT-PCR)and reverse transcription quantitative real-time polymerase chain reaction(RTqPCR).The widely used primers and probes for RT-qPCR were established in the early 2000s.As HuNoVs are highly variant viruses,viral genome mutations result in previously designed primers and/or probes that were perfectly matched working less efficiently over time.In this study,a new duplex RT-qPCR(ND-RT-qPCR)was designed for the detection of genogroup Ⅰ(GⅠ)and genogroup Ⅱ(GⅡ)HuNoVs based on an analysis of viral sequences added in the database after 2010.Using long transcribed viral RNAs,the results demonstrate that the sensitivity of ND-RT-qPCR is as low as one genomic copy for both GⅠ and GⅡ HuNoVs.The performance of ND-RT-qPCR was further evaluated by a comparison with the commonly used Kageyama primer/probe sets for RT-qPCR(Kageyama RT-qPCR)for 23 HuNoV-positive clinical samples.All five GⅠ samples were registered as positive by ND-RT-qPCR,whereas only two samples were registered as positive by Kageyama RT-qPCR.All 18 GⅡ samples were registered as positive by ND-RT-qPCR,while 17 samples were registered as positive by Kageyama RT-qPCR.The sensitivity reflected by the quantification cycle(Cq)value was lower in ND-RT-qPCR than in Kageyama RT-qPCR.Our data suggest that ND-RT-qPCR could be a good fit for the detection of current strains of HuNoVs.
文摘Biotechnological strategies for plastic depolymerization and recycling have emerged as transformative approaches to combat the global plastic pollution crisis,aligning with the principles of a sustainable and circular economy.Despite advances in engineering PET hydrolases,the degradation process is frequently compromised by product inhibition and the heterogeneity of final products,thereby obstructing subsequent PET recondensation and impeding the synthesis of high-value derivatives.In this work,we utilized previously devised computational strategies to redesign a thermostable DuraMHETase,achieving an apparent melting temperature of 72℃ in complex with MHET and a 6-fold higher in total turnover number(TTN)toward MHET than the wild-type enzyme at 60℃.The fused enzyme system composed of DuraMHETase and TurboPETase demonstrated higher efficiency than other PET hydrolases and the separated dual enzyme systems.Furthermore,we identified both exo-and endo-PETase activities in DuraMHETase,whereas the endo-activity was previously unobserved at ambient temperatures.These results expand the functional scope of MHETase beyond mere intermediate hydrolysis,and may provide guidance for the development of more synergistic approaches to plastic biodepolymerization and recycling.
基金This work was supported in part by the National Natural Science Foundation of China(Nos.62072074,62076054,62027827,61902054)the Frontier Science and Technology Innovation Projects of National Key R&D Program(No.2019QY1405)+2 种基金the Sichuan Science and Technology Innovation Platform and Talent Plan(No.2020JDJQ0020)the Sichuan Science and Technology Support Plan(No.2020YFSY0010)the Natural Science Foundation of Guangdong Province(No.2018A030313354).
文摘As an important part of the new generation of information technology,the Internet of Things(IoT)has been widely concerned and regarded as an enabling technology of the next generation of health care system.The fundus photography equipment is connected to the cloud platform through the IoT,so as to realize the realtime uploading of fundus images and the rapid issuance of diagnostic suggestions by artificial intelligence.At the same time,important security and privacy issues have emerged.The data uploaded to the cloud platform involves more personal attributes,health status and medical application data of patients.Once leaked,abused or improperly disclosed,personal information security will be violated.Therefore,it is important to address the security and privacy issues of massive medical and healthcare equipment connecting to the infrastructure of IoT healthcare and health systems.To meet this challenge,we propose MIA-UNet,a multi-scale iterative aggregation U-network,which aims to achieve accurate and efficient retinal vessel segmentation for ophthalmic auxiliary diagnosis while ensuring that the network has low computational complexity to adapt to mobile terminals.In this way,users do not need to upload the data to the cloud platform,and can analyze and process the fundus images on their own mobile terminals,thus eliminating the leakage of personal information.Specifically,the interconnection between encoder and decoder,as well as the internal connection between decoder subnetworks in classic U-Net are redefined and redesigned.Furthermore,we propose a hybrid loss function to smooth the gradient and deal with the imbalance between foreground and background.Compared with the UNet,the segmentation performance of the proposed network is significantly improved on the premise that the number of parameters is only increased by 2%.When applied to three publicly available datasets:DRIVE,STARE and CHASE DB1,the proposed network achieves the accuracy/F1-score of 96.33%/84.34%,97.12%/83.17%and 97.06%/84.10%,respectively.The experimental results show that the MIA-UNet is superior to the state-of-the-art methods.
文摘对中国品牌形象的国际化设计进行研究。用视觉人种志的研究方法,通过笔者在欧洲市场对中国品牌的形象设计现状进行研究,得出经济全球化、信息全球化的背景下,中国品牌进入全球市场,要实现品牌价值的提升,从而达到"Made in china"到"Design in china"的目的,在这个过程中,视觉传达设计到了很重要的作用。有效提升中国品牌形象设计的方法是对品牌名称进行翻译和对品牌形象进行Redesign。在当代视觉审美语境下,品牌形象的视觉传达设计应将中国审美与西方审美相融合,最终实现品牌形象的国际化设计。
文摘The paper investigates the learner-focused English as a Foreign Langue(EFL) curricular innovation in China Agricultural University(referred to as CAU in the following text) from the perspectives of curricular formulation,implementation and evaluation of EFL learning & teaching in the one-year duration from Autumn semester of 2016 to Spring semester of 2017.A discussion of the effects of the curricular restructuring is presented.
基金Supported by National Natural Science Foundation of China(Grant Nos.51675159,51305123)
文摘Many design engineers in cross-domain industries have attended training classes of TRIZ to improve their innovative abilities in China. Most of them are successful, but others are not. So the latest target of the trainers is to improve the training process used now in industry in China and to make the engineers to understand the basic principles of TRIZ better. Based on the mass-engineer-oriented training model(MEOTM) and mechanical engineers’ design cases, a relationship between managing activities about the opportunities for innovation and the training process is set up. It is shown that the inventive problems come first from opportunity searching for engineers. A training and gate system for evaluation is developed to involve the managing activities of the companies in the training process. Then comparison between the general analogous process and the application of TRIZ is made, which shows the advantages and depth principles of TRIZ for the engineers to apply them confidently. Lastly a new process is formed in which opportunity searching, engineers training, inventive problems identifying and solving,and three redesign paths are connected seamlessly. The research proposes an opportunity-driven redesign path that cooperates the training and opportunity searching, which will be applied in future training classes to make more and more engineers to follow.
文摘According to the reliable data of sixteen CNC lathes, each reliable index of the serial CNC lathes is evaluated before tackling and after tackling. According to the failure analysis, reliable improvement measures of the serial CNC lathes are put forward.
基金Project (60234030) supported by the National Natural Science Foundation of ChinaProject supported by the TRAPOYT of Ministry of Education of China
文摘A robust unified controller was proposed for wheeled mobile robots that do not satisfy the ideal rolling without slipping constraint.Practical trajectory tracking and posture stabilization were achieved in a unified framework.The design procedure was based on the transverse function method and Lyapunov redesign technique.The Lie group was also introduced in the design.The left-invariance property of the nominal model was firstly explored with respect to the standard group operation of the Lie group SE(2).Then,a bounded transverse function was constructed,by which a corresponding smooth embedded submanifold was defined.With the aid of the group operation,a smooth control law was designed,which fulfills practical tracking/stabilization of the nominal system.An additional component was finally constructed to robustify the nominal control law with respect to the slipping disturbance by using the Lyapunov redesign technique.The design procedure can be easily extended to the robot system suffered from general unknown but bounded disturbances.Simulations were provided to demonstrate the effectiveness of the robust unified controller.
文摘One of the founders of structural control theory and its application in civil engineering, Professor Emeritus Tsu T. Soong, envisioned the development of the integral design of structures protected by active control devices. Most of his disciples and colleagues continuously attempted to develop procedures to achieve such integral control. In his recent papers published jointly with some of the authors of this paper, Professor Soong developed design procedures for the entire structure using a design - redesign procedure applied to elastic systems. Such a procedure was developed as an extension of other work by his disciples. This paper summarizes some recent techniques that use traditional active control algorithms to derive the most suitable （optimal, stable） control force, which could then be implemented with a combination of active, passive and semi-active devices through a simple match or more sophisticated optimal procedures. Alternative design can address the behavior of structures using Liapunov stability criteria. This paper shows a unified procedure which can be applied to both elastic and inelastic structures. Although the implementation does not always preserve the optimal criteria, it is shown that the solutions are effective and practical for design of supplemental damping, stiffness enhancement or softening, and strengthening or weakening.
文摘This paper presents a real-time mechanism to tolerate faults occurring in a wind turbine （WT） system. This system is composed of a FAST coded simulator designed by the U.S. National Renewable Energy Laboratory. The demonstrated mechanism lies under the taxonomy of active fault-tolerant control （FTC） systems, namely online redesign based approach. In the proposed approach, we do not use any a priori information about the model of the turbine in real-time. In fact, we use online measurements generated by the WT. Based on the given control specifications, and the observed measurement an occurred fault is accommodated by reconfiguring the online controller such that the WT generates rated power even under faulty conditions. Second, no explicit fault diagnosis （FD） module is used in this approach. As a result, issues of model uncertainty, false alarms, etc. associated with an integrated FD and controller reconfiguration approach to FTC systems are not experienced here.
文摘A certain number of railway brake discs made of gray cast iron,showed the presence of small cracks only after a few thousand kilometers.To investigate main causes of a brake disc failure,numerical analysis was done by using ABAQUS software.Numerical analysis resulted from a physical model of heat flux in dependence of braking time.Physical model was applied considering all demands and presumptions given by industry representatives.
文摘The rapid development of urbanization and rapid growth of urban population have brought about various urban problems, and the development of cities to the ground and underground has become an inevitable choice. Underground street is a kind of underground space types, and it is also an important urban recreational resources and tourism resources. The evaluation of underground street users, especially the residents and tourists, has important reference value for the recreational resources’ redevelopment of underground street. Firstly, this paper reviews the relevant research literature on underground street and Post-Occupancy Evaluation theory, then chooses Diyi Underground Street, Chengdu, China, as the research object, and conducts a questionnaire survey and in-depth interviews on residents’ shopping intention from five dimensions of underground street environment, decoration, commercial form, public facilities and other aspects. Finally, the survey data are analyzed quantitatively. The results show that some influence factors such as air quality, daylighting, decoration style etc. greatly affect the willingness of residents to enter the street. Therefore, residents’ recreational experience should be emphasized during the underground street re-planning according to the above factors.
文摘In improving the competitiveness of business organi sa tion in the 21st century, minimising cost and increasing productivity are no lon ger factors that could promise the success. The changes in customer trends whic h focusing more on product or service customising, high quality and short delive ry times are additional crucial factors that organisation should be aware of. T hese factors have direct relations on how the management could utilise the capab ility of its supply chain management (SCM). The importance of SCM in organisati on specifically to manufacturer is to play a vital role in managing the flow of material and information along the chain from suppliers to customers. In a trad itional way, SCM is mainly manage by the production department in organisation b ut with the advancement in information technology, resulted the changes in worki ng environment. One of the ways that could be implemented in decision making p rocess in order to improve the effectiveness and efficiency of the decision is t hrough collaborative environment. Due to this situation, there is a need to rede sign the existing SCM in order to optimise its capability and functionality in t he way to ensure the organisation competitiveness is sustainable. A minor or ma jor alignment to SCM business processes should be done in order to streamline th e flow of information, which could also affect the flow of materials. Factors s uch as SCM operational, structural and even its managerial are among the issues that are critical in redesigning its business process. Each of these factors has its own attributes such as lead-times, complexity, frequency and organisationa l setting that could lead in improving organisational competitiveness. In additi on, by identifying these factors, it would help the management to plan and desig n the collaborative SCM that would effectively correspond to the changes in busi ness and customer trends. The intention of the paper is to promote a list of fa ctors and attributes, which are critical in redesigning an existing SCM in order to shift its environment to become collaborative SCM. By utilising these facto rs and attributes, a model for redesigning SCM into collaborative environment is currently developed by the author and will be used in the next stage of his res earch.
基金Sponsored by the High-End CNC Machine Tools and Basic Manufacturing Equipment Technology Major Project(Grant No.2011ZX04001-011)
文摘Horizontal press as an important part of hydro-forming machine is used to output the horizontal force to keep the high internal pressure during tube hydro-forming. However,the horizontal press frame is usually mounted on the press bed and not pre-stressed. Meanwhile it will be subjected to the reaction force caused by liquid pressure. Stresses are concentrated severely on the assemble region due to deformation,and total fatigue life will decrease. In order to predict the total fatigue life of the frame,the simulations are used firstly to determine to stress concentration region,and then strain gauge measurements are carried out under different loads. Next,the methods of statistical probability are conducted to calculate the fatigue life based on long-term load history. Finally a structure with the considerable longer fatigue life is redesigned.
基金Spondored by the High-End CNC Machine Tools and Basic Manufacturing Equipment Technology Major Project(Grant No.2011ZX04001-011)
文摘In order to overcome stress concentration and increase fatigue life of ellipsoidal shells with inner guide structure,the stress analysis for strength check is very important. Owing to the main sectional profile with ellipsoidal shape,the stress distribution for perfect ellipsoidal shell is firstly conducted based on the theoretical calculation and strain gauges measurement. The experiment results show that the stresses increase gradually from pole region to equatorial plane,but still within elastic range. Secondly,strain gauge measurement for ellipsoidal shells with inner guide structure is conducted. The results show that stresses are concentrated at the vicinity of bottom plate and beyond elastic range,so the structural redesign is needed. Finally based on the analysis mentioned above,a redesigned structure with local thickening is proposed. Experimental research shows that the stress varies more even after structural redesign and within allowable range. Numerical simulation shows that both the deformation and fatigue life after redesign are acceptable.
文摘Modular structure reengineering is a design approach conforming to the mobile exhibition features in nature and giving full play to the flexibility,convenience,and environmental protection of the mobile exhibition modes. The objective of this paper on modular reengineering study is to analyze the innovative applications of modular design in small mobile exhibition. Firstly,the modular design in the domestic small mobile exhibition was investigated in this paper,and then the significance of modular design in small mobile exhibition was proposed via combining the design and future orientation of small mobile exhibition modes. The conclusion is that modular multi-functional small mobile exhibition is the inevitable direction of the future development of the exhibition industry,as this design mode solves a series of problems including resources intensification,structure rationalization,and cost reduction in a foreseeable scope to facilitate sufficient utilization and development of the small mobile exhibition modes.
基金Science Developing Plan of Beijing Educational Committee, Beijing Natural Science Fund (No. 3022003), and NationalNatural Science Fund of China(No.50375002)
文摘The inverse design method of a dynamic system with linear parameters has been studied. For some specified eigenvalues and eigenvectors, the design parameter vector which is often composed of whole or part of coefficients of spring and mass of the system can be obtained and the rigidity and mass matrices of an initially designed structure can be reconstructed through solving linear algebra equations. By using implicit function theorem, the conditions of existence and uniqueness of the solution are also deduced. The theory and method can be used for inverse vibration design of complex structure system.
文摘The particular characteristics of Rapid Prototyping technologies, both in terms of constrains and opportunities, often require the reconfiguration of the product model to obtain the best compliance with the product functionalities and performances. Within this field of research, a knowledge-based tool named Design GuideLines Collaborative Framework (DGLs-CF) was developed to support both the designers defining the product consistently with the manufacturing technologies and the manufacturers defining the building setup consistently with the product requirements. Present work is focused on enhancing the DGLs-CF knowledge base and on updating the DGLs-CF knowledge management by using the information gathered on some RP technologies. The added-value of this research is represented by an improvement in the Redesign/Reconfig- uration Package, the final result of the DGLs-CF adoption. This is a list of actions to be performed on the product model and on the process parameters to avoid the limitations of the technology and to exploit at best its opportunities.
文摘At present, whether internally or abroad, whether in the theory or business, there is a lack of a unified understanding about the basic concepts of structural system and theoretical category of enterprise business model, and its theoretical analysis framework has not been built up, it is the exploratory phase of the model research in the mass. This study aims to analyze the formation mechanism, action mechanism, and evolution mechanism about the business model from the perspective of structure, and designs the enterprise business model architecture and forms a system, besides, explores approaches and strategies about enterprise carrying out business model innovation, and does beneficial bedding in order to use and improve the theoretical system in the process of the enterprise management practice. The significance of this study is to provide analytical methods and tools for the business model questions in the enterprise management practice. This paper firstly defined the connotation of enterprise business model and summarized the seven characteristics of the corporate business model. On the basis of outlining the enterprise business model design theory, the structural design of the corporate business model is mainly discussed. This paper designed the structure of the business model on modular perspective, proposed four constituent units and nine elements of enterprise business model structure system. Through the design of the enterprise business model structure and analysis of the elements that constitute structure, provide the basis for the transformation of innovative enterprise business model, or both enterprise business models, avoid the lack of elements of the enterprise business model structure and lead to business failure. Finally, the paper concludes with the five core strategies for the implementation of the enterprise business model design.
