成立于1968年的意大利设计团队(DESIGN GROUP ITALIA),是一个涉及多领域的国际化设计机构,拥有一支文化背景不同但备有所长的设计精英团队。他们为多家国际大型企业成功提供了数个以消费者为中心的全方位设计解决方案,从产品到品...成立于1968年的意大利设计团队(DESIGN GROUP ITALIA),是一个涉及多领域的国际化设计机构,拥有一支文化背景不同但备有所长的设计精英团队。他们为多家国际大型企业成功提供了数个以消费者为中心的全方位设计解决方案,从产品到品牌,涵盖设计全流程。展开更多
Recently, the structural fuse has become an important issue in the field of earthquake engineering. Due to the trilinearity of the pushover curve of buildings with metallic structural fuses, the mechanism of the struc...Recently, the structural fuse has become an important issue in the field of earthquake engineering. Due to the trilinearity of the pushover curve of buildings with metallic structural fuses, the mechanism of the structural fuse is investigated through the ductility equation of a single-degree-of-freedom system, and the corresponding damage-reduction spectrum is proposed to design and retrofit buildings. Furthermore, the controlling parameters, the stiffness ratio between the main frame and structural fuse and the ductility factor of the main frame, are parametrically studied, and it is shown that the structural fuse concept can be achieved by specific combinations of the controlling parameters based on the proposed damage-reduction spectrum. Finally, a design example and a retrofit example, variations of real engineering projects after the 2008 Wenchuan earthquake, are provided to demonstrate the effectiveness of the proposed design procedures using buckling restrained braces as the structural fuses.展开更多
Beijing-Tianjin intercity railway is the first newly-built passenger dedicated line with operating speed of 350 km/h in our country. During design,new ideas of bridge construction were carried out to ensure the requir...Beijing-Tianjin intercity railway is the first newly-built passenger dedicated line with operating speed of 350 km/h in our country. During design,new ideas of bridge construction were carried out to ensure the requirements of safety,comfort and stability of the train under high-speed condition. At the same time,concepts of environmental adaptability,service to transportation and comprehensive benefits were observed. On the whole line,long-bridge schemes were adopted and the most advanced technologies of unballasted track were utilized on bridges,the length of which accounts for 87.7 % of the total line. The success of design and construction of the bridges on this rail has accumulated valuable experience for high-speed railway construction on a large scale in the future,and made it a marking,demonstrating,and model project to follow.展开更多
The application-specific multiprocessor system-on-chip(MPSoC) architecture is becoming an attractive solution to deal with increasingly complex embedded applications,which require both high performance and flexible pr...The application-specific multiprocessor system-on-chip(MPSoC) architecture is becoming an attractive solution to deal with increasingly complex embedded applications,which require both high performance and flexible programmability. As an effective method for MPSoC development,we present a gradual refinement flow starting from a high-level Simulink model to a synthesizable and executable hardware and software specification. The proposed methodology consists of five different abstract levels:Simulink combined algorithm and architecture model(CAAM),virtual architecture(VA),transactional accurate architecture(TA),virtual prototype(VP) and field-programmable gate array(FPGA) emulation. Experimental results of Motion-JPEG and H.264 show that the proposed gradual refinement flow can generate various MPSoC architectures from an original Simulink model,allowing processor,communication and tasks design space exploration.展开更多
Phytoplankton functional groups have gained increasing attention in recent years.To understand the composition of phytoplankton functional groups in Poyang Lake and their drivers,field investigations were conducted ov...Phytoplankton functional groups have gained increasing attention in recent years.To understand the composition of phytoplankton functional groups in Poyang Lake and their drivers,field investigations were conducted over three years:2013,2014,and 2016.Phytoplankton were dominated by diatoms,contributing from 20.19%to 57.57%of the total biomass,followed by cyanobacteria,9.81%-39.98%.Microcystis sp.and Anabaena sp.were the dominant species among cyanobacteria.Twenty-six functional groups were identified among 72 genera or species,and fiver groups(P,B,MP,H1,and G)were categorized dominant.All of dominant groups except H1 were tolerate highly fluctuating mixing intensities and showed a typical monthly succession variation.Water temperature,water level,and nutrients are key drivers for the variation of phytoplankton communities at taxonomic and functional levels.Both of redundancy and variation partitioning analyses showed that environmental variables might explain functional groups better than taxonomic communities,implying that the functional groups were more advantageous in showing the effects of environmental conditions than taxonomic compositions.Hydrological conditions have a crucial influence on phytoplankton assemblage dynamics in highly variable water regime lakes,but not in the largest ones.The functional groups method is suitable for identifying the spatial and seasonal characteristics of aquatic environments that significantly affected by water regimes.展开更多
Robots have important applications in industrial production, transportation, environmental monitoring and other fields, and multi-robot collaboration is a research hotspot in recent years. Multi-robot autonomous colla...Robots have important applications in industrial production, transportation, environmental monitoring and other fields, and multi-robot collaboration is a research hotspot in recent years. Multi-robot autonomous collaborative tasks are limited by communication, and there are problems such as poor resource allocation balance, slow response of the system to dynamic changes in the environment, and limited collaborative operation capabilities. The combination of 5G and beyond communication and edge computing can effectively reduce the transmission delay of task offloading and improve task processing efficiency. First, this paper designs a robot autonomous collaborative computing architecture based on 5G and beyond and mobile edge computing(MEC).Then, the robot cooperative computing optimization problem is studied according to the task characteristics of the robot swarm. Then, a reinforcement learning task offloading scheme based on Qlearning is further proposed, so that the overall energy consumption and delay of the robot cluster can be minimized. Finally, simulation experiments demonstrate that the method has significant performance advantages.展开更多
There are more and more research on active control in the application of civil structure.However,some problems such as the drive levers design,optimization and control law problems restricted its application developme...There are more and more research on active control in the application of civil structure.However,some problems such as the drive levers design,optimization and control law problems restricted its application development.In this work,we presented a kind of piezoelectric drive lever to convert pulling force to pressure without flexural moments based on characteristics of the piezoelectric pile,using the genetic algorithm to optimize the layout of the driving lever,which greatly improved the efficiency.Then an active control experiment on a three-layer intelligence space structure was carried out.The experimental data show that the intelligent structures can produce through active control greatly inhibitive effects on the correspondingly controlled modal displacement and acceleration.Spectral analysis shows that the corresponding modal damping coefficient can be improved to different degrees.展开更多
基金National Natural Science Foundation of China under Grant Nos.11372061 and 91315301
文摘Recently, the structural fuse has become an important issue in the field of earthquake engineering. Due to the trilinearity of the pushover curve of buildings with metallic structural fuses, the mechanism of the structural fuse is investigated through the ductility equation of a single-degree-of-freedom system, and the corresponding damage-reduction spectrum is proposed to design and retrofit buildings. Furthermore, the controlling parameters, the stiffness ratio between the main frame and structural fuse and the ductility factor of the main frame, are parametrically studied, and it is shown that the structural fuse concept can be achieved by specific combinations of the controlling parameters based on the proposed damage-reduction spectrum. Finally, a design example and a retrofit example, variations of real engineering projects after the 2008 Wenchuan earthquake, are provided to demonstrate the effectiveness of the proposed design procedures using buckling restrained braces as the structural fuses.
文摘Beijing-Tianjin intercity railway is the first newly-built passenger dedicated line with operating speed of 350 km/h in our country. During design,new ideas of bridge construction were carried out to ensure the requirements of safety,comfort and stability of the train under high-speed condition. At the same time,concepts of environmental adaptability,service to transportation and comprehensive benefits were observed. On the whole line,long-bridge schemes were adopted and the most advanced technologies of unballasted track were utilized on bridges,the length of which accounts for 87.7 % of the total line. The success of design and construction of the bridges on this rail has accumulated valuable experience for high-speed railway construction on a large scale in the future,and made it a marking,demonstrating,and model project to follow.
文摘The application-specific multiprocessor system-on-chip(MPSoC) architecture is becoming an attractive solution to deal with increasingly complex embedded applications,which require both high performance and flexible programmability. As an effective method for MPSoC development,we present a gradual refinement flow starting from a high-level Simulink model to a synthesizable and executable hardware and software specification. The proposed methodology consists of five different abstract levels:Simulink combined algorithm and architecture model(CAAM),virtual architecture(VA),transactional accurate architecture(TA),virtual prototype(VP) and field-programmable gate array(FPGA) emulation. Experimental results of Motion-JPEG and H.264 show that the proposed gradual refinement flow can generate various MPSoC architectures from an original Simulink model,allowing processor,communication and tasks design space exploration.
基金Supported by the Science and Technology Project of Jiangxi Provincial Department of Education(Nos.GJJ211938,GJJ211933)the National Natural Science Foundation of China(No.52260026)+2 种基金the Science and Technology Research and Development Project of China Railway Group Limited(No.2021-Major-08)the Major Science and Technology Program of Jiangxi Provincial Department of Water Resources(No.202224ZDKT22)the Young Talents Training Project of Jiangxi Province(No.20204BCJL23040)。
文摘Phytoplankton functional groups have gained increasing attention in recent years.To understand the composition of phytoplankton functional groups in Poyang Lake and their drivers,field investigations were conducted over three years:2013,2014,and 2016.Phytoplankton were dominated by diatoms,contributing from 20.19%to 57.57%of the total biomass,followed by cyanobacteria,9.81%-39.98%.Microcystis sp.and Anabaena sp.were the dominant species among cyanobacteria.Twenty-six functional groups were identified among 72 genera or species,and fiver groups(P,B,MP,H1,and G)were categorized dominant.All of dominant groups except H1 were tolerate highly fluctuating mixing intensities and showed a typical monthly succession variation.Water temperature,water level,and nutrients are key drivers for the variation of phytoplankton communities at taxonomic and functional levels.Both of redundancy and variation partitioning analyses showed that environmental variables might explain functional groups better than taxonomic communities,implying that the functional groups were more advantageous in showing the effects of environmental conditions than taxonomic compositions.Hydrological conditions have a crucial influence on phytoplankton assemblage dynamics in highly variable water regime lakes,but not in the largest ones.The functional groups method is suitable for identifying the spatial and seasonal characteristics of aquatic environments that significantly affected by water regimes.
文摘Robots have important applications in industrial production, transportation, environmental monitoring and other fields, and multi-robot collaboration is a research hotspot in recent years. Multi-robot autonomous collaborative tasks are limited by communication, and there are problems such as poor resource allocation balance, slow response of the system to dynamic changes in the environment, and limited collaborative operation capabilities. The combination of 5G and beyond communication and edge computing can effectively reduce the transmission delay of task offloading and improve task processing efficiency. First, this paper designs a robot autonomous collaborative computing architecture based on 5G and beyond and mobile edge computing(MEC).Then, the robot cooperative computing optimization problem is studied according to the task characteristics of the robot swarm. Then, a reinforcement learning task offloading scheme based on Qlearning is further proposed, so that the overall energy consumption and delay of the robot cluster can be minimized. Finally, simulation experiments demonstrate that the method has significant performance advantages.
基金Funded by General Planned Research Program of the National Natural Science Foundation of China (No. 90715003)Key Science and Technology Program of the Ministry of Education of China (No. 209124)+6 种基金Ph.D. Programs Foundation of the Ministry of Education of China (No. 200807030002)Shaanxi Key Industry Research Project (No. 2008K07-31)Shaanxi Natural Science Foundation Research Fund (No. 2007E205)Shaanxi Key Laboratory Project (No. 08JZ35)National Key Laboratory Open Project (No. 08KF02)Shaanxi Provincial Key Laboratory Research Project (No. 09JS022)Key Laboratory Project of Shaanxi Department of Education (No. 09JS023),Key Laboratory Project of Shaanxi Department of Education by Visiting Scholars (No. 09JS024)
文摘There are more and more research on active control in the application of civil structure.However,some problems such as the drive levers design,optimization and control law problems restricted its application development.In this work,we presented a kind of piezoelectric drive lever to convert pulling force to pressure without flexural moments based on characteristics of the piezoelectric pile,using the genetic algorithm to optimize the layout of the driving lever,which greatly improved the efficiency.Then an active control experiment on a three-layer intelligence space structure was carried out.The experimental data show that the intelligent structures can produce through active control greatly inhibitive effects on the correspondingly controlled modal displacement and acceleration.Spectral analysis shows that the corresponding modal damping coefficient can be improved to different degrees.