Walking is the basic locomotion pattern for bipedal robots.The walking pattern is widely generated using the linear inverted pendulum model.The linear inverted pendulum motion of each support period can be designed as...Walking is the basic locomotion pattern for bipedal robots.The walking pattern is widely generated using the linear inverted pendulum model.The linear inverted pendulum motion of each support period can be designed as a walk primitive to be connected to form a walking trajectory.A novel method of integrating double support phase into the walk primitive was proposed in this article.The method describes the generation of walking patterns using walk primitives with double support,specifically for lateral plane including walking in place,walking for lateral,and walking initiation,and for sagittal plane including fixed step length walking,variable step length walking,and walking initiation.Compared to walk primitives without double support phase,those with double support phase reduce the maximum speed required by the robot and eliminate the need to adjust foothold for achieving continuous speed.The performance of the proposed method is validated by simulations and experiments on Neubot,a position-controlled biped robot.展开更多
This paper discusses the adaptive strategies and practical effectiveness of SMEs in Shandong Province during the process of digital transformation.It analyzes the key positive factors within the internal and external ...This paper discusses the adaptive strategies and practical effectiveness of SMEs in Shandong Province during the process of digital transformation.It analyzes the key positive factors within the internal and external environments of enterprises,as well as the mutual support between traditional and emerging digital industries,by constructing a comprehensive influencing model of the“double support”framework.The study adopts a combination of quantitative and qualitative methods,collecting data through questionnaires,the Delphi method,and case studies,and applying the DEMATEL model to reveal the interactions and interdependencies between internal and external factors.The findings show that internal management optimization,technological innovation,market positioning,and supply chain management are the core internal drivers of digital transformation,while government policy,market demand,and industry chain synergy are the key external drivers.Through the application of the DEMATEL model,this study further clarifies the interactions and impacts between these factors,providing both a theoretical foundation and practical guidance for enterprises to formulate targeted digital transformation strategies.In addition,the study proposes differentiated transformation paths according to the different development stages of enterprises,in order to help them achieve smooth and effective digital transformation and enhance their competitiveness and market position.The results not only enrich the micro-level theory of digital transformation in SMEs but also provide concrete guidance for practice,offering important theoretical and practical significance.展开更多
Preparing materials for simultaneous remediation of anionic and cationic heavy metals contamination has always been the focus of research. Herein a biochar supported FeMnMg layered double hydroxide(LDH) composites(LB)...Preparing materials for simultaneous remediation of anionic and cationic heavy metals contamination has always been the focus of research. Herein a biochar supported FeMnMg layered double hydroxide(LDH) composites(LB) for simultaneous remediation of copper and arsenic contamination in water and soil has been assembled by a facile co-precipitation approach. Both adsorption isotherm and kinetics studies of heavy metals removal by LB were applied to look into the adsorption performance of adsorbents in water. Moreover, the adsorption mechanisms of Cu and As by LB were investigated, showing that Cu in aqueous solution was removed by the isomorphic substitution, precipitation and electrostatic adsorption while As was removed by complexation. In addition, the availability of Cu and As in the soil incubation experiments was reduced by 35.54%–63.00% and 8.39%–29.04%, respectively by using LB. Meanwhile, the addition of LB increased the activities of urease and sucrase by 93.78%–374.35% and 84.35%–520.04%, respectively, of which 1% of the dosage was the best. A phenomenon was found that the richness and structure of microbial community became vigorous within 1% dosage of LB, which indirectly enhanced the passivation and stabilization of heavy metals. These results indicated that the soil environment was significantly improved by LB. This research demonstrates that LB would be an imaginably forceful material for the remediation of anionic and cationic heavy metals in contaminated water and soil.展开更多
At present, subway stations are often built in densely populated urban centers, the space of construction sites is very limited, and the surrounding buildings, pipelines and other environmental conditions are complex....At present, subway stations are often built in densely populated urban centers, the space of construction sites is very limited, and the surrounding buildings, pipelines and other environmental conditions are complex. When the foundation pit of the main retaining structure of subway station is excavated, the supporting system of double row reinforced concrete pile is adopted, and the crown beam is connected with the top of two rows of concrete pile, which can play the whole role of supporting system. The support system does not need to set up internal support, and has better lateral stiffness, which can effectively control the deformation of foundation pit, and the support depth is deeper than that of single row pile cantilever support structure and convenient earthwork excavation, shorten the construction period, save investment. This paper mainly introduces the stress characteristics, construction process and quality control points of double row supporting piles in the main body of subway station.展开更多
基金supported in part by the National Key R&D Program under Grant 2018YFB1304504.
文摘Walking is the basic locomotion pattern for bipedal robots.The walking pattern is widely generated using the linear inverted pendulum model.The linear inverted pendulum motion of each support period can be designed as a walk primitive to be connected to form a walking trajectory.A novel method of integrating double support phase into the walk primitive was proposed in this article.The method describes the generation of walking patterns using walk primitives with double support,specifically for lateral plane including walking in place,walking for lateral,and walking initiation,and for sagittal plane including fixed step length walking,variable step length walking,and walking initiation.Compared to walk primitives without double support phase,those with double support phase reduce the maximum speed required by the robot and eliminate the need to adjust foothold for achieving continuous speed.The performance of the proposed method is validated by simulations and experiments on Neubot,a position-controlled biped robot.
文摘This paper discusses the adaptive strategies and practical effectiveness of SMEs in Shandong Province during the process of digital transformation.It analyzes the key positive factors within the internal and external environments of enterprises,as well as the mutual support between traditional and emerging digital industries,by constructing a comprehensive influencing model of the“double support”framework.The study adopts a combination of quantitative and qualitative methods,collecting data through questionnaires,the Delphi method,and case studies,and applying the DEMATEL model to reveal the interactions and interdependencies between internal and external factors.The findings show that internal management optimization,technological innovation,market positioning,and supply chain management are the core internal drivers of digital transformation,while government policy,market demand,and industry chain synergy are the key external drivers.Through the application of the DEMATEL model,this study further clarifies the interactions and impacts between these factors,providing both a theoretical foundation and practical guidance for enterprises to formulate targeted digital transformation strategies.In addition,the study proposes differentiated transformation paths according to the different development stages of enterprises,in order to help them achieve smooth and effective digital transformation and enhance their competitiveness and market position.The results not only enrich the micro-level theory of digital transformation in SMEs but also provide concrete guidance for practice,offering important theoretical and practical significance.
基金supported by the National Key Research and Development Program of China (No. 2018YFC1802800)the Local Innovation and Entrepreneurship Team Project of Guangdong Special Support Program (No. 2019BT02L218)the National Natural Science Foundation of China (Nos. 41673091, U1501234)。
文摘Preparing materials for simultaneous remediation of anionic and cationic heavy metals contamination has always been the focus of research. Herein a biochar supported FeMnMg layered double hydroxide(LDH) composites(LB) for simultaneous remediation of copper and arsenic contamination in water and soil has been assembled by a facile co-precipitation approach. Both adsorption isotherm and kinetics studies of heavy metals removal by LB were applied to look into the adsorption performance of adsorbents in water. Moreover, the adsorption mechanisms of Cu and As by LB were investigated, showing that Cu in aqueous solution was removed by the isomorphic substitution, precipitation and electrostatic adsorption while As was removed by complexation. In addition, the availability of Cu and As in the soil incubation experiments was reduced by 35.54%–63.00% and 8.39%–29.04%, respectively by using LB. Meanwhile, the addition of LB increased the activities of urease and sucrase by 93.78%–374.35% and 84.35%–520.04%, respectively, of which 1% of the dosage was the best. A phenomenon was found that the richness and structure of microbial community became vigorous within 1% dosage of LB, which indirectly enhanced the passivation and stabilization of heavy metals. These results indicated that the soil environment was significantly improved by LB. This research demonstrates that LB would be an imaginably forceful material for the remediation of anionic and cationic heavy metals in contaminated water and soil.
文摘At present, subway stations are often built in densely populated urban centers, the space of construction sites is very limited, and the surrounding buildings, pipelines and other environmental conditions are complex. When the foundation pit of the main retaining structure of subway station is excavated, the supporting system of double row reinforced concrete pile is adopted, and the crown beam is connected with the top of two rows of concrete pile, which can play the whole role of supporting system. The support system does not need to set up internal support, and has better lateral stiffness, which can effectively control the deformation of foundation pit, and the support depth is deeper than that of single row pile cantilever support structure and convenient earthwork excavation, shorten the construction period, save investment. This paper mainly introduces the stress characteristics, construction process and quality control points of double row supporting piles in the main body of subway station.
