The water potential (Ψ) daily courses of 9 woody species from Cerrado vegetation in different weather conditions during wet season were observed and analyzed. The adjusting strategies of 9 species could be divided in...The water potential (Ψ) daily courses of 9 woody species from Cerrado vegetation in different weather conditions during wet season were observed and analyzed. The adjusting strategies of 9 species could be divided into 3 groups according to Cluster Analysis and based on the data observed on the January 18, March 20 and April 6. The Ψ values of the first group, which included 2 species, were maintained at the higher level consistently. The Ψ values of the second group, which included 5 species, were intermediate level. The Ψ values of the third group, which included 2 species, were kept in the lower level. The Ψ values of all species always kept pace with the weather condition, especially water condition. During the clear day only one Ψ value peak for all species occurred at midday (12∶30–13∶30). When the overcast or raining occurred for a short period, the fluctuation of Ψ values would appear after about 15–30 min responding to the change of weather condition. Even in the same group under the same external circumstance, there was a clear variation of the leaf Ψ values among different species, which showed that the strategy diversity for plant to balance water relation. From January to April, the Ψ values of 9 species reduced in response to the drought condition. The species with the lower values of water saturation deficiency at turgid loss point (W sdtlp) the osmotic potential at saturation (πsat), the osmotic potential at turgid lose point (πtip) or lower predawn water potential (Ψpd) usually had the lower Ψ values at midday. The mechanism of water balance controlled by many systems has been assumed.展开更多
With the growing amounts of multi-micro grids,electric vehicles,smart home,smart cities connected to the Power Distribution Internet of Things(PD-IoT)system,greater computing resource and communication bandwidth are r...With the growing amounts of multi-micro grids,electric vehicles,smart home,smart cities connected to the Power Distribution Internet of Things(PD-IoT)system,greater computing resource and communication bandwidth are required for power distribution.It probably leads to extreme service delay and data congestion when a large number of data and business occur in emergence.This paper presents a service scheduling method based on edge computing to balance the business load of PD-IoT.The architecture,components and functional requirements of the PD-IoT with edge computing platform are proposed.Then,the structure of the service scheduling system is presented.Further,a novel load balancing strategy and ant colony algorithm are investigated in the service scheduling method.The validity of the method is evaluated by simulation tests.Results indicate that the mean load balancing ratio is reduced by 99.16%and the optimized offloading links can be acquired within 1.8 iterations.Computing load of the nodes in edge computing platform can be effectively balanced through the service scheduling.展开更多
For quadruped robots with springy legs,a successful jump usually requires both suitable elastic parts and well-designed control algorithms.However,these two problems are mutually restricted and hard to solve at the sa...For quadruped robots with springy legs,a successful jump usually requires both suitable elastic parts and well-designed control algorithms.However,these two problems are mutually restricted and hard to solve at the same time.In this study,we attempt to solve the problem of controller design with the help of a robot without any elastic mounted parts,in which the untethered robot is made to jump on a trampoline.The differences between jumping on hard surfaces with springy legs and jumping on springy surfaces with rigid legs are briefly discussed.An intuitive control law is proposed to balance foot contact forces;in this manner,excessive pitch oscillation during hopping or bounding can be avoided.Hopping height is controlled by tuning the time delay of the leg stretch.Together with other motion generators based on kinematic law,the robot can perform translational and rotational movements while hopping or bounding on the trampoline.Experiments are conducted to validate the effectiveness of the proposed control framework.展开更多
After the end of the Cold War,the US pushed its hegemonic strategy fully in the Middle East depending on its position as the only super power in the world and tried to establish its hegemony in the Middle East with mi...After the end of the Cold War,the US pushed its hegemonic strategy fully in the Middle East depending on its position as the only super power in the world and tried to establish its hegemony in the Middle East with military interference and political reconstruction.However,the Iraq war that the US launched in 2003 has not only consumed much of its own strength but also caused many conditions that the US cannot deal with,such as the increase of the Iranian theocratic power,the expanding of terrorism,and the spread of Islamic people’s uprisings.Faced with the combination and the development of anti-US forces,the US has to adjust its strategy and replace military hegemony with an offshore balancing strategy.The offshore balancing strategy stresses that the US should transfer the responsibility of maintaining the regional security to the allies in this region and encourages them to form a balance to contain the hostile Islamic forces.At the same time,the US should withdraw its military force from the Middle East region.It will be helpful to avoid the hostile Islamic forces to prompt the anti-US sentiment and to maintain hegemony for the US in the region with a more cover way.展开更多
文摘The water potential (Ψ) daily courses of 9 woody species from Cerrado vegetation in different weather conditions during wet season were observed and analyzed. The adjusting strategies of 9 species could be divided into 3 groups according to Cluster Analysis and based on the data observed on the January 18, March 20 and April 6. The Ψ values of the first group, which included 2 species, were maintained at the higher level consistently. The Ψ values of the second group, which included 5 species, were intermediate level. The Ψ values of the third group, which included 2 species, were kept in the lower level. The Ψ values of all species always kept pace with the weather condition, especially water condition. During the clear day only one Ψ value peak for all species occurred at midday (12∶30–13∶30). When the overcast or raining occurred for a short period, the fluctuation of Ψ values would appear after about 15–30 min responding to the change of weather condition. Even in the same group under the same external circumstance, there was a clear variation of the leaf Ψ values among different species, which showed that the strategy diversity for plant to balance water relation. From January to April, the Ψ values of 9 species reduced in response to the drought condition. The species with the lower values of water saturation deficiency at turgid loss point (W sdtlp) the osmotic potential at saturation (πsat), the osmotic potential at turgid lose point (πtip) or lower predawn water potential (Ψpd) usually had the lower Ψ values at midday. The mechanism of water balance controlled by many systems has been assumed.
基金This work was supported by the National Natural Science Foundation of China(Grant:61702048).
文摘With the growing amounts of multi-micro grids,electric vehicles,smart home,smart cities connected to the Power Distribution Internet of Things(PD-IoT)system,greater computing resource and communication bandwidth are required for power distribution.It probably leads to extreme service delay and data congestion when a large number of data and business occur in emergence.This paper presents a service scheduling method based on edge computing to balance the business load of PD-IoT.The architecture,components and functional requirements of the PD-IoT with edge computing platform are proposed.Then,the structure of the service scheduling system is presented.Further,a novel load balancing strategy and ant colony algorithm are investigated in the service scheduling method.The validity of the method is evaluated by simulation tests.Results indicate that the mean load balancing ratio is reduced by 99.16%and the optimized offloading links can be acquired within 1.8 iterations.Computing load of the nodes in edge computing platform can be effectively balanced through the service scheduling.
基金Financial support was provided by the Zhejiang Provincial Natural Science Foundation(Grant No.Y18F030012)the Science and Technology Project of Zhejiang Province(Grant No.2019C01043)+1 种基金the National Natural Science Foundation of China(Grant No.61836015)the State Key Laboratory of Industrial Control Technology(ICT1807)。
文摘For quadruped robots with springy legs,a successful jump usually requires both suitable elastic parts and well-designed control algorithms.However,these two problems are mutually restricted and hard to solve at the same time.In this study,we attempt to solve the problem of controller design with the help of a robot without any elastic mounted parts,in which the untethered robot is made to jump on a trampoline.The differences between jumping on hard surfaces with springy legs and jumping on springy surfaces with rigid legs are briefly discussed.An intuitive control law is proposed to balance foot contact forces;in this manner,excessive pitch oscillation during hopping or bounding can be avoided.Hopping height is controlled by tuning the time delay of the leg stretch.Together with other motion generators based on kinematic law,the robot can perform translational and rotational movements while hopping or bounding on the trampoline.Experiments are conducted to validate the effectiveness of the proposed control framework.
基金This research is the product of Chinese Educational Ministry program“Research on the Kurds Affairs in Middle East”(2009JJD810009)“Islamic Middle East Region and the Transition of International System”(08JZD0039)supported by Shanghai International Studies University“211”program.
文摘After the end of the Cold War,the US pushed its hegemonic strategy fully in the Middle East depending on its position as the only super power in the world and tried to establish its hegemony in the Middle East with military interference and political reconstruction.However,the Iraq war that the US launched in 2003 has not only consumed much of its own strength but also caused many conditions that the US cannot deal with,such as the increase of the Iranian theocratic power,the expanding of terrorism,and the spread of Islamic people’s uprisings.Faced with the combination and the development of anti-US forces,the US has to adjust its strategy and replace military hegemony with an offshore balancing strategy.The offshore balancing strategy stresses that the US should transfer the responsibility of maintaining the regional security to the allies in this region and encourages them to form a balance to contain the hostile Islamic forces.At the same time,the US should withdraw its military force from the Middle East region.It will be helpful to avoid the hostile Islamic forces to prompt the anti-US sentiment and to maintain hegemony for the US in the region with a more cover way.