The formation problem of multi-agent systems via coordinated control is investigated,where the multiple agents can achieve the common velocity with leader and avoid collision during the evolution.In the real-world sit...The formation problem of multi-agent systems via coordinated control is investigated,where the multiple agents can achieve the common velocity with leader and avoid collision during the evolution.In the real-world situation,the communication is often disturbed and inaccurate.Hence,the unknown disturbances are considered in the velocity measurements,which is assumed to be bounded and does not need to be modelled.Moreover,a complicated nonlinear interaction among agents is presented in the design of control.Based on the existing work of multi-agent systems,a flocking control protocol is proposed to address the formation problem in the dynamic topology.The stability analysis is given to prove that the velocities of all agents can converge to the velocity of leader and the stable motion with collision avoidance can be achieved eventually.Finally,some simulations are presented to verify the effectiveness of the proposed algorithm.展开更多
TDD(Time Division Duplex) is one of the two duplex modes.TD-SCDMA(Time division Synchronous CDMA) is the first TDD-based cellular mobile system which is commercialized in wide area and large scale and TD-SCDMA is also...TDD(Time Division Duplex) is one of the two duplex modes.TD-SCDMA(Time division Synchronous CDMA) is the first TDD-based cellular mobile system which is commercialized in wide area and large scale and TD-SCDMA is also the first cellular mobile system which adopted smart antenna technology,also called as beamforming.As the long term evolution of TD-SCDMA,TDLTE(A)(Time Division-Lone Term Evolution,and TD-LTE Advanced) introduced OFDM(Orthogonal Frequency Division Multiplexing)and enhanced smart antenna technology together with MIMO(Multiple Input Multiple Output),which are adopted by LTE FDD(Frequency Division Duplex) either.It is indicated that TD-SCDMA and TD-LTE(A)have opened a sustainable utilization era of TDD and smart antenna Technologies in the wireless mobile communication.This paper aims to present a systematic introduction to TDD-based mobile communications from TD-SCDMA to TD-LTE and beyond and its comparisons to FDD,with particular focuses on TDD key technologies,principles of TDD cellular mobile systems,TDD evolution path,and future TDD 5G directions.We hope that this paper will provide a comprehensive overview of TDD technology upgrade and its standard evolution,and serve as a valuable reference for research on 5G mobile communication systems.It is believed that TDD will play more important role in 5G.展开更多
Varroasis is a disease caused by the mite Varroa destructor, which affects honeybees worldwide. It is estimated that it entered Chile in 1992, and it must be controlled through different types of treatments such as th...Varroasis is a disease caused by the mite Varroa destructor, which affects honeybees worldwide. It is estimated that it entered Chile in 1992, and it must be controlled through different types of treatments such as thymol, formic and oxalic acid in different formulations and presentations. This kind of organic products has shown a variable acaricidal capacity, since different factors affect their efficacy such as ambient temperature and humidity, product presentation and location inside the hive, etc.. In Chile, beekeeping takes place in four different climatic zones, in which ambient temperature and humidity as well as the duration of the apicultural season are different. Therefore, the aim of this study was to determine how ambient temperature and humidity influence the efficacy of the organic treatments used in the beekeeping season. Different apiaries were installed in those climatic zones in three seasons between the years 2009 and 2012. All beehives received the same management in each apiary and it was evaluated the same organic treatments in different formulations and presentations. All the beehives were positive to Varroa, which was obtained using samples of adult bees and the soapy water test before and after each treatment. A thermo-hygrometer was installed in each apiary in order to monitor the ambient temperature （T°） and humidity （H°） conditions, which were registered daily for a period of 30 days since the beginning. It was obtained that the treatments＇ efficacy increases as the minimum T° and average T° rose, whereas on the contrary, the efficacy decreases when maximum H° was higher.展开更多
基金the National Key Research and Development Program of China(No.2021ZD0112500)the National Natural Scientific Foundation of China(No.12072128)。
文摘The formation problem of multi-agent systems via coordinated control is investigated,where the multiple agents can achieve the common velocity with leader and avoid collision during the evolution.In the real-world situation,the communication is often disturbed and inaccurate.Hence,the unknown disturbances are considered in the velocity measurements,which is assumed to be bounded and does not need to be modelled.Moreover,a complicated nonlinear interaction among agents is presented in the design of control.Based on the existing work of multi-agent systems,a flocking control protocol is proposed to address the formation problem in the dynamic topology.The stability analysis is given to prove that the velocities of all agents can converge to the velocity of leader and the stable motion with collision avoidance can be achieved eventually.Finally,some simulations are presented to verify the effectiveness of the proposed algorithm.
基金supported in part by the National Natural Science Foundation of China for Distinguished Young Scholar,Grant Number:61425012
文摘TDD(Time Division Duplex) is one of the two duplex modes.TD-SCDMA(Time division Synchronous CDMA) is the first TDD-based cellular mobile system which is commercialized in wide area and large scale and TD-SCDMA is also the first cellular mobile system which adopted smart antenna technology,also called as beamforming.As the long term evolution of TD-SCDMA,TDLTE(A)(Time Division-Lone Term Evolution,and TD-LTE Advanced) introduced OFDM(Orthogonal Frequency Division Multiplexing)and enhanced smart antenna technology together with MIMO(Multiple Input Multiple Output),which are adopted by LTE FDD(Frequency Division Duplex) either.It is indicated that TD-SCDMA and TD-LTE(A)have opened a sustainable utilization era of TDD and smart antenna Technologies in the wireless mobile communication.This paper aims to present a systematic introduction to TDD-based mobile communications from TD-SCDMA to TD-LTE and beyond and its comparisons to FDD,with particular focuses on TDD key technologies,principles of TDD cellular mobile systems,TDD evolution path,and future TDD 5G directions.We hope that this paper will provide a comprehensive overview of TDD technology upgrade and its standard evolution,and serve as a valuable reference for research on 5G mobile communication systems.It is believed that TDD will play more important role in 5G.
文摘Varroasis is a disease caused by the mite Varroa destructor, which affects honeybees worldwide. It is estimated that it entered Chile in 1992, and it must be controlled through different types of treatments such as thymol, formic and oxalic acid in different formulations and presentations. This kind of organic products has shown a variable acaricidal capacity, since different factors affect their efficacy such as ambient temperature and humidity, product presentation and location inside the hive, etc.. In Chile, beekeeping takes place in four different climatic zones, in which ambient temperature and humidity as well as the duration of the apicultural season are different. Therefore, the aim of this study was to determine how ambient temperature and humidity influence the efficacy of the organic treatments used in the beekeeping season. Different apiaries were installed in those climatic zones in three seasons between the years 2009 and 2012. All beehives received the same management in each apiary and it was evaluated the same organic treatments in different formulations and presentations. All the beehives were positive to Varroa, which was obtained using samples of adult bees and the soapy water test before and after each treatment. A thermo-hygrometer was installed in each apiary in order to monitor the ambient temperature （T°） and humidity （H°） conditions, which were registered daily for a period of 30 days since the beginning. It was obtained that the treatments＇ efficacy increases as the minimum T° and average T° rose, whereas on the contrary, the efficacy decreases when maximum H° was higher.
