According to the property rights model of cognitive radio,primary users who own the spectral resource have the right to lease or trade part of it to secondary users in exchange for appropriate profit.In this paper,an ...According to the property rights model of cognitive radio,primary users who own the spectral resource have the right to lease or trade part of it to secondary users in exchange for appropriate profit.In this paper,an implementation of this framework is investigated,where a primary link can lease the owned spectrum to secondary nodes in exchange for cooperation （relaying）.A novel pricing model is proposed that enables the trading between spectrum and cooperation.Based on the demand of secondary nodes,the primary link attempts to maximize its quality of service （QoS） by setting the price of spectrum.Taking the price asked by primary link,the secondary nodes aim to obtain most profits by deciding the amount of spectrum to buy and then pay for it by cooperative transmission.The investigated model is conveniently cast in the framework of seller/buyer （Stackelberg） games.Analysis and numerical results show that our pricing model is effective and practical for spectrum leasing based on trading spectral resource for cooperation.展开更多
Secondary electron emission （SEE） of metal and dielectric materials plays a key role in multipactor discharge, which is a bottle neck problem for high-power satelliate components. Measurements of both the secondary ...Secondary electron emission （SEE） of metal and dielectric materials plays a key role in multipactor discharge, which is a bottle neck problem for high-power satelliate components. Measurements of both the secondary electron yield （SEY） and the secondary electron energy spectrum （SES） are performed on metal samples for an accurate description of the real SEE phenomenon. In order to simplify the fitting process and improve the simulation efficiency, an improved model is proposed for the description of secondary electrons （SE） emitted from the material surface, including true, elastic, and inelastic SE. Embedding the novel SES model into the electromagnetic particle-in-cell method, the electronic resonant multipactor in microwave components is simulated successfully and hence the discharge threshold is predicted. Simulation results of the SES variation in the improved model demonstrate that the multipactor threshold is strongly dependent on SES. In addition, the mutipactor simulation results agree quite well with the experiment for the practical microwave component, while the numerical model of SEY and SES fits well with the sample data taken from the microwave component.展开更多
The secondary electrons spectrum in XPS can be used to determine the work function of polyaniline (PANI). It is shown that the work function of PANI depends on the protonation state and the polymerization method used.
基金supported by the National Basic Research Program of China (2009CB320401)the National Natural Science Foundation of China (60772108)the Fundamental Research Funds for the Central Universities (BUPT2009RC0111)
文摘According to the property rights model of cognitive radio,primary users who own the spectral resource have the right to lease or trade part of it to secondary users in exchange for appropriate profit.In this paper,an implementation of this framework is investigated,where a primary link can lease the owned spectrum to secondary nodes in exchange for cooperation （relaying）.A novel pricing model is proposed that enables the trading between spectrum and cooperation.Based on the demand of secondary nodes,the primary link attempts to maximize its quality of service （QoS） by setting the price of spectrum.Taking the price asked by primary link,the secondary nodes aim to obtain most profits by deciding the amount of spectrum to buy and then pay for it by cooperative transmission.The investigated model is conveniently cast in the framework of seller/buyer （Stackelberg） games.Analysis and numerical results show that our pricing model is effective and practical for spectrum leasing based on trading spectral resource for cooperation.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.U1537211,11705142,and 11675278)the National Key Laboratory Foundation,China(Grant No.9140C530101150C53011)
文摘Secondary electron emission （SEE） of metal and dielectric materials plays a key role in multipactor discharge, which is a bottle neck problem for high-power satelliate components. Measurements of both the secondary electron yield （SEY） and the secondary electron energy spectrum （SES） are performed on metal samples for an accurate description of the real SEE phenomenon. In order to simplify the fitting process and improve the simulation efficiency, an improved model is proposed for the description of secondary electrons （SE） emitted from the material surface, including true, elastic, and inelastic SE. Embedding the novel SES model into the electromagnetic particle-in-cell method, the electronic resonant multipactor in microwave components is simulated successfully and hence the discharge threshold is predicted. Simulation results of the SES variation in the improved model demonstrate that the multipactor threshold is strongly dependent on SES. In addition, the mutipactor simulation results agree quite well with the experiment for the practical microwave component, while the numerical model of SEY and SES fits well with the sample data taken from the microwave component.
文摘The secondary electrons spectrum in XPS can be used to determine the work function of polyaniline (PANI). It is shown that the work function of PANI depends on the protonation state and the polymerization method used.
