In this paper,we consider a cognitive radio system with energy harvesting,in which the secondary user operates in a saving-sensing-transmitting(SST) fashion.We investigate the tradeoff between energy harvesting,channe...In this paper,we consider a cognitive radio system with energy harvesting,in which the secondary user operates in a saving-sensing-transmitting(SST) fashion.We investigate the tradeoff between energy harvesting,channel sensing and data transmission and focus on the optimal SST structure to maximize the SU's expected achievable throughput.We consider imperfect knowledge of energy harvesting rate,which cannot be exactly known and only its statistical information is available.By formulating the problem of expected achievable throughput optimization as a mixed-integer non-linear programming one,we derive the optimal saveratio and number of sensed channels with indepth analysis.Simulation results show that the optimal SST structure outperforms random one and performance gain can be enhanced by increasing the SU's energy harvesting rate.展开更多
Data are critically important to good decision-making. In an increasingly complex economy, conventional data collecting schemes are no longer sufficient. To deal with the challenge of maintaining its statistics releva...Data are critically important to good decision-making. In an increasingly complex economy, conventional data collecting schemes are no longer sufficient. To deal with the challenge of maintaining its statistics relevant to the users in an ever-shifting environment, the Banco de Portugal decided to explore the largely unused statistical potential of the available micro-databases and to integrate the existing administrative and survey data, thus enhancing the basic information infrastructure while protecting confidentiality. This presentation will address the benefits and problems to be dealt with when two or more data-sources are to be integrated.展开更多
Data mining involves extracting information from large data sets, discovering the hidden relationships and unknown dependencies, and supporting strategic decision-making tasks. The alignment of data mining and busines...Data mining involves extracting information from large data sets, discovering the hidden relationships and unknown dependencies, and supporting strategic decision-making tasks. The alignment of data mining and business would bring benefits to the organization＇s management. The study investigated the adoption of data mining technologies in managerial accounting system, concentrating on the challenges and opportunities. The research showed that with the technology adoption, managerial functions could be improved and current information system could be upgraded. Since the technical progresses are reshaping the world of business and accountancy, it is significant for accountants and finance professionals to exploit information technologies.展开更多
This paper deals with the function u which satisfies△k_u = 0, where k≥2 is an integer. Such a function u is called a polyharmonic function. The author gives an upper bound of the measure of the nodal set of u, and s...This paper deals with the function u which satisfies△k_u = 0, where k≥2 is an integer. Such a function u is called a polyharmonic function. The author gives an upper bound of the measure of the nodal set of u, and shows some growth property of u.展开更多
基金supported by National Nature Science Foundation of China（NO.61372109）
文摘In this paper,we consider a cognitive radio system with energy harvesting,in which the secondary user operates in a saving-sensing-transmitting(SST) fashion.We investigate the tradeoff between energy harvesting,channel sensing and data transmission and focus on the optimal SST structure to maximize the SU's expected achievable throughput.We consider imperfect knowledge of energy harvesting rate,which cannot be exactly known and only its statistical information is available.By formulating the problem of expected achievable throughput optimization as a mixed-integer non-linear programming one,we derive the optimal saveratio and number of sensed channels with indepth analysis.Simulation results show that the optimal SST structure outperforms random one and performance gain can be enhanced by increasing the SU's energy harvesting rate.
文摘Data are critically important to good decision-making. In an increasingly complex economy, conventional data collecting schemes are no longer sufficient. To deal with the challenge of maintaining its statistics relevant to the users in an ever-shifting environment, the Banco de Portugal decided to explore the largely unused statistical potential of the available micro-databases and to integrate the existing administrative and survey data, thus enhancing the basic information infrastructure while protecting confidentiality. This presentation will address the benefits and problems to be dealt with when two or more data-sources are to be integrated.
文摘Data mining involves extracting information from large data sets, discovering the hidden relationships and unknown dependencies, and supporting strategic decision-making tasks. The alignment of data mining and business would bring benefits to the organization＇s management. The study investigated the adoption of data mining technologies in managerial accounting system, concentrating on the challenges and opportunities. The research showed that with the technology adoption, managerial functions could be improved and current information system could be upgraded. Since the technical progresses are reshaping the world of business and accountancy, it is significant for accountants and finance professionals to exploit information technologies.
基金supported by the National Natural Science Foundation of China(Nos.11401307,11501292)
文摘This paper deals with the function u which satisfies△k_u = 0, where k≥2 is an integer. Such a function u is called a polyharmonic function. The author gives an upper bound of the measure of the nodal set of u, and shows some growth property of u.
