This paper introduces the architecture of wireless sensor networks, presents a cross-layer network management and control mechanism. The key technologies, such as Medium Access Control (MAC) and wireless routing proto...This paper introduces the architecture of wireless sensor networks, presents a cross-layer network management and control mechanism. The key technologies, such as Medium Access Control (MAC) and wireless routing protocols are discussed and compared. A proposal of applying the simple IEEE 802 MAC protocol into the wireless sensor network is introduced. In addition, in order to improve the system capacity, a multi-channel strategy for the sensor nodes is presented for decreasing the blocking probability and suppressing the accessing time delay. It is concluded that there are still a number of problems to be solved, including decreasing power consumption, improving capacity and avoiding access collision, to promote the successful commercial application of wireless sensor network.展开更多
Based on basic situational research and analysis carried out on 638 college students using network, we found that as many as 20 percent of the students are not only largely dependent on internet, but also addicted to ...Based on basic situational research and analysis carried out on 638 college students using network, we found that as many as 20 percent of the students are not only largely dependent on internet, but also addicted to it. Further biography characteristics analyses for different individuals on the four dimensions of the network forced addiction, tolerance, and time management and interpersonal relationship and health, show that there are significant differences in grades, gender with different education levels of their parents. Further researches on discrepancy that addicted groups have in network entertainment addiction, network information, cyber porn, network relations and network transactions addictions also illustrate that significant discrepancies exist in gender, net age, different discipline and other factors. Finally we put forward some correlative measures to solve the problems of college students network psychology from individuals, schools, and society levels.展开更多
Hypoxia is a common pathological process in various clinical diseases and is characterized by abnormal changes in metabolism, function, and morphological structure of tissues resulting from insufficient oxygen supply ...Hypoxia is a common pathological process in various clinical diseases and is characterized by abnormal changes in metabolism, function, and morphological structure of tissues resulting from insufficient oxygen supply or oxygen barriers in tissues. In particular, hypoxia in vital organs such as the brain and heart is an important cause of death;. The prevention of tissue hypoxia and the展开更多
文摘This paper introduces the architecture of wireless sensor networks, presents a cross-layer network management and control mechanism. The key technologies, such as Medium Access Control (MAC) and wireless routing protocols are discussed and compared. A proposal of applying the simple IEEE 802 MAC protocol into the wireless sensor network is introduced. In addition, in order to improve the system capacity, a multi-channel strategy for the sensor nodes is presented for decreasing the blocking probability and suppressing the accessing time delay. It is concluded that there are still a number of problems to be solved, including decreasing power consumption, improving capacity and avoiding access collision, to promote the successful commercial application of wireless sensor network.
基金Financial support from the Foundation of Philosophy and Social Sciences of University of Jiangsu Provincial Department of Education (No. 2011SJB880048)the Students Practical and Innovative Training Program of Jiangsu Provincial University
文摘Based on basic situational research and analysis carried out on 638 college students using network, we found that as many as 20 percent of the students are not only largely dependent on internet, but also addicted to it. Further biography characteristics analyses for different individuals on the four dimensions of the network forced addiction, tolerance, and time management and interpersonal relationship and health, show that there are significant differences in grades, gender with different education levels of their parents. Further researches on discrepancy that addicted groups have in network entertainment addiction, network information, cyber porn, network relations and network transactions addictions also illustrate that significant discrepancies exist in gender, net age, different discipline and other factors. Finally we put forward some correlative measures to solve the problems of college students network psychology from individuals, schools, and society levels.
基金financially supported by 1226 major project [Grant no.AWS16J018]
文摘Hypoxia is a common pathological process in various clinical diseases and is characterized by abnormal changes in metabolism, function, and morphological structure of tissues resulting from insufficient oxygen supply or oxygen barriers in tissues. In particular, hypoxia in vital organs such as the brain and heart is an important cause of death;. The prevention of tissue hypoxia and the
