Most of the multimedia applications require strict Quality-of-Service (QoS) guarantee during the communication between a single source and multiple destinations. The paper mainly presents a QoS Multicast Routing algor...Most of the multimedia applications require strict Quality-of-Service (QoS) guarantee during the communication between a single source and multiple destinations. The paper mainly presents a QoS Multicast Routing algorithms based on Genetic Algorithm (QMRGA). Simulation results demonstrate that the algorithm is capable of discovering a set of QoS-based near optimized, non-dominated multicast routes within a few iterations, even for the networks environment with uncertain parameters.展开更多
Classical network coding permits all internal nodes to encode or decode the incoming messages over proper fields in order to complete a network multicast. Similar quantum encoding scheme cannot be easily followed beca...Classical network coding permits all internal nodes to encode or decode the incoming messages over proper fields in order to complete a network multicast. Similar quantum encoding scheme cannot be easily followed because of various quantum no-go theorems. In this paper, to avoid these theorems in quantum multiple-source networks, we present a photonic strategy by exploring quantum transferring approaches assisted by the weak cross-Kerr nonlinearity. The internal node may nearly deterministically fuse all incoming photons into a single photon with multiple modes. The fused single photon may be transmitted using twophotonic hyperentanglement as a quantum resource. The quantum splitting as the inverse operation of the quantum fusion allows forwarding quantum states under the quantum no-cloning theorem. Furthermore, quantum addressing schemes are presented to complete the quantum transmissions on multiple-source networks going beyond the classical network broadcasts or quantum n-pair transmissions in terms of their reduced forms.展开更多
To estimate the motion parameters of a moving target before its passing by the closest point of approach (CPA) point in a low frequency analyzing and recording (LOFAR) field, an error-free theoretical method based...To estimate the motion parameters of a moving target before its passing by the closest point of approach (CPA) point in a low frequency analyzing and recording (LOFAR) field, an error-free theoretical method based on the joint measurement of target radiated noise's amplitude and frequency was presented. First, the error-free theoretical equations for target characteristic frequency, absolute velocity, the CPA, and amplitude of the radiation noise were derived by three equal interval measured values of the target amplitude and frequency. Then, the method to improve the calculation accuracy was given. Finally, the simulation and experiments were conducted in the air and showed the correctness of this method. By using one single piece of LOFAR, this method can calculate four target parameters and the relative error of each estimated parameter is less than 10%.展开更多
Simultaneous measurements from THEMIS spacecraft, GOES11 and ground stations (Canadian Array for Realtime Investiga tions of Magnetic Activity or CARISMA, and 210 magnetic meridian or MM) on March 18, 2009 allow the...Simultaneous measurements from THEMIS spacecraft, GOES11 and ground stations (Canadian Array for Realtime Investiga tions of Magnetic Activity or CARISMA, and 210 magnetic meridian or MM) on March 18, 2009 allow the study of dynamic processes in the nearEarth magnetotail and corresponding Pi2 pulsations on the ground in great detail. Fast earthward flows along with traveling Alfv6n waves and fast mode waves in the Pi2 band were observed by three Time History of Events and Macroscale Interactions during Substorms (THEM/S) probes (P3, P4 and P5) in the nearEarth plasmasbeet. At the mid to highlatitude nightside, the CARISMA stations located near the foot points of the three probes recorded Pi2s with two periods, about 80 s after the earthward fast flows observed by the P4 probe. The longperiod Pi2 (140-150 s) belongs to the transient response Pi2 (TR Pi2), since the travel time of the Alfv6n waves between the plasma sheet and CARISMA stations is very close to half the period of the longperiod Pi2. The shortperiod Pi2 (60-80 s) has the same period band as the perpendicular velocity of the fast flows, which indicates that it may relate to the inertial current caused by periodic braking of the earthward fast flows. The 210 MM stations located at the lowlatitude duskside also observed Pi2s with the same start time, waveform and frequency, about 120 s after the earthward fast flows. Strong poloidal oscillations are shown by GOES11 (23 MLT) and the compressional component (Bb) is highly correlated with H components of the 210 MM stations, whereas the other two components (Br and Be) are not. These results confirm that the lowlatitude Pi2s are generated by cavity mode resonance, which is driven by an impulsive broadband source in the nearEarth magnetotail.展开更多
基金Supported by the National Natural Science Foundation of China (No.90304018)Natural Science Foundation of Hubei Province (No.2004ABA014)Teaching Research Project of Higher Educational Institutions of Hubei Province (No.20040231).
文摘Most of the multimedia applications require strict Quality-of-Service (QoS) guarantee during the communication between a single source and multiple destinations. The paper mainly presents a QoS Multicast Routing algorithms based on Genetic Algorithm (QMRGA). Simulation results demonstrate that the algorithm is capable of discovering a set of QoS-based near optimized, non-dominated multicast routes within a few iterations, even for the networks environment with uncertain parameters.
基金supported by the National Natural Science Foundation of China (Grant Nos. 61772437, 61702427, and 61671087)the Natural Science Foundation of Shandong Province (Grant No. ZR2015FL024)+2 种基金Sichuan Youth Science and Technique Foundation (Grant No. 2017JQ0048)Fundamental Research Funds for the Central Universities (Grant No. 2682014CX095)Chuying Fellowship
文摘Classical network coding permits all internal nodes to encode or decode the incoming messages over proper fields in order to complete a network multicast. Similar quantum encoding scheme cannot be easily followed because of various quantum no-go theorems. In this paper, to avoid these theorems in quantum multiple-source networks, we present a photonic strategy by exploring quantum transferring approaches assisted by the weak cross-Kerr nonlinearity. The internal node may nearly deterministically fuse all incoming photons into a single photon with multiple modes. The fused single photon may be transmitted using twophotonic hyperentanglement as a quantum resource. The quantum splitting as the inverse operation of the quantum fusion allows forwarding quantum states under the quantum no-cloning theorem. Furthermore, quantum addressing schemes are presented to complete the quantum transmissions on multiple-source networks going beyond the classical network broadcasts or quantum n-pair transmissions in terms of their reduced forms.
基金Project supported by the National Natural Science Foundation of China (No. 51209173)
文摘To estimate the motion parameters of a moving target before its passing by the closest point of approach (CPA) point in a low frequency analyzing and recording (LOFAR) field, an error-free theoretical method based on the joint measurement of target radiated noise's amplitude and frequency was presented. First, the error-free theoretical equations for target characteristic frequency, absolute velocity, the CPA, and amplitude of the radiation noise were derived by three equal interval measured values of the target amplitude and frequency. Then, the method to improve the calculation accuracy was given. Finally, the simulation and experiments were conducted in the air and showed the correctness of this method. By using one single piece of LOFAR, this method can calculate four target parameters and the relative error of each estimated parameter is less than 10%.
基金supported by the National Key Basic Research Program of China (Grant No.2012CB825604)the National Natural Science Foundation of China (Grant Nos.41104093 & 41204122).
文摘Simultaneous measurements from THEMIS spacecraft, GOES11 and ground stations (Canadian Array for Realtime Investiga tions of Magnetic Activity or CARISMA, and 210 magnetic meridian or MM) on March 18, 2009 allow the study of dynamic processes in the nearEarth magnetotail and corresponding Pi2 pulsations on the ground in great detail. Fast earthward flows along with traveling Alfv6n waves and fast mode waves in the Pi2 band were observed by three Time History of Events and Macroscale Interactions during Substorms (THEM/S) probes (P3, P4 and P5) in the nearEarth plasmasbeet. At the mid to highlatitude nightside, the CARISMA stations located near the foot points of the three probes recorded Pi2s with two periods, about 80 s after the earthward fast flows observed by the P4 probe. The longperiod Pi2 (140-150 s) belongs to the transient response Pi2 (TR Pi2), since the travel time of the Alfv6n waves between the plasma sheet and CARISMA stations is very close to half the period of the longperiod Pi2. The shortperiod Pi2 (60-80 s) has the same period band as the perpendicular velocity of the fast flows, which indicates that it may relate to the inertial current caused by periodic braking of the earthward fast flows. The 210 MM stations located at the lowlatitude duskside also observed Pi2s with the same start time, waveform and frequency, about 120 s after the earthward fast flows. Strong poloidal oscillations are shown by GOES11 (23 MLT) and the compressional component (Bb) is highly correlated with H components of the 210 MM stations, whereas the other two components (Br and Be) are not. These results confirm that the lowlatitude Pi2s are generated by cavity mode resonance, which is driven by an impulsive broadband source in the nearEarth magnetotail.