A brain-computer interface(BCI)-based electric wheelchair control system was developed, which enables the users to move the wheelchair forward or backward, and turn left or right without any pre-learning. This control...A brain-computer interface(BCI)-based electric wheelchair control system was developed, which enables the users to move the wheelchair forward or backward, and turn left or right without any pre-learning. This control system makes use of the amplitude enhancement of alpha-wave blocking in electroencephalogram(EEG) when eyes close for more than 1 s to constitute a BCI for the switch control of wheelchair movements. The system was formed by BCI control panel, data acquisition, signal processing unit and interface control circuit. Eight volunteers participated in the wheelchair control experiments according to the preset routes. The experimental results show that the mean success control rate of all the subjects was 81.3%, with the highest reaching 93.7%. When one subject's triggering time was 2.8 s, i.e., the flashing time of each cycle light was 2.8 s, the average information transfer rate was 8.10 bit/min, with the highest reaching 12.54 bit/min.展开更多
In this paper, we propose the decode-and-forward(DF) based bidirectional wireless information and power transfer(BWIPT) in two-hop relay systems, where the bidirectional relay can decode and forward information from t...In this paper, we propose the decode-and-forward(DF) based bidirectional wireless information and power transfer(BWIPT) in two-hop relay systems, where the bidirectional relay can decode and forward information from the user to the access point(AP), and assist the wireless power transfer from the AP to the user. To maximize the information rate from the user to the AP, we derive the closed form expression of the optimal power splitting(PS) factor, and the time allocation scheme to obtain the optimal time switching(TS) factor. Simulation results show that for both PS and TS protocols, the proposed DF based bidirectional relay systems can improve the information rate as compared with the amplify-and-forward(AF) based bidirectional relay systems.展开更多
A list sphere detector can use a smaller list than commonly believed by employing an appropriate soft output approximation method. Its effect on the "quality" of detector's soft output value is evaluated by measuri...A list sphere detector can use a smaller list than commonly believed by employing an appropriate soft output approximation method. Its effect on the "quality" of detector's soft output value is evaluated by measuring mutual information under ergodic channel. The result shows a length 40 list is adequate for a 4×4 16QAM MIMO system without system-level iteration. For the ergodic channel, the gain of a sphere detector over the linear MMSE detector is dependent on channel coding rate, which answers an important question when sphere detector should he used in system level design. All these theoretical results are then verified by Monte Carlo simulation.展开更多
The bidirectional transfer of information can be realized in an open Heisenberg ferromagnetic spin chain.The information is encoded in the probability distributions of the states at two end spins. The relative entropy...The bidirectional transfer of information can be realized in an open Heisenberg ferromagnetic spin chain.The information is encoded in the probability distributions of the states at two end spins. The relative entropy is used toevaluate the effective transmission of the probability. The evolution of the relative entropy shows a periodical behavior.The period is increased with increasing the length of the chain and the magnetic field while it decreases with increasingthe coupling strength.展开更多
Massive information flows are gen- erated from interactive processing and visua- lizations. To efficiently support information transmission over the Interact, information cen- tric architecture has been recently propo...Massive information flows are gen- erated from interactive processing and visua- lizations. To efficiently support information transmission over the Interact, information cen- tric architecture has been recently proposed. In this paper, we consider an information centric architecture, called the data centric networking architecture to provide communication servi- ces to big data, where a service identifier is used to name the data objects. We propose dif- ferent approaches for the dissemination of data objects in a large-scale data centric network. In particular, we propose various approaches to link the data dissemination approach with the topology of the Internet. Further, we eva- luate the proposed approaches with respect to data delivery efficiency, round-trip time imp- rovement, and deployment cost. Based on the results obtained from this study, it can be sh- own that by disseminating data objects to small ISPs, the data delivery efficiency can be significantly improved within an acceptable deployment cost.展开更多
基金Supported by the National Natural Science Foundation of China(No.81222021,No.30970875,No.90920015,No.61172008 and No.81171423)National Key Technology Research and Development Program of the Ministry of Science and Technology of China(No.2012BAI34B02)Program for New Century Excellent Talents in University of the Ministry of Education of China(No.NCET-10-0618)
文摘A brain-computer interface(BCI)-based electric wheelchair control system was developed, which enables the users to move the wheelchair forward or backward, and turn left or right without any pre-learning. This control system makes use of the amplitude enhancement of alpha-wave blocking in electroencephalogram(EEG) when eyes close for more than 1 s to constitute a BCI for the switch control of wheelchair movements. The system was formed by BCI control panel, data acquisition, signal processing unit and interface control circuit. Eight volunteers participated in the wheelchair control experiments according to the preset routes. The experimental results show that the mean success control rate of all the subjects was 81.3%, with the highest reaching 93.7%. When one subject's triggering time was 2.8 s, i.e., the flashing time of each cycle light was 2.8 s, the average information transfer rate was 8.10 bit/min, with the highest reaching 12.54 bit/min.
基金supported in part by the National Natural Science Foundation of China(No.61401330,No.61371127)
文摘In this paper, we propose the decode-and-forward(DF) based bidirectional wireless information and power transfer(BWIPT) in two-hop relay systems, where the bidirectional relay can decode and forward information from the user to the access point(AP), and assist the wireless power transfer from the AP to the user. To maximize the information rate from the user to the AP, we derive the closed form expression of the optimal power splitting(PS) factor, and the time allocation scheme to obtain the optimal time switching(TS) factor. Simulation results show that for both PS and TS protocols, the proposed DF based bidirectional relay systems can improve the information rate as compared with the amplify-and-forward(AF) based bidirectional relay systems.
基金National Natural Science Foundation ofChina(No.60332030)
文摘A list sphere detector can use a smaller list than commonly believed by employing an appropriate soft output approximation method. Its effect on the "quality" of detector's soft output value is evaluated by measuring mutual information under ergodic channel. The result shows a length 40 list is adequate for a 4×4 16QAM MIMO system without system-level iteration. For the ergodic channel, the gain of a sphere detector over the linear MMSE detector is dependent on channel coding rate, which answers an important question when sphere detector should he used in system level design. All these theoretical results are then verified by Monte Carlo simulation.
基金Supported by the National Natural Science Foundation of China under Grant No. 10774108
文摘The bidirectional transfer of information can be realized in an open Heisenberg ferromagnetic spin chain.The information is encoded in the probability distributions of the states at two end spins. The relative entropy is used toevaluate the effective transmission of the probability. The evolution of the relative entropy shows a periodical behavior.The period is increased with increasing the length of the chain and the magnetic field while it decreases with increasingthe coupling strength.
基金supported by the National Science and Technology Major Projects of the Ministry of Science and Technology of China under Grant No.2012ZX03005003the State Key Program of National Natural Science of China under Grant No.61232017+3 种基金the National Basic Research Program of China(973 Program)under Grant No.2013CB329101the National Natural Science Foundation of China under Grants No.61102049,No.61271202the Beijing Natural Science Foundation underGrants No.4132053,No.4122060the Scientific Research Foundation of the Returned Overseas Chinese Scholars of State Education Ministry under Grant No.W13C300010
文摘Massive information flows are gen- erated from interactive processing and visua- lizations. To efficiently support information transmission over the Interact, information cen- tric architecture has been recently proposed. In this paper, we consider an information centric architecture, called the data centric networking architecture to provide communication servi- ces to big data, where a service identifier is used to name the data objects. We propose dif- ferent approaches for the dissemination of data objects in a large-scale data centric network. In particular, we propose various approaches to link the data dissemination approach with the topology of the Internet. Further, we eva- luate the proposed approaches with respect to data delivery efficiency, round-trip time imp- rovement, and deployment cost. Based on the results obtained from this study, it can be sh- own that by disseminating data objects to small ISPs, the data delivery efficiency can be significantly improved within an acceptable deployment cost.