The power communicationnetworks is a relatively complex system with high security, which is performed in a number of ways, such as safety of power generation equipment, security of transmission and distribution lines...
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In this paper, based on the feedback free distributed video coding system, a rate control algorithm was proposed for Wyner-Ziv frames. First, calculate the maximum correlation of coefficient band level between the sou...
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wireless Body Area network (WBAN) is considered as a special type of WSN. It consists of low-power wirelesssensor nodes, which are placed on or implanted in the body for continuous health monitoring. MAC protocol is ...
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ISBN:
(纸本)9781510821279
wireless Body Area network (WBAN) is considered as a special type of WSN. It consists of low-power wirelesssensor nodes, which are placed on or implanted in the body for continuous health monitoring. MAC protocol is responsible for conflict detection, processing, priority control, timeslot assignment, transmission order etc. So the design of MAC protocol plays an important role in the reliability and efficiency of WBAN. In order to increase the energy efficiency and reliability of WBAN, a new wireless body area network MAC protocol-AD-MAC protocol is proposed. The proposed protocol adopts dynamic priority control, dynamic timeslot allocation mechanism and dynamic length allocation mechanism of different access periods to achieve reliable transmission in the situation of low latency and low power consumption. The simulation results show that AD-MAC protocol is superior to IEEE802.15.6 MAC and CA-MAC in terms of throughput, power consumption and delay.
B+ Tree is a special balanced multiway tree with flexible structure and node pages linking to each other. It supports not only rapid random query, but also range query. But B+ Tree index cannot be directly migrated si...
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Cooperative spectrum sensing (CSS) is a keytechnology to improve the sensing performance. Fully distributed CSS has been applied in cognitive radio ad hoc networks with good detection performance. However, when the n...
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Ghost imaging could be used to make a quick identification of orthogonal objects by means of photocurrent correlation measurements. In this paper, we extend the method to identify nonorthogonal objects. In the method,...
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Ghost imaging could be used to make a quick identification of orthogonal objects by means of photocurrent correlation measurements. In this paper, we extend the method to identify nonorthogonal objects. In the method, an object is illuminated by one photon from an entangled pair, and the other one is diffracted into a particular direction by a pre-established multiple-exposure hologram in the idler arm. By the correlation measurements, the nonorthogonal object in the signal arm could be discriminated within a very short time. The constraints for the identification of nonorthogonal objects are presented, which show that the nonorthogonal objects can be discriminated when the overlapping portion between any two objects is less than half of all the objects in the set. The numerical simulations further verify the result.
Aimed at the problems that data access delay and static index structure cannot meet the demand of frequent index update in the massive network management data,a dynamic index mechanism based on HBase and a special ind...
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Aimed at the problems that data access delay and static index structure cannot meet the demand of frequent index update in the massive network management data,a dynamic index mechanism based on HBase and a special index table is designed in this *** key value of the table is comprised of key value and indexed column which come from original data,thus enforcing the map of the indexed column with the original *** address the problems in frequently adding and deleting data,an index update algorithm is established in which only changed data is *** results show that the index structure will be adjusted as the data is adding and deleting,rustling in the optimal search *** query efficiency based on the improved method raises 4.98 times in 100 thousand rows and 55.66 times in 1 million *** more the number of the rows increases,the more search efficiency obviously improves.
Face recognition research mainly focuses on traditional 2D color images, which is extremely susceptible to be affected by external factors such as various viewpoints and has limited recognition accuracy. In order to a...
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Face recognition research mainly focuses on traditional 2D color images, which is extremely susceptible to be affected by external factors such as various viewpoints and has limited recognition accuracy. In order to achieve improved recognition performance, as well as the 3D face holds more abundant information than 2D, we present a 3D human face recognition algorithm using the Microsoft's Kinect. The proposed approach integrates the depth data with the RGB data to generate 3D face raw data and then extracts feature points, identifies the target via a two-level cascade classifier. Also, we build a 3D-face database including 16 individuals captured exclusively using Kinect. The experimental results indicate that the introduced algorithm can not only achieve better recognition accuracy in comparison to existing 2D and 3D face recognition algorithms when the probe face is exactly in front of Kinect sensor, but also can increase 9.3% of recognition accuracy compared to the PCA-3D algorithm when it is not confronting the camera.
In view of the existing web site credibility evaluation models failing to comprehensively consider the multiple attributes of trust,after learning the D- S evidence theory and fuzzy theory,a new web site credibility e...
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ISBN:
(纸本)9781510805750
In view of the existing web site credibility evaluation models failing to comprehensively consider the multiple attributes of trust,after learning the D- S evidence theory and fuzzy theory,a new web site credibility evaluation model is put forward in which the trust value is divided into historical trust value and the current trust *** study shows that the model can track the change of user preferences in real-time as well as can meet the dynamic nature of universal environment,so the trust assessment is more reasonable and accurate.
In this paper, we present a two-hop-relay WCDMA cellular system with queueing capability, where a call can wait in the incoming buffer at the congested Base Transceiver Station (BTS) if no channel is immediately avail...
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ISBN:
(纸本)9781849199940
In this paper, we present a two-hop-relay WCDMA cellular system with queueing capability, where a call can wait in the incoming buffer at the congested Base Transceiver Station (BTS) if no channel is immediately available, so as to reduce the call blocking rate. We develop an analytic model based on Multidimensional Markov chains. Then based on this model, we can obtain the average transmission rate and the queuing delay performance of the system respectively. Finally, through numerical calculation, we analyze the impact of the various parameters on the performance of the two-hop-relay WCDMA cellular system with queueing capability.
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