In scenarios of real-time data collection of long-term deployed Wireless Sensor Networks （WSNs）, low-latency data collection with long net- work lifetime becomes a key issue. In this paper, we present a data aggrega...In scenarios of real-time data collection of long-term deployed Wireless Sensor Networks （WSNs）, low-latency data collection with long net- work lifetime becomes a key issue. In this paper, we present a data aggregation scheduling with guaran- teed lifetime and efficient latency in WSNs. We first Construct a Guaranteed Lifetime Mininmm Ra- dius Data Aggregation Tree （GLMRDAT） which is conducive to reduce scheduling latency while pro- viding a guaranteed network lifetime, and then de-sign a Greedy Scheduling algorithM （GSM） based on finding the nmzximum independent set in conflict graph to schedule he transmission of nodes in the aggregation tree. Finally, simulations show that our proposed approach not only outperfonm the state-of-the-art solutions in terms of schedule latency, but also provides longer and guaranteed network lifetilre.展开更多
The system of a true-time delay line for X-band and 8-unit phased array antennas is introduced. Changing the length of a chirp grating with piezotranslator(PZT), the variable delay is obtained. The scheme is applied t...The system of a true-time delay line for X-band and 8-unit phased array antennas is introduced. Changing the length of a chirp grating with piezotranslator(PZT), the variable delay is obtained. The scheme is applied to X-band phased array radar whose searching data rate is 56/s. It is simulated that the beam squinting is influenced by the error of real time delay. The relation between the beamforming mode and its modifying volt is discussed.展开更多
The delay and DVBMT problem is known to be NP-complete. In this paper,an efficient distributed dynamic multicast routing algorithm was proposed to produce routing trees with delay and delay variation constraints. The ...The delay and DVBMT problem is known to be NP-complete. In this paper,an efficient distributed dynamic multicast routing algorithm was proposed to produce routing trees with delay and delay variation constraints. The proposed algorithm is fully distributed,and supports the dynamic reorganizing of the multicast tree in response to changes for the destination. Simulations demonstrate that our algorithm is better in terms of tree delay and routing success ratio as compared with other existing algorithms,and performs excellently in delay variation performance under lower time complexity,which ensures it to support the requirements of real-time multimedia communications more effectively.展开更多
Ignition delay times of China No.3 aviation kerosene were measured behind reflected shock waves using a heated high-pressure shock tube.Experimental conditions covered a wider temperature range of 820-1500 K,at pressu...Ignition delay times of China No.3 aviation kerosene were measured behind reflected shock waves using a heated high-pressure shock tube.Experimental conditions covered a wider temperature range of 820-1500 K,at pressures of 5.5,11 and 22 atm,equivalence ratios of 0.5,1.0 and 1.5,and oxygen concentration of 20%.Adsorption of kerosene on the shock tube wall was taken into account.Ignition delay times were determined from the onset of the excited radical OH emission in conjunction with the pressure profiles.The experimental results of ignition delay time were correlated with the equations:11 0.22 1.09 2 3.2 10 [Keros ene ] [O2] exp(69941 RT) and 7 0.88 0.23 4.72 10 P exp(62092 RT).The current measurements provide the ignition delay behavior of China No.3 aviation kerosene at high pressures and air-like O2 concentration.展开更多
基金This paper was supported by the National Basic Research Pro- gram of China （973 Program） under Crant No. 2011CB302903 the National Natural Science Foundation of China under Crants No. 60873231, No.61272084+3 种基金 the Natural Science Foundation of Jiangsu Province under Ca-ant No. BK2009426 the Innovation Project for Postgraduate Cultivation of Jiangsu Province under Crants No. CXZZ11_0402, No. CX10B195Z, No. CXLX11_0415, No. CXLXll 0416 the Natural Science Research Project of Jiangsu Education Department under Grant No. 09KJD510008 the Natural Science Foundation of the Jiangsu Higher Educa-tion Institutions of China under Grant No. 11KJA520002.
文摘In scenarios of real-time data collection of long-term deployed Wireless Sensor Networks （WSNs）, low-latency data collection with long net- work lifetime becomes a key issue. In this paper, we present a data aggregation scheduling with guaran- teed lifetime and efficient latency in WSNs. We first Construct a Guaranteed Lifetime Mininmm Ra- dius Data Aggregation Tree （GLMRDAT） which is conducive to reduce scheduling latency while pro- viding a guaranteed network lifetime, and then de-sign a Greedy Scheduling algorithM （GSM） based on finding the nmzximum independent set in conflict graph to schedule he transmission of nodes in the aggregation tree. Finally, simulations show that our proposed approach not only outperfonm the state-of-the-art solutions in terms of schedule latency, but also provides longer and guaranteed network lifetilre.
基金Natural Science Foundation from Universities in Jiangsu Province(06KJD510034)
文摘The system of a true-time delay line for X-band and 8-unit phased array antennas is introduced. Changing the length of a chirp grating with piezotranslator(PZT), the variable delay is obtained. The scheme is applied to X-band phased array radar whose searching data rate is 56/s. It is simulated that the beam squinting is influenced by the error of real time delay. The relation between the beamforming mode and its modifying volt is discussed.
文摘The delay and DVBMT problem is known to be NP-complete. In this paper,an efficient distributed dynamic multicast routing algorithm was proposed to produce routing trees with delay and delay variation constraints. The proposed algorithm is fully distributed,and supports the dynamic reorganizing of the multicast tree in response to changes for the destination. Simulations demonstrate that our algorithm is better in terms of tree delay and routing success ratio as compared with other existing algorithms,and performs excellently in delay variation performance under lower time complexity,which ensures it to support the requirements of real-time multimedia communications more effectively.
基金supported by the National Natural Science Foundation of China (Grant No.90916017)
文摘Ignition delay times of China No.3 aviation kerosene were measured behind reflected shock waves using a heated high-pressure shock tube.Experimental conditions covered a wider temperature range of 820-1500 K,at pressures of 5.5,11 and 22 atm,equivalence ratios of 0.5,1.0 and 1.5,and oxygen concentration of 20%.Adsorption of kerosene on the shock tube wall was taken into account.Ignition delay times were determined from the onset of the excited radical OH emission in conjunction with the pressure profiles.The experimental results of ignition delay time were correlated with the equations:11 0.22 1.09 2 3.2 10 [Keros ene ] [O2] exp(69941 RT) and 7 0.88 0.23 4.72 10 P exp(62092 RT).The current measurements provide the ignition delay behavior of China No.3 aviation kerosene at high pressures and air-like O2 concentration.
