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The Optimization of Genetic Algorithm in Wireless Sensor Network Coverage
Wengen Gao,Qigong Chen,Ming Jiang,Yunfei Li,Shinong Wang 보안공학연구지원센터(IJSIP) 2015 International Journal of Signal Processing, Image Vol.8 No.1
According to the maximum coverage problem in wireless sensor networks, GA algorithm combined with the standard processing method can improve the network coverage based on, but there is a risk of falling into local optimum, and costs more computation time. On the condition of analysis and proof of the effectiveness by the employment of normalization processing to resolve coding redundancy of MCSDP, further details of the evaluate conditions are proposed, and new parent selection mechanism is introduced, which both are verified by compared experiments. The experiment results show that the optimization processing method proposed in this paper retains the characteristics of existing methods, and has better optimization performance and improves the network coverage rate as well as calculation speed, which verifies the effectiveness and superiority of the method proposed in this paper.
Yunfei Chen,Qian Shen,Yueyue Wang,Tao Wang,Shaoyan Wu,Ling Zhang,Xu Lu,Fangyuan Zhang,Weimin Jiang,Bo Qiu,Erdi Gao,Xiaofen Sun,Kexuan Tang 한국식물생명공학회 2013 Plant biotechnology reports Vol.7 No.3
Artemisinin is an endoperoxide sesquiterpenelactone isolated from the aerial parts of Artemisia annua L.,and is presently the most potent anti-malarial drug. Owingto the low yield of artemisinin from A. annua as well as thewidespread application of artemisinin-based combinationtherapy recommended by the World Health Organization,the global demand for artemisinin is substantially increasingand is therefore rendering artemisinin in short supply. An economical way to increase artemisinin production is toincrease the content of artemisinin in A. annua. In thisstudy, three key genes in the artemisinin biosynthesispathway, encoding farnesyl diphosphate synthase, amorpha-4, 11-diene C-12 oxidase and its redox partner cytochromeP450 reductase, were over-expressed in A. annuathrough Agrobacterium-mediated transformation. Thetransgenic lines were confirmed by Southern blotting andthe over-expressions of the genes were demonstrated byreal-time PCR assays. The HPLC analysis showed that theartemisinin contents in transgenic lines were increasedsignificantly, with the highest one found to be 3.6-foldhigher (2.9 mg/g FW) than that of the control. Theseresults demonstrate that multigene engineering is aneffective way to enhance artemisinin content in A. annua.
The Method of Aiming towards the Normal Direction for Robotic Drilling
Yuhao Gao,Dan Wu,Yunfei Dong,Xinguo Ma,Ken Chen 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.18 No.6
During the robotic drilling of an aircraft assembly, the normal directions of the workpieces are to be measured to guide the robot by aiming the spindle at the real normal directions of the curved surfaces. This paper describes the development of a method of using four laser displacement sensors to measure the normal direction and the implementation of the proposed method in a robotic drilling system to meet industrial application requirements. First, a novel mechanical structure is introduced to achieve a higher installation accuracy for the laser displacement sensors with a micro adjusting method. Next, the hardware structures and a convenient method of calibrating the sensors are introduced. To accommodate the complexity of the industrial circumstance, a procedure of measuring and adjusting is developed with consideration of both an angular deviation threshold and a limited adjusting iteration. Finally, the experiments of measuring and adjusting iteratively show that two iterations can achieve a satisfactory angular deviation of 0.1° for planar workpieces and three iterations are required for curved workpieces, with the perpendicularity errors of the drilled holes being less than 0.3°. The results can meet the required perpendicularity accuracy of 0.5°.
Wireless Energy-Harvesting Cognitive Radio with Feature Detectors
( Yan Gao ),( Yunfei Chen ),( Zhibin Xie ),( Guobing Hu ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.10
The performances of two commonly used feature detectors for wireless energy-harvesting cognitive radio systems are compared with the energy detector under energy causality and collision constraints. The optimal sensing duration is obtained by analyzing the effect of the detection threshold on the average throughput and collision probability. Numerical examples show that the covariance detector has the optimal sensing duration depending on an appropriate choice of the detection threshold, but no optimal sensing duration exists for the ratio of average energy to minimum eigenvalue detector.
Ming Jiang,Yunfei Li,Yuan Ge,Wengeng Gao,Ke Lou,Shinong Wang,Juanjuan Jiang 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.12
Position information is the foundation of massive applications in Wireless Sensor Network(WSN). Three improved positioning algorithms based on DV-Hop are proposed in order to enhance the positioning accuracy of wireless sensor nodes. First improved algorithm is distance compensation algorithm (DCA) that creates a triangle model to compensate the estimated distance. The second improved algorithm creates a new chain table for all anchor nodes to record and compute the average hop distance. The third improved algorithm is weighting different anchor nodes with anchor nodes’ nearest unknown nodes. The second and third improved algorithms are based on the DCA. The simulation results show that the three improved algorithms are better than the original DV-Hop in localization accuracy. Compared to the original DV-Hop algorithm, the simulation results shows that the three improved algorithms proposed in the paper increase the positioning accuracy of the unknown nodes.
Zhao Bin,Yin Deshun,Gao Yunfei,Ren Jiangtao 한국유변학회 2023 Korea-Australia rheology journal Vol.35 No.3
The rheological property of cathode slurry is commonly influenced by coating speed and mixing temperature, thereby leading to its storage stability and coating uniformity. In this study, the effect of the temperature of slurry on the rheological behaviors is investigated under various shear rates and temperatures based on steady and dynamic tests as well as theoretical models. In the flow experiments, the thixotropic behavior of the slurry is observed at all temperatures tested, and it is reduced with the increase in temperature. The experimental data is captured well by rheological models, and the model parameters are evaluated under the combined effects of shearing and temperature, resulting in two generalized state equations for the description of the flow properties of the slurry. In addition, microstructural rearrangement and polymeric entanglement at high temperatures cause viscosity and modulus to change, giving rise to complex rheological behavior in creep and oscillatory shear. Compared with slurry at 25 and 40 °C, both storage and loss moduli are dependent on oscillatory strain in the range of 0.1–1000% at 65 °C. The difference in characteristic strain corresponding to yielding and strain stiffening behavior is only observed at high temperatures, whereas relaxation times were independent of temperature in the oscillatory shear test. Understanding the effect of the temperature of slurry on rheological behaviors will be useful for improving the manufacturing efficiency of electrodes.
Measurement and Application of Link Reliability for Wireless Mobile Networks
Fuquan Zhang,Inwhee Joe,Demin Gao,Yunfei Liu 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.6
Radio channel characteristics of mobile nodes are quite different compared with the traditional stationary base station to mobile radio channel. Wireless link reliability estimation is necessary for self-organization of wireless mobile multihop networks. In this paper, we measure narrowband path loss measurements in a typical mobile-to-mobile radio environment. For application, we proposed a method to incorporate link reliability into path reliability evaluation and selection for multipath routing in wireless mobile networks. Simulations show that the proposed method has better performance.
An Efficient Multiple-Copy Routing in Intermittently Connected Mobile Networks
Fuquan Zhang,Inwhee Joe,Demin Gao,Yunfei Liu 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.5
PRoPHET (probability routing protocol using history of encounters and transitivity) reduces the invalid copy of message, so that effectively reduce the network overhead and the traffic load in the network. However, the calculation of probability in Prophet does not consider the network conditions. In this paper, we improve the performance of PRoPHET protocol by taking into account connection status to calculate nodes’ encountering probability. The performance of the proposed protocol was analyzed in terms of delivery probability, average delay, and overhead ratio. Numerical results show that the proposed protocol can improve the performance to some extend.
A Survey on Organization and Positioning of Nodes in Wireless Sensor Network
Xinyi Tan,Fuquan Zhang,MengMeng Shi,Demin Gao,Yunfei Liu 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.11
Wireless sensor network has a rapid growth in both science research and commercial development as well as been widely used in a variety of realms. Facing different kinds of challenging issues of WSNs, the deployment of nodes stands out for it has a critical influence on area or target coverage, network connectivity, network lifetime, etc. This paper explores classifications of node and deployment strategies from different angles, weighing their pros and cons and analyzing its impacts on the performance of a WSN.