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1.
无线传感器网络路由中的能量预测及算法实现   总被引:3,自引:0,他引:3  
基于无线传感器网络中路由协议高效合理利用能量的要求,提出一种基于剩余能量预测的地理位置路由(EPGR,energy prediction and geographical routing)算法。算法通过建立传感器网络节点运作模型,及相邻节点剩余能量预测机制,优化路由选择。仿真和分析表明,EPGR算法能够有效地优化数据传输路径,均衡传感器网络节点的能量消耗,延长网络寿命。  相似文献   

2.
以优化网络路由、延长网络生存期为目的,提出了一种基于临时节点的无线体域网(Wireless Body Area Network,WBAN)高效节能路由算法-A WBAN Efficient Energy-saving Routing Scheme Utilizing Temporary Nodes(RSUTN).该算法针对WBAN应用中出现的新的情况,通过充分利用临时节点富余能量,优化网络路由,平衡网络节点间能量消耗,延长网络生存期.理论分析和仿真结果表明,该算法能明显地平衡网络能量消耗,显著地延长网络生存期.  相似文献   

3.
在无线传感器网络中,基于分簇的路由协议对提高网络的寿命有着重要作用,LEACH是一种应用比较广泛的层次路由协议。本文提出一种新的基于最优分簇的无线传感器网络分簇路由(LEACH-O)算法,在簇的形成过程考虑到节点的集中程度和节点的剩余能量,从而减少传感器节点的能量消耗,优化资源利用率。仿真实表明,与传统的LEACH算法相比,该算法配传感器节点间数据传输提供了高效路由,从而延长网络的生命周期。  相似文献   

4.
功率控制下基于能耗最小的Ad hoc网络路由选择算法   总被引:3,自引:3,他引:0  
在节点MAC层发射功率可控情况下,提出了一种基于路径能量消耗最小的路由路径选择算法。该算法根据链路的能量消耗情况来进行路由路径选择,达到节约网络能量的目的。仿真表明.该算法可以动态调整网络路由路径,从而使所选路径的能量消耗达到最小。  相似文献   

5.
具有能量和位置意识基于ACO的WSN路由算法   总被引:4,自引:1,他引:3       下载免费PDF全文
王小明  安小明 《电子学报》2010,38(8):1763-1769
通过融合传感器节点的剩余能量和地理位置信息,设计一种具有传感器节点能量和地理位置意识的基于蚁群优化方法的无线传感器网络路由算法(ELACO);针对路由空洞现象,提出一种路由回退机制,提高了路由搜索成功率.仿真结果表明,ELACO算法具有很高的路由查寻成功率,能够更好地均衡传感器节点能量消耗,从而延长网络使用寿命.  相似文献   

6.
如何高效地利用无线节点的有限能量是移动Ad Hoc网络(MANET)路由协议的一个重要考虑因素.鉴于动态源路由协议(DSR)没有考虑节点的能量限制,本文基于DSR协议提出了一种节能路由算法:MECP-DSR.它采用每报文能量消耗最小作为路由选取标准,并且在发送数据报文时对节点的发射功率进行控制.该文的仿真结果表明,MECP-DSR大大降低了节点的能量消耗,有效提高了移动Ad Hoc无线网络的生存期.  相似文献   

7.
一种基于HEED的簇首多跳融合路由算法   总被引:1,自引:0,他引:1  
姚新兵  王向东 《通信技术》2011,44(4):106-108,111
无线传感器网络节点的能量有限,如何高效使用能量以延长网络寿命成为研究热点之一。针对HEED协议中簇首与基站直接通信能量消耗过大的问题,根据能耗模型与网络模型,提出一种基于HEED的簇首多跳融合路由算法,并用MATLAB在随机分布的传感器网络区域内进行算法的有效性仿真研究。仿真结果表明,新算法相对于HEED算法有效地延长了网络的生命周期。  相似文献   

8.
一种具有能量感知的多路径Ad hoc路由算法   总被引:4,自引:0,他引:4  
该文针对无线移动Ad hoc网络的动态变化拓扑逻辑,存在单向链路,节点能量有限等特点,提出了一种具有能量感知的多路径路由算法。该算法是一种反应式的基于路径池的多路径路由算法,数据和应答消息的路由根据路由池中路径的性能尺度,即跳数、可靠性和剩余能量以一定的概率分布随机选择。路径的可靠性和剩余能量在数据传输过程中动态更新。仿真结果表明该算法能有效地延长网络的生存时间。  相似文献   

9.
针对能量控制和拥塞控制在无线传感器网络路由上的特殊要求,利用蚁群算法(Ant Colony System,ACS)对路由中最短路径加速收敛。为了促使网络节点能量消耗相对均衡,提出一种改进的蚁群路由算法。该算法将多蚁群挥发的信息素与网络节点剩余能量结合成算法控制因子,并且引入了多蚁群竞争机制来避免单一收敛。此算法能有效地控制网络拥塞,并使网络节点能量消耗相对均衡,延长了整个网络的生命周期,实现了高效路由与能量消耗的较优权衡。最后通过Matlab仿真实验验证了该方法的可行性,并给出实验结果。  相似文献   

10.
传感器节点能量的供应一般采用电池,节点能量有限.为了尽可能减少传感器节点通信模块的能量消耗,保证能量供应的持续性,文中提出了一种基于遗传算法的路由算法,不仅降低了单个节点的能量消耗,而且使整个网络能量的消耗更加均衡,从而延长了整个传感器网络的生存周期.  相似文献   

11.
In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal (200) (2d = 0.4027 nm) is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line(w), the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line(x), the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines(y), the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line(z) in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line(q) in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution(λ/△ 2) is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.  相似文献   

12.
High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET > PDMAT > TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.  相似文献   

13.
This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.  相似文献   

14.
An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.  相似文献   

15.
The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO>6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.  相似文献   

16.
Distributed polarization coupling in polarization-maintaining fibers can be detected by using a white light Michelson interferometer. This technique usually requires that only one polarization mode is excited. However, in practical measurement, the injection polarization direction could not be exactly aligned to one of the principal axes of the PMF, so the influence of the polarization extinction ratio should be considered. Based on the polarization coupling theory, the influence of the incident polarization extinction on the measurement result is evaluated and analyzed, and a method for distributed polarization coupling detection is developed when both two orthogonal eigenmodes are excited.  相似文献   

17.
We calculate the Langevin noise sources of self-pulsation laser diodes, analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation, and propose a novel method to restrain the noise effects. A visible SIMULINK model is established to simulate the system, The results indicate that the effects of noise in absorption region can be ignored; that with the increase of DC injecting current, the noise effects enhance power jitter, and nevertheless, the period jitter is decreased; and that with external sinusoidal current modulating the self-pulsation laser diode, the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.  相似文献   

18.
Large-scale synthesis of single-crystal CdSe nanoribbons is achieved by a modified thermal evaporation method, in which two-step-thermal-evaporation is used to control CdSe sources' evaporation. The synthesized CdSe nanoribbons are usually several micrometers in width, 50 nm in thickness, and tens to several hundred micrometers in length. Studies have shown that high-quality CdSe nanoribbons with regular shapes can be obtained by this method. Room-temperature photolumines-cence indicates that the lasing emission at 710 nm has been observed under optical pumping (266 nm) at power densities of 25-153 kW/cm^2. The full width half maximum (FWHM) of the lasing mode is 0.67 nm  相似文献   

19.
By using the expansion of the aperture function into a finte sum of complex Gaussian functions, the corresponding analytical expressions of Hermite-cosh-Gaussian beams passing through annular apertured paraxially and symmetrically optical systems written in terms of ABCD matrix were derived, and they could reduce to the cases with squared aperture. In a similar way, the corresponding analytical expressions of cosh-Gaussian beams through annular apertured ABCD matrix were also given. The method could save more calculation time than that by using the diffraction integral formula directly.  相似文献   

20.
正With the support of 863 programs,Sugon Information Industry Co.,Ltd.,set up a dawning EB-class storage laboratory to address massive data storage requirements and largescale cloud computing demonstration applications.The Dawning EB-class cloud storage system adopts advanced fault-tolerant architecture,efficient data fault-tolerant algorithms with user authentication and data encryption policies to deal with the"lost""wrong"and"stolen"problems of data for ensuring the reliability and safety of the EB-class storage system in the public network application environments.The Dawning EB-class Storage Laboratory taking advan-  相似文献   

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