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101.
102.
随着Internet用户和可上网的终端数量的激增 ,IP地址空间日趋枯竭 ,IP地址的扩充需求也愈加迫切。新一代寻址方案IPv6将成为未来因特网的主流协议。 相似文献
103.
提出种基于TEMIC射频卡Manchester编码的速率自适应读卡算法,并对该算法进行了说明和示例。 相似文献
104.
通过对佳木斯有线网络的分析,意识到佳木斯有线网络面临的机遇和存在的问题,分析了网络的现状,并根据当地的生活水平提出了目前应采取的解决方案。 相似文献
105.
106.
Fengyuan Ren Xunhe Yin Xiaomeng Huang Chuang Lin 《Communications Letters, IEEE》2006,10(12):858-860
Active queue management (AQM) is proposed to enhance end-to-end congestion control through purposefully dropping packets in the intermediate nodes. In this letter, a novel packet dropping mechanism is developed through designing a binary controller applying the robust control theory. The new mechanism can simplify the manipulation on the AQM router so as to be helpful for implementing the high performance router. The numerical simulation results show that the binary controller can satisfy with the technical requirements for AQM 相似文献
107.
Haluk E. Karaca Ibrahim Karaman Burak Basaran Yang Ren Yuny I. Chumlyakov Hans J. Maier 《Advanced functional materials》2009,19(7):983-998
Magnetic shape memory alloys (MSMAs) have recently been developed into a new class of functional materials that are capable of magnetic‐field‐induced actuation, mechanical sensing, magnetic refrigeration, and energy harvesting. In the present work, the magnetic &!hyphen;field‐induced martensitic phase transformation (FIPT) in Ni45Mn36.5Co5In13.5 MSMA single crystals is characterized as a new actuation mechanism with potential to result in ultra‐high actuation work outputs. The effects of the applied magnetic field on the transformation temperatures, magnetization, and superelastic response are investigated. The magnetic work output of NiMnCoIn alloys is determined to be more than 1 MJ m?3 per Tesla, which is one order of magnitude higher than that of the most well‐known MSMAs, i.e., NiMnGa alloys. In addition, the work output of NiMnCoIn alloys is orientation independent, potentially surpassing the need for single crystals, and not limited by a saturation magnetic field, as opposed to NiMnGa MSMAs. Experimental and theoretical transformation strains and magnetostress levels are determined as a function of crystal orientation. It is found that [111]‐oriented crystals can demonstrate a magnetostress level of 140 MPa T?1 with 1.2% axial strain under compression. These field‐induced stress and strain levels are significantly higher than those from existing piezoelectric and magnetostrictive actuators. A thermodynamical framework is introduced to comprehend the magnetic energy contributions during FIPT. The present work reveals that the magnetic FIPT mechanism is promising for magnetic actuation applications and provides new opportunities for applications requiring high actuation work‐outputs with relatively large actuation frequencies. One potential issue is the requirement for relatively high critical magnetic fields and field intervals (1.5–3 T) for the onset of FIPT and for reversible FIPT, respectively. 相似文献
108.
Shijie Ren Chao Yan Doojin Vak David J. Jones Andrew B. Holmes Wallace W. H. Wong 《Advanced functional materials》2012,22(10):2015-2026
Molecular organization behavior and visible light absorption ability are important factors for organic materials to be used in efficient bulk heterojunction solar cells applications. In this context, a series of monosubstituted fluorenyl hexa‐peri‐hexabenzocoronene (FHBC) are synthesized with the aim to combine the self‐association property of the FHBC unit with broadened light absorption of a small molecule organic dye, bisthienylbenzothiadiazole (TBT). Optical and electrochemical properties of the FHBC compounds vary according to their structures. Introduction of a TBT unit into the FHBC system broadens the absorption. All of the FHBC compounds show strong π–π intermolecular association in solution. X‐ray scattering measurements on thermally extruded filaments and thin films showed ordered alignment of these compounds in the solid state. In atomic force microscopy experiments, nanoscale phase separation is observed in thin films of FHBC and fullerene derivative blends. Solar cell devices with these compounds as donors are fabricated. FHBC compounds with the TBT unit show higher short circuit current while the high open circuit voltages are maintained. With C60 derivative as acceptor, power conversion efficiency of 1.12% is achieved in the unoptimized solar cell devices under simulated solar irradiation. The efficiency was further improved to 1.64% when C70 derivative was used as the acceptor. 相似文献
109.
Zhiqiang Niu Wenjun Ma Jinzhu Li Haibo Dong Yan Ren Duan Zhao Weiya Zhou Sishen Xie 《Advanced functional materials》2012,22(24):5209-5215
A critical challenge in nanocomposite fabrication by adding SWCNTs as reinforcement is to realize an effective transfer of the excellent mechanical properties of the SWCNTs to the macroscale mechanical properties of the matrix. Using directly grown SWCNT films with continuous reticulate structure as the template, Cu/SWCNTs/Cu laminated nanocomposites are fabricated by an electrodepositing process. The resulting Cu/SWCNTs/Cu laminated nanocomposites exhibit extremely high strength and Young's modulus. The estimated Young's modulus of the SWCNT bundles in the composite are between 860 and 960 GPa. Such a high strength and an effective load‐transfer capacity are ascribed to the unique continuous reticulate architecture of SWCNT films and the strong interfacial strength between the SWCNTs and Cu matrix. Raman spectroscopy is used to characterize the loading status of the SWCNTs in the strained composite. It provides a route to investigate the load transfer of SWCNTs in the metal matrix composites. 相似文献
110.
激光冲击对中高温服役条件下镍基合金K417显微硬度的影响 总被引:1,自引:0,他引:1
为研究中高温环境下的激光冲击强化效果,采用功率密度8.5GW/cm2、脉冲宽度10ns的强激光对K417镍基合金冲击改性,利用维氏硬度法测试其在700℃、800℃、900℃保温后的显微硬度值。结果表明中高温保温后,激光冲击硬化效果有所减弱,但不同温度下激光冲击区域的平均硬度均明显大于未冲击区域;深度方向硬度近似呈指数形式衰减,硬化层深度随温度的增加呈减小趋势;单个光斑径向硬度分布与激光空间分布特性导致的等离子体冲击波不均匀相关。研究表明在800℃以下,激光冲击有效提高了K417的综合性能指标。 相似文献