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71.
Telemedicine is much more than just teleconferencing. ISDN could be used in some low-end applications, but many telemedicine applications will require the higher bandwidth and guaranteed qualities of service supported by ATM. We discuss the design of multimedia systems for telemedicine. First, various applications of telemedicine are presented, and their multimedia and communications requirements are discussed. A telemedicine prototype is then presented, each of its components discussed, and a potential future telemedicine system is shown 相似文献
72.
Galtarossa A. Yongmin Jung Kim M.J. Lee B.H. Kyunghwan Oh Un-Chul Paek Palmieri L. Pizzinat A. Schenato L. 《Lightwave Technology, Journal of》2005,23(12):4184-4191
Spinning a fiber is the most viable and used technique to reduce polarization mode dispersion (PMD). Many papers have shown that by properly tuning the spin parameters, the differential group delay (DGD) of spun fibers can be greatly reduced. However, the precision with which these optimal profiles are practically implemented may be a problem. In this paper, we perform a statistical analysis of the effects that spin inaccuracy may have on fiber PMD, quantifying how the random uncertainty on spin parameters impairs the DGD. Some preliminary experimental results about spin-induced PMD reduction are also reported. 相似文献
73.
俄罗斯IKZ-2测井仪是一种阵列感应测井仪,具有径向探测范围大、纵向探测分辨率高的优点。仪器结构简洁,性能稳定,在油田勘探中获得巨大的应用价值。本文就其测量系统作全面分析并对应用经验进行总结。 相似文献
74.
We present the architecture of MediaStation 5000 and its applications in medical imaging. As a medical imaging workstation, MediaStation 5000 satisfies the basic requirement of fast image display and processing. All the important image display, manipulation, and processing functions can be executed in real time on 512×512 images, providing instant feedback to the user 相似文献
75.
Chaoyu Yan Yongmin Zhang Yansheng Liu Rui Cao Jinsen Gao Chunming Xu 《Powder Technology》2009,193(1):110-119
The solids mixing in a riser with a height of 10 m and 0.186 m inner diameter was investigated by using pneumatic phosphor tracer technique. Considering the shielding effect of the bed material on the light emitted from the phosphor tracer particle, a modified method for the phosphor tracer measurement is proposed. And then the curves of particle residence time distribution were obtained. The experimental results show that the particle diffusion mechanism can be explained by the dispersions of dispersed particles and particle clusters in the axial direction, and as well the core-annulus nonuniform distribution of the solids fraction in the radial direction of the riser. Moreover, based on the experimental results, a two-dimensional dispersion model was established to predict the solids axial and radial diffusion. Furthermore, the effects of superficial gas velocity and solids circulating flux on the axial and radial Peclet number of the particles were discussed; two empirical correlation formulas about the axial and the radial Peclet numbers were given; the calculated values agree well with the experimental results. 相似文献
76.
77.
移动软交换核心网IP化实现 总被引:2,自引:1,他引:1
张永明 《电信工程技术与标准化》2008,21(11):30-33
随着IP技术的发展,通信网络逐渐向全IP网络发展,基于软交换技术和IP技术构建的下一代核心网成为移动运营商的首选。本文从网络改造架构、话路网组网、IP地址规划方面入手,对于软交换核心网IP化的实现进行了分析和探讨。 相似文献
78.
基于CPFD(Computational particle fluid dynamics)方法,对实验室前期研究的催化裂化管式分配器内的颗粒分配特性及内部流动特性进行了数值模拟,系统研究了输送风、松动风及分配器倾斜角度对颗粒分配不均匀指数的影响,并进一步考察了输送风和松动风对分配器各出口气体流量分布及内部气 固流动特性的影响。结果表明,增大输送风量、松动风量以及分配器的倾斜角度均可以降低颗粒分配不均匀指数,但改变松动风量的效果不如改变输送风量和倾斜角度显著。分配器倾斜角存在一个最优值时,颗粒分配均匀性最佳。输送风的增大会使得颗粒出料量最高的排料口的位置逐渐向分配器的末端移动,中间排料口所流出的气体流量占比增大,末端排料口排风量占比减小。引入松动风后,各出口的颗粒排料量更加接近,同时靠近末端排料口的气体流量占比明显增大。 相似文献
79.
Yang Lu Panpan Li Wenqing Xie Yongmin Duan Xiyang Wang Shiqing Xu Junjie Zhang 《Journal of the European Ceramic Society》2021,41(6):3635-3642
Halide perovskite glass-ceramic has recently moved into the center of the attention of perovskite research due to their potential for temperature sensing. However, quantum dots glass-ceramic with excellent luminescence performance still needs to be combined with rare-earth (RE) ions to accurately measure temperature. In this work, a novel non-RE doped dual-emission (460 nm and 512 nm) CsPbBr3 quantum dots was obtained in telluride glass via the friction crystallization method, where 512 nm was derived from intrinsic luminescence of quantum dots, and 460 nm was originated from thermally induced bromine vacancy, which can be used for temperature sensing. Fluorescence intensity ratio results indicate that the relative sensitivity of dual-emission could reach 5.6 % K?1 at 323 K. The discovery of non-RE doped CsPbBr3 QDs glass-ceramic with negative thermal quenching uncovers a new optional sensing glass material that surpass traditional RE-doped QDs glass by their tunability and sensitivity. 相似文献
80.
Zhou Daojin Cai Zhao Bi Yongmin Tian Weiliang Luo Ma Zhang Qian Zhang Qian Xie Qixian Wang Jindi Li Yaping Kuang Yun Duan Xue Bajdich Michal Siahrostami Samira Sun Xiaoming 《Nano Research》2020,13(1):292-292
Nano Research - The labels in Fig. 8 in the original version of this article were unfortunately misplaced. The corrected figure is as follow. 相似文献