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1.
Saeid Salimzadeh 《Journal of Modern Optics》2018,65(17):2017-2024
In this paper, a 3 to 8 optical decoder was proposed using nonlinear photonic crystal ring resonators. For realizing the 3 to 8 decoder, we combined seven 1 to 2 optical decoders. In the proposed structure, X, Y and Z serve as input ports. By combination of these ports, one can control which output port to be ON. The maximum time delay of the proposed structure is about 6?ps. 相似文献
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网络监听(sniffer)是监控网络流量、分析、优化网络的强有力的工具,同时它也是黑客攻击时常用的工具,网络上流动的各种数据流均可通过网络监听的方式来获得,当网络发生异常时,可以通过网络监听来观察分析数据流走向来定位网络异常问题,但同时因为他的平等开放性,使得黑客们也可以截获数据流来获取口令等敏感信息,对于网络监听必须要做到会使用会防范。 相似文献
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The occurrence of autotrophic nitrifiers in the peat from the floors of a natural cypress dome, a cypress dome receiving deep artesian groundwater, and two cypress domes amended with secondary treated sewage effluent, were assessed by surveying their population densities. The absence of ammonium oxidation in the surface waters of the natural dome was due to the low pH and not to any toxic organic chemical effects present in the humic-colored water. This probably explains the low density (0–56 cells cm−3) of autotrophic nitrifiers found associated with the peat from that dome. 相似文献
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Anna V.A. Resurreccion Julie M. Doster Marian Wang W.O. Caster 《The Science of the total environment》1981,20(1):49-56
Weanling male white rats were fed a diet containing a commercially available breakfast cereal. In 28 days they developed a mild anemia coupled with an increased amount of iron in the liver. In parallel work, this same diet was supplemented in a factorial fashion with casein, iron, copper and zinc. The zinc had no effect. Copper supplementation increased the hemoglobin level. Casein decreased liver iron. The copper and casein, when fed together, produced results approaching normal control levels. Supplementation of the diet with additional iron did not increase the hemoglobin or hematocrit but it did further increase iron storage in the liver. It is suggested that cereal enrichment programs might do well to consider copper and protein rather than focus total attention on additional iron and zinc. 相似文献
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Video object segmentation, aiming to segment the foreground objects given the annotation of the first frame, has been attracting increasing attentions. Many state-of-the-art approaches have achieved great performance by relying on online model updating or mask-propagation techniques. However, most online models require high computational cost due to model fine-tuning during inference. Most mask-propagation based models are faster but with relatively low performance due to failure to adapt to object appearance variation. In this paper, we are aiming to design a new model to make a good balance between speed and performance. We propose a model, called NPMCA-net, which directly localizes foreground objects based on mask-propagation and non-local technique by matching pixels in reference and target frames. Since we bring in information of both first and previous frames, our network is robust to large object appearance variation, and can better adapt to occlusions. Extensive experiments show that our approach can achieve a new state-of-the-art performance with a fast speed at the same time (86.5% IoU on DAVIS-2016 and 72.2% IoU on DAVIS-2017, with speed of 0.11s per frame) under the same level comparison. Source code is available at https://github.com/siyueyu/NPMCA-net. 相似文献
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海上油田开发以水平井大斜度井居多,开发井层数多,层间矛盾大。针对目前开发方式无法实现对油层进行精细开采的现状,提出了海上油田液控智能采油工艺技术。该工艺利用八挡位井下液压滑套配合液压解码器可以实现多层的精细开采,同时设计的水嘴结构可以实现多层流量精细的调节与大产液量的调节。井下液压解码器利用排列组合的原理,在降低管线数量的同时,实现了井下层位的选择与高压控制液引导,并通过计算管线摩阻,为现场管线的选择提供了理论支撑。试验结果表明:油嘴结构可以实现0~800 m 3/d的精细调节;井下液压滑套换向功能可靠,换向压力稳定在2 MPa左右,可实现0~2800 m 3/d的产量调节。该工艺不受水深和井斜等限制,最多实现了6层井的精细开采,提高了作业效率,可为海上油田精细化开采提供技术保障,同时也可为深水油田的开发提供技术储备。 相似文献
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本文基于TI的MSP-EXP430FR5739 LaunchPad硬件评估套件和IAR EW430 IDE开发环境,研究了MSP430FR5739型MCU的FRAM分区配置方法,分别采用程序代码关键字声明法及面对复杂应用满足更高定制要求时修改XLINK配置文件法共两种方法实现了分区调配,编写了相应测试程序进行实验,验证结果达到了预期.同时对实际应用中FRAM分区后应进行MPU保护做出阐述,本文提出的方法可用于MSP430FR系列其他型号MCU器件的FRAM调配. 相似文献