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Non-adiabatic tapered fibers are basic photonic components used in a wide range of applications. Here we investigate a way to increase their utility through the controllable bending of one of their tapered sections. The experiments carried out explain, for the first time, the mechanics of this approach showing how these tapers can be used to build more sensitive sensors. Their use as highly efficient mode converters is also discussed. 相似文献
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以应用ProCAST和MAGMAsoft 2款软件为例,针对铸造工艺仿真设计前处理和过程处理每个环节的主要内容与使用方法进行了较为详细地归纳、分析和总结。提出了处理过程的技术路线,并系统地介绍了每项应用内容的操作平台与使用步骤,从而为高效地应用铸造工艺仿真设计提供理论和技术支持。 相似文献
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Sergio Ayala‐Mar Javier Donoso‐Quezada Roberto C. Gallo‐Villanueva Victor H. Perez‐Gonzalez Jos Gonzlez‐Valdez 《Electrophoresis》2019,40(23-24):3036-3049
Exosomes are nanovesicles secreted by most cellular types that carry important biochemical compounds throughout the body with different purposes, playing a preponderant role in cellular communication. Because of their structure, physicochemical properties and stability, recent studies are focusing in their use as nanocarriers for different therapeutic compounds for the treatment of different diseases ranging from cancer to Parkinson's disease. However, current bioseparation protocols and methodologies are selected based on the final exosome application or intended use and present both advantages and disadvantages when compared among them. In this context, this review aims to present the most important technologies available for exosome isolation while discussing their advantages and disadvantages and the possibilities of being combined with other strategies. This is critical since the development of novel exosome‐based therapeutic strategies will be constrained to the effectiveness and yield of the selected downstream purification methodologies for which a thorough understanding of the available technological resources is needed. 相似文献
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针对高离散精度模型与刀具包围体进行切削计算的情况,由于三维图像重建的计算量大,基于传统CPU实现的数控加工仿真系统不能满足实时性的三维绘制。本文利用GPU的并行性特点,提出并行方式数控仿真切削面显示算法:通过线程并行处理基于MC算法的实体构造模型中体素与刀具包围体的切削计算,根据切削后体素角点信息和边的状态查找建立的构型索引表和交点数目索引表,加速数控仿真切削面的提取,从而提高三维图像的绘制速度,满足实时性显示要求。 相似文献
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景毅 《科技情报开发与经济》2004,14(5):132-133
对处于交变磁场作用下的磁性磨料颗粒的受力和运动规律进行了分析和描述,为交变磁场作用下的磁粒研磨光整加工技术提供了新的思路和工艺选择。 相似文献
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详细地讲解Excellink宏的建立、使用方法及宏函数用法 ,连接MicrosoftExcel和MATLAB的步骤及在Excel中应用MATLAB的方法 ,极大地增强了Excel处理数据的能力和图形输出的能力 ,并用两个实例验证了这个Excellink宏在数据分析过程中所显示的优越性。 相似文献
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Murray Hodgson 《Applied Acoustics》2004,65(1):69-89
The acoustical characteristics of 14 university classrooms at the University of British Columbia were measured before and after renovation—seven of these are discussed in detail here. From these measurements, and theoretical considerations, values of quantities used to assess each classroom configuration were predicted, and used to evaluate renovation quality. Information on each renovation was determined with the help of the university campus-planning office and/or the project acoustical consultant. These were related to the evaluation results in order to determine the relationship between design and acoustical quality. The criteria focused on the quality of verbal communication in the classrooms. Room-average Speech Intelligibility (SI) and its physical correlate, Speech Transmission Index (STI), were used to quantify verbal-communication quality. A simplified STI-calculation procedure was applied. The results indicate that some renovations were beneficial, others were not. Verbal-communication quality varied from ‘poor’ to ‘good’. The effect of a renovation depends on a complex interplay between changes in the reverberation and changes in the signal-to-noise level difference, as affected by sound absorption and the source outputs. Renovations which reduce noise are beneficial unless signal-to-noise level differences remain optimal. Renovations often put too much emphasis on adding sound absorption to control reverberation, at the expense of lower speech levels, particularly at the backs of classrooms. The absorption and noise contributed by room occupants has apparently often been neglected. 相似文献