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91.
Li  Yixiang  An  Huanxiao  Wang  Xiaobing  Wang  Pan  Qu  Fei  Jiao  Yan  Zhang  Kun  Liu  Quanhong 《Nano Research》2018,11(2):1038-1056
Nano Research - Applying ultrasound (US) to drug delivery and disease therapy is important work. Sonodynamic therapy (SDT)—a comprehensive therapy using US and a sonosensitizer—exhibits...  相似文献   
92.
在目前的原燃料条件下,为保证马钢2500m3高炉炉渣具有良好的流动性和较高的脱硫能力,炉渣的CaO/SiO2应控制在1.05至1.15之间,炉渣温度不低于1450℃.  相似文献   
93.
Pancreatic cancer is a highly aggressive and treatment-refractory cancer. A clinically-relevant animal model is necessary to develop therapy for metastatic pancreatic cancer. In this study we evaluated the efficacy of mitomycin C (MMC) and 5-FU against the human pancreatic adenocarcinoma cell line PAN-12 in an orthotopic human metastatic pancreatic cancer nude mice model. The model is constructed by surgical orthotopic implantation (SOI) of histologically intact tumor tissue in the tail portion of the pancreas near the spleen. PAN-12 grew very aggressively in the control group of nude mice with extensive local invasion and distant metastasis to various organs with a propensity for the lung but to other organs as well, including the liver, kidney and regional and distant lymph nodes. In a striking effect none of the mice in the MMC-treated group developed tumor. Although mice in the 5-FU treated group survived statistically significantly longer than those in the untreated control, the overall incidence of metastasis in these mice was equivalent to those in the control. However no liver or kidney metastases were found in the 5-FU treated animals perhaps accounting in part for their longer survival. This "clinical" nude mouse model of highly metastatic pancreatic cancer can now be used to discover new effective agents for this disease.  相似文献   
94.
通过对某钢厂冷轧电气传动系统分析,合理选取检测信号,构建了基于组态的实时在线监测系统,实现实时数据显示、报警、样本数据的存储、数据采集、参数设定等功能。利用MATLAB的Simulink工具构建了冷轧传动中的三相异步电动机故障诊断仿真系统。将RBF神经网络技术应用于冷轧电气传动系统的故障诊断,设计了基于RBF网络的三相异步电动机故障诊断系统。通过对训练好的网络进行验证,证明所设计的诊断方法能够对传动系统中的电动机故障进行很好的预测和判断,具有良好的实际应用前景。  相似文献   
95.
The flourish of P2P systems draws a lot of attention of networking researchers. Some research efforts focus on P2P systems, trying to understand the mechanism of various implementations and the behavior pattern of P2P users, and then improve the systems?? performance. Others look at the issue from the angle of ISPs, trying to help ISPs solve various issues brought by P2P applications. In this article, we conduct a review study on recent research efforts in these two areas. The first part of this article focuses on several key strategies that have significant influence on the performance of P2P systems. In the second part, we review some important techniques for ISPs to manage P2P traffic, i.e., blocking, caching and localization, and compare their advantages and disadvantages.  相似文献   
96.
Tissue dynamics spectroscopy combines dynamic light scattering with short-coherence digital holography to capture intracellular motion inside multicellular tumor spheroid tissue models. The cellular mechanical activity becomes an endogenous imaging contrast agent for motility contrast imaging. Fluctuation spectroscopy is performed on dynamic speckle from the proliferating shell and hypoxic core to generate drug-response spectrograms that are frequency versus time representations of the changes in spectral content induced by an applied compound or an environmental perturbation. A combination of 28 reference compounds and conditions applied to rat osteogenic UMR-106 spheroids generated spectrograms that were crosscorrelated in a similarity matrix used for unsupervised hierarchical clustering of similar compound responses. This work establishes the feasibility of tissue dynamics spectroscopy for three-dimensional tissue-based phenotypic profiling of drug response as a fully endogenous probe of the response of tissue to reference compounds.  相似文献   
97.
针对水厂仪表可集成度低和网络兼容性差的缺点,设计了一种多网络融合的水厂自动化控制系统。系统节点选用Microchip公司基于M4K内核的处理器PIC32MX795F512L,使用该芯片内置的多种网络接口与仪表/设备互连,并给出了硬件方案、工业以太/CAN网络冗余算法和异构网络的数据帧协议。该系统网络平台融合了安防等其他...  相似文献   
98.
Liping An  Lingyun Tong 《Knowledge》2010,23(6):555-562
Rough sets theory has proved to be a useful mathematical tool for dealing with the vagueness and granularity in information tables. Classical definitions of lower and upper approximations were originally introduced with reference to an indiscernibility relation. However, indiscernibility relation is still restrictive for many applications. Many real-world problems deal with assignment of some objects to some preference-ordered decision classes. And, the objects are described by a finite set of qualitative attributes and quantitative attributes. In this paper, we construct the indiscernibility relation for the subset of nominal attributes, the outranking relation for the subset of ordinal attributes, and the similarity relation for the subset of quantitative attributes. Then the global binary relation is generated by the intersection of indiscernibility relation, outranking relation and similarity relation. New definitions of lower and upper approximations of the upward and downward unions of decision classes are proposed based on the global relation. We also prove that the lower and upper approximation operations satisfy the properties of rough inclusion, complementarity, identity of boundaries, and monotonicity.  相似文献   
99.
This paper investigates robust observer‐controller compensator design using Vidyasagar's structure (VS). VS has a unit matrix parameter H similar to the Q parameter for the Youla–Kucera parameterization. VS can be designed based on the left coprimeness of the central controller in the H‐loop shaping design procedure (H‐LSDP) and therefore can preserve the intrinsic properties of the H‐LSDP. This paper introduces algebraic methods to simplify the design of H in the VS controller by solving specific algebraic equations. In particular, the algebraic design of H can achieve two things. First, a dynamic H adjusts the tracking performance and yields the integral action. Second, a dynamic H rejects the input and output sinusoidal disturbances with known frequencies. These attributes are indications of the flexibility of the proposed method since the output‐feedback controller design of the H‐LSDP cannot easily deal with such conditions. This paper discusses the achieved loop and the closed‐loop behavior of the system with VS, and also gives two numerical examples. The first example shows that the proposed method results in a better design in many aspects than the resulting from H‐LSDP. The second example shows the application of the proposed method to rejecting input and output step disturbances, and input and output multiple sinusoidal disturbances, for which the H‐LSDP can hardly be used. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
100.
Abstract— The development of a compact, efficient VGA projection module to be embedded in mobile devices is reported. The design incorporates laser/laser diode (LD) light sources, Schlieren optics, and a one‐dimensional diffractive spatial optical modulator (SOM). During development, the optical parameters were determined and the relationships between the parameters to optimize the optical specifications were derived. The resulting optimized specifications enable us to manufacture two types of optical modu les as compact as 13 cc and with as little as 10% speckle contrast ratio.  相似文献   
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