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Search Results: 1 - 10 of 51910 matches for " 祝连庆 "
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单层4路90°相位差功率分配器
A single-layer four-way power divider with 90° phase differences

,,刘锋
- , 2015, DOI: 10.11860/j.issn.1673-0291.2015.05.05
Abstract: 摘要 提出了一种新型的单层4路功率分配器.它具有各端口理想的阻抗匹配和隔离特性及相邻输出端口间90°的相位差.它由3个环形电路组成,这些环形电路均由4段传输线段和1个电阻构成.通过经典的奇偶模分析技术,得到了该模型的闭式计算公式.为了验证该设计的有效性,将其在1 GHz工作频率上进行了两次建模仿真.仿真结果表明:提出的功率分配器可以有效地产生具有90°相位差的4路输出,具有很强的工程实用性和通用性.
Abstract: A novel single-layer four-way power divider is proposed. It features perfect matching and isolation performance for every port and 90°phase difference between adjacent two outputs.It is constructed through the combination of three ring circuits which consist of four transmission lines sections and a resister.By the classical even-and odd-mode analysis technique, the closed-form design equations are derived. To demonstrate the validity of this design, two simulations are implemented at 1GHz. The results of simulation show that the proposed power divider can effectively produce four outputs with 90° phase differences and has a strong engineering practicality and generality.
基于 t 分布邻域嵌入算法的流式数据自动分群方法
Automatic clustering method of flow cytometry data based on t-distributed stochastic neighbor embedding

孟晓辰,王玥,
- , 2018, DOI: 10.7507/1001-5515.201802037
Abstract: 流式细胞仪中多参数流式数据分群传统方法主要是利用专业软件采取人工设门方式,圈出目标细胞进行分析,分析过程较为复杂,专业性较强。基于此,本文提出了一种基于 t 分布邻域嵌入(t-SNE)算法对多参数流式数据进行分群处理。该算法将样本数据在高维空间中的欧几里德距离转化为条件概率来表征相似性,使数据降到低维空间。本文通过使用流式细胞仪处理染色后的人体外周血细胞,并将处理后的数据导出作为实验样本数据,对其利用 t-SNE 算法进行降维,并与核主成分分析(KPCA)降维算法对比,分别使用 K 均值(K-means)算法对降维得到的主成分数据进行分类。结果表明,t-SNE 算法对呈非对称且有拖尾分布的细胞类群具有很好的分群效果,分群准确率可达 92.55%,或可有助于多色多参数流式数据进行自动分析。
The traditional method of multi-parameter flow data clustering in flow cytometry is to mainly use professional software to manually set the door and circle out the target cells for analysis. The analysis process is complex and professional. Based on this, a clustering algorithm, which is based on t-distributed stochastic neighbor embedding (t-SNE) algorithm for multi-parameter stream data, is proposed in the paper. In this algorithm, the Euclidean distance of sample data in high dimensional space is transformed into conditional probability to represent similarity, and the data is reduced to low dimensional space. In this paper, the stained human peripheral blood cells were treated by flow cytometry, and the processed data were derived as experimental sample data. Thet-SNE algorithm is compared with the kernel principal component analysis (KPCA) dimensionality reduction algorithm, and the main component data obtained by the dimensionality reduction are classified using K-means algorithm. The results show that thet-SNE algorithm has a good clustering effect on the cell population with asymmetric and trailing distribution, and the clustering accuracy can reach 92.55%, which may be helpful for automatic analysis of multi-color multi-parameter flow data.
基于双通道M-Z干涉仪的FBG光开关研究
Research of Optical Switch Based on Dual-pass Tunable Mach-Zehnder Interferometer

闫光,何巍,杨润涛,
- , 2016, DOI: 10.16450/j.cnki.issn.1004-6801.2016.04.030
Abstract: 为降低电光开光的插入损耗并提高性能,提出了一种基于双通道可调谐马赫-曾德(M-Z)干涉仪制作的光纤布拉格光栅(fiber Bragg grating,简称FBG)光开关,通过改变干涉仪中的可调电动光纤延迟线的延迟时间,实现滤波谱周期的可调谐。通过改变干涉仪其中一臂的延迟时间设定,该光开关能够实现对设定波长光波的开关功能。对光纤M-Z干涉滤波原理进行了理论分析,使用C波段宽带放大自发辐射光源对双通道可调M-Z干涉仪的性能进行了测试。结果表明,其可实现大范围及高精度的滤波调节功能。对基于双通道可调谐马赫-曾德干涉仪制作的FBG光开关,通过FBG开关性能检测系统实验,得到该光开关在波长为1 550 nm处的输出光谱,光开关的消光比达到25 dB。结果表明,该光开关能够实现大范围高精度滤波功能,具有高消光比、结构简单和易于调节等优点。
In order to improve performance and reduce the insertion losses of electro-optic switches, a fiber Bragg grating(FBG) optical switch was designed based on a dual-pass tunable Mach-Zehnder interferometer. The filtering cycle spectrum was tunable by changing the delay time of the electric adjustable fiber delay line in the interferometer. The filter principle of the optical fiber M-Z interferometer was analyzed and tested with the C-band broadband light, and the results show that it can achieve a wide range and high-precision filter adjustment function. The interferometer was also tested as a FBG optical switch. The output spectrum at a wavelength of 1550 nm was obtained through a FBG optical switch performance testing system experiment. Its side mode suppression ratio was over 25 dB. Test results show that it can achieve a large range and fine filter, and that the optical switch also has advantages of a high extinction ratio, simple structure, and easy adjustability.
修井机地锚桩抗拔承载能力试验研究
冯志鹏,常玉,邹龙,付海龙,
地震工程与工程振动 , 2014, DOI: 10.13197/j.eeev.2014.06.243.fengzp.030
Abstract: 地锚桩经由绷绳与井架相连,是修井时固定安放修井井架的重要组成部分,其桩基抗拔承载力直接关系到修井作业和人员安全.大庆油田现用地锚桩主要形式为普通油管桩,其极限承载力主要为桩侧摩阻力.为使修井地锚桩具有足够的承载力以保证修井安全,运用振动和机械阻抗测试方法,对不同土况下桩承载力进行试验,通过计算机械导纳和动刚度,得到大庆油田采油区域地锚桩承载能力与土质条件的关系黏土桩承载力最大,砂土次之,低洼湿地和建筑回填土较差.解释了地锚桩拔桩过程中桩土作用机理和侧摩阻力非线性变化规律.采用直接拔桩方法对测试结果进行验证,说明机械阻抗法可推广应用于此类等截面抗拔桩的承载力研究,为油田地锚桩安全施工提供理论依据.
含口盖复合材料圆柱壳轴压屈曲性能分析
闫光,韩小进,闫楚良,
吉林大学学报(工学版) , 2015,
Abstract: 对完整复合材料圆柱壳进行了轴向压缩破坏试验,得到了圆柱壳的载荷-应变曲线和破坏载荷,试验结果表明:在轴压载荷作用下,圆柱壳的破坏形式为屈曲破坏。结合ANSYS有限元软件对复合材料圆柱壳进行屈曲分析,有限元计算结果与试验结果一致,验证了模型和计算方法的有效性。利用所建立的模型,对圆柱壳的铺层顺序进行改进设计,分析了铺层角度对开口圆柱壳屈曲载荷的影响。在开口处加装复合材料口盖进行补强,计算了不同口盖铺层方式下的柱壳屈曲强度。计算结果表明:优化复合材料叠层顺序可提升结构的屈曲载荷,开口后圆柱壳的轴向屈曲载荷大幅降低,加装口盖可使开口圆柱壳的轴向稳定性得到有效的增强。提出了一种提高含口盖的复合材料圆柱壳轴向屈曲强度的改进设计方法,为复合材料壳体的稳定性设计提供参考。
流式细胞仪液流自洁系统设计
Design of Flow Cytometry Self-cleaning System

王海军,郭阳宽,,孟晓辰
- , 2016, DOI: 10.7507/1001-5515.20160095
Abstract: 流动室堵塞是流式细胞仪使用中常见的问题,可造成检测误差或检测失败。本文根据流动聚焦原理,分析了流动室堵塞时的压力变化情况,据此提出了通过检测样本流压力升高判断流动室堵塞,并利用液体反冲疏通被堵塞流动室的方法,设计并搭建了实验系统。实验表明,该方法可以有效解决流动室堵塞问题。
In order to solve the problem of the micro flow cell clogging, and to improve the reliability of the flow cytometry system, a new method was proposed for hydrodynamic self-cleaning system. By analyzing the flow cell focus principle, we considered that to obtain stable single cell flow, the stable pressure in the flow chamber must be ensured. Therefore, we established a diagnosis method of clogging by the pressure detecting, and designed a self-cleaning system. Then we built up corresponding experimental systems. Experiments and testing showed that the self-cleaning system could improve the flow and resolve the clogging problem.
基于核主成分分析的流式细胞数据分群方法研究
Cell data clustering method in flow cytometry based on kernel principal component analysis

马闪闪,董明利,张帆,潘志康,
- , 2017, DOI: 10.7507/1001-5515.201604088
Abstract: 针对多参数流式细胞数据分析过程复杂、自动化程度不高、要求操作者具有一定专业背景等问题,本文提出了一种基于核主成分分析算法(KPCA)进行多参数流式细胞数据分群的方法。利用 KPCA 对多参数流式细胞数据进行非线性变换,降低数据的维度,得到主成分特征变量下的散点图分群结果,并使用改进的K-means 聚类算法实现不同亚群的自动设门。以人体外周血淋巴细胞样本检测结果为实验数据,分别对其进行传统分群、主成分分析(PCA)分群、KPCA 分群处理,并对特征参数的选取进行了探索。结果表明,KPCA 方法能够较好地应用于多参数流式细胞数据分析中,与传统细胞分群方法相比,该方法无需操作者具备专业知识,即可实现快速准确的自动分群,能够提高流式细胞仪临床诊断分析的效率。
The process of multi-parametric flow cytometry data analysis is complicate and time-consuming, which requires well-trained professionals to operate on. To overcome this limitation, a method for multi-parameter flow cytometry data processing based on kernel principal component analysis (KPCA) was proposed in this paper. The dimensionality of the data was reduced by nonlinear transform. After the new characteristic variables were obtained, automatical clustering can be achieved using improvedK-means algorithm. Experimental data of peripheral blood lymphocyte were processed using the principal component analysis (PCA)-based method and KPCA-based method and then the influence of different feature parameter selections was explored. The results indicate that the KPCA can be successfully applied in the multi-parameter flow cytometry data analysis for efficient and accurate cell clustering, which can improve the efficiency of flow cytometry in clinical diagnosis analysis.
预紧封装光纤光栅温度传感器传感特性研究
Sensing Properties of Fiber Grating Temperature Sensor Package Preload

闫光,辛璟涛,陈昊,骆飞,
- , 2016, DOI: 10.16450/j.cnki.issn.1004-6801.2016.05.023
Abstract: 为了获得稳定测量温度变化的光纤光栅温度传感器,笔者研究带预紧力的光纤光栅温度传感器的封装技术及其传感特性。通过温度传感理论分析,在避免光纤光栅对温度和应变的交叉敏感情况下,对光纤光栅温度传感器进行有限元Ansys应力分布进行模拟,可知本封装具有一定的减敏作用,温度测量量程增大,满足更多实际工程中的使用。环氧树脂DP420将带有预紧力光纤光栅封装在铍青铜材料的圆柱体内,在恒温鼓风干燥箱对光纤光栅温度传感器进行传感特性研究,40~120 ℃的范围内,每次升温5 ℃。所得结果,此光纤光栅温度传感器的温度灵敏度系数为23.81 pm/℃,是裸光纤光栅传感器的2倍,且线性度达0.999以上。 该文对光纤光栅工程化具有较大的应用价值。
In order to obtain a stable measurement of temperature changes and improve the characteristics of a FBG temperature sensor, the packaging technology and sensing properties of fiber grating temperature sensors with preload were studied. Theoretical temperature sensing and stress distribution on the optical fiber grating temperature sensor were analyzed using finite element simulation, and the cross-sensitivity between temperature and fiber grating strain was solved. This package has certain desensitization and a greater range of temperature measurement. The epoxy DP420 adheres fiber grating with preload to the cylinder with beryllium copper material. The sensing properties of the FBG temperature sensor in the oven were studied in a constant temperature blast from 40℃ to 120℃ at intervals of 5℃. The experimental results showed that the temperature sensitivity coefficient of the optical fiber grating temperature sensor was 23.81 pm/℃, which was two times that of the bare FBG sensors, with linearity greater than 0.999.
多层微孔滤膜过滤器

海洋科学 , 1981,
Abstract: 随着微孔滤膜在化学领域中的广泛使用,对过滤器提出了更高的要求,即要提高速度,增大容量;要增强膜的使用寿命;要能对不同粒度的物质分级分离等。为了适应海洋化学研究需要,我们最近试制了一种多层微孔滤膜过滤器(如图示);经试验,性能良好,使用方便,现报道如下。
多层微孔滤膜过滤器

海洋科学 , 1981,
Abstract:
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