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1.
The space sheet for a solar array structure is large in dimension, and flexible to induce complex distortion. It is difficult to measure the distortion. A large-scale flexible test prototype system is built for sheet structure vibration monitoring based on the vibration information of the solar array in space. The system provides an intelligent test method for flexible space structure with embedded sensors and non-visualization reinstruction. Multiple fiber Bragg grating （FBG） sensors are packaged and embedded into the structure with spatial division multiplexing （SDM） and wavelength division multiplexing （WDM）. The sensor interrogator distinguishes wavelength shifts that can be turned into curvature of the curve. The structure shape is reconstructed based on the curvature information and the arc-length, and then displayed. The experiment shows that the system has a high FBG sensitivity. The reconstruction algorithm is fast with high precision. The system has great potential for use in health monitoring of the space sheet structure. 相似文献
2.
Rough集是一种处理含糊和不精确性问题的新型数学工具,将其应用于多传感器信息融合中,可以简化规则的描述和表示,有利于快速得到最小融合算法,同时可以解决数据超载问题,形成多传感器信息融合算法. 相似文献
3.
加权融合算法是多传感器数据融合中的常用方法,但加权因子的确定非常困难并直接影响算法的性能.文章提出利用改进的粒子群优化算法对各个传感器的加权因子进行自适应优化,引入种群进化度、聚合度来反映种群的多样性,当种群多样性低于阈值时执行变异操作,并交替使用基于聚合度、进化度的自适应惯性权重函数,从而避免算法陷入局部最优解.通过UCI数据集测例表明本文算法是一种较有效的多传感器数据融合方法,相对其它算法具有较高的融合精度. 相似文献
4.
阐述多传感器信息融合的定义、基本原理、基本框架、融合层次和融合方法,介绍信息融合技术的应用领域,指出信息融合技术存在的问题,最后展望信息融合技术将来的研究方向. 相似文献
5.
A three-step damage identification method based on dynamic characteristics is proposed to improve the structure reliability and security and avoid serious accident. In the proposed method, the frequency and difference of modal curvature （DMC） are used as damage indexes. Firstly, the detection of the occurrence of damage is addressed by the frequency or the square of frequency change. Then the damage location inside the structure is measured by the DMC. Finally, with the stiffness reduction rate as a damage factor, the amount of damage is estimated by the optimization algorithm. The three-step damage identification method has been validated by conducting the simulation on a cantilever beam and the shaking table test on a submerged bridge. The results show that the method proposed in this paper can effectively solve the damage identification problem in theory and engineering practice. 相似文献
6.
INTRODUCTION Structural damage detection technique addresses the problem of how to locate and detect damage that occurred in a structure by using the observed changes of its dynamic and static characteristics. In recent years, damage assessment of structure has drawn wide attention from various engineering fields. Gen-erally, the existing approaches proposed in this area can be clarified into two major categories: the dy-namic identification methods using dynamic test data and the static … 相似文献
7.
降噪处理是分析结构振动信号、提取特征参数、研究损伤识别方法的基础,核独立分量分析(KICA)采用的核方法为结构振动信号的降噪处理提供了新的方法;通过对比KICA与其他算法降噪后信号的HHT边际谱,验证了KICA对低阻尼钢框架结构标准损伤模型降噪的优良性能,特别是提高了对结构安全至关重要的低频振动部分的能量估计的准确度。 相似文献
8.
麻胜兰刘昱昊张铮吴琛 《福建工程学院学报》2020,(1):40-45
考虑到基于2范数的正则化算法存在对结构识别结果过度光滑的效果,提出了基于模态振与L1正则化的损伤识别方法。以—2D简支梁有限元模型为数值算例,比较了使用不同振型数不同损伤程度对损伤识别效果的影响。数值模拟结果表明,对于多损伤工况,当损伤结构的振型数和无损结构的振型数乘积数大于6时,能较好地进行损伤定位,并能对损伤程度给出定性的描述。 相似文献
9.
Arturo Garcia-Perez Juan P. Amezquita-Sanchez Aurelio Dominguez-Gonzalez Ramin Sedaghati Roque Osornio-Rios Rene J. Romero-Troncoso 《浙江大学学报(A卷英文版)》2013,14(9):615-630
Structural health monitoring （SHM） is a relevant topic for civil systems and involves the monitoring, data processing and interpretation to evaluate the condition of a structure, in order to detect damage. In real structures, two or more sites or types of damage can be present at the same time. It has been shown that one kind of damaged condition can interfere with the detection of another kind of damage, leading to an incorrect assessment about the structure condition. Identifying combined damage on struc- tures still represents a challenge for condition monitoring, because the reliable identification of a combined damaged condition is a difficult task. Thus, this work presents a fusion of methodologies, where a single wavelet-packet and the empirical mode decom- position （EMD） method are combined with artificial neural networks （ANNs） for the automated and online identification-location of single or multiple-combined damage in a scaled model of a five-bay truss-type structure. Results showed that the proposed methodology is very efficient and reliable for identifying and locating the three kinds of damage, as well as their combinations. Therefore, this methodology could be applied to detection-location of damage in real truss-type structures, which would help to improve the characteristics and life span of real structures. 相似文献
10.
在分析边缘保持滤波器算法的基础上,应用多传感器数据融合技术,提出了一种新的图像平滑算法。该算法釆用线状掩模窗口和最优融合估计方法,有效地增强了边缘保持能力和去噪能力,克服了边缘保持滤波器存在的缺陷。实验结果表明,该算法性能优于边缘保持滤波器及经典均值滤波器。 相似文献
11.
刘立月 《实验室研究与探索》2011,30(10):46-48,52
从国内外列控系统发展出发,比较分析了各种列车定位技术优缺点,结合高速列车定位趋势,剖析组合定位及GNSS导航特点。在此基础上,提出基于GNSS的高速列车组合定位方案,并对其可靠性、精确性、完整性等关键问题进行了探讨,为高速列车控制过程建模与优化探索新的途径。 相似文献
12.
《天津大学学报(英文版)》2015,(4)
Targeting the non-stationary characteristics of diesel engine vibration signals and the limitations of singular value decomposition(SVD) technique, a new method based on improved local mean decomposition(LMD), SVD technique and relevance vector machine(RVM) was proposed for the identification of diesel valve fault in this study. Firstly, the vibration signals were acquired through the vibration sensors installed on the cylinder head in one normal state and four fault states of valve trains. Secondly, an improved LMD method was used to decompose the non-stationary signals into a set of stationary product functions(PF), from which the initial feature vector matrices can be formed automatically. Then, the singular values were obtained by applying the SVD technique to the initial feature vector matrixes. Finally, slant binary tree and sort separability criterion were combined to determine the structure of multi-class RVM, and the singular values were regarded as the fault feature vectors of RVM in the identification of fault types of diesel valve clearance. The experimental results showed that the proposed fault diagnosis method can effectively extract the features of diesel valve clearance and identify the diesel valve fault accurately. 相似文献
13.
基于信息融合技术的结构损伤诊断方法 总被引：1，自引：0，他引：1
为提高结构损伤识别的准确率,将多源信息融合技术引入到结构损伤诊断中．在介绍多源信息融合技术的基本理论、功能模型、级别分类和数学方法的基础上,将2种或多种结构损伤识别方法提取的损伤特征向量进行特征级融合,建立了基于信息融合的结构损伤诊断方法．在钢筋混凝土板损伤试验中测试其模态信息,利用基于信息融合的结构损伤诊断方法进行裂缝位置识别,并与单独使用模态应变能法和柔度法进行损伤识别的结果进行对比．结果显示基于特征级信息融合的结构损伤诊断方法能够准确识别单一损伤识别方法无法识别的结构损伤,对于多位置损伤识别亦有效果．基于信息融合的结构损伤诊断方法具有良好的损伤敏感性．不同的信息融合算法有不同的适用范围,在实际结构健康监测中,要通过详细分析选择合适的多源信息融合算法． 相似文献
14.
现有大部分融合跟踪算法都使用分类器型跟踪算法,这种算法在目标尺度发生变化时会存在一定误差。虽然已有一些解决方案,但仍不能从根本上解决该问题,而且一般无法估算目标的旋转状态。为此,基于CMT 算法提出一种新的基于点的多传感器融合跟踪算法。在获取目标状态上综合了多传感器信息,并对目标中心使用卡尔曼滤波进行修正,能够跟踪目标并获得目标的尺度及旋转信息。实验结果表明,该算法在常见分辨率下跟踪非旋转目标,重叠率与现有算法相当,在分辨率较高的情况下,在实时性上具有优势。 相似文献
15.
功能核磁共振和弥散张量这2种成像方式能够反应人类大脑不同方面的信息,采用小波变换的方法来对这2种医学图像进行融合可以有效改善抑郁症的识别准确率.首先,利用多尺度小波分解方法把每种类型的图像都转换到频域,以得到各频率的成分参数.其次,对于每个被试,将2种图像的分解参数根据频率各自相加,并且通过小波逆变换重建出融合图像.然后,使用主成分分析方法对融合的数据进行降维并得到图像特征.基于融合后图像的特征,采用留一检验方法最终得到了80.95%的抑郁症识别率.可以看出,该小波融合方法能够对当前抑郁症的诊断识别进行有效的改进. 相似文献
16.
巫生平 《福建工程学院学报》2019,(6):532-538
基于频率的结构损伤识别结果易受外界环境温度的影响,应用具有一定的局限性,为此,引入计量经济学中处理非平稳信息的协整概念来消除温度对识别结果的影响。将结构正常运营状态下采集的数据作为训练样本,计算得到协整余量,再根据统计方法选取协整余量的控制线。监测中若频率的协整余量超过该控制线,即认为结构发生损伤。采用上述方法对某实际悬索桥进行分析,结果表明,所提出方法能有效识别悬索桥主梁、主缆和吊索的损伤,具有较好的工程应用前景。 相似文献
17.
将信息处理技术引用到气固两相流参数检测中,初步探讨了应用数据融合技术及互相关技术进行固相颗粒界面平均速度的检测。采用两种方案确定上、下游传感器渡越时间,包括每对传感器采集的数据先进行互相关分析再进行数据加权融合,以及对所有传感器采集的数据先进行融合处理,再对其进行相关分析。通过对这两种信息处理方案进行仿真研究,得到稳定且正确的仿真结果。 相似文献
18.
MRI and PET images fusion based on human retina model 总被引：1，自引：0，他引：1
DANESHVAR Sabalan GHASSEMIAN Hassan 《浙江大学学报(A卷英文版)》2007,8(10):1624-1632
The diagnostic potential of brain positron emission tomography (PET) imaging is limited by low spatial resolution. For solving this problem we propose a technique for the fusion of PET and MRI images. This fusion is a trade-off between the spectral information extracted from PET images and the spatial information extracted from high spatial resolution MRI. The proposed method can control this trade-off. To achieve this goal, it is necessary to build a multiscale fusion model, based on the retinal cell photoreceptors model. This paper introduces general prospects of this model, and its application in multispectral medical image fusion. Results showed that the proposed method preserves more spectral features with less spatial distortion. Comparing with hue-intensity-saturation (HIS), discrete wavelet transform (DWT), wavelet-based sharpening and wavelet-à trous transform methods, the best spectral and spatial quality is only achieved simultaneously with the proposed feature-based data fusion method. This method does not require resampling images, which is an advantage over the other methods, and can perform in any aspect ratio between the pixels of MRI and PET images. 相似文献
19.
Pablo García Ansola Andrés García Javier de las Morenas Javier García Escribano Francisco Javier Otamendi 《浙江大学学报(A卷英文版)》2011,12(11):849-859
The objective of this work is to provide decision-making processes with an updated/real picture of the mobile resources in
industrial environments through a constant feedback of information. The combination of identification technologies and wireless
sensor networks (WSN) is proposed as a key development to guarantee an accurate and timely supply of online information regarding
the localization and tracking of the mobile wireless devices. This approach uses a cooperative and distributed localization
system, called ZigID, which is a WSN based on a Zigbee network with radio frequency identification (RFID) active tags as end
nodes. The WSN can recover not only the ID information stored at the tags attached to mobile resources, but also any other
useful data captured by specific sensors for acceleration, temperature, humidity and fuel status. This paper also shows the
development of ZigID, including devices and information flows, as well as its implementation in ground handling operations
at the Ciudad Real Central Airport, Spain. 相似文献
20.
针对多传感器目标跟踪问题,研究了一种多传感器异步航迹融合算法。由于不同传感器的采样时间各不相同,关联算法首先利用最小二乘法将局部航迹同步化,然后利用加权关联算法将局部航迹进行关联.仿真结果表明该算法能够较好地解决异步航迹的关联问题,在跟踪四个交叉目标的情况下,关联正确率接近90%. 相似文献