High-speed train navigation system based on multi-sensor data fusion and map matching algorithm

Navigation system for high-speed trains is necessary for increased operational safety and efficiency, new services for customers, and low maintenance cost. This paper proposes a high accuracy navigation system for high-speed trains based on a sensor fusion algorithm, with non-holonomic constraints, for multiple sensors, such as accelerometers, gyroscopes, tachometers, Doppler radar, differential GPS, and RFID, and a map matching algorithm. In the proposed system, we consider the federated Kalman filter for sensor fusion, where local filters utilize filter models developed for various sensor types. Especially, the local Kalman filter for RFID positioning, that is detected at irregular time intervals due to the varying train speed and RFID tag spacing, is developed to maintain high performance during GPS outage. In addition, an orthogonal projection map matching algorithm is developed to improve the performance of the proposed system. The performance of the proposed system is demonstrated with numerous simulations for a high-speed train in Korea. The simulation results are analyzed with respect to the existence of tunnel, RFID deployment spacing, RFID location uncertainty, and DGPS error.     

基于拉普拉斯分值和超球支持向量机的轴承故障诊断方法设计

针对轴承振动信号中的故障信息往往很微弱,同时振动样本数据分布不平衡即故障样本占总样本数的比例低,从而导致故障诊断模型训练不精确而影响诊断精度的问题,提出了一种基于拉普拉斯分值和超球大间隔支持向量机的故障诊断方法;首先,采用有标签的训练样本数据和拉普拉斯分值法提取原始振动信号中的微弱故障信息,并降低其数据维数,从而得到用于故障诊断的特征向量,然后设计了一种改进的超球大间隔支持向量机的故障诊断模型,通过最小化超球体积和最大化超球边界和故障样本之间的间隔来实现故障诊断,以解决样本的不均衡问题,最终通过将测试样本数据代入决策方程并通过投票机制确定其故障类别;在Matlab环境下对轴承故障诊断进行实验,实验结果证明了文中方法能有效解决样本的不均衡情况下的故障诊断,且相对其它方法,具有诊断精度高和收敛速度快的优点.     

Automated classification of touching or overlapping M-FISH chromosomes by region fusion and homolog pairing

Automated separation and classification of touching or overlapping chromosomes in a metaphase image is a critical step in computer-aided chromosome analysis. The advent of the multiplex fluorescence in situ hybridization (M-FISH) technology enables multi-spectral chromosome image with rich spectral information and DAPI image with abundant texture information. This paper presents a fusion classification scheme to improve the segmentation of overlapping and touching chromosomes. First, the texture and spectral information is fused to partition the chromosome cluster into a series of homologous regions. Then a graph-theoretical classification and pairing method is proposed to resolve any remaining ambiguity of the aforementioned separation process. Experiment results demonstrate that the proposed method outperforms conventional multi-spectral classification methods in touching and overlapping chromosome separation.     

Interpersonal perception in bulletin board systems among Chinese Internet users

A study investigating the accuracy of interpersonal perception in Internet Bulletin Board Systems (BBS) and the variables that affect the accuracy were conducted in two phases: in the phase one, 58 participants were selected from the BBS which was built on the Internet in advance. During the phase two, participants were requested to complete the Myers–Briggs Type Indicator (MBTI) to assess their personalities, and to choose another member in the BBS as their “target”. The assessment packets were then administered to the participants in the following order: the demographic and Internet use survey, the MBTI used by the judge to assess their target’s personality, and the relationship survey between judge and target. The results showed that 76.7% participants made the correct judgment on two to three out of four dimensions of the personality type. The correlation analysis indicated that the variables affected the accuracy were from four aspects: judge, target, relationship and similarity. The binary logistic regression analysis showed that the target’s personality, the judge’s education level, the similarity between them, the stereotypes and projection played important roles on the accuracy. Possibilities for future research on this issue are also briefly discussed.     

坐标图纸记录曲线矢量化的分段插值算法

针对坐标图纸记录曲线矢量化,提出了一种基于灰度积分投影的分段线性插值算法。这种方法是将记录曲线沿时间轴划分为若干个段,然后用灰度积分投影法选取插值节点,应用分段线性插值算法拟合记录曲线的函数。方法可以应用于纸质观测记录数字化中,是拯救、开发、利用历史资料的新技术。     

利用POMDP模型来增强分布式系统的生存性

针对分布式系统存在的状态信息不完全问题,引入部分可观察的马尔可夫决策过程(POMDP)模型到生存控制系统中.在该控制系统的构造过程中,结合前瞻的思想,提出一种简易、有效的搜索算法(NSL算法)来作出决策,从而在一定程度上弥补了现有生存控制系统的不足,提高了分布式系统的可生存性.     

定量构效关系研究中分子描述符的相关性

分子描述符的计算是定量构效关系(QSAR)研究的基础,也是化学计量学研究的重要内容,在药物化学、环境科学等领域应用广泛。目前可计算的各种分子描述符已超过4 000种,如何选择合适的分子描述符,成为QSAR研究中首先要做的事。本文首先综述了分子描述符的研究进展,然后随机选择10 000余个化合物,利用Cerius2、Sybyl、Dragon软件计算1 600多种分子描述符,最后,采用相关分析和聚类分析研究各描述符之间的关系,相关分析表明,各类分子描述符之间存在较强的线性关系,这种关系通过聚类分析可以直观体现。     

基于办公网络在线实验系统的实现

虚拟仪器技术的发展及应用,使远程实验办公成为可能。本文研究了基于办公网络的MatLab在线实验系统组建的多种技术方案,系统设计采用了Active X组件,COM组件等混合编程技术,服务器采用.NET框架、SQL数据库技术和网页制作技术,使先进的实验资源为办公网络中的所有用户所利用,满足办公环境下在线实验的需求。     

A preliminary attempt to use radiomic features in the diagnosis of extra-articular long head biceps tendinitis

Magnetic Resonance Materials in Physics, Biology and Medicine - This study aims to present a radiomic application in diagnosing the long head of biceps (LHB) tendinitis. Moreover, we evaluated...     

Soft Robotic-Adapted Multimodal Sensors Derived from Entirely Intrinsic Self-Healing and Stretchable Cross-Linked Networks

Flexible sensing technologies that play a pivotal role in endowing robots with detection capabilities and monitoring their motions are impulsively desired for intelligent robotics systems. However, integrating and constructing reliable and sustainable flexible sensors with multifunctionality for robots remains an everlasting challenge. Herein, an entirely intrinsic self-healing, stretchable, and attachable multimodal sensor is developed that can be conformally integrated with soft robots to identify diverse signals. The dynamic bonds cross-linked networks including the insulating polymer and conductive hydrogel with good comprehensive performances are designed to fabricate the sensor with prolonged lifespan and improved reliability. Benefiting from the self-adhesiveness of the hydrogel, strong interfacial bonding can be formed on various surfaces, which promotes the conformable integration of the sensor with robots. Due to the ionic transportation mechanism, the sensor can detect strain and temperature based on piezoresistive and thermoresistive effect, respectively. Moreover, the sensor can work in triboelectric mode to achieve self-powered sensing. Various information can be identified from the electrical signals generated by the sensor, including hand gestures, soft robot crawling motions, a message of code, the temperature of objects, and the type of materials, holding great promise in the fields of environmental detection, wearable devices, human-machine interfacing, and robotics.