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121.
对学术权力的再审视   总被引:2,自引:0,他引:2  
近年来 ,有的学者对学术权力进行了重新界定 ,提出新的看法。本文从新观点提出的依据、专用术语与普通用语的区别、历史的内涵、概念的定义等角度 ,对这些新观点进行了深入的分析 ,说明了新观点存在的误区 ,指出学术权力这个概念并未超出原来的意义  相似文献   
122.
Using capacitance measurement and Mott-Schottky analysis, the semiconducting properties of passive films formed on chromium within the passive potential range under different conditions were investigated. The study reveals a p-type behavior of the passive layers. Two semiconductive parameters, i.e., the acceptor density (NA) and the flatband potential (EFB), which are mainly related to composition and surface charges of the passive films, have been measured. The effect of film formation potential, passivation time, pH and composition of solutions on the parameters are discussed. NA increases either with lowering film formation potentials or with prolonging passivation times. This is attributed to the transformation of a less hydrated oxide film into a more hydrated form. The changes of EFB are discussed as a function of adsorptive anions and pH values of electrolyte solution.  相似文献   
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124.
This paper presents an approach to design robust non‐fragile HL2 ? L static output feedback controller, considering actuator time‐delay and the controller gain variations, and it is applied to design vehicle active suspension. According to suspension design requirements, the H and L2 ? L norms are used, respectively, to reflect ride comfort and time‐domain hard constraints. By employing a delay‐dependent Lyapunov function, existence conditions of delay‐dependent robust non‐fragile static output feedback H controller and L2 ? L controller are derived, respectively, in terms of the feasibility of bilinear matrix inequalities. Then, a new procedure based on LMI optimization and a hybrid algorithm of the particle swarm optimization and differential evolution is used to solve an optimization problem with bilinear matrix inequality constraints. Simulation results show that the designed active suspension system still can guarantee their own performance in spite of the existence of the model uncertainties, the actuator time‐delay and the controller gain variations. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
125.
126.
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.  相似文献   
127.
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.  相似文献   
128.
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.  相似文献   
129.
We introduce a new method of solving C1 Hermite interpolation problems, which makes it possible to use a wider range of PH curves with potentially better shapes. By characterizing PH curves by roots of their hodographs in the complex representation, we introduce PH curves of type K(tc)2n+1+d. Next, we introduce a speed reparametrization. Finally, we show that, for C1 Hermite data, we can use PH curves of type K(tc)2n+1+d or strongly regular PH quintics satisfying the G1 reduction of C1 data, and use these curves to solve the original C1 Hermite interpolation problem.  相似文献   
130.
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.  相似文献   
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