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This study focused on the measurement and diagnostic analysis of partial discharge in power capacitors operating under prolonged periods of high voltage. An off-line test was conducted on two power capacitors, which were subjected to defect preprocessing before the experiment. The partial discharge test of the terminal to the outer casing was carried out using a 24kV high voltage transformer. The...
In this study' a model selection procedure for varying-coefficient model based on longitudinal data is proposed to distinguish three types of variables: variables not in the model' variables in the model with time-independent coefficients and variables in the model with time-varying coefficients. To identify these three kinds of variables simultaneously' we extend the present variable selection method...
A laser system for a light-pulse atom interferometer typically includes a number of laser sources for cooling and for atom optics to meet different frequency detuning requirements at different stages of a measurement sequence. The number of laser units required makes the achievable minimum size and power of the instrument challenging, especially for space applications. We demonstrate a compact cesium...
Time-delay interferometer (TDI) is well established as an effective technique to mitigate laser phase noises in laser interferometer gravitational wave detection. Just as important in the TDI scheme is the ability to suppress the rf local oscillator noises in the optical heterodyne measurements. We show that the local oscillator noises can be effectively and elegantly cancelled by employing optical...
Whispering gallery mode resonators find key applications in microwave photonic oscillators for aerospace engineering, frequency synthesis, and time-frequency metrology. However, their elastic mechanical deformations induce undesirable shifts for their optical eigenfrequencies, which should ideally be immune to vibrations. We propose a mounting configuration that provides strong immunity against external...
High Speed Air Rotor-Bearing (HSAR) systems have been extensively applied for a variety of mechanical engineering parts, and potential for use in high-rotational speed, high-precision and high stiffness instrumentation. The current study presents a detailed theoretical analysis of bearing performance, in which a hybrid method combing finite difference method (FDM) and differential transformation method...
This paper proposes a novel system for generating 1-D m-scroll, 2-D m×n-grid multi-scroll, 3-D m×n×l-grid multi-scroll chaotic attractors (GMSCAs) via switching piecewise linear (PWL) function. First, a third-order linear system satisfying certain conditions is introduced as the original system. Then, by adding stair function, saturated function series and hysteresis function series to the third-order...
This paper proposes a systematically method for generating high-dimensional grid multi-scroll attractors (GMSAs), including 3-D, 4-D, 5-D and even higher-dimensional GMSAs. Firstly, based on a third-order linear system, higher-order linear systems are constructed by introducing state feedback controllers. Then, switching piecewise linear (PWL) functions, including stair function and saturated series...
Chinese text classification is always challenging, especially when data are high dimensional and sparse. In this paper, we are interested in the way of text representation and dimension reduction in Chinese text classification. First, we introduces a topic model — Latent Dirichlet Allocation(LDA), which is uses LDA model as a dimension reduction method. Second, we choose Support Vector Machine(SVM)...
We describe the development and frequency instability measurements of a highly miniaturized, buffer gas cooled, trapped-ion atomic clock. The clock utilizes the 12.6 GHz hyperfine transition of the 171Yb+ ion. A custom-built 3 cm3 vacuum package containing the ion trap is integrated with other key elements of the atomic frequency standard, including a photo multiplier tube, miniaturized laser sources...
The development of internet technology has made great impacts on our daily lives. Since the world has gone through the changes of industrial economy to knowledge economy and internet knowledge explosion, the centers of enterprise operations have also been switched from real property assets to intangible assets and consumer anticipations. This research was aimed to base on the studies on the relations...
For recent years, attribute-based trust management has become the key factors for enterprises' operational performances. To cope with the trend of internationalization and global competitions, the enhancement of attribute-based trust management has turned into the real estate industry's priority to enhance their competitive advantages. Nowadays, house buyers that are familiar with particular regions...
We report the development of a low-power, miniature Yb-171 ion clock at Sandia National Laboratories. This work is funded by the DARPA micro Position, Navigation, and Timing program under the Integrated Micro Primary Atomic Clock Technology (IMPACT) project. The ultimate goal is to develop a frequency standard that has frequency stability comparable to a commercial Cs beam standard, but with 100 to...
Taking advantage of some of unique optical properties of crystalline materials, we explore use of crystalline whispering gallery mode resonators for laser frequency stabilization, nonlinear frequency conversion, and low threshold UV laser.
This paper presents a Game Platform for intergeneration cultural communication based on Confucius doctrine, engaging text and pictures in the dialog. The initial platform is text based. Enhancements have included picture exchange mechanisms and automatic detection of user emotion, e.g., via a Brain-Computer Interface (BCI.) Pictures are rendered by search engines, as well as retrieved from personal...
Parallel computing model plays a great basic role in advanced computing; Based on researching existing parallel computing models, this paper brings forward a parallel computing model-Layer Forward Net toward Cubic-R architecture, and describes the model's structure, parameter, logic abstractly. Lastly towards typical N-Body problem, this paper designs a parallel algorithm, and analyses its complexity...
We report the observation of second harmonic generations from an x-cut beta barium borate (BBO) disk pumped at 1557 nm. This x-cut geometry will provide a new phase matching condition for nonlinear processes in resonators.
This paper develops a background generation scheme for a color video sequence. We use a temperate background in grayscale for training and a formal background in color for object extraction. Besides, we use current frame, previous frame and previous twentieth frame to achieve a well performance color background to avoid suddenly moving. Several test sequences with difference scenes are used to demonstrate...
We report on whispering gallery mode resonators used as reference cavities for laser frequency stabilization. Differential sensing of orthogonal modes allows active control of the resonator temperature, improving the locked laser's frequency stability.
Web Service is one of implementation modes of distributed systems and is becoming the next generation web-based application. As the amount of Web services is increasing, service experience problem is emerging. After Web services are implemented and published, service providers do not know their running effect and user satisfactory degree. So in order to provide better services and improve user experience...
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