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Search Results: 1 - 10 of 37302 matches for " CHANG Qing "
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Oxidation rate in the preparation of polyferric sulfate coagulant
CHANG Qing,
CHANG
,Qing

环境科学学报(英文版) , 2001,
Abstract: The oxidation rate of ferrous sulfate was investigated in the preparation of polyferric sulfate(PFS) coagulant. It was proved that this reaction is zero order with respect to Fe 2+ , first order with respect to NO\-2(g) and first order with respect to the interface area between gas phase and liquid phase. If the partial pressure of NO\-2(g) in gas phase is increased or the interface area is increased, the time needed to complete the reaction will be decreased.
Progress and Reseach Needs in Flocculation Science
絮凝科学的研究与进展

Chang Qing,
常青

环境科学 , 1994,
Abstract: 概述近年来絮凝领域一些重要研究:设计操作图:快速混合的物理模型、最佳絮凝剂投量的预计、无分子絮凝剂、最佳处理方案的选择等。提出了若干尚需研究的课题,它们分属模型研究、性研究、最佳过程设计及絮凝剂新品种开发诸方面。
Curative effects of Fuzheng Huayu Capsules on hepatic fibrosis and the functional mechanisms: a review
Chang-Qing ZHAO
Zhong Xi Yi Jie He Xue Bao , 2006,
Abstract: Deficiency of Qi (healthy energy) and blood stasis are the basic pathological changes of hepatic fibrosis according to the theories of traditional Chinese medicine. Fuzheng Huayu Capsule, a compound Chinese herbal medicine for hepatic fibrosis, is produced in the light of this pathological mechanism. More than a decade of clinical studies and experimental researches show that this medicine has effects of protecting hepatic cells, relieving liver injury, and controlling the development of hepatic fibrosis. It has definite functional mechanisms on anti-hepatic fibrosis. It is a safe and effective medicine for hepatic fibrosis, and deserves to be well introduced to clinic.
Thinking and practice on research of effective components of traditional Chinese medicine compound prescriptions
Chang-qing Deng
Zhong Xi Yi Jie He Xue Bao , 2010,
Abstract: : By analyzing current research status and considering our own previous research results, we hold that research on active substance of Chinese herbal formula should be focused on the effect of active components according to its functions, thus determining the main effective components of traditional Chinese medicine (TCM) compound prescriptions. Study of compatibility of effective components should be carried out and compound prescriptions composed of effective components should be developed. It is a pivotal way to deepen research on active components of TCM compound prescription by further analyzing the compatibility of effective components and the relationship between functional components and active components by multilink and multitarget methods.
The Optimization and Improvement of MapReduce in Web Data Mining  [PDF]
Jun Qu, Chang-Qing Yin, Shangwei Song
Journal of Software Engineering and Applications (JSEA) , 2015, DOI: 10.4236/jsea.2015.88039
Abstract: Extracting and mining social networks information from massive Web data is of both theoretical and practical significance. However, one of definite features of this task was a large scale data processing, which remained to be a great challenge that would be addressed. MapReduce is a kind of distributed programming model. Just through the implementation of map and reduce those two functions, the distributed tasks can work well. Nevertheless, this model does not directly support heterogeneous datasets processing, while heterogeneous datasets are common in Web. This article proposes a new framework which improves original MapReduce framework into a new one called Map-Reduce-Merge. It adds merge phase that can efficiently solve the problems of heterogeneous data processing. At the same time, some works of optimization and improvement are done based on the features of Web data.
Flocculation Efficiency in Taylor-Couette Flow  [PDF]
Qing Chang, Yuhong Mao, Liyun Zeng, Changquan Yu
Journal of Materials Science and Chemical Engineering (MSCE) , 2016, DOI: 10.4236/msce.2016.41001
Abstract:

Velocity field data were acquired for Taylor-Couette flow in the annulus gap between a rotating inner cylinder and a fixed concentric outer cylinder by particle image velocimetry. The flocculation efficiencies were also obtained in the same Taylor-Couette flow under the conditions corresponding to the velocity field measurement. It was shown that the flocculation efficiencies reach the maximum values due to the closed vortices in WVF and their contraction and expansion with time, but out of WVF range, the comparatively low flocculation efficiencies were obtained due to the no-closed vortices connected with each other.

Absorption Cross Section and Decay Rate of Stationary Axisymmetric Einstein-Maxwell Dilaton Axion Black Hole

LIU Chang-Qing,

中国物理快报 , 2010,
Abstract:
Asynchronous Convolutional-Coded Physical-Layer Network Coding
Qing Yang,Soung Chang Liew
Computer Science , 2013,
Abstract: This paper investigates the decoding process of asynchronous convolutional-coded physical-layer network coding (PNC) systems. Specifically, we put forth a layered decoding framework for convolutional-coded PNC consisting of three layers: symbol realignment layer, codeword realignment layer, and joint channel-decoding network coding (Jt-CNC) decoding layer. Our framework can deal with phase asynchrony and symbol arrival-time asynchrony between the signals simultaneously transmitted by multiple sources. A salient feature of this framework is that it can handle both fractional and integral symbol offsets; previously proposed PNC decoding algorithms (e.g., XOR-CD and reduced-state Viterbi algorithms) can only deal with fractional symbol offset. Moreover, the Jt-CNC algorithm, based on belief propagation (BP), is BER-optimal for synchronous PNC and near optimal for asynchronous PNC. Extending beyond convolutional codes, we further generalize the Jt-CNC decoding algorithm for all cyclic codes. Our simulation shows that Jt-CNC outperforms the previously proposed XOR-CD algorithm and reduced-state Viterbi algorithm by 2dB for synchronous PNC. For phase-asynchronous PNC, Jt-CNC is 4dB better than the other two algorithms. Importantly, for real wireless environment testing, we have also implemented our decoding algorithm in a PNC system built on the USRP software radio platform. Our experiment shows that the proposed Jt-CNC decoder works well in practice.
Design and Simulation of a Fully Digitized GNSS Receiver Front-End
Yuan Yu,Qing Chang,Yuan Chen
Discrete Dynamics in Nature and Society , 2011, DOI: 10.1155/2011/329535
Abstract: In the near future, RF front-ends of GNSS receivers may become very complicated when multifrequency signals are available from at least four global navigation systems. Based on the direct RF sampling technique, fully digitized receiver front-ends may solve the problem. In this paper, a direct digitization RF front-end scheme is presented. At first, a simplified sampling rate selection method is adopted to determine the optimal value. Then, the entire spectrum of GNSS signal is directly digitized through RF sampling at a very fast sampling rate. After that, the decimation and filtering network is designed to lower the sampling rate efficiently. It also realizes the digital downconversion of the signal of interest and the separation of narrow band signals from different navigation systems. The scheme can be flexibly implemented in software. Its effectiveness is proved through the experiment using simulated and true signals. 1. Introduction With the development of global navigation satellite system (GNSS) including GPS, GLONASS, GALILEO, and COMPASS, multi-constellation signals will be available in the future. These signals mainly concentrate in 1164~1300?MHz and 1559~1610?MHz (referred as “Band I” and “Band II” below). In order to receive all of the GNSS signals, conventional RF front-end may not fit for future multisystem receivers. From the theory of software radio, A/D needs to be set as close to the antenna as possible, thus a single hardware configuration could operate as multiple receivers simply by changing the software programming [1]. Based on such idea, the direct RF sampling offers several advantages for GNSS RF front-end design. First, it reduces the parts count and eliminates the need to design and fabricate a mixing chip with a specially tailored frequency plan. Second, it simplifies the design of new receivers for the new signals that will become available as GPS gets modernized and as Galileo comes on line. Third, it is possible to make a single RF front-end for multiple frequency bands. This approach to multifrequency GNSS receiver front-end design eliminates the need for multiple front-ends, which reduces the parts count and eliminates some potential sources of inter channel line bias. Therefore, the digitized RF front-end is becoming a hot research area. Although software radio is not a novel concept, most studies on direct RF sampling nowadays are still conducted in labs. Brown and Wolt [2] are the first to report on the use of direct RF sampling for the design of GPS receiver front-ends. They concentrated on a system that used a very
The correlation of flare’s location on solar disc and the sudden increase of total electron content
Donghe Zhang,Zuo Xiao,Qing Chang
Chinese Science Bulletin , 2002, DOI: 10.1360/02tb9017
Abstract: The correlation of flare’s location on solar disc with the value of sudden increase of total electron content is analyzed with flare’s parameters observed by GOES satellite from 1997 to 1999 and total electron content derived from GPS data observed by international GPS Service for Geodynamics. It is found that, besides the flare’s maximum X-ray flux, flare’s location on solar disc has some relation with the value of SITEC during the flare. The ionospheric response to a flare with a smaller maximum X-ray flux and nearer angular distance to the Sun’s central meridian line may be stronger than that of the flare with a larger maximum X-ray flux and far angular distance. To the flares with the same class of maximum X-ray flux, the nearer the angular distance to the Sun’s meridian, the stronger the ionospheric response.
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