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Search Results: 1 - 10 of 127077 matches for " LI HongGuang "
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An Approach to Dynamic Asymptotic Estimation for Hurst Index of Network Traffic  [PDF]
Xiaoyan MA, Hongguang LI
Int'l J. of Communications, Network and System Sciences (IJCNS) , 2010, DOI: 10.4236/ijcns.2010.32023
Abstract: As an important parameter to describe the sudden nature of network traffic, Hurst index typically conducts behaviors of both self-similarity and long-range dependence. With the evolution of network traffic over time, more and more data are generated. Hurst index estimation value changes with it, which is strictly consistent with the asymptotic property of long-range dependence. This paper presents an approach towards dynamic asymptotic estimation for Hurst index. Based on the calculations in terms of the incremental part of time series, the algorithm enjoys a considerable reduction in computational complexity. Moreover, the local sudden nature of network traffic can be readily captured by a series of real-time Hurst index estimation values dynamically. The effectiveness and tractability of the proposed approach are demonstrated through the traffic data from OPNET simulations as well as real network, respectively.
Synthesis and Tribological Properties of Zinc Oxythiomolybdate
Hongguang GAO,Shizhuo LI,Xiaoxia JIANG,

材料科学技术学报 , 1997,
Abstract: With the chemical synthesis of zinc oxythiomolybdate (ZnMoO2S2), its characters were studied by thermal analysis and X-ray diffraction method. The tribological properties of ZnMoO2S2were studied by high-temperature pin on disc tester, the results show that ZnMoO2S2 has good lubricating property from room temperature to 700℃, especially from 100℃ to 300℃, the friction coefficient is about 0.1.
Adaptive Extraction of Principal Colors Using an Improved Self-Growing Network
Yurong Li,Zhengdong Du,Hongguang Fu
Journal of Computers , 2010, DOI: 10.4304/jcp.5.2.202-209
Abstract: This paper aims to solve the two major issues existing in current color quantization algorithms. The first one is to require users to specify the number of representative colors in advance; the other is that it is difficult in choosing the colors to describe accurately the essential details represented by small groups of pixels isolated in the color space. Based on the growing mechanism of the Growing When Required neural network, a novel algorithm is proposed to adaptively extract the prominent colors of an image. A number of criteria are introduced that have an effect on controlling of the number and topology of neurons in the output layer. A global permutation method to rearrange the input sample order is presented based on Linear Pixels Shuffling in order to improve the performance of the network. The experiments show that the proposed method can automatically estimate the number of colors to efficiently represent an original image, meanwhile capable of retaining important isolated colors even when the number of the representative colors is low. It is also shown that the algorithm outperforms the popular ones in terms of color distortion.
3D-QSAR Study on a Series of VEGFR-2 Kinase Inhibitors: 3-Pyrrole Substituted Indolin-2-Ones Compounds
Shunlai Li,Rutao Zhang,Hongguang Du
Journal of Chemistry , 2013, DOI: 10.1155/2013/374804
Abstract: The vascular endothelial growth factor receptor-2 kinases (VEGFR-2) are attractive targets for the development of anticancer agents. Self-organizing molecular field analysis (SOMFA) (a simple three-dimensional quantitative structure-activity relationship (3D-QSAR) method) is used to study the structure-activity correlation of 3-pyrrole substituted indolin-2-ones VEGFR-2 inhibitors. The statistical results, cross-validated (0.5267) and non-cross-validated (0.5623), show a reliable predictive ability. The contributions of shape and electrostatic fields are 42.7% and 57.3%, respectively. Analysis of SOMFA models through shape and electrostatic grids provide useful information for the design and optimization of new 3-pyrrole substituted indolin-2-one based VEGFR-2 inhibitors. 1. Introduction Cancer is the second leading cause of death in the world. Researchers have found that receptor tyrosine kinases (RTKs) play an important role in oncogenic transformation of cells [1]. VEGFR-2 (vascular endothelial growth factor receptor-2), as a member of the family of RTKs, is widely investigated in the pathogenesis of several disorders [2–7]. It is not only widely distributed in the organization of vascular endothelial cells but also distributed in some tumor cells; it plays an important role in the cell signalling of VEGF and tumor proliferation [8]. Recent research has shown that the blockade of VEGFR-2 signalling by small molecular inhibitors to the kinases domain can inhibit the growth of solid tumors [9–12]. Therefore, inhibition of the VEGFR-2 has become an important research direction in the treatment of cancers [13]. In recent years, a number of VEGFR-2 kinase inhibitors have been developed as anticancer agents, including analogues of quinazoline, indolin ketones, pyridazine, and quinoline structures [14–17]. Recent research found that a series of 3-pyrrole substituted indolin-2-one compounds show good inhibitory activity against VEGFR-2, shown in Table 1, including sunitinib (compound 4) which has been recently approved by US FDA for the treatment of gastrointerstinal stromal tumor (GIST) and renal cell carcinoma (RCC). However, there are fewer quantitative structure-activity relationship (2D-QSAR and 3D-QSAR) studies and other molecular modeling works on VEGFR-2 targets [18–23]. Table 1: Structures of 34 compounds and their VEGFR-2 inhibitory activities. The self-organizing molecular field analysis (SOMFA) [24] is a simple 3D-QSAR technique, which has been developed by Robinson et al. The method has similarities to both comparative molecular field analysis
Abundance and Clustering of C IV Absorption Systems in the SCDM, LCDM and CHDM Models
HongGuang BI,Li-Zhi FANG
Physics , 1996, DOI: 10.1086/177536
Abstract: We have developed a method for calculating the two-point correlation function of nonlinearly evolved mass and collapsed halos in the Press-Schechter formalism. The nonlinear gravitational interaction is treated as the sum of various individual spherical top-hat clustering. Because no collapsed halo of mass M can exist in initial regions (or top-hat spheres) of mass less than M, the bias that massive halos have stronger correlation than the background mass can be naturally introduced. We apply this method to derive constraints on popular dark-matter models from the spatial number density and the correlation function of C IV absorption systems in QSO spectra. Considering C IV systems should behosted by collapsed halos, one can obtain an upper limit to the threshold mass of the collapsed halos by requiring their number density to be larger than that of observed C IV systems. On the other hand, in order to explain the observed clustering of C IV systems, a lower limit to the threshold mass will be set for the hosting halos. The cold dark matter model, the Lamda CDM model and the cold-plus-hot dark matter model are tested using the C IV observations.
A modeling approach for fuzzy programming with echelon form membership functions
WEN Bo, LI HongGuang, CHEN XiaoChun
- , 2018, DOI: 10.13543/j.bhxbzr.2018.01.013
Abstract: In order to solve fuzzy mathematical programming with soft constraints,the initial models must first be converted into crisp models.Membership functions are employed to describe the fuzzy right-hand side parameters needed to achieve this conversion.In some cases,echelon form membership functions (EFMFs) are required to depict the actual fuzzy situation.However,due to their discrete properties,fuzzy programming problems with such membership functions cannot be modeled by traditional methods.Motivated by these challenges,this paper introduces a novel absolute value representation modeling approach to formulate fuzzy programming using EFMFs.This approach can translate a discrete model to a continuous one which can then be easily solved.Finally,by means of a numerical example,the effectiveness of our new approach is demonstrated.
Abstract:In order to solve fuzzy mathematical programming with soft constraints,the initial models must first be converted into crisp models.Membership functions are employed to describe the fuzzy right-hand side parameters needed to achieve this conversion.In some cases,echelon form membership functions (EFMFs) are required to depict the actual fuzzy situation.However,due to their discrete properties,fuzzy programming problems with such membership functions cannot be modeled by traditional methods.Motivated by these challenges,this paper introduces a novel absolute value representation modeling approach to formulate fuzzy programming using EFMFs.This approach can translate a discrete model to a continuous one which can then be easily solved.Finally,by means of a numerical example,the effectiveness of our new approach is demonstrated.
Network Sorting Algorithm of Multi-Frequency Signal with Adaptive SNR
Network Sorting Algorithm of Multi-Frequency Signal with Adaptive SNR

Xinyong Yu,Ying Guo,Kunfeng Zhang,Lei Li,Hongguang Li
- , 2018, DOI: 10.15918/j.jbit1004-0579.201827.0207
Abstract: An signal noise ratio (SNR) adaptive sorting algorithm using the time-frequency (TF) sparsity of frequency-hopping (FH) signal is proposed in this paper. Firstly, the Gabor transformation is used as TF transformation in the system and a sorting model is established under undetermined condition; then the SNR adaptive pivot threshold setting method is used to find the TF single source. The mixed matrix is estimated according to the TF matrix of single source. Lastly, signal sorting is realized through improved subspace projection combined with relative power deviation of source. Theoretical analysis and simulation results show that this algorithm has good effectiveness and performance.
An signal noise ratio (SNR) adaptive sorting algorithm using the time-frequency (TF) sparsity of frequency-hopping (FH) signal is proposed in this paper. Firstly, the Gabor transformation is used as TF transformation in the system and a sorting model is established under undetermined condition; then the SNR adaptive pivot threshold setting method is used to find the TF single source. The mixed matrix is estimated according to the TF matrix of single source. Lastly, signal sorting is realized through improved subspace projection combined with relative power deviation of source. Theoretical analysis and simulation results show that this algorithm has good effectiveness and performance.
Phase behavior and properties of salt-free cationic/anionic surfactant mixtures of oleic acid and stearic acid
DianYing Zhao,HongGuang Li,AiXin Song,JingCheng Hao
Chinese Science Bulletin , 2009, DOI: 10.1007/s11434-009-0510-y
Abstract: Cationic base surfactant, tetradecyltrimethylammonium hydroxide (TTAOH), can be obtained through anion exchange from tetradecyltrimethylammonium bromide (TTABr). Salt-free cationic and anionic (catanionic) surfactant mixtures were studied by mixing TTAOH with oleic acid (OA) or stearic acid (SA) in water. The phase behavior of TTAOH/OA/H2O is compared with that of TTAOH/SA/H2O. It was found that the phase behavior of TTAOH/OA/H2O and TTAOH/SA/H2O system differs from each other due to the existence of the unsaturated double carbon bond (C=C) in OA. At fixed total surfactant concentration (25 mg/mL) of TTAOH/OA/H2O system at 25°C, one can observe an isotropic L1 phase, and a L1/Lα two-phase region with increasing OA content. The volume of top turbid Lα phase increases while the bottom phase changes gradually from transparently clear to a bit turbid until a single Lα-phase is reached. Finally at high OA concentration, excess OA is separated from the bulk aqueous solutions. TTAOH/SA/H2O system usually forms white precipitating at 25°C due to the high chain melting temperature of SA. When heated to 60°C, however, the state of samples changes. At fixed total surfactant concentration of 25 mg/mL, an isotropic L1 phase and a milk-white or bluish Lα-phase are observed with increasing SA concentration. Transparent thin layers which are strongly birefringent form at the tops of some samples within the Lα-phase region. Finally, at high SA concentration, excess SA is separated from the bulk aqueous solutions. In addition to phase behavior study, we also measured the conductivity of TTAOH/OA/H2O system at 25°C and TTAOH/SA/H2O system at 60°C, respectively. Surface tension and rheological measurements were also performed on typical samples.
Anthropogenic Chromium Emissions in China from 1990 to 2009
Hongguang Cheng, Tan Zhou, Qian Li, Lu Lu, Chunye Lin
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0087753
Abstract: An inventory of chromium emission into the atmosphere and water from anthropogenic activities in China was compiled for 1990 through to 2009. We estimate that the total emission of chromium to the atmosphere is about 1.92×105t. Coal and oil combustion were the two leading sources of chromium emission to the atmosphere in China, while the contribution of them showed opposite annual growth trend. In total, nearly 1.34×104t of chromium was discharged to water, mainly from six industrial categories in 20 years. Among them, the metal fabrication industry and the leather tanning sector were the dominant sources of chromium emissions, accounting for approximately 68.0% and 20.0% of the total emissions and representing increases of15.6% and 10.3% annually, respectively. The spatial trends of Cr emissions show significant variation based on emissions from 2005 to 2009. The emission to the atmosphere was heaviest in Hebei, Shandong, Guangdong, Zhejiang and Shanxi, whose annual emissions reached more than 1000t for the high level of coal and oil consumption. In terms of emission to water, the largest contributors were Guangdong, Jiangsu, Shandong and Zhejiang, where most of the leather production and metal manufacturing occur and these four regions accounted for nearly 47.4% of the total emission to water.
A Prescribed Chinese Herbal Medicine Improves Glucose Profile and Ameliorates Oxidative Stress in Goto-Kakisaki Rats Fed with High Fat Diet
Lin Wu, Xiang Li, Hongguang Zhu, Ping Xu, Xin Gao
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0060262
Abstract: Oxidative stress (OS) plays a role in hyperglycemia induced islet β cell dysfunction, however, studies on classic anti-oxidants didn’t show positive results in treating diabetes. We previously demonstrated that the prescribed Chinese herbal medicine preparation “Qing Huo Yi Hao” (QHYH) improved endothelial function in type 2 diabetic patients. QHYH protected endothelial cells from high glucose-induced damages by scavenging superoxide anion and reducing production of reactive oxygen species. Its active component protected C2C12 myotubes against palmitate-induced oxidative damage and mitochondrial dysfunction. In the present study, we investigated whether QHYH protected islet β cell function exacerbated by high fat diet (HFD) in hyperglycemic GK rats. 4-week-old male rats were randomly divided into high HFD feeding group (n = 20) and chow diet feeding group (n = 10). Each gram of HFD contained 4.8 kcal of energy, 52% of which from fat. Rats on HFD were further divided into 2 groups given either QHYH (3 ml/Kg/d) or saline through gastric tube. After intervention, serum glucose concentrations were monitored; IPGTTs were performed without anesthesia on 5 fasting rats randomly chosen from each group on week 4 and 16. Serum malondialdehyde (MDA) concentrations and activities of serum antioxidant enzymes were measured on week 4 and 16. Islet β cell mass and OS marker staining was done by immunohistochemistry on week 16. QHYH prevented the exacerbation of hyperglycemia in HFD feeding GK rats for 12 weeks. On week 16, it improved the exacerbated glucose tolerance and prevented the further loss of islet β cell mass induced by HFD. QHYH markedly decreased serum MDA concentration, increased serum catalase (CAT) and SOD activities on week 4. However, no differences of serum glucose concentration or OS were observed on week 16. We concluded that QHYH decreased hyperglycemia exacerbated by HFD in GK rats by improving β cell function partly via its antioxidant effect.
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