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A Quasi-Newton Population Migration Algorithm for Solving Systems of Nonlinear Equations
Hongxia Liu,Yongquan Zhou,Yongmei Li
Journal of Computers , 2011, DOI: 10.4304/jcp.6.1.36-42

Abstract: In this paper, the problem on solving nonlinear equations is transformed into that of function optimization. A new Quasi-Newton Population Migration Algorithm (QPMA) is proposed via combination of population migration algorithm and Quasi-Newton method. The algorithm has the advantages of the Population Migration Algorithm (PMA) such as region search in a certain extent and avoid getting into the local optimum and the Quasi-Newton method such as Quasi-Newton’s local strong searching. Finally, the numerical experiments result show that this algorithm can find the rapid and effective interval solution and the probability of success is higher.

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A Novel Method for Extracting Information from Web Pages with Multiple Presentation Templates
Qingzhong Li,Yanhui Ding,An Feng,Yongquan Dong
Journal of Software , 2010, DOI: 10.4304/jsw.5.5.506-513

Abstract: Web information extraction is the key part of web data integration. With the need of e-commerce website and the development of web design, web pages with multiple presentation templates arise. The current web information extraction systems are usually based on single presentation template, so web pages with multiple presentation templates can’t be extracted efficiently. This paper focuses on the extraction problem about web pages with multiple presentation templates. Four different kinds of this problem have been considered, and a novel method based on path entropy, presentation regularity and ontology knowledge is presented. The experiment indicates that this method is very promising and it achieves excellent recall and precision.

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On the Feasibility of Distributed Kernel Regression for Big Data
Chen Xu,Yongquan Zhang,Runze Li
Statistics , 2015,

Abstract: In modern scientific research, massive datasets with huge numbers of observations are frequently encountered. To facilitate the computational process, a divide-and-conquer scheme is often used for the analysis of big data. In such a strategy, a full dataset is first split into several manageable segments; the final output is then averaged from the individual outputs of the segments. Despite its popularity in practice, it remains largely unknown that whether such a distributive strategy provides valid theoretical inferences to the original data. In this paper, we address this fundamental issue for the distributed kernel regression (DKR), where the algorithmic feasibility is measured by the generalization performance of the resulting estimator. To justify DKR, a uniform convergence rate is needed for bounding the generalization error over the individual outputs, which brings new and challenging issues in the big data setup. Under mild conditions, we show that, with a proper number of segments, DKR leads to an estimator that is generalization consistent to the unknown regression function. The obtained results justify the method of DKR and shed light on the feasibility of using other distributed algorithms for processing big data. The promising preference of the method is supported by both simulation and real data examples.

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Carbon Nanotubes Based Glucose Needle-type Biosensor
Jinyan Jia,Wenjun Guan,Minghao Sim,Yongquan Li,Hong Li
Sensors , 2008, DOI: 10.3390/s8031712

Abstract: A novel needle-type biosensor based on carbon nanotubes is reported. Thebiosensor was prepared by packing a mixture of multi-wall carbon nanotubes (MWCNTs),graphite powder and glucose oxidase (Gox) freeze-dried powder into a glass capillary of 0.5mm inner diameter. The resulting amperometric biosensor was characterizedelectrochemically using amperometry in the presence of hydrogen peroxide and in thepresence of glucose. The glucose biosensor sensitivity was influenced by the glucoseoxidase concentration within the MWCNTs mixture. The optimized glucose needle-typebiosensor displayed better sensitivity and stability, and a detected range of up to 20 mM.Based on its favorable stability, the needle biosensor was first time used in real-timemonitoring system as a kind of online glucose detector. The decay of current response isless than 10% after 24-hour continuous observation.

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Carbon Nanotubes Based Glucose Needle-type Biosensor
Jinyan Jia,Wenjun Guan,Minghao Sim,Yongquan Li
Sensors , 2008,

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Elevated serum uric acid level as a predictor for cardiovascular and all-cause mortality in Chinese patients with high cardiovascular risk
Elevated serum uric acid level as a predictor for cardiovascu-lar and all-cause mortality in Chinese patients with high cardiovascular risk
Yongquan Wu,Meijing Li,Jue Li,Yingyi Luo,Yan Xing,Dayi Hu,
Yongquan Wu,Meijing Li,Jue Li,Yingyi Luo,Yan Xing,Dayi Hu
老年心脏病学杂志(英文版) , 2008,

Abstract: Objective To assess the predictive value of serum uric acid levels for cardiovascular and all-cause mortality in a large prospective population based study.Methods The study was based on 3648 participants in Shanghai and Beijing,who were inpatients with high cardiovascular(CV) risk at baseLine (2004.7 to 2005.1),and blood was taken.Follow-up for death from cardiovascular disease and any cause was complete until January 1,2006.Results The mean follow-up was 1 years.There were 303 deaths during follow-up,of which 121 were cardiovascular.Crude mortality rates were 8.3 % for all patients,6.8% for female patients (116/1715),and 9.7% (187/1933) for male patients.Among men,patients in the lower and higher uric acid groups had increased cardiac and overall mortality risks compared with patients in the normal uric acid groups.Similar relation was found in women but not statistically significant.After adjusting for other conventional risk factors (age,diabetes,hypertension,diuretic use and smoking),baseline uric acid level was still associated with increased risk for death from cardiovascular disease (P=0.005),or death from all causes (P=0.014) Conclusion Our data suggest that abnormal serum uric acid levels are independently and significantly associated with risk of cardiovascular and all-cause mortality.(J Geriatr Cardiol 2008;5:15-20)

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Normes invariantes et existence de filtrations admissibles
Yongquan Hu
Mathematics , 2007,

Abstract: Let L be a finite extension of Q_p and d a positive integer. A conjecture, due to C. Breuil and P. Schneider, says that the existence of invariant norms on certain locally algebraic representations of GL_{d+1}(L) should be equivalent to the existence of certain (d+1)-dimensional de Rham representations of Gal(\bar{L}/L). We prove the easy direction of this conjecture: the existence of invariant norms implies the existence of admissible filtrations, by generalizing an idea of M.Emerton.

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Sur quelques représentations supersingulières de $GL_2(Q_{p^f})$
Yongquan Hu
Mathematics , 2009,

Abstract: Let p>3 be a prime, f a positive integer and Q_{p^f} the unramified extension of Q_p of degree f. After Breuil and Paskunas, to a generic semi-simple continue modulo p representation of the absolute Galois group of Q_{p^f}, we can associate a parameterized family of smooth admissible modulo p representations of GL_2(Q_{p^f}). In this article, we prove that there are more parameters than those known.

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Diagrammes canoniques et representations modulo $p$ de $\GL_2(F)$
Yongquan Hu
Mathematics , 2009,

Abstract: Let $p$ be a prime number and $F$ a local field with residual characteristic $p$. In this article, to an irreducible smooth representation of $GL_2(F)$ over $\bar{\mathbf{F}}_p$ with central character, we associate canonically a diagram which determines the original representation up to isomorphism. We also determine it in some cases.

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