oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 67 )

2018 ( 423 )

2017 ( 383 )

2016 ( 379 )

Custom range...

Search Results: 1 - 10 of 23690 matches for " Na Gao "
All listed articles are free for downloading (OA Articles)
Page 1 /23690
Display every page Item
Uniform Estimate of the Finite-Time Ruin Probability for All Times in a Generalized Compound Renewal Risk Model
Qingwu Gao,Na Jin,Juan Zheng
Advances in Decision Sciences , 2012, DOI: 10.1155/2012/936525
Abstract: We discuss the uniformly asymptotic estimate of the finite-time ruin probability for all times in a generalized compound renewal risk model, where the interarrival times of successive accidents and all the claim sizes caused by an accident are two sequences of random variables following a wide dependence structure. This wide dependence structure allows random variables to be either negatively dependent or positively dependent. 1. Introduction In this section, we will introduce a generalized compound renewal risk model, some common classes of heavy-tailed distributions, and some dependence structures of random variables (r.v.s), respectively. 1.1. Risk Model It is well known that the compound renewal risk model was first introduced by Tang et al. [1], and since then it has been extensively investigated by many researchers, for example, Ale?kevi?ien? et al. [2], Zhang et al. [3], Lin and Shen [4], Yang et al. [5], and the references therein. In the paper, we consider a generalized compound renewal risk model which satisfies the following assumptions. Assumption The interarrival times of successive accidents are nonnegative, identically distributed, but not necessarily independent r.v.s with finite mean . Assumption The claim sizes and their number caused by th accident are and , , respectively, where are nonnegative and identically distributed r.v.s with common distribution and finite mean , and are not necessarily independent r.v.s, but and are mutually independent for all , , while are independent, identically distributed (i.i.d.), and positive integer-valued r.v.s with common distribution and finite mean . Assumption The sequences , , and are mutually independent. Denote the arrival times of the th accident by , , which can form a nonstandard renewal counting process with mean function . Hence the total claim amount at time and the total claim amount up to time are, respectively, and then the insurer’s surplus process is given by where is the initial surplus and is the constant premium rate. The finite-time ruin probability within time is defined as Clearly, the ruin can only arise at the times , , then Let be a nonnegative r.v., the random time ruin probability is In order for the ultimate ruin not to be certain, we assume the safety loading condition holds, namely, In the generalized compound renewal risk model above, if all the sequences , , and are i.i.d. r.v.s, then the model is reduced to the standard compound renewal risk model introduced by Tang et al. [1], if , then the model is the renewal risk model, see Tang [6], Leipus and ?iaulys [7],
On the Generalized Ertel--Rossby Invariant

GAO Shouting,XU Pengcheng,LI Na,

大气科学进展 , 2012,
Abstract: A new invariant called the generalized Ertel--Rossby invariant (GER) was developed in this study. The new invariant is given by the dot product of the generalized vorticity and the generalized velocity. The generalized vorticity is the absolute vorticity minus the cross--product of the gradient of Lagrangian--time integrated temperature and the gradient of entropy. The generalized velocity is the absolute velocity minus the sum of the gradient of Lagrangian--time integrated kinetic potential and the Lagrangian--time integrated temperature multiplied by the gradient of entropy. In addition to the traditional potential vorticity, the GER invariant may provide another useful tool to study the atmospheric dynamic processes for weather phenomena ranging from large scales to small scales.
A Distributed Routing Algorithm with Traffic Prediction in LEO Satellite Networks
Gao Zihe,Guo Qing,Na Zhenyu
Information Technology Journal , 2011,
Abstract: These recent years, Low Earth Orbit (LEO) satellite networks, which have global coverage and short round-trip delays, have been playing an increasingly important role. As fast speed, frequent handover and time-varying topology, to develop specialized and efficient routing algorithm is a huge challenge in LEO satellite networks. A Distributed Routing Algorithm with Traffic Prediction (TPDRA) is proposed in this study. TPDRA solves the linearly inseparable problem of satellite traffic prediction in higher dimensionality space and finds the optimal path for data packets through mobile agents. TPDRA consists of two parts, traffic prediction and routing decision. In traffic prediction module, the upcoming traffic from terrestrial is forecasted using Radial Basis Function neural network. In routing decision module, mobile agents traverse the whole satellite networks and collect the routing information. The final routing decision factor is not only depending on the current state of satellite networks, but also related to the future state of satellite nodes. Simulation shows that, compared with ACO, TPDRA has better transmission delay as well as intensive performance for congestion.
Ageing-Related Features of Hair and Scalp in Chinese Women by Clinical Evaluation Study  [PDF]
Sehyun Kim, Su Na Kim, Susun An, Jae Ho Yeon, Xuemin Wang, Li Li, Wei Lai, Hong Liang, Xinghua Gao, Wei Liu, Won Seok Park, Yongjoo Na
Journal of Cosmetics, Dermatological Sciences and Applications (JCDSA) , 2017, DOI: 10.4236/jcdsa.2017.73023
Abstract: There are previous studies of ageing hair and scalp in Caucasians and some Asians, such as Koreans and Japanese. However, the characteristics of scalp and hair have not yet been studied in Chinese, the largest population in the world, especially in terms of ageing. The purpose of this study is to investigate ageing features in Chinese women’s hair and scalp. Methods: In total, 1343 women in China aged 20 to 65 participated in this research. Hair density and diameter were measured and analysed with Folliscope®. Hair color and scalp conditions such as dandruff and erythema were evaluated through microscopic images. Measuring equipment was also used to detect scalp water content, barrier function and sebum secretion. Results: Hair density decreased gradually with ageing, while hair diameter peaked at 40s. The color of hair became bright with ageing because of gray hair and color fading. The degree of scalp sebum and dandruff was higher at younger ages. Interestingly, scalp erythema became more severe with ageing. Conclusion: This study shows the physical and physiological changes of Chinese womens hair and scalp. Most aging features (hair diameter, scalpsebum contents, dandruff and erythema) were noticeable in their 40s, but hair density began to decline in their 30s. This first study of aging hair and scalp in Chinese women would
On the Upper Bounds of Eigenvalues for a Class of Systems of Ordinary Differential Equations with Higher Order
Gao Jia,Li-Na Huang,Wei Liu
International Journal of Differential Equations , 2011, DOI: 10.1155/2011/712703
Abstract: The estimate of the upper bounds of eigenvalues for a class of systems of ordinary differential equations with higher order is considered by using the calculus theory. Several results about the upper bound inequalities of the (
Fire Image Date Fusion Based on Neural Network
基于神经网络的火灾图像特征融合算法

GAO Na,LI Liang,
高娜
,李良

计算机系统应用 , 2010,
Abstract: Considering the unstability and high erroneous recognition with traditional methods for fire detection, this paper analyzes the characteristics of fire image and the familiar interference light source. Four criteria have been mentioned: the area increases gradually, the centroid changes random, the taper angles and the circularity. Fuzzy neural network(NN) is used in information fusion to distinguish the fire. Experiments show that Fuzzy neural network fire detection algorithm can distinguish the fire flame effectively and improve accuracy.
A monoclinic polymorph of 1,3-bis(2-pyridylaminomethyl)benzene
Li-Na Zhu,Shan Gao,Seik Weng Ng
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536807063878
Abstract: The molecules of the title compound, C18H18N4, are linked by two different N—H...Npyridyl hydrogen bonds into a linear chain.
Existence of solutions for quasilinear parabolic equations at resonance
Gao Jia,Xiao-Juan Zhang,Li-Na Huang
Electronic Journal of Differential Equations , 2013,
Abstract: In this article, we show the existence of nontrivial solutions for a class of quasilinear parabolic differential equations. To obtain the solution in a weighted Sobolev space, we use the Galerkin method, Brouwer's theorem, and a compact Sobolev-type embedding theorem proved by Shapiro.
Concentration-Dependent Inhibitory Effect of Baicalin on the Plasma Protein Binding and Metabolism of Chlorzoxazone, a CYP2E1 Probe Substrate, in Rats In Vitro and In Vivo
Na Gao, Dan Zou, Hai-Ling Qiao
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0053038
Abstract: Some of the components found in herbs may be inhibitors or inducers of cytochrome P450 enzymes, which may therefore result in undesired herb-drug interactions. As a component extracted from Radix Scutellariae, the direct effect of baicalin on cytochrome P450 has not been investigated sufficiently. In this study, we investigated concentration-dependent inhibitory effect of baicalin on the plasma protein binding and metabolism of chlorzoxazone (CZN), a model CYP2E1 probe substrate, in rats in vitro and in vivo. Animal experiment was a randomized, three-period crossover design. Significant changes in pharmacokinetic parameters of CZN such as Cmax, t1/2 and Vd were observed after treatment with baicalin in vivo (P<0.05). Cmax decreased by 25% and 33%, whereas t1/2 increased by 34% and 53%, Vd increased by 37% and 50% in 225 mg/kg and 450 mg/kg baicalin-treated rats, respectively. The AUC and CL of CZN were not affected (P>0.05). Correlation analysis showed that the changes in CZN concentrations and baicalin concentrations were in good correlation (r>0.99). In vitro experiments, baicalin decreased the formation of 6-OH-chlorzoxazone in a concentration-dependent manner and exhibited a competitive inhibition in rat liver microsomes, with a Ki value of 145.8 μM. The values of Cmax/Ki were 20 and 39 after treatment with baicalin (225 and 450 mg/kg), respectively. Protein binding experiments in vivo showed that the plasma free-fraction (fu) of CZN increased 2.6-fold immediately after baicalin treatment (450 mg/kg) and in vitro showed that baicalin (125–2500 mg/L) increased the unbound CZN from 1.63% to 3.58%. The results indicate that pharmacokinetic changes in CZN are induced by inhibitory effect of baicalin on the plasma protein binding of CZN and CYP2E1 activity.
The relationship of electron Fermi energy with strong magnetic fields
Qiu He Peng,Zhi Fu Gao,Na Wang
Physics , 2012, DOI: 10.1063/1.4763455
Abstract: In order to depict the quantization of Landau levels, we introduce Dirac $\delta$ function, and gain a concise expression for the electron Fermi energy, $E_{F}(e) \propto B^{1/4}$. The high soft X-ray luminosities of magnetars may be naturally explained by our theory.
Page 1 /23690
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.