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High-Dimensional Nonlinear Envelope Equations and Nonlinear Localized Excitations in Photonic Crystals

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Communications in Theoretical Physics 2006年第1X期46卷 149-154页

作者： HANG Chao HUANG guo-xiang Department of Physics East China Normal University Shanghai 200062 China

We investigate the nonlinear localized structures of optical pulses propagating in a one-dimensional photonic crystal with a quadratic nonlinearity. Using a method of multiple scales we show that the nonlinear evolution of a wave packet, formed by the superposition of short-wavelength excitations, and long-wavelength mean fields, generated by the self-interaction of the wave packet, are governed by a set of coupled high-dimenslonal nonlinear envelope equations, which can be reduced to Davey-Stewartson equations and thus support dromionlike high-dimensional nonlinear excitations in the system.

关键词： photonic crystal dromion

TNF-a-308 polymorphism and risk of digestive system cancers:A meta-analysis

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World Journal of Gastroenterology 2013年第48期19卷 9461-9471页

作者： Xu-Feng guo Jun Wang Shi-jie Yu jia Song Meng-Yao ji Zhuo Cao ji-xiang Zhang jing Wang Wei-guo Dong Department of Gastroenterology Renmin Hospital of Wuhan University

AIM:To evaluate the association between the tumour necrosis factor alpha-308(TNF-a-308)gene polymorphism and the risk of digestive system ***:All eligible case-control studies published up to December 2012 were identified by searching PubMed,Web of Science,Embase and China National Knowledge Internet without language *** risk of digestive system cancers associated with the TNF-a-308 polymorphism was estimated for each study using odds ratio(OR)together with its 95%CI,*** Collaboration RevMan 5.1 was used to perform the analysis.Aχ2-test-based Q statistic test and an I2test were performed to assess the betweenstudy *** the Q test was significant(P50%,the random effects model was used,otherwise the fixed effects model was ***:Fifty-eight studies from fifty-five publications with a total of 9986 cancer patients and 15511 healthy controls were ***,a significant association was found between the TNF-a-308 polymorphism and the risk of digestive system cancers[dominant model:OR=1.23,95%CI:1.09-1.39,(G/A)vs(G/G):OR=1.15,95%CI:1.02-1.28,(A/A)vs(G/G):OR=1.44,95%CI:1.19-1.73,recessive model:OR=1.38,95%CI:1.15-1.66].Furthermore,when the analysis was stratified by ethnicity,similar results were observed in both the Asian and Caucasian populations,except for the dominant model and heterozygote comparisons in the Asian population[dominant model:OR=1.24,95%CI:0.99-1.56,(G/A)vs(G/G):OR=1.09,95%CI:0.96-1.24].When the cancer type subgroups were examined,similar results were detected in gastric and hepatocellular carcinomas;however,no significant association was observed among other digestive system ***:The TNF-a-308 gene polymorphism may be significantly associated with the risk of gastric and hepatocellular carcinomas,but not colorectal,pancreatic,or oesophageal cancer,in the Asian population.

关键词： Tumour necrosis factor alpha rs1800629 Polymorphism Digestive system cancer Meta-analysis Association

Restricted Arc-Connectivity of Harary Digraphs

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Journal of the Operations Research Society of China 2024年第2期12卷 540-547页

作者： Jun-Hao Zhang ji-xiang Meng College of Mathematics and System Science Xinjiang UniversityUrumqi 830046XinJiangChina

The h-restricted arc-connectivity of a digraph is an important parameter to measure fault-tolerance of interconnection *** paper determines that the h-restricted arc-connectivity of the Harary digraph D=G(n;1,2,.:,k)i... 详细信息

关键词： Restricted arc-connectivity λ_(h)(D) Super-λ_(h) λ_(h)-Atom λ_(h)-Superatom

The silicate and carbon-rich models of CoRoT-7b,Kepler-9d and Kepler-10b

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Research in Astronomy and Astrophysics 2012年第6期12卷 678-692页

作者： Yan-xiang Gong ji-Lin Zhou Department of Astronomy ＆ Key Laboratory of Modern Astronomy and Astrophysics inMinistry of Education Nanjing University Nanjing 210093 China College of Physics and Electronic Engineering Taishan University Taian 271021 China

Possible bulk compositions of the super-Earth exoplanets CoRoT-7b, Kepler-9d, and Kepler-10b are investigated by applying a commonly used silicate model and a non-standard carbon model. Their internal structures are deduced using a suitable equation of state for the materials. The degeneracy problems of their compo- sitions can be partly overcome, based on the fact that all three planets are extremely close to their host stars. By analyzing the numerical results, we conclude： 1） the iron core of CoRoT-7b is not more than 27% of its total mass within lc~ mass-radius error bars, so an Earth-like composition is less likely, but its carbon rich model can be com- patible with an Earth-like core/mantle mass fraction; 2） Kepler-10b is more likely to have a Mercury-like composition, with its old age implying that its high iron content may be a result of strong solar wind or giant impact; 3） the transiting-only super-Earth Kepler-9d is also discussed. Combining its possible composition with the formation theory, we can place some constraints on its mass and bulk composition.

关键词： planets and satellites: general -- methods: numerical -- planets andsatellites: individual (CoRoT-7b Kepler-9d Kepler- 10b)

Optimal Dividend Strategy in Compound Binomial Model with Bounded Dividend Rates

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Acta Mathematicae Applicatae Sinica 2014年第4期30卷 859-870页

作者： ji-yang TAN xiang-qun YANG School of Mathematics and Computational Science Xiangtan University College of Mathematics and Computer Science Hunan Normal University

We consider the compound binomial model, and assume that dividends are paid to the shareholders according to an admissible strategy with dividend rates bounded by a *** company controls the amount of dividends in order to maximize the cumulative expected discounted dividends prior to ruin. We show that the optimal value function is the unique solution of a discrete HJB equation. Moreover, we obtain some properties of the optimal payment strategy, and offer a simple algorithm for obtaining the optimal strategy. The key of our method is to transform the value function. Numerical examples are presented to illustrate the transformation method.

关键词： compound binomial model optimal dividend strategy transformation

On all-propulsion design of integrated orbit and attitude control for inner-formation gravity field measurement satellite

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Science China(Technological Sciences) 2011年第12期54卷 3233-3242页

作者： ji Li LIU Kun xiang JunHua Institute of Aerospace and Material Engineering National Universitry of Defense Technology Changsha 410073 China

The inner-formation gravity field measurement satellite （IFS） is a novel pure gravitational orbiter. It aims to measure the Earth＇s gravity field with unprecedented accuracy and spatial resolution by means of precise orbit determination （POD） and relative state measurement. One of the key factors determining the measurement level is the outer-satellite control used for keeping the inner-satellite flying in a pure gravitational orbit stably. In this paper the integrated orbit and attitude control of IFS during steady-state phase was investigated using only thrusters. A six degree-of-freedom translational and rotational dynamics model was constructed considering nonlinearity resulted from quaternion expression and coupling induced by community thrusters. A feasible quadratic optimization model was established for the integrated orbit and attitude control using con- strained nonlinear model predictive control （CNMPC） techniques. Simulation experiment demonstrated that the presented CNMPC aigorithm can achieve rapid calculation and overcome the non-convexity of partial constraints. The thruster layout is rational with low thrust consumption, and the mission requirements of IFS are fully satisfied.

关键词： gravity field measurement satellite inner-formation integrated orbit and attitude control model predictive techniques

Study on gene expression patterns and functional pathways of peripheral blood monocytes reveals potential molecular mechanism of surgical treatment for periodontitis

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World Journal of Clinical Cases 2019年第12期7卷 1383-1392页

作者： jin-ji Ma Hong-Mei Liu xiang-Hua Xu Li-Xin guo Qing Lin jinan Stomatological Hospital Gaoxin Branch Jinan 250001 Shandong Province China Department of Endodontics Jinan Stomatological Hospital Jinan 250001 Shandong Province China Department of Stomatology Shandong Provincial Hospital Jinan 250001 Shandong Province China

BACKGROUND Periodontitis is a chronic inflammation of periodontal supporting tissue caused by local factors. Periodontal surgery can change the gene expression of peripheral blood mononuclear cells. However, little is known about the potential mechanism of surgical treatment for periodontitis. AIM To explore the potential molecular mechanism of surgical treatment for periodontitis. METHODS First, based on the expression profiles of genes related to surgical treatment for periodontitis, a set of expression disorder modules related to surgical treatment for periodontitis were obtained by enrichment analysis. Subsequently, based on crosstalk analysis, we proved that there was a significant crosstalk relationship between module 3 and module 5. Finally, based on predictive analysis of multidimensional regulators, we identified a series of regulatory factors, such as endogenous genes, non-coding RNAs (ncRNAs), and transcription factors, which have potential regulatory effects on periodontitis. RESULTS A total of 337 genes related to surgical treatment for periodontitis were obtained, and 3896 genes related to periodontitis were amplified. Eight expression modules of periodontitis were obtained, involving the aggregation of 2672 gene modules. These modules are mainly involved in G-protein coupled receptor signaling pathway, coupled to cyclic nucleotide second messenger, and adenylate cyclasemodulating G-protein coupled receptor signaling pathway. In addition, eight endogenous genes (including EGF, RPS27A, and GNB3) were screened by network connectivity analysis. Finally, based on this set of potential dysfunction modules, 94 transcription factors (including NFKB1, SP1, and STAT3) and 1198 ncRNAs (including MALAT1, CRNDE, and ANCR) were revealed. These core regulators are thought to be involved in the potential molecular mechanism of periodontitis after surgical treatment. CONCLUSION Based on the results of this study, we can show biologists and pharmacists a new idea to re

关键词： Peripheral blood mononuclear cells Gene expression Dysregulation module Potential molecular mechanism Gene expression pattern

Improving the stability of LiNi_(0.80)Co_(0.15)Al_(0.05)O_2 by AlPO_4 nanocoating for lithium-ion batteries

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Science China Chemistry 2017年第9期60卷 1230-1235页

作者： Ran Qi ji-Lei Shi Xu-Dong Zhang Xian-xiang Zeng Ya-Xia Yin jian Xu Li Chen Wei-Gui Fu Yu-guo guo Li-Jun Wan State Key Laboratory of Separation Membranes and Membrane Processes School of Materials Science and EngineeringTt'anjin Polytechnic UniversityTianjin 300071China CAS Research/Education Center for Excellence in Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeo'ing 100190China School of Chemistry and Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

Nickel-rich layered materials,such as LiNi_(0.8)0Co_(0.15)Al_(0.05)O_2(NCA),have been considered as one alternative cathode materials for lithium-ion batteries(LIBs) due to their high capacity and low ***,their poor cycle life and low thermal stability,caused by the electrode/electrolyte side reaction,prohibit their prosperity in practical ***,AlPO4 has been homogeneously coated on the surface of NCA via wet chemical method towards the target of protecting NCA from the attack of *** with the bare NCA,NCA@AlPO_4 electrode delivers high capacity without sacrificing the discharge capacity and excellent cycling *** 150 cycles at 0.5 C between 3.0-4.3 V,the capacity retention of the coated material is 86.9%,much higher than that of bare NCA(66.8%).Furthermore,the thermal stability of cathode is much improved due to the protection of the uniform coating layer on the surface of *** results suggest that AlPO4 coated NCA materials could act as one promising candidate for next-generation LIBs with high energy density in the near future.

关键词： Li-ion batteries cathode materials surface modification AlPO4 coating

Application of Geometric Midline Yield Criterion for Strip Drawing

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Journal of Iron and Steel Research International 2009年第6期16卷 13-16页

作者： WANG Gen-ji DU Hai-jun ZHAO De-wen LIU xiang-hua WANG guo-dong State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

A new linear yield criterion expressed by the geometric midline of error triangle between Tresca and Twin shear stress yield loci on the π-plane in Haigh-Westergaard space was introduced. The criterion was written in terms of the values of principal stress deviator and called GM yield criterion for short. Together with a Cartesian coordinate velocity field instead of the Avitzur＇s, the GM criterion was used to obtain an analytical solution for strip drawing. With a working example of the strip drawing through wedge-shaped die, the results of relative drawing stress calculated by the GM criterion were compared with those calculated by Mises＇ criterion from Avitzur formula. It indicated that the calculated results according to analytical solution were in good agreement with the numerical solution obtained from Avitzur formula.

关键词： GM yield criterion strip drawing analytical solution