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Mobility Prediction and Energy-balance Topology-control Algorithm for Ad hoc Networks
无线自组网基于移动预测和能量均衡的拓扑控制算法研究

CHEN Hui,JU Yong-feng,
陈辉
,巨永锋

计算机科学 , 2013,
Abstract: 为了延长无线Ad hoc网络的生存期,降低节点传输过程中的功率消耗, 提出了一种基于能量均衡和节点运动的分布式拓扑控制算法,它使用能够后衡量节点能量损耗量和当前能量值以及根据节点运行方向和速度来评价当前链路稳定状态的路径权值函数, 根据节点剩余能量的实时变化动态优化网络的拓扑结构。仿真结果表明,算法可以构建具有连通性的网络拓扑结构,与其它算法相比,能够均衡整个无线自组网节点的能量,优化网络吞吐率、端到端时延并显著地延长网络的寿命,从而保证网络长时间的可靠运行。
Adaptive control for class of nonlinear system based on system immersion and invariant approach
基于系统侵入与不变流行的非线性系统自适应控制

FAN Xiao-hong,JU Yong-feng,YAN Mao-de,
樊小红
,巨永锋,闫茂德

计算机应用研究 , 2010,
Abstract: 考虑了一类具有非参数不确定非线性系统的自适应控制问题,基于系统侵入与不变流行概念,选用含有系统状态的参数误差表达式,应用非线性阻尼方法,处理参数估计误差中的不确定项,确保参数估计对外界干扰的鲁棒性。应用滑模积分反推法,确定了系统的控制率,证明了在该控制律的作用下系统平衡点全局渐近稳定。该方法设计过程简单, 参数估计误差具有良好的动态性能,而且避免了积分反推法无自适应调节时出现的系统不稳定问题。仿真结果表明,所设计的控制器对非参数不确定性具有很强的稳定性和鲁棒性。
Exponential attractors for a nonclassical diffusion equation
Yong-Feng Liu,Qiaozhen Ma
Electronic Journal of Differential Equations , 2009,
Abstract: In this article, we prove the existence of exponential attractors for a nonclassical diffusion equation in ${H^{2}(Omega)}cap{H}^{1}_{0}(Omega)$ when the space dimension is less than 4.
Afterglow from GRB 070610/Swift J195509.6+261406: an explanation using the fireball model
Kong SiWei,Huang Yong-Feng
Physics , 2009,
Abstract: GRB 070610, which is also named Swift J195509.6+261406, is a peculiar Galactic transient with significant variability on short timescales in both X-ray and optical light curves. One possible explanation is that GRB 070610/Swift J195509.6 + 261406 is a soft gamma-ray repeater (SGR) in our Galaxy. Here we use the fireball model which is usually recognized as the standard model of gamma-ray burst (GRB) afterglows, and the energy injection hypothesis to interpret the X-ray and optical afterglow light curves of GRB 070610/Swift J195509.6 + 261406. It is found that the model is generally consistent with observations.
Strange stars: Can their crust reach the neutron drip density?
Hai Fu,Yong-Feng Huang
Physics , 2003, DOI: 10.1088/1009-9271/3/6/535
Abstract: Electrostatic potential of electrons near the surface of static strange stars at zero temperature is studied within the frame of the MIT bag model. We find that for QCD parameters within rather wide ranges, and if the nuclear crust on the strange star is at a density leading to neutron drip, the electrostatic potential is insufficient to establish an outwardly directed electric field, which is crucial for the survival of such crusts. If a minimum gap width of 200 fm is called in for a more stringent constraint, our calculations completely rule out the possibility of such crusts' presence on strange stars. Therefore, our results prefer against the existence of neutron-drip crust in nature.
Hypoxia-inducible factor-1 alpha, in association with inflammation, angiogenesis and MYC, is a critical prognostic factor in patients with HCC after surgery
Chen-Xin Dai, Qiang Gao, Shuang-Jian Qiu, Min-Jie Ju, Ming-Yan Cai, Yong-Feng Xu, Jian Zhou, Bo-Heng Zhang, Jia Fan
BMC Cancer , 2009, DOI: 10.1186/1471-2407-9-418
Abstract: In a random series of 110 HCC patients, the mRNA of HIF-1alpha, inflammation related factors (COX-2, MMP7 and MMP9), angiogenesis related factors (VEGF and PDGFRA) and MYC in tumor tissue were detected by real-time RT-PCR and HIF-1alpha protein was assessed by immunohistochemistry. The correlations between HIF-1alpha mRNA and the factors mentioned previously, the relationship between HIF-1alpha and clinicopathologic features, and the prognostic value were analyzed.The expression of both HIF-1alpha mRNA and protein in HCC were independent prognostic factors for overall survival (OS) (P = 0.012 and P = 0.021, respectively) and disease-free survival (DFS) (P = 0.004 and P = 0.007, respectively) as well. Besides, the high expression of HIF-1alpha mRNA and protein proposed an advanced BCLC stage and more incidence of vascular invasion. The mRNA of HIF-1alpha had significantly positive correlations to that of COX-2, PDGFRA, MMP7, MMP9, MYC, except VEGF. In addition to HIF-1alpha, COX-2 and PDGFRA were also independent prognosticators for OS (P = 0.004 and P = 0.010, respectively) and DFS (P = 0.010 and P = 0.038, respectively).HIF-1alpha in HCC plays an important role in predicting patient outcome. It may influence HCC biological behaviors and affect the tumor inflammation, angiogenesis and act in concert with the oncogene MYC. Attaching importance to HIF-1alpha in HCC may improve the prognostic and therapeutic technique.HEPATOCELLULAR carcinoma (HCC) is the sixth most common cancer and the third most common cause of death from cancer worldwide, with increasing incidence in western countries [1]. Surgical resection provides an opportunity for cure, but the outcome remains dismal due to frequent tumor recurrence. Recently, better appreciations of the role that tumor microenvironment plays in tumor progression have bring a paradigm shift in developing strategies for cancer management. As a consequence, renewed emphasis has been placed on key features of the tumor microenvir
Stochastic resonance in a time-delayed asymmetric bistable system with mixed periodic signal

Guo Yong-Feng,Xu Wei,Wang Liang,

中国物理 B , 2010,
Abstract: This paper studies the phenomenon of stochastic resonance in an asymmetric bistable system with time-delayed feedback and mixed periodic signal by using the theory of signal-to-noise ratio in the adiabatic limit. A general approximate Fokker--Planck equation and the expression of the signal-to-noise ratio are derived through the small time delay approximation at both fundamental harmonics and mixed harmonics. The effects of the additive noise intensity $Q$, multiplicative noise intensity $D$, static asymmetry $r$ and delay time $\tau$ on the signal-to-noise ratio are discussed. It is found that the higher mixed harmonics and the static asymmetry $r$ can restrain stochastic resonance, and the delay time $\tau $ can enhance stochastic resonance. Moreover, the longer the delay time $\tau $ is, the larger the additive noise intensity $Q$ and the multiplicative noise intensity $D$ are, when the stochastic resonance appears.
(Z)-1-[(3-Cyanophenyl)iminiomethyl]-2-naphtholate
Yong-Feng Zhao,Jin-Ping Xiong,Yu Zuo
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809020224
Abstract: The title compound, C18H12N2O, crystallizes in a zwitterionic form. The dihedral angle between the planes of the benzene ring and naphthalene ring system is 13.95 (5)°. An intramolecular N—H...O interaction results in the formation of a planar six-membered ring, which is oriented at dihedral angles of 13.50 (4) and 4.49 (4)° with respect to the benzene ring and naphthalene ring system, respectively. In the crystal structure, intermolecular C—H...O and C—H...N interactions link the molecules into a two-dimensional network. π–π contacts between the naphthalene systems [centroid–centroid distance = 3.974 (1) ] may further stabilize the structure.
3-[(3,5-Di-tert-butyl-2-hydroxybenzylidene)methyleneamino]benzonitrile
Yong-Feng Zhao,Jin-Ping Xiong,Yu Zuo
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809014809
Abstract: The molecule of the title compound, C22H26N2O, displays a trans configuration with respect to the C=N double bond. The dihedral angle between the planes of the two aromatic rings is 26.30 (15)°. There is a strong intramolecular O—H...N hydrogen bond between the imine and hydroxyl groups.
N-Cyclohexyl-2-(5-methoxy-1H-indol-3-yl)-2-oxoacetamide
Jing Liu,Yong-Feng Liu,Shi Zhang,Ying Gao
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536810054656
Abstract: In the title compound, C17H20N2O3, the cyclohexane ring adopts a chair conformation. In the crystal, intermolecular N—H...O hydrogen bonds link the molecules into layers parallel to the ac plane.
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