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匹配条件： “WANG Zhen-Xing” ，找到相关结果约165803条。
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$a_1(1260), a_1(1420)$ and the production in heavy meson decays
Wei Wang,Zhen-Xing Zhao
Physics , 2015,

Abstract: The $a_1(1420)$ with $I^G(J^{PC})= 1^-(1^{++})$ observed in the $\pi^+ f_0(980)$ final state in the $\pi^-p\to \pi^+\pi^-\pi^- p$ process by the COMPASS collaboration seems unlikely to be an ordinary $\bar qq$ mesonic state. Available theoretical explanations include tetraquark or rescattering effects due to $a_1(1260)$ decays. If the $a_1(1420)$ were induced by the rescattering, its production rates are completely determined by those of the $a_1(1260)$. In this work, we propose to explore the ratios of branching fractions of heavy meson weak decays into the $a_1(1420)$ and $a_1(1260)$, and testing the universality of these ratios would be a straightforward way to validate/invalidate the rescattering explanation. The decay modes include in the charm sector the $D^0\to a_1^-\ell^+\nu$ and $D^0\to \pi^\pm a_1^\mp$, and in the bottom sector $\overline B^0\to a_1^+ \ell^- \bar\nu$, $B\to D a_1, \pi^\pm a_1^\mp$, $B_c\to J/\psi a_1$ and $\Lambda_b\to \Lambda_c a_1$. We calculate the branching ratios for various decay modes into the $a_1(1260)$. The numerical results indicate that there is a promising prospect to study these decays on experiments including BES-III, LHCb, Babar, Belle and CLEO-c, the forthcoming Super-KEKB factory and the under-design Circular Electron-Positron Collider. Experimental analyses in future will lead to a deeper understanding of the nature of the $a_1(1420)$.

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Regular reduction of controlled Hamiltonian system with symplectic structure and symmetry
Jerrold E. Marsden,Hong Wang,Zhen-Xing Zhang
Mathematics , 2012,

Abstract: In this paper, our goal is to study the regular reduction theory of regular controlled Hamiltonian (RCH) systems with symplectic structure and symmetry, and this reduction is an extension of regular symplectic reduction theory of Hamiltonian systems under regular controlled Hamiltonian equivalence conditions. Thus, in order to describe uniformly RCH systems defined on a cotangent bundle and on the regular reduced spaces, we first define a kind of RCH systems on a symplectic fiber bundle. Then introduce regular point and regular orbit reducible RCH systems with symmetry by using momentum map and the associated reduced symplectic forms. Moreover, we give regular point and regular orbit reduction theorems for RCH systems to explain the relationships between RpCH-equivalence, RoCH-equivalence for reducible RCH systems with symmetry and RCH-equivalence for associated reduced RCH systems. Finally, as an application we regard rigid body and heavy top as well as them with internal rotors as the regular point reducible RCH systems on the rotation group $\textmd{SO}(3)$ and on the Euclidean group $\textmd{SE}(3)$,as well as on their generalizations, respectively, and discuss their RCH-equivalence. We also describe the RCH system and RCH-equivalence from the viewpoint of port Hamiltonian system with a symplectic structure.

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Tracking of group targets using multiple models GGIW
Guo-Ping Hu,Yun Wang,Zhen-Xing Li
- , 2018, DOI: 10.1177/0954410016684359

Abstract: Gamma Gaussian inverse Wishart probability hypothesis density (GGIW-PHD) filter algorithm is always used for tracking group targets with unknown number and variable measurement rates in the presence of cluttered measurements and missing detections. Aiming at the defect that the tracking error of GGIW-PHD filter algorithm will increase greatly in the maneuvering stage, a multiple model GGIW-PHD (MM-GGIW-PHD) algorithm is proposed in this paper based on the best-fitting Gaussian approximation and strong tracking filter. Firstly, on the basis of measurement set partition, the best-fitting Gaussian approximation method is proposed to implement the fusion of multiple models in the PHD predict stage. And a fading factor of strong tracking filter is proposed to correct the predicted covariance matrix of the GGIW component. Then, the estimation of kinematic state and extension state are deduced in the frame of multiple models. The probability of different tracking models is updated by the modified likelihood functions. The simulation results show that the MM-GGIW-PHD algorithm based on best-fitting Gaussian approximation and strong tracking filter can decrease the tracking error of group targets in the maneuvering stage and treated with the combination/spawning of group effectively

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Crust structure beneath Tengchong-Lincang region, Yunnan province, revealed by transform function
用转换函数方法研究腾冲—临沧地区地壳结构
GAO Xing,GUO Zhi,WANG Wei-Min,YAO Zhen-Xing,
高星
地球物理学报 , 2008,

Abstract: 根据流动数字地震台网提供的三分量地震波形记录资料,应用转换函数及快速模拟退火算法对腾冲-临沧地区30个地震台站下的地壳横波速度结构进行了反演.反演结果说明,研究区壳幔边界清晰、莫霍界面附近速度跳跃明显,由此得出该区地壳厚度在40 km左右、并具有从南向北增厚趋势.一个普遍的现象是,在腾冲-宝山地块下地壳存在明显的低速带,低速带的厚度在10～20 km间.研究结果进一步表明各台站下方上地幔速度结构复杂.这些结果为探讨青藏高原东南缘下地壳的侧向黏性流动、碰撞板块边界处壳幔物质交换等均提供了重要的地球物理证据,为探讨印-藏汇聚过程中青藏高原东构造结岩石圈变形、高原隆升及其深部动力学有一定理论意义.

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DIELECTRIC RELAXATION BEHAVIOR OF CERAMICS IN THE Pb(Zn1/3Nb2/3)O3-BaTiO3-PbTiO3 SYSTEM

YUE ZHEN-XING,WANG XIAO-LI,ZHANG LIANG-YING,YAO XI,

中国物理 B , 1997,

Abstract: The dielectric properties of ceramics in Pb(Zn1/3Nb2/3)O3-BaTiO3-PbTiO3 system were characterized using dielectric-temperature spectra. A spontaneous (zero field) relaxor-normal ferroelectric tran sition was observed for tetragonal rich compositions. A significant hysteresis effect accompanied by this transition, similar to first-order phase transition of normal ferroelectrics. This behavior was different from that of other relaxors, in which such transitions occurred only under a biased dc field. This observation was explained in terms of a thermally driven transformation from an ensemble of polar microregions to normal long-range ferroelectric state (micro-macro domain transition), which was attributed to the internal field resulting from the tetragonal strain.

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Denitrification Using Polylactic Acid as Solid Carbon Source
利用聚乳酸作为反硝化固体碳源的研究
FAN Zhen-xing,WANG Jian-long,
范振兴,王建龙
环境科学 , 2009,

Abstract: 利用聚乳酸(PLA)颗粒作为反硝化的固体碳源和生物膜载体,考察了聚乳酸作为反硝化碳源的可行性和温度对聚乳酸颗粒反硝化脱氮性能的影响,并对聚乳酸颗粒表面进行了红外光谱分析和扫描电镜观察.结果表明,PLA颗粒作为反硝化固体碳源和生物膜载体进行反硝化脱氮,接种和驯化时间较长.在30℃,硝酸盐氮初始浓度为50 mg/L时,PLA的平均反硝化速率为2.6×10-3mg/(g.h),13 h内硝酸氮可以完全去除.温度对反硝化速率影响很大,在30~40℃之间反硝化速率较高,一旦偏离适宜温度,反硝化速率降低很快.对PLA颗粒表面的红外光谱分析和扫描电镜观察证实了PLA作为反硝化固体碳源的可行性.PLA颗粒表面的生物膜扫描电镜观察发现生物膜比较薄,以球菌为主.

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ND-based DoS attacks and countermeasures
基于ND的DoS攻击及其对策*
LI Shuo,WANG Zhen-xing,YANG Xi,
李硕,王振兴,杨希
计算机应用研究 , 2007,

Abstract: 通过深入分析邻居发现协议运行机制,指出了链路可信这个默认前提是导致ND(neighbor discovery)存在安全缺陷的根本原因;随后具体分析了基于ND安全缺陷各种DoS攻击方法,并对ND的安全防护进行了阐述,为进一步研究安全ND奠定了基础.

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Web Instant Messaging System Based on Server Push Technology and php
基于php 和服务器推技术的Web 即时聊天系统
WANG Zhen-Xing,HUANG Jing,
王振兴,黄静
计算机系统应用 , 2012,

Abstract:

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The study on the relationships of elastic properties of rock physics
岩石物理弹性参数规律研究
LI Wei-Xin,SHI Ge,WANG Hong,YAO Zhen-Xing,
李维新
地球物理学进展 , 2007,

Abstract: The relationships among elastic properties of rock physics have been discussed based on in situ measurement data with different pore fluid types and saturation in the area of LiaoDong Gulf,combined with clay content and porosity of rocks.Comparing measurement data with predicted data by effective-fluid model and patchy-saturated model,such as compressional and shear velocity,the results show that effective-fluid model is applicable to rocks with high porosity and high permeability well,while patchy-saturated model is more applicable to rocks with low porosity and low permeability.These conclusions are important to reservoir and pore fluid predictions from seismic data.

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Thermoregulatory and thermal dependence of resting metabolic rates in the Chinese crocodile lizard Shinisaurus crocodilurus in the Luokeng Nature Reserve, Guangdong
WANG Zhen-Xing,WU Zheng-Jun,YU Hai,HUANG Cheng-Ming
Acta Zoologica Sinica , 2008,

Abstract: To explore the thermoregulatory and thermal dependence of resting metabolic rates (RMR) in the Chinese crocodile lizard Shinisaurus crocodilurus, we measured the active body temperature, the diel variation in body temperature, the average daily body temperatures, the ambient temperature and the resting metabolic rate in the wild and under controlled laboratory conditions. Results showed that in the wild, active body temperature (Tb) was higher than substrate temperature (Tc) and air temperature (Td) and was positively correlated with the latter two (Tb = 11.65 + 0.47Tc , r2 = 0.34, F1, 75= 39.11, P < 0.0001; Tb = 11.61 + 0.46Td, r2 = 0.56, F1, 75= 96.56, P < 0.0001). The active body temperature of the lizard in the wild showed monthly variations, and no effect of age or sex. In the laboratory in a gradient of 15℃–30℃, the resting body temperature (Tb) was positively correlated with ambient temperature (Ta): Tb = 12.450 + 0.5641 Ta (F1, 110=11.34, r2 = 0.997, P < 0.001). In the environment without thermal gradients, there was a significant diel variation in body temperature, air temperature and substrate temperature, but there were no significant differences in average daily body temperature, air temperature and substrate temperature. The RMR showed no difference between sexes, and it increased with ambient temperature (Ta). Further analysis indicated that the thermoregulation of Chinese crocodile lizard was conducted by both behavioral and physiological means, and both thermoregulation and the resting metabolic rates of Chinese crocodile lizard were in accordance with the thermal biology of this ectothermic species. The capability of physiological thermoregulation of Chinese crocodile lizard was relatively higher than that of other more active lizards. The thermoregulation of Chinese crocodile lizard parallels its behavioral characteristics of spending most of their time at rest [Acta Zoologica Sinica 54（6）：964–971, 2008].

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