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Search Results: 1 - 10 of 127046 matches for " and Li Guanying "
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Nonuniform Lowness and Strong Nonuniform Lowness
Li Hongzhou,and Li Guanying,
Li Hongzhou
,Li Guanying

计算机科学技术学报 , 1995,
Abstract: The concepts of the nonuniform and strong nonuniform lownesss are in-troduced. Those notions provide a uniform framework to study connectionsbetween the polynomiaLtime hierarchy and sparse sets.
A SELF-GROWING NEURAL TREE NETWORK PATTERN CLASSIFIER
一个自生成的神经树网络模式分类器

Li Jigui,Lin Guofu,Li Guanying,
李吉桂
,林国扶,李冠英

软件学报 , 1995,
Abstract: This paper is about a neural tree network(NTN)model.A supervised competitive learning algorithm is presented to grow this architecture,which can effectly solve the complex multicategory classification.A simulation result also presented on handwrited numberic recognition shows effectiveness of this classifier.
Age Effects in Foreign Language Learning for Children in China
Zhiliang Liu,Guanying Chen
English Language Teaching , 2009, DOI: 10.5539/elt.v2n1p37
Abstract: To know the age effects in foreign language learning for children in China, we made both qualitative survey on the English teachers, the students and their parents by means of questionnaire; and quantitative survey on the students’ scores from junior 1 to senior 2 (5 years) in the secondary school by analyses between those (over 30 students) who had learned English for 3 years in the elementary school and those (over 400 students) who hadn’t. Finally conclusions that “‘the younger, the better’ in FLL is doubted, FLES shouldn’t be done in lower grades of elementary school in China, qualified English teacher is the decisive factor on FLES” were drawn from the surveys on FLES in China.
Analysis of Minimizers of the Lawrence-Doniach Energy for Superconductors in Applied Fields
Patricia Bauman,Guanying Peng
Mathematics , 2014,
Abstract: We analyze minimizers of the Lawrence-Doniach energy for layered superconductors occupying a bounded generalized cylinder, $ \Omega\times[0,L]$, in $\mathbb{R}^3$, where $\Omega$ is a bounded simply connected Lipschitz domain in $\mathbb{R}^2$. For an applied magnetic field $\vec{H}_{ex}=h_{ex}\vec{e}_{3}$ that is perpendicular to the layers with $\left|\ln\epsilon\right|\ll h_{ex}\ll\epsilon^{-2}$ as $\epsilon\rightarrow 0$, where $\epsilon$ is the reciprocal of the Ginzburg-Landau parameter, we prove an asymptotic formula for the minimum Lawrence-Doniach energy as $\epsilon$ and the interlayer distance $s$ tend to zero. Under appropriate assumptions on $s$ versus $\epsilon$, we establish comparison results between the minimum Lawrence-Doniach energy and the minimum three-dimensional anisotropic Ginzburg-Landau energy. As a consequence, our asymptotic formula also describes the minimum three-dimensional anisotropic energy as $\epsilon$ tends to zero.
Exceptionally small balls in stable trees
Thomas Duquesne,Guanying Wang
Mathematics , 2011,
Abstract: The $\gamma$-stable trees are random measured compact metric spaces that appear as the scaling limit of Galton-Watson trees whose offspring distribution lies in a $\gamma$-stable domain, $\gamma \in (1, 2]$. They form a specific class of L\'evy trees (introduced by Le Gall and Le Jan in1998) and the Brownian case $\gamma= 2$ corresponds to Aldous Continuum Random Tree (CRT). In this paper, we study fine properties of the mass measure, that is the natural measure on $\gamma$-stable trees. We first discuss the minimum of the mass measure of balls with radius $r$ and we show that this quantity is of order $r^{\frac{\gamma}{\gamma-1}} (\log1/r)^{-\frac{1}{\gamma-1}}$. We think that no similar result holds true for the maximum of the mass measure of balls with radius $r$, except in the Brownian case: when $\gamma = 2$, we prove that this quantity is of order $r^2 \log 1/r$. In addition, we compute the exact constant for the lower local density of the mass measure (and the upper one for the CRT), which continues previous results.
Something about the Balancing of Thermal Motors
Raffaella Aversa, Relly Victoria V. Petrescu, Bilal Akash, Ronald B. Bucinell, Juan M. Corchado, Filippo Berto, MirMilad Mirsayar, Guanying Chen, Shuhui Li, Antonio Apicella and Florian Ion T. Petrescu
American Journal of Engineering and Applied Sciences , 2017, DOI: 10.3844/ajeassp.2017.200.217
Abstract: Internal combustion engines in line (regardless of whether the work in four-stroke engines and two-stroke engines Otto cycle engines, diesel and Lenoir) are, in general, the most used. Their problem of balancing is extremely important for their operation is correct. There are two possible types of balancing: Static and dynamic balance. The total static to make sure that the sum of the forces of inertia of a mechanism to be zero. There are also a static balance partial. Dynamic balance means to cancel all the moments (load) inertia of the mechanism. A way of the design of an engine in a straight line is that the difference between the crank 180 [°] or 120 [°]. A different type of construction of the engine is the engine with the cylinders in the opposite line, called "cylinder sportsmen". In this type of engine (regardless of their position, which is most often vertical) for engines with two cylinders, one has a static balance total and an imbalance in the dynamic. Similar to the model of the earth concentrated in rotation movement are resolved and load balancing shafts rotating parts. An important way to reduce losses of heat engines is how to achieve a better balance. The methods may be used in equal measure and on engines with external combustion, type Stirling or Watt.
SYNTHESIS OF GRAFT COPOLYMER(PVIPA-g-PIB) via CATIONIC POLYMERIZATION OF ISOBUTYLENE WITH PVIPA MACROINITIATOR/TiCl4 INITIATING SYSTEM
极性/非极性接枝共聚物PVIPA-g-PIB的合成研究*

LIU Yaochang,WU Yixian,LI Di,LI Qingyuan,FENG Li,XU Riwei,WU Guanying,
刘耀昌
,吴一弦,李狄,李庆元,冯丽,徐日炜,武冠英

高分子学报 , 2007,
Abstract: A random copolymer of(poly(vinyl) acetate-co-isopropenyl acetate)(PVIPA) with number-average molecular weight(M_n) of 9600 and relatively narrow molecular weight distribution(MWD,M_w/M_n=2.03)was prepared by free radical copolymerization of vinyl acetate with isopropenyl acetate using AIBN as initiator.Then,the cationic polymerizations of isobutylene were carried out by using the above copolymer PVIPA as macroinitiator in conjunction with coinitiator TiCl_4 in the absence of an external nucleophilic additive.The effects of TiCl_4],PVIPA],the ageing temperature and time on monomer conversion and initiation efficiency of PVIPA,molecular weight and molecular weight distribution were investigated.Both PVIPA and H_2O in the polymerization system would complex with Lewis acid TiCl_4 to form the two different active centers(A) and(B).(A) and(B) initiated the cationic polymerization of isobutylene(IB) in competition and led to PVIPA-g-PIB and homopolymer PIB,respectively.The copolymerization product was extracted by methanol to remove unreacted macroinitiator.The initiation efficiency of PVIPA was dependent on TiCl_4],,the ageing temperature and time.The polymerization could be started under the condition of enough concentration of TiCl_4 and the initiation efficiency of PVIPA increased with increases in TiCl_4] and or a decrease in or at lower ageing temperature or for longer ageing time.However,the initiation from(B) increased when TiCl_4 was at high concentrationc.The initiation efficiency of PVIPA increased up to around 90% under the appropriate conditions.The graft copolymer PVIPA-g-PIB with M_n of 163700 and polydispersity of 2.17 could be obtained under proper reaction conditions.Furthermore,the initiation efficiency was also increased by introduction of small amount of 2,6-dimethyl pyridine(DMP).
Intra-articular injection of xanthan gum: A potential therapy for osteoarthritis  [PDF]
Huarong Shao, Guanying Han, Peixue Ling, Xiqiang Zhu, Fei Liu, Yan Jin, Lijuan Zhao, Tianmin Zhang
Advances in Bioscience and Biotechnology (ABB) , 2012, DOI: 10.4236/abb.2012.324063
Abstract: Osteoarthritis (OA) means inflammation of the joints, with the symptoms of joint pain, stiffness, and swelling of the joints. It is a degenerative disease that appears to be caused by both biomechanical and bio-chemical factors. Intra-articular (IA) injection treatment is one of the main treatment methods for OA because of its positive effect in reducing joint pain and increasing joint mobility. IA injection of xanthan gum (XG) could protect the joint cartilage, relieve the synovitis and reduce the OA progression in experiment OA. The injection of XG may have a long-lasting effect in the joint cavity, which could avoid frequent IA injections. However, for the development of this potential therapy, further studies such as the effective long-term pain relief properties, the detailed action mechanism and the pharmacokinetics of the XG injection will be conducted. This article briefly reviewed the preparation, safety evaluation, pharmacodynamics and possible action mechanism of XG injection, and come up with the ideas for further development of this potential therapy for OA.
CONTROLLED CATIONIC POLYMERIZATION OF ISOBUTYLENE WITH HES/TiCl4 INITIATING SYSTEM
HES/TiCl4体系引发异丁烯可控正离子聚合

LIANG Lihu,WU Yixian,LI Yan,XU Riwei,YANG Wantai,WU Guanying,
梁立虎
,吴一弦,李艳,徐日炜,杨万泰,武冠英

高分子学报 , 2008,
Abstract: 由六官能团引发剂环氧化角鲨烯(HES)与TiCl4组成引发体系,引发异丁烯(IB)在CH2Cl2/n-Hex(40/60,V/V)混合溶剂中进行正离子聚合,分别探讨了HES和2,6-二甲基吡啶(DMP)用量对IB正离子聚合转化率、产物分子量及其分布的影响.结果表明HES和微量水均可与TiCl4发生络合,并分别形成碳正离子和质子两种引发活性中心,导致聚合产物GPC谱图呈明显双峰分布.增加引发剂HES用量(HES]=2.64mmol/L),可以减少聚合体系中微量水的不可控引发,提高HES引发效率;在聚合体系中引入少量DMP时,可明显地减少微量水的不可控引发和提高HES的引发效率,使得即使在较低HES用量下(HES]=0.084mmol/L),也可达到主要由HES引发IB正离子聚合,制备出官能叔氯末端的六臂星形支化遥爪聚异丁烯,GPC谱图呈现单峰分子量分布,分布指数为1.5左右.
CATIONIC POLYMERIZATION OF ISOBUTYLENE WITH DCC/AlCl3 INITIATING SYSTEM
DCC/AlCl3体系引发异丁烯正离子聚合

LIU Xun,WU Yixian,ZHANG Chenglong,ZHANG Pei,LI Yan,XU Xu,WU Guanying,
刘迅
,吴一弦,张成龙,张蓓,李艳,徐旭,武冠英

高分子学报 , 2007,
Abstract: The cationic polymerization of isobutylene (IB) by utilizing difunctional initiator dicumyl chloride (DCC) in conjunction with coinitiator AlCl3 was carried out in CH2Cl2/Hex (40/60,V/V) solvent mixtures in the absence or in the presence of 2,6-dimethylpyridine (DMPy) and triphenylamine (TPA) respectively.The effects of concentrations of DCC,electron donor and AlCl3 on monomer conversion,molecular weight and molecular weight distribution (MWD) of the product polyisobutylene (PIB) were investigated systematically.The small amount of water in the polymerization system in conjunction with AlCl3 induced a conventional uncontrolled rapid polymerization of IB and led to polyisobutylene with broad molecular weight distribution.It is found that the GPC trace of resultant polymer obtained by DCC/H2O/AlCl3 system exhibit a bimodal distribution,which was attributed to the competition of initiation from two different active centers,i.e.,H+AlCl3OH- (A) and AlCl4-+C(CH3)2C6H4(CH3)2C+-AlCl4 (B).The initiation from active center (B) increased in the polymerization system with an increase in DCC concentration.A large dosage of DCC (DCC/H2O=5.3) was needed to decrease the initiation from active center (A) effectively,and the polymer with low molecular weight (about 1.8×104) was obtained.According to the characterization results of GPC,NMR and UV,both the initiation efficiency of DCC and molecular weight of polymer increased and MWD narrowed by addition of small amount of TPA or DMPy.The mechanistic role of TPA or DMPy was to decrease the uncontrolled initiation of proton from active center (A) and the chain transfer reaction to monomer.The monomer conversion decreased, but the initiation efficiently increased, and MWD narrowed with increasing of TPA or DMPy concentration.The initiation from active center (A) could be suppressed at high DCC concentration or even at low DCC concentration in the presence of TPA or DMPy.A desirable cationic polymerization of IB would be achieved with DCC/AlCl3 initiation system in the presence of adequate amount of TPA or DMPy, and polyisobutylene with relatively high molecular weight and relatively narrow unimodal molecular weight distribution could be obtained.
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