http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
The generalized Fermat type difference equations
Kai Liu,Lei Ma,Xiaoyang Zhai 대한수학회 2018 대한수학회보 Vol.55 No.6
This paper is to consider the generalized Fermat difference equations with different types which ever considered by Li \cite{li}, Ishizaki and Korhonen \cite{IK}, Zhang \cite{zhangjie} and Liu \cite{liuk4,11,1177,liu}, respectively. Some new observations and results on these equations will be given.
Sesquiterpenoids with Various Carbocyclic Skeletons from the Flowers of <i>Chrysanthemum indicum</i>
Liu, Lei-Lei,Ha, Thi Kim Quy,Ha, Wei,Oh, Won Keun,Yang, Jun-Li,Shi, Yan-Ping American Society of Pharmacognosy 2017 Journal of natural products Vol.80 No.2
<P>A phytochemical investigation of the flowers of Chrysanthemum indicum yielded sesquiterpenoids 1-25 with various carbocyclic skeletons, including 10 new (1-10) and 15 known (11-25) analogues. The structures were elucidated via their physical data, while the absolute configuration of compounds 6, 8, and 10 was assessed via electronic circular dichroism analysis. The evaluation of the effect of sesquiterpenoids on porcine epidemic diarrhea virus (PEDV) replication showed that compounds 1-5, 12, 14, 16, 17, 19, and 21 increased cell viability against cell death in PEDV-injected cells. Compounds 2, 12, and 17 were selected and investigated for their inhibition of proteins required for PEDV replication. Compounds 2 and 17 significantly reduced PEDV nucleocapsid and spike protein synthesis compared with azauridin as a positive control.</P>
Liu, Lei,Jin, Jing,Hou, Fengxiao,Li, Shengjuan,Lee, Chang-Ha Pergamon Press 2017 Energy Vol.125 No.-
<P><B>Abstract</B></P> <P>To investigate the role of a curved char surface in the nitric oxide (NO)-char reaction, single-wall carbon nanotubes (SWCNTs) were proposed as a model for simulating the curved char surface in first-principles calculations. The effect of calcium and potassium decoration on the adsorption of NO was compared for SWCNTs and graphene, the latter of which represented a flat char surface. The contribution of a curved surface to the NO-char reaction was insignificant in the absence of metals, as the binding energy of NO on pure SWCNTs was only 13% of that on pure graphene. In contrast, when calcium or potassium was present, NO adsorption on the curved surface became significant as the binding energies of NO on calcium- or potassium-decorated SWCNTs increased to 72% and 18% of those on the corresponding decorated graphene surfaces, respectively. The catalytic effect of calcium and potassium was attributed to electron transfer and backdonation between the 4s- and 3d-orbitals of the metal atoms and the NO molecule. Thus, the studies into NO adsorption on flat and curved char surfaces render it possible to determine the degree of catalytic effect of these two metals on the char surface during fuel reburning.</P> <P><B>Highlights</B></P> <P> <UL> <LI> SWCNTs were proposed to simulate the curved char surface in the fuel reburning. </LI> <LI> The catalytic effects of Ca and K were studied by Ca- or K-decorated SWCNTs. </LI> <LI> Without Ca or K, the binding energy of NO on curved char surface was trivial. </LI> <LI> When Ca or K was present, NO adsorption on the curved surface became significant. </LI> <LI> Electrons of Ca and K in 4s- and 3d-orbitals transferred to the NO molecule. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
LIE TRIPLE DERIVATIONS ON FACTOR VON NEUMANN ALGEBRAS
Liu, Lei Korean Mathematical Society 2015 대한수학회보 Vol.52 No.2
Let $\mathcal{A}$ be a factor von Neumann algebra with dimension greater than 1. We prove that if a linear map ${\delta}:\mathcal{A}{\rightarrow}\mathcal{A}$ satisfies $${\delta}([[a,b],c])=[[{\delta}(a),b],c]+[[a,{\delta}(b),c]+[[a,b],{\delta}(c)]$$ for any $a,b,c{\in}\mathcal{A}$ with ab = 0 (resp. ab = P, where P is a fixed nontrivial projection of $\mathcal{A}$), then there exist an operator $T{\in}\mathcal{A}$ and a linear map $f:\mathcal{A}{\rightarrow}\mathbb{C}I$ vanishing at every second commutator [[a, b], c] with ab = 0 (resp. ab = P) such that ${\delta}(a)=aT-Ta+f(a)$ for any $a{\in}\mathcal{A}$.
Nonbinary Multiple Rate QC-LDPC Codes with Fixed Information or Block Bit Length
Liu, Lei,Zhou, Wuyang,Zhou, Shengli The Korea Institute of Information and Commucation 2012 Journal of communications and networks Vol.14 No.4
In this paper, we consider nonbinary quasi-cyclic low-density parity-check (QC-LDPC) codes and propose a method to design multiple rate codes with either fixed information bit length or block bit length, tailored to different scenarios in wireless applications. We show that the proposed codes achieve good performance over a broad range of code rates.
The Structural Design of Tianjin Goldin Finance 117 Tower
Liu, Peng,Ho, Goman,Lee, Alexis,Yin, Chao,Lee, Kevin,Liu, Guang-lei,Huang, Xiao-yun Council on Tall Building and Urban Habitat Korea 2012 International journal of high-rise buildings Vol.1 No.4
Tianjin Goldin Finance 117 tower has an architectural height of 597 m, total of 117 stories, and the coronation of having the highest structural roof of all the buildings under construction in China. Structural height-width ratio is approximately 9.5, exceeding the existing regulation code significantly. In order to satisfy earthquake and wind-resisting requirements, a structure consisting of a perimeter frame composed of mega composite columns, mega braces and transfer trusses and reinforced concrete core containing composite steel plate wall is adopted. Complemented by some of the new requirements from the latest Chinese building seismic design codes, design of the super high-rise building in high-intensity seismic area exhibits a number of new features and solutions to professional requirements in response spectrum selection, overall stiffness control, material and component type selection, seismic performance based design, mega-column design, anti-collapse and stability analysis as well as elastic-plastic time-history analysis. Furthermore, under the prerequisite of economic viability and a series of technical requirements prescribed by the expert review panel for high-rise buildings exceeding code limits, the design manages to overcome various structural challenges and realizes the intentions of the architect and the client.
Design and evaluation of spur gear pairs with improved bearing capacity and lubrication performance
Lei Liu,Zhiwei Chen,Rong Kong 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.3
The tooth form is the most influential factor on the bearing capacity and operation performance of a gear drive. Tooth profiles of spur gears can be designed based on control of relative curvature of conjugate profiles, but how to conceive appropriate control strategies and appraise gear pairs accurately needs to be investigated in depth. This paper presents the control strategies through analysis of the effect mechanisms of relative curvature on the bearing capacity and lubrication performance. Evaluation approaches of the gear pairs are then proposed by establishing the analytical models (AMs). In case studies, gear pairs with optimal comprehensive performance are designed through five control strategies. The AMs for contact and bending capacity are validated with the finite element models. The effects of the control strategies are discussed through comparative analysis. Results reveal that the control strategies lead to remarkable enhancement of bearing capacity and lubrication performance.
THE GENERALIZED FERMAT TYPE DIFFERENCE EQUATIONS
Liu, Kai,Ma, Lei,Zhai, Xiaoyang Korean Mathematical Society 2018 대한수학회보 Vol.55 No.6
This paper is to consider the generalized Fermat difference equations with different types which ever considered by Li [14], Ishizaki and Korhonen [9], Zhang [26] and Liu [15-18], respectively. Some new observations and results on these equations will be given.
Lei Luo,Zhiyi Liu,Song Bai,Jing Cao,Fei Liu,Linnan Ou,Juangang Zhao 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.9
The microstructures and mechanical properties of a hot extruded Al–Zn–Mg–Cu alloy pipe with variable cross-section areinvestigated by transmission electron microscopy, electron backscattering diffraction, hardness testing and finite elementmethod. The results suggest that the variable temperature distribution at different positions along the extrusion directionafter hot extrusion attribute to the changes in hot deformation degrees. The extruded profile at billet temperature of 410 °Cand a ram speed of 1.5 mm/s shows a gradual increase in temperature from 416 to 467 °C at strains from 3.7 to 8.6 alongthe extrusion direction. The dynamic recovery (DRV) and partial dynamic recrystallization (DRX) are observed in the hotextruded profile, and high-angle grain boundaries fraction exponentially rises along the extrusion direction. The hardnessat different positions of the hot extruded profile shows a nearly exponential decline along the extrusion direction, mainlyascribes to the decrease of the dislocation density that caused by the dynamic softening.
Genetic Variability of mtDNA Sequences in Chinese Native Chicken Breeds
Liu, Z.G.,Lei, C.Z.,Luo, J.,Ding, C.,Chen, G.H.,Chang, H.,Wang, K.H.,Liu, X.X.,Zhang, X.Y.,Xiao, X.J.,Wu, S.L. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.7
The variability of mtDNA hypervariable segment I (HVS I) sequences was investigated in a total of 48 birds belonging to 12 Chinese native chicken breeds. Sixteen haplotypes were identified from 35 polymorphic nucleotide sites which accounted for 6.4% of a sequenced 544 bp fragment. Diversity analysis of the haplotypes showed that Tibetan, Langshan and Henan cockfight chicken had only one haplotype, while ancient haplotypes existed in Taihe silky and Chahua chicken. Phylogenetic analysis of the haplotypes suggested that Chinese native chicken breeds shared 5 maternal lineages and some breeds would share the same maternal lineage, regardless of their external features and ecological types. Both divergent and phylogenetic analysis of the haplotypes indicated the close genetic relationships between the Chinese native chicken breeds and G. g. gallus and G. g. spadiceus from different areas, which implied that G. g. gallus and G. g. spadiceus were the original ancestors of the Chinese native chicken breeds.