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The Spectrum Sequences of Periodic Frame Multiresolution Analysis

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Acta Mathematica Sinica,English Series 2009年第3期25卷 403-418页

作者： Yun Zhang LI qiao fang LIAN College of Applied Sciences Beijing University of Technology Beijing 100124 P. R. China Department of Mathematics Beijing Jiaotong University Beijing 100044 P. R. China

The periodic multiresolution analysis （PMRA） and the periodic frame multiresolution analysis （PFMRA） provide a general recipe for the construction of periodic wavelets and periodic wavelet frames, respectively. This paper addresses PFMRAs by the introduction of the notion of spectrum sequence. In terms of spectrum sequences, the scaling function sequences generating a normalized PFMRA are characterized; a characterization of the spectrum sequences of PFMRAs is obtained, which provides a method to construct PFMRAs since its proof is constructive; a necessary and sufficient condition for a PFMRA to admit a single wavelet frame sequence is obtained; a necessary and sufficient condition for a PFMRA to be contained in a given PMRA is also obtained. What is more, it is proved that an arbitrary PFMRA must be contained in some PMRA. In the meanwhile, some examples are provided to illustrate the general theory.

关键词： PFMRA periodic wavelet frame scaling function sequence spectrum spectrum sequence

Density Results for Subspace Multiwindow Gabor Systems in the Rational Case

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Acta Mathematica Sinica,English Series 2013年第5期29卷 897-912页

作者： qiao fang LIAN Hai Li MA Department of Mathematics Beijing Jiaotong University

Let S be a periodic set in R and L2（S） be a subspace of L2（R）. This paper investigates the density problem for multiwindow Gabor systems in L2（S） for the case that the product of time- frequency shift parameters is a rational number. We derive the density conditions for a multiwindow Gabor system to be complete （a frame） in L2（S）. Under such conditions, we construct a multiwindow tight Gabor frame for L2 （S） with window functions being characteristic functions. We also provide a characterization of a multiwindow Gabor frame to be a Riesz basis for L2（S）, and obtain the density condition for a multiwindow Gabor Riesz basis for L2 （S）.

关键词： Multiwindow Gabor frames Riesz bases subspaces Zak transform density conditions

Microstructure changing and moisture removing of lychee during microwave vacuum drying

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International Journal of Agricultural and Biological Engineering 2016年第3期9卷 162-169页

作者： Huang Luelue qiao fang Fan Daming School of Applied Chemistry and Biological Technology Shenzhen PolytechnicShenzhen 518055China State Key Laboratory of Food Science and Technology School of Food Science and TechnologyJiangnan UniversityWuxi 214122China

Micrographs of lychee pericarp and pulp during microwave vacuum drying were tested and analyzed in order to illuminate the microstructure change of lychee and effect of the change on moisture removing in *** results showed that the pericarp consisted of three parts:outer layer with cuticle,inter layer and inner *** layer and inter layer cells are easily destroyed than inner layer because of small and intact inner layer ***,micrographs showed that the moisture content of pulp keep constant with the temperature increasing at first 40 min due to the inner layer cells prevent the moisture removing from *** long tubular structure of pulp cell would become break and lost over time,because the intercellular spaces reduced and the moisture removing was slow down in ***,the microstructure of lychee dried with temperature control was better than that without temperature control.

关键词： Lychee microstructure microwave vacuum drying moisture removal temperature profile

Black tea markets worldwide: Are they integrated?

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Journal of Integrative Agriculture 2022年第2期21卷 552-565页

作者： XU Yong-mei qiao fang-bin HUANG Ji-kun School of Economics Zhejiang Gongshang UnviersityHangzhou 310018P.R.China China Economics and Management Academy Central University of Finance and EconomicsBeijing 100081P.R.China China Center for Agricultural Policy Peking UniversityBeijing 100871P.R.China

Global tea consumption has risen significantly alongside rapid expansion of international trade in recent ***,few studies have systematically examined the relationship among the major tea markets *** weekly data from 2012-2019,this study empirically analyzed the price series of the world’s major black tea auction *** estimation results showed that these markets are connected,even though heterogeneities *** finding holds not only for regional markets but also for international *** findings offer important implications for tea-producing countries with millions of smallholder farmers.

关键词： black tea market price integration VECM

Analysis of the extremely cold and heavy snowfall in North America in January 2015

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Atmospheric and Oceanic Science Letters 2016年第2期9卷 75-82页

作者： CUI Hong-yan qiao fang-li First Institute of Oceanography State Oceanic Administration Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration

With global warming and declining Arctic sea ice area in autumn observed by satellites since 1979, anomalous cold snaps in recent winters have affected large parts of North America, Europe, and East Asia. In January 2015, North America suffered extremely cold and heavy snowfall events. As revealed in this paper, the NCEP reanalysis data show that the temperature decreased significantly in January 2015 in North America, including the air temperature in the troposphere and the surface air temperature. Moreover, snow cover increased obviously in January 2015 in North America, while there was a significant negative anomaly of geopotential height. The wind formed the anomalous pattern, which favored cold currents blowing to the North American continent from the polar region, and bringing plenty of water vapor. Our results suggest that the anomalous north wind and decreasing westerly jet stream, which allowed cold and moist air to easily penetrate the North American continent from the Arctic, was one of the main reasons for the extremely cold and heavysnow winter of 2015 in North America.

关键词： Snowfall cold winter atmospheric circulation geopotential height strong north wind

Optimized Local Trigonometric Bases with Nonuniform Partitions

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Acta Mathematica Sinica,English Series 2006年第4期22卷 1069-1084页

作者： qiao fang LIAN Yong Ge WANG Dun Yan YAN Department of Mathematics Beijing Jiaotong University Beijing 100044 P. R. China Department of Applied Mathematics Beijing University of Aeronautics and AstronauticsBeijing 100083 P. R. China Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 P. R. China School of Information Science and Engineering the Graduate School of the Chinese Academy of Sciences Beijing 100039 P. R. China

The authors provide optimized local trigonometric bases with nonuniform partitions which efficiently compress trigonometric functions. Numerical examples demonstrate that in many cases the proposed bases provide bette... 详细信息

关键词： Optimized local trigonometric bases Bell functions Nonuniform partitions

2-ORDER TURBULENCE CLOSURE PLANKTON ECOSYSTEM DYNAMICS MODEL AND ITS APPLICATION

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Journal of Hydrodynamics 2001年第3期13卷 17-23页

作者： Wan, Zhen-Wen Yuan, Ye-Li qiao, fang-Li State Oceanic Administration Qingdao 266003 China

The basic concepts of continuous neurogen dynamics, particle and continuous mass, were cited to describe plankton ecosystems, so a continuous neurogen dynamics model of plankton ecosystem was developed by logically reasoning with less ecological experiential relation. For precise parameterization of diffusion acted on plankton by hydrodynamics, the scheme of 2-order turbulence closure of geophysical fluid dynamics was generalized to enclose the equations of plankon ecosystem dynamics model. This model was applied to simulate a natural ecological process in Jiaozhou Bay. Comparison between simulation and data showed the exciting prognosis ability of this model.

关键词： Ecosystems Mathematical operators Numerical analysis Simulation Turbulence

Vibration Characteristics of Rotor System with Loose Disc Caused by the Insufficient Interference Force

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Chinese Journal of Mechanical Engineering 2022年第3期35卷 297-311页

作者： Zhinong Li fang qiao Wenxiu Lu Jie Liu Dong Wang Fulei Chu Key Laboratory of Nondestructive Testing Ministry of EducationNanchang Hangkong UniversityNanchang 330063China Laboratory of Science and Technology on Integrated Logistics Support National University of Defense TechnologyChangsha 410073China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China State Key Laboratory of Mechanical Systems and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

The rotating parts looseness is one of the common failures in rotating *** current researches of looseness fault mainly focus on non-rotating ***,the looseness fault of disc-shaft system,which is the main work part in the rotor system,is almost ***,a dynamic model of the rotor system with loose disc caused by the insufficient interference force is proposed based on the contact model of disc-shaft system with the microscopic surface topography,the vibration characteristics of the system are analyzed and discussed by the number simulation,and verified by the *** results show that the speed of the shaft,the contact stiffness,the clearance between the disc and shaft,the damping of the disc and the rotational damping have an influence on the rotation state of the *** the rotation speed of the disc and the shaft are same,the collision frequency is mainly composed of one frequency multiplication component and very weak high frequency multiplication *** the rotation speed of the disc and the shaft is close,the vibration of the disc occurs a beat vibration phenomenon in the horizontal ***,a periodical similar beat vibration phenomenon also occurs in the waveform of the disc-shaft displacement *** collision frequency is mainly composed of a low frequency and a weak high frequency *** the rotation speed of the disc and the shaft has great difference,the collision frequency is mainly composed of one frequency multiplication,a few weak high frequency multiplication components and a few low frequency multiplication *** the reduction of the relative speed of the disc,the trajectory of the disc changes from circle-shape to inner eight-shape,and then to *** the inner eight-shape,the inner ring first gradually becomes smaller and then gradually becomes larger,and the outer ring is still getting *** obtained research results in this paper has importa

关键词： Rotor system with loose disc Rotor dynamics Nonlinear dynamic characteristic Nonlinear vibration Insufficient interference force Fault diagnosis

Double-edged effect of sodium citrate in Nile tilapia(Oreochromis niloticus):Promoting lipid and protein deposition *** hyperglycemia and insulin resistance

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Animal Nutrition 2023年第3期14卷 303-314页

作者： Jun-Xian Wang fang qiao Mei-Ling Zhang Li-qiao Chen Zhen-Yu Du Yuan Luo Laboratory of Aquaculture Nutrition and Environmental Health(LANEH) School of Life SciencesEast China Normal UniversityShanghaiChina

Citrate is an essential substrate for energy metabolism that plays critical roles in regulating glucose and lipid metabolic ***,the action of citrate in regulating nutrient metabolism in fish remains poorly ***,we investigated the effects of dietary sodium citrate on growth performance and systematic energy metabolism in juvenile Nile tilapia(Oreochromis niloticus).A total of 270Nile tilapia(2.81±0.01 g)were randomly divided into three groups(3 replicates per group,30 fish per replicate)and fed with control diet(35%protein and 6%lipid),2%and 4%sodium citrate diets,respectively,for 8 *** results showed that sodium citrate exhibited no effect on growth performance(P>0.05).The whole-body crude protein,serum triglyceride and hepatic glycogen contents were significantly increased in the 4%sodium citrate group(P0.05).The 4%sodium citrate treatment significantly increased the serum glucose and insulin levels at the end of feeding trial and also in the glucose tolerance test(P<0.05).The 4%sodium citrate significantly enhanced the hepatic phosphofructokinase activity and inhibited the expression of pyruvate dehydrogenase kinase isozyme 2 and phosphor-pyruvate dehydrogenase E1 component subunit alpha proteins(P<0.05).Additionally,the 4%sodium citrate significantly increased hepatic triglyceride and acetyl-Co A levels,while the expressions of carnitine palmitoyl transferase 1a protein were significantly down-regulated by the 4%sodium citrate(P<0.05).Besides,the 4%sodium citrate induced crude protein deposition in muscle by activating m TOR signaling and inhibiting AMPK signaling(P<0.05).Furthermore,the 4%sodium citrate significantly suppressed serum aspartate aminotransferase and alanine aminotransferase activities,along with the lowered expression of pro-inflammatory genes,such as nfκb,tnfa and il8(P<0.05).Although the 4%sodium citrate significantly increased phosphor-nuclear factor-k B p65 prote

关键词： Sodium citrate Lipid and protein deposition Insulin resistance Nile tilapia