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Instantaneous Frequency Estimation Based on the Wigner-Ville Distribution Associated with linear Canonical Transform(WDL)

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Chinese Journal of Electronics 2018年第1期27卷 123-127页

作者： liU Lubo LUO Maokang lai li College of Mathematics Sichuan University

The Instantaneous frequency(IF) is a basic concept in theory and application of signal processing. Wigner-Ville distribution(WVD) is a powerful tool in IF estimation, but it is sensitive to the noise. The linear canonical transform(LCT) has been proved to be very powerful for non-stationary signal processing. A new definition of Wigner-Ville distribution associated with the linear canonical transform(WDL) has been put forward. In this case, this paper proposes a new IF estimation method which is suitable for processing non-stationary signals. This new method is useful in IF estimation. This new method is more accurate and antinoise than the one based on the WVD. Simulations demonstrated the derived results.

关键词： Instantaneous frequency Wigner-Vill distribution linear canonical transform Wigner-Ville distribution associated with the linear canonical transform Instantaneous frequency estimation

Colorectal cancer,one entity or three

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第3期10卷 219-229页

作者： Feng-ying li Mao-de lai Department of Pathology School of Medicine Zhejiang University Hangzhou 310058 China

Understanding of the mechanism of colorectal carcinogenesis has been gaining momentum for some years on account of its high incidence and impact on the lives of individuals affected. Different genetic abnormalities have been found in colorectal cancers from different sites. For example, proximal colon cancer is usually related to the nucleotide instability pathway, as microsatellite instability （MSI）. However, distal colon cancer is usually associated with specific chromosomal instability （CIN）. The development of cancer at the rectum, though similar to that at the colon, displays its own unique features. These differences might be partially attributed to different embryological development and physiological circumstances. Environmental factors such as diet and alcohol intake also differ in their role in the development of tumors in the three segments, proximal colon, distal colon, and rectum. ＂Proximal shift＂ of colon cancer has been known for some time, and survival rates of colorectal cancer are higher when rectal cancers are excluded, both of which emphasize the three different segments of coloreetal cancer and their different properties. Meanwhile, colonic and rectal cancers are distinctive therapeutic entities. The concept of three entities of coloreetal cancer may be important in designing clinical trails or therapeutic strategies. However, the dispute about the inconsistency of data coneerning the site-specific mechanism of eolorectal carcinoma does exist, and more evidence about molecular events of carcinogenesis and targeted therapy needs to be collected to definitely confirm the conception.

关键词： Colorectal cancer Proximal colon Distal colon Rectum Carcinogenesis Epidemiology and prognosis

Geomorphology and Environmental Management of the Yellow River Source Zone

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Journal of Mountain Science 2013年第4期10卷 628-631页

作者： BRIERLEY Gary li Xi-lai School of Environment University of Auckland Private Bag 92019Auckland New Zealand College of Agriculture and Animal Husbandry Qinghai University

Geologic,climatic and anthropogenic factors have fashioned the distinctive landscapes and ecosystems of the Yellow River source zone(Brierley and Huang2013;Figure1).Located at thenorth-east corner of the Qinghai-Tibet... 详细信息

关键词：黄河源区环境管理土地利用方式半干旱气候地貌生态系统生物多样性人为因素

Tomato Key Sucrose Metabolizing Enzyme Activities and Gene Expression Under NaCl and PEG Iso-Osmotic Stresses

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Agricultural Sciences in China 2009年第9期8卷 1046-1052页

作者： LU Shao-wei li Tian-lai JIANG Jing The Key Laboratory of Protected Horticulture of liaoning Province/College of Horticulture Shenyang Agricultural University Shenyang 110161. P.R. China

Changes in sucrose metabolism in response to salt （NaC1） and water （polyethylene glycol, PEG6000） iso-osmotic stresses were measured in tomato cultivar liaoyuan Duoli （Solanum lycopersicum L.） and the objective was to provide a new evidence for the relationship between salt and osmotic stresses. The carbohydrate contents, as well as sucrose metabolizing enzymes activities and transcript levels were determined. The results indicated that soluble sugar and hexoses accumulated to higher levels and the contents of sucrose and starch were lower in mature fruit under the two stress treatments. Salt and water stresses can enhance the invertase and sucrose synthase activities of tomato fruit in a long period of time （45-60 days after anthesis）, and elevate the expression of soluble acid invertase mRNA. It showed that two different stresses could also regulate the soluble acid invertase activity by controlling its gene expression. The activity of sucrose synthase was linked to the changes in soluble sugar levels but not with transcript levels. The effects of salt and water stress treatments on sucrose phosphate synthase activities were weak.

关键词： tomato salt stress water stress sucrose metabolism gene expression

On the Local Wellposedness of Three-dimensional MHD System in the Critical Spaces

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Acta Mathematicae Applicatae Sinica 2015年第3期31卷 607-622页

作者： Zi-lai li Mei WANG J.YANG School of Mathematics Northwest University School of Mathematics and Information Science Henan Polytechnic University

In this article, we prove the local wellposedness of Three-Dimensional incompressible magnetohydrodynamic system（MHD） with initial data in the critical spaces, without assumptions of small density variation.

关键词： Magneto-hydrodynamics system littlewood-Paley theory critical spaces

EXPERIMENTS ON HYDRODYNAMIC INTERACTION BETWEEN 3-D OVAL AND WALL

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Journal of Hydrodynamics 2007年第1期19卷 121-126页

作者： SUN Ke SHENG Qi-hu ZHANG liang li Feng-lai College of Shipbuilding Engineering Harbin Engineering University Harbin 150001 China

The boundary hydrodynamic interaction of a 3-D oval body was experimentally surveyed for different cases. The regression method was employed to fred the experimental formulae of hydrodynamic coefficients relating to the attack angle, clearance to wall, and moving speed. The mechanism of interaction was discussed. The experimental results show that there exists a lifting effect, similar to wings in flow. The lifting effect is remarkable. The boundary hydrodynamic interaction of the small aspect ratio model is almost linearly dependent on the attack angle, but the effect of the moving speed of the body on the hydrodynamic coefficients is very small. The effect of clearance is related to the geometric shape. The boundary hydrodynamic interaction always enhances the lifting effect if the clearance is small.

关键词： hydrodynamic coefficient model experiment,boundary interaction oval

Collective stochastic resonance behaviors of two coupled harmonic oscillators driven by dichotomous fluctuating frequency

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Chinese Physics B 2021年第6期30卷 176-187页

作者： Lei Jiang li lai Tao Yu Maokang Luo College of Mathematics Sichuan UniversityChengdu 610064China College of Aeronautics and Astronautics Sichuan UniversityChengdu 610064China

The collective behaviors of two coupled harmonic oscillators with dichotomous fluctuating frequency are investigated,including stability, synchronization, and stochastic resonance(SR). First, the synchronization condition of the system is obtained. When this condition is satisfied, the mean-field behavior is consistent with any single particle behavior in the system. On this basis, the stability condition and the exact steady-state solution of the system are derived. Comparative analysis shows that, the stability condition is stronger than the synchronization condition, that is to say, when the stability condition is satisfied, the system is both synchronous and stable. Simulation analysis indicates that increasing the coupling strength will reduce the synchronization time. In weak coupling region, there is an optimal coupling strength that maximizes the output amplitude gain(OAG), thus the coupling-induced SR behavior occurs. In strong coupling region, the two particles are bounded as a whole, so that the coupling effect gradually disappears.

关键词： coupled harmonic oscillators dichotomous fluctuating frequency synchronization stability stochastic resonance

Correlation Between Endogenous Hormones of Stem Apices and Fruit Locule Numbers in Tomatoes During Floral Bud Differentiation Stages

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Agricultural Sciences in China 2008年第4期7卷 447-454页

作者： li Yue li Tian-lai WANG Dan Key Laboratory of Protected Horticulture of liaoning Province/College of Horticulture Shenyang Agricultural University/Technological Research Center of High Efficient Protected Agriculture of Liaoning Province Shenyang 110161 P.R.China College of Environment Liaoning University Shenyang 110036 P.R.China

The study was designed to elucidate the changes in the endogenous hormones of stem apices in tomatoes and the function of correlative endogenous hormones in tomatoes during floral bud differentiation stages. The tomato parents were crossed and reverse crossed by using two inbred lines of multi-locule （MLK1） and few-locule （FL1） with significant difference, and the relationship between endogenous hormones GA3, IAA, and ABA levels and ovary locule numbers of parents and progeny during floral bud differentiation initial stage, floral bud differentiation stage, sepal petal formation stage, carpel formation initial stage, and ovary locule complete formation stage was studied. GA3 levels in P1, P2, F1, and RF1 were consistent with locule numbers, and IAA and ABA levels were reverse to ovary locule numbers during the key stage. The correlation showed that, during sepal petal formation stage, the ovary locule numbers were positively correlated with GA3, GA3/IAA, and GA3/ABA, and were negatively correlated with IAA and ABA. It was speculated that increasing GA3 levels or decreasing IAA and ABA levels of stem apices in tomato might be able to enhance ovary locule numbers. The sepal petal formation stage was an important stage which regulated endogenous hormones in the ovary locule formation.

关键词： tomato endogenous hormones locule numbers correlation

Advanced Studies on Rhizoma Dioscoreae Collettii

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Chinese Journal of Integrative Medicine 2020年第3期26卷 235-240页

作者： li lai-lai MENG Xiao-wei FAN Ke-tao WANG Yan-yan XIAO Yang WANG Yi Institute of Traditional Chinese Medicine Research Tianjin State Key Laboratory of Modern Chinese Medicine Tianjin University of Traditional Chinese Medicine

Rhizoma Dioscoreae Collettii,is known as Huang Dioscorea collettii,Rhizoma Coptidis Brevisepalae or yellow *** is neutral in nature and bitter in taste which is described to Gan(liver)meridian,Wei(Stomach)meridian and Pangguang(Bladder)*** was often used in the treatment of chyloid stranguria,gonorrhea,leucorrhagia,rheumatism arthralgia pain,joints disable,and lumbar knee pain syndrome in clinical.

关键词： Rhizoma Dioscoreae Collettii identification chemical constituents pharmacology clinical application