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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

Simulation of wind-driven circulation and temperature in the near-shore region of southern Lake Michigan by using a channelized model

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Journal of Hydrodynamics 2013年第1期25卷 97-111页

作者： LIU lubo FU Xu-dong WANG Guang-qian Department of Civil and Geomatics Engineering Lyles College of Engineering California State University State Key Laboratory of Hydroscience and Engineering Tsinghua University

To enhance the efficiency of a pathogen forecasting model in the beach areas of southern Lake Michigan and to reduce the computation time, the near-shore current is approximated as a channelized flow parallel to the shorelines in clockwise or anti-clock- wise direction within the accuracy tolerance range. A channelized model with a curvilinear boundary can significantly reduce the computation effort, and at the same time achieve a good agreement between the predicted and measured water surface elevations, currents, and water temperatures. The sensitivity analysis results show that the suitable channel width for the near-shore region of southern Lake Michigan should be no less than 10 kin. The modeling results of the water temperature are much less sensitive to the channel width than those of the current velocity and the water surface elevation. The modeling results also show a close correlation between the speeds of the wind and the near-shore current. The current may fully respond the wind stress with a time lag of several hours. The correlation may provide an approximate estimation of the lake circulation under some wind conditions for a practical fore- casting purpose. More complex wind-current relationships need to be described with a more sophisticated hydrodynamic model. This verified model can be used for the pathogen forecasting in the near-shore regions of southern Lake Michigan in the future.

关键词： near-shore channelized wind hydrodynamic model

Effect of changing the proportion of C16:0 and cis-9 C18:1 in fat supplements on rumen fermentation,glucose and lipid metabolism,antioxidation capacity,and visceral fatty acid profile in finishing Angus bulls

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Animal Nutrition 2024年第3期18卷 39-48页

作者： Haixin Bai lubo Wang Modinat Tolani Lambo Yang Li Yonggen Zhang College of Animal Science and Technology Northeast Agricultural UniversityHarbin 150030China

This study evaluated the effects of different proportions of palmitic(C16:0)and oleic(cis-9 C18:1)acids in fat supplements on rumen fermentation,glucose(GLU)and lipid metabolism,antioxidant function,and visceral fat fatty acid(FA)composition in Angus *** design of the experiment was a randomized block design with 3 treatments of 10 animals each.A total of 30 finishing Angus bulls(21±0.5 months)with an initial body weight of 626±69 kg were blocked by weight into 10 blocks,with 3 bulls per *** bulls in each block were randomly assigned to one of three experimental diets:(1)control diet without additional fat(CON),(2)CON+2.5%palmitic calcium salt(PA;90%C16:0),(3)CON+2.5%mixed FA calcium salts(MA;60%C16:0+30%cis-9 C18:1).Both fat supplements increased C18:0 and cis-9 C18:1 in visceral fat(P<0.05)and up-regulated the expression of liver FA transport protein 5(FATP5;P<0.001).PA increased the insulin concentration(P<0.001)and aspartate aminotransferase activity(AST;P=0.030)in bull's blood while reducing the GLU concentration(P=0.009).PA increased the content of triglycerides(TG;P=0.014)in the liver,the content of the C16:0 in visceral fat(P=0.004),and weight gain(P=0.032),and up-regulated the expression of liver diacylglycerol acyltransferase 2(DGAT2;P<0.001)and stearoyl-CoA desaturase 1(SCD1;P<0.05).MA increased plasma superoxide dismutase activity(SOD;P=0.011),reduced the concentration of acetate and total volatile FA(VFA)in rumen fluid(P<0.05),and tended to increase plasma non-esterified FA(NEFA;P=0.069)***,high C16:0 fat supplementation increased weight gain in Angus bulls and triggered the risk of fatty liver,insulin resistance,and reduced antioxidant *** adverse effects were alleviated by partially replacing C16:0 with cis-9 C18:1.

关键词： Palmitic acid Oleic acid Lipid metabolism Lipotoxicity Finishing bull

Deformation and Failure Mechanism of Phyllite under the Effects of THM Coupling and Unloading

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Journal of Mountain Science 2012年第6期9卷 788-797页

作者： MENG lubo LI Tianbin XU Jin CHEN Guoqing MA Hongming YIN Hongyu State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China School of Water Resources and Hydropower Sichuan UniversityChengdu 610065China

Although the study of TM(Thermo Mechanics),HM(Hydraulic-Mechanics) and THM(Thermo-Hydraulic-Mechanics) coupling under a loading test have been under development,rock failure analysis under THM coupling and unloading is an emerging *** on a high temperature triaxial unloading seep test for phyllite,this paper discusses the deformation and failure mechanism of phyllites under the "H M,T→H,T→M" incomplete coupling model with unloading *** results indicate that the elastic modulus and initial permeability decrease and the Poisson's ratio increases with increasing temperature;the elastic modulus decreases and the Poisson's ratio and initial permeability increase with increasing water *** the unloading process,rock penetrability is small at the initial elastic deformation phase,but the penetrability increases near the end of the elastic deformation phase;mechanisms involving temperature and water pressure affect penetrability *** failure occurs from the initial thermal damage of the rock materials,splitting and softening(which is caused by pore water pressure),and the pressure difference which is formed from the loading axial pressure and unloading confining *** phyllite failure mechanism is a transtensional(tension-shearing) failure.

关键词： Phyllite Mechanical characteristics Penetrability Failure mechanism Loading test Thermo-Hydraulic-Mechanics(THM)

Effect of natural and anthropogenic acidifi cation on aluminium distribution in forest soils of two regions in the Czech Republic

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Journal of Forestry Research 2021年第1期32卷 363-370页

作者： Lenka Pavlů lubošBorůvka Ondřej Drábek Antonín Nikodem Department of Soil Science and Soil Protection Faculty of AgrobiologyFood and Natural ResourcesCzech University of Life Sciences PraguePragueCzechia

To elucidate the dynamics of aluminium(Al),an element potentially toxic and strongly aff ected by acidifi cation processes,in soils,we selected two regions that were similar in relief,soil types,and vegetation cover but diff ered markedly in their history of acid precipitation:the JizerskéMountains(anthropogenically acidifi ed)and the NovohradskéMountains(naturally acidifi ed)in the Czech *** levels of Al forms(exchangeable and organically bound)associated with diff erent environmental impacts were measured and univalent,divalent and trivalent Al species were quantifi ed using HPLC/*** and organically bound Al concentrations were higher in the anthropogenically acidifi ed *** the concentrations of the leastdangerous species,the univalent,in organic soil horizons were similar for both *** concentrations of exchangeable Al forms were correlated with Ca concentrations and with pH in the organic *** known relationship of Al with soil pH was stronger in the mineral *** of exchangeable Al forms concentrations with sulphur concentrations or even more with the sulphur calcium molar ratio were found only in the JizerskéMountains,not in the Novohradské.Generally,the obtained results support the hypothesis that mechanisms diff ered between natural and anthropogenic acidifi cation.

关键词： Soil acidifi cation Spruce forest Soil properties Aluminium forms Aluminium species

Genomic signatures of selection,local adaptation and production type characterisation of East Adriatic sheep breeds

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Journal of Animal Science and Biotechnology 2024年第2期15卷 546-562页

作者： Boris Lukic Ino Curik Ivana Drzaic Vlatko Galić Mario Shihabi lubošVostry Vlatka Cubric-Curik Faculty of Agrobiotechnical Sciences Osijek J.JStrossmayer University of OsijekVladimira Preloga 131000 OsijekCroatia Department of Animal Science Faculty of AgricultureUniversity of ZagrebSvetošimunska Cesta 2510000 ZagrebCroatia Department of Maize Breeding and Genetics Agricultural Institute OsijekJužno predgrađe 1731000 OsijekCroatia Czech University of Life Sciences Prague Kamycka 12916500 PraqueCzech Republic

Background The importance of sheep breeding in the Mediterranean part of the eastern Adriatic has a long tradition since its arrival during the Neolithic *** production system is extensive and generally carried out in traditional systems without intensive systematic breeding programmes for high uniform trait production(carcass,wool and milk yield).Therefore,eight indigenous Croatian sheep breeds from eastern Adriatic treated here as metapopulation(EAS),are generally considered as multipurpose breeds(milk,meat and wool),not specialised for a particular type of production,but known for their robustness and resistance to certain environmental *** objective was to identify genomic regions and genes that exhibit patterns of positive selection signatures,decipher their biological and productive functionality,and provide a"genomic"characterization of EAS adaptation and determine its production *** We identified positive selection signatures in EAS using several methods based on reduced local variation,linkage disequilibrium and site frequency spectrum(eROHi,iHS,nSL and CLR).Our analyses identified numerous genomic regions and genes(e.g.,desmosomal cadherin and desmoglein gene families)associated with environmental adaptation and economically important *** candidate genes were related to meat/production and health/immune response traits,while some of the candidate genes discovered were important for domestication and evolutionary processes(e.g.,HOXa gene family and FSIP2).These results were also confirmed by GO and QTL enrichment *** Our results contribute to a better understanding of the unique adaptive genetic architecture of EAS and define its productive type,ultimately providing a new opportunity for future breeding *** the same time,the numerous genes identified will improve our understanding of ruminant(sheep)robustness and resistance in the harsh and specific Mediterranean environment.

关键词： Composite-likelihood ratio East Adriatic sheep Extreme ROH islands Genomic selection signatures Integrated haplotype score Number of segregating sites by length

Distribution law and susceptibility of geohazards across a gradient belt of the Western Sichuan Plateau

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Journal of Mountain Science 2024年第6期21卷 1849-1867页

作者： LI Tianbin WANG Jianfeng HE Chaoyang MENG lubo LI Chaofei MA Junjie WEI Daqiang College of Environment and Civil Engineering Chengdu University of TechnologyChengdu 610059China State Key Laboratory of Geohazard Prevention and Geo-environment Protection Chengdu University of TechnologyChengdu 610059China

Across a gradient belt of the Western Sichuan Plateau,geohazards have seriously limited economic and social *** to incomplete statistics,15,673 geohazards have been recorded in the study *** order to mitigate the threat of geohazards to human engineering activities in the region,an overall understanding of the distribution pattern of geohazards and susceptibility assessment are *** this paper,a gradient belt of the Western Sichuan Plateau and its zoning criteria were ***,on the basis of relief amplitude,distance to faults,rainfall,and human activities,three indicators of endogenic process were introduced:Bouguer gravity anomaly gradient,vertical deformation gradient,and horizontal deformation ***,the distribution patterns of geohazards were investigated through mathematical statistics and ArcGIS *** randomly selecting 10,449 hazards,a geohazard susceptibility map was generated using the Information Value(IV)***,the IV model was validated against 5224 hazards using the Area Under Curve(AUC)*** results show that 47.6%of the geohazards were distributed in the zone of steep *** showed strong responses to distance to faults,human activities,and annual *** distribution of geohazards in the gradient belt of the Western Sichuan Plateau is more sensitive to vertical internal dynamics factors(such as vertical deformation gradient and Bouguer gravity anomaly gradient)without any apparent sensitivity to horizontal internal dynamics *** areas of high and very-high risk account for up to 32.22%,mainly distributed in the Longmenshan and Anning River *** to the AUC plot,the success rate of the IV model for generating the susceptibility map is 76%.This susceptibility map and geohazard distribution pattern can provide a reference for geological disaster monitoring,preparation of post-disaster emergency measures,and town planning.

关键词： Gradient belt Geohazards Distribution law Bouguer Gravity anomaly gradient Vertical deformation gradient Susceptibility

A Physical Simulation Test for the RockBurst in Tunnels

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Journal of Mountain Science 2011年第2期8卷 278-285页

作者： LI Tianbin WANG Xiangfeng MENG lubo State Key Laboratory of Geohazard Prevention & Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China Sichuan Communication Surveying &Design Institute Chengdu 610017China

According to the test results of the physical and mechanical properties of similar materials in various quality mixture, a type of material with obvious tendency of rockburst was selected to produce a large-size model to simulate rockburst phenomena in tunnels. The prototype model comes from a typical section of diversion tunnels in Jinping Hydropower Station in China. The simulation of excavating tunnels is carried out by opening a hole in the model after loading. The modeling results indicated that under the condition of normal stresses in the model boundaries the arch top, spandrel and side walls of the tunnel produced an obvious jump reaction of stress and strain and the acoustic emission counts of the surrounding rock also increased rapidly in a different time period after the "tunnel" excavation, showing the clear features of rockburst. The spalling, buckling and breaking occurred in the surrounding rock of model in conditions of over loading. It is concluded that the modeling tunnel segment in Jinping Hydropower Station is expected to form the tensile rockburst with the pattern of spalling, buckling and breaking.

关键词： Rockburst Physical simulation Similar materials (Gypsum Cement Sand Water) Strain jump Spalling Buckling Breaking

Development of a New Polymercement Waterproofing Screed with Secondary Materials

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Journal of Civil Engineering and Architecture 2024年第2期18卷 80-85页

作者： lubošTaranza Faculty of Civil Engieneering Brno University of TechnologyBrno 60200Czech Republic

Throughout the world the issue of waste raw materials is still a very important *** paper is focused on the possibility of the use of waste raw material originated at high temperatures by the combustion of black coal as a partial substitution of filler component during the development of new waterproof levelling material designated for concrete *** use of the fly-ash as partial substitution of the filler component has important ecological and economic contribution.

关键词： Fly ash screed filler concrete