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A Strong Stability Preserving Analysis for Explicit Multistage Two-Derivative Time-Stepping Schemes Based on Taylor Series Conditions

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Communications on Applied Mathematics and Computation 2019年第1期1卷 21-59页

作者： Zachary Grant sigal Gottlieb David C.Seal Department of Computational and Applied Mathematics Oak Ridge National LaboratoryOak RidgeUSA Department of Mathematics University of Massachusetts DartmouthDartmouthUSA Department of Mathematics U.S.Naval AcademyAnnapolisUSA

High-order strong stability preserving(SSP)time discretizations are often needed to ensure the nonlinear(and sometimes non-inner-product)strong stability properties of spatial discretizations specially designed for the solution of hyperbolic ***-derivative time-stepping methods have recently been increasingly used for evolving hyperbolic PDEs,and the strong stability properties of these methods are of *** our prior work we explored time discretizations that preserve the strong stability properties of spatial discretizations coupled with forward Euler and a second-derivative ***,many spatial discretizations do not satisfy strong stability properties when coupled with this second-derivative formulation,but rather with a more natural Taylor series *** this work we demonstrate sufficient conditions for an explicit two-derivative multistage method to preserve the strong stability properties of spatial discretizations in a forward Euler and Taylor series *** call these strong stability preserving Taylor series(SSP-TS)*** also prove that the maximal order of SSP-TS methods is p=6,and define an optimization procedure that allows us to find such SSP *** types of these methods are presented and their efficiency ***,these methods are tested on several PDEs to demonstrate the benefit of SSP-TS methods,the need for the SSP property,and the sharpness of the SSP time-step in many cases.

关键词： Strong stability preserving Taylor series.Hyperbolic conservation laws Two derivative Runge Kutta

基于改进MSRCR的光伏板图像去雾方法研究

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长江信息通信 2024年第4期37卷 138-141页

作者：高航白晨博贾强西安石油大学陕西西安710065

针对光伏厂区遇到大雾天气,监控系统不能清晰观测到光伏板现场状况等问题,文章进行了图像去雾的算法研究,提出了一种改进的MSRCR算法,可以提高图像对比度和颜色饱和度,达到光伏板图像去雾的目的。以陕西某地为例,与两种传统算法进行比较... 详细信息

针对光伏厂区遇到大雾天气,监控系统不能清晰观测到光伏板现场状况等问题,文章进行了图像去雾的算法研究,提出了一种改进的MSRCR算法,可以提高图像对比度和颜色饱和度,达到光伏板图像去雾的目的。以陕西某地为例,与两种传统算法进行比较,结果表明,该文算法可以对光伏板带雾图像进行有效处理,获得更真实准确的细节和真实的光感色彩。

关键词：图像光伏板去雾 MSRCR

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Role of Dilatometrical Measurements in the Development of Multiphase Steels

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材料热处理学报 2004年第5期25卷 41-44页

作者： MártonTakács balázsVeroe ImreFelde JianshengPan BayZoltánInstituteofMaterialsScienceandTechnology BudapestHungary SchoolofMaterialsScienceandEngineeringShanghaiJiaoTongUniversity ShanghaiChina

Possibilities of means of dilatometry in connection with production of multiphase (DP- and TRIP-) steels were examined in detail. These steels are characterized by an excellent combination of high strength and good press formability, which are essentially important in the automotive industry. Transformation processes, cooling rates, holding temperatures, composition and technological parameters play a very important role in formation of applicable microstructure of multiphase steels. Dilatometrical experiments were carried out to study the processes of intercritical annealing and hot rolling of several DP- and TRIP-steels.

关键词：膨胀测定法多相钢相位变换模锻性

Mucosa-associated microbiota alterations in primary sclerosing cholangitis(PSC)before and after liver transplantation-who is calling the shots?

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Hepatobiliary Surgery and Nutrition 2023年第5期12卷 795-797页

作者： Münevver Demir Michael sigal Department of Hepatology and Gastroenterology Campus Virchow-Klinikum and Campus CharitéMitteCharitéUniversitätsmedizin BerlinBerlinGermany Berlin Institute for Medical Systems Biology Max Delbrück Center for Molecular MedicineBerlinGermany

Primary sclerosing cholangitis(PSC)is an immune-related chronic cholangiopathy associated with high rates of progression to liver cirrhosis and the need for liver *** PSC is frequently associated with inflammatory bowel disease(IBD),several studies have investigated the role of the gut-liver axis in PSC and emerging evidence indicates that gut and bile microbiota are associated with the onset and progression of PSC[reviewed in(1)].

关键词： Primary sclerosing cholangitis(PSC) liver transplantation Klebsiella microbiota mucosal microbiota

Sustainability of lime stabilized road subgrade in mountainous regions of Türkiye

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Journal of Mountain Science 2023年第8期20卷 2436-2452页

作者： Yavuz ABUT İlknur BOZBEY Ece KURT bal Department of Transportation Engineering Faculty of EngineeringYalova UniversityYalova 77200Türkiye Geotechnical Engineering Division Civil Engineering DepartmentAvcilar CampusIstanbul University-CerrahpasaAvcilar/Istanbul 34320Türkiye Civil Eng. M.Sc.&Geoph.Eng.Sentez Geopier FoundationsIstanbul 34320Türkiye

In this paper the use of lime stabilized subgrade for low volume roads in two regions with high mountains and different frost penetration conditions in Türkiye was investigated in terms of design,performance,and *** on unstabilized and stabilized subgrade were designed for two regions(Izmir and Van),covering all climate *** resilient modulus of the lime stabilized subgrade with different soil pulverization levels for non-freezing and freezing conditions were taken from a previous laboratory *** effects were considered in pavement design using two different approaches,including limited subgrade frost penetration method and reduced subgrade strength *** application and evaluation were performed for all *** stabilized subgrades significantly reduced the thickness of base courses,and the benefit of lime stabilization was highly dependent on soil pulverization level.A detailed cost analysis on the unstabilized and stabilized cases found that the use of lime stabilization in the subgrade provided significant initial cost *** analysis by using the AASHTO(1993)method and KENPAVE software,and quantity effect of soil pulverization level on the performance of low volume roads from a service life perspective,show that subgrade resilient modulus can be *** is also possible to make correct performance estimation in the *** results of the study show that lime stabilization is a good solution for low volume roads in the mountainous regions of Türkiye.

关键词： Aggregate Surfaced Roads Lime Stabilization Soil Pulverization Levels Road Design Service Life Cost analyses

Design and Development of a Wheel-less Snake Robot with Active Stiffness Control for Adaptive Pedal Wave Locomotion

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Journal of Bionic Engineering 2019年第4期16卷 593-607页

作者： Mohammadali Javaheri Koopaee Sander bal Christopher Pretty Xiaoqi Chen Mechanical Engineering Department University of CanterburyChristchurch 8041New Zealand Manufacturing Futures Research Institute Swinburne University of TechnologyHawthorn 3122Australia

This paper presents the design and manufacture process of a wheel-less,modular snake robot with series elastic actuators to reliably measure motor torque signal and investigate the effectiveness of active stiffness control for achieving adaptive snake-like locomotion.A polyurethane based elastic element to be attached between the motor and the links at each joint was designed and manufactured using water jet cutter,which makes the final design easier to develop and more cost-effective,compared to existing snake robots with torque measurement *** reliability of such torque measurement mechanism was examined using simulated dynamical model of pedal wave motion,which proves the efficacy of the design.A distributed control system was also designed,which with the help of an admittance controller,enables active control of the joint stiffness to achieve adaptive snake robot pedal wave locomotion to climb over obstacles,which unlike existing methods does not require prior information about the location of the *** effectiveness of the proposed controller in comparison to open-loop control strategy was verified by the number of *** results show the capability of the robot to successfully climb over obstacles with the height of more than 55%of the diameter of the snake robot modules.

关键词： modular snake robot series elastic actuator active stiffness control pedal wave locomotion adaptive locomotion

Effect of Ni^(7+) Ion Irradiation on Structure and Ammonia Sensing Properties of Thermally Oxidized Zinc and Indium Films

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Journal of Materials Science & Technology 2012年第8期28卷 700-706页

作者： Amandeep Kaur bal Rajinder Singh R.K.Bedi Material Science Laboratory Department of PhysicsGuru Nanak Dev University

ZnO and In203 films were prepared by thermal oxidation of vacuum deposited zinc and indium films, respec- tively onto the glass substrate at 30 ℃. The fabricated films have been irradiated with 100-MeV Ni7＋ ions at different fluences ranging from 5×1011 to 5×1013 ions/cm2. The structural and gas sensing properties of pristine and irradiated films have been discussed. X-ray diffraction （XRD） pattern of pristine and irradiated films reveal that the films are polycrystalline in nature and crystallinity increases after irradiation. In this study, highly porous In203 nanorods evolved when being irradiated at a fluence of 5×1013 ions/cm2 while ZnO film shows decrease in number of nanowires. The ammonia sensing performance of the Ni^7＋ irradiated In203 films shows an improvement as compared to its pristine counterpart.

关键词： Thermal oxidation ZnO film In203 film Ion irradiation Gas sensing

Changes of woody species diversity, horizontal and vertical distribution of stems across interior to outside within a primate rich habitat of Northeast India

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Journal of Forestry Research 2016年第4期27卷 787-798页

作者： Koushik Majumdar bal Krishan Choudhary Badal Kumar Datta Plant Taxonomy and Biodiversity Lab. Department of Botany Tripura University

The interior forest of protected area（PA）recover quickly in terms of greater diversity and structural complexity than peripheral and outsides, which may be due to high plant-frugivore interactions in the interior forest than the disturbed outsides. To describe the structural and functional differences in tree communities from interior to outside forests with in small PA, we quantitatively analyzed the vegetation of Trishna Wildlife Sanctuary, a rich primate habitat of Northeast India. Vegetation was sampled at C10 cm girth at breast height by 10 m 9 500 m sized20 line transects（10 ha） laid in the interior（N = 7）,peripheral（N = 7） and outside（N = 6） zones of this sanctuary. All transects were ordinated by Principal Component Analysis based on correlation between diversity and existing disturbance indices. We found significant differences（P ／ 0.05） in taxonomic richness and diversity indices between the habitat. Van diagram confirmed greater unique species richness in the interior zone（64） than peripheral（28） and outside（6） zones. Overall density（ha-1） did not differed across the zones, but basal area（m2ha-1） was significantly（P ／ 0.01） high in peripheral zone. Vertical distribution of stem density was linearly declined across zones（r2adj[ 0.70; P ／ 0.01） with increase in the canopy height. Horizontal distribution of adult stems showed significant inverse quadratic relationship（r2adj[ 0.80; P ／ 0.001）, which suggests very low density of canopy forming voluminous trees in the interior *** protection, restoration and management of interior regions are required to preserve local plant genetic diversity and also to maintain suitable habitat for threatened wildlife.

关键词： interior outside habitat restoration Northeast disturbance quickly inverse preserve quadratic

Prediction of the Resonance Characteristics of Combustion Chambers on the Basis of Large-Eddy Simulation

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Journal of Thermal Science 2005年第2期14卷 156-161页

作者： Franco MAGAGNATO balázs PRITZ Horst BCHNER Martin GABI Department of Fluid Machinery University of Karlsruhe GermanyDepartment of Fluid Machinery University of KarlsruheGermanyEngler-Bunte-Institute/Division for Combustion Technology University of KarlsruheGermanyDepartment of Fluid Machinery University of KarlsruheGermany

In the last few years intensive experimental investigations were performed at the University of Karlsruhe to develop an analytical model for the Helmholtz resonator-type combustion system. In the present work the resonance characteristics of a Helmholtz resonator-type combustion chamber were investigated using large-eddy simulations (LES), to understand better the flow effects in the chamber and to localize the dissipation. In this paper the results of the LES are presented, which show good agreement with the experiments. The comparison of the LES study with the experiments sheds light on the significant role of the wall roughness in the exhaust gas pipe.

关键词： compressible large-eddy simulation combustion instabilities oscillating flow damping ratio.