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Scour depth beneath a pipeline undergoing forced vibration

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Theoretical & Applied Mechanics Letters 2015年第2期5卷 97-100页

作者： Y.Luan D.Liang R.Rana Department of Engineering University of Cambridge MOE Key Laboratory of Hydrodynamics Shanghai Jiao Tong University school of business and Economics Loughborough University State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

This paper studies the coupling effect of the pipeline vibration on the seabed scour. A vertical two- dimensional model is applied to numerically investigate the local scour below a vibrating pipeline with different amplitudes and periods. Using the scour underneath a fixed pipeline as a reference, this paper focuses on the impact of the pipeline vibration on the equilibrium scour depth. Generic relationships are established between the non-dimensional scour depth and the non-dimensional vibrating parameters, i.e., amplitude and frequency. The normalization process takes into account the influences of such parameters as the incoming flow velocity, pipe diameter, and Shields parameter. An empirical formula is proposed to quantify these relationships.

关键词： Offshore pipelines Scour Numerical models Vibration Sediment transport

Water resource forecasting with machine learning and deep learning:A scientometric analysis

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Artificial Intelligence in Geosciences 2024年第1期5卷 220-231页

作者： Chanjuan Liu Jing Xu Xi’an Li Zhongyao Yu Jinran Wu school of business Administration and Customs Shanghai Customs CollegeShanghai 201204PR China College of Hydraulic Science and Engineering Yangzhou UniversityYangzhou 225009PR China Ceyear Technologies Co. Ltd.Qingdao 266555PR China The Institute for Positive Psychology and Education Australian Catholic UniversityBanyo 4014Australia

Water prediction plays a crucial role in modern-day water resource management,encompassing both logical hydro-patterns and demand *** gain insights into its current focus,status,and emerging themes,this study analyzed 876 articles published between 2015 and 2022,retrieved from the Web of Science *** CiteSpace visualization software,bibliometric techniques,and literature review methodologies,the investigation identified essential literature related to water prediction using machine learning and deep learning *** a comprehensive analysis,the study identified significant countries,institutions,authors,journals,and keywords in this *** exploring this data,the research mapped out prevailing trends and cutting-edge areas,providing valuable insights for researchers and practitioners involved in water prediction through machine learning and deep *** study aims to guide future inquiries by highlighting key research domains and emerging areas of interest.

关键词： Water forecasting Machine learning/deep learning Web of Science Visualization

TROPICAL VERTICAL GREENERY SYSTEMS:IRRIGATION SYSTEMS,BIOPHYSICAL CHARACTERISTICS,AND INFLUENTIAL CIRTERIA

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Journal of Green Building 2016年第4期11卷 57-90页

作者： Chen Wang Lincoln C.Wood Li Tien Teo College of Civil Engineering Huaqiao UniversityXiamen361021P.R.China Faculty of business and Law Auckland University of TechnologyPrivate Bag 92006Auckland 1142New Zealand school of Information Systems Curtin UniversityPerthAustralia Faculty of Built Environment University of Malaya50603Kuala LumpurMalaysia

Recent studies on vertical greenery systems(VGS)mainly focus on thermal perfor-mance,acoustics effects,energy savings and environmental *** are very few studies on tropical VGS irrigation systems,plants’characteristics,and favor-able installation locations,indicating that architectural professionals may lack suffi-cient guidance to support their design *** two descriptive case studies and a questionnaire survey of VGS-related professionals including gardeners,mechanical and electrical engineers,consultants,contractors,and developers,this research devel-oped a knowledgebase for tropical vertical greenery systems irrigation systems and determined the suitability of different types of vertical greenery systems according to the biophysical characteristics of *** suitability for various plant character-istics has been identified to help potential users while considering vertical greenery systems irrigation *** locations,orientations and microclimatic condi-tions for vertical greenery systems irrigation systems to prevent system failure have been *** research focused on establishing the technical requirements for irrigation scheduling is recommended to improve the application efficiency.

关键词： Vertical Greenery System(VGS) irrigation system building vegetation green facades tropics survey

Promoted catalytic property of Cu/SSZ-13 by introducing a minority of Mn for NO removal from diesel engine exhaust

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Chinese Journal of Chemical Engineering 2024年第7期71卷 172-182页

作者： Runnong Yang Wuyuan Liu Zhaoying Wang Ming Sun Guangying Fu Zihan Gao Wenjian Jiao Rui Li Lin Yu Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center Jieyang 515200China Guangdong Engineering Technology Research Center of Modern Fine Chemical Engineering School of Chemical Engineering and Light IndustryGuangdong University of TechnologyGuangzhou 510006China Key Laboratory of Bioinorganic and Synthetic Chemistry School of ChemistrySun Yat-sen UniversityGuangzhou 510275China Testing and Certification business Department China Automotive Technology and Research Center Company LimitedWuhan 430056China Guangdong Foran Technology Company Limited Foshan 528000China

The Cu-exchanged SSZ-13 with the small-pore chabazite framework is considered as a highly efficient catalyst for selective catalytic reduction of NO with NH_(3)(NH_(3)-SCR).In order to further improve the catalytic property,a series of Mn ion-assisted Cu/SSZ-13 powder catalysts were prepared by co-exchange method and stepwise exchange *** is found that the NH_(3)-SCR activity,N_(2) selectivity,hydrothermal stability and sulfur resistance of Cu/SSZ-13 are promoted by introducing a minority of Mn(0.15%to 0.23%(mass))through co-exchange *** results reveal that the Cu,Mn co-exchange enables the higher amounts of Cu^(2+)active sites,the abundant medium strong and strong acid,the optimized ratio of Lewis acid to Brønsted acid etc.,which are required for a good NH_(3)-SCR catalytic property over broad temperature range and under harsh working ***,a monolithic catalyst was prepared by impregnating a cordierite ceramic support into the coating slurry containing the optimized CuMn/SSZ-13 *** diesel engine bench tests show that Cu,Mn co-exchange gives the monolith catalyst a better catalytic property than commercial *** work provides an important guidance for the rational design of secondary-ion-assisted zeolites applied in NH_(3)-SCR.

关键词： MnCu/SSZ-13 Co-exchange Zeolite Catalysis Selective catalytic reduction

An Integrated Observer Framework Based Mechanical Parameters Identification for Adaptive Control of Permanent Magnet Synchronous Motor

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Complex System Modeling and Simulation 2022年第4期2卷 354-367页

作者： Zhong Liao Zhaohua Liu Lei Chen Mingyang Lyu Dian Wang Faming Wu Zhengheng Wang Hualiang Wei the school of Information and Electrical Engineering Hunan University of Science and TechnologyXiangtan 411201China the Wind Power business Division CRRC Zhuzhou Institute Co.Ltd.Zhuzhou 412001China. the Department of Automatic Control and Systems Engineering University of SheffieldSheffieldS13JDUK.

An integrated observer framework based mechanical parameters identification approach for adaptive control of permanent magnet synchronous motors is proposed in this ***,an integrated observer framework is established for mechanical parameters’estimation,which consists of an extended sliding mode observer(ESMO)and a Luenberger *** at minimizing the influence of parameters coupling,the viscous friction and the moment of inertia are obtained by ESMO and the load torque is identified by Luenberger observer *** obtaining estimates of the mechanical parameters,the optimal proportional integral(PI)parameters of the speed-loop are determined according to third-order best design *** a result,the controller can adjust the PI parameters in real time according to the parameter changes to realize the adaptive control of the ***,the disturbance is compensated according to the ***,the experiments were carried out on simulation platform,and the experimental results validated the reliability of parameter identification and the efficiency of the adaptive control strategy presented in this paper.

关键词： parameter identification permanent magnet synchronous motor adaptive control extended sliding mode observer Luenberger observer

Responses to oral glucose challenge differ by physical activity volume and intensity: A pilot study

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Journal of Sport and Health Science 2020年第6期9卷 645-650页

作者： Trevor N.Simper Cecile Morris Anthony Lynn Ciara O’Hagan Karen Kilner Food Group Sheffield business school Sheffield Hallam UniversitySheffield S11WBUK Academy of Sport and Physical Activity Sheffield Hallam UniversitySheffield S102BPUK Department for Health and Social Care Research Sheffield Hallam UniversitySheffield S102BPUK

Background:One-hour postprandial hyperglycemia is associated with increased risk of type 2 diabetes and cardiovascular *** activity(PA)has short-term beneficial effects on post-meal glucose *** study compared the oral glucose tolerance test results of 3 groups of people with habitually different levels of ***:Thirty-one adults without diabetes(age 25.9±6.6 years;body mass index 23.8±3.8 kg/m^2;mean±SD)were recruited and divided into 3 groups based on self-reported PA volume and intensity:low activity0.05).The groups were significantly different in terms of baseline glucose level(p=0.003)and,marginally,for gender(p=0.053)and BMI(p=0.050).There was a statistically significant effect of PA on the 1-h postprandial glucose results(p=0.029),with differences between very active and low activity groups(p=0.008)but not between the moderately active and low activity groups(p=0.360),even when baseline glucose level and gender differences were accounted *** incremental area under the curve there was no significant effect of activity group once gender and body fat percentage had been accounted for(p=0.401).Those in the low activity group took 15 min longer to reach peak glucose level than those in the very active group(p=0.012).Conclusion:The results suggest that high levels of PA have a beneficial effect on postprandial blood glucose profiles when compared to low and moderate levels of activity.

关键词： Blood glucose response Incremental area under the curve Oral glucose tolerance test Physical activity Time to peak Type 2 diabetes

A Stage-Structured Predator-Prey System with Impulsive Effect and Holling Type-Ⅱ Functional Response

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Journal of Mathematical Research and Exposition 2011年第1期31卷 147-156页

作者： Ling Shu WANG Rui XU Guang Hui FENG school of Mathematics and Statistics Hebei University of Economics & Business Shijiazhuang 050061 P. R. China Institute of Applied Mathematics Shijiazhuang Mechanical Engineering College Shijiazhuang 050003 P. R. China

A stage-structured predator-prey system with impulsive effect and Holling type-II functional response is investigated. By the Floquet theory and small amplitude perturbation skills, it is proved that there exists a global stable pest-eradication periodic solution when the impulsive period is less than some critical values. Farther, the conditions for the permanence of system are established. Numerical simulations are carried out to illustrate the impulsive effect on the dynamics of the system.

关键词： predator-prey system Holling type-II functional response impulsive effect extinction permanence.

Demographic and socioeconomic determinants of urinary arsenic concentration for elementary school children in Bangladesh

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Global Health Journal 2024年第3期8卷 119-127页

作者： Raisa Sara Khalid M.Khan Shelbin Mattathil Munachimso Nwankwo Mohammad Aminul Islam Faruque Parvez Department of Economics and International business College of Business AdministrationSam Houston State UniversityHuntsvilleTX 77340USA Department of Public Health College of Health SciencesSam Houston State UniversityHuntsvilleTX 77340USA College of Osteopathic Medicine Sam Houston State UniversityConroeTX 77304USA Paul G.Allen school for Global Health Washington State UniversityPullmanWA 99164USA Department of Environmental Health Mailman School of Public HealthColumbia UniversityNew YorkNY 10032USA

Background:Arsenic(As)is a toxic element that can lead to various health issues in *** primary exposure to As is through the consumption of water contaminated with high As levels,particularly in *** studies have shown that urinary arsenic(UAs)concentration can reflect As exposure and metabolism in ***,little is known about how other factors,such as age,sex,and socioeconomic status,may affect UAs concentrations in ***:This study aimed to investigate the influence of factors such as age,sex,and socioeconomic status on UAs concentrations in children,in addition to the impact of drinking water arsenic(WAs)***:We conducted our study on elementary school-going children aged 8-11 years from rural Araihazar in *** measured UAs(available for a subset of 391 children)and WAs levels and collected information on demographic and socioeconomic *** employed regression analysis and t-tests to analyze the ***:Our findings revealed that younger children(β=197.95,95%confidence interval[CI]:111.97 to 283.94),female children(β=93.95,95%CI:8.49 to 179.40),and children with less educated fathers(β=138.03,95%CI:26.47 to 249.58)had higher UAs levels,particularly when they consumed water with high As ***:The study concludes that children's As exposure and UAs concentration may vary depending on their age,sex,and socioeconomic ***,these factors should be considered when assessing the health risks associated with As.

关键词： Waterarsenic Rural children Socioeconomicfactors Bangladesh

Dehydration, hydrolysis and oxidation of cerium chloride heptahydrate in air atmosphere

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Journal of Rare Earths 2017年第11期35卷 1156-1163页

作者： Shoufeng Xue Wenyuan Wu Xue Bian Yongfu Wu Metallurgy school of Northeastern University Shenyang 110819 PR China school of Energy and Environmental Engineering Inner Mongolia University of Science and Technology Baotou 014010 PR China

The thermal decomposition of CeCl3·7 H2O was studied from room temperature to 800 ℃. Analysis was performed by applying TG-DTA, XRD, FESEM, EDXS, and TG-MS technologies to investigate the thermal decomposition mechanism of CeCl3·7 H2O in air atmosphere. Multiple forms of hydrated cerium chloride compound were observed in the dehydration products. The CeCl3hydrolysis product was separated by a continuous centrifugation method and the phase composition was identified as CeO2,Ce(OH)3,and CeCl3·4 H2O by XRD analysis. The evolved gas composition was identified as CI2and HCI by TG-MS system. Based on the analysis of the experimental results, the mechanism of thermal decomposition of CeCl3·7 H2O was proposed with completion of the dehydration reaction at 224 ℃,the hydrolysis reaction at 170-480 ℃,and the oxidation reaction of CeCl3above 480 ℃.

关键词： CeCl_3 Hydrolysis Oxidation XRD MS