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Enhancing PIV image and fractal descriptor for velocity and shear stresses propagation around a circular pier

Geoscience Frontiers 2017年第4期8卷 869-883页

作者： Alireza Keshavarzi james ball Water Department Shiraz University School of Civil and Environmental Engineering University of Technology Sydney

In this study,the fractal dimensions of velocity fluctuations and the Reynolds shear stresses propagation for flow around a circular bridge pier are *** the study reported herein,the fractal dimension of velocity fluctuations（u′,v′,w′） and the Reynolds shear stresses（u′v′ and u′w′） of flow around a bridge pier were computed using a Fractal Interpolation Function（FIF） *** velocity fluctuations of flow along a horizontal plane above the bed were measured using Acoustic Doppler Velocity meter（ADV）and Particle Image Velocimetry（P1V）.The PIV is a powerful technique which enables us to attain high resolution spatial and temporal information of turbulent flow using instantaneous time *** this study,PIV was used for detection of high resolution fractal scaling around a bridge *** results showed that the fractal dimension of flow fluctuated significantly in the longitudinal and transverse directions in the vicinity of the *** was also found that the fractal dimension of velocity fluctuations and shear stresses increased rapidly at vicinity of pier at downstream whereas it remained approximately unchanged far downstream of the *** higher value of fractal dimension was found at a distance equal to one times of the pier diameter in the back of the ***,the average fractal dimension for the streamwise and transverse velocity fluctuations decreased from the centreline to the side wall of the ***,the results from ADV measurement were consistent with the result from PIV,therefore,the ADV enables to detect turbulent characteristics of flow around a circular bridge pier.

关键词： Fractal dimension Fractal interpolation function Fractal scaling Bridge pier Turbulent flow

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Experimental Study of the Effects of Submerged Dikes on the Energy and Momentum Coefficients in Compound Channel

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Engineering（科研） 2010年第11期2卷 855-862页

作者： Alireza Keshavarzi Mehdi Valizadeh james ball 不详

This paper aims to understand the flow structure around submerged dike in the main channel and flood plain of a compound cross section. The study undertaken to develop this understanding was carried out in a laboratory flume using a submerged vane installed at a 90 degree angle to the bank. In order to study the flow structures, the flow velocity was measured using a three-dimensional Acoustic Doppler Velocity meter (micro-ADV) with data collection rate of 50 Hz. These flow velocity measurements were taken at 500 points on a regular grid. As the tests were undertaken with turbulent flow, these conditions were subcritical. Furthermore, all the tests were undertaken using a fixed bed. The results obtained showed that the momentum transfer and the kinetic energy reduced in two directions. Also the energy and momentum coefficients decreased significantly with the installation of the submerged vane inside the main channel. Finally, streamlines were found to deviate from the side walls of channel into the main channel.

关键词： Submerged Vane Flow Structure Compound Channel Velocity Meter (Micro-ADV)

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Exposure of juvenile Chinook salmon to effluent from a large urban wastewater treatment *** *** responses

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Aquaculture and Fisheries 2024年第3期9卷 355-366页

作者： Suzanne C.ball james P.Meador C.Andrew james Jenifer K.McIntyre Washington State University School of the EnvironmentPuyallup Research and Extension Center2606 W Pioneer AvePuyallupWA98371USA Dept.of Environmental and Occupational Health Sciences School of Public Health4225 Roosevelt Way NESuite 100SeattleWA98105-6099USA University of Washington Tacoma Center for Urban Waters326 East D StreetTacomaWA98421-1801USA

Wastewater treatment plants release complex mixtures of chemicals into the aquatic environment as wastewater effluent(WWE);however,the effects of these mixtures are still poorly *** salmon(Oncorhynchus tshawytscha)are a culturally important species in the Pacific Northwest and are a vital food resource for southern resident killer whales(Orcinus orca)that are listed as‘critically endangered’under the *** Species Act(ESA).Chinook populations have declined drastically in this region and have failed to show significant recovery despite regional-to-federal efforts,resulting in many populations being listed as threatened under the *** source of stress to juvenile Chinook is chemical pollution from WWE during their outmigration along river corridors and residency in *** this study,we investigated effects of WWE on juvenile Chinook health in a ten-day exposure to dilutions of WWE from 0.1%to 20%.At the end of the exposure,we measured endpoints associated with endocrine disruption,brain function,osmoregulation,stress,and *** to WWE significantly(α=0.1 for all analyses)induced vitellogenesis,indicating endocrine system *** saw significant reductions in plasma glucose,an indication of stress,and brain Na+/K+-ATPase(NKA)activity,an enzyme essential for neuronal ***,metabolism was affected as evidenced by altered total protein,cholesterol,and albumin in plasma,a drastic decrease in whole body lipid content,and a significant increase in visible liver *** compared contaminant concentrations in exposure water with effects concentrations from the literature for chemicals known to induce vitellogenin or inhibit brain *** most contaminants,concentrations in exposure waters were several orders of magnitude below effects concentrations in the *** exception was estrogenic hormones,which were detected at similar concentrations in this study compared to concentrations in other studies tha

关键词： Wastewater effluent Chinook salmon Toxicity Sodium potassium ATPase Vitellogenin Physiology Metabolism Glucose

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Exposure of juvenile Chinook salmon to effluent from a large urban wastewater treatment *** *** profiling

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Aquaculture and Fisheries 2024年第3期9卷 367-377页

作者： james P.Meador Suzanne C.ball C.Andrew james Jenifer K.McIntyre Dept.of Environmental and Occupational Health Sciences School of Public Health4225 Roosevelt Way NESuite 100SeattleWA98105-6099USA Washington State University School of the EnvironmentPuyallup Research and Extension Center2606 W Pioneer AvePuyallupWA98371USA University of Washington Tacoma Center for Urban Waters326 East D StreetTacomaWA98421-1801USA

Targeted metabolomic analysis was conducted on juvenile Chinook salmon exposed for 10 days to wastewater effluent(WWE)from a large urban treatment *** included five dilutions of WWE(20%,5.3%,1.4%,0.4%,and 0.1%)and a control with 7 replicates per *** was extracted from fish and analyzed via liquid chromatography–mass spectrometry(LC-MS)for 361 endogenous metabolites,of which 185 were ***-versus-treatment comparisons identified several metabolites that were associated with altered biochemical pathways observed for all treatments,including several that are important for energy generation and *** altered pathways are crucial for fish health and may be an early indicator of potential adverse effects on growth,reproduction,behavior,and immune *** ocean-type Chinook salmon spend several days to weeks in the nearshore estuary where they may encounter high concentrations of WWE *** are exposed to a wide range of potent pharmaceuticals,personal care products,and industrial compounds from WWE that have the potential to affect physiological homeostasis and disrupt their normal life cycle.

关键词： Wastewater effluent Metabolomics Physiology Chinook salmon Pharmaceuticals Metabolic pathways Estuary

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Systematic Radio Telescope Alignment Using Portable Fringe Projection Profilometry

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Nanomanufacturing and Metrology 2024年第1期7卷 75-85页

作者： Joel Berkson Justin Hyatt Nathan Julicher Byeongjoon Jeong Isaac Pimienta Rachel ball Wyatt Ellis Jason Voris Diego Torres‑Barajas Daewook Kim james C.Wyant College of Optical Sciences University of Arizona1630 E.University Blvd.TucsonAZ 85721USA Department of Astronomy at Steward Observatory University of Arizona933 N Cherry Ave.TucsonAZ 85721USA

In 2019,the Event Horizon Telescope(EHT)released the first-ever image of a black hole event *** are now aiming for higher angular resolutions of distant targets,like black holes,to understand more about the fundamental laws of gravity that govern our *** achieve this higher resolution and increased sensitivity,larger radio telescopes are needed to operate at higher frequencies and in larger *** like the next-generation Very Large Array(ngVLA)and the Square-Kilometer Array(SKA)require building hundreds of telescopes with diameters greater than 10 ms over the next *** has a twofold *** telescope surfaces need to be more accurate to operate at higher frequencies,and the logistics involved in maintaining a radio telescope need to be simplified to support them properly in large *** of these problems can be solved with improved methods for surface metrology that are faster and more accurate with a higher *** leads to faster and more accurate panel alignment and,therefore,a more productive *** this paper,we present the use of binocular fringe projection profilometry as a solution to this problem and demonstrate it by aligning two panels on a 3-m radio telescope *** measurement takes only 10 min and directly delivers feedback on the tip,tilt,and piston of each panel to create the ideal reflector shape.

关键词： Metrology Fringe projection profilometry Off-axis alignment Radio astronomy Radio antenna

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Implementation of Envelope Analysis on a Wireless Condition Monitoring System for Bearing Fault Diagnosis

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International Journal of Automation and computing 2015年第1期12卷 14-24页

作者： Guo-Jin Feng james Gu Dong Zhen Mustafa Aliwan Feng-Shou Gu Andrew D.ball School of Computing and Engineering University of Huddersfield School of Engineering Manchester Metropolitan University

Envelope analysis is an effective method for characterizing impulsive vibrations in wired condition monitoring(CM)systems. This paper depicts the implementation of envelope analysis on a wireless sensor node for obtaining a more convenient and reliable CM system. To maintain CM performances under the constraints of resources available in the cost effective Zigbee based wireless sensor network(WSN), a low cost cortex-M4 F microcontroller is employed as the core processor to implement the envelope analysis algorithm on the sensor node. The on-chip 12 bit analog-to-digital converter(ADC) working at 10 k Hz sampling rate is adopted to acquire vibration signals measured by a wide frequency band piezoelectric accelerometer. The data processing flow inside the processor is optimized to satisfy the large memory usage in implementing fast Fourier transform(FFT) and Hilbert transform(HT). Thus, the envelope spectrum can be computed from a data frame of 2048 points to achieve a frequency resolution acceptable for identifying the characteristic frequencies of different bearing faults. Experimental evaluation results show that the embedded envelope analysis algorithm can successfully diagnose the simulated bearing faults and the data transmission throughput can be reduced by at least 95% per frame compared with that of the raw data, allowing a large number of sensor nodes to be deployed in the network for real time monitoring.

关键词： Wireless sensor network(WSN) envelope analysis fault diagnosis local processing Hilbert transformation

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Physical activity and dietary behaviors of health clinic workers trying to lose weight

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Health 2012年第8期4卷 493-499页

作者： Tan Leng Goh Trever ball Janet M. Shaw james C. Hannon Department of Exercise and Sport Science University of Utah Salt Lake City USA

Health clinic workers are potential agents of change for weight loss to patients, yet their behaviors are not well known. This study examined physical activity (PA) levels and dietary habits of health clinic workers who were and who were not trying to lose weight. Participants were 64 community health clinic workers (58 females and 6 males). Moderate-to-vigorous intensity (MVI) time spent in PA was assessed by triaxial accelerometry over 7 consecutive days. Dietary habits and weight loss efforts were determined by a food frequency questionnaire. Differences in MVI and nutrition variables were assessed by One-way ANOVA, comparing those trying to lose weight and those not trying to lose weight. 48 out of 64 health clinic workers (approximately 75%) indicated that they were currently trying to lose weight. There were significant differences (p < 0.05) in Body Mass Index (BMI), daily energy (Kcal) and fat (g) intake between those trying to lose weight and those not trying to lose weight. There were no significant differences in MVI, daily sugar intake (g), vegetable and fruit servings, and daily fiber intake (g) between groups. Health clinic workers trying to lose weight appear to be engaging in some appropriate dietary but not PA behaviors.

关键词： Accelerometer Overweight Healthcare Nutrition

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传染病学

传染病学

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2002年

作者：（英）Peter ball （英）james A.Gray 傅强主译

本书内容包括：儿童期常见传染病，巨细胞病毒感染，病毒性肝炎，猩红热，破伤风，病毒性脑膜炎，肺脓肿，抗生素药疹，艾滋病等。

关键词：传染病学科:诊疗

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Specific interaction of hepatitis C virus glycoproteins with mannan binding lectin inhibits virus entry

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Protein & Cell 2010年第7期1卷 664-674页

作者： Kristelle S.Brown Michael J.Keogh Ania M.Owsianka Richard Adair Arvind H.Patel james N.Arnold Jonathan K.ball Robert B.Sim Alexander W.Tarr Timothy P.Hickling Institute of Infection Immunity and InflammationSchool of Molecular Medical SciencesThe University of NottinghamQueen’s Medical CentreNottinghamNG72UHUK The Medical Research Council-University of Glasgow Centre for Virus Research University of GlasgowChurch StreetGlasgowG115JRUK MRC Immunochemistry Unit Department of BiochemistryUniversity of OxfordOX13QUUK Present address:Vitrology Biotech 5 South AvenueClydebank Business ParkGlasgowG812LGUK Present address:Pfizer Technologies Ltd. Ramsgate RoadSandwichKentCT139NJUK

Mannan-binding lectin(MBL)is a soluble innate immune protein that binds to glycosylated *** acts as an opsonin and activates complement,contributing to the destruction and clearance of infecting *** C virus(HCV)encodes two envelope glycoproteins E1 and E2,expressed as non-covalent E1/E2 heterodimers in the viral envelope.E1 and E2 are potential ligands for *** we describe an analysis of the interaction between HCV and MBL using recombinant soluble E2 ectodomain fragment,the full-length E1/E2 heterodimer,expressed in vitro,and assess the effect of this interaction on virus entry.A binding assay using antibody capture of full length E1/E2 heterodimers was used to demonstrate calcium dependent,saturating binding of MBL to HCV *** with various saccharides further confirmed that the interaction was via the lectin domain of *** binds to E1/E2 representing a broad range of virus *** was shown to neutralize the entry into Huh-7 cells of HCV pseudoparticles(HCVpp)bearing E1/E2 from a wide range of *** were neutralized to varying *** was also shown to neutralize an authentic cell culture infectious virus,strain JFH-1(HCVcc).Furthermore,binding of MBL to E1/E2 was able to activate the complement system via MBL-associated serine protease *** conclusion,MBL interacts directly with HCV glycoproteins,which are present on the surface of the virion,resulting in neutralization of HCV particles.

关键词： hepatitis C virus neutralization mannose binding lectin chronic viral infection

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Recording Africa: Charles ball's 1836 Narrative of Enslavement and Encounters

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Journal of Foreign Languages and Cultures 2020年第2期4卷 1-10页

作者： james McCorkle Hobart and William Smith Colleges

Charles ball's 1836 slave narrative is not only an example of an autobiographical narrative of escape from enslavement,it includes narratives of Africans who have been captured and brought to North ***'s narrative records the heterogeneity of Africans arriving-from Muslim West Africans to those from the Congo,a ubiquitous term given more specificity in his *** a distinction between an arrivant and someone,like himself,who may be a second generation enslaved person is ball's purpose,suggesting he belongs to a new ***’s descriptions parallel Zora Neale Hurston’s description of Kossola,a record of the last African brought to North America as an enslaved ***'s role recording his encounters parallels that of Hurston as ethnographer and *** as a social historian.

关键词： Charles ball Zora Neale Hurston Kossola W.E.B.Du Bois slavery Muslim environment

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