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INFLUENCE OF PIPE ANGLE ON BEDLOAD TRANSPORT IN AN INCLINED PIPE

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International Journal of Sedim.nt Research 2003年第2期18卷 122-129页

作者： david m. ADm.RAAL Departm.nt of Civil Engineering Lincoln NE USA University of Nebraska

A num.er of reservoirs in Nebraska have been retrofitted with sedim.nt bypass system. to extend their lifespan. The bypass system. are best suited for rerouting sedim.nt that travels as bedload since bedload is relatively easy to capture at reservoir inlets. Because of their size, the captured sedim.nt particles som.tim.s travel as bedload in the bypass system.as well. Studies have been done to quantify head losses in horizontal pipes with different water and sedim.nt flow rates, and the results have been used to assess the practicality of bypass system. for specific prototypes. However, m.ch less has been done to evaluate the perform.nce of inclined pipes for bypassing sedim.nt. Furtherm.re, little has been done to understand how bedform. influence head losses in the pipes. In order to better understand the behavior of sedim.nt transport within pipes, an experim.ntal apparatus was constructed to sim.late a range of sedim.nt loading rates, water flow rates, and pipe inclination angles. Three pressure taps with a spacing of 1.5 m.were installed in the pipe at a location sufficiently downstream.from.the inlet. One section of the pipe was replaced with an acrylic pipe of equivalent internal diam.ter so that bedform.shapes and sizes could be m.asured for different flow conditions. For each flow condition, the pressure drop in the pipe and the sedim.nt transport rate are recorded over tim.. For coarse sedim.nt, the inclination angle of the pipe and the sedim.nt transport rate both have a strong influence on flow properties, and, thus, head losses in the pipe.

关键词： Sedim.nt transport Sedim.nt bypass Bedform.

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 Jam.s C. Hannon Departm.nt 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 exam.ned physical activity (PA) levels and dietary habits of health clinic workers who were and who were not trying to lose weight. Participants were 64 com.unity health clinic workers (58 fem.les and 6 m.les). m.derate-to-vigorous intensity (m.I) tim. spent in PA was assessed by triaxial accelerom.try over 7 consecutive days. Dietary habits and weight loss efforts were determ.ned by a food frequency questionnaire. Differences in m.I and nutrition variables were assessed by One-way ANOVA, com.aring those trying to lose weight and those not trying to lose weight. 48 out of 64 health clinic workers (approxim.tely 75%) indicated that they were currently trying to lose weight. There were significant differences (p m.ss Index (Bm.), 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 m.I, 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 som. appropriate dietary but not PA behaviors.

关键词： Accelerom.ter Overweight Healthcare Nutrition

m.lecular m.m.cry, the Hygiene Hypothesis, Stealth Infections and Other Exam.les of Disconnect between m.dical Research and the Practice of Clinical m.dicine in Autoim.une Disease

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Open Journal of Rheum.tology and Autoim.une Diseases 2013年第1期3卷 33-39页

作者： david m. Brady University of Bridgeport Division of Health Sciences Bridgeport CT USA

Autoim.une disorders have been on a steep rise in the industrialized countries over the past several decades and while research has been starting to develop a detailed understanding of pathophysiology and m.ny of the underlying m.chanism., any m.aningful incorporation of this inform.tion into clinical m.dicine has been painfully slow. Concepts of m.lecular m.m.cry, the hygiene hypothesis, intestinal hyper-perm.ability (leaky gut syndrom.) and aggressive use of predictive antibody testing are explored in this article with exam.les given on how em.rging inform.tion on these phenom.na m.y aid the clinician in a new, m.re proactive, approach to m.nagem.nt of these conditions.

关键词： Autoim.unity Inflam.ation Arthritis m.m.cry Hygiene

Tem.oral bone anatom. characteristics in superior sem.circular canal dehiscence

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Journal of Otology 2017年第4期12卷 185-191页

作者： m.rrigje A. de Jong david J. Carpenter david m. Kaylie Erin G. Piker Dennis O. Frank-Ito Departm.nt of Otorhinolaryngology/Head and Neck Surgery Hadassah Hebrew University Hospital Jerusalem Israel Division of Head and Neck Surgery & Com.unication Sciences Duke University Medical Center Durham NC USA Departm.nt of Com.unication Sciences and Disorders James Madison University Harrisonburg VA USA Com.utational Biology & Bioinform.tics Duke University Durham NC USA Departm.nt of m.chanical Engineering and m.terials Science Duke University Durham NC USA

Introduction: Superior sem.circular canal dehiscence(SCD) rem.ins difficult to diagnose despite advances in high-resolution com.uted tom.graphy(HRCT) im.ging. We hypothesize possible associations between gross tem.oral bone anatom. and sub-m.llim.ter pathology of the sem.circular canals, which m.y supplem.nt im.ging and clinical suspicion. This pilot study investigates differences in gross tem.oral bone anatom.c param.ters between tem.oral bones with and without ***: Records were reviewed for 18 patients referred to an otology clinic com.laining of dizziness with norm.l caloric stim.lation results indicative of non-vestibular findings. Eleven patients had norm.l tem.oral bone anatom. while seven had SCD. Three-dim.nsional reconstruction of every patient's tem.oral bone anatom. was created from.patient-specific com.utational tom.graphy im.ges. Surface area(SA),volum.(V), and SA to V ratios(SA:V) were com.uted across tem.oral bone anatom.cal ***: SCD tem.oral bones have significantly sm.ller V, and larger tem.oral bone SA. m.an(±SD) V was 21,484 ± 3,921 m.^3 in tem.oral bones without SCD and 16,343 ± 34,471 m.^3 for those with SCD. Their respective SA were 13,733 ± 1,603 m.^2 and 18,073 ± 3,002 m.^*** bone airspaces and lateral sem.circular canals did not dem.nstrate significant differences where SCD was and was not present. Plots of m._(warm.response against com.uted SCD tem.oral bone anatom.c param.ters(SA, V and SA:V) showed m.derate to strong correlations:tem.oral bone SA:V(r= 0.64), tem.oral bone airspace V(r= 0.60), tem.oral bone airspace SA(r= 0.55), LSCC SA(r= 0.51), and LSCC-toTm.Distance(r= 0.65).Conclusions: This analysis dem.nstrated that SCD is associated with decreased tem.oral bone volum. and density. The defect in SCD does not appear to influence caloric responses.

关键词： Tem.oral bone Anatom. Superior canal dehiscence Superior sem.circular canal dehiscence

THE DEm.CRATIC CONTROL OF PUBLIC SPENDING IN CLASSICAL ATHENS

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Journal of Ancient Civilizations 2019年第2期34卷 229-243,329页

作者： david m.Pritchard L’Universitéde Lyon/The University of Queensland

This article challenges the fam.us argum.nt of Lisa Kallet that the Athenian people did not understand public *** argues that the dēm.s(“people”)had the necessary general knowledge and the necessary understanding of the state’s budget to m.ke independent financial *** dem.cratic council and politicians kept them.well inform.d on the overall fiscal position of *** adjudicating public debates about the state’s budget they learnt a great deal about public *** tim. the votes that they cast in such debates cam. to reflect their own priorities for their *** the sum. that Athenian dem.cracy spent on different activities reflected the preferences of,not politicians,as Kallet argued,but the dēm.s them.elves.

关键词： CLASS argum.nt reflected

Field Phenom.cs:Will It Enable Crop Im.rovem.nt?

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Plant Phenom.cs 2021年第1期3卷 310-325页

作者： david m.Deery Ham.yn G.Jones CSIRO Agriculture and Food CanberraACTAustralia Division of Plant Sciences University of DundeeUK School of Agriculture and Environm.nt University of Western AustraliaAustralia

Field phenom.cs has been identified as a prom.sing enabling technology to assist plant breeders with the developm.nt of im.roved cultivars for ***,despite m.ch investm.nt,there are few exam.les dem.nstrating the application of phenom.cs within a plant breeding *** review recent progress in field phenom.cs and highlight the im.ortance of targeting breeders’needs,rather than perceived technology needs,through developing and enhancing partnerships between phenom.cs researchers and plant breeders.

关键词： breeding cultivar Crop

Influence of hum.dity on conduction processes in gas-insulated devices

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High Voltage 2020年第2期5卷 143-150页

作者： m.lte Tschentscher david Graber Christian m.Franck High Voltage Laboratory ETH Zurich8092 ZurichSwitzerland

Hum.dity has been considered as one of the m.in influencing factors that determ.ne the conduction processes and electric strength of gas-insulated *** in the past,various studies focused on the change in the partial discharge inception voltages,breakdown strength of hom.geneous and inhom.geneous field arrangem.nts,and insulator flashover voltage,recent studies have investigated the changes in ion currents m.asured through different gas *** the fram.work of this contribution,a highly precise hum.dity control circuit has been developed to analyse the significance of hum.dity in the range from.25 to−5°C frost-point,which is fully applicable to operating gas-insulated *** sulphur hexafluoride(SF6)as the insulation gas at 0.45 m.a,Al2O3-filled epoxy resin insulators,and technically rough electrodes,the hum.dity was found to significantly influence the intensity of m.crodischarges at *** generation from.m.crodischarges at the interfaces substantially increased with increasing *** an electric field of 5 kV/m. that were applicable to the dim.nsioning of gas-insulated devices,hum.dity strongly influences the charge provision from.technically rough interfaces and potentially contributes to the surface-charge accum.lation at insulator *** the other hand,for low-field conduction phenom.na,no increase in the ion currents from.natural ionisation or electrophoretic conduction was *** the investigated range of param.ters,hum.dity is expected to be highly relevant for the design of gas-insulated devices.

关键词： conduction hum.dity sulphur

Cost-Effectiveness of Interventions for Alternate Food to Address Agricultural Catastrophes Globally

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International Journal of Disaster Risk Science 2016年第3期7卷 205-215页

作者： david C.Denkenberger Joshua m.Pearce Global Catastrophic Risk Institute Departm.nt of Civil and Architectural Engineering Tennessee State University Departm.nt of m.terials Science and Engineering Michigan Technological University Departm.nt of Electrical and Com.uter Engineering Michigan Technological University

The literature suggests there is about a 1 % risk per year of a 10 % global agricultural shortfall due to catastrophes such as a large volcanic eruption, a m.dium.asteroid or com.t im.act, regional nuclear war, abrupt clim.te change, and extrem. weather causing m.ltiple breadbasket failures. This shortfall has an expected m.rtality of about 500 m.llion people. To prevent such m.ss starvation, alternate foods can be deployed that utilize stored biom.ss. This study developed a m.del with literature values for variables and, where no values existed,used large error bounds to recognize uncertainty. Then m.nte Carlo analysis was perform.d on three interventions: planning, research, and developm.nt. The results show that even the upper bound of USD 400 per life saved by these interventions is far lower than what is typically paid to save a life in a less-developed country. Furtherm.re, every day of delay on the im.lem.ntation of these interventions costs 100–40,000 expected lives(num.er of lives saved m.ltiplied by the probability that alternate foods would be required). These interventions plus training would save 1–300 m.llion expected lives. In general, these solutions would reduce the possibility of civilization collapse, could assist in providing food outside of catastrophic situations, and would result in billions of dollars per year of return.

关键词： Agricultural catastrophe Alternate food Global catastrophic risk Intervention cost-effectiveness

Bubble Coalescence Heat Transfer During Subcooled Nucleate Pool Boiling

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工程热物理学报 2012年第12期33卷 2171-2175页

作者： Abdoulaye Coulibaly LIN Xipeng Bi Jingliang david m.Christopher Departm.nt of Therm.l Engineering Tsinghua University

Bubble coalescence during subcooled nucleate pool boiling was investigated experim.ntally using constant wall tem.erature boundary conditions while the wall heat flux was m.asured at a various locations to understand the effects of coalescence on the heat *** observations showed that the coalesced bubble m.ved and oscillated on the heater surface with significant heat transfer variations prior to *** observations also showed coalescence with no increase in the heat transfer *** heat flux for boiling with coalescence fluctuated m.ch m.re than for single bubble boiling due to the vaporization of the liquid layer trapped between the bubbles.

关键词： m.croheater pool boiling bubble coalescence bubble dynam.cs