检索结果-南通市图书馆

Rapid flood inundation mapping by differencing water indices from pre-and post-flood Landsat images

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Earth Science 2021年第1期15卷 1-11页

作者： Ramesh SIVANPILLAI Kevin m.jacobs Chloe m.mATTILIO Ela V.PISKORSKI Wyoming Geographic Information Science Center University of WyomingLaramieWY 82071USA Department of Ecosystem Science&management University of WyomingLaramieWY 82071USA Haub School of Environment&Natural Resources University of WyomingLaramieWY 82071USA Department of Plant Sciences University of WyomingLaramieWY 82071USA

Following flooding disasters,satellite images provide valuable information required for generating flood inundation *** or optical imagery can be used for generating flood maps when the inundated areas are not covered by *** propose a rapid mapping method for identifying inundated areas based on the increase in the water index value between the pre-and post-flood satellite *** of the Normalized Difference Water Index(NDWI)and modified NDWI(mNDWI)will be higher in the post-flood image for flooded areas compared to the pre-flood *** on a threshold value,pixels corresponding to the flooded areas can be separated from non-flooded *** maps derived from differencing mNDWI values accurately captured the flooded *** the output image will be influenced by the choice of the pre-flood image,hence analysts have to avoid selecting pre-flood images acquired in drought or earlier flood *** the inundation maps generated using this method have to be overlaid on the post-flood satellite image in order to orient personnel to landscape *** of the proposed technique are that flood impacted areas can be identified rapidly,and that the pre-existing water bodies can be excluded from the inundation *** pairs of other satellite data,several maps can be generated within a single flood which would enable emergency response agencies to focus on newly flooded areas.

关键词： Rapid Flood mapping(RFm) inundation maps Satellite data NDWI mNDWI

Disappearance and appearance of an indigestible marker in feces from growing pigs as affected by previous-and currentdiet composition

在线全文

学校读者我要写书评

暂无评论

Journal of Animal Science and Biotechnology 2017年第3期8卷 643-651页

作者： Brandy m.jacobs John F.Patience merlin D.Lindemann Kenneth J.Stalder Brian J.Kerr Department of Animal Science Iowa State UniversityAmes 50010USA Department of Animal and Food Sciences University of KentuckyLexington 40546KYUSA USDA-ARS-National Laboratory for Agricultural and the Environment Ames 50010IAUSA

Background： Indigestible markers are commonly utilized in digestion studies, but the complete disappearance or maximum appearance of a marker in feces can be affected by diet composition, feed intake, or an animal＇s *** objectives of this study were to determine the impact of previous（Phase 1, P1） and current-（Phase 2, P2）diet composition on marker disappearance（Cr） and appearance（Ti） in pigs fed 3 diets differing in NDF ***： When pigs were maintained on the 25.1, 72.5, and 125.0 g/kg NDF diets, it took 5.1, 4.1, and 2.5 d, respectively,for Cr levels to decrease below the limit of quantitation; or 4.6, 3.7, or 2.8 d, respectively, for Ti to be maximized. These effects were not, however, independent of the previous diet as indicated by the interaction between P1 and P2 diets on fecal marker concentrations（P 〈 0.01）. When dietary NDF increased from P1 to P2, it took less time for fecal Cr to decrease or fecal Ti to be maximized（an average of 2.5 d）, than if NDF decreased from P1 to P2 where it took longer for fecal Cr to decrease or fecal Ti to be maximized（an average of 3.4 d）.Conclusions： Because of the wide range in excretion times reported in the literature and improved laboratory methods for elemental detection, the data suggests that caution must be taken in considering dietary fiber concentrations of the past and currently fed diets so that no previous dietary marker addition remains in the digestive tract or feces such that a smal amount of maker is present to confound subsequent experimental results, and that marker concentration have stabilized when these samples are col ected.

关键词： Adaptation Digestibility Fiber Indigestible marker Pig

Color change in a marine isopod is adaptive in reducing predation

在线全文

学校读者我要写书评

暂无评论

Current Zoology 2015年第4期61卷 739-748页

作者： kristin m. HULTGREN Hannah mITTELSTAEDT Department of Biology Seattle University 901 12^th ave. Seattle WA 98122

Although background matching is a common form of camouflage across a wide diversity of animals, there has been surprisingly little experimental work testing the fitness consequences of this camouflage strategy, especially in marine ecosystems. In this study, we tested whether color camouflage enhances survival of the intertidal marine isopod Pentidotea （Idotea） wosnesenskii, quantified patterns of camouflage in different algal habitats, and examined how algal diet affected color change and growth using laboratory assays. In the field, isopods collected from two differently colored algal habitats （the brown alga Fucus distichus and the red alga Odonthaliafloccosa） matched the color of their respective algal habitats, and also differed significantly in body size： smaller red isopods were found on red algae, while larger brown isopods were found on brown algae. Predation ex- periments demonstrated these color differences had fitness benefits： brown isopods that matched their brown algae habitats sur- vived at higher rates than red unmatched isopods. Surprisingly, despite the propensity of isopods to match their algal habitats, algal diet had no effect on color change in color change experiments. Instead, isopods in all treatments turned browner, matching the color of the algal habitat that many isopods are found on as adults. In summary, our data supported our hypothesis that back- ground matching serves an adaptive function in reducing predation, with important evolutionary implications for explaining the wide variation in color change mechanisms in idoteid isopods [Current Zoology 61 （4）： 739-748, 2015].

关键词： Isopod Pentidotea wosnesenskii. Camouflage Crypsis Background matching Color change

modeling regional landslide susceptibility using dynamic soil moisture profiles

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of mountain Science 2018年第8期15卷 1807-1824页

作者： RAY Ram L jacobs Jennifer m DOUGLAS Ellen m Cooperative Agricultural Research Center College of Agriculture and Human Sciences Prairie View A&M University Department of Civil Engineering University of New Hampshire Environmental Earth and Ocean Sciences Department University of Massachusetts Boston

A landslide susceptibility mapping study was performed using dynamic hillslope hydrology. The modified infinite slope stability model that directly includes vadose zone soil moisture(Sm) was applied at Cleveland Corral, California, US and Krishnabhir, Dhading, Nepal. The variable infiltration capacity(VIC-3L) model simulated vadose zone soil moisture and the wetness index hydrologic model simulated groundwater(GW). The GW model predictions had a 75% NASH-Sutcliffe efficiency when compared to California's in-situ GW measurements. The model performed best during the wet season. Using predicted GW and VIC-3L vadose zone Sm, the developed landslide susceptibility maps showed very good agreement with mapped landslides at each study region. Previous quasi-dynamic model predictions of Nepal's hazardous areas during extreme rainfall events were enhanced to improve the spatial characterization and provide the timing of hazardous conditions.

关键词： Landslide susceptibility Vadose zone Soil moisture Infiltration eapacity VIC-3L Groundwater

Geochronological constraints on the metamorphic sole of the Semail ophiolite in the United Arab Emirates

在线全文

学校读者我要写书评

暂无评论

Geoscience Frontiers 2016年第4期7卷 609-619页

作者： Nick m.W.Roberts Robert J.Thomas Joachim.jacobs NERC Isotope Geosciences Laboratory British Geological SurveyKeyworthNG12 5GGUK Council for Geoscience P.O.Box 572Bellville 7535South Africa University of Bergen.Department of Earth Science PB 78035020 BergenNorway Norwegian Polar Institute Fram Centre9296 TromsoNorway

The Semail ophiolite of Oman and the United Arab Emirates （UAE） provides the best preserved large slice of oceanic lithosphere exposed on the continental crust, and offers unique opportunities to study processes of ocean crust formation, subduction initiation and obduction. metamorphic rocks exposed in the eastern UAE have traditionally been interpreted as a metamorphic sole to the Semail ophiolite. However, there has been some debate over the possibility that the exposures contain components of older Arabian continental crust. To help answer this question, presented here are new zircon and futile U-Pb geochronological data from various units of the metamorphic rocks. Zircon was absent in most samples. Those that yielded zircon and futile provide dominant single age populations that are 95-93 ma, partially overlapping with the known age of oceanic crust formation （96.5-94.5 ma）, and partially overlapping with cooling ages of the metamorphic rocks （95 90 ma）. The data are interpreted as dating high-grade metamorphism during subduction burial of the sediments into hot mantle lithosphere, and rapid cooling during their subsequent exhumation. A few discordant zircon ages, interpreted as late Neoproterozoic and younger, represent minor detrital input from the continent. No evidence is found in favour of the existence of older Arabian continental crust within the metamorphic rocks of the UAE.

关键词： Semail ophiolite United Arab Emirates metamorphic sole U-Pb geochronology Zircon Rutile

Does laser surface texturing really have a negative impact on the fatigue lifetime of mechanical components?

在线全文

学校读者我要写书评

暂无评论

Friction 2021年第6期9卷 1766-1775页

作者： Chia-Jui HSU Andreas STRATmANN Simon mEDINA Georg jacobs Frank mÜCKLICH Carsten GACHOT Institute for Engineering Design and Product Development TU WienLehárgasse 6Campus GetreidemarktVienna 1060Austria Chair of Functional materials Saarland UniversityCampus D3.3Saarbrücken 66123Germany AC2T Research GmbH Viktor-Kaplan-Straße 2/CWiener Neustadt 2700Austria Institute for machine Elements and Systems Engineering RWTH AachenSchinkelstraße 10Aachen 52062Germany

Laser surface texturing(LST)has been proven to improve the tribological performance of machine *** micro-scale patterns manufactured by LST may act as lubricant reservoirs,thus supplying oil when encountering insufficient ***,not many studies have investigated the use of LST in the boundary lubrication regime,likely due to concerns of higher contact stresses that can occur with the increasing surface *** study aims to examine the influence of LST on the fatigue lifetime of thrust rolling bearings under boundary lubrication.A series of periodic patterns were produced on the thrust rolling bearings,using two geometrically different designs,namely cross and dimple *** oil ISO VG 100 mixed with 0.05 wt%P of zinc dialkyldithiophosphate(ZDDP)was *** bearings with cross patterns reduce the wear loss by two orders of *** patterns not only retain lubricant in the textured pockets but also enhance the formation of an anti-wear *** tribofilm generation may be improved by the higher contact stresses that occur when using the textured ***,in contrast to the negative concerns,the ball bearings with cross patterns were instead found to increase the fatigue life by a factor of three.

关键词： thrust rolling bearing laser surface texturing direct laser interference patterning zinc dialkyldithiophosphate(ZDDP) tribofilm

Analytical evaluation of steady-state solute distribution in through- diffusion and membrane behavior test under non-perfectly flushing boundary conditions

在线全文

学校读者我要写书评

暂无评论

Journal of Rock mechanics and Geotechnical Engineering 2024年第1期16卷 258-267页

作者： Guannian Chen Yuchao Li kristin mSample-Lord Shan Tong School of Civil&Environmental Engineering and Geography Science Ningbo UniversityNingbo315211China mOE Key Laboratory of Soft Soils and Geoenvironmental Engineering College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou310058China Ningbo ZCONE High-tech Company Limited Ningbo315000China Department of Civil and Environmental Engineering Villanova UniversityVillanovaPAUSA

The through-diffusion and membrane behavior testing procedure using a closed-system apparatus has been widely used for concurrent measurement of diffusion and membrane efficiency coefficients of low-permeability clay-based barrier ***,the common assumption of perfectly flushing conditions at the specimen boundaries could induce errors in analyses of the diffusion coefficients and membrane *** this study,an innovative pseudo three-dimensional(3D)analytical method was proposed to evaluate solute distribution along the boundary surfaces of the soil-porous disks system,considering the non-perfectly flushing *** results were consistent with numerical models under two scenarios considering different inflow/outflow *** proposed model has been demonstrated to be an accurate and reliable method to estimate solute distributions along the *** calculated membrane efficiency coefficient and diffusion coefficient based on the proposed analytical method are more accurate,resulting in up to 50%less relative error than the traditional approach that adopts the arithmetic mean value of the influent and effluent *** retar-dation factor of the clay specimen also can be calculated with a revised cumulative mass ***,the simulated transient solute transport matched with experimental data from a multi-stage through-diffusion and membrane behavior test,validating the accuracy of the proposed method.

关键词： Diffusion testing membrane behavior Coupled transport Clay barrier Transport modeling

An improved symmetry-based approach to reciprocal space path selection in band structure calculations

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational materials 2020年第1期6卷 731-736页

作者： Jason m.munro Katherine Latimer matthew K.Horton Shyam Dwaraknath kristin A.Persson Energy Technologies Area Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA Department of Physics University of CaliforniaBerkeleyCA 94720USA Department of materials Science University of CaliforniaBerkeleyCA 94720USA

Band structures for electrons,phonons,and other quasiparticles are often an important aspect of describing the physical properties of periodic *** commonly,energy bands are computed along a one-dimensional path of high-symmetry points and line segments in reciprocal space(the“k-path”),which are assumed to pass through important features of the dispersion ***,existing methods for choosing this path rely on tabulated lists of high-symmetry points and line segments in the first Brillouin zone,determined using different symmetry criteria and unit cell *** we present a new“on-the-fly”symmetry-based approach to obtaining paths in reciprocal space that attempts to address the previous limitations of these *** a unit cell of a magnetic or nonmagnetic periodic solid,the site symmetry groups of points and line segments in the irreducible Brillouin zone are obtained from the total space *** elements in these groups are used alongside general and maximally inclusive high-symmetry criteria to choose segments for the final k-path.A smooth path connecting each segment is obtained using graph *** new framework not only allows for increased flexibility and user convenience but also identifies notable overlooked features in certain electronic band *** addition,a more intelligent and efficient method for analyzing magnetic materials is also enabled through proper accommodation of magnetic symmetry.

关键词： symmetry reciprocal approach

Longitudinal changes in cardiac function in the very elderly: the Jerusalem longitudinal cohort study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Geriatric Cardiology 2019年第11期16卷 800-805页

作者： David Leibowitz Irit Stessman-Lande Hend Sliman Jeremy m.jacobs Jochanan Stessman Dan Gilon Jerusalem Institute of Aging Research Hadassah-Hebrew University Medical CenterMount-ScopusJerusalemIsrael Coronary Care Unit Hadassah–Hebrew University Medical CenterMount-ScopusJerusalemIsrael Department of Geriatrics and Rehabilitation Hadassah-Hebrew University Medical CenterMount-ScopusJerusalemIsrael

Background People over the age of 85 are a rapidly growing age group with a high incidence of congestive heart failure(CHF),in particular heart failure with preserved ejection fraction(HFp EF).The diagnosis of CHF is challenging and longitudinal data assessing cardiac structure and function are necessary to distinguish physiologic from pathologic cardiac *** objective of the study was to determine longitudinal changes in cardiac struture and function from ages 85 to 94 years using home *** Subjects were recruited from the Jerusalem Longitudinal Cohort *** three members of the initial cohort(32 F,31 m)who underwent home echocardiography at age 85 were the subjects of the current study and underwent repeat home 2-D and Doppler echocardiographic assessment at age *** There were no significant longitudinal changes in left ventricular mass index(LVmI),however LV end-diastolic volume significantly decreased from 113.4±30 to 103.6±35.5 m L(Pmained stable,however longitudinal systolic function significantly decreased with age from 7.9±1.8 to 6.6±1.4 cm/s2(Pme index(34.1±11.3 to 42.4±13.7 m L/m^2,Pmonstrated preserved EF with decreased longitudinal systolic function and diastolic function without significant change in LV *** in LV function in the very elderly may be independent of changes in LV geometry.

关键词： Echocardiography The elderly Ventricular function