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Accounting for the Effects of Climate Variability in Regional Flood Frequency Estimates in Western Nigeria

Journal of Water Resource and Protection 2020年第8期12卷 690-713页

作者： Iguniwari Thomas Ekeu-Wei george alan blackburn Jason Giovannettone Lancaster Environmental Centre Lancaster University Lancaster UK Kawari Technical Services Nigeria Limited Yenagoa Nigeria Dewberry 8401 Arlington Blvd. Fairfax Virginia USA

Extreme flood events are becoming more frequent and intense in recent times, owing to climate change and other anthropogenic factors. Nigeria, the case-study for this research experiences recurrent flooding, with the most disastrous being the 2012 flood event that resulted in unprecedented damage to infrastructure, displacement of people, socio-economic disruption, and loss of lives. To mitigate and minimize the impact of such floods now and in the future, effective planning is required, underpinned by analytics based on reliable data and information. Such data are seldom available in many developing regions, owing to financial, technical, and organizational drawbacks that result in short-length and inadequate historical data that are prone to uncertainties if directly applied for flood frequency estimation. This study applies regional Flood Frequency Analysis (FFA) to curtail deficiencies in historical data, by agglomerating data from various sites with similar hydro-geomorphological characteristics and is governed by a similar probability distribution, differing only by an “index-flood”;as well as accounting for climate variability effect. Data from 17 gauging stations within the Ogun-Osun River Basin in Western Nigeria were analysed, resulting in the delineation of 3 sub-regions, of which 2 were homogeneous and 1 heterogeneous. The Generalized Logistic distribution was fitted to the annual maximum flood series for the 2 homogeneous regions to estimate flood magnitudes and the probability of occurrence while accounting for climate variability. The influence of climate variability on flood estimates in the region was linked to the Madden-Julian Oscillation (MJO) climate indices and resulted in increased flood magnitude for regional and direct flood frequency estimates varying from 0% - 35% and demonstrate that multi-decadal changes in atmospheric conditions influence both small and large floods. The results reveal the value of considering climate variability for fl

关键词： Climate Variability Regional Flood Frequency Climate-Indices L-Moment Madden-Julian Oscillation (MJO) Generalised Logistic (GLO) Climate-Indices

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Understanding the multi-seasonal spectral and biophysical characteristics of reedbed habitats in the UK

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Geo-Spatial Information Science 2016年第4期19卷 233-244页

作者： Alex O.Onojeghuo george A.blackburn Department of Surveying and Geoinformatics Nnamdi Azikiwe UniversityAwkaNigeria Lancaster Environment Centre Lancaster UniversityLancasterUK

Reedbed in the UK has been classified as priority habitat for most regional Biodiversity ***,critical information pertaining to the quality and spatial coverage of reedbed is currently *** paper presents the results of a project conducted in collaboration with the Cumbria Wildlife Trust and Environment Agency aimed at monitoring and understanding variations in the spectral reflectance and biophysical properties of reedbed canopies across Leighton Moss Nature Reserve in Lancashire,northwest *** the seasonal phenological cycle of the reedbed habitats in the study area,optimal spectral indices required for quantifying its biophysical properties were determined using field spectroscopy and ground-based *** of the experiment showed that the narrow-bandderived Difference Vegetation Index(DVI)and Renormalised Difference Vegetation Index(RDVI),with the correlation coefficient R2 of 0.77 and 0.72,respectively,provided the most accurate estimates of the leaf area index for the reedbed canopies.

关键词： Vegetation index leaf area index biophysical measures

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Amplitude-mode spectroscopy of chemically injected and photogenerated charge carriers in semiconducting single-walled carbon nanotubes

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Nano Research 2023年第4期16卷 5619-5625页

作者： Shai R。Vardeny alan Phillips Kira A。Thurman ZValy Vardeny Jeffrey L.blackburn Division of Electrical Electronicand Infocommunications EngineeringOsaka University2-1 Yamada-okaSuitaOsaka 565-0871Japan Materials Chemistryand Computation Science DirectorateNational Renewable Energy LaboratoryGoldenCO 80401USA Department of Physics Colorado School of MinesGoldenCO 80401USA Department of Physics&Astronomy University of UtahSalt Lake CityUT 84112USA

In one-dimensional semiconductors such as conjugated polymers and semiconducting single-walled carbon nanotubes(s-SWCNTs),injected charge carriers(electrons or holes)can have profound impacts on both electronic conductivity and optical spectra,even at low carrier *** charge-related spectral features is a key fundamental challenge with important technological ***,we employ a systematic suite of experimental and theoretical tools to understand the mid-infrared charge signatures of heavily p-type doped polymer-wrapped *** a broad range of nanotube diameters,we find that hole charge carriers induce strong Fano anti-resonances in mid-infrared transmission spectra that correspond to defect-related(D-band)and in-plane tangential(G-band)Raman-active vibrational modes,along with antiresonances arising from infrared(IR)-active polymer and SWCNT *** employ^(13)C isotope-labeled s-SWCNTs and a removable wrapping polymer to clarify the relative intensities,energies,and sources of all observed *** performed with the“amplitude mode model”are used to quantitatively reproduce Raman spectra and also help to explain the outsized intensity of the D-band anti-resonance,relative to the G-band,observed for both moderately and degenerately doped *** results provide a framework for future studies of ground-and excited-state charge carriers in s-SWCNTs and a variety of low-dimensional materials.

关键词： carbon nanotubes doping charge carriers phonons electron-phonon coupling

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Metal affinities in single and multiple ion adsorption reaction at sulfide mineral surfaces

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Journal of Environmental Sciences 1989年第1期1卷 15-30页

作者： george W.Bailey alan T.Lynch Environmental Research Laboratory Office of Research and Development U.S. EPA Athens Georgia 30613 U.S.A.Technology Applications Inc. Athens Georgia 30613 U.S.A.

Sulfide minerals are found in porous media in both aerobic and anaerobic environments, they should have a high affinities for certain metals. The relative binding affinities and reaction processes for 10 metal/metalloid ions reacting with four sulfide mineral surfaces has been *** order of reactivity is chalcocite > pyrite > galena >> sphalerite. For any particular metal and mineral, the greater reactivity occurs in the single-ion metal system except Ag(I) on pyrite and Cu(II) on *** precipitation and adsorption reaction can decrease metal ion mobility on porous media, the order of metal mobility in the presence of the four sulfide minerals is predicted to be: Zn(II), Cd(II) and Ni(II) - mobile; Cu(II), Pb(II), Fe(III), As(III) and Cr(III) - variable mobility and Ag(I) - ***1 predictions on metal phase distribution / partitioning compared quite well with those observed experimentally. Solubility product considerations, intrinsic acidity constant of the mineral, EH, pH and the carbonate equilibrium are major factors controlling the phase distribution of metals reacting singularly or in combination with sulfide mineral surfaces.

关键词： metal affinities sulfide mineral adsorption MINTEQA1 model reduction.

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Adsorption and desorption of lanthanum at sulfide mineral surface

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Journal of Environmental Sciences 1990年第3期2卷 51-66页

作者： george W.Bailey alan T.Lynch Environmental Research Laboratory Office of Research and Development U. S. Environmental Protection Agency Athens Georgia 30613.Technology Applications Inc. Athens Georgic 30613.

Batch adsorption experiment with four sulfide minerals - Chalcocite galena, pyrite and sphalerite - were used to study for the adsorption and desorp-tion behavior of La (III) in the presence of EDTA, a model humic matter. Linear adsorption was found in all *** presence of soluble organic complexing ligand should reduce the mobility of La (III) in porous media and its transport to groundwater in the percolating soil solution. Binding mechanism is proposed to account for this preferential binding behavior.

关键词： lanthanum adsorption sulfide mineral surface.

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Combining computer vision and deep learning to enable ultra-scale aerial phenotyping and precision agriculture:A case study of lettuce production

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Horticulture Research 2019年第1期6卷 906-917页

作者： alan Bauer Aaron george Bostrom Joshua Ball Christopher Applegate Tao Cheng Stephen Laycock Sergio Moreno Rojas Jacob Kirwan Ji Zhou Earlham Institute Norwich Research ParkNorwich NR47UZUK Plant Phenomics Research Center China-UK Plant Phenomics Research CentreNanjing Agricultural UniversityNanjing 210095 JiangsuChina School of Computing Sciences University of East AngliaNorwich Research ParkNorwich NR47TJUK National Engineering and Technology Center for Information Agriculture MARA Key Laboratory for Crop System Analysis and Decision MakingJiangsu Key Laboratory for Information AgricultureNanjing Agricultural UniversityNanjing 210095 JiangsuChina G’s Growers Limited ElyCambridgeshire CB75TZUK

Aerial imagery is regularly used by crop researchers,growers and farmers to monitor crops during the growing *** extract meaningful information from large-scale aerial images collected from the field,high-throughput phenotypic analysis solutions are required,which not only produce high-quality measures of key crop traits,but also support professionals to make prompt and reliable crop management ***,we report AirSurf,an automated and open-source analytic platform that combines modern computer vision,up-to-date machine learning,and modular software engineering in order to measure yield-related phenotypes from ultra-large aerial *** quantify millions of in-field lettuces acquired by fixed-wing light aircrafts equipped with normalised difference vegetation index(NDVI)sensors,we customised AirSurf by combining computer vision algorithms and a deep-learning classifier trained with over 100,000 labelled lettuce *** tailored platform,AirSurf-Lettuce,is capable of scoring and categorising iceberg lettuces with high accuracy(>98%).Furthermore,novel analysis functions have been developed to map lettuce size distribution across the field,based on which associated global positioning system(GPS)tagged harvest regions have been identified to enable growers and farmers to conduct precision agricultural practises in order to improve the actual yield as well as crop marketability before the harvest.

关键词： computer analysis equipped

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Habitat Suitability Modeling of Endangered Primates in Nigeria: Integrating Satellite Remote Sensing and Spatial Modeling Techniques

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Journal of Geoscience and Environment Protection 2015年第8期3卷 23-38页

作者： Alex O. Onojeghuo alan G. blackburn Francis Okeke Ajoke R. Onojeghuo Lancaster Environment Centre Lancaster University Lancaster UK Department of Surveying and Geoinformatics Nnamdi Azikiwe University Awka Nigeria Wildlife Conservation Society Calabar Nigeria Centre for Landscape and Climate Research University of Leicester Leicester UK

This paper investigates the impacts of forest cover and spatial structure changes on the forest landscape across Afi-Mbe-Okwangwo protected area of Cross River State, Nigeria and its corresponding implication on two endangered primates (Cross River Gorilla and Nigeria-Cameroon Chimpanzee) habitat using satellite remote sensing and modeling techniques. Using remote sensing change detection analysis, the spatial extent and annual rate of deforestation for the study area was determined as 34,620 hectares and 1.5% respectively (from 2000 to 2014). The protected areas with highest annual deforestation rates were Afi Mountain Wildlife Sanctuary (2.6%) and Mbe Mountains (2.2%), both prominent for gorilla and chimpanzee sightings and nests. Further investigations on changes to the forest landscape structure revealed high levels of forest fragmentation across the study area for the 14-year period investigated. As a means of further understanding effects of forest landscapes changes across the study area, a 14-year forward simulation was performed using the Markov model as to determine the spatial extent of futuristic forest cover changes. The results showed that if this current trend of forest cover change continued, 28,121 hectares of forests would be lost to deforestation in 2028 (approximately 16% of the total landmass of the entire study area). Using Maxent modeling, suitable primate habitats were predicted and the total coverage determined as 30,940 hectares (54.4% situated in CRNP—Okwangwo division, 29.4% in AMWS, 14.3% in Mbe Mountains and 1.9% in ARFR). Further analysis revealed 6468 hectares of predicted primate habitat were affected by deforestation in 2014 (21% of the predicted primate habitats). These results indicate that suitable primate habitats (particularly for gorillas and chimpanzees) are under immense pressure from deforestation and forest fragmentation. This paper presents a cost effective and time saving approach for determining suitable primate habitat

关键词： Maxent Remote Sensing Primates GIS Deforestation Markov FRAGSTATS

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鸭茅状摩擦禾种子的物理力学特性

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浙江大学学报（农业与生命科学版） 2018年第4期44卷 507-514页

作者：黄文城张林叶大鹏 TAYLOR alan george 福建农林大学机电工程学院福州350002 康奈尔大学植物科学研究所/纽约州农业试验站美国杰尼瓦14456-0462 现代农业装备福建省高校工程研究中心福州350002

为解决鸭茅状摩擦禾种子因形态结构复杂、种壳坚硬厚实而导致的脱壳困难问题,本研究通过测定和分析完整种子、种壳和颖果的物理力学特性,探讨可行的机械化脱壳方法。结果表明:四倍体品种Meadowcrest种子尺寸和质量均大于二倍体品种Pete,... 详细信息

为解决鸭茅状摩擦禾种子因形态结构复杂、种壳坚硬厚实而导致的脱壳困难问题,本研究通过测定和分析完整种子、种壳和颖果的物理力学特性,探讨可行的机械化脱壳方法。结果表明:四倍体品种Meadowcrest种子尺寸和质量均大于二倍体品种Pete,Meadowcrest和Pete这2个品种的颖果质量各占完整种子质量的1/4和1/3,其完整种子长度均约为颖果长度的2倍;种壳含水率显著低于颖果含水率;种子破裂力大小与压缩方向有关,轴向压缩时完整种子的破裂力为颖果破裂力的1/2～2/3。种子尺寸、水分和破裂力特性共同决定了轴向压缩可能是一种有效分离鸭茅状摩擦禾种子的种壳并获得无损伤颖果的方法。

关键词：鸭茅状摩擦禾种子种壳颖果物理力学特性破裂力

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烧结-硬化时冷却速率的影响

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粉末冶金技术 2014年第2期32卷 144-152页

作者： george Fillari Robert Causton alan Lawley 韩凤麟 Hoeganaes Corporation

烧结-硬化正在成为应用范围较广的生产高强度粉末冶金零件的生产工艺。这种工艺能够使钢件在烧结炉中直接形成马氏体,使得用这种工艺生产的零件性能接近于淬火-回火钢件的性能。也省掉了单独的热处理作业,经济效益也很高。因为烧结-硬... 详细信息

烧结-硬化正在成为应用范围较广的生产高强度粉末冶金零件的生产工艺。这种工艺能够使钢件在烧结炉中直接形成马氏体,使得用这种工艺生产的零件性能接近于淬火-回火钢件的性能。也省掉了单独的热处理作业,经济效益也很高。因为烧结-硬化的成功取决于烧结后加速冷却时,钢件稳定地形成高含量马氏体显微组织的能力。所以本文将研究从烧结温度开始冷却速率的变化对粉末冶金钢的显微组织、硬度及性能的影响。也将进一步说明如何利用比较设备末端淬火与烧结炉的冷却曲线来改进烧结-硬化工艺。

关键词：烧结-硬化冷却速率粉末冶金零件

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DIETARY INTERVENTION TO REDUCE BODY WEIGHT IN OBESE INDIVIDUALS:THE USEFULNESS OF ASPARTAME

DIETARY INTERVENTION TO REDUCE BODY WEIGHT IN OBESE INDIVIDU...

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纽特健康糖（阿斯巴甜）在健康饮食中的应用专题研讨会

作者： george L.blackburn Beatrice S.Kanders Philip T.Lavin Department of Surgery New England Deaconess Hospital Harvard Medical School Boston Massachusetts USA

As China becomes more westernized, the incidence of obesity and diet-related disease will increase. One strategy frequently used in treating obesity is to consume nutrient-modified foods. This study investigated the effect of using nutrient-modified foods containing the high-intensity sweetener aspartame on long-term control of body weight. Specifically, we evaluated whether the addition of foods and beverages containing aspartame to a multidisciplinary weight control program would improve weight loss and long-term control of body weight. One hundred sixty three obese women aged 20 to 60 years were placed on a 19-week balanced deficit diet (1000±200 kcal/d) and randomly assigned to either consume or abstain from aspartame-sweetened foods and beverages during the active weight loss (AWL) phase. Participants were encouraged to continue to consume or abstain from aspartame during the 2.6-year maintenance phase. Data were collected at 19, 71, and 156 weeks from *** in both treatment groups lost a mean of 10% of body weight (10 kg) during the 19 weeks of AWL. Among participants in the aspartame group, aspartame consumption was positively associated with weight loss (p=0.05). During maintenance (week 71), participants in the aspartame group had a 3.1% weight regain, while those in the no-aspartame group regained an average of 4.9%. By week 156, participants in the aspartame group had regained an additional 2.4% (net weight loss from baseline of 5.1%) compared with a gain of 5.4% (net weight loss from baseline of 0.3%) in the no-aspartame group. Using multivariate analysis, the aspartame group retained significantly less weight during maintenance week 71 (p=0.05) and week 156 (p=0.01) than the no-aspartame *** individuals consuming aspartame during a 19-week weight loss program, consuming more aspartame was associated with a greater weight loss. At weeks 71 and 156 of maintenance, participation in a multidisciplinary maintenance program that incorporated

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