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

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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

Side-stream smoking reduces intestinal inflammation and increases expression of tight junction proteins

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World Journal of Gastroenterology 2012年第18期18卷 2180-2187页

作者： Hui Wang Jun-Xing Zhao Nan Hu Jun Ren Min Du Mei-Jun Zhu Department of Animal Science University of Wyoming Laramie WY82071 United States School of Pharmacy University of Wyoming Laramie WY 82071 United States

AIM:To investigate the effect of side-stream smoking on gut microflora composition,intestinal inflammation and expression of tight junction ***:C57BL/6 mice were exposed to side-stream cigarette smoking for one hour daily over eight *** contents were collected for microbial composition *** intestine was collected for immunoblotting and quantitative reverse transcriptase polymerase chain reaction analyses of the inflammatory pathway and tight junction ***:Side-stream smoking induced significant changes in the gut microbiota with increased mouse intestinal bacteria,Clostridium but decreased Fermicutes(Lactoccoci and Ruminococcus),Enterobacteriaceae family and Segmented filamentous baceteria compared to the control ***,side-stream smoking inhibited the nuclear factor-κB pathway with reduced phosphorylation of p65 and IκBα,accompanied with unchanged mRNA expression of tumor necrosis factor-α or *** contents of tight junction proteins,claudin3 and ZO2 were up-regulated in the large intestine of mice exposed side-stream *** addition,side-stream smoking increased c-Jun N-terminal kinase and p38 MAPK kinase signaling,while inhibiting AMPactivated protein kinase in the large ***:Side-stream smoking altered gut microflora composition and reduced the inflammatory response,which was associated with increased expression of tight junction proteins.

关键词： Inflammation Microbiota Tight junction protein Side-stream smoking Intestine

Predicting injury severity and crash frequency:Insights into the impacts of geometric variables on downgrade crashes in wyoming

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第3期7卷 375-383页

作者： Milhan Moomen Mahdi Rez apour Mustaffa NRaja Khaled Ksaibati Department of Civil&Architectural Engineering University of WyomingLaramieWY 82071USA wyoming Technology Transfer Center University of WyomingLaramieWY 82071USA

Road deaths,injuries and property damage places a huge burden on the economy of most *** has one of the highest truck-related fatality rates among the states in the *** high crash rates observed in the state is as a result of many factors mainly related to the challenging mountainous terrain in the state,which places extra burden on truck drivers in terms of requiring higher levels of alertness and driving *** difficult geometry of roads characteristic of mountainous terrain in terms of steep grade lengths adds extra risks of fatalities or injuries occurring as a result of a *** risks are more pronounced for truck-related crashes due to their weight and *** part of the measures to reduce the incidence of truck-related crashes on mountainous areas,the wyoming Department of Transportation(wyDOT)initiated a study to investigate causes of truck crashes on downgrade areas of *** studies have investigated the contributory factors to severe injury crashes but the focus has mostly been on level *** study analyzed the contributory geometric factors of truck crashes on downgrades by estimating three crash prediction negative binomial *** models took into account the injury severity of the *** results indicate that downgrade length,shoulder width,horizontal curve length,number of lanes,number of access points and truck traffic on the highway all impact truck-related crashes and injury frequencies ondowngrades in *** results of this study will be helpful to future downgrade road design policy aimed at reducing downgrade truck related crashes.

关键词： Traffic safety Downgrade Crash frequency Truck safety Geometric factor

Probing Electrocatalytic CO_(2) Reduction at Individual Cu Nanostructures via Optically Targeted Electrochemical Cell Microscopy

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Journal of Analysis and Testing 2019年第2期3卷 140-149页

作者： Joshua D.Walmsley Joshua W.Hill Partha Saha Caleb M.Hill Department of Chemistry University of WyomingLaramieWY 82071USA

Optically targeted electrochemical cell microscopy(OTECCM)was applied to measure electrocatalytic rates at individual Cu nanoparticles(NPs)under electrolyte conditions relevant to CO_(2) *** electrocatalytic responses from individual NPs were found to exhibit a wide variation in behavior,with significant NP-to-NP variations in the magnitude of electrocata-lytic currents and necessary overpotentials being *** of these quantities with metrics of NP size suggest no significant variations in the inherent electrocatalytic activity of the NPs with *** element simulations of diffusion in this system demonstrate the observed diffusion-limited currents are significantly smaller than expected,attributable to the presence of a significant amount of residual ligand on the surface of the Cu NPs,which were prepared via an organic phase *** results presented here further demonstrate the promise of techniques which employ correlated optical and electrochemical measurements,such as OTECCM,for studying electrocatalysis at individual NPs.

关键词： Electrochemistry Electrochemical microscopy Nanoparticles CO_(2)reduction

Partial proportional odds model for analyzing pedestrian crashes,threshold heterogeneity by scale and proportional odds factor

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第6期9卷 969-977页

作者： Mahdi Rezapour Khaled Ksaibati wyoming Technology Transfer Center University of WyomingLaramieWY 82071USA

Despite low traffic in wyoming,pedestrian crash severity accounts for a high number of fatalities in the *** this study was conducted to highlights factors contributing to those *** results highlighted that drivers under influence,type of vehicle,location of crashes,estimated speed of vehicles,driving over the recommended speed are some of factors contributing to the severity of *** this study,we used proportional odds model which assumes that the impact of each attribute is consistent or proportional across various threshold ***,it has been argued that this assumption might be unrealistic,especially at the presence of extreme ***,the assumption was relaxed in this study by shifting the thresholds based on some explanatory attributes,or proportional odds *** addition,we accounted for the spread rate,or scale,of the model’s latent distribution of pedestrian *** results highlighted that the partial proportional odds model through proportional odds factor and scale effects result in a significant improvement in model fit compared with the standard proportional odds *** were also made across standard normal,simple partial ordinal model,and partial ordinal accounting for scale *** addition,various potential threshold structures such as symmetric and flexible were considered,but similar goodness of fits were observed across all those *** discussion has been made regarding the formulation of the implemented methodology,and its implications.

关键词： Partial proportional odds model Pedestrian crashes Scale heterogeneity Proportional odds factor Vulnerable road users Drivers’lack of attention

Spatial and Temporal Variability of Drought Patterns over the Continental United States from Observations and Regional Climate Models

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Journal of Meteorological Research 2021年第2期35卷 295-312页

作者： Yog ARYAL Jianting ZHU Department of Civil and Architectural Engineering University of WyomingLaramieWY 82071USA

The aim of this study is to analyze the spatial and temporal structure of drought over the continental United States(CONUS) and their teleconnection at different timescales from observations and climate models. We use the standardized precipitation evapotranspiration index(SPEI) at 12-and 24-month timescales as the drought index. Spatial patterns of drought regimes are delineated by using the principal component analysis(PCA) while the temporal characteristics of the variability of each drought pattern and teleconnection with climate indices are analyzed by using the wavelet analysis. Wavelet coherence of the drought pattern and four climate indices: El Ni?o–Southern Oscillation(ENSO), Pacific decadal oscillation(PDO), Atlantic multidecadal oscillation(AMO), and North Atlantic Oscillation(NAO) are analyzed. The results show that major drought patterns are located over the Northwest, South, Upper Midwest, and East regions. The spatial pattern of the drought regimes is similar for the 12-and 24-month timescale drought. ENSO influences the drought over West and South at decadal timescales throughout the study period(1950–2015) while intermittent significant coherence is observed at interannual timescale. The coherence of NAO and PDO with SPEI-12 is decreased during recent decades. Generally, regional climate model(RCM)-simulated drought patterns are more localized in a smaller area over the region compared to the spatial extent of observed drought patterns. Power spectra of seasonal to interannual variability(2–5-yr period) of all four drought patterns from RCM simulations are similar to those from the observations. However, at larger periodicities(decadal variations)among-RCM spread increases with increasing periods.

关键词： drought pattern principal component analysis(PCA) climate teleconnection wavelet analysis

ML(n)BiCGStab: Reformulation, Analysis and Implementation

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Numerical Mathematics(Theory,Methods and Applications) 2012年第3期5卷 447-492页

作者： Man-Chung Yeung Department of Mathematics University of WyomingLaramieWY 82071USA

With the aid of index functions,we re-derive the ML(n)BiCGStab algorithm in[Yeung and Chan,SIAM ***.,21(1999),pp.1263-1290]*** are n ways to define the ML(n)BiCGStab residual *** definition leads to a different ML(n)BiCGStab *** demonstrate this by presenting a second algorithm which requires less *** theory,this second algorithm serves as a bridge that connects the Lanczos-based BiCGStab and the Arnoldi-based FOM while ML(n)BiCG is a bridge connecting BiCG and *** also analyze the breakdown situation from the probabilistic point of view and summarize some useful properties of ML(n)*** issues are also addressed.

关键词： CGS BiCGStab ML(n)BiCGStab multiple starting Lanczos Krylov subspace iterative methods linear systems

Sequential Gaussian simulation for geosystems modeling:A machine learning approach

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Geoscience Frontiers 2022年第1期13卷 1-14页

作者： Tao Bai Pejman Tahmasebi College of Engineering and Applied Science University of WyomingLaramieWY 82071USA

Sequential Gaussian Simulation(SGSIM)as a stochastic method has been developed to avoid the smoothing effect produced in deterministic methods by generating various stochastic *** of the main issues of this technique is,however,an intensive computation related to the inverse operation in solving the Kriging system,which significantly limits its application when several realizations need to be produced for uncertainty *** this paper,a physics-informed machine learning(PIML)model is proposed to improve the computational efficiency of the *** this end,only a small amount of data produced by SGSIM are used as the training dataset based on which the model can discover the spatial correlations between available data and unsampled *** achieve this,the governing equations of the SGSIM algorithm are incorporated into our proposed *** quality of realizations produced by the PIML model is compared for both 2D and 3D cases,visually and ***,computational performance is evaluated on different grid *** results demonstrate that the proposed PIML model can reduce the computational time of SGSIM by several orders of magnitude while similar results can be produced in a matter of seconds.

关键词： Artificial intelligence Uncertainty Geosystems Statistical modeling

Incorporating truncated fractal distribution into Maxwell model to quantify thermal conductivity and its uncertainty in heterogeneous multiparticle systems

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Particuology 2023年第9期80卷 81-89页

作者： Jianting Zhu Department of Civil and Architectural Engineering and Construction Management University of WyomingLaramieWY82071USA

An approach is developed to examine the mean and uncertainty of thermal conductivity of a heterogeneous multiparticle system,where the particle concentration or void fraction is treated as a truncated fractal *** truncated fractal distribution is then integrated into the Maxwell model,which is equivalent to a cell model in which the multiparticle system is conceptualized as a spherical fluid cell that envelopes a solid *** developed mean thermal conductivity is compared with four experimental data sets of liquid-saturated media from the *** effect of fractal characteristics is quantified and *** particle concentration or void fraction truncated fractal distribution can better capture scatters in the experimental *** thermal conductivity and its standard deviation decrease with increasing fractal *** the void fraction is truncated fractal,the uncertainty increases mostly in the low mean void fraction range and drops more quickly with the increasing mean void fraction compared to the case where the particle concentration is truncated *** a typical case of multiparticle system when the solid particles are more conductive than the fluid,the faster increase rate of standard deviation with the ratio of solid over fluid conductivities occurs when the mean void fraction is smaller.

关键词： Thermal conductivity Heterogeneous multiparticle system Truncated fractal distribution Particle concentration Void fraction