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Ocean Data Assimilation Using Intermittent Analyses and Continuous Model Error Correction

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Advances in Atmospheric Sciences 2002年第6期19卷 965-992页

作者： BohuaHuang jamesl.KinterIII PaulS.Schopf Center for Ocean-Land-Atmosphere Studies Institute of Global Environment and Society

A new data insertion approach is applied to the Derber and Rosati ocean data assimilation (ODA) system, a system that uses a variational scheme to analyze ocean temperature and provide ocean model corrections continuously. Utilizing the same analysis component as the original system, the new approach conducts analyses to derive model corrections intermittently at once-daily intervals. A technique similar to the Incremental Analysis Update (IAU) method of Bloom et al. is applied to incorporate the corrections into the model gradually and continuously. This approach is computationally more economical than the original.A 13-year global ocean analysis from 1986 to 1998 is produced using this new approach and compared with an analysis based on the original one. An examination of both analyses in the tropical Pacific Ocean shows that they have qualitatively similar annual and interannual temperature variability. However, the new approach produces smoother monthly analyses. Moreover, compared to the independent

关键词： data assimilation ocean general circulation model ocean current temperature profiles sea surface temperature

The Thermal Behavior of Coal-Ash Deposits on Heat Exchangers

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Journal of Thermal Science 1994年第1期3卷 28-33页

作者： jamesl.S.Chen EverettR.Ramer DepartmentofMechanicalEngineering UniversityofPittsburghPittsburghPA15261USA UnitedStatesDepartme

A theoretical model for predicting the thermal behavior of coal-ash deposits on heat exchangers is desveloped. The heat transfer modes of heat conduction, convection, and thermal radiation are consideredfor the system. The effective thermal conductivities and emissivities of the ash deposits are temperaturedependent. Heat fluxes and dimensionless temperatures in the three layers (loose, sintered, and fused)of the ash deposit are determined. Results are presented for the first two rows of tubes in aligned andstaggered tube banks.

关键词： coal-ash deposits heat exchangers

Structure and activity of thermophilic methanogenic microbial communities exposed to quaternary ammonium sanitizer

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Journal of Environmental Sciences 2017年第6期29卷 164-168页

作者： Jesus D.Fernandez-Bayo Juliano Toniato Blake A.simmons Christopher W.simmons Department of Food Science and Technology University of CaliforniaDauisCA 95616USA Department of Biological and Agricultural Engineering Uniuersity of CaliforniaDauisCA 95616USA Joint BioEnergy Institute EmeryvilleCA 94608USA Biological and Engineering Sciences Center Sandia National LaboratoriesLiuermoreCA 94551USA Energy Efficiency Center University of CaliforniaDauisCA 95616USA

Food processing facilities often use antimicrobial quaternary ammonium compound （QAC） sanitizers to maintain cleanliness. These QACs can end up in wastewaters used as feedstock for anaerobic digestion. The aim of this study was to measure the effect of QAC contamination on biogas production and structure of microbial communities in thermo- philic digester sludge. Methane production and biogas quality data were analyzed in batch anaerobic digesters containing QAC at 0, 15, 50, 100 and 150 mg/L. Increasing sanitizer concentration in the bioreactors negatively impacted methane production rate and biogas quality. Microbial community composition data was obtained through 16S rRNA gene sequencing from the QAG-contaminated sludges. Sequencing data showed no significant restructuring of the bacterial communities. However, significant restructuring was observed within the archaeal communities as QAC concentration increased. Further studies to confirm these effects on a larger scale and with a longer retention time are necessary.

关键词： Anaerobic digestionAntimicrobialsBiofuelsMicrobial ecologyWaste management

Quantifying relationships between subsidence and longwall face advance using DInSAR

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International Journal of Mining Science and Technology 2021年第1期31卷 91-94页

作者： Bailey S.simmons Jessica M.Wempen Department of Mining Engineering University of UtahUT 84112United States

Surface subsidence that results from longwall mining can be large magnitude and can affect significant *** methods for subsidence monitoring include leveling,global positioning system(GPS),and photogrammetric *** sensing techniques including,aerial LiDAR,terrestrial laser scanning,and satellite-based Differential Interferometric Synthetic Aperture Radar(DInSAR),are also used to measure deformation associated with *** data are different than data from conventional subsidence *** capture data over large areas(hundreds of kilometers),and each pixel(data point)in an image quantifies the average displacement over an area of square *** data can have fairly high time resolution;imaging periods typically range from weeks to *** data can be useful to monitor subsidence sequentially over short *** monitoring subsidence may help define if caving is progressing normally and can establish relationships between surface deformation and longwall face advance,which has potential to help quantify possible risks to mine *** this study,subsidence at a longwall trona mine is monitored over short periods,typically 12 days,as the longwall face is advanced through a panel.C-band interferometric wide swath synthetic aperture radar(SAR)images from the sentinel satellites are used to quantify the *** onset of subsidence occurs close in time to the beginning of the longwall face advance,and overall,the development of subsidence closely follows the longwall face advance.

关键词： DInSAR Subsidence Monitoring Longwall Trona

Processing Compressed Expanded Natural Graphite for Phase Change Material Composites

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Journal of Thermal Science 2023年第3期32卷 1213-1226页

作者： Alexander BULK Adewale ODUKOMAIYA Ethan simmons Jason WOODS National Renewable Energy Laboratory 15013 Denver West ParkwayGoldenCO 80401USA

Phase change materials(PCMs)are used in various thermal energy storage applications but are limited by their low thermal *** method to increase conductivity involves impregnating organic PCMs into highly porous conductive matrix *** these materials,compressed expanded natural graphite(CENG)matrices have received the most *** this attention,the effect that CENG processing has on PCM saturation and overall matrix thermal conductivity has not been fully ***,the effect of the heat treatment process used to expand intercalated graphite flakes is evaluated *** heat treatment temperatures yielded higher saturation rates and overall saturation at similar matrix *** example,increasing temperature from 300℃to 700℃resulted in approximately 60%-70%increase in pore saturation after 100 minutes of *** exposure time to heat treatment had less of an effect on PCM *** exposure time had negligible effect above 30 min and above 500℃heating ***,because the expanded graphite was found to oxidize around 700℃,the use of longer exposure time in manufacturing applications can be beneficial if a shortened impregnation time is *** treatment conditions did not impact thermal *** composite latent heat of fusion was also reduced approximately proportionally to the PCM mass fraction.A local maximum in axial thermal conductivity was observed at around 83%porosity,which is similar to previous *** observed conductivity at this maximum was a factor of 81 times greater than the conductivity of the PCM.

关键词： phase change materials thermal energy storage compressed expanded natural graphite thermal conductivity enhancement porous material sorptivity composite matrix

Inundative field releases and evaluation of three predators for Bemisia tabaci （Hemiptera： Aleyrodidae） management in three vegetable crops

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Insect Science 2011年第2期18卷 195-202页

作者： Alvin M. simmons Shaaban Abd-Rabou USDA ARS U.S. Vegetable Laboratory Charleston South Carolina ARC PPRI Dokki Giza Egypt

The sweetpotato whitefly, Bemisia tabaci （Gennadius）（Hemiptera： Aleyrodidae）, is a global pest on numerous crops, including vegetables. Weekly inundative releases of a coccinellid predator （Coccinella undecimpunctata L. [Coleoptera： Coccinellidae]）, a common green lacewing predator （Chrysoperla carnea Stephen [Neuroptera： Chrysopidae]）, and a mirid predator （Macrolophus caliginosus [Wagner] [Hemiptera： Miridae]） were independently made in three vegetable crops （cabbage [Brassica oleracea var. capitata L.], cucumber [Cucumis sativus L.], and squash [Cucurbita pepo L.]） for the management of the sweetpotato whitefly. Approximately 1 million to 2.5 million larvae or nymphs of each predator were released in the vegetable crops during 20 weeks. Whitefly populations were reduced by ≈ 25%-45% during most of the season in each crop where each predator was released. The effect of each predator was similar on whitefly population reduction. Late in the season （October） when whitefly populations were low, generally no benefit was obtained from releasing the predators. Numbers of predators recovered during sampling in all crops were greatest for C. carnea, but this corresponded with the fact that more individuals of this predator were released than any other predator in the experiment. These results help define the utility of these natural enemies for managing B. tabaci in vegetable crops.

关键词： Bemisia tabaci Chrysoperla carnea Coccinella undecimpunctata Macrolophus caliginosus inundative release sweetpotato whitefly

Groundwater Recharge and Mixing in Arid and Semiarid Regions:Heihe River Basin,Northwest China

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Acta Geologica Sinica(English Edition) 2016年第3期90卷 971-987页

作者： CAO Guoliang ZHENG Chunmiao Craig T.simmons Institute of Water Sciences Peking UniversityBeijing 100871China School of the Environment&National Centre for Groundwater Research and Training Adelaide SA 5001Australia School of Environmental Science and Engineering South University of Science and Technology of ChinaShenzhen 518055China Department of Geological Sciences University ofAlabamaTuscaloosaAlabama 35487USA

A sound understanding of groundwater recharged from various sources occurring at different time scales is crucial for water management in arid and semi-arid river basins. Groundwater recharge sources and their geochemical evolution are investigated for the Heihe River Basin （HRB） in northwest China on the basis of a comprehensive compilation of geochemical and isotopic data. Geochemical mass- balance modeling indicates that mountain-block recharge accounts for a small fraction （generally less than 5%） of the shallow and deep groundwater sustaining the oasis, whereas infiltration of rivers and irrigation water contribute most of the groundwater recharge. Dedolomitization is the primary process responsible for the changes in groundwater chemical and carbon isotope compositions from the piedmont to the groundwater discharge zone, where the dedolomitization is very likely enhanced by modern agricultural activities affecting the shallow groundwater quality. Analysis of radioactive isotopes suggests that these primary recharge sources occur at two different time scales. Radiocarbon-derived groundwater age profiles indicate a recharge rate of approximately 12 mm/year, which probably occurred during 2000-7000 years B.P., corresponding to the mid-Holocene humid period. The recharge of young groundwater on the tritium-dated time scale is much higher, about 360 mm/year in the oasis region. Infiltration from irrigation canals and irrigation return flow are the primary contributors to the increased young groundwater recharge. This study suggests that groundwater chemistry in the HRB has been influenced by the complex interaction between natural and human-induced geochemical processes and that anthropogenic effects have played a more significant role in terms of both groundwater quantity and quality.

关键词： Heihe River Basin groundwater recharge groundwater mixing isotope hydrology

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企业如何有效地展示个性

商学院 2024年第6期 15-15页

作者： Lee simmons 斯坦福商学院

在个人生活和职业生涯中,我们常常会面临着一个矛盾:既希望融入社会,受到认可,又渴望展现自身的独特性,脱颖而出。这种挑战不仅存在于个人,也存在于企业。斯坦福商学院组织行为学教授阿米尔·戈德堡指出,企业必须在与众不同和符合潮流... 详细信息

在个人生活和职业生涯中,我们常常会面临着一个矛盾:既希望融入社会,受到认可,又渴望展现自身的独特性,脱颖而出。这种挑战不仅存在于个人,也存在于企业。斯坦福商学院组织行为学教授阿米尔·戈德堡指出,企业必须在与众不同和符合潮流之间找到平衡点。他认为,存在一个最佳的差异化水平,可以在满足行业规范的同时展现独特性。

关键词：组织行为学差异化阿米尔平衡点行业规范融入社会职业生涯斯坦福商学院

Screening large numbers of recombinant plasmids:modifications and additions to alkaline lysis for greater efficiency

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Progress in Natural Science:Materials International 2006年第11期16卷 1231-1232页

作者： N.V.CHANDRASEKHARAN Daniel L.simmons Department of Chemistry and Biochemistry Brigham Young UniversityProvoUtah 84602USA

Selecting bacteria transformed with recombinant plasmid is a laborious step in gene cloning experiments. This selection process is even more tedious when large numbers of clones need to be screened. We describe here modifications to the ultra fast plasmid preparation method described previously by Law and Crickmore. The modified method is coupled to an efficient PCR step to rapidly determine orientation of the inserts. Compared to traditional methods of analysis requiring growth of overnight cultures, plasmid isolation and restriction enzyme digestion to determine orientation this procedure allows for the analysis and storage of a large number of recombinants within a few hours.

关键词： plasmid preparation polymerized chain reaction